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Sample records for led commercial garage

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

    SciTech Connect

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

    2008-11-11

    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

  2. Use of Occupancy Sensors in LED Parking Lot and Garage Applications: Early Experiences

    SciTech Connect

    Kinzey, Bruce R.; Myer, Michael; Royer, Michael P.; Sullivan, Greg P.

    2012-11-07

    Occupancy sensor systems are gaining traction as an effective technological approach to reducing energy use in exterior commercial lighting applications. Done correctly, occupancy sensors can substantially enhance the savings from an already efficient lighting system. However, this technology is confronted by several potential challenges and pitfalls that can leave a significant amount of the prospective savings on the table. This report describes anecdotal experiences from field installations of occupancy sensor controlled light-emitting diode (LED) lighting at two parking structures and two parking lots. The relative levels of success at these installations reflect a marked range of potential outcomes: from an additional 76% in energy savings to virtually no additional savings. Several issues that influenced savings were encountered in these early stage installations and are detailed in the report. Ultimately, care must be taken in the design, selection, and commissioning of a sensor-controlled lighting installation, else the only guaranteed result may be its cost.

  3. Retinal damage induced by commercial light emitting diodes (LEDs).

    PubMed

    Jaadane, Imene; Boulenguez, Pierre; Chahory, Sabine; Carré, Samuel; Savoldelli, Michèle; Jonet, Laurent; Behar-Cohen, Francine; Martinsons, Christophe; Torriglia, Alicia

    2015-07-01

    Spectra of "white LEDs" are characterized by an intense emission in the blue region of the visible spectrum, absent in daylight spectra. This blue component and the high intensity of emission are the main sources of concern about the health risks of LEDs with respect to their toxicity to the eye and the retina. The aim of our study was to elucidate the role of blue light from LEDs in retinal damage. Commercially available white LEDs and four different blue LEDs (507, 473, 467, and 449nm) were used for exposure experiments on Wistar rats. Immunohistochemical stain, transmission electron microscopy, and Western blot were used to exam the retinas. We evaluated LED-induced retinal cell damage by studying oxidative stress, stress response pathways, and the identification of cell death pathways. LED light caused a state of suffering of the retina with oxidative damage and retinal injury. We observed a loss of photoreceptors and the activation of caspase-independent apoptosis, necroptosis, and necrosis. A wavelength dependence of the effects was observed. Phototoxicity of LEDs on the retina is characterized by a strong damage of photoreceptors and by the induction of necrosis. PMID:25863264

  4. 4. TENSTALL GARAGE. GARAGE DOOR DETAIL. VIEW TO WEST. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. TEN-STALL GARAGE. GARAGE DOOR DETAIL. VIEW TO WEST. - Rainbow Hydroelectric Facility, Ten Stall Garage, On north bank of Missouri River 2 miles Northeast of Great Falls, & end of Rainbow Dam Road, Great Falls, Cascade County, MT

  5. SCHOOL BUS GARAGE.

    ERIC Educational Resources Information Center

    PALLIDINO, STEVE; STRIPLING, CHARLES W.

    COUNTY BOARDS, COUNTY SUPERINTENDENTS, SCHOOL PERSONNEL, AND ARCHITECTS PLANNING BUS GARAGE FACILITIES WILL FIND THIS PUBLICATION USEFUL. DECISIONS NEED TO BE MADE IN REGARD TO WHO WILL USE THE GARAGE, WHAT PURPOSE IT SHOULD SERVE, AND WHAT KIND OF SPACES ARE NEEDED. SITE SELECTION FACTORS TO BE CONSIDERED ARE LOCATION, PARKING SPACE, MANEUVERING…

  6. SCHOOL BUS GARAGES, 1966 REVISION.

    ERIC Educational Resources Information Center

    JOHNSON, HERBERT F.

    STANDARDS AND RECOMMENDATIONS ARE GIVEN FOR THE DESIGN AND CONSTRUCTION OF SCHOOL BUS GARAGES INCLUDING BRIEF DISCUSSIONS OF--(1) SITE DEVELOPMENT, (2) DESIGN AND CONSTRUCTION, AND (3) MECHANICAL (HEATING, PLUMBING, AND VENTILATION) AND ELECTRICAL FACTORS. (JT)

  7. Garage Band or GarageBand[R]? Remixing Musical Futures

    ERIC Educational Resources Information Center

    Vakeva, Lauri

    2010-01-01

    In this paper, I suggest that it is perhaps time to consider the pedagogy of popular music in more extensive terms than conventional rock band practices have to offer. One direction in which this might lead is the expansion of the informal pedagogy based on a "garage band" model to encompass various modes of digital artistry wherever this artistry…

  8. Twenty-First Century Garage.

    ERIC Educational Resources Information Center

    Bushweller, Kevin

    1997-01-01

    The experiences of several school bus garages around the country show that it is possible to modernize equipment and upgrade training while also holding the line on costs. Computer software is used to track servicing, inventory, and other information about a bus fleet. Related factors in improved bus maintenance are the quality of the vehicles and…

  9. Interior view of garage facing back wall (east) Presidio ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view of garage facing back wall (east) - Presidio of San Francisco, Officers' Vehicles Garage, 1055 General Kennedy Avenue, Letterman Hospital Complex, San Francisco, San Francisco County, CA

  10. 1. CONTEXT VIEW OF GARAGE COMPLEX AT SOUTHEAST END OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. CONTEXT VIEW OF GARAGE COMPLEX AT SOUTHEAST END OF OPERATOR'S CAMP SHOWING MECHANIC'S GARAGE AT RIGHT, 4-CAR GARAGE AT CENTER, AND 3-CAR GARAGE AT LEFT. VIEW TO SOUTHEAST. - Holter Hydroelectric Facility, End of Holter Dam Road, Wolf Creek, Lewis and Clark County, MT

  11. 3. CONTEXT VIEW OF GARAGE COMPLEX AT SOUTHEAST END OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. CONTEXT VIEW OF GARAGE COMPLEX AT SOUTHEAST END OF OPERATOR' CAMP SHOWING MECHANIC'S GARAGE NO. 48 AT LEFT, 4-CAR GARAGE AT CENTER, AND 3-CAR GARAGE AT RIGHT. VIEW TO NORTH-NORTHWEST - Holter Hydroelectric Facility, End of Holter Dam Road, Wolf Creek, Lewis and Clark County, MT

  12. 2. CONTEXT VIEW OF GARAGE COMPLEX AT SOUTHEAST END OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. CONTEXT VIEW OF GARAGE COMPLEX AT SOUTHEAST END OF OPERATOR'S CAMP SHOWING MECHANIC'S GARAGE AT RIGHT, 4-CAR GARAGE AT CENTER, AND 3-CAR GARAGE AT LEFT. VIEW TO SOUTHWEST. - Holter Hydroelectric Facility, End of Holter Dam Road, Wolf Creek, Lewis and Clark County, MT

  13. Advances toward commercialization of a new generation of low cost (O)LED-based dissolved oxygen and bioanalyte monitors

    NASA Astrophysics Data System (ADS)

    Smith, Alex; Cai, Yuankun; Vengasandra, Srikanth; Shinar, Ruth; Shinar, Joseph

    2010-08-01

    Recent advances toward commercialization of a new generation of low-cost LED- and OLED-based monitors for dissolved oxygen (DO), and multiple (bio)analytes such as glucose, lactate, alcohol, and cholesterol are described. The design of the DO monitors, which contain no optical fibers, filters, mirrors, or lens, is significantly simpler and consequently lower-cost than that of commercial LED-based DO monitors. The multiple (bio)analyte monitors are based on a DO monitor and the oxidase enzyme specific to each analyte. The potential advantages and disadvantages of the OLED- vs LED-based monitors is also discussed.

  14. Good-bye Garage, Hello CCD

    ERIC Educational Resources Information Center

    Augur, Eleanor

    1977-01-01

    The idea of having a religious education center in a four car garage may sound ridiculous to some but to the parishioners of Saint George's Church in Guilford, Connecticut, it was heaven-sent. (Author/RK)

  15. Automated parking garage system model

    NASA Technical Reports Server (NTRS)

    Collins, E. R., Jr.

    1975-01-01

    A one-twenty-fifth scale model of the key components of an automated parking garage system is described. The design of the model required transferring a vehicle from an entry level, vertically (+Z, -Z), to a storage location at any one of four storage positions (+X, -X, +Y, +Y, -Y) on the storage levels. There are three primary subsystems: (1) a screw jack to provide the vertical motion of the elevator, (2) a cam-driven track-switching device to provide X to Y motion, and (3) a transfer cart to provide horizontal travel and a small amount to vertical motion for transfer to the storage location. Motive power is provided by dc permanent magnet gear motors, one each for the elevator and track switching device and two for the transfer cart drive system (one driving the cart horizontally and the other providing the vertical transfer). The control system, through the use of a microprocessor, provides complete automation through a feedback system which utilizes sensing devices.

  16. INTERIOR VIEW OF THE OVERHEAD GARAGE DOOR. SHOWING THE LARGE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR VIEW OF THE OVERHEAD GARAGE DOOR. SHOWING THE LARGE OPENING WITH CAST STONE SILL IN THE EXTERIOR GARAGE WALL AT LEFT. VIEW FACING NORTHWEST. - Hickam Field, Officers' Housing Type F, 602 Beard Avenue, Honolulu, Honolulu County, HI

  17. View of front of garage, bays 14, facing northeast ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of front of garage, bays 1-4, facing northeast - Presidio of San Francisco, Officers' Vehicles Garage, 1055 General Kennedy Avenue, Letterman Hospital Complex, San Francisco, San Francisco County, CA

  18. View of garage interior from northern bay looking south. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of garage interior from northern bay looking south. - Presidio of San Francisco, Officers' Vehicles Garage, 1055 General Kennedy Avenue, Letterman Hospital Complex, San Francisco, San Francisco County, CA

  19. View of back of garage, windows of bays 13, facing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of back of garage, windows of bays 1-3, facing southwest. - Presidio of San Francisco, Officers' Vehicles Garage, 1055 General Kennedy Avenue, Letterman Hospital Complex, San Francisco, San Francisco County, CA

  20. View of front of garage, bays 37, facing south ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of front of garage, bays 3-7, facing south - Presidio of San Francisco, Officers' Vehicles Garage, 1055 General Kennedy Avenue, Letterman Hospital Complex, San Francisco, San Francisco County, CA

  1. View of front of garage bays 57, facing northeast. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of front of garage bays 5-7, facing northeast. - Presidio of San Francisco, Officers' Vehicles Garage, 1055 General Kennedy Avenue, Letterman Hospital Complex, San Francisco, San Francisco County, CA

  2. View of front and side of garage, bays 67, facing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of front and side of garage, bays 6-7, facing northeast. - Presidio of San Francisco, Officers' Vehicles Garage, 1055 General Kennedy Avenue, Letterman Hospital Complex, San Francisco, San Francisco County, CA

  3. View of front and side of garage, bay 7, facing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of front and side of garage, bay 7, facing east. - Presidio of San Francisco, Officers' Vehicles Garage, 1055 General Kennedy Avenue, Letterman Hospital Complex, San Francisco, San Francisco County, CA

  4. Interior view of garage showing roof, post and beam, and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view of garage showing roof, post and beam, and stored materials. - Presidio of San Francisco, Officers' Vehicles Garage, 1055 General Kennedy Avenue, Letterman Hospital Complex, San Francisco, San Francisco County, CA

  5. View of front of garage, detail of building number over ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of front of garage, detail of building number over bay 4. - Presidio of San Francisco, Officers' Vehicles Garage, 1055 General Kennedy Avenue, Letterman Hospital Complex, San Francisco, San Francisco County, CA

  6. 2. View looking south, showing house, service wing, garage, connection ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. View looking south, showing house, service wing, garage, connection to blacksmith shop/garage, setting - Lamprey House, South side of Dover Road, 0.05 mile east of Goboro Road, Epsom, Merrimack County, NH

  7. 4. MECHANIC'S GARAGE. SOUTHWEST CORNER, AND WEST AND SOUTH SIDES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. MECHANIC'S GARAGE. SOUTHWEST CORNER, AND WEST AND SOUTH SIDES OF ADDITION. VIEW TO NORTHEAST. - Holter Hydroelectric Facility, Mechanic's Garage, End of Holter Dam Road, Wolf Creek, Lewis and Clark County, MT

  8. 1. TWOSTALL GARAGE. FRONT (SOUTHWEST) SIDE. VIEW TO NORTHEAST. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. TWO-STALL GARAGE. FRONT (SOUTHWEST) SIDE. VIEW TO NORTHEAST. - Rainbow Hydroelectric Facility, Two Stall Garage, On north bank of Missouri River 2 miles Northeast of Great Falls, & end of Rainbow Dam Road, Great Falls, Cascade County, MT

  9. 1. THREESTALL GARAGE. SOUTHEAST AND NORTHEAST SIDES. VIEW TO WEST. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. THREE-STALL GARAGE. SOUTHEAST AND NORTHEAST SIDES. VIEW TO WEST. - Rainbow Hydroelectric Facility, Three Stall Garage, On north bank of Missouri River 2 miles Northeast of Great Falls, & end of Rainbow Dam Road, Great Falls, Cascade County, MT

  10. 3. TENSTALL GARAGE. NORTH AND WEST SIDES. VIEW TO SOUTHEAST. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. TEN-STALL GARAGE. NORTH AND WEST SIDES. VIEW TO SOUTHEAST. - Rainbow Hydroelectric Facility, Ten Stall Garage, On north bank of Missouri River 2 miles Northeast of Great Falls, & end of Rainbow Dam Road, Great Falls, Cascade County, MT

  11. 2. THREESTALL GARAGE. NORTHEAST SIDE. VIEW TO SOUTHWEST. Rainbow ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. THREE-STALL GARAGE. NORTHEAST SIDE. VIEW TO SOUTHWEST. - Rainbow Hydroelectric Facility, Three Stall Garage, On north bank of Missouri River 2 miles Northeast of Great Falls, & end of Rainbow Dam Road, Great Falls, Cascade County, MT

  12. 3. THREESTALL GARAGE. NORTHWEST AND SOUTHWEST SIDES. VIEW TO EAST. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. THREE-STALL GARAGE. NORTHWEST AND SOUTHWEST SIDES. VIEW TO EAST. - Rainbow Hydroelectric Facility, Three Stall Garage, On north bank of Missouri River 2 miles Northeast of Great Falls, & end of Rainbow Dam Road, Great Falls, Cascade County, MT

  13. 3. TWOSTALL GARAGE SOUTHEAST AND NORTHEAST SIDES. VIEW TO WEST. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. TWO-STALL GARAGE SOUTHEAST AND NORTHEAST SIDES. VIEW TO WEST. - Rainbow Hydroelectric Facility, Two Stall Garage, On north bank of Missouri River 2 miles Northeast of Great Falls, & end of Rainbow Dam Road, Great Falls, Cascade County, MT

  14. O1 DETACHED GARAGE FRONT ELEVATION. Naval Magazine Lualualei, Headquarters ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    O-1 DETACHED GARAGE FRONT ELEVATION. - Naval Magazine Lualualei, Headquarters Branch, Garage for Building O, Sixty-sixth Street between Constitution & Amberjack Streets, behind Building O, Pearl City, Honolulu County, HI

  15. O1 DETACHED GARAGE FRONT AND SIDE VIEW. Naval Magazine ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    O-1 DETACHED GARAGE FRONT AND SIDE VIEW. - Naval Magazine Lualualei, Headquarters Branch, Garage for Building O, Sixty-sixth Street between Constitution & Amberjack Streets, behind Building O, Pearl City, Honolulu County, HI

  16. Bexar County Parking Garage Photovoltaic Panels

    SciTech Connect

    Weir, Golda

    2012-01-23

    The main objective of the Bexar County Parking Garage Photovoltaic (PV) Panel project is to install a PV System that will promote the use of renewable energy. This project will also help sustain Bexar County ongoing greenhouse gas emissions reduction and energy efficiency goals. The scope of this project includes the installation of a 100-kW system on the top level of a new 236,285 square feet parking garage. The PV system consists of 420 solar panels that covers 7,200 square feet and is tied into the electric-grid. It provides electricity to the office area located within the garage. The estimated annual electricity production of the PV system is 147,000 kWh per year.

  17. GARDEN (FOREGROUND), GARAGE (CENTER), AND PUMPHOUSE, LOOKING NORTHWEST Irvine ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GARDEN (FOREGROUND), GARAGE (CENTER), AND PUMPHOUSE, LOOKING NORTHWEST - Irvine Ranch Agricultural Headquarters, Carillo Tenant House, Southwest of Intersection of San Diego & Santa Ana Freeways, Irvine, Orange County, CA

  18. GARAGE, SOUTH (REAR) AND EAST SIDE, LOOKING NORTHWEST Irvine ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GARAGE, SOUTH (REAR) AND EAST SIDE, LOOKING NORTHWEST - Irvine Ranch Agricultural Headquarters, Carillo Tenant House, Southwest of Intersection of San Diego & Santa Ana Freeways, Irvine, Orange County, CA

  19. 4. Relationship of claim house, residence, and garage to each ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Relationship of claim house, residence, and garage to each other and immediate surroundings, looking northeast - George Spangerberger Farmstead, 2012 West Illinois Avenue, South Hutchinson, Reno County, KS

  20. 2. GARAGE. VIEW LOOKING NORTHWEST. THE ORIGINAL DOOR IN THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. GARAGE. VIEW LOOKING NORTHWEST. THE ORIGINAL DOOR IN THE SOUTHEND HAS BEEN INFILLED. THE DARK RECTANGLE (AT RIGHT OF WINDOW) IS A PIECE OF PLYWOOD WITH AN ELECTRICAL RECEPTACLE ITS PURPOSE WAS NOT DETERMINED. - Tonto Ranger Station, Garage, Forest Service Road 65 at Tonto Wash, Skull Valley, Yavapai County, AZ

  1. 56. View of street level entrance to parking garage elevators ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    56. View of street level entrance to parking garage elevators and detail of aluminum and glass connection to brick from east side of 1946/1948 store for homes and parking garage. - Rich's Downtown Department Store, 45 Broad Street, Atlanta, Fulton County, GA

  2. Air Leakage and Air Transfer Between Garage and Living Space

    SciTech Connect

    Rudd, Armin

    2014-09-01

    This research project focused on evaluation of air transfer between the garage and living space in a single-family detached home constructed by a production homebuilder in compliance with the 2009 International Residential Code and the 2009 International Energy Conservation Code. The project gathered important information about the performance of whole-building ventilation systems and garage ventilation systems as they relate to minimizing flow of contaminated air from garage to living space. A series of 25 multi-point fan pressurization tests and additional zone pressure diagnostic testing characterized the garage and house air leakage, the garage-to-house air leakage, and garage and house pressure relationships to each other and to outdoors using automated fan pressurization and pressure monitoring techniques. While the relative characteristics of this house may not represent the entire population of new construction configurations and air tightness levels (house and garage) throughout the country, the technical approach was conservative and should reasonably extend the usefulness of the results to a large spectrum of house configurations from this set of parametric tests in this one house. Based on the results of this testing, the two-step garage-to-house air leakage test protocol described above is recommended where whole-house exhaust ventilation is employed.

  3. 3. DETAIL VIEW OF STATION GARAGE SHOWING SOUTHEAST FACADE WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. DETAIL VIEW OF STATION GARAGE SHOWING SOUTHEAST FACADE WITH WATER SOFTENER BUILDING (BUILDING NO. 42) TO LEFT AND ANIMAL HOUSE (BUILDING NO. 26) TO REAR. VIEW TO WEST. - VA Medical Center, Aspinwall Division, Station Garage, 5103 Delafield Avenue, Aspinwall, Allegheny County, PA

  4. GARAGE EXTERIOR EAST SIDE AND REAR SHOWING PIER SUPPORTS UNDER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GARAGE EXTERIOR EAST SIDE AND REAR SHOWING PIER SUPPORTS UNDER SHED-ROOFED REAR STORAGE COMPARTMENT, ASBESTOS SIDING OVER ORIGINAL WOOD SIDING, AND SINGLE CASEMENT WINDOW OVER REAR STORAGE COMPARTMENT. VIEW TO NORTHWEST - Big Creek Hydroelectric System, Big Creek Town, Operator House Garage, Orchard Avenue south of Huntington Lake Road, Big Creek, Fresno County, CA

  5. 1. TENSTALL GARAGE. FRONT (EAST) AND SOUTH SIDES. VIEW TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. TEN-STALL GARAGE. FRONT (EAST) AND SOUTH SIDES. VIEW TO NORTHWEST. - Rainbow Hydroelectric Facility, Ten Stall Garage, On north bank of Missouri River 2 miles Northeast of Great Falls, & end of Rainbow Dam Road, Great Falls, Cascade County, MT

  6. 2. TENSTALL GARAGE. FRONT (EAST) AND PARTIAL NORTH SIDES. VIEW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. TEN-STALL GARAGE. FRONT (EAST) AND PARTIAL NORTH SIDES. VIEW TO SOUTHWEST. - Rainbow Hydroelectric Facility, Ten Stall Garage, On north bank of Missouri River 2 miles Northeast of Great Falls, & end of Rainbow Dam Road, Great Falls, Cascade County, MT

  7. 2. TWOSTALL GARAGE. FRONT (SOUTHWEST) AND NORTHWEST SIDES. VIEW TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. TWO-STALL GARAGE. FRONT (SOUTHWEST) AND NORTHWEST SIDES. VIEW TO EAST. - Rainbow Hydroelectric Facility, Two Stall Garage, On north bank of Missouri River 2 miles Northeast of Great Falls, & end of Rainbow Dam Road, Great Falls, Cascade County, MT

  8. Air Leakage and Air Transfer Between Garage and Living Space

    SciTech Connect

    Rudd, A.

    2014-09-01

    This research project focused on evaluation of air transfer between the garage and living space in a single-family detached home constructed by a production homebuilder in compliance with the 2009 International Residential Code and the 2009 International Energy Conservation Code. The project gathered important information about the performance of whole-building ventilation systems and garage ventilation systems as they relate to minimizing flow of contaminated air from garage to living space. A series of 25 multi-point fan pressurization tests and additional zone pressure diagnostic testing characterized the garage and house air leakage, the garage-to-house air leakage, and garage and house pressure relationships to each other and to outdoors using automated fan pressurization and pressure monitoring techniques. While the relative characteristics of this house may not represent the entire population of new construction configurations and air tightness levels (house and garage) throughout the country, the technical approach was conservative and should reasonably extend the usefulness of the results to a large spectrum of house configurations from this set of parametric tests in this one house. Based on the results of this testing, the two-step garage-to-house air leakage test protocol described above is recommended where whole-house exhaust ventilation is employed. For houses employing whole-house supply ventilation (positive pressure) or balanced ventilation (same pressure effect as the Baseline condition), adherence to the EPA Indoor airPLUS house-to-garage air sealing requirements should be sufficient to expect little to no garage-to-house air transfer.

  9. Field evaluation of ventilation system performance in enclosed parking garages

    SciTech Connect

    Ayari, A.M.; Grot, D.A.; Krarti, M.

    2000-07-01

    This paper summarizes the results of a field study to determine the ventilation requirements and the contaminant levels in existing enclosed parking garages. The testing was conducted in seven parking garages with different sizes, traffic flow patterns, vehicle types, and locations. In particular, the study compares the actual ventilation rates measured using the tracer gas technique with the ventilation requirements of ANSI/ASHRAE Standard 62-1989. In addition, the field test evaluated the effectiveness of the existing ventilation systems in maintaining acceptable contaminant levels within enclosed parking garages.

  10. Migration of volatile organic compounds from attached garages to residences: a major exposure source.

    PubMed

    Batterman, Stuart; Jia, Chunrong; Hatzivasilis, Gina

    2007-06-01

    Vehicle garages often contain high concentrations of volatile organic compounds (VOCs) that may migrate into adjoining residences. This study characterizes VOC concentrations, exposures, airflows, and source apportionments in 15 single-family houses with attached garages in southeast Michigan. Fieldwork included inspections to determine possible VOC sources, deployment of perfluorocarbon tracer (PFT) sources in garages and occupied spaces, and measurements of PFT, VOC, and CO(2) concentrations over a 4-day period. Air exchange rates (AERs) averaged 0.43+/-0.37 h(-1) in the houses and 0.77+/-0.51 h(-1) in the garages, and air flows from garages to houses averaged 6.5+/-5.3% of the houses' overall air exchange. A total of 39 VOC species were detected indoors, 36 in the garage, and 20 in ambient air. Garages showed high levels of gasoline-related VOCs, e.g., benzene averaged 37+/-39 microg m(-3). Garage/indoor ratios and multizone IAQ models show that nearly all of the benzene and most of the fuel-related aromatics in the houses resulted from garage sources, confirming earlier reports that suggested the importance of attached garages. Moreover, doses of VOCs such as benzene experienced by non-smoking individuals living in houses with attached garages are dominated by emissions in garages, a result of exposures occurring in both garage and house microenvironments. All of this strongly suggests the need to better control VOC emissions in garages and contaminant migration through the garage-house interface. PMID:17350611

  11. 8. INTERIOR, FIRE ALARM CONTROL ROOM (NORTH OF MAIN GARAGE), ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. INTERIOR, FIRE ALARM CONTROL ROOM (NORTH OF MAIN GARAGE), FROM ENTRYWAY, LOOKING NORTH, SHOWING ADDITIONAL 'GAMEWELL' FIRE ALARM SYSTEMS. - Oakland Naval Supply Center, Firehouse, East of Fourth Street, between A & B Streets, Oakland, Alameda County, CA

  12. 2. FIRST FLOOR, FIRE ENGINE GARAGE, VIEW SHOWING STAIRWAY AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. FIRST FLOOR, FIRE ENGINE GARAGE, VIEW SHOWING STAIRWAY AND FIRE POLE (NOTE THE STAMPWORK ON WALL AND CEILING) - Hoboken Fire Engine Company Number Two, 1313 Washington Street, Hoboken, Hudson County, NJ

  13. Section A, view of cooling water pipes and parking garage ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Section A, view of cooling water pipes and parking garage entrance/exit on west slurry wall, looking west. (BH) - World Trade Center Site, Bounded by Vesey, Church, Liberty Streets, & Route 9A, New York County, NY

  14. Aerial view showing US 93, Switchyards, Visitor Center Parking Garage, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Aerial view showing US 93, Switchyards, Visitor Center Parking Garage, Hoover Dam, and Colorado River Canyon in Nevada - Hoover Dam, Spanning Colorado River at Route 93, Boulder City, Clark County, NV

  15. 5. GENERAL VIEW OF GARAGE AREA FROM WEST; STEPS TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. GENERAL VIEW OF GARAGE AREA FROM WEST; STEPS TO WEST FRONT ENTRANCE VISABLE TO THE RIGHT - Isaac N. Hagan House, Kentuck Knob, U.S. Route 40 vicinity (Stewart Township), Chalkhill, Fayette County, PA

  16. Everett Weinreb, Photographer, April 1989 GARAGE BEHIND HOUSE, EAST (FRONT) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Everett Weinreb, Photographer, April 1989 GARAGE BEHIND HOUSE, EAST (FRONT) AND WEST SIDE, LOOKING SOUTHEAST - Irvine Ranch Agricultural Headquarters, Boyd Tenant House, Southeast of Intersection of San Diego & Santa Ana Freeways, Irvine, Orange County, CA

  17. Everett Weinreb, Photographer, April 1989 GARAGE BEHIND HOUSE, WEST (REAR), ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Everett Weinreb, Photographer, April 1989 GARAGE BEHIND HOUSE, WEST (REAR), LOOKING NORTHEAST - Irvine Ranch Agricultural Headquarters, Boyd Tenant House, Southeast of Intersection of San Diego & Santa Ana Freeways, Irvine, Orange County, CA

  18. Everett Weinreb, Photographer, April 1989 GARAGE BEHIND HOUSE, SOUTH SIDE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Everett Weinreb, Photographer, April 1989 GARAGE BEHIND HOUSE, SOUTH SIDE AND WEST (REAR) FACADES, LOOKING NORTHEAST - Irvine Ranch Agricultural Headquarters, Boyd Tenant House, Southeast of Intersection of San Diego & Santa Ana Freeways, Irvine, Orange County, CA

  19. Everett Weinreb, Photographer, April 1989 GARAGE BEHIND HOUSE, EAST (FRONT), ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Everett Weinreb, Photographer, April 1989 GARAGE BEHIND HOUSE, EAST (FRONT), LOOKING WEST - Irvine Ranch Agricultural Headquarters, Boyd Tenant House, Southeast of Intersection of San Diego & Santa Ana Freeways, Irvine, Orange County, CA

  20. GARAGE (L) IN RELATION TO TENANT HOUSE (R), LOOKING SOUTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GARAGE (L) IN RELATION TO TENANT HOUSE (R), LOOKING SOUTHWEST - Irvine Ranch Agricultural Headquarters, Carillo Tenant House, Southwest of Intersection of San Diego & Santa Ana Freeways, Irvine, Orange County, CA

  1. 9. LOOKING NORTHWEST TOWARD SOUTHERN SIDES OF BUILDING 1. GARAGE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. LOOKING NORTHWEST TOWARD SOUTHERN SIDES OF BUILDING 1. GARAGE ADDITION AT RIGHT. - Chollas Heights Naval Radio Transmitting Facility, Transmitter Building, 6410 Zero Road, San Diego, San Diego County, CA

  2. 6. VIEW SOUTH TOWARD SOUTHERN PORTION OF BUILDING 1. GARAGE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. VIEW SOUTH TOWARD SOUTHERN PORTION OF BUILDING 1. GARAGE ADDITION AT LEFT. - Chollas Heights Naval Radio Transmitting Facility, Transmitter Building, 6410 Zero Road, San Diego, San Diego County, CA

  3. 19. WINDOW DETAIL, NORTH WALL OF GARAGE ADDITION. VIEW SHOWS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. WINDOW DETAIL, NORTH WALL OF GARAGE ADDITION. VIEW SHOWS CONCRETE BLOCK CONSTRUCTION OF ADDITION. - Chollas Heights Naval Radio Transmitting Facility, Transmitter Building, 6410 Zero Road, San Diego, San Diego County, CA

  4. 8. VIEW EAST, CIVILIAN CONSERVATION CORPS CAMP PARSONS GARAGE, MODERN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. VIEW EAST, CIVILIAN CONSERVATION CORPS CAMP PARSONS GARAGE, MODERN SHED, CIVILIAN CONSERVATION CORPS CAMP PARSONS BLACKSMITH SHOP, AND MODERN SHED. - Parsons Nursery, South side of U.S. Route 219, Parsons, Tucker County, WV

  5. 1. VIEW OF CHICKEN COOP (FEATURE C7), FACING NORTHWEST. GARAGE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. VIEW OF CHICKEN COOP (FEATURE C-7), FACING NORTHWEST. GARAGE (FEATURE C-8) IS VISIBLE IN THE BACKGROUND. - Bell Family Residence, Chicken Coop & Garage, East slope of Buckskin Mountain, Paradise Valley, Humboldt County, NV

  6. 1. View looking south, showing blacksmith house/garage connecting to residential ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. View looking south, showing blacksmith house/garage connecting to residential garage and setting - Lamprey Blacksmith Shop, South side of Dover Road, 0.05 miles east of Goboro Road, Epsom, Merrimack County, NH

  7. Oblique view of garage, looking southwest OvertheHorizon Backscatter Radar ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Oblique view of garage, looking southwest - Over-the-Horizon Backscatter Radar Network, Tulelake Radar Site Receive Sector Four Garage, Unnamed road west of Double Head Road, Tulelake, Siskiyou County, CA

  8. O1 DETACHED GARAGE FRONT ELEVATION W/POLE. Naval Magazine Lualualei, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    O-1 DETACHED GARAGE FRONT ELEVATION W/POLE. - Naval Magazine Lualualei, Headquarters Branch, Garage for Building O, Sixty-sixth Street between Constitution & Amberjack Streets, behind Building O, Pearl City, Honolulu County, HI

  9. Concentrations and emissions of gasoline and other vapors from residential vehicle garages

    NASA Astrophysics Data System (ADS)

    Batterman, Stuart; Hatzivasilis, Gina; Jia, Chunrong

    High concentrations of airborne volatile organic compounds (VOCs) may be present in residential garages due to emissions from vehicles, lawnmowers, storage containers, and many other items stored in the garage. VOC emissions will ultimately be transported into ambient air and, if the garage is attached to a residence or other building, into living spaces. This study reports on VOC concentrations and emissions at 15 residential garages in Michigan that varied in type, size, use and other characteristics. VOCs were measured in garages and in outside air using 4-day passive sampling, thermal desorption, and GC-MS analysis. Effective air exchange rates (AERs) were determined using a perfluorocarbon tracer gas and the constant injection method. A modeling analysis shows the effect of time-varying ventilation. To estimate temporal and spatial variability, concentrations were measured on 7 subsequent occasions at multiple locations in one garage. This garage was well-mixed, and the temporal variation in AERs and concentrations was modest. Across the 15 garages, 36 different VOCs in garage air, and 20 in ambient air, were quantified. Source groups identified and attributed to garage emissions included evaporated gasoline, solvents, paints, oils, and cleaners. Concentrations of gasoline-related VOCs in most garages were high, e.g., benzene levels reached 159 μg m -3 in one garage. TVOC emissions per garage averaged 3.0±4.1 g day -1, and AERs averaged 0.77±0.51 h -1. VOC concentrations and AERs were not strongly correlated to observed house, garage or meteorological factors, but appeared largely dependent on occupant activities (opening of the garage door) and VOC sources present. This study quantifies the importance of attached garages as VOC sources, and the results are significant for understanding and mitigating indoor exposures, and for estimating emissions for source inventory purposes.

  10. High-Tech Garage to Showcase Strategies for Reducing Energy (Fact Sheet)

    SciTech Connect

    Not Available

    2011-08-01

    NREL's new parking garage structure is proving that large garages can be designed and built sustainably at no extra cost. This fact sheet describes the garage's energy and water-saving measures, renewable energy technologies, sustainable and durable building materials, another campus improvements.

  11. 2. POWERHOUSE FOREMAN'S BUNGALOW. CONTEXT VIEW FROM HILL ABOVE GARAGE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. POWERHOUSE FOREMAN'S BUNGALOW. CONTEXT VIEW FROM HILL ABOVE GARAGE SHOWING NORTHEAST AND NORTHWEST FACADES. VIEW TO SOUTH-SOUTHEAST. - Thompson Falls Hydroelectric Project, Power Foreman's Bungalow, On island between Forebay Channel & ClarkFord River, Thompson Falls, Sanders County, MT

  12. General view, looking northeast. Retrofitted into a garage during the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    General view, looking northeast. Retrofitted into a garage during the twentieth century, this building dates from very early in the Lazaretto's history and is believed to have once functioned as a summer kitchen or bake house. - Lazaretto Quarantine Station, Kitchen/Bake House, Wanamaker Avenue and East Second Street, Essington, Delaware County, PA

  13. Learning in the Workplace for Garage Mechanics and Technicians

    ERIC Educational Resources Information Center

    Jans, Ruben, Bollen, Ria,

    2008-01-01

    Employees in technical firms, like garages, need more and more formations. Due to the very fast innovation in technology, lifelong learning is a real need for these labour forces. On the other hand, there are the needed formations very specialized and expensive. Another problem employers faced in these economical sectors in Western Europe is the…

  14. 38. Photocopy of photograph (Pentran file), photographer unknown. Bus garage ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    38. Photocopy of photograph (Pentran file), photographer unknown. Bus garage to left now demolished. Trolley car drivers, maintenance personnel and management staff in 1915. VIEW SOUTH - Newport News & Old Point Railway & Electric Company, Trolley Barn & Administration Building, 3400 Victoria Boulevard, Hampton, Hampton, VA

  15. EXTERIOR PERSPECTIVE OF HOUSE AND MILKROOM LOOKING SOUTHEAST FROM GARAGE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    EXTERIOR PERSPECTIVE OF HOUSE AND MILKROOM LOOKING SOUTHEAST FROM GARAGE (This image shows the gable-roofed punch out entrance into the kitchen that was added in the mid-1980s when the kitchen was remodeled. Penn Cove can be seen in the distance) - Arnold Farm, House, 1948 Arnold Road, Coupeville, Island County, WA

  16. 1. Postandbeam garage (far left), oneroom log cabin (left of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Post-and-beam garage (far left), one-room log cabin (left of center), house (right of center), garden shed and outhouse (far right). View to west-southwest. - William & Lucina Bowe Ranch, County Road 44, 0.1 mile northeast of Big Hole River Bridge, Melrose, Silver Bow County, MT

  17. 7. INTERIOR, MAIN GARAGE, SOUTHERN WALL, FROM CLOSE TO WALL, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. INTERIOR, MAIN GARAGE, SOUTHERN WALL, FROM CLOSE TO WALL, LOOKING SOUTH, SHOWING 'GAMEWELL' FIRE ALARM TAPE CONTROL SYSTEM (TECHNOLOGY CIRCA 1910) AT CENTER, AND ENTRY TO OFFICE AT FAR RIGHT. - Oakland Naval Supply Center, Firehouse, East of Fourth Street, between A & B Streets, Oakland, Alameda County, CA

  18. 4. ROOF OF TWOSTALL GARAGE, SURGE TANK, HOUSE No. 16, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. ROOF OF TWO-STALL GARAGE, SURGE TANK, HOUSE No. 16, RELIEF TANK IN BACKGROUND. VIEW TO SOUTH. - Rainbow Hydroelectric Facility, On north bank of Missouri River 2 miles Northeast of Great Falls, & end of Rainbow Dam Road, Great Falls, Cascade County, MT

  19. 3. FOREMAN'S HOUSE, TENSTALL GARAGE, AND STEPS TO SWIMMING POOL. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. FOREMAN'S HOUSE, TEN-STALL GARAGE, AND STEPS TO SWIMMING POOL. VIEW TO SOUTH-SOUTHWEST. - Rainbow Hydroelectric Facility, On north bank of Missouri River 2 miles Northeast of Great Falls, & end of Rainbow Dam Road, Great Falls, Cascade County, MT

  20. WELLTON GOVERNMENT CAMP, PERMANENT GARAGE TYPE 2G. PLAN, ELEVATIONS, AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    WELLTON GOVERNMENT CAMP, PERMANENT GARAGE TYPE 2-G. PLAN, ELEVATIONS, AND SECTIONS. Drawing 50-308-4553, dated October 21, 1949. U.S. Department of the Interior, Bureau of Reclamation, Yuma, Arizona - Wellton-Mohawk Irrigation System, Permanent Garage Type 2-G, 30611 and 30621 Wellton-Mohawk Drive, Wellton, Yuma County, AZ

  1. View of McKenzieRichey garage showing front opening, the false front, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of McKenzie-Richey garage showing front opening, the false front, metal roofing and horizontal plank siding, facing northeast - McKenzie Property, Garage, North Bank of Sailor Gulch, 750 feet northwest of intersection of U.S.F.S. Roads 651 & 349, Placerville, Boise County, ID

  2. View of McKenzieRichey garage showing east side and north back. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of McKenzie-Richey garage showing east side and north back. Note log construction, house in the background and fence in the foreground, facing southwest - McKenzie Property, Garage, North Bank of Sailor Gulch, 750 feet northwest of intersection of U.S.F.S. Roads 651 & 349, Placerville, Boise County, ID

  3. WELLTON GOVERNMENT CAMP, PERMANENT GARAGE TYPE 1G. PLAN, ELEVATIONS, AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    WELLTON GOVERNMENT CAMP, PERMANENT GARAGE TYPE 1-G. PLAN, ELEVATIONS, AND SECTIONS. Drawing 50-308-4552, dated October 25, 1949. U.S. Department of the Interior, Bureau of Reclamation, Yuma, Arizona - Wellton-Mohawk Irrigation System, Permanent Garage Type 1-G, 30601 Wellton-Mohawk Drive, Wellton, Yuma County, AZ

  4. 77 FR 76003 - Submission for OMB Review; Comment Request- Safety Standard for Automatic Residential Garage Door...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-26

    ... of October 4, 2012 and October 17, 2012 (77 FR 60686, 77 FR 63800), the Consumer Product Safety... COMMISSION Submission for OMB Review; Comment Request-- Safety Standard for Automatic Residential Garage Door... residential garage door operators. DATES: Written comments on this request for extension of approval...

  5. Technology Solutions Case Study: Air Leakage and Air Transfer Between Garage and Living Space, Waldorf, Maryland

    SciTech Connect

    2014-11-01

    In this project, Building Science Corporation worked with production homebuilder K. Hovnanian to evaluate air transfer between the garage and living space in a single-family detached home constructed by a production homebuilder in compliance with the 2009 International Residential Code and the 2009 International Energy Conservation Code. The project gathered important information about the performance of whole-building ventilation systems and garage ventilation systems as they relate to minimizing flow of contaminated air from garage to living space. A series of 25 multipoint fan pressurization tests and additional zone pressure diagnostic testing measured the garage and house air leakage, the garage-to-house air leakage, and garage and house pressure relationships to each other and to outdoors using automated fan pressurization and pressure monitoring techniques. While the relative characteristics of this house may not represent the entire population of new construction configurations and air tightness levels (house and garage) throughout the country, the technical approach was conservative and should reasonably extend the usefulness of the results to a large spectrum of house configurations from this set of parametric tests in this one house. Based on the results of this testing, the two-step garage-to-house air leakage test protocol described above is recommended where whole-house exhaust ventilation is employed. For houses employing whole-house supply ventilation (positive pressure) or balanced ventilation (same pressure effect as the baseline condition), adherence to the EPA Indoor airPLUS house-to-garage air sealing requirements should be sufficient to expect little to no garage-to-house air transfer.

  6. [Prediction and influence factors of the ramp's noise of the entrance or exit of garages].

    PubMed

    Di, Guo-Qing; Zhang, Bang-Jun

    2005-09-01

    Some typical entrances/exits of the underground garages are chosen in urban residential areas. On the basis of the optimization of the positions of the noise sampling points and the groupings of the synchronous sampling points, by means of the acoustical analysis of the noise samples, the relation of the correlative factors, among the ramps' noise of the entrances or exits of the garages, the structure, grade, shape of the ramps, upgrade and downgrade, is studied. The prediction model of the ramp's noise influence of the entrance or exit of the garage is established through amending the noise influence of the entrance or exit of the even concrete road. PMID:16366500

  7. 26. GARAGE AND RETAINING WALLS NEAR SAR3. NOTE SEVEN OAKS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. GARAGE AND RETAINING WALLS NEAR SAR-3. NOTE SEVEN OAKS DAM ROAD CONSTRUCTION SCAR ON MOUNTAINSIDE IN DISTANCE. VIEW TO NORTHWEST. - Santa Ana River Hydroelectric System, Redlands, San Bernardino County, CA

  8. 2. View looking east, showing west elevation of blacksmith shop/garage ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. View looking east, showing west elevation of blacksmith shop/garage and change in slope - Lamprey Blacksmith Shop, South side of Dover Road, 0.05 miles east of Goboro Road, Epsom, Merrimack County, NH

  9. Pumphouse/garage and shed, looking southwest Thomas Murphy Homestead, North ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Pumphouse/garage and shed, looking southwest - Thomas Murphy Homestead, North of John Moulton Homestead, approximately 1,000 feet west of Mormon Row Road, and .25 mile north of Antelope Flats Road, Kelly, Teton County, WY

  10. A One-Piece Lunar Regolith Bag Garage Prototype

    NASA Technical Reports Server (NTRS)

    Smithers, G. A.; Nehls, M. K.; Hovater, M. A.; Evans, S. W.; Miller, J. S.; Broughton, R. M., Jr.; Beale, D.; Kilinc-Balci, F.

    2007-01-01

    Shelter structures on the moon, even in early phases of exploration, should incorporate lunar materials as much as possible. This Technical Memorandum details the design and construction of a prototype for a one-piece regolith bag unpressurized garage concept and a materials testing program to investigate six candidate fabrics to learn how they might perform in the lunar environment. The conceptualization was that a lightweight fabric form be launched from Earth and landed on the lunar surface to be robotically filled with raw lunar regolith. Regolith bag fabric candidates included: Vectran(TM), Nextel(TM), Gore PTFE Fabric(TM), Zylon(TM), Twaron(TM), and Nomex(TM). Tensile (including post radiation exposure), fold, abrasion, and hypervelocity impact testing were performed under ambient conditions, and also performed under cold and elevated temperatures. In some cases, Johnson Space Center lunar simulant (JSC-1) was used in conjunction with testing. A series of preliminary structures was constructed during final prototype design based on the principles of the classic masonry arch. The prototype was constructed of Kevlar(TM) and filled with vermiculite. The structure is free-standing, but has not yet been load tested. Future plans would be to construct higher fidelity prototypes and to conduct appropriate tests of the structure.

  11. LED Update

    SciTech Connect

    Johnson, Mark L.; Gordon, Kelly L.

    2006-09-01

    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.

  12. LED lamp

    SciTech Connect

    Galvez, Miguel; Grossman, Kenneth; Betts, David

    2013-11-12

    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.

  13. Respiratory symptoms and lung function in garage workers and taxi drivers.

    PubMed

    Bener, A; Galadari, I; al-Mutawa, J K; al-Maskari, F; Das, M; Abuzeid, M S

    1998-12-01

    The aim of this study was to determine the prevalence of some respiratory symptoms and possible diseases among occupationally-exposed garage workers and taxi drivers. This study involved 158 garage workers and 165 taxi drivers, matched for age, sex, nationality and duration of employment. The mean age of 158 Indian subcontinent garage workers was 34.4 +/- 10.4 years; their mean height and weight were 167.7 +/- 6.6 cm and 72.0 +/- 12.3 kg respectively, and the mean duration of employment garage workers was 8.8 +/- 7.6 years. The mean age of 165 Indian subcontinent male taxi drivers was 34.5 +/- 7.7 years; their mean height and weight were 168.7 +/- 6.1 cm and 71.3 +/- 12.6 kg respectively; and the mean duration of employment was 7.5 +/- 5.4 years. The data on chronic respiratory symptoms showed that garage workers had higher prevalence of symptoms than taxi drivers being significantly greater for chronic phlegm, (p < 0.007); dyspneoa (p < 0.001); and sinusitis (p < 0.03). A higher prevalence of all acute symptoms was recorded in garage workers than in taxi drivers, although the differences were significant only for throat (p < 0.02), hearing problems (p < 0.002); nose (dryness, bleeding and secretion) (p < 0.008); and low back pain (p < 0.05). Almost all forced spirometric tests in the exposed garage workers were lower than in taxi drivers. The results of stepwise multiple regression analysis showed that only phlegm, sinusitis, hearing problems, nasal catarrh, throat, low back pain, smoking and FEF25-75, variables were statistically significant predictors as risk factors. In conclusion, the present study suggests that a high prevalence of respiratory symptoms is associated with exposure to motor vehicle exhaust emission in garage working places. Long-term working as garage workers in the United Arab Emirates (UAE), may be associated with the development of chronic respiratory symptoms and have effects on their daily life and health. PMID:10076696

  14. A One-Piece Lunar Regolith-Bag Garage Prototype

    NASA Technical Reports Server (NTRS)

    Smithers, Gweneth A.; Nehls, Mary K.; Hovater, Mary A.; Evans, Steven W.; Miller, J. Scott; Broughton, Roy M.; Beale, David; Killing-Balci, Fatma

    2007-01-01

    Shelter structures on the moon, even in early phases of exploration, should incorporate lunar materials as much as possible. We designed and constructed a prototype for a one-piece regolith-bag unpressurized garage concept, and, in parallel, we conducted a materials testing program to investigate six candidate fabrics to learn how they might perform in the lunar environment. In our concept, a lightweight fabric form is launched from Earth to be landed on the lunar surface and robotically filled with raw lunar regolith. In the materials testing program, regolith-bag fabric candidates included: Vectran(TM), Nextel(TM), Gore PTFE Fabric(TM), Zylon(TM), Twaron(TM), and Nomex(TM). Tensile (including post radiation exposure), fold, abrasion, and hypervelocity impact testing were performed under ambient conditions, and, within our current means, we also performed these tests under cold and elevated temperatures. In some cases, lunar simulant (JSC-1) was used in conjunction with testing. Our ambition is to continuously refine our testing to reach lunar environmental conditions to the extent possible. A series of preliminary structures were constructed during design of the final prototype. Design is based on the principles of the classic masonry arch. The prototype was constructed of Kevlar(TM) and filled with vermiculite (fairly close to the weight of lunar regolith on the moon). The structure is free-standing, but has not yet been load tested. Our plan for the future would be to construct higher fidelity mockups with each iteration, and to conduct appropriate tests of the structure.

  15. A One-Piece Lunar Regolith-Bag Garage Prototype

    NASA Technical Reports Server (NTRS)

    Smithers, Gweneth A.; Nehls, Mary K.; Hovater, Mary A.; Evans, Steven W.; Miller, J. Scott; Broughton, Roy M., Jr.; Beale, David; Killinc-Balci, Fatma

    2006-01-01

    Shelter structures on the moon, even in early phases of exploration, should incorporate lunar materials as much as possible. We designed and constructed a prototype for a one-piece regolith-bag unpressurized garage concept, and, in parallel, we conducted a materials testing program to investigate six candidate fabrics to learn how they might perform in the lunar environment. In our concept, a lightweight fabric form is launched from Earth to be landed on the lunar surface and robotically filled with raw lunar regolith. In the materials testing program, regolith-bag fabric candidates included: VectranTM, NextelTM, Gore PTFE FabricTM, ZylonTM TwaronTM and NomexTM. Tensile (including post radiation exposure), fold, abrasion, and hypervelocity impact testing were performed under ambient conditions, and, within our current means, we also performed these tests under cold and elevated temperatures. In some cases, lunar simulant (JSC-1) was used in conjunction with testing. Our ambition is to continuously refine our testing to reach lunar environmental conditions to the extent possible. A series of preliminary structures were constructed during design of the final prototype. Design is based on the principles of the classic masonry arch. The prototype was constructed of KevlarTM and filled with vermiculite (fairly close to the weight of lunar regolith on the moon). The structure is free-standing, but has not yet been load tested. Our plan for the future would be to construct higher fidelty mockups with each iteration, and to conduct appropriate tests of the structure.

