Sample records for led traffic signal

  1. Vehicle Traffic Control Signal Heads— Light Emitting Diode Circular Signal Supplement (VTCSH-LED). This replaced the so-called Interim LED Purchase Specifications,

    E-Print Network [OSTI]

    S. Behura

    Engineers ’ (ITE) specification for light-emitting diode (LED) circular traffic signals recently was updated (June 27, 2005) and published under the name

  2. LED Traffic Light as a Communications Device Grantham Pang, Thomas Kwan, Chi-Ho Chan, Hugh Liu.

    E-Print Network [OSTI]

    Pang, Grantham

    :http://www.eee.hku.hk/~gpang Abstract The visible light from an LED (light emitting diode) traffic light can be modulated and encoded on the description of an audio information system made up of high brightness, visible light emitting diodes (LEDs messages 1. Introduction Recently, high intensity light emitting diodes for traffic signals are available

  3. DUAL USE OF LEDS: SIGNALING AND COMMUNICATIONS IN ITS Grantham Pang, Chi-ho Chan, Hugh Liu, Thomas Kwan

    E-Print Network [OSTI]

    Pang, Grantham

    of an incandescent lamp is 800 hours while the life expectancy of LED is 10-23 years. This result shows that LED has : · LED indicator lamps (as in some dashboard, traffic signals, card readers). · LED displays (1 DUAL USE OF LEDS: SIGNALING AND COMMUNICATIONS IN ITS Grantham Pang, Chi-ho Chan, Hugh Liu

  4. Seven Traffic Signals in Two Minutes

    Broader source: Energy.gov [DOE]

    Topeka, Kansas has activated the first of three key traffic corridors to receive a "green light tunnel," a real-time adaptive traffic signal system that synchronizes signals to create a series of...

  5. LED Traffic Lights Get Buy American Stamp | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742Energy ChinaofSchaeferApril 1, 1999 InspectionVolunteersKarenThisDepartment ofLED traffic lights

  6. Seven Traffic Signals in Two Minutes

    SciTech Connect (OSTI)

    None

    2011-01-01T23:59:59.000Z

    Topeka, KS has activated the first of three key traffic corridors to receive a "green light tunnel," a real-time adaptive traffic signal system that synchronizes signals to create a series of green lights for motorists. The result is fewer stops, less travel time and -- most importantly -- a lot of saved gasoline.

  7. Performance Analysis of Isolated Intersection Traffic Signals 

    E-Print Network [OSTI]

    Yin, Kai

    2013-08-01T23:59:59.000Z

    This dissertation analyzes two unsolved problems to fulfill the gap in the literature: (1). What is the vehicle delay and intersection capacity considering left-turn traffic at a pre-timed signal? (2). What are the mean and variance of delay...

  8. Performance Analysis of Isolated Intersection Traffic Signals

    E-Print Network [OSTI]

    Yin, Kai

    2013-08-01T23:59:59.000Z

    This dissertation analyzes two unsolved problems to fulfill the gap in the literature: (1). What is the vehicle delay and intersection capacity considering left-turn traffic at a pre-timed signal? (2). What are the mean and variance of delay...

  9. Gresham/Multnomah County Phase 3 Traffic Signal System Optimization September 2008 Adaptive Traffic Signal Control System Benefits Report

    E-Print Network [OSTI]

    Bertini, Robert L.

    Gresham/Multnomah County Phase 3 Traffic Signal System Optimization September 2008 Adaptive Traffic Signal Control System Benefits Report Page i TTAABBLLEE OOFF CCOONNTTEENNTTSS 1 Executive Summary......................................................................................................................15 2.3.1 System Evaluation

  10. actuated traffic signal controllers: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ramanan Venkat 2012-01-01 8 UNCORRECTED 2 Stochastic adaptive control model for traffic signal systems Environmental Sciences and Ecology Websites Summary: process. The model...

  11. LIGHT EMITTING DIODE (LED) TRAFFIC SIGNAL SURVEY RESULTS

    E-Print Network [OSTI]

    Joaquin County Salinas Simi Valley West Sacramento San Luis Obispo County San Anselmo Solvang Westlake

  12. Transforming Traffic Signals to Support Sustainability

    E-Print Network [OSTI]

    Bertini, Robert L.

    transportation modes · Go beyond minimum design standards · Improve nonmotorized facilities during maintenance trafficed locations #12;· Intersection treatment #12;Graphic by Bill Kloos, City of Port · Traditional

  13. Evaluation of detector placement strategies for first generation traffic responsive signal control

    E-Print Network [OSTI]

    Brehmer, Christopher Lynn

    1996-01-01T23:59:59.000Z

    Traffic responsive signal systems rely on system detector data to evaluate current traffic conditions and select a corresponding timing plan from a library of plans. One of the major decisions surrounding the use of traffic responsive signal systems...

  14. UNCORRECTED 2 Stochastic adaptive control model for traffic signal systems

    E-Print Network [OSTI]

    Detwiler, Russell

    UNCORRECTED PROOF 1 2 Stochastic adaptive control model for traffic signal systems 3 X.-H. Yu a,1 , W.W. Recker b,* 4 a Department of Electrical Engineering, California Polytechnic State University

  15. An operational analysis of flashing traffic signal operation

    E-Print Network [OSTI]

    Benz, Robert Joseph

    1993-01-01T23:59:59.000Z

    AN OPERATIONAL ANALYSIS OF FLASHING TRAFFIC SIGNAL OPERATION A Thesis by ROBERT JOSEPH BENZ Submitted to the Office of Graduate Studies of Texas AEcM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE... street volumes are below 250 vph per approach and for main street volume of 500 vph per approach when the main/minor street volume ratio is above two. The volume range exceeds the Warrant 1 the minimum volume warrant for traffic signal installation...

  16. Evaluation of traffic signal controller transition methods

    E-Print Network [OSTI]

    Hamilton, Curtis Lloyd

    2000-01-01T23:59:59.000Z

    % capacity at the coordinated phase for the 30 minutes and at no volume for the remaining 5 minutes. The signal timing plans were fixed at a 120-second cycle length. The transition methods for each of the offset changes were tested to find the method...

  17. Preemption strategy for traffic signals at intersections near highway-railroad grade crossings

    E-Print Network [OSTI]

    Cho, Hanseon

    2004-09-30T23:59:59.000Z

    Because the operational characteristics of signalized intersections near highway-railroad grade crossings (IHRGCs) are different from those of signalized intersections located elsewhere in the traffic system, standard operational strategies do...

  18. area traffic signal control: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    technology, are to increase the safety and through-put of the existing highway by traffic automation. Advanced Vehicle Control... Huandra, Rusli 1998-01-01 102 Evaluation of...

  19. Strategies for improving traffic operations at oversaturated signalized diamond interchanges

    E-Print Network [OSTI]

    Herrick, George Curtis

    1992-01-01T23:59:59.000Z

    to reduce both recurring and nonrecurring congestion. Incident detection and management systems can be implemented on freeways to decrease incident durations and reduce the resulting traffic congestion. Surveillance and control systems can be integrated... urban diamond interchanges, the traffic engineer needs to better understand these control strategies and seek new and innovative control strategies to more effectively address them. This research addressed two major objectives. The first objective...

  20. An analysis of peak traffic demand at signalized urban intersections

    E-Print Network [OSTI]

    Drew, Donald R

    1961-01-01T23:59:59.000Z

    (3 LANES) 350 705 7:15 725 7:35 7:45 7:55 805 TIME INTERVAL TYPICAL PEAK HOUR 5 MIN. TRAFFIC FLOWS 3 ? LANE FREEWAY 100 90 80 UI Z 3 70 0 PEAK RATES OF FLOW FORT WORTH UNIFORM ARRIVALS 0 ~ o170 EQUIVALENT RATE OF FLOW 60 50 O... {Figure 3), it is seen thai from 7:10 A. M. to 7:45 A. Lvf . the average hourly rate of flow is exceeded. If the mid-points of the five-minute ordinates are connected, a polygon is formed which:ntersects the PHV at the extremities of the peak period...

  1. Arterial-street signal timing strategies to provide additional through-traffic capacity during freeway incident conditions

    E-Print Network [OSTI]

    Dale, James Joseph

    1992-01-01T23:59:59.000Z

    relationships identified are likely to be common to other arterial-street sections with similar configurations and traffic patterns. ACKNOWLEDGMENTS This research was funded by Project No. 30, "Fuel Savings from Surveillance, Signing, and Signal Control... timing plan to accommodate diverted traffic from a freeway plays a significant role in the development of integrated freeway and arterial street control systems like the Automated Traffic Surveillance gnd control (ATSAC) system in Los Angeles (Rowe...

  2. Optical Wireless based on High Brightness Visible LEDs Grantham Pang, Thomas Kwan, Hugh Liu, Chi-Ho Chan

    E-Print Network [OSTI]

    Pang, Grantham

    and encoded with audio or data signal. Hence, an LED indicator lamp or traffic light can become an information for incandescent lamps [3,4]. This advancement has led to the production of large- area full-color LED displaysOptical Wireless based on High Brightness Visible LEDs Grantham Pang, Thomas Kwan, Hugh Liu, Chi

  3. An investigation into the use of highway traffic signals at highway-railroad grade crossings

    E-Print Network [OSTI]

    Frieslaar, Andre Henry

    1997-01-01T23:59:59.000Z

    2 Highway Speed Limit Classification 3 Light Condition Classification 4 Presence of Drunk Driver Classification 5 Driver Age Group Classification . . 43 50 52 57 LIST OF TABLES TABLE Page 1 Fatal Accidents Based on FARS Traffic Control... Device 2 Traffic Control Comparison between FARS and DOT/AAR Databases. . . 3 Fatal Accident Rates Based on DOT/AAR Traffic Control Device . 4 Driver Related Factor Results 5 FARS Variables Used in Analysis . 6 Driver Related Factor Classification...

  4. Development of a Web-based Emissions Reduction Calculator for Street Light and Traffic Light Retrofits

    E-Print Network [OSTI]

    Liu, Z.; Gilman, D.; Haberl, J. S.; Culp, C.

    2005-01-01T23:59:59.000Z

    , street lights and traffic lights represent one of the largest categories of electricity used by a city. By retrofitting the street lights with energy efficient lamps such as high pressure sodium and metal halide and traffic lights with light-emitting... diode (LED) traffic signals, a city 1 In the 2003 and 2005 Texas State legislative sessions, the emissions reductions legislation in Senate Bill 5 was modified by House bill 3235, and House bill 1365...

  5. Correlation of Beam Electron and LED Signal Losses under Irradiation and Long-term Recovery of Lead Tungstate Crystals

    E-Print Network [OSTI]

    V. A. Batarin; J. Butler; A. M. Davidenko; A. A. Derevschikov; Y. M. Goncharenko; V. N. Grishin; V. A. Kachanov; A. S. Konstantinov; V. I. Kravtsov; Y. Kubota; V. S. Lukanin; Y. A. Matulenko; Y. M. Melnick; A. P. Meschanin; N. E. Mikhalin; N. G. Minaev; V. V. Mochalov; D. A. Morozov; L. V. Nogach; A. V. Ryazantsev; P. A. Semenov; V. K. Semenov; K. E. Shestermanov; L. F. Soloviev; S. Stone; A. V. Uzunian; A. N. Vasiliev; A. E. Yakutin; J. Yarba

    2005-04-13T23:59:59.000Z

    Radiation damage in lead tungstate crystals reduces their transparency. The calibration that relates the amount of light detected in such crystals to incident energy of photons or electrons is of paramount importance to maintaining the energy resolution the detection system. We report on tests of lead tungstate crystals, read out by photomultiplier tubes, exposed to irradiation by monoenergetic electron or pion beams. The beam electrons themselves were used to measure the scintillation light output, and a blue light emitting diode (LED) was used to track variations of crystals transparency. We report on the correlation of the LED measurement with radiation damage by the beams and also show that it can accurately monitor the crystals recovery from such damage.

  6. Traffic-Aware Data and Signaling Resource Management for Green Cellular Networks

    E-Print Network [OSTI]

    of Signaling to Data (RSD). It is defined as the ratio f of the number of physical resource blocks (PRB) for signaling over the number of physical resource blocks for data, that is, RSD : f = Number of PRB for signaling Number of PRB for data . (1) This metric is evaluated for the background, IM, and web browsing

  7. LED Update

    SciTech Connect (OSTI)

    Johnson, Mark L.; Gordon, Kelly L.

    2006-09-01T23:59:59.000Z

    This article, which will appear in RESIDENTIAL LIGHTING MAGAZINE, interviews PNNL's Kelly Gordon and presents the interview in question and answer format. The topic is a light emitting diode (LED) lighting also known as solid state lighting. Solid state lighting will be a new category in an energy efficient lighting fixture design competition called Lighting for Tomorrow sponsored by the US Department of Energy Emerging Technologies Office, the American Institute for Lighting, and the Consortium for Energy Efficiency. LED technology has been around since the ’60s, but it has been used mostly for indicator lights on electronics equipment. The big breakthrough was the development in the 1990s of blue LEDs which can be combined with the red and green LEDs that already existed to make white light. LEDs produce 25 to 40 lumens of light per watt of energy used, almost as much as a CFL (50 lumens per watt) and much more efficient than incandescent sources, which are around 15 lumens per watt. They are much longer lived and practical in harsh environments unsuitable for incandescent lighting. They are ready for niche applications now, like under-counter lighting and may be practical for additional applications as technological challenges are worked out and the technology is advancing in leaps and bounds.

  8. LED lamp

    DOE Patents [OSTI]

    Galvez, Miguel; Grossman, Kenneth; Betts, David

    2013-11-12T23:59:59.000Z

    There is herein described a lamp for providing white light comprising a plurality of light sources positioned on a substrate. Each of said light sources comprises a blue light emitting diode (LED) and a dome that substantially covers said LED. A first portion of said blue light from said LEDs is transmitted through said domes and a second portion of said blue light is converted into a red light by a first phosphor contained in said domes. A cover is disposed over all of said light sources that transmits at least a portion of said red and blue light emitted by said light sources. The cover contains a second phosphor that emits a yellow light in response to said blue light. The red, blue and yellow light combining to form the white light and the white light having a color rendering index (CRI) of at least about 80.

  9. LED lamp power management system and method

    DOE Patents [OSTI]

    Gaines, James; Clauberg, Bernd; Van Erp, Josephus A. M.

    2013-03-19T23:59:59.000Z

    An LED lamp power management system and method including an LED lamp having an LED controller 58; a plurality of LED channels 60 operably connected to the LED controller 58, each of the plurality of LED channels 60 having a channel switch 62 in series with at least one shunted LED circuit 83, the shunted LED circuit 83 having a shunt switch 68 in parallel with an LED source 80. The LED controller 58 reduces power loss in one of the channel switch 62 and the shunt switch 68 when LED lamp electronics power loss (P.sub.loss) exceeds an LED lamp electronics power loss limit (P.sub.lim); and each of the channel switches 62 receives a channel switch control signal 63 from the LED controller 58 and each of the shunt switches 68 receives a shunt switch control signal 69 from the LED controller 58.

  10. Introducing Traffic Analysis Attacks, Defences and Public Policy Issues. . .

    E-Print Network [OSTI]

    Danezis, George

    Roots Traffic analysis is a key part of signal intelligence and electronic warfare. Michael Hermann, who

  11. Introducing Traffic Analysis George Danezis and Richard Clayton

    E-Print Network [OSTI]

    Danezis, George

    . 2 Military Roots Traffic analysis is a key component of signal intelligence and electronic warfare

  12. Vapochromic LED

    DOE Patents [OSTI]

    Kunugi, Yoshihito (Hiroshima, JP); Mann, Kent R. (North Oaks, MN); Miller, Larry L. (Minnetonka, MN); Exstrom, Christopher L. (Kearney, NE)

    2003-06-17T23:59:59.000Z

    A sandwich device was prepared by electrodeposition of an insoluble layer of oligomerized tris(4-(2-thienyl)phenyl)amine onto conducting indium-tin oxide coated glass, spin coating the stacked platinum compound, tetrakis(p-decylphenylisocyano)platinum tetranitroplatinate, from toluene onto the oligomer layer, and then coating the platinum complex with aluminum by vapor deposition. This device showed rectification of current and gave electroluminescence. The electroluminescence spectrum (.lambda..sub.max =545 nm) corresponded to the photoluminescence spectrum of the platinum complex. Exposure of the device to acetone vapor caused the electroemission to shift to 575 nm. Exposure to toluene vapor caused a return to the original spectrum. These results demonstrate a new type of sensor that reports the arrival of organic vapors with an electroluminescent signal. The sensor comprises (a) a first electrode; (b) a hole transport layer formed on the first electrode; (c) a sensing/emitting layer formed on the hole transport layer, the sensing/emitting layer comprising a material that changes color upon exposure to the analyte vapors; (d) an electron conductor layer formed on the sensing layer; and (e) a second electrode formed on the electron conductor layer. The hole transport layer emits light at a shorter wavelength than the sensing/emitting layer and at least the first electrode comprises an optically transparent material.

  13. Vapochromic LED

    DOE Patents [OSTI]

    Kunugi, Yoshihito (Hiroshima, JP); Mann, Kent R. (North Oaks, MN); Miller, Larry L. (Minnetonka, MN); Exstrom, Christopher L. (Kearney, NE)

    2002-01-15T23:59:59.000Z

    A sandwich device was prepared by electrodeposition of an insoluble layer of oligomerized tris(4-(2-thienyl)phenyl)amine onto conducting indium-tin oxide coated glass, spin coating the stacked platinum compound, tetrakis(p-decylphenylisocyano)platinum tetranitroplatinate, from toluene onto the oligomer layer, and then coating the platinum complex with aluminum by vapor deposition. This device showed rectification of current and gave electroluminescence. The electroluminescence spectrum (.mu..sub.max =545 nm) corresponded to the photoluminescence spectrum of the platinum complex. Exposure of the device to acetone vapor caused the electroemission to shift to 575 nm. Exposure to toluene vapor caused a return to the original spectrum. These results demonstrate a new type of sensor that reports the arrival of organic vapors with an electroluminescent signal. The sensor comprises (a) a first electrode; (b) a hole transport layer formed on the first electrode; (c) a sensing/emitting layer formed on the hole transport layer, the sensing/emitting layer comprising a material that changes color upon exposure to the analyte vapors; (d) an electron conductor layer formed on the sensing layer; and (e) a second electrode formed on the electron conductor layer. The hole transport layer emits light at a shorter wavelength than the sensing/emitting layer and at least the first electrode comprises an optically transparent material.

  14. The RTMS (Remote Traffic Microwave Sensor) unit is a traffic sensor which uses microwave signals to detect vehicles. Unlike sensors which use the Doppler effect, this sensor

    E-Print Network [OSTI]

    Prevedouros, Panos D.

    counter unit. Additional items for deployment include solar panel, batteries and modem with cellular dimly. The LED is bright only when data is being downloaded from it. Solar Panel The solar panel batteries are used they must be connected in parallel. The solar panel, batteries, and the load all connect

  15. Determination of traffic responsive plan selection factors and thresholds using artificial neural networks

    E-Print Network [OSTI]

    Sharma, Anuj

    2004-11-15T23:59:59.000Z

    Traffic congestion has become a menace to civilized society. It degrades air quality, jeopardizes safety and causes delay. Traffic congestion can be alleviated by providing an effective traffic control signal system. Closed-loop traffic control...

  16. LED Market Intelligence Report

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    early adopters of LED technologies, particularly around dimming capabilities. 16 LED Market Intelligence Report Home Depot Walmart Cree Philips TCP GE LSG Osram Feit Costco...

  17. 2007 IEEE International Conference on Signal Processing and Communications (ICSPC 2007), 24-27 November 2007, Dubai, United Arab Emirates A MODLE FOR CONTROLLED VBR VIDEO TRAFFIC

    E-Print Network [OSTI]

    Gabbouj, Moncef

    -27 November 2007, Dubai, United Arab Emirates A MODLE FOR CONTROLLED VBR VIDEO TRAFFIC Mehdi Rezaei, 2Imed

  18. LEDs_3LEDs_3 current efficiency

    E-Print Network [OSTI]

    Pulfrey, David L.

    efficiencySec. 8.2 From our toolbox Current efficiency #12;4 Light extraction efficiencyLight extraction extraction efficiencyDesign to improve extraction efficiencySec. 8.4 What are the features of this LED from;6 Various efficienciesVarious efficienciesSecs. 8.4, 8.5 Present record is 56%Wall-plug efficiency Wall

  19. LED Lighting Retrofit

    E-Print Network [OSTI]

    Shaw-Meadow, N.

    2011-01-01T23:59:59.000Z

    ? Municipal Street Lighting Consortium ? American Public Power Association (APPA) ? Demonstration in Energy Efficiency Development (DEED) ? Source of funding and database of completed LED roadway projects 6 Rules of the Road ESL-KT-11-11-57 CATEE 2011..., 2011 ? 9 Solar-Assisted LED Case Study LaQuinta Hotel, Cedar Park, Texas ? Utilizes 18 - ActiveLED Solar-Assisted Parking Lot Lights ? Utilizes ?power management? to extend battery life while handling light output ? Reduces load which reduces PV...

  20. LED Lighting Basics

    Broader source: Energy.gov [DOE]

    Light-Emitting diodes (LEDs) efficiently produce light in a fundamentally different way than any legacy or traditional source of light.

  1. Sandia National Laboratories: LED

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    electroluminescence was first reported by H.J. Round in 1907, and the first light-emitting diode (LED) was reported by O.V. Losev in 1927. Not until the birth of semiconductor...

  2. LED MR16 Lamps

    Broader source: Energy.gov [DOE]

    The following CALiPER report provides detailed analysis of LED MR16 lamp performance, covering basic performance characteristics as well as subjective evaluation of beam, shadow, and color quality. Pending reports will offer analysis on performance attributes that are not captured by LM-79 testing. These reports are intended to educate the industry on market trends, potential issues, and important areas for improvement.

  3. Global LED Manufacturing

    Energy Savers [EERE]

    0.20.5W 5630 PPA 0.51.0W 7030 PCT XVGA HDMI UHD 4K2K UHD 8K4K 0.81.2W 3030 EMC 1.22.0W 3535 EMC w Flip-Chip 0.50.8W 2835 PCT ? 1.01.5 W ???? Revolution of LED...

  4. Development and Evaluation of an Advanced LED Warning System for

    E-Print Network [OSTI]

    Minnesota, University of

    .dot.state.mn.us/stateaid/sa_traffic_safety.html #12;Project Need · ITS Safety Plan: ITS Critical Strategy 5: Use Intersection Collision Warning.g. radar) · Utilize alternative energy source (solar and/or wind) · Utilize LED blinker signs #12;Before;Stop Case 2: #12;Roll-through Case: #12;Acknowledgments and Special Thanks · Local Road Research Board

  5. VEHICLE EMISSIONS AND TRAFFIC MEASURES: EXPLORATORY ANALYSIS OF FIELD

    E-Print Network [OSTI]

    Frey, H. Christopher

    VEHICLE EMISSIONS AND TRAFFIC MEASURES: EXPLORATORY ANALYSIS OF FIELD OBSERVATIONS AT SIGNALIZED between vehicle emissions and traffic control measures is an important step toward reducing the potential roadway design and traffic control, have the ability to reduce vehicle emissions. However, current vehicle

  6. LED Price Tracking Form

    Broader source: Energy.gov [DOE]

    DOE intends to update the SSL Pricing and Efficacy Trend Analysis for Utility Program Planning report on an annual basis, but doing so requires that we have sufficient product and purchase data including acquisition date, purchase price, product category, and rated initial lumens. Those interested in helping collect this data are asked to use the LED Price Tracking FormMicrosoft Excel and follow the instructions for submitting data.

  7. LED PAR38 Lamps

    Broader source: Energy.gov [DOE]

    The following CALiPER reports provide detailed analysis of LED PAR38 lamp performance, covering basic performance characteristics as well as subjective evaluation of beam, shadow, and color quality. Pending reports will offer analysis on flicker, dimming and power quality characteristics; stress testing; and lumen and chromaticity maintenance. These reports are intended to educate the industry on market trends, potential issues, and important areas for improvement.

  8. California Says''Go'' to Energy-Saving Traffic Lights

    SciTech Connect (OSTI)

    Not Available

    2004-05-01T23:59:59.000Z

    DOE's State Energy Program published this case study in conjunction with the California Energy Commission. It describes the growing use of traffic lights employing the technology of light emitting diodes, or LEDs. Such traffic lights use less energy and produce a brighter illumination.

  9. HPSS Yearly Network Traffic

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    growth in network traffic to storage over the years. Network Traffic Growth Network Distribution 2010 Network Distribution 2010 Network Distribution 2009 Network Distribution...

  10. Traffic Synchronization and Management for Energy Savings 5-18...

    Broader source: Energy.gov (indexed) [DOE]

    the corridor, and it's seven or eight traffic signals. You can also see the camera on the signal pole. The next slide is another view of the area, where you can also see the camera...

  11. LED Record Efficacy and Brightness

    Broader source: Energy.gov [DOE]

    Designed for general lighting applications such as street, industrial, and parking garage lighting, the Cree XLamp® power LED sets new records for LED brightness and efficacy, up to 85 lm/W at 350 mA. The XLamp utilizes Cree's performance breakthrough EZBright™ LED chip; both products include technology that was developed in part with R&D funding support from DOE.

  12. Fermilab | Traffic Safety at Fermilab |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Submit a SuggestionQuestion Fermilab traffic rules (FESHM 9010) Fermilab traffic accident statistics Traffic safety awareness training Resources Texting While Driving...

  13. Ongoing LED RD Challenges (LED droop still challenge)

    Energy Savers [EERE]

    and Nonpolar GaN Semi polar GaN SOLUTION New GaN Crystal Planes * Semipolar planes for blue, green and yellow LEDs A. Romanov et al. : J. Appl. Phys. 100 (2006) 023533. (1122)...

  14. Metacapacitors for LED Lighting: Metacapacitors

    SciTech Connect (OSTI)

    None

    2010-09-02T23:59:59.000Z

    ADEPT Project: The CUNY Energy Institute is developing less expensive, more efficient, smaller, and longer-lasting power converters for energy-efficient LED lights. LEDs produce light more efficiently than incandescent lights and last significantly longer than compact fluorescent bulbs, but they require more sophisticated power converter technology, which increases their cost. LEDs need more sophisticated converters because they require a different type of power (low voltage direct current, or DC) than what's generally supplied by power outlets. The CUNY Energy Institute is developing sophisticated power converters for LEDs that contain capacitors made from new, nanoscale materials. Capacitors are electrical components that are used to store energy. CUNY's unique capacitors are configured with advanced power circuits to more efficiently control and convert power to the LED lighting source. They also eliminate the need for large magnetic components, instead relying on networks of capacitors that can be easily printed on plastic substrate. CUNY's prototype LED power converter already meets DOE's 2020 projections for the energy efficiency of LED power converters.

  15. Sandia National Laboratories: white LED

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    electroluminescence was first reported by H.J. Round in 1907, and the first light-emitting diode (LED) was reported by O.V. Losev in 1927. Not until the birth of semiconductor...

  16. Sandia National Laboratories: Red LED

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    electroluminescence was first reported by H.J. Round in 1907, and the first light-emitting diode (LED) was reported by O.V. Losev in 1927. Not until the birth of semiconductor...

  17. Sandia National Laboratories: Blue LED

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    electroluminescence was first reported by H.J. Round in 1907, and the first light-emitting diode (LED) was reported by O.V. Losev in 1927. Not until the birth of semiconductor...

  18. Maintenance Practices for LED Streetlights

    Broader source: Energy.gov [DOE]

    This April 14, 2014 webinar answered important questions about the maintenance and reliability of LED streetlights, and how to take these issues into account when planning and preparing for a...

  19. Development of an actuated traffic control process utilizing real-time estimated volume feedbback

    E-Print Network [OSTI]

    Pacelli, Michael Joseph

    1999-01-01T23:59:59.000Z

    state of the system in the same units. The goal of this research was to develop an actuated traffic control process that could use estimated volumes in order to optimally operate the traffic signal in real- time in response to actual traffic demands...

  20. LED Lighting Facts®

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED Lighting Facts LEDLED

  1. Modeling Traffic Flow Emissions

    E-Print Network [OSTI]

    Cappiello, Alessandra

    2002-09-17T23:59:59.000Z

    The main topic of this thesis is the development of light-duty vehicle dynamic emission models and their integration with dynamic traffic models. Combined, these models

  2. LED lamp color control system and method

    DOE Patents [OSTI]

    Gaines, James; Clauberg, Bernd; Van Erp, Josephus A.M.

    2013-02-05T23:59:59.000Z

    An LED lamp color control system and method including an LED lamp having an LED controller 58; and a plurality of LED channels 60 operably connected to the LED controller 58, each of the plurality of LED channels 60 having a channel switch 62 in series with at least one shunted LED circuit 83, the shunted LED circuit 83 having a shunt switch 68 in parallel with an LED source 80. The LED controller 58 determines whether the LED source 80 is in a feedback controllable range, stores measured optical flux for the LED source 80 when the LED source 80 is in the feedback controllable range, and bypasses storing the measured optical flux when the LED source 80 is not in the feedback controllable range.

  3. Multicolor, High Efficiency, Nanotextured LEDs

    SciTech Connect (OSTI)

    Jung Han; Arto Nurmikko

    2011-09-30T23:59:59.000Z

    We report on research results in this project which synergize advanced material science approaches with fundamental optical physics concepts pertaining to light-matter interaction, with the goal of solving seminal problems for the development of very high performance light emitting diodes (LEDs) in the blue and green for Solid State Lighting applications. Accomplishments in the duration of the contract period include (i) heteroepitaxy of nitrogen-polar LEDs on sapphire, (ii) heteroepitaxy of semipolar (11{bar 2}2) green LEDs on sapphire, (iii) synthesis of quantum-dot loaded nanoporous GaN that emits white light without phosphor conversion, (iv) demonstration of the highest quality semipolar (11{bar 2}2) GaN on sapphire using orientation-controlled epitaxy, (v) synthesis of nanoscale GaN and InGaN medium, and (vi) development of a novel liftoff process for manufacturing GaN thin-film vertical LEDs. The body of results is presented in this report shows how a solid foundation has been laid, with several noticeable accomplishments, for innovative research, consistent with the stated milestones.

  4. Real-time analysis of aggregate network traffic for anomaly detection

    E-Print Network [OSTI]

    Kim, Seong Soo

    2005-08-29T23:59:59.000Z

    The frequent and large-scale network attacks have led to an increased need for developing techniques for analyzing network traffic. If efficient analysis tools were available, it could become possible to detect the attacks, anomalies...

  5. Hybrid Traffic Data Collection Roadmap: Pilot Procurement of Third-Party Traffic Data

    E-Print Network [OSTI]

    Alexandre, Bayen

    2013-01-01T23:59:59.000Z

    Traffic Management Systems PROBE DATA QUALITY VISUALIZATIONin Traffic Management Systems EXTEND PROBE DATA QUALITYquality, accuracy, and availability of traffic data Traffic system management

  6. Low Emission Development Strategies (LEDS): Technical, Institutional...

    Open Energy Info (EERE)

    Strategies (LEDS): Technical, Institutional and Policy Lessons Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Low Emission Development Strategies (LEDS): Technical,...

  7. A Practical Primer to LED Technology

    Broader source: Energy.gov (indexed) [DOE]

    heatsink is what allows the high flux LED to generate much more light An LED (Light Emitting Diode) consists of a chip of semiconducting material treated to create a structure...

  8. LED Watch: The Outlook for OLEDs

    Broader source: Energy.gov [DOE]

    December 2014 LED Watch: The Outlook for OLEDs James Brodrick, U.S. Department of Energy LD+A Magazine

  9. An evaluation of the operating effectiveness of a computer-controlled traffic network

    E-Print Network [OSTI]

    De Steiguer, Allen Louis

    1969-01-01T23:59:59.000Z

    on relationships whith neazby detected links and known patterns of traffic movement control. iv Acknowled ements I wish to express my gratitide to those people wi. thout whose assistance this thesis would not have seen the light of day. My deepest... system of traffic control and to compare it to several conventional types of traffic signal control; * To evaluate various detector configurations for computer- controlled networks to determine the effects of different levels of detection intensity...

  10. LUNAR SOIL SIMULATION TRAFFICABILITY PARAMETERS

    E-Print Network [OSTI]

    Rathbun, Julie A.

    LUNAR SOIL SIMULATION and TRAFFICABILITY PARAMETERS by W. David Carrier, III Lunar Geotechnical.0 RECOMMENDED LUNAR SOIL TRAFFICABILITY PARAMETERS Table 9.14 in the Lunar Sourcebook (Carrier et al. 1991, p. 529) lists the current recommended lunar soil trafficability parameters: bc = 0.017 N/cm2 bN = 35° K

  11. adaptive signal model: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Michael Richard 1990-11-13 2 UNCORRECTED 2 Stochastic adaptive control model for traffic signal systems Environmental Sciences and Ecology Websites Summary: process. The model...

  12. Dual LED/incandescent security fixture

    DOE Patents [OSTI]

    Gauna, Kevin Wayne

    2005-06-21T23:59:59.000Z

    A dual LED and incandescent security lighting system uses a hybrid approach to LED illumination. It combines an ambient LED illuminator with a standard incandescent lamp on a motion control sensor. The LED illuminator will activate with the onset of darkness (daylight control) and typically remain on during the course of the night ("always on"). The LED illumination, typically amber, is sufficient to provide low to moderate level lighting coverage to the wall and ground area adjacent to and under the fixture. The incandescent lamp is integrated with a motion control circuit and sensor. When movement in the field of view is detected (after darkness), the incandescent lamp is switched on, providing an increased level of illumination to the area. Instead of an "always on" LED illuminator, the LEDs may also be switched off when the incandescent lamp is switched on.

