WorldWideScience

Sample records for technology evolution led

  1. Phosphors and PDP, LED Technology

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Phosphors for PDP has good prospect for the largepotential of PDP industry. LED technology brings new marketto be developed. Developing phosphors for white LED withhigh efficiency and low light attenuation is an urgent work todo. Application of phosphors in color LED is in initial stage.1. Good Prospect of Phosphors for PDPColor PDP is widely used today. Three-prime-colorphosphor excited by VUV is the key material for color PDP.This makes research on three-prime-color phosphor for colorPDP important. Follow...

  2. Next generation DNA led technologies

    CERN Document Server

    Jyothsna, G; Kashyap, Amita

    2016-01-01

    This brief highlights advances in DNA technologies and their wider applications. DNA is the source of life and has been studied since a generation, but very little is known as yet. Several sophisticated technologies of the current era have laid their foundations on the principle of DNA based mechanisms. DNA based technologies are bringing a new revolution of Advanced Science and Technology. Forensic Investigation, Medical Diagnosis, Paternity Disputes, Individual Identity, Health insurance, Motor Insurance have incorporated the DNA testing and profiling technologies for settling the issues.

  3. White LED visible light communication technology research

    Science.gov (United States)

    Yang, Chao

    2017-03-01

    Visible light communication is a new type of wireless optical communication technology. White LED to the success of development, the LED lighting technology is facing a new revolution. Because the LED has high sensitivity, modulation, the advantages of good performance, large transmission power, can make it in light transmission light signal at the same time. Use white LED light-emitting characteristics, on the modulation signals to the visible light transmission, can constitute a LED visible light communication system. We built a small visible optical communication system. The system composition and structure has certain value in the field of practical application, and we also research the key technology of transmitters and receivers, the key problem has been resolved. By studying on the optical and LED the characteristics of a high speed modulation driving circuit and a high sensitive receiving circuit was designed. And information transmission through the single chip microcomputer test, a preliminary verification has realized the data transmission function.

  4. Silicon LEDs in FinFET technology

    NARCIS (Netherlands)

    Piccolo, G.; Kuindersma, P.I.; Ragnarsson, L-A.; Hueting, R.J.E.; Collaert, N.; Schmitz, J.

    2014-01-01

    We present what to our best knowledge is the first forward operating silicon light-emitting diode (LED) in fin-FET technology. The results show near-infrared (NIR) emission around 1100 nm caused by band-to-band light emission in the silicon which is uniformly distributed across the lowly doped activ

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

    Science.gov (United States)

    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…

  6. Sustainable LED Fluorescent Light Replacement Technology

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2011-09-30

    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 comparable

  7. Markets and technology needs for UHB-LEDs

    Science.gov (United States)

    Roussel, Philippe

    2007-09-01

    With an annual volume of more than 5 million units of 2" equivalent substrates, GaN-based LED is the main eater of nitride materials targeting a 3.5B market at devices level. The next big challenge for LED business is to take market shares over the general lighting industry and dollar per lumen (/lm) ratio is the key parameter. Numerous technological improvements are under investigation: - At die level, photonic crystals and surface texturing technologies are jointly developed to increase the light extraction. External Quantum Efficiency EQE has now reached > 75% at R&D level. - At material level, there is a rapid emergence of new substrates for GaN epitaxy and composite substrates in 6" diameter. That is opening new doors to higher LED luminous efficiency and cost reduction toward the gigantic SSL general illumination business.

  8. Novel chip coating approaches to improve white LED technology

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Radovan Stojanovic

    2013-01-01

    Full Text Available 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.

  10. CVC Funding and Technological Evolution

    DEFF Research Database (Denmark)

    Corredoira, Rafael; Di Lorenzo, Francesco

    How the interaction of incumbents and new ventures drives economic growth has been at the center of attention since early Schumpeter’s work. In this paper, we focus on whether corporate investment moves the technological position of the new venture toward the technological frontier or not...... on the CVC investment process, our regression results show that the power of the CVC over the syndicate is associated to new venture’s inventions with more influence on the evolution of technology. In addition, the effect decreases when power is derived from older investments. This suggests a “honeymoon...... effect,” where the transfer of technological capabilities and support for the new venture wears out as time goes by. Our graphical analysis also found evidence of transfer of technological capabilities from the corporation to the new venture. This transfer is mostly associated to CVC power over...

  11. Progress in LED technology for solid-state lighting

    Science.gov (United States)

    Bhardwaj, Jy; Guth, Greg; Cesaratto, John M.; Shchekin, Oleg B.; Soer, Wouter A.; Götz, Werner; Bonné, Ron; Song, Zhihua F.; den Breejen, Jeroen

    2017-02-01

    As solid-state lighting adoption moves from bulb socket replacement to lighting system engineering, luminaire manufacturers are beginning to actualize far greater cost savings through luminaire optimization rather than the simplistic process of component cost pareto management. Indeed, there are an increasing number of applications in which we see major shifts in the value chain in terms of increasing the L1 (LED) and L2 (LED array on PCB) value. The L1 value increase stems from a number of factors ranging from simply higher performing LEDs reducing the LED count, to L1 innovation such as high voltage LEDs, optimizing driver efficiency or to the use of high luminance LEDs enabling compact optics, allowing not only more design freedom but also cost reduction through space and weight savings. The L2 value increase is realized predominantly through increasing L2 performance with the use of algorithms that optimize L1 selection and placement and/or through L2 integration of drivers, control electronics, sensors, secondary lens and/or environmental protection, which is also initiating level collapse in the value chain. In this paper we will present the L1 and L2 innovations that are enabling this disruption as well as provide examples of fixture/luminaire level benefits.

  12. CVC Funding and Technological Evolution

    DEFF Research Database (Denmark)

    Corredoira, Rafael; Di Lorenzo, Francesco

    . In particular, we argue that CVC acquisition of power over the syndicate facilitates the transfer of capabilities to the new venture and that in turn helps the new venture to generate more influential inventions. Based on semiconductor industry data from 1985 to 1995 and after accounting for selection...... on the CVC investment process, our regression results show that the power of the CVC over the syndicate is associated to new venture’s inventions with more influence on the evolution of technology. In addition, the effect decreases when power is derived from older investments. This suggests a “honeymoon......How the interaction of incumbents and new ventures drives economic growth has been at the center of attention since early Schumpeter’s work. In this paper, we focus on whether corporate investment moves the technological position of the new venture toward the technological frontier or not...

  13. Multichip on Aluminum Metal Plate Technology for High Power LED Packaging

    Institute of Scientific and Technical Information of China (English)

    Choong-mo NAM; Mi-hee JI

    2010-01-01

    Multichip on Aluminum Metal Plate(MOAMP) technology with simple structure and low thermal resistance is developed for effective heat removal of Light Emitting Diode(LED) p-n junction and LED lighting module to have high reliability. The thermal resistance of LED modules was numerical and experimental. Thermal resistance from the junction to aluminum metal plate, considering input power of LED module using MOAMP technology, is 3.02 K/W, 3.23 K/W for the measured and calculated, respectively. We expect that the reported MOAMP technology with low thermal resistance will be a promising solution for high power LED lighting modules.

  14. Integrated Automotive High-Power LED-Lighting Systems in 3D-MID Technology

    NARCIS (Netherlands)

    Thomas, W.

    2014-01-01

    The growing energy consumption of lighting as well as rising luminous efficacies and -fluxes of high-power Light Emitting Diodes (LEDs) have contributed to the widespread use of LEDs in modern lighting systems. One of the most prominent users of the LED-technology is automotive (exterior) lighting.

  15. Technology Analysis of Global Smart Light Emitting Diode (LED Development Using Patent Data

    Directory of Open Access Journals (Sweden)

    Sangsung Park

    2017-08-01

    Full Text Available Technological developments related to smart light emitting diode (LED systems have progressed rapidly in recent years. In this paper, patent documents related to smart LED technology are collected and analyzed to understand the technology development of smart LED systems. Most previous studies of the technology were dependent on the knowledge and experience of domain experts, using techniques such as Delphi surveys or technology road-mapping. These approaches may be subjective and lack robustness, because the results can vary according to the selected expert groups. We therefore propose a new technology analysis methodology based on statistical modeling to obtain objective and relatively stable results. The proposed method consists of visualization based on Bayesian networks and a linear count model to analyze patent documents related to smart LED technology. Combining these results, a global hierarchical technology structure is created that can enhance the sustainability in smart LED system technology. In order to show how this methodology could be applied to real-world problems, we carry out a case study on the technology analysis of smart LED systems.

  16. Utopia, Technology, and the Evolution of Society.

    Science.gov (United States)

    Lewis, Arthur O.

    1985-01-01

    Provides an overview of utopian writing and experimentation from Plato to the present, looking at the impact of technological advancement on the individual and the society and arguing that "appropriate technology" may well be an outcome of "evolution in action." (AYC)

  17. Session 21.1 - Observations, Advances in LED Technology, and Dark Sky Protection

    Science.gov (United States)

    Duriscoe, Dan M.

    2016-10-01

    The importance of dark sky protection, potential threats to further degradation from LED technology, the announcement of a new world atlas of artificial night sky brightness, and the use of color images from the orbiting International Space Station for monitoring potential sources of light pollution were discussed in the six talks of this session. It was clear from the presentations that the work of professional astronomy depends upon continued restraint in the use of outdoor lighting, especially new LED technology, which relies upon blue-rich sources to support the advantages of high luminous efficacy and resulting energy savings.

  18. Literacy and Technology: Integrating Technology with Small Group, Peer-Led Discussions of Literature

    Science.gov (United States)

    Coffey, Genya

    2012-01-01

    This review examines research of computer-mediated small group discussion of literature. The goal of this review is to explore several instructional formats for integrating print-based and new literacies skills. First, the theoretical foundations for the shift from teacher-led to student led discussion are outlined. Research exploring ways in…

  19. Evolution of Home Automation Technology

    Directory of Open Access Journals (Sweden)

    Mohd. Rihan

    2009-01-01

    Full Text Available In modern society home and office automation has becomeincreasingly important, providing ways to interconnectvarious home appliances. This interconnection results infaster transfer of information within home/offices leading tobetter home management and improved user experience.Home Automation, in essence, is a technology thatintegrates various electrical systems of a home to provideenhanced comfort and security. Users are grantedconvenient and complete control over all the electrical homeappliances and they are relieved from the tasks thatpreviously required manual control. This paper tracks thedevelopment of home automation technology over the lasttwo decades. Various home automation technologies havebeen explained briefly, giving a chronological account of theevolution of one of the most talked about technologies ofrecent times.

  20. Case study: technology initiative led to advanced lead optimization screening processes at Bristol-Myers Squibb, 2004-2009.

    Science.gov (United States)

    Zhang, Litao; Cvijic, Mary Ellen; Lippy, Jonathan; Myslik, James; Brenner, Stephen L; Binnie, Alastair; Houston, John G

    2012-07-01

    In this paper, we review the key solutions that enabled evolution of the lead optimization screening support process at Bristol-Myers Squibb (BMS) between 2004 and 2009. During this time, technology infrastructure investment and scientific expertise integration laid the foundations to build and tailor lead optimization screening support models across all therapeutic groups at BMS. Together, harnessing advanced screening technology platforms and expanding panel screening strategy led to a paradigm shift at BMS in supporting lead optimization screening capability. Parallel SAR and structure liability relationship (SLR) screening approaches were first and broadly introduced to empower more-rapid and -informed decisions about chemical synthesis strategy and to broaden options for identifying high-quality drug candidates during lead optimization.

  1. Evolution of Home Automation Technology

    OpenAIRE

    Mohd. Rihan; M. Salim Beg

    2009-01-01

    In modern society home and office automation has becomeincreasingly important, providing ways to interconnectvarious home appliances. This interconnection results infaster transfer of information within home/offices leading tobetter home management and improved user experience.Home Automation, in essence, is a technology thatintegrates various electrical systems of a home to provideenhanced comfort and security. Users are grantedconvenient and complete control over all the electrical homeappl...

  2. Assessment of LED Technology in Ornamental Post-Top Luminaires (Host Site: Sacramento, CA)

    Energy Technology Data Exchange (ETDEWEB)

    Tuenge, Jason R.

    2011-12-01

    The DOE Municipal Solid-State Street Lighting Consortium has evaluated four different LED replacements for existing ornamental post-top street lights in Sacramento, California. The project team was composed of the City and its consultant, PNNL (representing the Consortium), and the Sacramento Municipal Utility District. Product selection was finalized in March 2011, yielding one complete luminaire replacement and three lamp-ballast retrofit kits. Computer simulations, field measurements, and laboratory testing were performed to compare the performance and cost-effectiveness of the LED products relative to the existing luminaire with 100 W high-pressure sodium lamp. After it was confirmed the LED products were not equivalent to HPS in terms of initial photopic illumination, the following parameters were scaled proportionally to enable equitable (albeit hypothetical) comparisons: light output, input wattage, and pricing. Four replacement scenarios were considered for each LED product, incorporating new IES guidance for mesopic multipliers and lumen maintenance extrapolation, but life cycle analysis indicated cost effectiveness was also unacceptable. Although LED efficacy and pricing continue to improve, this project serves as a timely and objective notice that LED technology may not be quite ready yet for such applications.

  3. Digestive peptidase evolution in holometabolous insects led to a divergent group of enzymes in Lepidoptera.

    Science.gov (United States)

    Dias, Renata O; Via, Allegra; Brandão, Marcelo M; Tramontano, Anna; Silva-Filho, Marcio C

    2015-03-01

    Trypsins and chymotrypsins are well-studied serine peptidases that cleave peptide bonds at the carboxyl side of basic and hydrophobic L-amino acids, respectively. These enzymes are largely responsible for the digestion of proteins. Three primary processes regulate the activity of these peptidases: secretion, precursor (zymogen) activation and substrate-binding site recognition. Here, we present a detailed phylogenetic analysis of trypsins and chymotrypsins in three orders of holometabolous insects and reveal divergent characteristics of Lepidoptera enzymes in comparison with those of Coleoptera and Diptera. In particular, trypsin subsite S1 was more hydrophilic in Lepidoptera than in Coleoptera and Diptera, whereas subsites S2-S4 were more hydrophobic, suggesting different substrate preferences. Furthermore, Lepidoptera displayed a lineage-specific trypsin group belonging only to the Noctuidae family. Evidence for facilitated trypsin auto-activation events were also observed in all the insect orders studied, with the characteristic zymogen activation motif complementary to the trypsin active site. In contrast, insect chymotrypsins did not seem to have a peculiar evolutionary history with respect to their mammal counterparts. Overall, our findings suggest that the need for fast digestion allowed holometabolous insects to evolve divergent groups of peptidases with high auto-activation rates, and highlight that the evolution of trypsins led to a most diverse group of enzymes in Lepidoptera.

  4. Digestive peptidase evolution in holometabolous insects led to a divergent group of enzymes in Lepidoptera

    KAUST Repository

    Dias, Renata O.

    2015-03-01

    © 2015 Elsevier Ltd. Trypsins and chymotrypsins are well-studied serine peptidases that cleave peptide bonds at the carboxyl side of basic and hydrophobic l-amino acids, respectively. These enzymes are largely responsible for the digestion of proteins. Three primary processes regulate the activity of these peptidases: secretion, precursor (zymogen) activation and substrate-binding site recognition. Here, we present a detailed phylogenetic analysis of trypsins and chymotrypsins in three orders of holometabolous insects and reveal divergent characteristics of Lepidoptera enzymes in comparison with those of Coleoptera and Diptera. In particular, trypsin subsite S1 was more hydrophilic in Lepidoptera than in Coleoptera and Diptera, whereas subsites S2-S4 were more hydrophobic, suggesting different substrate preferences. Furthermore, Lepidoptera displayed a lineage-specific trypsin group belonging only to the Noctuidae family. Evidence for facilitated trypsin auto-activation events were also observed in all the insect orders studied, with the characteristic zymogen activation motif complementary to the trypsin active site. In contrast, insect chymotrypsins did not seem to have a peculiar evolutionary history with respect to their mammal counterparts. Overall, our findings suggest that the need for fast digestion allowed holometabolous insects to evolve divergent groups of peptidases with high auto-activation rates, and highlight that the evolution of trypsins led to a most diverse group of enzymes in Lepidoptera.

  5. A study on Aerosol jet printing technology in LED module manufacturing

    Science.gov (United States)

    Rudorfer, Andreas; Tscherner, Martin; Palfinger, Christian; Reil, Frank; Hartmann, Paul; Seferis, Ioannis E.; Zych, Eugeniusz; Wenzl, Franz P.

    2016-09-01

    State of the art fabrication of LED modules based on chip-on-board (COB) technology comprises some shortcomings both with respect to the manufacturing process itself but also with regard to potential sources of failures and manufacturing impreciseness. One promising alternative is additive manufacturing, a technology which has gained a lot of attention during the last years due to its materials and cost saving capabilities. Especially direct-write technologies like Aerosol jet printing have demonstrated advantages compared to other technological approaches when printing high precision layers or high precision electronic circuits on substrates which, as an additional advantage, also can be flexible and 3D shaped. Based on test samples and test structures manufactured by Aerosol jet printing technology, in this context we discuss the potentials of additive manufacturing in various aspects of LED module fabrication, ranging from the deposition of the die-attach material, wire bond replacement by printed electrical connects as well as aspects of high-precision phosphor layer deposition for color conversion and white light generation.

  6. Evolution of Indoor Positioning Technologies: A Survey

    Directory of Open Access Journals (Sweden)

    Ramon F. Brena

    2017-01-01

    Full Text Available Indoor positioning systems (IPS use sensors and communication technologies to locate objects in indoor environments. IPS are attracting scientific and enterprise interest because there is a big market opportunity for applying these technologies. There are many previous surveys on indoor positioning systems; however, most of them lack a solid classification scheme that would structurally map a wide field such as IPS, or omit several key technologies or have a limited perspective; finally, surveys rapidly become obsolete in an area as dynamic as IPS. The goal of this paper is to provide a technological perspective of indoor positioning systems, comprising a wide range of technologies and approaches. Further, we classify the existing approaches in a structure in order to guide the review and discussion of the different approaches. Finally, we present a comparison of indoor positioning approaches and present the evolution and trends that we foresee.

  7. Color deviation controlling of phosphor conformal coating by advanced spray painting technology for white LEDs.

    Science.gov (United States)

    Yang, Liang; Wang, Simin; Lv, Zhicheng; Liu, Sheng

    2013-04-01

    An advanced phosphor conformal coating technology is proposed, good correlated color temperature (CCT) and chromaticity uniformity samples are fabricated through phosphor spray painting technology. Spray painting technology is also suitable for phosphor conformal coating of whole LED wafers. The samples of different CCTs are obtained through controlling the phosphor film thickness in the range of 6-80 μm; CCT variation of samples can be controlled in the range of ±200 K. The experimental Δuv reveals that the spray painting method can obtain a much smaller CCT variation (Δuv of 1.36e(-3)) than the conventional dispensing method (Δuv of 11.86e(-3)) when the light is emitted at angles from -90° to +90°, and chromaticity area uniformity is also improved significantly.

  8. Conceptual and technological evolutions of particle accelerators

    Institute of Scientific and Technical Information of China (English)

    Lee C.Teng

    2009-01-01

    We give here an ordered list of all types of particle accelerators and exhibit how each type evolves conceptually and/or technologically from the preceding.This is in contrast to the usual "history of particle accelerators" in which unrelated accelerator types are listed in the chronological order.It is hoped that this discussion and understanding of the rationale and logic in the evolution of one accelerator type to the next will help to educe future inventions.

  9. Analysis of the Science and Technology Preservice Teachers' Opinions on Teaching Evolution and Theory of Evolution

    Science.gov (United States)

    Töman, Ufuk; Karatas, Faik Özgür; Çimer, Sabiha Odabasi

    2014-01-01

    In this study, we investigate of science and technology teachers' opinions about the theory of evolution and the evolution teaching. The aim of this study, we investigate of science and technology teachers' opinions about the theory of evolution and the evolution teaching. This study is a descriptive study. Open-ended questions were used to…

  10. Development of an open technology sensor suite for assisted living: a student-led research project.

    Science.gov (United States)

    Manton, James D; Hughes, Josephine A E; Bonner, Oliver; Amjad, Omar A; Mair, Philip; Miele, Isabella; Wang, Tiesheng; Levdik, Vitaly; Hall, Richard D; Baekelandt, Géraldine; Vasconcellos, Fernando da Cruz; Hadeler, Oliver; Hutter, Tanya; Kaminski, Clemens F

    2016-08-01

    Many countries have a rapidly ageing population, placing strain on health services and creating a growing market for assistive technology for older people. We have, through a student-led, 12-week project for 10 students from a variety of science and engineering backgrounds, developed an integrated sensor system to enable older people, or those at risk, to live independently in their own homes for longer, while providing reassurance for their family and carers. We provide details on the design procedure and performance of our sensor system and the management and execution of a short-term, student-led research project. Detailed information on the design and use of our devices, including a door sensor, power monitor, fall detector, general in-house sensor unit and easy-to-use location-aware communications device, is given, with our open designs being contrasted with closed proprietary systems. A case study is presented for the use of our devices in a real-world context, along with a comparison with commercially available systems. We discuss how the system could lead to improvements in the quality of life of older users and increase the effectiveness of their associated care network. We reflect on how recent developments in open source technology and rapid prototyping increase the scope and potential for the development of powerful sensor systems and, finally, conclude with a student perspective on this team effort and highlight learning outcomes, arguing that open technologies will revolutionize the way in which technology will be deployed in academic research in the future.

  11. Luminescence and the light emitting diode the basics and technology of leds and the luminescence properties of the materials

    CERN Document Server

    Williams, E W; Pamplin, BR

    2013-01-01

    Luminescence and the Light Emitting Diode: The Basics and Technology of LEDS and the Luminescence Properties of the Materials focuses on the basic physics and technology of light emitting diodes (LEDS) and pn junction lasers as well as their luminescence properties. Optical processes in semiconductors and the useful devices which can be made are discussed. Comprised of 10 chapters, this book begins with an introduction to the crystal structure and growth, as well as the optical and electrical properties of LED materials. The detailed fabrication of the LED is then considered, along with the lu

  12. The evolution of an ancient technology.

    Science.gov (United States)

    Buckley, Christopher D; Boudot, Eric

    2017-05-01

    We investigate pattern and process in the transmission of traditional weaving cultures in East and Southeast Asia. Our investigation covers a range of scales, from the experiences of individual weavers ('micro') to the broad-scale patterns of loom technologies across the region ('macro'). Using published sources, we build an empirical model of cultural transmission (encompassing individual weavers, the household and the community), focussing on where cultural information resides and how it is replicated and how transmission errors are detected and eliminated. We compare this model with macro-level outcomes in the form of a new dataset of weaving loom technologies across a broad area of East and Southeast Asia. The lineages of technologies that we have uncovered display evidence for branching, hybridization (reticulation), stasis in some lineages, rapid change in others and the coexistence of both simple and complex forms. There are some striking parallels with biological evolution and information theory. There is sufficient detail and resolution in our findings to enable us to begin to critique theoretical models and assumptions that have been produced during the last few decades to describe the evolution of culture.

  13. Evolution of technology for automated peritoneal dialysis.

    Science.gov (United States)

    Ronco, Claudio; Amerling, Richard; Dell'aquila, Roberto; Rodighiero, Maria Pia; Di Loreto, Pierluigi

    2006-01-01

    Automated peritoneal dialysis (APD) is important for the further penetration of PD in the dialysis marketplace. Long dwell, equilibration PD (CAPD) has limited applicability in many patients due to inadequate solute clearance or fast membrane transport characteristics. Providing large volumes of dialysate over circumscribed hours is highly labor intensive without an automated system. Early attempts at APD were crude but effective in reducing labor, which was generally provided by nursing staff. Later evolution of PD technology has been greatly accelerated by the microchip, and by miniaturization of components. Current generation machines allow individualized fill volumes, variable tidal volumes and additional daytime automated exchanges, teledialysis, memorized delivery control, and full portability. The ideal machine should not only be able to perform all treatment schedules, but it should also optimize the performance of a selected treatment strategy. Biocompatible solutions, improved osmotic agents, and sorbent technology are all adaptable to APD. The eventual evolution toward continuous flow PD will resolve many of the current problems with both CAPD and APD.

  14. An Easy to Deploy Street Light Control System Based on Wireless Communication and LED Technology

    Directory of Open Access Journals (Sweden)

    Jesús Villadangos

    2013-05-01

    Full Text Available This paper presents an intelligent streetlight management system based on LED lamps, designed to facilitate its deployment in existing facilities. The proposed approach, which is based on wireless communication technologies, will minimize the cost of investment of traditional wired systems, which always need civil engineering for burying of cable underground and consequently are more expensive than if the connection of the different nodes is made over the air. The deployed solution will be aware of their surrounding’s environmental conditions, a fact that will be approached for the system intelligence in order to learn, and later, apply dynamic rules. The knowledge of real time illumination needs, in terms of instant use of the street in which it is installed, will also feed our system, with the objective of providing tangible solutions to reduce energy consumption according to the contextual needs, an exact calculation of energy consumption and reliable mechanisms for preventive maintenance of facilities.

  15. LED灯具低压驱动技术%LED Lighting with Low-voltage-driven Technology

    Institute of Scientific and Technical Information of China (English)

    颜重光

    2009-01-01

    It analyzed the technical requirements of LED lamp with Low-voltage driver IC from the perspective of the technology and the market economy, the working principle and application of IC technology,briefly introduced the working principle and application technology of LED driver IC for family lighting,%从技术和市场经济的角度对LED灯具低压驱动IC的技术要求进行分析,简述家庭照明用LED驱动IC工作原理和应用技术.

  16. Biometric Systems: Evolution, Applications and Technology

    Directory of Open Access Journals (Sweden)

    Deepti

    2014-11-01

    Full Text Available Biometrics is a futuristic and yet a current technology, with an ever bigger role in the future. Biometrics will not be able to replace passwords, swipe cards, or pin numbers etc., rather work with them in enhancing security in a simple, reliable, and cost effective way. Biometrics revolution has led to over 1 billion people being already covered by biometric identification programs in the lower middle income countries. Biometric system covers application pertaining to Authentication, Transaction, Access Privilege and it relies on Credentials, Demographics and Sensor data to get a match score with certain degree of confidence using biometric recognition tools. Biometrics systems are extremely useful due to its traits such as security (stop unauthorised person from getting access, convenience (No need to carry credentials like Identity proofs etc., Audit trail (creates an audit trail for say bank vault access etc., Fraud prevention (verifying if credit card holder is rightful owner at PoS, and de-duplication (One person, one documentation. India’s well known and ambitious pan-India project of Adhaar Card is one good example relying on biometric application for generating unique identification and de-duplication for wide ranging government schemes

  17. BIOMETRIC SYSTEMS: EVOLUTION, APPLICATIONS AND TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    Deepti Kumar

    2015-10-01

    Full Text Available Biometrics is a futuristic and yet a current technology, with an ever bigger role in the future. Biometrics will not be able to replace passwords, swipe cards, or pin numbers etc., rather work with them in enhancing security in a simple, reliable, and cost effective way. Biometrics revolution has led to over 1 billion people being already covered by biometric identification programs in the lower middle income countries. Biometric system covers application pertaining to Authentication, Transaction, Access Privilege and it relies on Credentials, Demographics and Sensor data to get a match score with certain degree of confidence using biometric recognition tools. Biometrics systems are extremely useful due to its traits such as security (stop unauthorised person from getting access, convenience (No need to carry credentials like Identity proofs etc., Audit trail (creates an audit trail for say bank vault access etc., Fraud prevention (verifying if credit card holder is rightful owner at PoS, and de-duplication (One person, one documentation. India’s well known and ambitious pan-India project of Adhaar Card is one good example relying on biometric application for generating unique identification and de-duplication for wide ranging government schemes.

  18. LED driver thermal design considerations for solid-state lighting technologies

    NARCIS (Netherlands)

    Perpiñà, X.; Werkhoven, R.J.; Vellvehi, M.; Jordà, X.; Kunen, J.M.G.; Jakovenko, J.; Bancken, P.; Bolt, P.J.

    2012-01-01

    This paper summarizes a study into the thermal influence of an LED driver board on an SSL Lamp. Full thermal characterization of an LED lamp and driver board is carried out by infrared thermography and by monitoring specific locations with thermocouples. The experimental results have been used to se

  19. LED driver thermal design considerations for solid-state lighting technologies

    NARCIS (Netherlands)

    Perpiñà, X.; Werkhoven, R.J.; Vellvehi, M.; Jordà, X.; Kunen, J.M.G.; Jakovenko, J.; Bancken, P.; Bolt, P.J.

    2012-01-01

    This paper summarizes a study into the thermal influence of an LED driver board on an SSL Lamp. Full thermal characterization of an LED lamp and driver board is carried out by infrared thermography and by monitoring specific locations with thermocouples. The experimental results have been used to

  20. WiMAX technology and network evolution

    CERN Document Server

    Etemad, Kamran

    2010-01-01

    WiMAX, the Worldwide Interoperability for Microwave Access, represents a paradigm shift in telecommunications technology. It offers the promise of cheaper, smaller, and simpler technology compared to existing broadband options such as DSL, cable, fiber, and 3G wireless.

  1. Research and Development for Technology Evolution Potential Forecasting System

    Science.gov (United States)

    Gao, Changqing; Cao, Shukun; Wang, Yuzeng; Ai, Changsheng; Ze, Xiangbo

    Technology forecasting is a powerful weapon for many enterprises to gain an animate future. Evolutionary potential radar plot is a necessary step of some valuable methods to help the technology managers with right technical strategy. A software system for Technology Evolution Potential Forecasting (TEPF) with automatic radar plot drawing is introduced in this paper. The framework of the system and the date structure describing the concrete evolution pattern are illustrated in details. And the algorithm for radar plot drawing is researched. It is proved that the TEPF system is an effective tool during the technology strategy analyzing process with a referenced case study.

  2. Exploring the evolution of investment pattern on advanced manufacturing technology

    DEFF Research Database (Denmark)

    Yang, Cheng; Matthiesen, Rikke Vestergaard; Johansen, John

    2014-01-01

    This paper explores the evolution of investment pattern on advanced manufacturing technology in a manner that builds on a longitudinal perspective. Based on the data of investments in AMTs from 567 manufacturing companies this paper develops a longitudinal taxonomy defined by the evolution...

  3. The Co-evolution of Internationalization and Technological Knowledge

    DEFF Research Database (Denmark)

    Geisler Asmussen, Christian; Hashai, Niron; Delios, Andrew

    2011-01-01

    This paper develops a formal model that captures the dynamic and mutual interdependency in the technological and international expansion of multinational enterprises (MNEs), thus offering a novel evolutionary theory of the MNE. The model, which is verified empirically, suggests a positive...... but diminishing effect of technological knowledge on internationalization and vice versa. This relationship leads to equilibrium in the technological knowledge-internationalization space that dictates the patterns of technological and international evolution of MNEs. The model offers an integrative approach...

  4. Information Technologies as Vehicles of Evolution.

    Science.gov (United States)

    Levinson, Paul

    Technology contributes to the growth of human knowledge in five distinct, though overlapping, ways: (1) all technologies are material embodiments and thus more or less durable records of ideas that have survived some test with external reality; (2) telescopes, microscopes, and similar technologies extend external experience and knowledge to areas…

  5. Development of Key Technologies for White Lighting Based on Light-Emitting Diodes (LEDs)

    Energy Technology Data Exchange (ETDEWEB)

    Werner Goetz; Bill Imler; James Kim; Junko Kobayashi; Andrew Kim; Mike Krames; Rick Mann; Gerd Mueller-Mach; Anneli Munkholm; Jonathan Wierer

    2004-03-31

    This program was organized to focus on materials development issues critical to the acceleration of solid-state lighting, and was split into three major thrust areas: (1) study of dislocation density reduction for GaN grown on sapphire using 'cantilever epitaxy', and the impact of dislocation density on the performance of state-of-the-art high-power LEDs; (2) the evaluation of in situ techniques for monitoring gas phase chemistry and the properties of GaN-based layers during metal-organic vapor phase epitaxy (MOCVD), and (3) feasibility for using semiconductor nanoparticles ('quantum dots') for the down-conversion of blue or ultraviolet light to generate white light. The program included a partnership between Lumileds Lighting (epitaxy and device fabrication for high power LEDs) and Sandia National Laboratories (cantilever epitaxy, gas phase chemistry, and quantum dot synthesis). Key findings included: (1) cantilever epitaxy can provide dislocation density reduction comparable to that of more complicated approaches, but all in one epitaxial growth step; however, further improvements are required to realize significant gains in LED performance at high drive currents, (2) in situ tools can provide detailed knowledge about gas phase chemistry, and can be used to monitor and control epitaxial layer composition and temperature to provide improved yields (e.g., a fivefold increase in color targeting is demonstrated for 540nm LEDs), and (3) quantum efficiency for quantum dots is improved and maintained up to 70% in epoxy thin films, but further work is necessary to increase densification (absorption) and robustness before practical application to LEDs.

  6. Semi-polar GaN materials technology for high IQE green LEDs.

    Energy Technology Data Exchange (ETDEWEB)

    Koleske, Daniel; Lee, Stephen Roger; Crawford, Mary H; Coltrin, Michael Elliott; Fini, Paul

    2013-06-01

    The goal of this NETL funded program was to improve the IQE in green (and longer wavelength) nitride- based LEDs structures by using semi-polar GaN planar orientations for InGaN multiple quantum well (MQW) growth. These semi-polar orientations have the advantage of significantly reducing the piezoelectric fields that distort the QW band structure and decrease electron-hole overlap. In addition, semipolar surfaces potentially provide a more open surface bonding environment for indium incorporation, thus enabling higher indium concentrations in the InGaN MQW. The goal of the proposed work was to select the optimal semi-polar orientation and explore wafer miscuts around this orientation that produced the highest quantum efficiency LEDs. At the end of this program we had hoped to have MQWs active regions at 540 nm with an IQE of 50% and an EQE of 40%, which would be approximately twice the estimated current state-of-the-art.

  7. [Study of the effect of fluoride removal agent and microabrasion technology in LED teeth whitening of dental fluorosis].

    Science.gov (United States)

    Jia, Yan; Zhang, Rong; Luo, Hong-Xia; Li, Ping; Zhang, Chun-Lei

    2016-10-01

    To evaluate the effect of fluoride removal agent and microabrasion technology in LED teeth whitening of dental fluorosis. One hundred and twelve patients with moderate dental fluorosis treated from August 2012 to July 2015 were divided into experimental group and control group according to random number table, with 61 cases in each group. In addition to pretreatment for all patients, patients in the control group were given combined treatment of Beyond LED whitening and fluoride removal agent; while patients in the experimental group were given microabrasion before LED whitening, with the same subsequent treatment process as that in the control group. The whitening effect and tooth sensitivity during whitening were compared between the two groups at the completion of treatment, 1 month and 6 months after treatment. SPSS 19.0 software package was employed for statistical analysis. There were no ineffective or lost patients in 2 groups. The effective rate of whitening for patients in the experimental group at completion of treatment, 1 month and 6 months after treatment was significantly higher than that in the control group (P0.05). Combined treatment with fluoride removal agent and microabrasion technology in LED teeth whitening for dental fluorosis can significantly improve the whitening effect and will not interfered by significantly increased tooth sensitivity.

  8. MANUS: the evolution of an assistive technology

    NARCIS (Netherlands)

    Verburg, G.; Kwee, H.H.; Wisaksana, A.; Cheetham, A.; Woerden, J.A. van

    1996-01-01

    Manus is a wheelchair mounted robotic arm that was designed for people who have significant impairment in function of all limbs. The process of development, user testing, and product modifications is described, with special emphasis on evaluations by consumers. After an evolution of 20 years, Manus

  9. Shaping Future Green Cities: LEDs Technology adoption as an option for India

    OpenAIRE

    Singh, R; Kroesen, J.O.

    2010-01-01

    The sustainable development in developing and newly industrialising countries (China, India, South Africa, and Brazil) is central issue for policy makers, decision makers, academic, and planners. The attainment of sustainability has become a challenge for rapidly urbanising India. The paper focuses on the challenges for building less energy consuming cities. The cities use different technologies for lighting purposes but which technology can decarbonise them in future. Moreover, the question ...

  10. The Co-evolution of Internationalization and Technological Knowledge

    DEFF Research Database (Denmark)

    Geisler Asmussen, Christian; Hashai, Niron; Delios, Andrew

    2011-01-01

    This paper develops a formal model that captures the dynamic and mutual interdependency in the technological and international expansion of multinational enterprises (MNEs), thus offering a novel evolutionary theory of the MNE. The model, which is verified empirically, suggests a positive...... but diminishing effect of technological knowledge on internationalization and vice versa. This relationship leads to equilibrium in the technological knowledge-internationalization space that dictates the patterns of technological and international evolution of MNEs. The model offers an integrative approach...... for explaining different views in extant literature regarding the technological and international expansion of firms....

  11. Social organization and the evolution of cumulative technology in apes and hominins.

    Science.gov (United States)

    Pradhan, Gauri R; Tennie, Claudio; van Schaik, Carel P

    2012-07-01

    Culturally supported accumulation (or ratcheting) of technological complexity is widely seen as characterizing hominin technology relative to that of the extant great apes, and thus as representing a threshold in cultural evolution. To explain this divide, we modeled the process of cultural accumulation of technology, which we defined as adding new actions to existing ones to create new functional combinations, based on a model for great ape tool use. The model shows that intraspecific and interspecific variation in the presence of simple and cumulative technology among extant orangutans and chimpanzees is largely due to variation in sociability, and hence opportunities for social learning. The model also suggests that the adoption of extensive allomaternal care (cooperative breeding) in early Pleistocene Homo, which led to an increase in sociability and to teaching, and hence increased efficiency of social learning, was enough to facilitate technological ratcheting. Hence, socioecological changes, rather than advances in cognitive abilities, can account for the cumulative cultural changes seen until the origin of the Acheulean. The consequent increase in the reliance on technology could have served as the pacemaker for increased cognitive abilities. Our results also suggest that a more important watershed in cultural evolution was the rise of donated culture (technology or concepts), in which technology or concepts was transferred to naïve individuals, allowing them to skip many learning steps, and specialization arose, which allowed individuals to learn only a subset of the population's skills. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Evolution of Database Replication Technologies for WLCG

    CERN Document Server

    Baranowski, Zbigniew; Blaszczyk, Marcin; Dimitrov, Gancho; Canali, Luca

    2015-01-01

    In this article we summarize several years of experience on database replication technologies used at WLCG and we provide a short review of the available Oracle technologies and their key characteristics. One of the notable changes and improvement in this area in recent past has been the introduction of Oracle GoldenGate as a replacement of Oracle Streams. We report in this article on the preparation and later upgrades for remote replication done in collaboration with ATLAS and Tier 1 database administrators, including the experience from running Oracle GoldenGate in production. Moreover, we report on another key technology in this area: Oracle Active Data Guard which has been adopted in several of the mission critical use cases for database replication between online and offline databases for the LHC experiments.

  13. ICESat-2 laser technology readiness level evolution

    Science.gov (United States)

    Sawruk, Nicholas W.; Burns, Patrick M.; Edwards, Ryan E.; Wysocki, Theodore; VanTuijl, Andre; Litvinovitch, Viatcheslav; Sullivan, Edward; Hovis, Floyd E.

    2015-02-01

    We report on the completion of the space qualification testing program for NASA Goddard Space Flight Center's (GSFC) Ice, Cloud, and Land Elevation Satellite 2 (ICESat-2) program. This paper describes the final performance results of the fully integrated (laser and electronics) flight laser system with an emphasis on the system design evolution from a breadboard demonstration to a fully space-qualified laser system. The 532 nm ICESat-2 laser transmitter generates diffraction limited pulse energies of 1 mJ, pulsewidths of laser development to facilitate future space-qualified laser developments, improve reliability, and increase performance.

  14. Achieving cost reductions in EOSDIS operations through technology evolution

    Science.gov (United States)

    Newsome, Penny; Moe, Karen; Harberts, Robert

    1996-01-01

    The earth observing system (EOS) data information system (EOSDIS) mission includes the cost-effective management and distribution of large amounts of data to the earth science community. The effect of the introduction of new information system technologies on the evolution of EOSDIS is considered. One of the steps taken by NASA to enable the introduction of new information system technologies into the EOSDIS is the funding of technology development through prototyping. Recent and ongoing prototyping efforts and their potential impact on the performance and cost-effectiveness of the EOSDIS are discussed. The technology evolution process as it related to the effective operation of EOSDIS is described, and methods are identified for the support of the transfer of relevant technology to EOSDIS components.

  15. Direct-lit LED backlight technology for improving the picture quality%改善显示品质的直下式 LED 背光技术

    Institute of Scientific and Technical Information of China (English)

    吴丽; 沈健; 徐立国

    2014-01-01

    Through theoretical analysis,RGB three primaries LED backlighting with appropriate line is chosen in a LCD backlight with narrow gamut,which can raise the color gamut from 40% to 70%. And the test fitted well with analysis,but the mixing ratio of three primaries direct-lit backlight is 1.3∶1,larger than 1 ∶ 1 of full white backlight.The white LEDs were doped into three primaries LED backlight,which can reduce the mixing ratio.As the brightness of the white light increases, color gamut will be reduced.When color gamut changes from 70.2% to 63.7%,the white luminance is 30% of the total luminance,and the mixing ratio is descended to 1.1∶1.%通过理论分析,在窄色域液晶屏的背光中选择合适谱线的 RGB 三基色 LED 背光,可以将显示器的色域从40%提升至70%.试验结果与理论相符合,但是三基色直下式背光的混光比为1.3∶1,比全白灯背光的1∶1大.在三基色LED 背光中加入 LED 白灯,能够降低混光比.白光灯的亮度逐步增加时,色域会降低.当色域从70.2%下降到63.7%时,白灯发出的亮度占总亮度的30%,混光比也降低为1.1∶1.

  16. Technology evolution of the Tropomi instrument

    NARCIS (Netherlands)

    Vries, J. de; Hoogeveen, R.; Voors, R.; Kleipool, Q.; Veefkind, P.; Aben, I.; Snel, R.; Valk, N.C.J. van der; Visser, H.; Otter, G.C.J.

    2012-01-01

    TROPOMI is the sun backscatter trace gas instrument on ESA's Sentinel-5 precursor satellite. TROPOMI builds upon a rich heritage from similar instruments, the main ones being SCIAMACHY on ESA's ENVISAT and OMI on NASA's AURA satellite. This paper explains how the technology from the heritage instrum

  17. Technology evolution of the Tropomi instrument

    NARCIS (Netherlands)

    Vries, J. de; Hoogeveen, R.; Voors, R.; Kleipool, Q.; Veefkind, P.; Aben, I.; Snel, R.; Valk, N.C.J. van der; Visser, H.; Otter, G.C.J.

    2012-01-01

    TROPOMI is the sun backscatter trace gas instrument on ESA's Sentinel-5 precursor satellite. TROPOMI builds upon a rich heritage from similar instruments, the main ones being SCIAMACHY on ESA's ENVISAT and OMI on NASA's AURA satellite. This paper explains how the technology from the heritage

  18. Evolution and Future of Torque Measurement Technology

    Directory of Open Access Journals (Sweden)

    Dr. W. Krimmel

    2006-03-01

    Full Text Available The journey to the past of torque measurement technology begins in the 17th century. It takes us from the first incipiencies of torque measurement to the problem of the transfer of the measurement signal from a rotating shaft, which existed for several decades. This task was solved by the integration of high-precise digital measuring amplifiers in the torque sensors, which is expressed by broad application fields, today. The future will appertain to highly dynamic measuring sensors as well as to intelligent torque sensors, which are able to transmit their sensor-specific characteristics to evaluation devices.

  19. Deviation Among Technology Reviews: An Informative Enrichment of Technology Evolution Theory for Marketing

    NARCIS (Netherlands)

    A. Sood (Ashish); S. Stremersch (Stefan)

    2010-01-01

    textabstractUnderstanding technological change is of critical importance to marketers, as it bears new markets, new brands, new customers, and new market leaders. This paper examines the deviation among reviews of a technology’s performance and its consequences for inferences on technology evolution

  20. Evolution of Water Supply, Sanitation, Wastewater, and Stormwater Technologies Globally

    Directory of Open Access Journals (Sweden)

    Andreas N. Angelakis

    2015-02-01

    Full Text Available This paper provides an outline of history of hydro-technologies in the west and the east. It is an overview of the special issue on “the evolution of hydro-technologies globally”, in which the key topics regarding the history of water and sanitation worldwide, and its importance to future cities are presented and discussed. It covers a wide range of relevant historical issues, and is presented in three categories: productivity assessment, institutional framework and mechanisms, and governance aspects. This paper concludes by discussing the challenges on future research in this field of study.