  16. Ammothermal Growth of Gan Substrates For Leds: High-Pressure Ammonothermal Process for Bulk Gallium Nitride Crystal Growth for Energy Efficient Commercially Competitive Lighting

    SciTech Connect

    2011-01-01

    Broad Funding Opportunity Announcement Project: The new GaN crystal growth method is adapted from that used to grow quartz crystals, which are very inexpensive and represent the second-largest market for single crystals for electronic applications (after silicon). More extreme conditions are required to grow GaN crystals and therefore a new type of chemical growth chamber was invented that is suitable for large-scale manufacturing. A new process was developed that grows GaN crystals at a rate that is more than double that of current processes. The new technology will enable GaN substrates with best-in-world quality at lowest-in-world prices, which in turn will enable new generations of white LEDs, lasers for full-color displays, and high-performance power electronics.

  17. Light Emitting Diodes (LEDs)

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A special lighting technology was developed for space-based commercial plant growth research on NASA's Space Shuttle. Surgeons have used this technology to treat brain cancer on Earth, in two successful operations. The treatment technique, called Photodynamic Therapy, requires the surgeon to use tiny, pinhead-size Light Emitting Diodes (LEDs) (a source that releases long wavelengths of light ) to activate light-sensitive, tumor-treating drugs. 'A young woman operated on in May 1999 has fully recovered with no complications and no evidence of the tumor coming back,' said Dr. Harry Whelan, a pediatric neurologist at the Medical Hospital of Wisconsin in Milwaukee. Laser light has been used for this type of surgery in the past, but the LED light illuminates through all nearby tissues, reaching parts of a tumor that shorter wavelengths of laser light carnot. The new probe is safer because the longer wavelengths of light are cooler than the shorter wavelengths of laser light, making the LED less likely to injure normal brain tissue near the tumor. It can be used for hours at a time while still remaining cool to the touch. The LED light source is compact, about the size of a briefcase, and can be purchased for a fraction of the cost of a laser. The LEDs, developed and managed by NASA's Marshall Space Flight Center, have been used on seven Space Shuttle flights inside the Microgravity Astroculture Facility. This technology has also been successfully used to further commercial research in crop growth.

  18. Building America Case Study: Air Leakage and Air Transfer Between Garage and Living Space, Waldorf, Maryland (Fact Sheet)

    SciTech Connect

    Not Available

    2014-11-01

    This research project focused on evaluation of air transfer between the garage and living space in a single-family detached home constructed by a production homebuilder in compliance with the 2009 International Residential Code and the 2009 International Energy Conservation Code. The project gathered important information about the performance of whole-building ventilation systems and garage ventilation systems as they relate to minimizing flow of contaminated air from garage to living space. A series of 25 multi-point fan pressurization tests and additional zone pressure diagnostic testing characterized the garage and house air leakage, the garage-to-house air leakage, and garage and house pressure relationships to each other and to outdoors using automated fan pressurization and pressure monitoring techniques. While the relative characteristics of this house may not represent the entire population of new construction configurations and air tightness levels (house and garage) throughout the country, the technical approach was conservative and should reasonably extend the usefulness of the results to a large spectrum of house configurations from this set of parametric tests in this one house. Based on the results of this testing, the two-step garage-to-house air leakage test protocol described above is recommended where whole-house exhaust ventilation is employed. For houses employing whole-house supply ventilation (positive pressure) or balanced ventilation (same pressure effect as the Baseline condition), adherence to the EPA Indoor airPLUS house-to-garage air sealing requirements should be sufficient to expect little to no garage-to-house air transfer.

  19. 18 CFR 367.3940 - Account 394, Tools, shop and garage equipment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Account 394, Tools, shop and garage equipment. 367.3940 Section 367.3940 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE PUBLIC UTILITY HOLDING COMPANY ACT OF 2005, FEDERAL POWER ACT AND NATURAL...

  20. Pricing and Availability Intervention in Vending Machines at Four Bus Garages

    PubMed Central

    Hannan, Peter J; Harnack, Lisa J; Mitchell, Nathan R; Toomey, Traci L; Gerlach, Anne

    2009-01-01

    Objective To evaluate the effects of lowering prices and increasing availability on sales of healthy foods and beverages from 33 vending machines in four bus garages as part of a multi-component worksite obesity prevention intervention. Methods Availability of healthy items was increased to 50% and prices were lowered at least 10% in the vending machines in two metropolitan bus garages for an 18-month period. Two control garages offered vending choices at usual availability and prices. Sales data were collected monthly from each of the vending machines at the four garages. Results Increases in availability to 50% and price reductions of an average of 31% resulted in 10-42% higher sales of the healthy items. Employees were most price-responsive for snack purchases. Conclusions Greater availability and lower prices on targeted food and beverage items from vending machines was associated with greater purchases of these items over an eighteen-month period. Efforts to promote healthful food purchases in worksite settings should incorporate these two strategies. PMID:20061884

  1. 17 CFR 256.309 - Automobiles, other vehicles, and related garage equipment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 3 2011-04-01 2011-04-01 false Automobiles, other vehicles... § 256.309 Automobiles, other vehicles, and related garage equipment. This account shall include the delivered cost of all service company owned automobiles, vans, trucks, and other vehicles used by...

  2. 17 CFR 256.309 - Automobiles, other vehicles, and related garage equipment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Automobiles, other vehicles... § 256.309 Automobiles, other vehicles, and related garage equipment. This account shall include the delivered cost of all service company owned automobiles, vans, trucks, and other vehicles used by...

  3. PRELIMINARY INVESTIGATION OF UNCOMBUSTED AUTO FUEL VAPOR DISPERSION WITHIN A RESIDENTIAL GARAGE MICROENVIRONMENT

    EPA Science Inventory

    Evaporative emissions from vehicles in an attached garage may represent a significant source of indoor pollution and human exposure. ilot field study was undertaken to investigate potential in-house dispersion of evaporative emissions of uncombusted fuels from a vehicle parked in...

  4. Effects of garage employment and tobacco smoking on breathing-zone concentrations of carbonyl compounds.

    PubMed

    Zhang, Lin; Chung, Fung-Lung; Boccia, Laura; Colosimo, Steven; Liu, Weili; Zhang, Junfeng

    2003-01-01

    Exposure to carbonyl compounds may cause adverse health effects. The present study examined whether working in a garage and smoking can significantly affect personal "daily" exposure to a number of important carbonyl compounds. The study was carried out on 37 subjects including 22 garage workers (9 smokers and 13 nonsmokers) and 15 nongarage workers or so-called controls (4 smokers and 11 nonsmokers). Daily exposure was estimated using 48-hour integrated measurement of breathing-zone concentrations. The measurement involved the use of a passive carbonyl sampler and high performance liquid chromatography/fluorescence analysis technique. Each subject was measured for up to three measurement sessions. A wide range of breathing-zone concentrations (unit: microgram per cubic meter) was observed for each of the following carbonyls: formaldehyde (14.1-80.1); acetaldehyde (8.41-80.3); acetone (0.65-1096); acrolein (<0.14-3.71); propionaldehyde (1.08-14.6); crotonaldehyde (<0.13-2.80); benzaldehyde (1.79-9.91); and hexaldehyde (0.122-22.4). Statistical significance of smoking effects and working in a garage effects were assessed using SAS mixed models. The results show that the garage workers had significantly higher levels of formaldehyde and acetaldehyde than the controls, and that the smokers had significantly higher levels of acetaldehyde, propionaldehyde, and hexaldehyde, than the nonsmokers (P<.10). Garage employment and smoking appeared to increase breathing-zone concentrations of crotonaldehyde. In general, within-subject variations were smaller than between-subject variations on 48-hour averaged breathing-zone concentrations of carbonyl compounds. PMID:12809545

  5. Light Emitting Diode (LED)

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A special lighting technology was developed for space-based commercial plant growth research on NASA's Space Shuttle. Surgeons have used this technology to treat brain cancer on Earth, in two successful operations. The treatment technique called photodynamic therapy, requires the surgeon to use tiny pinhead-size Light Emitting Diodes (LEDs) (a source releasing long wavelengths of light) to activate light-sensitive, tumor-treating drugs. Laser light has been used for this type of surgery in the past, but the LED light illuminates through all nearby tissues, reaching parts of a tumor that shorter wavelengths of laser light carnot. The new probe is safer because the longer wavelengths of light are cooler than the shorter wavelengths of laser light, making the LED less likely to injure normal brain tissue near the tumor. It can also be used for hours at a time while still remaining cool to the touch. The LED probe consists of 144 tiny pinhead-size diodes, is 9-inches long, and about one-half-inch in diameter. The small balloon aids in even distribution of the light source. The LED light source is compact, about the size of a briefcase, and can be purchased for a fraction of the cost of a laser. The probe was developed for photodynamic cancer therapy by the Marshall Space Flight Center under a NASA Small Business Innovative Research program grant.

  6. Occupational lead exposure among automotive garage workers – a case study for Jimma town, Ethiopia

    PubMed Central

    2012-01-01

    Background In Ethiopia, although there are numerous small-scale and medium industries which use lead-based raw materials that may pose health risks to workers, there are no workplace regulations for lead exposure. Moreover, there are no studies carried out on the blood lead levels (BLLs) of workers or on the contribution of common workplace practices to lead poisoning. Method A cross-sectional study on the BLLs of 45 automotive garage workers and 40 non-garage workers was carried out in the town of Jimma, Ethiopia. In addition to BLL analysis, data on some risk factors such as smoking, and chewing ‘khat’ (the leaves of Catha adulis) were gathered through structured questionnaires and interviews and data analysis was performed using SPSS (version 16). The t-test was used to compare mean BLLs of study groups. The analysis of variance (ANOVA), Kruskal-Wallis, Pearson chi-square and odds ratio tests were used to investigate the associations between specific job type, smoking and/or ‘khat’ chewing, service years and occurrence of non-specific symptoms with BLLs. Results The mean BLL of the automotive-garage workers was found to be significantly greater than that of the controls. The BLLs of all the lead-exposed individuals were found to be over 10 μg/dL, and 53% of them had BLLs ranging 12 – 20 μg/dL, with the remaining 47% having over 20 μg/dL. The BLL of the workers increased with the duration of working in an automotive garage. Individuals involved in manual car painting comprise a larger percentage (58%) of those with the highest BLLs (≥ 20 μg/dL). Lead accumulation in individuals who chew ‘khat’ in the work place was found to be faster than in those who are not used to chewing ‘khat’. ‘Khat’ is an evergreen shrub native to tropical East Africa, with dark green opposite leaves which are chewed when fresh for their stimulating effects. Conclusion The findings of the study have clearly demonstrated that the BLLs of automotive-garage

  7. Concentrations of vehicle-related air pollutants in an urban parking garage.

    PubMed

    Kim, Sung R; Dominici, Francesca; Buckley, Timothy J

    2007-11-01

    There is growing evidence that traffic-related air pollution poses a public health threat, yet the dynamics of human exposure are not well understood. The urban parking garage is a microenvironment that is of concern but has not been characterized. Using time-resolved measurement methods, we evaluated air toxics levels within an urban parking garage and assessed the influence of vehicle activity and type on their levels. Carbon monoxide (CO) and particle-bound polycyclic aromatic hydrocarbons (pPAH) were measured with direct-reading instruments. Volatile organic compounds (VOCs) were measured in 30 min intervals using a sorbent tube loaded sequential sampler. Vehicle volume and type were evaluated by video recording. Sampling was conducted from June 24 to July 17, 2002. We observed garage traffic median volumes of 71 counts/h on weekdays and 6 counts/h on weekends. The 12-fold reduction in traffic volume from weekday to weekend corresponded with a decrease in median air pollution that varied from a minimum 2- (CO) to a maximum 7 (pPAH)-fold. The actual 30-min median weekday and weekend values were: CO--2.6/1.2 ppm; pPAH--19/2.6 ng/m(3); 1,3-butadiene-0.5/0.2 microg/m(3), MTBE-7.4/0.4 microg/m(3); and benzene-2.7/0.3 microg/m(3). The influence of traffic was quantified using longitudinal models. The pollutant coefficients provide an indication of the average air pollution vehicle source contribution and ranged from 0.31 (CO) to 1.08 (pPAH) percent increase/vehicle count. For some pollutants, a slightly higher (0.5-0.6%) coefficient was observed for light-trucks relative to cars. This study has public health relevance in providing a unique assessment of air pollution levels and source contribution for the urban parking garage. PMID:17716646

  8. Lighting the Great Outdoors: LEDs in Exterior Applications

    SciTech Connect

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

    2008-08-17

    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.

  9. Binary complementary white LED illumination

    NASA Astrophysics Data System (ADS)

    Roberts, John K.

    2001-12-01

    For widespread adoption in general-purpose illumination applications, light-emitting diodes (LEDs) must reliably produce a substantial amount of white light at a reasonable cost. While several white LED technologies appear capable of meeting the implicit technical requirements for illumination, their high purchase price (relative to traditional light sources) has heretofore impeded their market advancement. Binary complementary white (BCW) LED illuminators, first introduced commercially in late 1997, appear to offer great potential for addressing the commercial and technical demands of general-purpose illumination applications. Many properties of BCW LED systems derive from AlInGaP LED chips, the source of up to 80% of the luminous flux projected from BCW devices. This configuration yields a number of benefits, relative to other white LED approaches, including high luminous efficacy, low cost per lumen, and high luminous flux per discrete component. This document describes BCW illumination systems in detail, beginning with a review of generic LED attributes, basic illumination requirements and applied photometric and colorimetric techniques.

  10. System Reliability for LED-Based Products

    SciTech Connect

    Davis, J Lynn; Mills, Karmann; Lamvik, Michael; Yaga, Robert; Shepherd, Sarah D; Bittle, James; Baldasaro, Nick; Solano, Eric; Bobashev, Georgiy; Johnson, Cortina; Evans, Amy

    2014-04-07

    Results from accelerated life tests (ALT) on mass-produced commercially available 6” downlights are reported along with results from commercial LEDs. The luminaires capture many of the design features found in modern luminaires. In general, a systems perspective is required to understand the reliability of these devices since LED failure is rare. In contrast, components such as drivers, lenses, and reflector are more likely to impact luminaire reliability than LEDs.

  11. LEDs for Efficient Energy

    ERIC Educational Resources Information Center

    Guerin, David A.

    1978-01-01

    Light-emitting diodes (LEDs) are described and three classroom experiments are given, one to prove the, low power requirements and efficiency of LEDs, an LED on-off detector circuit, and the third an LED photoelectric smoke detector. (BB)

  12. Simultaneous measurement of ventilation using tracer gas techniques and VOC concentrations in homes, garages and vehicles.

    PubMed

    Batterman, Stuart; Jia, Chunrong; Hatzivasilis, Gina; Godwin, Chris

    2006-02-01

    Air exchange rates and interzonal flows are critical ventilation parameters that affect thermal comfort, air migration, and contaminant exposure in buildings and other environments. This paper presents the development of an updated approach to measure these parameters using perfluorocarbon tracer (PFT) gases, the constant injection rate method, and adsorbent-based sampling of PFT concentrations. The design of miniature PFT sources using hexafluorotoluene and octafluorobenzene tracers, and the development and validation of an analytical GC/MS method for these tracers are described. We show that simultaneous deployment of sources and passive samplers, which is logistically advantageous, will not cause significant errors over multiday measurement periods in building, or over shorter periods in rapidly ventilated spaces like vehicle cabins. Measurement of the tracers over periods of hours to a week may be accomplished using active or passive samplers, and low method detection limits (<0.025 microg m(-3)) and high precisions (<10%) are easily achieved. The method obtains the effective air exchange rate (AER), which is relevant to characterizing long-term exposures, especially when ventilation rates are time-varying. In addition to measuring the PFT tracers, concentrations of other volatile organic compounds (VOCs) are simultaneously determined. Pilot tests in three environments (residence, garage, and vehicle cabin) demonstrate the utility of the method. The 4 day effective AER in the house was 0.20 h(-1), the 4 day AER in the attached garage was 0.80 h(-1), and 16% of the ventilation in the house migrated from the garage. The 5 h AER in a vehicle traveling at 100 km h(-1) under a low-to-medium vent condition was 92 h(-1), and this represents the highest speed test found in the literature. The method is attractive in that it simultaneously determines AERs, interzonal flows, and VOC concentrations over long and representative test periods. These measurements are

  13. Superfund record of decision (EPA Region 1): Town Garage Radio Beacon, Londonderry, NH. (First remedial action), September 1992. Final report

    SciTech Connect

    Not Available

    1992-09-30

    The Town Garage Radio Beacon, NH, site includes the Holton Circle residential development of 23 homes, a town garage area, and an undeveloped hillslope and wetlands area in Londonderry, New Hampshire. From 1940 to 1968, the area was owned by the Department of Defense (DOD), who reportedly used it as a radio beacon facility from 1940 to 1947. The ROD provides a final remedy for the contaminated onsite ground water. No further remedial actions are anticipated for the site. The primary contaminants affecting the ground water are VOCs; and metals, including chromium.

  14. Worksite environment physical activity and healthy food choices: measurement of the worksite food and physical activity environment at four metropolitan bus garages

    PubMed Central

    Shimotsu, Scott T; French, Simone A; Gerlach, Anne F; Hannan, Peter J

    2007-01-01

    Background The present research describes a measure of the worksite environment for food, physical activity and weight management. The worksite environment measure (WEM instrument) was developed for the Route H Study, a worksite environmental intervention for weight gain prevention in four metro transit bus garages in Minneapolis-St. Paul. Methods Two trained raters visited each of the four bus garages and independently completed the WEM. Food, physical activity and weight management-related items were observed and recorded on a structured form. Inter-rater reliability was computed at the item level using a simple percentage agreement. Results The WEM showed high inter-rater reliability for the number and presence of food-related items. All garages had vending machines, microwaves and refrigerators. Assessment of the physical activity environment yielded similar reliability for the number and presence/absence of fitness items. Each garage had a fitness room (average of 4.3 items of fitness equipment). All garages had at least one stationary bike and treadmill. Three garages had at least one weighing scale available. There were no designated walking areas inside or outside. There were on average < 1 food stores or restaurants within sight of each garage. Few vending machine food and beverage items met criteria for healthful choices (15% of the vending machine foods; 26% of the vending machine beverages). The garage environment was perceived to be not supportive of healthy food choices, physical activity and weight management; 52% reported that it was hard to get fruits and vegetables in the garages, and 62% agreed that it was hard to be physically active in the garages. Conclusion The WEM is a reliable measure of the worksite nutrition, physical activity, and weight management environment that can be used to assess changes in the work environment. PMID:17498308

  15. Arbitrary object localization and tracking via multiple-camera surveillance system embedded in a parking garage

    NASA Astrophysics Data System (ADS)

    Ibisch, André; Houben, Sebastian; Michael, Matthias; Kesten, Robert; Schuller, Florian

    2015-03-01

    We illustrate a multiple-camera surveillance system installed in a parking garage to detect arbitrary moving objects. Our system is real-time capable and computes precise and reliable object positions. These objects are tracked to warn of collisions, e.g. between vehicles, pedestrians or other vehicles. The proposed system is based on multiple grayscale cameras connected by a local area network. Each camera shares its field of view with other cameras to handle occlusions and to enable multi-view vision. We aim at using already installed hardware found in many modern public parking garages. The system's pipeline starts with the synchronized image capturing process separately for each camera. In the next step, moving objects are selected by a foreground segmentation approach. Subsequently, the foreground objects from a single camera are transformed into view rays in a common world coordinate system and are joined to receive plausible object hypotheses. This transformation requires a one-time initial intrinsic and extrinsic calibration beforehand. Afterwards, these view rays are filtered temporally to arrive at continuous object tracks. In our experiments we used a precise LIDAR-based reference system to evaluate and quantify the proposed system's precision with a mean localization accuracy of 0.24m for different scenarios.

  16. Concentrations and emissions of polybrominated diphenyl ethers from U.S. houses and garages.

    PubMed

    Batterman, Stuart A; Chernyak, Sergei; Jia, Chunrong; Godwin, Christopher; Charles, Simone

    2009-04-15

    Concentrations of polybrominated diphenyl ethers (PBDEs) and other brominated flame retardants (BFRs) have been rapidly increasing in fish, birds, sediments, indoor environments, and humans, but emission sources and exposure pathways of these pollutants remain poorly understood. The many BFR-containing materials in buildings constitute a large reservoir of these compounds, and in-use releases from this reservoir may be a significant environmental source. To estimate in-use releases from building materials and contents in residences, we monitored 12 houses and garages in two seasons and combined measurements of BFRs in air and settled dust, air exchange rates, and other information in an approach that utilized the building as a "natural" test chamber. Results were scaled to provide a first estimate of aggregate emission rates from U.S. houses. PBDE releases total about 4 microg h(-1) per house or 20 ng m(-2) h(-1), and U.S. houses and garages collectively release about 4100 kg y(-1). Most of these releases are settled floor dust, but about 20% are released directly to the ambient environment via airborne vapor and particulate matter. These screening-level estimates are subject to considerable uncertainty, but they have an advantage in that they reflect real-world conditions based on mass balance calculations. PMID:19475936

  17. A Case Study Exploring the Use of GarageBand[TM] and an Electronic Bulletin Board in Preservice Music Education

    ERIC Educational Resources Information Center

    Vratulis, Vetta; Morton, Charlene

    2011-01-01

    This qualitative research study is an exploration of the merit and shortcomings of using a combination of the music software GarageBand[TM] and an electronic bulletin board to facilitate musical and peer learning in a 3-month elementary music methods curriculum and instruction course. A pedagogical objective of this assignment was to increase the…

  18. Can We Afford These Affordances? GarageBand and the Double-Edged Sword of the Digital Audio Workstation

    ERIC Educational Resources Information Center

    Bell, Adam Patrick

    2015-01-01

    The proliferation of computers, tablets, and smartphones has resulted in digital audio workstations (DAWs) such as GarageBand in being some of the most widely distributed musical instruments. Positing that software designers are dictating the music education of DAW-dependent music-makers, I examine the fallacy that music-making applications such…

  19. Industrial scale garage-type dry fermentation of municipal solid waste to biogas.

    PubMed

    Qian, M Y; Li, R H; Li, J; Wedwitschka, H; Nelles, M; Stinner, W; Zhou, H J

    2016-10-01

    The objectives of this study was to through monitoring the 1st industrial scale garage-type dry fermentation (GTDF) MSW biogas plant in Bin County, Harbin City, Heilongjiang Province, China, to investigate its anaerobic digestion (AD) performance and the stability of process. After a monitoring period of 180days, the results showed that the volumetric biogas production of the digesters and percolate tank was 0.72 and 2.22m(3) (m(3)d)(-1), respectively, and the specific biogas yield of the feedstock was about 270m(3)CH4tVS(-1), which indicated that the GTDF is appropriate for the Chinese MSW. This paper also raised some problems aimed at improving the process stability and AD efficiency. PMID:26970693

  20. LED Color Characteristics

    SciTech Connect

    2012-01-01

    Color quality is an important consideration when evaluating LED-based products for general illumination. This fact sheet reviews the basics regarding light and color and summarizes the most important color issues related to white-light LED systems.

  1. LEDs in automotive lighting

    NASA Astrophysics Data System (ADS)

    Eichhorn, Karsten

    2006-02-01

    Light emitting diodes (LED) are becoming more and more significant in interior and exterior automotive lighting. The long service life, energy and space savings, shock and vibration resistance and new styling potential are the main advantages of using LEDs in automotive applications. Today, most central high mounted stop lamps use LEDs. In rear combination lamps the number of LEDs in amber and red is increasing rapidly. This year, a first rear combination lamp using LEDs for all functionalities including the back-up lamp function was realized. In addition, first signal functions in headlamps using white High Power LEDs were launched onto the market. The long service life characteristic makes LEDs especially predestined for the DRL function combined with the position/parking light. Exterior automotive applications, including requirements and performance will be discussed and an outlook will be given on future scenarios.

  2. Geohydrology and contamination at the Michigan Department of Transportation maintenance garage area, Kalamazoo County, Michigan

    USGS Publications Warehouse

    Lynch, E.A.; Huffman, G.C.

    1996-01-01

    A leaking underground storage tank was removed from the Michigan Department of Transportation maintenance garage area in Kalamazoo County., Mich., in 1985. The tank had been leaking unleaded gasoline. Although a remediation system was operational at the site for several years after the tank was removed, ground-water samples collected from monitoring wells in the area consistently showed high concentrations of benzene, toluene. ethylbenzene, and xylenes--indicators of the presence of gasoline. The U.S. Geological Survey did a study in cooperation with the Michigan Department of Transportation, to define the geology, hydrology, and occurrence of gasoline contamination in the maintenance garage area. The aquifer affected by gasoline contamination is an unconfined glaci'a.l sand and gravel aquifer. The average depth to water in the study area is about 74.7 feet. Water-level fluctuations are small; maximum fluctuation was slightly more than 1 foot during August 1993-August 1994. Hydraulic conductivities based on aquifer-test data collected for the study and estimated by use of the Cooper-Jacob method of solution ranged from 130 to 144 feet per day. Ground water is moving in an east-southeasterly direction at a rate of about I foot per day. Leakage from perforated pipes leading from the underground storage tanks to the pump station was identified as a second source of gasoline contamination to saturated and unsaturated zones. The existence of this previously unknown second source is part of the reason that previous remediation efforts were ineffective. Residual contaminants in the unsaturated zone are expected to continue to move to the water table with recharge, except in a small area covered by asphalt at the land surface. The gasoline plume from the perforated pipe source has merged with that from the leaking underground storage tank, and the combined plume in the saturated zone is estimated to cover an area of 30,000 square feet. The combined plume is in the upper 20

  3. Complementary LED technologies

    NASA Astrophysics Data System (ADS)

    Reineke, Sebastian

    2015-05-01

    Organic semiconducting molecules and colloidal quantum dots both make for excellent luminescent materials. Compared with the more established solid-state light-emitting technologies, organic LEDs and quantum-dot LEDs are in their infancy, yet they offer unique properties.

  4. Diodes stabilize LED output

    NASA Technical Reports Server (NTRS)

    Deters, R. A.

    1977-01-01

    Small-signal diodes are placed in series with light-emitting diodes (LED's) to stabilize LED output against temperature fluctuations. Simple inexpensive method compensates for thermal fluctuations over a broad temperature range. Requiring few components, technique is particularly useful where circuit-board space is limited.

  5. Large area LED package

    NASA Astrophysics Data System (ADS)

    Goullon, L.; Jordan, R.; Braun, T.; Bauer, J.; Becker, F.; Hutter, M.; Schneider-Ramelow, M.; Lang, K.-D.

    2015-03-01

    Solid state lighting using LED-dies is a rapidly growing market. LED-dies with the needed increasing luminous flux per chip area produce a lot of heat. Therefore an appropriate thermal management is required for general lighting with LEDdies. One way to avoid overheating and shorter lifetime is the use of many small LED-dies on a large area heat sink (down to 70 μm edge length), so that heat can spread into a large area while at the same time light also appears on a larger area. The handling with such small LED-dies is very difficult because they are too small to be picked with common equipment. Therefore a new concept called collective transfer bonding using a temporary carrier chip was developed. A further benefit of this new technology is the high precision assembly as well as the plane parallel assembly of the LED-dies which is necessary for wire bonding. It has been shown that hundred functional LED-dies were transferred and soldered at the same time. After the assembly a cost effective established PCB-technology was applied to produce a large-area light source consisting of many small LED-dies and electrically connected on a PCB-substrate. The top contacts of the LED-dies were realized by laminating an adhesive copper sheet followed by LDI structuring as known from PCB-via-technology. This assembly can be completed by adding converting and light forming optical elements. In summary two technologies based on standard SMD and PCB technology have been developed for panel level LED packaging up to 610x 457 mm2 area size.

  6. Development of lighting system for hologram using high power LEDs

    NASA Astrophysics Data System (ADS)

    Baba, Junko; Yaeda, Asami; Asakawa, Hisashi; Shibuya, Takehisa; Wakaki, Moriaki

    2007-02-01

    Light emitting diode (LED) became popular rapidly by the appearance of blue LED. Three color (R, G, B) emitting LEDs are utilized for the image display system by the development of multi color emitting LED. White LEDs became to commercial base by combining blue or UV light sources for excitation and materials for fluorescence. White LEDs are prevailing for general lighting applications. A single tip with the power of 5W became line up for commercial market owing to the research for high intensity LEDs. As a result, LEDs are replacing the market of conventional incandescent lighting and even head lights of the automobile. In this study, we aim to fabricate the white and R, G, B lighting system using high brightness LEDs for the lighting of holograms instead of a conventional halogen lamp.

  7. LEDs Are Diodes.

    ERIC Educational Resources Information Center

    Lisensky, George C.; Condren, S. Michael; Widstrand, Cynthia G.; Breitzer, Jonathan; Ellis, Arthur B.

    2001-01-01

    Describes an activity comparing incandescent bulbs and LEDs powered by dc and ac voltage sources to illustrate properties of matter and the interactions of energy and matter. Includes both instructor information and student activity sheet. (Author/YDS)

  8. White LED performance

    NASA Astrophysics Data System (ADS)

    Gu, Yimin; Narendran, Nadarajah; Freyssinier, Jean Paul

    2004-10-01

    Two life tests were conducted to compare the effects of drive current and ambient temperature on the degradation rate of 5 mm and high-flux white LEDs. Tests of 5 mm white LED arrays showed that junction temperature increases produced by drive current had a greater effect on the rate of light output degradation than junction temperature increases from ambient heat. A preliminary test of high-flux white LEDs showed the opposite effect, with junction temperature increases from ambient heat leading to a faster depreciation. However, a second life test is necessary to verify this finding. The dissimilarity in temperature effect among 5 mm and high-flux LEDs is likely caused by packaging differences between the two device types.

  9. Energy Efficiency of LEDs

    SciTech Connect

    2013-03-01

    Solid-state lighting program technology fact sheet on energy efficiency of LEDs, characterizing the current state of the market and discussing package efficacy, luminaire efficacy, and application efficacy.

  10. LED applications in biomedicine

    NASA Astrophysics Data System (ADS)

    Liu, Timon C.; Huang, Ping; Liu, Jiang; Yin, Jian-Ling; Fan, Guang-Han; Liu, Song-Hao

    2003-12-01

    Light-emitting diode (LED) technology has provided medicine with a new tool capable of delivering light deep into tissues of the body, at wavelengths which are biologically optimal for cancer treatment, wound healing and other clinical applications. In this paper, a simple review on the clinical use in therapeutic applications as well as in laboratory work of LEDs is given in view of low intensity laser irradiation effects in biomedicine.

  11. Deep UV LEDs

    NASA Astrophysics Data System (ADS)

    Han, Jung; Amano, Hiroshi; Schowalter, Leo

    2014-06-01

    Deep ultraviolet (DUV) photons interact strongly with a broad range of chemical and biological molecules; compact DUV light sources could enable a wide range of applications in chemi/bio-sensing, sterilization, agriculture, and industrial curing. The much shorter wavelength also results in useful characteristics related to optical diffraction (for lithography) and scattering (non-line-of-sight communication). The family of III-N (AlGaInN) compound semiconductors offers a tunable energy gap from infrared to DUV. While InGaN-based blue light emitters have been the primary focus for the obvious application of solid state lighting, there is a growing interest in the development of efficient UV and DUV light-emitting devices. In the past few years we have witnessed an increasing investment from both government and industry sectors to further the state of DUV light-emitting devices. The contributions in Semiconductor Science and Technology 's special issue on DUV devices provide an up-to-date snapshot covering many relevant topics in this field. Given the expected importance of bulk AlN substrate in DUV technology, we are pleased to include a review article by Hartmann et al on the growth of AlN bulk crystal by physical vapour transport. The issue of polarization field within the deep ultraviolet LEDs is examined in the article by Braut et al. Several commercial companies provide useful updates in their development of DUV emitters, including Nichia (Fujioka et al ), Nitride Semiconductors (Muramoto et al ) and Sensor Electronic Technology (Shatalov et al ). We believe these articles will provide an excellent overview of the state of technology. The growth of AlGaN heterostructures by molecular beam epitaxy, in contrast to the common organo-metallic vapour phase epitaxy, is discussed by Ivanov et al. Since hexagonal boron nitride (BN) has received much attention as both a UV and a two-dimensional electronic material, we believe it serves readers well to include the

  12. LED flicker pulsing

    NASA Astrophysics Data System (ADS)

    Johnson, Mark A.; Cote, Paul J.

    2001-08-01

    There is need to replace hazardous radioluminescent light sources with a means of illumination that is environmentally friendly. This paper describes an electronic source that was developed as a potential candidate to replace low intensity tritium in a military system. It employs an LED for illumination and a 3-volt coin cell battery as a power source. This new light source is electronically invisible, requires minimal maintenance, and provides the lowest practical illumination to preclude detection by optical means. The low intensity requires that the LED be driven at DC current levels resulting in poor luminous efficiency. Therefore, in an effort to maximize battery life, the LED is pulsed into a more optically efficient mode of operation. However, conventional pulsing techniques are not employed because of concerns the electronics could be identified by conspicuous power spectral density (PSD) components in the electromagnetic spectrum generated by a pulsed LED. Therefore, flicker noise concepts have been employed to efficiently drive the LED while generating a virtually undetectable spectral signature. Although ideally the pulse durations, magnitudes, and spacings should be random, a significant reduction in conspicuous PSD components can be achieved when imposing practical constraints. The dominant components of the power spectrum are significantly reduced using fixed pulse durations and magnitudes while varying only the pulse spacing. The mean duty cycle is set to provide the same effective illumination as DC operation while generating a PSD normally associated with natural phenomena.

  13. Increased Efficiency LED

    NASA Technical Reports Server (NTRS)

    Egalon, Claudio O. (Inventor); Rogowski, Robert S. (Inventor)

    1998-01-01

    In an LED a large portion of the light produced is lost due to total internal reflection at the air-semiconductor interface. A reverse taper of the semiconductor is used to change the angle at which light strikes the interface so that a greater portion of the light is transmitted.

  14. Nurse-led discharge.

    PubMed

    Page, Carole

    2010-12-01

    Delayed discharges have financial implications for hospital trusts and cause dissatisfaction for patients and their families. This article looks at nurse-led discharge pathways at Milton Keynes Hospital's ambulatory care unit. It explains how giving nurses the responsibility to discharge has improved the patient experience, made nurses more accountable and saved money for the trust. PMID:21229868

  15. Comparative Assessment of Blood Lead Levels of Automobile Technicians in Organised and Roadside Garages in Lagos, Nigeria

    PubMed Central

    Saliu, Abdulsalam; Adebayo, Onajole; Kofoworola, Odeyemi; Babatunde, Ogunowo; Ismail, Abdussalam

    2015-01-01

    Occupational exposure to lead is common among automobile technicians and constitutes 0.9% of total global health burden with a majority of cases in developing countries. The aim of this study was to determine and compare the blood lead levels of automobile technicians in roadside and organised garages in Lagos State, Nigeria. This was a comparative cross-sectional study. Data were collected using interviewer-administered questionnaires. Physical examinations were conducted and blood was analysed for lead using atomic spectrophotometery. Statistical analyses were performed to compare the median blood lead levels of each group using the independent sample (Mann-Whitney U) test. Seventy-three (40.3%) of the organised compared to 59 (34.3%) of the roadside groups had high blood lead levels. The organised group had statistically significant higher median blood lead levels of, 66.0 µg/dL than the roadside 43.5 µg/dL (P < 0.05). There was also statistically significant association between high blood lead levels and abnormal discolouration of the mucosa of the mouth in the organised group. Automobile technicians in organised garages in Lagos have higher prevalence of elevated blood lead levels and higher median levels than the roadside group. Preventive strategies against lead exposures should be instituted by the employers and further actions should be taken to minimize exposures, improve work practices, implement engineering controls (e.g., proper ventilation), and ensure the use of personal protective equipment. PMID:25759723

  16. Epidemiological-environmental study of diesel bus garage workers: chronic effects of diesel exhaust on the respiratory system

    SciTech Connect

    Gamble, J.; Jones, W.; Minshall, S.

    1987-10-01

    Two hundred and eighty-three (283) male diesel bus garage workers from four garages in two cities were examined to determine if there was excess chronic respiratory morbidity related to diesel exposure. The dependent variables were respiratory symptoms, radiographic interpretation for pneumoconiosis, and pulmonary function (FVC, FEV1, and flow rates). Independent variables included race, age, smoking, drinking, height, and tenure (as surrogate measure of exposure). Exposure-effect relationships within the study population showed no detectable associations of symptoms with tenure. There was an apparent association of pulmonary function and tenure. Seven workers (2.5%) had category 1 pneumoconiosis (three rounded opacities, two irregular opacities, and one with both rounded and irregular). The study population was also compared to a nonexposed blue-collar population. After indirect adjustment for age, race, and smoking, the study population had elevated prevalences of cough, phlegm, and wheezing, but there was no association with tenure. Dyspnea showed a dose-response trend but no apparent increase in prevalence. Mean percent predicted pulmonary function of the study population was greater than 100%, i.e., elevated above the comparison population. These data show there is an apparent effect of diesel exhaust on pulmonary function but not chest radiographs. Respiratory symptoms are high compared to blue-collar workers, but there is no relationship with tenure.

  17. Design of Knight LED system

    NASA Astrophysics Data System (ADS)

    Zheng, Wen; Lou, Yuna; Xiao, Zhihong

    2010-02-01

    This design introduces a used car on the design of LED decorative light strip. This LED named Knight LED. In This system we use ATMEGA8 as the Master MCU Chip. Through the microcontroller to implement the wireless remote control receiver and the LED lights of different modes of switching, different brightness control. Also we use ULN2803 as the LED driver.

  18. High Power UV LED Industrial Curing Systems

    SciTech Connect

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

    2012-05-14

    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.

  19. LEDs in frequency-omain spectroscopy of tissues

    NASA Astrophysics Data System (ADS)

    Franceschini, Maria-Angela; Fantini, Sergio; Gratton, Enrico

    1994-05-01

    Light spectroscopy in the frequency-domain has been used to study the optical properties of biological tissues. We have analyzed the possibility of using LEDs as intensity modulated light sources for frequency-domain spectroscopy. The use of LEDs presents several advantages: one LED's output covers a spectral region of about 80 nm, and commercially available LEDs allow for the coverage of the spectral range from 550 to 900 nm, which is a region of interest in near-IR medical applications; the light output of an LED is stable with respect to that of lasers and lamps; the wide angular distribution make LEDs safe for in vivo studies. Furthermore, LED frequency-domain spectroscopy is a relatively inexpensive technique. We describe some circuits we used to modulate the intensity of LEDs at radio frequency, and point out the possibility of building a multisource spectrometer. Some applications of LED frequency-domain spectroscopy, both in vitro and in vivo, are shown.

  20. Organic LED system applications

    NASA Astrophysics Data System (ADS)

    Cropper, A. D.; Cok, Ronald S.; Feldman, Rodney D.

    2001-02-01

    Organic LED (OLED) technology promises superior performance in brightness and color resolution, wider viewing angles, lower power consumption, thin displays, and robust physical characteristics. These advantages make OLED displays attractive for next-generation flat panel displays. This paper describes the state-of-the-art in OLED technology and addresses some of the benefits and difficulties facing the integration of OLED devices into a range of imaging equipment applications. We will review OLED performance from a systems perspective and will compare it to OLED material and panel properties. We will also describe the competitive attributes of a flat panel display and recent work done at Kodak on interfacing to OLED devices.

  1. Germanium-on-InP heterojunction-structure LED

    NASA Technical Reports Server (NTRS)

    Hawrylo, F. Z.

    1980-01-01

    Ge-on-InP heterojunction structure LED has been developed where in Ge film is evaporated onto commercially available InP substrate. Forward bias of device is approximately 1 volt, and it emits light in 9.800 angstrom region. Technique permits easy and inexpensive fabrication of LED for application at this wavelength.

  2. White LED with High Package Extraction Efficiency

    SciTech Connect

    Yi Zheng; Matthew Stough

    2008-09-30

    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

  3. High-luminance LEDs replace incandescent lamps in new applications

    NASA Astrophysics Data System (ADS)

    Evans, David L.

    1997-04-01

    The advent of high luminance AlInGaP and InGaN LED technologies has prompted the use of LED devices in new applications formally illuminated by incandescent lamps. The luminous efficiencies of these new LED technologies equals or exceeds that attainable with incandescent sources, with reliability factors that far exceed those of incandescent sources. The need for a highly efficient, dependable, and cost effective replacement for incandescent lamps is being fulfilled with high luminance LED lamps. This paper briefly described some of the new applications incorporating high luminance LED lamps, traffic signals and roadway signs for traffic management, automotive exterior lighting, active matrix and full color displays for commercial advertising, and commercial aircraft panel lighting and military aircraft NVG compatible lighting.

  4. CALiPER Benchmark Report: Performance of Incandescent A Type and Decorative Lamps and LED Replacements

    SciTech Connect

    Lingard, R. D.; Myer, M. A.; Paget, M. L.

    2008-11-01

    This benchmark report addresses common omnidirectional incandescent lamps - A-type and small decorative, candelabra-type lamps - and their commercially available light-emitting diode (LED) replacements.

  5. LED Device Illuminates New Path to Healing

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Among NASA s research goals is increased understanding of factors affecting plant growth, including the effects of microgravity. Impeding such studies, traditional light sources used to grow plants on Earth are difficult to adapt to space flight, as they require considerable amounts of power and produce relatively large amounts of heat. As such, an optimized experimental system requires much less energy and reduces temperature variance without negatively affecting plant growth results. Ronald W. Ignatius, founder and chairman of the board at Quantum Devices Inc. (QDI), of Barneveld, Wisconsin, proposed using light-emitting diodes (LEDs) as the photon source for plant growth experiments in space. This proposition was made at a meeting held by the Wisconsin Center for Space Automation and Robotics, a NASA-sponsored research center that facilitates the commercialization of robotics, automation, and other advanced technologies. The Wisconsin group teamed with QDI to determine whether an LED system could provide the necessary wavelengths and intensities for photosynthesis, and the resultant system proved successful. The center then produced the Astroculture3, a plant growth chamber that successfully incorporated this LED light source, which has now flown on several space shuttle missions. NASA subsequently identified another need that could be addressed with the use of LEDs: astronaut health. A central concern in astronaut health is maintaining healthy growth of cells, including preventing bone and muscle loss and boosting the body s ability to heal wounds all adversely affected by prolonged weightlessness. Thus, having determined that LEDs can be used to grow plants in space, NASA decided to investigate whether LEDs might be used for photobiomodulation therapy (PBMT).

  6. High-power LEDs for plant cultivation

    NASA Astrophysics Data System (ADS)

    Tamulaitis, Gintautas; Duchovskis, Pavelas; Bliznikas, Zenius; Breive, Kestutis; Ulinskaite, Raimonda; Brazaityte, Ausra; Novickovas, Algirdas; Zukauskas, Arturas; Shur, Michael S.

    2004-10-01

    We report on high-power solid-state lighting facility for cultivation of greenhouse vegetables and on the results of the study of control of photosynthetic activity and growth morphology of radish and lettuce imposed by variation of the spectral composition of illumination. Experimental lighting modules (useful area of 0.22 m2) were designed based on 4 types of high-power light-emitting diodes (LEDs) with emission peaked in red at the wavelengths of 660 nm and 640 nm (predominantly absorbed by chlorophyll a and b for photosynthesis, respectively), in blue at 455 nm (phototropic function), and in far-red at 735 nm (important for photomorphology). Morphological characteristics, chlorophyll and phytohormone concentrations in radish and lettuce grown in phytotron chambers under lighting with different spectral composition of the LED-based illuminator and under illumination by high pressure sodium lamps with an equivalent photosynthetic photon flux density were compared. A well-balanced solid-state lighting was found to enhance production of green mass and to ensure healthy morphogenesis of plants compared to those grown using conventional lighting. We observed that the plant morphology and concentrations of morphologically active phytohormones is strongly affected by the spectral composition of light in the red region. Commercial application of the LED-based illumination for large-scale plant cultivation is discussed. This technology is favorable from the point of view of energy consumption, controllable growth, and food safety but is hindered by high cost of the LEDs. Large scale manufacturing of high-power red AlInGaP-based LEDs emitting at 650 nm and a further decrease of the photon price for the LEDs emitting in the vicinity of the absorption peak of chlorophylls have to be achieved to promote horticulture applications.

  7. LED pumped polymer laser sensor for explosives

    PubMed Central

    Wang, Yue; Morawska, Paulina O; Kanibolotsky, Alexander L; Skabara, Peter J; Turnbull, Graham A; Samuel, Ifor D W

    2013-01-01

    A very compact explosive vapor sensor is demonstrated based on a distributed feedback polymer laser pumped by a commercial InGaN light-emitting diode. The laser shows a two-stage turn on of the laser emission, for pulsed drive currents above 15.7 A. The ‘double-threshold’ phenomenon is attributed to the slow rise of the ∼30 ns duration LED pump pulses. The laser emits a 533 nm pulsed output beam of ∼10 ns duration perpendicular to the polymer film. When exposed to nitroaromatic model explosive vapors at ∼8 ppb concentration, the laser shows a 46% change in the surface-emitted output under optimized LED excitation. PMID:25821526

  8. Comparison of different LED Packages

    NASA Astrophysics Data System (ADS)

    Dieker, Henning; Miesner, Christian; Püttjer, Dirk; Bachl, Bernhard

    2007-09-01

    In this paper different technologies for LED packaging are compared, focusing on Chip on Board (COB) and SMD technology. The package technology which is used depends on the LED application. A critical fact in LED technology is the thermal management, especially for high brightness LED applications because the thermal management is important for reliability, lifetime and electrooptical performance of the LED module. To design certain and long life LED applications knowledge of the heat flow from LEDs to the complete application is required. High sophisticated FEM simulations are indispensable for modern development of high power LED applications. We compare simulations of various substrate materials and packaging technologies simulated using FLOTHERM software. Thereby different substrates such as standard FR4, ceramic and metal core printed circuit boards are considered. For the verification of the simulated results and the testing of manufactured modules, advanced measurement tools are required. We show different ways to experimentally characterize the thermal behavior of LED modules. The thermal path is determined by the transient thermal analysis using the MicReD T3Ster analyzer. Afterwards it will be compared to the conventional method using thermocouples. The heat distribution over the module is investigated by an IR-Camera. We demonstrate and compare simulation and measurement results of Chip-on-Board (COB) and Sub-Mounted Devices (SMD) technology. The results reveal that for different applications certain packages are ideal.

  9. Nobel Prize for blue LEDs

    NASA Astrophysics Data System (ADS)

    Kraftmakher, Yaakov

    2015-05-01

    A brief review of lighting technologies is presented. Unavoidable restrictions for incandescent light bulbs caused by the Planck distribution and properties of the human eye are illustrated. The efficiency and luminous efficacy of thermal radiation are calculated for various temperatures; the results clearly show the limitations for thermal radiators. The only way to overcome these limitations is using non-thermal radiators, such as fluorescent lamps and light-emitting diodes (LEDs). Unique advantages of LEDs undoubtedly made a revolution in this field. A crucial element of this progress is the blue LEDs (Nobel Prize 2014). Some experiments with a blue and a green LED are described: (i) the luminescence triggered in a green-yellow phosphor inside a white LED by the blue LED; (ii) radiant spectra and ‘efficiency droop’ in the LEDs; (iii) modulation of the blue LED up to 4 MHz; and (iv) the h/e ratio from the turn-on voltage of the green LED. The experiments are suitable for undergraduate laboratories and usable as classroom demonstrations.

  10. Air quality in urban parking garages (PM10, major and trace elements, PAHs): Instrumental measurements vs. active moss biomonitoring

    NASA Astrophysics Data System (ADS)

    Vuković, Gordana; Aničić Urošević, Mira; Razumenić, Ivana; Kuzmanoski, Maja; Pergal, Miodrag; Škrivanj, Sandra; Popović, Aleksandar

    2014-03-01

    This study was performed in four parking garages in downtown of Belgrade with the aim to provide multi-pollutant assessment. Concentrations of 16 US EPA priority PAHs and Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sr and Zn were determined in PM10 samples. The carcinogenic health risk of employees' occupational exposure to heavy metals (Cd, Cr, Ni and Pb) and PAHs (B[a]A, Cry, B[b]F, B[k]F, B[a]P and DB[ah]A) was estimated. A possibility of using Sphagnum girgensohnii moss bags for monitoring of trace element air pollution in semi-enclosed spaces was evaluated as well. The results showed that concentrations of PM10, Cd, Ni and B[a]P exceeded the EU Directive target values. Concentration of Zn, Ba and Cu were two orders of magnitude higher than those measured at different urban sites in European cities. Cumulative cancer risk obtained for heavy metals and PAHs was 4.51 × 10-5 and 3.75 × 10-5 in M and PP, respectively; upper limit of the acceptable US EPA range is 10-4. In the moss, higher post-exposure than pre-exposure (background) element concentrations was observed. In comparison with instrumental monitoring data, similar order of abundances of the most elements in PM10 and moss samples was found. However, using of the S. girgensohnii moss bag technique in indoor environments needs further justification.

  11. Advanced poly-LED displays

    NASA Astrophysics Data System (ADS)

    Childs, Mark; Nisato, Giovanni; Fish, D.; Giraldo, Andrea; Jenkins, A. J.; Johnson, Mark T.

    2003-05-01

    Philips have been actively developing polymer OLED (poly-LED) displays as a future display technology. Their emissive nature leads to a very attractive visual appearance, with wide viewing angle, high brightness and fast response speed. Whilst the first generation of poly-LED displays are likely to be passive-matrix driven, power reduction and resolution increase will lead to the use of active-matrix poly-LED displays. Philips Research have designed, fabricated and characterized five different designs of active-matrix polymer-LED display. Each of the five displays makes use of a distinct pixel programming- or pixel drive-technique, including current programming, threshold voltage measurement and photodiode feedback. It will be shown that hte simplest voltage-programmed current-source pixel suffers from potentially unacceptable brightness non-uniformity, and that advanced pixel circuits can provide a solution to this. Optical-feedback pixel circuits will be discussed, showing that they can be used to improve uniformity and compensate for image burn-in due to polymer-LED material degradation, improving display lifetime. Philips research has also been active in developing technologies required to implement poly-LED displays on flexible substrates, including materials, processing and testing methods. The fabrication of flexible passive-matrix poly-LED displays will be presented, as well as the ongoing work to assess the suitability of processing flexible next-generation poly-LED displays.

  12. High CRI phosphor blends for near-UV LED lamps

    NASA Astrophysics Data System (ADS)

    Radkov, Emil; Setlur, Anant; Brown, Zena; Reginelli, James

    2004-10-01

    Currently, the highest color rendering index (CRI) value obtained in commercially available LED devices is around 90. This falls short of the CRI values typical for incandescent lamps (defined at 100). Similarly, the commercially available LEDs for higher color temperature have CRI values of 65-85, well below the theoretical maximum of 100. New phosphor blends are proposed for use with LED chips emitting in the 350-450 nm range. The application of such blends can afford CRI values greater than 95, over the entire range of color temperatures of interest for general illumination (2500K - 8000K). In some cases, the CRI values approach the theoretical maximum of 100. LED based lamps with a steady state performance of 23 LPW and 25 lumens per chip at 3000K, with a general CRI (Ra) of 97 and a mean CRI (R1-R14) of 96 are demonstrated.