  13. The light-emitting diode (LED) is an fairly new kind of light source found currently in

    E-Print Network [OSTI]

    The light-emitting diode (LED) is an fairly new kind of light source found currently in only a few applications, such as traffic lights and exit signs. As a relatively untested technology, luminaire this technology an ideal replacement for less efficient incandescent light sources, particularly in applications

  14. LED Linear Lamps and Troffer Lighting

    Broader source: Energy.gov [DOE]

    The CALiPER program performed a series of investigations on linear LED lamps. Each report in the series covers the performance of up to 31 linear LED lamps, which were purchased in late 2012 or 2013. The first report focuses on bare lamp performance of LED T8 replacement lamps and subsequent reports examine performance in various troffers, as well as cost-effectiveness. There is also a concise guidance document that describes the findings of the Series 21 studies and provides practical advice to manufacturers, specifiers, and consumers (Report 21.4: Summary of Linear (T8) LED Lamp Testing , 5 pages, June 2014).

  15. LED Replacements for Linear Fluorescent Lamps Webcast

    Broader source: Energy.gov [DOE]

    In this June 20, 2011 webcast on LED products marketed as replacements for linear fluorescent lamps, Jason Tuenge of the Pacific Northwest National Laboratory (PNNL) discussed current Lighting...

  16. LED Street Lighting Conversion Workshop Presentations

    Broader source: Energy.gov [DOE]

    This page provides links to the presentations given at the National League of Cities Mobile Workshop, LED Street Lighting Conversion: Saving Your Community Money, While Improving Public Safety,...

  17. Sandia National Laboratories: high-brightness LED

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Partnership, Research & Capabilities, Solid-State Lighting Solid state lighting (SSL), which uses light-emitting diodes (LEDs), has the potential to be 10 times more energy...

  18. Sandia National Laboratories: efficient LED lighting

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Partnership, Research & Capabilities, Solid-State Lighting Solid state lighting (SSL), which uses light-emitting diodes (LEDs), has the potential to be 10 times more energy...

  19. Challenges in LED Research and Development

    Broader source: Energy.gov [DOE]

    View the video about LED lighting technology, where it is headed, and the DOE’s role in its continued R&D.

  20. Municipal Consortium LED Street Lighting Workshop Presentations...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Controls Norma Isahakian, City of Los Angeles Bureau of Street Lighting San Jose's "Smart" LED Streetlights: Controlled Amy Olay, City of San Jose Adaptive Lighting Controls...

  1. EECBG Success Story: Getting Traffic Lights Talking to Improve...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Traffic Lights Talking to Improve Topeka's Traffic Tunnel EECBG Success Story: Getting Traffic Lights Talking to Improve Topeka's Traffic Tunnel October 8, 2010 - 11:16am Addthis...

  2. Traffic Dynamic Instability

    E-Print Network [OSTI]

    Louis Reese; Anna Melbinger; Erwin Frey

    2015-05-05T23:59:59.000Z

    Here we study a driven lattice gas model for microtubule depolymerizing molecular motors, where traffic jams of motors induce stochastic switching between microtubule growth and shrinkage. We term this phenomenon \\enquote{traffic dynamic instability} because it is reminiscent of microtubule dynamic instability [T. Mitchison and M. Kirschner, Nature 312, 237 (1984)]. The intermittent dynamics of growth and shrinking emerges from the interplay between the arrival of motors at the microtubule tip, motor induced depolymerization, and motor detachment from the tip. The switching dynamics correlates with low and high motor density on the lattice. This leads to an effectively bistable particle density in the system. A refined domain wall theory predicts this transient appearance of different phases in the system. The theoretical results are supported by stochastic simulations.

  3. Traffic Dynamic Instability

    E-Print Network [OSTI]

    Reese, Louis; Frey, Erwin

    2015-01-01T23:59:59.000Z

    Here we study a driven lattice gas model for microtubule depolymerizing molecular motors, where traffic jams of motors induce stochastic switching between microtubule growth and shrinkage. We term this phenomenon \\enquote{traffic dynamic instability} because it is reminiscent of microtubule dynamic instability [T. Mitchison and M. Kirschner, Nature 312, 237 (1984)]. The intermittent dynamics of growth and shrinking emerges from the interplay between the arrival of motors at the microtubule tip, motor induced depolymerization, and motor detachment from the tip. The switching dynamics correlates with low and high motor density on the lattice. This leads to an effectively bistable particle density in the system. A refined domain wall theory predicts this transient appearance of different phases in the system. The theoretical results are supported by stochastic simulations.

  4. Evaluation of TexSIM for modeling traffic behavior at diamond interchanges

    E-Print Network [OSTI]

    Meadors, Allison Christine Cherry

    1995-01-01T23:59:59.000Z

    traffic behavior at signalized diamond interchanges. To evaluate TexSIM 2.0 for simulating and providing accurate descriptive measures of performance for pretimed and actuated diamond interchanges, model outputs were compared to field data collected from...

  5. Evaluation of traffic operations at diamond interchanges using advanced actuated control

    E-Print Network [OSTI]

    Koonce, Peter John Vincent

    1998-01-01T23:59:59.000Z

    This thesis documents an operational analysis of ographics. advanced actuated traffic control at signalized diamond interchanges. The study attempts to determine the benefits a "flexible'' phasing strategy provides to the interchange. Flexible...

  6. Solving the 'Green Gap' in LED Technology

    Broader source: Energy.gov [DOE]

    One long-standing high-priority research area for DOE is to increase the efficiency of deep green LEDs. Although most products today use phosphor conversion (PC) to produce white light from a blue LED, having a good green source could lead to color-mixed white sources that would avoid the losses associated with the PC approach.

  7. Today LED Holiday Lights, Tomorrow the World?

    SciTech Connect (OSTI)

    Gordon, Kelly L.

    2004-12-20T23:59:59.000Z

    This article for The APEM Advantage, the quarterly newsletter of the Association of Professional Energy Managers (APEM) describes the recent increase in the popularity of light emitting diode (LED) lighting and compares LED light output with that of incandescent and compact fluorescent lighting.

  8. Locally Led Conservation The Local Work Group

    E-Print Network [OSTI]

    Grants ­ Conservation Stewardship Program ­ Environmental Quality Incentive Program ­ Farm & Ranch Lands1 Locally Led Conservation & The Local Work Group Mark Habiger NRCS #12;2 What Is "Locally Led Conservation"? · Community Stakeholders ­ 1. Assessing their natural resource conservation needs ­ 2. Setting

  9. LED Light Sources for Projection Display Applications

    E-Print Network [OSTI]

    Palffy-Muhoray, Peter

    LED Light Sources for Projection Display Applications By Chenhui Peng 04-13-2012 #12;Outline · 1. · The first practical LED is in red color and it is made with gallium arsenide (GaAs). 4http://en.wikipedia.org/wiki/Light with holes and release energy in the form of photons. 5http://en.wikipedia.org/wiki/Light-emitting_diode #12

  10. Financing Guidance for LED Street Lighting Programs

    Broader source: Energy.gov [DOE]

    Financing an LED street lighting replacement program can present a hurdle for many system owners, even if the planned transition offers very favorable economics. Replacing the existing system requires a significant budget, particularly as the scope of the program increases. Cities such as Los Angeles and Seattle have invested many millions of dollars into their (very successful) LED street lighting replacement programs.

  11. Development of ZnO Based Light Emitting Diodes and Laser Diodes

    E-Print Network [OSTI]

    Kong, Jieying

    2012-01-01T23:59:59.000Z

    that UV LED and LD will replace traditional lamps and alsocolored LED as traffic signals instead of traditional lamp.

  12. Enforcing Liveness in Autonomous Traffic Management Tsz-Chiu Au

    E-Print Network [OSTI]

    Au, Tsz-Chiu

    - section Management (AIM). They showed that by leveraging the capacities of autonomous vehicles a First Come, First Served (FCFS) policy to direct autonomous vehicles through an intersection traditional traffic signals and stop signs, resulting in fuel savings since vehicles are less likely to stop

  13. High Performance Green LEDs by Homoepitaxial

    SciTech Connect (OSTI)

    Wetzel, Christian; Schubert, E Fred

    2009-11-22T23:59:59.000Z

    This work's objective was the development of processes to double or triple the light output power from green and deep green (525 - 555 nm) AlGaInN light emitting diode (LED) dies within 3 years in reference to the Lumileds Luxeon II. The project paid particular effort to all aspects of the internal generation efficiency of light. LEDs in this spectral region show the highest potential for significant performance boosts and enable the realization of phosphor-free white LEDs comprised by red-green-blue LED modules. Such modules will perform at and outperform the efficacy target projections for white-light LED systems in the Department of Energy's accelerated roadmap of the SSL initiative.

  14. An LED pulser for measuring photomultiplier linearity

    E-Print Network [OSTI]

    Friend, M; Quinn, B

    2011-01-01T23:59:59.000Z

    A light-emitting diode (LED) pulser for testing the low-rate response of a photomultiplier tube (PMT) to scintillator-like pulses has been designed, developed, and implemented. This pulser is intended to simulate 80 ns full width at half maximum photon pulses over the dynamic range of the PMT, in order to precisely determine PMT linearity. This particular design has the advantage that, unlike many LED test rigs, it does not require the use of multiple calibrated LEDs, making it insensitive to LED gain drifts. Instead, a finite-difference measurement is made using two LEDs which need not be calibrated with respect to one another. These measurements give a better than 1% mapping of the response function, allowing for the testing and development of particularly linear PMT bases.

  15. White LED with High Package Extraction Efficiency

    SciTech Connect (OSTI)

    Yi Zheng; Matthew Stough

    2008-09-30T23:59:59.000Z

    The goal of this project is to develop a high efficiency phosphor converting (white) Light Emitting Diode (pcLED) 1-Watt package through an increase in package extraction efficiency. A transparent/translucent monolithic phosphor is proposed to replace the powdered phosphor to reduce the scattering caused by phosphor particles. Additionally, a multi-layer thin film selectively reflecting filter is proposed between blue LED die and phosphor layer to recover inward yellow emission. At the end of the project we expect to recycle approximately 50% of the unrecovered backward light in current package construction, and develop a pcLED device with 80 lm/W{sub e} using our technology improvements and commercially available chip/package source. The success of the project will benefit luminous efficacy of white LEDs by increasing package extraction efficiency. In most phosphor-converting white LEDs, the white color is obtained by combining a blue LED die (or chip) with a powdered phosphor layer. The phosphor partially absorbs the blue light from the LED die and converts it into a broad green-yellow emission. The mixture of the transmitted blue light and green-yellow light emerging gives white light. There are two major drawbacks for current pcLEDs in terms of package extraction efficiency. The first is light scattering caused by phosphor particles. When the blue photons from the chip strike the phosphor particles, some blue light will be scattered by phosphor particles. Converted yellow emission photons are also scattered. A portion of scattered light is in the backward direction toward the die. The amount of this backward light varies and depends in part on the particle size of phosphors. The other drawback is that yellow emission from phosphor powders is isotropic. Although some backward light can be recovered by the reflector in current LED packages, there is still a portion of backward light that will be absorbed inside the package and further converted to heat. Heat generated in the package may cause a deterioration of encapsulant materials, affecting the performance of both the LED die and phosphor, leading to a decrease in the luminous efficacy over lifetime. Recent studies from research groups at Rensselaer Polytechnic Institute found that, under the condition to obtain a white light, about 40% of the light is transmitted outward of the phosphor layer and 60% of the light is reflected inward.1,2 It is claimed that using scattered photon extraction (SPE) technique, luminous efficacy is increased by 60%. In this project, a transparent/translucent monolithic phosphor was used to replace the powdered phosphor layer. In the normal pcLED package, the powdered phosphor is mixed with silicone either to be deposited on the top of LED die forming a chip level conversion (CLC) white LED or to be casted in the package forming a volume conversion white LED. In the monolithic phosphors there are no phosphor powder/silicone interfaces so it can reduce the light scattering caused by phosphor particles. Additionally, a multi-layer thin film selectively reflecting filter is inserted in the white LED package between the blue LED die and phosphor layer. It will selectively transmit the blue light from the LED die and reflect the phosphor's yellow inward emission outward. The two technologies try to recover backward light to the outward direction in the pcLED package thereby improving the package extraction efficiency.

  16. High Power UV LED Industrial Curing Systems

    SciTech Connect (OSTI)

    Karlicek, Robert, F., Jr; Sargent, Robert

    2012-05-14T23:59:59.000Z

    UV curing is a green technology that is largely underutilized because UV radiation sources like Hg Lamps are unreliable and difficult to use. High Power UV LEDs are now efficient enough to replace Hg Lamps, and offer significantly improved performance relative to Hg Lamps. In this study, a modular, scalable high power UV LED curing system was designed and tested, performing well in industrial coating evaluations. In order to achieve mechanical form factors similar to commercial Hg Lamp systems, a new patent pending design was employed enabling high irradiance at long working distances. While high power UV LEDs are currently only available at longer UVA wavelengths, rapid progress on UVC LEDs and the development of new formulations designed specifically for use with UV LED sources will converge to drive more rapid adoption of UV curing technology. An assessment of the environmental impact of replacing Hg Lamp systems with UV LED systems was performed. Since UV curing is used in only a small portion of the industrial printing, painting and coating markets, the ease of use of UV LED systems should increase the use of UV curing technology. Even a small penetration of the significant number of industrial applications still using oven curing and drying will lead to significant reductions in energy consumption and reductions in the emission of green house gases and solvent emissions.

  17. LED Lighting Facts | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED Lighting Facts LED

  18. Wireless sensor networks for measuring traffic

    E-Print Network [OSTI]

    Varaiya, Pravin

    Wireless sensor networks for measuring traffic University of California, Berkeley Sing Yiu Cheung, Sinem Coleri, and Pravin Varaiya 2 Outline · Traffic measurement · Wireless Sensor Networks · Vehicle wireless sensor networks compete? 7 Outline · Traffic measurement · Wireless Sensor Networks · Vehicle

  19. Artificial Immune System based urban traffic control

    E-Print Network [OSTI]

    Negi, Pallav

    2007-09-17T23:59:59.000Z

    traffic. The traffic was micro-simulated with each car on a two junction road system modeled individually. The cars themselves were programmed with 'personalities' to better simulate real traffic. A novel AIS was developed to detect, predict, and control...

  20. Traffic Safety Facts 2004

    National Nuclear Security Administration (NNSA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOn AprilAElectronic Input Options Gary L. Hirsch SNLMay 20102 HourtoTransportation TRAFFIC

  1. Decisions that led to Y-12

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    German physicists Otto Hahn and Fritz Strass- mann's claim that they had achieved nuclear fission. He led a team that included Alfred O. C. Nier who was an expert on mass...

  2. LED Essentials- Technology, Applications, Advantages, Disadvantages

    Broader source: Energy.gov [DOE]

    On October 11, 2007, Kevin Dowling, VP of Innovation for Philips Solid-State Lighting Solutions, presented a broad introduction to LED technology, and discussed the technology status, advantages...

  3. LED Color Stability: 10 Important Questions

    Broader source: Energy.gov [DOE]

    This April 15, 2014 webinar examined the causes of color shift, and took a look at existing metrics used to describe color shift/color stability in LED lighting. The lumen maintenance lifetime of...

  4. Text-Alternative Version LED Lighting Forecast

    Broader source: Energy.gov [DOE]

    The DOE report Energy Savings Forecast of Solid-State Lighting in General Illumination Applications estimates the energy savings of LED white-light sources over the analysis period of 2013 to 2030....

  5. Traffic information computing platform for big data

    SciTech Connect (OSTI)

    Duan, Zongtao, E-mail: ztduan@chd.edu.cn; Li, Ying, E-mail: ztduan@chd.edu.cn; Zheng, Xibin, E-mail: ztduan@chd.edu.cn; Liu, Yan, E-mail: ztduan@chd.edu.cn; Dai, Jiting, E-mail: ztduan@chd.edu.cn; Kang, Jun, E-mail: ztduan@chd.edu.cn [Chang'an University School of Information Engineering, Xi'an, China and Shaanxi Engineering and Technical Research Center for Road and Traffic Detection, Xi'an (China)

    2014-10-06T23:59:59.000Z

    Big data environment create data conditions for improving the quality of traffic information service. The target of this article is to construct a traffic information computing platform for big data environment. Through in-depth analysis the connotation and technology characteristics of big data and traffic information service, a distributed traffic atomic information computing platform architecture is proposed. Under the big data environment, this type of traffic atomic information computing architecture helps to guarantee the traffic safety and efficient operation, more intelligent and personalized traffic information service can be used for the traffic information users.

  6. Experiment on ATM traffic analysis

    E-Print Network [OSTI]

    Liang, Chai

    1997-01-01T23:59:59.000Z

    efficiently utilizing the underlying network resources, one must have some proper methods to analyze the performance of the ATM network. In this thesis, we studied the traffic characteristics in the ATM networks and the traffic modeling. To do this, we used...

  7. LEDS GP Success Story: Fostering Coordinated LEDS Support in Kenya (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-03-01T23:59:59.000Z

    The LEDS Global Partnership (LEDS GP) strives to advance climate-resilient, low-emission development through catalyzing collaboration, information exchange, and action on the ground. The Government of Kenya is a key LEDS GP member and offers an inspiring example of how LEDS GP is having an impact globally. The 2012 LEDS Collaboration in Action workshop in London provided an interactive space for members to share experiences on cross-ministerial LEDS leadership and to learn about concrete development impacts of LEDS around the world. Inspired by these stories, the Kenya's Ministry of State for Planning, National Development and Vision 2030 (MPND) began to collaborate closely with the Ministry of Environment and Mineral Resources to create strong links between climate change action and development in the country, culminating in the integration of Kenya's National Climate Change Action Plan and the country's Medium Term Development Plan.

  8. U.S. Department of Energy NEPA Categorical Exclusion Determination...

    Broader source: Energy.gov (indexed) [DOE]

    replacements); 3) replacement of incandescent pedestrian signal heads with light-emitting diode (LED) pedestrian signals and traffic signal retrofits to LED; and 4) connection...

  9. CX-008898: Categorical Exclusion Determination | Department of...

    Broader source: Energy.gov (indexed) [DOE]

    replacements); 3) replacement of incandescent pedestrian signal heads with light-emitting diode (LED) pedestrian signals and traffic signal retrofits to LED; and 4) connection...

  10. Pittsburgh LED Street Lighting Research Project Performance Criteria

    Broader source: Energy.gov [DOE]

    A Pittsburgh LED Street Lighting Research Project document on Technical and Aesthetic Performance for Business District LED Lighting.

  11. EVALUATION OF POTENTIAL TRANSIT SIGNAL PRIORITY BENEFITS ALONG A FIXED-TIME SIGNALIZED ARTERIAL

    E-Print Network [OSTI]

    Rakha, Hesham A.

    corridor, in Arlington, Virginia. The study uses the INTEGRATION microscopic traffic simulation model buses along the arterial, and to all buses within the study corridor. The priority logic that is considered in the study provides simple green extensions and green recalls within a fixed-time traffic signal

  12. LED Lighting Forecast | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED Lighting Facts

  13. LED Outdoor Area Lighting Fact Sheet

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED LightingOutdoor Area

  14. A FLEXIBLE MODEL FOR TRAFFIC SIMULATION AND

    E-Print Network [OSTI]

    Sanner, Scott

    accurate prediction of macroscopic traffic flows (in con- sistent with kinematic wave theory) under all

  15. LED structure with enhanced mirror reflectivity

    DOE Patents [OSTI]

    Bergmann, Michael; Donofrio, Matthew; Heikman, Sten; Schneider, Kevin S; Haberern, Kevin W; Edmond, John A

    2014-04-01T23:59:59.000Z

    Embodiments of the present invention are generally related to LED chips having improved overall emission by reducing the light-absorbing effects of barrier layers adjacent mirror contacts. In one embodiment, a LED chip comprises one or more LEDs, with each LED having an active region, a first contact under the active region having a highly reflective mirror, and a barrier layer adjacent the mirror. The barrier layer is smaller than the mirror such that it does not extend beyond the periphery of the mirror. In another possible embodiment, an insulator is further provided, with the insulator adjacent the barrier layer and adjacent portions of the mirror not contacted by the active region or by the barrier layer. In yet another embodiment, a second contact is provided on the active region. In a further embodiment, the barrier layer is smaller than the mirror such that the periphery of the mirror is at least 40% free of the barrier layer, and the second contact is below the first contact and accessible from the bottom of the chip.

  16. LEDs for Energy Efficient Greenhouse Lighting

    E-Print Network [OSTI]

    Singh, Devesh; Meinhardt-Wollweber, Merve; Roth, Bernhard

    2014-01-01T23:59:59.000Z

    Light energy is an important factor for plant growth. In regions where the natural light source, i.e. solar radiation, is not sufficient for growth optimization, additional light sources are being used. Traditional light sources such as high pressure sodium lamps and other metal halide lamps are not very efficient and generate high radiant heat. Therefore, new sustainable solutions should be developed for energy efficient greenhouse lighting. Recent developments in the field of light source technologies have opened up new perspectives for sustainable and highly efficient light sources in the form of light-emitting diodes, i.e. LEDs, for greenhouse lighting. This review focuses on the potential of LEDs to replace traditional light sources in the greenhouse. In a comparative economic analysis of traditional vs. LED lighting, we show that the introduction of LEDs allows reduction of the production cost of vegetables in the long-run of several years, due to the high energy efficiency, low maintenance cost and lon...

  17. Scalability of dynamic traffic assignment

    E-Print Network [OSTI]

    Wen, Yang, Ph. D. Massachusetts Institute of Technology

    2009-01-01T23:59:59.000Z

    This research develops a systematic approach to analyze the computational performance of Dynamic Traffic Assignment (DTA) models and provides solution techniques to improve their scalability for on-line applications for ...

  18. Calibration of Dynamic Traffic Assignment Models with Point-to-Point Traffic Surveillance

    E-Print Network [OSTI]

    Vaze, Vikrant

    Accurate calibration of demand and supply simulators within a dynamic traffic assignment system is critical for consistent travel information and efficient traffic management. Emerging traffic surveillance devices such as ...

  19. Calibration of dynamic traffic assignment models with point-to-point traffic surveillance

    E-Print Network [OSTI]

    Vaze, Vikrant (Vikrant Suhas)

    2007-01-01T23:59:59.000Z

    Accurate calibration of demand and supply simulators within a Dynamic Traffic Assignment (DTA) system is critical for the provision of consistent travel information and efficient traffic management. Emerging traffic ...

  20. Sustainable LED Fluorescent Light Replacement Technology

    SciTech Connect (OSTI)

    None

    2011-06-30T23:59:59.000Z

    Ilumisys and the National Center for Manufacturing Sciences (NCMS) partnered on a three-year project awarded by the United States (U.S.) Department of Energy (DOE), to quantify the impacts of LED lamps, incandescent lamps and fluorescent benchmark lamps over a product lifecycle – i.e. to develop a sustainable design and manufacturing strategy that addresses product manufacturing, use, recycling and disposal scenarios for LED-based lighting. Based on the knowledge gained from extensive product tear-down studies of fluorescent and screw-in lighting products, lifecycle assessment tools, and accelerated lifecycle testing protocols, an interactive Sustainable LED Design Guide has been developed to aid architectural and lighting designers and engineers in making design decisions that consider three important environmental impacts (greenhouse gas emissions, energy use and mercury emission) across all phases of the life of an LED lighting product. Critical information developed for the lifecycle analysis and product feature comparisons is the useful life of the lighting product as well as its performance. The Design Guide is available at www.ncms.org, and was developed based on operational and durability testing of a variety of lighting products including power consumption, light output, and useful life of a lamp in order to allow a more realistic comparison of lamp designs. This report describes the main project tasks, results and innovative features of the lifecycle assessment (LCA)-based design tools, and the key considerations driving the sustainable design of LED lighting systems. The Design Guide incorporates the following three novel features for efficiently evaluating LED lighting features in value-chains: • Bill-of-Materials (BOM) Builder – Designers may import process data for each component and supply functional data for the product, including power, consumption, lumen output and expected useful life. • Environmental Impact Review – Designs are comparable across lifecycle phases, subsystems, and environmental impact category, and can be normalized to a userdefined functional unit. • Drill-down Review – These provide an indepth look at individual lamp designs with the ability to review across subsystem or lifecycle phase.

  1. Low-Cost Illumination-Grade LEDs

    SciTech Connect (OSTI)

    Epler, John

    2013-08-31T23:59:59.000Z

    Solid State Lighting is a cost-effective, energy-conserving technology serving a rapidly expand- ing multi-billion dollar market. This program was designed to accelerate this lighting revolution by reducing the manufacturing cost of Illumination-Grade LEDs. The technical strategy was to investigate growth substrate alternatives to standard planar sapphire, select the most effective and compatible option, and demonstrate a significant increase in Lumen/$ with a marketable LED. The most obvious alternate substrate, silicon, was extensively studied in the first two years of the program. The superior thermal and mechanical properties of Si were expected to improve wavelength uniformity and hence color yield in the manufacture of high-power illumination- grade LEDs. However, improvements in efficiency and epitaxy uniformity on standard c-plane sapphire diminished the advantages of switching to Si. Furthermore, the cost of sapphire decreased significantly and the cost of processing Si devices using our thin film process was higher than expected. We concluded that GaN on Si was a viable technology but not a practical option for Philips Lumileds. Therefore in 2012 and 2013, we sought and received amendments which broadened the scope to include other substrates and extended the time of execution. Proprietary engineered substrates, off-axis (non-c-plane) sapphire, and c-plane patterned sapphire substrates (PSS) were all investigated in the final 18 months of this program. Excellent epitaxy quality was achieved on all three candidates; however we eliminated engineered substrates and non-c-plane sapphire because of their higher combined cost of substrate, device fabrication and packaging. Ultimately, by fabricating a flip-chip (FC) LED based upon c-plane PSS we attained a 42% reduction in LED manufacturing cost relative to our LUXEON Rebel product (Q1-2012). Combined with a flux gain from 85 to 102 Lm, the LUXEON Q delivered a 210% increase in Lm/$ over this time period. The technology was commercialized in our LUXEON Q product in Sept., 2013. Also, the retention of the sapphire increased the robustness of the device, enabling sales of low-cost submount-free chips to lighting manufacturers. Thus, blue LED die sales were initiated in the form of a PSS-FC in February, 2013.

  2. Series Input Modular Architecture for Driving Multiple LEDs

    E-Print Network [OSTI]

    , where each cell drives four 700 mA LEDs. Keywords ­ solid-state lighting, light emitting diodes, LED have been achieved over the past decade in solid state light emitting diodes (LEDs), leading to high

  3. Demonstration Assessment of Light Emitting Diode (LED) Street...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Demonstration Assessment of Light Emitting Diode (LED) Street Lighting, Final Report Demonstration Assessment of Light Emitting Diode (LED) Street Lighting, Final Report This...

  4. Demonstration Assessment of Light-Emitting Diode (LED) Freezer...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Demonstration Assessment of Light-Emitting Diode (LED) Freezer Case Lighting Demonstration Assessment of Light-Emitting Diode (LED) Freezer Case Lighting This document is a report...

  5. (Expired) Nationwide Limited Public Interest Waiver for LED Lighting...

    Energy Savers [EERE]

    (Expired) Nationwide Limited Public Interest Waiver for LED Lighting and HVAC Units: February 11, 2010 (Expired) Nationwide Limited Public Interest Waiver for LED Lighting and HVAC...

  6. Energy Department Announces New University-Led Projects to Create...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    University-Led Projects to Create More Efficient, Lower Cost Concentrating Solar Power Systems Energy Department Announces New University-Led Projects to Create More Efficient,...

  7. Research Led by Sandia Reveals Leading-Edge Erosion Significantly...

    Broader source: Energy.gov (indexed) [DOE]

    Research Led by Sandia Reveals Leading-Edge Erosion Significantly Reduces Wind Turbine Performance Research Led by Sandia Reveals Leading-Edge Erosion Significantly Reduces Wind...

  8. Optically isolated signal coupler with linear response

    DOE Patents [OSTI]

    Kronberg, James W. (Aiken, SC)

    1994-01-01T23:59:59.000Z

    An optocoupler for isolating electrical signals that translates an electrical input signal linearly to an electrical output signal. The optocoupler comprises a light emitter, a light receiver, and a light transmitting medium. The light emitter, preferably a blue, silicon carbide LED, is of the type that provides linear, electro-optical conversion of electrical signals within a narrow wavelength range. Correspondingly, the light receiver, which converts light signals to electrical signals and is preferably a cadmium sulfide photoconductor, is linearly responsive to light signals within substantially the same wavelength range as the blue LED.

  9. Dion and Rakha 1 INTEGRATING TRANSIT SIGNAL PRIORITY WITHIN ADAPTIVE

    E-Print Network [OSTI]

    Rakha, Hesham A.

    Pike. The priority logic considered in the study provides simple green extensions and green recalls, Virginia as an evaluation case study. Using the INTEGRATION microscopic traffic simulation model, traffic the detection of an approaching bus. The two most common adjustments constitute green signal extensions

  10. LED North America - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9 5 - -/e),,s - 1 2 3 4 5 6 7 8 9LDRD, What doesLED

  11. White LED with High Package Extraction Efficiency

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItem Not Found Item Not Found The item youTheWSRC-TR-97-0100WHITE LED WITH HIGH PACKAGE

  12. SemiLEDs | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-f < RAPID‎ |Rippey JumpAir JumpCalifornia | OpenSelawik|SemiLEDs Jump

  13. SunLed Technologies | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro Industries PvtStratosolar Jump to: navigation,SunElectra Jump to: navigation,SunLed

  14. Recessed LED Downlights | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn'tOrigin of ContaminationHubs+18, 2012 Qualified11Department ofMeetingSynthetic DieselRecessed LED

  15. Built Environmental Correlates of Traffic Collisions 

    E-Print Network [OSTI]

    Yu, Chia-Yuan

    2014-07-01T23:59:59.000Z

    Traffic safety has become an important concern in recent years. Built environmental characteristics have been identified as a critical factor in affecting traffic safety. However, several research gaps remain in the ...

  16. Fermilab | Traffic Safety at Fermilab |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.New Mexico Feb. 13, 2013FocusreceivesTraffic Safety Traffic

  17. DATALITE: a Distributed Architecture for Traffic Analysis via Light-weight Traffic Digest

    E-Print Network [OSTI]

    Chao, Jonathan

    DATALITE: a Distributed Architecture for Traffic Analysis via Light-weight Traffic Digest for Traffic Analysis via LIght- weight Traffic digEst, which introduces a set of new distributed algorithms digests (TD's) amongst the network nodes. A TD for N packets only requires O(loglog N) bits of memory

  18. FAA Air Traffic Organization Safety Management

    Broader source: Energy.gov [DOE]

    Presenter: Mark DeNicuolo, Manager Performance and Analyses Air Traffic Organization Safety and Technical Training Federal Aviation Administration

  19. New and Underutilized Technology: High Bay LED Lighting

    Broader source: Energy.gov [DOE]

    The following information outlines key deployment considerations for high bay LED lighting within the Federal sector.

  20. Text-Alternative Version: LED Essentials- Technology, Applications, Advantages, Disadvantages

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the LED Essentials - Technology, Applications, Advantages, Disadvantages webcast.

  1. 2001 TRAFFIC ZONE BOUNDARIES Zone Numbers

    E-Print Network [OSTI]

    Toronto, University of

    2001 TRAFFIC ZONE BOUNDARIES Zone Numbers & Detailed Definitions #12;2001 TRAFFIC ZONE BOUNDARIES of Toronto Joint Program in Transportation January 2003 #12;PREFACE This report presents the 2001 traffic zone numbers by local municipalities in the 2001 TTS survey area. The second part presents detailed

  2. May 21, 2014 Local Agency Traffic

    E-Print Network [OSTI]

    Minnesota, University of

    Field Evaluation Traffic Data Collection Processes Study Is there better EQUIPMENT for collecting low Improvements Field Evaluation Traffic Data Collection Processes Study Is there better EQUIPMENT for collecting;Project Overview 2013-2014Local Agency Data Collection 5 · Tested traffic sensors in a low

  3. The International Symposium on Transportation and Traffic Theory 00 (2013) 119 Linear-Quadratic Model Predictive Control

    E-Print Network [OSTI]

    Nazarathy, Yoni

    2013-01-01T23:59:59.000Z

    al., 1996). The more recent works on traffic control systems have adopted results of modern control responsibility of Delft University of Technology Keywords: Model Predictive Control, Intelligent Transport System, Congestion Control 1. Introduction Increasing population and economic activities in modern societies have led

  4. Regenerative braking on bicycles to power LED safety flashers

    E-Print Network [OSTI]

    Collier, Ian M

    2005-01-01T23:59:59.000Z

    This work develops a method for capturing some of the kinetic energy ordinarily lost during braking on bicycles to power LED safety flashers. The system is designed to eliminate: (a) battery changing in popular LED flashers, ...

  5. Building highly efficient LEDs in the yellow-green spectrum

    SciTech Connect (OSTI)

    None

    2012-01-01T23:59:59.000Z

    Argonne and Purdue researchers are peering deep into the atomic structure and composition of LED lights in order to build highly efficient LEDs in the yellow-green spectrum.

  6. EECBG Success Story: Small Nebraska Town Welcomes LEDs and Energy...

    Broader source: Energy.gov (indexed) [DOE]

    historic square, built in the 1850's, is about to become home to something new: LED lights. Learn more. Addthis Related Articles Tecumseh is installing 95 new LED light fixtures...

  7. LED Manufacturing Process Modifications Will Boost Quality and

    E-Print Network [OSTI]

    2012 The Issue Highly energyefficient LightEmitting Diode (LED) lighting products have made great process that will enable LED manufacturers to produce higher quality, energyefficient products at lower

  8. LEDs Go Ivy League: Princeton’s Dillon Gymnasium

    Broader source: Energy.gov [DOE]

    View the video about LED lighting in Dillon Gymnasium, a focal point of sports and recreation at Princeton since 1947. William Evans discusses measurable benefits of LED lighting in the gym and...