  1. LEDs for greenhouse lighting

    NARCIS (Netherlands)

    Nederhoff, E.M.

    2010-01-01

    Light Emitting Diodes (LED's) are a promising technology for greenhouse lighting with their efficiency to activate plant photosynthesis potentially higher in red LEDs than in HPS lamps. Due to their particular light colour, LEDs can initiate special effects in plants or steer plant processes and

  2. From Darwinian to technological evolution: forgetting the human lottery.

    Science.gov (United States)

    Tintino, Giorgio

    2014-01-01

    The GRIN technologies (-geno, -robo, -info, -nano) promise to change the inner constitution of human body and its own existence. This transformation involves the structure of our lives and represent a brave new world that we have to explore and to manage. In this sense, the traditional tools of humanism seems very inadequate to think the biotech century and there is a strong demand of a new thought for the evolution and the concrete history of life. The posthuman philosophy tries to take this new path of human existence in all of its novelty since GRIN technologies seem to promise new and unexpected paths of evolution to living beings and, above all, man. For this, the post-human thought, as we see, is a new anthropological overview on the concrete evolution of human being, an overview that involves an epistemological revolution of the categories that humanism uses to conceptualize the journey that divides the Homo sapiens from the man. But, is this right?

  3. The evolution of telemedicine and nano-technology

    Science.gov (United States)

    Park, Dong Kyun; Young Jung, Eun; Chan Moon, Byung

    2012-10-01

    This paper will cover definition and history of telemedicine, changes in medical paradigm and roll of telemedicine and roll of nano-technology for evolution of telemedicine. Hypothetically, telemedicine is distance communication for medical purpose and modern definition explains telemedicine as `a system of health care delivery in which physicians examine distant patients through the use of telecommunications technology. Medical service will change to personalized medicine based on gene information to prevent and manage diseases due to decrease of acute diseases, population aging and increase of prevalence in chronic diseases, which means current medical services based on manualized treatment for diseases will change to personalized medicine based on individual gene information. Also, international healthcare will be activated to provide high quality medical services with low cost using developed transportation. Moreover, hospital centered medical services will change to patients centered medical service due to increase of patient's rights. Development in sensor technology is required for telemedicine to be applied as basic infrastructure for medical services. Various researches in nano-biosensor field are conducted due to introduction of new technologies. However, most researches are in fundamental levels that requires more researches for stability and clinical usefulness. Nano technology is expected to achieve innovative development and define new criteria for disease prevention and management.

  4. Sustainable Data Evolution Technology for Power Grid Optimization

    Energy Technology Data Exchange (ETDEWEB)

    2017-10-09

    The SDET Tool is used to create open-access power grid data sets and facilitate updates of these data sets by the community. Pacific Northwest National Laboratory (PNNL) and its power industry and software vendor partners are developing an innovative sustainable data evolution technology (SDET) to create open-access power grid datasets and facilitate updates to these datasets by the power grid community. The objective is to make this a sustained effort within and beyond the ARPA-E GRID DATA program so that the datasets can evolve over time and meet the current and future needs for power grid optimization and potentially other applications in power grid operation and planning.

  5. An Overview on Wireless Sensor Networks Technology and Evolution

    Directory of Open Access Journals (Sweden)

    Chiara Buratti

    2009-08-01

    Full Text Available Wireless sensor networks (WSNs enable new applications and require non-conventional paradigms for protocol design due to several constraints. Owing to the requirement for low device complexity together with low energy consumption (i.e., long network lifetime, a proper balance between communication and signal/data processing capabilities must be found. This motivates a huge effort in research activities, standardization process, and industrial investments on this field since the last decade. This survey paper aims at reporting an overview of WSNs technologies, main applications and standards, features in WSNs design, and evolutions. In particular, some peculiar applications, such as those based on environmental monitoring, are discussed and design strategies highlighted; a case study based on a real implementation is also reported. Trends and possible evolutions are traced. Emphasis is given to the IEEE 802.15.4 technology, which enables many applications of WSNs. Some example of performance characteristics of 802.15.4-based networks are shown and discussed as a function of the size of the WSN and the data type to be exchanged among nodes.

  6. The evolution of wireless video transmission technology for surveillance missions

    Science.gov (United States)

    Durso, Christopher M.; McCulley, Eric

    2012-06-01

    Covert and overt video collection systems as well as tactical unmanned aerial vehicles (UAV's) and unmanned ground vehicles (UGV's) can deliver real-time video intelligence direct from sensor systems to command staff providing unprecedented situational awareness and tactical advantage. Today's tactical video communications system must be secure, compact, lightweight, and fieldable in quick reaction scenarios. Four main technology implementations can be identified with the evolutionary development of wireless video transmission systems. Analog FM led to single carrier digital modulation, which gave way to multi-carrier orthogonal modulation. Each of these systems is currently in use today. Depending on the operating environment and size, weight, and power limitations, a system designer may choose one over another to support tactical video collection missions.

  7. LED lamp

    Science.gov (United States)

    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.

  8. Spatial Dynamics of Technological Evolution: Technological Relatedness as Driver for Radical Emerging Technologies

    DEFF Research Database (Denmark)

    Tanner, Anne Nygaard

    over time, economic geographers have been occupied by accumulation of knowledge in space. For long, it has been discussed whether Marshallian specialization or Jacobian diversification externalities favor regional innovativeness. In the case of radical innovation, studies have found empirical support...... hypothesis that the accumulation of knowledge at the regional level is an important driver for the emergence of radical technology. The paper focuses on the case of fuel cell (FC) technology, which is argued to be a radical technology, understood as a disruption and discontinuation of technological...... trajectories. In more details, the paper tests two opposing hypotheses: 1) A diverse regional knowledge base leads to radical innovation, and 2) Related Variety in the regional knowledge base leads to radical innovation. And two specific hypotheses for the emergence of FC technology: 3) FC technological...

  9. Large area LED package

    Science.gov (United States)

    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.

  10. The cost of radiotherapy in a decade of technology evolution.

    Science.gov (United States)

    Van de Werf, Evelyn; Verstraete, Jan; Lievens, Yolande

    2012-01-01

    To quantify changes in radiotherapy costs occurring in a decade of medical-technological evolution. The activity-based costing (ABC) model of the University Hospitals Leuven (UHL) radiotherapy (RT) department was adapted to current RT standards. It allocated actual resource costs to the treatments based on the departmental work-flow and patient mix in 2009. A benchmark with the former model analyzed the cost increases related to changes in RT infrastructure and practice over 10 years. A considerable increase in total RT costs was observed, resulting from higher capital investments (96%) and personnel cost (103%), the latter dominating the total picture. Treatment delivery remains the most costly activity, boosted by the cost of improved quality assurance (QA), 23% of total product costs, coming along with more advanced RT techniques. Hence, cost increases at the product level are most obvious for complex treatments, such as intensity-modulated radiotherapy (IMRT), representing cost increases ranging between 38% and 88% compared to conformal approaches. The ABC model provides insight into the financial consequences of evolving technology and practice. Such data are a mandatory first step in our strive to prove RT cost-effectiveness and thus support optimal reimbursement and provision of radiotherapy departments. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  11. Research of full color LED display cooling technology%全彩色LED显示屏散热技术的研究

    Institute of Scientific and Technical Information of China (English)

    燕希; 景占荣

    2013-01-01

    为了实现LED显示系统的散热的需求,在分析多种常用散热技术的基础上,提出并研究了半导体制冷技术在LED显示屏散热中的应用.半导体制冷的理论基础是赛贝尔效应和帕尔贴效应,研究表明该技术在理论上完全可行,有一定的应用潜力.%In order to realize the cooling of the LED display system,On the analysis of several common cooling technology fuondation,semiconductor refrigeration is designed in the appliction of LED display cooling.,Semiconductor refrigeration is based on the theory of Seebeck effect and Peltier effect,studies show that the technology in theory completely feasible,has the certain application potential.

  12. Naked Eye 3D Technology of Full Color LED Display Screen%浅谈全彩LED显示屏的裸眼3D技术

    Institute of Scientific and Technical Information of China (English)

    马小华

    2014-01-01

    This paper introduces the 3D stereo vision principle and 3 Naked-eye 3D display technology is applied to the principle of LED display screen and application method, several 3D autostereoscopic display quality technology application in the display of the LED potential analysis and research and discussion.%本文介绍了3D立体视觉原理以及三种裸眼3D显示技术应用到LED显示屏上的原理以及应用方法,对几种裸眼3D立体显示技术应用在LED显示屏上的优劣势进行分析和研究探讨。

  13. 建筑物LED景观工程安装施工技术%The Installation Construction Technology of LED Landscape Engineering Building

    Institute of Scientific and Technical Information of China (English)

    王基杰

    2013-01-01

    本文通过海沧商务中心、商务大厦及海投大厦LED夜景景观照明工程的实例来探讨提升建筑物 LED 景观工程安装施工技术。并利用该项新产品,用科学的方法精心进行景观照明设计与施工,使 LED 夜景景观照明的施工工艺更趋规范化、标准化。%In this article, the author bases on the Haicang bus-iness center, business building, and the lighting project of inve-stment building LED landscape in night to discuss and enhance the installation construction technology of LED landscape en-gineering, and takes advantage of the new product and scien-tific methods for landscape lighting design and meticulous co-nstruction to make LED night landscape lighting construction process more standardization.

  14. Key Technologies for Decentralized Control Platform with Dynamic Evolution for Railway Transportation System

    Institute of Scientific and Technical Information of China (English)

    Tan Yongdong; GuiXun; Qian Qingquan

    2006-01-01

    Key technologies as well as their principles were discussed for a decentralized control platform capable of dynamic evolution.The primary content includes the automatic decision-making mechanism and the algorithm of the control center migration, the principle and technology of system self-monitoring, the principle and technology of the switch-mode of remote control station, the information transmission technology, and the data consistency technology. These key technologies have shown a series of advanced characteristics for decentralized control platform.

  15. 2012 CCTV Spring Festival Gala Evening Stage Design: LED Technology of Visual Effects%2012年CCTV春节联欢晚会舞美LED视效技术

    Institute of Scientific and Technical Information of China (English)

    白明

    2012-01-01

    文章介绍了2012CCTV春晚中LED视效系统的实现方式:视效系统介绍、视效单元特点、控制系统介绍、视效技术展望。%2012 CCTV Spring Festival Gala LED visual effects system implementation. Visual effects system, the characteristics of the visual effects unit, control system, visual effects technology foresight.

  16. The Evolution of Academic Libraries in the Age of Technology

    Directory of Open Access Journals (Sweden)

    Yasaman Saharkhiz

    2017-01-01

    Full Text Available In the present age, one of the main elements in every country is information and its role in the development of countries. In such an era, universities are pioneers in development and knowledge production in which, academic libraries also play a significant role. In the design field, libraries that have long been synonymous with peace and tranquility are now considered as a place in which there should be a balance between quiet atmosphere and social dynamic mood. The aim of this study is to examine the evolution of spaces of academic libraries, which is constantly being changed as a result of technological advancements and alteration of old systems with new ones. Our research method includes reviewing similar domestic samples, conforming examples to library standards and examining the changing process of several foreign libraries over a period of time. The results of this study indicate that generally, modern libraries have fewer spaces for paper books and publications and individual study, instead, more spaces are dedicated to places for group studies and using computer. This change has influenced the function of the spaces, the relation between different parts of the library and people who use it.

  17. Self-reported Impacts of LED Lighting Technology Compared to Fuel-based Lighting on Night Market Business Prosperity in Kenya

    Energy Technology Data Exchange (ETDEWEB)

    Johnstone, Peter; Jacobson, Arne; Mills, Evan; Mumbi, Maina

    2009-02-11

    The notion of"productive use" is often invoked in discussions about whether new technologies improve productivity or otherwise enhance commerce in developing-country contexts. It an elusive concept,especially when quantitative measures are sought. Improved and more energy efficient illumination systems for off-gridapplication--the focus of the Lumina Project--provide a case in which a significant productivity benefit can be imagined, given the importance of light to the successful performance of many tasks, and the very low quality of baseline illumination provided by flame-based source. This Research Note summarizes self-reported quantitative and qualitative impacts of switching to LED lighting technology on the prosperity of night-market business owners and operators. The information was gathered in the context of our 2008 market testing field work in Kenya?s Rift Valley Province, which was performed in the towns of Maai Mahiu and Karagita by Arne Jacobson, Kristen Radecsky, Peter Johnstone, Maina Mumbi, and others. Maai Mahiu is a crossroads town; provision of services to travelers and freight carriers is a primary income source for the residents. In contrast, the primary income for Karagita's residents is from work in the large, factory style flower farms on the eastern shores of Lake Naivasha that specialize in producing cut flowers for export to the European market. According to residents, both towns had populations of 6,000 to 8,000 people in June 2008. We focused on quantifying the economics of fuel-based and LED lighting technology in the context of business use by night market vendors and shop keepers. Our research activities with the business owners and operators included baseline measurement of their fuel-based lighting use, an initial survey, offering for sale data logger equipped rechargeable LED lamps, monitoring the adoption of the LED lamps, and a follow-up survey.

  18. Research of Patent Layout on Chinese LED Backlighting Technology%中国LED背光技术专利布局现状分析

    Institute of Scientific and Technical Information of China (English)

    张弘第; 刘娅; 张旭

    2011-01-01

    The paper explored the competition landscape and development trends which are the commanding points of the LED backlighting technology from the perspective of the patent. It chooses the patents from 2003-2008 collected in the DII (Dement Innovations Index) patent database to study the patent layout of Chinas LED backlight technology in accordance with the following aspects: technology composition of the overall industry, countries (regions) and layout of the major technology companies and so on.%从专利的角度探究了液晶电视中的技术制高点—LED背光的竞争格局和发展趋势.选择DII( Derwent Innovations Index)专利数据库中2003~2008年的申请专利,分别从整体产业、国家(地区)、技术构成以及主要公司的技术布局等方面,研究了中国LED背光技术的专利布局情况.

  19. Light Emitting Diodes (LEDs)

    Science.gov (United States)

    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.

  20. The evolution of the laser: A systems perspective on science, technology and society

    Science.gov (United States)

    Deruiter, Willem

    The evolution of laser technology is addressed, and an attempt is made to correlate this evolution to the macrosociological theory of Juergen Habermas. The economic and social consequences of innovations are evaluated. Different laser applications are described. The evolution of the semiconductor laser is discussed. The evolution of optical telecommunication systems is outlined. The Habermas theory of communicative action, focussing on the theoretical distinction between 'system' and 'lifeworld,' is treated. The modified theory of Habermas is applied to the evolution of the laser. The embedding of a number of laser applications in the social context is discussed: laser isotope separation, compact disc players, and the Strategic Defense Initiative.

  1. Where Creativity Meets Technology: A Library-Led, Multi-Disciplinary Online Showcase for Artworks, Creative Writings, and Movies Displayed with 3D and HTML5 Technology

    Science.gov (United States)

    Wong, Shun Han Rebekah

    2015-01-01

    This article introduces the Hong Kong Baptist University's Heritage project (http://heritage.lib.hkbu.edu.hk/), a multi-disciplinary online showcase for curriculum-related creative outputs that were produced by faculty and students of the university. Initiated and led by the University Library, this project was a collaborative effort with six…

  2. Measuring the evolution of the drivers of technological innovation in the patent record.

    Science.gov (United States)

    Buchanan, Andrew; Packard, Norman H; Bedau, Mark A

    2011-01-01

    We argue that technology changes over time by an evolutionary process that is similar in important respects to biological evolution. The process is adaptive in the sense that technologies are selected because of their specific adaptive value and not at random, but this adaptive evolutionary process differs from the Darwinian process of random variation followed by natural selection. We find evidence for the adaptive evolution of technology in the US patent record, specifically, the public bibliographic information of all utility patents issued in the United States from 1976 through 2010. Patents record certain innovations in the evolution of technology. The 1976-2010 patent record is huge, containing almost four million patents. We use a patent's incoming citations to measure its impact on subsequent patented innovations. Weighting innovative impact by the dissimilarity between parent and child technologies reveals that many of the most fecund inventions are door-opening technologies that spawn innovations in widely diverse categories.

  3. Results of a nurse-led intervention: connecting pediatric cancer patients from the hospital to the school using videoconferencing technologies.

    Science.gov (United States)

    Ellis, Sarah J; Drew, Donna; Wakefield, Claire E; Saikal, Samra L; Punch, Deborah; Cohn, Richard J

    2013-01-01

    The objectives of this study were to assess the feasibility and perceived academic/psychosocial outcomes of a pilot program using videoconferencing facilities to connect children with cancer to their home school. Eight parents, three patients, and five teachers (n = 16) participated in semistructured interviews evaluating the efficacy/feasibility of this program. Results were analyzed using the qualitative framework of Miles and Huberman. Parents reported that videoconferencing provided the family with a sense of normalcy and connection to the outside world (4/8), often boosting patients' mood (6/8). Further benefits included stronger relationships with classmates and teachers (15/16) and improved peer acceptance and school reintegration. There were no notable impacts on patients' academic progression. Reported barriers included: costs, time commitments, bureaucratic hurdles, and technical and logistical difficulties. Videoconferencing technologies provide an important tool to connect childhood cancer patients to their classrooms; however, further solution-based investigation is warranted to overcome existing barriers.

  4. Competing Technologies and Industry Evolution: The Benefits of Making Mistakes in the Flat Panel Display Industry

    OpenAIRE

    Eggers, J.P.

    2010-01-01

    Managers at firms facing uncertain competing technologies evolving concurrently face a complex decision set, including options to invest in one technology or other, both technologies, or to wait to invest. This study investigates the role that experience, learning and timing play in affecting the firm-level pros and cons of each of these four strategies in a technological competition situation. Using a unique data set on the evolution of the global flat panel display industry, this study offe...

  5. Comparison of different LED Packages

    Science.gov (United States)

    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.

  6. 主动式3D立体技术在LED显示屏中的应用%Active Stereoscopic 3D Technology in LED Display

    Institute of Scientific and Technical Information of China (English)

    吴星华

    2012-01-01

    本文阐述了一种基于主动式3D显示技术在LED显示屏上实现的方案。文中通过分析前端3D输入信号的特点,着重解决LED显示屏接收高清3D信号的问题。同时为了配合观看3D视频时的高刷新率和高灰阶的要求,在显示单元中采用新一代的脉宽调制(PwM)驱动技术,用来改善显示屏的刷新率和灰阶。%In this article, we describe a new active stereoscopic 3D technology in LED display. The key of this system is the input 3D HD signal which should be analyzed first. The requirements of led display are high refresh rate and high gray scale when watching 3D videos. And it is using a new driving technology which is pulse width modulation in display units to improve the feeling of viewers.

  7. Professional Development and the Master Technology Teacher: The Evolution of One Partnership

    Science.gov (United States)

    Wright, Vivian H.

    2010-01-01

    This article describes the formation and evolution of a successful collaboration titled the "Master Technology Teacher", a professional development program that focuses on training teachers how to use technology in classroom instruction. Partners in the collaboration include inservice and preservice teachers and university content area…

  8. Thirty Years of Evolution in Instructional Technology, as Reflected in a Textbook

    Science.gov (United States)

    Smaldino, Sharon E.; Lowther, Deborah L.; Russell, James D.

    2011-01-01

    This article describes how a textbook has traced 30 years of evolution in instructional technology. One of the book's key continuing features is the ASSURE Model. To connect technology to learning, the Classroom Link was developed. As standards were formulated for teachers and students, they were included in the textbook. Other evolutionary…

  9. Reading and Thinking in Science and Technology: The Evolution of a Course.

    Science.gov (United States)

    Senior, Glenda; Reber, Dixie

    1989-01-01

    Describes the evolution of the Rochester Institute of Technology's course on reading and thinking in science and technology for hearing-impaired students, featuring instructional enrichment and problem-solving components that reinforce students' application of problem-solving approaches beyond the course. (CB) (Adjunct ERIC Clearinghouse on…

  10. An overview of the evolution of vibrating beam accelerometer technology

    Science.gov (United States)

    Norling, B. L.

    The history of vibrating beam accelerometers (VBA) is briefly outlined, and the current status of VBA technology is reviewed. In particular, attention is given to the VBA design fundamentals and the performance characteristics of several state-of-the-art VBA models. Finally, prospects for the future development of VBAs and the effect of VBA technology on the inertial navigation industry are discussed.

  11. Technological evolution of petroleum exploration and production. Evolution of Spanish Legislation; Tendencias en la investigacion y explotacion de hidrocarburos. Evolucion de la legislacion espanola

    Energy Technology Data Exchange (ETDEWEB)

    Diaz Fernandez, J. L. [Fundacion REPSOL. Madrid (Spain)

    1998-12-31

    This study begins by briefly review of the technological evolution of petroleum exploration and production. Followed by an analysis of the evolution of reserves, production and prices of oil and natural gas, and a comment on the evolution of Spanish legislation regarding exploration and production of hydrocarbons, to conclude with the analysis of the results obtained through each of the different periods. (Author)

  12. 28 June 2012 - Members of the European Brain Council led by President Mary Baker visiting the LHC tunnel at Point 5 with Technology Department Group Leader L. Bottura and CMS experimental area with Run Coordinator M. Chamizo-Llatas.

    CERN Multimedia

    Jean-Claude Gadmer

    2012-01-01

    28 June 2012 - Members of the European Brain Council led by President Mary Baker visiting the LHC tunnel at Point 5 with Technology Department Group Leader L. Bottura and CMS experimental area with Run Coordinator M. Chamizo-Llatas.

  13. Advanced technologies for plant cell wall evolution and diversity

    DEFF Research Database (Denmark)

    Fangel, Jonatan Ulrik

    Plant cell walls consist of polysaccharides, glycoproteins and phenolic polymers interlinked together in a highly complex network. The detailed analysis of cell walls is challenging because of their inherent complexity and heterogeneity. Also, complex carbohydrates, unlike proteins and nucleotide...... angiosperms. This analysis has enabled cell wall diversity to be placed in a phylogenetic context, and, when integrated with transcriptomic and genomic analysis has contributed to our understanding of important aspects of plant evolution....

  14. The evolution of medical technology: lessons from the Burgess Shale.

    Science.gov (United States)

    Green, S A

    2001-04-01

    Many forthcoming medical advances-growth factors, tissue engineering, gene therapy, attachable prosthetic limbs, and implantable computers--are so new that as yet there is no clinical experience with them. Each therapeutic technique will evolve in an environment containing few guideposts to help judge its efficacy and safety. Recent developments in evolution theory (based on an analysis of Cambrian fossils in Canada's Burgess Shale quarry) suggest that evolution passes, at times, through innovative cycles of progress--when diversification of design leads to perfection of form--with the concomitant production of many unsuccessful models. The evolution of the total knee replacement is a perfect example of the process, because many of the early devices have proven to be dismal failures. However, modern knee replacements would not have been developed without them. Because the risk of unforeseen complications associated with new medical products cannot be discerned in advance, each patient-consumer should have the opportunity to intelligently weigh an innovative product's risk potential against its possible benefit. The proposal made here, for a temporary New Product status for new drugs and devices after a product is cleared by the Food and Drug Administration for general marketing, provides a mechanism for making such decisions.

  15. Evolution of health technology assessment: best practices of the pan-Canadian Oncology Drug Review

    Directory of Open Access Journals (Sweden)

    Rocchi A

    2015-06-01

    Full Text Available Angela Rocchi,1 Isabelle Chabot,2 Judith Glennie3 1Athena Research Inc., Burlington, ON, 2EvAccess Inc., Vaudreuil-Dorion, QC, 3JL Glennie Consulting Inc., Aurora, ON, Canada Background: In 2007, Canada chose to develop a separate and distinct path for oncology drug health technology assessment (HTA. In 2013, the decision was made to transfer the pan-Canadian Oncology Drug Review (pCODR to the Canadian Agency for Drugs and Technologies in Health (CADTH, to align the pCODR and CADTH Common Drug Review processes while building on the best practices of both. The objective of this research was to conduct an examination of the best practices established by the pCODR. Methods: A qualitative research approach was taken to assess the policies, processes, and practices of the pCODR, based on internationally accepted best practice “principles” in HTA, with a particular focus on stakeholder engagement. Publicly available information regarding the approach of the pCODR was used to gauge the agency's performance against these principles. In addition, stakeholder observations and real-world experiences were gathered through key informant interviews to be inclusive of perspectives from patient advocacy groups, provincial and/or cancer agency decision-makers, community and academic oncologists, industry, expert committee members, and health economists. Results: This analysis indicated that, through the pCODR, oncology stakeholders have had a voice in and have come to trust the quality and relevance of oncology HTA as a vital tool to ensure the best decisions for Canadians with cancer and their health care system. It could be expected that adoption of the principles and processes of the pCODR would bring a similar level of engagement and trust to other HTA organizations in Canada and elsewhere. Conclusion: The results of this research led to recommendations for improvement and potential extrapolation of these best practices to other HTA organizations

  16. Marketing-mix and technology: evolution and proactive development

    Directory of Open Access Journals (Sweden)

    Oberemok Svetlana

    2015-10-01

    Full Text Available In order to survive the marketing subjects have to be able to adapt their business-processes to the changing environmental conditions. Those who will correctly predict the direction of the economic vector and will apply adequate and proactive tools and marketing technologies will achieve the greatest success. The article presents the results of the analysis of the leading specialists in the field of marketing and management ideas concerning the transformation of the existing tools and marketing technologies and appearing of the new ones.

  17. Evolution path of MWS technologies: RF, IR, and UV

    Science.gov (United States)

    Tidhar, Gil; Schlisselberg, Raanan

    2005-05-01

    In recent years some major technological developments in the fields of electro-optics and computer H/W took place, which call for reconsideration of the development paths for missile warning systems (MWS). In this work, we provide a review of the technological developments, and then suggest a framework for the following issues: (a) Prioritization of requirements for MWS, (b) Selection of best candidate technologies for next-generation MWS, (c) Establishing a generic parameter sensitivity model for MWS performance, with which we could quantify the effects of different design choices on system-level performance. Our work shows that (a) Infrared optical H/W remains the leading technology for MWS applications, (b) 3rd generation infrared imaging H/W will make a significant impact on MWS performance, compared with 2nd generation based IR-MWS system's performance. (c) Dual band infrared sensor FPAs now under development will further improve performance, yet the improvement will be offset by the lack of some of the more important features of the 3rd generation imagers-very high resolution and frame rate (d) A combination of 3rd generation and dual band IR imaging, when it becomes available, will provide yet another significant improvement.

  18. School Librarians as Technology Leaders: An Evolution in Practice

    Science.gov (United States)

    Wine, Lois D.

    2016-01-01

    The role of school librarians has a history of radical change. School librarians adapted to take on responsibility for technology and audio-visual materials that were introduced in schools in earlier eras. With the advent of the Information Age in the middle of the 20th century and the subsequent development of personal computers and the Internet,…

  19. The Evolution of Global Positioning System (GPS) Technology.

    Science.gov (United States)

    Kumar, Sameer; Moore, Kevin B.

    2002-01-01

    Describes technological advances in the Global Positioning System (GPS), which is also known as the NAVSTAR GPS satellite constellation program developed in 1937, and changes in the nature of our world by GPS in the areas of agriculture, health, military, transportation, environment, wildlife biology, surveying and mapping, space applications, and…

  20. Mapping the (R-)Evolution of Technological Fields

    DEFF Research Database (Denmark)

    Jurowetzki, Roman; Hain, Daniel S.

    2014-01-01

    The aim of this paper was to provide a framework and novel methodology geared towards mapping technological change in complex interdependent systems by using large amounts of unstructured data from various recent on- and offline sources. Combining techniques from the fields of natural language pr...

  1. Football on television: technological evolution and entertainment language

    Directory of Open Access Journals (Sweden)

    Igor José Siquieri Savenhago

    2011-04-01

    Full Text Available The first broadcast of a World Cup footballon television, to Brazil was in 1970, via Embratel. Before that, the people followed the games of the Brazilian team on the radio. Gradually, the owners of television networks realized that football could generate good financial results, with the exposing of advertisements during the broadcasts, similar to what was already done on the radio. Thus, the television, focused on the growth of audience and number of advertisers, covered football with a language of entertainment. The narration of the matches, in which the figure of the narrator is more like that of an entertainer, and improvement of the transmission technologies that improve the image quality every day, take away from football the characteristic of being just a sport to occupy the place of an entertainment. In this context, the sport becomes an article of purchase and sale. The purpose of this study is to demonstrate how this entertainment language was made up on Brazilian television, based on the broadcast sports, especially football, and like the television, which represented a technological leapin the country over the radio, assumed of the sport, country’s most popular as a commodity, interfering with the dynamics of Brazilian society. Finally, an attempt to understand how the researches that allow a technological development change behaviors and vice versa, that is, how the demands of society lead to a race to develop new technologies.

  2. An SAO-based approach to technology evolution analysis using patent information: Case study—graphene sensors

    Institute of Scientific and Technical Information of China (English)

    Zhengyin; HU; Shu; FANG; Ling; WEI; Yi; WEN; Xian; ZHANG; Min; WANG

    2015-01-01

    Purpose: This paper introduces an approach to technology evolution analysis using patent information based on Subject-Action-Object(SAO) structures.Design/methodology/approach: First, SAO structures were extracted from patent documents and were cleaned. Second, several dimension-reduction techniques were used to generate technology topics. Then, the hierarchical relationships between technology topics were calculated based on patent clustering. Finally, technology evolution maps were drawn by adding a timeline.Findings: This approach can reveal technology evolution processes from multiple perspectives than other approaches.Research limitations: The semantic annotation of an SAO type is not very accurate and the semantic types of technology topics need to be enriched.Practical implications: The approach can be applied to draw technology evolution maps using different types of technology topics such as problem or solution.Originality/value: This approach offers an analytical dimension and more details than existing techniques, and it helps identify fundamental and emerging technologies more accurately and comprehensively.

  3. Advanced technologies for plant cell wall evolution and diversity

    DEFF Research Database (Denmark)

    Fangel, Jonatan Ulrik

    Plant cell walls consist of polysaccharides, glycoproteins and phenolic polymers interlinked together in a highly complex network. The detailed analysis of cell walls is challenging because of their inherent complexity and heterogeneity. Also, complex carbohydrates, unlike proteins and nucleotides...... probes (monoclonal antibodies mAbs and carbohydrate binding modules, CBMs) to rapidly profile polysaccharides across a sample set. During my PhD I have further developed the CoMPP technique and used it for cell wall analysis within the context of a variety of applied and fundamental projects. The data...... produced has provided new insight into cell wall evolution and biosynthesis and has contributed to the commercial development of cell wall materials. A major focus of the work has been the wide scale sampling of cell wall diversity across the plant kingdom, from unicellular algae to highly evolved...

  4. Evolution of prefabricated technologies applied to building schools

    OpenAIRE

    Pons, Oriol

    2010-01-01

    In the past ten years, a lot of school buildings have been built using prefabricated systems all over Spain. For example, more than 200 schools have been successfully industrialized since 2002 in Catalonia. These are modern schools that have been recognized for: their well designed architecture, their respectful relationship with their environs, their education spaces… This article aims to analyze these centers, along with the interesting technologies used to build them. This text is based on...

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

    Science.gov (United States)

    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

  6. A Cycle Model of Co-evolution between Emerging Technology and Firm’s Capabilities Based on Case Study

    Institute of Scientific and Technical Information of China (English)

    Wang; Min; Li; Limiao; Yin; Lu

    2011-01-01

    This study explores the mechanism on the co-evolution between emerging technology and capability.Our research focus is how the firms capabilities affect the evolution of emerging technology through strategy.Based on the theoretical analysis and case study,this paper builds a theoretical framework:firms capability is classified into static capability and dynamic capability,and the evolution of emerging technology is summarized by a cycle model.Further,strategy is looked as a mediated variable.The conclusion is that the static capability affects the emerging technology evolution through strategy implement,and the dynamic capability affects the evolution through strategy change.In both situations,organization learning is a key capability to the evolution of emerging technology.

  7. A pharmacist-led information technology intervention for medication errors (PINCER): a multicentre, cluster randomised, controlled trial and cost-effectiveness analysis.

    Science.gov (United States)

    Avery, Anthony J; Rodgers, Sarah; Cantrill, Judith A; Armstrong, Sarah; Cresswell, Kathrin; Eden, Martin; Elliott, Rachel A; Howard, Rachel; Kendrick, Denise; Morris, Caroline J; Prescott, Robin J; Swanwick, Glen; Franklin, Matthew; Putman, Koen; Boyd, Matthew; Sheikh, Aziz

    2012-04-07

    Medication errors are common in primary care and are associated with considerable risk of patient harm. We tested whether a pharmacist-led, information technology-based intervention was more effective than simple feedback in reducing the number of patients at risk of measures related to hazardous prescribing and inadequate blood-test monitoring of medicines 6 months after the intervention. In this pragmatic, cluster randomised trial general practices in the UK were stratified by research site and list size, and randomly assigned by a web-based randomisation service in block sizes of two or four to one of two groups. The practices were allocated to either computer-generated simple feedback for at-risk patients (control) or a pharmacist-led information technology intervention (PINCER), composed of feedback, educational outreach, and dedicated support. The allocation was masked to researchers and statisticians involved in processing and analysing the data. The allocation was not masked to general practices, pharmacists, patients, or researchers who visited practices to extract data. [corrected]. Primary outcomes were the proportions of patients at 6 months after the intervention who had had any of three clinically important errors: non-selective non-steroidal anti-inflammatory drugs (NSAIDs) prescribed to those with a history of peptic ulcer without co-prescription of a proton-pump inhibitor; β blockers prescribed to those with a history of asthma; long-term prescription of angiotensin converting enzyme (ACE) inhibitor or loop diuretics to those 75 years or older without assessment of urea and electrolytes in the preceding 15 months. The cost per error avoided was estimated by incremental cost-effectiveness analysis. This study is registered with Controlled-Trials.com, number ISRCTN21785299. 72 general practices with a combined list size of 480,942 patients were randomised. At 6 months' follow-up, patients in the PINCER group were significantly less likely to have

  8. Scaling a Technology-Based Innovation: Windows on the Evolution of Mathematics Teachers' Practices

    Science.gov (United States)

    Clark-Wilson, A.; Hoyles, C.; Noss, R.; Vahey, P.; Roschelle, J.

    2015-01-01

    This paper reports research on effects on teachers' classroom practices resulting from their engagement in sustained professional development and classroom teaching of a resource that embeds carefully designed dynamic technology within middle school mathematics (11-14 years). The research investigated the self-reported evolution of teachers'…

  9. Radio frequency for particle accelerators: evolution and anatomy of a technology

    CERN Document Server

    Vretenar, M

    2011-01-01

    This introductory lecture outlines the impressive progress of radio frequency technology, from the first table-top equipment to the present gigantic installations. The outcome of 83 years of evolution is subsequently submitted to an anatomical analysis, which allows identifying the main components of a modern RF system and their interrelations.

  10. 基于CPV技术的LED路灯聚光器的研究%Research of LED street lamp condenser based on CPV technology

    Institute of Scientific and Technical Information of China (English)

    王志斌; 解莎莎; 王忠东; 张跃宾; 郝阳

    2012-01-01

    Based on the LED street light solar panel of 120W high-power, the photoelectric conversion efficiency of solar cells is improved by concentrator photovoltaic technology and optical lens (condenser). It can increase the intensity of light by focused action, and reduce the solar light area effectively. So the amount of used material and the cost of solar cells are reduced greatly. Through the TracePro simulation, a kind of optical software, its feasibility is proved.%以120W大功率LED路灯太阳能电池板为研究对象,通过聚光光伏技术,利用光学透镜(聚光器)提高太阳能电池的光电转换效率.利用聚焦作用增大光照密度,有效地降低了太阳能光照面积,极大地减少了光电材料的使用量,大幅度降低了太阳能电池的成本.通过光学仿真软件TracePro进行仿真,验证了其可行性.

  11. Evolution of the sapphire industry: Rubicon Technology and Gavish

    Science.gov (United States)

    Harris, Daniel C.

    2009-05-01

    A. Verneuil developed flame fusion to grow sapphire and ruby on a commercial scale around 1890. Flame fusion was further perfected by Popov in the Soviet Union in the 1930s and by Linde Air Products Co. in the U.S. during World War II. Union Carbide Corp., the successor to Linde, developed Czochralski crystal growth for sapphire laser materials in the 1960s. Stepanov in the Soviet Union published his sapphire growth method in 1959. Edge-Defined Film-Fed Growth (EFG), which is similar to the Stepanov method, was developed by H. Labelle in the U. S. in the 1960s and 1970s. The Heat Exchanger Method (HEM), invented by F. Schmid and D. Viechnicki in 1967 was commercialized in the 1970s. Gradient solidification was invented in Israel in the 1970s by J. Makovsky. The Horizontal Directional Solidification Method (HDSM) proposed by Kh. S. Bagdasorov in the Soviet Union in the 1960s was further developed at the Institute for Single Crystals in Ukraine. Kyropoulos growth of sapphire, known as GOI crystal growth in the Soviet Union, was developed by M. Musatov at the State Optical Institute in St. Petersburg in the 1970s and 1980s. At the Institute for Single Crystals in Ukraine, E. Dobrovinskaya characterized Verneuil, Czochralsky, Bagdasarov, and GOI sapphire. In 1995, she emigrated to the United States and joined S&R Rubicon, founded near Chicago by R. Mogilevsky initially to import sapphire and ruby. Mogilevsky began producing sapphire by the Kyropoulos method in 1999. In 2000 the company name was changed to Rubicon Technology. Today, Dobrovinskaya is Chief Scientist and Rubicon produces high quality Kyropoulos sapphire substrates for solid-state lighting. In 1995, H. Branover of Ben Gurion University and a sole investor founded Gavish, which is Hebrew for "crystal." They invited another veteran of the Ukrainian Institute for Single Crystals, V. Pishchik, to become Chief Scientist. Under Pishchik's technical leadership and J. Sragowicz's business leadership, Gavish now

  12. The evolution of high-technology in China after 1978: Towards technological entrepreneurship

    NARCIS (Netherlands)

    M.J. Greeven (Mark)

    2004-01-01

    textabstractThe purpose of this paper is to describe the development of China’s science and technology, their related institutions and use in the business world since the reforms started in 1978. Special attention will be given to the re-integration of high-technology into the private sector and th

  13. Quality, technology and outcomes: evolution and evaluation of new treatments and/or new technology.

    Science.gov (United States)

    Fraass, Benedick A; Moran, Jean M

    2012-01-01

    The pace of technological innovation and adoption continues to increase each year, and the field of Radiation Oncology struggles to react appropriately to the changes and potential improvements in treatment which hopefully will result from this innovation. The standard methods used in the past to test new technology and treatment techniques are often no longer appropriate for this fast-changing environment. This paper uses examples from radiotherapy technological developments over the last decades to illustrate issues which need to be solved in order to study and evaluate potential advances, and then describes several improved ways to study new techniques and technology. Design of appropriate studies can help us improve patient care while at the same time documenting which new clinical strategies, enabled by new technology, lead to improved patient outcomes.

  14. A paleo-aerodynamic exploration of the evolution of nature's flyers, man's aircraft, and the needs and options for future technology innovations

    Science.gov (United States)

    Kulfan, Brenda M.

    2009-03-01

    Insights and observations of fascinating aspects of birds, bugs and flying seeds, of inspired aerodynamic concepts, and visions of past, present and future aircraft developments are presented. The evolution of nature's flyers, will be compared with the corresponding evolution of commercial aircraft. We will explore similarities between nature's creations and man's inventions. Many critical areas requiring future significant technology based solutions remain. With the advent of UAVs and MAVs, the gap between "possible" and "actual" is again very large. Allometric scaling procedures will be used to explore size implications on limitations and performance capabilities of nature's creations. Biologically related technology development concepts including: bionics, biomimicry, neo-bionic, pseudo-mimicry, cybernetic and non-bionic approaches will be discussed and illustrated with numerous examples. Technology development strategies will be discussed along with the pros and cons for each. Future technology developments should include a synergistic coupling of "discovery driven", "product led" and "technology acceleration" strategies. The objective of this presentation is to inspire the creative nature existing within all of us. This is a summary all text version of the complete report with the same title that report includes approximately 80 figures, photos and charts and much more information.

  15. Cost effectiveness of a pharmacist-led information technology intervention for reducing rates of clinically important errors in medicines management in general practices (PINCER).

    Science.gov (United States)

    Elliott, Rachel A; Putman, Koen D; Franklin, Matthew; Annemans, Lieven; Verhaeghe, Nick; Eden, Martin; Hayre, Jasdeep; Rodgers, Sarah; Sheikh, Aziz; Avery, Anthony J

    2014-06-01

    We recently showed that a pharmacist-led information technology-based intervention (PINCER) was significantly more effective in reducing medication errors in general practices than providing simple feedback on errors, with cost per error avoided at £79 (US$131). We aimed to estimate cost effectiveness of the PINCER intervention by combining effectiveness in error reduction and intervention costs with the effect of the individual errors on patient outcomes and healthcare costs, to estimate the effect on costs and QALYs. We developed Markov models for each of six medication errors targeted by PINCER. Clinical event probability, treatment pathway, resource use and costs were extracted from literature and costing tariffs. A composite probabilistic model combined patient-level error models with practice-level error rates and intervention costs from the trial. Cost per extra QALY and cost-effectiveness acceptability curves were generated from the perspective of NHS England, with a 5-year time horizon. The PINCER intervention generated £2,679 less cost and 0.81 more QALYs per practice [incremental cost-effectiveness ratio (ICER): -£3,037 per QALY] in the deterministic analysis. In the probabilistic analysis, PINCER generated 0.001 extra QALYs per practice compared with simple feedback, at £4.20 less per practice. Despite this extremely small set of differences in costs and outcomes, PINCER dominated simple feedback with a mean ICER of -£3,936 (standard error £2,970). At a ceiling 'willingness-to-pay' of £20,000/QALY, PINCER reaches 59 % probability of being cost effective. PINCER produced marginal health gain at slightly reduced overall cost. Results are uncertain due to the poor quality of data to inform the effect of avoiding errors.

  16. Origin of diderm (Gram-negative) bacteria: antibiotic selection pressure rather than endosymbiosis likely led to the evolution of bacterial cells with two membranes.

    Science.gov (United States)

    Gupta, Radhey S

    2011-08-01

    The prokaryotic organisms can be divided into two main groups depending upon whether their cell envelopes contain one membrane (monoderms) or two membranes (diderms). It is important to understand how these and other variations that are observed in the cell envelopes of prokaryotic organisms have originated. In 2009, James Lake proposed that cells with two membranes (primarily Gram-negative bacteria) originated from an ancient endosymbiotic event involving an Actinobacteria and a Clostridia (Lake 2009). However, this Perspective argues that this proposal is based on a number of incorrect assumptions and the data presented in support of this model are also of questionable nature. Thus, there is no reliable evidence to support the endosymbiotic origin of double membrane bacteria. In contrast, many observations suggest that antibiotic selection pressure was an important selective force in prokaryotic evolution and that it likely played a central role in the evolution of diderm (Gram-negative) bacteria. Some bacterial phyla, such as Deinococcus-Thermus, which lack lipopolysaccharide (LPS) and yet contain some characteristics of the diderm bacteria, are postulated as evolutionary intermediates (simple diderms) in the transition between the monoderm bacterial taxa and the bacterial groups that have the archetypal LPS-containing outer cell membrane found in Gram-negative bacteria. It is possible to distinguish the two stages in the evolution of diderm-LPS cells (viz. monoderm bacteria → simple diderms lacking LPS → LPS containing archetypal diderm bacteria) by means of conserved inserts in the Hsp70 and Hsp60 proteins. The insert in the Hsp60 protein also distinguishes the traditional Gram-negative diderm bacterial phyla from atypical taxa of diderm bacteria (viz. Negativicutes, Fusobacteria, Synergistetes and Elusimicrobia). The Gram-negative bacterial phyla with an LPS-diderm cell envelope, as defined by the presence of the Hsp60 insert, are indicated to form a

  17. Constructal law of design and evolution: Physics, biology, technology, and society

    Science.gov (United States)

    Bejan, Adrian; Lorente, Sylvie

    2013-04-01

    This is a review of the theoretical and applied progress made based on the Constructal law of design and evolution in nature, with emphasis on the last decade. The Constructal law is the law of physics that accounts for the natural tendency of all flow systems (animate and inanimate) to change into configurations that offer progressively greater flow access over time. The progress made with the Constructal law covers the broadest range of science, from heat and fluid flow and geophysics, to animal design, technology evolution, and social organization (economics, government). This review presents the state of this fast growing field, and draws attention to newly opened directions for original research. The Constructal law places the concepts of life, design, and evolution in physics.