  13. LEDs Illuminate Bulbs for Better Sleep, Wake Cycles

    NASA Technical Reports Server (NTRS)

    2015-01-01

    Life on the International Space Station (ISS) wreaks havoc on an astronaut’s biological rhythms, and one way NASA mitigates the problem is through the use of LED lighting to alternately stimulate energy and focus and induce relaxation. Satellite Beach, Florida-based Lighting Science partnered with Kennedy Space Center to commercialize an LED system designed for the ISS, resulting in its DefinityDigital product line of light bulbs now used in numerous homes, hotel chains, and resorts.

  14. Metacapacitors for LED Lighting: Metacapacitors

    SciTech Connect

    2010-09-02

    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. ZnSe-based white LEDs

    NASA Astrophysics Data System (ADS)

    Katayama, K.; Matsubara, H.; Nakanishi, F.; Nakamura, T.; Doi, H.; Saegusa, A.; Mitsui, T.; Matsuoka, T.; Irikura, M.; Takebe, T.; Nishine, S.; Shirakawa, T.

    2000-06-01

    The first phosphor-free white LED based on II-IV compound materials is demonstrated. Our device utilizes a phenomenon unique to ZnSe homoepitaxy, where a portion of the main greenish-blue emission from the active layer of a pn junction diode is absorbed by the conductive substrate which in turn gives off an intense broad-band yellow emission centered around 585 nm by photoluminescence. These two emission bands combine to give a spectrum which appears white to the naked eye. A typical ZnSe-based white LED lamp exhibits a color temperature of approximately 3400 K with a CRI (color rendering index) of 68. The optical output power and operating voltage of such a device at a forward current of 20 mA is 2.0 mW and 2.7 V, respectively. The luminous efficiency estimated from these results is 10.4l m/W, which is comparable to the incandescent lamp as well as the commercial InGaN-based white LED. Device lifetimes (half-life) have exceeded 800 h at 20°C.

  16. Light pipes for LED measurements

    NASA Technical Reports Server (NTRS)

    Floyd, S. R.; Thomas, E. F., Jr.

    1976-01-01

    Light pipe directly couples LED optical output to single detector. Small area detector measures total optical output of diode. Technique eliminates thermal measurement problems and channels optical output to remote detector.

  17. [Light-emitting diodes (LED)].

    PubMed

    Cartier, H; Le Pillouer-Prost, A; Grognard, C

    2009-10-01

    LED home-use is now widely spread. In dermatology, numerous reports have stated their results for many indications: wound healing process, rejuvenation, acne and, of course, photodynamic therapy. Nevertheless, fluence, pulse duration and color of the LED are so variable as it is difficult to bring well codified results. But how should you not be interested in this field? It is already any more a near future but well and truly a therapeutic reality... PMID:19931696

  18. High performance RGB LED backlight in high temperature environment

    NASA Astrophysics Data System (ADS)

    Grabski, Grzegorz; Gurr, Walter; Green, John

    2008-04-01

    The Aerospace and Defense display industry is in the midst of converting light the sources used in AMLCD backlighting technology from fluorescent lamps to LEDs. Although challenging, the fluorescent backlighting technology delivered good product in high end applications. LEDs, however, have the promise of even greater efficiency and lower cost. The history of LED backlighting is short and very dynamic; expectations are high and promises are many. It appears that for engineers developing backlights for high performance displays life has not become easier with the change of the technology. This paper will discuss just one of many challenges engineer's face: operation of LED backlights in high temperature environments. It will present experimental data showing several advantages of the RGB LED technology over other lamp technologies for high performance commercial and military application.

  19. Effects of Cryogenic Temperatures on LEDs and Optical Fiber

    NASA Technical Reports Server (NTRS)

    Pantel, Erica R.

    2005-01-01

    Light Emitting Diodes (LEDs) may provide a simple, low powered light source for future space missions. However, the effects of cryogenic temperatures on LEDs and optical fibers are largely unknown. Tests were performed on a selection of commercially-available LEDs, with wavelengths varying from 468 nm to 950 nm, as well as "white" LEDs. Dry ice and liquid nitrogen (LN2) were used to bring the LEDs to the desired temperatures. The optical fibers were tested using a specially-machined brass cylinder that would allow the fibers to be cooled slowly and evenly in an LN2 dewer. An optical fiber coupled to a spectrometer was used to acquired spectra of a calibration light source (wavelength range 253-922 nm) at various temperatures. Examination of the LED spectra has shown several different effects, depending on the LED in question. Those with wavelengths above 590 nm tend to show a "blue shift" in their peak wavelength and an increase in intensity. Other LEDs developed secondary or tertiary peaks, or showed no peak shift at all, although all LEDs did show an increase in observed intensity. The optical fiber showed a slight non-uniform decrease in transmission as the temperature cooled to -195 C.

  20. Low-Cost Illumination-Grade LEDs

    SciTech Connect

    Epler, John

    2013-08-31

    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.

  1. Optical characterization of ultrabright LEDs

    SciTech Connect

    Benavides, Juan Manuel; Webb, Robert H

    2005-07-01

    Ultrabright light emitting diodes (LEDs) are a new light source for visual psychophysics and microscopy. The new LEDs are intended primarily for room and exterior illumination, and the manufacturers' specifications are adequate for that. However, we use them as light sources in situations where a more complete characterization may be useful. For one set of LEDs we have measured the radiometric intensity and its distribution in space and wavelength, and we have tested for interactions of these variables and their dependence on driver configuration. We describe techniques for making these measurements and give a link to a simple calculator for converting among radiometric and photometric measures, as well as an evaluation of the safety considerations these very bright sources demand.

  2. Commercial Crew

    NASA Video Gallery

    Phil McAlister delivers a presentation by the Commercial Crew (CC) study team on May 25, 2010, at the NASA Exploration Enterprise Workshop held in Galveston, TX. The purpose of this workshop was to...

  3. Site-specific standard request for Underground Storage Tanks 1219-U, 1222-U, 2082-U, and 2068-U at the Rust Garage Facility Buildings 9754-1 and 9720-15

    SciTech Connect

    Not Available

    1994-08-01

    This document is a site-specific standard request for underground storage tanks located at the Rust Garage Facility. These standards are justified based on conclusion derived from the exposure assessment that indicates there is no current or forseeable future human health risk associated with petroleum contaminants on the site, that current and future ecological risks would be generally limited to subsurface species and plant life with roots extending into the area, and that most of the impacted area at the site is covered by asphalt or concrete. The vertical and horizontal extent of soil and ground water contamination are limited to immediate area of the Rust Garage Facility.

  4. Space Commercialization

    NASA Technical Reports Server (NTRS)

    Martin, Gary L.

    2011-01-01

    A robust and competitive commercial space sector is vital to continued progress in space. The United States is committed to encouraging and facilitating the growth of a U.S. commercial space sector that supports U.S. needs, is globally competitive, and advances U.S. leadership in the generation of new markets and innovation-driven entrepreneurship. Energize competitive domestic industries to participate in global markets and advance the development of: satellite manufacturing; satellite-based services; space launch; terrestrial applications; and increased entrepreneurship. Purchase and use commercial space capabilities and services to the maximum practical extent Actively explore the use of inventive, nontraditional arrangements for acquiring commercial space goods and services to meet United States Government requirements, including measures such as public-private partnerships, . Refrain from conducting United States Government space activities that preclude, discourage, or compete with U.S. commercial space activities. Pursue potential opportunities for transferring routine, operational space functions to the commercial space sector where beneficial and cost-effective.

  5. White LED motorcycle headlamp design

    NASA Astrophysics Data System (ADS)

    Sun, Wen-Shing

    2015-09-01

    The motorcycle headlamp is composed of a white LED module, an elliptical reflector, a parabolic reflector and a toric lens. We use non-sequential ray to improve the optical efficiency of the compound reflectors. Using the toric lens can meet ECE_113 regulation and obtain a good uniformity.

  6. Multicolor, High Efficiency, Nanotextured LEDs

    SciTech Connect

    Jung Han; Arto Nurmikko

    2011-09-30

    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.

  7. LED lamp power management system and method

    DOEpatents

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

    2013-03-19

    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.

  8. LED lamp color control system and method

    SciTech Connect

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

    2013-02-05

    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.

  9. LED Chips and Packaging for 120 LPW SSL Component

    SciTech Connect

    Ibbetson, James

    2009-12-28

    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) 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.

  10. Epidemiological-environmental study of diesel bus garage workers: acute effects of NO/sub 2/ and respirable particulate on the respiratory system

    SciTech Connect

    Gamble, J.; Jones, W.; Minshall, S.

    1987-02-01

    Personal samples of nitrogen dioxide (NO/sub 2/) and respirable particulate (RP) were collected over the shift on 232 workers in four diesel bus garages. Response was assessed by an acute respiratory questionnaire and before and after shift spirometry. Measures of exposure to NO/sub 2/ and RP were associated with work-related symptoms of cough; itching, burning, or watering eyes; difficult or labored breathing; chest tightness; and wheeze. The prevalence of burning eyes, headaches, difficult or labored breathing, nausea, and wheeze experienced at work were higher in the diesel bus garage workers than in a comparison population of battery workers, while the prevalence of headaches was reduced. Mean reductions in forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1), peak flow, and flows at 50 and 75% of FVC were not obviously different from zero. There was no detectable association of exposure to NO/sub 2/ or respirable particulate and acute reductions in pulmonary function. Workers who often had respiratory work-related symptoms generally had a slightly greater mean acute reduction in FEV1 and FEF50 than did those who did not have these symptoms, but these differences were not statistically significant.

  11. An Inexpensive LED Light Sensor

    ERIC Educational Resources Information Center

    Kutzner, Mickey; Wright, Richard; Kutzner, Emily

    2010-01-01

    Light irradiance measurements are important for students grappling with abstract optical phenomena such as the inverse square law, polarization, diffraction, interference, and spectroscopy. A variety of commercial light sensors are available from scientific vendors such as the CI-6504A from PASCO scientific and the LS-BTA from Vernier Software and…

  12. LED instrument approach instruction display

    NASA Technical Reports Server (NTRS)

    Meredith, B. D.; Kelly, W. L., IV; Crouch, R. K.

    1979-01-01

    A display employing light emitting diodes (LED's) was developed to demonstrate the feasibility of such displays for presenting landing and navigation information to reduce the workload of general aviation pilots during IFR flight. The display consists of a paper tape reader, digital memory, control electronics, digital latches, and LED alphanumeric displays. A presentable digital countdown clock-timer is included as part of the system to provide a convenient means of monitoring time intervals for precise flight navigation. The system is a limited capability prototype assembled to test pilot reaction to such a device under simulated IFR operation. Pilot opinion indicates that the display is helpful in reducing the IFR pilots workload when used with a runway approach plate. However, the development of a compact, low power second generation display was recommended which could present several instructions simultaneously and provide information update capability. A microprocessor-based display could fulfill these requirements.

  13. Colorimetric characterization of LED luminaires

    NASA Astrophysics Data System (ADS)

    Costa, C. L. M.; Vieira, R. R.; Pereira, R. C.; Silva, P. V. M.; Oliveira, I. A. A.; Sardinha, A. S.; Viana, D. D.; Barbosa, A. H.; Souza, L. P.; Alvarenga, A. D.

    2015-01-01

    The Optical Metrology Division of Inmetro - National Institute of Metrology, Quality and Technology has recently started the colorimetric characterization of lamps by implementing Correlated Color Temperature (CCT) and Color Rendering Index (CRI) measurements of incandescent lamps, followed by the CFL, and LED lamps and luminaires. Here we present the results for the verification of the color characterization of samples of SSL luminaires for public as well as indoor illumination that are sold in Brazil.

  14. Luminescent ceramics for LED conversion

    NASA Astrophysics Data System (ADS)

    Raukas, M.; Wei, G.; Bergenek, K.; Kelso, J.; Zink, N.; Zheng, Y.; Hannah, M.; Stough, M.; Wirth, R.; Linkov, A.; Jermann, F.; Eisert, D.

    2011-03-01

    Many LED-based applications would benefit from more efficient and/or high lumen output devices that enable usage in both white and single color illumination schemes. In the present article we briefly review the materials research history leading to optical ceramic converters and discuss their typical characteristics. Recently demonstrated high performance values in terms of efficacy and external quantum efficiency in orange (amber) spectral region are described.

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

    SciTech Connect

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

    2009-03-31

    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.

  16. High-efficiency trichromatic LED backlight for mobile LCDs

    NASA Astrophysics Data System (ADS)

    Kim, Jin-Ha; Park, Moo Youn; Kim, Jin-Jong; Kim, Heedong; Jun, Joo-Hee; Park, Jae-Hyuk; Cho, Sung-Min; Lee, Dong-Woo; Hwang, Soo Ryong; Jeong, Ho-Seop

    2006-02-01

    Trichromatic LED backlights render higher color gamut and panel transmittance to the liquid crystal displays (LCDs) than yellow phosphor-converted white LED backlights can possibly do at their best. In realization, however, several technical challenges arise, such as color mixing, minimizing the total number of chips, and maintaining the color balance. We designed and demonstrated a backlight unit for 2.2 inch TFT LCD using two RGB 3-chip LEDs to assess the feasibility and the technical hurdles to overcome. The average brightness of the backlight is 2509cd/m2 at the input power of 200mW. The power efficiency is lower than but comparable to commercially available white LED backlights. The color gamut of the LC panel is increased from 53% to 78% when its conventional white LED backlight is replaced by the trichromatic LED backlight. Panel transmittance is expected to be enhanced as well by about 8%. The ambient temperature change was found to be the most significant cause of the color shift of the trichromatic LED backlight. The forward bias voltage can be used in the feedback, since it changes linearly with temperature.

  17. Spectral design flexibility of LED brings better life

    NASA Astrophysics Data System (ADS)

    Ou, Haiyan; Corell, Dennis; Ou, Yiyu; Poulsen, Peter B.; Dam-Hansen, Carsten; Petersen, Paul-Michael

    2012-03-01

    Light-emitting diodes (LEDs) are penetrating into the huge market of general lighting because they are energy saving and environmentally friendly. The big advantage of LED light sources, compared to traditional incandescent lamps and fluorescent light tubes, is the flexible spectral design to make white light using different color mixing schemes. The spectral design flexibility of white LED light sources will promote them for novel applications to improve the life quality of human beings. As an initial exploration to make use of the spectral design flexibility, we present an example: 'no blue' white LED light source for sufferers of disease Porphyria. An LED light source prototype, made of high brightness commercial LEDs applying an optical filter, was tested by a patient suffering from Porphyria. Preliminary results have shown that the sufferer could withstand the light source for much longer time than the standard light source. At last future perspectives on spectral design flexibility of LED light sources improving human being's life will be discussed, with focus on the light and health. The good health is ensured by the spectrum optimized so that vital hormones (melatonin and serotonin) are produced during times when they support human daily rhythm.

  18. Current State of the Art in High Brightness LEDs

    NASA Astrophysics Data System (ADS)

    Craford, George

    2007-03-01

    LED's have been commercially available since the 1960's. For many years they were used primarily for indicator applications. The remarkable increase in materials technology and efficiency that has been achieved since the early 1990's for AlInGaP red and amber LEDs, and InGaN green and blue LEDs, has enabled the penetration of markets such as outdoor display, signaling, and automotive brake light and turn signal applications. White LEDs, which are either blue LEDs combined with a phosphor, or a combination of red, green, and blue LEDs, are being used in emerging applications such as cell phone flash, television backlights, projection, and automotive headlights. In addition, to efficiency improvements these applications have required the development of higher power packages and, in some of these applications which are etendue limited, higher luminance devices. High power devices are commercially available which are capable of 140 lumens output and have an efficacy of around 70 lm/W for white emission. New package and chip technologies have been demonstrated which have a luminance of 38 mega nits (Mcd/m^2), approximately 50% more luminance than that of an automotive headlamp halogen bulb (˜25 mega nits). The recent progress in materials technology, packaging, and chip technology makes it clear that LED's will become important for general illumination applications. The rate of LED penetration of this market will depend upon continued increases in performance and lower costs as well as better control of the white spectral emission. Efficiency, current density, and costs are closely linked because the cost in dollars/lumen is inversely proportional to how many lumens can be realized from each unit of device area for a given device type. Performance as high as 138 lm/W, and over 40% wall plug efficiency, has been reported for low power research devices and over 90 lm/W for high power research devices. It is clear that high power commercial products with performance in

  19. Commercial Fishing.

    ERIC Educational Resources Information Center

    Florida State Dept. of Education, Tallahassee. Div. of Vocational Education.

    This document is a curriculum framework for a program in commercial fishing to be taught in Florida secondary and postsecondary institutions. This outline covers the major concepts/content of the program, which is designed to prepare students for employment in occupations with titles such as net fishers, pot fishers, line fishers, shrimp boat…

  20. Commercial applications

    NASA Technical Reports Server (NTRS)

    Togai, Masaki

    1990-01-01

    Viewgraphs on commercial applications of fuzzy logic in Japan are presented. Topics covered include: suitable application area of fuzzy theory; characteristics of fuzzy control; fuzzy closed-loop controller; Mitsubishi heavy air conditioner; predictive fuzzy control; the Sendai subway system; automatic transmission; fuzzy logic-based command system for antilock braking system; fuzzy feed-forward controller; and fuzzy auto-tuning system.

  1. Modulation bandwidth enhancement of white-LED-based visible light communications using electrical equalizations

    NASA Astrophysics Data System (ADS)

    Kwon, D. H.; Yang, S. H.; Han, S. K.

    2015-01-01

    Utilizing the modulation capability of LEDs, there have been many studies about convergence technology to combine illumination and communication. The visible light communication (VLC) system has several advantages such as high security, immunity to RF interference and lower additional cost than comparing to LEDs just for illumination. However, modulation bandwidth of LEDs is not enough for various wireless communication systems. Since the commercial LEDs are designed only for lighting systems; we need an effort to enhance the modulation characteristics of LEDs. When the area of LED is increased, internal junction capacitance of LED is also increased depending on the area of LEDs and then the RC delay time of LED is increased. As a result, the modulation bandwidth of LEDs is limited by large RC delay time. In addition, frequency response of commercial white LED is degraded by the slow response time of the used yellow phosphor. Thus, modulation bandwidth of VLC system is limited to several MHz which is not enough to accommodate high data rate transmission. In this paper, we designed equalization circuit using RLC component for compensating the white LEDs frequency response. Also, we used blue filtering to improve frequency response of white LEDs, which is degraded by yellow phosphorescent component. Power loss by optical filtering and distance is compensated by convex lens. Consequently, we extend the modulation bandwidth of VLC system from 3 MHz to more than 180 MHz, and it allows NRZ-OOK data transmission up to 400 Mbps at 50 cm.

  2. Remaining Sites Verification Package for the 100-B-20, 1716-B Maintenance Garage Underground Tank, Waste Site Reclassification Form 2006-019

    SciTech Connect

    L. M. Dittmer

    2006-09-27

    The 100-B-20 waste site, located in the 100-BC-1 Operable Unit of the Hanford Site, consisted of an underground oil tank that once serviced the 1716-B Maintenance Garage. The selected action for the 100-B-20 waste site involved removal of the oil tanks and their contents and demonstrating through confirmatory sampling that all cleanup goals have been met. In accordance with this evaluation, a reclassification status of interim closed out has been determined. The results demonstrate that the site will support future unrestricted land uses that can be represented by a rural-residential scenario. These results also show that residual concentrations support unrestricted future use of shallow zone soil and that contaminant levels remaining in the soil are protective of groundwater and the Columbia River.

  3. Developing Successful International Faculty Led Program

    ERIC Educational Resources Information Center

    Fabregas Janeiro, Maria G.; Fabre, Ricardo Lopez; Rosete, Rodrigo Tello

    2012-01-01

    Faculty Led Programs are study abroad experiences led by university professors. Faculty Led Programs are considered as an opportunity for college students, especially in the United States to attend a short-term international experience (Mills, 2010). Faculty Led Program is an international experience which is different from the traditional…

  4. Progress and challenges in GaN-on-Si LEDs

    NASA Astrophysics Data System (ADS)

    Fenwick, William

    2016-03-01

    Silicon substrates offer a variety of advantages over conventional LED substrates, including both their low cost and their compatibility with the existing semiconductor manufacturing infrastructure. Researchers have sought to avail themselves of these benefits by developing GaN LEDs on silicon substrates. Integration of the two materials, however, presents several technical challenges that have proven difficult to address. The main challenges are the large lattice mismatch between GaN and silicon and the large difference in thermal expansion coefficients. Solutions have begun to emerge in recent years, with Toshiba being the first to commercialize GaN-on-Si technology on 200mm substrates in 2013, and several companies now shipping GaN-on-Si LEDs. Toshiba has developed a novel buffer layer structure and MOCVD growth technology that controls strain, wafer bow, and cracking while also suppressing formation of dislocations. This technology allows for the growth of GaN epitaxial layers with minimal cracking and dislocation densities in the low 108 cm-2. Control of strain and wafer bow is critical for the epitaxial process, and this requires very fine control over both absolute wafer temperature and temperature uniformity. Toshiba's technology controls temperature uniformity very well, and Toshiba has demonstrated wavelength uniformity with σ=2nm across a 200mm wafer. Thin film LEDs fabricated from these materials have efficiencies on par with the best efficiencies of LEDs grown on conventional substrates. Blue LED wall-plug efficiencies of ~83% are demonstrated.

  5. A thermosyphon heat pipe cooler for high power LEDs cooling

    NASA Astrophysics Data System (ADS)

    Li, Ji; Tian, Wenkai; Lv, Lucang

    2016-08-01

    Light emitting diode (LED) cooling is facing the challenge of high heat flux more seriously with the increase of input power and diode density. The proposed unique thermosyphon heat pipe heat sink is particularly suitable for cooling of high power density LED chips and other electronics, which has a heat dissipation potential of up to 280 W within an area of 20 mm × 22 mm (>60 W/cm2) under natural air convection. Meanwhile, a thorough visualization investigation was carried out to explore the two phase flow characteristics in the proposed thermosyphon heat pipe. Implementing this novel thermosyphon heat pipe heat sink in the cooling of a commercial 100 W LED integrated chip, a very low apparent thermal resistance of 0.34 K/W was obtained under natural air convection with the aid of the enhanced boiling heat transfer at the evaporation side and the enhanced natural air convection at the condensation side.

  6. Commercial Capaciflector

    NASA Technical Reports Server (NTRS)

    Vranish, John M.

    1991-01-01

    A capacitive proximity/tactile sensor with unique performance capabilities ('capaciflector' or capacitive reflector) is being developed by NASA/Goddard Space Flight Center (GSFC) for use on robots and payloads in space in the interests of safety, efficiency, and ease of operation. Specifically, this sensor will permit robots and their attached payloads to avoid collisions in space with humans and other objects and to dock these payloads in a cluttered environment. The sensor is simple, robust, and inexpensive to manufacture with obvious and recognized commercial possibilities. Accordingly, NASA/GSFC, in conjunction with industry, is embarking on an effort to 'spin' this technology off into the private sector. This effort includes prototypes aimed at commercial applications. The principles of operation of these prototypes are described along with hardware, software, modelling, and test results. The hardware description includes both the physical sensor in terms of a flexible printed circuit board and the electronic circuitry. The software description will include filtering and detection techniques. The modelling will involve finite element electric field analysis and will underline techniques used for design optimization.

  7. Color tunable LED spot lighting

    NASA Astrophysics Data System (ADS)

    Hoelen, C.; Ansems, J.; Deurenberg, P.; van Duijneveldt, W.; Peeters, M.; Steenbruggen, G.; Treurniet, T.; Valster, A.; ter Weeme, J. W.

    2006-08-01

    A new trend in illumination is to use dynamic light to set or dynamically vary the ambience of a room or office. For this we need color tunable spots that can reliably vary over at least a wide range of color temperatures, and preferably also more saturated colors. LEDs are in principle ideally suited for this application thanks to their nature of emitting light in a relatively narrow band. For color tunable spot lighting based on the concept of mixing RGB LED colors, the key results have been presented before. Limitations of these 3-intrinsic-color mixing systems with high color rendering properties are found in a limited operating temperature range due to wavelength shifts, a limited color temperature range, and a low maximum operating temperature due to a strong flux decrease with increasing temperature. To overcome these limitations, a 3-color R pcGB system with phosphor-converted red (R pc) and a 4-color RAGB system have been investigated. With both systems, a CRI of at least 80 can be maintained over the relevant color temperature range of approximately 2700 K to 6500 K. In this paper we compare these concepts on overall system aspects and report on the performance of prototype spot lamps. The main features of the RAGB and R pcGB spot lamp concepts can be summarized as: 1) The RAGB spot overcomes CRI and gamut shortcomings of RGB light sources and gives much freedom in wavelength selection, but suffers from temperature sensitivity and complex controls; 2) The R pcGB spot overcomes shortcomings concerning CRI and thermal dependence of RGB sources and enables relatively simple controls, but needs an improved overall red efficacy. With both color concepts, prototype spot lamps have been built. The amber to red emitting nitridosilicate-based phosphors can be wavelength-tuned for optimal performance, which is found at a peak emission around 610 nm for high color quality systems. This results in a simple and very robust system with good color consistency. For the

  8. Successful commercialization of nanophotonic technology

    NASA Astrophysics Data System (ADS)

    Jaiswal, Supriya L.; Clarke, Roger B. M.; Hyde, Sam C. W.

    2006-08-01

    The exploitation of nanotechnology from proof of principle to realizable commercial applications encounters considerable challenges in regards to high volume, large scale, low cost manufacturability and social ethics. This has led to concerns over converting powerful intellectual property into realizable, industry attractive technologies. At The Technology Partnership we specifically address the issue of successful integration of nanophotonics into industry in markets such as biomedical, ophthalmic, energy, telecommunications, and packaging. In this paper we draw on a few examples where we have either developed industrial scale nanophotonic technology or engineering platforms which may be used to fortify nano/microphotonic technologies and enhance their commercial viability.

  9. Commercial LANDSAT?

    NASA Astrophysics Data System (ADS)

    Private industry should assume responsibility either for the United States' land satellite (LANDSAT) system or for both the land and the weather satellite systems, recommends the Land Remote Sensing Satellite Advisory Committee. The committee (Eos, June 29, 1982, p. 553), composed of representatives from academia, industry, and government, has a working group that is evaluating the potential for commercialization of remote sensing satellites.The recommendations call for industry ownership or operation of either or both of the remote sensing systems, but only up to and including the holding of raw, unprocessed data. The National Aeronautics and Space Administration (NASA) currently operates LANDSAT but will be relinquishing its responsibility to the National Oceanic and Atmospheric Administration (NOAA) on January 31. NOAA already operates the U.S. civilian weather satellite service, which includes the NOAA-5, NOAA-6, and the Geostationary Operational Environmental (GOES) satellites (Eos, June 2, 1981, p. 522).

  10. Color temperature tunable white light LED system

    NASA Astrophysics Data System (ADS)

    Speier, Ingo; Salsbury, Marc

    2006-08-01

    Efficient white light LED systems with continuously tunable color temperature (CT) over a range of 3000 K to 6500 K are reviewed. Typically, white light sources have a fixed CT and color rendering index (CRI). White light with user-specified color temperatures is currently generated by solid-state systems with red green blue ("R/G/B"), red green blue amber ("R/G/B/A"), and warm white cool white ("WW/CW") LED combinations, but their performance is suboptimal for architectural lighting applications. We propose and discuss an LED module with a combination of warm white, green and blue ("WW/G/B") LEDs. In this scenario, the white LEDs have fixed intensity, while the blue and green LED intensities are adjusted to shift the LED module chromaticity along the blackbody locus. We also propose and discuss an LED module with a combination of red, green, blue, and cool white ("R/G/B/CW") LEDs. The white LEDs still have a fixed intensity, while the intensities of the red, green, and blue LEDs are again adjusted to shift the LED module chromaticity along the blackbody locus. The white LEDs ensure that an improved CRI is maintained in comparison to a simple "R/G/B" solution.

  11. Color Maintenance of LEDs in Laboratory and Field Applications

    SciTech Connect

    Royer, Michael P.; Tuttle, Ralph; Rosenfeld, Scott M.; Miller, Naomi J.

    2013-09-30

    Synopsis: To date, consideration for parametric failure of LED products has largely been focused on lumen maintenance. However, color shift is a cause of early failure for some products, and is especially important to consider in certain applications, like museums, where visual appearance is critical. Example data collected by the GATEWAY program for LED lamps installed in museums shows that many have changed color beyond a reasonable tolerance well before their rated lifetime was reached, necessitating replacement. Similar data collected by the CALiPER program between 2008 and 2010 reveals that many early products shifted beyond acceptable tolerances in as little as a few thousand hours. In contrast, data from the L Prize program illustrates that commercially available LED products can have exemplary color stability that is unmatched by traditional light sources. Beyond presenting data from the aforementioned DOE programs, this report discusses the metrics used for communicating color shift—namely MacAdam ellipses and Δu'v'—as well as providing guidance for end users on how to monitor color shift and what to look for in manufacturer warranties. Also included are descriptions of the physical changes that have been documented as leading to color shift in some example types of LED packages. As with complete products, the data presented herein for LED packages shows that a wide variety of products are available; in order for specifiers and consumers to make educated choices, more detailed and standardized information should be made available.

  12. LEDs for Street Lighting—Here Today

    SciTech Connect

    2013-11-29

    Fact sheet that provides a brief overview of the viability of LED street lighting in municipalities and highlights case studies of two cities—Los Angeles and Seattle—that have invested in LED street lighting.

  13. Commercial applications

    NASA Astrophysics Data System (ADS)

    The near term (one to five year) needs of domestic and foreign commercial suppliers of radiochemicals and radiopharmaceuticals for electromagnetically separated stable isotopes are assessed. Only isotopes purchased to make products for sale and profit are considered. Radiopharmaceuticals produced from enriched stable isotopes supplied by the Calutron facility at ORNL are used in about 600,000 medical procedures each year in the United States. A temporary or permanent disruption of the supply of stable isotopes to the domestic radiopharmaceutical industry could curtail, if not eliminate, the use of such diagnostic procedures as the thallium heart scan, the gallium cancer scan, the gallium abscess scan, and the low radiation dose thyroid scan. An alternative source of enriched stable isotopes exist in the USSR. Alternative starting materials could, in theory, eventually be developed for both the thallium and gallium scans. The development of a new technology for these purposes, however, would take at least five years and would be expensive. Hence, any disruption of the supply of enriched isotopes from ORNL and the resulting unavailability of critical nuclear medicine procedures would have a dramatic negative effect on the level of health care in the United States.

  14. Attendees' Perceptions of Commercial Influence in Noncommercially Funded CME Programs

    ERIC Educational Resources Information Center

    Goldfarb, Elizabeth; Baer, Lee; Fromson, John A.; Gorrindo, Tristan; Iodice, Kristin E.; Birnbaum, Robert J.

    2012-01-01

    Introduction: The controversy surrounding commercial support for continuing medical education (CME) programs has led to policy changes, but data show no significant difference in perceived bias between commercial and noncommercial CME. Indeed, what attendees perceive as commercial influence is not fully understood. We sought to clarify what…

  15. Dual LED/incandescent security fixture

    DOEpatents

    Gauna, Kevin Wayne

    2005-06-21

    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.

  16. Miniature LED endoilluminators for vitreoretinal surgery

    NASA Astrophysics Data System (ADS)

    Hessling, M.; Koelbl, P. S.; Lingenfelder, C.; Koch, F.

    2015-07-01

    Two innovative approaches for intraocular illumination during vitreoretinal surgery by application of white LEDs are being developed. Both techniques are less harmful to the patient, more convenient for the surgeon and smaller and cheaper compared to conventional illumination by Xenon light sources and optical fibers. These two novel approaches are: I) The miniature LED chandelier endoilluminator consisting of a single white LED with a "light probe" on top of the LED housing that fits in a small incision in the wall of the eye. II) The alternative transscleral LED endoilluminator is integrated into an eye speculum that presses the flat LED top against the eye. The intraocular space is only illuminated by light transmitted through the sclera. In contrast to conventional illumination techniques for vitreoretinal surgery no incision is necessary. Both approaches are evaluated with regard to potential photochemical and thermal risks for the patient's retina and they are tested on porcine eyes.

  17. Nurse-led treatment for occipital neuralgia.

    PubMed

    Pike, Denise; Amphlett, Alexander; Weatherby, Stuart

    Occipital neuralgia is a headache resulting from dysfunction of the occipital nerves. Medically resistant occipital neuralgia is treated by greater occipital nerve injection, which is traditionally performed by neurologists. A nurse-led clinic was developed to try to improve the service. Patient feedback showed that the clinic was positively perceived by patients, with most stating the nurse-led model was more efficient than the previous one, which had been led by consultants. PMID:26455130

  18. Liquid explosive detection using near infrared LED

    NASA Astrophysics Data System (ADS)

    Itozaki, Hideo; Ito, Shiori; Sato-Akaba, Hideo; Miyato, Yuji

    2015-10-01

    A bottle scanner to detect liquid explosive has been developed using technologies of near infrared. Its detection rate of liquid explosive is quite high and its false alarm rate of safe liquids quite low. It uses a light source with wide spectrum such as a halogen lamp. Recently a variety of LEDs have been developed and some of them have near infrared spectrum. Here a near infrared LED is tested as a light source of the liquid explosive detector. Three infrared LEDs that have a main peak of spectrum at 901nm, 936nm, and 1028 nm have been used as a light source to scan liquids. Spectrum widths of these LEDs are quite narrow typically less than 100 nm. Ten typical liquids have been evaluated by these LEDs and the correlation coefficients of a spectrum by an LED and a tungsten lamp were more than 0.98. This experiment shows that the infrared LED can be used as a light source for the liquid scanner. An LED has some merits, such as long life of more than some ten thousand hours and small consumption electric power of less than 0.2 W. When the LED is used as a light source for the liquid scanner, it is also more compact and handy.

  19. Solid State Lighting LED Manufacturing Roundtable Summary

    SciTech Connect

    none,

    2010-03-31

    Summary of a meeting of LED experts to develop proposed priority tasks for the Manufacturing R&D initiative, including task descriptions, discussion points, recommendations, and presentation highlights.

  20. Blue LEDs feasibility for tissue fluorescence analysis

    NASA Astrophysics Data System (ADS)

    Dets, Sergiy M.; Denisov, Nikolay A.

    2000-04-01

    We considered the limited number of light-induced fluorescence applications for marketed ultra-bright blue LEDs where they can compete with versatile laser sources. Satisfactory optical output and miniature size as well as low power consumption of blue LEDs emitting at 470 nm allow to consider them as a promising alternatives to metal vapor or gas lasers used in many expires LIF applications. Available to authors LEDs form Hewlett-Packard, Micro Electronics Corp., Nichia Chemical Industries Ltd. and Toyoda Gosei Co. were tested to comply with demands to a tissue excitation source for portable spectroscopes. The optical performance of LEDs has shown that selected group of InGaN LEDs could be successfully used for that. The miniature illuminator that includes LED, focusing condenser, filter set and distal fiberoptic light concentrator was designed and tested in conjunction with portable CCD- equipped spectroscope. Operating in dark condition the proposed LED illuminator provides the level of fluorescence signal sufficient to detect spectral abnormalities in human Caucasian skin and excised gastrointestinal samples. All tissue autofluorescence data taken under LED illumination were compared with readings under He-Cd laser excitation and showed a good match. A new diagnostic designs based on LEDs were considered for clinical use.

  1. Case Study on Combination of Fluorescent Materials for White LED to Obtain High Color Rendering Indexes

    NASA Astrophysics Data System (ADS)

    Nayama, Shunsuke; Itoh, Kunio

    This letter reports on white-LED with high color rendering property. We realized the white-LED whose average Color Rendering Index (CRI) is as high as 94.2 by applying the commercial Red, Yellow, Green and Blue phosphors to near ultraviolet-LED. So far as we know, this value is the highest ever attained in white-LED around the color temperature of 5500[K]. In order to realize the good Ra (average CRI), we made a CRI simulator and simulated the spectrum distribution of white-LED with good Ra. The spectrum distribution obtained by this simulation was proved to be very useful as a landmark for realizing a prototype white-LED with good Ra.

  2. 130 LPW 1000 Lm Warm White LED for Illumination

    SciTech Connect

    Soer, Wouter

    2012-06-14

    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

  3. LED illuminant on the ambient light

    NASA Astrophysics Data System (ADS)

    Liu, Anqing; Sandipan, Mishra; Shur, Michael

    2014-09-01

    We develop an approach for combining illuminance and spectral power distribution of the LED and ambient light and apply our technique for developing an LED camera flashlight balancing the illuminance contrast between object and background. Our method uses the closed loop, multiobjective optimization comprising: (1) characterizing the lighting task by illuminance, correlated color temperature (CCT), and statistical color quality indices that include a set of Statistical Color Quality Metrics and the Color Rendition Index (CRI) implemented with indexes of S (saturation) or D (dulling); (2) measuring the illuminance and the spectrum of the ambient light on the target lighting surface, which might depend on all the sources proving illumination and on the reflected light; (3) determining the desired illuminance of the LED source on the target lighting surface; (4) calculating the desired luminous flux of the LED source according to the desired illuminance; (5) constituting the SPD of the LED source; (6) calculating the relative spectra counts of the LED source and the ambient light on the target lighting surface (7) calculating the CCT and statistical color quality indexes of the combined light; (8) repeating the above steps until the resulting SPD is close enough to the expectation. Using the above method, an LED camera flashlight has been designed, which works together with usual fluorescent ambient light and generates working lighting environment with high fidelity and high CCT (6000K). The spectrum and luminous flux of the LED lamp is automatically tunable with a change of the ambient light.

  4. Today LED Holiday Lights, Tomorrow the World?

    SciTech Connect

    Gordon, Kelly L.

    2004-12-20

    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.

  5. Advances in LEDs for automotive applications

    NASA Astrophysics Data System (ADS)

    Bhardwaj, Jy; Peddada, Rao; Spinger, Benno

    2016-03-01

    High power LEDs were introduced in automotive headlights in 2006-2007, for example as full LED headlights in the Audi R8 or low beam in Lexus. Since then, LED headlighting has become established in premium and volume automotive segments and beginning to enable new compact form factors such as distributed low beam and new functions such as adaptive driving beam. New generations of highly versatile high power LEDs are emerging to meet these application needs. In this paper, we will detail ongoing advances in LED technology that enable revolutionary styling, performance and adaptive control in automotive headlights. As the standards which govern the necessary lumens on the road are well established, increasing luminance enables not only more design freedom but also headlight cost reduction with space and weight saving through more compact optics. Adaptive headlighting is based on LED pixelation and requires high contrast, high luminance, smaller LEDs with high-packing density for pixelated Matrix Lighting sources. Matrix applications require an extremely tight tolerance on not only the X, Y placement accuracy, but also on the Z height of the LEDs given the precision optics used to image the LEDs onto the road. A new generation of chip scale packaged (CSP) LEDs based on Wafer Level Packaging (WLP) have been developed to meet these needs, offering a form factor less than 20% increase over the LED emitter surface footprint. These miniature LEDs are surface mount devices compatible with automated tools for L2 board direct attach (without the need for an interposer or L1 substrate), meeting the high position accuracy as well as the optical and thermal performance. To illustrate the versatility of the CSP LEDs, we will show the results of, firstly, a reflector-based distributed low beam using multiple individual cavities each with only 20mm height and secondly 3x4 to 3x28 Matrix arrays for adaptive full beam. Also a few key trends in rear lighting and impact on LED light

  6. 100 LPW 800 Lm Warm White LED

    SciTech Connect

    Sun, Decai

    2010-10-31

    An illumination grade warm white (WW) LED, having correlated color temperature (CCT) between 2800 K and 3500K and capable of producing 800 lm output at 100 lm/W, has been developed in this program. The high power WW LED is an ideal source for use as replacement for incandescent, and Halogen reflector and general purpose lamps of similar lumen value. Over the two year period, we have made following accomplishments: developed a high power warm white LED product and made over 50% improvements in light output and efficacy. The new high power WW LED product is a die on ceramic surface mountable LED package. It has four 1x1 mm{sup 2} InGaN pump dice flip chip attached to a ceramic submount in 2x2 array, covered by warm white phosphor ceramic platelets called Lumiramica and an overmolded silicone lens encapsulating the LED array. The performance goal was achieved through breakthroughs in following key areas: (1) High efficiency pump LED development through pump LED active region design and epi growth quality improvement (funded by internal programs). (2) Increase in injection efficiency (IE) represented by reduction in forward voltage (V{sub f}) through the improvement of the silver-based p-contact and a reduction in spreading resistance. The injection efficiency was increased from 80% at the start of the program to 96% at the end of the program at 700 mA/mm{sup 2}. (3) Improvement in thermal design as represented by reduction in thermal resistance from junction to case, through improvement of the die to submount connection in the thin film flip chip (TFFC) LED and choosing the submount material of high thermal conductivity. A thermal resistance of 1.72 K/W was demonstrated for the high power LED package. (4) Improvement in extraction efficiency from the LED package through improvement of InGaN die level and package level optical extraction efficiency improvement. (5) Improvement in phosphor system efficiency by improving the lumen equivalent (LE) and phosphor package

  7. Accurate colorimetric feedback for RGB LED clusters

    NASA Astrophysics Data System (ADS)

    Man, Kwong; Ashdown, Ian

    2006-08-01

    We present an empirical model of LED emission spectra that is applicable to both InGaN and AlInGaP high-flux LEDs, and which accurately predicts their relative spectral power distributions over a wide range of LED junction temperatures. We further demonstrate with laboratory measurements that changes in LED spectral power distribution with temperature can be accurately predicted with first- or second-order equations. This provides the basis for a real-time colorimetric feedback system for RGB LED clusters that can maintain the chromaticity of white light at constant intensity to within +/-0.003 Δuv over a range of 45 degrees Celsius, and to within 0.01 Δuv when dimmed over an intensity range of 10:1.

  8. High Performance Green LEDs by Homoepitaxial

    SciTech Connect

    Wetzel, Christian; Schubert, E Fred

    2009-11-22

    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.

  9. White LEDs with limit luminous efficacy

    NASA Astrophysics Data System (ADS)

    Lisitsyn, V. M.; Lukash, V. S.; Stepanov, S. A.; Yangyang, Ju

    2016-01-01

    In most promising widespread gallium nitride based LEDs emission is generated in the blue spectral region with a maximum at about 450 nm which is converted to visible light with the desired spectrum by means of phosphor. The thermal energy in the conversion is determined by the difference in the energies of excitation and emission quanta and the phosphor quantum yield. Heat losses manifest themselves as decrease in the luminous efficacy. LED heating significantly reduces its efficiency and life. In addition, while heating, the emission generation output and the efficiency of the emission conversion decrease. Therefore, the reduction of the energy losses caused by heating is crucial for LED development. In this paper, heat losses in phosphor-converted LEDs (hereinafter chips) during spectrum conversion are estimated. The limit values of the luminous efficacy for white LEDs are evaluated.

  10. Using LEDs to reduce energy consumption

    NASA Astrophysics Data System (ADS)

    Eweni, Chukwuebuka E.

    The most popularly used light bulb in homes is the incandescent. It is also the least energy efficient. The filament in the bulb is so thin that it causes resistance in the electricity, which in turn causes the electricity's energy to form heat. This causes the incandescent to waste a lot of energy forming heat rather than forming the light. It uses 15 lumens per watt of input power. A recorded MATLAB demonstration showcased LED versatility and how it can be used by an Arduino UNO board. The objective of this thesis is to showcase how LEDs can reduce energy consumption through the use of an Arduino UNO board and MATLAB and to discuss the applications of LED. LED will be the future of lighting homes and will eventually completely incandescent bulbs when companies begin to make the necessary improvements to the LED.

  11. Addressing the variables in LED product design to ensure product reliability

    NASA Astrophysics Data System (ADS)

    Keebler, Philip F.; Sharp, Frank D.

    2011-10-01

    Continuing developments in LED lighting are leading to more lighting products for illumination in LED fixtures for the residential, commercial, and industrial facilities. Most of the research in the past ten years has been aimed at developing LEDs with higher brightness, higher efficacies, good color performance and longer life. Many efforts have been accomplished to develop LED driver circuits to drive LED arrays, even drivers that are dimmable. Manufacturers are increasing their level of concern with the performance and life of the whole LED product with a renewed emphasis on reliability. Reliability for LED products not only involves thermal management, fixture design, and driver loading but also how products respond to electrical disturbances that occur in the building electrical environments where the products must function. EPRI research has demonstrated that the immunity of LED lighting systems to common everyday electrical disturbances is critical to establishing the reliability needed to ensure expected performance and for their survival during product life. Test results showing the application of voltage surges, transients, and sags among other disturbances will be presented. This paper will discuss the application of the results of EPRI research in this area, the test protocol associated with EPRI system compatibility concept, examples of how applying the concept has identified reliability problems in LED products, and how the reliability of these LED systems can be easily improved.

  12. High-power LED package requirements

    NASA Astrophysics Data System (ADS)

    Wall, Frank; Martin, Paul S.; Harbers, Gerard

    2004-01-01

    Power LEDs have evolved from simple indicators into illumination devices. For general lighting applications, where the objective is to light up an area, white LED arrays have been utilized to serve that function. Cost constraints will soon drive the industry to provide a discrete lighting solution. Early on, that will mean increasing the power densities while quantum efficiencies are addressed. For applications such as automotive headlamps & projection, where light needs to be tightly collimated, or controlled, arrays of die or LEDs will not be able to satisfy the requirements & limitations defined by etendue. Ultimately, whether a luminaire requires a small source with high luminance, or light spread over a general area, economics will force the evolution of the illumination LED into a compact discrete high power package. How the customer interfaces with this new package should be an important element considered early on in the design cycle. If an LED footprint of adequate size is not provided, it may prove impossible for the customer, or end user, to get rid of the heat in a manner sufficient to prevent premature LED light output degradation. Therefore it is critical, for maintaining expected LED lifetime & light output, that thermal performance parameters be defined, by design, at the system level, which includes heat sinking methods & interface materials or methdology.

  13. Novel silicone materials for LED packaging

    NASA Astrophysics Data System (ADS)

    Norris, Ann W.; Bahadur, Maneesh; Yoshitake, Makoto

    2005-09-01

    Silicone based materials have attracted considerable attention from Light Emitting Diode (LED) manufacturers for use as encapsulants and lenses for many next generation LED device designs. Silicones can function in several roles that include protective lenses, stress relieving encapsulants, mechanical protection and light path materials. The key attributes of silicones that make them attractive materials for high brightness (HB) LEDs include their high transparency in the UV-visible region, controlled refractive index (RI), stable thermo-mechanical properties, and tuneable hardness from soft gels to hard resins. The high current and high operating temperatures of HB-LEDs present a significant materials challenge for traditional organic materials such as epoxies, acrylics and cyclo olefin copolymers (COC) that lack the thermal and molecular stability needed to provide optical clarity and mechanical performance required for next generation devices. In addition, the retention of optical clarity over the lifetime of the device, which involves long term exposure to high flux in the UV-visible wavelength region, is a critical requirement. Silicones have been demonstrated to provide the required stability. This paper will describe recent silicone materials development efforts directed towards providing LED manufacturers with silicone materials solutions for LED device fabrication. Injection molding of novel silicone resin based materials will be discussed as a surmountable challenge for high throughput LED device manufacturing.

  14. LED-driven backlights for automotive displays

    NASA Astrophysics Data System (ADS)

    Strauch, Frank

    2007-09-01

    As a light source the LED has some advantage over the traditionally used fluorescence tube such as longer life or lower space consumption. Consequently customers are asking for the LED lighting design in their products. We introduced in a company owned backlight the white LED technology. This step opens the possibility to have access to the components in the display market. Instead of having a finalized display product which needs to be integrated in the head unit of a car we assemble the backlight, the glass, own electronics and the housing. A major advantage of this concept is the better control of the heat flow generated by the LEDs to the outer side because only a common housing is used for all the components. Also the requirement for slim products can be fulfilled. As always a new technology doesn't come with advantages only. An LED represents a point source compared to the well-known tube thus requiring a mixing zone for the multiple point sources when they enter a light guide. This zone can't be used in displays because of the lack of homogeneity. It's a design goal to minimize this zone which can be helped by the right choice of the LED in terms of slimness. A step ahead is the implementation of RGB LEDs because of their higher color rendering abilities. This allows for the control of the chromaticity point under temperature change but as a drawback needs a larger mixing zone.

  15. Thermal management of LEDs: package to system

    NASA Astrophysics Data System (ADS)

    Arik, Mehmet; Becker, Charles A.; Weaver, Stanton E.; Petroski, James

    2004-01-01

    Light emitting diodes, LEDs, historically have been used for indicators and produced low amounts of heat. The introduction of high brightness LEDs with white light and monochromatic colors have led to a movement towards general illumination. The increased electrical currents used to drive the LEDs have focused more attention on the thermal paths in the developments of LED power packaging. The luminous efficiency of LEDs is soon expected to reach over 80 lumens/W, this is approximately 6 times the efficiency of a conventional incandescent tungsten bulb. Thermal management for the solid-state lighting applications is a key design parameter for both package and system level. Package and system level thermal management is discussed in separate sections. Effect of chip packages on junction to board thermal resistance was compared for both SiC and Sapphire chips. The higher thermal conductivity of the SiC chip provided about 2 times better thermal performance than the latter, while the under-filled Sapphire chip package can only catch the SiC chip performance. Later, system level thermal management was studied based on established numerical models for a conceptual solid-state lighting system. A conceptual LED illumination system was chosen and CFD models were created to determine the availability and limitations of passive air-cooling.

  16. Thermoresponsive scattering coating for smart white LEDs

    NASA Astrophysics Data System (ADS)

    Cornelissen, Hugo J.; Yu, Joan; Cennini, Giovanni; Bauer, Jurica; Verbunt, Paul P. C.; Bastiaansen, Cees W. M.; Broer, Dirk J.

    2015-09-01

    A novel responsive lighting system is presented capable of lowering the color temperature of emitted light on dimming. It is based on a single white light emitting LED and a thermo-responsive scattering coating. The coated LED automatically emits light of lower correlated color temperature (CCT) when the power is reduced, while maintaining a chromaticity close to the black body curve. Existing systems all use multiple color LEDs, additional control circuitry and mixing optics. An optical ray tracing model can explain the experimental results.