  9. Text-Alternative Version: Challenges in LED Research and Development

    Broader source: Energy.gov [DOE]

    Narrator: LEDs have made remarkable progress in the past decade and gained a strong foothold in the US marketplace. In 2012, LED lighting saved an estimated 71 trillion BTUs, equivalent to annual...

  10. Text-Alternative Version: LED Replacements for Linear Fluorescent Lamps

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the "LED Replacements for Linear Fluorescent Lamps" webcast, held June 20, 2011.

  11. Text-Alternative Version: LEDs for Interior Office Applications

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the LEDs for Interior Office Applications webcast, held March 18, 2010.

  12. Text-Alternative Version: Evaluating LED Street Lighting Solutions

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the Evaluating LED Street Lighting Solutions webcast, held July 20, 2010.

  13. Mann LED Elevator Ligh ng: ECI Savings Table Cost (billed)

    E-Print Network [OSTI]

    Lipson, Michal

    the elevators, deter mined an LED replace ment lamp for the ex is ng halogen lamps, cal culated a cost benefitMann LED Elevator Ligh ng: ECI Savings Table Utility Historical Energy Use (MMBtu) Est. FY 2012,000 2 Energy Conservation Initiative (ECI) Project Summary Mann LED Elevator Ligh ng, Facility 1027 Mann

  14. Characterization of failure modes in deep UV and deep green LEDs utilizing advanced semiconductor localization techniques.

    SciTech Connect (OSTI)

    Tangyunyong, Paiboon; Miller, Mary A.; Cole, Edward Isaac, Jr.

    2012-03-01T23:59:59.000Z

    We present the results of a two-year early career LDRD that focused on defect localization in deep green and deep ultraviolet (UV) light-emitting diodes (LEDs). We describe the laser-based techniques (TIVA/LIVA) used to localize the defects and interpret data acquired. We also describe a defect screening method based on a quick electrical measurement to determine whether defects should be present in the LEDs. We then describe the stress conditions that caused the devices to fail and how the TIVA/LIVA techniques were used to monitor the defect signals as the devices degraded and failed. We also describe the correlation between the initial defects and final degraded or failed state of the devices. Finally we show characterization results of the devices in the failed conditions and present preliminary theories as to why the devices failed for both the InGaN (green) and AlGaN (UV) LEDs.

  15. Capacity-aware back-pressure traffic signal control

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    load, one must wonder whether the network is used at its maximum capacity. Vehicle automation is expected to enable much more precise and intelligent coordination between vehicles, possibly reducing congestion [1]. However, automated cars are not currently ready for large commercial deployment. Human

  16. Ohio Town Installing 'Green' Traffic Signals | Department of...

    Broader source: Energy.gov (indexed) [DOE]

    success. | Photo Courtesy of Flickr user mjasonprickett David Crockett, Chattanooga's Green Frontiersman EAA Executive Director Luis Bernal addresses an audience about Puerto...

  17. Freeway Short-Term Traffic Flow Forecasting by Considering Traffic Volatility Dynamics and Missing Data Situations

    E-Print Network [OSTI]

    Zhang, Yanru

    2012-10-19T23:59:59.000Z

    , assuming constant variance when perform forecasting. This method does not consider the volatility nature of traffic flow data. This paper demonstrated that the variance part of traffic flow data is not constant, and dependency exists. A volatility model...

  18. Cree Sets New Benchmarks for LED Efficacy and Brightness

    Broader source: Energy.gov [DOE]

    Cree has successfully created a cool white LED prototype that delivers 107 lm/W at 350mA. This achievement builds on the Cree EZBright® LED chip platform, developed in part with prior funding support from DOE. Cree made the prototype LED under their DOE project focused on developing LED chips incorporating photonic crystal elements for improved light extraction and novel package technology for higher down-conversion efficiency compared to conventional LEDs. Based on a 1 millimeter-square chip, the new prototype LED produces white light with a CCT of 5500K and a CRI of 73. Integration of four of these prototype LEDs can produce luminous flux of more than 450 lumens.

  19. Test instances for the traffic assignment problem

    E-Print Network [OSTI]

    2008-01-08T23:59:59.000Z

    Jan 8, 2008 ... mation on test problems previously used in the literature to facilitate benchmarking. Keywords. Traffic assignment problem, BPR function, ...

  20. A Kinematic Wave Traffic Flow Model for Mixed Traffic H. M. Zhang1

    E-Print Network [OSTI]

    Mease, Kenneth D.

    A Kinematic Wave Traffic Flow Model for Mixed Traffic H. M. Zhang1 Department of Civil-mail: wjin@ucdavis.edu ABSTRACT In this paper we extend the Lighthill-Whitham-Richards kinematic wave traffic kinematic wave model developed by Lighthill, Whitham (3) and Richards (4): t+(V())x=0, V( )Q(). (3

  1. Addendum to 2010 NREL Environmental Performance Report ? Traffic...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Update November 2011 Page 1 of 4 Traffic Mitigation Action Plan 2010 Update Traffic Management A Mitigation Action Plan (MAP), finalized in May 2008, was developed to address...

  2. Impact of Traffic States on Freeway Collision Frequency

    E-Print Network [OSTI]

    Yeo, Hwasoo; Jang, Kitae; Skabardonis, Alexander

    2010-01-01T23:59:59.000Z

    interurban motorways, Accident Analysis and Prevention, 34,of traffic flow, Accident Analysis and Prevention, 36, 2004,hourly traffic flow-I: Accident Analysis and Prevention, 14,

  3. Network Traffic Analysis and SCADA Security

    E-Print Network [OSTI]

    Hu, Jiankun

    systems are widely used for monitoring and controlling industrial systems including power plants, water of traffic generated. Finally, network traffic monitoring can be used in security management to identify the vulnerabilities of SCADA systems because this 383 © Springer 2010 , Handbook of Information and Communication

  4. Approaching Real-time Network Traffic Classification

    E-Print Network [OSTI]

    Haddadi, Hamed

    and studies. It serves as the input for Intrusion Detection Systems, provides Class-of-Service (CoS) mapping22 Approaching Real-time Network Traffic Classification ISSN 1470-5559 RR-06-12 October 2006-time Network Traffic Classification Wei Li, Kaysar Abdin, Robert Dann and Andrew Moore Department of Computer

  5. New GATEWAY Report Monitors LED System Performance in a High...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    the light. The Yuma site is an extreme environment: high ambient temperatures and direct solar radiation heat up the luminaires throughout the day, and at sunset the LED...

  6. To Bridge LEDs' Green Gap, Scientists Think Small

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    where LED efficiency plunges, simulations at the U.S. Department of Energy's National Energy Research Scientific Computing Center (NERSC) have shown. Using NERSC's Cray XC30...

  7. LED Luminaire Lifetime: Recommendations for Testing and Reporting

    Broader source: Energy.gov (indexed) [DOE]

    product life, and many relied on the gradual lumen depreciation of the LED (light-emitting diode) source as the best indicator- resulting, on occasion, in unrealistic claims...

  8. LED Provides Effective and Efficient Parking Area Lighting at...

    Broader source: Energy.gov (indexed) [DOE]

    White Light Options for Parking Area Lighting Demonstration Assessment of Light Emitting Diode (LED) Street Lighting, Final Report Guide to FEMP-Designated Parking Lot...

  9. The City of Los Angeles LED Streetlight Program

    Broader source: Energy.gov [DOE]

    View the video about the Los Angeles LED streetlight program, featuring an interview with City of Los Angeles Bureau of Street Lighting Director, Ed Ebrahimian.

  10. ORNL-led team demonstrates desalination with nanoporous graphene...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Communications 865.576.6448 ORNL-led team demonstrates desalination with nanoporous graphene membrane Researchers created nanopores in graphene (red, and enlarged in the circle...

  11. Article Published on LED Lumen Maintenance and Light Loss Factors...

    Broader source: Energy.gov (indexed) [DOE]

    of a comprehensive lifetime rating - as well as the problematic relationship between SSL lifetime and lumen maintenance - determining an appropriate LLD factor for LED products...

  12. CBEA LED Site Lighting Specification - Version 1.3, Released...

    Energy Savers [EERE]

    Applications Outdoor Area Lighting Home About the Solid-State Lighting Program R&D Program Market-Based Programs SSL Basics Using LEDs Information Resources Financial Opportunities...

  13. Lighting the Great Outdoors: LEDs in Exterior Applications

    SciTech Connect (OSTI)

    Cook, Tyson D. S.; Bryan, Mary M.; Kinzey, Bruce R.; Myer, Michael

    2008-08-17T23:59:59.000Z

    Recent progress in the development of white light LEDs promises great impact by opening up the huge potential for LED illumination in new areas. One such area is general illumination for exterior applications. For example, there are an estimated combined 60.5 million roadway and parking installations in the U.S. These lights account for an estimated 53.3 TWh of electricity usage annually -- nearly 7% of all lighting. If LEDs could provide the same light performance with just 25% greater efficiency, savings of over 13 TWh could be achieved. In 2007, the authors assessed emerging LED lighting technologies in a parking garage and on a city street. The purpose of these tests was to enable a utility to determine whether energy efficiency programs promoting white light LED products might be justified. The results have supported the great promise of LEDs in exterior applications, while also highlighting the barriers that continue to hinder their widespread adoption. Such barriers include 1) inconsistent product quality across manufacturers; 2) lack of key metrics for comparing LEDs to conventional sources; and 3) high upfront cost of LED luminaires compared to conventional luminaires. This paper examines these barriers, ways in which energy-efficiency programs could help to overcome them, and the potential for energy and financial savings from LED lighting in these two exterior applications.

  14. LEDs Go Ivy League: Princeton University and DOE GATEWAY Demonstrations

    Broader source: Energy.gov [DOE]

    View the video about LED lighting at Princeton University, which has dramatically reduced energy costs in a number of installations around campus. William Evans, electrical engineer, describes the...

  15. Adopting LED Technology: What Federal Facility Managers Need to Know

    Broader source: Energy.gov [DOE]

    This document describes the presentation slides for the "Adopting LED Technology: What Federal Facility Managers Need to Know" webinar that took place on September 11, 2014.

  16. Cooking Up New Nanoribbons to Make Better White LEDs | Advanced...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    appealing white phosphors based on LEDs. The materials combine the rare-earth element europium with aluminum oxide to form europium aluminate nanoribbons. Powders of europium oxide...

  17. Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting at the I-35W Bridge, Minneapolis, MN

    SciTech Connect (OSTI)

    Kinzey, Bruce R.; Myer, Michael

    2009-08-31T23:59:59.000Z

    This report describes the process and results of a demonstration of solid-state lighting (SSL) technology conducted in 2009 at the recently reconstructed I-35W bridge in Minneapolis, MN. The project was supported under the U.S. Department of Energy (DOE) Solid-State Lighting GATEWAY Technology Demonstration Program. Other participants in the demonstration project included the Minnesota Department of Transportation (Mn/DOT), Federal Highways Administration (FHWA), and BetaLED™ (a division of Ruud Lighting). Pacific Northwest National Laboratory (PNNL) conducted the measurements and analysis of the results. DOE has implemented a three-year evaluation of the LED luminaires in this installation in order to develop new longitudinal field data on LED performance in a challenging, real-world environment. This document provides information through the initial phase of the I-35W bridge project, up to and including the opening of the bridge to the public and the initial feedback received on the LED lighting installation from bridge users. Initial findings of the evaluation are favorable, with minimum energy savings level of 13% for the LED installation relative to the simulated base case using 250W high-pressure sodium (HPS) fixtures. The LEDs had an average illuminance level of 0.91 foot candles compared to 1.29 fc for the HPS lamps. The LED luminaires cost $38,000 more than HPS lamps, yielding a lengthy payback period, however the bridge contractor had offered to include the LED luminaires as part of the construction package at no additional cost. One potentially significant benefit of the LEDs in this installation is avoiding rolling lane closures on the heavily-traveled interstate bridge for the purpose of relamping the HPS fixtures. Rolling lane closures involve multiple crew members and various maintenance and safety vehicles, diversion of traffic, as well as related administrative tasks (e.g., approvals, scheduling, etc.). Mn/DOT records show an average cost of relamping fixtures along interstate roadways of between $130-150 per pole. The previous bridge saw a lamp mortality rate of approximately 50% every two years, though the new bridge was designed to minimize many of the vibration issues. A voluntary Web-based feedback survey of nearly 500 self-described bridge users showed strong preference for the LED lighting - positive comments outnumbered negative ones by about five-to-one.

  18. Autonomous Traffic Control System Using Agent Based Technology

    E-Print Network [OSTI]

    M, Venkatesh; V, Srinivas

    2011-01-01T23:59:59.000Z

    The way of analyzing, designing and building of real-time projects has been changed due to the rapid growth of internet, mobile technologies and intelligent applications. Most of these applications are intelligent, tiny and distributed components called as agent. Agent works like it takes the input from numerous real-time sources and gives back the real-time response. In this paper how these agents can be implemented in vehicle traffic management especially in large cities and identifying various challenges when there is a rapid growth of population and vehicles. In this paper our proposal gives a solution for using autonomous or agent based technology. These autonomous or intelligent agents have the capability to observe, act and learn from their past experience. This system uses the knowledge flow of precedent signal or data to identify the incoming flow of forthcoming signal. Our architecture involves the video analysis and exploration using some Intelligence learning algorithm to estimate and identify the...

  19. An approach to closed network signal coordination

    E-Print Network [OSTI]

    Dutt, Amitabh K

    1971-01-01T23:59:59.000Z

    for traffic signal coordination in a closed signal system in order to improve the quality of flow. Three methods have been developed. The first one, the method of independent link analysis is based on the assumption that delay in a link depends solely... on the offset between the settir gs of the signal at each end of the link and independent of any other signal setting in the network. The second method is based on a set of time reference equations. This method is very useful in situations where the link...

  20. LED Chips and Packaging for 120 LPW SSL Component

    SciTech Connect (OSTI)

    James Ibbetson

    2009-09-30T23:59:59.000Z

    Cree has developed a new, high-efficiency, low-cost, light emitting diode (LED) lamp module that should be capable of replacing standard, halogen, fluorescent and metal halide lamps based on the total cost of ownership. White LEDs are produced by combining one or more saturated color LEDs with a phosphor or other light down-converting media to achieve white broad-band illumination. This two year project addressed LED chip and package efficiency improvements to establish a technology platform suitable for low-cost, high-efficiency commercial luminaires. Novel photonic-crystal LEDs were developed to improve the light extraction efficiency of blue GaN-based LEDs compared to the baseline technology. Improved packaging designs that reduced down-conversion and absorption related light losses, led to a higher overall LED efficiency. Specifically, blue LEDs were demonstrated with light output nearing 600 mW and an external quantum efficiency greater than 60 percent (using 1 mm2 chips at an operating current of 350 mA). The results were achieved using a novel, production capable photonic-crystal LED fabrication process. These LEDs formed the basis for a multi-chip white lamp module prototype, which provided 510 lumens light output at a correlated color temperature (CCT) of 3875 K and an operating current of 350 mA per 1mm2 chip. The overall conversion efficiency at 4100 K improved to ~ 65%. The resulting efficacy is 112 lumens per watt (LPW) â?? a 33% improvement over the start of the project. In addition, a proof-of-concept luminaire was demonstrated that provided a flux of 1700 lumens at a 3842 K CCT.

  1. Low Cost Lithography Tool for High Brightness LED Manufacturing

    SciTech Connect (OSTI)

    Andrew Hawryluk; Emily True

    2012-06-30T23:59:59.000Z

    The objective of this activity was to address the need for improved manufacturing tools for LEDs. Improvements include lower cost (both capital equipment cost reductions and cost-ofownership reductions), better automation and better yields. To meet the DOE objective of $1- 2/kilolumen, it will be necessary to develop these highly automated manufacturing tools. Lithography is used extensively in the fabrication of high-brightness LEDs, but the tools used to date are not scalable to high-volume manufacturing. This activity addressed the LED lithography process. During R&D and low volume manufacturing, most LED companies use contact-printers. However, several industries have shown that these printers are incompatible with high volume manufacturing and the LED industry needs to evolve to projection steppers. The need for projection lithography tools for LED manufacturing is identified in the Solid State Lighting Manufacturing Roadmap Draft, June 2009. The Roadmap states that Projection tools are needed by 2011. This work will modify a stepper, originally designed for semiconductor manufacturing, for use in LED manufacturing. This work addresses improvements to yield, material handling, automation and throughput for LED manufacturing while reducing the capital equipment cost.

  2. Semiconductors 4-bit I2C LED dimmer

    E-Print Network [OSTI]

    Berns, Hans-Gerd

    with SMBus · Internal power-on reset · Noise filter on SCL/SDA inputs · 4 open drain outputs directly drive for dimming LEDs in 256 discrete steps for Red/Green/Blue (RGB) color mixing and back light applications to 1.69 second. The open drain outputs directly drive the LEDs with maximum output sink current of 25 m

  3. CX-000195: Categorical Exclusion Determination | Department of...

    Broader source: Energy.gov (indexed) [DOE]

    (Energy) Manager, Conversion of County Traffic Signals to all LED (light-emitting diode) Indications, Message Display Conversion to LED, Neighborhood Energy Efficiency...

  4. CX-005699: Categorical Exclusion Determination | Department of...

    Broader source: Energy.gov (indexed) [DOE]

    code standards; 5) retrofit lights city parking lots with energy efficient light emitting diode (LED) lighting and convert traffic signals to LED fixtures; 6) replace heating,...

  5. Kinematic Wave Models of Network Vehicular Traffic Wenlong Jin

    E-Print Network [OSTI]

    Mease, Kenneth D.

    Kinematic Wave Models of Network Vehicular Traffic By Wenlong Jin B.S. (University of Science Applied Mathematics Kinematic Wave Models of Network Vehicular Traffic Abstract The kinematic wave theory vehicular traffic. In this dissertation, we study kinematic wave models of network traffic, which

  6. Structure Evolution of Dynamic Bayesian Network for Traffic Accident Detection

    E-Print Network [OSTI]

    Cho, Sung-Bae

    Structure Evolution of Dynamic Bayesian Network for Traffic Accident Detection Ju-Won Hwang, Young and the accuracy in a domain of the traffic accident detection. Keywords-structure of dynamic Bayesian network; Bayesian network, evolution I. INTRODUCTION Every year, traffic congestion and traffic accidents have been

  7. A NEW LED-LED PORTABLE CO2 GAS SENSOR BASED ON AN INTERCHANGEABLE MEMBRANE SYSTEM FOR INDUSTRIAL APPLICATIONS

    E-Print Network [OSTI]

    Lee, Hyowon

    to oxygen scavenging [5]. High CO2 levels (10- 80 %) are desirable for foods such as meat and poultryA NEW LED-LED PORTABLE CO2 GAS SENSOR BASED ON AN INTERCHANGEABLE MEMBRANE SYSTEM FOR INDUSTRIAL APPLICATIONS Abstract A new system for CO2 measurement (0-100%) by based on a paired emitter-detector diode

  8. LOW-COST LED LUMINAIRE FOR GENERAL ILLUMINATION

    SciTech Connect (OSTI)

    Lowes, Ted

    2014-07-31T23:59:59.000Z

    During this two-year Solid-State Lighting (SSL) Manufacturing R&D project Cree developed novel light emitting diode (LED) technologies contributing to a cost-optimized, efficient LED troffer luminaire platform emitting at ~3500K correlated color temperature (CCT) at a color rendering index (CRI) of >90. To successfully achieve program goals, Cree used a comprehensive approach to address cost reduction of the various optical, thermal and electrical subsystems in the luminaire without impacting performance. These developments built on Cree’s high- brightness, low-cost LED platforms to design a novel LED component architecture that will enable low-cost troffer luminaire designs with high total system efficacy. The project scope included cost reductions to nearly all major troffer subsystems as well as assembly costs. For example, no thermal management components were included in the troffer, owing to the optimized distribution of compact low- to mid-power LEDs. It is estimated that a significant manufacturing cost savings will result relative to Cree’s conventional troffers at the start of the project. A chief project accomplishment was the successful development of a new compact, high-efficacy LED component geometry with a broad far-field intensity distribution and even color point vs. emission angle. After further optimization and testing for production, the Cree XQ series of LEDs resulted. XQ LEDs are currently utilized in Cree’s AR series troffers, and they are being considered for use in other platforms. The XQ lens geometry influenced the independent development of Cree’s XB-E and XB-G high-voltage LEDs, which also have a broad intensity distribution at high efficacy, and are finding wide implementation in Cree’s omnidirectional A-lamps.

  9. Optimized Phosphors for Warm White LED Light Engines

    SciTech Connect (OSTI)

    Setlur, Anant; Brewster, Megan; Garcia, Florencio; Hill, M. Christine; Lyons, Robert; Murphy, James; Stecher, Tom; Stoklosa, Stan; Weaver, Stan; Happek, Uwe; Aesram, Danny; Deshpande, Anirudha

    2012-07-30T23:59:59.000Z

    The objective of this program is to develop phosphor systems and LED light engines that have steady-state LED efficacies (using LEDs with a 60% wall-plug efficiency) of 105–120 lm/W with correlated color temperatures (CCT) ~3000 K, color rendering indices (CRI) >85, <0.003 distance from the blackbody curve (dbb), and <2% loss in phosphor efficiency under high temperature, high humidity conditions. In order to reach these goals, this involves the composition and processing optimization of phosphors previously developed by GE in combination with light engine package modification.

  10. LED Lights for All Occasions | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED Lighting FactsLED

  11. Partitioning Complexity in Air Traffic Management Task

    E-Print Network [OSTI]

    Cummings, M. L.

    2006-01-01T23:59:59.000Z

    Cognitive complexity is a term that appears frequently in air traffic control (ATC) research literature, yet there is little principled investigation of the potential sources of cognitive complexity. Three distinctly ...

  12. On traffic analysis attacks and countermeasures

    E-Print Network [OSTI]

    Fu, Xinwen

    2007-04-25T23:59:59.000Z

    . This is true even if some commonly used countermeasures (e.g., link padding) have been deployed. We proposed an alternative effective countermeasure to counter this passive traffic analysis attack. Our extensive experimental results indicated...

  13. Development and analysis of a flexible signal phasing strategy for diamond interchange control

    E-Print Network [OSTI]

    Krueger, Gregory David

    1995-01-01T23:59:59.000Z

    There are many signal timing strategies for diamond interchanges. Due to the different geometric and traffic conditions, however, none of the available strategies is always optimal. The two most widely used strategies, three-phase, and four...

  14. The design of a microprogrammed traffic controller

    E-Print Network [OSTI]

    Tietjen, James Leslie

    1973-01-01T23:59:59.000Z

    Subject: Electrical Fngineering THE DESIGN OF A MICROPROGRAMMED TRAFFIC CONTROLLER A Thesis by JAMES LESLIE TIETJEN Approved as to style and content by: ar a o C rttee ea o epartm nt em er m er Mem er em er Mem er August 1973 ABSTRACT... The Design of a Microprogrammed Traffic Controller. (August 1973) James Leslie Tietjen, B. S, , Texas ABM 11niversity Directed By: Dr, V. Thomas Rhyne The purpose of this thesis is to design, simulate, and evaluate a microprogrammed system...

  15. http://tti.tamu.edu > Variable message signs > Traffic actuated controllers > Traffic signals > Flashing traffic signals > Lane use control signals > Road markings > Rumble strips > Warrants (Traffic control devices) > Gro

    E-Print Network [OSTI]

    agencies and private- sector companies on the design, construction, testing and evaluation of highway railings > Transportation corridors > Streambeds > Pipelin Street lighting > Freeways > Highways > Arterial > Light emitting diodes > Portable equipment > Construction equipment > Roadbuilding machinery

  16. Fuel consumption analyses for urban traffic management

    SciTech Connect (OSTI)

    Bowyer, D.P.; Akcelik, R.; Biggs, D.C.

    1986-12-01T23:59:59.000Z

    A primary output from the fuel consumption research conducted by the Australian Road Research Board (ARRB) is the ARRB Special Report, Guide to Fuel Consumption Analyses. This article briefly summarizes the background of the guide, describes its major features, and considers its relevance to urban traffic management decision. The guide was a result of a technical audit of studies relating to energy consumption in traffic and transport systems. A brief summary of the audit process and findings is given. The guide is intended primarily as an aid to effective use of fuel consumption models in the design of traffic management schemes. The forms of four interrelated fuel consumption models of the guide are described and their likely transferability to various situations is indicated. Each traffic and fuel consumption model is appropriate to a particular scale of traffic system. This link is shown for several selected traffic models. As an example, a discussion of the importance of accurate fuel consumption estimates for the case of priority control at a particular intersection is given.

  17. Team Led by Argonne National Lab Selected as DOE's Batteries...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Team Led by Argonne National Lab Selected as DOE's Batteries and Energy Storage Hub On November 30, 2012 In features Energy Department Announces Team to Receive up to 120...

  18. WEBINAR: CAN LEDS PERFORM IN A PERFORMING ARTS BUILDING? | Department...

    Broader source: Energy.gov (indexed) [DOE]

    the Nadine McGuire Theatre + Dance Pavilion at the University of Florida. Can LEDs render skin tones and makeup accurately in a dressing room? Can they provide the vertical...

  19. EECBG Success Story: Solar LED Light Pilot Project Illuminates...

    Energy Savers [EERE]

    courtesy of Lionel Green, Sand Mountain Reporter. A strip of new solar-powered light emitting-diode (LED) streetlights in Boaz, Alabama were installed with grant funds from the...

  20. MOF Coating a Promising Path to White LEDs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (MOF); the structure was determined at Beamline 11.3.1. Coating a blue light-emitting diode (LED) with this compound readily generates white light with high luminous...

  1. Text-Alternative Version: LED Color Stability Webinar

    Broader source: Energy.gov [DOE]

    Michael Royer: All right, welcome ladies and gentleman. I'm Michael Royer of Pacific Northwest National Laboratory, and I'd like to welcome you to today's webinar on LED Color Stability, Ten...

  2. Measured Off-Grid LED Lighting System Performance

    E-Print Network [OSTI]

    Granderson, Jessica

    2009-01-01T23:59:59.000Z

    Budget: The Economics of Off-Grid Lighting for SmallA. Jacobson. 2007. "The Off-Grid Lighting Market in WesternTesting for Emerging Off-grid White-LED Illumination Systems

  3. Implementing and Sustaining Operator Led Energy Efficiency Improvements

    E-Print Network [OSTI]

    Hoyle, A.; Knight, N.; Rutkowski, M.

    2011-01-01T23:59:59.000Z

    , to significantly reduce energy consumption, the site must focus on a strategic approach which involves developing, implementing and sustaining a client specific program of energy optimization. We discuss ways of sustaining energy performance through operator led...

  4. Sandia National Laboratories: AlGaAs LEDs

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    electroluminescence was first reported by H.J. Round in 1907, and the first light-emitting diode (LED) was reported by O.V. Losev in 1927. Not until the birth of semiconductor...

  5. Advances in Chip Technology, Packaging Enable White LED Breakthroughs

    Broader source: Energy.gov [DOE]

    Significant advances in chip technology have enabled Cree, Inc.'s Santa Barbara Technology Center to demonstrate white LEDs with record efficacies as high as 74 lumens per watt - on par with...

  6. Laboratory Evaluation of LED T8 Replacement Lamp Products

    SciTech Connect (OSTI)

    Richman, Eric E.; Kinzey, Bruce R.; Miller, Naomi J.

    2011-05-23T23:59:59.000Z

    A report on a lab setting analysis involving LED lamps intended to directly replace T8 fluorescent lamps (4') showing light output, power, and economic comparisons with other fluorescent options.

  7. WEBINAR: LED LIGHTING IN A PERFORMING ARTS BUILDING

    Broader source: Energy.gov [DOE]

    Can LEDs render skin tones and makeup accurately in a dressing room? Can they provide the vertical footcandles in a studio to make dancers' bodies visible, or deliver acting studio lighting to...

  8. Demonstrating LED and Fiber Optic Lighting in Commissary Applications

    Broader source: Energy.gov [DOE]

    Presentation—given at the Federal Utility Partnership Working Group (FUPWG) Fall 2008 meeting—covers goals of the project and applications for light-emitting diodes (LEDs) and fiber optic lighting.

  9. af led lyskilder: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Effective Fabrication of a Solar PV Panel for LED Lighting CiteSeer Summary: Abstract Solar cells are very fragile so they need a encapsulant and encasing for protection and...

  10. White LED Benchmark of 65 Lumens Per Watt Achieved

    Broader source: Energy.gov [DOE]

    Novel chip design and the balance of multiple interrelated design parameters have enabled Cree, Inc.'s Santa Barbara Technology Center to demonstrate white LEDs with efficacies greater than 65 lumens per watt at 350 mA. The results are particularly significant because they were achieved with a pre-production prototype chip using the same package used in Cree's commercially available XLamp® 7090 high power LED, rather than a laboratory device.

  11. Integrated LED-based luminare for general lighting

    DOE Patents [OSTI]

    Dowling, Kevin J.; Lys, Ihor A.; Roberge, Brian; Williamson, Ryan C.; Roberts, Ron; Datta, Michael; Mollnow, Tomas; Morgan, Frederick M.

    2013-03-05T23:59:59.000Z

    Lighting apparatus and methods employing LED light sources are described. The LED light sources are integrated with other components in the form of a luminaire or other general purpose lighting structure. Some of the lighting structures are formed as Parabolic Aluminum Reflector (PAR) luminaires, allowing them to be inserted into conventional sockets. The lighting structures display beneficial operating characteristics, such as efficient operation, high thermal dissipation, high output, and good color mixing.

  12. An Integrated Solid-State LED Luminaire for General Lighting

    SciTech Connect (OSTI)

    Kevin Dowling; Fritz Morgan Ihor Lys; Mike Datta; Bernd Keller; Thomas Yuan

    2009-03-31T23:59:59.000Z

    A strong systems approach to designing and building practical LED-based replacement lamps is lacking. The general method of taking high-performance LEDs and marrying them to standard printed circuit boards, drivers and a heat sink has fallen short of the promise of LED lighting. In this program, a top-down assessment of requirements and a bottom-up reinvention of LED sources, electronics, optics and mechanics have resulted in the highest performance lamp possible. The team, comprised of Color Kinetics, the leaders in LED lighting and Cree, the leaders in LED devices took an approach to reinvent the package, the driver and the overall form and aesthetic of a replacement source. The challenge was to create a new benchmark in LED lighting - the resultant lamp, a PAR38 equivalent, met the light output, color, color quality and efficacy marks set out in the program as well as being dimmable, which is important for market acceptance. The approach combined the use of multiple source die, a chip-on-board approach, a very efficient driver topology, the use of both direct emission and phosphor conversion, and a unique faceted optic to avoid the losses, artifacts and hotspots of lensed approaches. The integral heat sink provided a mechanical base and airflow using a chimney-effect for use in a wide variety of locations and orientations. These research results led to a much better understanding of the system effects of component level technologies. It was clear that best-of-breed sub-system results do not necessarily result in the best end result for the complete system. In doing this work, we did not neglect the practical aspects of these systems. These were not rarified results and commercially impractical but lent themselves to eventual commercial products in the marketplace. The end result - a high performance replacement lamp - will save significant energy while providing a high-quality light source.

  13. Automated identification of terminal area air traffic flows and weather related deviations

    E-Print Network [OSTI]

    Ng, Tony M. Eng. Massachusetts Institute of Technology

    2008-01-01T23:59:59.000Z

    Air traffic in terminal air space is very complex, making it very difficult to identify air traffic flows. Finding air traffic flows and flow boundaries are very helpful in analyzing how air traffic would react to weather. ...

  14. An LED-based Flasher System for VERITAS

    E-Print Network [OSTI]

    Hanna, D; McCutcheon, M; Nikkinen, L; 10.1016/j.nima.2009.10.107

    2009-01-01T23:59:59.000Z

    We describe a flasher system designed for use in monitoring the gains of the photomultiplier tubes used in the VERITAS gamma-ray telescopes. This system uses blue light-emitting diodes (LEDs) so it can be operated at much higher rates than a traditional laser-based system. Calibration information can be obtained with better statistical precision with reduced loss of observing time. The LEDs are also much less expensive than a laser. The design features of the new system are presented, along with measurements made with a prototype mounted on one of the VERITAS telescopes.

  15. Global Rebalancing: US Protection versus Europe-led reflation

    E-Print Network [OSTI]

    Irvin, George; Izurieta, Alex

    2006-01-01T23:59:59.000Z

    impact of a Europe-led reflation is re-enforced by the strong income and trade linkages with middle- income and poor regions of the world (eg, Eastern Europe, Latin America and Africa)18. An EU-led reflation supposes a set of demand... switching on the required scale within an acceptable time frame. The central point is that the extra growth cannot come entirely or even chiefly from Asia (where resources are already stretched to the limit), but must come from a combination of renewed EU...

  16. LED Luminaire Lifetime: Recommendations For Testing and Reporting |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED Lighting

  17. LED Performance Specification Series: T8 Replacement Lamps

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED LightingOutdoor

  18. LED T8 Replacement Lamps | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED LightingOutdoorLEDT8

  19. LEDs Ready for Takeoff at Louisiana Airport | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED

  20. Laboratory to change vehicle traffic-screening regimen at vehicle...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Changes to vehicle traffic-screening Laboratory to change vehicle traffic-screening regimen at vehicle inspection station Lanes two through five will be open 24 hours a day and...

  1. automated control traffic: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    technology, are to increase the safety and through-put of the existing highway by traffic automation. Advanced Vehicle Control... Huandra, Rusli 1998-01-01 14 Traffic Control on...

  2. Supporting the Future Air Traffic Control Projection Process

    E-Print Network [OSTI]

    Davison, H. J.

    2003-01-01T23:59:59.000Z

    In air traffic control, projecting what the air traffic situation will be over the next 30 seconds to 30 minutes is a key process in identifying conflicts that may arise so that evasive action can be taken upon discovery ...