  18. Perspectives on the evolution of mobile (mHealth) technologies and application to rehabilitation.

    Science.gov (United States)

    Dicianno, Brad E; Parmanto, Bambang; Fairman, Andrea D; Crytzer, Theresa M; Yu, Daihua X; Pramana, Gede; Coughenour, Derek; Petrazzi, Alan A

    2015-03-01

    Individuals with chronic conditions and disabilities who are vulnerable to secondary complications often require complex habilitative and rehabilitative services to prevent and treat these complications. This perspective article reviews the evolution of mHealth technologies and presents insights as to how this evolution informed our development of a novel mHealth system, iMHere (interactive mobile health and rehabilitation), and other technologies, including those used by the Veterans Administration. This article will explain the novel applications of mHealth for rehabilitation and specifically physical therapy. Perspectives on the roles of rehabilitation professionals in the delivery of health care using mHealth systems are included. Challenges to mHealth, including regulatory and funding issues, are discussed. This article also describes how mHealth can be used to improve patient satisfaction and delivery of care and to promote health and wellness.

  19. Introducing time delay in the evolution of new technology: the case study of nanotechnology

    Science.gov (United States)

    Georgalis, Evangelos E.; Aifantis, Elias C.

    2013-12-01

    Starting with Feynman's "There's Plenty of Room at the Bottom" prophetic lecture at Caltech in the 1960s, the term "nanotechnology" was first coined in the scientific literature in the 1980s. This was followed by the unprecedented growth in the corresponding scientific field in 2000 due to the financial incentive provided by President Clinton in the US, followed up by similar efforts in Europe, Japan, China and Russia. Today, nanotechnology has become a driving force for economic development, with applications in all fields of engineering, information technology, transport and energy, as well as biology and medicine. Thus, it is important to forecast its future growth and evolution on the basis of two different criteria: (1) the government and private capital invested in related activities, and (2) the number of scientific publications and popular articles dedicated to this field. This article aims to extract forecasts on the evolution of nanotechnology, using the standard logistic equation that result in familiar sigmoid curves, as well as to explore the effect of time delay on its evolution. Time delay is commonly known from previous biological and ecological models, in which time lag is either already known or can be experimentally measured. In contrast, in the case of a new technology, we must first define the method for determining time delay and then interpret its existence and role. Then we describe the implications that time delay may have on the stability of the sigmoidal behavior of nanotechnology evolution and on the related oscillations that may appear.

  20. Employee Involvement, Technology, and Evolution in Job Skills: A Task-Based Analysis

    OpenAIRE

    Francis Green

    2012-01-01

    The author investigates the evolution of job skill distribution using task data derived from the U.K. Skills Surveys of 1997, 2001, and 2006, and the 1992 Employment Survey in Britain. He determines the extent to which employee involvement in the workplace and computer technologies promote the use of higher order cognitive and interactive skills. He finds that literacy, other communication tasks, and self-planning skills have grown especially fast. Numerical and problem-solving skills have al...

  1. An innovative approach to predict technology evolution for the desoldering of printed circuit boards: A perspective from China and America.

    Science.gov (United States)

    Wang, Chen; Zhao, Wu; Wang, Jie; Chen, Ling; Luo, Chun-Jing

    2016-06-01

    The printed circuit boards basis of electronic equipment have seen a rapid growth in recent years and played a significant role in modern life. Nowadays, the fact that electronic devices upgrade quickly necessitates a proper management of waste printed circuit boards. Non-destructive desoldering of waste printed circuit boards becomes the first and the most crucial step towards recycling electronic components. Owing to the diversity of materials and components, the separation process is difficult, which results in complex and expensive recovery of precious materials and electronic components from waste printed circuit boards. To cope with this problem, we proposed an innovative approach integrating Theory of Inventive Problem Solving (TRIZ) evolution theory and technology maturity mapping system to forecast the evolution trends of desoldering technology of waste printed circuit boards. This approach can be applied to analyse the technology evolution, as well as desoldering technology evolution, then research and development strategy and evolution laws can be recommended. As an example, the maturity of desoldering technology is analysed with a technology maturity mapping system model. What is more, desoldering methods in different stages are analysed and compared. According to the analysis, the technological evolution trends are predicted to be 'the law of energy conductivity' and 'increasing the degree of idealisation'. And the potential technology and evolutionary state of waste printed circuit boards are predicted, offering reference for future waste printed circuit boards recycling.

  2. Analysis of Huayingshan tunnel LED lighting technology application and energy saving effect%华蓥山隧道LED照明技术应用及节能效果分析

    Institute of Scientific and Technical Information of China (English)

    叶杰文

    2013-01-01

    With the continuous development of LED technology, power and lighting effects lighting im-provement, LED has been applied and popularized in the tunnel lighting. This paper introduces the charac-teristics of new LED light source, and to compare the LED lamp and high pressure sodium lamp. Com-bined with the implementation of Sichuan Province Huayingshan tunnel LED lighting project, the energy-saving effect and benefit of tunnel using LED lighting fixtures are analyzed.%随着LED技术的不断发展,照明功率与照明功效的提高,LED在隧道照明中已经得到应用和推广。本文介绍了LED新光源的特点并对LED灯具和传统高压钠灯进行比较。同时结合四川省华蓥山隧道LED照明工程的实施情况,对隧道使用LED照明灯具的节能效果及效益进行了分析。

  3. New media technology and youth: trends in the evolution of new media.

    Science.gov (United States)

    Biocca, F

    2000-08-01

    An information environment is emerging from the simultaneous, rapid, and interconnected evolution of transmission systems, interfaces, and content quantity, quality, and structure. It will be easy to underestimate the collective impact of the sum of these changes on how young people communicate and absorb information. Ultimately, it will be more important to understand how these technologies will facilitate, amplify, or alter the cognitive processes and/or social behavior of the Internet generation. The article analyzes the impact of the following trends on media use and cognition among youthful users: * Information expansion and overload: Accessible networked information will continue to grow at a rapid pace for at least the next 10-20 years. * Rapid increase in interface diffusion: The number of access points into the Internet is expanding in number, variety, and mobility. * Evolution toward more embodied computing: Interfaces are evolving to use more of the sensorimotor system to transfer information to and from the user. * The evolution of more intelligent sensors to interpret use behavior and intentions. * Evolution toward anthropomorphic agent techniques: Computers are evolving to use more social and interpersonal communication techniques to interact with the user.

  4. Implementation of a Low-Cost Automated LED Photometer for Enzymatic Reaction Detection to Teach Basic Bioelectronics Technologies in Vocational High Schools

    Science.gov (United States)

    Chen, Huai-Yi; Nieh, Hwa-Ming; Yang, Ming-Feng; Chou, Yu-Kung; Chung, Jui-Hsu; Liou, Je-Wen

    2016-01-01

    This study proposes a home-assembled, low-cost blue light-emitting diode (LED) photometer that uses simple and low-cost hardware and software, costing about US $150. This 425-nm wavelength photometer is controlled by an 89C51 microcontroller chip. Glucose concentration detection experiments involving enzyme coupling reactions were carried out to…

  5. Using Multidisciplinary Focus Groups to Inform the Development of mI SMART: A Nurse-Led Technology Intervention for Multiple Chronic Conditions

    OpenAIRE

    Mallow, Jennifer A; Laurie A. Theeke; Elliott Theeke; Mallow, Brian K.

    2016-01-01

    Used as integrated tools, technology may improve the ability of healthcare providers to improve access and outcomes of care. Little is known about healthcare teams' preferences in using such technology. This paper reports the findings from focus groups aimed at evaluating a newly developed primary care technology platform. Focus groups were completed in academic, outpatient, and community settings. Focus groups were attended by 37 individuals. The participants included professionals from mult...

  6. On the Relationship between the Evolution of Technological Firms and Their Knowledge Development Regimes

    Institute of Scientific and Technical Information of China (English)

    BRINK Johan; MCKELVEY Maureen

    2006-01-01

    Differences in knowledge regimes and growth dynamics amongst four ideal types of knowledge based firms are analyzed. Two aspects of technological knowledge, technological opportunity and appropriability are traditionally seen as vital to understand the incentives for research and development activities in firms. However, they do not fully define the technology regimes, when one asks how the knowledge based firm competes. Therefore, the dynamic nature of firm capabilities and knowledge development in terms of expansion and in terms of deepening are also discussed. These two additional aspects of knowledge implies that even if all firms in an industry can be considered to be knowledge intensive these firms do also differ. Using cases of entrepreneurial start-up firms in Sweden, we illustrate whether our conceptual ideas of knowledge development help us understand the diversity and contradictions of firm evolution. Our finding is that firm evolution and capability development is dependent upon both the potential for expanding knowledge, such as by innovations, and by deepening the understanding within established knowledge, such as by learning. This implies that the shaping of a science based industry must be seen in relation both to the value of current knowledge and capabilities together with the sometimes only limited and temporarily advantages of radical innovations.

  7. US long distance fiber optic networks: Technology, evolution and advanced concepts. Volume 1: Executive summary

    Science.gov (United States)

    1986-01-01

    Over the past two decades, fiber optics has emerged as a highly practical and cost-efficient communications technology. Its competitiveness vis-a-vis other transmission media, especially satellite, has become a critical question. This report studies the likely evolution and application of fiber optic networks in the United States to the end of the century. The outlook for the technology of fiber systems is assessed and forecast, scenarios of the evolution of fiber optic network development are constructed, and costs to provide service are determined and examined parametrically as a function of network size and traffic carried. Volume 1 consists of the Executive Summary. Volume 2 focuses on fiber optic technology and long distance fiber optic networks. Volume 3 develops a traffic and financial model of a nationwide long distance transmission network. Among the study's most important conclusions are: revenue requirements per circuit for LATA-to-LATA fiber optic links are less than one cent per call minute; multiplex equipment, which is likely to be required in any competing system, is the largest contributor to circuit costs; the potential capacity of fiber optic cable is very large and as yet undefined; and fiber optic transmission combined with other network optimization schemes can lead to even lower costs than those identified in this study.

  8. LED-roulette: LED's vervangen balletje

    NARCIS (Netherlands)

    Goossens, P.

    2007-01-01

    Iedereen waagt wel eens een gokje, in een loterij of misschien ook in een casino. Wie droomt er immers niet van om op een gemakkelijke manier rijk te worden? Met de hier beschreven LED-roulette valt weliswaar weinig te winnen, maar het is wel een uitstekende manier om het roulettespel thuis te beoef

  9. LED-roulette: LED's vervangen balletje

    NARCIS (Netherlands)

    Goossens, P.

    2007-01-01

    Iedereen waagt wel eens een gokje, in een loterij of misschien ook in een casino. Wie droomt er immers niet van om op een gemakkelijke manier rijk te worden? Met de hier beschreven LED-roulette valt weliswaar weinig te winnen, maar het is wel een uitstekende manier om het roulettespel thuis te

  10. Semiconductor lasers and herterojunction leds

    CERN Document Server

    Kressel, Henry

    2012-01-01

    Semiconductor Lasers and Heterojunction LEDs presents an introduction to the subject of semiconductor lasers and heterojunction LEDs. The book reviews relevant basic solid-state and electromagnetic principles; the relevant concepts in solid state physics; and the p-n junctions and heterojunctions. The text also describes stimulated emission and gain; the relevant concepts in electromagnetic field theory; and the modes in laser structures. The relation between electrical and optical properties of laser diodes; epitaxial technology; binary III-V compounds; and diode fabrication are also consider

  11. Research on the Cooling Technology for the High-Power LED Bay Lamp%LED工矿灯散热技术研究

    Institute of Scientific and Technical Information of China (English)

    罗婉霞

    2013-01-01

    为满足LED工矿灯的散热需求,设计了一款新型烧结热管式的散热模组,对该模组进行了应用于不同环境温度条件的数值模拟研究,并与实验数据进行了比较分析。结果发现,数值模拟与实验所得结果偏差在4.01%以内。这表明,所设计散热方案能够很好地满足该种LED工矿灯在不同环境下的散热需求,该数值模拟方法能够为今后设计同类产品提供设计理论依据。%To meet the cooling requirement of the high-power LED bay lamp, a novel cooling module was designed. Furthermore, the numerical simulation research on the cooling module used for LED bay lamp was carried out,and the simulation result has been compared with the experimental data. The simulation result agrees well with the experimental data,and the relative error is within 4.01%. The result shows that the cooling solution proposed can meets the cooling requirement of the LED high bay designed on the different operating condition.

  12. Package Technology of Silicon-based High-power LEDs with TSV%带有TSV的硅基大功率LED封装技术研究

    Institute of Scientific and Technical Information of China (English)

    师帅; 吕植成; 汪学方; 王飞; 袁娇娇; 方靖

    2013-01-01

    Introduced is the fabrication of silicon base with groove and TSV (through silicon via) for wafer level packaging of white LED.Based on the structure of silicon-based high-power LEDs,the heat transfer model is established and finite element software is employed to simulate and analyze the heat dissipation of this package.Simulation results show that the silicon base packaging meets the temperature requirement of LED chip p-n junction.Combined with semiconductor manufacturing process,the fabrication of the groove and TSV was carried out on the silicon substrate,realizing effective packaging of LED chips.The thermal resistance of silicon substrate measured by T3Ster is 1.068 K/W.Experimental results show that this method is effective for realizing LED chip packaging with low cost,low thermal resistance and high density.%介绍了一种带有凹槽和硅通孔(through silicon via,TSV)的硅基制备以及晶圆级白光LED的封装方法.针对硅基大功率LED的封装结构建立了热传导模型,并通过有限元软件模拟分析了这种封装形式的散热效果.模拟结果显示,硅基封装满足LED芯片p-n结的温度要求.实验结合半导体制造工艺,在硅基板上完成了凹槽和通孔的制造,实现了LED芯片的有效封装.热阻测试仪测得硅基的热阻为1.068 K/W.实验结果证明,这种方法有效实现了低热阻、低成本、高密度的LED芯片封装,是大功率LED封装发展的重要方向.

  13. Cows Desiring to Be Milked? Milking Robots and the Co-Evolution of Ethics and Technology on Dutch Dairy Farms

    NARCIS (Netherlands)

    Driessen, C.P.G.; Heutinck, L.F.M.

    2015-01-01

    Ethical concerns regarding agricultural practices can be found to co-evolve with technological developments. This paper aims to create an understanding of ethics that is helpful in debating technological innovation by studying such a co-evolution process in detail: the development and adoption of th

  14. The Evolution of U.S. e-Learning Policy: A Content Analysis of the National Education Technology Plans

    Science.gov (United States)

    Roumell, Elizabeth Anne; Salajan, Florin Daniel

    2016-01-01

    The purpose of this study was threefold: to expand on existing reviews of 20 years of educational technology policy in the United States, to perform an empirical content analysis of the four National Education Technology Plan (NETP) documents issued by the Department of Education since 1996, and to provide a dialectic analysis of the evolution of…

  15. 基于专利文献的我国LED背光源技术态势分析%Analysis of Chinese LED Backlight Technology Based on Patent Documents

    Institute of Scientific and Technical Information of China (English)

    杨波

    2011-01-01

    Using official web site of Chinese patent database and patent information analysis systems, the paper searches, analyzes and summarizes the related patent data of LED backlight technology. Then from the perspectives of application a mount, key patents and patent holders, the paper analyzes the patents of LED backlight technology. Finally, the paper pro vides reference to the R&D and patent composition of LED backlight technology.%利用国家知识产权局网站上发布的中国专利数据库,采用专利信息分析系统,对LED背光源技术领域的相关专利数据进行检索、分析、归纳,从专利申请总量、重点专利技术和专利持有人等方面对LED背光源技术专利进行分析总结,为国内LED背光源产业技术研发和专利布局提供参考.

  16. The evolution and evaluation of videoconferencing technology for graduate nursing education.

    Science.gov (United States)

    Sackett, Kay Marie; Campbell-Heider, Nancy; Blyth, John B

    2004-01-01

    The Integrated Services Digital Network H.323 (ISDN), which has been in use for the past 20 years often requires a dedicated telephone line and other equipment to implement. Consequently, expansion of ISDN-based videoconferencing requires infrastructure not always accessible in those areas that are most in need of technological connections. New H.323 technology using Internet Protocol H.320 (IP) connectivity can accommodate the use in a variety of videoconferencing software and fill this void as demonstrated by an experiment conducted live at the Syllabus Web '99 conference. When a faculty group were unable to secure ISDN connections to demonstrate their clinical evaluation of Family Nurse Practitioner (FNP) students using videoconferencing technology, an ad hoc group of computer experts, educators, instructional design specialists, and corporate sponsors collaborated to design a multipoint PC-based connection using IP connectivity. This article describes the first application of this technology, the evolution of ISDN and IP systems in nursing education and practice, and suggests appropriate future trends for their utility in nursing.

  17. Application Principle and Technology Progress in Using LightEmitting Diode (LED) Light Sources in Modern Agriculture%LED光源在现代农业的应用原理与技术进展

    Institute of Scientific and Technical Information of China (English)

    杨其长; 徐志刚; 陈弘达; 泮进明; 魏灵玲; 刘文科; 周泓; 刘晓英; 宋昌斌

    2011-01-01

    The application of light-emitting diode (LED) in modern agriculture has been increasingly concerned by countries worldwide with the development of LED technology and the decrease of its cost. LED has many advantages compared with the other electric light sources. First, it has good traits of photoelectric such as small size, longer life, low energy consumption, high luminous efficiency and low heat production. Second, light spectral composition of LED light source can be easily integrated or tailored according to the need of plant. LED light sources can efficiently promote the growth & development, photo-morphogenesism, yield and quality of agricultural organisms. In this paper, application status of LED in agriculture was outlined, potential of LED application was analyzed, and key (actors that limits application of LED in agriculture was pointed out. Finally, future development strategy, orientations and countermeasures of LED application in modern agriculture were discussed.%随着LED技术的发展和制造成本的下降,LED光源在现代农业中的应用越来越受到世界各国的广泛关注.LED不仅具有体积小、寿命长、能耗低、发光效率高、发热低等光电特性优点,而且还能根据农业生物的需要进行光谱的精确配置,促进农业生物的生长发育和光形态建成,从而提高其产量和品质.本文介绍了LED在农业照明领域的应用现状,分析了LED在农业领域的应用潜力,指出了限制农用LED推广应用的关键因素,并提出促进LED在现代农业中应用的发展思路、方向和重点以及对策.

  18. Using Multidisciplinary Focus Groups to Inform the Development of mI SMART: A Nurse-Led Technology Intervention for Multiple Chronic Conditions.

    Science.gov (United States)

    Mallow, Jennifer A; Theeke, Laurie A; Theeke, Elliott; Mallow, Brian K

    2016-01-01

    Used as integrated tools, technology may improve the ability of healthcare providers to improve access and outcomes of care. Little is known about healthcare teams' preferences in using such technology. This paper reports the findings from focus groups aimed at evaluating a newly developed primary care technology platform. Focus groups were completed in academic, outpatient, and community settings. Focus groups were attended by 37 individuals. The participants included professionals from multiple disciplines. Both prescribing (N = 8) and nonprescribing healthcare team members (n = 21) completed the focus groups and survey. The majority were practicing for more than 20 years (44.8%) in an outpatient clinic (62%) for 20-40 hours per week (37.9%). Providers identified perceived obstacles of patient use as ability, willingness, and time. System obstacles were identified as lack of integration, lack of reimbursement, and cost. The positive attributes of the developed system were capability for virtual visits, readability, connectivity, user-friendliness, ability to capture biophysical measures, enhanced patient access, and incorporation of multiple technologies. Providers suggested increasing capability for biophysical and symptom monitoring for more common chronic conditions. Technology interventions have the potential to improve access and outcomes but will not be successful without the input of users.

  19. Using Multidisciplinary Focus Groups to Inform the Development of mI SMART: A Nurse-Led Technology Intervention for Multiple Chronic Conditions

    Directory of Open Access Journals (Sweden)

    Jennifer A. Mallow

    2016-01-01

    Full Text Available Used as integrated tools, technology may improve the ability of healthcare providers to improve access and outcomes of care. Little is known about healthcare teams’ preferences in using such technology. This paper reports the findings from focus groups aimed at evaluating a newly developed primary care technology platform. Focus groups were completed in academic, outpatient, and community settings. Focus groups were attended by 37 individuals. The participants included professionals from multiple disciplines. Both prescribing (N=8 and nonprescribing healthcare team members (n=21 completed the focus groups and survey. The majority were practicing for more than 20 years (44.8% in an outpatient clinic (62% for 20–40 hours per week (37.9%. Providers identified perceived obstacles of patient use as ability, willingness, and time. System obstacles were identified as lack of integration, lack of reimbursement, and cost. The positive attributes of the developed system were capability for virtual visits, readability, connectivity, user-friendliness, ability to capture biophysical measures, enhanced patient access, and incorporation of multiple technologies. Providers suggested increasing capability for biophysical and symptom monitoring for more common chronic conditions. Technology interventions have the potential to improve access and outcomes but will not be successful without the input of users.

  20. Dansk LED - Museumsbelysning

    DEFF Research Database (Denmark)

    Poulsen, Peter Behrensdorff; Dam-Hansen, Carsten; Thorseth, Anders

    Projektet har til formål at anvende dansk forskning inden for optik og lys til at realisere innovative energieffektive LED lyssystemer til museumsbranchen.......Projektet har til formål at anvende dansk forskning inden for optik og lys til at realisere innovative energieffektive LED lyssystemer til museumsbranchen....

  1. 基于Kinect体感识别技术在LED显示屏上的应用%Application of Based on Kinect Body Recognition Technology to LED Display Screen

    Institute of Scientific and Technical Information of China (English)

    李庆

    2014-01-01

    nowadays, the LED display screen has been widely used in the industries of advertising, commercial real estate and etc. However the traditional LED display can be only a single display of scheduled videos, photos and texts, which is difficult to catch people's eyes .Therefore, the interactive LED display is emerging, it can not only change its display content by somatosensory recognition, but also realize human-computer interaction through actions and gestures. This article is to research the application of somatosensory recognition technology based on Kinect in the LED display, which has wide application prospects.%现今,LED显示屏已经广泛的运用在广告及商业地产等行业中。但是传统的LED显示屏只能单一的显示预设好的视频或图片、文字内容,很难抓人眼球。因此,新兴的交互式LED显示屏应运而生,其可以通过体感识别来改变播放内容甚至还能通过动作、手势实现人机交互。本文研究的是基于Kinect体感识别技术在LED显示屏上的应用,具有广阔的实际应用前景。

  2. Implementation and Test of a LED-Based Lamp for a Lighthouse

    Directory of Open Access Journals (Sweden)

    Luca Mercatelli

    2014-01-01

    Full Text Available A novel sustainable source was developed for an existing Italian lighthouse, exploiting the light emitting diode (LED technology and the norms evolution. The research work started with the optical design of the device, while this work concerns the realization, installation, and test of the new LED lamp. The lamp recombines multiple separated LEDs, realizing a quasipunctual localized source. After installation in the lighthouse, specific photometric tests verified that the proposed power-saving source satisfied the illumination requirements of the marine signaling norms. The advantages of the LED-based lamp are reduced energy consumption, enhanced efficiency, longer life, decreased faults, slower aging, and lower maintenance costs. The obtained LED signalling device is more durable and reliable. In the future the application of these power-saving long-life sources could be extended to other maritime signaling devices or to other traffic signs.

  3. 基于ZigBee技术的LED调光控制系统设计%Design of LED Dimming Control System Based on ZigBee Technology

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    针对传统照明系统布线麻烦、可扩展性差、节能效率低等问题,本文将ZigBee无线传感网络和Bluetooth技术结合其起来,设计出一款通过手机智能控制的LED调光系统。以TI公司生产的CC2530为主要硬件平台,运用ZigBee协议栈开发组建自组网系统,ZigBee协调器连接Bluetooth模块,实现在基于Android系统的智能手机上对LED开关、亮度和颜色的控制功能。使用NCL30160作为驱动芯片,可实现数字调光功能。本系统低能耗,人性化管理,具有很好的市场前景。%The traditional lighting system has such problems as complicated wiring, poor extendibility and low power efficiency. For the problems, this paper presents a new intelligent LED dimming control system by combining ZigBee wireless sensor network and Bluetooth techniques. The design uses the CC2530 made by TI Company as the hardware platform and develops an ad hoc network based on the ZigBee protocol. The ZigBee coordinator links Bluetooth module, which realizes the control functions of LED switches, brightness and colors, based on the Android system of the intelligent mobile phones. The NCL30160 is used as the drive chip to realize the digital dimming control. With the strengths of low-power consumption and easy operation, the new system has good market prospects.

  4. Influence of Fluorescent Glue Packaging Technology on the Color Rendering Index of High Power LED%大功率LED荧光胶封装工艺对其显色性能的影响

    Institute of Scientific and Technical Information of China (English)

    钟传鹏

    2011-01-01

    通过大量试验,探索了荧光粉分层封装和荧光粉混合封装的不同荧光胶封装工艺对大功率白光LED显色性能的影响。通过甄选荧光粉、硅胶以及配比,制备出显色指数(CRI)为95的高亮度、低衰减的大功率白光LED。%In this artical,a large number of experiments have been done to explore the influence of different fluorescent glue packaging technology of phosphor layered packaging and phosphor mixed packaging on high-power white LED color rendering.By selecting the phosphor,silicon and mixture ratio,high-power white LED with high brightness and low attenuation is prepared,and the color rendering index(CRI) reaches 95.

  5. Evolution of technology in teaching: Blackboard and beyond in Medical Education.

    Science.gov (United States)

    Muttappallymyalil, Jayakumary; Mendis, Susirith; John, Lisha Jenny; Shanthakumari, Nisha; Sreedharan, Jayadevan; Shaikh, Rizwana B

    2016-10-01

    the passing of knowledge from one generation to another - has been in existence from the earliest times of human civilization. It began in 1801, with a large piece of slate hung on the wall in a school in Scotland to provide information to a large audience at one time. In the US by mid-19th century, every class room had a blackboard to teach students. The modern version of the blackboard is either green or brown board. This was introduced in late 1960s. The whiteboards came into use during the late 1980s. Projected aids have been used since 1420. The various devices used are the epidiascope, slide projector, overhead projector for transparencies and the micro projector. An instrument to project images from a horizontal surface onto a vertical screen was invented in the 1870s. By the 1960s, transparencies were in use in classrooms. The 'Hyalotype', a transparent image of a photograph using actual black and white photographs on a glass slide that could be projected was invented in 1851. By 1916, the German company Agfa started producing colored lantern slides. The first version of PowerPoint was released by Microsoft in the year 1990. Cell phones, palmtops, and handheld computers; tablets, laptops, and media players are included under mobile learning devices. With the evolution of technology, students achieved competence and interested in interactive learning. The education industry has moved from distance learning to e-learning and finally to m-learning as knowledge expanded exponentially and the demand escalated. While using teaching aids with advanced technology, we must not forget the lessons from the past, striking a balance between embracing new methods of teaching and learning while upholding the timeless principles of education. The newer educational technology can be part of a comprehensive system for lifelong education. Use of technology in education has come a long way since the earliest times of human civilization. While embarking on aids with advanced

  6. Evolution of technology in teaching: Blackboard and beyond in Medical Education

    Science.gov (United States)

    Mendis, Susirith; John, Lisha Jenny; Shanthakumari, Nisha; Sreedharan, Jayadevan; Shaikh, Rizwana B

    2016-01-01

    Teaching and learning the passing of knowledge from one generation to another - has been in existence from the earliest times of human civilization. It began in 1801, with a large piece of slate hung on the wall in a school in Scotland to provide information to a large audience at one time. In the US by mid-19th century, every class room had a blackboard to teach students. The modern version of the blackboard is either green or brown board. This was introduced in late 1960s. The whiteboards came into use during the late 1980s. Projected aids have been used since 1420. The various devices used are the epidiascope, slide projector, overhead projector for transparencies and the micro projector. An instrument to project images from a horizontal surface onto a vertical screen was invented in the 1870s. By the 1960s, transparencies were in use in classrooms. The ‘Hyalotype’, a transparent image of a photograph using actual black and white photographs on a glass slide that could be projected was invented in 1851. By 1916, the German company Agfa started producing colored lantern slides. The first version of PowerPoint was released by Microsoft in the year 1990. Cell phones, palmtops, and handheld computers; tablets, laptops, and media players are included under mobile learning devices. With the evolution of technology, students achieved competence and interested in interactive learning. The education industry has moved from distance learning to e-learning and finally to m-learning as knowledge expanded exponentially and the demand escalated. While using teaching aids with advanced technology, we must not forget the lessons from the past, striking a balance between embracing new methods of teaching and learning while upholding the timeless principles of education. The newer educational technology can be part of a comprehensive system for lifelong education. Conclusion: Use of technology in education has come a long way since the earliest times of human civilization

  7. Targeted Prostate Biopsy: Lessons Learned Midst the Evolution of a Disruptive Technology.

    Science.gov (United States)

    Nassiri, Nima; Natarajan, Shyam; Margolis, Daniel J; Marks, Leonard S

    2015-09-01

    Lessons learned during a 6-year experience with more than 1200 patients undergoing targeted prostate biopsy via MRI/ultrasound fusion are reported: (1) the procedure is safe and efficient, requiring some 15-20 minutes in an office setting; (2) MRI is best performed by a radiologist with specialized training, using a transabdominal multiparametric approach and preferably a 3T magnet; (3) grade of MRI suspicion is the most powerful predictor of biopsy results, eg, Grade 5 usually represents cancer; (4) some potentially important cancers (15%-30%) are MRI-invisible; (5) Targeted biopsies provide >80% concordance with whole-organ pathology. Early enthusiasm notwithstanding, cost-effectiveness is yet to be resolved, and the technologies remain in evolution. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. TARGETED PROSTATE BIOPSY: LESSONS LEARNED MIDST THE EVOLUTION OF A DISRUPTIVE TECHNOLOGY

    Science.gov (United States)

    Nassiri, Nima; Natarajan, Shyam; Margolis, Daniel J.; Marks, Leonard S.

    2015-01-01

    Lessons learned during a 6-year experience with more than 1200 patients undergoing targeted prostate biopsy via MRI/US fusion are reported: (1) The procedure is safe and efficient, requiring some 15–20 minutes in an office setting; (2) MRI is best performed by a radiologist with specialized training, employing a trans-abdominal multi-parametric approach and preferably a 3T magnet; (3) Grade of MRI suspicion is the most powerful predictor of biopsy results, e.g., Grade 5 usually represents cancer; (4) Some potentially-important cancers (15%–30%) are MRI-invisible; (5) Targeted biopsies provide >80% concordance with whole-organ pathology. Early enthusiasm notwithstanding, cost-effectiveness is yet to be resolved, and the technologies remain in evolution. PMID:26166671

  9. Microstructure evolution and surface cleaning of Cu nanoparticles during micro-forming fields activated sintering technology

    Directory of Open Access Journals (Sweden)

    Wu Mingxia

    2015-01-01

    Full Text Available For the purpose of extensive utilization of powder metallurgy to micro/nano- fabrication of materials, the micro gear was prepared by a novel method, named as micro- forming fields activated sintering technology (Micro-FAST. Surface-cleaning of particles, especially during the initial stage of sintering, is a crucial issue for the densification mechanism. However, up to date, the mechanism of surface-cleaning is too complicated to be known. In this paper, the process of surface-cleaning of Micro-FAST was studied, employing the high resolution transmission electron microscopy (HRTEM for observation of microstructure of micro-particles. According to the evolution of the microstructure, surface-cleaning is mainly ascribed to the effect of electro-thermal focusing. The process of surface-cleaning is achieved through rearrangement of grains, formation of vacancy, migration of vacancy and enhancement of electro-thermal focusing.

  10. Evolutions of Advanced Stamping CAE — Technology Adventures and Business Impact on Automotive Dies and Stamping

    Science.gov (United States)

    Wang, Chuantao (C. T.)

    2005-08-01

    In the past decade, sheet metal forming and die development has been transformed to a science-based and technology-driven engineering and manufacturing enterprise from a tryout-based craft. Stamping CAE, especially the sheet metal forming simulation, as one of the core components in digital die making and digital stamping, has played a key role in this historical transition. The stamping simulation technology and its industrial applications have greatly impacted automotive sheet metal product design, die developments, die construction and tryout, and production stamping. The stamping CAE community has successfully resolved the traditional formability problems such as splits and wrinkles. The evolution of the stamping CAE technology and business demands opens even greater opportunities and challenges to stamping CAE community in the areas of (1) continuously improving simulation accuracy, drastically reducing simulation time-in-system, and improving operationalability (friendliness), (2) resolving those historically difficult-to-resolve problems such as dimensional quality problems (springback and twist) and surface quality problems (distortion and skid/impact lines), (3) resolving total manufacturability problems in line die operations including blanking, draw/redraw, trim/piercing, and flanging, and (4) overcoming new problems in forming new sheet materials with new forming techniques. In this article, the author first provides an overview of the stamping CAE technology adventures and achievements, and industrial applications in the past decade. Then the author presents a summary of increasing manufacturability needs from the formability to total quality and total manufacturability of sheet metal stampings. Finally, the paper outlines the new needs and trends for continuous improvements and innovations to meet increasing challenges in line die formability and quality requirements in automotive stamping.

  11. On the Influential Factors of Industrial Technology Learning:an Empirical Study from LED Industry in Guangdong Province%广东LED产业技术学习影响因素实证研究

    Institute of Scientific and Technical Information of China (English)

    王月琴

    2013-01-01

    以215家广东LED企业为样本,采用结构方程模型检验知识的缄默性、复杂性对产业技术学习绩效的影响,以及网络属性对知识的缄默性、复杂性与产业技术学习绩效关系的调节效应.研究结果显示,(1)知识的缄默性、复杂性对广东LED产业技术学习绩效具有显著的负向影响;(2)尽管广东LED企业充分利用了网络中心性的有利位置去获取缄默性较高的外部技术知识,但是对于复杂程度较高的外部技术知识,网络中心性没有起到明显的调节作用;(3)广东LED企业与外部创新资源的强关系有利于其尽快掌握外部LED产业技术中的缄默性知识以及复杂程度较高的核心产业技术.%Appling structural equation model, this paper conducts an empirical study on the influential factors of LED industrial technology learning in Guangdong province. Evidences indicate that; (1) the tacitness and complexity of knowledge have negative effects on technology learning performance in Guangdong LED industry; (2) although Guangdong LED enterprises make full use of the centrality of their position in the LED industrial network to acquire external knowledge with high tacitness, the network centrality has no obvious adjustment effect as to external knowledge with high complexity; (3) stong ties with external innovation resources are helpful for Guangdong LED industry to get external tacit knowledge and core industrial technology with high complexity.

  12. Spectroradiometry for LED characterization

    DEFF Research Database (Denmark)

    Dam-Hansen, Carsten

    Radiospectroscopy is the absolute measurement of electromagnetic radiation within a specific wavelength range. For characterization of LED components, light sources and lamps we are interested in absolute measurement of the spectral power distribution, SPD, in the visible and near infrared region....... Using integrating spheres for light collection setups for absolute total spectral flux is realized at the LED Light Lab at DTU Fotonik, Risø Campus. From these, both total radiant and luminous flux is determined and through electrical power measurement also the efficiency is determined. From the SPD...... colorimetric quantities like color coordinates, color temperature and color rendering indices are calculated. The facilities and special issues concerning LED measurements compared to traditional light sources are explained and examples from the “LED lighting quality program”, a project supported by the Danish...

  13. Modeling LED street lighting.

    Science.gov (United States)

    Moreno, Ivan; Avendaño-Alejo, Maximino; Saucedo-A, Tonatiuh; Bugarin, Alejandra

    2014-07-10

    LED luminaires may deliver precise illumination patterns to control light pollution, comfort, visibility, and light utilization efficiency. Here, we provide simple equations to determine how the light distributes in the streets. In particular, we model the illuminance spatial distribution as a function of Cartesian coordinates on a floor, road, or street. The equations show explicit dependence on the luminary position (pole height and arm length), luminary angle (fixture tilt), and the angular intensity profile (radiation pattern) of the LED luminary. To achieve this, we propose two mathematical representations to model the sophisticated intensity profiles of LED luminaries. Furthermore, we model the light utilization efficiency, illumination uniformity, and veiling luminance of glare due to one or several LED streetlamps.

  14. LEDs Are Diodes.

    Science.gov (United States)

    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)

  15. RS-232 Led Board

    CERN Document Server

    Tskhvaradze, Vladimir

    2007-01-01

    This article demonstrates how to develop a Microchip PIC16F84 based device that supports RS-232 interface with PC. Circuit (LED Board) design and software development will be discussed. PicBasic Pro Compiler from microEngineering Labs, Inc. is used for PIC programming. Development of LED Board Control Console using C/C++ is also briefly discussed. The project requires basic work experience with Microchip PICs, serial communication and programming.

  16. High-efficiency Technology of LED White Light Based on Phosphor Glass%基于荧光玻璃的高效LED白光技术

    Institute of Scientific and Technical Information of China (English)

    黄波; 童玉珍; 李成明; 胡西多; 何苗; 郑树文; 李述体

    2016-01-01

    采用高温熔融法制备了一定质量比例的SiO2-YAG∶Ce3+片状荧光玻璃,厚度为0.2 mm,分析其XRD物相、光学和SEM微观结构、PL光谱。结果表明:荧光玻璃保留了晶相,荧光粉颗粒在玻璃基质中均匀分布,荧光玻璃和荧光粉的激发响应关系一致。在465 nm蓝光激发下,发射波长均在535 nm附近,表明荧光玻璃除含有玻璃相,还有荧光粉的物质结构特性。将不同波长蓝光芯片与不同荧光粉含量的荧光玻璃进行封装测试,结果表明:器件的流明效率可达到234.81 lm/W;色温和显色指数均随荧光粉含量增加而单调下降,呈现高色温和低显色指数;荧光粉质量分数从6%增加至15%时,不同波长激发下的色坐标x与y呈现大致相同的线性变化率。采用450 nm激光激发荧光玻璃,测试样品温度变化发现温升较缓,温降迅速,耐热性能优越。实验结果表明,将荧光玻璃用于LED白光照明封装,能实现流明效率和耐热性能的大幅提升,形成良好的白光输出。%SiO2 glass powder and a certain mass proportion of YAG∶ Ce3 +phosphor powder were taken to prepare SiO2-YAG∶Ce3+ PG with melting method, and then the samples were prepared into 0. 2 mm thickness for XRD phase, structure of optical micrographs and SEM, and PL spectrum test analysis. The results show that the phase of phosphor is retained in PG and the phosphor particles are uniformly distributed in the glass matrix. Consistent excitation and response relationship of PG and phosphor is observed that the excitation wavelength is about 465 nm and the emission wavelength is about 535 nm. The structure characteristics of phosphor are retained in PG except the glass phase. The blue LED chips with different wavelengths were packaged with the PG samples. The test results indicate that the luminous efficiency can reach at 234. 81 lm/W, and the color temperature and CRI monotonically decrease with the increasing of phosphor content

  17. Genome-environment interactions and prospective technology assessment: evolution from pharmacogenomics to nutrigenomics and ecogenomics.

    Science.gov (United States)

    Ozdemir, Vural; Motulsky, Arno G; Kolker, Eugene; Godard, Béatrice

    2009-02-01

    The relationships between food, nutrition science, and health outcomes have been mapped over the past century. Genomic variation among individuals and populations is a new factor that enriches and challenges our understanding of these complex relationships. Hence, the confluence of nutritional science and genomics-nutrigenomics--was the focus of the OMICS: A Journal of Integrative Biology in December 2008 (Part 1). The 2009 Special Issue (Part 2) concludes the analysis of nutrigenomics research and innovations. Together, these two issues expand the scope and depth of critical scholarship in nutrigenomics, in keeping with an integrated multidisciplinary analysis across the bioscience, omics technology, social, ethical, intellectual property and policy dimensions. Historically, the field of pharmacogenetics provided the first examples of specifically identifiable gene variants predisposing to unexpected responses to drugs since the 1950s. Brewer coined the term ecogenetics in 1971 to broaden the concept of gene-environment interactions from drugs and nutrition to include environmental agents in general. In the mid-1990s, introduction of high-throughput technologies led to the terms pharmacogenomics, nutrigenomics and ecogenomics to describe, respectively, the contribution of genomic variability to differential responses to drugs, food, and environment defined in the broadest sense. The distinctions, if any, between these newer fields (e.g., nutrigenomics) and their predecessors (e.g., nutrigenetics) remain to be delineated. For nutrigenomics, its reliance on genome-wide analyses may lead to detection of new biological mechanisms governing host response to food. Recognizing "genome-environment interactions" as the conceptual thread that connects and runs through pharmacogenomics, nutrigenomics, and ecogenomics may contribute toward anticipatory governance and prospective real-time analysis of these omics fields. Such real-time analysis of omics technologies and

  18. Flashing LEDs for Microalgal Production.

    Science.gov (United States)

    Schulze, Peter S C; Guerra, Rui; Pereira, Hugo; Schüler, Lisa M; Varela, João C S

    2017-08-30

    Flashing lights are next-generation tools to mitigate light attenuation and increase the photosynthetic efficiency of microalgal cultivation systems illuminated by light-emitting diodes (LEDs). Optimal flashing light conditions depend on the reaction kinetics and properties of the linear electron transfer chain, energy dissipation, and storage mechanisms of a phototroph. In particular, extremely short and intense light flashes potentially mitigate light attenuation in photobioreactors without impairing photosynthesis. Intelligently controlling flashing light units and selecting electronic components can maximize light emission and energy efficiency. We discuss the biological, physical, and technical properties of flashing lights for algal production. We combine recent findings about photosynthetic pathways, self-shading in photobioreactors, and developments in solid-state technology towards the biotechnological application of LEDs to microalgal production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Evolution of Instrumentation for Detection of the Raman Effect as Driven by Available Technologies and by Developing Applications

    Science.gov (United States)

    Adar, Fran; Delhaye, Michel; DaSilva, Edouard

    2007-01-01

    The evolution of Raman instrumentation from the time of the initial report of the phenomenon in 1928 to 2006 is discussed. The first instruments were prism-based spectrographs using lenses for collimation and focusing and the 21st century instruments are also spectrographs, but they use CCD cameras. The Lippmann filter technology that appears to…

  20. Semiconducting polymer LEDs

    Directory of Open Access Journals (Sweden)

    David Braun

    2002-06-01

    The field of semiconducting polymers has its root in the 1977 discovery of the semiconducting properties of polyacetylene1. This breakthrough earned Alan Heeger, Alan MacDiarmid, and Hideki Shirakawa the 2000 Nobel Prize in Chemistry for ‘the discovery and development of conductive polymers’2–5. Other review articles capture how more than two decades of developments in the physical and chemical understanding of these novel materials has led to new device applications as active and passive electronic and optoelectronic devices ranging from diodes and transistors to polymer LEDs, photodiodes, lasers, and solar cells6–11. Much interest in plastic devices derives from the opportunities to use clever control of polymer structure combined with relatively economical polymer synthesis and processing techniques to obtain simultaneous control over electronic, optical, chemical, and mechanical features5. This article focuses on the advances leading to polymer LEDs12–14.

  1. [LED lights in dermatology].

    Science.gov (United States)

    Noé, C; Pelletier-Aouizerate, M; Cartier, H

    2017-01-16

    The use in dermatology of light-emitting diodes (LEDs) continues to be surrounded by controversy. This is due mainly to poor knowledge of the physicochemical phases of a wide range of devices that are difficult to compare to one another, and also to divergences between irrefutable published evidence either at the level of in vitro studies or at the cellular level, and discordant clinical results in a variety of different indications: rejuvenation, acne, wound healing, leg ulcers, and cutaneous inflammatory or autoimmune processes. Therapeutic LEDs can emit wavelengths ranging from the ultraviolet, through visible light, to the near infrared (247-1300 nm), but only certain bands have so far demonstrated any real value. We feel certain that if this article remains factual, then readers will have a different, or at least more nuanced, opinion concerning the use of such LED devices in dermatology.