  17. The Latest Trends in LED Lighting

    NASA Astrophysics Data System (ADS)

    Bessho, Makoto; Shimizu, Keiichi

    LED is regarded as the latest and the fourth generation of light sources following incandescent lamps as the first generation, fluorescent lamps as the second generation, and HID lamps as the third generation. Excellent characteristics, such as high efficiency, long life, compactness, light weight, mercury free, very weak IR and UV emission, etc. are their advantage in comparison with the conventional light sources. With the progress of LED lighting technologies, their application is spreading in sign and display device, spot lighting, base lighting, security lighting, and further, new market, which is impossible to realize by the conventional light sources, is expected. This article reports the latest trend in LED lighting.

  18. Integrating sphere design for characterization of LED efficacy

    NASA Astrophysics Data System (ADS)

    Mujahid, Muhammad Abdul Aziz Al; Panatarani, C.; Maulana, Dwindra W.; Wibawa, Bambang Mukti; Joni, I. Made

    2016-02-01

    The integrating sphere (IS) is one of the most important device in characterization of illuminance of a light source, such as CFL, LED etc. to obtain their efficacy. IS is a hollowed sphere with its interior covered with a diffuse white reflective coating where its accuracy of the measurement is highly affected by reflectance of its interior coating. This paper report the preparation of inner surface coating of the IS with inner diameter of 25 cm attempt to create a durable and highly reflective interior coating by combining BaSO4 with a binding material (either Polyethylene Glycol (PEG) or white paint). The various inner surface coating mixture vary in weight % ratio of BaSO4:PEG or BaSO4:white paint were investigated. The results show that the inner surface coating mixture of BaSO4:PEG (99.8:0.2) has highest reflectance compared to others mixture. The IS with best mixture was calibrated with white LED and resulted an average sphere multiplier (M) was 8.7, and average reflectance (ρ) was 0.90. The result of the relative error of luminescence measurement using calibrated M and ρ is 6.7 %. It is concluded that the developed IS produced lower allowed error compared to the commercially available IS. However at lower wavelength shows lower intensity compare to the available datasheet of the LED under investigation.

  19. Peer-Led and Adult-Led Programs--Student Perceptions.

    ERIC Educational Resources Information Center

    Erhard, Rachel

    1999-01-01

    Examines whether peer-led drug prevention programs are preferable to adult-led programs for students (N=2,447) in eighth through eleventh grades. Results show that all input measures and outcome measures were perceived as more positive in the peer-led model. Since the differences found were small this study does not prove with certainty that the…

  20. LED Outdoor Area Lighting Fact Sheet

    SciTech Connect

    2008-06-01

    This fact sheet reviews the major design and specification concerns for outdoor area lighting, and discusses the potential for LED luminaires to save energy while providing high quality lighting for outdoor areas.

  1. Optimized design of LED plant lamp

    NASA Astrophysics Data System (ADS)

    Chen, Jian-sheng; Cai, Ruhai; Zhao, Yunyun; Zhao, Fuli; Yang, Bowen

    2014-12-01

    In order to fabricate the optimized LED plant lamp we demonstrated an optical spectral exploration. According to the mechanism of higher plant photosynthesis process and the spectral analysis we demonstrate an optical design of the LED plant lamp. Furthermore we built two kins of prototypes of the LED plant lamps which are suitable for the photosynthesis of higher green vegetables. Based on the simulation of the lamp box of the different alignment of the plants we carried out the growing experiment of green vegetable and obtain the optimized light illumination as well as the spectral profile. The results show that only blue and red light are efficient for the green leave vegetables. Our work is undoubtedly helpful for the LED plant lamping design and manufacture.

  2. Heterostructure optimization for increasing LED efficiency

    NASA Astrophysics Data System (ADS)

    Rabinovich, Oleg; Legotin, Sergey; Didenko, Sergey; Yakimov, Evgeniy; Osipov, Yuriy; Fedorchenko, Irina

    2016-05-01

    Computer simulations were performed to increase the quantum efficiency of LED by optimizing the nanoheterostructure (NH). Furthermore, the InGaN and AlGaP NHs for LEDs were optimized. On the basis of the optimum NH, ways to further increase the efficiency and the influence of impurities and indium atoms doped into barriers between quantum wells were investigated. The optimum impurity and indium atom concentrations to achieve higher flux were determined.

  3. MOVPE of III-N LED structures with short technological process

    NASA Astrophysics Data System (ADS)

    Lundin, W. V.; Davydov, D. V.; Zavarin, E. E.; Popov, M. G.; Sakharov, A. V.; Yakovlev, E. V.; Bazarevskii, D. S.; Talalaev, R. A.; Tsatsulnikov, A. F.; Mizerov, M. N.; Ustinov, V. M.

    2015-03-01

    The paper presents results on optimizing the MOVPE technology of light-emitting diode (LED) structures in a Dragon-125 system to accelerate the technological cycle. Due to the high growth rate of GaN layers and optimization of the initial GaN growth phase, the total duration of the epitaxial process is reduced from 4 h 45 min to 2 h 44 min. The LED diode structures grown by this technique compare well in quality with LEDs grown by the standard method in the commercially available AIX2000HT system.

  4. Investigation of the spectral properties of LED-based MR16s for general illumination

    NASA Astrophysics Data System (ADS)

    Brown, David F.; Nicol, David B.; Payne, Adam; Ferguson, Ian T.

    2004-10-01

    The spectral properties of commercially available LED-based and halogen MR16s were investigated. The measurements taken include TLF (Total Luminous Flux), CCT (Correlated Color Temperature), CRI (Color Rendering Index), angular variation of CCT, and luminous efficacy. The halogen MR16s were used as a baseline for comparison with LED-based MR16s. It is shown at this time that LED-based MR16s are not suitable as a direct replacement for existing alternatives due to high initial cost, low power efficiency, poor CRIs, and undesirable CCTs.

  5. LED luminaire longevity strategy models comparison

    NASA Astrophysics Data System (ADS)

    Lemieux, Hugo; Thibault, Simon; Martel, Alain A.

    2010-08-01

    As energy efficiency becomes more and more important, light-emitting diodes (LEDs) are a promising alternative to traditional lighting. Indeed, the energy efficiency of LEDs is still improving as their luminosity is modulated by current. Moreover, for applications such as exterior lamp posts, their small size, directionality, colors and high frequency response allow to combine them and provide design possibilities which are impossible with any other light source. However, as any lamp, LEDs have a lumen depreciation which is a function of both current and temperature. Thus, to take advantage of the full characteristics of LEDs, LED luminaire longevity strategies must be carefully studied and planned, especially since the IES and CIE guidelines state clearly that the luminaire must maintain the rated recommended light level until the end of the system's operating life. The recommended approach for LED luminaire specification is therefore to use the end-of-life light level when evaluating the luminaire. Different power supply strategies have been simulated to determine which one maximizes energy saving and lifetime. With these results, it appears that active control can save at least 25% in energy, but the best strategy cannot be determined because of uncertainties in luminosity degradation models.

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

    SciTech Connect

    Not Available

    2014-03-01

    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.

  7. Comparison of improved operating parameters of five different wavelength LEDs for significantly brighter illumination

    NASA Astrophysics Data System (ADS)

    Mueller, Eduard K.; Lee, Susanne M.; Van de Workeen, Brian C.; Mueller, Otward M.

    2001-05-01

    Although light-emitting diodes exhibit much higher efficiencies and greatly reduced power consumption compared to incandescent light sources, the use of LEDs in lighting applications is limited by their smaller size and subsequently lower light output. However, it has been found that these parameters can be increased significantly by cooling the diodes to cryogenic temperatures. This may make their use feasible for several applications requiring more efficient and brighter illumination for much less cost. In this paper, we compare the temperature-dependent behavior of five commercially available LEDs of different wavelengths down to liquid nitrogen temperatures. It was found that three AlInGaP diodes (red, yellow, and green) demonstrated significant operating improvements. The performance of InGaN-based blue LEDs declined at low temperatures, and because most white LEDs are simply blue LEDs coated with YAG, these exhibited similar behavior. However, the three AlInGaP LEDs demonstrated at least an order of magnitude improvement in illuminance, absolute intensity, and maximum operating current. The green LEDs showed the largest improvement factors, while the yellow LEDs produced the brightest illumination at low temperatures. The emissions of all five LEDs shifted to shorter wavelengths at low temperatures. This is significant in terms of lighting applications since the low-temperature AlInGaP diodes emitted more visible spectra.

  8. Thermal Analysis of LED Phosphor Layer

    NASA Astrophysics Data System (ADS)

    Perera, Ukwatte Lokuliyanage Indika Upendra

    Solid-state lighting technology has progressed to a level where light-emitting diode (LED) products are either on par or better than their traditional lighting technology counterparts with respect to efficacy and lifetime. At present, the most common method to create "white" light from LEDs for illumination applications is by using the LED primary radiation and wavelength-converting materials. In this method, the re-emission from the wavelength-converting materials excited by the LED primary radiation is combined with the LED primary radiation to create the "white" light. During this conversion process, heat is generated as a result of conversion inefficiencies and other loss mechanisms in the LED and the wavelength-converting materials. This generated heat, if not properly dissipated, increases the operating temperature, thereby increasing the light output degradation of the system over both the short and long term. The heat generation of the LED and thermal management of the LED have been studied extensively. Methods to effectively dissipate heat from the LEDs and maintain lower LED operating temperature are well understood. However, investigation of factors driving heat generation, the resulting temperature distribution in the phosphor layer, and the influence of the phosphor layer temperature on LED performance and reliability have not received the same focus. The goal of this dissertation was to understand the main factors driving heat and light generation and the transport of light and heat in the wavelength-converting layer of an LED system. Another goal was to understand the interaction between heat and light in the system and to develop and analyze a solution to reduce the wavelength-converting layer operating temperature, thereby improving light output and reliability. Even though past studies have explored generation and transfer separately for light and heat, to the best of the author's knowledge, this is the first study that has analyzed both factors

  9. Affordable underwater wireless optical communication using LEDs

    NASA Astrophysics Data System (ADS)

    Pilipenko, Vladimir; Arnon, Shlomi

    2013-09-01

    In recent years the need for high data rate underwater wireless communication (WC) has increased. Nowadays, the conventional technology for underwater communication is acoustic. However, the maximum data rate that acoustic technology can provide is a few kilobits per second. On the other hand, emerging applications such as underwater imaging, networks of sensors and swarms of underwater vehicles require much faster data rates. As a result, underwater optical WC, which can provide much higher data rates, has been proposed as an alternative means of communication. In addition to high data rates, affordable communication systems become an important feature in the development requirements. The outcome of these requirements is a new system design based on off-the-shelf components such as blue and green light emitting diodes (LEDs). This is due to the fact that LEDs offer solutions characterized by low cost, high efficiency, reliability and compactness. However, there are some challenges to be met when incorporating LEDs as part of the optical transmitter, such as low modulation rates and non linearity. In this paper, we review the main challenges facing the incorporation of LEDs as an integral part of underwater WC systems and propose some techniques to mitigate the LED limitations in order to achieve high data rate communication

  10. Commercial Buildings Characteristics, 1992

    SciTech Connect

    Not Available

    1994-04-29

    Commercial Buildings Characteristics 1992 presents statistics about the number, type, and size of commercial buildings in the United States as well as their energy-related characteristics. These data are collected in the Commercial Buildings Energy Consumption Survey (CBECS), a national survey of buildings in the commercial sector. The 1992 CBECS is the fifth in a series conducted since 1979 by the Energy Information Administration. Approximately 6,600 commercial buildings were surveyed, representing the characteristics and energy consumption of 4.8 million commercial buildings and 67.9 billion square feet of commercial floorspace nationwide. Overall, the amount of commercial floorspace in the United States increased an average of 2.4 percent annually between 1989 and 1992, while the number of commercial buildings increased an average of 2.0 percent annually.

  11. 77 FR 3739 - Executive-led Aerospace and Defense Industry Trade Mission to Turkey-Notification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-25

    ... International Trade Administration Executive-led Aerospace and Defense Industry Trade Mission to Turkey... Commercial Service (CS) is organizing a U.S.--Turkey Aerospace and Defense Industry Trade Mission to Ankara... traveling to Turkey on their own, will enhance the companies' ability to secure meetings in Ankara...

  12. LED illuminator for a microdisplay projector

    NASA Astrophysics Data System (ADS)

    Magarill, Simon

    2012-10-01

    An illumination system for a microdisplay projector with a two-step imaging system is described here. In the first step, an imaging condenser creates an image of the LED at the color combiner entrance window. In the second step, we relay the image of the integrator exit window onto the micro-display. The illuminator demonstrates high collection efficiency, small footprint, and efficient mixing of light from RGB LEDs that provides required uniformity. A variety of approaches to collecting light emitted from LEDs of various types are compared, leading to the two-step design. A design example using a 0.55" diagonal DLP-based optical engine is presented with the following characteristics: Footprint: 3.9"x3.3"x2.0" (25.7 cubic inches) Light output: 338 white lumens Efficiency: 4.7 lm/watt

  13. LED-based NDIR natural gas analyzer

    NASA Astrophysics Data System (ADS)

    Fanchenko, Sergey; Baranov, Alexander; Savkin, Alexey; Sleptsov, Vladimir

    2016-03-01

    A new generation of the light-emitting diodes (LEDs) and photodiodes (PDs) was used recently to develop an open path non-dispersive infrared (NDIR) methane analyzer. The first open path detector prototype was constructed using LEDs for measurement and reference channels, accordingly, and first measurements for methane gas have been performed using optical paths of the order of several meters [3]. The natural gas consists of several first alkanes, mainly methane, and it is important to have a possibility of measuring all of them. In the present work we report the results of NDIR measurements for propane-butane mixture and new measurements of methane using LEDs for measurement and reference channels at 2300 and 1700 nm wavelengths, accordingly. The necessity of the double beam scheme is demonstrated and obtained results for methane and propane-butane mixture are compared.

  14. Laser and LED external teeth-bleaching

    NASA Astrophysics Data System (ADS)

    Zanin, Fatima A.; Brugnera, Aldo, Jr.; Marchesan, Melissa A.; Pecora, Jesus D.

    2004-09-01

    Teeth-bleaching is an initial phase in the reproduction of an aesthetic smile; thus, it is very important that the dentist knows how to diagnose the causes of color changes and indicate whitening before proposing dental treatment. Technological advances in teeth-whitening lead to the development of new techniques, improving comfort, security and decreasing time of execution: argon laser, diode Laser, LED whitening, xenon light whitening. The clearing agent used in all techniques, including home whitening, is hydrogen peroxide (H2O2) in different concentrations. In this study, the authors describe mechanisms of gel activation, the use of Laser and LED"s for teeth-bleaching, the importance of diagnosis and the comfort of the patient in in-office teeth-bleaching techniques.

  15. Zernike polynomials for photometric characterization of LEDs

    NASA Astrophysics Data System (ADS)

    Velázquez, J. L.; Ferrero, A.; Pons, A.; Campos, J.; Hernanz, M. L.

    2016-02-01

    We propose a method based on Zernike polynomials to characterize photometric quantities and descriptors of light emitting diodes (LEDs) from measurements of the angular distribution of the luminous intensity, such as total luminous flux, BA, inhomogeneity, anisotropy, direction of the optical axis and Lambertianity of the source. The performance of this method was experimentally tested for 18 high-power LEDs from different manufacturers and with different photometric characteristics. A small set of Zernike coefficients can be used to calculate all the mentioned photometric quantities and descriptors. For applications not requiring a great accuracy such as those of lighting design, the angular distribution of the luminous intensity of most of the studied LEDs can be interpolated with only two Zernike polynomials.

  16. Design of an Oximeter Based on LED-LED Configuration and FPGA Technology

    PubMed Central

    Stojanovic, Radovan; Karadaglic, Dejan

    2013-01-01

    A fully digital photoplethysmographic (PPG) sensor and actuator has been developed. The sensing circuit uses one Light Emitting Diode (LED) for emitting light into human tissue and one LED for detecting the reflectance light from human tissue. A Field Programmable Gate Array (FPGA) is used to control the LEDs and determine the PPG and Blood Oxygen Saturation (SpO2). The configurations with two LEDs and four LEDs are developed for measuring PPG signal and Blood Oxygen Saturation (SpO2). N-LEDs configuration is proposed for multichannel SpO2 measurements. The approach resulted in better spectral sensitivity, increased and adjustable resolution, reduced noise, small size, low cost and low power consumption. PMID:23291575

  17. Nano-lasers and nano-LEDs

    NASA Astrophysics Data System (ADS)

    Willander, Magnus

    2014-03-01

    One-dimensional nanostructures have been of great interest for photonic devices. In this talk I will give a review of the one-dimensional ZnO nanostructures for ultraviolet and visible regions. I will discuss earlier and last results regarding room temperature and low temperature spontaneous and stimulated emission. For lasers we will discuss both optically and electrically pumped lasers. For the LEDs particularly I will discuss the white light emission from LEDs. Substrates like graphene, paper, textile and semiconductors will be discussed. Finally, also results from other devices based on hybrid materials will be analyzed.

  18. LED luminaire with controlled light distribution

    NASA Astrophysics Data System (ADS)

    Schertler, Donald J.; Sales, Tasso R. M.; Chakmakjian, Stephen; Morris, G. Michael

    2006-08-01

    Unless coupled with some collimating optics, LED sources generally scatter with wide-angle Lambertian intensity profiles. The luminous output of such sources is not amenable to control and redistribution in an efficient manner. In this work we present the design and manufacturing of structures that are able to collect virtually all light from Lambertian LED sources and direct it towards diffusers engineered to illuminate specific regions of space in a controlled fashion. The resulting "engineered luminaire" is thus capable of highly efficient light control and can be applied to a wide variety of illumination situations such as general and architectural lighting.

  19. Nonintrusive Measurement Of Temperature Of LED Junction

    NASA Technical Reports Server (NTRS)

    Leidecker, Henning; Powers, Charles

    1991-01-01

    Temperature inferred from spectrum of emitted light. Method of determining temperature of junction based on two relevant characteristics of LED. Gap between valence and conduction electron-energy bands in LED material decreases with increasing temperature, causing wavelength of emitted photon to increase with temperature. Other, as temperature increases, non-radiative processes dissipate more of input electrical energy as heat and less as photons in band-gap wavelenth region; optical and quantum efficiencies decrease with increasing temperature. In principal, either characteristic alone used to determine temperature. However, desirable to use both to obtain indication of uncertainty.

  20. LED module with high index lens

    DOEpatents

    Bierhuizen, Serge J.; Wang, Nanze Patrick; Eng, Gregory W.; Sun, Decai; Wei, Yajun

    2016-07-05

    An array of housings with housing bodies and lenses is molded, or an array of housing bodies is molded and bonded with lenses to form an array of housings with housing bodies and lenses. Light-emitting diodes (LEDs) are attached to the housings in the array. An array of metal pads may be bonded to the back of the array or insert molded with the housing array to form bond pads on the back of the housings. The array is singulated to form individual LED modules.

  1. Industry Research and Recommendations for New Commercial Buildings

    SciTech Connect

    Hendron, B.; Leach, M.; Gregory, N.; Pless, S.; Selkowitz, S.; Matthew, P.

    2014-05-01

    Researchers evaluated industry needs and developed logic models to support possible future commercial new construction research and deployment efforts that could be led or supported by DOE's Commercial Building Integration program or other national initiatives. The authors believe that these recommendations support a proposed course of action from the current state of commercial building energy efficiency to a possible long-term goal of achieving significant market penetration of cost-effective NZE buildings in all building sectors and climates by 2030.

  2. Comparison of instructor-led versus peer-led debriefing in nursing students.

    PubMed

    Roh, Young Sook; Kelly, Michelle; Ha, Eun Ho

    2016-06-01

    Despite its widespread support, the most effective simulation-based debriefing method has little evidence to support its efficacy. In this study, we compared the effect of peer-led and instructor-led debriefing among nursing students. The study was conducted with a non-equivalent control group using a pretest-post-test design. A convenience sample of third-year nursing students was used for the study, where 65 students enrolled in a 2-week clinical placement rotation were randomly assigned to the instructor-led group or peer-led group. The quality of cardiopulmonary resuscitation skills, satisfaction with simulation, and quality of debriefing in the peer-led group were compared to those in the instructor-led group. Group differences at each testing interval were analyzed using independent t-test. Nursing students in the instructor-led debriefing group showed better subsequent cardiopulmonary resuscitation performance, more satisfaction with simulation experience, and higher debriefing scores compared to the peer-led group. From our study, instructor-led debriefing is an effective method in improving skills performance, inducing favorable satisfaction, and providing better quality of debriefing among nursing students. PMID:26833934

  3. High performance, LED powered, waveguide based total internal reflection microscopy

    NASA Astrophysics Data System (ADS)

    Ramachandran, Srinivasan; Cohen, Daniel A.; Quist, Arjan P.; Lal, Ratnesh

    2013-07-01

    Total internal reflection fluorescence (TIRF) microscopy is a rapidly expanding optical technique with excellent surface sensitivity and limited background fluorescence. Commercially available TIRF systems are either objective based that employ expensive special high numerical aperture (NA) objectives or prism based that restrict integrating other modalities of investigation for structure-function analysis. Both techniques result in uneven illumination of the field of view and require training and experience in optics. Here we describe a novel, inexpensive, LED powered, waveguide based TIRF system that could be used as an add-on module to any standard fluorescence microscope even with low NA objectives. This system requires no alignment, illuminates the entire field evenly, and allows switching between epifluorescence/TIRF/bright field modes without adjustments or objective replacements. The simple design allows integration with other imaging systems, including atomic force microscopy (AFM), for probing complex biological systems at their native nanoscale regimes.

  4. Enhancement of astaxanthin production using Haematococcus pluvialis with novel LED wavelength shift strategy.

    PubMed

    Xi, Tianqi; Kim, Dae Geun; Roh, Seong Woon; Choi, Jong-Soon; Choi, Yoon-E

    2016-07-01

    Haematococcus pluvialis is a green microalga of particular interest, since it is considered the best potential natural source of astaxanthin, which is widely used as an additive for natural pigmentation. In addition, astaxanthin has recently garnered commercial interest as a nutraceutical, cosmetic, and pharmaceutical. However, producing astaxanthin from H. pluvialis necessitates separation with distinctive culture conditions, dividing between the microalgae growth and the astaxanthin production stages. Light-emitting diodes (LEDs) have emerged as a replacement for traditional light sources, and LED applications are now rapidly expanding to multiple areas in fields such as biotechnology. However, further detail application into microalgae biotechnology remains limited. In this study, we have attempted to establish new protocols based on the specific wavelength of LEDs for the cultivation and production of astaxanthin using H. pluvialis. Specifically, we applied red LEDs for microalgae cell growth and then switched to blue LEDs to induce astaxanthin biosynthesis. The result showed that astaxanthin productions based on a wavelength shift from red to blue were significantly increased, compared to those with continuous illumination using red LEDs. Furthermore, additional increase of astaxanthin production was achieved with simultaneous application of exogenous carbon with blue LED illumination. Our approach based on the proper manipulation of LED wavelengths upon H. pluvialis cell stages will enable the improvement of biomass and enhance astaxanthin production using H. pluvialis. PMID:26860938

  5. Surgical retractor with RGB-WHITE LEDs

    NASA Astrophysics Data System (ADS)

    Shimada, Jun-ichi; Kato, Daishiro; Terauchi, Kunihiko; Itoh, Kazuhiro; Yanada, Masashi; Shimomura, Masanori; Tsuneduka, Hiroaki; Kawakami, Yoichi

    2008-02-01

    Sufficient lighting is sometimes required when surgeons watch the mediastinum through the 7x7cm thoracic window in video-assisted thoracoscopic (VATS) lobectomy. It is thus important to develop the "ultimately localized solid-statelighting" because the distance between the window and the surface of the lung is as short as 4-5 cm. Our new idea was to place the module composed of red, green and blue light emitting diodes (RGB LEDs) at the tip of the retractor. Compared to a conventional endoscopic lighting consisting of halogen lamp, this method has lead to the bright and shadowless illumination within the entire thoracic cavity since the white RGB LEDs are emitted unidirectionally from the cylinder-shaped camera component, moving the shadows from the surgical instruments to the side of the incision. It also should be noted that we found an effective principle for controlling the color rendering of each biomaterial through the synthesis of LED lighting spectra, by which the visual performance of surgeons can be coordinated. Therefore, we believe that "medical RGB LEDs" will contribute to the safe operation, and will be developed to a standard lighting system in clinical settings with bright surgical fields in the near future.

  6. LED structure with enhanced mirror reflectivity

    DOEpatents

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

    2014-04-01

    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.

  7. LED Lighting in a Performing Arts Building

    SciTech Connect

    Miller, N. J.; Kaye, S. M.; Coleman, P. M.; Wilkerson, A. M.; Perrin, T. E.; Sullivan, G. P.

    2014-07-31

    At the University of Florida in Gainesville, the DOE Solid-State Lighting GATEWAY program evaluated LED architectural and theatrical lighting in four academic/performance-related spaces within the Nadine McGuire Theatre + Dance Pavilion. Due to a wise choice of products and luminaire light distributions, the change brought significant quality improvements including improved controllability and color.

  8. How One Thing Led to Another.

    PubMed

    Weissman, Irving

    2016-05-20

    I started research in high school, experimenting on immunological tolerance to transplantation antigens. This led to studies of the thymus as the site of maturation of T cells, which led to the discovery, isolation, and clinical transplantation of purified hematopoietic stem cells (HSCs). The induction of immune tolerance with HSCs has led to isolation of other tissue-specific stem cells for regenerative medicine. Our studies of circulating competing germline stem cells in colonial protochordates led us to document competing HSCs. In human acute myelogenous leukemia we showed that all preleukemic mutations occur in HSCs, and determined their order; the final mutations occur in a multipotent progenitor derived from the preleukemic HSC clone. With these, we discovered that CD47 is an upregulated gene in all human cancers and is a "don't eat me" signal; blocking it with antibodies leads to cancer cell phagocytosis. CD47 is the first known gene common to all cancers and is a target for cancer immunotherapy. PMID:27168238

  9. Challenges and opportunities in LED based lighting

    NASA Astrophysics Data System (ADS)

    Panahi, Allen

    2013-05-01

    Solid state lighting technology has made great advances over the last decade and has become the technology of choice to displace legacy incandescent and as well as the more efficient fluorescent lights. While efficiencies have been improved and cost of the LEDs has been steadily lowered still many challenges exist in the thermal, electrical, optical, and packaging implementations.

  10. NASA Ames UV-LED Poster Overview

    NASA Technical Reports Server (NTRS)

    Jaroux, Belgacem Amar

    2015-01-01

    UV-LED is a small satellite technology demonstration payload being flown on the Saudisat-4 spacecraft that is demonstrating non-contacting charge control of an isolated or floating mass using new solid-state ultra-violet light emitting diodes (UV-LEDs). Integrated to the rest of the spacecraft and launched on a Dnepr in June 19, 2014, the project is a collaboration between the NASA Ames Research Center (ARC), Stanford University, and King Abdulaziz City for Science and Technology (KACST). Beginning with its commissioning in December, 2015, the data collected by UV-LED have validated a novel method of charge control that will improve the performance of drag-free spacecraft allowing for concurrent science collection during charge management operations as well as reduce the mass, power and volume required while increasing lifetime and reliability of a charge management subsystem. UV-LED continues to operate, exploring new concepts in non-contacting charge control and collecting data crucial to understanding the lifetime of ultra-violet light emitting diodes in space. These improvements are crucial to the success of ground breaking missions such as LISA and BBO, and demonstrates the ability of low cost small satellite missions to provide technological advances that far exceed mission costs.

  11. Determination of radiative current in LED's

    NASA Technical Reports Server (NTRS)

    Thomas, E. F.

    1976-01-01

    Directly measureable quantity of radiative output in LED's is total forward current. When applied forward voltage is below 1.05 V the forward current is primarily nonradiative and varies with forward voltage as exp(qV/2kT), when q is the charge, V is applied voltage, K is Boltzmann's constant, and T is operating temperature.

  12. Portrait of a Teacher-Led School

    ERIC Educational Resources Information Center

    Nazareno, Lori

    2013-01-01

    Imagine a school with no principal and with a leadership structure that holds teachers accountable for the learning of all students. About 50 such teacher-led schools currently operate across the United States, and this article tells the story of one of them. The Mathematics and Science Leadership Academy (MSLA) in Denver, Colorado, serves about…

  13. Child-Led Enquiry in Primary Science

    ERIC Educational Resources Information Center

    Dunlop, Lynda; Compton, Kirsty; Clarke, Linda; McKelvey-Martin, Valerie

    2015-01-01

    This research describes and evaluates the application of a child-led approach to scientific enquiry (the Community of Scientific Enquiry, CoSE) to children aged 8-11 (Key Stage 2) in Northern Ireland. Primary teachers were introduced to CoSE at a workshop and asked to evaluate its implementation with their class. Results from children (n = 364)…

  14. Neural networks for LED color control

    NASA Astrophysics Data System (ADS)

    Ashdown, Ian E.

    2004-01-01

    The design and implementation of an architectural dimming control for multicolor LED-based lighting fixtures is complicated by the need to maintain a consistent color balance under a wide variety of operating conditions. Factors to consider include nonlinear relationships between luminous flux intensity and drive current, junction temperature dependencies, LED manufacturing tolerances and binning parameters, device aging characteristics, variations in color sensor spectral responsitivities, and the approximations introduced by linear color space models. In this paper we formulate this problem as a nonlinear multidimensional function, where maintaining a consistent color balance is equivalent to determining the hyperplane representing constant chromaticity. To be useful for an architectural dimming control design, this determination must be made in real time as the lighting fixture intensity is adjusted. Further, the LED drive current must be continuously adjusted in response to color sensor inputs to maintain constant chromaticity for a given intensity setting. Neural networks are known to be universal approximators capable of representing any continuously differentiable bounded function. We therefore use a radial basis function neural network to represent the multidimensional function and provide the feedback signals needed to maintain constant chromaticity. The network can be trained on the factory floor using individual device measurements such as spectral radiant intensity and color sensor characteristics. This provides a flexible solution that is mostly independent of LED manufacturing tolerances and binning parameters.

  15. Student-Led Conferences: Students Taking Responsibility

    ERIC Educational Resources Information Center

    Nauss, Sherri A.

    2010-01-01

    One of the many challenges that face middle grade students, parents, and teachers is the student's lack of ownership of their academic achievements. Student-led conferences are a unique way to engage the student and the parent in the academic progress. Parents and teachers discuss the student's attitude toward the work, the student's work ethic in…

  16. Photomatrix LED therapy of extensive cutaneous pathology

    NASA Astrophysics Data System (ADS)

    Zharov, Vladimir P.; Menyaev, Yulian A.; Zharova, I. Z.; Leviev, Dmitry O.; Tsarev, V. N.; Sarantsev, V. P.; Krusic, Joze

    2000-05-01

    Standard sources of radiation have not sufficient efficiency at treating spatially extended pathology, especially when pathologic areas involve opposite sides of the human being's body or when they are uneven in shape. The typical examples of such pathology are extensive burns, oedema, inflammatory processes, infectious wounds, actinic keratosis, psoriasis, arthritis and neurological diseases. Superbright LEDs gathered in a matrix and grasping the area of irradiation are the most suitable sources of radiation. This article presents the result of investigation of the effectiveness of various types of the blue-to-infrared spectrum range LED array that allow irradiating a surface with an area from several cm2 to several thousand cm2 including the whole human being's body with the intensity varying from 1 to 100 mW/cm2. Besides the matrixes, composed of separate light diodes, modular systems with separate monolithic hybrid chips with a high density of positioning the sources of radiation are considered. The peculiarities and results of applying such systems to treat oedema, cancer, weight regulation, neurological diseases, different infections diseases in combination with PDT, stomatitis and paradontosis are analyzed. The parameters of the photomatrix LED for different spectral regions and different geometry from flat shape to semispherical and cylindrical are presented. The perspective combination photomatrix LED with another therapeutical devices including photovacuum and photomagnetic therapy are considered.

  17. Thermochromism in Commercial Products

    NASA Astrophysics Data System (ADS)

    White, Mary Anne; Leblanc, Monique

    1999-09-01

    Many commercial products change color with a change of temperature. How do they do it? The processes responsible for the two major categories of commercial thermochromic coloring agents are presented, along with a description of applications of thermochromic materials.

  18. LED solution for E14 candle lamp

    NASA Astrophysics Data System (ADS)

    Li, Yun; Liu, Ye; Boonekamp, Erik P.; Shi, Lei; Mei, Yi; Jiang, Tan; Guo, Qing; Wu, Huarong

    2009-08-01

    On a short to medium term, energy efficient retrofit LED products can offer an attractive solution for traditional lamps replacement in existing fixtures. To comply with user expectations, LED retrofit lamps should not only have the same mechanical interface to fit (socket and shape), but also have the similar light effect as the lamps they replace. The decorative lighting segment shows the best conditions to meet these requirements on short term. In 2008, Philips Lighting Shanghai started with the development of an LED candle lamp for the replacement of a 15W Candle shape (B35 E14) incandescent bulb, which is used in e.g. chandeliers. In this decorative application the main objective is not to generate as much light as possible, but the application requires the lamp to have a comparable look and, primarily, the same light effect as the incandescent candle lamp. This effect can be described as sparkling light, and it has to be directed sufficiently downwards (i.e., in the direction of the base of the lamp). These requirements leave very limited room for optics, electronics, mechanics and thermal design to play with in the small outline of this lamp. The main voltage AC LED concept is chosen to save the space for driver electronics. However the size of the AC LED is relatively big, which makes the optical design challenging. Several optical solutions to achieve the required light effect, to improve the optical efficiency, and to simplify the system are discussed. A novel prismatic lens has been developed which is capable of transforming the Lambertian light emission from typical high power LEDs into a butter-fly intensity distribution with the desired sparkling light effect. Thanks to this lens no reflecting chamber is needed, which improves the optical efficiency up to 70%, while maintaining the compact feature of the original optics. Together with advanced driver solution and thermal solution, the resulting LED candle lamp operates at 230V, consumes 1.8W, and

  19. NASA commercial programs

    NASA Technical Reports Server (NTRS)

    1988-01-01

    An expanded role for the U.S. private sector in America's space future has emerged as a key national objective, and NASA's Office of Commercial Programs is providing a focus for action. The Office supports new high technology commercial space ventures, the commercial application of existing aeronautics and space technology, and expanded commercial access to available NASA capabilities and services. The progress NASA has made in carrying out its new assignment is highlighted.

  20. Commercial Radio as Communication.

    ERIC Educational Resources Information Center

    Rothenbuhler, Eric W.

    1996-01-01

    Compares the day-to-day work routines of commercial radio with the principles of a theoretical communication model. Illuminates peculiarities of the conduct of communication by commercial radio. Discusses the application of theoretical models to the evaluation of practicing institutions. Offers assessments of commercial radio deriving from…

  1. Commercial Banking Industry Survey.

    ERIC Educational Resources Information Center

    Bright Horizons Children's Centers, Cambridge, MA.

    Work and family programs are becoming increasingly important in the commercial banking industry. The objective of this survey was to collect information and prepare a commercial banking industry profile on work and family programs. Fifty-nine top American commercial banks from the Fortune 500 list were invited to participate. Twenty-two…

  2. Commercialism in Schools.

    ERIC Educational Resources Information Center

    Larson, Kirstin

    2001-01-01

    This document gives voice to concerns raised by critics and supporters of commercialism in schools and provides brief descriptions of several important resources on this topic. "Commercial Activities in School" (U.S. General Accounting Office) reports on the nature and frequency of commercial activities in public schools, as well as the laws and…

  3. COMMERCIAL FOODS, MATHEMATICS - I.

    ERIC Educational Resources Information Center

    DORNFIELD, BLANCHE E.

    THE UNDERSTANDING AND MASTERY OF FUNDAMENTAL MATHEMATICS IS A NECESSARY PART OF COMMERCIAL FOODS WORK. THIS STUDENT HANDBOOK WAS DESIGNED TO ACCOMPANY A COMMERCIAL FOODS COURSE AT THE HIGH SCHOOL LEVEL FOR STUDENTS WITH APPROPRIATE APTITUDES AND COMMERCIAL FOOD SERVICE GOALS. THE MATERIAL, TESTED IN VARIOUS INTERESTED CLASSROOMS, WAS PREPARED BY…

  4. Sustainable LED Fluorescent Light Replacement Technology

    SciTech Connect

    2011-06-30

    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

  5. Phosphor-converted LEDs with low circadian action for outdoor lighting.

    PubMed

    Zabiliūtė, Akvilė; Vaicekauskas, Rimantas; Vitta, Pranciškus; Zukauskas, Artūras

    2014-02-01

    Dichromatic phosphor-converted (pc) light-emitting diodes (LEDs) with low circadian action are proposed for low-luminance photobiologically safe outdoor illumination. The LEDs feature the partial conversion of blue radiation in an orange phosphor with the resulting correlated color temperature in the "firelight" range of 1700-2500 K. The circadian action factor, which is the ratio of the biological efficacy of radiation due to the excitation of intrinsically photosensitive retinal ganglion cells to the mesopic luminous efficacy of radiation, is considerably lower than that of commercial white pc LEDs. The equivalent general color-rendering index estimated with regard to the reduced color-discrimination ability of human vision at low luminances has appropriate values in between those of common white pc LEDs and high-pressure sodium lamp. PMID:24487866

  6. Design of collimating system for LED source

    NASA Astrophysics Data System (ADS)

    Shen, Yanan; Huang, Yifan; Xing, Han

    2013-12-01

    Along with the development of semiconductor lighting technology, LED chip is widely used as the source of the glare flashlight. Collimating the light of the source and improving the utilization rate of light energy is crucial. The collimating lens is designed by the theory of geometrical optics and the theory of non-imaging optics. The small angle light from the source is collimated through the collimating lens surface, and the large angle light is collimated by the total reflection of the collimating lens. The collimating lens has a high light energy utilization and a good collimating performance. The collimation system is simulated and optimized in the Lighttools software. When the size of the LED chip is 1 mm*1 mm, the energy utilization rate of the collimating lens is more than 95%, and most lighting area radii are no more than 8 m when the illuminated plane is 500 m away from the light source.

  7. Laser and LED external teeth-bleaching

    NASA Astrophysics Data System (ADS)

    Zanin, Fatima; Brugnera, Aldo, Jr.; Marchesan, Melissa A.; Pecora, Jesus D.

    2004-05-01

    Teeth-bleaching is an initial phase in the reproduction of an aesthetic smile; thus, it is very important that the dentist knows how to diagnose the causes of color changes and indicate whitening before proposing dental treatment. Technological advances in teeth-whitening lead to the development of new techniques, improving comfort, security and decreasing time of execution: argon laser, diode laser, LED whitening, xenon light whitening. The clearing agent used in all techniques, including home whitening, is hydrogen peroxide (H2O2) in different concentrations. In this study, the authors describe mechanisms of gel activation, the use of Laser and LED's for teeth-bleaching, the importance of diagnosis and the comfort of the patient in in-office teeth-bleaching techniques.

  8. Business-led efforts to control costs.

    PubMed

    Kenkel, P J

    1991-07-29

    Business-led initiatives to compare medical quality and prices are becoming commonplace as employers seek ways to cap medical expenses. But employers are meeting with varying degrees of cooperation from hospitals. The tale of two cities' efforts to pry open the secrets of controlling costs provides a vivid contrast in the way purchasers have tried to solve the cost-containment puzzle. PMID:10111874

  9. Nurse led venesection: a quality improvement project

    PubMed Central

    Patel, Chandni; Morgan, Dafydd

    2015-01-01

    Venesection is a widely practised procedure, involving the removal of a unit of blood in order to treat haemochromatosis and polycythaemia. It is still well regarded due to a lack of better alternatives and a small side effect profile. At Barnet General Hospital, venesection has recently been a physician led service, unlike its neighbouring hospital at Chase Farm Hospital, which has a well run nurse led service. The current service being run at Barnet Hospital was beset with problems, including delays in service provision and discharge, using junior doctors who may not be comfortable with or have knowledge of pre and post procedure checks. Furthermore, the medical day treatment unit is comprised of highly skilled nurses. 100% of nursing staff felt comfortable gaining venous access, but none had any formal training. Following a practical tutorial, followed by formal teaching, the nurses now run the venesection service. This has been done at no cost to the hospital, has sped up discharges and this has subsequently led to the capacity of the unit to venesect patients to increase by 100%. PMID:26734402

  10. LED color mixing with diffractive structures

    NASA Astrophysics Data System (ADS)

    Bonenberger, Theresa; Baumgart, Jörg; Wendel, Simon; Neumann, Cornelius

    2013-03-01

    Lighting solutions with colored LEDs provide many opportunities for illumination. One of these opportunities is to create a color tunable light source. In this way different kinds of white light (color temperature) as well as discrete colors may be realized. This opens the field for applications as mood lighting. But there is always a spatial separation of the distinct LEDs that might get converted into an angular separation by any collimating optics. This angular separation causes such problems like color fringes and colored shadows that cannot be accepted in most applications. Conventional methods to solve these problems include e.g. mixing rods or dichroic filters. A new approach is the use of the dispersive effect of a diffractive structure to compensate the angular separation of the different colors. In this contribution the potential and limitations of diffractive structures in LED color mixing applications are discussed. Ray tracing simulations were performed to analyze such important parameters like efficiency, color performance and the cross section of the color mixing optics. New means for the estimation of color mixing performance were developed. A software tool makes it possible to detect the color distribution within ray trace data and it provides a quality factor to estimate the color mixing performance. It can be shown that the spectral band width has a large influence on the mixing process. Ray tracing simulations are compared with results of an experimental setup such that both measured as well as simulated data is presented.

  11. LED downlights with non-circular spots

    NASA Astrophysics Data System (ADS)

    Parkyn, William A.; Pelka, David G.

    2005-09-01

    The ubiquitous downlight inhabits our ceilings by the millions. Hot, inefficient, and electrically wasteful, it is next in line for replacement by the latest high-brightness, high-efficacy white LEDs. The conventional downlight configuration of a large incandescent spotlight in a low-cost, ceiling-recessed metal can, represents the culmination of old technology, fated never to improve significantly. Incandescent downlights add greatly both to direct and indirect electrical consumption, with the lamps requiring relatively frequent replacement. The small size of LED emitters means small optical elements can produce much higher-quality beams than incandescent spotlight-lamps can produce. Herein we introduce compact high-luminosity LED downlights with lenses that deliver uniform illumination to delimited targets such as tables. One version utilizes circular lenses and micro-diffuser films to deliver square outputs. The other uses lenses cut to the target shape. In particular, one of these lenses is the first to offer a semicircular spot suitable for gambling tables.

  12. New design tools for LED headlamps

    NASA Astrophysics Data System (ADS)

    Domhardt, André; Rohlfing, Udo; Weingaertner, Simon; Klinger, Karsten; Kooß, Dieter; Manz, Karl; Lemmer, Uli

    2008-04-01

    The automotive lighting technology is in considerable progress due to new components, e.g., High-Power-LEDs and light guides, and new sophisticated production techniques. Furthermore, great importance is being attached to the appearance of front and tail lamps. White High-Power-LEDs have reached a development stage that affords its reasonable application to low beam headlamps. This challenging illumination function requires sophisticated design techniques in order to preserve the advantages associated with this source type. Thus, high efficiency and stylish appearance have to be reconciled, e.g., with the use of freeform surfaces. Beside the demands from manufacturers and customers, car lamps have to meet several regulations (ECE, SAE, etc.). This contribution describes the illumination design of a LED-based low beam headlamp using advanced mathematical methods, e.g., 3D-Tailoring, automatic optimization, and Virtually Reflecting/Refracting Surfaces (VRS). We propose this new surface type with non conventional reflection/refraction properties as an advantageous design tool for the first layout and for automatic optimization, as well. For efficiency reasons, special attention will be paid to the creation of the cut-off line without using additional stops.

  13. Investigation of the spectral properties of LED-based MR16 bulbs for general illumination

    NASA Astrophysics Data System (ADS)

    Brown, David F.; Nicol, David B.; Ferguson, Ian T.

    2005-11-01

    The spectral properties of commercially available halogen and LED-based MR16s were investigated. The metrics used to characterize the MR16s include the total luminous flux (TLF), correlated color temperature (CCT), color-rendering index (CRI), angular variation of CCT, and luminous efficacy. The halogen MR16s were included as a baseline for comparison with LED-based MR16s. Seven LED-based MR16s were investigated, including three constructed from 5-mm LEDs, and four constructed from high-power devices based on a larger die. It is shown that MR16s constructed from white LEDs are not suitable as a direct replacement for existing alternatives at this time, due to their low power efficiency and poor TLF. MR16s constructed with a single phosphor also have poor CRIs and undesirable CCTs. An MR16 with an extra phosphor in the red region of the spectrum shows improvement in CRI and a lower CCT than the other LED-based MR16s. All of the LED-based MR16s had a variation of CCT that was larger than those of the halogen devices.

  14. BiliLED low cost neonatal phototherapy, from prototype to industry

    NASA Astrophysics Data System (ADS)

    Geido, Daniel; Failache, Horacio; Simini, Franco

    2007-11-01

    BiliLED is a phototherapy instrument designed to reduce bilirrubin blood rates in new born babies with jaundice. The light source is centred at 470 nm with a bandwidth of 35 nm and includes a matrix of 196 (14×14) InGaN LEDs. The optical elements are designed to maximize the light intensity useful for treatment, with a small number of LEDs in a compact and low cost unit. The optic array is such that every LED illuminates all the treatment area, which ensures redundancy and, thus, a high reliability not to be found in single-lamp instruments. Thermal dissipation and cost of BiliLED are both an order-of-magnitude smaller than conventional therapy lamps. BiliLED adjusts coetaneous irradiation with a feedback loop to compensate the loss or aging of LEDs achieving a calibrated light source for over a decade of use. A clinical trial in 20 hyperbilirrubinaemia patients shows 16% bilirrubin degradation within 24 hours of treatment, higher than most lamp phototherapy instruments. The steps from prototype to commercial model are described.

  15. World commercial aircraft accidents

    SciTech Connect

    Kimura, C.Y.

    1993-01-01

    This report is a compilation of all accidents world-wide involving aircraft in commercial service which resulted in the loss of the airframe or one or more fatality, or both. This information has been gathered in order to present a complete inventory of commercial aircraft accidents. Events involving military action, sabotage, terrorist bombings, hijackings, suicides, and industrial ground accidents are included within this list. Included are: accidents involving world commercial jet aircraft, world commercial turboprop aircraft, world commercial pistonprop aircraft with four or more engines and world commercial pistonprop aircraft with two or three engines from 1946 to 1992. Each accident is presented with information in the following categories: date of the accident, airline and its flight numbers, type of flight, type of aircraft, aircraft registration number, construction number/manufacturers serial number, aircraft damage, accident flight phase, accident location, number of fatalities, number of occupants, cause, remarks, or description (brief) of the accident, and finally references used. The sixth chapter presents a summary of the world commercial aircraft accidents by major aircraft class (e.g. jet, turboprop, and pistonprop) and by flight phase. The seventh chapter presents several special studies including a list of world commercial aircraft accidents for all aircraft types with 100 or more fatalities in order of decreasing number of fatalities, a list of collision accidents involving commercial aircrafts, and a list of world commercial aircraft accidents for all aircraft types involving military action, sabotage, terrorist bombings, and hijackings.

  16. Investigation of phosphor-LED lamp for real-time half-duplex wireless VLC system

    NASA Astrophysics Data System (ADS)

    Yeh, Chien-Hung; Chow, Chi-Wai; Chen, Hsing-Yu; Liu, Yen-Liang; Hsu, Dar-Zu

    2016-06-01

    In this investigation, a 71.3 to 148.4 Mbit s‑1 white phosphor-LED visible light communication (VLC) system is proposed and demonstrated under the practical transmission length of 140 to 210 cm. Here, a commercial white-light LED lamp with five cascaded phosphor-LED chips is utilized for illumination and communication simultaneously. In the measurement, we utilize the optical orthogonal frequency division multiplexing quadrature amplitude modulation (OFDM-QAM) with bit-loading algorithm and propose an optimal bias-tee circuit design to improve the modulation bandwidth from 1 MHz to 27 MHz. Moreover, a blue optical filter is not used on the client side. Finally, to realize and demonstrate the real-time transmission performance in the proposed LED VLC system, a commercial OFDM-based digital signal processor (DSP) chip is utilized on the LED lighting side and client side, respectively. Hence, the proposed real-time half-duplex VLC transmission could achieve the 70 Mbit s‑1 downstream and upstream data throughputs, under a practical transmission length of 200 cm.

  17. Influences of colorful LED emissions on spectrophotometric properties of a LED based white light source

    NASA Astrophysics Data System (ADS)

    Sametoglu, F.; Celikel, O.

    2011-05-01

    A LED based white light source (WLS) is designed and constructed to determine the color characteristics of the samples having specular and diffuse reflectance properties at the standard measurement conditions of 0/45 and d/8. The light source is composed of high power cool white and ultraviolet light emitting diodes (LEDs) which are operable in adjustable current levels. In order to combine the light beams emerging from two LED sources, a 1x2 fiber optic combiner is used. Optical characterizations of the light source designed and influences of several colorful LEDs called Royal-Blue, Blue, Cyan, Green, Amber, Red-Orange and Red on spectrophotometric properties of the light source are investigated.

  18. Lunar Commercialization Workshop

    NASA Technical Reports Server (NTRS)

    Martin, Gary L.

    2008-01-01

    This slide presentation describes the goals and rules of the workshop on Lunar Commercialization. The goal of the workshop is to explore the viability of using public-private partnerships to open the new space frontier. The bulk of the workshop was a team competition to create a innovative business plan for the commercialization of the moon. The public private partnership concept is reviewed, and the open architecture as an infrastructure for potential external cooperation. Some possible lunar commercialization elements are reviewed.

  19. Child-led enquiry in primary science

    PubMed Central

    Dunlop, Lynda; Compton, Kirsty; Clarke, Linda; McKelvey-Martin, Valerie

    2015-01-01

    This research describes and evaluates the application of a child-led approach to scientific enquiry (the Community of Scientific Enquiry, CoSE) to children aged 8–11 (Key Stage 2) in Northern Ireland. Primary teachers were introduced to CoSE at a workshop and asked to evaluate its implementation with their class. Results from children (n = 364) and teachers (n = 19) found that CoSE engaged children with their science learning, and also developed confidence and oracy. However, teachers require more experience developing facilitation skills and in fitting science into a thematic teaching unit. PMID:27152060

  20. Wheat Under LED's (Light Emitting Diodes)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Astroculture is a suite of technologies used to produce and maintain a closed controlled environment for plant growth. The two most recent missions supported growth of potato, dwarf wheat, and mustard plants, and provided scientists with the first opportunity to conduct true plant research in space. Light emitting diodes have particular usefulness for plant growth lighting because they emit a much smaller amount of radiant heat than do conventional lighting sources and because they have potential of directing a higher percentage of the emitted light onto plants surfaces. Furthermore, the high output LED's have emissions in the 600-700 nm waveband, which is of highest efficiency for photosynthesis by plants.