  3. Modeling and estimation techniques for understanding heterogeneous traffic behavior

    E-Print Network [OSTI]

    Zhao, Zhili

    2004-09-30T23:59:59.000Z

    The majority of current internet traffic is based on TCP. With the emergence of new applications, especially new multimedia applications, however, UDP-based traffic is expected to increase. Furthermore, multimedia applications have sparkled...

  4. A study of freeway traffic volume control

    E-Print Network [OSTI]

    Smith, Edwin McMurray

    1958-01-01T23:59:59.000Z

    LI8 RARY i & m ceLLCSE el' lEXAe A STUDY GP FRE8NAY TRAFFIC VOLUME CONTROL Mwin McMurray Smith A Thesis Submitteh to the GracLuate School of the Agricultural ant Mechanical College of Texas in partial fulfillment of the requirements...; to Mr. W. H. Carsten, Director, Department of Traffic Control, City of Dallas; to Mr. W. E. Carmichael, District Engineer, Texas Highway Department; and to the Texas Transportation Institute for furnishing the data which were analyzed for this thesis...

  5. Making the Traffic Operations Case for Congestion Pricing: Operational Impacts of Congestion Pricing

    SciTech Connect (OSTI)

    Chin, Shih-Miao [ORNL; Hu, Patricia S [ORNL; Davidson, Diane [ORNL

    2011-02-01T23:59:59.000Z

    Congestion begins when an excess of vehicles on a segment of roadway at a given time, resulting in speeds that are significantly slower than normal or 'free flow' speeds. Congestion often means stop-and-go traffic. The transition occurs when vehicle density (the number of vehicles per mile in a lane) exceeds a critical level. Once traffic enters a state of congestion, recovery or time to return to a free-flow state is lengthy; and during the recovery process, delay continues to accumulate. The breakdown in speed and flow greatly impedes the efficient operation of the freeway system, resulting in economic, mobility, environmental and safety problems. Freeways are designed to function as access-controlled highways characterized by uninterrupted traffic flow so references to freeway performance relate primarily to the quality of traffic flow or traffic conditions as experienced by users of the freeway. The maximum flow or capacity of a freeway segment is reached while traffic is moving freely. As a result, freeways are most productive when they carry capacity flows at 60 mph, whereas lower speeds impose freeway delay, resulting in bottlenecks. Bottlenecks may be caused by physical disruptions, such as a reduced number of lanes, a change in grade, or an on-ramp with a short merge lane. This type of bottleneck occurs on a predictable or 'recurrent' basis at the same time of day and same day of week. Recurrent congestion totals 45% of congestion and is primarily from bottlenecks (40%) as well as inadequate signal timing (5%). Nonrecurring bottlenecks result from crashes, work zone disruptions, adverse weather conditions, and special events that create surges in demand and that account for over 55% of experienced congestion. Figure 1.1 shows that nonrecurring congestion is composed of traffic incidents (25%), severe weather (15%), work zones, (10%), and special events (5%). Between 1995 and 2005, the average percentage change in increased peak traveler delay, based on hours spent in traffic in a year, grew by 22% as the national average of hours spent in delay grew from 36 hours to 44 hours. Peak delay per traveler grew one-third in medium-size urban areas over the 10 year period. The traffic engineering community has developed an arsenal of integrated tools to mitigate the impacts of congestion on freeway throughput and performance, including pricing of capacity to manage demand for travel. Congestion pricing is a strategy which dynamically matches demand with available capacity. A congestion price is a user fee equal to the added cost imposed on other travelers as a result of the last traveler's entry into the highway network. The concept is based on the idea that motorists should pay for the additional congestion they create when entering a congested road. The concept calls for fees to vary according to the level of congestion with the price mechanism applied to make travelers more fully aware of the congestion externality they impose on other travelers and the system itself. The operational rationales for the institution of pricing strategies are to improve the efficiency of operations in a corridor and/or to better manage congestion. To this end, the objectives of this project were to: (1) Better understand and quantify the impacts of congestion pricing strategies on traffic operations through the study of actual projects, and (2) Better understand and quantify the impacts of congestion pricing strategies on traffic operations through the use of modeling and other analytical methods. Specifically, the project was to identify credible analytical procedures that FHWA can use to quantify the impacts of various congestion pricing strategies on traffic flow (throughput) and congestion.

  6. Shedding new light on LEDs | Argonne National Laboratory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    diodes, are the secret behind your iPhone screen, flatscreen TVs, Christmas lights and crosswalk signals. They can last longer and save more energy than traditional...

  7. INTRODUCTION Several proposals for future air traffic man-

    E-Print Network [OSTI]

    Parasuraman, Raja

    for Aeronautics [RTCA], 1995) and Distributed Air/Ground Traffic Management (DAG-TM; Na- tional Aeronautics

  8. An Brief Overview Of Using LEDs In Lab

    E-Print Network [OSTI]

    Baas, Bevan

    Diodes · A Light-Emitting Diode (LED) is a special type of diode that emits photons (light) when current ­ Forward biased Diode Operation 0 V 5 V Current ~0 high (too high)5 V 0 V I anode cathode #12;3 Light-Emitting

  9. Small Area Array-Based LED Luminaire Design

    SciTech Connect (OSTI)

    Thomas Yuan

    2008-01-09T23:59:59.000Z

    This report contains a summary of technical achievements during a three-year project to demonstrate high efficiency LED luminaire designs based on small area array-based gallium nitride diodes. Novel GaN-based LED array designs are described, specifically addressing the thermal, optical, electrical and mechanical requirements for the incorporation of such arrays into viable solid-state LED luminaires. This work resulted in the demonstration of an integrated luminaire prototype of 1000 lumens cool white light output with reflector shaped beams and efficacy of 89.4 lm/W at CCT of 6000oK and CRI of 73; and performance of 903 lumens warm white light output with reflector shaped beams and efficacy of 63.0 lm/W at CCT of 2800oK and CRI of 82. In addition, up to 1275 lumens cool white light output at 114.2 lm/W and 1156 lumens warm white light output at 76.5 lm/W were achieved if the reflector was not used. The success to integrate small area array-based LED designs and address thermal, optical, electrical and mechanical requirements was clearly achieved in these luminaire prototypes with outstanding performance and high efficiency.

  10. Ultratech Develops an Improved Lithography Tool for LED Wafer Manufacturing

    Broader source: Energy.gov [DOE]

    Ultratech modified an existing lithography tool used for semiconductor manufacturing to better meet the cost and performance targets of the high-brightness LED manufacturing industry. The goal was to make the equipment compatible with the wide range of substrate diameters and thicknesses prevalent in the industry while reducing the capital cost and the overall cost of ownership (COO).

  11. Biofuels in the ASEAN Low Emission Development Strategies (LEDS) Forum

    E-Print Network [OSTI]

    9/20/2012 1 Biofuels in the ASEAN Low Emission Development Strategies (LEDS) Forum Bangkok, Thailand 19-21 September 2012 Biofuel Policy Group Asian Institute of Technology Outline of the Presentation 1. Objectives of this Presentation 2. Background 3. Status of Biofuel Development in ASEAN 4

  12. Heterostructures for Increased Quantum Efficiency in Nitride LEDs

    SciTech Connect (OSTI)

    Davis, Robert

    2010-09-30T23:59:59.000Z

    Task 1. Development of an advanced LED simulator useful for the design of efficient nitride-based devices. Simulator will contain graphical interface software that can be used to specify the device structure, the material parameters, the operating conditions and the desired output results. I-4 Task 2. Theoretical and experimental investigations regarding the influence on the microstructure, defect concentration, mechanical stress and strain and IQE of controlled changes in the chemistry and process route of deposition of the buffer layer underlying the active region of nitride-based blue- and greenemitting LEDs. I-9 Task 3. Theoretical and experimental investigations regarding the influence on the physical properties including polarization and IQE of controlled changes in the geometry, chemistry, defect density, and microstructure of components in the active region of nitride-based blue- and green-emitting LEDs. II-37 Task 4. Theoretical and experimental investigations regarding the influence on IQE of novel heterostructure designs to funnel carriers into the active region for enhanced recombination efficiency and elimination of diffusion beyond this region. II-52 Task 5. Theoretical and experimental investigations regarding the influence of enhanced p-type doping on the chemical, electrical, and microstructural characteristics of the acceptor-doped layers, the hole injection levels at Ohmic contacts, the specific contact resistivity and the IQE of nitride-based blue- and green-emitting LEDs. Development and optical and electrical characterization of reflective Ohmic contacts to n- and p-type GaN films. I

  13. Accident Analysis and Prevention 36 (2004) 933946 Freeway safety as a function of traffic flow

    E-Print Network [OSTI]

    Detwiler, Russell

    2004-01-01T23:59:59.000Z

    Accident Analysis and Prevention 36 (2004) 933­946 Freeway safety as a function of traffic flow of strong relationships between traffic flow conditions and the likelihood of traffic accidents (crashes reserved. Keywords: Traffic safety; Accident rates; Traffic flow; Loop detectors; Speed; Traffic density

  14. 130 LPW 1000 Lm Warm White LED for Illumination

    SciTech Connect (OSTI)

    Soer, Wouter

    2012-06-14T23:59:59.000Z

    An illumination-grade warm-white LED, having correlated color temperature (CCT) between 2700 and 3500 K and capable of producing 1000 lm output at over 130 lm/W at room temperature, has been developed in this program. The high-power warm-white LED is an ideal source for use in indoor and outdoor lighting applications. Over the two year period, we have made the following accomplishments: • Developed a low-cost high-power white LED package and commercialized a series of products with CCT ranging from 2700 to 5700 K under the product name LUXEON M; • Demonstrated a record efficacy of 124.8 lm/W at a flux of 1023 lm, CCT of 3435 K and color rendering index (CRI) over 80 at room temperature in the productized package; • Demonstrated a record efficacy of 133.1 lm/W at a flux of 1015 lm, CCT of 3475 K and CRI over 80 at room temperature in an R&D package. The new high-power LED package is a die-on-ceramic surface mountable LED package. It has four 2 mm2 InGaN pump dice, flip-chip attached to a ceramic submount in a 2x2 array configuration. The submount design utilizes a design approach that combines a high-thermal- conductivity ceramic core for die attach and a low-cost and low-thermal-conductivity ceramic frame for mechanical support and as optical lens carrier. The LED package has a thermal resistance of less than 1.25 K/W. The white LED fabrication also adopts a new batch level (instead of die-by-die) phosphor deposition process with precision layer thickness and composition control, which provides not only tight color control, but also low cost. The efficacy performance goal was achieved through the progress in following key areas: (1) high-efficiency royal blue pump LED development through active region design and epitaxial growth quality improvement (funded by internal programs); (2) improvement in extraction efficiency from the LED package through improvement of InGaN-die-level and package-level optical extraction efficiency; and (3) improvement in phosphor system efficiency by improving the lumen equivalent (LE) and phosphor package efficiency (PPE) through improvement in phosphor-package interactions. The high-power warm-white LED product developed has been proven to have good reliability through extensive reliability tests. The new kilo-lumen package has been commercialized under the product name LUXEON M. As of the end of the program, the LUXEON M product has been released in the following CCT/CRI combinations: 3000K/70, 4000K/70, 5000K/70, 5700K/70, 2700K/80, 3000K/80 and 4000K/80. LM-80 tests for the products with CCTs of 4000 K and higher have reached 8500 hours, and per IESNA TM-21-11 have established an L70 lumen maintenance value of >51,000 hours at A drive current and up to 120 °C board temperature.

  15. Author's personal copy Gasoline prices and traffic safety in Mississippi

    E-Print Network [OSTI]

    Levinson, David M.

    Author's personal copy Gasoline prices and traffic safety in Mississippi Guangqing Chi a, , Arthur November 2010 Keywords: Gasoline prices Traffic crashes Traffic safety Age Gender Race Problem: Limited literature suggests that gasoline prices have substantial effects on reducing fatal crashes. However

  16. Air Traffic Control Using Virtual Stationary Automata Matthew D. Brown

    E-Print Network [OSTI]

    Lynch, Nancy

    Air Traffic Control Using Virtual Stationary Automata by Matthew D. Brown B.S., Massachusetts by . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Arthur C. Smith Chairman, Department Committee on Graduate Students #12;Air Traffic Control Using Virtual of Engineering Abstract As air travel has become an essential part of modern life, the air traffic control system

  17. Supporting Air Traffic Flow Management with Agents Shawn R. Wolfe

    E-Print Network [OSTI]

    Yorke-Smith, Neil

    Supporting Air Traffic Flow Management with Agents Shawn R. Wolfe Intelligent Systems Division NASA Ames Research Center Moffett Field, CA 94035-1000 Shawn.R.Wolfe@nasa.gov Abstract Air traffic flow an agent-based system to facilitate mutually beneficial air traffic management decisions, and identify

  18. Randomization in Traffic Information Sharing Systems Masaaki Tanizaki

    E-Print Network [OSTI]

    Wolfson, Ouri E.

    , we consider a traffic information sharing system based on Floating Car Data (FCD). FCD is oneRandomization in Traffic Information Sharing Systems Masaaki Tanizaki Intelligent Media Systems to the server. The traffic information sharing system broadcasts speed information updated by such transmission

  19. NetViewer: A Network Traffic Visualization and Analysis Tool

    E-Print Network [OSTI]

    Reddy, Narasimha

    . NetViewer can be employed to detect and identify network anomalies such as DoS/DDoS attacks, worms from both the commercial and free soft- ware communities. To study and classify traffic on the network most of the time. In such cases, attack traffic may not induce significant overshoot in traffic volume

  20. A Touch Panel using Silicone Rubber with embedded IR-LEDs Yuichiro Sakamoto,

    E-Print Network [OSTI]

    Tanaka, Jiro

    LED LED FTIR FTIR FTIR FTIR FTIR LED LED A Touch Panel using Silicone Rubber with embedded Shizuki and Jiro Tanaka In this paper, we present a novel touch panel using silicone rubber with embedded are difficult to detect for one made of acryl panel Moreover, it integrates IR-LEDs silicone rubber for multi

  1. Online Calibration for Dynamic Traffic Constantinos Antoniou

    E-Print Network [OSTI]

    Bertini, Robert L.

    On­line Calibration for Dynamic Traffic Assignment Constantinos Antoniou October 5, 2007 Seminar­line DTA framework Demand simulator Supply simulator State estimation and model calibration Network calibration approaches include subset of these models Seminar at Portland State University 3 #12;Constantinos

  2. Does Daylight Savings Time Affect Traffic Accidents?

    E-Print Network [OSTI]

    Deen, Sophia 1988-

    2012-04-20T23:59:59.000Z

    This paper studies the effect of changes in accident pattern due to Daylight Savings Time (DST). The extension of the DST in 2007 provides a natural experiment to determine whether the number of traffic accidents is affected by shifts in hours...

  3. Smart-card traffic system keeps Singapore

    E-Print Network [OSTI]

    Hunt, Julian

    Smart-card traffic system keeps Singapore in the fast lane Sir -- Recognizing the high economic tariffs from a smart card installed in a slot near the vehicle's windscreen. Infringement is registered. For expressways and approach routes leading to the city, a tiered pricing scheme operates during the peak period

  4. Variability in continuous traffic monitoring data

    SciTech Connect (OSTI)

    Wright, T.; Hu, P.S. [Oak Ridge National Lab., TN (United States); Young, J. [Tennessee Univ., Knoxville, TN (United States)

    1996-07-01T23:59:59.000Z

    Each state in the United States can be viewed as a universe of road segments. For each road segment in each state, it is desired to know various traffic characteristics based on count data, classification count data, and weigh-in-motion data. These data are absolutely essential for highway design, maintenance, safety, and planning. Given no cost constraints, each road segment would be continuously monitored every day of the year. However, in practice, a few road segments are monitored continuously every day of the year to produce annual characteristics of traffic flow. The remaining road segments are monitored for one or two days each year, and this resulting data are `adjusted` (using factors based on data collected from the continuously monitored road segments) to produce estimates of annual characteristics. With this general approach, each state strives to provide estimates of annual characteristics for each road segment within its jurisdiction. In 1985, the Federal Highway Administration (FHWA) published the Traffic Monitoring Guide to assist states in achieving this end. As with almost any data collection effort, the monitoring data suffers from errors from many sources. In this paper, we report some empirical findings in a research project sponsored by the FHWA. This research project studied the variability in the traffic data from the continuously monitored road segments from state(s) and, the extent to which this variability is transferred to and affects the precision of the data produced from the road segments which are monitored only one or two days each year. The ultimate hope is that states will eventually be able to not only publish an estimate of a characteristic such as Average Annual Daily Traffic (AADT) for each road segment, but also that each estimate will be accompanied by a statement expressing how good the estimate is in terms of its estimated variability or precision, which will likely be expressed as a coefficient of variation.

  5. LED Retrofit Project in TSH Basement On July 14 2014, McMaster Facilities Services completed an energy conservation lighting

    E-Print Network [OSTI]

    Haykin, Simon

    replaced with the new LED (light emitting diode) tubes. LEDs have better lighting quality, lower energy

  6. OSRAM SYLVANIA Develops High-Efficiency LED Troffer Replacement

    Broader source: Energy.gov [DOE]

    With the help of DOE funding, OSRAM SYLVANIA is developing a high-efficiency LED 2'x2' troffer replacement that is expected to be commercially available in the spring of 2012 and to be cost-competitive with existing troffers of that size. It is projected to have a light output of up to 4,000 lumens, an efficacy of more than 100 lm/W, and a CCT of 3500K.

  7. KLA-Tencor's Inspection Tool Reduces LED Manufacturing Costs

    Broader source: Energy.gov [DOE]

    With the help of DOE funding, KLA-Tencor is developing an improved inspection tool for LED manufacturing that promises to significantly increase overall process yields and minimize expensive waste. The power of the inspection tool lies in optical detection techniques coupled with defect source analysis software to statistically correlate front-end geometric anomalies in the substrate to killer defects on the back end of the manufacturing line, which give rise to an undesirable or unusable end product.

  8. Retail Lamps Study 3.1: Dimming, Flicker, and Power Quality Characteristics of LED A Lamps.

    SciTech Connect (OSTI)

    Royer, Michael P.; Poplawski, Michael E.; Brown, Charles C.

    2014-12-14T23:59:59.000Z

    To date, all three reports in the retail lamps series have focused on basic performance parameters, such as lumen output, efficacy, and color quality. This report goes a step further, examining the photoelectric characteristics (i.e., dimming and flicker) of a subset of lamps from CALiPER Retails Lamps Study 3. Specifically, this report focuses on the dimming, power quality, and flicker characteristics of 14 LED A lamps, as controlled by four different retail-available dimmers. The results demonstrate notable variation across the various lamps, but little variation between the four dimmers. Overall, the LED lamps: ~tended to have higher relative light output compared to the incandescent and halogen benchmark at the same dimmer output signal (RMS voltage). The lamps’ dimming curves (i.e., the relationship between control signal and relative light output) ranged from linear to very similar to the square-law curve typical of an incandescent lamp. ~generally exhibited symmetrical behavior—the same dimming curve—when measured proceeding from maximum to minimum or minimum to maximum control signal. ~mostly dimmed below 10% of full light output, with some exceptions for specific lamp and dimmer combinations ~exhibited a range of flicker characteristics, with many comparing favorably to the level typical of a magnetically-ballasted fluorescent lamp through at least a majority of the dimming range. ~ always exceeded the relative (normalized) efficacy over the dimming range of the benchmark lamps, which rapidly decline in efficacy when they are dimmed. This report generally does not attempt to rank the performance of one product compared to another, but instead focuses on the collective performance of the group versus conventional incandescent or halogen lamps, the performance of which is likely to be the baseline for a majority of consumers. Undoubtedly, some LED lamps perform better—or more similar to conventional lamps—than others. Some perform desirably for one characteristic, but not others. Consumers (and specifiers) may have a hard time distinguishing better-performing lamps from one another; at this time, physical experimentation is likely the best evaluation tool.

  9. Observed Minimum Illuminance Threshold for Night Market Vendors in Kenya who use LED Lamps

    E-Print Network [OSTI]

    Johnstone, Peter

    2009-01-01T23:59:59.000Z

    data logger equipped rechargeable LED lamps, monitoring theadoption of the LED lamps, and a follow-up survey.s kiosk illuminated by an LED lamp Radecsky, K. , P.

  10. Assessing the Performance of 5mm White LED Light Sources for Developing-Country Applications

    E-Print Network [OSTI]

    Mills, Evan

    2007-01-01T23:59:59.000Z

    lamp calibrated by Labsphere Spectral measurements - LEDs inLEDs we tested is exceptionally good (as good or better than many compact fluorescent lamps),lamp. Off-grid lighting products using the poorer LEDs would

  11. Application Summary Report 22: LED MR16 Lamps

    SciTech Connect (OSTI)

    Royer, Michael P.

    2014-07-23T23:59:59.000Z

    This report analyzes the independently tested photometric performance of 27 LED MR16 lamps. It describes initial performance based on light output, efficacy, distribution, color quality, electrical characteristics, and form factor, with comparisons to a selection of benchmark halogen MR16s and ENERGY STAR qualification thresholds. Three types of products were targeted. First, CALiPER sought 3000 K lamps with the highest rated lumen output (i.e., at least 500 lm) or a claim of equivalency to a 50 W halogen MR16 or higher. The test results indicate that while the initial performance of LED MR16s has improved across the board, market-available products still do not produce the lumen output and center beam intensity of typical 50 W halogen MR16 lamps. In fact, most of the 18 lamps in this category had lower lumen output and center beam intensity than a typical 35 W halogen MR16 lamp. Second, CALiPER sought lamps with a CRI of 90 or greater. Only four manufacturers were identified with a product in this category. CALiPER testing confirmed the performance of these lamps, which are a good option for applications where high color fidelity is needed. A vast majority of the LED MR16 lamps have a CRI in the low 80s; this is generally acceptable for ambient lighting, but may not always be acceptable for focal lighting. For typical LED packages, there is a fundamental tradeoff between CRI and efficacy, but the lamps in the high-CRI group in this report still offer comparable performance to the rest of the Series 22 products in other performance areas. Finally, CALiPER sought lamps with a narrow distribution, denoted as a beam angle less than 15°. Five such lamps were purchased. Notably, no lamp was identified as having high lumen output (500 lumens or greater), high CRI (90 or greater), a narrow distribution (15° or less), and an efficacy greater than 60 lm/W. This would be an important achievement for LED MR16s especially if output could reach approximately 700 800 lumens, or the approximate equivalent of a 50 W halogen MR16 lamp. Many factors beyond photometric performance should be considered during specification. For example, performance over time, transformer and dimmer compatibility, and total system performance are all critical to a successful installation. Subsequent CALiPER reports will investigate more complex issues.

  12. LED Site Lighting in the Commercial Building Sector: Opportunities, Challenges, and the CBEA Performance Specification

    Broader source: Energy.gov [DOE]

    This March 26, 2009 webcast presented information about the Commercial Building Energy Alliances' (CBEA) efforts to explore the viability of LED site lighting in commercial parking lots. LED...

  13. Metropolitan Road Traffic Simulation on FPGAs.

    SciTech Connect (OSTI)

    Tripp J. L. (Justin L.); Mortveit, H. S. (Henning S.); Hansson, A. A. (Anders A.); Gokhale, M. (Maya)

    2005-01-01T23:59:59.000Z

    This work demonstrates that road traffic simulation of entire metropolitan areas is possible with reconfigurable supercomputing that combines 64-bit microprocessors and FPGAs in a high bandwidth, low latency interconnect. Previously, traffic simulation on FPGAs was limited to very short road segments or required a very large number of FPGAs. Our data streaming approach overcomes scaling issues associated with direct implementations and still allows for high-level parallelism by dividing the data sets between hardware and software across the reconfigurable supercomputer. Using one FPGA on the Cray XD1 supercomputer, we are able to achieve a 34.4 x speed up over the AMD microprocessor. System integration issues must be optimized to exploit this speedup in the overall simulation.

  14. High Efficacy Green LEDs by Polarization Controlled MOVPE

    SciTech Connect (OSTI)

    Wetzel, Christian

    2013-03-31T23:59:59.000Z

    Amazing performance in GaInN/GaN based LEDs has become possible by advanced epitaxial growth on a wide variety of substrates over the last decade. An immediate push towards product development and worldwide competition for market share have effectively reduced production cost and generated substantial primary energy savings on a worldwide scale. At all times of the development, this economic pressure forced very fundamental decisions that would shape huge industrial investment. One of those major aspects is the choice of epitaxial growth substrate. The natural questions are to what extend a decision for a certain substrate will limit the ultimate performance and to what extent, the choice of a currently more expensive substrate such as native GaN could overcome any of the remaining performance limitations. Therefore, this project has set out to explore what performance characteristic could be achieved under the utilization of bulk GaN substrate. Our work was guided by the hypotheses that line defects such as threading dislocations in the active region should be avoided and the huge piezoelectric polarization needs to be attenuated – if not turned off – for higher performing LEDs, particularly in the longer wavelength green and deep green portions of the visible spectrum. At their relatively lower performance level, deep green LEDs are a stronger indicator of relative performance improvements and seem particular sensitive to the challenges at hand. The project therefore made use of recently developed non-polar and semipolar bulk GaN substrates that were made available at Kyma Technologies by crystallographic cuts from thick polar growth of GaN. This approach naturally leads to rather small pieces of substrates, cm along the long side while mm along the short one. Small size and limited volume of sample material therefore set the limits of the ensuing development work. During the course of the project we achieved green and deep green LEDs in all those crystal growth orientations: polar c-plane, non- polar a-plane, non-polar m-plane, and semipolar planes. The active region in those structures shows dramatically reduced densities of threading dislocations unless the wavelength was extended as far as 510 nm and beyond. With the appearance of such defects, the light output power dropped precipitously supporting the necessity to avoid any and all of such defects to reach the active region. Further aspects of the non-polar growth orientation proved extremely promising for the development of such structures. Chief among them is our success to achieve extremely uniform quantum wells in these various crystal orientations that prove devoid of any alloy fluctuation beyond the theoretical limit of a binominal distribution. This became very Rensselaer Wetzel DE?EE0000627 3 directly apparent in highly advanced atom probe tomography performed in collaboration at Northwestern University. Furthermore, under reduced or absence of piezoelectric polarization, green emitters in those growth geometries exhibit an unsurpassed wavelength stability over very wide excitation and drive current ranges. Such a performance had not been possible in any polar c-plane growth and now places green LEDs in terms of wavelength stability up par with typical 450 nm blue emitters. The project also incorporated enabling opportunities in the development of micro and nano- patterned substrate technologies. Originally developped as a means to enhance generated light extraction we have demonstrated that the method of nano-patterning, in contrast to micro- patterning also results in a substantial reduction of threading dislocation generation. In green LEDs, we thereby see equal contributions of enhanced light extraction and reduced defect generation to a threefold enhancement of the green light output power. These results have opened entirely new approaches for future rapid and low cost epitaxial material development by avoidance of thick defect accommodation layers. All methods developed within this project have meanwhile widely been publicized by the members o

  15. FPGA Based Real-time Network Traffic Analysis using Traffic Dispersion Patterns

    SciTech Connect (OSTI)

    Khan, F; Gokhale, M; Chuah, C N

    2010-03-26T23:59:59.000Z

    The problem of Network Traffic Classification (NTC) has attracted significant amount of interest in the research community, offering a wide range of solutions at various levels. The core challenge is in addressing high amounts of traffic diversity found in today's networks. The problem becomes more challenging if a quick detection is required as in the case of identifying malicious network behavior or new applications like peer-to-peer traffic that have potential to quickly throttle the network bandwidth or cause significant damage. Recently, Traffic Dispersion Graphs (TDGs) have been introduced as a viable candidate for NTC. The TDGs work by forming a network wide communication graphs that embed characteristic patterns of underlying network applications. However, these patterns need to be quickly evaluated for mounting real-time response against them. This paper addresses these concerns and presents a novel solution for real-time analysis of Traffic Dispersion Metrics (TDMs) in the TDGs. We evaluate the dispersion metrics of interest and present a dedicated solution on an FPGA for their analysis. We also present analytical measures and empirically evaluate operating effectiveness of our design. The mapped design on Virtex-5 device can process 7.4 million packets/second for a TDG comprising of 10k flows at very high accuracies of over 96%.

  16. Chaos control in traffic flow models

    E-Print Network [OSTI]

    Elman Mohammed Shahverdiev; Shin-ichi Tadaki

    1998-11-30T23:59:59.000Z

    Chaos control in some of the one- and two-dimensional traffic flow dynamical models in the mean field theory is studied.One dimensional model is investigated taking into account the effect of random delay. Two dimensional model takes into account the effects of overpasses, symmetric distribution of cars and blockages of cars moving in the same direction. Chaos synchronization is performed within both replica and nonreplica approaches, and using parameter perturbation method.

  17. Bicycle traffic planning and design criteria

    E-Print Network [OSTI]

    Vathana, Jhirasak

    1975-01-01T23:59:59.000Z

    for bicycle facilities, 34 15 16 17 18 19 20 21 Bicycle and wheelchair ramp, Curb drain opening spacings Bicycle facility extruded curb Curb drain opening spacing. Bicycle facility signing. Motor vehicle directed warning signs' Regulatory signs... design: Bicycle facility on 59 an arterial street crossing a collector street. The bicycle facility is separated from motor vehicle traffic by strip, 32 German intersection design: bicycle facility on 60 an arterial street crossing a collector street...

  18. Feedback-Controlled LED Photobioreactor for Photophysiological Studies of Cyanobacteria

    SciTech Connect (OSTI)

    Melnicki, Matthew R.; Pinchuk, Grigoriy E.; Hill, Eric A.; Kucek, Leo A.; Stolyar, Sergey; Fredrickson, Jim K.; Konopka, Allan; Beliaev, Alex S.

    2013-04-09T23:59:59.000Z

    A custom photobioreactor (PBR) was designed to enable automatic light adjustments using computerized feedback control. A black anodized aluminum enclosure, constructed to surround the borosilicate reactor vessel, prevents the transmission of ambient light and serves as a mount for arrays of light-emitting diodes (LEDs). The high-output LEDs provide narrow-band light of either 630 or 680 nm for preferential excitation of the cyanobacterial light-harvesting pigments, phycobilin or chlorophyll a, respectively. Custom developed software BioLume provides automatic control of optical properties and a computer feedback loop can automatically adjust the incident irradiance as necessary to maintain a fixed transmitted light through the culture, based on user-determined set points. This feedback control serves to compensate for culture dynamics which have optical effects, (e.g., changing cell density, pigment adaptations) and thus can determine the appropriate light conditions for physiological comparisons or to cultivate light-sensitive strains, without prior analyses. The LED PBR may also be controlled as a turbidostat, using a feedback loop to continuously adjust the rate of media-dilution based on the transmitted light measurements, with a fast and precise response. This cultivation system gains further merit as a high-performance analytical device, using non-invasive tools (e.g., dissolved gas sensors, online mass spectrometry) to automate real-time measurements, thus permitting unsupervised experiments to search for optimal growth conditions, to monitor physiological responses to perturbations, as well as to quantitate photophysiological parameters using an in situ light-saturation response routine.

  19. Traffic flow wide-area surveillance system definition

    SciTech Connect (OSTI)

    Allgood, G.O.; Ferrell, R.K.; Kercel, S.W.; Abston, R.A.; Carnal, C.L. [Oak Ridge National Lab., TN (United States); Moynihan, P.I. [Jet Propulsion Lab., Pasadena, CA (United States)

    1994-11-01T23:59:59.000Z

    Traffic Flow Wide-Area Surveillance (TFWAS) is a system for assessing the state of traffic flow over a wide area for enhanced traffic control and improved traffic management and planning. The primary purpose of a TFWAS system is to provide a detailed traffic flow description and context description to sophisticated traffic management and control systems being developed or envisioned for the future. A successful TFWAS system must possess the attributes of safety, reconfigurability, reliability, and expandability. The primary safety premise of TFWAS is to ensure that no action or failure of the TFWAS system or its components can result in risk of injury to humans. A wide variety of communication techniques is available for use with TFWAS systems. These communication techniques can be broken down into two categories, landlines and wireless. Currently used and possible future traffic sensing technologies have been examined. Important criteria for selecting TFWAS sensors include sensor capabilities, costs, operational constraints, sensor compatibility with the infrastructure, and extent. TFWAS is a concept that can take advantage of the strengths of different traffic sensing technologies, can readily adapt to newly developed technologies, and can grow with the development of new traffic control strategies. By developing innovative algorithms that will take information from a variety of sensor types and develop descriptions of traffic flows over a wide area, a more comprehensive understanding of the traffic state can be provided to the control system to perform the most reasonable control actions over the entire wide area. The capability of characterizing the state of traffic over an entire region should revolutionize developments in traffic control strategies.