  2. The evolution of advanced mechanical defenses and potential technological applications of diatom shells.

    Science.gov (United States)

    Hamm, Christian E

    2005-01-01

    Diatoms are unicellular algae with silicified cell walls, which exhibit a high degree of symmetry and complexity. Their diversity is extraordinarily high; estimates suggest that about 10(5) marine and limnic species may exist. Recently, it was shown that diatom frustules are mechanically resilient, statically sophisticated structures made of a tough glass-like composite. Consequently, to break the frustules, predators have to generate large forces and invest large amounts of energy. In addition, they need feeding tools (e.g., mandibles or gastric mills) which are hard, tough, and resilient enough to resist high stress and wear, which are bound to occur when they feed on biomineralized objects such as diatoms or other biomineralized protists. Indeed, many copepods feeding on diatoms possess, in analogy to the enamelcoated teeth of mammals, amazingly complex, silica-laced mandibles. The highly developed adaptations both to protect and to break diatoms indicate that selection pressure is high to optimize material properties and the geometry of the shells to achieve mechanical strength of the overall structure. This paper discusses the mechanical challenges which force the development of mechanical defenses, and the structural components of the diatom frustules which indicate that evolutionary optimization has led to mechanically sophisticated structures. Understanding the diatom frustule from the nanometer scale up to the whole shell will provide new insights to advanced combinations of nanostructured composite ceramic materials and lightweight architecture for technological applications.

  3. Design methodologies for reliability of SSL LED boards

    NARCIS (Netherlands)

    Jakovenko, J.; Formánek, J.; Perpiñà, X.; Jorda, X.; Vellvehi, M.; Werkhoven, R.J.; Husák, M.; Kunen, J.M.G.; Bancken, P.; Bolt, P.J.; Gasse, A.

    2013-01-01

    This work presents a comparison of various LED board technologies from thermal, mechanical and reliability point of view provided by an accurate 3-D modelling. LED boards are proposed as a possible technology replacement of FR4 LED boards used in 400 lumen retrofit SSL lamps. Presented design method

  4. LED system reliability

    NARCIS (Netherlands)

    Driel, W.D. van; Yuan, C.A.; Koh, S.; Zhang, G.Q.

    2011-01-01

    This paper presents our effort to predict the system reliability of Solid State Lighting (SSL) applications. A SSL system is composed of a LED engine with micro-electronic driver(s) that supplies power to the optic design. Knowledge of system level reliability is not only a challenging scientific ex

  5. Spectroradiometry for LED characterization

    DEFF Research Database (Denmark)

    Dam-Hansen, Carsten

    Radiospectroscopy is the absolute measurement of electromagnetic radiation within a specific wavelength range. For characterization of LED components, light sources and lamps we are interested in absolute measurement of the spectral power distribution, SPD, in the visible and near infrared region...

  6. High Power UV LED Industrial Curing Systems

    Energy Technology Data Exchange (ETDEWEB)

    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.

  7. The influence of technological evolution over the museum’s architectural image

    Directory of Open Access Journals (Sweden)

    Magdalena Stănculescu

    2014-03-01

    Full Text Available The appropriation of technological progress is currently one of the touchstones of the architects; the speed of change is obvious around the world. Everything is regarded in a restructured outlook, constantly returning terms as: variability, freedom of expression, simplicity and essentiality of space and equipment, capacity to adapt over time. In theory must be marked the fact that it is evolving towards innovation, which is a constant interrogation of the past and a relentless attempt to anticipate the future. The evolution of the museum architectural expression includes extremely wide range of approaches, from simple construction, from demountable, modest materials up to large buildings, carried out on significant surface, which can bring to the forefront great variety of complex, current forms. It can be noticed the transition of just over one century, from the phase of architectural constraints, imposed by both formal and constructive, to a stage of boundless freedom, materialized to a variety of options. This paper brings together some selected examples of contemporary museums, performed by renowned architects, with comments that emphasize the architectural trends arising from these projects, capturing the plurality of directions and approaches.

  8. Thermal management for LED applications

    CERN Document Server

    Poppe, András

    2014-01-01

    Thermal Management for LED Applications provides state-of-the-art information on recent developments in thermal management as it relates to LEDs and LED-based systems and their applications. Coverage begins with an overview of the basics of thermal management including thermal design for LEDs, thermal characterization and testing of LEDs, and issues related to failure mechanisms and reliability and performance in harsh environments. Advances and recent developments in thermal management round out the book with discussions on advances in TIMs (thermal interface materials) for LED applications, advances in forced convection cooling of LEDs, and advances in heat sinks for LED assemblies. This book also: Presents a comprehensive overview of the basics of thermal management as it relates to LEDs and LED-based systems Discusses both design and thermal management considerations when manufacturing LEDs and LED-based systems Covers reliability and performance of LEDs in harsh environments Has a hands-on applications a...

  9. Design of Knight LED system

    Science.gov (United States)

    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.

  10. Monolithic Integration of GaN-based LEDs

    Energy Technology Data Exchange (ETDEWEB)

    Ao, Jin-Ping, E-mail: jpao@ee.tokushima-u.ac.jp [Institute of Technology and Science, University of Tokushima 2-1 Minami-Josanjima, Tokushima 770-8506 (Japan)

    2011-02-01

    The technology of monolithically integrated GaN-based light-emitting diodes (LEDs) is reported. First, the technology details to realize monolithic integration are described, including the circuit design for high-voltage and alternating current (AC) operation and the technologies for device isolation. The performances of the fabricated monolithic LED arrays are then demonstrated. A monolithic series array with totally 40 LEDs exhibited expected operation function under AC bias. The operation voltage of the array is 72 V when 20 LEDs were connected in series. Some modified circuit designs for high-voltage operation and other monolithic LED arrays are finally reviewed.

  11. High-power LED package requirements

    Science.gov (United States)

    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.

  12. Advances in LEDs for automotive applications

    Science.gov (United States)

    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

  13. High-power UV-LED degradation: Continuous and cycled working condition influence

    Science.gov (United States)

    Arques-Orobon, F. J.; Nuñez, N.; Vazquez, M.; Segura-Antunez, C.; González-Posadas, V.

    2015-09-01

    High-power (HP) UV-LEDs can replace UV lamps for real-time fluoro-sensing applications by allowing portable and autonomous systems. However, HP UV-LEDs are not a mature technology, and there are still open issues regarding their performance evolution over time. This paper presents a reliability study of 3 W UV-LEDs, with special focus on LED degradation for two working conditions: continuous and cycled (30 s ON and 30 s OFF). Accelerated life tests are developed to evaluate the influence of temperature and electrical working conditions in high-power LEDs degradation, being the predominant failure mechanism the degradation of the package. An analysis that includes dynamic thermal and optical HP UV-LED measurements has been performed. Static thermal and stress simulation analysis with the finite element method (FEM) identifies the causes of package degradation. Accelerated life test results prove that HP UV-LEDs working in cycled condition have a better performance than those working in continuous condition.

  14. Standards for Tunnel and Road LED Lighting Application Technologies%上海市隧道、道路LED照明应用技术标准研究综述

    Institute of Scientific and Technical Information of China (English)

    杨方勤

    2014-01-01

    The paper summarizes the research on the development of standards for tunnels and roads LED lighting application in Shanghai, analyzes the existing problems on LED road lamps and lighting design, introduces the experiments and testing results, and summarizes current problems of LED street lighting, proposing that LED lighting energy conservation should be “systematic energy saving” throughout the full life cycle based on the integration of products and applications.

  15. Petroleum technologies: recent and future evolutions. Consequences on the gas production line; Technologies petrolieres: evolutions recentes et futures. Consequences sur la chaine gaz

    Energy Technology Data Exchange (ETDEWEB)

    Freud, E. [Institut Francais du Petrole, 92 - Rueil-Malmaison (France)

    1998-03-01

    This paper describes how recent technological progresses should solve the difficulties encountered in the exploitation of natural gas fields in hard environments (far away or isolated fields, deep offshore, small or complex fields, production requiring a complex processing). These techniques concern: the exploration of fields and reservoirs, the deep-sea drilling and production (poly-phase pumping, hydrates formation control), the processing of crudes (water/oil and oil/gas separation, dehydration, de-acidification, removal of impurities), the transport (gas-pipelines, LNG and chemical conversion). (J.S.)

  16. Ln(III) complexes as potential phosphors for white LEDs

    NARCIS (Netherlands)

    Akerboom, Sebastiaan

    2013-01-01

    Generating white light with LED technology requires a trick; one of them is to use color-converting (phosphor) layer that covers the LED chip. Suitable phosphors that can be excited with LEDs are scarce, necessitating research in this area. Complexes of the trivalent lanthanoids are interesting cand

  17. Quantitative analysis of macroevolutionary patterning in technological evolution: Bicycle design from 1800 to 2000

    OpenAIRE

    Lake, M. W.; Venti, J.

    2009-01-01

    Book description: This volume offers an integrative approach to the application of evolutionary theory in studies of cultural transmission and social evolution and reveals the enormous range of ways in which Darwinian ideas can lead to productive empirical research, the touchstone of any worthwhile theoretical perspective. While many recent works on cultural evolution adopt a specific theoretical framework, such as dual inheritance theory or human behavioral ecology, Pattern and Process in Cu...

  18. 三网技术演进与融合趋势%Technology Evolution and Convergence Trend of Network

    Institute of Scientific and Technical Information of China (English)

    王瑞刚

    2011-01-01

    After analyzing the technology evolution for telecommunication network, Internet, broadcast and television network, it is offered that network convergence is network technology development trend. Discussing the essence, motivity and development status of network convergence point out that convergence and evolution accelerates one another, and network convergence is a long process getting across layer convergence toward to evolution for next generation network.%对电信网、互联网和广播电视网的技术演进进行了分析,认为三网融合是技术发展的必然趋势.对三网融合的本质、原动力以及在我国的发展现状进行探讨,指出三网融合与技术演进存在相互促进作用,三网融合是三网在向下一代网络演进中通过分层逐步融合的长期过程.

  19. 100 LPW 800 Lm Warm White LED

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Decai [Philips Lumileds Lighting Company, San Jose, CA (United States)

    2010-10-31

    efficiency (PPE) through improvement in phosphor-package interactions. Another achievement in the development of the phosphor integration technology is the demonstration of tight color control. The high power WW LED product developed has been proven to have good reliability. The manufacturing of the product will be done in Philips Lumileds LUXEON Rebel production line which has produced billions of high power LEDs. The first high power WW LED product will be released to the market in 2011.

  20. White LED with High Package Extraction Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    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

  1. Thermo-mechanical model optimization of HB-LED packaging

    NARCIS (Netherlands)

    Yuan, C.A.; Erinc, M.; Gielen, A.W.J.; Waal, A. van der; Driel, W. van; Zhang, K.

    2011-01-01

    Lighting is an advancing phenomenon both on the technology and on the market level due to the rapid development of the solid state lighting technology. The efforts in improving the efficacy of high brightness LED's (HB-LED) have concentrated on the packaging architecture. Packaging plays a significa

  2. A Lifetime Prediction Method for LEDs Considering Real Mission Profiles

    OpenAIRE

    Qu, Xiaohui; Wang, Huai; Zhan, Xiaoqing; Blaabjerg, Frede; Chung, Henry Shu-Hung

    2017-01-01

    The Light-Emitting Diode (LED) has become a very promising alternative lighting source with the advantages of longer lifetime and higher efficiency than traditional ones. The lifetime prediction of LEDs is important to guide the LED system designers to fulfill the design specifications and to benchmark the cost-competitiveness of different lighting technologies. However, the existing lifetime data released by LED manufacturers or standard organizations are usually applicable only for some spe...

  3. Roughnecks, rock bits and rigs : the evolution of oil well drilling technology in Alberta, 1883-1970

    Energy Technology Data Exchange (ETDEWEB)

    Gow, A.

    2005-07-01

    This book provides a comprehensive review of the evolving technologies related to oil and gas exploration in the province of Alberta. Oil well drilling technology evolved significantly during the era of conventional oil exploration in the province, from 1883 through 1970. Technologies such as drill bits and power sources were developed largely through trial and error to meet the specific needs of individuals working in the oilfield. The competence and resolve to innovate by drill crews was told through accounts of evolution in drilling processes and equipment, along with personal accounts of those who worked on the rigs. The technology of the oilfield was placed into context with a summary of the history and geology of oil and gas in Alberta. The book also presents a considerate view of events in relation to those who invested in the industry, carried out research drilling and serviced the exploration industry. The first part of the book provides the background to the oil and gas industry. Part 2 examines the earliest technology, the standard cable tool drilling rig, the combination rig and some associated developments in drilling. The third part focuses on the rotary drilling rig and the final part outlines the types of challenges faced by the drillers and the hazards of working on Alberta's rigs. refs., tabs., figs.

  4. Evolution of Wireless New Technologies%对无线新技术演进的思考

    Institute of Scientific and Technical Information of China (English)

    向际鹰

    2015-01-01

    介绍了中兴通讯对未来无线新技术走向的整体看法。认为现有的5G侯选技术仍然是在传统空间、时间、频率3种自由度的基础上做增强。而在这些增强中,需要尤其关注一些无须改变4G空口就可以直接使用的5G技术,例如大规模多输入多输出(MIMO)、超密网(UDN)等。还认为所有无线新技术都将持续演进。随着5G标准的制订,用户体验将得到本质的提升。%An overview of wireless new technologies over next few years is given. The candidate technologies for 5G are being enhanced in terms of time, frequency, and space diversity. We should focus on 5G technologies that can be used directly and do not require the 4G port to be changed. Such technologies include massive multi-imput multi-output (MIMO) and ultra dense network (UDN). As the evolution of the technology, the user experience wil be greatly improved in term of throughput and latency.

  5. A simple interpretation of the growth of scientific/technological research impact leading to hype-type evolution curves

    CERN Document Server

    Campani, Marco

    2014-01-01

    The empirical and theoretical justification of Gartner hype curves is a very relevant open question in the field of Technological Life Cycle analysis. The scope of the present paper is to introduce a simple model describing the growth of scientific/technological research impact, in the specific case where science is the main source of a new idea driving a technological development, leading to hype-type evolution curves. The main idea of the model is that, in a first stage, the growth of the scientific interest of a new specific field (as can be measured by publication numbers) basically follows the classical logistic growth curve. At a second stage, starting at a later trigger time, the technological development based on that scientific idea (as can be measured by patent deposits) can be described as the integral (in a mathematical sense) of the first curve, since technology is based on the overall accumulated scientific knowledge. The model is tested through a bibliometric analysis of the publication and pat...

  6. Affordable underwater wireless optical communication using LEDs

    Science.gov (United States)

    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

  7. Endogenous Innovation in Chinese IC Firms: A Case Study Based on the Technology Strategy Evolution of NSBIC

    Institute of Scientific and Technical Information of China (English)

    WANG Min; YIN Lu

    2006-01-01

    It is a common sense that enterprise is the principal of endogenous innovation, but why many firms do not innovate actively? What kind of difficulty will enterprises suffer in endogenous innovation? What can the government do for the endogenous innovation? These questions are very crucial to realize endogenous innovation. This paper tries to answer the questions mentioned above from the perspective of technology evolution. The industrial environment of emerging technology is emphasized for analyzing the endogenous innovation in Chinese enterprises. The process of endogenous innovation in NanShanBridge Co. Ltd (NSBIC),which is an IC design firm, is analyzed as a case. From the case study, we can answer the questions above in certain extent, give some suggestions to the enterprises as a later-comer, and present some advice to government.

  8. Business Models for Sustainable Technologies: Exploring Business Model Evolution in the Case of Electric Vehicles

    NARCIS (Netherlands)

    Bohnsack, R.; Pinkse, J.; Kolk, A.

    2014-01-01

    Sustainable technologies challenge prevailing business practices, especially in industries that depend heavily on the use of fossil fuels. Firms are therefore in need of business models that transform the specific characteristics of sustainable technologies into new ways to create economic value and

  9. Keeping up with Our Students: The Evolution of Technology and Standards in Art Education

    Science.gov (United States)

    Patton, Ryan M.; Buffington, Melanie L.

    2016-01-01

    This article addresses the standards of technology in the visual arts, arguing the standards function as de facto policy, the guidelines that shape what teachers teach. In this study, we investigate how art education standards approach technology as a teaching tool and artmaking medium, analyzing the current National Visual Arts Standards, the…

  10. User Acceptance of Long-Term Evolution (LTE) Services: An Application of Extended Technology Acceptance Model

    Science.gov (United States)

    Park, Eunil; Kim, Ki Joon

    2013-01-01

    Purpose: The aim of this paper is to propose an integrated path model in order to explore user acceptance of long-term evolution (LTE) services by examining potential causal relationships between key psychological factors and user intention to use the services. Design/methodology/approach: Online survey data collected from 1,344 users are analysed…

  11. Bringing Evolution to a Technological Generation: A Case Study with the Video Game SPORE

    Science.gov (United States)

    Poli, DorothyBelle; Berenotto, Christopher; Blankenship, Sara; Piatkowski, Bryan; Bader, Geoffrey A.; Poore, Mark

    2012-01-01

    The video game SPORE was found to hold characteristics that stimulate higher-order thinking even though it rated poorly for accurate science. Interested in evaluating whether a scientifically inaccurate video game could be used effectively, we exposed students to SPORE during an evolution course. Students that played the game reported that they…

  12. Geochemical Mapping——Evolution of Its Aims, Ideas and Technology

    Institute of Scientific and Technical Information of China (English)

    XIE Xuejing

    2008-01-01

    The development of geochemical mapping progressed from local geochemical prospecting through regional geochemical exploration and regional geochemical mapping to national and global geochemical mapping. This paper discusses the evolution of aims, ideas and methodology of geochemical mapping in Western countries, Russia and China. The sophistication of geochemical mapping methodology will make great contributions to solving resources and environmental problems in the 21st century.

  13. Genre, technology and embodied interaction: The evolution of digital game genres and motion gaming

    Directory of Open Access Journals (Sweden)

    Andreas Gregersen

    2011-11-01

    Full Text Available Technology has been given relatively little attention in genre theory, but this article argues that material technologies can be important components in genre development. The argument is based on a historically informed analysis of digital games, with special attention paid to home console video games and recent genre developments within this domain commonly referred to as motion gaming. The main point is that digital game genres imply structured embodied activity. A constitutive element of digital game mediation is a control interface geared to player embodiment, and I propose the concept of ‘interaction modes’ to describe the coupling of technology and player embodiment and show how this can be integrated with genre theory. The resulting framework allows for increased attention to continuity and change in game and communication genres, material and digital technologies, and the related interaction modes.

  14. The future of pharmaceutical manufacturing in the context of the scientific, social, technological and economic evolution.

    Science.gov (United States)

    Stegemann, Sven

    2016-07-30

    Healthcare provision is one of the import elements of modern societies. Life sciences and technology has made substantial progress over the past century and is continuing to evolve exponentially in many different areas. The use of genotypic and phenotypic information in drug discovery and drug therapy, the increasing wealth around the world, growing patient involvement through information and communication technology and finally innovations in pharmaceutical manufacturing technology are transforming the provision of healthcare. The adoption of this new science and technology is going to happen due to the synergistic effects and visible benefits for the society and healthcare systems. The different aspects driving advanced pharmaceutical manufacturing are reviewed to identify future research direction to assure overall acceptance and adoption into healthcare practice. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Evolution of Monolithic Technology for Wireless Communications: GaN MMIC Power Amplifiers For Microwave Radios

    Directory of Open Access Journals (Sweden)

    Vittorio Camarchia

    2014-09-01

    Full Text Available This paper presents the progress of monolithic technology for microwaveapplication, focusing on gallium nitride technology advances in the realization of integratedpower amplifiers. Three design examples, developed for microwave backhaul radios, areshown. The first design is a 7 GHz Doherty developed with a research foundry, while thesecond and the third are a 7 GHz Doherty and a 7–15 GHz dual-band combined poweramplifiers, both based on a commercial foundry process. The employed architectures, themain design steps and the pros and cons of using gallium nitride technology are highlighted.The measured performance demonstrates the potentialities of the employed technology, andthe progress in the accuracy, reliability and performance of the process.

  16. A New Cultivation-Evolution Technology of Accident Immune Function for a Petrochemical Enterprise

    Institute of Scientific and Technical Information of China (English)

    Yang Zhenhong; Zhang Xuhua; Wang Xiangyao; Wang Zhihu; Liu Yan; Zhang Xuan

    2007-01-01

    For the purpose of developing an immune function on production accidents in a petrochemical enterprise, a new cultivation-evolution approach of preventive mechanism is suggested by analyzing various factors relating to immune deficiency syndrome and by referring to immunity genetic algorithm and relevant concepts applied in medicine science. Accident-immunity system for highly hazardous petrochemical enterprise, which is made up of its productive system's Safety Organ and Safety Organization, is typically an evolution-cultivation progress for immune function, The new B immune cell is generated after several layers' screening, clone expanding, receptor editing, organizing in immune system of work accident in petrochemical enterprise. There is a B immune cell with high appetency and a manipulative function chain for accident-immunity. Taking the antigen of accidents in industry as the target function and the immune antibody as the solution, the authors carried out a computation diagram for prediction of appetency between the antigen and antibody.

  17. Business models for sustainable technologies: Exploring business model evolution in the case of electric vehicles

    OpenAIRE

    Bohnsack, R.; Pinkse, J.; van der Kolk, A

    2014-01-01

    International audience; Sustainable technologies challenge prevailing business practices, especially in industries that depend heavily on the use of fossil fuels. Firms are therefore in need of business models that transform the specific characteristics of sustainable technologies into new ways to create economic value and overcome the barriers that stand in the way of their market penetration. A key issue is the respective impact of incumbent and entrepreneurial firms' path-dependent behavio...

  18. Mobile Technology in the Perioperative Arena: Rapid Evolution and Future Disruption.

    Science.gov (United States)

    Rothman, Brian S; Gupta, Rajnish K; McEvoy, Matthew D

    2017-03-01

    Throughout the history of medicine, physicians have relied upon disruptive innovations and technologies to improve the quality of care delivered, patient outcomes, and patient satisfaction. The implementation of mobile technology in health care is quickly becoming the next disruptive technology. We first review the history of mobile technology over the past 3 decades, discuss the impact of hardware and software, explore the rapid expansion of applications (apps), and evaluate the adoption of mobile technology in health care. Next, we discuss how technology serves as the vehicle that can transform traditional didactic learning into one that adapts to the learning behavior of the student by using concepts such as the flipped classroom, just-in-time learning, social media, and Web 2.0/3.0. The focus in this modern education paradigm is shifting from teacher-centric to learner-centric, including providers and patients, and is being delivered as context-sensitive, or semantic, learning. Finally, we present the methods by which connected health systems via mobile devices increase information collection and analysis from patients in both clinical care and research environments. This enhanced patient and provider connection has demonstrated benefits including reducing unnecessary hospital readmissions, improved perioperative health maintenance coordination, and improved care in remote and underserved areas. A significant portion of the future of health care, and specifically perioperative medicine, revolves around mobile technology, nimble learners, patient-specific information and decision-making, and continuous connectivity between patients and health care systems. As such, an understanding of developing or evaluating mobile technology likely will be important for anesthesiologists, particularly with an ever-expanding scope of practice in perioperative medicine.

  19. Fractal characterization for the mining crack evolution process of overlying strata based on microseismic monitoring technology

    Institute of Scientific and Technical Information of China (English)

    Liu Chao; Xue Junhua; Yu Guofeng; Cheng Xiaoyu

    2016-01-01

    In order to study the evolution laws during the development process of the coal face overburden rock mining-induced fissure, we studied the process of evolution of overburden rock mining-induced fissures and dynamically quantitatively described its fractal laws, based on the high-precision microseismic mon-itoring method and the nonlinear Fractal Geometry Theory. The results show that:the overburden rock mining-induced fissure fractal dimension experiences two periodic change processes with the coal face advance, namely a Small ? Big ? Small process, which tends to be stable; the functional relationship between the extraction step distance and the overburden rock mining-induced fissure fractal dimension is a cubic curve. The results suggest that the fractal dimension reflects the evolution characteristics of the overburden rock mining-induced fissure, which can be used as an evaluation index of the stability of the overburden rock strata, and it provides theoretical guidance for stability analysis of the overburden rock strata, goaf roof control and the support movements in the mining face.

  20. Has Human Evolution Stopped?

    OpenAIRE

    TEMPLETON, Alan R

    2010-01-01

    It has been argued that human evolution has stopped because humans now adapt to their environment via cultural evolution and not biological evolution. However, all organisms adapt to their environment, and humans are no exception. Culture defines much of the human environment, so cultural evolution has actually led to adaptive evolution in humans. Examples are given to illustrate the rapid pace of adaptive evolution in response to cultural innovations. These adaptive responses have important ...

  1. Using Multicore Technologies to Speed Up Complex Simulations of Population Evolution

    Directory of Open Access Journals (Sweden)

    Mauricio Guevara-Souza

    2013-01-01

    Full Text Available We explore with the use of multicore processing technologies for conducting simulations on population replacement of disease vectors. In our model, a native population of simulated vectors is inoculated with a small exogenous population of vectors that have been infected with the Wolbachia bacteria, which confers immunity to the disease. We conducted a series of computational simulations to study the conditions required by the invading population to take over the native population. Given the computational burden of this study, we decided to take advantage of modern multicore processor technologies for reducing the time required for the simulations. Overall, the results seem promising both in terms of the application and the use of multicore technologies.

  2. Percussive technology in human evolution: an introduction to a comparative approach in fossil and living primates.

    Science.gov (United States)

    de la Torre, Ignacio; Hirata, Satoshi

    2015-11-19

    Percussive technology is part of the behavioural suite of several fossil and living primates. Stone Age ancestors used lithic artefacts in pounding activities, which could have been most important in the earliest stages of stone working. This has relevant evolutionary implications, as other primates such as chimpanzees and some monkeys use stone hammer-and-anvil combinations to crack hard-shelled foodstuffs. Parallels between primate percussive technologies and early archaeological sites need to be further explored in order to assess the emergence of technological behaviour in our evolutionary line, and firmly establish bridges between Primatology and Archaeology. What are the anatomical, cognitive and ecological constraints of percussive technology? How common are percussive activities in the Stone Age and among living primates? What is their functional significance? How similar are archaeological percussive tools and those made by non-human primates? This issue of Phil. Trans. addresses some of these questions by presenting case studies with a wide chronological, geographical and disciplinary coverage. The studies presented here cover studies of Brazilian capuchins, captive chimpanzees and chimpanzees in the wild, research on the use of percussive technology among modern humans and recent hunter-gatherers in Australia, the Near East and Europe, and archaeological examples of this behaviour from a million years ago to the Holocene. In summary, the breadth and depth of research compiled here should make this issue of Philosophical Transactions of the Royal Society B, a landmark step forward towards a better understanding of percussive technology, a unique behaviour shared by some modern and fossil primates.

  3. 设施园艺半导体照明及其研发中的科技问题%Current Science & Technology Urgent Issues to Be Solved for Research and Development of LED Lighting in Protected Horticulture

    Institute of Scientific and Technical Information of China (English)

    刘文科; 杨其长

    2014-01-01

    为推进设施园艺照明研发及产业化发展,需解决的科学问题包括:(1)光质生物学。弄清单一光质及复合光质对植物和食用菌生长发育和产量品质影响的生理代谢、分子生物学及蛋白组学机理;生物种类及品种间光质适应性和利用差异性机理;光质与环境其它因子互作的生物学机制;设施生物光质数量属性有效阈值和基准值(如补偿点、饱和点与光胁迫阈值)等;(2)逆境光质生物学。明确单色及复合弱光、强光及连续光照下光合机构、代谢系统运转效率的响应机理及其农学意义等。需解决的技术问题包括:(1)建立设施园艺各生产领域特定生物生长发育、优质高产所需的光照配方;(2)制定农业生物光环境控制策略;(3)研发LED光源装置、灯具及计算机智能控制系统。%In order to accelerate the industrialization and scaled application development of LLPH , science issues in LLPH include two aspects .One issue is photobiology , to clarify the responsive mechanisms of physiology, molecular biology and proteomics of plant and edible fungi under monochromatic and compound light;Interspecific and intervarietal variations of light quality utilization for plants and edible fungi;interaction mechanisms between light quality and other environmental factors;available thresholds and critical values of light quality ( i.e.compensation point, saturation point, and stress thresholds ).The other issue is stress photobiology, to clarify the influences of weak lighting , strong lighting and continuous lighting of LED monochromatic or compound light on efficiencies of photosynthetic apparatus and metabolism systems .Three technology issues should be considered , including ( 1 ) optimal light recipes for high productivity; ( 2 ) establishment of light environmental control strategy for various production fields;(3) development of LED light source devices, lamps

  4. Somatic Embryogenesis in Coffee: The Evolution of Biotechnology and the Integration of Omics Technologies Offer Great Opportunities.

    Science.gov (United States)

    Campos, Nádia A; Panis, Bart; Carpentier, Sebastien C

    2017-01-01

    One of the most important crops cultivated around the world is coffee. There are two main cultivated species, Coffea arabica and C. canephora. Both species are difficult to improve through conventional breeding, taking at least 20 years to produce a new cultivar. Biotechnological tools such as genetic transformation, micropropagation and somatic embryogenesis (SE) have been extensively studied in order to provide practical results for coffee improvement. While genetic transformation got many attention in the past and is booming with the CRISPR technology, micropropagation and SE are still the major bottle neck and urgently need more attention. The methodologies to induce SE and the further development of the embryos are genotype-dependent, what leads to an almost empirical development of specific protocols for each cultivar or clone. This is a serious limitation and excludes a general comprehensive understanding of the process as a whole. The aim of this review is to provide an overview of which achievements and molecular insights have been gained in (coffee) somatic embryogenesis and encourage researchers to invest further in the in vitro technology and combine it with the latest omics techniques (genomics, transcriptomics, proteomics, metabolomics, and phenomics). We conclude that the evolution of biotechnology and the integration of omics technologies offer great opportunities to (i) optimize the production process of SE and the subsequent conversion into rooted plantlets and (ii) to screen for possible somaclonal variation. However, currently the usage of the latest biotechnology did not pass the stage beyond proof of potential and needs to further improve.

  5. 5th October 2011 - Vienna Science and Technology Fund Board of Directors ((WWTF) led by Its President, Lord Mayor and Governor of Vienna M. Häupl, signing the guest book with Head of International relations F. Pauss and Director for Administration and General Infrastructure S. Lettow.

    CERN Multimedia

    2011-01-01

    5th October 2011 - Vienna Science and Technology Fund Board of Directors ((WWTF) led by Its President, Lord Mayor and Governor of Vienna M. Häupl, signing the guest book with Head of International relations F. Pauss and Director for Administration and General Infrastructure S. Lettow.

  6. Use of micro-emulsion technology for the directed evolution of antibodies.

    Science.gov (United States)

    Buhr, Diane L; Acca, Felicity E; Holland, Erika G; Johnson, Katie; Maksymiuk, Gail M; Vaill, Ada; Kay, Brian K; Weitz, David A; Weiner, Michael P; Kiss, Margaret M

    2012-09-01

    Affinity reagents, such as antibodies, are needed to study protein expression patterns, sub-cellular localization, and post-translational modifications in complex mixtures and tissues. Phage Emulsion, Secretion, and Capture (ESCape) is a novel micro-emulsion technology that utilizes water-in-oil (W/O) emulsions for the identification and isolation of cells secreting phage particles that display desirable antibodies. Using this method, a large library of antibody-displaying phage will bind to beads in individual compartments. Rather than using biopanning on a large mixed population, phage micro-emulsion technology allows us to individually query clonal populations of amplified phage against the antigen. The use of emulsions to generate microdroplets has the promise of accelerating phage selection experiments by permitting fine discrimination of kinetic parameters for binding to targets. In this study, we demonstrate the ability of phage micro-emulsion technology to distinguish two scFvs with a 300-fold difference in binding affinities (100nM and 300pM, respectively). In addition, we describe the application of phage micro-emulsion technology for the selection of scFvs that are resistant to elevated temperatures. Copyright © 2012. Published by Elsevier Inc.

  7. Historical Evolution of Instructional Technology in Teacher Education Programs: A Ten-Year Update

    Science.gov (United States)

    Betrus, Anthony

    2012-01-01

    The content and emphasis of the introductory technology courses for undergraduate preservice teachers has historically been examined, with the earliest study conducted by Stracke in 1932. In an attempt to identify trends in the course DeKieffer conducted a series of studies over ten year intervals, in 1947, 1957, 1967, and 1977. In 2000 the first…

  8. Evolution and revolution: gauging the impact of technological and technical innovation on Olympic performance.

    Science.gov (United States)

    Balmer, Nigel; Pleasence, Pascoe; Nevill, Alan

    2012-01-01

    A number of studies have pointed to a plateauing of athletic performance, with the suggestion that further improvements will need to be driven by revolutions in technology or technique. In the present study, we examine post-war men's Olympic performance in jumping events (pole vault, long jump, high jump, triple jump) to determine whether performance has indeed plateaued and to present techniques, derived from models of human growth, for assessing the impact of technological and technical innovation over time (logistic and double logistic models of growth). Significantly, two of the events involve well-documented changes in technology (pole material in pole vault) or technique (the Fosbury Flop in high jump), while the other two do not. We find that in all four cases, performance appears to have plateaued and that no further "general" improvement should be expected. In the case of high jump, the double logistic model provides a convenient method for modelling and quantifying a performance intervention (in this case the Fosbury Flop). However, some shortcomings are revealed for pole vault, where evolutionary post-war improvements and innovation (fibre glass poles) were concurrent, preventing their separate identification in the model. In all four events, it is argued that further general growth in performance will indeed need to rely predominantly on technological or technical innovation.

  9. New Phosphors for White LEDs

    Institute of Scientific and Technical Information of China (English)

    LIU Ru-Shi

    2004-01-01

    White light-emitting diodes (WLEDs) have matched the emission efficiency of florescent lights and will rapidly spread as light source for homes and offices in the next 5 to 10 years. WLEDs provide a light element having a semiconductor light emitting layer (blue or UV LEDs) and photoluminescence phosphors. GaN-based highly efficient blue InGaN LEDs combined with phosphors can produce white light. These solid-state LED lamps have a number of advantages over conventional incandescent bulbs and halogen lamps, such as high efficiency to convert electrical energy into light, reliability, and long operating lifetime (about 100,000 hours). For the purpose of development of high energy-efficient white light sources, we need to produce highly efficient new phosphors, which can absorb excitation energy from blue or UV LEDs and generate emissions.In this paper, we investigate the development of blue or UV LEDs by the appropriate combination of new phosphors which can lead us to obtain high brightness white light. The criteria of choosing the best phosphors, for blue (380-450 nm) and UV (360-400 nm) LEDs, strongly depends on the absorption and emission of the phosphors. Moreover, the balance light between the light emission from blue LEDs and the yellow YAG:Ce,Gd phosphor is important to obtain white light with high color temperature. The phosphors with high efficiency which can be excited by UV LEDs are important to obtain the white light with high color rendering index.

  10. Experiencing LED: Lighting: New Form and Experiential Qualities Emerging in Lighting Systems using LED

    DEFF Research Database (Denmark)

    Petersen, Kjell Yngve; Kristensen, Ole; Søndergaard, Karin

    2012-01-01

    The project investigates what new forms and qualities of light emerge from technologies such as LED, with a particular focus on basic form qualities and parameters. Existing linear functional understandings of the relation between light source, light flow, reflection and visibility is challenged ...... by relational understandings, where the materiality and visibility of the light emerge through mutual influences between several adaptive and transformative elements....

  11. Technological advances of compressors in refrigerating machines. Evolutions technologiques des compresseurs de machines frigorifiques

    Energy Technology Data Exchange (ETDEWEB)

    Sartre, V.; Lallemand, M. (Centre National de la Recherche Scientifique, 69 - Villleurbanne (France)); Chiaffi, M. (Societe Bertin et Compagnie, 78 - Plaisir (France))

    1994-03-01

    The present study is related to the development of compressors for heat pumps and refrigerating machines. For a given application, various compressor technologies are possible. The choice is often dictated by the experience acquired on a compressor type, ensuring good reliability and a reasonable cost of the plant. In our study, we examine the limits of various compressor types: piston, screw, scroll, rotary vane, rolling piston and centrifugal. A comparison of the theoretical and practical limits of the compressors' operating ranges shows the necessity of better adaptation of the compressor type to each application. Finally, we suggest the main research focus for the development of future compressors. The new technologies should evolve towards a variable-speed operation, without lubricating oil or with refrigerant lubrication. Acoustic comfort is also an important criterion. (author)

  12. Ensuring Energy Efficient 5G User Equipment by Technology Evolution and Reuse

    DEFF Research Database (Denmark)

    Lauridsen, Mads; Berardinelli, Gilberto; Sørensen, Troels Bundgaard

    2014-01-01

    Research on fifth generation (5G) radio access technology (RAT) is ramping up, with the goal of significantly improving user data rates and latency compared to previous radio generations. While energy efficiency (EE) of the user equipment (UE) was not a key optimization parameter for the current...... standards, it is anticipated to become a distinguishing factor for 5G. In this paper, we analyze established and emerging technological solutions for features such as waveform, frame structure, duplexing and multiple antenna transmission from an EE perspective. Our contribution is to identify and discuss...... the features’ pros and cons in achieving high performance in terms of data rate and/or latency while limiting their effect on the UE power consumption. Based on the discussion we give general recommendations for an energy efficient 5G design in the context of a previously proposed RAT concept....

  13. INFLUENCE OF COLD ROLLING TECHNOLOGY ON TEXTURE EVOLUTION OF IF STEEL

    Institute of Scientific and Technical Information of China (English)

    J.X. Li; X.H. Liu; G.D. Wang

    2002-01-01

    Two kinds of cold rolling experiments, single cold rolling and double cold rolling, werecarried out on one titanium stabilized interstitial free (IF) steel that has been warmrolled at ferrite temperature. The main aim was to investigate the evolution of rollingand annealing textures from the well known behavior observed under single cold rollingcondition to the less understood double cold rolling by using orientation distributionfunction (ODF). In the twice cold rolled samples, the annealing texture comprises onlyfirst round of rolling. Accordingly both the once cold rolled sample and the twice coldrolled sample with heavy reduction in the first round of rolling have much complextexture components. They are related to the formation of initial {111} subgrain andthe priority growth of stable {111} nucleus.

  14. Design in nature how the constructal law governs evolution in biology, physics, technology, and social organization

    CERN Document Server

    Bejan, Adrian

    2013-01-01

    In this groundbreaking book, Adrian Bejan takes the recurring patterns in nature—trees, tributaries, air passages, neural networks, and lightning bolts—and reveals how a single principle of physics, the constructal law, accounts for the evolution of these and many other designs in our world. Everything—from biological life to inanimate systems—generates shape and structure and evolves in a sequence of ever-improving designs in order to facilitate flow. River basins, cardiovascular systems, and bolts of lightning are very efficient flow systems to move a current—of water, blood, or electricity. Likewise, the more complex architecture of animals evolve to cover greater distance per unit of useful energy, or increase their flow across the land. Such designs also appear in human organizations, like the hierarchical “flowcharts” or reporting structures in corporations and political bodies. All are governed by the same principle, known as the constructal law, and configure and reconfigure themselves...

  15. Technological, political and economic changes and their implications for the evolution of broadcasting services

    DEFF Research Database (Denmark)

    Tadayoni, Reza

    2000-01-01

    The subject of this Ph.D. thesis is changes in the market for broadcasting services as a result of technological, political, and economic drivers. Broadcasting services can be categorised as a part of the ICT-based information and knowledge intensive services that have gone through radical changes...... and demand sites, scarcity of transmission resources, and the historical aspects that make the development of the broadcasting service market different from other information and knowledge intensive services....

  16. Technology-driven industry evolution in the telecom sector: The comparative case of Ecuador

    OpenAIRE

    Valarezo Garcia, Jose

    2014-01-01

    The purpose of this Thesis is to analyze the current situation of the telecom industry in Ecuador and its tendencies as part of the Telecom, Media and Technology TMT industry. The analysis elaborates about the ongoing effects at the industry and business levels of the widespread of mainstream products and services in the TMT market in the case of Ecuador, benchmarking it with the global context. In this sense, the case study is developed by addressing the following question: How the widesprea...

  17. Social learning and technological evolution during the Clovis colonization of the New World.

    Science.gov (United States)

    Eren, Metin I; Buchanan, Briggs; O'Brien, Michael J

    2015-03-01

    A long-standing debate in Pleistocene archaeology concerns the sources of variation in the technology of colonizing hunter-gatherers. One prominent example of this debate is Clovis technology (13,350-12,500 calendar years before present), which represents the earliest widespread and currently recognizable remains of hunter-gatherers in North America. Clovis projectile points appear to have been made the same way regardless of region, but several studies have documented differences in shape that appear to be regional. Two processes have been proposed for shape variation: (1) stochastic mechanisms such as copy error (drift) and (2) Clovis groups adapting their hunting equipment to the characteristics of prey and local habitat. We used statistical analysis of Clovis-point flake-scar pattern and geometric morphometrics to examine whether drift alone could cause significant differences in the technology of Stone Age colonizing hunter-gatherers. Importantly, our analysis was intraregional to rule out a priori environmental adaptation. Our analysis confirmed that the production technique was the same across the sample, but we found significant shape differences in Clovis point populations made from distinct stone outcrops. Given that current archaeological evidence suggests stone outcrops were "hubs" of regional Clovis activity, our dichotomous, intraregional results quantitatively confirm that Clovis foragers engaged in two tiers of social learning. The lower, ancestral tier relates to point production and can be tied to conformist transmission of tool-making processes across the Clovis population. The upper, derived tier relates to point shape, which can be tied to drift that resulted from increased forager interaction at different stone-outcrop hubs and decreased forager interaction among groups using different outcrops. Given that Clovis artifacts represent the earliest widespread and currently recognizable remains of hunter-gatherers in North America, our results

  18. Evolution and acceptability of medical applications of RFID implants among early users of technology.

    Science.gov (United States)

    Smith, Alan D

    2007-01-01

    RFID as a wireless identification technology that may be combined with microchip implants have tremendous potential in today's market. Although these implants have their advantages and disadvantages, recent improvements how allowed for implants designed for humans. Focus was given to the use of RFID tags and its effects on technology and CRM through a case study on VeriChip, the only corporation to hold the rights and the patent to the implantable chip for humans, and an empirically based study on working professionals to measure perceptions by early adopters of such technology. Through hypotheses-testing procedures, it was found that although some resistance to accept microchip implants was found in several applications, especially among gender, it was totally expected that healthcare and medical record keeping activities would be universally treated in a positive light and the use of authorities (namely governmental agencies) would be equally treated in a negative light by both sexes. Future trends and recommendations are presented along with statistical results collected through personal interviews.

  19. Total ankle replacement--evolution of the technology and future applications.

    Science.gov (United States)

    Yu, John J; Sheskier, Steven

    2014-01-01

    Total ankle arthroplasty was developed to reduce pain and retain motion of the ankle joint in patients with osteoarthritis much like its total hip and knee counterparts. Orthopaedic surgeons are well equipped to evaluate and treat patients with end-stage hip or knee arthritis; however, the management of patients with ankle arthritis represents a challenge to both general orthopaedic surgeons and to the foot and ankle surgeons to whom these patients are often referred. Although techniques for both hip and knee arthroplasty have evolved to provide long-term pain relief and functional improvement, neither ankle arthrodesis nor arthroplasty has demonstrated comparably favorable outcomes in long-term follow-up studies. Early ankle arthroplasty designs with highly constrained cemented components were abandoned due to unacceptably high failure rates and complications. While arthrodesis is still considered the "gold standard" for treatment of end-stage ankle arthritis, progression of adjacent joint arthrosis and diminished gait efficiency has led to a resurgence of interest in ankle arthroplasty. Long-term outcome studies for total ankle replacement found excellent or good results in 82% of patients who received a newer generation ankle device compared with 72% if undergoing ankle fusion. Continued long-term follow-up studies are necessary, but total ankle arthroplasty has become a viable option for surgical treatment of ankle arthritis.

  20. LED Device Illuminates New Path to Healing

    Science.gov (United States)

    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).