  1. Multiple LED camera for dynamic photoelasticity

    NASA Astrophysics Data System (ADS)

    Asundi, A.; Sajan, M. R.

    1995-05-01

    Dynamic photoelasticity involves the high-speed recording of rapidly moving fringe patterns in synchronization with loading. Cranz Schardin cameras are routinely utilized in the recording of dynamic photoelastic patterns. There are no moving components in these cameras, making the setup simple and attractive. A multiple LED camera based on the Cranz Schardin format is presented. High-speed instant polaroid film is used for recording the photoelastic fringes. Low cost, simplicity in the experimental setup, and rapid repeatability are the advantages of the camera.

  2. Tobacco prevention advertising: lessons from the commercial world.

    PubMed

    Rust, L

    1999-01-01

    This paper presents observations on how commercial TV advertising usually works with young people, discusses the special circumstances using advertising as a smoking prevention tool, and suggests research to guide future efforts. It is important for prevention efforts to recognize that in everyday life many young people are not systematic decision-makers; their intentions are extremely volatile and context-dependent, and they are highly spontaneous. So trying to change their smoking risk status with a TV ad that affects their conscious intentions toward smoking may not impact how they react when someone offers to share a cigarette with them behind the garage--even if it affects how they answer a "Do you think you'll ever take up smoking?" question right after seeing the ad. Advertising is good at getting consumers to focus on products--either in creating new brands, or in keeping familiar brands foremost in mind. Advertising is also good at providing models of concrete behaviors for people to imitate. Prevention efforts need to use advertising for what it is good at, and by and large this means being very concrete. Ultimately, for research to contribute to better prevention advertising, it needs to give the people who actually create that advertising a set of vivid, compelling images of who it is they are trying to reach and what it is that moves them. Some research methods which, when done properly, can serve this function are focus groups, anthropological studies, psychographic segmentations, moment-by-moment observational measurement, improved copy-testing methodology, and grounded-theory development. PMID:11072410

  3. Desktop autostereoscopic display using compact LED projector

    NASA Astrophysics Data System (ADS)

    Kaneko, Hiroki; Ohshima, Tetsuya; Ebina, Osamu; Arimoto, Akira

    2003-05-01

    A stereoscopic display using a curved directional reflection (CDR) screen and projectors is a promising approach towards realizing an immersive three-dimensional (3D) display system. The CDR screen consists of a corner reflective mirror sheet for horizontal focusing and an anisotropic diffuser sheet for vertical diffusion. The CDR 3D display can provide bright and large images without the need for special glasses. In this paper, we introduce this immersive 3D display technique onto the desktop display. To realize this concept, we have developed the compact projectors with light emitting diode (LED) light sources and a liquid crystal on silicon (LCOS). These have allowed the realization of 65 mm width projectors that are able to be put side by side at the interocular distance. The efficient optical system of an LED array as area-light-sources combined with an ultra high gain (>100) CDR screen have allowed for a desktop autostereoscopic display whose luminance is more than 100 cd/m2 with only 9 W power consumption. This system provides immersive 3D images for only the observer and keeps his privacy.

  4. Dimmable VLC demonstration systems based on LED

    NASA Astrophysics Data System (ADS)

    Kim, Hyeon-Cheol; Lee, Seong-Su; Jung, Sung-Yoon

    2012-12-01

    Recently, there have been many attempts to converge LED with IT technology. Among them, Visible Light Communication (VLC), which is the convergence of illumination and communication, has emerged. In VLC system, both lighting and communication can be simultaneously implemented. By considering both terms together, VPPM(Variable Pulse Position Modulation) modulation scheme is proposed by the IEEE 802.15.7 standard group. It uses binary PPM (Pulse Position Modulation) for communication and PWM (Pulse Width Modulation) for dimming control. In this paper, we introduce the implementation of VLC demonstration system based on VPPM modulation scheme. By changing the pulse width of VPPM signal, we can support 25%, 50% and 75% dimming. In addition, our VLC demonstration system provides a new power system using solar cell. By receiving the VPPM modulated visible light signal in the receiver end, we turn on the receiver power and start the system operation to decode the transmitted signal. By using ATmega128 8bit Micro Controller Unit (MCU) by ATMEL and Q3 XLamp XP-E LEDs of Cree, our system provides about 2kbps data rate with 2.5kHz optical rate in more than 30cm distance. By implementing DM S/W, we show the bit error rate (BER) and achievable data rate (ADR) of our demonstration system.

  5. LED context lighting system in residential areas.

    PubMed

    Kwon, Sook-Youn; Im, Kyoung-Mi; Lim, Jae-Hyun

    2014-01-01

    As issues of environment and energy draw keen interest around the globe due to such problems as global warming and the energy crisis, LED with high optical efficiency is brought to the fore as the next generation lighting. In addition, as the national income level gets higher and life expectancy is extended, interest in the enhancement of life quality is increasing. Accordingly, the trend of lightings is changing from mere adjustment of light intensity to system lighting in order to enhance the quality of one's life as well as reduce energy consumption. Thus, this study aims to design LED context lighting system that automatically recognizes the location and acts of a user in residential areas and creates an appropriate lighting environment. The proposed system designed in this study includes three types of processing: first, the creation of a lighting environment index suitable for the user's surroundings and lighting control scenarios and second, it measures and analyzes the optical characteristics that change depending on the dimming control of lighting and applies them to the index. Lastly, it adopts PIR, piezoelectric, and power sensor to grasp the location and acts of the user and create a lighting environment suitable for the current context. PMID:25101325

  6. UV LED lighting for automated crystal centring

    PubMed Central

    Chavas, Leonard M. G.; Yamada, Yusuke; Hiraki, Masahiko; Igarashi, Noriyuki; Matsugaki, Naohiro; Wakatsuki, Soichi

    2011-01-01

    A direct outcome of the exponential growth of macromolecular crystallography is the continuously increasing demand for synchrotron beam time, both from academic and industrial users. As more and more projects entail screening a profusion of sample crystals, fully automated procedures at every level of the experiments are being implemented at all synchrotron facilities. One of the major obstacles to achieving such automation lies in the sample recognition and centring in the X-ray beam. The capacity of UV light to specifically react with aromatic residues present in proteins or with DNA base pairs is at the basis of UV-assisted crystal centring. Although very efficient, a well known side effect of illuminating biological samples with strong UV sources is the damage induced on the irradiated samples. In the present study the effectiveness of a softer UV light for crystal centring by taking advantage of low-power light-emitting diode (LED) sources has been investigated. The use of UV LEDs represents a low-cost solution for crystal centring with high specificity. PMID:21169682

  7. LED Context Lighting System in Residential Areas

    PubMed Central

    Im, Kyoung-Mi

    2014-01-01

    As issues of environment and energy draw keen interest around the globe due to such problems as global warming and the energy crisis, LED with high optical efficiency is brought to the fore as the next generation lighting. In addition, as the national income level gets higher and life expectancy is extended, interest in the enhancement of life quality is increasing. Accordingly, the trend of lightings is changing from mere adjustment of light intensity to system lighting in order to enhance the quality of one's life as well as reduce energy consumption. Thus, this study aims to design LED context lighting system that automatically recognizes the location and acts of a user in residential areas and creates an appropriate lighting environment. The proposed system designed in this study includes three types of processing: first, the creation of a lighting environment index suitable for the user's surroundings and lighting control scenarios and second, it measures and analyzes the optical characteristics that change depending on the dimming control of lighting and applies them to the index. Lastly, it adopts PIR, piezoelectric, and power sensor to grasp the location and acts of the user and create a lighting environment suitable for the current context. PMID:25101325

  8. Studying Light Color using White LED Lighting

    NASA Astrophysics Data System (ADS)

    Yamagishi, Misako; Yamaba, Kazuo; Nagata, Manori; Kubo, Chiho; Nokura, Kunihiro

    Recently, white Light Emitting Diodes (LEDs) are receiving attention worldwide as new lighting devices. This study examined effects of a lighting application on performance using white LEDs. The light color—the correlated color temperature (CCT) —was assessed. It affected to psychological states and physiological conditions. Three CCT conditions were respectively set for the experiment: 2500 K, 5000 K, and 8200 K. In all, 20 younger subjects (20-30 years old), 15 middle-aged to elderly subjects (45-60 years old) and 12 elderly subjects (over 65 years-old) participated. They were presented a Numerical Verification (NV) task for performance measurement. The psychological states on performance were evaluated using the lighting assessment questionnaire. The physiological conditions were recorded using an electrocardiograph. Results show that the effects of CCT differ among age groups. Especially, the performance of younger subjects might differ from CCT conditions; elderly subjects are affected by CCT condition because of their visual acuity or response to contrast of objects.

  9. Freeform reflector design for LED street lighting

    NASA Astrophysics Data System (ADS)

    Li, Chen; Schreiber, Peter; Walkling, Andreas; Schierz, Christoph; Schwede, Maik; Gühne, Volker

    2011-10-01

    Faceted freeform reflectors were designed for intelligent street lighting with LED cluster arrays for main traffic roads. Special attention was paid to achieve highly efficient illumination on both wet and dry road surfaces. CIE reflection tables W4 and C2 were applied in the simulation for these two conditions, respectively. The reflector design started with plane facets, then - to avoid artifacts from the images of the individual LEDs - plane facets were replaced with cylindrical facets. To get even more flexibility for the design and optimization, freeform facets were employed, modeled by extruding two different conic curves together. Besides of achieving well-proportioned road luminance distribution, the basic shapes of the reflectors were formed to control stray light caused by multiple reflections within the reflector and by reflection of light from neighbor clusters within the cluster array. The merit functions include useful transmission of light to the road as well as overall and lengthwise uniformity according to road illumination standards. Due to the large amount of variables, the optimization was carried out sequentially facet by facet. The design loops included compromising with manufacturing limitations for plastics molding and thorough analysis of conformity with DIN EN 13201 standards for ME road lighting classes. The calculated reflector profiles are realized by plastic injection molding.

  10. Commercial fertilizers 1991

    SciTech Connect

    Hargett, N.L.; Berry, J.T.; Montgomery, M.H.

    1991-12-01

    This document contains consumption data for commercial fertilizers in the USA for 1991. Graphical information on the consumption by class is given for the nation. State by state data for consumption of several types of commercial fertilizers are presented. Only numerical data is included.

  11. Commercialism in Intercollegiate Athletics.

    ERIC Educational Resources Information Center

    Delany, James E.

    1997-01-01

    Outlines the history of intercollegiate athletics and the evolution of commercialization in college sports, particularly through television. Argues that few Division I programs could be self-sufficient; the issue is the degree to which sports are commercialized for revenue, and the challenge to balance schools' needs, private sector interests, and…

  12. Commercialism@Schools.

    ERIC Educational Resources Information Center

    Molnar, Alex; Morales, Jennifer

    2000-01-01

    The Center for the Analysis of Commercialism in Schools found that the number of press citations from 1990 to 2000 discussing seven types of commercializing activities (program sponsorship, exclusive agreements, incentive programs, appropriation of space, sponsored educational materials, electronic marketing, privatization, and fund raising)…

  13. EDITORIAL: LED light sources (light for the future) LED light sources (light for the future)

    NASA Astrophysics Data System (ADS)

    Grandjean, N.

    2010-09-01

    Generating white light from electricity with maximum efficacy has been a long quest since the first incandescent lamp was invented by Edison at the end of the 19th century. Nowadays, semiconductors are making reality the holy grail of converting electrons into photons with 100% efficiency and with colours that can be mixed for white light illumination. The revolution in solid-state lighting (SSL) dates to 1994 when Nakamura reported the first high-brightness blue LED based on GaN semiconductors. Then, white light was produced by simply combining a blue dye with a yellow phosphor. After more than a decade of intensive research the performance of white LEDs is quite impressive, beating by far the luminous efficacy of compact fluorescent lamps. We are likely close to replacing our current lighting devices by SSL lamps. However, there are still technological and fabrication cost issues that could delay large market penetration of white LEDs. Interestingly, SSL may create novel ways of using light that could potentially limit electricity saving. Whatever the impact of SSL, it will be significant on our daily life. The purpose of this special cluster issue is to produce a snapshot of the current situation of SSL from different viewing angles. In an introductory paper, Tsao and co-workers from Sandia National Laboratories, present an energy-economics perspective of SSL considering societal changes and SSL technology evolution. In a second article, Narukawa et al working at Nichia Corporation—the pioneer and still the leading company in SSL—describe the state of the art of current research products. They demonstrate record performance with white LEDs exhibiting luminous efficacy of 183 lm W-1 at high-current injection. Then, a series of topical papers discuss in detail various aspects of the physics and technology of white LEDs Carrier localization in InGaN quantum wells has been considered the key to white LEDs' success despite the huge density of defects. A

  14. Technology Transfer and Commercialization

    NASA Technical Reports Server (NTRS)

    Martin, Katherine; Chapman, Diane; Giffith, Melanie; Molnar, Darwin

    2001-01-01

    During concurrent sessions for Materials and Structures for High Performance and Emissions Reduction, the UEET Intellectual Property Officer and the Technology Commercialization Specialist will discuss the UEET Technology Transfer and Commercialization goals and efforts. This will include a review of the Technology Commercialization Plan for UEET and what UEET personnel are asked to do to further the goals of the Plan. The major goal of the Plan is to define methods for how UEET assets can best be infused into industry. The National Technology Transfer Center will conduct a summary of its efforts in assessing UEET technologies in the areas of materials and emissions reduction for commercial potential. NTTC is assisting us in completing an inventory and prioritization by commercialization potential. This will result in increased exposure of UEET capabilities to the private sector. The session will include audience solicitation of additional commercializable technologies.

  15. Lens of controllable optical field with thin film metallic glasses for UV-LEDs.

    PubMed

    Pan, C T; Chen, Y C; Lin, Po-Hung; Hsieh, C C; Hsu, F T; Lin, Po-Hsun; Chang, C M; Hsu, J H; Huang, J C

    2014-06-16

    In the exposure process of photolithography, a free-form lens is designed and fabricated for UV-LED (Ultraviolet Light-Emitting Diode). Thin film metallic glasses (TFMG) are adopted as UV reflection layers to enhance the irradiance and uniformity. The Polydimethylsiloxane (PDMS) with high transmittance is used as the lens material. The 3-D fast printing is attempted to make the mold of the lens. The results show that the average irradiance can be enhanced by 6.5~6.7%, and high uniformity of 85~86% can be obtained. Exposure on commercial thick photoresist using this UV-LED system shows 3~5% dimensional deviation, lower than the 6~8% deviation for commercial mercury lamp system. This current system shows promising potential to replace the conventional mercury exposure systems. PMID:24977538

  16. Characterising and testing deep UV LEDs for use in space applications

    NASA Astrophysics Data System (ADS)

    Hollington, D.; Baird, J. T.; Sumner, T. J.; Wass, P. J.

    2015-12-01

    Deep ultraviolet (DUV) light sources are used to neutralise isolated test masses in highly sensitive space-based gravitational experiments. An example is the LISA Pathfinder charge management system, which uses low-pressure mercury lamps. A future gravitational-wave observatory such as eLISA will use UV light-emitting diodes (UV LEDs), which offer numerous advantages over traditional discharge lamps. Such devices have limited space heritage but are now available from a number of commercial suppliers. Here we report on a test campaign that was carried out to quantify the general properties of three types of commercially available UV LEDs and demonstrate their suitability for use in space. Testing included general electrical and UV output power measurements, spectral stability, pulsed performance and temperature dependence, as well as thermal vacuum, radiation and vibration survivability.

  17. Fluorescent Brighteners as Visible LED-Light Sensitive Photoinitiators for Free Radical Photopolymerizations.

    PubMed

    Zuo, Xiaoling; Morlet-Savary, Fabrice; Graff, Bernadette; Blanchard, Nicolas; Goddard, Jean-Philippe; Lalevée, Jacques

    2016-05-01

    The photochemical and electrochemical investigations of commercially available, safe, and cheap fluorescent brighteners, namely, triazinylstilbene (commercial name: fluorescent brightener 28) and 2,5-bis(5-tert-butyl-benzoxazol-2-yl)thiophene, as well as their original use as photoinitiators of polymerization upon light emitting diode (LED) irradiation are reported. Remarkably, their excellent near-UV-visible absorption properties combined with outstanding fluorescent properties allow them to act as high-performance photoinitiators when used in combination with diaryliodonium salt. These two-component photoinitiating systems can be employed for free radical polymerizations of acrylate. In addition, this brightener-initiated photopolymerization is able to overcome oxygen inhibition even upon irradiation with low LED light intensity. The underlying photochemical mechanisms are investigated by electron-spin resonance-spin trapping, fluorescence, cyclic voltammetry, and steady-state photolysis techniques. PMID:27072016

  18. Studies and issues of thin-GaN LED process

    NASA Astrophysics Data System (ADS)

    Chen, P. H.; Lin, C. L.; Lin, Y. H.; Chou, P. K.; Liu, C. Y.

    2007-09-01

    A newly developed thin-GaN LED structure has shown great advantages over traditional LED schemes in the lighting efficiency performance. Yet, in the fabrication process of thin-GaN LED chip, several processes still remain to be optimized. In this paper, the process issues of the promising thin-GaN LED chip will be discussed.

  19. Spectral optimization of the color temperature tunable white light-emitting diode (LED) cluster consisting of direct-emission blue and red LEDs and a diphosphor conversion LED.

    PubMed

    Zhong, Ping; He, Guoxing; Zhang, Minhao

    2012-09-10

    The correlated color temperature (CCT) tunable white-light LED cluster, which consists of direct-emission blue and red LEDs as well as phosphor-conversion (PC) LEDs packaged by combining green and orange phosphors with a blue LED die, has been obtained by nonlinear program for maximizing luminous efficacy (LE) of radiation (LER) under conditions of both color rendering index (CRI) and special CRI of R9 for strong red above 90 at CCTs of 2700 K to 6500 K. The optimal peak wavelengths of blue LED, red LED, blue LED die, green and orange phosphors are 465 nm, 628 nm, 452 nm, 530 nm and 586 nm, respectively. The real CCT tunable PC/red/blue LED cluster with CRIs of 90~96, R9s of 90~96, CQSs of 89~94, LERs of 303~358 lm/W, and LEs of 105~119 lm/W has been realized at CCTs of 2722 K to 6464 K. The deviation of the peak wavelength should be less than ± 5 nm for blue LED die, ± 1 nm for red LED, and ± 2 nm for blue LED to achieve the PC/R/B LED cluster with high optical performance. PMID:23037535

  20. Spatially Resolved Thermal Analysis of High Power LEDs Using Thermoreflectance Microscopy

    NASA Astrophysics Data System (ADS)

    Wang, Hexuan; Al-Hemyari, Kadhair; Yan, Susu; Summers, Joseph; Hudgings, Janice

    2012-02-01

    The efficiency, reliability, and lifetime of high power light emitting diodes (LEDs) depend critically on their operating temperature. The lateral temperature distribution is of particular importance with large area, high power LEDs as defects related to overheating in high power LEDs usually occur at a high rate at the surface. In this work, we present the use of lock-in thermoreflectance imaging to measure the spatially resolved surface thermal distribution of operating LEDs. This non-invasive thermography technique offers high spatial and thermal resolutions. We show that results of thermoreflectance surface temperature are quantitatively consistent with temperature measurements obtained using forward voltage bias and wavelength shift techniques. We demonstrate the power of spatially resolved thermoreflectance by imaging the highly non-uniform surface temperature distribution of an operating LED at high electrical bias power. We conclude that the non-uniform surface temperature distribution is resulted from non-uniformly distributed inject current and overheating at the contacts. We also investigate the thermal impact of encapsulating commercial LEDs with a plastic lens and silicone epoxy.

  1. Effects of pitch and shape for diffraction grating in LED fog lamp

    NASA Astrophysics Data System (ADS)

    Chen, Hsi-Chao; Lin, Jun-Yu; Wu, Jih-Huah; Ma, Shih-Hsin; Yang, Chi-Hao

    2011-10-01

    The characteristics of light-emitting diodes (LEDs) that make them energy-efficient and long-lasting light source for general illumination have attracted a great attention from the lighting industry and commercial market. As everyone know LEDs have the advantages of environmental protection, long lifetime, fast response time (μs), low voltage and good mechanical properties. Their high luminance and the wide region of the dominant wavelengths within the entire visible spectrum mean that people have high anticipations for the applications of LEDs. The output lighting from reflector in the traditional fog lamp was required to fit the standard of the ECE R19 F3 regulation. Therefore, this study investigated the effects of pitch and angle for a diffraction grating in LED fog lamp. The light pattern of fog lamp must be satisfied ECE regulations, so a design of diffraction grating to shift down the lighting was required. There are three LEDs (Cree XLamp XPE LEDs) as the light source in the fog lamp for the illumination efficiency. Then, an optimal simulation of diffraction grating was done for the pitch and angle of the diffraction grating at the test distance of 25 meters. The best pitch and angle was 2mm and 60 degree for the grating shape of wedge type.

  2. RGB color sensor implemented with LEDs

    NASA Astrophysics Data System (ADS)

    Filoteo-Razo, J. D.; Estudillo-Ayala, J. M.; Hernández-Garcia, J. C.; Trejo-Durán, M.; Muñoz-Lopez, A.; Jauregui-Vázquez, D.; Rojas-Laguna, R.

    2015-09-01

    This paper presents the design and implementation of an optical sensor to detect color changes in fruit by means of white light reflection to measure fruit ripeness in industrial and agricultural applications. The system consists of a LED RGB array including photodetectors, a power source and plastic optic fiber (POF). By means of Labview ® graphic interface we can control the power emission of the diodes digitally mixing the colors at different intensities until we achieve white light to be used as a source for the color sensor. We used an ATmega2560 microcontroller as a data collection device to monitor the colors obtained and to show them as color models using Matlab ®. We show results from tests conducted using two guava samples, observing the evolution of the color change on the fruit skin until they became overripe.

  3. Scandium oxide antireflection coatings for superluminescent LEDs

    NASA Technical Reports Server (NTRS)

    Ladany, I.; Zanzucchi, P. J.; Andrews, J. T.; Kane, J.; Depiano, E.

    1986-01-01

    For an employment of laser diodes as superluminescent LEDs (SLDs) or amplifiers, the facets of the diodes must be coated with antireflection films. In the work reported, scandium oxide was evaporated from an e-beam source onto Supersil II fused silica substrates. The obtained samples were used for measurements of absorption and reflectivity. Results of index measurements on e-beam evaporated films are presented. It is shown that excellent coatings with reflectivities of 0.00025 can be obtained using these films. Attention is given to the refractive indices for scandium oxide films as a function of wavelength, the power output vs current for laser before coating and after coating with Sc2O3.

  4. Switched-capacitor isolated LED driver

    DOEpatents

    Sanders, Seth R.; Kline, Mitchell

    2016-03-22

    A switched-capacitor voltage converter which is particularly well-suited for receiving a line voltage from which to drive current through a series of light emitting diodes (LEDs). Input voltage is rectified in a multi-level rectifier network having switched capacitors in an ascending-bank configuration for passing voltages in uniform steps between zero volts up to full received voltage V.sub.DC. A regulator section, operating on V.sub.DC, comprises switched-capacitor stages of H-bridge switching and flying capacitors. A current controlled oscillator drives the states of the switched-capacitor stages and changes its frequency to maintain a constant current to the load. Embodiments are described for isolating the load from the mains, utilizing an LC tank circuit or a multi-primary-winding transformer.

  5. Measurement of g Using a Flashing LED

    NASA Astrophysics Data System (ADS)

    Terzella, T.; Sundermier, J.; Sinacore, J.; Owen, C.; Takai, H.

    2008-10-01

    In one of the classic free-fall experiments, a small mass is attached to a strip of paper tape and both are allowed to fall through a spark timer, where sparks are generated at regular time intervals. Students analyze marks (dots) left on the tape by the timer, thereby generating distance-versus-time data, which they analyze to extract the acceleration due to gravity g with good results. The apparatus, however, is cumbersome and often frustrating for students. High-tech versions of this experiment are done with an object dropped and followed by a motion sensor connected to a computer. The sensor relies on ultrasonic ranging to record distance and time data, which may then be displayed graphically. Students inspect the graphs to determine the value of g. Although the results are excellent, the emphasis on the computer's ability to collect and analyze data leaves little analysis for the students to perform.2 Furthermore, neither technique gives an intuitive display of what is happening. The motivation for our work was to overcome these issues by developing an innovative method for measuring g. In our version of the experiment, students drop a flashing LED at a known frequency and record its trajectory using long exposure photography with a digital camera. Proper choice of flashing LED timing parameters produces an image that allows for an accurate measurement of g and at the same time helps to explain what happens during free fall. The experiment remains high-tech in the sense that students learn to use updated equipment to record data and to carry out the analysis.

  6. Open LED Illuminator: A Simple and Inexpensive LED Illuminator for Fast Multicolor Particle Tracking in Neurons

    PubMed Central

    Bosse, Jens B.; Tanneti, Nikhila S.; Hogue, Ian B.; Enquist, Lynn W.

    2015-01-01

    Dual-color live cell fluorescence microscopy of fast intracellular trafficking processes, such as axonal transport, requires rapid switching of illumination channels. Typical broad-spectrum sources necessitate the use of mechanical filter switching, which introduces delays between acquisition of different fluorescence channels, impeding the interpretation and quantification of highly dynamic processes. Light Emitting Diodes (LEDs), however, allow modulation of excitation light in microseconds. Here we provide a step-by-step protocol to enable any scientist to build a research-grade LED illuminator for live cell microscopy, even without prior experience with electronics or optics. We quantify and compare components, discuss our design considerations, and demonstrate the performance of our LED illuminator by imaging axonal transport of herpes virus particles with high temporal resolution. PMID:26600461

  7. Commercialization Assistance Program (CAP)

    SciTech Connect

    Jenny C. Servo, Ph.D.

    2004-07-12

    In order to fulfill the objective of Small Business Innovation Research Program (SBIR), the Department of Energy funds an initiative referred to as the Commercialization Assistance Program (CAP). The over-arching purpose of the CAP is to facilitate transition of the SBIR-funded technology to Phase III defined as private sector investment or receipt of non-sbir dollars to further the commercialization of the technology. Phase III also includes increased sales. This report summarizes the stages involved in the implementation of the Commercialization Assistance Program, a program which has been most successful in fulfilling its objectives.

  8. Commercial Biomedical Experiments Payload

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Experiments to seek solutions for a range of biomedical issues are at the heart of several investigations that will be hosted by the Commercial Instrumentation Technology Associates (ITA), Inc. The biomedical experiments CIBX-2 payload is unique, encompassing more than 20 separate experiments including cancer research, commercial experiments, and student hands-on experiments from 10 schools as part of ITA's ongoing University Among the stars program. Here, Astronaut Story Musgrave activates the CMIX-5 (Commercial MDA ITA experiment) payload in the Space Shuttle mid deck during the STS-80 mission in 1996 which is similar to CIBX-2. The experiments are sponsored by NASA's Space Product Development Program (SPD).

  9. Effects of color temperatures (Kelvin) of LED bulbs on growth performance, carcass characteristics, and ocular welfare indices of broilers grown to heavy weights

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Limited data are available for comparing light-emitting diode (LED) bulbs that are currently available in commercial broiler production facilities. We evaluated the effects of color temperatures (Kelvin) of LED bulbs on growth performance, carcass characteristics, and ocular welfare indices of broil...

  10. 76 FR 70113 - Executive-Led Medical Trade Mission to India Mumbai, New Delhi and Hyderabad March 2-8, 2012

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-10

    ... manner, including publication in the Federal Register ( http://www.gpoaccess.gov/fr ), posting on ITA's... International Trade Administration Executive-Led Medical Trade Mission to India Mumbai, New Delhi and Hyderabad... Commercial Service (CS) is organizing an Executive-Led Medical Trade Mission to India from March 2-8,...

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

    SciTech Connect

    David, Aurelien

    2012-10-15

    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

  12. Warm white LED light by frequency down-conversion of mixed yellow and red Lumogen

    NASA Astrophysics Data System (ADS)

    Mosca, Mauro; Caruso, Fulvio; Zambito, Leandro; Seminara, Biagio; Macaluso, Roberto; Calı, Claudio; Feltin, Eric

    2013-05-01

    This work reports on the benefits and promising opportunities offered by white LED hybrid technology, based on a mixing perylene-based dyes in order to obtain a warm white light for frequency-down conversion. In a standard Ce:YAG-based white LED, the white light appears cold due to the weakness of red wavelength components in the emission spectrum. In order to obtain a warmer white, one possible solution is to add a red phosphor to the yellow one to move the chromatic coordinates properly, though the luminous efficiency drastically decreases due to the increased light absorption of the coating layer. It is generally believed that the low efficiency of warm white LEDs is the main issue today for LED-based lighting. Using photoluminescence of Lumogen® F Yellow 083, a perylene-based polymer dye commercialized by BASF, and adding a small quantity of another perylene-based dye, Lumogen® F Red 305 (BASF), we obtained high-efficiency warm white LEDs by yellow and red conversion from a standard 450 nm GaN/InGaN royal blue LED. Different weight proportions of dyes were dissolved in solutions with equal amounts of poly-methyl-methacrylate (PMMA) in ethyl acetate, then the LEDs were dip-coated in each solution and optically characterized. Record values of 8.03 lm of luminous flux and 116.11 lm/W of optical efficiency were achieved. Finally, the effects of both driving current, and pump wavelength on LED performances - such as chromatic coordinates, correlated color temperature, color rendering index (CRI), and optical efficiency - were investigated.

  13. NASA commercial programs

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Highlights of NASA-sponsored and assisted commercial space activities of 1989 are presented. Industrial R and D in space, centers for the commercial development of space, and new cooperative agreements are addressed in the U.S. private sector in space section. In the building U.S. competitiveness through technology section, the following topics are presented: (1) technology utilization as a national priority; (2) an exploration of benefits; and (3) honoring Apollo-Era spinoffs. International and domestic R and D trends, and the space sector are discussed in the section on selected economic indicators. Other subjects included in this report are: (1) small business innovation; (2) budget highlights and trends; (3) commercial programs management; and (4) the commercial programs advisory committee.

  14. Commercial space launches

    NASA Astrophysics Data System (ADS)

    Robb, David W.

    1984-04-01

    While the space shuttle is expected to be the principle Space Transportation System (STS) of the United States, the Reagan Administration is moving ahead with the President's declared space policy of encouraging private sector operation of expendable launch vehicles (ELV's). With the signing of the “Commercial Space Launch Law” on October 30, the administration hopes that it has opened up the door for commercial ventures into space by streamlining regulations and coordinating applications for launches. The administration considers the development and operation of private sector ELV's as an important part of an overall U.S. space policy, complementing the space shuttle and government ELV's. The law follows by nearly a year the creation of the Office of Commercial Space Transportation at the U.S. Department of Transportation (DOT), which will coordinate applications for commercial space launches.

  15. Commodification and commercial surrogacy.

    PubMed

    Arneson, Richard J

    1992-01-01

    ... In this article I shall argue tentatively for the claim that commercial surrogacy should be legally permissible. I am more strongly convinced that a commitment to feminism should not predispose anyone against surrogacy. At least, no arguments offered so far should persuade anyone who is committed to equal rights for women and men and the dismantling of gender-based hierarchies to favor either legal prohibition or moral condemnation of commercial surrogacy. PMID:11651242

  16. Technology Commercialization Program 1991

    SciTech Connect

    Not Available

    1991-11-01

    This reference compilation describes the Technology Commercialization Program of the Department of Energy, Defense Programs. The compilation consists of two sections. Section 1, Plans and Procedures, describes the plans and procedures of the Defense Programs Technology Commercialization Program. The second section, Legislation and Policy, identifies legislation and policy related to the Program. The procedures for implementing statutory and regulatory requirements are evolving with time. This document will be periodically updated to reflect changes and new material.

  17. Demonstration Assessment of Light-Emitting Diode (LED) Parking Lot Lighting in Leavenworth, KS

    SciTech Connect

    Myer, Michael; Kinzey, Bruce R.; Curry, Ku'uipo

    2011-05-06

    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

  18. Factors that led to the Walkerton tragedy.

    PubMed

    Salvadori, Marina I; Sontrop, Jessica M; Garg, Amit X; Moist, Louise M; Suri, Rita S; Clark, William F

    2009-02-01

    In May 2000, bacterial contamination of municipal water in Walkerton, Ontario, resulted in the worst public health disaster involving municipal water in Canadian history. At least seven people died and 2300 became ill. A public inquiry led by judge Dennis O'Connor examined the events and delineated the causes of the outbreak, including physical causes, the role of the public utilities operators, the public utilities commissioners, the Ministry of the Environment (MOE), and the provincial government. Improper practices and systemic fraudulence by the public utility operators, the recent privatization of municipal water testing, the absence of criteria governing quality of testing, and the lack of provisions made for notification of results to multiple authorities all contributed to the crisis. The MOE noted significant concerns 2 years before the outbreak; however, no changes resulted because voluntary guidelines as opposed to legally binding regulations governed water safety. The inquiry concluded that budgetary restrictions introduced by the provincial government 4 years before the outbreak were enacted with no assessment of risk to human health. The ministers and the cabinet had received warnings about serious risks. Budgetary cuts destroyed the checks and balances that were necessary to ensure municipal water safety. PMID:19180129

  19. Led Astray by Hemoglobin A1c

    PubMed Central

    Chen, Jean; Diesburg-Stanwood, Amy; Bodor, Geza; Rasouli, Neda

    2016-01-01

    Hemoglobin A1c (A1c) is used frequently to diagnose and treat diabetes mellitus. Therefore, it is important be aware of factors that may interfere with the accuracy of A1c measurements. This is a case of a rare hemoglobin variant that falsely elevated a nondiabetic patient’s A1c level and led to a misdiagnosis of diabetes. A 67-year-old male presented to endocrine clinic for further management after he was diagnosed with diabetes based on an elevated A1c of 10.7%, which is approximately equivalent to an average blood glucose of 260 mg/dL. Multiple repeat A1c levels remained >10%, but his home fasting and random glucose monitoring ranged from 92 to 130 mg/dL. Hemoglobin electrophoresis and subsequent genetic analysis diagnosed the patient with hemoglobin Wayne, a rare hemoglobin variant. This variant falsely elevates A1c levels when A1c is measured using cation-exchange high-performance liquid chromatography. When the boronate affinity method was applied instead, the patient’s A1c level was actually 4.7%. Though hemoglobin Wayne is clinically silent, this patient was erroneously diagnosed with diabetes and started on an antiglycemic medication. Due to this misdiagnosis, the patient was at risk of escalation in his “diabetes management” and hypoglycemia. Therefore, it is important that providers are aware of factors that may result in hemoglobin A1c inaccuracy including hemoglobin variants. PMID:26848480

  20. Novel aplanatic designs for LED concentration

    NASA Astrophysics Data System (ADS)

    Ricketts, Melissa; Winston, Roland; Jiang, Lun

    2014-09-01

    Aplanats make great concentrators because of their near perfect imaging. Aplanatic conditions can be satisfied using two surface curves (generally mirrored surfaces) in two dimensions (see Figure 1) which are constructed by successive approximation to create a highly efficient concentrator for both concentration and illumination. For concentration purposes, having a two mirror system would be impossible because the front mirror would block incoming light (see figure 2) so the idea is to replace the front mirror with a "one-way" mirror. Light from a lower index can be transmitted, so if the aplanat surface is a higher index light is allowed to enter, and be trapped. In the Jellyfish design, TIR takes place except for light striking the surface within the range of critical angles. To combat that, a small area of reflective coating is applied to the central top part of the Jellyfish, where TIR fails (In the middle) to keep the light there from directly escaping (see figure 3). The design works in both forwards and reverse. Light entering can be focused to a collecter, or the collecter can be replaced with a light source to concentrate light out. In this case, LEDs are used for their highly efficienct properties.

  1. Blue LED irradiation to hydration of skin

    NASA Astrophysics Data System (ADS)

    Menezes, Priscila F. C.; Requena, Michelle B.; Lizarelli, Rosane F., Z.; Bagnato, Vanderlei S.

    2015-06-01

    Blue LED system irradiation shows many important properties on skin as: bacterial decontamination, degradation of endogenous skin chromophores and biostimulation. In this clinical study we prove that the blue light improves the skin hydration. In the literature none authors reports this biological property on skin. Then this study aims to discuss the role of blue light in the skin hydration. Twenty patients were selected to this study with age between 25-35 years old and phototype I, II and III. A defined area from forearm was pre determined (A = 4.0 cm2). The study was randomized in two treatment groups using one blue light device (power of 5.3mW and irradiance of 10.8mW/cm2). The first treatment group was irradiated with 3J/cm2 (277seconds) and the second with 6J/cm2 (555 seconds). The skin hydration evaluations were done using a corneometer. The measurements were collected in 7, 14, 21 and 30 days, during the treatment. Statistical test of ANOVA, Tukey and T-Student were applied considering 5% of significance. In conclusion, both doses were able to improve the skin hydration; however, 6J/cm2 has kept this hydration for 30 days.

  2. LED-based digital diameter measurement

    NASA Astrophysics Data System (ADS)

    Kleuver, Wolfram; Becker, Lothar

    1995-01-01

    This paper presents a new industrial sensor for measuring diameters of extreme thin objects. The system is divided in two parts. The first is the emitter and the second the receiver. It is possible to use this system for the automatic inspection of files and wires in the textile industries and wire works. Another application for the sensor is the control of production of chemical files in an extruder. Furthermore we can measure more than one object in the lightbeam because we get information not only about the dimensions also about the position of the objects in the beam. The innovation in this system is the using of a light emitting diode (LED) as emitter and the realization of a long distance of about two or more meters between the two sensorheads. The results of this development are a special kind of optical layout in the emitter to reduce the loss of intensity and minimize the divergence of the lightbeam. It is not necessary to develop an intensity distribution, which is equal over the complete width of the sensorhead. We can show that we have a better dynamic in the system with this feature. The experiments prove that we get the same resolution as a laserbeamsensor. Furthermore one advantage is the eye-safety.

  3. ERC commercialization activities

    SciTech Connect

    1995-08-01

    The ERC family of companies is anticipating market entry of their first commercial product, a 2.8-MW power plant, in the second quarter of 1999. The present Cooperative Agreement provides for: (1) Commercialization planning and organizational development, (2) Completion of the pre-commercial DFC technology development, (3) Systems and plant design, (4) Manufacturing processes` scale-up to full-sized stack components and assemblies, (5) Upgrades to ERC`s test facility for full-sized stack testing, (6) Sub-scale testing of a DFC Stack and BOP fueled with landfill gas. This paper discusses the first item, that of preparing for commercialization. ERC`s formal commercialization program began in 1990 with the selection of the 2-MW Direct Fuel Cell power plant by the American Public Power Association (APPA) for promotion to the over 2000 municipal utilities comprising APPA`s segment of the utility sector. Since that beginning, the APPA core group expanded to become the Fuel Cell Commercialization Group (FCCG) which includes representation from all markets - utilities and other power generation equipment buyers.

  4. ERC commercialization activities

    SciTech Connect

    Maru, H.C.

    1995-12-01

    The ERC family of companies is anticipating market entry of their first commercial product, a 2.8-MR power plant, in the second quarter of 1999. The present Cooperative Agreement provides for: (1) Commercialization planning and organizational development, (2) Completion of the pre-commercial DFC technology development, (3) Systems and plant design, (4) Manufacturing processes` scale-up to full- sized stack components and assemblies, (5) Upgrades to ERC`s test facility for full-sized stack testing, and (6) Sub-scale testing of a DFC Stack and BOP fueled with landfill gas. This paper discusses the first item, that of preparing for commercialization. ERC`s formal commercialization program began in 1990 with the selection of the 2-MR Direct Fuel Cell power plant by the American Public Power Association (APPA) for promotion to the over 2000 municipal utilities comprising APPA`s segment of the utility sector. Since that beginning, the APPA core group expanded to become the Fuel Cell Commercialization Group (FCCG) which includes representation from all markets - utilities and other power generation equipment buyers.

  5. Image-like illumination with LED arrays: design.

    PubMed

    Moreno, Ivan

    2012-03-01

    An array of spatially distributed light-emitting diodes (LEDs) can produce an illumination pattern that approaches an image by individually modulating each LED. In this letter, I analyze the first-order design of such systems in order to achieve the best match between the illumination distribution and a desired image. In particular, simple formulas are given for the optimal number of LEDs, working distance, array size, and LED beam pattern. The analysis developed here may be applied to the design of LED systems such as architecture lighting, energy-efficient lighting, backlight local dimming for displays, and structured illumination microscopy with micro-LED arrays. PMID:22378411

  6. Application of LEDs to Fishing Lights for Pacific Saury

    NASA Astrophysics Data System (ADS)

    Okamoto, Tamotsu; Takahashi, Kunio; Ohsawa, Hiroshi; Fukuchi, Ken-Ichi; Hosogane, Koichi; Kobayashi, Satoshi; Moniwa, Masahiro; Sasa, Kimio; Yoshino, Hirotaka; Ishikawa, Hiroyoshi; Harada, Makoto; Asakura, Kenji; Ishii, Hiromitsu

    We attempted the development of highly efficient fishing lights using LEDs for saury fishing. Considering the spectral luminous efficacy characteristic of a Pacific saury, LED fishing lights were fabricated. Transmission properties in sea water in LED fishing lights were investigated, and it was found that the fabricated LED fishing lights sufficiently can be utilized even in sea water. Furthermore, we attempted the saury-fishing experiments by using the LED fishing lights, and comparable catch of Pacific saury was achieved by approximately 55% electric power by using both LED poles and incandescent lamp poles.

  7. Color Appearance under LED Illumination: The Visual Judgment of Observers

    NASA Astrophysics Data System (ADS)

    Viénot, Françoise; Mahler, Elodie; Ezrati, Jean-Jacques; Boust, Clotilde; Rambaud, Ablane; Bricoune, Alain

    The advantages of LED lighting are discussed. We report experiments where observers graded the quality of several light-emitting diode (LED) illuminations. One experiment is based on color discrimination and two experiments are based on the judgement of appearance. We conclude that clusters with red, green, blue, and/or amber LEDs impair color discrimination, although they seem to locally enhance the color gamut. We also conclude that LED clusters that include white LEDs and a few correcting color LED may render colors faithfully.

  8. Validating Community-Led Forest Biomass Assessments.

    PubMed

    Venter, Michelle; Venter, Oscar; Edwards, Will; Bird, Michael I

    2015-01-01

    The lack of capacity to monitor forest carbon stocks in developing countries is undermining global efforts to reduce carbon emissions. Involving local people in monitoring forest carbon stocks could potentially address this capacity gap. This study conducts a complete expert remeasurement of community-led biomass inventories in remote tropical forests of Papua New Guinea. By fully remeasuring and isolating the effects of 4,481 field measurements, we demonstrate that programmes employing local people (non-experts) can produce forest monitoring data as reliable as those produced by scientists (experts). Overall, non-experts reported lower biomass estimates by an average of 9.1%, equivalent to 55.2 fewer tonnes of biomass ha(-1), which could have important financial implications for communities. However, there were no significant differences between forest biomass estimates of expert and non-expert, nor were there significant differences in some of the components used to calculate these estimates, such as tree diameter at breast height (DBH), tree counts and plot surface area, but were significant differences between tree heights. At the landscape level, the greatest biomass discrepancies resulted from height measurements (41%) and, unexpectedly, a few large missing trees contributing to a third of the overall discrepancies. We show that 85% of the biomass discrepancies at the tree level were caused by measurement taken on large trees (DBH ≥50 cm), even though they consisted of only 14% of the stems. We demonstrate that programmes that engage local people can provide high-quality forest carbon data that could help overcome barriers to reducing forest carbon emissions in developing countries. Nonetheless, community-based monitoring programmes should prioritise reducing errors in the field that lead to the most important discrepancies, notably; overcoming challenges to accurately measure large trees. PMID:26126186

  9. Validating Community-Led Forest Biomass Assessments

    PubMed Central

    Venter, Michelle; Venter, Oscar; Edwards, Will; Bird, Michael I.

    2015-01-01

    The lack of capacity to monitor forest carbon stocks in developing countries is undermining global efforts to reduce carbon emissions. Involving local people in monitoring forest carbon stocks could potentially address this capacity gap. This study conducts a complete expert remeasurement of community-led biomass inventories in remote tropical forests of Papua New Guinea. By fully remeasuring and isolating the effects of 4,481 field measurements, we demonstrate that programmes employing local people (non-experts) can produce forest monitoring data as reliable as those produced by scientists (experts). Overall, non-experts reported lower biomass estimates by an average of 9.1%, equivalent to 55.2 fewer tonnes of biomass ha-1, which could have important financial implications for communities. However, there were no significant differences between forest biomass estimates of expert and non-expert, nor were there significant differences in some of the components used to calculate these estimates, such as tree diameter at breast height (DBH), tree counts and plot surface area, but were significant differences between tree heights. At the landscape level, the greatest biomass discrepancies resulted from height measurements (41%) and, unexpectedly, a few large missing trees contributing to a third of the overall discrepancies. We show that 85% of the biomass discrepancies at the tree level were caused by measurement taken on large trees (DBH ≥50cm), even though they consisted of only 14% of the stems. We demonstrate that programmes that engage local people can provide high-quality forest carbon data that could help overcome barriers to reducing forest carbon emissions in developing countries. Nonetheless, community-based monitoring programmes should prioritise reducing errors in the field that lead to the most important discrepancies, notably; overcoming challenges to accurately measure large trees. PMID:26126186

  10. Key inventions in the history of nitride-based blue LED and LD

    NASA Astrophysics Data System (ADS)

    Akasaki, Isamu

    2007-03-01

    It was quite difficult to grow high quality single crystals of nitrides and impossible to control their electric conduction. These problems prevented the development of nitride-based devices for many years. In 1986, a dramatic improvement in the crystalline quality of GaN was achieved by use of low-temperature-deposited (LT) buffer layer technology in metalorganic vapor phase epitaxy. In 1989, the high quality GaN enabled us to produce p-type conduction in nitrides and to control the conductivity of n-type nitrides. These achievements led to the invention of the world's first GaN p-n junction blue/UV LED in 1989. Room temperature UV stimulated emission, which is indispensable for laser operation, was also achieved in 1990 by use of high quality GaN films grown with the LT-buffer layers. These breakthroughs inspired nitride researchers around the world to greater efforts, and eventually led to the commercialization of high-performance blue LEDs and long-life violet LDs as well as the development of nitride-based devices such as high-speed transistors. Furthermore, unique properties such as a large piezoelectric effect were also clarified due to the marked improvements in crystal quality of nitrides. In this paper, key inventions during the development of nitride-based blue LED and LD are reviewed and a recent advance in UV devices is also described.

  11. Phosphor in glass with Eu3+ and Pr3+-doped silicate glasses for LED color conversion

    NASA Astrophysics Data System (ADS)

    Park, Hyun-A.; Lee, Yl Kwon; Im, Won Bin; Heo, Jong; Chung, Woon Jin

    2015-03-01

    Phosphor-in-glasses (PiGs) with rare earth (RE) doped SiO2-B2O3-RO glasses were prepared by embedding YAG:Ce3+ as the yellow phosphor. Eu3+ and Pr3+ were used to dope the glass, varying their concentrations in order to provide red emissions for possible chromaticity-control of white-light emitting diodes (WLEDs). The glass-to-phosphor mixing ratio was also varied to find the proper combination for color-controlled white LEDs. PiGs with RE-doped glasses were sintered at 750 °C and polished to 250 μm in thickness for blue LED color conversion. The photoluminescence spectra of the PiGs were monitored after they were mounted on commercial blue LED chips. Variation of color coordination, color rendering index and correlated color temperature were observed due to red emissions from the doped RE-ions. The spectral contribution of Eu3+ and Pr3+ ions to white LEDs under 450 nm LED excitation was discussed. The spatial distribution of phosphors within the glass matrix, and their possible interaction, was inspected by SEM. The thermal quenching effect was also investigated.

  12. Improved wound healing in blue LED treated superficial abrasions

    NASA Astrophysics Data System (ADS)

    Rossi, Francesca; Tatini, Francesca; Pini, Roberto; Bacci, Stefano; De Siena, Gaetano; Cicchi, Riccardo; Pavone, Francesco; Alfieri, Domenico

    2013-06-01

    A blue-LED photocoagulator device was designed in order to induce a selective photocoagulation effect in superficial bleeding. An in vivo study in rat back skin evidenced an improved healing process in the LED treated abrasions.

  13. Commercialization of NESSUS: Status

    NASA Technical Reports Server (NTRS)

    Thacker, Ben H.; Millwater, Harry R.

    1991-01-01

    A plan was initiated in 1988 to commercialize the Numerical Evaluation of Stochastic Structures Under Stress (NESSUS) probabilistic structural analysis software. The goal of the on-going commercialization effort is to begin the transfer of Probabilistic Structural Analysis Method (PSAM) developed technology into industry and to develop additional funding resources in the general area of structural reliability. The commercialization effort is summarized. The SwRI NESSUS Software System is a general purpose probabilistic finite element computer program using state of the art methods for predicting stochastic structural response due to random loads, material properties, part geometry, and boundary conditions. NESSUS can be used to assess structural reliability, to compute probability of failure, to rank the input random variables by importance, and to provide a more cost effective design than traditional methods. The goal is to develop a general probabilistic structural analysis methodology to assist in the certification of critical components in the next generation Space Shuttle Main Engine.

  14. Mapping Student-Led Peer Learning in the UK

    ERIC Educational Resources Information Center

    Keenan, Chris

    2014-01-01

    Peer-led academic learning has increased in importance, but there is little sense of how many institutions support it, how they understand its purposes or what peer-led learning best practice is. This report examines the provision of peer-led learning in the UK. It identifies challenges and opportunities, including international perspectives and…

  15. Photorealistic rendering application to the design of LED flash lens

    NASA Astrophysics Data System (ADS)

    Chern, Jyh-Long

    2012-10-01

    LED flash module becomes popular in current mobile communication devices, such as for the smart phones and tablet. As a lighting apparatus for image taking, photo rendering performance is crucial. We explore the LED flash lens design with a stress of photorealistic rendering application toward a high-performance LED flash illumination.