  20. Synthesis and luminescence properties of rare earth activated phosphors for near UV-emitting LEDs for efficacious generation of white light

    E-Print Network [OSTI]

    Han, Jinkyu

    2013-01-01T23:59:59.000Z

    high-color-rendering LED lamps using oxyfluoride andin white LED. (a) Typical LED lamp package. (b) Uniformin white LED. (a) Typical LED lamp package. (b) Uniform

  1. Considerations When Comparing LED and Conventional Lighting | Department of

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 1112011AT&T, Inc.'sEnergyTexas1.SpaceFluor Federal Services -Energy Using LEDs »

  2. LED Holiday Lights: Festive, Safe, and Efficient! | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM to 2:05PMDOE-STD-1107-97LSEED:LDVFrequentlyLED

  3. LEDs: The Future of Lighting is Here | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LEDLEDs on Semipolar

  4. LED Lighting on the National Mall | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreaking ofOil & Gas » MethaneJohnsonKristina Pflanz About Us KristinaLED

  5. #AskEnergySaver: LED Lights | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't Your Destiny: The Future of Bad CholesteroliManage#AskEnergySaver: LED Lights #AskEnergySaver:

  6. Reducing LED Costs Through Innovation | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page onYouTube YouTube Note: Since the.pdfBreakingMay 2015 < prevQuick Guide:U.N.June 8,PastRadiationReducing LED Costs

  7. Slutrapport for PSO 337-068 Udvikling af LED lyskilder og lamper

    E-Print Network [OSTI]

    bulb. - two LED pendants/lamps, a LED table lamp and a chair with LED lighting developed by designers Cluster lampe 13 Teknisk design af Cluster 15 Konklusion 16 Lysflyder 17 Hvordan opstod ideen om en LEDSlutrapport for PSO 337-068 Udvikling af LED lyskilder og lamper Carsten Dam-Hansen, Paul Michael

  8. Streamlining Transportation Corridor Planning Processess: Freight and Traffic Information

    SciTech Connect (OSTI)

    Franzese, Oscar [ORNL

    2010-08-01T23:59:59.000Z

    The traffic investigation is one of the most important parts of an Environmental Impact Statement of projects involving the construction of new roadway facilities and/or the improvement of existing ones. The focus of the traffic analysis is on the determination of anticipated traffic flow characteristics of the proposed project, by the application of analytical methods that can be grouped under the umbrella of capacity analysis methodologies. In general, the main traffic parameter used in EISs to describe the quality of traffic flow is the Level of Service (LOS). The current state of the practice in terms of the traffic investigations for EISs has two main shortcomings. The first one is related to the information that is necessary to conduct the traffic analysis, and specifically to the lack of integration among the different transportation models and the sources of information that, in general, reside in GIS databases. A discussion of the benefits of integrating CRS&SI technologies and the transportation models used in the EIS traffic investigation is included. The second shortcoming is in the presentation of the results, both in terms of the appearance and formatting, as well as content. The presentation of traffic results (current and proposed) is discussed. This chapter also addresses the need of additional data, in terms of content and coverage. Regarding the former, other traffic parameters (e.g., delays) that are more meaningful to non-transportation experts than LOS, as well as additional information (e.g., freight flows) that can impact traffic conditions and safety are discussed. Spatial information technologies can decrease the negative effects of, and even eliminate, these shortcomings by making the relevant information that is input to the models more complete and readily available, and by providing the means to communicate the results in a more clear and efficient manner. The benefits that the application and use of CRS&SI technologies can provide to improve and expedite the traffic investigation part of the EIS process are presented.

  9. Traffic congestion forecasting model for the INFORM System. Final report

    SciTech Connect (OSTI)

    Azarm, A.; Mughabghab, S.; Stock, D.

    1995-05-01T23:59:59.000Z

    This report describes a computerized traffic forecasting model, developed by Brookhaven National Laboratory (BNL) for a portion of the Long Island INFORM Traffic Corridor. The model has gone through a testing phase, and currently is able to make accurate traffic predictions up to one hour forward in time. The model will eventually take on-line traffic data from the INFORM system roadway sensors and make projections as to future traffic patterns, thus allowing operators at the New York State Department of Transportation (D.O.T.) INFORM Traffic Management Center to more optimally manage traffic. It can also form the basis of a travel information system. The BNL computer model developed for this project is called ATOP for Advanced Traffic Occupancy Prediction. The various modules of the ATOP computer code are currently written in Fortran and run on PC computers (pentium machine) faster than real time for the section of the INFORM corridor under study. The following summarizes the various routines currently contained in the ATOP code: Statistical forecasting of traffic flow and occupancy using historical data for similar days and time (long term knowledge), and the recent information from the past hour (short term knowledge). Estimation of the empirical relationships between traffic flow and occupancy using long and short term information. Mechanistic interpolation using macroscopic traffic models and based on the traffic flow and occupancy forecasted (item-1), and the empirical relationships (item-2) for the specific highway configuration at the time of simulation (construction, lane closure, etc.). Statistical routine for detection and classification of anomalies and their impact on the highway capacity which are fed back to previous items.

  10. Optimization Online - Test instances for the traffic assignment problem

    E-Print Network [OSTI]

    Frédéric Babonneau

    Abstract: This short note on the Traffic Assignment Problem (TAP) provides the relevant information on test problems previously used in the literature to facilitate

  11. average daily traffic: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Next Page Last Page Topic Index 1 April 2014 Annual Average DailyTraffic (AADT) is a key input in operations and transportation planning Environmental Sciences and Ecology...

  12. Measurements of Diesel Truck Traffic Associated with Goods Movement

    E-Print Network [OSTI]

    Houston, Douglas; Krudysz, Margaret; Winer, Arthur

    2007-01-01T23:59:59.000Z

    Concentrations of PM2.5 and Diesel Exhaust Particles onPatterns of Measured Port Diesel Traffic. (a) Intersectionof particulate emissions from diesel engines: a review’, J.

  13. adaptive traffic flow: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    C; Sahni, Onkar; Shephard, Mark S; Jansen, Kenneth E 2014-01-01 143 The inhomogeneous kinematic wave traffic flow model as a resonant nonlinear system Engineering Websites...

  14. Circulating fibrocytes traffic to the lungs in response to CXCL12 and mediate fibrosis

    E-Print Network [OSTI]

    2004-01-01T23:59:59.000Z

    fibrocytes traffic to the lungs in response to CXCL12 andto CXCL12 and traffics to the lungs in a murine model of+ fibrocytes also traffic to the lungs in response to a

  15. Road traffic accidents in Kathmandużan hour of education yields a glimmer of hope

    E-Print Network [OSTI]

    Basnet, Bibhusan; Vohra, Rais; Bhandari, Amit; Pandey, Subash

    2013-01-01T23:59:59.000Z

    et al. : Road traffic accidents in Kathmandu— an hour ofOpen Access Road traffic accidents in Kathmandu—an hour ofnumber of road traffic accidents in the year 2012 decreased

  16. Post processing large integer programming problems in air traffic flow management

    E-Print Network [OSTI]

    Gangadharan, Rajesh

    1994-01-01T23:59:59.000Z

    The Federal Aviation Administration is keen to develop new strategies for air traffic control, in order to better tackle the numerous problems arising due to increasing traffic in the national air space. The Traffic Flow Management (TFM) problem...

  17. Cyclist route choice, traffic-related air pollution, and lung function: a scripted exposure study

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    choice, traffic-related air pollution, and lung function: aexposure to traffic-related air pollution on respiratory andR: Traffic- related air pollution and acute changes in heart

  18. Multimedia Traffic Routing in Multilayer WDM Networks

    E-Print Network [OSTI]

    Amphawan, Angela; Hasan, Hassanuddin

    2012-01-01T23:59:59.000Z

    The advent of real-time multimedia services over the Internet has stimulated new technologies for expanding the information carrying capacity of optical network backbones. Multilayer wavelength division multiplexing (WDM) packet switching is an emerging technology for increasing the bandwidth of optical networks. Two algorithms for the routing of the multimedia traffic flows were applied: (i) Capacitated Shortest Path First (CSPF) routing, which minimizes the distance of each flow linking the given source and destination nodes and satisfying capacity constraints; and (ii) Flow Deviation Algorithm (FDA) routing, which minimizes the network?wide average packet delay.

  19. Traffic lights for crop-based biofuels

    E-Print Network [OSTI]

    Phalan, Ben

    Traffic lights for crop-based biofuels Ben Phalan Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK Email: btp22@cam.ac.uk Nobody likes to have limits put on their freedom. However, in all areas of life... of having to slow down is an acceptable price to pay if it reduces the number of pedestrians killed and injured. How is this relevant to biofuels? There are many different kinds of biofuels, including some with considerable potential to generate cleaner...

  20. Hanford Traffic Safety FAQs - Hanford Site

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cn SunnybankD.jpgHanford LEED&soil Hanford Traffic Department

  1. NAC 484 - Traffic Laws | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal Pwer PlantMunhall, Pennsylvania: Energy Resources Jump to:MuskingumMyers-4 Jump-84 - Traffic Laws

  2. A mathematical model and descent algorithm for bilevel traffic management

    E-Print Network [OSTI]

    Patriksson, Michael

    variables enter as parameters in the travel costs. We consider a (small) variety of model settings, and interpret their workings in terms of the traffic network. Key words: Traffic equilibrium; Stackelberg game derivative; Armijo line search; stationary point. 1 Introduction The need for measures to reduce congestion

  3. AN UNSCENTED KALMAN FILTER FOR FREEWAY TRAFFIC ESTIMATION

    E-Print Network [OSTI]

    Mihaylova, Lyudmila

    AN UNSCENTED KALMAN FILTER FOR FREEWAY TRAFFIC ESTIMATION L. Mihaylova , R. Boel and A. Hegyi at boundaries between some segments and averaged within regular time intervals. An Unscented Kalman filter state. Keywords: macroscopic traffic models, unscented Kalman filter, particle filter 1. INTRODUCTION

  4. Model Reference Adaptive Control Framework for Real Time Traffic

    E-Print Network [OSTI]

    Minnesota, University of

    Adaptive Control #12;12 Prescriptive Dynamic Traffic Assignment A Prediction Model and the Reference ModelModel Reference Adaptive Control Framework for Real Time Traffic Management Under Emergency Movement Volume Adaptive Controller Model Reference Adaptive Control (MRAC) Assumptions Super Zone Concept

  5. Hybrid Control Models of Next Generation Air Traffic Management ?

    E-Print Network [OSTI]

    Pappas, George J.

    Hybrid Control Models of Next Generation Air Traffic Management ? C. Tomlin, G. Pappas, J. Lygeros of California at Berkeley Berkeley, CA 94720 Abstract. The study of hierarchical, hybrid control systems by today's Air Traffic Control (ATC), a ground­based system which routes aircraft along predefined jet ways

  6. Joint Traffic Blocking and Routing under Network Failures and Maintenances

    E-Print Network [OSTI]

    Liu, Yong

    Joint Traffic Blocking and Routing under Network Failures and Maintenances Chao Liang ECE Dept paths. Therefore, it is important to design ingress traffic blocking and routing jointly to achieve a good balance between the two factors. Working towards this goal, we formulate a joint ingress blocking

  7. Jetway: Minimizing Costs on Inter-Datacenter Video Traffic

    E-Print Network [OSTI]

    Li, Baochun

    Jetway: Minimizing Costs on Inter-Datacenter Video Traffic Yuan Feng, Baochun Li Department deploy a number of datacenters inter-connected by high-capacity links, spanning different geographical by ISPs, such inter-datacenter video traffic incurs substantial operational costs to a cloud provider

  8. Top-percentile traffic routing problem by Dynamic Programming

    E-Print Network [OSTI]

    Grothey, Andreas

    Top-percentile traffic routing problem by Dynamic Programming Andreas Grothey, Xinan Yang School according to top-percentile pricing. We call this problem the Top-percentile Traffic Routing Problem (Tp problem, which is hard to solve due to the integer variables introduced by top-percentile pricing. Several

  9. Statistical traffic classification by Boosting Support Vector Machines

    E-Print Network [OSTI]

    Statistical traffic classification by Boosting Support Vector Machines Gabriel Gómez Sena Facultad years, traffic classification based on the statistical properties of flows has become an important topic. In this paper we statistically analyze the data length of the first few segments exchanged by a transport flow

  10. Geometric Programming and Mechanism Design for Air Traffic Conflict Resolution

    E-Print Network [OSTI]

    Pappas, George J.

    methods in air traffic control. The problem considered concerns the scheduling of the crossing times traffic controller (ATC). In this setting, numerous conflict resolution methods have been proposed have different valuations for the additional delays imposed by the ATC, and might be willing

  11. Increasing Air Traffic: What is the Problem? Areski Hadjaz

    E-Print Network [OSTI]

    Boyer, Edmond

    Increasing Air Traffic: What is the Problem? Areski Hadjaz Thales Air Systems, Rungis, France Email: areski.hadjaz@thalesgroup.com Ga´etan Marceau Thales Air Systems and TAO, Rungis, France Email: gaetan efforts are made to modernize the air traffic management systems to cope with uncertainty, complexity

  12. Traffic Analysis: From Stateful Firewall to Network Intrusion Detection System

    E-Print Network [OSTI]

    Chiueh, Tzi-cker

    1 Traffic Analysis: From Stateful Firewall to Network Intrusion Detection System Fanglu Guo Tzi normalization. Index Terms Packet (traffic) analysis, stateful firewall, network intrusion detection system intrusion detection system (NIDS). Stateful firewall analyzes packets up to their layer 4 headers while NIDS

  13. Guest Editorial Traffic classification and its applications to modern networks

    E-Print Network [OSTI]

    Mellia, Marco

    , such as the enforcement of quality of service guarantees or traffic engineering, and of security issues such as intrusion use of encryption techniques, make the measurement, analysis and classifica- tion of Internet traffic are being published here: ``Targeting Spam Control on Middleboxes: Spam Detection Based on Layer-3 E- mail

  14. Predictability of road traffic and congestion in urban areas

    E-Print Network [OSTI]

    Wang, Jingyuan; Li, Jing; Li, Chao; Xiong, Zhang; Wang, Wen-Xu

    2014-01-01T23:59:59.000Z

    Mitigating traffic congestion on urban roads, with paramount importance in urban development and reduction of energy consumption and air pollution, depends on our ability to foresee road usage and traffic conditions pertaining to the collective behavior of drivers, raising a significant question: to what degree is road traffic predictable in urban areas? Here we rely on the precise records of daily vehicle mobility based on GPS positioning device installed in taxis to uncover the potential daily predictability of urban traffic patterns. Using the mapping from the degree of congestion on roads into a time series of symbols and measuring its entropy, we find a relatively high daily predictability of traffic conditions despite the absence of any a priori knowledge of drivers' origins and destinations and quite different travel patterns between weekdays and weekends. Moreover, we find a counterintuitive dependence of the predictability on travel speed: the road segment associated with intermediate average travel ...

  15. Demonstration Assessment of Light Emitting Diode (LED) Commercial Garage Lights In the Providence Portland Medical Center, Portland, Oregon

    SciTech Connect (OSTI)

    Ton, My K.; Richman, Eric E.; Gilbride, Theresa L.

    2008-11-11T23:59:59.000Z

    This U.S. Department of Energy GATEWAY Demonstration project studied the applicability of light-emitting diode (LED) luminaires for commercial parking garage applications. High-pressure sodium (HPS) area luminaires were replaced with new LED area luminaires. The project was supported under the U.S. Department of Energy (DOE) Solid State Lighting Program. Other participants in the demonstration project included Providence Portland Medical Center in Portland, Oregon, the Energy Trust of Oregon, and Lighting Sciences Group (LSG) Inc. Pacific Northwest National Laboratory (PNNL) conducted the measurements and analysis of the results. PNNL manages GATEWAY demonstrations for DOE and represents their perspective in the conduct of the work. Quantitative and qualitative measurements of light and electrical power were taken at the site for both HPS and LED light sources. Economic costs were estimated and garage users’ responses to the new light sources were gauged with a survey. Six LED luminaires were installed in the below-ground parking level A, replacing six existing 150W HPS lamps spread out over two rows of parking spaces. Illuminance measurements were taken at floor level approximately every 4 ft on a 60-ft x 40-ft grid to measure light output of these LED luminaires which were termed the “Version 1” luminaires. PNNL conducted power measurements of the circuit in the garage to which the 6 luminaires were connected and determined that they drew an average of 82 W per lamp. An improved LED luminaire, Version 2, was installed in Level B of the parking garage. Illuminance measurements were not made of this second luminaire on site due to higher traffic conditions, but photometric measurements of this lamp and Version 1 were made in an independent testing laboratory and power usage for Version 2 was also measured. Version 1 was found to produce 3600 lumens and Version 2 was found to produce 4700 lumens of light and to consume 78 Watts. Maximum and minimum light levels were measured for the HPS and LED Version 1 luminaires and projected for the Version 2 luminaires. Maximum light levels were 23.51 foot candles, 20.54 fc, and 26.7 fc respectively and minimum light levels were 1.49 fc, 1.45 fc, and 1.88 fc. These results indicate very similar or even slightly higher light levels produced by the LED lamps, despite the higher lumen output of the HPS lamp. The LED lamps provide higher luminaire efficacy because all of the light is directed down and out. None of it is “lost” in the fixture. Also the HPS luminaire had poorly designed optics and a plastic covering that tended to get dirty and cracked, further decreasing the realized light output.[is this an accurate way to say this?] Consumer perceptions of the Version 2 LED were collected via a written survey form given to maintenance and security personnel. More than half felt the LED luminaires provided more light than the HPS lamps and a majority expressed a preference for the new lamps when viewing the relamped area through a security camera. Respondents commented that the LED luminaires were less glary, created less shadows, had a positive impact on visibility, and improved the overall appearance of the area. PNNL conducted an economic analysis and found that the Version 1 lamp produced annual energy savings of 955 kWh and energy cost savings of $76.39 per lamp at electricity rates of 6.5 cents per kWh and $105.03 at 11 cents per kWh. PNNL found that the Version 2 lamp produced annual energy savings of 991 kWh and energy cost savings of $79.26 per lamp at electricity rates of 6.5 cents per kWh and $108.98 at 11 cents per kWh. PNNL also calculated simple payback and found that Version 1 showed paybacks of 5.4 yrs at 6.5c/kWh and 4.1 yrs at 11c/kWh while Version 2 showed paybacks of 5.2 yrs at 6.5c/kWh and 3.9 yrs at 11c/kWh.

  16. Traffic Light Protocol: WHITE Traffic Light Protocol: WHITE (information may be distributed without restriction, subject to copyright controls.)

    E-Print Network [OSTI]

    Thomas, Andrew

    the event for their gain. The Threats: Internet watch groups and cyber security experts have already potential cyber threats please visit the Center for Internet Security website at CISecurity.org. #12;Traffic Light Protocol: WHITE Traffic Light Protocol: WHITE (information may be distributed without

  17. Intel Led OpenMP Training Session at NERSC This Wednesday March...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Led OpenMP Training Session at NERSC This Wednesday March 25 Intel Led OpenMP Training Session at NERSC This Wednesday March 25 March 24, 2015 by Katie Antypas (0 Comments) This...

  18. Fabrication of InGaP LEDs on a graded buffer substrate

    E-Print Network [OSTI]

    Martínez, Josué F

    2007-01-01T23:59:59.000Z

    Introduction: Computer display panels create a vast color palette by combining color from three light emitting diodes (LEDs), each producing red, green, or blue light. The light from these three LEDs is chosen so that the ...

  19. Have You Used LED Lighting? Tell Us About It. | Department of...

    Broader source: Energy.gov (indexed) [DOE]

    It. May 7, 2009 - 5:00am Addthis This week, John shared his experiences with light-emitting diode (LED) lighting. In a future blog, he'll share more about LED lighting. Have you...

  20. An Investigation into the Perception of Color under LED White Composite Spectra with Modulated Color Rendering

    E-Print Network [OSTI]

    O'Reilly, Una-May

    emitting diodes, LEDs. We examined seven LED white composite spectra with different color rendering of a pilot study that evaluates the perceptual impact of modulation of color rendering using multi-chip light

  1. Development and Industrialization of InGaN/GaN LEDs on Patterned...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of InGaNGaN LEDs on Patterned Sapphire Substrates for Low Cost Emitter Architecture Development and Industrialization of InGaNGaN LEDs on Patterned Sapphire...

  2. EERE FY 2008-2012 Budget: Weatherization and Intergovernmental...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    for energy savings covering 153 million square feet. Install 92,488 light-emitting diode (LED) traffic signals. Purchase or convert 6,434 alternative fuel vehicles....

  3. CX-005790: Categorical Exclusion Determination | Department of...

    Broader source: Energy.gov (indexed) [DOE]

    5) install lighting (occupancy) sensors in municipal buildings, and 6) install light emitting diode (LED) traffic signals throughout the city. DOCUMENT(S) AVAILABLE FOR DOWNLOAD...

  4. CX-000174: Categorical Exclusion Determination | Department of...

    Broader source: Energy.gov (indexed) [DOE]

    County Courthouse Energy Efficiency Retrofits, IT Server Virtualization, LED (light-emitting diode) Traffic Signal Upgrades, EnergyAudit & Energy Master Planning for Public &...

  5. CX-000169: Categorical Exclusion Determination | Department of...

    Broader source: Energy.gov (indexed) [DOE]

    Recycle cart promotion program, Residential and commercial conservation, LED (light-emitting diode) replacement for Traffic Signals, Smart Powerstrips, State Energy Program...

  6. CX-009173: Categorical Exclusion Determination | Department of...

    Broader source: Energy.gov (indexed) [DOE]

    and 4) complete ongoing conversion of all traffic and pedestrian signals to light emitting diode (LED). CX-009173.pdf More Documents & Publications CX-004974: Categorical...

  7. adding direct sunlight: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ERRONEOUSLY DURING DIRECT SUNLIGHT CONDITIONS BY RED-GREEN CiteSeer Summary: Light-emitting diode (LED) traffic signal indications have become increasingly popular in the United...

  8. CX-008190: Categorical Exclusion Determination | Department of...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    and Renewable Energy Energy Efficiency and Conservation Block Grant. 1) Light-emitting diode (LED) traffic signal retrofit, 2) fire house solar photovoltaic, 3) solar...

  9. Text-Alternative Version: Model Specification for LED Roadway Luminaires Webcast

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the "Model Specification for LED Roadway Luminaires" webcast, held November 15, 2011.

  10. Text-Alternative Version: Successful Selection of LED Streetlight Luminaires Webcast

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the "Successful Selection of LED Streetlight Luminaires" webcast, held March 6, 2013.

  11. TESLA-FEL 2007-03 Application of low cost GaAs LED as neutron

    E-Print Network [OSTI]

    neutrons in unbiased Gallium Arsenide (GaAs) Light Emitting Diodes (LED) resulted in a reduction Keywords: COTS components, Displacement damage, Electron Linear Accelerator, GaAs Light emitting diode (LED) Gallium Arsenide (GaAs) light emitting diode (LED) for the assessment of integrated neutron fluence

  12. UV-LED LITHOGRAPHY FOR 3-D HIGH ASPECT RATIO MICROSTRUCTURE PATTERNING

    E-Print Network [OSTI]

    in microfabrication. Table 1 compares the performance of UV-LEDs with a mercury lamp for several key parametersUV-LED LITHOGRAPHY FOR 3-D HIGH ASPECT RATIO MICROSTRUCTURE PATTERNING Jungkwun `JK' Kim*, Seung of Technology, Atlanta, GA, USA ABSTRACT This paper presents a UV lithography method that utilizes a UV-LED

  13. Color shift reduction of a multi-domain IPS-LCD using RGB-LED backlight

    E-Print Network [OSTI]

    Wu, Shin-Tson

    -emitting diodes (LEDs) and cold-cathode fluorescent lamp (CCFL) backlights. Simulation results indicateColor shift reduction of a multi-domain IPS- LCD using RGB-LED backlight Ruibo Lu, Qi Hong, Zhibing that the LED backlight exhibits a wider color gamut, better angular color uniformity, and 2-4X smaller static

  14. Issues, Models and Solutions for Triac Modulated Phase Dimming of LED Lamps

    E-Print Network [OSTI]

    Lehman, Brad

    Issues, Models and Solutions for Triac Modulated Phase Dimming of LED Lamps Dustin Rand (Raytheon Edison socket LED lamps directly from residential phase modulated dimmer switches. In order to explain brightness "White Light" LEDs have experts predicting that the "bright white replacement lamp" could trigger

  15. Electronic constant current and current pulse signal generator for nuclear instrumentation testing

    DOE Patents [OSTI]

    Brown, Roger A. (Amsterdam, NY)

    1994-01-01T23:59:59.000Z

    Circuitry for testing the ability of an intermediate range nuclear instrut to detect and measure a constant current and a periodic current pulse. The invention simulates the resistance and capacitance of the signal connection of a nuclear instrument ion chamber detector and interconnecting cable. An LED flasher/oscillator illuminates an LED at a periodic rate established by a timing capacitor and circuitry internal to the flasher/oscillator. When the LED is on, a periodic current pulse is applied to the instrument. When the LED is off, a constant current is applied. An inductor opposes battery current flow when the LED is on.

  16. Electronic constant current and current pulse signal generator for nuclear instrumentation testing

    DOE Patents [OSTI]

    Brown, R.A.

    1994-04-19T23:59:59.000Z

    Circuitry is described for testing the ability of an intermediate range nuclear instrument to detect and measure a constant current and a periodic current pulse. The invention simulates the resistance and capacitance of the signal connection of a nuclear instrument ion chamber detector and interconnecting cable. An LED flasher/oscillator illuminates an LED at a periodic rate established by a timing capacitor and circuitry internal to the flasher/oscillator. When the LED is on, a periodic current pulse is applied to the instrument. When the LED is off, a constant current is applied. An inductor opposes battery current flow when the LED is on. 1 figures.

  17. Emergency evacuation/transportation plan update: Traffic model development and evaluation of early closure procedures. Final report

    SciTech Connect (OSTI)

    NONE

    1993-10-28T23:59:59.000Z

    Prolonged delays in traffic experienced by Laboratory personnel during a recent early dismissal in inclement weather, coupled with reconstruction efforts along NM 502 east of the White Rock Wye for the next 1 to 2 years, has prompted Los Alamos National Laboratory (LANL) to re-evaluate and improve the present transportation plan and its integration with contingency plans maintained in other organizations. Facilities planners and emergency operations staff need to evaluate the transportation system`s capability to inefficiently and safely evacuate LANL under different low-level emergency conditions. A variety of potential procedures governing the release of employees from the different technical areas (TAs) requires evaluation, perhaps with regard to multiple emergency-condition scenarios, with one or more optimal procedures ultimately presented for adoption by Lab Management. The work undertaken in this project will hopefully lay a foundation for an on-going, progressive transportation system analysis capability. It utilizes microscale simulation techniques to affirm, reassess and validate the Laboratory`s Early Dismissal/Closure/Delayed Opening Plan. The Laboratory is required by Federal guidelines, and compelled by prudent practice and conscientious regard for the welfare of employees and nearby residents, to maintain plans and operating procedures for evacuation if the need arises. The tools developed during this process can be used outside of contingency planning. It is anticipated that the traffic models developed will allow site planners to evaluate changes to the traffic network which could better serve the normal traffic levels. Changes in roadway configuration, control strategies (signalization and signing), response strategies to traffic accidents, and patterns of demand can be modelled using the analysis tools developed during this project. Such scenarios typically are important considerations in master planning and facilities programming.

  18. A study and comparison of traffic assignment methods

    E-Print Network [OSTI]

    McIver, Jes David

    1956-01-01T23:59:59.000Z

    OF SCIENCE January 1956 Ma)or Sub]ect: Civil Engineering LIBRARY I S IS CIILLEOE OF TEXAS A STUDY AND COMPARISON OF TRAFFIC ASSIGNFIENT IIETHODS A Thesd. s by JES DAVID MCIVER Approved as to style and content by: p/ / ~ Chairman of Committee Head... Traffic Assignment by Brown's and Related Methods g8 LIST OF FIGURES Figure ~Ne ~Ttle Page Number Total . 'iotor Vehicle Travel in the United States Relation of Traffio on Raine Turnpike to That on U S 1, By Years 10 Traffic Diversion Curves...

  19. The impact of gasoline price changes on traffic safety: a time geography explanation Guangqing Chi a,

    E-Print Network [OSTI]

    Levinson, David M.

    The impact of gasoline price changes on traffic safety: a time geography explanation Guangqing Chi, United States a r t i c l e i n f o Keywords: Time geography Gasoline prices Traffic safety Traffic crashes Fatal crashes Space­time path a b s t r a c t The impact of gasoline price changes on traffic

  20. Visualization of Traffic Flow and Atmospheric Pollutant Flow in Urban Areas

    E-Print Network [OSTI]

    Tokyo, University of

    and air pollutants using polygons and translucent particles. The system is applied for public roads around.transport.iis.u-tokyo.ac.jp CCity modelity model Air pollutionAir pollution simsim.. TrafficTraffic simsim.. CCity modelity model Air pollutionAir pollution simsim.. TrafficTraffic simsim.. #12;

  1. Intelligent Cruise Control design based on a traffic flow specification

    E-Print Network [OSTI]

    Huandra, Rusli

    1998-01-01T23:59:59.000Z

    The principal objectives of the Automated Highway graphics. System (AHS), an Intelligent Transportation System (ITS) technology, are to increase the safety and through-put of the existing highway by traffic automation. Advanced Vehicle Control...

  2. accidents traffic: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    specifically, three distinct studies (more) OShields, Lara Lynn 2007-01-01 2 Does Daylight Savings Time Affect Traffic Accidents? Texas A&M University - TxSpace Summary: This...

  3. Decision support systems for automated terminal area air traffic control

    E-Print Network [OSTI]

    Pararas, John Demetrios

    1982-01-01T23:59:59.000Z

    This work studies the automation of the terminal area Air Traffic Management and Control (ATM/C) system. The ATM/C decision-making process is analyzed and broken down into a number of "automation functions". Each of these ...

  4. automated mixed traffic: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    technology, are to increase the safety and through-put of the existing highway by traffic automation. Advanced Vehicle Control... Huandra, Rusli 1998-01-01 46 Cognitive Engineering...

  5. Dynamic Traffic Assignment Incorporating Commuters’ Trip Chaining Behavior

    E-Print Network [OSTI]

    Wang, Wen

    2012-10-19T23:59:59.000Z

    through a fixed-point problem. However, they treated the travel time on links ideally as constants without considering the dynamic traffic conditions. Heydecker and Polak (2006) developed a model of tour scheduling with equilibrium analysis on congested...

  6. Evaluation of teenage driver understanding of traffic control devices

    E-Print Network [OSTI]

    Ford, Garry Lee

    1999-01-01T23:59:59.000Z

    This research documents the evaluation of teenage graphics. drivers with regards to their understanding of 53 traffic control devices. A multiple choice survey was developed and administered to a group of teenage drivers between 15 and 18 years...

  7. airport traffic: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    as a benchmark in the 4th International Planning Competition. Sebastian Trg; Jrg Hoffmann; Bernhard Nebel 2004-01-01 10 Towards a Market Mechanism for Airport Traffic Control...

  8. Intelligent Cruise Control design based on a traffic flow specification 

    E-Print Network [OSTI]

    Huandra, Rusli

    1998-01-01T23:59:59.000Z

    The principal objectives of the Automated Highway graphics. System (AHS), an Intelligent Transportation System (ITS) technology, are to increase the safety and through-put of the existing highway by traffic automation. Advanced Vehicle Control...

  9. Notes and comments Impacts of traffic heterogeneity on roadside air

    E-Print Network [OSTI]

    Illinois at Chicago, University of

    a discrete traffic kinematic wave model formulated by Daganzo (1994, 1995). This model provides a cell-based solution, termed the cell-transmission (CT) recipe, to the kinematic wave model. It introduces a simplistic

  10. Using Map Matching for an Online Traffic Congestion Application 

    E-Print Network [OSTI]

    Day, Madeleine

    2010-11-24T23:59:59.000Z

    Optimising the flow of traffic on road networks can be achieved through sharing information about congestion events to road users. Using GPS sensors to track vehicle movements can provide information to monitor speeds ...

  11. Development and Evaluation of a Novel Traffic Friendly Commuter Vehicle

    E-Print Network [OSTI]

    Minnesota, University of

    Development and Evaluation of a Novel Traffic Friendly Commuter Vehicle Rajesh Rajamani Department What solutions do researchers in the automotive industry and researchers in the vehicle dynamics lanes - Vehicles will travel together in closely- packed "platoons". Dedicated to automated vehicles

  12. Design and testing of a roadside traffic threat alerting mechanism

    E-Print Network [OSTI]

    Powale, Pallavi

    2013-01-01T23:59:59.000Z

    Every year, law enforcement officials, emergency personnel, and other workers stopped in traffic outside their vehicles are struck by inattentive drivers. Until now, most efforts to prevent these types of accidents have ...

  13. Characterization of network traffic on a local area network

    E-Print Network [OSTI]

    Suravarapu, Prasad Devi

    1995-01-01T23:59:59.000Z

    In this thesis we analyze network traffic on a local area network in an academic environment. We analyze the trace based on transport-level and network-level applications. Networks conversations are studied using the newly developed packet...

  14. Anti-eavesdropping communication layer to protect against traffic analysis

    E-Print Network [OSTI]

    Shen, Yiping

    2002-01-01T23:59:59.000Z

    In this thesis, we present unicast and multicast protocols to resist eavesdropping and traffic profiling of group communications. At the application layer, we propose a secret-sharing approach for the exchange of shared keys. That is, multicast...

  15. Optimization Online - Ship Traffic Optimization for the Kiel Canal

    E-Print Network [OSTI]

    Elisabeth LĂĽbbecke

    2014-12-01T23:59:59.000Z

    Dec 1, 2014 ... This leads us to construct a fast online heuristic. The STCP ... In view of computational experiments on real traffic data expert planners approved that our combinatorial algorithm is well-suited for this decision support. With the ...

  16. Simulations of highway traffic with various degrees of automation

    SciTech Connect (OSTI)

    Doss, E.; Hanebutte, U.; Vitela, J.; Brown-VanHoozer, A.; Ewing, T.; Tentner, A.

    1996-10-01T23:59:59.000Z

    A traffic simulator to study highway traffic under various degrees of automation is being developed at Argonne National Laboratory (ANL). The key components of this simulator include a global and a local Expert Drive Mode, a human factor study and a graphical user interface. Further, an Autonomous Intelligent Cruise Control (AICC) which is based on a neural network controller is described and results for a typical driving scenario are given.

  17. Simulation of vehicle traffic on an automatic highway system.

    SciTech Connect (OSTI)

    Hanebutte, U.; Doss, E.; Ewing, T.; Tentner, A.; Technology Development

    1998-01-01T23:59:59.000Z

    A traffic simulator has been developed at Argonne National Laboratory to study highway traffic under various degrees of automation. The key components of this simulator include a global and a local Expert Driver Model, a human factor study, and a graphical user interface. Furthermore, an Autonomous Intelligent Cruise Control, which is based on a neural network controller, is described and results for two typical driving scenarios are given.