  1. High-power LEDs for plant cultivation

    Science.gov (United States)

    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.

  2. High Efficiency Driving Electronics for General Illumination LED Luminaires

    Energy Technology Data Exchange (ETDEWEB)

    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.

  3. From image quality to atmosphere experience: how evolutions in technology impact experience assessment

    Science.gov (United States)

    Heynderickx, Ingrid; de Ridder, Huib

    2013-03-01

    Image quality is a concept that for long very well served to optimize display performance and signal quality. New technological developments, however, forced the community to look into higher-level concepts to capture the full experience. Terms as naturalness and viewing experience were used to optimize the full experience of 3D-displays and Ambilight TV. These higher-level concepts capture differences in image quality and differences in perceived depth or perceived viewing field. With the introduction of solid-state lighting, further enhancing the multimedia experience, yet more advanced quality evaluation concepts to optimize the overall experience will be needed in the future.

  4. Hawai'i's EVolution: Hawai'i Powered. Technology Driven. (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2013-05-01

    This Hawaii Clean Energy Initiative (HCEI) brochure outlines Hawaii's energy and transportation goals and the implementation of electric vehicles (EV) and electric vehicle infrastructure since HCEI began in 2008. It includes information about Hawaii's role in leading the nation in available EV charging infrastructure per capita; challenges for continuing to implement EV technology; features on various successful EV users, including the Hawaiian Electric Company, Enterprise Rent-A-Car, and Senator Mike Gabbard; how EVs can integrate into and help propel Hawaii's evolving smart grid; and much more.

  5. On the spectral quality of scanner illumination with LEDs

    Science.gov (United States)

    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.

  6. Patterns of technology evolution in SMES in their relationship with MMCS : new challenges in the user-producer relationship in the portuguese context

    OpenAIRE

    Moreira,António Carrizo

    2003-01-01

    This paper is part of a broader study about international production taking into account the relationships between Portuguese Small and Medium-sized firms (SMEs) and foreign multinationals (MNCs). Its importance lies in the complementary linkage MNCs exercise on SMEs. This paper addresses and analyses the patterns of technology evolution in the relationship between SMEs and their MNC clients. The objective is to analyse the technology accumulation process among suppliers as a result of th...

  7. Evolution of the NOAA National Weather Service Satellite Broadcast Network (SBN) to Europe's DVB-S satellite communications technology standard

    Science.gov (United States)

    Cragg, Phil; Brockman, William E.

    2006-08-01

    The National Oceanic and Atmospheric Administration's (NOAA) National Weather Service (NWS) uses a commercial Satellite Broadcast Network (SBN) to distribute weather data to the NWS AWIPS workstations and National Centers and to NWS Family of Service Users. Advances in science and technology from NOAA's observing systems, such as remote sensing satellites and NEXRAD radars, and advances in Numeric Weather Prediction have greatly increased the volume of data to be transmitted via the SBN. The NOAA-NWS SBN Evolution Program did a trade study resulting in the selection of Europe's DVB-S communication protocol as the basis for enabling a significant increase in the SBN capacity. The Digital Video Broadcast (DVB) group, started to develop digital TV for Europe through satellite broadcasting, has become the current standard for defining technology for satellite broadcasting of digital data for much of the world. NOAA-NWS implemented the DVB-S with inexpensive, Commercial Off The Shelf receiving equipment. The modernized NOAA-NWS SBN meets current performance goals and provides the basis for continued future expansion with no increase in current communication costs. This paper discusses aspects of the NOAA-NWS decision and the migration to the DVB-S standard for its commercial satellite broadcasts of observations and Numerical Weather Prediction data.

  8. Low-Cost Illumination-Grade LEDs

    Energy Technology Data Exchange (ETDEWEB)

    Epler, John [Philips Lumileds Lighting Company LLC, San Jose, CA (United States)

    2013-08-31

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

  9. Artificial intelligence and exponential technologies business models evolution and new investment opportunities

    CERN Document Server

    Corea, Francesco

    2017-01-01

    Artificial Intelligence is a huge breakthrough technology that is changing our world. It requires some degrees of technical skills to be developed and understood, so in this book we are going to first of all define AI and categorize it with a non-technical language. We will explain how we reached this phase and what historically happened to artificial intelligence in the last century. Recent advancements in machine learning, neuroscience, and artificial intelligence technology will be addressed, and new business models introduced for and by artificial intelligence research will be analyzed. Finally, we will describe the investment landscape, through the quite comprehensive study of almost 14,000 AI companies and we will discuss important features and characteristics of both AI investors as well as investments. This is the “Internet of Thinks” era. AI is revolutionizing the world we live in. It is augmenting the human experiences, and it targets to amplify human intelligence in a future not so distant from...

  10. Celebrity-led Development Organisations

    DEFF Research Database (Denmark)

    Budabin, Alexandra Cosima; Rasmussen, Louise Mubanda; Richey, Lisa Ann

    2017-01-01

    The past decade has seen a frontier open up in international development engagement with the entrance of new actors such as celebrity-led organisations. We explore how such organisations earn legitimacy with a focus on Madonna’s Raising Malawi and Ben Affleck’s Eastern Congo Initiative. The study...... for funding, endorsements, and expertise. We argue that the ways in which celebrity-led organisations establish themselves as legitimate development actors illustrate broader dynamics of the machinery of development....

  11. Practical lighting design with LEDs

    CERN Document Server

    Lenk, Ron

    2016-01-01

    The second edition of Practical Lighting Design with LEDs has been revised and updated to provide the most current information for developing light-emitting diodes products. The authors, noted authorities in the field, offer a review of the most relevant topics including optical performance, materials, thermal design, and modeling and measurement. Comprehensive in scope, the text covers all the information needed to design LEDs into end products.

  12. LED minilidar for Mars rover

    Science.gov (United States)

    Shiina, Tatsuo; Yamada, Sonoko; Senshu, Hiroki; Otobe, Naohito; Hashimoto, George; Kawabata, Yasuhiro

    2016-10-01

    A mini-lidar to observe the activity of Martian atmosphere is developed. The 10cm-cube LED mini-lidar was designed to be onboard a Mars rover. The light source of the mini-lidar is a high powered LED of 385nm. LED was adopted as light source because of its toughness against circumference change and physical shock for launch. The pulsed power and the pulse repetition frequency of LED beam were designed as 0.75W (=7.5nJ/10ns) and 500kHz, respectively. Lidar echoes were caught by the specially designed Cassegrain telescope, which has the shorter telescope tube than the usual to meet the 10cm-cube size limit. The high-speed photon counter was developed to pursue to the pulse repetition frequency of the LED light. The measurement range is no shorter than 30m depending back-ground condition. Its spatial resolution was improved as 0.15m (=1ns) by this photon counter. The demonstrative experiment was conducted at large wind tunnel facility of Japan Meteorological Agency. The measurement target was smoke of glycerin particles. The smoke was flowed in the wind tunnel with wind speed of 0 - 5m. Smoke diffusion and its propagation due to the wind flow were observed by the LED mini-lidar. This result suggests that the developed lidar can pursue the structure and the motion of dust devil of >2m.

  13. Technological evolution of main critical processes used in COMPERJ; Evolucao tecnologica dos principais processos criticos utilizados no COMPERJ

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Roberta A. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Escola de Quimica; Construtora Norberto Odebrecht, Rio de Janeiro, RJ (Brazil); Seidl, Peter; Guimaraes, Maria Jose O.C. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Escola de Quimica

    2008-07-01

    Considered key to the country, the Petrochemical Complex in Rio de Janeiro (COMPERJ) will provide significant benefits to the Brazilian industry, such as production, a large-scale petrochemical raw materials, due to bigger and better processing of heavy oil national, especially the field of Marlim. The deployment of this complex aggregate value to the national economy, due to replace the export of heavy oil, lower market value, the export of products of higher added value to be produced in the complex. The integration refining-petrochemistry that occur in COMPERJ facilitate critical processes, such as atmospheric distillation, vacuum distillation, Petrochemical FCC and polymerization processes. This venture will take in the same plant, a Basic Petrochemical Unit (UPB) and a number of Petrochemical Associates units (UPA's), where in the first generation, the UPB will produce ethylene and propylene and in the second generation, the UPA's will convert the basic petrochemical in resins such as polypropylene, polyethylene, styrene, among others. The technology of PETROBRAS in relation to processes cited previously, has made many progress in recent years and the result of this development can be seen by increasing of patent number in the technical area. The analysis of technological evolution of these processes is of extreme importance for the identification of innovation trends of Brazil in relation to other countries to confirm the great potential of the Research Center of PETROBRAS with regard to these processes. Thus, this work aims to make an analysis of the technological developments of the main critical processes that will occur in COMPERJ and their integration refining-petrochemistry, identifying the various innovations regarding these processes. (author)

  14. From the water wheel to turbines and hydroelectricity. Technological evolution and revolutions

    Science.gov (United States)

    Viollet, Pierre-Louis

    2017-08-01

    Since its appearance in the first century BC, the water wheel has developed with increasing pre-industrial activities, and has been at the origin of the industrial revolution for metallurgy, textile mills, and paper mills. Since the nineteenth century, the water wheel has become highly efficient. The reaction turbine appeared by 1825, and continued to undergo technological development. The impulsion turbine appeared for high chutes, by 1880. Other turbines for low-head chutes were further designed. Turbine development was associated, after 1890, with the use of hydropower to generate electricity, both for industrial activities, and for the benefits of cities. A model ;one city + one plant; was followed in the twentieth century by more complex and efficient schemes when electrical interconnection developed, together with pumped plants for energy storage.

  15. Automated selection of LEDs by luminance and chromaticity coordinate

    CERN Document Server

    Fischer, Ulrich H P; Reinboth, Christian

    2010-01-01

    The increased use of LEDs for lighting purposes has led to the development of numerous applications requiring a pre-selection of LEDs by their luminance and / or their chromaticity coordinate. This paper demonstrates how a manual pre-selection process can be realized using a relatively simple configuration. Since a manual selection service can only be commercially viable as long as only small quantities of LEDs need to be sorted, an automated solution suggests itself. This paper introduces such a solution, which has been developed by Harzoptics in close cooperation with Rundfunk Gernrode. The paper also discusses current challenges in measurement technology as well as market trends.

  16. Old scissors to industrial automation: the impact of technologic evolution on worker's health.

    Science.gov (United States)

    Teodoroski, Rita de Cassia Clark; Koppe, Vanessa Mazzocchi; Merino, Eugênio Andrés Díaz

    2012-01-01

    To cut a fabric, the professional performs different jobs and among them stands out the cut. The scissors has been the instrument most used for this activity. Over the years, technology has been conquering its space in the textile industry. However, despite the industrial automation able to offer subsidies to answer employment market demands, without appropriate orientation, the worker is exposed to the risks inherent at the job. Ergonomics is a science that search to promote the comfort and well being in consonance with efficacy. Its goals are properly well defined and clearly guide the actions aimed at transforming the working conditions. This study aimed to analyze the activity of cut tissues with a machine by a seamstress and the implications on their body posture. The methodology used was the observation technique and application of the Protocol RULA, where the result obtained was the level 3 and score 5, confirming that "investigations and changes are required soon". Conclude that using the machine to tissue cut should be encouraged, but in conjunction with orientations for improving posture while handling it. It seeks to prevent dysfunction of the musculoskeletal system that prevents employees from performing their work tasks efficiently and productively.

  17. Computer-automated evolution of an X-band antenna for NASA's Space Technology 5 mission.

    Science.gov (United States)

    Hornby, Gregory S; Lohn, Jason D; Linden, Derek S

    2011-01-01

    Whereas the current practice of designing antennas by hand is severely limited because it is both time and labor intensive and requires a significant amount of domain knowledge, evolutionary algorithms can be used to search the design space and automatically find novel antenna designs that are more effective than would otherwise be developed. Here we present our work in using evolutionary algorithms to automatically design an X-band antenna for NASA's Space Technology 5 (ST5) spacecraft. Two evolutionary algorithms were used: the first uses a vector of real-valued parameters and the second uses a tree-structured generative representation for constructing the antenna. The highest-performance antennas from both algorithms were fabricated and tested and both outperformed a hand-designed antenna produced by the antenna contractor for the mission. Subsequent changes to the spacecraft orbit resulted in a change in requirements for the spacecraft antenna. By adjusting our fitness function we were able to rapidly evolve a new set of antennas for this mission in less than a month. One of these new antenna designs was built, tested, and approved for deployment on the three ST5 spacecraft, which were successfully launched into space on March 22, 2006. This evolved antenna design is the first computer-evolved antenna to be deployed for any application and is the first computer-evolved hardware in space.

  18. Advances in NSAID development: evolution of diclofenac products using pharmaceutical technology.

    Science.gov (United States)

    Altman, Roy; Bosch, Bill; Brune, Kay; Patrignani, Paola; Young, Clarence

    2015-05-01

    Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID) of the phenylacetic acid class with anti-inflammatory, analgesic, and antipyretic properties. Contrary to the action of many traditional NSAIDs, diclofenac inhibits cyclooxygenase (COX)-2 enzyme with greater potency than it does COX-1. Similar to other NSAIDs, diclofenac is associated with serious dose-dependent gastrointestinal, cardiovascular, and renal adverse effects. Since its introduction in 1973, a number of different diclofenac-containing drug products have been developed with the goal of improving efficacy, tolerability, and patient convenience. Delayed- and extended-release forms of diclofenac sodium were initially developed with the goal of improving the safety profile of diclofenac and providing convenient, once-daily dosing for the treatment of patients with chronic pain. New drug products consisting of diclofenac potassium salt were associated with faster absorption and rapid onset of pain relief. These include diclofenac potassium immediate-release tablets, diclofenac potassium liquid-filled soft gel capsules, and diclofenac potassium powder for oral solution. The advent of topical formulations of diclofenac enabled local treatment of pain and inflammation while minimizing systemic absorption of diclofenac. SoluMatrix diclofenac, consisting of submicron particles of diclofenac free acid and a proprietary combination of excipients, was developed to provide analgesic efficacy at reduced doses associated with lower systemic absorption. This review illustrates how pharmaceutical technology has been used to modify the pharmacokinetic properties of diclofenac, leading to the creation of novel drug products with improved clinical utility.

  19. [Evolution of food science and technology in developing countries during the last 50 years].

    Science.gov (United States)

    Bressani, R

    1993-01-01

    Malnutrition affects mostly the low-income groups, especially children and pregnant and nursing women despite the advances made in food processing techniques in the last 50 years. Malnutrition is more severe in rural areas of Latin America than big cities. The Institute of Food Science and Technology and the International League for Education and Nutrition of the US in 1976 initiated a study about identifying the actions that could be taken into account for developing countries and donating agencies. The problem of malnutrition in the developing has been evident in these 50 years in terms of deficiencies of protein, iodine, iron, vitamin A, and lack of information concerning proper nutrition during pregnancy and the lactation period. The problem of lack of food was supposed to be solved by the green revolution, which developed cereals with better quality protein using hybrids like triticale (rye and wheat). The population problem with the increase of younger people presents the issue of new jobs and vocations such as professions in nutrition and science. The economic problem is rooted in the dilemma of ¿selling at a low price and buying at a high price¿. The problem of human resources entails the involvement of people in all phases of food production in the developing world.

  20. The Evolution of External Beam Radiation Therapy (EBRT) from a Technological Perspective.

    Science.gov (United States)

    Detorie, Nicholas

    2008-03-01

    Since the discovery of x-rays by Roentgen in 1895 ionizing radiations have been used as a treatment for cancer. Such treatments have been based on either implantation of radioactive materials at the site of disease or by aiming external radiation beams at the diseased site. This later method is referred to as teletherapy because the beams originate from a location outside of the body distant from the disease site itself. A brief review of the basic radiation biology will be given to illustrate the rationale for therapeutic use of ionizing radiations and the effects of beam energy and beam type- particulate or photon. The remainder of the presentation will focus on the technological teletherapy developments supported by the required physical properties of the beams and their associated characteristics that make them suitable for patient treatments. Chronological highlights will include the following sources or devices: superficial x-rays, orthovaltage x-rays, megavoltage x-rays and Cobalt 60 photons, electron beams, neutron beams, negative pi mesons, protons, and heavy ions. The presentation will illustrate how the physical beam properties have been incorporated into modern radiation treatment devices, many of which are equipped with radiation imaging capability. Such devices include: linacs equipped with multileaf collimators for beam shaping and intensity modulation, the Gamma Knife for precise and accurate irradiation of brain tumors or arterial-venous malformations (AVM), the robotic arm based Cyber Knife, and the Helical Tomotherapy unit.

  1. Evaluation of OLED and edge-lit LED lighting panels

    Science.gov (United States)

    Mou, Xi; Narendran, Nadarajah; Zhu, Yiting; Freyssinier, Jean Paul

    2016-09-01

    Solid-state lighting (SSL) offers a new technology platform for lighting designers and end-users to illuminate spaces with low energy demand. Two types of SSL sources include organic light-emitting diodes (OLEDs) and light-emitting diodes (LEDs). OLED is an area light source, and its primary competing technology is the edge-lit LED panel. Generally, both of these technologies are considered similar in shape and appearance, but there is little understanding of how people perceive discomfort glare from large area light sources. The objective of this study was to evaluate discomfort glare for the two lighting technologies under similar operating conditions by gathering observers' reactions. The human factors study results showed no statistically significant difference in human response to discomfort glare between OLED and edge-lit LED panels when the two light sources produced the same lighting stimulus. This means both technologies appeared equally glary beyond a certain luminance.

  2. Linkages between NAMA - LEDS - MRV

    DEFF Research Database (Denmark)

    Agyemang-Bonsu, William; Benioff, Ron; Cox, Sadie

    Low Emission Development Strategies (LEDS), Nationally Appropriate Mitigation Actions (NAMAs) and Monitoring, Reporting and Verification (MRV) are three of the key conceptual components emerging as part of the global architecture for a new climate agreement by 2015. The three components are devel......Low Emission Development Strategies (LEDS), Nationally Appropriate Mitigation Actions (NAMAs) and Monitoring, Reporting and Verification (MRV) are three of the key conceptual components emerging as part of the global architecture for a new climate agreement by 2015. The three components...... how the three components are conceptually interlinked. Identifying the linkages can inform the work on each component and strengthen coordination of work in the context of the three big partnerships; the International Partnership on Mitigation and MRV, the LEDS Global Partnership and the NAMA...

  3. Impurity Influence on Nitride LEDs

    Directory of Open Access Journals (Sweden)

    O.I. Rabinovich

    2014-07-01

    Full Text Available Light emitting diodes (LEDs are widely used nowadays. They are used in major parts of our life. But it is still necessary to improve their characteristics. In this paper the impurity and Indium atoms influence on the LEDs characteristics is investigated by computer simulation. Simulation was carried out in Sim Windows. The program was improved for this purpose by creating new files for AlGaInN heterostructure and devices including more than 25 basic parameters. It was found that characteristics depend on impurity and indium atoms changes a lot. The optimum impurity concentration for doping barriers between quantum wells was achieved. By varying impurity and Indium concentration the distribution in AlGaInN heterostructure LEDs characteristics could be improved.

  4. New Processing of LED Phosphors

    OpenAIRE

    Toda, Kenji

    2012-01-01

    In order to synthesize LED phosphor materials, we have applied three novel synthesis techniques, “melt synthesis”, “fluidized bed synthesis” and “vapor-solid hybrid synthesis”, in contrast with the conventional solid state reaction technique. These synthesis techniques are also a general and powerful tool for rapid screening and improvements of new phosphor materials.

  5. Multicolor, High Efficiency, Nanotextured LEDs

    Energy Technology Data Exchange (ETDEWEB)

    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.

  6. Web网络模型演化下的信息技术%Information Technology Under Web Model Evolution

    Institute of Scientific and Technical Information of China (English)

    沈思

    2011-01-01

    Web model has been developed almost in a decade. The development of currently mobile web brings the new term - web 4.0, in order to improve the mobility architecture of internet and temporal dynamic. We bdefly describe the world of web evolution according to key technologies and application in each period. We also list some points of view about current trend and future direction of web.%Web模型每一代发展都经历了短短不到十年。当前逐步形成的Web4.0网络模型,着重于网络的移动性和信息时间的动态性。本文按照关键技术的出现顺序,回顾并总结各阶段不同的网络模型及其特点.并对下一代网络模型中信息处理技术提出了分析和展望。

  7. The evolution of an e-book demand-driven acquisition programme at Swinburne University of Technology

    Directory of Open Access Journals (Sweden)

    Tony Davies

    2017-07-01

    Full Text Available In 2006 Swinburne University of Technology became the first library in the world to launch a large-scale implementation of a demand-driven acquisition (DDA programme for e-books. At that time, the 34,000 e-books made available through the EBL DDA programme accounted for almost all the e-books available from the Library. In the intervening years the demand-driven collection has grown to almost 300,000 e-books but these now form only a component of a much larger collection of 765,000 e-books in total, acquired through a range of acquisition models. When changes in publisher charging models caused a large increase in short-term loan-based DDA expenditure from late 2014, the library took action during 2015 to put the DDA programme on a sustainable footing. Further changes were introduced in 2016 when Swinburne became one of the launch customers for a new DDA model developed for ProQuest’s Ebook Central platform called Access-to-Own (ATO. This paper describes the evolution of DDA at Swinburne and the early experiences of using the new ATO model.

  8. 网站架构演变技术研究%Research on the Website Architecture Evolution Technology

    Institute of Scientific and Technical Information of China (English)

    张建超; 张连堂

    2012-01-01

    The solution is applied in Website architecture, it directly determines the Website of the availability, load capacity and concurrency. Starting from the Website evolution, by studying the related technology required in developing Website, gives a high performance Website framework from the application point of view on solving the high load and high concurrency problems, the site development faces.%网站架构过程中采取的方案,直接决定其可用性、负载能力以及并发性能。从网站演变脉络入手,通过研究网站开发时所需要的相关技术。从应用的角度探讨解决网站面临的高负载和高并发问题的方法,给出一种综合性能较高的网站构架方案。

  9. Molecular Evolution in Historical Perspective.

    Science.gov (United States)

    Suárez-Díaz, Edna

    2016-12-01

    In the 1960s, advances in protein chemistry and molecular genetics provided new means for the study of biological evolution. Amino acid sequencing, nucleic acid hybridization, zone gel electrophoresis, and immunochemistry were some of the experimental techniques that brought about new perspectives to the study of the patterns and mechanisms of evolution. New concepts, such as the molecular evolutionary clock, and the discovery of unexpected molecular phenomena, like the presence of repetitive sequences in eukaryotic genomes, eventually led to the realization that evolution might occur at a different pace at the organismic and the molecular levels, and according to different mechanisms. These developments sparked important debates between defendants of the molecular and organismic approaches. The most vocal confrontations focused on the relation between primates and humans, and the neutral theory of molecular evolution. By the 1980s and 1990s, the construction of large protein and DNA sequences databases, and the development of computer-based statistical tools, facilitated the coming together of molecular and evolutionary biology. Although in its contemporary form the field of molecular evolution can be traced back to the last five decades, the field has deep roots in twentieth century experimental life sciences. For historians of science, the origins and consolidation of molecular evolution provide a privileged field for the study of scientific debates, the relation between technological advances and scientific knowledge, and the connection between science and broader social concerns.

  10. High performance LED lamps for the automobile: needs and opportunities

    Science.gov (United States)

    Pohlmann, Wolfgang; Vieregge, Thomas; Rode, Martin

    2007-09-01

    Light emitting diodes have been an option in automotive lighting for more than 15 years now. The capacities and colours of LEDs available in the recent past were sufficient to realize interior lighting and rear signalling functions. In the meantime, series applications, such as position or daytime running lights, using white LEDs for signal functions in headlamps, are no longer a rarity. The next step - realizing main lighting functions for series applications - is imminent. LED will offer a multitude of styling options in rear and front lighting, as well as a light colour which differs considerably from that of the previous halogen and xenon headlamp systems. The further advantages of the LED compared with conventional light sources with regard to service life, power efficiency and package space requirements can thus only be sensibly exploited by means of suitable structural and connection techniques. Increasing complexity and installation conditions in an often rough environment are demanding challenge to realize the hardware of LED lamps. In this paper at first the requirements on LEDs and LED modules in automotive exterior lighting will be discussed. Furthermore the status of industrialization and modular concepts for signal lamps and full LED headlamps will be presented. The paper will finish with a discussion of new headlamp active lighting functions like maker light or glare free high beam, implemented in hybrid or with pure LED technology. In the subsequent headlamp integration, from about 2012, freely-addressable LED-Arrays will possibly enable these new types of lighting functions.

  11. Influence of Fluorescent Glue Packaging Technology on the Color Rendering Index of High Power LED%大功率LED荧光胶封装工艺对其显色性能的影响

    Institute of Scientific and Technical Information of China (English)

    钟传鹏

    2009-01-01

    通过大量试验,探索了荧光粉分层封装和荧光粉混合封装的不同荧光胶封装工艺对大功率白光LED显色性能的影响.通过甄选荧光粉、硅胶以及配比,制备出显色指数(CRI)为95的高亮度、低衰减的大功率白光LED.

  12. LED lamp color control system and method

    Science.gov (United States)

    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.

  13. LED lamp power management system and method

    Science.gov (United States)

    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.

  14. SOI LEDs with carrier confinement

    NARCIS (Netherlands)

    Hoang, T.; Holleman, J.; Schmitz, Jurriaan

    2008-01-01

    Silicon-On-Insulator (SOI) technology exhibits significant performance advantages over conventional bulk silicon technology in both electronics and optoelectronics. In this chapter we present an overview of recent applications on light emission from SOI materials. Particularly, in our work we used

  15. Radiometry of flashing LED sources

    Science.gov (United States)

    Gregory, Don A.; Medley, Stephanie; Roberts, Adam

    2008-08-01

    A laboratory based technique has been devised for measuring the illumination characteristics of flashing light emitting diode (LED) sources. The difference between the photopic measurement of a continuous source and a flashing source is that some analytic method must be incorporated into the measurement to account for the response of the eye. Ohno et al have devised an analytic expression for the impulse response of the eye, which closely matches existing forms used for finding effective intensity1. These other forms are the Blondel-Rey equation, the Form Factor method, and the Allard method.4,5,6 Ohno's research suggests a modified Allard method, but offers no procedure for actually making the measurement. In this research, the modified Allard1 method approach has been updated using standard laboratory equipment such as a silicon detector in conjunction with a digital multi-meter and Labview® software to make this measurement. Labview® allows exact computation of the modified Allard method. However, an approximation scheme for the conversion from radiometric units to photopic units must be adopted. The LED spectral form is approximately a Gaussian line shape with full width at half maximum of about 15 to 30nm. The Gaussian curve makes converting from radiometric to photopic units difficult. To simplify, the technique presented here estimates the spectral form of the LEDs to be a Dirac delta function situated at the peak wavelength. This allows the conversion from watts to lumens to be a simple application of the luminous efficiency curve.2 For LEDs with a full width half maximum of 20nm, this scheme is found to be accurate to +/- 5%.

  16. Research on application of infrared thermal imager temperature measurement technology of LED lamp%LED灯具红外热成像温度测量技术应用研究

    Institute of Scientific and Technical Information of China (English)

    张灵改

    2016-01-01

    温度是LED灯具高品质、长寿命、高可靠性等优点显现的关键影响因素,温度测量在LED灯具开发过程中至关重要。分析当前几种主要温度测量方法的优缺点,重点展现红外热像仪的优势;研究影响红外热成像温度测量的环境温度、表面辐射率和测量距离等因素,提高测量精度度。研究结果表明,在红外热像仪使用方法准确的情况下,测量结果极为准确,可缩短灯具开发过程中温度测量时间和提高测量结果准确性,对灯具开发设计具有重要帮助。%The temperature is the key factors affecting the LED Lamps longevity of life, high quality and reliability etc. LED lamps. Temperature measurement in LED lighting development process is rather vital. The analysis of the advantages and disadvantages of the current several kinds of main methods of temperature measurement, especially shows the advantages of infrared thermal imager; study on the influence factors of the infrared thermal imaging temperature measurement of environmental temperature, surface emissivity and measurement distance, aiming at increasing the measurement accuracy. The results of the practical study show that, when the infrared thermal camera using in an accurate way, the measurement result is very accurate, it can shorten the temperature measuring time of lamp development process and improve the accuracy of measurement results, it is of great help to the development and design of lamps and lanterns.

  17. Energy perspectives of France by 2020-2050. Technological evolutions; Perspectives energetiques de la France a l'horizon 2020-2050. Evolutions technologiques

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-09-15

    The different technologies in phase of research and development and concerning the energy production or storage, are examined and presented in function of their probability of emergence at the industrial level: the projects which are going to appear in planed time on the market, the projects based on known technologies which should appear but at non predicted date and the possible projects but based on a new technology. The different type of energy, from the fossil fuels to the renewable energies are concerned. (A.L.B.)

  18. MobiLED: mobile-led and leading via mobile

    CSIR Research Space (South Africa)

    Ford, M

    2009-03-01

    Full Text Available ” of these devices. MobilED (Mobile EDucation) started as a 3-year initiative in 2006 which aimed to take advantage of the cell phone as the only effective technology device in the hands of African children and youth. Although cell phones currently do not play...-and-SMS-only models through to multimedia and smartphones; 2. GSM/GPRS/3G/Bluetooth communication channels; 3. Wikipedia: The Free Encyclopedia; 4. Social Software: MediaWiki, blogs; instant messaging; 5. Open Source Language technologies: Speech interfaces...

  19. A Lifetime Prediction Method for LEDs Considering Real Mission Profiles

    DEFF Research Database (Denmark)

    Qu, Xiaohui; Wang, Huai; Zhan, Xiaoqing

    2017-01-01

    The Light-Emitting Diode (LED) has become a very promising alternative lighting source with the advantages of longer lifetime and higher efficiency than traditional ones. The lifetime prediction of LEDs is important to guide the LED system designers to fulfill the design specifications...... and to benchmark the cost-competitiveness of different lighting technologies. However, the existing lifetime data released by LED manufacturers or standard organizations are usually applicable only for some specific temperature and current levels. Significant lifetime discrepancies may be seen in the field...... properties of the life data available from accelerated degradation testing. The electrical and thermal characteristics of LEDs are measured by a T3Ster system, used for the electro-thermal modeling. It also identifies key variables (e.g., heat sink parameters) that can be designed to achieve a specified...

  20. A lifetime prediction method for LEDs considering mission profiles

    DEFF Research Database (Denmark)

    Qu, Xiaohui; Wang, Huai; Zhan, Xiaoqing

    2016-01-01

    Light-Emitting Diodes (LEDs) has become a very promising alternative lighting source with the advantages of longer lifetime and higher efficiency than traditional ones. The lifetime prediction of LEDs is important to guide the LED system designers to fulfill the design specifications...... and to benchmark the cost-competitiveness of different lighting technologies. The existing lifetime data released by LED manufacturers or standard organizations are usually applicable only for specific temperature and current levels. Significant lifetime discrepancies may be observed in field operations due...... available from accelerated degradation testing. It identifies also the key variables (e.g., heat sink parameters and lifetime-matching of LED drivers) that can be designed to achieve a specified lifetime and reliability level. Two case studies of an indoor residential lighting and an outdoor street lighting...

  1. Future Solid State Lighting using LEDs and Diode Lasers

    DEFF Research Database (Denmark)

    Petersen, Paul Michael

    2014-01-01

    significant savings. Solid state lighting (SSL) based on LEDs is today the most efficient light source for generation of high quality white light. Diode lasers, however, have the potential of being more efficient than LEDs for the generation of white light. A major advantage using diode lasers for solid state...... diodes (LEDs). Blue emitting 445-460 nm LED chips with conversion in phosphorescent materials have undergone tremendous development in the last decade with ultra high efficiencies. However, the technology suffers from a decrease in efficiency at high input current densities, known as the “efficiency...... and non-radiative recombination could be the origins. Recently, Auger recombination was proposed as the dominant mechanism for efficiency droop. In the talk we discuss the mechanisms of the efficiency droop in LEDs and we show how this problem can be eliminated in laser diodes. With the introduction...

  2. Spectral design of new dynamic LED light sources

    DEFF Research Database (Denmark)

    Thorseth, Anders

    The use of LED technology in lighting applications, termed Solid State Lighting, is increasing drastically these years due to increasing flux and efficiency of LED components. The advantages of using Solid State Lighting is not only energy savings but the possibility to create new dynamic light...... sources that can be varied in color temperature and achieving color rendering properties. New LED light sources are constructed as clusters of colored LEDs. Modeling and optimization of the control of the light from the individual LEDs is a necessity for the desired operation of the new dynamic light...... source. Detailed knowledge of the spectral power distribution as a function of operating current and temperature is required for the modeling and optimization. Examples of new high color quality dynamic white light sources that can be tuned from warm white light at 2700 K to cold white light at 6500 K...

  3. Automated platform for determination of LEDs spatial radiation pattern

    Science.gov (United States)

    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

  4. Technological Revolutions and the Evolution of Industrial Structures: Assessing the Impact of New Technologies upon the Size and Boundaries of Firms

    National Research Council Canada - National Science Library

    Dosi, Giovanni; Gambardella, Alfonso; Grazzi, Marco; Orsenigo, Luigi

    2008-01-01

    .... Drawing both on firm-level and national statistical data we assess the evolution of the overall balances between the activities which are integrated within organizations and those which occur through...

  5. Low Cost Heart Rate Monitor Using Led-Led Sensor

    Directory of Open Access Journals (Sweden)

    Ahmed Mahrous Ragib

    2009-01-01

    Full Text Available A high sensitivity, low power and low cost sensor has been developed for photoplethysmography (PPG measurement. The PPG principle was applied to follow the dilatation and contraction of skin blood vessels during the cardiac cycle. A standard light emitting diodes (LEDs has been used as a light emitter and detector, and in order to reduce the space, cost and power, the classical analogue-to-digital converters (ADCs replaced by the pulse-based signal conversion techniques. A general purpose microcontroller has been used for the implementation of measurement protocol. The proposed approach leads to better spectral sensitivity, increased resolution, reduction in cost, dimensions and power consumption. The basic sensing configuration presented is capable of detecting the PPG signal from a finger or toe, and it is very simple to extract the heart rate and heart rate variability from such a signal.

  6. Human development, heredity and evolution.

    Science.gov (United States)

    Nishinakamura, Ryuichi; Takasato, Minoru

    2017-06-15

    From March 27-29 2017, the RIKEN Center for Developmental Biology held a symposium entitled 'Towards Understanding Human Development, Heredity, and Evolution' in Kobe, Japan. Recent advances in technologies including stem cell culture, live imaging, single-cell approaches, next-generation sequencing and genome editing have led to an expansion in our knowledge of human development. Organized by Yoshiya Kawaguchi, Mitinori Saitou, Mototsugu Eiraku, Tomoya Kitajima, Fumio Matsuzaki, Takashi Tsuji and Edith Heard, the symposium covered a broad range of topics including human germline development, epigenetics, organogenesis and evolution. This Meeting Review provides a summary of this timely and exciting symposium, which has convinced us that we are moving into the era of science targeted on humans. © 2017. Published by The Company of Biologists Ltd.

  7. LED Systems Target Plant Growth

    Science.gov (United States)

    2010-01-01

    To help develop technologies for growing edible biomass (food crops) in space, Kennedy Space Center partnered with Orbital Technologies Corporation (ORBITEC), of Madison, Wisconsin, through the Small Business Innovation Research (SBIR) program. One result of this research was the High Efficiency Lighting with Integrated Adaptive Control (HELIAC) system, components of which have been incorporated into a variety of agricultural greenhouse and consumer aquarium lighting features. The new lighting systems can be adapted to a specific plant species during a specific growth stage, allowing maximum efficiency in light absorption by all available photosynthetic tissues.

  8. An investigation on LED customer’ behavior

    Directory of Open Access Journals (Sweden)

    Samaneh Sadat Khoramgah

    2013-03-01

    Full Text Available The recent advances in technology have created a challenge for customer on purchasing electronic devises since the cycle of media production such as TV, Mobile devices, etc. are getting short and people need to replace them by new products. The recent emerge of Light Emitting Diode (LED television has attracted many people and there is a concern to study the impact of important factors on customer behavior in this business. This paper presents an empirical study to study the effects of six variables including customer perception, motivation, cognitive learning, attitude, information and price on customer behavior for LED televisions produced by an Iranian firm in Tehran, Iran. The study designs a questionnaire consists of 27 questions and distributes it among some people who are potential customers of this product. We use multiple regression analysis to study the behavior of different factors on customer behavior. The results of our survey indicate that cognitive learning had the most influencing impact (0.22 on customer behavior followed by price (0.219, motivation (0.203, attitude (0.193, information (0.183 and perception (0.145.

  9. LED--panacea or marketing hype?

    Science.gov (United States)

    Baillie, Jonathan

    2012-02-01

    With energy efficiency and carbon reduction, and the importance of a relaxing, therapeutic patient environment, ever more in the spotlight, LED lighting's proponents claim the technology offers healthcare estates personnel many of the answers on both fronts. However some observers believe its benefits are being over-sold, often to the detriment of other high-performing types of more 'conventional lighting', and to a sometimes uninitiated audience too easily swayed by slick sales patter. HEJ editor Jonathan Baillie spoke to one highly experienced lighting professional, Nicholas Bukorović, a former employee of Thorn, Cooper, and Thorlux Lighting, and the principal author of the last CIBSE/Society of Light and Lighting (SLL) Guide LG2 on healthcare lighting, to seek some expert illumination.

  10. Description and process evaluation of pharmacists' interventions in a pharmacist-led information technology-enabled multicentre cluster randomised controlled trial for reducing medication errors in general practice (PINCER trial)

    Science.gov (United States)

    Howard, Rachel; Rodgers, Sarah; Avery, Anthony J; Sheikh, Aziz

    2014-01-01

    Objective To undertake a process evaluation of pharmacists' recommendations arising in the context of a complex IT-enabled pharmacist-delivered randomised controlled trial (PINCER trial) to reduce the risk of hazardous medicines management in general practices. Methods PINCER pharmacists manually recorded patients' demographics, details of interventions recommended, actions undertaken by practice staff and time taken to manage individual cases of hazardous medicines management. Data were coded, double-entered into SPSS version 15 and then summarised using percentages for categorical data (with 95% confidence interval (CI)) and, as appropriate, means (± standard deviation) or medians (interquartile range) for continuous data. Key findings Pharmacists spent a median of 20 min (interquartile range 10, 30) reviewing medical records, recommending interventions and completing actions in each case of hazardous medicines management. Pharmacists judged 72% (95% CI 70, 74; 1463/2026) of cases of hazardous medicines management to be clinically relevant. Pharmacists recommended 2105 interventions in 74% (95% CI 73, 76; 1516/2038) of cases and 1685 actions were taken in 61% (95% CI 59, 63; 1246/2038) of cases; 66% (95% CI 64, 68; 1383/2105) of interventions recommended by pharmacists were completed and 5% (95% CI 4, 6; 104/2105) of recommendations were accepted by general practitioners (GPs), but not completed at the end of the pharmacists' placement; the remaining recommendations were rejected or considered not relevant by GPs. Conclusions The outcome measures were used to target pharmacist activity in general practice towards patients at risk from hazardous medicines management. Recommendations from trained PINCER pharmacists were found to be broadly acceptable to GPs and led to ameliorative action in the majority of cases. It seems likely that the approach used by the PINCER pharmacists could be employed by other practice pharmacists following appropriate training. PMID

  11. LED lighting for greenhouses. Final report; LED belysning til vaeksthuse. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    OEstergaard, J.E. (Syddansk Univ. (SDU). Erhvervsinnovation og Teknologi, Odense (Denmark))

    2011-01-15

    The project had 3 main objectives: 1) To develop a prototype of a LED-based luminaire that can replace the existing glasshouse horticultural lighting. The project have developed a working prototype and experimentally replaced the traditional HPS luminaires in a controlled growing area. The project succeeded in producing plants of comparable quality. However, the project shows that the prototype can be improved by: x) being further integrated into the existing horticultural production technology (eg climate computers and purchase of electricity) x) adapting configuration of luminaires specifically to each plant variety x) adapting different cooling technologies to match specific customer needs x) In some cases being combined with heat input to optimize the overall economy. 2) To achieve an effective electricity savings of 50-80% - equivalent to a value of approx. DKK 5 million for a medium sized nursery. The verified electricity savings was 40%. In test setups and in well defined and controllable production areas the prototypes achieved electricity savings of > 50%. It is expected that a new generation of LEDs (Q3 2010) will allow for greater power savings. 3) To continue prototype development and initiate commercialization of the project through the company Fionia Lighting A/S. The shareholders of the company have allocated capital to the company to allow us to address the main challenges in commercializing the technology. It is expected that the company will enter a strategic alliance with a major industrial player in the beginning of 2011. (Author)

  12. Current State of the Art in High Brightness LEDs

    Science.gov (United States)

    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

  13. The Victoria West: earliest prepared core technology in the Acheulean at Canteen Kopje and implications for the cognitive evolution of early hominids.

    Science.gov (United States)

    Li, Hao; Kuman, Kathleen; Lotter, Matt G; Leader, George M; Gibbon, Ryan J

    2017-06-01

    Prepared core technology illustrates in-depth planning and the presence of a mental template during the core reduction process. This technology is, therefore, a significant indicator in studying the evolution of abstract thought and the cognitive abilities of hominids. Here, we report on Victoria West cores excavated from the Canteen Kopje site in central South Africa, with a preliminary age estimate of approximately 1 Ma (million years ago) for these cores. Technological analysis shows that the Victoria West cores bear similarities to the 'Volumetric Concept' as defined for the Levallois, a popular and widely distributed prepared core technology from at least 200 ka (thousand years ago). Although these similarities are present, several notable differences also occur that make the Victoria West a unique and distinctive prepared core technology; these are: elongated and convergent core shapes, consistent blow directions for flake removal, a predominance of large side-struck flakes, and the use of these flakes to make Acheulean large cutting tools. This innovative core reduction strategy at Canteen Kopje extends the roots of prepared core technology to the latter part of the Early Acheulean and clearly demonstrates an increase in the cognitive abilities and complexities of hominids in this time period.

  14. III-nitride monolithic LED covering full RGB color gamut

    Science.gov (United States)

    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.

  15. LED-ID System: Coverage And Fast Link Recovery Technique

    Directory of Open Access Journals (Sweden)

    Muhammad Shahin Uddin

    2012-11-01

    Full Text Available Recently Light Emitting Diodes (LEDs are considered to represent the next generation of lighting and communication technology. LED-ID (Light Emitting Diode – Identification is one of the key technologies for identification, data transmission and illumination simultaneously. This is the new paradigm in theidentification technology environment. LED-ID system typically needs line of sight (LOS to support narrow FOV transceivers links to achieve high data rate but reduced the coverage, increase the disconnection rate of the link. Also when the receiver moves horizontally or vertically, in that case coverage also varied and LOS relies upon direct link between transmitter and receiver. Link recovery is a new challenge for reliable LED-ID system. Fast link recovery techniques are essential for the making the system robust. In this paper we discuss about the horizontal and vertical coverage variation in terms of received power and fast link recovery technique for the LED-ID system considering both LOS and NLOS reflection.

  16. Designing low cost LED display for the billboard

    Science.gov (United States)

    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.

  17. GATEWAY Demonstrations: Philadelphia International Airport Apron Lighting: LED System Performance in a Trial Installation

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Robert G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wilkerson, Andrea M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-10-30

    This report documents a trial installation of LED apron lighting that replaced the existing high-pressure sodium luminaires at Philadelphia International Airport. Such high-mast applications remain challenging for LED technology, and the lessons learned from this project may help facility managers and LED product manufacturers better meet those challenges.

  18. The Evolution Research of Mobile Cellular Communication Technology for IoT%移动蜂窝物联网演进方案研究

    Institute of Scientific and Technical Information of China (English)

    邢宇龙; 张力方; 胡云

    2016-01-01

    物联网应用中,低速率业务占比超过了50%。以NB-IoT和LTE-eMTC为代表的低功耗广域蜂窝技术在低功耗、广覆盖业务中扮演着重要角色。对物联网通信技术的分类和演进路线进行了阐述,介绍了NB-IoT和LTE-eMTC 2种典型的蜂窝通信技术的标准进展,最后给出了中国联通物联网的演进策略和蜂窝物联网的部署方案。%More than half of the IoT applications are low data-rate business. Low power wide area(LPWA)cel ular technologies,such as NB-IoT and LTE-eMTC,play an important role in low-power and wide-coverage application. It firstly describes the classifica-tion and the evolution route of IoT communication technology,then introduces the standardization progress of NB-IoT and LTE-eMTC,which are two typical cel ular communication technologies. Final y,it analyzes the IoT evolution strategy of China Unicom and presents the deployment schemes of cel ular IoT.