  16. High Efficiency Driving Electronics for General Illumination LED Luminaires

    SciTech Connect

    Upadhyay, Anand

    2012-10-31

    New generation of standalone LED driver platforms developed, which are more efficient These LED Drivers are more efficient (≥90%), smaller in size ( 0.15 in3/watt), lower in cost ( 12 cents/watt in high volumes in millions of units). And these products are very reliable having an operating life of over 50,000 hours. This technology will enable growth of LED light sources in the use. This will also help in energy saving and reducing total life cycle cost of LED units. Two topologies selected for next generation of LED drivers: 1) Value engineered single stage Flyback topology. This is suitable for low powered LED drivers up to 50W power. 2) Two stage boost power factor correction (PFC) plus LLC half bridge platform for higher powers. This topology is suitable for 40W to 300W LED drivers. Three new product platforms were developed to cover a wide range of LED drivers: 1) 120V 40W LED driver, 2) Intellivolt 75W LED driver, & 3) Intellivolt 150W LED driver. These are standalone LED drivers for rugged outdoor lighting applications. Based on these platforms number of products are developed and successfully introduced in the market place meeting key performance, size and cost goals.

  17. Computer-Based Experiment for Determining Planck's Constant Using LEDs

    ERIC Educational Resources Information Center

    Zhou, Feng; Cloninger, Todd

    2008-01-01

    Visible light emitting diodes (LEDs) have been widely used as power indicators. However, after the power is switched off, it takes a while for the LED to go off. Many students were fascinated by this simple demonstration. In this paper, by making use of computer-based data acquisition and modeling, we show the voltage across the LED undergoing an…

  18. LEDs: DOE Programs Add Credibility to a Developing Technology

    ERIC Educational Resources Information Center

    Conbere, Susan

    2009-01-01

    LED (light-emitting diode) technology is moving fast, and with justification, some facility managers have viewed it with a wary eye. Some LEDs on the market do not perform as promised, and the technology is changing rapidly. But new developments from the U.S. Department of Energy (DOE) now make it easier for facility managers to find LEDs that…

  19. Evaluating method for the double image phenomenon of LED lighting

    NASA Astrophysics Data System (ADS)

    Wu, Wen-Hong; Kuo, Chao-Hui; Hung, Min-Wei; Huang, Kuo-Cheng

    In recent years, the overriding advantages long life, high efficiency, small size and short reaction time have made LED become a viable alternative to conventional light sources. LED lighting sources are usually composed of several individual LED cells which must be mounted on a panel as a lighting module. Being composed of several individual LED cells, the LED sources will cause the double image phenomenon. The double image phenomenon is more obvious when the LED sources are more closer, such as LED table lamp, and limits the applications of LED sources. By using a proper secondary optical lens, the double image phenomenon can be reduced. In this research, an evaluating method based on image processing is developed for the double image phenomenon of a LED sources. By analyzing the gray-scale of the grabbed image which is obtained by putting a rob under a LED source, an index of double image can be established and be a criterion to judge different LED sources. Furthermore, a series of LED lighting simulations are shown in this paper and several type of secondary optical lens are compared and discussed in this paper as well.

  20. CALiPER Snapshot Report: Indoor LED Luminaires

    SciTech Connect

    2014-04-01

    Snapshot reports use data from DOE's LED Lighting Facts product list to compare the LED performance to standard technologies, and are designed to help lighting retailers, distributors, designers, utilities, energy efficiency program sponsors, and other stakeholders understand the current state of the LED market and its trajectory.

  1. Teaching CAD at the University: Specifically Written or Commercial Software?

    ERIC Educational Resources Information Center

    Garcia, Ramon Rubio; Quiros, Javier Suarez; Santos, Ramon Gallego; Penin, Pedro I. Alvarez

    2007-01-01

    At most universities throughout the world Computer Aided Design is taught using commercial programs more suitable for business and industry than for teaching. This led us to write our own design program (GIcad) starting from the best-known standards on the market, but always avoiding unnecessary commands in the first steps of the learning process.…

  2. Giving Kids the Business: The Commercialization of America's Schools.

    ERIC Educational Resources Information Center

    Molnar, Alex

    Corporate involvement in public education is nothing new. This book offers a critique of the growing corporate control and commercialization of public schools. Chapter 1 describes the history of business influence on American education with a focus on the case of Wisconsin, in which the corporate-led restructuring of the American economy has…

  3. Design and construction evaluation of a photovoltaic DC LED lighting system

    NASA Astrophysics Data System (ADS)

    Bhamidipati, Jyotsna

    2008-08-01

    The market demand for commercialization of Photovoltaic (PV) systems depends a lot on the reliability, efficiency and performance of various components within the system. PV panels produce DC power when exposed to sunlight, and an inverter converts this to AC power in a typical solar powered building. Though, PV lighting has existed for a long time it hasn't been very effective, as incandescent light sources were commonly used which are inefficient. Today fluorescent fixtures are mostly used with PV's due to its high efficacy. Light-emitting diodes present a new vision to energy efficiency in lighting design with their low energy consumption. Current research predicts improved efficiencies of LED light fixtures and their commercial use is a few years away. LEDs which operate on DC voltages when coupled with photovoltaics can be a simple PV lighting application and a sustainable solution with potential for payback. This research evaluates the design and construction of a photovoltaic DC LED lighting system for a solar house at Pennsylvania State University. A detailed cost and payback analysis of a PV DC LED lighting system is presented in this research. PV output simulations for the solar house are presented. Results presented in this research indicate that the Solid state lighting market is evolving rapidly and that LED's are a choice in stand-alone photovoltaic DC lighting systems. The efficiency and the cost-effectiveness of such systems would however improve in the coming years with research and development now focused on PV systems and on Solid state lighting technologies.

  4. Site-specific standard request for underground storage tanks 1219-U, 1222-U, 2082-U, and 2068-U at the rust garage facility buildings 9754-1 and 9720-15: Oak Ridge Y-12 Plant, Oak Ridge, Tennessee, Facility ID No. 0-010117

    SciTech Connect

    1994-12-01

    This document represents a Site-specific Standard Request for underground storage tanks (USTs) 1219-U,1222-U and 2082-U previously located at former Building 9754-1, and tank 2086-U previously located at Building 9720-15, Oak Ridge Y-12 Plant, Oak Ridge, Tennessee. The tanks previously contained petroleum products. For the purposes of this report, the two building sites will be regarded as a single UST site and will be referred to as the Rust Garage Facility. The current land use associated with the Y-12 Plant is light industrial and the operational period of the plant is projected to be at least 30 years. Thus, potential future residential exposures are not expected to occur for at least 30 years. Based on the degradation coefficient for benzene (the only carcinogenic petroleum constituent detected in soils or groundwater at the Rust Garage Facility), it is expected that the benzene and other contaminants at the site will likely be reduced prior to expiration of the 30-year plant operational period. As the original sources of petroleum contamination have been removed, and the area of petroleum contamination is limited, a site-specific standard is therefore being requested for the Rust Garage Facility.

  5. Commercialization of biobanks.

    PubMed

    Evers, Kathinka; Forsberg, Joanna; Hansson, Mats

    2012-02-01

    Biobank policy and regulations profoundly vary between different societies. One area with profound differences in culture and tradition concerns commercialization, and the possibility of using the human body as a capital resource. In the United States there is acceptance of this possibility, whereas European law is based on principles that categorically prohibit selling parts of the human body. We suggest that questions of commercialization in the area of biobanking must be considered in relation to different ethical values, notably the principle of best possible use of collected biobank materials for the benefit of vital patient interests. PMID:24849753

  6. Commercial Biomedical Experiments

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Experiments to seek solutions for a range of biomedical issues are at the heart of several investigations that will be hosted by the Commercial Instrumentation Technology Associates (ITA), Inc. Biomedical Experiments (CIBX-2) payload. CIBX-2 is unique, encompassing more than 20 separate experiments including cancer research, commercial experiments, and student hands-on experiments from 10 schools as part of ITA's ongoing University Among the Stars program. Valerie Cassanto of ITA checks the Canadian Protein Crystallization Experiment (CAPE) carried by STS-86 to Mir in 1997. The experiments are sponsored by NASA's Space Product Development Program (SPD).

  7. Commercial Fisheries Surveys

    USGS Publications Warehouse

    Fabrizio, Mary C.; Richards, R. Anne

    1996-01-01

    In this chapter, we describe methods for sampling commercial fisheries and identify factors affecting the design of sampling plans. When sampled properly, commercial fisheries can provide important information on the response of aquatic organisms to exploitation; such information can be used by management agencies to develop regulations for ensuring long-term production of the resource and long-term economic benefit. Fishery statistics are typically used to estimate abundance, mortality, recruitment, growth, and other vital characterisitcs of populations. Fishery statistics can also be used to study changes in fish community composition resulting from differential exploitation of species.

  8. High power LEDs and the organization of light

    NASA Astrophysics Data System (ADS)

    Paolini, Steve; Harbers, Gerard

    2006-02-01

    High-power Light Emitting Diodes (LEDs) were introduced in the market in 1998 by Lumileds. High-power LEDs have unique properties, very different from conventional light sources, creating never before possible solutions available to lighting designers. In this paper we will give an update on these devices and discuss the main benefits of LEDs compared to more traditional light sources. We will show that the benefits of high-power LEDs also relate to the organization of light they emit. Comparisons of more and less organized light sources as well as applications for highpower LEDs will be discussed.

  9. Smart power supply system for LED street lighting

    NASA Astrophysics Data System (ADS)

    Risteiu, Mircea; Ileana, Ioan; Marc, Gheorghe; Sofalca, Ionut

    2015-02-01

    The paper is focused on designing a smart LED power supply, with adjustable working point in accordance with local conditions, LED photometric characteristics. We have develop a flyback driver controlled by a signal which is a combination of the sensed LED forward current, and a PWM working regime. This method is used in order to increase the LED lighting efficiency at the same thermal regime. At the end of the implementation we have tested major issues related to the correct work of the LED, energetic and luminous efficiency, and the way of sensor integration into the smart system.

  10. Advanced packaging methods for high-power LED modules

    NASA Astrophysics Data System (ADS)

    Jordan, Rafael C.; Weber, Constanze; Ehrhardt, Christian; Wilke, Martin

    2014-02-01

    LED luminaires are already beyond retrofit systems, which are limited in heat dissipation due to the old fitting standards. Actual LED luminaries are based on new LED packages and modules. Heat dissipation through the first and second level interconnect is a key issue for a successful LED package. Therefore the impact of known bonding technologies as gluing and soldering and new technologies like sintering and transient liquid phase soldering were analyzed and compared. A realized hermetic high power LED package will be shown as example. The used new techniques result in a module extremely stable against further assembly processes and harsh operating conditions.

  11. Hyperspectral fluorescence imaging with multi wavelength LED excitation

    NASA Astrophysics Data System (ADS)

    Luthman, A. Siri; Dumitru, Sebastian; Quirós-Gonzalez, Isabel; Bohndiek, Sarah E.

    2016-04-01

    Hyperspectral imaging (HSI) can combine morphological and molecular information, yielding potential for real-time and high throughput multiplexed fluorescent contrast agent imaging. Multiplexed readout from targets, such as cell surface receptors overexpressed in cancer cells, could improve both sensitivity and specificity of tumor identification. There remains, however, a need for compact and cost effective implementations of the technology. We have implemented a low-cost wide-field multiplexed fluorescence imaging system, which combines LED excitation at 590, 655 and 740 nm with a compact commercial solid state HSI system operating in the range 600 - 1000 nm. A key challenge for using reflectance-based HSI is the separation of contrast agent fluorescence from the reflectance of the excitation light. Here, we illustrate how it is possible to address this challenge in software, using two offline reflectance removal methods, prior to least-squares spectral unmixing. We made a quantitative comparison of the methods using data acquired from dilutions of contrast agents prepared in well-plates. We then established the capability of our HSI system for non-invasive in vivo fluorescence imaging in small animals using the optimal reflectance removal method. The HSI presented here enables quantitative unmixing of at least four fluorescent contrast agents (Alexa Fluor 610, 647, 700 and 750) simultaneously in living mice. A successful unmixing of the four fluorescent contrast agents was possible both using the pure contrast agents and with mixtures. The system could in principle also be applied to imaging of ex vivo tissue or intraoperative imaging in a clinical setting. These data suggest a promising approach for developing clinical applications of HSI based on multiplexed fluorescence contrast agent imaging.

  12. Commercial Baking. Final Report.

    ERIC Educational Resources Information Center

    Booth, Nancy

    A project filmed three commercial baking videotapes for use by secondary and adult students in food service programs. The three topics were basic dinner rolls, bread making, and hard breads and rolls. Quick-rise dough recipes were developed, written down, and explained for use with the videotapes. A pretest, posttest, and student guide were…

  13. Commercialization of the Internet.

    ERIC Educational Resources Information Center

    Weis, Allan H.

    1992-01-01

    Traces the growth of the Internet from its beginnings as the Defense Advanced Research Project Agency's ARPAnet. Discusses key issues facing network service providers including: acceptable use policies, liability exposure, the integration of research and production networks, the commercialization of the networks, and the need for global planning.…

  14. Commercial applications of telemedicine

    NASA Technical Reports Server (NTRS)

    Natiello, Thomas A.

    1991-01-01

    Telemedicine Systems Corporation was established in 1976 and is a private commercial supplier of telemedicine systems. These systems are various combinations of communications and diagnostic technology, designed to allow the delivery of health care services to remote facilities. The technology and the health care services are paid for by the remote facilities, such as prisons.

  15. Commercial Earth Observation

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Through the Earth Observation Commercial Applications Program (EOCAP) at Stennis Space Center, Applied Analysis, Inc. developed a new tool for analyzing remotely sensed data. The Applied Analysis Spectral Analytical Process (AASAP) detects or classifies objects smaller than a pixel and removes the background. This significantly enhances the discrimination among surface features in imagery. ERDAS, Inc. offers the system as a modular addition to its ERDAS IMAGINE software package for remote sensing applications. EOCAP is a government/industry cooperative program designed to encourage commercial applications of remote sensing. Projects can run three years or more and funding is shared by NASA and the private sector participant. Through the Earth Observation Commercial Applications Program (EOCAP), Ocean and Coastal Environmental Sensing (OCENS) developed SeaStation for marine users. SeaStation is a low-cost, portable, shipboard satellite groundstation integrated with vessel catch and product monitoring software. Linked to the Global Positioning System, SeaStation provides real time relationships between vessel position and data such as sea surface temperature, weather conditions and ice edge location. This allows the user to increase fishing productivity and improve vessel safety. EOCAP is a government/industry cooperative program designed to encourage commercial applications of remote sensing. Projects can run three years or more and funding is shared by NASA and the private sector participant.

  16. Commercial and Industrial Wiring.

    ERIC Educational Resources Information Center

    Kaltwasser, Stan; Flowers, Gary

    This module is the third in a series of three wiring publications, includes additional technical knowledge and applications required for job entry in the commercial and industrial wiring trade. The module contains 15 instructional units that cover the following topics: blueprint reading and load calculations; tools and equipment; service;…

  17. Commercial Crew Medical Ops

    NASA Technical Reports Server (NTRS)

    Heinbaugh, Randall; Cole, Richard

    2016-01-01

    Provide commercial partners with: center insight into NASA spaceflight medical experience center; information relative to both nominal and emergency care of the astronaut crew at landing site center; a basis for developing and sharing expertise in space medical factors associated with returning crew.

  18. Commercializing Biological Control

    ERIC Educational Resources Information Center

    LeLeu, K. L.; Young, M. A.

    1973-01-01

    Describes the only commercial establishment involved in biological control in Australia. The wasp Aphitis melinus, which parasitizes the insect Red Scale, is bred in large numbers and released in the citrus groves where Red Scale is causing damage to the fruit. (JR)

  19. Commercial Carpentry: Instructional Units.

    ERIC Educational Resources Information Center

    Diehl, Donald W.; Penner, Wayman R.

    This manual contains instructional materials which measure student performance on commercial carpentry behavioral objectives; criterion-referenced evaluation instruments are also included. Each of the manual's eleven sections consists of one or more units of instruction. Each instructional unit includes behavioral objectives, suggested activities…

  20. Preparation and Evaluation of a Zirconia/Oligosiloxane Nanocomposite for LED Encapsulation.

    PubMed

    Chung, Pao-Tang; Chiou, Shian-Hau; Tseng, Chin-Yao; Chiang, Anthony Shiaw-Tseh

    2016-04-20

    A zirconia/oligosiloxane nanocomposite encapsulant has been developed and tested in a high-power LED package against commercial silicone resins. The composite was a marriage of zirconia nanocrystals modified with butyric acid (BA) and 3-methacryloxy propyl trimethoxysilane (MPTMS) and a high-index methacryloxy-oligosiloxanes resin made from MPTMS plus dimethyl, diphenyl, and triphenyl silanes. The modified zirconia had an index of 1.762 (@589 nm) and was dispersible in many solvents. The oligosiloxane resin, however, had an index of 1.5413 with good encapsulation properties and low viscosity allowing the incorporation of more zirconia. The final nanocomposite showed a refractive index of 1.625 with high transparency and a wavelength-independent scattering, both desirable for the light extraction from LED. When tested in a high-power LED package, the composite encapsulant resulted in 13% more light output compared to the commercial encapsulant (OE-6630, Dow Corning Corp.) and showed longer than 1000 h of lifetime (L70) under the steady-state Temperature Humidity Bias (THB) test. PMID:27029544

  1. A simple and low-cost biofilm quantification method using LED and CMOS image sensor.

    PubMed

    Kwak, Yeon Hwa; Lee, Junhee; Lee, Junghoon; Kwak, Soo Hwan; Oh, Sangwoo; Paek, Se-Hwan; Ha, Un-Hwan; Seo, Sungkyu

    2014-12-01

    A novel biofilm detection platform, which consists of a cost-effective red, green, and blue light-emitting diode (RGB LED) as a light source and a lens-free CMOS image sensor as a detector, is designed. This system can measure the diffraction patterns of cells from their shadow images, and gather light absorbance information according to the concentration of biofilms through a simple image processing procedure. Compared to a bulky and expensive commercial spectrophotometer, this platform can provide accurate and reproducible biofilm concentration detection and is simple, compact, and inexpensive. Biofilms originating from various bacterial strains, including Pseudomonas aeruginosa (P. aeruginosa), were tested to demonstrate the efficacy of this new biofilm detection approach. The results were compared with the results obtained from a commercial spectrophotometer. To utilize a cost-effective light source (i.e., an LED) for biofilm detection, the illumination conditions were optimized. For accurate and reproducible biofilm detection, a simple, custom-coded image processing algorithm was developed and applied to a five-megapixel CMOS image sensor, which is a cost-effective detector. The concentration of biofilms formed by P. aeruginosa was detected and quantified by varying the indole concentration, and the results were compared with the results obtained from a commercial spectrophotometer. The correlation value of the results from those two systems was 0.981 (N = 9, P < 0.01) and the coefficients of variation (CVs) were approximately threefold lower at the CMOS image-sensor platform. PMID:25455019

  2. Space Station Freedom commercial infrastructure

    NASA Technical Reports Server (NTRS)

    Barquinero, Kevin; Cassidy, Jeff

    1989-01-01

    NASA policy concerning the commercial infrastructure of the Space Station is examined. Plans for receiving and evaluating unsolicited proposals to provide commercial infrastructure are outlined. The guidelines for development of the commercial infrastructure and examples of opportunities for industry are listed. Also, a program for industry feedback concerning the commercial infrastructure policy is discussed.

  3. Straightforward fabrication of stable white LEDs by embedding of inorganic UV-LEDs into bulk polymerized polymethyl-methacrylate doped with organic dyes

    PubMed Central

    Di Martino, Daniela; Beverina, Luca; Sassi, Mauro; Brovelli, Sergio; Tubino, Riccardo; Meinardi, Francesco

    2014-01-01

    Stable white-emitting down-converted LEDs are straightforwardly prepared by bulk polymerization of an organic dye doped polymethyl-methacrylate (PMMA) shell directly on top of a highly efficient commercial blue-emitting InGaN LED. Our optimized polymerization procedure allows for extending the form factor of achievable luminescence converter (LUCO) material beyond the conventional thin film form and to directly produce devices with light bulb design. The selected organic dyes, the blue-emitting Coumarin 30 and a red-emitting diketopyrrolopyrrole derivative, exhibit high compatibility with the free radical polymerization reaction of the PMMA matrix and ensure high stability of the final hybrid device. The control of both the thickness of the PMMA shell and the concentration of the dopant dyes allow for fine tuning of the emission color of the LUCO LED and to obtain white light with CIE chromatic coordinates x = 0.32 and y = 0.33, with rendering index as high as 80. This simple and versatile procedure is not dye-exclusive and is therefore extendable to other molecular systems for color-tunable efficient solid-state lighting sources. PMID:24638041

  4. Straightforward fabrication of stable white LEDs by embedding of inorganic UV-LEDs into bulk polymerized polymethyl-methacrylate doped with organic dyes.

    PubMed

    Di Martino, Daniela; Beverina, Luca; Sassi, Mauro; Brovelli, Sergio; Tubino, Riccardo; Meinardi, Francesco

    2014-01-01

    Stable white-emitting down-converted LEDs are straightforwardly prepared by bulk polymerization of an organic dye doped polymethyl-methacrylate (PMMA) shell directly on top of a highly efficient commercial blue-emitting InGaN LED. Our optimized polymerization procedure allows for extending the form factor of achievable luminescence converter (LUCO) material beyond the conventional thin film form and to directly produce devices with light bulb design. The selected organic dyes, the blue-emitting Coumarin 30 and a red-emitting diketopyrrolopyrrole derivative, exhibit high compatibility with the free radical polymerization reaction of the PMMA matrix and ensure high stability of the final hybrid device. The control of both the thickness of the PMMA shell and the concentration of the dopant dyes allow for fine tuning of the emission color of the LUCO LED and to obtain white light with CIE chromatic coordinates x = 0.32 and y = 0.33, with rendering index as high as 80. This simple and versatile procedure is not dye-exclusive and is therefore extendable to other molecular systems for color-tunable efficient solid-state lighting sources. PMID:24638041

  5. Straightforward fabrication of stable white LEDs by embedding of inorganic UV-LEDs into bulk polymerized polymethyl-methacrylate doped with organic dyes

    NASA Astrophysics Data System (ADS)

    di Martino, Daniela; Beverina, Luca; Sassi, Mauro; Brovelli, Sergio; Tubino, Riccardo; Meinardi, Francesco

    2014-03-01

    Stable white-emitting down-converted LEDs are straightforwardly prepared by bulk polymerization of an organic dye doped polymethyl-methacrylate (PMMA) shell directly on top of a highly efficient commercial blue-emitting InGaN LED. Our optimized polymerization procedure allows for extending the form factor of achievable luminescence converter (LUCO) material beyond the conventional thin film form and to directly produce devices with light bulb design. The selected organic dyes, the blue-emitting Coumarin 30 and a red-emitting diketopyrrolopyrrole derivative, exhibit high compatibility with the free radical polymerization reaction of the PMMA matrix and ensure high stability of the final hybrid device. The control of both the thickness of the PMMA shell and the concentration of the dopant dyes allow for fine tuning of the emission color of the LUCO LED and to obtain white light with CIE chromatic coordinates x = 0.32 and y = 0.33, with rendering index as high as 80. This simple and versatile procedure is not dye-exclusive and is therefore extendable to other molecular systems for color-tunable efficient solid-state lighting sources.

  6. Medical Applications of White LEDs for Surgical Operation

    NASA Astrophysics Data System (ADS)

    Shimada, Junichi; Kawakami, Yoichi

    Everywhere in the world, the highest quality and quantity of lighting is required during the surgical operations. However, the surgical approach has had many types and various angles, common ceiling surgical halogen lighting system cannot provide an adequate amount of beams because the surgeons' heads hinder the illuminations from reaching the operation field. The evolution of solid-state-lighting is currently going to be developed due to the progress of white light emitting diodes (LEDs). We proposed and developed the new lighting equipment that is a surgical lighting goggle composed of InGaN-YAG (yttrium aluminum garnet):Ce3+-based white LEDs. Here, we newly design surgical lighting system composed of white LEDs equipped on both sides of goggles. In fact, we have succeeded in the first internal shunt operation in the left forearm using the surgical LED lighting system on 11th Sept 2000. Since the white LEDs used were composed of InGaN-blue-emitters and YAG-yellow-phosphors, the color rendering property was not sufficient in the reddish colors. After our first challenge for medical application of white LEDs, we have been trying to improve the luminance power of white LED, the color rendering in red colors and the spectral distribution of white LED to render inherent color of raw flesh such as skin, blood, fat tissue and internal organs. We have produced new concepts for LED lighting sources and new several generations of LED lighting goggles.

  7. LED light engine concept with ultra-high scalable luminance

    NASA Astrophysics Data System (ADS)

    Hoelen, Christoph; de Boer, Dick; Bruls, Dominique; van der Eyden, Joost; Koole, Rolf; Li, Yun; Mirsadeghi, Mo; Vanbroekhoven, Vincent; Van den Bergh, John-John; Van de Voorde, Patrick

    2016-03-01

    Although LEDs have been introduced successfully in many general lighting applications during the past decade, high brightness light source applications are still suffering from the limited luminance of LEDs. High power LEDs are generally limited in luminance to ca 100 Mnit (108 lm/m2sr) or less, while dedicated devices for projection may achieve luminance values up to ca 300 Mnit with phosphor converted green. In particular for high luminous flux applications with limited étendue, like in front projection systems, only very modest luminous flux values in the beam can be achieved with LEDs compared to systems based on discharge lamps. In this paper we introduce a light engine concept based on a light converter rod pumped with blue LEDs that breaks through the étendue and brightness limits of LEDs, enabling LED light source luminance values that are more than 4 times higher than what can be achieved with LEDs so far. In LED front projection systems, green LEDs are the main limiting factor. With our green light emitting modules, peak luminance values well above 1.2 Gnit have been achieved, enabling doubling of the screen brightness of LED based DLP projection systems, and even more when this technology is applied to other colors as well. This light source concept, introduced as the ColorSpark High Lumen Density (HLD) LED technology, enables a breakthrough in the performance of LED-based light engines not only for projection, where >2700 ANSI lm was demonstrated, but for a wide variety of high brightness applications.

  8. Commercial jet transport crashworthiness

    NASA Technical Reports Server (NTRS)

    Widmayer, E.; Brende, O. B.

    1982-01-01

    The results of a study to identify areas of research and approaches that may result in improved occupant survivability and crashworthiness of transport aircraft are given. The study defines areas of structural crashworthiness for transport aircraft which might form the basis for a research program. A 10-year research and development program to improve the structural impact resistance of general aviation and commercial jet transport aircraft is planned. As part of this program parallel studies were conducted to review the accident experience of commercial transport aircraft, assess the accident performance of structural components and the status of impact resistance technology, and recommend areas of research and development for that 10-year plan. The results of that study are also given.

  9. Differences in the structure of outpatient diabetes care between endocrinologist- led and general physician- led services

    PubMed Central

    2013-01-01

    Background Despite a shift in diabetes care internationally from secondary to primary care, diabetes care in the Republic of Ireland remains very hospital-based. Significant variation in the facilities and resources available to hospitals providing outpatient diabetes care have been reported in the UK. The aim of this study was to ascertain the structure of outpatient diabetes care in public hospitals in the Republic of Ireland and whether differences existed in services provided across hospitals. Methods We conducted a cross sectional observational study of the 36 public general hospitals providing adult outpatient diabetes care in the Republic of Ireland. Data relating to numbers of specialist medical, nursing and allied health professionals, waiting times for new and return patients, patterns of discharge back to primary care and engagement in quality improvement initiatives were recorded. Results Thirty-five of the 36 eligible hospitals participated in the study. Sixty percent of these had at least one consultant endocrinologist in post, otherwise care delivery was led by a general physician. Waiting times for newly diagnosed patients exceeded six months in 30% of hospitals and this was higher where an endocrinologist was in place (47% V 7%, p = 0.013). Endocrinologists were more likely to have developed subspecialty clinics, access to allied health professionals and engage more in quality improvement initiatives but less likely to discharge patients back to primary care than general physicians (76 v 29%, p = 0.005). Conclusions Variations exist in the structure and provision of diabetes care in Irish hospitals. Endocrinology-led services have more developed subspecialty structures and access to specialist allied health professionals and engage more in quality improvement initiatives. Nonetheless, waiting times are longer and discharge rates to primary care are lower than for non-specialty led services. Further studies to determine the extent to which

  10. European commercial aeronautics

    NASA Technical Reports Server (NTRS)

    Van Zandt, J Parker

    1925-01-01

    During the months of June to September, 1924, I personally visited the principal airports of Europe and traveled as a passenger some 6500 air miles on English, French, Romanian, Polish, German and Dutch air lines in order to investigate the development of commercial aviation abroad. The results of the investigation are embodied in a series of reports, of which a summary of the general findings is given below.

  11. Multiplexed coded illumination for Fourier Ptychography with an LED array microscope

    PubMed Central

    Tian, Lei; Li, Xiao; Ramchandran, Kannan; Waller, Laura

    2014-01-01

    Fourier Ptychography is a new computational microscopy technique that achieves gigapixel images with both wide field of view and high resolution in both phase and amplitude. The hardware setup involves a simple replacement of the microscope’s illumination unit with a programmable LED array, allowing one to flexibly pattern illumination angles without any moving parts. In previous work, a series of low-resolution images was taken by sequentially turning on each single LED in the array, and the data were then combined to recover a bandwidth much higher than the one allowed by the original imaging system. Here, we demonstrate a multiplexed illumination strategy in which multiple randomly selected LEDs are turned on for each image. Since each LED corresponds to a different area of Fourier space, the total number of images can be significantly reduced, without sacrificing image quality. We demonstrate this method experimentally in a modified commercial microscope. Compared to sequential scanning, our multiplexed strategy achieves similar results with approximately an order of magnitude reduction in both acquisition time and data capture requirements. PMID:25071971

  12. Introduction: Commercialization of Academic Science and a New Agenda for Science Education

    ERIC Educational Resources Information Center

    Irzik, Gürol

    2013-01-01

    Certain segments of science are becoming increasingly commercialized. This article discusses the commercialization of academic science and its impact on various aspects of science. It also aims to provide an introduction to the articles in this special issue. I briefly describe the major factors that led to this phenomenon, situate it in the…

  13. UV-LED exposure system for low-cost photolithography

    NASA Astrophysics Data System (ADS)

    Yapici, Murat Kaya; Farhat, Ilyas

    2014-03-01

    This paper reports the development of a low-cost, portable, light-emitting diode (LED)-based UV exposure system for photolithography. The major system components include UV-LEDs, microcontroller, digital-to-analog (D/A) converter and LED control circuitry. The UV-LED lithography system is also equipped with a digital user interface (LCD and keypad) and permits accurate electronic control on the exposure time and power. Hence the exposure dose can be varied depending on process requirements. Compared to traditional contact lithography, the UV-LED lithography system is significantly cheaper, simple to construct using off-the shelf components and does not require complex infrastructure to operate. Such reduction in system cost and complexity renders UV-LED lithography as a perfect candidate for micro lithography with large process windows typically suitable for MEMS, microfluidics applications.

  14. Nonuniformity correction in LED printing with plural resolution recording

    NASA Astrophysics Data System (ADS)

    Ng, Yee S.; Pham, Hieu T.; Laird, Robert

    1990-08-01

    Binary LED printbars in general have exposure non-uniformity associated with lens transmission nonuniformity LED brightness variations and electro-optical crosstalks (e. g. rise time degradation optical power starvation cross-talk noise as a function of LED pixels usage) that need to be corrected for a high quality printing system. We have designed a constant current Si driver array with two independent power supplies (logic and LED powers) coupled with an improved LED printhbar system to minimize the cross-talk artifacts. In order to improve on the average exposure uniformity of the LED printing system individual trimmable current source to each driver array is also provided. In addition to that a plural resolution printing method (400 x 2400) with a binary weighted correction scheme is used to reduce a binary printhbar''s printing non-uniformity of + or-iS to + or- 1. 0. 1.

  15. A novel amblyopia treatment system based on LED light source

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaoqing; Chen, Qingshan; Wang, Xiaoling

    2011-05-01

    A novel LED (light emitting diode) light source of five different colors (white, red, green, blue and yellow) is adopted instead of conventional incandescent lamps for an amblyopia treatment system and seven training methods for rectifying amblyopia are incorporated so as for achieving an integrated therapy. The LED light source is designed to provide uniform illumination, adjustable light intensity and alterable colors. Experimental tests indicate that the LED light source operates steadily and fulfills the technical demand of amblyopia treatment.

  16. A novel amblyopia treatment system based on LED light source

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaoqing; Chen, Qingshan; Wang, Xiaoling

    2010-12-01

    A novel LED (light emitting diode) light source of five different colors (white, red, green, blue and yellow) is adopted instead of conventional incandescent lamps for an amblyopia treatment system and seven training methods for rectifying amblyopia are incorporated so as for achieving an integrated therapy. The LED light source is designed to provide uniform illumination, adjustable light intensity and alterable colors. Experimental tests indicate that the LED light source operates steadily and fulfills the technical demand of amblyopia treatment.

  17. LED Arrays as Cost Effective and Efficient Light Sources for Widefield Microscopy

    PubMed Central

    Sato, Tomokazu F.; Meister, Markus; Murthy, Venkatesh N.

    2008-01-01

    New developments in fluorophores as well as in detection methods have fueled the rapid growth of optical imaging in the life sciences. Commercial widefield microscopes generally use arc lamps, excitation/emission filters and shutters for fluorescence imaging. These components can be expensive, difficult to maintain and preclude stable illumination. Here, we describe methods to construct inexpensive and easy-to-use light sources for optical microscopy using light-emitting diodes (LEDs). We also provide examples of its applicability to biological fluorescence imaging. PMID:18478056

  18. Excellent color rendering indexes of multi-package white LEDs.

    PubMed

    Oh, Ji Hye; Yang, Su Ji; Sung, Yeon-Goog; Do, Y R

    2012-08-27

    This study introduces multi-package white light-emitting diodes (LEDs) system with the ability to realize high luminous efficacy and an excellent color rendering index (CRI, R a) using the R B,M A B,M G B,M C B (R B,M A B,M G B,M denoted as a long-pass dichroic filter (LPDF)-capped, monochromatic red, amber and green phosphor converted-LED (pc-LED) pumped by a blue LED chip, and C B denoted as a cyan and blue mixed pc-LED pumped by a blue LED) system. The luminous efficacy and color rendering index (CRI) of multi-package white LED systems are compared while changing the concentration of the cyan phosphor used in the paste of a cyan-blue LED package and the driving current of individual LEDs in multi-package white LEDs at correlated color temperatures (CCTs) ranging from 6,500 K (cold white) to 2,700 K (warm white) using a set of eight CCTs as specified by the American National Standards Institute (ANSI) standard number C78.377-2008. A R B,M A B,M G B,M C B white LED system provides high luminous efficacy (≥ 96 lm/W) and a color rendering index (≥ 91) encompassing the complete CCT range. We also compare the optical properties of the R B,M A B,M G B,M C B system with those of the R B,M A B,M G B,M B and RAGB (red, amber, green, and blue semiconductor-type narrow-spectrum-band LEDs) systems. It can be expected that the cyan color added to a blue LED in multi-package white LEDs based on LPDF-capped, phosphor-converted monochromatic LEDs will meet the needs of the high-quality, highly efficient, full-color white LED lighting market in the near future. PMID:23037079

  19. High-Modulation-Speed LEDs Based on III-Nitride

    NASA Astrophysics Data System (ADS)

    Chen, Hong

    III-nitride InGaN light-emitting diodes (LEDs) enable wide range of applications in solid-state lighting, full-color displays, and high-speed visible-light communication. Conventional InGaN quantum well LEDs grown on polar c-plane substrate suffer from quantum confined Stark effect due to the large internal polarization-related fields, leading to a reduced radiative recombination rate and device efficiency, which limits the performance of InGaN LEDs in high-speed communication applications. To circumvent these negative effects, non-trivial-cavity designs such as flip-chip LEDs, metallic grating coated LEDs are proposed. This oral defense will show the works on the high-modulation-speed LEDs from basic ideas to applications. Fundamental principles such as rate equations for LEDs/laser diodes (LDs), plasmonic effects, Purcell effects will be briefly introduced. For applications, the modal properties of flip-chip LEDs are solved by implementing finite difference method in order to study the modulation response. The emission properties of highly polarized InGaN LEDs coated by metallic gratings are also investigated by finite difference time domain method.

  20. Rapid fabrication of microfluidic chips based on the simplest LED lithography

    NASA Astrophysics Data System (ADS)

    Li, Yue; Wu, Ping; Luo, Zhaofeng; Ren, Yuxuan; Liao, Meixiang; Feng, Lili; Li, Yuting; He, Liqun

    2015-05-01

    Microfluidic chips are generally fabricated by a soft lithography method employing commercial lithography equipment. These heavy machines require a critical room environment and high lamp power, and the cost remains too high for most normal laboratories. Here we present a novel microfluidics fabrication method utilizing a portable ultraviolet (UV) LED as an alternative UV source for photolithography. With this approach, we can repeat several common microchannels as do these conventional commercial exposure machines, and both the verticality of the channel sidewall and lithography resolution are proved to be acceptable. Further microfluidics applications such as mixing, blood typing and microdroplet generation are implemented to validate the practicability of the chips. This simple but innovative method decreases the cost and requirement of chip fabrication dramatically and may be more popular with ordinary laboratories.

  1. DOE acceptance of commercial mixed waste -- Studies are under way

    SciTech Connect

    Plummer, T.L.; Owens, C.M.

    1993-03-01

    The topic of the Department of Energy acceptance of commercial mixed waste at DOE facilities has been proposed by host States and compact regions that are developing low-level radioactive waste disposal facilities. States support the idea of DOE accepting commercial mixed waste because (a) very little commercial mixed waste is generated compared to generation by DOE facilities (Department of Energy--26,300 cubic meters annually vs. commercial--3400 cubic meters annually); (b) estimated costs for commercial disposal are estimated to be $15,000 to $40,000 per cubic foot; (c) once treatment capability becomes available, 70% of the current levels of commercial mixed waste will be eliminated, (d) some State laws prohibit the development of mixed waste disposal facilities in their States; (e) DOE is developing a nationwide strategy that will include treatment and disposal capacity for its own mixed waste and the incremental burden on the DOE facilities would be minuscule, and (6) no States are developing mixed waste disposal facilities. DOE senior management has repeatedly expressed willingness to consider investigating the feasibility of DOE accepting commercial mixed waste. In January 1991, Leo Duffy of the Department of energy met with members of the Low-Level Radioactive Waste Forum, which led to an agreement to explore such an arrangement. He stated that this seems like a cost-effective way to solve commercial mixed waste management problems.

  2. Horizontally assembled green InGaN nanorod LEDs: scalable polarized surface emitting LEDs using electric-field assisted assembly

    PubMed Central

    Park, Hoo Keun; Yoon, Seong Woong; Eo, Yun Jae; Chung, Won Woo; Yoo, Gang Yeol; Oh, Ji Hye; Lee, Keyong Nam; Kim, Woong; Do, Young Rag

    2016-01-01

    In this study, we report the concerted fabrication process, which is easy to transform the size of active emitting area and produce polarized surface light, using the electric-field-assisted assembly for horizontally assembled many tiny nanorod LEDs between two metal electrodes. We fabricate the millions of individually separated 1D nanorod LEDs from 2D nanorod arrays using nanosphere lithography, etching and cutting process of InGaN/GaN LED structure on a flat sapphire substrate. The horizontally assembled InGaN-based nanorods LED device shows bright (~2,130 cd/m2) and uniform polarized (polarization ratio, ρ = ~0.61) green emissions from large area (0.7 cm × 0.6 cm) planar surface. The realization of a horizontally assembled nanorod LED device can prove the concept of an innovative idea to fabricate formable and scalable polarized surface LED lighting. PMID:27324568

  3. Horizontally assembled green InGaN nanorod LEDs: scalable polarized surface emitting LEDs using electric-field assisted assembly

    NASA Astrophysics Data System (ADS)

    Park, Hoo Keun; Yoon, Seong Woong; Eo, Yun Jae; Chung, Won Woo; Yoo, Gang Yeol; Oh, Ji Hye; Lee, Keyong Nam; Kim, Woong; Do, Young Rag

    2016-06-01

    In this study, we report the concerted fabrication process, which is easy to transform the size of active emitting area and produce polarized surface light, using the electric-field-assisted assembly for horizontally assembled many tiny nanorod LEDs between two metal electrodes. We fabricate the millions of individually separated 1D nanorod LEDs from 2D nanorod arrays using nanosphere lithography, etching and cutting process of InGaN/GaN LED structure on a flat sapphire substrate. The horizontally assembled InGaN-based nanorods LED device shows bright (~2,130 cd/m2) and uniform polarized (polarization ratio, ρ = ~0.61) green emissions from large area (0.7 cm × 0.6 cm) planar surface. The realization of a horizontally assembled nanorod LED device can prove the concept of an innovative idea to fabricate formable and scalable polarized surface LED lighting.

  4. Horizontally assembled green InGaN nanorod LEDs: scalable polarized surface emitting LEDs using electric-field assisted assembly.

    PubMed

    Park, Hoo Keun; Yoon, Seong Woong; Eo, Yun Jae; Chung, Won Woo; Yoo, Gang Yeol; Oh, Ji Hye; Lee, Keyong Nam; Kim, Woong; Do, Young Rag

    2016-01-01

    In this study, we report the concerted fabrication process, which is easy to transform the size of active emitting area and produce polarized surface light, using the electric-field-assisted assembly for horizontally assembled many tiny nanorod LEDs between two metal electrodes. We fabricate the millions of individually separated 1D nanorod LEDs from 2D nanorod arrays using nanosphere lithography, etching and cutting process of InGaN/GaN LED structure on a flat sapphire substrate. The horizontally assembled InGaN-based nanorods LED device shows bright (~2,130 cd/m(2)) and uniform polarized (polarization ratio, ρ = ~0.61) green emissions from large area (0.7 cm × 0.6 cm) planar surface. The realization of a horizontally assembled nanorod LED device can prove the concept of an innovative idea to fabricate formable and scalable polarized surface LED lighting. PMID:27324568

  5. High-Efficiency Non-Polar GaN-Based LEDs

    SciTech Connect

    Paul Fini

    2010-11-30

    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

  6. High-Power Warm-White Hybrid LED Package for Illumination

    SciTech Connect

    Soer, Wouter

    2013-09-19

    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

  7. Accelerating Commercial Remote Sensing

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Through the Visiting Investigator Program (VIP) at Stennis Space Center, Community Coffee was able to use satellites to forecast coffee crops in Guatemala. Using satellite imagery, the company can produce detailed maps that separate coffee cropland from wild vegetation and show information on the health of specific crops. The data can control coffee prices and eventually may be used to optimize application of fertilizers, pesticides and irrigation. This would result in maximal crop yields, minimal pollution and lower production costs. VIP is a mechanism involving NASA funding designed to accelerate the growth of commercial remote sensing by promoting general awareness and basic training in the technology.

  8. Commercialization Assistance Program

    SciTech Connect

    Jenny C Servo, Ph D

    2008-02-15

    The Commercialization Assistance Program (CAP) is offered to Phase II awardees of the Department of Energy's Small Business Innovation Research (SBIR) and Small Business Technology Transfer (STTR) programs. The purpose of this program is to increase both the likelihood and speed of technology transition to Phase III of technologies which DOE has funded. This program has been offered to DOE SBIR firms since 1990 and has resulted in significant and well documented return on investment. This final report decribes the results of the CAP that was offered to participants during the last cycle.

  9. LED white lights with high CRI and high luminous efficacy

    NASA Astrophysics Data System (ADS)

    He, Guoxing; Zheng, Lihong; Yan, Huafeng

    2010-11-01

    The models for spectra of a phosphor-coated white (p-W) LED and a white light LED cluster are developed based on the principle of additive color mixture. The simulation results show that p-W LEDs consisting of a blue chip (450nm), green phosphor (507 nm), yellow phosphor (580 nm) and red phosphor (655 nm) could realize color rendering indices (CRIs) above 97.7 and special CRIs of R1 to R14 above 91.1, but luminous efficacies of radiation (LERs) below 250.3 lm/W, that white/red clusters consisting of red LEDs and p-W LEDs with a blue chip (450nm), green (507 nm) and yellow (580 nm) phosphors could realize given color temperature white light with CRIs above 97.9 and special CRIs of R1 to R14 above 89.6, as well as LERs above 296.3 lm/W, and that a neutral-white /red//blue cluster consisting of blue LEDs (465 nm), red LEDs (628 nm) and neutral-white LEDs with a blue chip (452 nm), green (530 nm) and yellow (586 nm) phosphors could realize CCT tunable white lights with CRIs above 97.9 and special CRIs of R1 to R14 above 89.6, as well as LER above 296.3 lm/W.

  10. Design of new collection systems for multi LED light engines

    NASA Astrophysics Data System (ADS)

    Murat, Hüseyin; Cuypers, Dieter; De Smet, Herbert

    2006-04-01

    LED based projectors have numerous advantages compared to traditional projectors: they are more compact, exhibit a larger color gamut and a longer lifetime, the supply voltage is lower, the absence of ultra violet, infrared radiation and mercury vapour, etc. Furthermore LED's can switch on and off very rapidly (possibility to pulse them) and they have a high dimming ratio that can be used to improve the contrast. However, there is also an important disadvantage: the optical power per unit of etendue (luminance) of an LED is significantly lower than that of e.g. an UHP-lamp. Because of this and the etendue limitation of the projector (small light valve, f-number projection lens), the projected flux on the screen will not be high. Despite this shortcoming, LED's are still very interesting for low power applications because of their superior properties. However we have to collect the available light flux optimally and combine multiple LED's with high luminance within the available system etendue. In this paper we have studied collection optics that collect the LED flux with high optical efficiency and collimation and reshape the spot in a uniform illuminated rectangle with the sizes of the micro display. We have designed 'Gradually Tapered Light Pipes', 'Elliptical Reflectors' and 'Parabolic Reflectors'. Furthermore we have combined many of these LED/collector combinations to get a high luminance illumination engine for LED based projectors.

  11. Can a Teacher-Led State Assessment System Work?

    ERIC Educational Resources Information Center

    Bandalos, Deborah L.

    2004-01-01

    Recent implementation of Nebraska's Standards-based Teacher-led Assessment and Reporting System (STARS) introduced a unique opportunity to examine the benefits and drawbacks of a teacher-led state assessment system. STARS is unique among state assessment systems in that statewide tests are replaced by locally developed assessments designed by…

  12. Peer-led postgraduate education across medicine and psychiatry.

    PubMed

    Demir, Ozan M; Abdullah, Rezaur; Srivastava, Vivek

    2016-05-01

    Peer-led education is well established in undergraduate education, but there is a paucity of data regarding its role in postgraduate education. This article assesses the feasibility of peer-led teaching in postgraduate medical education and evaluates its benefits through qualitative structured feedback. PMID:27166105

  13. Low Cost Lithography Tool for High Brightness LED Manufacturing

    SciTech Connect

    Andrew Hawryluk; Emily True

    2012-06-30

    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.

  14. 76 FR 14904 - Executive-Led Trade Mission to Afghanistan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-18

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE International Trade Administration Executive-Led Trade Mission to Afghanistan AGENCY: International Trade..., Afghanistan in September 2011. This mission will be led by a Senior Commerce Department official....

  15. 76 FR 66692 - Executive-Led Trade Mission to Afghanistan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-27

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE International Trade Administration Executive-Led Trade Mission to Afghanistan AGENCY: International Trade..., Afghanistan in February 2012. This mission will be led by a Senior Commerce Department official....

  16. Automated hardware-software system for LED's verification and certification

    NASA Astrophysics Data System (ADS)

    Chertov, Aleksandr N.; Gorbunova, Elena V.; Peretyagin, Vladimir S.; Vakulenko, Anatolii D.

    2012-10-01

    Scientific and technological progress of recent years in the production of the light emitting diodes (LEDs) has led to the expansion of areas of their application from the simplest systems to high precision lighting devices used in various fields of human activity. However, for all technology development at the present time it is very difficult to choose one or another brand of LEDs for realization of concrete devices designed for the implementation of high precision spatial and color measurements of various objects. In the world there are many measurement instruments for determining the various parameters of LEDs, but none of them are not capable to estimate comprehensively the LEDs spatial, spectral, and color parameters with the necessary accuracy and speed. This problem can be solved by using an automated hardware-software system for LED's verification and certification, developed by specialists of the OEDS chair of National Research University ITMO in Russia. The paper presents the theoretical aspects of the analysis of LED's spatial, spectral and color parameters by using mentioned of automated hardware-software system. The article also presents the results of spatial, spectral, and color parameters measurements of some LEDs brands.

  17. Apprenticeship in the Instructor-Led Peer Conference

    ERIC Educational Resources Information Center

    Ching, Kory Lawson

    2011-01-01

    The instructor-led peer conference, a lesser-known approach to peer response involving both students and teachers, affords significant opportunities for collaborative learning and apprenticeship in the teaching of composition. This article uses sociocultural theories of learning to examine video-recorded episodes from two instructor-led peer…

  18. Overview of Commercial Buildings, 2003

    EIA Publications

    2008-01-01

    The Energy Information Administration conducts the Commercial Buildings Energy Consumption Survey (CBECS) to collect information on energy-related building characteristics and types and amounts of energy consumed in commercial buildings in the United States.

  19. Accelerating advanced-materials commercialization

    NASA Astrophysics Data System (ADS)

    Maine, Elicia; Seegopaul, Purnesh

    2016-05-01

    Long commercialization times, high capital costs and sustained uncertainty deter investment in innovation for advanced materials. With appropriate strategies, technology and market uncertainties can be reduced, and the commercialization of advanced materials accelerated.