  18. Structural and safety characteristics and warrants for highway traffic barriers 

    E-Print Network [OSTI]

    Kohutek, Terry Lee

    1975-01-01T23:59:59.000Z

    Ross Highway traffic barriers are highway appurtenances that provide vehicle occupants with a relative degree of protection from roadside hazards and from errant vehicles encroaching across a median. The six basic types of traffic barr1ers are roads... are decision criteria that 1dentify sites along highways that need traff1c barrier installations. Structural and safety character- istics of the barr1ers refer to the impact performance, the structural integrity, and the safety of the vehicle occupants upon...

  19. Structural and safety characteristics and warrants for highway traffic barriers

    E-Print Network [OSTI]

    Kohutek, Terry Lee

    1975-01-01T23:59:59.000Z

    Ross Highway traffic barriers are highway appurtenances that provide vehicle occupants with a relative degree of protection from roadside hazards and from errant vehicles encroaching across a median. The six basic types of traffic barr1ers are roads... are decision criteria that 1dentify sites along highways that need traff1c barrier installations. Structural and safety character- istics of the barr1ers refer to the impact performance, the structural integrity, and the safety of the vehicle occupants upon...

  20. Design and analysis of an ATM network traffic security device

    E-Print Network [OSTI]

    Teodor, Dan Cristian

    1997-01-01T23:59:59.000Z

    and retransmit the network traffic from one ATM network switch output port. The Receivers queue the incoming data from the ATM network switch and present the data to the Analysis Modules in manageable pieces. The Analysis Modules capture the data from... at an exponential rate. With the continuation of this growth, the requirements of providing uniform security management will become more and more difficult to manage without occupying a significant portion of the network traffic capability available to the end...

  1. Resolving small signal measurements in experimental plasma environments using calibrated subtraction of noise signals

    SciTech Connect (OSTI)

    Fimognari, P. J., E-mail: PJFimognari@XanthoTechnologies.com; Demers, D. R. [Xantho Technologies, LLC, Madison, Wisconsin 53705 (United States); Chen, X. [Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee 37830 (United States); Schoch, P. M. [Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)

    2014-11-15T23:59:59.000Z

    The performance of many diagnostic and control systems within fusion and other fields of research are often detrimentally affected by spurious noise signals. This is particularly true for those (such as radiation or particle detectors) working with very small signals. Common sources of radiated and conducted noise in experimental fusion environments include the plasma itself and instrumentation. The noise complicates data analysis, as illustrated by noise on signals measured with the heavy ion beam probe (HIBP) installed on the Madison Symmetric Torus. The noise is time-varying and often exceeds the secondary ion beam current (in contrast with previous applications). Analysis of the noise identifies the dominant source as photoelectric emission from the detectors induced by ultraviolet light from the plasma. This has led to the development of a calibrated subtraction technique, which largely removes the undesired temporal noise signals from data. The advantages of the technique for small signal measurement applications are demonstrated through improvements realized on HIBP fluctuation measurements.

  2. T.T.T.Nguyen, G.Armitage, A Survey of Techniques for Internet Traffic Classification using Machine Learning A Survey of Techniques for Internet Traffic

    E-Print Network [OSTI]

    Armitage, Grenville

    of their various business goals. Traffic classification may be a core part of automated intrusion detection systemsT.T.T.Nguyen, G.Armitage, A Survey of Techniques for Internet Traffic Classification using Machine Learning A Survey of Techniques for Internet Traffic Classification using Machine Learning Thuy T.T. Nguyen

  3. WhiteOptics' Low-Cost Reflector Composite Boosts LED Fixture Efficiency

    Broader source: Energy.gov [DOE]

    With the help of DOE funding, WhiteOptics has developed a composite coating that can be used to improve efficiency in backlit, indirect, and cavity-mixing LED luminaire designs by maximizing light reflection and output. The highly diffuse coating, which is based on a novel high-reflectance particle technology, allows for uniform distribution of light without exaggerating the point-source nature of the LEDs, and is intended to offer an overall system cost-improving solution for LED optics.

  4. LED exit signs: Improved technology leads the way to energy savings

    SciTech Connect (OSTI)

    Sardinsky, R.; Hawthorne, S.

    1994-12-31T23:59:59.000Z

    Recent innovations in light-emitting diode (LED) exit signs may make LED signs the best choice among the energy efficient options available. In the past, LED signs have offered low power consumption, projected long lamp life, and low maintenance requirements. Now, the best of the LED signs also offer improved optical designs that reduce their already low power consumption while improving visibility and appearance, and even reduce their cost. LED exit signs are gaining market share, and E Source expects this technology to eventually dominate over incandescent, compact fluorescent, and electroluminescent signs. More research is needed, however, to confirm manufacturers` claims of 20-year operating lives for LED signs. Conservative estimates place the number of exit signs in US buildings at about 40 million. Although each sign represents a very small part of a building`s load, exit signs are ready targets for energy efficiency upgrades -- they operate continuously and most use inefficient incandescent sources. With an LED sign, annual energy and maintenance costs can be reduced by more than 90 percent compared to a typical incandescent sign. Low annual costs help to offset the LED sign`s relatively high first cost. More than 25 utilities offer DSM incentives for energy efficient exit signs, and efficient alternatives are becoming more readily available. Recent improvements in optical designs enable many LED signs to visually out perform other sources. In addition to these benefits, LED exit signs have lower life cycle cost than most other options. The biggest barrier to their success, however, is that their first cost has been considerably higher than competing technologies. LED sign prices are falling rapidly, though, because manufacturers are continually improving optical designs of the fixtures to use fewer LEDs and thus even less energy while providing better performance.

  5. Philips Lumileds Achieves 139 lm/W in a Neutral White LED

    Broader source: Energy.gov [DOE]

    Philips Lumileds' LUXEON Rebel LED can now deliver 139 lm/W in a neutral white LED. The top bin LED, developed with a single InGaN die and phosphor conversion, shows high-performance characteristics up to 139 lm/W and 138 lumens at 350 mA, with a forward voltage of 2.83 V. The CCT of the device is 5385K and the CRI is 70.

  6. Panos D. Prevedouros, PhD, Asc. Professor of Transportation Engineering, Department of Civil and Environmental Engineering, UH-Manoa pdp@hawaii.edu January 2004 This is a comprehensive but not an exhaustive list of suggestions for easing traffic congest

    E-Print Network [OSTI]

    Prevedouros, Panos D.

    , these funds can be used to improve the City's extensive traffic signal system, the Traffic Control Center the Liliha St. on ramp and the Pali Hwy. off-ramp. o Control the inflow of the Vineyard Blvd. and Ward Ave for buses and HOV!HOT). o If the above viaduct can't be done, then re-design the Sand Island Access Road

  7. Text-Alternative Version: MSSLC Member Case Studies- LED Street Lighting Programs Webinar

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the "MSSLC Member Case Studies - LED Street Lighting Programs" webcast, held May 8, 2013.

  8. Text Alternative Version: Life-Cycle Assessment of Energy and Environmental Impacts of LED Lighting Products

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the "Life-Cycle Assessment of Energy and Environmental Impacts of LED Lighting Products" webcast, held March 28, 2013.

  9. New Family of Tiny Crystals Glow Bright in LED Lights | Advanced...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    crystals that glow different colors may be the missing ingredient for white light-emitting diode (LED) lighting that illuminates homes and offices as effectively as natural...

  10. Scalable Light Module for Low-Cost, High Efficiency LED Luminaires...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Low-Cost, High Efficiency LED Luminaires More Documents & Publications Low-Cost Light-Emitting Diode Luminaire for General Illumination 2015 Project Portfolio 2014 Solid-State...

  11. Text-Alternative Version: CALiPER Series 21 on LED Linear Lamps and Troffer Lighting

    Broader source: Energy.gov [DOE]

    Following is a text version of a video about CALiPER Application Report Series 21 on LED Linear Lamps and Troffer Lighting.

  12. Text-Alternative Version: LED Replacement Lamps: Current Performance and the Latest on ENERGY STAR®

    Broader source: Energy.gov [DOE]

    Below is the text-alternative version of the LED Replacement Lamps: Current Performance and the Latest on ENERGY STAR® webcast.

  13. LED Linear Lamps and Troffer Lighting: CALiPER Report Series 21

    ScienceCinema (OSTI)

    Beeson, Tracy; Miller, Naomi

    2014-06-23T23:59:59.000Z

    Video about CALiPER Report Series 21 on LED Linear Lamps and Troffer Lighting, featuring interviews with Tracy Beeson and Naomi Miller of Pacific Northwest National Laboratory.

  14. Researchers Say They've Solved the Mystery of LED Lighting "Droop...

    Broader source: Energy.gov (indexed) [DOE]

    Sciences Team. Despite being cool, ultra-efficient and long lasting, the light-emitting diode (LED) faces a problem called "efficiency droop." New findings from simulations...

  15. LEDS Tool: Step-By-Step Guidance to a Long-Term Framework for...

    Open Energy Info (EERE)

    OpenEI Keyword(s): LEDS Guidance Developing Implementing Process Language: "English, Spanish; Castilian" is not in the list of possible values (Abkhazian, Achinese, Acoli,...

  16. 2015 DOE SSL R&D Workshop LED Topic Table Questions to Consider

    Broader source: Energy.gov [DOE]

    This document was distributed during the LED Topic Table portion of the DOE SSL R&D Workshop and aimed to prompt discussion on the following topics:

  17. A rigorous treatment of a follow-the-leader traffic model with traffic lights present

    SciTech Connect (OSTI)

    Argall, Brenna; Cheleshkin, Eugene; Greenberg, J.M.; Hinde, Colin; Lin, Pei-Jen

    2003-07-16T23:59:59.000Z

    Traffic flow on a unidirectional roadway in the presence of traffic lights is modeled. Individual car responses to green, yellow, and red lights are postulated and these result in rules governing the acceleration and deceleration of individual cars. The essence of the model is that only specific cars are directly affected by the lights. The other cars behave according to simple follow-the-leader rules which limit their speed by the spacing between it and the car directly ahead. The model has a number of desirable properties; namely cars do not run red lights, cars do not smash into one another, and cars exhibit no velocity reversals. In a situation with multiple lights operating in-phase we get, after an initial startup period, a constant number of cars through each light during any green-yellow period. Moreover, this flux is less by one or two cars per period than the flux obtained in discretized versions of the idealized Lighthill, Whitham, Richards model which allows for infinite accelerations.

  18. TRUE COLORS: LEDS AND THE RELATIONSHIP BETWEEN CCT, CRI, OPTICAL SAFETY, MATERIAL DEGRADATION, AND PHOTOBIOLOGICAL STIMULATION

    SciTech Connect (OSTI)

    Royer, Michael P.

    2014-08-30T23:59:59.000Z

    This document analyzes the optical, material, and photobiological hazards of LED light sources compared to conventional light sources. It documents that LEDs generally produce the same amount of blue light, which is the primary contributor to the risks, as other sources at the same CCT. Duv may have some effect on the amount of blue light, but CRI does not.

  19. The evolving price of household LED lamps: Recent trends and historical comparisons for the US market

    SciTech Connect (OSTI)

    Gerke, Brian F.; Ngo, Allison T.; Alstone, Andrea L.; Fisseha, Kibret S.

    2014-10-14T23:59:59.000Z

    In recent years, household LED light bulbs (LED A lamps) have undergone a dramatic price decline. Since late 2011, we have been collecting data, on a weekly basis, for retail offerings of LED A lamps on the Internet. The resulting data set allows us to track the recent price decline in detail. LED A lamp prices declined roughly exponentially with time in 2011-2014, with decline rates of 28percent to 44percent per year depending on lumen output, and with higher-lumen lamps exhibiting more rapid price declines. By combining the Internet price data with publicly available lamp shipments indices for the US market, it is also possible to correlate LED A lamp prices against cumulative production, yielding an experience curve for LED A lamps. In 2012-2013, LED A lamp prices declined by 20-25percent for each doubling in cumulative shipments. Similar analysis of historical data for other lighting technologies reveals that LED prices have fallen significantly more rapidly with cumulative production than did their technological predecessors, which exhibited a historical decline of 14-15percent per doubling of production.

  20. CONSTRUCTING AN ELASTIC TOUCH PANEL WITH EMBEDDED IR-LEDS USING SILICONE RUBBER

    E-Print Network [OSTI]

    Tanaka, Jiro

    CONSTRUCTING AN ELASTIC TOUCH PANEL WITH EMBEDDED IR-LEDS USING SILICONE RUBBER Yuichiro Sakamoto a technique for the construction of an elastic touch panel using silicone rubber. The technique is similar is made of transparent silicone rubber rather than acrylic. Moreover, we embedded infrared LEDs within

  1. Department of Mechanical Engineering Spring 2013 Lumax Lighting 2: LED Industrial High Bay Light Fixture

    E-Print Network [OSTI]

    Demirel, Melik C.

    PENNSTATE Department of Mechanical Engineering Spring 2013 Lumax Lighting 2: LED Industrial High Bay Light Fixture Overview The problem that our sponsor, Rich Taylor, presented to the team was to design a light fixture for an industrial setting using high power LED lights. The challenge

  2. Cree's High-Power White LED Delivers 121 lm/W

    Broader source: Energy.gov [DOE]

    Cree's commercial high-power white LEDs can now deliver 121 lm/W at 35A/cm2 current density. These particular Cree XLamp® XP-G LEDs deliver 267 lumens at a drive current of 700 mA and an operating...

  3. LED Lighting Flicker and Potential Health Concerns: IEEE Standard PAR1789 Update

    E-Print Network [OSTI]

    Lehman, Brad

    LED Lighting Flicker and Potential Health Concerns: IEEE Standard PAR1789 Update Arnold Wilkins for mitigating health risks to viewers" has been formed to advise the lighting industry, ANSI/NEMA, IEC, EnergyStar and other standards groups about the emerging concern of flicker in LED lighting. This paper introduces

  4. Proposal -Interactive City Lighting LED based lighting systems have enabled radically new

    E-Print Network [OSTI]

    Proposal - Interactive City Lighting Abstract LED based lighting systems have also be integrated with sensors and smart environments. This has opened up a new world. The use of the LED as a potential means for providing interactive city lighting for social

  5. Largest-area Photonic Crystal LED Fabricated Demonstrates Uniform Light Emission

    Broader source: Energy.gov [DOE]

    Lumileds Lighting, the University of New Mexico, and Sandia National Laboratories teamed to demonstrate uniform light emission from the largest-area III-Nitride photonic crystal LED (1 x 1 mm2) ever fabricated. Most previous photonic crystal LED research has relied on small-area patterns written by slow, serial-writing electron-beam lithography.

  6. An Efficient LED System-in-Module for General Lighting Applications

    SciTech Connect (OSTI)

    None

    2008-09-14T23:59:59.000Z

    The objective of the project was to realize an LED-based lighting technology platform for general illumination, starting with LED chips, and integrating the necessary technologies to make compact, user-friendly, high-efficiency, energy-saving sources of controlled white (or variable-colored) light. The project is to build the system around the LEDs, and not to work on the LEDs themselves, in order that working products can be introduced soon after the LEDs reach suitable efficiency for mass-production of high-power light sources for general illumination. Because the light sources are intended for general illumination, color must be accurately maintained, requiring feedback control in the electronics. The project objective has been realized and screw base demonstrators, based on the technology developed in the project, have been built.

  7. Eco-Approach and Departure Techniques for Connected Vehicles at Signalized Traffic Intersections

    E-Print Network [OSTI]

    Xia, Haitao

    2014-01-01T23:59:59.000Z

    Time Information Synthesis) ConOps and Modeling Workshop?,Concept of Operations (ConOps) documents for three high-

  8. Development and evaluation of an arterial adaptive traffic signal control system using reinforcement learning

    E-Print Network [OSTI]

    Xie, Yuanchang

    2009-05-15T23:59:59.000Z

    control. Two different implementation schemes are considered. The first scheme uses a fixed phase sequence and variable cycle length, while the second one optimizes phase sequence in real time and is not constrained to the concept of cycle. Both schemes...

  9. 78.1: Ultra Compact Polarization Recycling System for White Light LED based Pico-Projection System

    E-Print Network [OSTI]

    78.1: Ultra Compact Polarization Recycling System for White Light LED based Pico-Projection System polarization recycling system, for white light LED based projectors, is proposed. White light LED is applied. In this paper, we propose an ultra compact polarization recycling system for white light LED based projection

  10. Critical enhancements of a dynamic traffic assignment model for highly congested, complex urban network

    E-Print Network [OSTI]

    Wei, Zheng, S.M. Massachusetts Institute of Technology

    2010-01-01T23:59:59.000Z

    To accurately replicate the highly congested traffic situation of a complex urban network, significant challenges are posed to current simulation-based dynamic traffic assignment (DTA) models. This thesis discusses these ...

  11. advanced automation system air traffic control: Topics by E-print...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    technology, are to increase the safety and through-put of the existing highway by traffic automation. Advanced Vehicle Control... Huandra, Rusli 1998-01-01 56 Post: Air Traffic...

  12. Rethinking Internet Traffic Management: From Multiple Decompositions to a Practical Protocol

    E-Print Network [OSTI]

    Singh, Jaswinder Pal

    management spans congestion control (at end hosts), routing protocols (on routers), and traffic engineering (by network operators). Historically, this division of functionality evolved organically- tures of the algorithms, we construct TRUMP: a traffic man- agement protocol that is distributed

  13. Utilizing Correlations to Compress Time-Series in Traffic Monitoring Sensor Networks

    E-Print Network [OSTI]

    Martin, Ralph R.

    at Ł20bn. In urban areas, transport is the major source of carbon dioxide emissions, and traffic Cambridge testbed (Figure 1) and the spatio- temporal properties of a real traffic dataset. Section III

  14. A noise-tolerant traffic sign recognition method based on color images

    E-Print Network [OSTI]

    Ahmad, Akram

    1995-01-01T23:59:59.000Z

    Devising a pattern recognition methodology for traffic sign images captured in noisy outdoor environments poses a challenging problem. Such a method has to cope with occlusion noise as when part of the region of interest (in this case, the traffic...

  15. Methods and systems for detecting abnormal digital traffic

    DOE Patents [OSTI]

    Goranson, Craig A [Kennewick, WA; Burnette, John R [Kennewick, WA

    2011-03-22T23:59:59.000Z

    Aspects of the present invention encompass methods and systems for detecting abnormal digital traffic by assigning characterizations of network behaviors according to knowledge nodes and calculating a confidence value based on the characterizations from at least one knowledge node and on weighting factors associated with the knowledge nodes. The knowledge nodes include a characterization model based on prior network information. At least one of the knowledge nodes should not be based on fixed thresholds or signatures. The confidence value includes a quantification of the degree of confidence that the network behaviors constitute abnormal network traffic.

  16. Dynamic programming applied to maximizing traffic flow in parallel systems

    E-Print Network [OSTI]

    Anderson, Gerald Lee

    1967-01-01T23:59:59.000Z

    Solution of the problem The Triple-Route Model 33 CHAPTER I INTRODUCTION The control of traffic flow and congestion in freeway systems is a matter of increasing importance at a time when it. has become evident that it is impossible to construct... enough urban highway- to satisfy all of the traffic demand. It is necessary to seek ways to make more efficient u. e of existing freeways. Nattleworth (1, 2) and others (3, 4, 5, 6) have discussed various aspects of the control of freeway systems...

  17. Quality and Performance of LED Flashlights in Kenya: Common End User Preferences and Complaints

    SciTech Connect (OSTI)

    Tracy, Jenny; Jacobson, Arne; Mills, Evan

    2009-09-14T23:59:59.000Z

    Flashlights that use LED technology have quickly emerged as the dominant source of portable lighting in Kenya. While flashlights do not normally provide a substitute for kerosene and other highly inefficient fuels, they are an important early manifestation of LED lighting in the developing world that can serve as a platform - or deterrent - to the diffusion of the technology into the broader off-grid lighting market. The lead acid batteries embedded in flashlights also represent an important source of hazardous waste, and flashlight durability is thus an important determinant of the rate of waste disposal. Low-cost LED flashlights with prices from $1 to $4 are now widely available in shops and markets throughout Kenya. The increased penetration of LED technology in the flashlight market is significant, as over half of all Kenyan households report owning a flashlight (Kamfor, 2002). While this shift from conventional incandescent technology to modern LEDs may appear to be a promising development, end users that our research team interviewed expressed a number of complaints about the quality and performance of these new flashlights. This raises concerns about the interests of low-income flashlight users, and it may also indicate the onset of a broader market spoiling effect for off-grid lighting products based on LED technology (Mills and Jacobson, 2008; Lighting Africa, 2007). The quality of low-cost LED flashlights can contribute to market spoiling because these products appear to represent the first contact that most Kenyans have with LED technology. In this report, our team uses interviews with 46 end users of flashlights to collect information about their experiences, perceptions, and preferences. We focus especially on highlighting common complaints from respondents about the flashlights that they have used, as well as on noting the features that they indicated were important when evaluating the quality of a flashlight. In previous laboratory tests, researchers from our team found a wide range of quality and performance among battery powered LED lights (Granderson, et al. 2008).

  18. U-134: Apache Traffic Server Host Header Processing Flaw Lets Remote Users Deny Service

    Broader source: Energy.gov [DOE]

    A vulnerability was reported in Apache Traffic Server. A remote user can cause denial of service conditions.

  19. Boise Air Traffic Control Tower: High Performance and sustainable Building Guiding Principles Technical Assistance

    SciTech Connect (OSTI)

    Fowler, Kimberly M.; Goel, Supriya; Henderson, Jordan W.

    2013-09-01T23:59:59.000Z

    Overview of energy efficiency opportunities for new FAA tower construction using the Boise Air Traffic Control Tower as an example.

  20. Philips Lumileds Is Exploring the Use of Silicon Substrates to Lower the Cost of LEDs

    Broader source: Energy.gov [DOE]

    With the help of DOE funding, Philips Lumileds is exploring the use of nitride epitaxy on 150mm silicon substrates to produce low-cost, warm-white, high-performance general-illumination LEDs. Most LEDs are made with C-plane sapphire substrates, but silicon—at roughly half a penny per square millimeter—is much cheaper, and it's also easier to obtain. Philips Lumileds is attempting to adapt the use of silicon to the manufacture of LEDs, drawing upon the knowledge base and depreciated equipment of the computer industry, which has been using silicon substrates for decades.

  1. High Efficiency m-plane LEDs on Low Defect Density Bulk GaN Substrates

    SciTech Connect (OSTI)

    David, Aurelien

    2012-10-15T23:59:59.000Z

    Solid-state lighting is a key technology for reduction of energy consumption in the US and worldwide. In principle, by replacing standard incandescent bulbs and other light sources with sources based on light-emitting diodes (LEDs), ultimate energy efficiency can be achieved. The efficiency of LEDs has improved tremendously over the past two decades, however further progress is required for solid- state lighting to reach its full potential. The ability of an LED at converting electricity to light is quantified by its internal quantum efficiency (IQE). The material of choice for visible LEDs is Gallium Nitride (GaN), which is at the basis of blue-emitting LEDs. A key factor limiting the performance of GaN LEDs is the so-called efficiency droop, whereby the IQE of the LED decreases significantly at high current density. Despite decades of research, efficiency droop remains a major issue. Since high-current operation is necessary for practical lighting applications, reducing droop is a major challenge for the scientific community and the LED industry. Our approach to solving the droop issue is the use of newly available low-defect-density bulk GaN non-polar substrates. In contrast to the standard foreign substrates (sapphire, silicon carbide, silicon) used in the industry, we have employed native bulk GaN substrates with very low defect density, thus ensuring exquisite material quality and high IQE. Whereas all commercial LEDs are grown along the c-plane crystal direction of GaN, we have used m-plane non-polar substrates; these drastically modify the physical properties of the LED and enable a reduction of droop. With this approach, we have demonstrated very high IQE performance and low droop. Our results focused on violet and blue LEDs. For these, we have demonstrated very high peak IQEs and current droops of 6% and 10% respectively (up to a high current density of 200A.cm-2). All these results were obtained under electrical operation. These high IQE and low droop values are in line with the program’s milestones. They demonstrate that bulk non-polar GaN substrates represent a disruptive technology for LED performance. Application of this technology to real-world products is feasible, provided that the cost of GaN substrates is compatible with the market’s requirement.

  2. LED Provides Effective and Efficient Parking Area Lighting at the NAVFAC Engineering Service Center

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels DataDepartment of Energy Your Density Isn't YourTransport(FactDepartment ofLetter Report:40PM toLED Lighting Facts LED LightingOutdoorLED

  3. Gasoline price effects on traffic safety in urban and rural areas: Evidence from Minnesota, 19982007

    E-Print Network [OSTI]

    Levinson, David M.

    Gasoline price effects on traffic safety in urban and rural areas: Evidence from Minnesota, 1998 February 2012 Received in revised form 3 May 2013 Accepted 24 May 2013 Keywords: Gasoline prices Traffic examines the role of gasoline prices in the occurrence of traffic crashes. However, no studies have

  4. Integration of an Aggregate Flow Model with a Traffic Flow Simulator

    E-Print Network [OSTI]

    Integration of an Aggregate Flow Model with a Traffic Flow Simulator Robert Hoffman , Dengfeng Sun restrictions to aircraft movement are applied by air traffic controllers and traffic managers in response to demand overages or capacity shortfalls in sectors of airspace. To estimate and assess the efficiency

  5. Coupling traffic models on networks and urban dispersion models for simulating sustainable

    E-Print Network [OSTI]

    Ceragioli, Francesca

    models for modeling and testing different traffic scenarios, in order to define the impact on air quality it with the urban dispersion model Sirane. Keywords: urban air quality, macroscopic traffic models, road networks, pollutant dispersion models, traffic emissions control. AMS subject classification: 35L65, 35L67, 60K30, 90B

  6. Bounding Peer-to-Peer Upload Traffic in Client Networks Chun-Ying Huang

    E-Print Network [OSTI]

    Chen, Sheng-Wei

    interest. However, as the amount of peer-to- peer traffic increases, a network administrator would like for such network traffic. Second, as any one can develop their own protocols, even if network administratorsBounding Peer-to-Peer Upload Traffic in Client Networks Chun-Ying Huang National Taiwan University

  7. Realistic network traffic profile generation: theory and practice Antoine Varet1

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , "realistic behavior" means to generate traffic similar to the traffic a network administrator can captureRealistic network traffic profile generation: theory and practice Antoine Varet1 & Nicolas Larrieu1-mail: nicolas.larrieu@enac.fr Abstract Network engineers and designers need additional tools to generate network

  8. weber, evans, moser, and newell Air Traffic Management Decision Support During Convective Weather

    E-Print Network [OSTI]

    Reuter, Martin

    · weber, evans, moser, and newell Air Traffic Management Decision Support During Convective WeatherTraffic Management Decision Support During Convective Weather Mark E. Weber, James E. Evans, William R. Moser algorithm. #12;· weber, evans, moser, and newell Air Traffic Management Decision Support During Convective

  9. Review of Urban Bicyclists' Intake and Uptake of Traffic-Related Air Pollution

    E-Print Network [OSTI]

    Bertini, Robert L.

    Review of Urban Bicyclists' Intake and Uptake of Traffic-Related Air Pollution ALEXANDER Y. BIGAZZI- clists may experience increased inhalation of traffic-related air pollutants. Bicyclists have two to five regarding urban bicyclists' intake and uptake of traffic-related air pollution and to identify key knowledge

  10. Review of Urban Bicyclists' Intake and Uptake of Traffic-Related Air Pollution

    E-Print Network [OSTI]

    Bertini, Robert L.

    1 Review of Urban Bicyclists' Intake and Uptake of Traffic-Related Air Pollution Alexander Y of Traffic-Related Air Pollution Abstract Bicycling as a mode of transportation is enjoying a boost in many while bicycling, bicyclists may experience increased inhalation of traffic-related air pollutants

  11. Automatic Model Classification of Measured Internet Traffic Yi Zeng and Thomas M. Chen

    E-Print Network [OSTI]

    Chen, Thomas M.

    issues for future work. II. MODEL-LIBRARY TRAFFIC CLASSIFICATION Many traffic models have been developed Model 2 module ... Model library Fig. 1. General model classification system In the general case with NAutomatic Model Classification of Measured Internet Traffic Yi Zeng and Thomas M. Chen Department

  12. Air Traffic Complexity Resolution in Multi-Sector Planning Using CP

    E-Print Network [OSTI]

    Flener, Pierre

    Air Traffic Complexity Resolution in Multi-Sector Planning Using CP Pierre Flener1 Justin Pearson1 Programming for ATC & ATM, Brétigny (France), 2 December 2008 #12;Objective Air Traffic Complexity Complexity Resolution A CP Model Experiments Conclusion Outline 1 Objective 2 Air Traffic Complexity 3 Complexity

  13. Air traffic complexity and the interacting particle system method: An integrated approach for collision risk estimation

    E-Print Network [OSTI]

    Del Moral , Pierre

    Air traffic complexity and the interacting particle system method: An integrated approach explore the possibility of using air traffic complexity metrics to accelerate the Interacting Particle to assess the performance and impact of, e.g., possible modifications of the current air traffic management

  14. The inhomogeneous kinematic wave traffic flow model as a resonant nonlinear system

    E-Print Network [OSTI]

    Mease, Kenneth D.

    The inhomogeneous kinematic wave traffic flow model as a resonant nonlinear system December, 2000 W 95616 Abstract The kinematic wave traffic flow model for an inhomogeneous road is studied as a resonant conform to expectations. Introduction The kinematic wave traffic flow model of LWR was introduced

  15. Self-learning IP Traffic Classification based on Statistical Flow Characteristics

    E-Print Network [OSTI]

    Zander, Sebastian

    and intrusion detection. The most common identification technique based on the inspection of `known port numbers or encrypted traffic. The authors of [1] propose signature-based methods to classify P2P traffic. AlthoughSelf-learning IP Traffic Classification based on Statistical Flow Characteristics Sebastian Zander1

  16. Member Case Studies: LED Street Lighting Programs in Algona (IA), Asheville (NC), and Boston (MA)

    Broader source: Energy.gov [DOE]

    This May 8, 2013 webcast featured presentations from DOE Municipal Solid-State Street Lighting Consortium member cities about their experiences with LED street lighting. Presenters John Bilsten of...

  17. LED Linear Lamps and Troffer Lighting: CALiPER Report Series 21

    Broader source: Energy.gov [DOE]

    View the video about CALiPER Report Series 21 on LED Linear Lamps and Troffer Lighting, featuring interviews with Tracy Beeson and Naomi Miller of Pacific Northwest National Laboratory.

  18. Transcranial LED therapy for cognitive dysfunction in chronic, mild traumatic brain injury: Two case reports

    E-Print Network [OSTI]

    Hamblin, Michael R.

    Two chronic, traumatic brain injury (TBI) cases are presented, where cognitive function improved following treatment with transcranial light emitting diodes (LEDs). At age 59, P1 had closed-head injury from a motor vehicle ...

  19. Deposition of colloidal quantum dots by microcontact printing for LED display technology

    E-Print Network [OSTI]

    Kim, LeeAnn

    2006-01-01T23:59:59.000Z

    This thesis demonstrates a new deposition method of colloidal quantum dots within a quantum dot organic light-emitting diode (QD-LED). A monolayer of quantum dots is microcontact printed as small as 20 ,Lm lines as well ...

  20. Life-Cycle Assessment of Energy and Environmental Impacts of LED Lighting Products

    Broader source: Energy.gov [DOE]

    This March 28, 2013 webcast reviewed DOE's recently completed three-part study of the life-cycle energy and environmental impacts of LED lighting products relative to incandescent and CFL...

  1. Psychophysical evaluations of modulated color rendering for energy performance of LED-based architectural lighting

    E-Print Network [OSTI]

    Thompson, Maria do Rosário

    2007-01-01T23:59:59.000Z

    This thesis is focused on the visual perception evaluation of colors within an environment of a highly automated lighting control strategy. Digitally controlled lighting systems equipped with light emitting diodes, LEDs, ...

  2. Quality and Performance of LED Flashlights in Kenya: Common End User Preferences and Complaints

    E-Print Network [OSTI]

    Tracy, Jenny

    2010-01-01T23:59:59.000Z

    at ensure the success of the off-grid lighting market. Theand E. Mills. 2008. "Measured Off? Grid LED Lighting Systemtechnology into the broader off-grid lighting market. The

  3. adjustable red-green-blue led: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    or by combining green and red phosphors on a background consisting of a blue-light emitting diode (LED) or by employing nanocrystals (NCs) of the three primary colors (red,...

  4. Text-Alternative Version: CALiPER Report Series 20 on LED PAR38 Lamps

    Broader source: Energy.gov [DOE]

    Michael Royer, Lighting Engineer, Pacific Northwest National Laboratory: The CALiPER program looks at typical LED lamp performance attributes. As we've gone through the progression of reports, we...

  5. DOE Publishes CALiPER Snapshot Report on LED MR16 Lamps

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy's CALiPER program has released a Snapshot Report on MR16 lamps, which utilizes the LED Lighting Facts® program's extensive product database to help industry...

  6. Dimming LEDs with Phase-Cut Dimmers: The Specifier's Process for Maximizing Success

    SciTech Connect (OSTI)

    Miller, Naomi J.; Poplawski, Michael E.

    2013-10-01T23:59:59.000Z

    This report reviews how phase-cut dimmers work, how LEDs differ from the incandescent lamps that the dimmers were historically designed to control, and how these differences can lead to complications when trying to dim LEDs. Compatibility between a specific LED source and a specific phase-cut dimmer is often unknown and difficult to assess, and ensuring compatibility adds complexity to the design, specification, bidding, and construction observation phases for new buildings and major remodel projects. To maximize project success, this report provides both general guidance and step-by-step procedures for designing phase-controlled LED dimming on both new and existing projects, as well as real-world examples of how to use those procedures.

  7. DOE Publishes CALiPER Report on LED T8 Lamps

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy's CALiPER program has released an Application Summary Report that focuses on the bare-lamp performance of 31 linear LED lamps intended as an alternative to T8...