  19. Optics designs for an innovative LED lamp family system

    Science.gov (United States)

    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.

  20. Fluorescent silicon carbide materials for white LEDs and photovoltaics

    DEFF Research Database (Denmark)

    Syväjärvi, Mikael; Ou, Haiyan; Wellmann, Peter

    Energy efficient materials solutions will be key figures in progressive energy saving applications. We explore a materials growth concept of fluorescent wide bandgap semiconductors for white and infrared LEDs as well as solar cells. This is an emerging scientific field which has not previously been...... explored. The applications include a white LED for general lighting in which the conversion is based on the semiconductor instead of using phosphors. The result is an LED technology which does not need rare earth metals and has a pure white light. In efficient fluorescent materials, the absorption may...... the luminescence appears in the visible region which is used to produce a white LED with pure white light without need of phosphors [2]. The cubic silicon carbide polytype is challenging to master, and we have explored the growth of this crystal structure. It has a lower bandgap, and by a similar doping concept...

  1. Malaria over-diagnosis in Cameroon: diagnostic accuracy of Fluorescence and Staining Technologies (FAST) Malaria Stain and LED microscopy versus Giemsa and bright field microscopy validated by polymerase chain reaction.

    Science.gov (United States)

    Parsel, Sean M; Gustafson, Steven A; Friedlander, Edward; Shnyra, Alexander A; Adegbulu, Aderosoye J; Liu, Ying; Parrish, Nicole M; Jamal, Syed A; Lofthus, Eve; Ayuk, Leo; Awasom, Charles; Henry, Carolyn J; McArthur, Carole P

    2017-04-04

    Malaria is a major world health issue and its continued burden is due, in part, to difficulties in the diagnosis of the illness. The World Health Organization recommends confirmatory testing using microscopy-based techniques or rapid diagnostic tests (RDT) for all cases of suspected malaria. In regions where Plasmodium species are indigenous, there are multiple etiologies of fever leading to misdiagnoses, especially in populations where HIV is prevalent and children. To determine the frequency of malaria infection in febrile patients over an 8-month period at the Regional Hospital in Bamenda, Cameroon, we evaluated the clinical efficacy of the Flourescence and Staining Technology (FAST) Malaria stain and ParaLens Advance(TM) microscopy system (FM) and compared it with conventional bright field microscopy and Giemsa stain (GS). Peripheral blood samples from 522 patients with a clinical diagnosis of "suspected malaria" were evaluated using GS and FM methods. A nested PCR assay was the gold standard to compare the two methods. PCR positivity, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were determined. Four hundred ninety nine samples were included in the final analysis. Of these, 30 were positive via PCR (6.01%) with a mean PPV of 19.62% and 27.99% for GS and FM, respectively. The mean NPV was 95.01% and 95.28% for GS and FM, respectively. Sensitivity was 26.67% in both groups and specificity was 92.78% and 96.21% for GS and FM, respectively. An increased level of diagnostic discrepancy was observed between technicians based upon skill level using GS, which was not seen with FM. The frequency of malarial infections confirmed via PCR among patients presenting with fever and other symptoms of malaria was dramatically lower than that anticipated based upon physicians' clinical suspicions. A correlation between technician skill and accuracy of malaria diagnosis using GS was observed that was less pronounced using FM

  2. Energy savings by implementation of light quality LED lighting. Final report; Implementering af energibesparelser ved benyttelse af hoejkvalitets LED belysning. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    Dam-Hansen, C.; Thorseth, A.; Poulsen, Peter

    2010-03-15

    The project developed two new LED light sources and systems, emphasising the potential of LED technology for energy savings and lighting quality. A LED light source for display case lighting, replacing incandescent lamps, was successfully installed in the Treasury at Rosenborg Castle in Copenhagen, Denmark, and it was decided to extend the solution in 2010. Electricity savings of 74% were achieved. LED light sources replacing halogen bulbs in cooker hoods reduce electricity consumption by 69% and ensure even lighting of the entire working surface with about 500 lux at all cooking areas. Furthermore, a new LED optics system was patented. (ln)

  3. Research on Disruptive Technology and Evolution of its Market Competition%突破性技术及其市场竞争演化研究

    Institute of Scientific and Technical Information of China (English)

    孙圣兰; 宁钟

    2015-01-01

    Market is the carrier of value realization of technology innovation activities , so the market is the power producer of the survival and development of the enterprises' innovation and the beginning and ending of technology innovation. Based on the market segmentation theory, economic of scale theory, industrial theory and marginal utility theory, this paper analyzes the evolution of market competition of disruptive technology and mainstream technology, and discusses the effect of consumers' demand diversity on disruptive technology, and reveals the action mechanism of disruptive technology on the generation of mainstream technology as well as the effect of different types of consumers on the transformation of disruptive technology to mainstream technology in the market. By using the value analysis method, this paper establishes the consumers purchase decision model, and discusses the effect factors and conditions that the disruptive technology threatens the mainstream technology as well as the effect of different types of consumers' demand on the evolution and implementation conditions of disruptive technology. At the end, the paper discusses the implications and future direction of research so as to make the study on radical technology innovation to be more deep , systematic and perfect and better promote the great-leap-forward development of Chinese technology and the rapid growth of the whole economy.%市场是技术创新活动价值实现的载体。因此,市场既是企业实现技术创新赖以生存和发展的动力源泉,也是技术创新的起点和终点。文章基于细分市场理论、规模经济理论、产业理论以及边际理论等相关理论,对突破性技术与主流技术的市场竞争演化以及消费者需求的差异性对突破性技术创新的不同作用进行了研究,报告了突破性技术对市场上的主流技术产生的作用机理以及不同类型的消费者对突破性技术创新转变为市场上的

  4. Technology.

    Science.gov (United States)

    Online-Offline, 1998

    1998-01-01

    Focuses on technology, on advances in such areas as aeronautics, electronics, physics, the space sciences, as well as computers and the attendant progress in medicine, robotics, and artificial intelligence. Describes educational resources for elementary and middle school students, including Web sites, CD-ROMs and software, videotapes, books,…

  5. LED rear combination lamps: styling, robustness, life, packaging, installation, and opportunities for intelligent signal lighting

    Science.gov (United States)

    Eberle, Stefan; Livschitz, Leonard; Raggio, Jeffrey

    2005-02-01

    The automotive industry is rapidly increasing the adoption of LED technology in all vehicle lighting applications. In the near future, LED solutions are expected to capture significant market share for exterior signal lighting. This paper will investigate why LED signal lighting is important to automotive OEMs and consumers, and will exhibit how the latest product development from Lumileds Lighting can enable the ultimate RCL application: a single LED instead of a conventional light bulb.

  6. Goniometric characterization of LED based greenhouse lighting

    DEFF Research Database (Denmark)

    Thorseth, Anders; Lindén, Johannes; Corell, Dennis Dan

    2015-01-01

    This paper describes a demonstration of goniospectroradiometry for characterizations of new light emitting diode (LED) based luminaries for enhanced photosynthesis in greenhouses. It highlights the differences between measurement of the traditional high pressure sodium (HPS) luminaries and the LED...

  7. Fokusgruppeinterview som led i en evalueringsproces

    DEFF Research Database (Denmark)

    Andersen-Mølgaard, Hanna; Harrit, Ole

    2006-01-01

    Teoretiske begrundelser og perspektiver, responsiv-konstruktivistisk evaluering, fokusgruppeinterview som led i BIKVAmodellen, eksempler, vurdering og perspektivering......Teoretiske begrundelser og perspektiver, responsiv-konstruktivistisk evaluering, fokusgruppeinterview som led i BIKVAmodellen, eksempler, vurdering og perspektivering...

  8. Metallic nanostructures for efficient LED lighting

    NARCIS (Netherlands)

    Lozano, G.; Rodriguez, S. R. K.; Verschuuren, M. A.; Rivas, Gomez

    2016-01-01

    Light-emitting diodes (LEDs) are driving a shift toward energy-efficient illumination. Nonetheless, modifying the emission intensities, colors and directionalities of LEDs in specific ways remains a challenge often tackled by incorporating secondary optical components. Metallic nanostructures suppor

  9. Essentials for Successful and Widespread LED Lighting Adoption

    Science.gov (United States)

    Khan, Nisa

    2011-03-01

    Solid-state lighting (SSL), with light-emitting diodes (LEDs) as the light source, is a growing and essential field, particularly in regard to the heightened need for global energy efficiency. In recent years, SSL has experienced remarkable advances in efficiency, light output magnitude and quality. Thus such diverse applications as signage, message centers, displays, and special lighting are now adopting LEDs, taking 2010's market to 9.1 billion - 68% growth from the previous year! While this is promising, future growth in both display and lighting applications will rely upon unveiling deeper understanding and key innovations in LED lighting science and technologies. In this presentation, some LED lighting fundamentals, engineering challenges and novel solutions will be discussed to address reduction in efficiency (a.k.a. droop) at high currents, and to obtain uniform light distribution for overcoming LEDs' directional nature. The droop phenomenon has been a subject of much controversy in the industry and despite several studies and claims, a widely-accepted explanation still lacks because of counter arguments and experiments. Recently several research studies have identified that the droop behavior in nitride-based LEDs beyond certain current density ranges can only be comprehensively explained if the current leaking beyond the LED active region is included. Although such studies have identified a few useful current leakage mechanisms outside the active region, no one has included current leakage, due to non-ideal, 3-D device structures that create undesirable current distribution inside and outside the active region. This talk will address achieving desirable current distributions from optimized 3-D device structures that should reduce current leakage and hence the droop behavior. In addition to novel LED design solutions for droop reduction and uniform light distribution, the talk will address cost and yield concerns as they pertain to core material scarcity

  10. LOW-COST LED LUMINAIRE FOR GENERAL ILLUMINATION

    Energy Technology Data Exchange (ETDEWEB)

    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.

  11. INTERIM REPORT ON THE EVOLUTION AND PERFORMANCE OF THE EICHROM TECHNOLOGIES PROCEPT RAPID DIOXIN ASSAY FOR SOIL AND SEDIMENT SAMPLES

    Science.gov (United States)

    A demonstration of screening technologies for determining the presence of dioxin and dioxin-like compounds in soil and sediment was conducted under the U.S. Environmental Protection Agency's(EPA's) Superfund Innovative Technology Evaluation Program in Saginaw, Michigan in 2004. T...

  12. Proceedings of the 2nd workshop on linking aspect technology and evolution, Bonn, Germany, 20.03.2006

    NARCIS (Netherlands)

    Tourwé, T.; Shepherd, D.; Kellens, A.; Ceccato, M.

    2006-01-01

    Software evolution lies at the heart of the software development process, and suffers from problems such as maintainability, evolvability, understandability, etc. Aspect-oriented software development (AOSD) is an emerging software development paradigm, that tries to achieve better separation of conc

  13. Development of LED light sources and lamps. Final report; Slutrapport for PSO 337-068. Udvikling af LED lyskilder og lamper

    Energy Technology Data Exchange (ETDEWEB)

    Dam-Hansen, C.; Petersen, Paul Michael; Thestrup, B.; Scharling Holm, J.; Munkgaard Andersen, J.; Falleboe, H.; Olsen, Jesper; Flindt, C.

    2007-04-15

    This report is the final and concluding report on the research and development project 'Development of LED light sources and lamps' PSO no. 337-068 supported by Dansk Energi - Net. The project was a collaboration between Risoe National laboratory, Louis Poulsen Lighting, Dong Energy, Laboratoriet Lys & Syn and RGB Lamps. The objective of this project was to pave the way for replacement of incandescent- and halogen lighting by LED lightning through development of prototypes for new types of LED products: light sources and lamps. The report summarizes and describes the main results of the project, which are: 1) a new LED light source with an efficacy of 51 lm/W and a CRI index of 92 that can replace an incandescent bulb. 2) two LED pendants/lamps, a LED table lamp and a chair with LED lighting developed by designers and researchers. 3) LED seminar and two exhibitions of the newly developed LED products and user test by questionnaires. 4) A new startup company 'Morfoso'. 5) Developed course on light and LED technology for designers. 6) A new LED light laboratory for test and characterization of LED components and LED light sources and lamps. (au)

  14. Thermal Design for 5 Watt Power LED

    Institute of Scientific and Technical Information of China (English)

    WANG Cai-feng; NIU Ping-juan; GAO Tie-cheng; YANG Guang-hua; FU Xian-song

    2009-01-01

    With the consideration of the thermal management and heat sink requirements, a cooling device is designed and the thermal resistance of this device is calculated with a single 5 W power LED. The thermal design of a single 5 W power LED is reasonable, effective and the result has been simulated. This design also instruct other power LEDs' thermal design. Provided is a reliable and effective method for the design of power LED illumination lamps and lanterns.

  15. ‘No Blue’ White LED

    DEFF Research Database (Denmark)

    Ou, Haiyan; Corell, Dennis Dan; Dam-Hansen, Carsten

    2010-01-01

    This paper explored the feasibility of making a white LED light source by color mixing method without using the blue color. This ‘no blue’ white LED has potential applications in photolithography room illumination, medical treatment and biophotonics research. A no-blue LED was designed, and the p...

  16. PENGEMBANGAN LAMPU LED DENGAN TEKNOLOGI PHOTOVOLTAIC (LED-PV SEBAGAI ALAT BANTU PENGUMPUL IKAN PADA PERIKANAN BAGAN

    Directory of Open Access Journals (Sweden)

    Mochamad Arief Sofijanto

    2015-03-01

    mengetahui perbedaan jumlah hasil tangkapan pada bagan tancap akibat perlakuan warna lampu LED yang berbeda. Metode penelitian yang digunakan adalah deskriptif dan experimental fishing dimana rancangan penelitiannya adalah Rancangan Acak Lengkap (RAL dengan perlakuan warna lampu LED sebanyak 5 jenis warna yaitu merah (A, kuning (B, hijau (C, biru (D, dan putih (E dengan 6 kali ulangan. Secara deskriptif hasil penelitian menunjukkan lampu LED dapat digunakan untuk menggantikan lampu petromaks dan lampu LHE. Diperoleh 17 jenis ikan laut yang tertarik pada cahaya lampu LED yang digunakan. Hasil analisis statistik menunjukkan terdapat perbedaan nyata terhadap hasil tangkapan bagan dengan perlakuan warna lampu LED. Berdasarkan Uji Nyata Terkecil dinyatakan bahwa bagan yang menggunakan warna lampu LED biru mendapatkan hasil tangkapan tertinggi kemudian diikuti oleh warna kuning, hijau, putih dan merah.  The set ‘bagan’ (liftnet fishing gear is a kind of fishing gears which using atificial light as fishes gathering. This fishing gear uses an electric generator to turn on the energy saving lamp which hang on under the set ‘bagan’. The price of gasoline more expensive due to the Indonesia government’s fuel subsidy reduced and this make fishing operation costs more expensive for fishermen. This research using the LED lamps that do not use gasoline as fuel because the LED lamps can use the photovoltaic technology (solar cell system. The purposes of this study were: 1 to find out whether the LED lamps can replace the kerosene lamps and saving energy lamps, 2 to know the different in cath using different colours of LED lamps. The reserach methods are descriptive and experimental fishing which used Completely Randomized Design with LED lamps colour treatments i.e: red (A, yellow (B, green (C, blue (D, and white (E, the number of replications are 6 times. LED lamps can be used to replace the kerosene and saving energy lamps. There were 17 species of

  17. 信息技术用户接受理论及其演变%Information Technology Theory of User Acceptance and Evolution

    Institute of Scientific and Technical Information of China (English)

    阳瑾瑜

    2015-01-01

    信息技术用户接受理论起源于心理学领域的理性行为理论,经历了理性行为理论、规划行为理论、技术接受模型、社会认知理论、技术—任务适配模型、创新扩散理论等理论演变,在综合相关理论模型的基础之上,又提出了整合型技术接受和使用理论及其模型,为有效推进信息化进程提供了理论工具。%Information technology theory of user acceptance originates from the theory of rational behavior in the field of psychology,and has experienced evolutions of the theory of reasoned action,theory of planned behavior,technology acceptance model,social cognitive theory,task-technology fit model,innovation diffusion theory,etc. Based on the related theoretical overview,a new theory—unified theory of acceptance and applicatain technology and model is put forward. This paper will provide a theoretical tool to effectively promote the informationization process.

  18. The LED outdoor lighting revolution : Opportunities, threats and mitigation

    Science.gov (United States)

    Aube, Martin

    2017-01-01

    The presence of artificial light at night (ALAN) in environment is now known to have non negligible consequences on the night sky, the fauna, the flora and the human health. A real revolution is undergoing in the outdoor lighting industry threatens the night integrity. This revolution is driven by the advent of the cost-effective Light-Emitting Diode (LED) technology into the outdoor lighting industry. The LEDs provides many opportunities: they are long lasting, easily controlled, and generally allow a more efficient photometric design which, in term, may result in energy savings.After explaining the complex and non-linear behaviour of the propagation of the ALAN into the nocturnal environment, we will outline the potential impact of the ALAN on the human health and on the night sky, and we will introduce some dedicated indicators for its evaluation. We will focus on the role of the blue content of the ALAN in the evaluation of its impact. More specifically we will show how white LED technology, that often shows increased blue light content, compares to the traditional High Pressure Sodium technology. Finally, we will identify the possible mitigations to restrict the adverse impacts of the white LEDs in the urban and rural environment.

  19. A New Way to Introduce Microarray Technology in a Lecture/Laboratory Setting by Studying the Evolution of This Modern Technology

    Science.gov (United States)

    Rowland-Goldsmith, Melissa

    2009-01-01

    DNA microarray is an ordered grid containing known sequences of DNA, which represent many of the genes in a particular organism. Each DNA sequence is unique to a specific gene. This technology enables the researcher to screen many genes from cells or tissue grown in different conditions. We developed an undergraduate lecture and laboratory…

  20. High quality Danish design with intelligent LED light. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, Paul Michael; Dam-Hansen, C.; Thestrup, B.; Pedersen, Henrik (Technical Univ. of Denmark, DTU Fotonik, Roskilde (Denmark)); Olsen, Jesper (JesperOlsen ApS, Frederiksberg (Denmark)); Falleboe, H.; Andersen, Jakob (MORFOSO, Copenhagen (Denmark))

    2010-02-15

    Based on the results achieved in a previous project, which enabled a number of designers to be trained in the potential of LED lighting technology, this project developed intelligent LED fixtures for work purposes and for private homes. The two types of fixtures both meet the original project objective of good colour rendition with Ra indices above 90 and colour temperatures variable within the interval 3,300 to 4,400 K. Furthermore, with luminous efficacies of 60 lumen/W, both fixtures have energy efficiencies exceeding that of an average energy-friendly light source. (ln)

  1. The Digitalisation of Social Representations : The Influence of the Evolution of Communication Technology on the Development of Shared Ideas

    OpenAIRE

    Wahlström, Mikael

    2012-01-01

    Human mentality is in constant change as new ideas emerge, are challenged, become concrete and are compared to existing concepts in the societal discourse. The theory of social representations is an attempt to explain this process. The study contributes to this field of enquiry by discussing how changes in communication technologies influence the process. New digital communication technologies, such as broadband Internet connections, smartphones, sophisticated Web search engines and similar d...

  2. Beyond Technology Push vs. Demand Pull:The Evolution of Solar Policy in the U.S., Germany and China

    OpenAIRE

    Hansen, Erik Gunnar; Lüdeke-Freund, Florian; Quan, Xiahong; West, Joel

    2015-01-01

    To explain and promote the adoption of new technologies, researchers have debated the relative importance of technology push and demand pull factors (e.g., Schmookler, 1966; Mowery and Rosenberg, 1979; Peters et al, 2012). Here we examine a crucial problem of contemporary innovation policy — promoting the adoption of renewable energy to reduceanthropogenic global warming — that challenges prior models for large scale innovation adoption. From the recommendations of Mowery, Nelson and Martin (...

  3. The evolution of ambulatory ECG monitoring.

    Science.gov (United States)

    Kennedy, Harold L

    2013-01-01

    Ambulatory Holter electrocardiographic (ECG) monitoring has undergone continuous technological evolution since its invention and development in the 1950s era. With commercial introduction in 1963, there has been an evolution of Holter recorders from 1 channel to 12 channel recorders with increasingly smaller storage media, and there has evolved Holter analysis systems employing increasingly technologically advanced electronics providing a myriad of data displays. This evolution of smaller physical instruments with increasing technological capacity has characterized the development of electronics over the past 50 years. Currently the technology has been focused upon the conventional continuous 24 to 48 hour ambulatory ECG examination, and conventional extended ambulatory monitoring strategies for infrequent to rare arrhythmic events. However, the emergence of the Internet, Wi-Fi, cellular networks, and broad-band transmission has positioned these modalities at the doorway of the digital world. This has led to an adoption of more cost-effective strategies to these conventional methods of performing the examination. As a result, the emergence of the mobile smartphone coupled with this digital capacity is leading to the recent development of Holter smartphone applications. The potential of point-of-care applications utilizing the Holter smartphone and a vast array of new non-invasive sensors is evident in the not too distant future. The Holter smartphone is anticipated to contribute significantly in the future to the field of global health.

  4. Generation of solar spectrum by using LEDs

    Science.gov (United States)

    Lu, Pengzhi; Yang, Hua; Pei, Yanrong; Li, Jing; Xue, Bin; Wang, Junxi; Li, Jinmin

    2016-09-01

    Light emitting diode (LED) has been recognized as an applicable light source for indoor and outdoor lighting, city beautifying, landscape facilities, and municipal engineering etc. Conventional LED has superior characteristics such as long life time, low power consumption, high contrast, and wide viewing angle. Recently, LED with high color-rendering index and special spectral characteristics has received more and more attention. This paper is intended to report a solar spectrum simulated by multichip LED light source. The typical solar spectrum of 5500k released by CIE was simulated as a reference. Four types of LEDs with different spectral power distributions would be used in the LED light source, which included a 430nm LED, a 480nm LED, a 500nm LED and a white LED. In order to obtain better simulation results, the white LED was achieved by a 450nm LED chip with the mixture of phosphor. The phosphor combination was prepared by mixing green phosphor, yellow phosphor and red phosphor in a certain proportion. The multichip LED light source could provide a high fidelity spectral match with the typical solar spectrum of 5500k by adjusting injection current to each device. The luminous flux, CIE chromaticity coordinate x, y, CCT, and Ra were 104.7 lm, 0.3337, 0.3681, 5460K, and 88.6, respectively. Because of high color-rendering index and highly match to the solar spectrum, the multichip LED light source is a competitive candidate for applications where special spectral is required, such as colorimetric measurements, visual inspection, gemstone identification and agriculture.

  5. Technology

    Directory of Open Access Journals (Sweden)

    Xu Jing

    2016-01-01

    Full Text Available The traditional answer card reading method using OMR (Optical Mark Reader, most commonly, OMR special card special use, less versatile, high cost, aiming at the existing problems proposed a method based on pattern recognition of the answer card identification method. Using the method based on Line Segment Detector to detect the tilt of the image, the existence of tilt image rotation correction, and eventually achieve positioning and detection of answers to the answer sheet .Pattern recognition technology for automatic reading, high accuracy, detect faster

  6. Evolution of microcomputer-based medical instrumentation.

    Science.gov (United States)

    Tompkins, Willis J

    2009-01-01

    This paper provides a historical review of the evolution of the technologies that led to modern microcomputer-based medical instrumentation. I review the history of the microprocessor-based system because of the importance of the microprocessor in the design of modern medical instruments. I then give some examples of medical instruments in which the microprocessor has played a key role and in some cases has even empowered us to develop new instruments that were not possible before. I include a discussion of the role of the microprocessor-based personal computer in development of medical instruments.

  7. 基于专利引文网络的技术轨道识别研究——以太阳能光伏电池板领域为例%Research on identification of technological evolution path based on patent citation network —— taking solar photovoltaic panels technology as an example

    Institute of Scientific and Technical Information of China (English)

    杨中楷; 刘佳

    2011-01-01

    Using patents and patent citation network to identify technological evolution path. Elaborate the principle of technological evolution path identification, form the algorithm of technological evolution path identification and provide the feasibility of technological evolution path identification as well as its visualization. Identify and map the technological evolution path combining the solar photovoltaic panel data, elaborate main nodes and explore technology evolution history as well as future trends to provide some decision -making reference strategy on the development of related industries in China.%利用专利及其引文网络进行技术轨道识别研究。阐述技术轨道识别的原理,形成技术轨道识别的算法,从理论上提供技术轨道识别及其可视化的可行性。结合太阳能光伏电池板数据,识别并绘制出技术轨道图谱,对主要节点进行重点阐述,探寻技术沿革的历史脉络和未来趋势,对我国相关领域的发展战略提供决策参考。

  8. From road to lab to math: the co-evolution of technological, regulatory, and organizational innovations for automotive crash testing.

    Science.gov (United States)

    Leonardi, Paul M

    2010-04-01

    Today, in the midst of economic crisis, senior executives at US automakers and influential industry analysts frequently reflect on the progression that safety testing has taken from the crude trials done on the road, to controlled laboratory experiments, and to today's complex math-based simulation models. They use stories of this seemingly linear and natural sequence to justify further investment in simulation technologies. The analysis presented in this paper shows that change in the structures of automakers' organizations co-evolved with regulations specifying who was at fault in vehicle impacts, how vehicles should be built to withstand the force of an impact, and how testing should be done to assure that vehicles met those requirements. Changes in the regulatory environment were bolstered by new theories about crash test dynamics and changing technologies with which to test those theories. Thus, as new technological and regulatory innovations co-evolved with innovations in organizational structuring, ideas about how to best conduct crash tests shifted and catalyzed new cycles of technological, regulatory, and organizational innovation. However, this co-evolutionary story tells us that the move from road to lab to math was not natural or linear as today's managerial rhetoric would have us believe. Rather, the logic of math-based simulation was the result of technological, regulatory and organizational changes that created an industry-wide ideology that supported the move toward math while making it appear natural within the shifting structure of the industry.

  9. A brief history of LED photopolymerization.

    Science.gov (United States)

    Jandt, Klaus D; Mills, Robin W

    2013-06-01

    The majority of modern resin-based oral restorative biomaterials are cured via photopolymerization processes. A variety of light sources are available for this light curing of dental materials, such as composites or fissure sealants. Quartz-tungsten-halogen (QTH) light curing units (LCUs) have dominated light curing of dental materials for decades and are now almost entirely replaced by modern light emitting diode light curing units (LED LCUs). Exactly 50 years ago, visible LEDs were invented. Nevertheless, it was not before the 1990s that LEDs were seriously considered by scientists or manufactures of commercial LCUs as light sources to photopolymerize dental composites and other dental materials. The objective of this review paper is to give an overview of the scientific development and state-of-the-art of LED photopolymerization of oral biomaterials. The materials science of LED LCU devices and dental materials photopolymerized with LED LCU, as well as advantages and limits of LED photopolymerization of oral biomaterials, are discussed. This is mainly based on a review of the most frequently cited scientific papers in international peer reviewed journals. The developments of commercial LED LCUs as well as aspects of their clinical use are considered in this review. The development of LED LCUs has progressed in steps and was made possible by (i) the invention of visible light emitting diodes 50 years ago; (ii) the introduction of high brightness blue light emitting GaN LEDs in 1994; and (iii) the creation of the first blue LED LCUs for the photopolymerization of oral biomaterials. The proof of concept of LED LCUs had to be demonstrated by the satisfactory performance of resin based restorative dental materials photopolymerized by these devices, before LED photopolymerization was generally accepted. Hallmarks of LED LCUs include a unique light emission spectrum, high curing efficiency, long life, low energy consumption and compact device form factor. By

  10. Self-aligning LED-based optical link

    Science.gov (United States)

    Shen, Thomas C.; Drost, Robert J.; Rzasa, John R.; Sadler, Brian M.; Davis, Christopher C.

    2016-09-01

    The steady advances in light-emitting diode (LED) technology have motivated the use of LEDs in optical wireless communication (OWC) applications such as indoor local area networks (LANs) and communication between mobile platforms (e.g., robots, vehicles). In contrast to traditional radio frequency (RF) wireless communication, OWC utilizes electromagnetic spectrum that is largely unregulated and unrestricted. OWC communication may be especially useful in RF-denied environments, in which RF communication may be prohibited or undesirable. However, OWC does present some challenges, including the need to maintain alignment between potentially moving nodes. We describe a novel system for link alignment that is composed of a hyperboloidal mirror, camera, and gimbal. The experimental system is able to use the mirror and camera to detect an LED beacon of a neighboring node and estimate its bearing (azimuth and elevation), point the gimbal towards the beacon, and establish an optical link.

  11. Study on the p-type QWIP-LED device

    Institute of Scientific and Technical Information of China (English)

    ZHEN; Honglou; XIONG; Dayuan; ZHOU; Xuchang; LI; Ning; SHAO; Jun; LU; Wei

    2006-01-01

    A p-type quantum well infrared photodetector (QWIP) integrated with a light-emitting diode (LED) (named QWIP-LED) was fabricated and studied. The infrared photo-response spectrum was obtained from the device resistance variation and the near-infrared photo-emission intensity variation. A good agreement between these two spectra was observed, which demonstrates that the long-wavelength infrared radiation around 7.5 μm has been transferred to the near-infrared light at 0.8 μm by the photo-electronic process in the QWIP-LED structure. Moreover, the experimentally observed infrared response wavelength is in good agreement with the theoretical calculation value of 7.7 μm. The results on the upconversion of the infrared radiation will be very useful for the new infrared focal plane array technology.

  12. Evolution of Media Technology and Its Implications%媒介技术的发展演变及其启示

    Institute of Scientific and Technical Information of China (English)

    黄金艳; 王学俭

    2016-01-01

    Abstract From the spoken media, text printed media to the new media driven by electronic technology, the media technology has gone through a long evolution. In this process, on the one hand, emerging media always heritage advantages of the old media and overcome the shortcomings of the old media to complete their own development; on the other hand, the media continuously and imperceptibly impact on human society and human itself. Medium for the dissemination of human technology can plug in information science wings, but apparently, he flew destination information should be the temple of human civilization, rather than a simple technical tool or tool technology workshops. The evolution of media technology only follow instrumental rationality and value rationality unity in order to achieve their healthy development, and better development in order to highlight the people-oriented, scientific development.%从口语媒介、文字印刷媒介到现在由电子技术主导的新新媒介,媒介技术经历了漫长的发展演变。在这个过程中,一方面,新出现的媒介总会传承旧媒介的优势,克服旧媒介的弊端从而完成媒介自身的发展;另一方面,媒介又在不间断地、潜移默化地影响人类社会及人本身。媒介技术能为人类信息的传播插上科学的翅膀,但显然,翅膀飞翔的目的地应是人类信息文明的殿堂,而非简单的技术工具或者工具技术的作坊。媒介技术的发展演变只有遵循工具理性与价值理性的统一,才能实现其健康发展、更好发展,才能凸显以人为本、科学发展。

  13. Thermal Performance Analysis of LED with Multichips

    Institute of Scientific and Technical Information of China (English)

    HAN Yuanyuan; GUO Hong; ZHANG Ximin; YIN Fazhang; CHU Ke; FAN Yeming

    2011-01-01

    The package and system level temperature and thermal stress distributions of 10 W light emitting diode (LED) with 4 chips and 100 W LED with 100 chips were investigated using finite element analysis.The chips were arranged on a Si sheet which is soldered on the copper/diamond composite slug with very high conductivity.The experimental results show that the maximal temperature appears in the chips of both two high power LEDs packages.Compared with the 10 W LEDs package with 4 chips array,the heat issue caused by stacking and coupling of the heat in 100 W LEDs package with 100 chips array is more serious.The chip temperature in the center of the array is much higher,and it decreases with the distance between the chip and the center of LEDs increases.Great thermal stress lies between the chips and the solder,which will reduce the reliability of the package.

  14. High-Voltage LED Light Engine with Integrated Driver

    Energy Technology Data Exchange (ETDEWEB)

    Soer, Wouter [Lumileds LLC, San Jose, CA (United States)

    2016-02-29

    LED luminaires have seen dramatic changes in cost breakdown over the past few years. The LED component cost, which until recently was the dominant portion of luminaire cost, has fallen to a level of the same order as the other luminaire components, such as the driver, housing, optics etc. With the current state of the technology, further luminaire performance improvement and cost reduction is realized most effectively by optimization of the whole system, rather than a single component. This project focuses on improving the integration between LEDs and drivers. Lumileds has developed a light engine platform based on low-cost high-power LEDs and driver topologies optimized for integration with these LEDs on a single substrate. The integration of driver and LEDs enables an estimated luminaire cost reduction of about 25% for targeted applications, mostly due to significant reductions in driver and housing cost. The high-power LEDs are based on Lumileds’ patterned sapphire substrate flip-chip (PSS-FC) technology, affording reduced die fabrication and packaging cost compared to existing technology. Two general versions of PSS-FC die were developed in order to create the desired voltage and flux increments for driver integration: (i) small single-junction die (0.5 mm2), optimal for distributed lighting applications, and (ii) larger multi-junction die (2 mm2 and 4 mm2) for high-power directional applications. Two driver topologies were developed: a tapped linear driver topology and a single-stage switch-mode topology, taking advantage of the flexible voltage configurations of the new PSS-FC die and the simplification opportunities enabled by integration of LEDs and driver on the same board. A prototype light engine was developed for an outdoor “core module” application based on the multi-junction PSS-FC die and the single-stage switch-mode driver. The light engine meets the project efficacy target of 128 lm/W at a luminous flux

  15. High-Voltage LED Light Engine with Integrated Driver

    Energy Technology Data Exchange (ETDEWEB)

    Soer, Wouter [Lumileds LLC, San Jose, CA (United States)

    2016-02-29

    LED luminaires have seen dramatic changes in cost breakdown over the past few years. The LED component cost, which until recently was the dominant portion of luminaire cost, has fallen to a level of the same order as the other luminaire components, such as the driver, housing, optics etc. With the current state of the technology, further luminaire performance improvement and cost reduction is realized most effectively by optimization of the whole system, rather than a single component. This project focuses on improving the integration between LEDs and drivers. Lumileds has developed a light engine platform based on low-cost high-power LEDs and driver topologies optimized for integration with these LEDs on a single substrate. The integration of driver and LEDs enables an estimated luminaire cost reduction of about 25% for targeted applications, mostly due to significant reductions in driver and housing cost. The high-power LEDs are based on Lumileds’ patterned sapphire substrate flip-chip (PSS-FC) technology, affording reduced die fabrication and packaging cost compared to existing technology. Two general versions of PSS-FC die were developed in order to create the desired voltage and flux increments for driver integration: (i) small single-junction die (0.5 mm2), optimal for distributed lighting applications, and (ii) larger multi-junction die (2 mm2 and 4 mm2) for high-power directional applications. Two driver topologies were developed: a tapped linear driver topology and a single-stage switch-mode topology, taking advantage of the flexible voltage configurations of the new PSS-FC die and the simplification opportunities enabled by integration of LEDs and driver on the same board. A prototype light engine was developed for an outdoor “core module” application based on the multi-junction PSS-FC die and the single-stage switch-mode driver. The light engine meets the project efficacy target of 128 lm/W at a luminous flux greater than 4100 lm, a correlated

  16. New paradigms in LED photometry and colorimetry

    Science.gov (United States)

    Estrada-Hernández, A.; González-Galván, L. P.; Rosas, E.

    2009-09-01

    Motivated by the growing number of applications the light emitting diodes, LEDs, are having in solid-state lighting systems, we summarize the new internationally standardized measurement methods for photometric and colorimetric quantities in LEDs; since they are commonly used to quantify some of the key performance parameters of several products used in automotive industry, traffic signaling, etc. Finally, special emphasis is given to the mismatch corrections factors calculation, and its use when measuring LEDs photometric and colorimetric quantities.

  17. System Reliability for LED-Based Products

    Energy Technology Data Exchange (ETDEWEB)

    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.

  18. The Influence of New Technologies on the Evolution of Learning and Attitudes towards Mathematics in Secondary Students

    Science.gov (United States)

    Garcia, Maria del Mar; Romero, Isabel Maria

    2009-01-01

    The present article is part of a study carried out with Secondary School students in Mathematics class. Our research interest lies in exploring the influence of using ICT (Information and Communication Technology) on students' attitudes and on how they learn mathematics, as observed when they are solving contextualized problems. This is a…

  19. Wide reflected angle DBR red light LED

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The coupled DBR LED with one DBR for reflecting normal incidence light and the other for reflecting inclined incidence light has been grown by MOCVD. For improving the conventional DBR which was used to increase light extraction efficiency in A1GaInP red light LED is analyzed. At 20 mA Dc injection current, the LED peak wave length is 630 nm, and the light intensity of on axis is 137 mcd. The output light power is 2.32 mW. The light intensity and output light power have been improved compared with the conventional LEDs.

  20. Projecting LED product life based on application

    Science.gov (United States)

    Narendran, Nadarajah; Liu, Yi-wei; Mou, Xi; Thotagamuwa, Dinusha R.; Eshwarage, Oshadhi V. Madihe

    2016-09-01

    LED products have started to displace traditional light sources in many lighting applications. One of the commonly claimed benefits for LED lighting products is their long useful lifetime in applications. Today there are many replacement lamp products using LEDs in the marketplace. Typically, lifetime claims of these replacement lamps are in the 25,000-hour range. According to current industry practice, the time for the LED light output to reach the 70% value is estimated according to IESNA LM-80 and TM-21 procedures and the resulting value is reported as the whole system life. LED products generally experience different thermal environments and switching (on-off cycling) patterns when used in applications. Current industry test methods often do not produce accurate lifetime estimates for LED systems because only one component of the system, namely the LED, is tested under a continuous-on burning condition without switching on and off, and because they estimate for only one failure type, lumen depreciation. The objective of the study presented in this manuscript was to develop a test method that could help predict LED system life in any application by testing the whole LED system, including on-off power cycling with sufficient dwell time, and considering both failure types, catastrophic and parametric. The study results showed for the LED A-lamps tested in this study, both failure types, catastrophic and parametric, exist. The on-off cycling encourages catastrophic failure, and maximum operating temperature influences the lumen depreciation rate and parametric failure time. It was also clear that LED system life is negatively affected by on-off switching, contrary to commonly held belief. In addition, the study results showed that most of the LED systems failed catastrophically much ahead of the LED light output reaching the 70% value. This emphasizes the fact that life testing of LED systems must consider catastrophic failure in addition to lumen depreciation, and

  1. LED背光源前景看好%There's an LED Backlight in Your Future

    Institute of Scientific and Technical Information of China (English)

    Steve Sechrist

    2006-01-01

    @@ LED backlight solution provider Global Lighting Technologies (GLT) (Brecksville, OH) is going to introduce a new family of LED light guides with plans to demonstrate a 24"(61 cm) LCD-TV with an LED backlight.To understand the significance of this announcement, we have to go back to a presentation given last month at the Strategies in Light (SIL) Conference held in San Francisco. There, Seoul Semiconductor VP, Dr. Jae Jo Kim, listed low efficiency (high cost) as the number one obstacle to large LCD adoption of LED lighting particularly, the number of LEDs required to adequately replace today's cold-cathode fluorescent lamps (CCFLs).

  2. The value, solutions, and costs of patterning LED's

    Science.gov (United States)

    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

  3. Status and prospects for phosphor-based white LED packaging

    Institute of Scientific and Technical Information of China (English)

    Zongyuan LIU; Sheng LIU; Kai WANG; Xiaobing LUO

    2009-01-01

    The status and prospects for high-power, phosphor-based white light-emitting diode (LED) pack-aging have been presented. A system view for packaging design is proposed to address packaging issues. Four aspects of packaging are reviewed: optical control, thermal management, reliability and cost. Phosphor materials play the most important role in light extraction and color control. The conformal coating method improves the spatial color distribution (SCD) of LEDs. High refractive index (RI) encapsulants with high transmittance and modified surface morphology can enhance light extraction. Multi-phosphor-based packaging can realize the control of correlated color temperature (CCT) with high color rendering index (CRI). Effective thermal management can dissipate heat rapidly and reduce thermal stress caused by the mismatch of the coefficient of thermal expansion (CTE). Chip-on-board (COB) technology with a multi-layer ceramic substrate is the most promising method for high-power LED packaging. Low junction temperature will improve the reliability and provide longer life. Advanced processes, precise fabrication and careful operation are essential for high reliability LEDs. Cost is one of the biggest obstacles for the penetration of white LEDs into the market for general illumination products. Mass production in terms of CoB, system in packaging (SIP), 3D packaging and wafer level packaging (WLP) can reduce the cost significantly, especially when chip cost is lowered by using a large wafer size.

  4. Life-Cycle Assessment of Energy and Environmental Impacts of LED Lighting Products, Part 3: LED Environmental Testing

    Energy Technology Data Exchange (ETDEWEB)

    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

  5. Using UAVs to Conduct Student-led Research Projects

    Science.gov (United States)

    Olds, S. E.; Lewis, P. M., Jr.

    2016-12-01

    Recreational drones can inspire students to initiate research projects. These "toys" have a low cost (Arduino board, SABEL collects temperature, humidity, and GPS position. This presentation will provide examples of student-led investigations, instructions for building the SABEL sensor package, and the status of the new e-book compilation of student-focused activities using recreational drones to pursue science, math, engineering, and technology research investigations.

  6. Emotion-on-a-chip (EOC): evolution of biochip technology to measure human emotion using body fluids.

    Science.gov (United States)

    Lee, Jung-Hyun; Hwang, Yoosun; Cheon, Keun-Ah; Jung, Hyo-Il

    2012-12-01

    Recent developments in nano/micro technology have made it possible to construct small-scale sensing chips for the analysis of biological markers such as nucleic acids, proteins, small molecules, and cells. Although biochip technology for the diagnosis of severe physiological diseases (e.g., cancer, diabetes, and cardiovascular disease) has been extensively studied, biochips for the monitoring of human emotions such as stress, fear, depression, and sorrow have not yet been introduced, and the development of such a biochip is in its infancy. Emotion science (or affective engineering) is a rapidly expanding engineering/scientific discipline that has a major impact on human society. The growing interest in the integration of emotion science and engineering is a result of the recent trend of merging various academic fields. In this paper we discuss the potential importance of biochip technology in which human emotion can be precisely measured in real time using body fluids such as blood, saliva, urine, or sweat. We call these biochips emotion-on-a-chip (EOC). The EOC system consists of four parts: (1) collection of body fluids, (2) separation of emotional markers, (3) detection of optical or electrical signals, and (4) display of results. These techniques provide new opportunities to precisely investigate human emotion. Future developments in EOC techniques will combine social and natural sciences to expand their scope of study. Copyright © 2012 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

    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.

  8. LEDs in automotive lighting and signaling: a customer point of view

    Science.gov (United States)

    Berlitz, Stephan; Heider, Christian

    2007-09-01

    The development of brand specific front and tail lights in cooperation with the stylists is the assignment of automobile lighting. Highest car safety, attractive styling, differentiation in the traffic situation and environment friendliness are the project limits. LED technology has the potential to extend these limits. The LED technology will have to improve, but it is also enhanced by new sensor technologies that introduce new functionalities. The implementation of a possible roadmap depends on right technologies at the right time. For new styling ideas and functional innovations further steps in lighting technology are necessary. The document will show a car makers view on possible innovation ideas.

  9. Reduced Component Count RGB LED Driver

    NARCIS (Netherlands)

    De Pedro, I.; Ackermann, B.

    2008-01-01

    The goal of this master thesis is to develop new drive and contrololutions, for creating white light from mixing the light of different-color LEDs, aiming at a reduced component count resulting in less space required by the electronics and lower cost. It evaluates the LED driver concept proposed in

  10. Led Zeppelin reklaamib Narvat / Anti Ronk

    Index Scriptorium Estoniae

    Ronk, Anti

    2007-01-01

    Ilmus Narva-teemaline kahest CD-st koosnev album, kus ühel plaadil on 60 minutit videot linna vaatamisväärsuste ja informatsiooniga, teisel - briti rockansambli Led Zeppelini teosed Narva sümfooniaorkestri ja rockansambli Led R esituses

  11. Led Zeppelin reklaamib Narvat / Anti Ronk

    Index Scriptorium Estoniae

    Ronk, Anti

    2007-01-01

    Ilmus Narva-teemaline kahest CD-st koosnev album, kus ühel plaadil on 60 minutit videot linna vaatamisväärsuste ja informatsiooniga, teisel - briti rockansambli Led Zeppelini teosed Narva sümfooniaorkestri ja rockansambli Led R esituses

  12. Using LEDs to reduce energy consumption

    Science.gov (United States)

    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.