  20. Automated platform for determination of LEDs spatial radiation pattern

    NASA Astrophysics Data System (ADS)

    Vladescu, Marian; Vuza, Dan Tudor

    2015-02-01

    Nowadays technologies lead to remarkable properties of the light-emitting diodes (LEDs), making them attractive for more and more applications, such as: interior and exterior lighting, outdoor LED panels, traffic signals, automotive (tail and brake lights, backlighting in dashboard and switches), backlighting of display panels, LCD displays, symbols on switches, keyboards, graphic boards and measuring scales. Usually, LEDs are small light sources consisting of a chip placed into a package, which may bring additional optics to this encapsulated ensemble, resulting in a less or more complex spatial distribution of the light intensity, with particular radiation patterns. This paper presents an automated platform designed to allow a quick and accurate determination of the spatial radiation patterns of LEDs encapsulated in various packages. Keywords: LED, luminous

  1. Lessons learned from two peer-led mutual support groups.

    PubMed

    Viverito, Kristen M; Cardin, Scott A; Johnson, Leigh Ann; Owen, Richard R

    2013-10-01

    This case report and analysis describe the formation of two peer-led mutual support groups conducted within the context of a Veterans Administration Medical Center. Based on our assessment of the success of one of these groups and the failure of the other, we offer several recommendations and suggestions to help promote this modality. More specifically, we hypothesize that such groups are more likely to be successful (1) if participants are transferred en masse from another group, (2) that, at least initially, housing the group in the same context as formal clinician-led groups or overlapping clinician-led and peer-led groups may help smooth the transition from authority-led treatment to a mutual peer support format, and finally, (3) that prior experiences in interpersonal process groups may promote the skills and cohesion to promote successful transition to mutual support. PMID:24004015

  2. Investigation of irradiance efficiency for LED phototherapy with different arrays

    NASA Astrophysics Data System (ADS)

    Chen, Hsi-Chao; Wu, Guo-Yang

    2010-12-01

    Red and yellow light emitting diodes (LEDs) are currently utilized as lighting sources during LED phototherapy. These LEDs were arranged on a disk with an external diameter of 70 mm with different arrays — radial, rhombus, square radial, and square rhombus arrays. The radial and square radial arrays had better irradiance efficiency than rhombus and square rhombus arrays by optical simulation. Additionally, the radial array had 76 sets of LEDs, but the square radial array had 100 sets. Thus, a mockup sample of radial array phototherapy was constructed for performance tests. The mixture efficiency of the radial array was observed at distances of 1-100 mm and lighting was well mixed when distance exceeded 50 mm by optical simulation. Irradiance variation with angle was approximated by experiment and theory at a treatment distance of 50 mm and 100 mm using the phototherapy mockup. The radial array was one good choice for LED phototherapy.

  3. Automatic measurement system for long term LED parameters

    NASA Astrophysics Data System (ADS)

    Budzyński, Łukasz; Zajkowski, Maciej

    2015-09-01

    During the past years significantly increased the number of LED models available on the market. However, not all of them have parameters which allow for use in professional lighting systems. The article discusses the international standards which should be met by modern LEDs. Among them, one of the most important parameters is factor of luminous flux decline in value during the operation of the LEDs. Its value is influenced by many factors, among others, the junction temperature of the diode and average and maximum values of supply current. Other important, for lighting reasons, parameters are stability of correlated color temperature and stability of chromaticity coordinates of the emitted light. The paper presents a system to measure luminous flux and colorimetric parameters of LEDs. Measurement system also allows for measuring a change in these parameters during operation of the LED.

  4. Indoor visual positioning system using LED and mobile phone

    NASA Astrophysics Data System (ADS)

    Gong, Yingkui; Shi, Zhengfa; Wang, Yuqi

    2016-01-01

    An indoor visual positioning system is proposed, which using four or more LED ceiling lamps and a mobile phone. A 4*4 photodiode array is attached to the mobile phone to receive the three-dimensional coordinates of the LED lamps via visible light communication, and the front camera of the mobile phone is used to receive the high resolution image of the LED lamps. The mobile phone's three-dimensional coordinates can be determined by matching the spot information and three-dimensional coordinates of the LED lamps with the image information provided by the mobile phone. An improved collinear equation model is proposed to build the mapping relationship between the three-dimensional coordinates of the LED lamps and the image information acquired by the front camera. A semi-physical simulation has been conducted and analyzed. The positioning scheme is proved to be valid and the positioning accuracy is up to decimeter level.

  5. Commercial Driver Medical Examinations

    PubMed Central

    Moffitt, Gary; Hanowski, Richard J.; Kales, Stefanos N.; Porter, Richard J.; Hegmann, Kurt T.

    2015-01-01

    Objective: The objective of this study was to assess relationships between body mass index (BMI) and comorbid conditions within a large sample of truck drivers. Methods: Commercial driver medical examination data from 88,246 commercial drivers between 2005 and 2012 were analyzed for associations between BMI, medical disorders, and driver certification. Results: Most drivers were obese (53.3%, BMI >30.0 kg/m2) and morbidly obese (26.6%, BMI >35.0 kg/m2), higher than prior reports. Obese drivers were less likely to be certified for 2 years and more likely to report heart disease, hypertension, diabetes mellitus, nervous disorders, sleep disorders, and chronic low back pain (all P < 0.0001). There are relationships between multiple potentially disqualifying conditions and increasing obesity (P < 0.0001). Morbid obesity prevalence increased 8.9% and prevalence of three or more multiple conditions increased fourfold between 2005 and 2012. Conclusions: Obesity is related to multiple medical factors as well as increasing numbers of conditions that limit driving certification. PMID:25710607

  6. Commercial Zone Melting Ingots

    NASA Astrophysics Data System (ADS)

    Zheng, Yun; Xie, Hongyao; Shu, Shengcheng; Yan, Yonggao; Li, Han; Tang, Xinfeng

    2014-06-01

    Bismuth telluride-based compounds have been extensively utilized for commercial application. However, thermoelectric materials must suffer numerous mechanical vibrations and thermal stresses while in service, making it equally important to discuss the mechanical properties, especially at high temperature. In this study, the compressive and bending strengths of Bi0.5Sb1.5Te3 commercial zone melting (ZM) ingots were investigated at 25, 100, and 200 °C, respectively. Due to the obvious anisotropy of materials prepared by ZM method, the effect of anisotropy on the strengths was also explored. Two-parameter Weibull distribution was employed to fit a series of values acquired by a universal testing machine. And digital speckle photography was applied to record the strain field evolution, providing visual observation of surface strain. The compressive and bending strengths along ZM direction were approximately three times as large as those perpendicular to the ZM direction independent of the temperature, indicating a weak van der Waals bond along the c axis.

  7. Aerocapacitor commercialization plan

    SciTech Connect

    1995-09-12

    The purpose of the Power-One Aerocapacitor Commercialization Plan is to communicate to members of management and to all employees the overall objectives of the corporation. Power-One, Inc., has participated in a US Federal Government Technology Reinvestment Project (TRP), entitled {open_quotes}Advanced Power Conversion based on the Aerocapacitor{close_quotes}: the project is a group effort, with Lawrence Livermore National Labs, GenCorp/Aerojet, PolyStor Corp. (a start-up company), and Power-One forming the consortium. The expected resulting technology is the {open_quotes}Aerocapacitor{close_quotes}, which possesses much higher performance levels than the usual capacitors on the market today. Power-One hopes to incorporate the Aerocapacitor into some of its products, hence enhancing their performance, as well as market privately-labeled aerocapacitors through its distribution channels. This document describes the details of Power-One`s plan to bring to market and commercialize the Aerocapacitor and Aerocapacitor-based products. This plan was formulated while Power-One was part of the Oerocap project. It has since pulled out of this project. What is presented in this plan is the work which was developed prior to the business decision to terminate this work.

  8. Commercial nuclear power 1990

    SciTech Connect

    Not Available

    1990-09-28

    This report presents the status at the end of 1989 and the outlook for commercial nuclear capacity and generation for all countries in the world with free market economies (FME). The report provides documentation of the US nuclear capacity and generation projections through 2030. The long-term projections of US nuclear capacity and generation are provided to the US Department of Energy's (DOE) Office of Civilian Radioactive Waste Management (OCRWM) for use in estimating nuclear waste fund revenues and to aid in planning the disposal of nuclear waste. These projections also support the Energy Information Administration's annual report, Domestic Uranium Mining and Milling Industry: Viability Assessment, and are provided to the Organization for Economic Cooperation and Development. The foreign nuclear capacity projections are used by the DOE uranium enrichment program in assessing potential markets for future enrichment contracts. The two major sections of this report discuss US and foreign commercial nuclear power. The US section (Chapters 2 and 3) deals with (1) the status of nuclear power as of the end of 1989; (2) projections of nuclear capacity and generation at 5-year intervals from 1990 through 2030; and (3) a discussion of institutional and technical issues that affect nuclear power. The nuclear capacity projections are discussed in terms of two projection periods: the intermediate term through 2010 and the long term through 2030. A No New Orders case is presented for each of the projection periods, as well as Lower Reference and Upper Reference cases. 5 figs., 30 tabs.

  9. MPRS (URBOT) commercialization

    NASA Astrophysics Data System (ADS)

    Ciccimaro, Donny; Baker, William; Hamilton, Ian; Heikkila, Leif; Renick, Joel

    2003-09-01

    The Man Portable Robotic System (MPRS) project objective was to build and deliver hardened robotic systems to the U.S. Army"s 10 Mountain Division in Fort Drum, New York. The system, specifically designed for tunnel and sewer reconnaissance, was equipped with visual and audio sensors that allowed the Army engineers to detect trip wires and booby traps before personnel entered a potentially hostile environment. The MPRS system has shown to be useful in government and military supported field exercises, but the system has yet to reach the hands of civilian users. Potential users in Law Enforcement and Border Patrol have shown a strong interest in the system, but robotic costs were thought to be prohibitive for law enforcement budgets. Through the Center for Commercialization of Advanced Technology (CCAT) program, an attempt will be made to commercialize the MPRS. This included a detailed market analysis performed to verify the market viability of the technologies. Hence, the first step in this phase is to fully define the marketability of proposed technologies in terms of actual market size, pricing and cost factors, competitive risks and/or advantages, and other key factors used to develop marketing and business plans.

  10. Industrial and commercial cogeneration

    SciTech Connect

    Not Available

    1983-02-01

    The central issues surrounding cogeneration are highlighted and OTA's findings on those issues are summarized. The context in which cogenerators will operate is reviewed, including the national energy situation, current electric utility operation, and the regulation and financing of cogeneration systems. An overview of the cogeneration technologies is presented, including their operating and fuel use characteristics, projected costs, and requirements for interconnection with the utility grid. The opportunities for cogeneration in industry, commercial buildings, and rural areas are analyzed. The impacts of cogeneration on electric utilities' planning and operation and on the environment, as well as on general economic and institutional factors such as capital requirements, employment, and the decentralization of energy supply are assessed. Policy considerations for the use of cogeneration technologies are discussed. The appendices include a description of the model used to analyze commercial cogeneration and of the methods used to calculate emissions balances for air quality analysis, as well as a glossary of terms and a list of abbreviations used. (MHR)

  11. Development of Advanced LED Phosphors by Spray-based Processes for Solid State Lighting

    SciTech Connect

    Cabot Corporation

    2007-09-30

    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.

  12. Designing low cost LED display for the billboard

    NASA Astrophysics Data System (ADS)

    Hong, Yi-Jian; Uang, Chii-Maw; Wang, Ping-Chieh; Ho, Zu-Sheng

    2011-10-01

    With quickly advance of the computer, microelectronics and photonics technologies, LED display panel becomes a new electronic advertising media. It can be used to show any information whatever characters or graphics. Most LED display panels are built of many Light-Emitting Diodes arranged in a matrix form. The display has many advantages such as low power, low cost, long life and high definition. Because the display panel is asked to show rich color, the LED display panel's driving system becomes very complex. The design methodology of LED display panel's driver becomes more and more important to meet the market requirements. Cost is always the most important issue in public market domain. In this paper, we report a design methodology of LED display panel's driver based on the microprocessor control unit (MCU) system and LED display controller IC, HT1632C, to control three colors, RGB, color LED display panel and the modular panel size is 24*16 in matrix form. The HT1632C is a memory mapping LED display controller, it can be used on many applications, such as digital clock, thermometer, counter, voltmeter or other instrumentation readouts. Three pieces of HT1632C are used to drive a 24*16 RGB LED display panel, in our design case. Each HT163C chip is used to control one of the R, G and B color. As the drive mode is driven in DC mode, the RGB display panel can create and totally of seven colors under the control of MCU. The MCU generates the control signal to drive HT1632C. In this study, the software design methodology is adopted with dynamic display principle. When the scan frequency is 60Hz, LED display panel will get the clear picture and be able to display seven colors.

  13. Parent, Student, and Teacher Perceptions of Student-Led Conferences and Strategies to Host Effective Student-Led Conferences

    ERIC Educational Resources Information Center

    Jackson, Sharon M.

    2012-01-01

    This is a mixed-methods case study designed to examine the perceptions parents, students and teachers have about student-led conferences with the purpose of informing practices at the researcher's school as well as sharing strategies used to host effective student-led conferences. Parents and students were interviewed and surveyed. Teachers were…

  14. The commercialization of migration.

    PubMed

    Abrera-mangahas, M A

    1989-01-01

    International migration is not new to the Philippines. In the recent outflow of contract workers to the Middle East, there is a shift from individual and family initiated migrations to the more organized, highly commercial variety. While profit-taking intermediaries have played some role in the past, the increase in the number and influence of these intermediaries has altered the story of migration decision-making. In 1975, the signing of the bilateral labor agreement between the governments of Iran and the Philippines signalled the rising demand for Filipino contract workers. From 1970 to 1975, the number of Asian migrant workers in the Gulf countries rose from about 120,000 to 370,000. These figures rose dramatically to 3.3 million in 1985. The growing share of organized and commercialized migration has altered migration decision making. Primarily, intermediaries are able to broaden access to foreign job and high wage opportunities. Commercialization effectively raises the transaction costs for contract migration. Studies on recruitment costs and fees show that self-solicited foreign employment costs less than employment obtained through recruitment agents and intermediaries. The difference in the 2 prices is due, not only to overhead costs of intermediation, but more importantly to the rent exacted by agents from having job information and placement rights. In the Philippines in October 1987 the average placement fee was P8000, greatly exceeding the mandated maximum fee level of P5000. This average is understated because the computation includes the 17% who do not pay any fees. The widespread and popular view of recruitment intermediaries is negative, dominated by images of abuses and victims. Private intermediaries and the government bureaucracy need each other. Intermediaries need government; their consistent demand for incentives and protection is indicative. On the other hand, government expands its supervision of control of overseas employment via the

  15. Parent-led or baby-led? Associations between complementary feeding practices and health-related behaviours in a survey of New Zealand families

    PubMed Central

    Cameron, Sonya L; Taylor, Rachael W; Heath, Anne-Louise M

    2013-01-01

    Objective To determine feeding practices and selected health-related behaviours in New Zealand families following a ‘baby-led’ or more traditional ‘parent-led’ method for introducing complementary foods. Design, setting and participants 199 mothers completed an online survey about introducing complementary foods to their infant. Participants were classified into one of four groups: ‘adherent baby-led weaning (BLW)’, the infant mostly or entirely fed themselves at 6–7 months; ‘self-identified BLW’, mothers reported following BLW at 6–7 months but were using spoon-feeding at least half the time; ‘parent-led feeding’, the mother reported not having tried BLW; and ‘unclassified method’, the mother reported they were not following BLW at 6–7 months but reported the infant mostly or entirely fed themselves at 6–7 months. Results 8% were following ‘adherent BLW’, 21% ‘self-identified BLW’ and 0% were following the ‘unclassified method’. Compared with ‘self-identified BLW’ and ‘parent-led feeding’, a higher proportion of the ‘adherent BLW’ met the WHO recommendations to exclusively breastfeed for 6 months and to introduce complementary foods at 6 months. The ‘adherent BLW’ group was more likely to have family foods (p=0.018), and less likely (p=0.002) to have commercially prepared baby food. Both BLW groups were more likely to share meals with the family compared with ‘parent-led feeding’. In contrast to ‘self-identified BLW’ and ‘parent-led feeding’, the ‘adherent BLW’ group did not offer iron-fortified cereal as a first food. Conclusions This study suggests that although many parents consider they follow BLW, a very few are following it strictly. The extent to which BLW was followed was associated with potential benefits (eg, sharing family meals) and risks (eg, low iron first foods) highlighting the importance for health professionals and researchers of accurately determining the

  16. Vision communications based on LED array and imaging sensor

    NASA Astrophysics Data System (ADS)

    Yoo, Jong-Ho; Jung, Sung-Yoon

    2012-11-01

    In this paper, we propose a brand new communication concept, called as "vision communication" based on LED array and image sensor. This system consists of LED array as a transmitter and digital device which include image sensor such as CCD and CMOS as receiver. In order to transmit data, the proposed communication scheme simultaneously uses the digital image processing and optical wireless communication scheme. Therefore, the cognitive communication scheme is possible with the help of recognition techniques used in vision system. By increasing data rate, our scheme can use LED array consisting of several multi-spectral LEDs. Because arranged each LED can emit multi-spectral optical signal such as visible, infrared and ultraviolet light, the increase of data rate is possible similar to WDM and MIMO skills used in traditional optical and wireless communications. In addition, this multi-spectral capability also makes it possible to avoid the optical noises in communication environment. In our vision communication scheme, the data packet is composed of Sync. data and information data. Sync. data is used to detect the transmitter area and calibrate the distorted image snapshots obtained by image sensor. By making the optical rate of LED array be same with the frame rate (frames per second) of image sensor, we can decode the information data included in each image snapshot based on image processing and optical wireless communication techniques. Through experiment based on practical test bed system, we confirm the feasibility of the proposed vision communications based on LED array and image sensor.

  17. Development of a Tunable LED-Based Colorimetric Source

    PubMed Central

    Brown, Steven W.; Santana, Carlos; Eppeldauer, George P.

    2002-01-01

    A novel, spectrally tunable light-source utilizing light emitting diodes (LEDs) for radiometric, photometric, and colorimetric applications is described. The tunable source can simulate standard sources and can be used as a transfer source to propagate photometric and colorimetric scales from calibrated reference instruments to test artifacts with minimal increase in uncertainty. In this prototype source, 40 LEDs with 10 different spectral distributions were mounted onto an integrating sphere. A voltage-to-current control circuit was designed and implemented, enabling independent control of the current sent to each set of four LEDs. The LEDs have been characterized for stability and dependence on drive current. The prototype source demonstrates the feasibility of development of a spectrally tunable LED source using LEDs with up to 40 different spectral distributions. Simulations demonstrate that such a source would be able to approximate standard light-source distributions over the visible spectral range—from 380 nm to 780 nm—with deviations on the order of 2 %. The tunable LED source can also simulate spectral distributions of special sources such as discharge lamps and display monitors. With this tunable source, a test instrument can be rapidly calibrated against a variety of different source distributions tailored to the anticipated uses of the artifact. Target uncertainties for the calibration of test artifacts are less than 2 % in luminance and 0.002 in chromaticity for any source distribution.

  18. Reliability test and failure analysis of high power LED packages

    NASA Astrophysics Data System (ADS)

    Zhaohui, Chen; Qin, Zhang; Kai, Wang; Xiaobing, Luo; Sheng, Liu

    2011-01-01

    A new type application specific light emitting diode (LED) package (ASLP) with freeform polycarbonate lens for street lighting is developed, whose manufacturing processes are compatible with a typical LED packaging process. The reliability test methods and failure criterions from different vendors are reviewed and compared. It is found that test methods and failure criterions are quite different. The rapid reliability assessment standards are urgently needed for the LED industry. 85 °C/85 RH with 700 mA is used to test our LED modules with three other vendors for 1000 h, showing no visible degradation in optical performance for our modules, with two other vendors showing significant degradation. Some failure analysis methods such as C-SAM, Nano X-ray CT and optical microscope are used for LED packages. Some failure mechanisms such as delaminations and cracks are detected in the LED packages after the accelerated reliability testing. The finite element simulation method is helpful for the failure analysis and design of the reliability of the LED packaging. One example is used to show one currently used module in industry is vulnerable and may not easily pass the harsh thermal cycle testing.

  19. Effect of electrophotographic processes on print quality in LED printers

    NASA Astrophysics Data System (ADS)

    Wyhof, John R.

    1990-08-01

    The advantage of LED electrophotographic page printers is closely linked to the the process parameters of the printer. The electrical and mechanical processes and material properties were analyzed with respect to the affect on the print quality. Most critical to the print quality for the LED array printer is the constancy of the light intensity since the elements in the array are each independent light sources. It was found that the spot size can change significantly if the light intensity varies. Halftone printing uses the spot size to space size ratio to create the grayscale. The light intensity variation between elements can be 20 in non-compensated LED head arrays. If the need for light intensity compensation can be eliminated then a significant cost reduction in the LED head can be achieved. However the parameters of the basic electrophotographic processes must be carefully selected to assure a constant spot size and optimum print quality. The development method toner properties and the portion of the photoreceptor discharge curve used have the strongest influence on the spot size and halftone print quality. Transfer fusing and mechanical parameters have minimal effect. 1. LED PRINTING PROCESS The advantages of the LED printing process for high speed electrophotographic printers are well known. 1 Recently several printer manufacturers have introduced electrophotographic LED printers in the lower speed range. When compared to the scanning laser beam or liquid crystal

  20. Commercial Generic Bioprocessing Apparatus

    NASA Technical Reports Server (NTRS)

    1998-01-01

    CGBA, a facility developed by BioServe Space Technologies, a NASA Commercial Generic Bioprocessing Space Center, allows a variety of sophisticated bioprocessing research to be performed using a common device. The Fluids Processing Apparatus is essentially a microgravity test tube that allows a variety of complex investigations to be performed in space. This is a glass barrel containing several chambers separated by rubber stoppers. Eight FPAs are placed together in a Group Activation Pack (GAP), which allows all of the research to be started simultaneously by turning a single crank. Eight GAPs, or similar-sized payloads, can be stored in a single CGBA temperature controlled locker, which now uses motor drives to automatically turn the cranks to start and stop experiments. On STS-95, research efforts cover eight major areas that will benefit Earth-based products ranging from the production of pharmaceuticals to fish hatcheries.

  1. Commercial Data Mining Software

    NASA Astrophysics Data System (ADS)

    Zhang, Qingyu; Segall, Richard S.

    This chapter discusses selected commercial software for data mining, supercomputing data mining, text mining, and web mining. The selected software are compared with their features and also applied to available data sets. The software for data mining are SAS Enterprise Miner, Megaputer PolyAnalyst 5.0, PASW (formerly SPSS Clementine), IBM Intelligent Miner, and BioDiscovery GeneSight. The software for supercomputing are Avizo by Visualization Science Group and JMP Genomics from SAS Institute. The software for text mining are SAS Text Miner and Megaputer PolyAnalyst 5.0. The software for web mining are Megaputer PolyAnalyst and SPSS Clementine . Background on related literature and software are presented. Screen shots of each of the selected software are presented, as are conclusions and future directions.

  2. LED traffic lights: New technology signals major energy savings

    SciTech Connect

    Houghton, D.

    1994-12-31

    Using light-emitting diode technology to replace incandescent lamps in traffic signals promises energy savings upwards of 60 percent for each of the estimated quarter of a million controlled intersections in the United States. LED units use only 9 to 25 watts instead of the 67 to 150 watts used by each incandescent lamp. Though their first cost is relatively high, energy savings result in paybacks of 1 to 5 years. LED retrofit kits are available for red signal disks and arrows, and installations in several states have proven successful, although minor improvements are addressing concerns about varying light output and controller circuitry. Retrofitting green lamps is not yet feasible, because color standards of the Institute of Traffic Engineers cannot be met with existing LED technology. Yellow lamps have such low duty factors (they`re on only 3 percent of the time) that retrofitting with LED signals is not cost-effective. LEDs last much longer than incandescents, allowing municipalities to not only reduce their electricity bills, but to save on maintenance costs as well. As further incentive, some utilities are beginning to implement rebate programs for LED traffic signal retrofits. Full approval of LED units is still awaited from the Institute of Traffic Engineers (ITE), the standard-setting body for traffic safety devices. Local and state governments ultimately decide what specifications to require for traffic lights, and the growing body of successful field experience with LEDs appears to be raising their comfort level with the technology. The California Department of Transportation is developing an LED traffic light specification, and two California utilities, Southern California Edison and Pacific Gas and Electric, have provided rebates for some pilot installations.

  3. LOW-COST LED LUMINAIRE FOR GENERAL ILLUMINATION

    SciTech Connect

    Lowes, Ted

    2014-07-31

    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.

  4. Monolithic LED arrays, next generation smart lighting sources

    NASA Astrophysics Data System (ADS)

    Lagrange, Alexandre; Bono, Hubert; Templier, François

    2016-03-01

    LED have become the main light sources of the future as they open the path for intelligent use of light in time, intensity and color. In many usages, strong energy economy is done by adjusting these properties. The smart lighting has three dimensions, energy efficiency brought by GaN blue emitting LEDs, integration of electronics, sensors, microprocessors in the lighting system and development of new functionalities and services provided by the light. Monolithic LED arrays allow two major innovations, the spatial control of light emission and the adjustment of the electrical properties of the source.

  5. Integrated slanted microneedle-LED array for optogenetics.

    PubMed

    Kwon, Ki Yong; Khomenko, Anton; Haq, Mahmoodul; Li, Wen

    2013-01-01

    This paper presents a three-dimensional (3-D) flexible micro light emitting diode (μ-LED) array for selective optical stimulation of cortical neurons. The array integrated individually addressable μ-LED chips with slanted polymer-based microneedle waveguides to allow precise light delivery to multiple cortical layers simultaneously. A droplet backside exposure method was developed to monolithically fabricate slanted microneedles on a single polymer platform. A wafer-level assembly technique was demonstrated, which permits large-scale, high-density system integration. The electrical, optical, thermal, and mechanical properties of the 3-D slanted microneedle-LED array were characterized experimentally. PMID:24109671

  6. Optimized Phosphors for Warm White LED Light Engines

    SciTech Connect

    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

    2012-07-30

    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.

  7. The possible ocular hazards of LED dental illumination applications.

    PubMed

    Stamatacos, Catherine; Harrison, Janet L

    2013-01-01

    The use of high-intensity illumination via Light-Emitting Diode (LED) headlamps is gaining in popularity with dentists and student dentists. Practitioners are using LED headlamps together with magnifying loupes, overhead LED illumination and fiber-optic dental handpieces for long periods of time. Although most manufacturers of these LED illuminators advertise that their devices emit "white" light, these still consist of two spectral bands--the blue spectral band, with its peak at 445 nm, and the green with its peak at 555 nm. While manufacturers suggest that their devices emit "white" light, spectral components of LED lights from different companies are significantly different. Dental headlamp manufacturers strive to create a white LED, and they advertise that this type of light emitted from their product offers bright white-light illumination. However, the manufacturing of a white LED light is done through selection of a white LED-type based on the peak blue strength in combination with the green peak strength and thus creating a beam-forming optic, which determines the beam quality. Some LED illuminators have a strong blue-light component versus the green-light component. Blue-light is highly energized and is close in the color spectrum to ultraviolet-light. The hazards of retinal damage with the use of high-intensity blue-lights has been well-documented. There is limited research regarding the possible ocular hazards of usage of high-intensity illuminating LED devices. Furthermore, the authors have found little research, standards, or guidelines examining the possible safety issues regarding the unique dental practice setting consisting of the combined use of LED illumination systems. Another unexamined component is the effect of high-intensity light reflective glare and magnification back to the practitioner's eyes due to the use of water during dental procedures. Based on the result of Dr. Janet Harrison's observations of beginning dental students in a

  8. The possible ocular hazards of LED dental illumination applications.

    PubMed

    Stamatacos, Catherine; Harrison, Janet L

    2014-04-01

    The use of high-intensity illumination via Light-Emitting Diode (LED) headlamps is gaining in popularity with dentists and student dentists. Practitioners are using LED headlamps together with magnifying loupes, overhead LED illumination and fiber-optic dental handpieces for long periods of time. Although most manufacturers of these LED illuminators advertise that their devices emit "white" light, these still consist of two spectral bands - the blue spectral band, with its peak at 445 nm, and the green with its peak at 555 nm. While manufacturers suggest that their devices emit "white" light, spectral components of LED lights from different companies are significantly different. Dental headlamp manufacturers strive to create a white LED, and they advertise that this type of light emitted from their product offers bright white-light illumination. However, the manufacturing of a white LED light is done through selection of a white LED-type based on the peak blue strength in combination with the green peak strength and thus creating a beam-forming optic, which determines the beam quality. Some LED illuminators have a strong blue-light component versus the green-light component. Blue-light is highly energized and is close in the color spectrum to ultraviolet-light. The hazards of retinal damage with the use of high-intensity blue-lights has been well-documented. There is limited research regarding the possible ocular hazards of usage of high-intensity illuminating LED devices. Furthermore, the authors have found little research, standards, or guidelines examining the possible safety issues regarding the unique dental practice setting consisting of the combined use of LED illumination systems. Another unexamined component is the effect of high-intensity light reflective glare and magnification back to the practitioner's eyes due to the use of water during dental procedures. Based on the result of Dr. Janet Harrison's observations of beginning dental students in a

  9. University of Nevada Las Vegas LED Display Engineering

    SciTech Connect

    2010-08-31

    The primary objective of this part of the project is to develop and implement a method that compensates for the inefficiency of the green LED. The proposed engineering solution which will be the backbone of this project will be to use RGBW combination in every pixel to save energy. Two different RGBW geometrical pixel configurations will be implemented and compared against traditional LED configurations. These configurations will be analyzed for energy efficiency while keeping the quality of the display the same. Cost of the addition of white LEDs to displays along with energy cost savings will be presented and analyzed.

  10. A portable inspection system to estimate direct glare of various LED modules

    NASA Astrophysics Data System (ADS)

    Chen, Po-Li; Liao, Chun-Hsiang; Li, Hung-Chung; Jou, Shyh-Jye; Chen, Han-Ting; Lin, Yu-Hsin; Tang, Yu-Hsiang; Peng, Wei-Jei; Kuo, Hui-Jean; Sun, Pei-Li; Lee, Tsung-Xian

    2015-07-01

    Glare is caused by both direct and indirect light sources and discomfort glare produces visual discomfort, annoyance, or loss in visual performance and visibility. Direct glare is caused by light sources in the field of view whereas reflected glare is caused by bright reflections from polished or glossy surfaces that are reflected toward an individual. To improve visual comfort of our living environment, a portable inspection system to estimate direct glare of various commercial LED modules with the range of color temperature from 3100 K to 5300 K was developed in this study. The system utilized HDR images to obtain the illumination distribution of LED modules and was first calibrated for brightness and chromaticity and corrected with flat field, dark-corner and curvature by the installed algorithm. The index of direct glare was then automatically estimated after image capturing, and the operator can recognize the performance of LED modules and the possible effects on human being once the index was out of expecting range. In the future, we expect that the quick-response smart inspection system can be applied in several new fields and market, such as home energy diagnostics, environmental lighting and UGR monitoring and popularize it in several new fields.

  11. Color uniformity and data simulation in high-power RGB LED modules using different LED-chips arrays

    NASA Astrophysics Data System (ADS)

    Tu, Yan; Jin, Shangzhong; Wang, Yanhua; Dou, Liangliang

    2007-11-01

    The continuing research efforts in white light created by mixing red, green and blue light emitting diodes (RGB LED) will allow their applications in high quality lighting systems in the (near) future. There are still many issues to tackle in this kind of light source, for instance the color uniformity and the change of color-render property owing to the change of LED's temperature. In this paper we simulate the effects on color uniformity of the near-field light distribution due to different LED-chips arrays (at optimum packaging density for uniform irradiance) using High-Power RGB LED-chips. The results showing the color uniformity of near-field which can be achieved with different RGB LED-chips arrays are presented. Several configurations of RGB LED-chips arrays and relevant data for color variation are given respectively. An analysis of luminous efficacy of radiation (LER) and color rendering index (CRI) of this source is performed, which are affected by the peak wavelength, spectral width, and the output peak emission power ratio of LED-chips.

  12. On the spectral quality of scanner illumination with LEDs

    NASA Astrophysics Data System (ADS)

    Cui, Chengwu

    2013-01-01

    Document scanner illumination has evolved along with general illumination technologies. LEDs have become more and more popular as the illumination sources for document scanning. LED technologies provide a wide range of choices both in terms of structural design and spectral compositions. In this report, we examine some popular LED technologies used for document scanner. We evaluate the color rendering performance of scanner models with different illumination technologies by examining their rendering of the Macbeth ColorChecker™ in sRGB. We found that more phosphors in phosphor conversion types of white LEDs may not be necessarily advantageous in terms of scanner color rendering performance. Also CIS type of scanner may be sensitive to the peak wavelength shift and can be particularly problematic when the peaks are out of certain range.

  13. Novel Thermoelectric Modules for Cooling Powerful LEDs: Experimental Results

    NASA Astrophysics Data System (ADS)

    Semenyuk, V.; Dekhtiaruk, R.

    2013-07-01

    We present the results of an experimental study of a cooling system based on a novel thermoelectric module specifically designed for thermal management of high-power light-emitting diodes (LEDs). The Seoul Semiconductor LED W724C0 device was chosen for experimental validation of the efficiency of the proposed cooling unit. Two cooling systems with identical heat sinks were tested for comparison: a state-of-the-art one based on an insulated metal substrate-printed circuit board (IMS-PCB), and a system with thermoelectric cooling. The obtained results show that use of thermoelectrics results in a considerable reduction of the LED operating temperature, providing increased light output and greatly increased LED lifetime.

  14. Optics designs for an innovative LED lamp family system

    NASA Astrophysics Data System (ADS)

    Weiss, Herbert; Muschaweck, Julius; Hadrath, Stefan; Kudaev, Sergey

    2011-10-01

    On the general lighting market of LED lamps for professional applications there are still mainly products for single purpose solutions existing. There is a lack of standardised lamp systems like they are common for conventional lighting technologies. Therefore, an LED lamp family system was studied using high power LED with the objective to entirely substitute standard conventional lamp families in general lighting applications in the professional market segment. This comprises the realization of sets of lamp types with compact and linear shapes as well as with light distribution characteristics ranging from diffuse to extreme collimation and exceptionally high candle power. Innovative secondary optics concepts are discussed which allow both, the design of lamps with non-bulky shape and to obtain sufficient colour mixing when using multicolour LED combinations in order to achieve a very high colour rendering quality.

  15. National Consortium Supports Cities in Evaluating LED Streetlights

    SciTech Connect

    2013-09-30

    Fact sheet that introduces Municipal Solid-State Street Lighting Consortium, a group of municipalities, utilities, and energy efficiency organizations who are interested in making investments in LED street and area lighting.

  16. Remote phosphor LED modules for general illumination: toward 200 lm/W general lighting LED light sources

    NASA Astrophysics Data System (ADS)

    Hoelen, Christoph; Borel, Huub; de Graaf, Jan; Keuper, Matthijs; Lankhorst, Martijn; Mutter, Claudia; Waumans, Lars; Wegh, René

    2008-08-01

    Phosphor converted white LEDs are becoming more and more attractive for general lighting applications because of the steadily increasing luminous efficacy numbers reported by LED-suppliers. Despite these high numbers, a further significant improvement step can be made when a low-to-medium brightness (<500 kCd/m2) source is acceptable. The wall plug efficiency of a blue LED is generally better than that of a conventional white LED made from the same die. To take full advantage of this, we have developed medium-brightness LED-modules (~150 kCd/m2) for general lighting in which the phosphor is applied remote from the blue LEDs. By direct comparison with modules in which conventional high power white LEDs with almost identical dies are applied, we have shown that on system level the remote phosphor modules can have up to 50% better efficacy. Using a downlight module as a carrier, we have shown that in the relevant color temperature range of 2700 to 4000K a high CRI (>80) can be obtained in combination with a high luminous efficacy, while the optical efficiency of the module can be over 85%. A module efficacy of over 100 lm/W at 4000K with CRI 80 seems to be within reach, with a long-term expectation of over 180 lm/W. The remote phosphor LED modules deliver well homogenized white light with a Lambertian radiation profile. They are ideal for general illumination, as they combine glare reduction with high system efficacy and enable high optical efficiencies of the luminaries. The RP modules enable forward compatibility by well defined interfaces and optical properties that are decoupled from the actual performance, form factor and number of LEDs in the module. The Philips Fortimo downlight system is based on this remote phosphor concept, featuring forward compatibility and a total system efficacy (including driver) of over 60 lm/W under operating conditions using currently available Luxeon Rebel emitters.

  17. Influence of the LED heterostructure on the degradation behavior of (InAlGa)N-based UV-B LEDs

    NASA Astrophysics Data System (ADS)

    Glaab, Johannes; Lobo Ploch, Neysha; Rass, Jens; Kolbe, Tim; Wernicke, Tim; Mehnke, Frank; Kuhn, Christian; Enslin, Johannes; Stölmacker, Christoph; Kueller, Viola; Knauer, Arne; Einfeldt, Sven; Weyers, Markus; Kneissl, Michael

    2016-02-01

    In this paper we report on the influence of the heterostructure design of (InAlGa)N-based UV-B LEDs grown by metalorganic vapor phase epitaxy on sapphire substrates on the degradation behavior of the device. Two types of LEDs with different heterostructure design, resulting in peak-wavelengths of about 290 nm and 310 nm, respectively, were stressed at a constant operation current of 100 mA and a heat sink temperature of 20°C. Electro-optical characterization of the LEDs over 1.000 h of operation shows two different degradation modes with respect to the change of the emission spectrum and leakage current. The first mode during the initial hours (290 nm LED: 0 h - 500 h, 310 nm LED: 0 h - 100 h) of operation is represented by a fast reduction of the quantum well (QW) luminescence, a constant or increasing parasitic luminescence between 310 nm and 450 nm and a fast increase of the reverse- and forward-bias leakage current. These changes are more pronounced (higher degradation rate) in the 290 nm LEDs and can therefore be attributed to the different heterostructure design. In contrast, the second degradation mode at longer operation times (290 nm LED: >500 h, 310 nm LED: >100 h) is marked by a slow reduction of both the QW and the parasitic luminescence, as well as a slow increase of the leakage current which are similar for both types of LEDs. Furthermore, the second mode is marked by a square-root time dependence of the QW luminescence intensity, indicating a diffusion process to be involved.

  18. Biological Research in Canisters (BRIC) - Light Emitting Diode (LED)

    NASA Technical Reports Server (NTRS)

    Levine, Howard G.; Caron, Allison

    2016-01-01

    The Biological Research in Canisters - LED (BRIC-LED) is a biological research system that is being designed to complement the capabilities of the existing BRIC-Petri Dish Fixation Unit (PDFU) for the Space Life and Physical Sciences (SLPS) Program. A diverse range of organisms can be supported, including plant seedlings, callus cultures, Caenorhabditis elegans, microbes, and others. In the event of a launch scrub, the entire assembly can be replaced with an identical back-up unit containing freshly loaded specimens.

  19. Fabrication of Micro Lens Array by UV-LED Lithography

    NASA Astrophysics Data System (ADS)

    Iguchi, Yusuke; Matsumoto, Yoshinori

    High curvature micro lens array of 240-570 μm diameters and 110-270 μm heights has been fabricated by using UV-LED lithography and imprinting technique. Curved SU-8 structures were fabricated by backside exposure through thin glass substrate because UV-LED array light source has wide directivity characteristics of UV dose. The structure was transferred to Polydimethylsiloxsane (PDMS) mold. Micro lens array of photosensitive acrylic resin was fabricated by using the mold.

  20. Protection against methanol-induced retinal toxicity by LED photostimulation

    NASA Astrophysics Data System (ADS)

    Whelan, Harry T.; Wong-Riley, Margaret T. T.; Eells, Janis T.

    2002-06-01

    We have initiated experiments designed to test the hypothesis that 670-nm Light-Emitting Diode (LED) exposure will attenuate formate-induced retinal dysfunction in a rodent model of methanol toxicity. Methanol intoxication produces toxic injury to the retina. The toxic metabolite formed in methanol intoxication is formic acid, a mitochondrial toxin known to inhibit cytochrome oxidase activity. 670-nm LED light has been hypothesized to act by stimulating cytochrome oxidase activity. To test this hypothesis, one group of animals was intoxicated with methanol, a second group was intoxicated with methanol and LED-treated and a third group was untreated. LED treatment (670 nm for 1 min 45 seconds equals 50 mW/cm2, 4 joules/cm2) was administered at 5, 25, and 50 hours after the initial dose of methanol. At 72 hours of methanol intoxication, retinal function was assessed by measurement of ERG responses and retinas were prepared for histologic analysis. ERG responses recorded in methanol-intoxicated animals revealed profound attenuation of both rod-dominated and UV-cone mediated responses. In contrast, methanol- intoxicated animals exposed to LED treatment exhibited a nearly complete recovery of rod-dominated ERG responses and a slight improvement of UV-cone mediated ERG responses. LED treatment also protected the retina against the histopathologic changes produced by formate in methanol intoxication. These data provide evidence that LED phototherapy protects the retina against the cytotoxic actions of formate and are consistent with the hypothesis that LED photostimulation improves mitochondrial respiratory chain function.

  1. Integrated LED-based luminare for general lighting

    DOEpatents

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

    2013-03-05

    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.

  2. Integrated LED-based luminaire for general lighting

    DOEpatents

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

    2016-08-30

    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.

  3. Commercializing medical technology

    PubMed Central

    Lieberman, Mark A.

    2007-01-01

    As medicine moves into the 21st century, life saving therapies will move from inception into medical products faster if there is a better synergy between science and business. Medicine appears to have 50-year innovative cycles of education and scientific discoveries. In the 1880’s, the chemical industry in Germany was faced with the dilemma of modernization to exploit the new scientific discoveries. The solution was the spawning of novel technical colleges for training in these new chemical industries. The impact of those new employees and their groundbreaking compounds had a profound influence on medicine and medical education in Germany between 1880 and 1930. Germany dominated international science during this period and was a training center for scientists worldwide. This model of synergy between education and business was envied and admired in Europe, Asia and America. British science soon after evolved to dominate the field of science during the prewar and post World War (1930’s–1970’s) because the German scientists fled Hitler’s government. These expatriated scientists had a profound influence on the teaching and training of British scientists, which lead to advances in medicine such as antibiotics. After the Second World War, the US government wisely funded the development of the medical infrastructure that we see today. British and German scientists in medicine moved to America because of this bountiful funding for their research. These expatriated scientists helped drive these medical advances into commercialized products by the 1980’s. America has been the center of medical education and advances of biotechnology but will it continue? International scientists trained in America have started to return to Europe and Asia. These American-trained scientists and their governments are very aware of the commercial potential of biotechnology. Those governments are now more prepared to play an active role this new science. Germany, Ireland, Britain

  4. Intensity estimation method of LED array for visible light communication

    NASA Astrophysics Data System (ADS)

    Ito, Takanori; Yendo, Tomohiro; Arai, Shintaro; Yamazato, Takaya; Okada, Hiraku; Fujii, Toshiaki

    2013-03-01

    This paper focuses on a road-to-vehicle visible light communication (VLC) system using LED traffic light as the transmitter and camera as the receiver. The traffic light is composed of a hundred of LEDs on two dimensional plain. In this system, data is sent as two dimensional brightness patterns by controlling each LED of the traffic light individually, and they are received as images by the camera. Here, there are problems that neighboring LEDs on the received image are merged due to less number of pixels in case that the receiver is distant from the transmitter, and/or due to blurring by defocus of the camera. Because of that, bit error rate (BER) increases due to recognition error of intensity of LEDs To solve the problem, we propose a method that estimates the intensity of LEDs by solving the inverse problem of communication channel characteristic from the transmitter to the receiver. The proposed method is evaluated by BER characteristics which are obtained by computer simulation and experiments. In the result, the proposed method can estimate with better accuracy than the conventional methods, especially in case that the received image is blurred a lot, and the number of pixels is small.

  5. Compact LED based LCOS optical engine for mobile projection

    NASA Astrophysics Data System (ADS)

    Zhang, Wenzi; Li, Xiaoyan; Liu, Qinxiao; Yu, Feihong

    2009-11-01

    With the development of high power LED (light emitting diode) technology and color filter LCOS (liquid crystal on silicon) technology, the research on LED based micro optical engine for mobile projection has been a hot topic recently. In this paper one compact LED powered LCOS optical engine design is presented, which is intended to be embedded in cell phone, digital camera, and so on. Compared to DLP (digital light processor) and traditional color sequential LCOS technology, the color filter based LCOS panel is chosen for the compact optical engine, this is because only white LED is needed. To further decrease the size of the optical engine, only one specifically designed plastic free form lens is applied in the illumination part of the optical engine. This free form lens is designed so that it plays the roles of both condenser and integrator, by which the output light of LED is condensed and redistributed, and light illumination of high efficiency, high uniformity and small incident angle on LCOS is acquired. Besides PBS (polarization beam splitter), LCOS, and projection lens, the compact optical engine contains only this piece of free form plastic lens, which can be produced by plastic injection molding. Finally a white LED powered LCOS optical engine with a compact size of less than 6.6 cc can be acquired. With the ray tracing simulation result, the light efficiency analysis shows that the output flux is over 8.5 ANSI lumens and the ANSI uniformity of over 80%.

  6. Surgical operation using lighting goggle composed of white LED arrays

    NASA Astrophysics Data System (ADS)

    Shimada, Junichi; Kawakami, Yoichi; Fujita, Shigeo

    2001-12-01

    Everywhere in the world, the highest quality and quantity of lighting is required during the surgical operations. However, the surgical approach has had many types and various angles, common ceiling surgical halogen lighting system cannot provide an adequate amount of beams because the surgeons' heads hinder the illuminations from reaching the operation field. Here, we newly design surgical lighting system composed of white LEDs equipped on both sides of goggles, which controls the lighting beams to the gazing point. With this system, it is just needed for surgeons to wear light plastic goggles with high quality LEDs made by Nichia. In fact, we have succeeded in the first internal shunt operation in the left forearm using the surgical LED lighting system on 11th Sept 2000. The electrical power for the system was supplied from lithium-ion battery for 2 hours. Since the white LEDs used were composed of InGaN-blue-emitters and YAG-yellow-phosphors, the color rendering property was not sufficient in the reddish colors. Therefore, in the next approach, it is very important to develop the spectral distribution of white LED to render inherent color of raw flesh such as skin, blood, fat tissue and internal organs. To improve the color rendering in red colors, some adjustments should be given in the fluorescents layers. Design of goggle is also very important for cutting into the real practical market of white LEDs.

  7. Fully phosphor-converted LEDs with Lumiramic phosphor technology

    NASA Astrophysics Data System (ADS)

    Bechtel, Helmut; Schmidt, Peter J.; Tücks, Andreas; Heidemann, Matthias; Chamberlin, Danielle; Müller-Mach, Regina; Müller, Gerd O.; Shchekin, Oleg

    2010-08-01

    Fully phosphor-converted LEDs (FpcLeds) with saturated emission have been realized in the green and amber spectral region. With the Lumiramic phosphor technology it is possible to achieve high package efficiency with minimum transmission of blue light from the primary LED source. This is done by keeping the scattering properties of the phosphor layer low while the phosphor thickness is chosen to fully convert all blue LED emission. It is shown that this can be done not only for optically isotropic Lumiramic materials like garnets, but also for oxonitridosilicate materials like the green emitting Europium doped SrSi2O2N2, crystallizing in a triclinic lattice with three optical axes. The scattering power of the Lumiramic can be decreased to acceptable levels by increasing the size of the crystallites in the densely sintered ceramics. Light propagation is found to be described well with Mie scattering of mono-sized SrSi2O2N2 spheres with refraction index differing by 0.07 to the refractive index of a SrSi2O2N2 matrix material. Using this technology, the green-yellow gap of visible light emitting LEDs can be bridged and color tunable lamps with the efficiency and flux of today's white phosphor-converted LEDs become feasible.

  8. Optical properties of LEDs with patterned 1D photonic crystal

    NASA Astrophysics Data System (ADS)

    Hronec, P.; Kuzma, A.; Å kriniarová, J.; Kováč, J.; Benčurová, A.; Haščík, Å.; Nemec, P.

    2015-08-01

    In this paper we focus on the application of the one-dimensional photonic crystal (1D PhC) structures on the top of Al0.295Ga0.705As/GaAs multi-quantum well light emitting diode (MQW LED). 1D PhC structures with periods of 600 nm, 700 nm, 800 nm, and 900 nm were fabricated by the E-Beam Direct Write (EBDW) Lithography. Effect of 1D PhC period on the light extraction enhancement was studied. 1D PhC LED radiation profiles were obtained from Near Surface Light Emission Images (NSLEI). Measurements showed the strongest light extraction enhancement using 800 nm period of PhC. Investigation of PhC LED radiation profiles showed strong light decoupling when light reaches PhC structure. Achieved LEE was from 22.6% for 600 nm PhC LED to 47.0% for 800 nm PhC LED. LED with PhC structure at its surface was simulated by FDTD simulation method under excitation of appropriate launch field.

  9. III-nitride monolithic LED covering full RGB color gamut

    NASA Astrophysics Data System (ADS)

    El-Ghoroury, Hussein S.; Chuang, Chih-Li; Kisin, Mikhail V.

    2016-03-01

    We present numerical simulation of III-nitride monolithic multi-color LED covering full red-green-blue (RGB) color gamut. The RGB LED structure was grown at Ostendo Technologies Inc. and has been used in Ostendo proprietary Quantum Photonic Imager (QPI) device. Active region of our RGB LED incorporates specially designed intermediate carrier blocking layers (ICBLs) controlling transport of each type of carriers and subsequent carrier injection redistribution among the optically active quantum wells (QWs) with different emission wavelengths. ICBLs are proved to be essential elements of multi-color LED active region design requiring optimization both in material composition and doping level. Strong interdependence between ICBL parameters and active QW characteristics presents additional challenge to multi-color LED design. Combination of several effects was crucial for adequate simulation of RGB LED color control features. Standard drift-diffusion transport model has been appended with rate equations for dynamic QW-confined carrier populations which appear severely off-balanced from corresponding mobile carrier subsystems. QW overshoot and Auger-assisted QW depopulation were also included into the carrier kinetic model thus enhancing the non-equilibrium character of QW confined populations and supporting the mobile carrier transport across the MQW active region. For device simulation we use COMSOL-based program suit developed at Ostendo Technologies Inc.

  10. Infrared imaging of LED lighting tubes and fluorescent tubes

    NASA Astrophysics Data System (ADS)

    Siikanen, Sami; Kivi, Sini; Kauppinen, Timo; Juuti, Mikko

    2011-05-01

    The low energy efficiency of conventional light sources is mainly caused by generation of waste heat. We used infrared (IR) imaging in order to monitor the heating of both LED tube luminaires and ordinary T8 fluorescent tubes. The IR images showed clearly how the surface temperatures of the fluorescent tube ends quickly rose up to about +50...+70°C, whereas the highest surface temperatures seen on the LED tubes were only about +30...+40°C. The IR images demonstrated how the heat produced by the individual LED chips can be efficiently guided to the supporting structure in order to keep the LED emitters cool and hence maintain efficient operation. The consumed electrical power and produced illuminance were also recorded during 24 hour measurements. In order to assess the total luminous efficacy of the luminaires, separate luminous flux measurements were made in a large integrating sphere. The currently available LED tubes showed efficacies of up to 88 lm/W, whereas a standard "cool white" T8 fluorescent tube produced ca. 75 lm/W. Both lamp types gave ca. 110 - 130 lx right below the ceiling-mounted luminaire, but the LED tubes consume only 40 - 55% of the electric power compared to fluorescent tubes.