  8. Collective Experience: A Database-Fuelled, Inter-Disciplinary Team-Led Learning System

    E-Print Network [OSTI]

    Celi, Leo Anthony G.

    We describe the framework of a data-fuelled, interdisciplinary team-led learning system. The idea is to build models using patients from one's own institution whose features are similar to an index patient as regards an ...

  9. Applied Materials Develops an Advanced Epitaxial Growth System to Bring Down LED Costs

    Broader source: Energy.gov [DOE]

    With the help of DOE funding, Applied Materials has developed an advanced epitaxial growth system for gallium nitride (GaN) LED devices that decreases operating costs, increases internal quantum efficiency, and improves binning yields.

  10. Quality and Performance of LED Flashlights in Kenya: Common End User Preferences and Complaints

    E-Print Network [OSTI]

    Tracy, Jenny

    2010-01-01T23:59:59.000Z

    grid lighting market. The lead acid batteries embedded inrechargeable sealed lead-acid batteries are the most popularlead-acid (SLA) battery, LED flashlights powered by dry cell batteries,

  11. LED Replacement Lamps: Current Performance and the Latest on ENERGY STAR®

    Broader source: Energy.gov [DOE]

    This May 19, 2009 webcast summarized CALiPER's recent benchmark testing of common omnidirectional incandescent lamps (e.g., A-lamps), and provided an update on ENERGY STAR criteria for LED integral...

  12. Text-Alternative Version: LED Lighting in a Performing Arts Building Webinar

    Broader source: Energy.gov [DOE]

     Welcome ladies and gentlemen. I'm Bob Davis with the Pacific Northwest National Laboratory, and I'd like to welcome you to today's webcast titled, LEDs, Can They Perform in a Performing Arts...

  13. EECBG Success Story: Shining Energy-Saving LEDs on Utah Starry...

    Energy Savers [EERE]

    LEDs across 14 rural communities. About 2,500 streetlights will be replaced and could save the town 20% to 50% on electricity bills. Learn more. Addthis Related Articles A...

  14. Digital Architecture for Driving Large LED Arrays with Dynamic Bus Voltage Regulation and Phase Shifted PWM

    E-Print Network [OSTI]

    Emitting Diodes (HB-LEDs) with improved system efficiency and reduced EMI. Key advantages are achieved - This paper introduces a digital architecture suitable for driving a large number of High Brightness Light

  15. Successful Selection of LED Streetlight Luminaires: Optimizing Illumination and Economic Performance

    Broader source: Energy.gov [DOE]

    This March 6, 2013 webcast reviewed the factors involved in successful selection of LED streetlight luminaires. Presenters Eric Haugaard of Cree Lighting and Chad Stalker of Philips Lumileds guided...

  16. Two PPPL-led teams win increased supercomputing time to study...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Two PPPL-led teams win increased supercomputing time to study conditions inside fusion plasmas By John Greenwald January 9, 2014 Tweet Widget Google Plus One Share on Facebook...

  17. Veeco Develops a Tool to Reduce Epitaxy Costs and Increase LED Brightness

    Broader source: Energy.gov [DOE]

    With the help of DOE funding, Veeco is working on reducing epitaxy costs and increasing LED efficiency by developing a physical vapor deposition (PVD) tool for depositing aluminum nitride buffer layers on LED substrates. PVD, also known as "sputtering," is an alternative to metal-organic chemical vapor deposition (MOCVD). PVD is a purely physical process that involves plasma sputter bombardment rather than a chemical reaction at the surface to be coated, as in MOCVD.

  18. Adaptive Traffic-Based Techniques For Live Multimedia Streaming

    E-Print Network [OSTI]

    Adaptive Traffic-Based Techniques For Live Multimedia Streaming Gabriel-Miro Muntean and LiamMiro.Muntean@ucd.ie, Liam.Murphy@ucd.ie Abstract The growing number of multimedia stream transmissions done through the time-sensitive applications and especially the continuity of multimedia streaming. The paper presents

  19. Traffic Light Mapping and Detection Nathaniel Fairfield Chris Urmson

    E-Print Network [OSTI]

    Tomkins, Andrew

    by lines painted on the road, traffic lights indicate precedence at intersections, brake lights show when, are becoming common- place as part of commercial driver-assistance systems. With power steering, power brakes obstructions or false positives such as those induced by the brake lights of other vehicles. Happily, both

  20. Traffic Merging for Energy-Efficient Datacenter Networks

    E-Print Network [OSTI]

    Singh, Suresh

    Traffic Merging for Energy-Efficient Datacenter Networks Alessandro Carrega University of Genoa shown that datacenter net- works typically see loads of between 5% ­ 25% but the energy draw these networks more energy proportional ­ that is, the energy draw scales with the network load. We propose

  1. A Comparison of Unsupervised Learning Techniques for Encrypted Traffic Identification

    E-Print Network [OSTI]

    Zincir-Heywood, Nur

    the performance of five unsupervised clustering algorithms: Basic K-Means, Semi-supervised K-Means, DBSCAN, EM Algorithms, K-Means, DBSCAN, EM, Encrypted Traffic Identification. 1. Introduction An important part perspective we benchmark four unsupervised clustering techniques: basic K-Means, semi-supervised K- Means

  2. Traffic-Aware Video Streaming in Broadband Wireless Networks

    E-Print Network [OSTI]

    Ansari, Nirwan

    Traffic-Aware Video Streaming in Broadband Wireless Networks Ehsan Haghani and Nirwan Ansari Shyam in the Internet. Streaming real-time video in wireless networks is a challenging problem due to the stringent video quality at the end user in wireless networks. Our solution incorporates the characteristics

  3. Decentralized Traffic Management: A Synchronization-Based Intersection Control

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    the autonomous vehicle-agents to cross without stopping, i.e., in order to avoid congestions (delays) and energy by the vehicles while crossing the intersections, and the energy consumption due to the speed variations- portation systems. Autonomous vehicles are today considered as a promising approach to deal with traffic

  4. Computation Availability of Crossbar Systems in a Nonuniform Traffic Environment

    E-Print Network [OSTI]

    Atiquzzaman, Mohammed

    Computation Availability of Crossbar Systems in a Non­uniform Traffic Environment M. Atiquzzaman M Multiprocessor systems can provide higher performance, reliability, and availability than single processor performance and reliability are needed. Most previous studies have considered the performance and reliability/availability

  5. Evaluation of Non-intrusive Traffic Detection Technologies Phase III

    E-Print Network [OSTI]

    Minnesota, University of

    TPF-5(171) Evaluation of Non-intrusive Traffic Detection Technologies Đ Phase III #12 not intrude into pavement for installation. ·! Sensors above, below or to the side of the roadway qualify;Miovision #12;Miovision #12;Laser-based sensors #12;PEEK AxleLight #12;TIRTL #12;TIRTL #12;#12;#12;#12;

  6. AT&T Labs -Research Traffic Matrix Estimation

    E-Print Network [OSTI]

    Roughan, Matthew

    engineering (choosing OSPF weights) Reliability analysis Detecting anomalies Understanding traffic over limited availability ­ like a high zoom snap shot · special equipment needed (O&M expensive even if box to get routing matrices Gives the Routing Matrix A #12;AT&T Labs - Research Example App: reliability

  7. Measuring Bicyclists' Uptake of Traffic-Related Air Pollution

    E-Print Network [OSTI]

    Bertini, Robert L.

    Measuring Bicyclists' Uptake of Traffic-Related Air Pollution Alex Bigazzi PSU Transportation Seminar Feb. 28, 2014 Miguel Figliozzi Jim Pankow Wentai Luo Lorne Isabelle Urban Bicyclists' Pollution Uptake 1 #12;Bicycle & Health Promotion Public Health Exercise CrashesPollution Emissions Exposure/ Dose

  8. A categorical model for traffic incident likelihood estimation

    E-Print Network [OSTI]

    Kuchangi, Shamanth

    2007-04-25T23:59:59.000Z

    In this thesis an incident prediction model is formulated and calibrated. The primary idea of the model developed is to correlate the expected number of crashes on any section of a freeway to a set of traffic stream characteristics, so that a...

  9. Power Efficient Traffic Grooming in Optical WDM Networks

    E-Print Network [OSTI]

    @ncsu.edu Abstract--Power-awareness in networking attracts more at- tention as the trends in the energy consumption the objectives of minimizing the number of lightpaths and electronically routed traffic. Energy consumption has Department of Computer Science North Carolina State University Raleigh, NC 27695-8206 USA Email: rouskas

  10. Estimating Emissions in Latin America: An Alternative to Traffic Models

    E-Print Network [OSTI]

    Richner, Heinz

    Estimating Emissions in Latin America: An Alternative to Traffic Models Margarita Ossés de Eicker; Hans Hurni, Centre for Development and Environment (CDE), University of Bern, Switzerland Emissions allow precise estimations of these emissions but are too expensive for a broad application. A simplifed

  11. 1997 Hui Zhang 1 LIRA: Service Differentiation for Traffic

    E-Print Network [OSTI]

    Zhang, Hui

    1 1997 Hui Zhang 1 Carnegie Mellon LIRA: Service Differentiation for Traffic Aggregates With Large Spatial Granularities Ion Stoica Hui Zhang School of Computer Science Carnegie Mellon University 1997 Hui Simulation experiments l Conclusions and future work #12; 2 1997 Hui Zhang 3 Carnegie Mellon Motivation l

  12. 1997 Hui Zhang 1 LIRA: Service Differentiation for Traffic

    E-Print Network [OSTI]

    Zhang, Hui

    1 1997 Hui Zhang 1 Carnegie Mellon LIRA: Service Differentiation for Traffic Aggregates With Large Spatial Granularities Ion Stoica Hui Zhang School of Computer Science Carnegie Mellon University 1997 Hui Simulation experiments q Conclusions and future work #12;2 1997 Hui Zhang 3 Carnegie Mellon Motivation q

  13. PROOF COPY 004805HFS Molecular motors: a traffic cop within?

    E-Print Network [OSTI]

    Gross, Steven

    PROOF COPY 004805HFS PROOF COPY 004805HFS Molecular motors: a traffic cop within? M. A. Welte1 bidirectional, employing multiple plus- and minus-end directed motors. How cells regulate such transport in time approach to predict how much of transport can be understood just from our knowledge of the motors involved

  14. Impact of retailer's promotional activities on customer traffic

    E-Print Network [OSTI]

    Tasic, Ivan

    2007-09-17T23:59:59.000Z

    effect on store traffic that is comparable with the customer count effect of an average holiday. Some 55 percent of the positive long-run promotional activity effect is felt immediately, and the remaining 45 percent is spread over a five week long period...

  15. A Network-Processor-Based Traffic Splitter for Intrusion Detection

    E-Print Network [OSTI]

    Markatos, Evangelos P.

    1 A Network-Processor-Based Traffic Splitter for Intrusion Detection Ioannis Charitakis, Kostas processor and evaluated its performance using a combination of experimental evaluation and simulation. Our network-level security and protection, Network Processors, Intrusion Detection I. Charitakis and E. P

  16. Signal processor for processing ultrasonic receiver signals

    DOE Patents [OSTI]

    Fasching, George E. (Morgantown, WV)

    1980-01-01T23:59:59.000Z

    A signal processor is provided which uses an analog integrating circuit in conjunction with a set of digital counters controlled by a precision clock for sampling timing to provide an improved presentation of an ultrasonic transmitter/receiver signal. The signal is sampled relative to the transmitter trigger signal timing at precise times, the selected number of samples are integrated and the integrated samples are transferred and held for recording on a strip chart recorder or converted to digital form for storage. By integrating multiple samples taken at precisely the same time with respect to the trigger for the ultrasonic transmitter, random noise, which is contained in the ultrasonic receiver signal, is reduced relative to the desired useful signal.

  17. CALiPER Report 21.3: Cost-Effectiveness of Linear (T8) LED Lamps

    SciTech Connect (OSTI)

    Miller, Naomi J.; Perrin, Tess E.; Royer, Michael P.

    2014-05-27T23:59:59.000Z

    Meeting performance expectations is important for driving adoption of linear LED lamps, but cost-effectiveness may be an overriding factor in many cases. Linear LED lamps cost more initially than fluorescent lamps, but energy and maintenance savings may mean that the life-cycle cost is lower. This report details a series of life-cycle cost simulations that compared a two-lamp troffer using LED lamps (38 W total power draw) or fluorescent lamps (51 W total power draw) over a 10-year study period. Variables included LED system cost ($40, $80, or $120), annual operating hours (2,000 hours or 4,000 hours), LED installation time (15 minutes or 30 minutes), and melded electricity rate ($0.06/kWh, $0.12/kWh, $0.18/kWh, or $0.24/kWh). A full factorial of simulations allows users to interpolate between these values to aid in making rough estimates of economic feasibility for their own projects. In general, while their initial cost premium remains high, linear LED lamps are more likely to be cost-effective when electric utility rates are higher than average and hours of operation are long, and if their installation time is shorter.

  18. Assessment of LED Technology in Ornamental Post-Top Luminaires (Host Site: Sacramento, CA)

    SciTech Connect (OSTI)

    Tuenge, Jason R.

    2011-12-01T23:59:59.000Z

    The DOE Municipal Solid-State Street Lighting Consortium has evaluated four different LED replacements for existing ornamental post-top street lights in Sacramento, California. The project team was composed of the City and its consultant, PNNL (representing the Consortium), and the Sacramento Municipal Utility District. Product selection was finalized in March 2011, yielding one complete luminaire replacement and three lamp-ballast retrofit kits. Computer simulations, field measurements, and laboratory testing were performed to compare the performance and cost-effectiveness of the LED products relative to the existing luminaire with 100 W high-pressure sodium lamp. After it was confirmed the LED products were not equivalent to HPS in terms of initial photopic illumination, the following parameters were scaled proportionally to enable equitable (albeit hypothetical) comparisons: light output, input wattage, and pricing. Four replacement scenarios were considered for each LED product, incorporating new IES guidance for mesopic multipliers and lumen maintenance extrapolation, but life cycle analysis indicated cost effectiveness was also unacceptable. Although LED efficacy and pricing continue to improve, this project serves as a timely and objective notice that LED technology may not be quite ready yet for such applications.

  19. Research on optimization of cooling structure of LED element (The 2nd report)

    SciTech Connect (OSTI)

    Kobayashi, T.; Sakate, Y. [Department of Electronics and Control Engineering, Tsuyama National College of Technology, Okayama (Japan); Hashimoto, R. [Collaborative Research Center, Hiroshima University, Hiroshima (Japan); Takashina, T. [International Industry Academia Collaboration Division, Hiroshima University, Hiroshima (Japan); Kanematsu, H. [Department of Materials Science and Engineering, Suzuka National College of Technology, Mie (Japan); Utsumi, Y. [Laboratory of Advanced Science and Technology for Industry, University of Hyogo, Hyogo (Japan)

    2014-02-20T23:59:59.000Z

    This report shows a design guideline on the parts dimension of LED light bulb for heat transfer. LED light bulb is popular owing to the high efficiency and long life. However, LED element is a point heat source. Therefore, LED light bulb has some problems about heat transfer when it is used for lighting. It sometimes causes deterioration by the raise of local temperature, resulting in lowering of efficiency and shorter life. Thus the thermal analysis focused on the number of element, all parts thickness, length, and radiant heat was studied, as systematic report on the points has not been found. In this report, heat radiation was taken into account in the thermal analysis in addition to natural heat convection. Furthermore the temperature of a heat sink model for LED light bulb was measured with thermocouples and thermo-viewer to verify the calculation. The emissivity of aluminum used for the calculation was 0.4. As the result of analysis, it was found that the maximum temperature was mainly influenced by ring length, ring diameter and disk thickness as a design guideline. Concretely, longer length, larger diameter and thicker disk gave lower temperature of LED element. The temperatures of the best and worst model were around 70 °C and 120 °C respectively in the above condition. The temperatures calculated were consistent with those in experiment.

  20. TRAFFIC AND PARKING REGULATIONS 2013/2014 The following document comprises the University of Stirling's Traffic & Parking

    E-Print Network [OSTI]

    Little, Tony

    of Stirling's Traffic & Parking Regulations and sets out the rules for all individuals bringing a vehicle onto the University's Stirling campus. These rules are referred to as the Regulations in this document and may & display ticket unless they opt to park in a full parking space. 1.10 The University of Stirling is a data

  1. TRAFFIC AND PARKING REGULATIONS 2014/2015 The following document comprises the University of Stirling's Traffic & Parking

    E-Print Network [OSTI]

    Little, Tony

    of Stirling's Traffic & Parking Regulations and sets out the rules for all individuals bringing a vehicle onto the University's Stirling campus. These rules are referred to as the Regulations in this document and may & display ticket unless they opt to park in a full parking space. #12;2 1.9 The University of Stirling

  2. Signal Processing:Fourier Signal Processing:Fourier

    E-Print Network [OSTI]

    Rimon, Elon

    Signal Processing:Fourier #12;Signal Processing:Fourier Fourier methods · Continous signals FS ­ Fourier Series : Periodic FT ­ (Integral) Fourier Transform: Transients (aperiodic) ·Discrete (sampled) signals DFS ­Discrete Fourier Series DFT ­ Discrete Fourier Transform #12;Signal Processing:Fourier #12

  3. Impact of photonic crystals on LED light extraction efficiency: approaches and limits to vertical structure designs

    SciTech Connect (OSTI)

    Matioli, Elison; Weisbuch, Claude

    2010-01-01T23:59:59.000Z

    The enhancement of the extraction efficiency in light emitting diodes (LEDs) through the use of photonic crystals (PhCs) requires a structure design that optimizes the interaction of the guided modes with the PhCs. The main optimization parameters are related to the vertical structure of the LED, such as the thickness of layers, depth of the PhCs, position of the quantum wells as well as the PhC period and fill factor. We review the impact of the vertical design of different approaches of PhC LEDs through a theoretical and experimental standpoint, assessing quantitatively the competing mechanisms that act over each guided mode. Three approaches are described to overcome the main limitation of LEDs with surface PhCs, i.e. the insufficient interaction of low order guided modes with the PhCs. The introduction of an AlGaN confining layer in such structure is shown to be effective in extracting a fraction of the optical energy of low order modes; however, this approach is limited by the growth of the lattice mismatched AlGaN layer on GaN. The second approach, based on thin-film LEDs with PhCs, is limited by the presence of an absorbing reflective metal layer close to the guided modes that plays a major role in the competition between PhC extraction and metal dissipation. Finally, we demonstrate both experimentally and theoretically the superior extraction of the guided light in embedded PhC LEDs due to the higher interaction between all optical modes and the PhCs, which resulted in a close to unity extraction efficiency for this device. The use of high-resolution angle-resolved measurements to experimentally determine the PhC extraction parameters was an essential tool for corroborating the theoretical models and quantifying the competing absorption and extraction mechanisms in LEDs.

  4. A peaks-over-threshold analysis of extreme traffic load effects on bridges Franziska Schmidt, Xiao Yi Zhou, Franois Toutlemonde

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    extreme traffic load or traffic load effect. These are: i. a half-normal curve fitted to the end1 A peaks-over-threshold analysis of extreme traffic load effects on bridges Franziska Schmidt focuses on modeling and estimating tail parameters of bridge traffic load effects by generalized Pareto

  5. City traffic operations planners and managers use traffic simulators known as stochastic microscopic simulators to in-

    E-Print Network [OSTI]

    Entekhabi, Dara

    city center, the new meth- od identified signal plans that lead to a 34 percent reduction in average costly than micromodels, are typically used to evaluate transportation strategies, but these lack, and it outperforms traditional simulation-based optimization methods. The framework is robust to initial points

  6. Demonstration Assessment of Light-Emitting Diode (LED) Parking Lot Lighting in Leavenworth, KS

    SciTech Connect (OSTI)

    Myer, Michael; Kinzey, Bruce R.; Curry, Ku'uipo

    2011-05-06T23:59:59.000Z

    This report describes the process and results of a demonstration of solid-state lighting (SSL) technology in a commercial parking lot lighting application, under the U.S. Department of Energy (DOE) Solid-State Lighting Technology GATEWAY Demonstration Program. The parking lot is for customers and employees of a Walmart Supercenter in Leavenworth, Kansas and this installation represents the first use of the LED Parking Lot Performance Specification developed by the DOE’s Commercial Building Energy Alliance. The application is a parking lot covering more than a half million square feet, lighted primarily by light-emitting diodes (LEDs). Metal halide wall packs were installed along the building facade. This site is new construction, so the installed baseline(s) were hypothetical designs. It was acknowledged early on that deviating from Walmart’s typical design would reduce the illuminance on the site. Walmart primarily uses 1000W pulse-start metal halide (PMH) lamps. In order to provide a comparison between both typical design and a design using conventional luminaires providing a lower illuminance, a 400W PMH design was also considered. As mentioned already, the illuminance would be reduced by shifting from the PMH system to the LED system. The Illuminating Engineering Society of North America (IES) provides recommended minimum illuminance values for parking lots. All designs exceeded the recommended illuminance values in IES RP-20, some by a wider margin than others. Energy savings from installing the LED system compared to the different PMH systems varied. Compared to the 1000W PMH system, the LED system would save 63 percent of the energy. However, this corresponds to a 68 percent reduction in illuminance as well. In comparison to the 400W PMH system, the LED system would save 44 percent of the energy and provide similar minimum illuminance values at the time of relamping. The LED system cost more than either of the PMH systems when comparing initial costs. However, when the life-cycle costs from energy and maintenance were factored into the scenario, the LED system had lower costs at the end of a 10-year analysis period. The LED system had a 6.1 year payback compared to the 1000W PMH system and a 7.5 year payback versus the 400W PMH system. The costs reflect high initial cost for the LED luminaire, plus more luminaires and (subsequently) more poles for the LED system. The other major issue affecting cost effectiveness was that Leavenworth, Kansas has very low electricity costs. The melded rate for this site was $0.056 per kWh for electricity. However, if the national electricity rate of $0.1022/kWh was used the payback would change to between four and five years for the LED system. This demonstration met the GATEWAY requirements of saving energy, matching or improving illumination, and being cost effective. The project also demonstrated that the Commercial Building Energy Alliance (CBEA) specification works in practice. Walmart appreciated having an entire site lighted by LEDs to gain more experience with the technology. Walmart is reviewing the results of the demonstration as they consider their entire real estate portfolio.

  7. Lumen Maintenance and Light Loss Factors: Consequences of Current Design Practices for LED's

    SciTech Connect (OSTI)

    Royer, Michael P.

    2013-09-17T23:59:59.000Z

    Synopsis: Light loss factors are used to help lighting systems meet quantitative design criteria throughout the life of the installation, but they also influence energy use. As the light sources currently being specified continue to evolve, it is necessary to reevaluate the methods used in calculating light loss factors, as well as carefully consider the consequences of different product performance attributes. Because of the unique operating characteristics of LEDs and lack of a comprehensive lifetime rating—as well as the problematic relationship between lifetime and lumen maintenance—determining an appropriate lamp lumen depreciation (LLD) factor for LED products is difficult. As a result, a unique solution has been advocated: when quantity of light is an important design consideration, the IES recommends using an LLD of not greater than 0.70. This method deviates from the typical practice for conventional sources of using the ratio of mean to initial lumen output, and can misrepresent actual performance, increase energy use, and inhibit comparisons between products. This paper discusses the complications related to LLD and LEDs, compares the performance of conventional and LED products, and examines alternatives to a maximum LLD of 0.70 for LEDs.

  8. LEDS Global Partnership in Action: Advancing Climate-Resilient Low Emission Development Around the World (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2013-11-01T23:59:59.000Z

    Many countries around the globe are designing and implementing low emission development strategies (LEDS). These LEDS seek to achieve social, economic, and environmental development goals while reducing long-term greenhouse gas (GHG) emissions and increasing resiliency to climate change impacts. The LEDS Global Partnership (LEDS GP) harnesses the collective knowledge and resources of more than 120 countries and international donor and technical organizations to strengthen climate-resilient low emission development efforts around the world.

  9. LED Light Fixture Project FC1 Director's Conference Room: Life Cycle Cost and Break-even Analysis

    E-Print Network [OSTI]

    Johnston, Daniel

    . A light-emitting diode (LED) is a solid-state lighting source that switches on instantly, is readily

  10. Use Patterns of LED Flashlights in Kenya and a One-Year Cost Analysis of Flashlight Ownership

    E-Print Network [OSTI]

    Tracy, Jennifer

    2010-01-01T23:59:59.000Z

    rechargeable sealed-lead acid (SLA) batteries are alsolead-acid (SLA) battery, LED flashlights powered by dry cell batteries,

  11. Low-Cost Substrates for High-Performance Nanorod Array LEDs

    SciTech Connect (OSTI)

    Sands, Timothy; Stach, Eric; Garcia, Edwin

    2009-04-30T23:59:59.000Z

    The completed project, entitled â??Low-Cost Substrates for High-Performance Nanorod LEDs,â?ť targeted the goal of a phosphor-free nanorod-based white LED with IQE > 50% across the spectrum from 450 nm to 600 nm on metallized silicon substrates. The principal achievements of this project included: â?˘ Demonstration of (In,Ga)N nanopyramid heterostructures by a conventional OMVPE process. â?˘ Verification of complete filtering of threading dislocations to yield dislocation-free pyramidal heterostructures. â?˘ Demonstration of electroluminescence with a peak wavelength of ~600 nm from an (In,Ga)N nanopyramid array LED. â?˘ Development of a reflective ZrN/AlN buffer layer for epitaxial growth of GaN films and GaN nanopyramid arrays on (111)Si.

  12. Development of Advanced Manufacturing Methods for Warm White LEDs for General Lighting

    SciTech Connect (OSTI)

    Deshpande, Anirudha; Kolodin, Boris; Jacob, Cherian; Chowdhury, Ashfaqul; Kuenzler, Glenn; Sater, Karen; Aesram, Danny; Glaettli, Steven; Gallagher, Brian; Langer, Paul; Setlur, Anant; Beers, Bill

    2012-03-31T23:59:59.000Z

    GE Lighting Solutions will develop precise and efficient manufacturing techniques for the “remote phosphor” platform of warm-white LED products. In volume, this will be demonstrated to drive significant materials, labor and capital productivity to achieve a maximum possible 53% reduction in overall cost. In addition, the typical total color variation for these white LEDs in production will be well within the ANSI bins and as low as a 4-step MacAdam ellipse centered on the black body curve. Achievement of both of these objectives will be demonstrated while meeting a performance target of > 75 lm/W for a warm-white LED and a reliability target of <30% lumen drop / <2-step MacAdam ellipse shift, estimated over 50,000 hrs.

  13. Epitaxial Growth of GaN-based LEDs on Simple Sacrificial Substrates

    SciTech Connect (OSTI)

    Ian Ferguson; Chris Summers

    2009-12-31T23:59:59.000Z

    The objective of this project is to produce alternative substrate technologies for GaN-based LEDs by developing an ALD interlayer of Al{sub 2}O{sub 3} on sacrificial substrates such as ZnO and Si. A sacrificial substrate is used for device growth that can easily be removed using a wet chemical etchant leaving only the thin GaN epi-layer. After substrate removal, the GaN LED chip can then be mounted in several different ways to a metal heat sink/reflector and light extraction techniques can then be applied to the chip and compared for performance. Success in this work will lead to high efficiency LED devices with a simple low cost fabrication method and high product yield as stated by DOE goals for its solid state lighting portfolio.

  14. LED-Induced Fluorescence System for Tea Classification and Quality Assessment

    E-Print Network [OSTI]

    Dong, Yongjiang; Mei, Liang; Feng, Chao; Yan, Chunsheng; He, Sailing

    2013-01-01T23:59:59.000Z

    A fluorescence system is developed by using several light emitting diodes (LEDs) with different wavelengths as excitation light sources. The fluorescence detection head consists of multi LED light sources and a multimode fiber for fluorescence collection, where the LEDs and the corresponding filters can be easily chosen to get appropriate excitation wavelengths for different applications. By analyzing fluorescence spectra with the principal component analysis method, the system is utilized in the classification of four types of green tea beverages and two types of black tea beverages. Qualities of the Xihu Longjing tea leaves of different grades, as well as the corresponding liquid tea samples, are studied to further investigate the ability and application of the system in the evaluation of classification/quality of tea and other foods.

  15. Lattice-mismatched GaInP LED devices and methods of fabricating same

    DOE Patents [OSTI]

    Mascarenhas, Angelo; Steiner, Myles A; Bhusal, Lekhnath; Zhang, Yong

    2014-10-21T23:59:59.000Z

    A method (100) of fabricating an LED or the active regions of an LED and an LED (200). The method includes growing, depositing or otherwise providing a bottom cladding layer (208) of a selected semiconductor alloy with an adjusted bandgap provided by intentionally disordering the structure of the cladding layer (208). A first active layer (202) may be grown above the bottom cladding layer (208) wherein the first active layer (202) is fabricated of the same semiconductor alloy, with however, a partially ordered structure. The first active layer (202) will also be fabricated to include a selected n or p type doping. The method further includes growing a second active layer (204) above the first active layer (202) where the second active layer (204) Is fabricated from the same semiconductor alloy.

  16. Signal sciences workshop proceedings

    SciTech Connect (OSTI)

    Candy, J.V.

    1997-05-01T23:59:59.000Z

    This meeting is aimed primarily at signal processing and controls. The technical program for the 1997 Workshop includes a variety of efforts in the Signal Sciences with applications in the Microtechnology Area a new program at LLNL and a future area of application for both Signal/Image Sciences. Special sessions organized by various individuals in Seismic and Optical Signal Processing as well as Micro-Impulse Radar Processing highlight the program, while the speakers at the Signal Processing Applications session discuss various applications of signal processing/control to real world problems. For the more theoretical, a session on Signal Processing Algorithms was organized as well as for the more pragmatic, featuring a session on Real-Time Signal Processing.

  17. Atypical Behavior Identification in Large Scale Network Traffic

    SciTech Connect (OSTI)

    Best, Daniel M.; Hafen, Ryan P.; Olsen, Bryan K.; Pike, William A.

    2011-10-23T23:59:59.000Z

    Cyber analysts are faced with the daunting challenge of identifying exploits and threats within potentially billions of daily records of network traffic. Enterprise-wide cyber traffic involves hundreds of millions of distinct IP addresses and results in data sets ranging from terabytes to petabytes of raw data. Creating behavioral models and identifying trends based on those models requires data intensive architectures and techniques that can scale as data volume increases. Analysts need scalable visualization methods that foster interactive exploration of data and enable identification of behavioral anomalies. Developers must carefully consider application design, storage, processing, and display to provide usability and interactivity with large-scale data. We present an application that highlights atypical behavior in enterprise network flow records. This is accomplished by utilizing data intensive architectures to store the data, aggregation techniques to optimize data access, statistical techniques to characterize behavior, and a visual analytic environment to render the behavioral trends, highlight atypical activity, and allow for exploration.

  18. Robust Background Subtraction with Foreground Validation for Urban Traffic Video

    SciTech Connect (OSTI)

    Cheung, S S; Kamath, C

    2004-01-15T23:59:59.000Z

    Identifying moving objects in a video sequence is a fundamental and critical task in many computer-vision applications. Background subtraction techniques are commonly used to separate foreground moving objects from the background. Most background subtraction techniques assume a single rate of adaptation, which is inadequate for complex scenes such as a traffic intersection where objects are moving at different and varying speeds. In this paper, we propose a foreground validation algorithm that first builds a foreground mask using a slow-adapting Kalman filter, and then validates individual foreground pixels by a simple moving object model, built using both the foreground and background statistics as well as the frame difference. Ground-truth experiments with urban traffic sequences show that our proposed algorithm significantly improves upon results using only Kalman filter or frame-differencing, and outperforms other techniques based on mixture of Gaussians, median filter, and approximated media filter.

  19. Hamiltonian traffic dynamics in microfluidic-loop networks

    E-Print Network [OSTI]

    Raphaël Jeanneret; Julien Piera-Vest; Denis Bartolo

    2011-09-28T23:59:59.000Z

    Recent microfluidic experiments revealed that large particles advected in a fluidic loop display long-range hydrodynamic interactions. However, the consequences of such couplings on the traffic dynamics in more complex networks remain poorly understood. In this letter, we focus on the transport of a finite number of particles in one-dimensional loop networks. By combining numerical, theoretical, and experimental efforts, we evidence that this collective process offers a unique example of Hamiltonian dynamics for hydrodynamically interacting particles. In addition, we show that the asymptotic trajectories are necessarily reciprocal despite the microscopic traffic rules explicitly break the time reversal symmetry. We exploit these two remarkable properties to account for the salient features of the effective three-particle interaction induced by the exploration of fluidic loops.

  20. Demonstration of LED Retrofit Lamps at the Smithsonian American Art Museum, Washington, DC

    SciTech Connect (OSTI)

    Miller, Naomi J.; Rosenfeld, Scott M.

    2012-06-22T23:59:59.000Z

    This report documents observations and results obtained from a lighting demonstration project conducted under the U.S. Department of Energy GATEWAY Solid-State Lighting (SSL) Technology Demonstration Program at the Smithsonain American Art Museum in Washington, DC. LED Lamp samples were tested in the museum workshop, temporarily installed in a gallery for feedback, and ultimately replaced all traditional incandescent lamps in one gallery of modernist art at the American Art Museum and partially replacing lamps in two galleries at the Musesum's Renwick Gallery. This report describes the selection and testing process, technology challenges, perceptions, economics, energy use, and mixed results of usign LED replacement lamps in art galleries housing national treasures.