  13. High Performance Green LEDs by Homoepitaxial

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. High Performance Green LEDs by Homoepitaxial

    Energy Technology Data Exchange (ETDEWEB)

    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.

  15. Harmonics Monitoring Survey on LED Lamps

    Directory of Open Access Journals (Sweden)

    Abdelrahman Ahmed Akila

    2017-03-01

    Full Text Available Light Emitting Diode (LED lamps are being increasingly used in many applications. These LED lamps operate using a driver, which is a switching device. Hence, LED lamps will be a source of harmonics in the power system. These harmonics if not well treated, may cause severe performance and operational problems. In this paper, harmonics (amplitude and phase angles generated by both LED lamps and conventional fluorescent lamps will be studied practically. Then they will be analyzed and evaluated. Compared to each other harmonics generated by both LED and conventional florescent lamps, self mitigation may occur based on the phase angle of these harmonics. All data will be measured using power analyzer and will be done on a sample of actual lamps.

  16. Accurate colorimetric feedback for RGB LED clusters

    Science.gov (United States)

    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.

  17. White LEDs with limit luminous efficacy

    Energy Technology Data Exchange (ETDEWEB)

    Lisitsyn, V. M.; Stepanov, S. A., E-mail: stepanovsa@tpu.ru; Yangyang, Ju [National Research Tomsk Polytechnic University, 30 Lenin Av., Tomsk, 634050 (Russian Federation); Lukash, V. S. [JSC Research Institute of Semiconductor Devices, 99a Krasnoarmeyskaja St., Tomsk, 634050 (Russian Federation)

    2016-01-15

    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.

  18. The Impact Of gender On Atttitude Towards Computer Technology And E-Learning: An Exploratary Study of Punjab University,India

    Directory of Open Access Journals (Sweden)

    Dr Gunamala Suri1 , Sneha Sharma2

    2013-04-01

    Full Text Available Technological advancement has led to important changes in the way education is being imparted. Evolution of internet and advancement in computer technology has led to new approaches in learning and training which are referred to as e-Learning. This study aims to understand the relationship between gender and attitude towards e-learning. Literature shows that gender plays a key role in understanding the differences in perception towards usefulness of technology and ease of use but with regards to attitude and perception towards e-learning diverse views have been presented. This paper analyses the effect of gender on attitude towards computer technology and e-learning collectively

  19. The Evolution of Firms'Technological Innovative Capabilities under the Perspective of the Evolution of Knowledge Network and the Policy Recommendations%知识网络演进视角下企业技术创新能力进化及政策建议

    Institute of Scientific and Technical Information of China (English)

    童心; 于丽英

    2015-01-01

    The nature of the development of firms'technological innovative capabilities similar to that of biological evolu‐tion .Based on the idea and the evolution of a knowledge network ,the effect of knowledge network on firms'technological innovative capabilities have been researched ,and the process of evolution of firms'technological innovative capabilities have been discussed .Further ,the logical model of evolution of firms'technological innovative capabilities has been constructed . The results show that the circular evolution of knowledge network promotes the continued evolution of firms'technological innovative capabilities through the mechanism of knowledge acquisition ,knowledge processing ,knowledge sharing and knowledge integration .Finally ,the suggestions for promoting the evolution of firms'technological innovative capabilities have been put forward from the perspective of policy makers and the microscopic innovators ,respectively .%企业技术创新能力具有类生物进化的属性,基于该思想,以知识网络演进为背景,研究了知识网络对企业技术创新能力进化的作用,探讨了企业技术创新能力进化过程,进一步构建了企业创新能力进化的逻辑模型。研究发现,知识网络的循环演进通过知识获取、知识处理、知识共享和知识整合,促进企业技术创新能力不断进化。最后,分别从政策制定者角度和微观创新者角度,提出了促进企业技术创新能力进化的建议。

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

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2008-09-14

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

  1. Remote monitoring of LED lighting system performance

    Science.gov (United States)

    Thotagamuwa, Dinusha R.; Perera, Indika U.; Narendran, Nadarajah

    2016-09-01

    The concept of connected lighting systems using LED lighting for the creation of intelligent buildings is becoming attractive to building owners and managers. In this application, the two most important parameters include power demand and the remaining useful life of the LED fixtures. The first enables energy-efficient buildings and the second helps building managers schedule maintenance services. The failure of an LED lighting system can be parametric (such as lumen depreciation) or catastrophic (such as complete cessation of light). Catastrophic failures in LED lighting systems can create serious consequences in safety critical and emergency applications. Therefore, both failure mechanisms must be considered and the shorter of the two must be used as the failure time. Furthermore, because of significant variation between the useful lives of similar products, it is difficult to accurately predict the life of LED systems. Real-time data gathering and analysis of key operating parameters of LED systems can enable the accurate estimation of the useful life of a lighting system. This paper demonstrates the use of a data-driven method (Euclidean distance) to monitor the performance of an LED lighting system and predict its time to failure.

  2. Impact of the Evolution of Smart Phones in Education Technology and its Application in Technical and Professional Studies: Indian Perspective

    Directory of Open Access Journals (Sweden)

    Manoj Kumar

    2011-09-01

    Full Text Available The greatness of any nation depends largely on the system of education that is used to nurture its talentfrom within. With the digital era taking the spotlight, and the world rapidly reforming into a global village,it is now quintessential that a spirit of healthy competitiveness be inculcated in the budding minds of thiscountry. While trying to remodel and upgrade the education system, a key issue is that of quality ofeducation processes in the country. Needs and expectations of the society are changing very fast and thequality of higher education requires to be sustained at the desired level.The use of internet for educational purposes has increased many folds among Indian youths. Online videolectures and e-books are the emerging trends among learners. The birth of high speed internet access andits availability on recently evolved smart phones has opened several new avenues for learning. Thegrowing popularity of these smart phones among the youth can potentially revolutionize the way we learn.The introduction of 3G technology is already being pinned as the next big thing in the mobile internetrevolution.This paper discusses the use of Smart Phones in Education Technology and its application in Technical &Professional studies in India. We intend to put forward some challenges and advices.

  3. Multi-sensor Evolution Analysis system: how WCS/WCPS technology supports real time exploitation of geospatial data

    Science.gov (United States)

    Natali, Stefano; Mantovani, Simone; Folegani, Marco; Barboni, Damiano

    2014-05-01

    EarthServer is a European Framework Program project that aims at developing and demonstrating the usability of open standards (OGC and W3C) in the management of multi-source, any-size, multi-dimensional spatio-temporal data - in short: "Big Earth Data Analytics". In the third and last year of EarthServer project, the Climate Data Service lighthouse application has been released in its full / consolidated mode. The Multi-sensor Evolution Analysis (MEA) system, the geospatial data analysis tool empowered with OGC standard, has been adopted to handle data manipulation and visualization; Web Coverage Service (WCS) and Web Coverage Processing Service (WCPS) are used to access and process ESA, NASA and third party products. Tenth of Terabytes of full-mission, multi-sensor, multi-resolution, multi-projection and cross-domain coverages are already available to user interest groups belonging Land, Ocean and Atmosphere products. The MEA system is available at https://mea.eo.esa.int. During the live demo, typical test cases implemented by User interest Groups within EarthServer and ESA Image Information Mining projects will be showed with special emphasis on the comparison of MACC Reanalysis and ESA CCI products.

  4. Preliminary investigations of piezoelectric based LED luminary

    DEFF Research Database (Denmark)

    Nielsen, Dennis; Andersen, Michael A. E.; Meyer, Kaspar Sinding

    2011-01-01

    This paper presents a preliminary study of PT (Piezoelectric Transformer) based SMPS’s (Switch Mode Power Supplies) for LED luminary. The unique properties of PTs (efficiency, power density and EMI) make them highly suitable for this application. Power stage topologies, rectifiers circuits......, modulation schemes, LEDs and LED driving conditions are analyzed. A prototype radial mode PT optimized for ZVS (Zero Voltage Switching) is designed. FEM (Final Element Method) and measurements validates the PT design. A prototype PT based AC/DC converter operating from european mains is proposed...

  5. Experimental study of negative capacitance in LEDs

    Institute of Scientific and Technical Information of China (English)

    FENG Lie-feng; WANG Jun; ZHU Chuan-yun; CONG Hong-xia; CHEN Yong; WANG Cun-da

    2005-01-01

    The experimental study on negative capacitance(NC) of various light-emitting diodes(LEDs) is presented.Experimental result shows that all LEDs display the NC phenomenon.The voltage modulated electroluminescence(VMEL) experiment confirms that the reason of negative capacitance is the strong recombination of the injected carriers in the active region of luminescence.The measures also verify that the dependence of NC on voltage and frequency in different LEDs is similar: NC phenomenon is more obvious with higher voltage or lower frequency.

  6. International trade, technological change and evolution of work market; Commercio internazionale, cambiamento tecnologico e mercato del lavoro

    Energy Technology Data Exchange (ETDEWEB)

    Cacciotti, M.

    1999-07-01

    The report estimates the historic series of wages and employment depending on the average unit value of importation prices in the most important european countries, Italy, France and Germany for the years 1988-1996. Results shows that in the traditional sectors, with unskilled employment are negative influenced by international trade, otherwise, in the technological advanced sectors, influenced are to be considered positive. [Italian] Lo studio sottopone a stima le serie storiche dei salari e dell'occupazione in funzione del valore medio unitario dei prezzi alle importazioni per i piu' importanti paesi europei, Italia, Francia, Germania, durante il periodo 1988-1996. I risultati mostrano che per i settori tradizionali, che impiegano manodopera meno qualificata, il commercio internazionel tende ad influenzare negativamente i livelli salariali ed occupazionali, mentre per i settorui tecnologicamente piu' avanzati determina variazioni positive dei salari e dell'occupazioni.

  7. CooLED - efficient LED bulbs with custrom optics - final report

    DEFF Research Database (Denmark)

    Wolff, Jesper; Corell, Dennis Dan; Dam-Hansen, Carsten

    Denne rapport indeholder en beskrivelse af arbejdet udført i og resultaterne af forsknings- og udviklingsprojektet EUDP 64012-0226, CooLED – en ny generation LED Lyskilde for det tidsløse high-end marked.......Denne rapport indeholder en beskrivelse af arbejdet udført i og resultaterne af forsknings- og udviklingsprojektet EUDP 64012-0226, CooLED – en ny generation LED Lyskilde for det tidsløse high-end marked....

  8. MEMS惯性技术的发展及应用%Evolution and application of MEMS inertial technology

    Institute of Scientific and Technical Information of China (English)

    齐广峰; 吕军锋

    2015-01-01

    Micro Electro Mechanical Systems (MEMS) has become a research hotspot of the tactical inertial navigation, and one of the main research directions for future inertial navigation technology. This survey is conducted for the development and application of MEMS inertial navigation. A brief introduction of MEMS inertial sensors is first given, also the development of MEMS inertial system is introduced by the research program of Draper laboratory, then the latest developments of MEMS inertial measurement unit (IMU) and MEMS integrated navigation system has been surveyed, at last the development trend of MEMS inertial system has been summarized. High-performance MEMS gyros, chip scale MEMS-IMU and MEMS integrated system is the development trend of the MEMS inertial technology.%MEMS惯性技术是近年来战术级惯性导航的研究热点,也是惯性导航技术未来的主要发展方向之一。本文介绍了MEMS惯性传感器的发展概况,结合Draper实验室的MEMS惯性系统项目计划介绍了MEMS惯性系统的发展,分别介绍了MEMS惯性测量单元和MEMS组合导航技术的最新进展,并展望了MEMS惯性系统的发展趋势。高性能MEMS陀螺、芯片级MEMS-IMU和MEMS组合导航系统是MEMS惯性技术未来的发展趋势。

  9. Characteristics of spatio-temporal evolution in Beijing land subsidence, 2003-2009, using PS-InSAR technology

    Science.gov (United States)

    Gu, Z.; Gong, H.; Lu, X.; Zhang, Y.; Chen, B.; Liu, H.; Wang, S.

    2013-12-01

    Two thirds of water supply in Beijing city has come from groundwater, surveyed by Beijing Institute of Hydrogeology and Engineering Geology. During the past several years, Beijing city has suffers severe groundwater decline and land subsidence, induced by continuous over-exploitation of groundwater for nearly 60 years. The maximum of subsidence has reached up to 1096mm since 60 decades, and the rates in these subsidence bowls is between 10 mm/yr to 20 mm/yr, and The cumulative subsidence greater than 300mm is up to 1300km2, which pose a great challenge to public infrastructure and mitigate hazard in Beijing municipal. Permanent Scatterers Synthetic Aperture Radar Interferometry (PS-InSAR) can quickly obtain surface deformation details with high resolution, compared to traditional leveling and extensometer techniques. In this paper we use PS-InSAR technique and 29 acquisitions by Envisat between 2003 and 2009 to monitor recent land subsidence in Beijing plain area. we studied the characteristics of spatio-temporal evolution of Beijing subsidence. The results suggests subsidence bowls have been bounded together in Beijing plain area, which covers Chaoyang, Changping, Shunyi, Tongzhou area, and the range of subsidence has a eastward trend. With conventional of emergency water resource in Changping, Huairou, Pinggu, the rates have increased from more than 10-20mm/yr to about 20-30mm/yr, 50 percent increase in subsidence bowls. What's more, the spatial and temporal distribution of deformation is not only controlled by tectonic but influenced by stress-strain behavior (elastic - plastic - viscoelastic) of aquifer systems. Keywords: Land Subsidence; PS-InSAR; Beijing; Ground fissure; Stress-strain analysis

  10. LED til væksthuse

    DEFF Research Database (Denmark)

    Dam-Hansen, Carsten; Thorseth, Anders; Rosenqvist, Eva

    2012-01-01

    Den teknologiske udvikling indenfor Lys Emitterende Dioder (LED) går imod stadig større lysmængder og stadig større effektivitet. Kombineret med fordele som lang levetid, dæmpbarhed og ingen varmestråling gør det, at LED baserede lyskilder/lamper i stigende grad benyttes til belysningsformål og kan...

  11. Computational Techniques for LED Optical Microcavities

    OpenAIRE

    García Santiago, Xavier

    2015-01-01

    The project consist on the development of numerical methods and computational techniques to model the processes of light extraction in power LED (Light-Emitting Diodes) devices. We aim at the use of complex corrugated microstructures to boost the efficiency of our current LUXEON LED products. In order to study extraction efficiency in these devices a 3D optics model of thin film micro-structures must be developed and tested. In this project we develop a numerical model for computing and st...

  12. Investigation of Passive Filter for LED Lamp

    Science.gov (United States)

    Sarwono, Edi; Facta, Mochammad; Handoko, Susatyo

    2017-04-01

    Light Emitting Diode lamp or LED lamp is one of the energy saving lamps nowadays widely used by consumers. However, LED lamp has contained harmonics caused by the rectifier circuit inside the lamp. Harmonics cause a quality problem in power system. As the harmonics present in current or voltage, the waveforms are distorted. Harmonics can lead to overheating in magnetic core of electrical equipments. In this paper, several tests are carried out to investigate the harmonic content of voltage and currents, and also the level of light intensity of the two brands of LED lamps. Measurements in this study are conducted by using HIOKI Power Quality Analyzer 3197. The test results show that the total harmonic distortion or THD of voltage on various brands of LED lamps did not exceed 5% as in compliance to the limit of IEEE standard 519-1992. The largest harmonic voltage is 2.9%, while maximum harmonic current for tested brands of LED lamp is 170.6%. The use of low pass filter in the form of LC filter was proposed. Based on experimental results, the application of LC filter at input side of LED lamp has successfully reduced THD current in the range of 85%-88%.

  13. Null bactericidal effect of ultraviolet radiation emitted by LEDs.

    Directory of Open Access Journals (Sweden)

    Francisco Alcántara Muñoz

    2016-11-01

    Full Text Available This research has aimed to assess the bactericidal effect of ultraviolet light emitted by LEDS on the growth on Petri dishes of microorganisms whose legal limits in foods have been established. An electrically fed apparatus has been designed with precise timing and a camera to prevent light spillage, in which two ultraviolet radiation emission devices were connected by LED technology at different wavelengths: through an array of LEDS emitting at around 350nm, and a single specific emission LED at 280nm. 1000 cfu of E. Coli and S. aureus sown on PCA were used as prototypes of gram negative and positive bacteria, respectively, onto which ultraviolet light was radiated at different time intervals, by means of both devices, with the whole experiment being carried out in triplicate . In none of the three series of treatments at the two wavelengths were reductions in microbial growth observed. The series of sowings on PCA were done on unseeded plates in order to be able to discard the likelihood of subsequent recontamination.

  14. Has Human Evolution Stopped?

    Directory of Open Access Journals (Sweden)

    Alan R. Templeton

    2010-07-01

    Full Text Available It has been argued that human evolution has stopped because humans now adapt to their environment via cultural evolution and not biological evolution. However, all organisms adapt to their environment, and humans are no exception. Culture defines much of the human environment, so cultural evolution has actually led to adaptive evolution in humans. Examples are given to illustrate the rapid pace of adaptive evolution in response to cultural innovations. These adaptive responses have important implications for infectious diseases, Mendelian genetic diseases, and systemic diseases in current human populations. Moreover, evolution proceeds by mechanisms other than natural selection. The recent growth in human population size has greatly increased the reservoir of mutational variants in the human gene pool, thereby enhancing the potential for human evolution. The increase in human population size coupled with our increased capacity to move across the globe has induced a rapid and ongoing evolutionary shift in how genetic variation is distributed within and among local human populations. In particular, genetic differences between human populations are rapidly diminishing and individual heterozygosity is increasing, with beneficial health effects. Finally, even when cultural evolution eliminates selection on a trait, the trait can still evolve due to natural selection on other traits. Our traits are not isolated, independent units, but rather are integrated into a functional whole, so selection on one trait can cause evolution to occur on another trait, sometimes with mildly maladaptive consequences.

  15. Has human evolution stopped?

    Science.gov (United States)

    Templeton, Alan R

    2010-07-01

    It has been argued that human evolution has stopped because humans now adapt to their environment via cultural evolution and not biological evolution. However, all organisms adapt to their environment, and humans are no exception. Culture defines much of the human environment, so cultural evolution has actually led to adaptive evolution in humans. Examples are given to illustrate the rapid pace of adaptive evolution in response to cultural innovations. These adaptive responses have important implications for infectious diseases, Mendelian genetic diseases, and systemic diseases in current human populations. Moreover, evolution proceeds by mechanisms other than natural selection. The recent growth in human population size has greatly increased the reservoir of mutational variants in the human gene pool, thereby enhancing the potential for human evolution. The increase in human population size coupled with our increased capacity to move across the globe has induced a rapid and ongoing evolutionary shift in how genetic variation is distributed within and among local human populations. In particular, genetic differences between human populations are rapidly diminishing and individual heterozygosity is increasing, with beneficial health effects. Finally, even when cultural evolution eliminates selection on a trait, the trait can still evolve due to natural selection on other traits. Our traits are not isolated, independent units, but rather are integrated into a functional whole, so selection on one trait can cause evolution to occur on another trait, sometimes with mildly maladaptive consequences.

  16. The Molecular Basis of Evolution.

    Science.gov (United States)

    Wilson, Allan C.

    1985-01-01

    Discovery that mutations accumulate at steady rates over time in the genes of all lineages of plants and animals has led to new insights into evolution at the molecular and organismal levels. Discusses molecular evolution, examining deoxyribonuclei acid (DNA) sequences, morphological distances, and codon rate of change. (DH)

  17. Evolution of urological imaging.

    Science.gov (United States)

    Bueschen, Anton J; Lockhart, Mark E

    2011-02-01

    The evolution of urological imaging has had a major impact on the diagnosis and treatment of urological diseases since the discovery of the X-ray by Roentgen in 1895. Early developments included plain films of the abdomen, retrograde urographic techniques, development of contrast media, excretory urography, renal mass puncture, renal angiography, cystography and nuclear medicine procedures. These procedures led to the maturation of the specialties of diagnostic radiology and urology, and the development of the subspecialties of pediatric urology and urological radiology during the first seven decades of the 20th century. Subsequently, many imaging advances have occurred leading to changes in diagnosis and management of urological patients. Ultrasound and cross-sectional imaging technologies (computed tomography and magnetic resonance imaging) are increasingly applied in urological evaluation, treatment and surveillance. Current developments include dual energy computed tomography, positron emission tomography computed tomography, renal donor and renal transplant imaging, prostate magnetic resonance imaging, and microbubble contrast enhanced ultrasound. Imaging advances will continue. It is the responsibility of all physicians to assess the advantages of new developments while weighing those advantages against the additional radiation exposure and the costs associated with new procedures.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Tracy, Jenny; Jacobson, Arne; Mills, Evan

    2009-09-14

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

  20. Charge Management for Gravitational Wave Observatories using UV LEDs

    CERN Document Server

    Pollack, S E; Schlamminger, S; Hagedorn, C A; Gundlach, J H

    2009-01-01

    Accumulation of electrical charge on the end mirrors of gravitational wave observatories, such as the space-based LISA mission and ground-based LIGO detectors, can become a source of noise limiting the sensitivity of such detectors through electronic couplings to nearby surfaces. Torsion balances provide an ideal means for testing gravitational wave technologies due to their high sensitivity to small forces. Our torsion pendulum apparatus consists of a movable Au-coated Cu plate brought near a Au-coated Si plate pendulum suspended from a non-conducting quartz fiber. A UV LED located near the pendulum photoejects electrons from the surface, and a UV LED driven electron gun directs photoelectrons towards the pendulum surface. We have demonstrated both charging and discharging of the pendulum with equivalent charging rates of $\\sim

  1. Application of ultraviolet light-emitting diodes (UV-LEDs) for water disinfection: A review.

    Science.gov (United States)

    Song, Kai; Mohseni, Madjid; Taghipour, Fariborz

    2016-05-01

    Ultraviolet (UV) disinfection is an effective technology for the inactivation of pathogens in water and is of growing interest for industrial application. A new UV source - ultraviolet light-emitting diode (UV-LED) - has emerged in the past decade with a number of advantages compared to traditional UV mercury lamps. This promising alternative raises great interest in the research on application of UV-LEDs for water treatment. Studies on UV-LED water disinfection have increased during the past few years. This article presents a comprehensive review of recent studies on UV-LEDs with various wavelengths for the inactivation of different microorganisms. Many inconsistent and incomparable data were found from published studies, which underscores the importance of establishing a standard protocol for studying UV-LED inactivation of microorganisms. Different UV sensitivities to UV-LEDs and traditional UV lamps were observed in the literature for some microorganisms, which requires further investigation for a better understanding of microorganism response to UV-LEDs. The unique aspects of UV-LEDs improve inactivation effectiveness by applying LED special features, such as multiple wavelengths and pulsed illumination; however, more studies are needed to investigate the influencing factors and mechanisms. The special features of UV-LEDs offer the flexibility of novel reactor designs for a broad application of UV-LED reactors. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. High-power InGaN LEDs: present status and future prospects

    Science.gov (United States)

    Hahn, B.; Weimar, A.; Peter, M.; Baur, J.

    2008-02-01

    The ThinGaN ® technology of OSRAM Opto semiconductors enables high power LEDs with wall plug efficiencies of currently up to 50%, enabling efficacies of > 100lm/W for white and green LEDs. The good scalability of the technology enables devices which deliver high luminous flux. The future limitations regarding efficacy of white LED can be estimated to be 150lm/W for high color rendering. Besides efficiency long term stability and high temperature capability are requirements for market adoption

  3. Fundamentals of solid-state lighting LEDs, OLEDs, and their applications in illumination and displays

    CERN Document Server

    Khanna, Vinod Kumar

    2014-01-01

    History and Basics of LightingChronological History of LightingLearning Objectives How Early Man Looked at the ""Sun"" The Need for Artificial Light Sources First Steps in the Evolution of Artificial Lighting The First Solid-State Lighting Device The First Practical Electrical Lighting Device The Incandescent Filament Lamp Mercury and Sodium Vapor Lamps The Fluorescent Lamp The Compact Fluorescent Lamp Revolution in the World of Lighting: Advent of Light-Emitting Diodes Birth of the First LED and the Initial Stages of LED Development The Father of the LED: Holonyak Jr. The Post-1962 Developmen

  4. Solution of multi-element LED light sources development automation problem

    Science.gov (United States)

    Chertov, Aleksandr N.; Gorbunova, Elena V.; Korotaev, Valery V.; Peretyagin, Vladimir S.

    2014-09-01

    The intensive development of LED technologies resulted in the creation of multicomponent light sources in the form of controlled illumination devices based on usage of mentioned LED technologies. These light sources are used in different areas of production (for example, in the food industry for sorting products or in the textile industry for quality control, etc.). The use of LED lighting products in the devices used in specialized lighting, became possible due to wide range of colors of light, LED structures (which determines the direction of radiation, the spatial distribution and intensity of the radiation, electrical, heat, power and other characteristics), and of course, the possibility of obtaining any shade in a wide dynamic range of brightness values. LED-based lighting devices are notable for the diversity of parameters and characteristics, such as color radiation, location and number of emitters, etc. Although LED technologies have several advantages, however, they require more attention if you need to ensure a certain character of illumination distribution and/or distribution of the color picture at a predetermined distance (for example, at flat surface, work zone, area of analysis or observation). This paper presents software designed for the development of the multicomponent LED light sources. The possibility of obtaining the desired color and energy distribution at the zone of analysis by specifying the spatial parameters of the created multicomponent light source and using of real power, spectral and color parameters and characteristics of the LEDs is shown as well.

  5. Fractal properties of LED avalanche breakdown

    Directory of Open Access Journals (Sweden)

    Antonina S. Shashkina

    2016-12-01

    Full Text Available The conventional model of the processes occurring in the course of a p–n-junction's partial avalanche breakdown has been analyzed in this paper. Microplasma noise spectra of industrially produced LEDs were compared with those predicted by the model. It was established that the data obtained experimentally on reverse-biased LEDs could not be described in terms of this model. The degree to which the fractal properties were pronounced was shown to be variable by changing the reverse voltage. The discovered fractal properties of microplasma noise can serve as the basis for further studies which are bound to explain the breakdown characteristics of real LEDs and to correct the conventional model of p–n-junction's avalanche breakdown.

  6. Modeling the radiation pattern of LEDs.

    Science.gov (United States)

    Moreno, Ivan; Sun, Ching-Cherng

    2008-02-01

    Light-emitting diodes (LEDs) come in many varieties and with a wide range of radiation patterns. We propose a general, simple but accurate analytic representation for the radiation pattern of the light emitted from an LED. To accurately render both the angular intensity distribution and the irradiance spatial pattern, a simple phenomenological model takes into account the emitting surfaces (chip, chip array, or phosphor surface), and the light redirected by both the reflecting cup and the encapsulating lens. Mathematically, the pattern is described as the sum of a maximum of two or three Gaussian or cosine-power functions. The resulting equation is widely applicable for any kind of LED of practical interest. We accurately model a wide variety of radiation patterns from several world-class manufacturers.

  7. Optical communications. V - Light emitting diodes /LED/

    Science.gov (United States)

    Best, S. W.

    1980-10-01

    The process of assembling diode chips is discussed, along with their application in optical communications. Metal plating is performed with an evaporation technique using primarily AuGe on the back side and Al or AuZn on the front side. The assembling of LED-chips with metal casings is illustrated. The chip is mounted on a flat bottom plate and electrical contact is established by means of an alloying or adhesion procedure. A glass fiber can be attached to the diode and then fitted with a casing, or the diode can be assembled with a metal cap and a lense, or with an open cap that is sealed with a clear synthetic resin plastic. The typical emission spectra of an LED and a semiconductor laser are compared. Limitations in the operation of an LED in a photoconductor are examined, taking into account spectral line width and radiated power criteria.

  8. The mineral phase evolution behaviour in the production of glass-ceramics from municipal solid waste incineration fly ash by melting technology.

    Science.gov (United States)

    Luan, Jingde; Chai, Meiyun; Li, Rundong; Yao, Pengfei; Khan, Agha Saood

    2016-01-01

    High energy consumption was the major obstacle to the widespread application of melting technology in the treatment of municipal solid waste incineration fly ash. Aiming to lower the ash-melting temperature (AMT) for energy-saving, differential scanning calorimetry, X-ray diffraction and the scanning electron microscope were used to investigate the relations between AMT and the mineral evolution. The results indicated that the change of AMT was determined by the types and the contents of mineral crystals. The transition from refractory minerals to fluxing minerals was the key. The transition of the main crystalline phase from pseudowollastonite (Ca3(Si3O9)) to wollastonite (CaSiO3) played a significant role in AMT reduction. A quantum chemistry calculation was carried out to investigate the effect of crystal reaction activity on AMT. In the chemical reaction, the highest occupied molecular orbital and the lowest unoccupied molecular orbital played a more important role than any other orbits. Cations (Ca(2+), Mg(2+), Na(+), K(+)) were apt to enter into the crystal lattice of wollastonite and gehlenite mainly through Si (3), O (1), Si (6), O (10) and Al (2), O (10), and broke the covalent bonds of Si (3)-O (7), Al (1)-O (9) and Al (1)-O (15), respectively. This deconstruction behaviour provided convenient conditions for restructuring and promoted the formation of fluxing minerals. In melts, the excess SiO2 monomers which existed in the form of cristobalite and quartz caused AMT increase.

  9. LED module with high index lens

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-09-05

    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.

  10. Assessing the colour quality of LED sources

    DEFF Research Database (Denmark)

    Jost-Boissard, S.; Avouac, P.; Fontoynont, Marc

    2015-01-01

    sources and especially some LEDs. In this paper, several aspects of perceived colour quality are investigated using a side-by-side paired comparison method, and the following criteria: naturalness of fruits and vegetables, colourfulness of the Macbeth Color Checker chart, visual appreciation...... by the CIECAM02 Uniform Colour Space. Naturalness is better described by fidelity indices even if they did not give perfect predictions for all differences between LED light sources. Colourfulness is well described by gamut-based indices and attractiveness was found to correlate best with gamut-based indices...

  11. An LED solar simulator for student labs

    Science.gov (United States)

    González, Manuel I.

    2017-05-01

    Measuring voltage-current and voltage-power curves of a photovoltaic module is a nice experiment for high school and undergraduate students. In labs where real sunlight is not available this experiment requires a solar simulator. A prototype of a simulator using LED lamps has been manufactured and tested, and a comparison with classical halogen simulators has been performed. It is found that LED light offers lower levels of irradiance, but much better performance in terms of module output for a given irradiance.

  12. LED module with high index lens

    Energy Technology Data Exchange (ETDEWEB)

    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.

  13. Embedded systems for controlling LED matrix displays

    Science.gov (United States)

    Marghescu, Cristina; Drumea, Andrei

    2016-12-01

    LED matrix displays are a common presence in everyday life - they can be found in trains, buses, tramways, office information tables or outdoor media. The structure of the display unit is similar for all these devices, a matrix of light emitting diodes coupled between row and column lines, but there are many options for the display controller that switches these lines. Present paper analyzes different types of embedded systems that can control the LED matrix, based on single board computers, on microcontrollers with different peripheral devices or with programmable logic devices like field programmable gate arrays with implemented soft processor cores. Scalability, easiness of implementation and costs are analyzed for all proposed solutions.

  14. Design of the control system for full-color LED display based on MSP430 MCU

    Science.gov (United States)

    Li, Xue; Xu, Hui-juan; Qin, Ling-ling; Zheng, Long-jiang

    2013-08-01

    The LED display incorporate the micro electronic technique, computer technology and information processing as a whole, it becomes the most preponderant of a new generation of display media with the advantages of bright in color, high dynamic range, high brightness and long operating life, etc. The LED display has been widely used in the bank, securities trading, highway signs, airport and advertising, etc. According to the display color, the LED display screen is divided into monochrome screen, double color display and full color display. With the diversification of the LED display's color and the ceaseless rise of the display demands, the LED display's drive circuit and control technology also get the corresponding progress and development. The earliest monochrome screen just displaying Chinese characters, simple character or digital, so the requirements of the controller are relatively low. With the widely used of the double color LED display, the performance of its controller will also increase. In recent years, the full color LED display with three primary colors of red, green, blue and grayscale display effect has been highly attention with its rich and colorful display effect. Every true color pixel includes three son pixels of red, green, blue, using the space colour mixture to realize the multicolor. The dynamic scanning control system of LED full-color display is designed based on MSP430 microcontroller technology of the low power consumption. The gray control technology of this system used the new method of pulse width modulation (PWM) and 19 games show principle are combining. This method in meet 256 level grayscale display conditions, improves the efficiency of the LED light device, and enhances the administrative levels feels of the image. Drive circuit used 1/8 scanning constant current drive mode, and make full use of the single chip microcomputer I/O mouth resources to complete the control. The system supports text, pictures display of 256 grayscale

  15. Exploring Service-led Growth Trajectories for Analytical Equipment Providers

    DEFF Research Database (Denmark)

    Raja, Jawwad; Frandsen, Thomas; Mouritsen, Jan

    2016-01-01

    This paper examines the dilemmas encountered by advanced analytical equipment providers in developing service-led growth strategies to expand their business in pursuit of more attractive revenue models. It does so by adopting a case based research approach. The findings detail the capabilities...... and solutions-in different contexts, with a view to expanding markets and developing solution based business models, are discussed. It is argued that analytical equipment providers encounter dilemmas as managing these different trajectories implies different needs in terms of the technological sophistication...

  16. A high-performance stand-alone solar PV power system for LED lighting

    KAUST Repository

    Huang, B. J.

    2010-06-01

    The present study developed a high-performance solar PV power technology for the LED lighting of a solar home system. The nMPPO (near-Maximum-Power- Point- Operation) design is employed in system design to eliminate MPPT. A feedback control system using pulse width modulation (PWM) technique was developed for battery charging control which can increase the charging capacity by 78%. For high-efficiency lighting, the LED is directly driven by battery using a PWM discharge control to eliminate a DC/DC converter. Two solar-powered LED lighting systems (50W and 100W LED) were built. The long-term outdoor tests have shown that the loss of load probability for full-night lighting requirement is zero for 50W LED and 3.6% for 100W LED. © 2010 IEEE.

  17. LED Lighting in a Performing Arts Building

    Energy Technology Data Exchange (ETDEWEB)

    Miller, N. J.; Kaye, S. M. [Univ. of Florida, Gainesville, FL (United States); Coleman, P. M. [Univ. of Florida, Gainesville, FL (United States); Wilkerson, A. M.; Perrin, T. E.; Sullivan, G. P. [Efficiency Solutions, Inc., Richland, WA (United States)

    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.

  18. LED structure with enhanced mirror reflectivity

    Science.gov (United States)

    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.

  19. An LED Solar Simulator for Student Labs

    Science.gov (United States)

    González, Manuel I.

    2017-01-01

    Measuring voltage-current and voltage-power curves of a photovoltaic module is a nice experiment for high school and undergraduate students. In labs where real sunlight is not available this experiment requires a solar simulator. A prototype of a simulator using LED lamps has been manufactured and tested, and a comparison with classical halogen…

  20. Child-Led Enquiry in Primary Science

    Science.gov (United States)

    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)…

  1. Modeling of spectral characteristics of blue LEDs

    DEFF Research Database (Denmark)

    Thorseth, Anders

    2010-01-01

    are expected to vary with current and junction temperature. Commercial high power blue LEDs were measured with respect to spectral distribution and chromaticity and the result was compared with the model predictions. We have found that the models predict significantly different results with respect...

  2. Preliminary investigations of piezoelectric based LED luminary

    DEFF Research Database (Denmark)

    Nielsen, Dennis; Andersen, Michael A. E.; Meyer, Kaspar Sinding

    2011-01-01

    This paper presents a preliminary study of PT (Piezoelectric Transformer) based SMPS’s (Switch Mode Power Supplies) for LED luminary. The unique properties of PTs (efficiency, power density and EMI) make them highly suitable for this application. Power stage topologies, rectifiers circuits, modul...

  3. Perceived Learning Effectiveness of a Course Facebook Page: Teacher-Led versus Student-Led Approach

    Science.gov (United States)

    Tugrul, Tugba Orten

    2017-01-01

    This research aims to compare the perceived effectiveness of teacher-led and student-led content management approaches embraced in a course Facebook page designed to enhance traditional classroom learning. Eighty-five undergraduate marketing course students voluntarily completed a questionnaire composed of two parts; a depiction of a course…

  4. EDITORIAL: Micro-pixellated LEDs for science and instrumentation

    Science.gov (United States)

    Dawson, Martin D.; Neil, Mark A. A.

    2008-05-01

    This Cluster Issue of Journal of Physics D: Applied Physics highlights micro-pixellated gallium nitride light-emitting diodes or `micro-LEDs', an emerging technology offering considerable attractions for a broad range of scientific and instrumentation applications. It showcases the results of a Research Councils UK (RCUK) Basic Technology Research programme (http://bt-onethousand.photonics.ac.uk), running from 2004-2008, which has drawn together a multi-disciplinary and multi-institutional research partnership to develop these devices and explore their potential. Images of LEDs Examples of GaN micro-pixel LEDs in operation. Images supplied courtesy of the Guest Editors. The partnership, of physicists, engineers and chemists drawn from the University of Strathclyde, Heriot-Watt University, the University of Sheffield and Imperial College London, has sought to move beyond the established mass-market uses of gallium nitride LEDs in illumination and lighting. Instead, it focuses on specialised solid-state micro-projection devices the size of a match-head, containing up to several thousand individually-addressable micro-pixel elements emitting light in the ultraviolet or visible regions of the spectrum. Such sources are pattern-programmable under computer control and can project into materials fixed or high-frame rate optical images or spatially-controllable patterns of nanosecond excitation pulses. These materials can be as diverse as biological cells and tissues, biopolymers, photoresists and organic semiconductors, leading to new developments in optical microscopy, bio-sensing and chemical sensing, mask-free lithography and direct writing, and organic electronics. Particular areas of interest are multi-modal microscopy, integrated forms of organic semiconductor lasers, lab-on-a-chip, GaN/Si optoelectronics and hybrid inorganic/organic semiconductor structures. This Cluster Issue contains four invited papers and ten contributed papers. The invited papers serve to set

  5. Commerical Transition to LEDs: A Pathway to High-Value Products

    Science.gov (United States)

    Stutte, Gary W.

    2015-01-01

    The use of light-emitting diodes (LEDs) to support plant growth is a radical departure from use of gas-discharge lamps, which were developed in mid-19th and widely adopted by the industry during the 20th century. Initial investigation by the National Aeronautics and Space Administration (NASA) in the late 1980s on the use of LEDs to grow plant in space is resulting in an industry-wide transition from gas discharge to solid-state lighting systems. This global transformation is given urgency by national policies to reduce energy consumption and being facilitated by ready access to information on LEDs. The combination of research, government policy, and information technology has resulted in an exponential increase in research into the use and application of LED technology in horticulture. Commercial horticulture has identified the opportunities provided by LEDs to optimize light spectra to promote growth, regulate morphology, increase nutrient content, and reduce operating costs. LED-light technology is enabling the development of innovative lighting systems, and is being incorporated into large-scale plant factories for the production of edible, ornamental, and medicinal plants. An overview of prevalence of readily accessible information on LEDs and implications for future adoption in horticulture is discussed.

  6. The origins of the Acheulean: past and present perspectives on a major transition in human evolution.

    Science.gov (United States)

    de la Torre, Ignacio

    2016-07-01

    The emergence of the Acheulean from the earlier Oldowan constitutes a major transition in human evolution, the theme of this special issue. This paper discusses the evidence for the origins of the Acheulean, a cornerstone in the history of human technology, from two perspectives; firstly, a review of the history of investigations on Acheulean research is presented. This approach introduces the evolution of theories throughout the development of the discipline, and reviews the way in which cumulative knowledge led to the prevalent explanatory framework for the emergence of the Acheulean. The second part presents the current state of the art in Acheulean origins research, and reviews the hard evidence for the appearance of this technology in Africa around 1.7 Ma, and its significance for the evolutionary history of Homo erectusThis article is part of the themed issue 'Major transitions in human evolution'.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-10-14

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

  8. The establishment of reliability model for LED lamps

    Science.gov (United States)

    Jian, Hao; Lei, Jing; Yao, Wang; Qun, Gao; Hongliang, Ke; Xiaoxun, Wang; Yanchao, Zhang; Qiang, Sun; Zhijun, Xu

    2016-07-01

    In order to verify which of the distributions and established methods of reliability model are more suitable for the analysis of the accelerated aging of LED lamp, three established methods (approximate method, analytical method and two-stage method) of reliability model are used to analyze the experimental data under the condition of the Weibull distribution and Lognormal distribution, in this paper. Ten LED lamps are selected for the accelerated aging experiment and the luminous fluxes are measured at an accelerated aging temperature. AIC information criterion is adopted in the evaluation of the models. The results show that the accuracies of the analytical method and the two-stage method are higher than that of the approximation method, with the widths of confidence intervals of unknown parameters of the reliability model being the smallest for the two-stage method. In a comparison between the two types of distributions, the accuracies are nearly identical. Project supported by the National High Technology Research and Development Program of China (Nos. 2015AA03A101, 2013AA03A116), the Cuican Project of Chinese Academy of Sciences (No. KZCC-EW-102), and the Jilin Province Science and Technology Development Plan Item (No. 20130206018GX).

  9. Notes on LED Installations in Street Illumination

    Directory of Open Access Journals (Sweden)

    Elisabeta Spunei

    2014-09-01

    Full Text Available The paper presents a study made on choosing LED street lighting installations, such that the quality requirements for exterior artificial lighting are fulfilled. We analyze two types of LED street lighting installations from a technical point of view, together with lighting level and brightness values obtained during the measurements. Following on the field measurements, the lighting quality parameters are calculated, and, for the lighting installation with the best performance, optimal mounting suggestions are made. The optimal quality parameters are calculated by simulations using the Dialux software. The same software and the same light sources we also compute an optimal street lighting by determining the size of the installation that provides the best lighting parameter values.

  10. LED i Københavns Kommunes gadebelysning

    DEFF Research Database (Denmark)

    Bülow, Katja

    2016-01-01

    Artiklen i denne udgivelse formidler resultatet af en undersøgelse, hvor de visuelle forhold i Københavns Kommunes gader undersøges som resultat af gadens belysning. Der lægges vægt på metoden bag undersøgelsen og på hvordan indførelsen af LED forandrer belysningen i gaderne.......Artiklen i denne udgivelse formidler resultatet af en undersøgelse, hvor de visuelle forhold i Københavns Kommunes gader undersøges som resultat af gadens belysning. Der lægges vægt på metoden bag undersøgelsen og på hvordan indførelsen af LED forandrer belysningen i gaderne....

  11. Imprint lithography advances in LED manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Hershey, Robert; Doyle, Gary; Jones, Chris; LaBrake, Dwayne; Miller, Mike [Molecular Imprints Inc., 1807 West Braker Lane, Building C-11, Austin, TX 78758 (United States)

    2007-07-01

    Imprint lithography is a promising cost effect alternative to e-beam and optical lithography for producing photonic crystals and other nano-scale light extraction and beam directing elements for LEDs; however, there are several challenges that must be overcome before imprint lithography can be applied to typical LED substrates. This paper reviews progress made at Molecular Imprints Inc. (MII) in imprinting representative 3{sup ''} GaN on Sapphire substrates including methods for dealing with substrate non-flatness, multi-die imprint, and imprinting on warped and bowed substrates. The results of imprinting over typical GaN on Sapphire topography and common defects such as fall-on particles and EPI defects is presented along with results on GaN wafers optimized for imprint lithography. Whole wafer thin template replication techniques are also discussed. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  12. EVALUATING THE CULTURE-LED REGENERATION

    Directory of Open Access Journals (Sweden)

    D'Angelo Francesca

    2010-12-01

    Full Text Available The aim of the paper is to propose a new approach to urban planning, evaluating the culture-led regeneration processes. In the last few years, the cultural turn in urban planning played a central role in the urban studies. In this way we try to elaborate a more robust perspective interpreting the complex phenomenology emerging from the culture-led regeneration processes. Within the concept of complexity we discuss about the metabolic process that are the processes necessary to transform energy, material and information in goods and service functional to the complex urban system life. The approach that will be employed is the MuSIASEM that is based on several novel concept and an innovative methods never applied in this research field.