  11. Commercial users panel

    NASA Technical Reports Server (NTRS)

    Byrd, Joseph S.; Flatau, Carl; Hodge, David C.; Hollis, Ralph; Leach, Eugene F.; Gilbert, Ray; Cleland, John; Leifer, Larry; Naser, Joseph; Schmuter, Samson D.

    1987-01-01

    The discussions of motives and requirements for telerobotics application demonstrated that, in many cases, lack of progress was a result not of limited opportunities but of inadequate mechanisms and resources for promoting opportunities. Support for this conclusion came from Telerobotics, Inc., one of the few companies devoted primarily to telerobot systems. They have produced units for such diverse applications as nuclear fusion research, particle accelerators, cryogenics, firefighting, marine biology/undersea systems and nuclear mobile robotics. Mr. Flatau offered evidence that telerobotics research is only rarely supported by the private sector and that it often presents a difficult market. Questions on the mechanisms contained within the NASA technology transfer process for promoting commercial opportunities were fielded by Ray Gilbert and Tom Walters. A few points deserve emphasis: (1) NASA/industry technology transfer occurs in both directions and NASA recognizes the opportunity to learn a great deal from industry in the fields of automation and robotics; (2) promotion of technology transfer projects takes a demand side approach, with requests to industry for specific problem identification. NASA then proposes possible solutions; and (3) comittment ofmotivated and technically qualified people on each end of a technology transfer is essential.

  12. A portable time-domain LED fluorimeter for nanosecond fluorescence lifetime measurements

    SciTech Connect

    Wang, Hongtao; Salthouse, Christopher D.; Qi, Ying; Mountziaris, T. J.

    2014-05-15

    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 μM. 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.

  13. The value, solutions, and costs of patterning LED's

    NASA Astrophysics Data System (ADS)

    Watts, Michael P. C.; Zoorob, M.; Lee, T.; McKenzie, J.

    2007-02-01

    The literature on high brightness LED's shows that patterning the top surface of LED's with photonic crystals is being used to create the most intense LED light sources. The best example is that you can now buy projection displays that are illuminated by LED's with Photonic Crystals. The experimental and model data, reviewed in this article, shows that patterning delivers value through improved beam shaping and light extraction using carefully optimized photonic crystals. The data also suggests that in the future, patterning in combination with sub micron device layers and strategically placed mirrors can produce extraction efficiencies of greater than 80%. In addition, patterning can improve current spreading and reduce epitaxy defects. The long term goal is to develop a LED that can be used with minimal additional packaging to focus the light or extract heat. The solution to low cost patterning for Photonic Crystals 100 nm features is to use imprint. The imprint patterning process is implemented in a module that consists of a clean and coat tool, an imprint tool and an etch tool. Cleaning is essential because imprint is a contact technology and particles will lead to process defects and mold damage. There are 2 companies that are developing production tools for LED applications; Molecular Imprints (MII) and Obducat. There are 2 companies that are supporting research tools, and expect to develop production systems in response to customer order, EV Group and Nanonex. The principal difference between imprint suppliers are the different strategies used to conform the mold to the substrate, and the state of system development. To date MII has published the most complete process performance data on an automated production tool. The cost of patterning is less than 0.5 cent per device. First the value of increased LED output will be described, followed by a discussion of the different patterning solutions for improving output, then the different solutions for creating

  14. In vitro inactivation of Enterococcus faecalis with a led device.

    PubMed

    D'Ercole, S; Spoto, G; Trentini, P; Tripodi, D; Petrini, M

    2016-07-01

    Non-coherent light-emitting diodes (LEDs) are effective in a large variety of clinical indications; however, the bactericidal activity of LEDs is unclear, although the effectiveness of such lights is well known. Currently, no studies have examined the effects of NIR-LED on bacteria. The aims of this study were to verify the antibacterial activity of 880-nm LED irradiation on a bacterial suspension of Enterococcus faecalis and to compare it with the actions of sodium hypochlorite (NaOCl) and the concurrent use of both treatments. Before we proceeded with the main experiment, we first performed preliminary tests to evaluate the influence of such parameters as the distance of irradiation, the energy density, the irradiation time and the presence of photosensitizers on the antimicrobial effects of LEDs. After treatment, the colony forming units per milliliter (CFU/mL) was recorded and the data were submitted to ANOVA and Bonferroni post hoc tests at a level of significance of 5%. The results showed that LED irradiation, at the parameters used, is able to significantly decrease E. faecalis viability in vitro. The total inhibition of E. faecalis was obtained throughout concurrent treatment of LED and NaOCl (1%) for 5min. The same antimicrobial activity was confirmed in all of the experiments (p<0.05), but no statistically significant differences were found by varying such parameters as the distance of irradiation (from 0.5mm to 10mm), energy density (from 2.37 to 8.15mJ/s), irradiation time (from 5min to 20min) or by adding toluidine blue O (TBO). PMID:27107704

  15. Fundamentals of Commercial Art. Module 1. Commercial Art. Instructor's Guide.

    ERIC Educational Resources Information Center

    Davis, Diane; Tadrick, Christine

    This module is the first of five in the Commercial Art series. The curriculum guide is designed for competency-based teaching and testing. Within this module on fundamentals of commercial art are six instructional units. A cross-reference table reveals how the instructional components of the module relate to Missouri competencies. Each unit…

  16. Commercial Art I and Commercial Art II: An Instructional Guide.

    ERIC Educational Resources Information Center

    Montgomery County Public Schools, Rockville, MD.

    A teacher's guide for two sequential one-year commercial art courses for high school students is presented. Commercial Art I contains three units: visual communication, product design, and environmental design. Students study visual communication by analyzing advertising techniques, practicing fundamental drawing and layout techniques, creating…

  17. Progress toward achieving high power and high efficiency semipolar LEDs and their characterization

    NASA Astrophysics Data System (ADS)

    Zhong, Hong

    Performance of current commercially available wurtzite nitride based light-emitting diodes (LEDs), grown along the polar (0001) c-plane orientation, is limited by the presence of polarization-related electric fields inside multi-quantum wells (MQWs). The discontinuities in both spontaneous and piezoelectric polarization at the heterointerfaces result in internal electric fields in the quantum wells. These electric fields cause carrier separation [quantum confined Stark effect (QCSE)] and reduce the radiative recombination rate within the quantum wells. One approach to reduce and possibly eliminate the polarization-related effects is to grow III-nitride devices on crystal planes that are inclined with respect to the c-axis, i.e., on semipolar planes. In this dissertation, metalorganic chemical vapor deposition (MOCVD) has been employed for the homoepitaxial growth of GaN based LEDs on semipolar orientations. As a consequence of growing on high-quality bulk GaN substrates, the LEDs have significantly reduced threading dislocation and stacking fault densities, resulting in remarkable improvements in EQE and output power. High efficiency semipolar (1011) violet-blue and blue LEDs have been demonstrated without any intentional effort to enhance the light extraction from those devices. Optimizations of epitaxial structures have led to increased output power and external quantum efficiency. A silicone encapsulated single quantum well blue LED with peak wavelength of 444 nm with output power of 24.3 mW, external quantum efficiency of 43% and luminous efficacy of 75 lm/W (with phosphorescent coating) at 20 mA has been demonstrated. Polarization fields in strained (1011) and (112¯2) InGaN quantum wells have been experimentally determined through bias-dependent optical studies. Our results show that the polarization field flips its direction in semipolar InGaN quantum wells with large inclination angles (i.e. around 60°). This suggests that there exists a polarization

  18. (abstract) Space Science with Commercial Funding

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The world-wide recession, and other factors, have led to reduced or flat budgets in real terms for space agencies around the world. Consequently space science projects and proposals have been under pressure and seemingly will continue to be pressured for some years into the future. A new concept for space science funding is underway at JPL. A partnership has been arranged with a commercial, for-profit, company that proposes to implement a (bandwidth-on-demand) information and telephone system through a network of low earth orbiting satellites (LEO). This network will consist of almost 1000 satellites operating in polar orbit at Ka-band. JPL has negotiated an agreement with this company that each satellite will also carry one or more science instruments for astrophysics, astronomy, and for earth observations. This paper discussed the details of the arrangement and the financial arrangements. It describes the technical parameters, such as the 60 GHz wideband inter-satellite links and the frequency, time, and position control, on which the science is based, and it also discusses the complementarity of this commercially funded space science with conventional space science.

  19. COMMERCIAL SURROGACY: WHAT ROLE FOR LAW IN AUSTRALIA?

    PubMed

    Sifris, Ronli; Ludlow, Karinne; Sifris, Adiva

    2015-12-01

    This editorial begins by illuminating current conversations regarding the regulation of commercial surrogacy in Australia. It defines "commercial surrogacy" and explains the interaction between changes in social attitudes and changes to the law before setting out the current Australian law and practice in this area. An examination of current domestic law and practice reveals that surrogacy legislation in Australia is mired in inconsistencies and a lack of uniformity but that the one key common element is the prohibition of commercial surrogacy. The inability of couples to access commercial surrogacy within Australia has led to offshore reproductive tourism and unpredictable, contradictory decision-making as the Family Court attempts to apply legislation which was never intended to apply in this context. The editorial then turns to consider the international arena, discussing the approach of the Hague Conference on Private International Law before delving into a human rights analysis of commercial surrogacy arrangements. The adoption of a rights-based approach requires an analysis of this vexed issue from the perspective of the child, surrogate and intending parents. While questions surrounding the human rights implications of legalising commercial surrogacy continue to be the subject of passionate debate, the authors believe that the human rights of all parties are best protected through appropriate regulation rather than absolute prohibition. PMID:26939494

  20. From suborbital space tourism to commercial personal spaceflight

    NASA Astrophysics Data System (ADS)

    Peeters, Walter

    2010-06-01

    Excellent essays have been recently published on the profitability and the future of space tourism. This paper is intended to supplement the considerations in this field and emphasizes the further potential evolution of commercial personal spaceflights. Indeed, based upon work done at the International Space University (ISU) the oligopolistic character of suborbital space tourism has been linked to marketing and product life cycle (PLC) considerations and has led to the thesis that space tourism as a profitable sector will require a follow-on strategy. Orbital space tourism, on one hand, could become an extension of the PLC but, on the other hand, it is assumed that point-to-point (P2P) commercial space transport will become the long term sustainable market. Without ignoring technical challenges, this paper will mainly concentrate on marketing and commercial aspects of personal spaceflight.

  1. Thermal simulation of flexible LED package enhanced with copper pillars

    NASA Astrophysics Data System (ADS)

    Yang, Liu; Leung, Stanley Y. Y.; Wong, Cell K. Y.; Yuan, Cadmus A.; Guoqi, Zhang; Fenglian, Sun

    2015-06-01

    Chip on flexible substrate (COF) is a new packaging technology for light emitting diodes (LED). This paper investigated the effect of Cu-pillar in the polyimide (PI) layer on the thermal properties of COF LED packages by finite element analysis. The thermal distribution and thermal resistance were studied in both COF LED packages with and without Cu-pillar. The PI layer showed the highest thermal resistance in the typical package and led to a high chip temperature. With the addition of Cu-pillars, however, the thermal resistance of the PI layer significantly decreased due to the improvement of vertical thermal dissipation under LED chips. Based on the results of simulation and calculation, the relationship between the amount of Cu-pillar and thermal resistance of the COF package has been built. For the packages studied in this research, an 8 × 8 Cu-pillars array was adequate to improve the thermal performance of COF packages. Project supported by the Research and Scientific Foundation of Heilongjiang Education Department (No. 12541112).

  2. Highly Efficient Small Form Factor LED Retrofit Lamp

    SciTech Connect

    Steven Allen; Fred Palmer; Ming Li

    2011-09-11

    This report summarizes work to develop a high efficiency LED-based MR16 lamp downlight at OSRAM SYLVANIA under US Department of Energy contract DE-EE0000611. A new multichip LED package, electronic driver, and reflector optic were developed for these lamps. At steady-state, the lamp luminous flux was 409 lumens (lm), luminous efficacy of 87 lumens per watt (LPW), CRI (Ra) of 87, and R9 of 85 at a correlated color temperature (CCT) of 3285K. The LED alone achieved 120 lumens per watt efficacy and 600 lumen flux output at 25 C. The driver had 90% electrical conversion efficiency while maintaining excellent power quality with power factor >0.90 at a power of only 5 watts. Compared to similar existing MR16 lamps using LED sources, these lamps had much higher efficacy and color quality. The objective of this work was to demonstrate a LED-based MR16 retrofit lamp for replacement of 35W halogen MR16 lamps having (1) luminous flux of 500 lumens, (2) luminous efficacy of 100 lumens per watt, (3) beam angle less than 40{sup o} and center beam candlepower of at least 1000 candelas, and (4) excellent color quality.

  3. Medical lighting composed of LED arrays for surgical operation

    NASA Astrophysics Data System (ADS)

    Shimada, Junichi; Kawakami, Yoichi; Fujita, Shigeo

    2001-05-01

    Everywhere in the world, the highest quality and quantity of lighting is required during the surgical operations. However, the surgical approach has had many types and various angles, common ceiling surgical halogen lighting system cannot provide an adequate amount of beams because the surgeons' heads hinder the illuminations from reaching the operation field. Here, we newly design surgical lighting system composed of white LEDs equipped on both sides of goggles, which controls the lighting beams to the gazing point. With this system, it is just needed for surgeons to wear light plastic goggles with high quality LEDs made by Nichia. In fact, we have succeeded in the first internal shunt operation in the left forearm using the surgical LED lighting system on 11th Sept 2000. The electrical power for the system was supplied from lithium-ion battery for 2 hours. Since the white LEDs used were composed of InGaN- blue-emitters and YAG-yellow-phosphors, the color rendering property was not sufficient in the reddish colors. Therefore, in the next approach, it is very important to develop the spectral distribution of white LED to render inherent color of raw flesh such as skin, blood, fat tissue and internal organs.

  4. Optical design of LED-based automotive tail lamps

    NASA Astrophysics Data System (ADS)

    Domhardt, André; Rohlfing, Udo; Klinger, Karsten; Manz, Karl; Kooß, Dieter; Lemmer, Uli

    2007-09-01

    The application of ultra bright monochromatic and white High-Power-LEDs in the range of automotive lighting systems is now state of the art. These LEDs offer new possibilities in optical design and engineering within different fields of automotive lighting, e.g., tail lamps, signal lamps, headlamps and interior lighting. This contribution describes the process of the optical design of an automotive LED tail lamp based on a practical example. We will elaborate the principal geometric approach, the radiometric conditions and the optical design by using standard and advanced mathematical optimization methods. Special attention will be paid to the following topics: efficient light coupling from the LED into the optical device, adaptation of the illuminance and optimization with respect to the requirements from SAE/ECE regulations. It will be shown that the development of LED-lamps requires the complex interaction of several factors. The challenge for the optical designer is to fulfill the technical demands while also considering the appearance of the final product desired by the customer. Further design specifications emerge from the electrical and thermal layout of the lamp.

  5. Aerial LED signage by use of crossed-mirror array

    NASA Astrophysics Data System (ADS)

    Yamamoto, Hirotsugu; Kujime, Ryousuke; Bando, Hiroki; Suyama, Shiro

    2013-03-01

    3D representation of digital signage improves its significance and rapid notification of important points. Real 3D display techniques such as volumetric 3D displays are effective for use of 3D for public signs because it provides not only binocular disparity but also motion parallax and other cues, which will give 3D impression even people with abnormal binocular vision. Our goal is to realize aerial 3D LED signs. We have specially designed and fabricated a reflective optical device to form an aerial image of LEDs with a wide field angle. The developed reflective optical device composed of crossed-mirror array (CMA). CMA contains dihedral corner reflectors at each aperture. After double reflection, light rays emitted from an LED will converge into the corresponding image point. The depth between LED lamps is represented in the same depth in the floating 3D image. Floating image of LEDs was formed in wide range of incident angle with a peak reflectance at 35 deg. The image size of focused beam (point spread function) agreed to the apparent aperture size.

  6. Blue laser diode (LD) and light emitting diode (LED) applications

    NASA Astrophysics Data System (ADS)

    Bergh, Arpad A.

    2004-09-01

    The family of blue LEDs, edge emitting and surface emitting lasers, enable a number of applications. Blue lasers are used in digital applications such as optical storage in high density DVDs. The resolution of the spot size and hence the storage density is diffraction limited and is inversely proportional to the square of the wavelength of the laser. Other applications include printing, optical scanners, and high-resolution photo-lithography.As light emitters, blue LEDs are used for signaling and in direct view large area emissive displays. They are also making inroads into signage and LCD back-lighting, mobile platforms, and decorative accent lighting in curtains, furniture, etc.Blue LEDs produce white light either with phosphor wavelength converters or in combination with red and green LEDs. The full potential of LED light sources will require three devices to enable complete control over color and intensity.Sensing and medical/bio applications have a major impact on home security, on monitoring the environment, and on health care. New emerging diagnostic and therapeutic applications will improve the quality and reduce the cost of health care.

  7. LED-based endoscopic light source for spectral imaging

    NASA Astrophysics Data System (ADS)

    Browning, Craig M.; Mayes, Samuel; Favreau, Peter; Rich, Thomas C.; Leavesley, Silas J.

    2016-03-01

    Colorectal cancer is the United States 3rd leading cancer in death rates.1 The current screening for colorectal cancer is an endoscopic procedure using white light endoscopy (WLE). There are multiple new methods testing to replace WLE, for example narrow band imaging and autofluorescence imaging.2 However, these methods do not meet the need for a higher specificity or sensitivity. The goal for this project is to modify the presently used endoscope light source to house 16 narrow wavelength LEDs for spectral imaging in real time while increasing sensitivity and specificity. The process to do such was to take an Olympus CLK-4 light source, replace the light and electronics with 16 LEDs and new circuitry. This allows control of the power and intensity of the LEDs. This required a larger enclosure to house a bracket system for the solid light guide (lightpipe), three new circuit boards, a power source and National Instruments hardware/software for computer control. The results were a successfully designed retrofit with all the new features. The LED testing resulted in the ability to control each wavelength's intensity. The measured intensity over the voltage range will provide the information needed to couple the camera for imaging. Overall the project was successful; the modifications to the light source added the controllable LEDs. This brings the research one step closer to the main goal of spectral imaging for early detection of colorectal cancer. Future goals will be to connect the camera and test the imaging process.

  8. LED Lighting: Applying Lessons Learned from the CFL Experience

    SciTech Connect

    McCullough, Jeffrey J.; Gilbride, Theresa L.; Gordon, Kelly L.; Ledbetter, Marc R.; Sandahl, Linda J.; Ton, My K.

    2008-08-20

    Light emitting diode (LED) technology has emerged as an exciting new lighting alternative with the potential for significant energy savings. There is concern, however, that white light LEDs for general illumination could take a long, bumpy course similar to another energy-efficient lighting technology – compact fluorescent lights (CFLs). Recognizing the significant potential energy-efficient lighting has to reduce U.S. energy consumption, Congress mandated in the Energy Policy Act of 2005 that the U.S. Department of Energy (DOE) develop Solid State Lighting (SSL) through a Next Generation Lighting Initiative. DOE’s first step was to analyze the market introduction of compact fluorescent lighting to determine what lessons could be learned to smooth the introduction of SSL in the United States (Sandahl et al. 2006). This paper summarizes applicable lessons learned from the market introduction of CFLs and describe how DOE and others are applying those lessons to speed the development and market introduction of energy-efficient LED lighting for general illumination applications. A description of the current state of LED technology and compares LEDs to incandescent, fluorescent, and halogen lights is also provided.

  9. Non-axisymmetrical freeform design for short LED street lamp

    NASA Astrophysics Data System (ADS)

    Jen, Ching-Hsuan; Chen, Yi-Yung; Whang, Allen Jong-Woei; Lu, Ming-Jun

    2011-10-01

    Based on energy savings trend, LED has been developing as the main force of the future lighting, especially the road lighting. For controlling the intensity distribution of LED, the concept of freeform design has been proposed in many articles with transmission or reflection components but mainly focus on axial symmetrical types or dual axial symmetrical types. We, in this paper, design a non-axisymmetrical freeform system applying in a short LED street lamp whose dimension is 10cm (W) x 10cm (L) x 7cm (H) that has an advantage, easy maintaining. For coordinate transformation and simplifying the non- axisymmetrical system, we create two virtual surfaces and design the slope of each discrete point on the freeform surface to control the light path between the two virtual surfaces and avoid the total internal reflection. The short street lamp has four LEDs to light 3m square and each LED light a triangle area. According to the simulation results, the uniformity of illumination is 1:3 and the optical efficiency is more than 80% that meet the legal requirements of street lamp. In short, to reduce manufacturing and maintenance costs, the proposed design is appropriate to use in the actual lighting on the road and to replace the traditional street lamps.

  10. Commercial Optics for Space Surveillance and Astronomy

    NASA Astrophysics Data System (ADS)

    Ackermann, M.; Kopit, E.; McGraw, J.; Zimmer, P.

    Since the first days of the space program, there have been both amateur and government satellite watchers. Large, expensive government systems with custom optics are still the most capable, but with modern sensors and high speed computers, amateur trackers are easily pushing the limits of what government systems achieved only a decade ago. A very recent trend in the space world is the emergence of commercial space operations centers. Once the exclusive purview of governments, corporations are now providing orbital environment awareness services to the operators of commercial satellites. The requirement for synoptic satellite observations has led to corporations developing world-wide observing networks. A problem facing both amateur and corporate observers is the limited availability of suitable optical systems. Most observing efforts rely on long focus (f/8 or greater) optical systems with focal reducers, and a somewhat limited field of view. Often, the cameras in use are not ideally matched to the optical system. While there are a few exceptions, the choices are not many. Celestron recently introduced the C-11 RASA optical system, with an 11-inch aperture and an f/2.2 focal ratio. This optical system is designed for dedicated imaging and is ideally suited for both wide-field astronomy and the detection and tracking of satellites. The larger C-14 RASA, to be introduced later this year, was specifically designed for wide-field imaging with large commercial CCDs. It offers greater sensitivity and a wider field of view than the smaller C-11 RASA and should prove to be the instrument of choice for both amateur and corporate satellite observers. We present data from satellite observations with a production model C-11 RASA and estimated performance for the new C-14 RASA.

  11. Addendum to the corrective action plan for Underground Storage Tanks 1219-U, 1222-U, 2082-U, 2068-U at the Rust Garage Facility, Buildings 9720-15 and 9754-1: Oak Ridge Y-12 Plant, Oak Ridge, Tennessee, Facility ID {number_sign}0-010117

    SciTech Connect

    Not Available

    1994-01-01

    This document represents an addendum to the Corrective Action Plan (CAP) for underground storage tanks 1219-U, 2082-U, and 2068-U located at Buildings 9720-15 and 9754-1, Oak Ridge Y-12 Plant, Oak Ridge, TN. The site of the four underground storage tanks is commonly referred to as the Rust Garage Facility. The original CAP was submitted to the Tennessee Department of Environment and Conservation (TDEC) for review in May 1992. During the time period after submission of the original CAP for the Rust Garage Facility, Y-12 Plant Underground Storage Tank (UST) Program personnel continued to evaluate improvements that would optimize resources and expedite the activities schedule presented in the original CAP. Based on these determinations, several revisions to the original corrective action process options for remediation of contaminated soils are proposed. The revised approach will involve excavation of the soils from the impacted areas, on-site thermal desorption of soil contaminants, and final disposition of the treated soils by backfilling into the subject site excavations. Based on evaluation of the corrective actions with regard to groundwater, remediation of groundwater under the Y-12 Plant CERCLA Program is proposed for the facility.

  12. Development of a High Irradiance LED Configuration for Small Field of View Motion Estimation of Fertilizer Particles

    PubMed Central

    Cool, Simon; Pieters, Jan G.; Mertens, Koen C.; Mora, Sergio; Cointault, Frédéric; Dubois, Julien; van de Gucht, Tim; Vangeyte, Jürgen

    2015-01-01

    Better characterization of the fertilizer spreading process, especially the fertilizer pattern distribution on the ground, requires an accurate measurement of individual particle properties and dynamics. Both 2D and 3D high speed imaging techniques have been developed for this purpose. To maximize the accuracy of the predictions, a specific illumination level is required. This paper describes the development of a high irradiance LED system for high speed motion estimation of fertilizer particles. A spectral sensitivity factor was used to select the optimal LED in relation to the used camera from a range of commercially available high power LEDs. A multiple objective genetic algorithm was used to find the optimal configuration of LEDs resulting in the most homogeneous irradiance in the target area. Simulations were carried out for different lenses and number of LEDs. The chosen configuration resulted in an average irradiance level of 452 W/m2 with coefficient of variation less than 2%. The algorithm proved superior and more flexible to other approaches reported in the literature and can be used for various other applications. PMID:26569261

  13. Development of a High Irradiance LED Configuration for Small Field of View Motion Estimation of Fertilizer Particles.

    PubMed

    Cool, Simon; Pieters, Jan G; Mertens, Koen C; Mora, Sergio; Cointault, Frédéric; Dubois, Julien; van de Gucht, Tim; Vangeyte, Jürgen

    2015-01-01

    Better characterization of the fertilizer spreading process, especially the fertilizer pattern distribution on the ground, requires an accurate measurement of individual particle properties and dynamics. Both 2D and 3D high speed imaging techniques have been developed for this purpose. To maximize the accuracy of the predictions, a specific illumination level is required. This paper describes the development of a high irradiance LED system for high speed motion estimation of fertilizer particles. A spectral sensitivity factor was used to select the optimal LED in relation to the used camera from a range of commercially available high power LEDs. A multiple objective genetic algorithm was used to find the optimal configuration of LEDs resulting in the most homogeneous irradiance in the target area. Simulations were carried out for different lenses and number of LEDs. The chosen configuration resulted in an average irradiance level of 452 W/m² with coefficient of variation less than 2%. The algorithm proved superior and more flexible to other approaches reported in the literature and can be used for various other applications. PMID:26569261

  14. Thermal and optical design analyses, optimizations, and experimental verification for a novel glare-free LED lamp for household applications.

    PubMed

    Khan, M Nisa

    2015-07-20

    Light-emitting diode (LED) technologies are undergoing very fast developments to enable household lamp products with improved energy efficiency and lighting properties at lower cost. Although many LED replacement lamps are claimed to provide similar or better lighting quality at lower electrical wattage compared with general-purpose incumbent lamps, certain lighting characteristics important to human vision are neglected in this comparison, which include glare-free illumination and omnidirectional or sufficiently broad light distribution with adequate homogeneity. In this paper, we comprehensively investigate the thermal and lighting performance and trade-offs for several commercial LED replacement lamps for the most popular Edison incandescent bulb. We present simulations and analyses for thermal and optical performance trade-offs for various LED lamps at the chip and module granularity levels. In addition, we present a novel, glare-free, and production-friendly LED lamp design optimized to produce very desirable light distribution properties as demonstrated by our simulation results, some of which are verified by experiments. PMID:26367844

  15. 150 Passenger Commercial Aircraft

    NASA Technical Reports Server (NTRS)

    Bucovsky, Adrian; Romli, Fairuz I.; Rupp, Jessica

    2002-01-01

    It has been projected that the need for a short-range mid-sized, aircraft is increasing. The future strategy to decrease long-haul flights will increase the demand for short-haul flights. Since passengers prefer to meet their destinations quickly, airlines will increase the frequency of flights, which will reduce the passenger load on the aircraft. If a point-to-point flight is not possible, passengers will prefer only a one-stop short connecting flight to their final destination. A 150-passenger aircraft is an ideal vehicle for these situations. It is mid-sized aircraft and has a range of 3000 nautical miles. This type of aircraft would market U.S. domestic flights or inter-European flight routes. The objective of the design of the 150-passenger aircraft is to minimize fuel consumption. The configuration of the aircraft must be optimized. This aircraft must meet CO2 and NOx emissions standards with minimal acquisition price and operating costs. This report contains all the work that has been performed for the completion of the design of a 150 passenger commercial aircraft. The methodology used is the Technology Identification, Evaluation, and Selection (TIES) developed at Georgia Tech Aerospace Systems Design laboratory (ASDL). This is an eight-step conceptual design process to evaluate the probability of meeting the design constraints. This methodology also allows for the evaluation of new technologies to be implemented into the design. The TIES process begins with defining the problem with a need established and a market targeted. With the customer requirements set and the target values established, a baseline concept is created. Next, the design space is explored to determine the feasibility and viability of the baseline aircraft configuration. If the design is neither feasible nor viable, new technologies can be implemented to open up the feasible design space and allow for a plausible solution. After the new technologies are identified, they must be evaluated

  16. Commercial researcher perspective

    NASA Astrophysics Data System (ADS)

    Delucas, Larry

    Protein crystallography--a research tool used to study the structure of the complex building blocks of living systems--has a lot to gain from space-based research. In order to know how a protein works in the human body, researchers must understand its molecular structure. Researchers have identified 150,000 different proteins in the body, but they now know the structure of less than a third of them. The only viable technique for analyzing the structure of these proteins is x-ray diffraction of the proteins in their crystal form. The better the quality of a protein crystal, the more useful it is to researchers who are trying to delineate its structure. The microgravity environment of space allows protein crystals to grow nearly undisturbed by convection and other gravity-driven forces that cause flaws to form in them on the ground. In space, lack of convection enables protein crystals to grow more slowly than they do on Earth, and the slower a protein crystal grows, the fewer flaws it will have. Protein crystal growth experiments have already flown on 14 Space Shuttle missions. This year's USML-1 Spacelab mission included protein crystal growth experiments conducted for commercial researchers. The results of protein crystal experiments flown thus far have been larger crystals with more uniform morphologies. The Center for Macromolecular Crystallography (A NASA-cosponsored CCDS) currently builds flight hardware to meet researchers' needs and handles sample loading and retrieval for flight experiments. Protein crystallography enables 'rational drug design': the development of drugs that bind only with the target protein and, hence, do not cause side effects. For example, pharmaceutical companies presently are interested in developing drugs that can inhibit purine nucleoside phosphorylase (PNP), a protein that plays a role in auto-immune diseases. To continue these kinds of investigations, researchers need a constant supply of protein crystals that are as free of flaws

  17. Commercial researcher perspective

    NASA Technical Reports Server (NTRS)

    Delucas, Larry

    1992-01-01

    Protein crystallography--a research tool used to study the structure of the complex building blocks of living systems--has a lot to gain from space-based research. In order to know how a protein works in the human body, researchers must understand its molecular structure. Researchers have identified 150,000 different proteins in the body, but they now know the structure of less than a third of them. The only viable technique for analyzing the structure of these proteins is x-ray diffraction of the proteins in their crystal form. The better the quality of a protein crystal, the more useful it is to researchers who are trying to delineate its structure. The microgravity environment of space allows protein crystals to grow nearly undisturbed by convection and other gravity-driven forces that cause flaws to form in them on the ground. In space, lack of convection enables protein crystals to grow more slowly than they do on Earth, and the slower a protein crystal grows, the fewer flaws it will have. Protein crystal growth experiments have already flown on 14 Space Shuttle missions. This year's USML-1 Spacelab mission included protein crystal growth experiments conducted for commercial researchers. The results of protein crystal experiments flown thus far have been larger crystals with more uniform morphologies. The Center for Macromolecular Crystallography (A NASA-cosponsored CCDS) currently builds flight hardware to meet researchers' needs and handles sample loading and retrieval for flight experiments. Protein crystallography enables 'rational drug design': the development of drugs that bind only with the target protein and, hence, do not cause side effects. For example, pharmaceutical companies presently are interested in developing drugs that can inhibit purine nucleoside phosphorylase (PNP), a protein that plays a role in auto-immune diseases. To continue these kinds of investigations, researchers need a constant supply of protein crystals that are as free of flaws

  18. Space Station commercial user development

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The commercial utilization of the space station is investigated. The interest of nonaerospace firms in the use of the space station is determined. The user requirements are compared to the space station's capabilities and a feasibility analysis of a commercial firm acting as an intermediary between NASA and the private sector to reduce costs is presented.

  19. Teaching Commercial German Through Advertisements.

    ERIC Educational Resources Information Center

    Heyer, Elfriede A.

    Advertisements can be used in many ways to facilitate the teaching of a commercial language. If reproduced as slides or other visual aids, they serve as a visual warm-up exercise for each class period, either reinforcing previously discussed topics or introducing new ones. Catchy headlines in commercials promote rapid expansion of vocabulary and…

  20. Lessons learned: The commercialization process

    SciTech Connect

    Padilla, B.A.; Gritzo, R.E.; Garcia, J.J.

    1996-03-01

    One successful component of a commercialization strategy includes the implementation of an industrial outreach workshop. This workshop is designed to select an industrial partner with the skills necessary to successfully commercialize a federally-funded, laboratory developed technology. These workshops provide efficiency and effectiveness and, in addition, ensure that all prospective partners receive equal access to the same quality and quantity of information.

  1. Commercialization of MHD power technology

    SciTech Connect

    Aleman, D.J.; Jensen, A.D.; Probert, P.B.

    1984-08-01

    This paper presents an approach to the commercialization of Magnetohydrodynamics (MHD) technology from the perspective of an equipment manufacturer. It discusses and recommends actions to be taken in solving technical problems and mitigating risk for the first commercial MHD power plant.

  2. Analysis of Commercial Contract Training.

    ERIC Educational Resources Information Center

    Copeland, D. Robert; And Others

    The report describes the Phase I findings of a two-phase study to determine the applications of commercial contract training to the Navy Training System. The objective of the study is to determine if commercial sources would be cost and training effective alternatives for current and peak Navy skill training requirements. The study was conducted…

  3. Novel chip coating approaches to improve white LED technology

    NASA Astrophysics Data System (ADS)

    Hartmann, Paul; Schweighart, Marko; Sommer, Christian; Wenzl, Franz-P.; Zinterl, Ernst; Hoschopf, Hans; Pachler, Peter; Tasch, Stefan

    2008-02-01

    Key market requirements for white LEDs, especially in the general lighting and automotive headlamp segments call for improved concepts and performance of white LEDs based on phosphor conversion. Major challenges are small emission areas, highest possible intensities, long-term color stability, and spatial homogeneity of color coordinates. On the other hand, the increasingly high radiation power of the blue LEDs poses problems for all involved materials. Various thick film coating technologies are widely used for applying the color conversion layer to the semiconductor chip. We present novel concepts based on Silicate phosphors with high performance in terms of spatial homogeneity of the emission and variability of the color temperature. Numerical calculation of the optical properties with the help of state-of-the-art simulation tools was used as a basis for the practical optimization of the layer geometries.

  4. Tests gauge LED sensors for fuel-dye measurements

    SciTech Connect

    Ozanich, Richard M.; Lucke, Richard B.; Melville, Angela M.; Wright, Bob W.

    2009-10-19

    The goal of this work was to develop a low cost, robust sensor to allow direct measurement of Solvent Red 164 dye concentration in off-road fuel at refineries and fuel terminals. Optical absorption sensors based on light emitting diodes (LEDs) are rugged, low-cost, have low power consumption, and can be designed to be intrinsically safe.LED-based systems have been used in a variety of chemical detection applications including heavy metals, pH, CO2, and O2. The approach for this work was to develop a sensor that could be mounted on a pipeline sight glass, precluding the need for direct contact of the sensor with the fuel. Below is described the design and testing of three different LED/photodiode sensors utilizing reflectance spectrometry for the measurement of dye concentration.

  5. A novel temperature compensated operation scheme for trichromatic LED backlights

    NASA Astrophysics Data System (ADS)

    Lee, Dong-Woo; Kim, Jin-Ha; Park, Moo-Youn; Kim, Hee-Dong; Park, Jae-Kyuk; Hwang, Soo-Ryong; Cho, Sung-Min

    2007-02-01

    Trichromatic LED backlights render higher color gamut and panel transmittance to liquid crystal displays (LCDs) than yellow phosphor-converted white LED backlights can possibly do at their best. In realization, however, several technical challenges arise, such as colour shift due to the ambient temperature change, decrease in brightness at elevated temperature, an enlarged dead zone for colour mixing, minimizing the total number of chips and so on. In this work, we designed and demonstrated a low-cost driving circuit that stabilizes brightness and colour coordinates of trichromatic LED backlights using a thermistor as a temperature compensating element. By applying the temperature compensation, the amounts of the brightness and colour shift were reduced to 54% and 51% of the uncompensated cases, respectively.

  6. Packaging efficiency analysis of phosphor-converted white LEDs

    NASA Astrophysics Data System (ADS)

    Sun, Ching-Cherng; Chang, Yu-Yu; Chen, Cheng-Chien; Chen, Ching-Yi; Yang, Tsung-Hsun

    2014-09-01

    In this paper, we present our study in packaging efficiency for phosphor-converted white LED (pcW-LED). Then the limit of luminous efficacy of a pcW-LED in different types of packaging is estimated. In the calculation, the EQE of the blue die is assumed 81% and the Stokes loss is counted, we obtain the limit of luminous efficacy, which reaches 300 lm/W, when the color appearance is green-white and the corresponding CCT is between 4000K to 5000K. More consideration for practical limit take consideration of phosphor quantum loss and geometry loss, and the limit of luminous for CRI around 60 is around 240 lm/W, and for CRI larger than 80 is around 175 lm/W.

  7. Energy Efficient White LEDs for Sustainable Solid—State Lighting

    NASA Astrophysics Data System (ADS)

    DenBaars, Steve

    2008-09-01

    The R&D—level white—LED single—lamp luminous efficacy has reached levels as high as 152 lumens/watt at low currents, which greatly exceeds the bare—bulb incandescent lamp efficacy of 17 lumens/watt. Commercial—based white LED lamp fixtures are typically much lower, in the region of 64 lm/W, due to several issues associated with scaling up to higher currents, heat, and optical losses. These issues will be solved by employing higher light extraction, better optical designs, new chip designs, and better heat sinking. The long lifetime of LEDs (100,000 hours) and their higher efficiencies could lead to considerable maintenance and energy—saving benefits for consumers.

  8. Philips' 2nd generation Novallure LED candle lamp

    NASA Astrophysics Data System (ADS)

    Li, Yun; Pei, Zhigang; Yuan, Chuan; Jiang, Tan; Lu, Zhengsong; Wang, Yuqian; Duan, Xiaoqing; Xiong, Yan; Zhong, Hong; Liu, Ye

    2010-08-01

    Finding an energy efficient replacement of incandescent candle lamp has been a technical challenge. Compact fluorescent lamps, for example, can be miniaturized to fit the form factor of a candle lamp but they fail to reproduce its "sparkle" effect. Empowered by solid state lighting technology along with original optical design, Philips has successfully developed LED-powered candle lamps "Novallure" with great energy savings (2W power consumption with lumen output of 55 lumen) and the "butterfly" radiation pattern that mimics the sparkle effect from an incandescent candle lamp. With new high performance LED packages, novel under-cut prismatic optics and state-of-the-art electronic driver solution and thermal solution, we have developed a 2nd generation Novallure with breakthrough performance: a dimmable 2700K 136 lumen LED candle lamp with CRI 90.

  9. LED-based digital hologram reconstruction by compressive sensing

    NASA Astrophysics Data System (ADS)

    Weng, Jiawen; Yang, Chuping; Qin, Yi; Li, Hai

    2015-10-01

    LED-based digital hologram, considered as low-coherence digital hologram, is confined to in-line holography because the interference fringes could be observed only when the angle between the object and reference wave is small enough. So, phase-shifting technique is usually employed. But it is not fit for dynamic analysis for demanding more than one hologram. A numerical reconstruction method based on compressive sensing theory for single LED-based digital hologram is proposed to achieve dynamic analysis. By this method, the out-of-focus twin image and the coherent noise can be inhibited to some extent. The theory is presented in detail, and experimental result on LED-based digital holography with USAF pattern as test target, is performed to demonstrate the feasibility and validity of the method.

  10. Developing a nurse-led clinic using transformational leadership.

    PubMed

    Gousy, Mamood; Green, Kim

    2015-03-25

    Nurses are at the forefront of implementing and managing change, given constantly changing healthcare services and the increase in demand for health care. Therefore, it is important to identify the best style of leadership to engage nurses in implementing service-led improvements. This article explores the effects of transformational leadership in bringing about service-led improvements in health care, using the example of setting up a nurse-led acupuncture clinic to optimise the care of patients with chronic pain. Transformational leadership was used throughout the project - from the initial local planning, training and development, through to liaising with the appropriate staff and deciding on an evaluation strategy. Transformational leadership proved to be an effective way to engage and empower nurses and other members of the chronic pain team to enable them to achieve the project aims. PMID:25804177

  11. NASA's approach to space commercialization

    NASA Technical Reports Server (NTRS)

    Gillam, Isaac T., IV

    1986-01-01

    The NASA Office of Commercial Programs fosters private participation in commercially oriented space projects. Five Centers for the Commercial Development of Space encourage new ideas and perform research which may yield commercial processes and products for space ventures. Joint agreements allow companies who present ideas to NASA and provide flight hardware access to a free launch and return from orbit. The experimenters furnish NASA with sufficient data to demonstrate the significance of the results. Ground-based tests are arranged for smaller companies to test the feasibility of concepts before committing to the costs of developing hardware. Joint studies of mutual interest are performed by NASA and private sector researchers, and two companies have signed agreements for a series of flights in which launch costs are stretched out to meet projected income. Although Shuttle flights went on hold following the Challenger disaster, extensive work continues on the preparation of commercial research payloads that will fly when Shuttle flights resume.

  12. Peer-Led Team Learning Helps Minority Students Succeed

    PubMed Central

    Snyder, Julia J.; Sloane, Jeremy D.; Dunk, Ryan D. P.; Wiles, Jason R.

    2016-01-01

    Active learning methods have been shown to be superior to traditional lecture in terms of student achievement, and our findings on the use of Peer-Led Team Learning (PLTL) concur. Students in our introductory biology course performed significantly better if they engaged in PLTL. There was also a drastic reduction in the failure rate for underrepresented minority (URM) students with PLTL, which further resulted in closing the achievement gap between URM and non-URM students. With such compelling findings, we strongly encourage the adoption of Peer-Led Team Learning in undergraduate Science, Technology, Engineering, and Mathematics (STEM) courses. PMID:26959826

  13. LED phototherapy system in skin treatment and detecting

    NASA Astrophysics Data System (ADS)

    Chen, Hsi-Chao; Wu, Jih-Huah; Lin, Ching-Huang; Ma, Shih-Hsin

    2010-08-01

    In this research, a new module of skin treatment has been proposed. The 40 pieces of red and 36 pieces of yellow LEDs are utilized to be the light sources in treatment the cracks and corrosions on skin, and the 4 pieces of white light LEDs are applied in lighting on skin. In addition, the image of skin could be obtained by a CCD webcam, and the skin inspection will be determined by number of pores in images. Finally, the good experimental results have been obtained in human body.

  14. LED and Semiconductor Photo-effects on Living Things

    NASA Astrophysics Data System (ADS)

    Fujiyasu, Hiroshi; Ishigaki, Takemitsu; Fujiyasu, Kentarou; Ujihara, Shirou; Watanabe, Naoharu; Sunayama, Shunji; Ikoma, Shuuji

    We have studied LED irradiation effects on plants and animals in the visible to UV region of light from GaN LEDs. The results are as follows. Blue light considers to be effective for pearl cultivation or for attraction of small fishes living in near the surface of sea such as Pompano or Sardine, white light radiation is effective for cultivation of botanical plankton for shells. Other experiments of UV light irradiation attracting effect on baby sea turtle and the germination UV effect of mushroom, green light weight enhance effect on baby pigs, light vernalization effect of vegitable and Ge far infrared therapic effect on human body are also given.

  15. Peer-Led Team Learning Helps Minority Students Succeed.

    PubMed

    Snyder, Julia J; Sloane, Jeremy D; Dunk, Ryan D P; Wiles, Jason R

    2016-03-01

    Active learning methods have been shown to be superior to traditional lecture in terms of student achievement, and our findings on the use of Peer-Led Team Learning (PLTL) concur. Students in our introductory biology course performed significantly better if they engaged in PLTL. There was also a drastic reduction in the failure rate for underrepresented minority (URM) students with PLTL, which further resulted in closing the achievement gap between URM and non-URM students. With such compelling findings, we strongly encourage the adoption of Peer-Led Team Learning in undergraduate Science, Technology, Engineering, and Mathematics (STEM) courses. PMID:26959826

  16. Controlling Cost Growth in PI-led Missions

    NASA Astrophysics Data System (ADS)

    Harrison, Fiona

    2014-08-01

    While the cost and schedule performance of PI-led competed missions is better than that of strategic missions, the majority of PI-led missions have experienced increases relative to their initial proposed cost. I will review the performance of competed missions, comparing them to flagship observatories. I will describe in general reasons for cost growth starting from assumptions made at the proposal stage to challenges with technology development, technical implementation and management. I will also describe strategies for effective implementation that can be used to manage cost growth.

  17. Modulation selection for visible light communications using lighting LEDs

    NASA Astrophysics Data System (ADS)

    Siuzdak, Jerzy

    2015-09-01

    The paper analyzes suitability of various spectrally efficient modulations (PAM, CAP, OFDM/DMT) in a VLC system using lighting LEDs as a transmitter. Although under ideal conditions all modulation have similar efficiency i.e. they produce similar throughputs with a given BER, their practical performances are different. For example, the level of nonlinear distortions generated by each modulation is the least for PAM and by far the greatest for OFDM/DMT locating CAP in the middle. The suitability of various OFDM/DMT variants in a VLC LED link was also analyzed proving that the asymmetrically clipped (ACO) OFDM has a worse performance as compared with DC biased (DCO) OFDM.

  18. Life-Cycle Assessment of Energy and Environmental Impacts of LED Lighting Products, Part 3: LED Environmental Testing

    SciTech Connect

    Tuenge, Jason R.; Hollomon, Brad; Dillon, Heather E.; Snowden-Swan, Lesley J.

    2013-03-01

    This report covers the third part of a larger U.S. Department of Energy (DOE) project to assess the life-cycle environmental and resource impacts in the manufacturing, transport, use, and disposal of light-emitting diode (LED) lighting products in relation to incumbent lighting technologies. All three reports are available on the DOE website (www.ssl.energy.gov/tech_reports.html). • Part 1: Review of the Life-Cycle Energy Consumption of Incandescent, Compact Fluorescent and LED Lamps; • Part 2: LED Manufacturing and Performance; • Part 3: LED Environmental Testing. Parts 1 and 2 were published in February and June 2012, respectively. The Part 1 report included a summary of the life-cycle assessment (LCA) process and methodology, provided a literature review of more than 25 existing LCA studies of various lamp types, and performed a meta-analysis comparing LED lamps with incandescent and compact fluorescent lamps (CFLs). Drawing from the Part 1 findings, Part 2 performed a more detailed assessment of the LED manufacturing process and used these findings to provide a comparative LCA taking into consideration a wider range of environmental impacts. Both reports concluded that the life-cycle environmental impact of a given lamp is dominated by the energy used during lamp operation—the upstream generation of electricity drives the total environmental footprint of the product. However, a more detailed understanding of end-of-life disposal considerations for LED products has become increasingly important as their installation base has grown. The Part 3 study (reported herein) was undertaken to augment the LCA findings with chemical analysis of a variety of LED, CFL, and incandescent lamps using standard testing procedures. A total of 22 samples, representing 11 different models, were tested to determine whether any of 17 elements were present at levels exceeding California or Federal regulatory thresholds for hazardous waste. Key findings include: • The selected

  19. Effects of LED lighting during incubation on layer and broiler hatchability, chick quality, stress susceptibility and post-hatch growth.

    PubMed

    Huth, Jesse C; Archer, Gregory S

    2015-12-01

    Providing light during incubation has been shown to affect hatchability, but the use of LED lights has not been evaluated. This experiment evaluated the effects of LED lighting during embryogenesis on White Leghorn and commercial broiler eggs. To determine this, two experiments were conducted, the first using White Leghorn eggs (N=3456) and the second using commercial broiler eggs (N=3456) where eggs were incubated 12 h of light and 12 h of darkness (LED) or complete darkness (DARK); the light level was 250 lux. Hatchability, embryo mortality, and chick quality were measured in both studies, and a subset of one of the broiler egg trials were grown out to investigate fear and stress parameters. There was no effect (P>0.05) on hatchability of layer eggs; however, there was a difference (P=0.02) observed in chick quality, with the LED group having more chicks (75.34%) with no defects than the DARK group (56.53%). Broiler eggs exposed to LED light showed an increase in hatchability (90.12%, P=0.03) and an increase in no-defect chick percentage (86.12%, P=0.04) at hatch compared to the DARK chicks (85.76% and 69.43%, respectively). Differences were observed between treatments during the 14 d grow-out. The LED birds had lower (P<0.05) physical asymmetry (0.90±0.05 mm) and heterophil/lymphocyte ratios (0.279±0.021), indicating that they were less susceptible to stress than the DARK birds (1.16±0.07 mm and 0.347±0.021, respectively). There was no difference (P>0.05) observed between treatments in growth, FCR, or fear measures at 14 d. These results indicate that providing LED light during incubation can improve chick quality in both white layer and broiler eggs; however, it only appears to improve hatchability in broilers, which could be related to shell pigmentation. It was also demonstrated that providing LED light during incubation can reduce the stress susceptibility of broilers post-hatch. Utilizing light during incubation may be useful tool for the poultry

  20. Trace analysis of oil-in-water by using visible LED and metal waveguide capillary.

    PubMed

    Bai, Min; Huang, Hui; Yu, Yan; Hao, Jian; Zhang, Ji; Fan, Jianchao; Yan, Jun

    2016-06-27

    Trace analysis of oil-in-water (O/W) has wide applications in life science, industry and environmental monitoring (such as oil spilling). In this paper, with the aid of surfactant, diesel was dispersed in water as O/W emulsion, which can be detected by using visible LED and metal-waveguide-capillary (MWC). Due to the enhancement of optical-path and related light-droplet interaction in MWC, detecting diesel of a concentration as low as 2.14 ng/ml was realized with a 7cm long MWC. The detection limit was improved 125 fold compared with that of commercial spectrophotometer with 1 cm-cuvette. The detecting system features compact, low cost and high sensitivity. PMID:27410606