  1. High-Efficiency Non-Polar GaN-Based LEDs

    SciTech Connect (OSTI)

    Paul Fini

    2010-11-30T23:59:59.000Z

    Inlustra Technologies with subcontractor U.C. Santa Barbara conducted a project with the principle goal of demonstrating high internal quantum efficiency blue (430 nm) and green (540nm) light emitting diodes (LEDs) on low-defect density non-polar GaN wafers. Inlustra pursued the fabrication of smooth thick a-plane and m-plane GaN films, as well as defect reduction techniques such as lateral epitaxial overgrowth (LEO) to uniformly lower dislocation density in these films. Limited free-standing wafers were produced as well. By the end of the reporting period, Inlustra had met its milestone of dislocation reduction to < 5 x 10{sup 6} cm{sup -2}. Stacking faults were still present in appreciable density ({approx} 1 x 10{sup 5} cm{sup -1}), but were not the primary focus of defect reduction since there have been no published studies establishing their detrimental effects on LED performance. Inlustra's LEO progress built a solid foundation upon which further commercial development of GaN substrates will occur. UCSB encountered multiple delays in its LED growth and fabrication efforts due to unavoidable facilities outages imposed by ongoing construction in an area adjacent to the metalorganic chemical vapor deposition (MOCVD) laboratory. This, combined with the large amount of ab initio optimization required for the MOCVD system used during the project, resulted in unsatisfactory LED progress. Although numerous blue-green photoluminescence results were obtained, only a few LED structures exhibited electroluminescence at appreciable levels. UCSB also conducting extensive modeling (led by Prof. Van de Walle) on the problem of non-radiative Auger recombination in GaN-based LED structures, which has been posited to contribute to LED efficiency 'droop' at elevated current density. Unlike previous modeling efforts, UCSB's approach was truly a first-principles ab initio methodology. Building on solid numerical foundations, the Auger recombination rates of In{sub x}Ga{sub 1-x}N alloys were calculated from first-principles density-functional and many-body-perturbation theory. The differing mechanisms of inter- and intra-band recombination were found to affect different parts of the emission spectrum. In the blue to green spectral region and at room temperature the Auger coefficient was calculated to be as large as 2 x 10{sup -30} cm{sup 6} s{sup -1}; in the infrared it is even larger. These results indicated that Auger recombination may be responsible for the loss of quantum efficiency that affects InGaN-based light emitters, whether on non-polar or polar crystal planes.

  2. LEDS-An overview of the state of the art in technology and application

    SciTech Connect (OSTI)

    Johnson, Stephen

    2002-03-01T23:59:59.000Z

    Solid state lighting in the form of Light Emitting Diodes (LEDs) is bringing new sources with different operating characteristics to the market. With the control in dimension, optics, intensity and color, these sources have the potential to transform the way we use light. This paper will review the recent improvements in performance that have been achieved by these devices, focusing on those product attributes identified as being critical to end users. The paper will conclude with a consideration of applications capitalizing on the LEDs' unique operating and physical properties.

  3. On freeway traffic control by a lane closure

    E-Print Network [OSTI]

    Henderson, Donald Manson

    1971-01-01T23:59:59.000Z

    ON PREENAY TRAPPIC CONTROL BY. A LANE CLOSURE A Thesis by DONALD MANSON HENDERSON Submitted to the. Graduate College of Texas A&M University in partial fulfillment of the requirement. for the degree of MASTER OP SCIENCE Ma)or Suh]ect: Civil... Engineering August 1971 ON FREEWAY TRAFFIC CONTROL BY A LANE CLOSURE A Thesis by DONALD MANSON HENDERSON Approved as to style and content by: (Chairman of ommittee) (Head of Departmen (Member) (Member) (Member) ember) (Member) August 1971 ABSTRACT...

  4. Traffic Dynamics Prospectives: From Fundamental Diagram to Energy Balance

    E-Print Network [OSTI]

    Bertini, Robert L.

    Traffic Dynamics Prospectives: From Fundamental Diagram to Energy Balance R. Mahnke1 , Ch. Liebe, R) = vmax D m 2 - arctan xi D (13) Energy balance: d dt (Ekin(vi) + Epot(xi)) + i(xi, vi, vi+1) = 0 (14) with i as energy flux. 08.07.2008 Woods Hole ­ p.8/11 #12;Energy Balance with Energy Flux Energy balance

  5. Taxiway Aircraft Traffic Scheduling: A Model and Solution Algorithms

    E-Print Network [OSTI]

    Tian, Chunyu

    2012-10-19T23:59:59.000Z

    -known of these policies are the Ground Delay Progr am and Collaborative Decision Making (CDM). 15 The Ground Delay Program is currently implemented by the Federal Aviation Administration (FAA) to control air traffic when the acceptance rate of the destination... directions, they are referred as intersecting runways. In runway operations, the most important factors that need to be considered include wake vortex separations. Federal Aviation Administration categorizes the aircraft into three classes according...

  6. A Learning System for Discriminating Variants of Malicious Network Traffic

    SciTech Connect (OSTI)

    Beaver, Justin M [ORNL; Symons, Christopher T [ORNL; Gillen, Rob [ORNL

    2013-01-01T23:59:59.000Z

    Modern computer network defense systems rely primarily on signature-based intrusion detection tools, which generate alerts when patterns that are pre-determined to be malicious are encountered in network data streams. Signatures are created reactively, and only after in-depth manual analysis of a network intrusion. There is little ability for signature-based detectors to identify intrusions that are new or even variants of an existing attack, and little ability to adapt the detectors to the patterns unique to a network environment. Due to these limitations, the need exists for network intrusion detection techniques that can more comprehensively address both known unknown networkbased attacks and can be optimized for the target environment. This work describes a system that leverages machine learning to provide a network intrusion detection capability that analyzes behaviors in channels of communication between individual computers. Using examples of malicious and non-malicious traffic in the target environment, the system can be trained to discriminate between traffic types. The machine learning provides insight that would be difficult for a human to explicitly code as a signature because it evaluates many interdependent metrics simultaneously. With this approach, zero day detection is possible by focusing on similarity to known traffic types rather than mining for specific bit patterns or conditions. This also reduces the burden on organizations to account for all possible attack variant combinations through signatures. The approach is presented along with results from a third-party evaluation of its performance.

  7. Continuous kinematic wave models of merging traffic flow

    E-Print Network [OSTI]

    Wen-Long Jin

    2010-04-13T23:59:59.000Z

    Merging junctions are important network bottlenecks, and a better understanding of merging traffic dynamics has both theoretical and practical implications. In this paper, we present continuous kinematic wave models of merging traffic flow which are consistent with discrete Cell Transmission Models with various distribution schemes. In particular, we develop a systematic approach to constructing kinematic wave solutions to the Riemann problem of merging traffic flow in supply-demand space. In the new framework, Riemann solutions on a link consist of an interior state and a stationary state, subject to admissible conditions such that there are no positive and negative kinematic waves on the upstream and downstream links respectively. In addition, various distribution schemes in Cell Transmission Models are considered entropy conditions. In the proposed analytical framework, we prove that the stationary states and boundary fluxes exist and are unique for the Riemann problem for both fair and constant distribution schemes. We also discuss two types of invariant merge models, in which local and discrete boundary fluxes are the same as global and continuous ones. With numerical examples, we demonstrate the validity of the analytical solutions of interior states, stationary states, and corresponding kinematic waves. Discussions and future studies are presented in the conclusion section.

  8. Chip-Scale Power Conversion for LED Lighting: Integrated Power Chip Converter for Solid-State Lighting

    SciTech Connect (OSTI)

    None

    2010-10-01T23:59:59.000Z

    ADEPT Project: Teledyne is developing cost-effective power drivers for energy-efficient LED lights that fit on a compact chip. These power drivers are important because they transmit power throughout the LED device. Traditional LED driver components waste energy and don't last as long as the LED itself. They are also large and bulky, so they must be assembled onto a circuit board separately which increases the overall manufacturing cost of the LED light. Teledyne is shrinking the size and improving the efficiency of its LED driver components by using thin layers of an iron magnetic alloy and new gallium nitride on silicon devices. Smaller, more efficient components will enable the drivers to be integrated on a single chip, reducing costs. The new semiconductors in Teledyne's drivers can also handle higher levels of power and last longer without sacrificing efficiency. Initial applications for Teledyne's LED power drivers include refrigerated grocery display cases and retail lighting.

  9. Asia-Pacific Trade Economists' Conference Trade-Led Growth in Times of Crisis

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Asia-Pacific Trade Economists' Conference Trade-Led Growth in Times of Crisis The World Trade session 2: The Crisis: A Catalyst for More Coherent Trade Policies and Inclusive Growth? Author: Patrick A or carrying the endorsement of the United Nations. #12;1 Policy Brief October 26, 2009 The World Trade Regime

  10. 1 Introduction The development of wind energy use has led to

    E-Print Network [OSTI]

    Heinemann, Detlev

    1 Introduction The development of wind energy use has led to a noticeable contribution in of electricity by wind energy acts as a negative load leading to an increase in fluctuations of net load patterns conventional reserves have to be kept ready to replace the wind energy share in case of decreasing wind speeds

  11. Depth of cure and compressive strength of dental composites cured with blue light emitting diodes (LEDs)

    E-Print Network [OSTI]

    Ashworth, Stephen H.

    Depth of cure and compressive strength of dental composites cured with blue light emitting diodes with either a light emitting diode (LED) based light curing unit (LCU) or a conventional halogen LCU do reserved. Keywords: Blue light emitting diodes; Light curing unit; Composites; Irradiance; Spectrum; Depth

  12. Coupled optical and electronic simulations of electrically pumped photonic-crystal-based LEDs

    E-Print Network [OSTI]

    Dutton, Robert W.

    to investigate design tradeoffs in electrically pumped photonic crystal light emitting diodes. A finite. Keywords: Photonic crystal light emitting diode, electrically pumped device 1. INTRODUCTION Recently optoelectronic devices, such as light emitting diodes (LEDs) and lasers. It has been suggested that a thin slab

  13. Ruofan Wu, Hieu Pham Trung Nguyen and Zetian Mi INTRODUCTION TO LEDs

    E-Print Network [OSTI]

    Barthelat, Francois

    -in-a-Wire Light Emitting Diodes and Prevention Method Nano-electronic Devices and Materials, Electrical Computer., Efficiency droop in nitride-based light-emitting diodes. Physica Status Solidi a-Applications and Materials history. Nature Photonics 2007, 1 (4), 189-192. [4] Holonyak, N., Is the light emitting diode (LED

  14. DOE Publishes CALiPER Report on Linear (T8) LED Lamps in Recessed Troffers

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy's CALiPER program has released Report 21.2, which is part of a series of investigations on linear LED lamps. Report 21.2 focuses on the performance of three linear (T8...

  15. DOE Publishes CALiPER Report on Cost-Effectiveness of Linear (T8) LED Lamps

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy's CALiPER program has released Report 21.3, which is part of a series of investigations on linear LED lamps. Report 21.3 details a set of life-cycle cost simulations...

  16. What led to the pervasiveness of hybrids between Cx. pipiens and Cx. molestus in

    E-Print Network [OSTI]

    What led to the pervasiveness of hybrids between Cx. pipiens and Cx. molestus in North America populations with a few hybrid individuals, as well as populations with pure Cx. pipiens signatures and populations with a mix of pure Cx. pipiens and pure Cx. molestus signatures (Fig. 2). Indeed, previous

  17. forestry.gov.uk/carboncode The Woodland Carbon Code is an initiative led by the

    E-Print Network [OSTI]

    carbon from these projects brings many benefits in addition to carbon sequestration. is effectivelyforestry.gov.uk/carboncode ® The Woodland Carbon Code is an initiative led by the Forestry Commission and supported by a Carbon Advisory Group of UK forest industry and carbon market experts. A buyers

  18. Office of International Programs Education Abroad CSU Faculty-Led Programs Support

    E-Print Network [OSTI]

    Office of International Programs ­ Education Abroad 12/2012 CSU Faculty-Led Programs Support Below describes the levels of support and ways that the Office of International Programs ­ Education Abroad unit in the field of international education Application and Maintain website and online application system

  19. High-power LEDs based on InGaAsP/InP heterostructures

    SciTech Connect (OSTI)

    Rakovics, V. [Hungarian Academy of Sciences, Institute of Technical Physics and Materials Science, Research Centre for Natural Sciences (Hungary); Imenkov, A. N.; Sherstnev, V. V.; Serebrennikova, O. Yu.; Il’inskaya, N. D.; Yakovlev, Yu. P., E-mail: Yak@iropt1.ioffe.ru [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)

    2014-12-15T23:59:59.000Z

    High-power light-emitting diodes (LEDs) with mesa diameters of 100, 200, and 300 ?m are developed on the basis of InGaAsP/InP heterostructures. The mesas are close in shape to a truncated cone with a generatrix inclination angle of ?45° in the vicinity of the active region of the LED, with a ring etched around the mesa serving as a reflector. The emission spectra and directivity patterns of these LEDs are studied in a wide range of current densities and it is shown that radiative recombination is dominant to a current density of ?5000 A/cm{sup 2}, which makes these structures promising for the development of high-power LEDs. An emission power of ?14 mW is obtained in the continuous-wave mode (I = 0.2 A, ? = 1.1 ?m), and that of 77 mW, in the pulsed mode (I = 2 A, ? = 1.1 ?m), which corresponds to external quantum efficiencies of 6.2 and 3.4%, respectively.

  20. General practitioner-led commissioning in the NHS: progress, prospects and pitfalls

    E-Print Network [OSTI]

    Birmingham, University of

    General practitioner-led commissioning in the NHS: progress, prospects and pitfalls Russell Mannion of general practitioner (GP) consortia. These organisations will have responsibility for commissioning on impact of the previous models of GP commissioning that have been introduced in the NHS with the aim

  1. Calibration of Cangaroo II Telescope Using a Fast Blue LED Light Flasher

    E-Print Network [OSTI]

    Enomoto, Ryoji

    , as well as test the data acquisition electronics. Our technique is an independent variation of the laser , and a risetime of #24; 1 ns. The LED has a double emitter giving a non-uniform light pool. By drilling a small

  2. Philips' LED Luminaires Brighten the Rensselaer Engineering Fabrication & Prototyping Facility (also known as the Machine Shop)

    E-Print Network [OSTI]

    Linhardt, Robert J.

    . #12;To help bridge its research efforts with currently available solid state lighting technology outreach to increase campus and community awareness as to the benefits of solid state lighting. About Royal a donation of LED fixtures from Philips Lighting. The Smart Lighting Sustainability Club, comprised

  3. December 2014 CCE-Led One-Time Service Projects Transportation Provided

    E-Print Network [OSTI]

    Collins, Gary S.

    December 2014 CCE-Led One-Time Service Projects Transportation Provided Check In Times Listed Place Senior Center Manicures 6 PM ­ 8 PM 4 Colton Pen Friends 8:15 AM ­ 11:30 AM Recycling Outreach Friends 8:15 AM ­ 11:30 AM Recycling Outreach Campus to Community 10 AM ­ 1 PM Whitman Senior Living

  4. Mercury Releases to Air and Rivers Contaminate Ocean Fish: Dartmouth-Led Effort Publishes Major Findings

    E-Print Network [OSTI]

    Myers, Lawrence C.

    Mercury Releases to Air and Rivers Contaminate Ocean Fish: Dartmouth-Led Effort Publishes Major and in Sources to Seafood: Mercury Pollution in the Marine Environment-- a companion report by the Dartmouth released into the air and then deposited into oceans, contaminates seafood commonly eaten by people

  5. Crystal coat warms up LED light 16:46 01 February 2008

    E-Print Network [OSTI]

    Demir, Hilmi Volkan

    in the commercial market. Illuminating buildings accounts for about a quarter of the electricity used in the US in the home. Now researchers have used nanocrystals to create LEDs that give off a warm white light. Fine Articles 'Smart' lamp offers true mood lighting http://technology.newscientist.com/article/mg19626276

  6. Phosphors for near UV-Emitting LED's for Efficacious Generation of White Light

    SciTech Connect (OSTI)

    McKittrick, Joanna

    2013-09-30T23:59:59.000Z

    1) We studied phosphors for near-UV (nUV) LED application as an alternative to blue LEDs currently being used in SSL systems. We have shown that nUV light sources could be very efficient at high current and will have significantly less binning at both the chip and phosphor levels. We identified phosphor blends that could yield 4100K lamps with a CRI of approximately 80 and LPWnUV,opt equal to 179 for the best performing phosphor blend. Considering the fact that the lamps were not optimized for light coupling, the results are quite impressive. The main bottleneck is an optimum blue phosphor with a peak near 440 nm with a full width half maximum of about 25 nm and a quantum efficiency of >95%. Unfortunately, that may be a very difficult task when we want to excite a phosphor at ~400 nm with a very small margin for Stokes shift. Another way is to have all the phosphors in the blend having the excitation peak at 400 nm or slightly shorter wavelength. This could lead to a white light source with no body color and optimum efficacy due to no self-absorption effects by phosphors in the blend. This is even harder than finding an ideal blue phosphor, but not necessarily impossible. 2) With the phosphor blends identified, light sources using nUV LEDs at high current could be designed with comparable efficacy to those using blue LEDs. It will allow us to design light sources with multiple wattages using the same chips and phosphor blends simply by varying the input current. In the case of blue LEDs, this is not currently possible because varying the current will lower the efficacy at high current and alter the color point. With improvement of phosphor blends, control over CRI could improve. Less binning at the chip level and also at the phosphor blend level could reduce the cost of SSL light sources. 3) This study provided a deeper understanding of phosphor characteristics needed for LEDs in general and nUV LEDs in particular. Two students received Ph.D. degrees and three undergraduates participated in this work. Two of the undergraduate students are now in graduate school. The results were widely disseminated – 20 archival journal publications (published, accepted or in preparation) and three conference proceedings resulted. The students presented their work at 11 different national/international conferences (32 oral or poster presentations) and the PI’s delivered 12 invited, keynote or plenary lectures.

  7. Trade-offs in signalling components differ with signalling effort

    E-Print Network [OSTI]

    Bertram, Sue

    ARTICLES Trade-offs in signalling components differ with signalling effort SUSAN M. BERTRAM on signal components, males that signal often might be forced to make trade-offs among these signalling limitations. We explored the conditions under which males make trade-offs among components of signalling

  8. The Dynamics of Internet Traffic: Self-Similarity, Self-Organization, and Complex Phenomena

    E-Print Network [OSTI]

    Reginald D. Smith

    2010-09-05T23:59:59.000Z

    The Internet is the most complex system ever created in human history. Therefore, its dynamics and traffic unsurprisingly take on a rich variety of complex dynamics, self-organization, and other phenomena that have been researched for years. This paper is a review of the complex dynamics of Internet traffic. Departing from normal treatises, we will take a view from both the network engineering and physics perspectives showing the strengths and weaknesses as well as insights of both. In addition, many less covered phenomena such as traffic oscillations, large-scale effects of worm traffic, and comparisons of the Internet and biological models will be covered.

  9. E-Print Network 3.0 - air traffic management Sample Search Results

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Sridhar and Kapil... of the problems in Traffic Flow ... Source: NASA - Center-TRACTION Automation System (CTAS) Collection: Energy Storage, Conversion and Utilization 2 Table of...

  10. The Elusive “Life” of LEDs: How TM-21 Contributes to the Solution

    SciTech Connect (OSTI)

    Richman, Eric E.

    2011-11-18T23:59:59.000Z

    This magazine article discusses the issue of LED 'lifetime' and explains where TM-21 plays as part of the solution to this issue. In August 2011, the Illuminating Engineering Society (IES) published the TM-21 document entitled 'Lumen degradation lifetime estimation method for LED light sources.' TM-21 is the IES-recommended method for projecting lumen degradation of an LED package, array or module based on data collected according to LM-80. The lighting community expects TM-21 to become the standard method for projecting useful LED lighting product life at realistic operating temperature. This article presents the development process behind TM-21, and clarifies how and when to apply the lifetime extrapolation method to arrive at reasonable and useful estimations. Why TM-21 and why now? We are all familiar with the very real but sometimes exaggerated long-life attributes of LED technology. Not the least of these is the potential for very long life that helps make it an attractive design choice. The trick has been and continues to be how to measure or estimate this longevity to provide assurance to users of this technology's reliability (life) compared to other options. We also understand that the overall reliability of a complete LED lighting fixture can be affected by the reliability of individual product components (driver, lens, etc.) and should be accounted for in lifetime estimations. The useful life of standard lighting technologies is defined as the time to filament or cathode failure. For most of these lamps, the time period prior to failure exhibits acceptable levels of light output, as shown with the solid lines in Fig. 1. This makes it easy to determine when to replace the lamp. However, LEDs do not have filament burn-out that conveniently announces the end of life (dashed line in Fig. 1). Further, the rapid development of the technology and the desire to bring products to market in a timely manner does not allow for actual testing verification of the long lives claimed (100,000 or even 35,000 hours). As a result, the industry has come to accept a definition of the end of the useful life of an LED as the point when it no longer provides a specified level of light output. And finally, the life and performance of LED lighting products depends greatly on excess heat retained at the diode. This is why LEDs require testing at multiple temperatures such that when a source is installed in a luminaire, its actual operating temperature can be measured and lumen depreciation of the product can be derived. Therefore, to serve the solid-state lighting industry, the Technical Procedures Committee (TPC) of the IES proceeded to develop appropriate tests for use in rating LED product longevity. The initial need was a measure of the basic lumen degradation of LED source components identified by a module, package, or array of diodes and this came in the form of LM-80. Importantly, LM-80 only specifies how to measure lumen depreciation to a minimum of 6000 hours (but recommends testing to 10,000 hours or longer). LM-80 stops short of using that data to estimate any depreciation after that, which is where TM-21 comes in. The TM-21 working group (WG) as part of the IES TPC was formed to develop the lumen depreciation projection method and spent over three years exploring many options. The WG evaluated various projection options starting with an analysis of various mathematical, engineering-based models to provide effective depreciation fit and a useful projection method. Next, the WG analyzed LED lumen maintenance behavior using over 40 sets of LM-80-08 test data (20 sets with 10,000 hours or more) collected from four major LED manufacturers. The working group also examined the accuracy of proposed projections using various proposed models and LM-80 data that extended up to 15,000 hours.

  11. High-Power Warm-White Hybrid LED Package for Illumination

    SciTech Connect (OSTI)

    Soer, Wouter

    2013-09-19T23:59:59.000Z

    In this project, an integrated warm-white hybrid light engine was developed. The hybrid approach involves combining phosphor-converted off-white InGaN LEDs and direct-emitting red AlInGaP LEDs in a single light engine to achieve high efficacy together with high color rendering index. We developed and integrated technology improvements in InGaN and AlInGaP die technology, phosphor technology, package architecture and encapsulation, to realize a hybrid warm-white LED package with an efficacy of 140 lm/W at a correlated color temperature of 3000K and a color rendering index of 90, measured under representative operating conditions. This efficacy is 26% higher than the best warm-white LEDs of similar specification that are commercially available at the end of the project. Since the InGaN- and AlInGaP-based LEDs used in the hybrid engine show different behavior as a function of current and temperature, a control system needs to be in place to ensure a stable color point over all operating conditions. In this project, we developed an electronic control circuit that is fully integrated into the light engine in such a way that the module can simply be driven by a conventional single-channel driver. The integrated control circuit uses a switch-mode boost converter topology to control the LED drive currents based on the temperature and the input current of the light engine. A color control performance of 5 SDCM was demonstrated, and improvement to 3 SDCM is considered well within reach. The combination of high efficacy and ease of integration with existing single-channel drivers is expected to facilitate the adoption of the hybrid technology and accelerate the energy savings associated with solid-state lighting. In the product commercialization plan, downlights and indirect-lit troffers have been selected as the first target applications for this product concept. Fully functional integrated prototypes have been developed for both applications, and the business case evaluation is ongoing as of the end of the project.

  12. Universal signal processing method for multimode reflective sensors

    E-Print Network [OSTI]

    Larson, Robert Eugene

    1988-01-01T23:59:59.000Z

    sensitivity, but the sensor configuration is complicated and requires the use of expensive lasers and single mode fibers. Amplitude modulation trades sensitivity for low cost and ease of configuration by using light emitting diodes and multimode fibers. A... method for reflective sensors using optical fibers as the data transmission media. The proposed transmitter - receiver unit was based on the amplitude modulation of reflected optical signals. This involves the use of an light emitting diode (LED...

  13. Advanced method for increasing the efficiency of white light quantum dot LEDs

    SciTech Connect (OSTI)

    Duty, Chad E [ORNL; Bennett, Charlee J C [ORNL; Sabau, Adrian S [ORNL; Jellison Jr, Gerald Earle [ORNL; Boudreaux, Philip R [ORNL; Walker, Steven C [ORNL; Ott, Ronald D [ORNL

    2011-01-01T23:59:59.000Z

    Covering a light-emitting diode (LED) with quantum dots (QDs) can produce a broad spectrum of white light. However, current techniques for applying QDs to LEDs suffer from a high density of defects and a non-uniform distribution of QDs, which, respectively, diminish the efficiency and quality of emitted light. Oak Ridge National Laboratory (ORNL) has the unique capability to thermally anneal QD structures at extremely high power densities for very short durations. This process, called pulse thermal processing (PTP), reduces the number of point defects while maintaining the size and shape of the original QD nanostructure. Therefore, the efficiency of the QD wavelength conversion layer is improved without altering the emission spectrum defined by the size distribution of theQD nanoparticles. The current research uses a thermal model to predict annealing temperatures during PTP and demonstrates up to a 300% increase in photoluminescence for QDs on passive substrates.

  14. Development of Advanced LED Phosphors by Spray-based Processes for Solid State Lighting

    SciTech Connect (OSTI)

    Cabot Corporation

    2007-09-30T23:59:59.000Z

    The overarching goal of the project was to develop luminescent materials using aerosol processes for making improved LED devices for solid state lighting. In essence this means improving white light emitting phosphor based LEDs by improvement of the phosphor and phosphor layer. The structure of these types of light sources, displayed in Figure 1, comprises of a blue or UV LED under a phosphor layer that converts the blue or UV light to a broad visible (white) light. Traditionally, this is done with a blue emitting diode combined with a blue absorbing, broadly yellow emitting phosphor such as Y{sub 3}Al{sub 5}O{sub 12}:Ce (YAG). A similar result may be achieved by combining a UV emitting diode and at least three different UV absorbing phosphors: red, green, and blue emitting. These emitted colors mix to make white light. The efficiency of these LEDs is based on the combined efficiency of the LED, phosphor, and the interaction between the two. The Cabot SSL project attempted to improve the over all efficiency of the LED light source be improving the efficiency of the phosphor and the interaction between the LED light and the phosphor. Cabot's spray based process for producing phosphor powders is able to improve the brightness of the powder itself by increasing the activator (the species that emits the light) concentration without adverse quenching effects compared to conventional synthesis. This will allow less phosphor powder to be used, and will decrease the cost of the light source; thus lowering the barrier of entry to the lighting market. Cabot's process also allows for chemical flexibility of the phosphor particles, which may result in tunable emission spectra and so light sources with improved color rendering. Another benefit of Cabot's process is the resulting spherical morphology of the particles. Less light scattering results when spherical particles are used in the phosphor layer (Figure 1) compared to when conventional, irregular shaped phosphor particles are used. This spherical morphology will result in better light extraction and so an improvement of efficiency in the overall device. Cabot is a 2.5 billion dollar company that makes specialized materials using propriety spray based technologies. It is a core competency of Cabot's to exploit the spray based technology and resulting material/morphology advantages. Once a business opportunity is clearly identified, Cabot is positioned to increase the scale of the production to meet opportunity's need. Cabot has demonstrated the capability to make spherical morphology micron-sized phosphor powders by spray based routes for PDP and CRT applications, but the value proposition is still unproven for LED applications. Cabot believes that the improvements in phosphor powders yielded by their process will result in a commercial advantage over existing technologies. Through the SSL project, Cabot has produced a number of different compositions in a spherical morphology that may be useful for solid state lights, as well as demonstrated processes that are able to produce particles from 10 nanometers to 3 micrometers. Towards the end of the project we demonstrated that our process produces YAG:Ce powder that has both higher internal quantum efficiency (0.6 compared to 0.45) and external quantum efficiency (0.85 compared to 0.6) than the commercial standard (see section 3.4.4.3). We, however, only produced these highly bright materials in research and development quantities, and were never able to produce high quantum efficiency materials in a reproducible manner at a commercial scale.

  15. LED lamp or bulb with remote phosphor and diffuser configuration with enhanced scattering properties

    DOE Patents [OSTI]

    Tong, Tao; Le Toquin, Ronan; Keller, Bernd; Tarsa, Eric; Youmans, Mark; Lowes, Theodore; Medendorp, Jr., Nicholas W; Van De Ven, Antony; Negley, Gerald

    2014-11-11T23:59:59.000Z

    An LED lamp or bulb is disclosed that comprises a light source, a heat sink structure and an optical cavity. The optical cavity comprises a phosphor carrier having a conversions material and arranged over an opening to the cavity. The phosphor carrier comprises a thermally conductive transparent material and is thermally coupled to the heat sink structure. An LED based light source is mounted in the optical cavity remote to the phosphor carrier with light from the light source passing through the phosphor carrier. A diffuser dome is included that is mounted over the optical cavity, with light from the optical cavity passing through the diffuser dome. The properties of the diffuser, such as geometry, scattering properties of the scattering layer, surface roughness or smoothness, and spatial distribution of the scattering layer properties may be used to control various lamp properties such as color uniformity and light intensity distribution as a function of viewing angle.

  16. A comparison of thick film and thin film traffic stripes

    E-Print Network [OSTI]

    Keese, Charles J

    1952-01-01T23:59:59.000Z

    Striys. . . Pigmented Bitusmn Stripes . Asphalt %uilt-Upa Striye vith Pigmented Portland Cement Mortar Cover Course 38 . ~ 41 Thin Film Stripes Used for Comparison Results of Comparing Thick Film Stripes and Thin Film Paint Stripes . ~ ~ ~ ~ ~ 43... was aspbaltio oonorets. The pavement in Test Areas 2y 3p and 4 vas portland cesmnh ooncrete, Two test areas (3 and 4) vere located in such manner as to provide uninterrupted flow of traffic over tbs entire length of the test area. The other two test areas (1...

  17. EECBG Success Story: Getting Traffic Lights Talking to Improve Topeka's

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742Energy China U.S.ContaminationJulySavannah River Site forCommunity'Department ofDepartmentTraffic

  18. A portable time-domain LED fluorimeter for nanosecond fluorescence lifetime measurements

    SciTech Connect (OSTI)

    Wang, Hongtao; Salthouse, Christopher D., E-mail: salthouse@ecs.umass.edu [Electrical and Computer Engineering Department, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Center for Personalized Health Monitoring, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Qi, Ying; Mountziaris, T. J. [Center for Personalized Health Monitoring, University of Massachusetts, Amherst, Massachusetts 01003 (United States) [Center for Personalized Health Monitoring, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Chemical Engineering Department, University of Massachusetts, Amherst, Massachusetts 01003 (United States)

    2014-05-15T23:59:59.000Z

    Fluorescence lifetime measurements are becoming increasingly important in chemical and biological research. Time-domain lifetime measurements offer fluorescence multiplexing and improved handling of interferers compared with the frequency-domain technique. In this paper, an all solid-state, filterless, and highly portable light-emitting-diode based time-domain fluorimeter (LED TDF) is reported for the measurement of nanosecond fluorescence lifetimes. LED based excitation provides more wavelengths options compared to laser diode based excitation, but the excitation is less effective due to the uncollimated beam, less optical power, and longer latency in state transition. Pulse triggering and pre-bias techniques were implemented in our LED TDF to improve the peak optical power to over 100 mW. The proposed pulsing circuit achieved an excitation light fall time of less than 2 ns. Electrical resetting technique realized a time-gated photo-detector to remove the interference of the excitation light with fluorescence. These techniques allow the LED fluorimeter to accurately measure the fluorescence lifetime of fluorescein down to concentration of 0.5 ?M. In addition, all filters required in traditional instruments are eliminated for the non-attenuated excitation/emission light power. These achievements make the reported device attractive to biochemical laboratories seeking for highly portable lifetime detection devices for developing sensors based on fluorescence lifetime changes. The device was initially validated by measuring the lifetimes of three commercial fluorophores and comparing them with reported lifetime data. It was subsequently used to characterize a ZnSe quantum dot based DNA sensor.

  19. Lumen and Chromaticity Maintenance of LED PAR38 Lamps Operated in Steady-State Conditions

    SciTech Connect (OSTI)

    Royer, Michael P.

    2014-12-01T23:59:59.000Z

    The lumen depreciation and color shift of 38 different lamps (32 LED, 2 CFL, 1 ceramic metal halide [CMH], 3 halogen) were monitored in a specially developed automated long-term test apparatus (ALTA2) for nearly 14,000 hours. Five samples of each lamp model were tested, with measurements recorded on a weekly basis. The lamps were operated continuously at a target ambient temperature between 44°C and 45°C.

  20. Observed Minimum Illuminance Threshold for Night Market Vendors in Kenya who use LED Lamps

    SciTech Connect (OSTI)

    Johnstone, Peter; Jacobson, Arne; Mills, Evan; Radecsky, Kristen

    2009-03-21T23:59:59.000Z

    Creation of light for work, socializing, and general illumination is a fundamental application of technology around the world. For those who lack access to electricity, an emerging and diverse range of LED based lighting products hold promise for replacing and/or augmenting their current fuel-based lighting sources that are costly and dirty. Along with analysis of environmental factors, economic models for total cost-ofownership of LED lighting products are an important tool for studying the impacts of these products as they emerge in markets of developing countries. One important metric in those models is the minimum illuminance demanded by end-users for a given task before recharging the lamp or replacing batteries. It impacts the lighting service cost per unit time if charging is done with purchased electricity, batteries, or charging services. The concept is illustrated in figure 1: LED lighting products are generally brightest immediately after the battery is charged or replaced and the illuminance degrades as the battery is discharged. When a minimum threshold level of illuminance is reached, the operational time for the battery charge cycle is over. The cost to recharge depends on the method utilized; these include charging at a shop at a fixed price per charge, charging on personal grid connections, using solar chargers, and purchasing dry cell batteries. This Research Note reports on the observed"charge-triggering" illuminance level threshold for night market vendors who use LED lighting products to provide general and task oriented illumination. All the study participants charged with AC power, either at a fixed-price charge shop or with electricity at their home.