  13. Fluorescent protein integrated white LEDs for displays

    Science.gov (United States)

    Press, Daniel Aaron; Melikov, Rustamzhon; Conkar, Deniz; Nur Firat-Karalar, Elif; Nizamoglu, Sedat

    2016-11-01

    The usage time of displays (e.g., TVs, mobile phones, etc) is in general shorter than their functional life time, which worsens the electronic waste (e-waste) problem around the world. The integration of biomaterials into electronics can help to reduce the e-waste problem. In this study, we demonstrate fluorescent protein integrated white LEDs to use as a backlight source for liquid crystal (LC) displays for the first time. We express and purify enhanced green fluorescent protein (eGFP) and monomeric Cherry protein (mCherry), and afterward we integrate these proteins as a wavelength-converter on a blue LED chip. The protein-integrated backlight exhibits a high luminous efficacy of 248 lm/Wopt and the area of the gamut covers 80% of the NTSC color gamut. The resultant colors and objects in the image on the display can be well observed and distinguished. Therefore, fluorescent proteins show promise for display applications.

  14. Cooling of led module by various radiators

    Directory of Open Access Journals (Sweden)

    Naumova A. M.

    2015-12-01

    Full Text Available Given article presents the results of an experimental comparison of three radiators which are: pressed radiator made of aluminum plate (basic variant, radiator made of copper wire, and copper/water pulsating heat pipe. The radiators are intended to take off heat from the LED module with the power capacity of 10,55 W. It is established that under natural convection all three radiators can keep temperature level of the circuit board module less than 64 C that lies within the operating range. In comparison with basic variant the use of the copper wire radiator allows lowering of the temperature in the LED module center on 3.9 C, and the same value for the pulsating heat pipe is 7.1 C.

  15. Uniform LED illuminator for miniature displays

    Science.gov (United States)

    Medvedev, Vladimir; Pelka, David G.; Parkyn, William A.

    1998-10-01

    The Total Internally Reflecting (TIR) lens is a faceted structure composed of prismatic elements that collect a source's light over a much larger angular range than a conventional Fresnel lens. It has been successfully applied to the efficient collimation of light from incandescent and fluorescent lamps, and from light-emitting diodes (LEDs). A novel LED-powered collimating backlight is presented here, for uniformly illuminating 0.25'-diagonal miniature liquid- crystal displays, which are a burgeoning market for pagers, cellular phones, digital cameras, camcorders, and virtual- reality displays. The backlight lens consists of a central dual-asphere refracting section and an outer TIR section, properly curved with a curved exit face.

  16. Evolution of Seigniorage in a Period of Profound Economic Transformations

    Directory of Open Access Journals (Sweden)

    Manuel Bernal Garzón

    2015-01-01

    Full Text Available This paper presents an analysis of seigniorage in Colombia in the period 1984-2013, which is characterized by profound technological advances and a number of political, social and cultural events worldwide affecting both global and national economies. These changes, together with modifications in the principles of economic thinking in policy managers, under the pressure of multilateral lending agencies and due to new realities, have led to a series of structural reforms that generated institutional changes both in exchange rate and financial regimes affecting monetary policy, and, therefore, the behavior of primary and secondary seigniorage. Finally, the relationship between these changes and the evolution of seigniorage is addressed.

  17. Nurse-led management of contraceptive services.

    Science.gov (United States)

    Wilson, Emma

    2014-07-01

    This article discusses the role of the practice nurse (PN) in the provision of health assessment for contraceptive choices. PNs who have an extended role as an independent nurse prescriber must demonstrate the principles of safe prescribing practice, with appropriate and informed assessment of the patient's needs and risk within the limited time of a general practice appointment. With continued professional development, PNs are well placed to provide comprehensive, independent nurse-led contraceptive services.

  18. Study and Design of LED Lighting Systems

    Directory of Open Access Journals (Sweden)

    Li Cheng

    2013-06-01

    Full Text Available In this study, the optical characteristics, thermal characteristics, electrical characteristics of the LED device are studied. After analysis of the significance of the optical model, we establish the model of the LED light source using optical simulation software to analyze the impact of modeling four factors and law, based on ray tracing model intensity distribution with the manufacturers. On this basis, we expand the LED secondary optical design, namely, increasing of LDE method to the light level. After comparing different forms of non-imaging optical components, combined with the actual situation, the final choice is the system composed of rotating parabolic reflector with LDE. Besides, the reflected changing the relative position of the body and LDE space lead to the normal light intensity of the entire system appearing two peaks, but their causes are different. In addition, the method of combining theoretical analysis and computer simulations to study the distribution of LDE array illumination is utilized. Formula on the illumination distribution in the LDB array to a plane parallel thereto is deduced, which is verified by computer simulation and agrees well with it. A quantitative study of the factors affecting the road surface illuminance distribution is made on the basis of previous study, combined with the actual road lighting works. These factors are: LDE array form, the number of LED, spacing between LDE, LDE interval between the street lamps. The derived entire road illumination distribution formula and the corresponding curve gives a basic method for the analysis of such practical problems related outcomes for the LDE illumination optical system design and research basis.

  19. Curing efficiency of modern LED units.

    Science.gov (United States)

    Rencz, Adam; Hickel, Reinhard; Ilie, Nicoleta

    2012-02-01

    Recent reports claim that modern light-emitting diode (LED) curing units improve curing efficiency by increasing the units' irradiance. In this context also, short polymerisation times up to 5 s are proposed. The aim of this study was to examine whether there are differences in the curing efficiency of modern LED curing units by assessing their effect on two different composite materials and by varying the irradiation time. A nano- and a micro-hybrid resin-based composite (RBC) were polymerised for 5, 10 and 20 s with three commercial and a Prototype LED unit (Elipar™ S10). Cylindrical specimens (6 mm in depth, 4 mm in diameter) were prepared in three increments, each 2-mm thick, and were consecutively cured. Degree of cure was measured for 20 min in real time at the bottom of the samples, starting with the photoinitiation. The micro-mechanical properties (modulus of elasticity, E and Vickers hardness, HV) were measured as a function of depth, in 100-μm steps, on the above described samples stored in distilled water for 24 h at 37°C. Data were analysed with multivariate ANOVA followed by Tukey's test, t test and partial eta-squared statistics. In descending order of the strength of their effect, the type of RBC, depth, polymerisation time and curing unit were significant factors affecting the micro-mechanical parameters (p surface, a minimum of 20 s of irradiation is necessary for an adequate polymerisation 2 mm beyond the surface.

  20. High brightness near-ultraviolet resonant LEDs

    Energy Technology Data Exchange (ETDEWEB)

    Corbett, B.; Roycroft, B.; Maaskant, P.; Akhter, M. [Tyndall National Institute, Lee Maltings, Prospect Row, Cork (Ireland); Zhu, D.; McAleese, C.; Kappers, M.J.; Humphreys, C.J. [Department of Materials Science and Metallurgy, University of Cambridge, Cambridge, CB2 3QZ (United Kingdom)

    2008-07-01

    Planar near-ultraviolet 385 nm emitting resonant LEDs containing three quantum wells have been investigated as a function of the separation between the wells and a reflective and injecting metal mirror. The output power and far-field extracted through the substrate of the LEDs depend on the precise positions of the wells with each well having a significant individual influence on these properties. A doubling of the output power is obtained when the wells are located around the antinode position of the standing wave while narrower far-fields are obtained with other placement of the wells. A power of 0.4 mW into a numerical aperture of 0.5 is obtained for a current of 30 mA into a 50 {mu}m diameter contact. Calibration of the growth rate along with accurate knowledge of the material properties of the semiconductor and metal mirrors is required for controlled and enhanced emission from planar UV LEDs. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  1. Export-led Growth Hypothesis: Turkey Application

    Directory of Open Access Journals (Sweden)

    İsmail KÜÇÜKAKSOY

    2015-12-01

    Full Text Available This paper aims to investigate validity of “Export-led Growth Hypothesis” for Turkey using quarterly data in period from 2003:Q1 to 2015:Q1. Hypothesis argues that there is causality relationship from real export to real Gross Domestic Product (GDP. Johansen cointegration test, Gregory-Hansen cointegration test, Toda-Yamamoto causality test, Fully Modified Ordinary Least Squares (FMOLS, Canonical cointegrating regression (CCR and Dynamic ordinary least squares (DOLS methods were used in this study. Findings can be summarized as follows: a According to Johansen cointegration test there is no relationship among variables in the long-run whereas Gregory-Hansen cointegration test has determined relationship in the long-run; b According to Toda-Yamamoto causality test there is bidirectional causality between real export and real GDP. This finding proves the validity of “Export-led Growth Hypothesis” for Turkey; c According to FMOLS, CCR, DOLS methods a 1% increase in the real export increases the real GDP by 1.5195%, 1.5552%, 1.3171% respectively in the long-run. These methods prove the validity of “Export-led Growth Hypothesis” for Turkey.

  2. SIM Configuration Evolution

    Science.gov (United States)

    Aaron, Kim M.

    2000-01-01

    , picometer measurement of wavefront, and others. In order to meet these goals, a significant amount of technological development is required. Although there has been a program operating for about a decade developing technologies specifically to address the challenges of space-based interferometry, there still remains a tremendous effort to achieve the incredible accuracy required of SIM. The projected viability of some of these areas has influenced design choices during the evolution of the many configurations that have been developed. For instance, the perceived complexity of the IR laser metrology system used to measure and control the positions of key optical elements was the strongest discriminator between the two architectures, and led to a decision to select SOS rather than Classic in early 1998. More recently, an appreciation of the sensitivity to beam-walk within the SOS architecture is forcing a reconsideration of that decision. At the time of submission of this abstract, there is some hope that a full-aperture metrology system may alleviate this issue. In addition to describing the current configuration of SIM, the influence of a few selected areas on the evolution of the configuration will be discussed.

  3. Birth and evolution of visionics

    Science.gov (United States)

    Wiseman, Robert S.

    1992-09-01

    The success of the U.S. Army's Night Vision Program at Fort Belvoir, VA was significantly influenced by the evolution and timely culmination of Visionics technology which was initiated by Mr. John Johnson. In the late 1950's, Visionics technology started with concern for Near Infrared (NIR) and Image Intensifier (II) Night Vision developments. It resulted in the Johnson Criteria which coupled system physical characteristics to visual performance by using resolution of line pairs across the minimum dimension of a target. This led to development of image evaluation procedures and standardized laboratory testing. Later the Visionics team addressed the Far Infrared (FIR) system performance and developed a series of FLIR Performance Models. The Visionic's Static Performance Model computer code was accepted and proliferated widely by the mid-70's. Visionics moved from static viewing to address the problems of search effectiveness. Then came more work on target signatures and the consideration of the effects of fog, rain, snow, artillery barrages, and realistic battlefield conditions on system performance in order to assure the utility of fielded equipments for all theaters of interest. The general use of the various Visionics models and methodology throughout Government and Industry is recognition of the contributions made by Mr. John Johnson and his Visionics staff.

  4. Benefits and challenges of controlling a LED AFS (Adaptive Front-lighting System) using fuzzy logic

    OpenAIRE

    2011-01-01

    Texto completo: acesso restrito. p.579−588 The vehicular illumination system has undergone considerable technological advances in recent decades such as the use of a Light Emitting Diode (LED) Adaptive Front-lighting System (AFS), which represents an industry breakthrough in lighting technology and is rapidly becoming one of the most important innovative technologies around the world in the lighting community. This paper presents AFS control alternatives using fuzzy logic (types 1...

  5. Light out-coupling from LEDs by means of metal nanoparticles; Lichtauskopplung aus LEDs mittels Metallnanoteilchen

    Energy Technology Data Exchange (ETDEWEB)

    Goehler, Tino

    2010-12-17

    The external quantum efficiency of light-emitting diodes (LEDs) based on Al- GaAs/InGaAlP is limited by total internal reflection because of the high refractive index (typically between 3 and 4) of the semiconductor. Metal nanoparticles (MNP) deposited on the surface of the LED can be used as dipole scatterers in order to enhance the emission of the LED. In this thesis, first, single gold nanoparticles of various sizes deposited on such an LED were investigated. A clear enhancement is detected as long as the dipole plasmon resonance of the particle is at a shorter wavelength than the LED emission. If the plasmon resonance coincides with the LED emission or is at a larger wavelength, the enhancement turns into suppression. Numerical simulations indicate that this latter effect is mainly caused by the particle quadrupole resonance producing extra absorption. Arrays of MNPs can be produced by a special mask technique called ''Fischer pattern nanolithography'' and manipulated in shape and size by additional steps. Originally, the MNPs produced by this technique are triangular in shape and turn out to suppress the LED emission. After transformation of the particles to spheres, a clear enhancement was detected. Light that would otherwise remain trapped inside the substrate is coupled out by resonant plasmonic scattering. Investigations on analogous structures on a transparent high-index material (GaP) indicate a stronger coupling between the particles than expected on the basis of literature data. (orig.)

  6. Use of DNA technology in forensic dentistry.

    Science.gov (United States)

    da Silva, Ricardo Henrique Alves; Sales-Peres, Arsenio; de Oliveira, Rogério Nogueira; de Oliveira, Fernando Toledo; Sales-Peres, Sílvia Helena de Carvalho

    2007-06-01

    The established importance of Forensic Dentistry for human identification, mainly when there is little remaining material to perform such identification (e.g., in fires, explosions, decomposing bodies or skeletonized bodies), has led dentists working with forensic investigation to become more familiar with the new molecular biology techniques. The currently available DNA tests have high reliability and are accepted as legal proofs in courts. This article presents a literature review referring to the main studies on Forensic Dentistry that involve the use of DNA for human identification, and makes an overview of the evolution of this technology in the last years, highlighting the importance of molecular biology in forensic sciences.

  7. Perceived learning effectiveness of a course Facebook page: teacher-led versus student-led approach

    Directory of Open Access Journals (Sweden)

    Tugba Orten Tugrul

    2017-01-01

    Full Text Available This research aims to compare the perceived effectiveness of teacher -led and student-led content management approaches embraced in a course Facebook page designed to enhance traditional classroom learning. Eighty-five undergraduate marketing course students voluntarily completed a questionnaire composed of two parts; a depiction of a course Facebook page where both teacher and students can share instructional contents, and questions about perceived learning effectiveness. The findings indicate that students have more favorable evaluations of a student-led approach in sharing instructional contents on a course Facebook Page than a teacher-led approach. Additionally, it is shown that instructional contents posted by both teacher and students enhance the overall learning effectiveness of a course Facebook page incorporated into a traditional classroom teaching.

  8. Phosphor-in-glass for high-powered remote-type white AC-LED.

    Science.gov (United States)

    Lin, Hang; Wang, Bo; Xu, Ju; Zhang, Rui; Chen, Hui; Yu, Yunlong; Wang, Yuansheng

    2014-12-10

    The high-powered alternating current (AC) light-emitting diode (LED) (AC-LED), featuring low cost, high energy utilization efficiency, and long service life, will become a new economic growth point in the field of semiconductor lighting. However, flicker of AC-LED in the AC cycles is not healthy for human eyes, and therefore need to be restrained. Herein we report an innovation of persistent "phosphor-in-glass" (PiG) for the remote-type AC-LED, whose afterglow can be efficiently activated by the blue light. It is experimentally demonstrated that the afterglow decay of PiG in the microsecond range can partly compensate the AC time gap. Moreover, the substitution of inorganic glass for organic resins or silicones as the encapsulants would bring out several technological benefits to AC-LED, such as good heat-dissipation, low glare, and excellent physical/chemical stability.

  9. Single chip super broadband InGaN/GaN LED enabled by nanostructured substrate.

    Science.gov (United States)

    Yin, Stuart Shizhuo; Wang, Chao; Zhu, Wenbin; Yao, Jimmy; Zou, Jun; Lin, Xiaoyan; Luo, Claire

    2014-08-25

    A new type of LED, single chip super broadband InGaN/GaN LED is presented in this paper. The LED is composed of an InGaN/GaN quantum well layer deposited on the nanostructured sapphire substrate, inscribed by femtosecond laser ablation. The super broadband emission is enabled due to the large variation of indium composition in a small local area so that different wavelengths can be emitted over a small area and the summation of these different emission wavelengths forms super broadband emission, which covers the entire visible spectral range. The result of this paper represents a major technological advance in white light LED lighting because it enables single chip white LED lighting without the need of phosphor down converter that can significantly improve the efficiency without the Stokes loss and reduce the cost.

  10. LED to LED communication with WDM concept for flash light of Mobile phones

    Directory of Open Access Journals (Sweden)

    Devendra J Varanva

    2013-08-01

    Full Text Available After observing recent developments in Free Space Optical Communication especially Visible Light Communication, It is clear that LED is main component as a source. LED being solid state device makes endless list of possibilities. But here we will get through its ability to sense light as well, and use of Wavelength Division Multiplexing (WDM in mobile flash is also suggested, this opens door to many applications.

  11. DSP Technology and Methods for OCT

    Science.gov (United States)

    Ali, Murtaza; Ahmad, Adeel; Boppart, Stephen A.

    Medical imaging devices are continually changing and evolving. In recent years, these devices have been evolving towards portable and handheld point-of-care systems. Innovations in the semiconductor technologies have been a major driving factor for such evolution. Today, optical coherence tomography (OCT) systems are mostly cart-based or desktop systems. Portable and hand-held OCT systems will open up new opportunities for their use. Recent advances in optics and scanning techniques have led to miniaturization of the optics used to acquire the raw data and at the same time, allow very high data acquisition rate. The signal processing chain to convert this raw acquired data into useful structural images is computationally intensive. The semiconductor industry, however, has a class of embedded processor technologies, known as digital signal processors (DSP), designed to take on such computations with very low power and size. DSP technology is a crucial enabler to create low power, low cost, handheld and portable OCT systems.

  12. LED Context Lighting System in Residential Areas

    Directory of Open Access Journals (Sweden)

    Sook-Youn Kwon

    2014-01-01

    Full Text Available 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.

  13. LED context lighting system in residential areas.

    Science.gov (United States)

    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.

  14. LED and OLED Devices Compare in Lighting Application and Industry Development%照明应用中LED和OLED的比较及产业发展分析

    Institute of Scientific and Technical Information of China (English)

    张天翼; 顾磊

    2013-01-01

    The fourth generation lighting-semiconductor lighting ( light emitting diode , LED) and the fifth generation lighting-organic lighting ( organic light emitting diode , OLED ) technologies have both entered the era of industrialization and commercial production .This paper reviewed the history of LED and OLED development , especially the evolution of their application in lighting industries .The authors conducted computer simulation analysis on OLED lighting panels from a leading manufacturing company and compared the resulted lighting effects with that of a sample LED lamp .On the other hand , cost to produce OLED panels as well as the LED lamp was also discussed .In the end of this paper , based on these cost and effectiveness analysis and the current industry development status , the authors provided perspectives on outlook of the LED and OLED lighting industry and gave future development proposals aiming to benefit all the related parties in the advanced lighting industry .%本文回顾LED和OLED的发展史,尤其是两者在照明领域的应用进程。通过计算机模拟的方法选取国际知名厂商生产的OLED照明面板与LED灯具进行照明效果比较,同时对两者的成本进行了讨论。在成本分析的基础上,对LED和OLED照明市场发展进行了预测,并结合产业发展现状给出发展建议。

  15. Evolution of Ore Deposits and Technology Transfer Project: Isotope and Chemical Methods in Support of the U.S. Geological Survey Science Strategy, 2003-2008

    Science.gov (United States)

    Rye, Robert O.; Johnson, Craig A.; Landis, Gary P.; Hofstra, Albert H.; Emsbo, Poul; Stricker, Craig A.; Hunt, Andrew G.; Rusk, Brian G.

    2010-01-01

    Principal functions of the U.S. Geological Survey (USGS) Mineral Resources Program are providing assessments of the location, quantity, and quality of undiscovered mineral deposits, and predicting the environmental impacts of exploration and mine development. The mineral and environmental assessments of domestic deposits are used by planners and decisionmakers to improve the stewardship of public lands and public resources. Assessments of undiscovered mineral deposits on a global scale reveal the potential availability of minerals to the United States and other countries that manufacture goods imported to the United States. These resources are of fundamental relevance to national and international economic and security policy in our globalized world economy. Performing mineral and environmental assessments requires that predictions be made of the likelihood of undiscovered deposits. The predictions are based on geologic and geoenvironmental models that are constructed for the diverse types of mineral deposits from detailed descriptions of actual deposits and detailed understanding of the processes that formed them. Over the past three decades the understanding of ore-forming processes has benefited greatly from the integration of laboratory-based geochemical tools with field observations and other data sources. Under the aegis of the Evolution of Ore Deposits and Technology Transfer Project (referred to hereinafter as the Project), a 5-year effort that terminated in 2008, the Mineral Resources Program provided state-of-the-art analytical capabilities to support applications of several related geochemical tools to ore-deposit-related studies. The analytical capabilities and scientific approaches developed within the Project have wide applicability within Earth-system science. For this reason the Project Laboratories represent a valuable catalyst for interdisciplinary collaborations of the type that should be formed in the coming years for the United States to meet

  16. 基于核心-辅助技术匹配的二次创新及其演化路径研究%Secondary Innovation and Evolution Path based on the Fitness between Core and Complementary Technologies

    Institute of Scientific and Technical Information of China (English)

    吴晓波; 窦伟; 高钰; 黄芳俪

    2011-01-01

    complementary technology. We conduct a longitudinal case study based on latercomer's learning and catch-up theories to derive an evolutionary learning path. The path improves the understanding of secondary innovation for latecomers.The first part of this article reviews the innovation of latercomers, including catch-up, absorption learning and complementary technologies. The literature review leads to a learning process framework that considers the evolution process of core and complementary technologies from longitudinal and evolutional perspectives. A longitudinal case study is pertinent because it enables us to compare characteristics of core and complementary technology learning processes. The second part of this paper uses category coding tecniques to conduct a case study of ZTE with respect to its core and complementary technological learning processes. Technological standard, system architecture and main/foundamental functional components of one type equipment are coded as core technologies. The common components and applied design are coded as complementary technologies. The third part proposes three innovation phases after conducting a longitudinal analysis. In the secondary innovation phase, latecomers source or imitate mature core technology, and exploit local complemetnary technology. In the post secondary innovation phase, latecomers exploit and track core technology, as well as explore complementary technology with value-added innovations. In the first innovation phase, latecomers explore core technology and chose generic ( exploitation) or specialized ( exploration) complementary technology according to the leading position of technology. The last part summarizes two theoretical proposition. First, latecomers' innovation in developing countries follow an evolution process from core technology imitation, exploitation to exploration. Strategy execution of acquiring complementary technology will change from exploitation to exploration faster than that of acquiring

  17. Lithic technology and behavioral variability during the Middle Stone Age of southern Africa: Implications for the evolution and dispersal of early modern humans

    OpenAIRE

    Will, Manuel

    2016-01-01

    The Middle Stone Age (MSA) of Africa encompasses the archaeological background for the origin, early evolution and global dispersal of Homo sapiens. This dissertation project used behavioral information attained from the analysis of MSA stone artifacts, in concert with additional archaeological data and new theoretical concepts, to assess research questions pertaining to key issues in current MSA archaeology and human evolution: What is the nature of coastal adaptations during the MSA and how...

  18. An Overview of LEDs' Effects on the Production of Bioactive Compounds and Crop Quality.

    Science.gov (United States)

    Hasan, Md Mohidul; Bashir, Tufail; Ghosh, Ritesh; Lee, Sun Keun; Bae, Hanhong

    2017-08-27

    Light-emitting diodes (LEDs) are characterized by their narrow-spectrum, non-thermal photon emission, greater longevity, and energy-saving characteristics, which are better than traditional light sources. LEDs thus hold the potential to revolutionize horticulture lighting technology for crop production, protection, and preservation. Exposure to different LED wavelengths can induce the synthesis of bioactive compounds and antioxidants, which in turn can improve the nutritional quality of horticultural crops. Similarly, LEDs increase the nutrient contents, reduce microbial contamination, and alter the ripening of postharvest fruits and vegetables. LED-treated agronomic products can be beneficial for human health due to their good nutrient value and high antioxidant properties. Besides that, the non-thermal properties of LEDs make them easy to use in closed-canopy or within-canopy lighting systems. Such configurations minimize electricity consumption by maintaining optimal incident photon fluxes. Interestingly, red, blue, and green LEDs can induce systemic acquired resistance in various plant species against fungal pathogens. Hence, when seasonal clouds restrict sunlight, LEDs can provide a controllable, alternative source of selected single or mixed wavelength photon source in greenhouse conditions.

  19. The avalanche-mode superjunction LED

    NARCIS (Netherlands)

    Dutta, Satadal; Steeneken, Peter G.; Agarwal, Vishal Vishal; Schmitz, Jurriaan; Annema, Anne J.; Hueting, Raymond Josephus Engelbart

    2017-01-01

    Avalanche-mode light-emitting diodes (AMLEDs) in silicon (Si) are potential light sources to enable monolithic optical links in standard CMOS technology, due to the large overlap of their electroluminescent (EL) spectra with the responsivity of Si photodiodes. These EL spectra depend on the reverse

  20. Application of Remote FPGA Dynamic Reconfiguration System in LED Lighting

    Institute of Scientific and Technical Information of China (English)

    LI Wei; WANG Wei; NIU Ping-juan; ZHANG li-ping

    2009-01-01

    The dynamic reconfiguration technique based on field-programmable gate array (FPGA) can improve the resource utilization.Discussed are the dynamic reconfiguration principles and methods.Proposed is a remote dynamic reconfiguration scheme using Xilinx Virtex-II FPGA and SMCS Ethernet Physical layer transceiver(PHY).The hardware of the system is designed with Xilinx Virtex-II XC2V30P FPGA that embedds MicroBlaze and MAC IP core,and its network communication software based on transmission control protocol/Internet protocol (TCP/IP) protocol is programmed by loading LwlP to MicroBlaze. The experimental results indicate that the remote FPGA dynamic reconfiguration system(RFDRS) can switch freely in the eight lighting modes of light emitting diodes (LED),and that,using dynamic reconfiguration technology,FPGA resource utilization can be reduced remarkably,which is advantageous in the system upgrade and software update.

  1. LED Lightbulbs as a Source of Electricity Saving in Buildings

    Directory of Open Access Journals (Sweden)

    Zeb Akhtar

    2016-01-01

    Full Text Available Today a number of renewable energy technologies are available for power generation, but fossil fuels are still providing a dominant share nevertheless. In order to decrease the electric bill and save our environment, energy conservation is always crucial. In this paper a very interesting idea is presented which is economically viable to reduce electricity usage in our buildings. An effort has been made to estimate the amount of energy that could be saved in the dormitory section of the IMOP building in Russia. Although there are many ways to reduce the consumption of electricity in this building but here the emphasis is on changing light bulbs inside the rooms, kitchen, toilet and bathroom of each apartment. The scope of the study is to figure out monthly electricity saving by replacing traditional light bulbs by LED light bulbs in the building under consideration. The total investment required and the payback period is also presented.

  2. Scandium oxide antireflection coatings for superluminescent LEDs

    Science.gov (United States)

    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.

  3. First African-led experiment at CERN

    CERN Multimedia

    2017-01-01

    The first African-led experiment has taken place at CERN, supported by UK researchers. Students and staff from the University of the Western Cape, South Africa, have investigated the isotope Selenium 70 using Isolde, CERN’s nuclear physics facility. The nucleus of the isotope is known to have two possible shapes depending on its excitation state, and the team wanted to examine the relationship between shape and energy more closely. South Africa joined the Isolde collaboration in March 2017 to benefit from HIE-Isolde’s beams of unstable, exotic particles. The selenium 70 experiment, using Miniball, is the first to be approved. Students and staff explain more about the experiment, and why coming to CERN is so important for science in South Africa.

  4. Switched-capacitor isolated LED driver

    Energy Technology Data Exchange (ETDEWEB)

    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. LED-Based Colour Sensing System

    Directory of Open Access Journals (Sweden)

    Ibrahim AL-BAHADLY

    2010-03-01

    Full Text Available This paper presents a new colour sensing system for measuring the colour of car paint accurately enough to reproduce the paint proportions to cover up scratches or wear on a car. The aim is to repaint a car’s damaged area at a fraction of the cost of repainting the whole car. The proposed colour sensing system is based on Light Emitting Diode (LED. A prototype for the system has been designed, built, and tested. During this work light was researched as well as lighting sources, how light travels, how light reflects and refracts, ways light can be quantized, the human eye, why cameras look accurate, lighting conditions and their effects, and the emergence of colour.

  6. Progress and prospects of GaN-based LEDs using nanostructures

    Science.gov (United States)

    Zhao, Li-Xia; Yu, Zhi-Guo; Sun, Bo; Zhu, Shi-Chao; An, Ping-Bo; Yang, Chao; Liu, Lei; Wang, Jun-Xi; Li, Jin-Min

    2015-06-01

    Progress with GaN-based light emitting diodes (LEDs) that incorporate nanostructures is reviewed, especially the recent achievements in our research group. Nano-patterned sapphire substrates have been used to grow an AlN template layer for deep-ultraviolet (DUV) LEDs. One efficient surface nano-texturing technology, hemisphere-cones-hybrid nanostructures, was employed to enhance the extraction efficiency of InGaN flip-chip LEDs. Hexagonal nanopyramid GaN-based LEDs have been fabricated and show electrically driven color modification and phosphor-free white light emission because of the linearly increased quantum well width and indium incorporation from the shell to the core. Based on the nanostructures, we have also fabricated surface plasmon-enhanced nanoporous GaN-based green LEDs using AAO membrane as a mask. Benefitting from the strong lateral SP coupling as well as good electrical protection by a passivation layer, the EL intensity of an SP-enhanced nanoporous LED was significantly enhanced by 380%. Furthermore, nanostructures have been used for the growth of GaN LEDs on amorphous substrates, the fabrication of stretchable LEDs, and for increasing the 3-dB modulation bandwidth for visible light communication. Project supported by the National Natural Science Foundation of China (Grant No. 61334009), the National High Technology Research and Development Program of China (Grant Nos. 2015AA03A101 and 2014BAK02B08), China International Science and Technology Cooperation Program (Grant No. 2014DFG62280), the “Import Outstanding Technical Talent Plan” and “Youth Innovation Promotion Association Program” of the Chinese Academy of Sciences.

  7. GATEWAY Demonstrations: LED System Performance in a Trial Installation--Two Years Later, Yuma Border Patrol, Yuma, Arizona

    Energy Technology Data Exchange (ETDEWEB)

    Wilkerson, Andrea M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sullivan, Gregory P. [Efficiency Solutions, Inc., Richland, WA (United States); Davis, Robert G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-04-01

    Along the Yuma Sector Border Patrol Area in Yuma, Arizona, the GATEWAY program conducted a trial demonstration in which the incumbent quartz metal halide area lighting was replaced with LED at three pole locations at the Yuma Sector Border Patrol Area in Yuma, Arizona. The retrofit was documented to better understand LED technology performance in high-temperature environments. This report follows the GATEWAY Yuma Phase 1.1 Report and reflects LED system results documented two years after the demonstration began.

  8. GATEWAY Demonstrations: LED System Performance in a Trial Installation--One Year Later, Yuma Border Patrol, Yuma, Arizona

    Energy Technology Data Exchange (ETDEWEB)

    Wilkerson, A. M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Davis, R. G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-04-01

    Along the Yuma Sector Border Patrol Area in Yuma, Arizona, the GATEWAY program conducted a trial demonstration in which the incumbent quartz metal halide area lighting was replaced with LED at three pole locations at the Yuma Sector Border Patrol Area in Yuma, Arizona. The retrofit was documented to better understand LED technology performance in high-temperature environments. This report follows the GATEWAY Yuma Phase 1.0 Report and reflects LED system results documented one year after the demonstration began.

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Jens B Bosse

    Full Text Available 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.

  11. LED 扩散板光扩散的性能评价的研究%Study on the Light Diffusion Performance Evaluation of LED Diffusion Plate

    Institute of Scientific and Technical Information of China (English)

    彭文利

    2013-01-01

      LED 扩散板光扩散的性能评价是根据环境要求和不同场所照度标准要求,利用 LED 扩散板光扩散的性能(如照度均匀度、眩光限制、光源颜色、显色性、反射比等),生产出具备一定柔和舒适度的 LED 照明灯具,制造出符合室内照明要求的气氛照明、情景照明、情调照明,满足用户的各种照明要求,其造型也要符合用户的审美观,最主要的是符合能源高效的利用。这项技术的成功研制将会使我国 LED 灯具在 LED 国际市场的竞争中处于优势地位,打开国际市场。这项技术的成功研制也填补了行业内无 LED 扩散板光扩散的性能评价体系的一个空白。%The light diffusion performance evaluation of LED diffusion plate is based on the environmental requirements and standards requirements in different places. The use of the light diffusion properties (e.g., uniformity of illumination, glare limitation, the light source color, the color, reflectance, etc.) of LED diffusion plate can product the LED light with soft comfort. It can create the mood lighting, scene lighting and mood lighting meeting the indoor lighting requirements and the user's requirements, and its shape is also in line with the aesthetics of the user, the most important is compliance with the energy efficient use. The success of this technology will make China's LED lamps in a dominant position in the LED international market competition, and open the international market. And it also will fill a blank of the light diffusion performance evaluation system of LED diffuser plate.

  12. LED 蓝光危害研究%Research of LED Blue Light Hazard

    Institute of Scientific and Technical Information of China (English)

    赵介军; 乔波; 过峰

    2015-01-01

    随着人们对于照明产品光生物效应的关注, LED照明产品的光生物辐射安全问题,尤其是视网膜蓝光危害已成为人们对于LED产品望而却步的一个重要原因。通过研究LED的蓝光危害,分析了LED蓝光危害产生的原因和可能对人体造成的伤害。并通过实验调研市场上LED照明产品的蓝光危害现状,阐述了如何正确的使用LED产品,从而有效避免蓝光辐射危害。%LED lighting products with its beneficial characteristics, such as energy saving, environmental protection, long life, small size, and etc, have gradually entered people’s life.People started to care about the photobiological effects of lighting products.The photobiological radiation safety of LED lighting products, especially the retinal blue light hazard has become an important reason why people do not choose LED products. This paper analyzed the reasons and their possible harms to the human body which may be caused by LED blue light hazard.And by performing research on current situation of LED lighting products blue light hazard in market, it described how to properly use LED products so as to effectively prevent blue light hazards.

  13. Experimentally comparing the attractiveness of domestic lights to insects: Do LEDs attract fewer insects than conventional light types?

    Science.gov (United States)

    Wakefield, Andrew; Broyles, Moth; Stone, Emma L; Jones, Gareth; Harris, Stephen

    2016-11-01

    LED lighting is predicted to constitute 70% of the outdoor and residential lighting markets by 2020. While the use of LEDs promotes energy and cost savings relative to traditional lighting technologies, little is known about the effects these broad-spectrum "white" lights will have on wildlife, human health, animal welfare, and disease transmission. We conducted field experiments to compare the relative attractiveness of four commercially available "domestic" lights, one traditional (tungsten filament) and three modern (compact fluorescent, "cool-white" LED and "warm-white" LED), to aerial insects, particularly Diptera. We found that LEDs attracted significantly fewer insects than other light sources, but found no significant difference in attraction between the "cool-" and "warm-white" LEDs. Fewer flies were attracted to LEDs than alternate light sources, including fewer Culicoides midges (Diptera: Ceratopogonidae). Use of LEDs has the potential to mitigate disturbances to wildlife and occurrences of insect-borne diseases relative to competing lighting technologies. However, we discuss the risks associated with broad-spectrum lighting and net increases in lighting resulting from reduced costs of LED technology.

  14. How Molecular Evolution Technologies can Provide Bespoke Industrial Enzymes: Application to Biofuels Comment les technologies d’évolution moléculaire peuvent fournir des enzymes industrielles sur mesure : application aux biocarburants

    Directory of Open Access Journals (Sweden)

    Fourage L.

    2013-08-01

    Full Text Available Enzymatic hydrolysis of lignocellulose is one of the major bottlenecks in the development of biological conversion of lignocellulosic biomass to biofuels. One of the most efficient organisms for the production of cellulolytic enzymes is the fungus Trichoderma reesei, mainly thanks to its high secretion capacity. The conversion of cellulose to glucose involves three types of cellulases working in synergy: endoglucanases (EC 3.2.1.4 randomly cleave 13-1,4 glycosidic linkages of cellulose, cellobiohydrolases (EC 3.2.1.91 attack cellulose chain ends to produce cellobiose dimers which are converted into glucose by the 13-glucosidases (EC 3.2.1 21. Unexpectedly, the amount of l3-glucosidase (BGLI from T. reesei hyperproducing strains represents a very low percentage of the total secreted proteins. A suboptimal content of this enzyme limits the performance of commercial cellulase preparations as cellobiose represents the main inhibitor of the cellulolysis reaction by cellobiohydrolases. This bottleneck can be alleviated either by overexpressing the f3-glucosidase in T. reesei or optimized its specific activity. After giving a brief overview of the main available technologies, this example will be used to illustrate the potential of directed evolution technologies to devolop enzymes tailored to fit industrial needs. We describe the L-ShuffiingTM strategy implemented with three parental genes originating from microbial biodiversity leading to identification of an efficient 13-glucosidase showing a 242 fold increase in specific activity for the pNPGIc substrate compared to WT (Wild Type Cel3a beta-glucosidase of T. reesei. After expression of the best improved 13-glucosidase in T. reesei and secretion of a new enzymatic cocktail, improvement of the glucosidase activity allows a 4-fold decrease of cellulase loading for the saccharification of an industrial pretreated biomass compared to the parental cocktail. L’hydrolyse enzymatique de la lignocellulose

  15. New paradigm of multi-chip white LEDs: combination of an InGaN blue LED and full down-converted phosphor-converted LEDs.

    Science.gov (United States)

    Oh, Ji Hye; Oh, Jeong Rok; Park, Hoo Keun; Sung, Yeon-Goog; Do, Young Rag

    2011-05-09

    This study introduces innovative multi-chip white LED systems that combine an InGaN blue LED and green/red or green/amber/red full down-converted, phosphor-conversion LEDs (pc-LEDs). Efficient green, amber, and red full down-converted pc-LEDs were fabricated by simply capping a long-wave pass filter (LWPF) on top of LED packing associated with each corresponding powder phosphor. The principal advantage of this type of color-mixing approach in newly developed multi-chip white LEDs based on colored pc-LEDs is thought to be dynamic control of the chromaticity and better light quality. In addition, the color-mixing approach improves the low efficacy of green/amber LEDs in the "green gap" wavelength; reduces the wide color/efficacy variations of each primary LED with at different temperatures and currents; and improves the low color rendering indexes of the traditional color-mixing approach in red, green, and blue (RGB) multi-chip white LEDs.

  16. The PV LED Engine - a new generation of intelligent solar powered LED lighting

    DEFF Research Database (Denmark)

    Poulsen, Peter Behrensdorff; Thorsteinsson, Sune

    to dispose intelligently over the energy.To validate the model high-end PV products on the market has been bought, simulated and thewhole electrical system been characterized electrically (battery, LED, electrical circuit, PV) and optical properties of the optical system in front of the solar panel...

  17. Factors that led to the Walkerton tragedy.

    Science.gov (United States)

    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.

  18. Led Astray by Hemoglobin A1c

    Directory of Open Access Journals (Sweden)

    Jean Chen MD

    2016-01-01

    Full Text Available 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.

  19. LED-based digital diameter measurement

    Science.gov (United States)

    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.

  20. 对等网络技术的新发展——JXTA%A Promising Evolution of P2P Technologies--JXTA

    Institute of Scientific and Technical Information of China (English)

    黄小琴; 黎星星; 朱庆生

    2003-01-01

    With the explosion of content on the network and quantities of devices connected, it is urgently required todevelop the P2P technologies. Thus, JXTA, a new P2P technology, emerged as the times require. This paper ex-plores P2P and JXTA in particular, and then gives an applied example about it. At last, similarities and differencesbetween JXTA and other typical distributed computing technologies and their application ranges have been deeply in-vestigated.

  1. Carrier transport in dichromatic color-coded semipolar (2021) and (2021) III-N LEDs

    Science.gov (United States)

    Kisin, Mikhail V.; Huang, Chih-Li; El-Ghoroury, Hussein S.

    2014-03-01

    Simulation of III-nitride color-coded multiple quantum well (MQW) LED structures was performed using as an experimental benchmark dichromatic semipolar LEDs grown in Ga-polar and N-polar crystallographic orientations (Y. Kawaguchi et.al, APL 100, 231110, 2012). Different QW depths in the color-coded LEDs and opposite interface polarization charges in Ga-polar and N-polar structures provide different conditions for carrier transport across the LED active regions. Combination of several effects was crucial for adequate reproduction of the emission spectra experimentally observed in color-coded structures with violet-aquamarine and aquamarine-violet active region layouts. A standard drift-diffusion transport model wascompleted with rate equations for nonequilibrium QW populations and several high-energy transport features, including the effects of QW carrier overshoot and Auger-assisted QW depopulation. COMSOL-based Optoelectronic Device Modeling Software (ODMS) developed at Ostendo Technologies Inc. was utilized for device simulation.

  2. Free-form thin lens design with light scattering surfaces for practical LED down light illumination

    Science.gov (United States)

    Lin, Raychiy J.; Sun, Ching-Cherng

    2016-05-01

    The free-form optical quasilens surface technology was utilized to develop and design a solid transparent plastic optical lens for the LED down light with the narrow angular light distribution requirement in the LED lighting applications. In order to successfully complete the mission, the precise mid-field angular distribution model of the LED light source was established and built. And also the optical scattering surface property of the Harvey BSDF scattering model was designed, measured, and established. Then, the optical simulation for the entire optical system was performed to develop and design this solid transparent plastic optical lens system. Finally, the goals of 40 deg angular light distribution pattern defined at full width half maximum with glare reduced in the areas of interest and the optical performance of nearly 82% light energy transmission optics were achieved for the LED down light illumination.

  3. Scalable, Economical Fabrication Processes for Ultra-Compact Warm-White LEDs

    Energy Technology Data Exchange (ETDEWEB)

    Lowes, Ted [Cree, Inc., Durham, NC (United States)

    2016-01-31

    Conventional warm-white LED component fabrication consists of a large number of sequential steps which are required to incorporate electrical, mechanical, and optical functionality into the component. Each of these steps presents cost and yield challenges which multiply throughout the entire process. Although there has been significant progress in LED fabrication over the last decade, significant advances are needed to enable further reductions in cost per lumen while not sacrificing efficacy or color quality. Cree conducted a focused 18-month program to develop a new low-cost, high-efficiency light emitting diode (LED) architecture enabled by novel large-area parallel processing technologies, reduced number of fabrication steps, and minimized raw materials use. This new scheme is expected to enable ultra-compact LED components exhibiting simultaneously high efficacy and high color quality. By the end of the program, Cree fabricated warm-white LEDs with a room-temperature “instant on” efficacy of >135 lm/W at ~3500K and 90 CRI (when driven at the DOE baseline current density of 35 A/cm2). Cree modified the conventional LED fabrication process flow in a manner that is expected to translate into simultaneously high throughput and yield for ultra-compact packages. Building on its deep expertise in LED wafer fabrication, Cree developed these ultra-compact LEDs to have no compromises in color quality or efficacy compared to their conventional counterparts. Despite their very small size, the LEDs will also be robustly electrically integrated into luminaire systems with the same attach yield as conventional packages. The versatility of the prototype high-efficacy LED architecture will likely benefit solid-state lighting (SSL) luminaire platforms ranging from bulbs to troffers. We anticipate that the prototype LEDs will particularly benefit luminaires with large numbers of distributed compact packages, such as linear and area luminaires (e.g. troffers). The fraction of

  4. Micro-LED arrays: a tool for two-dimensional neuron stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Poher, V; Kennedy, G T; French, P M W; Neil, M A A [Blackett Laboratory, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom); Grossman, N; Nikolic, K; Drakakis, E M; Degenaar, P [Institute of Biomedical Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom); Zhang, H X; Gong, Z; Gu, E; Dawson, M D [Institute of Photonics, University of Strathclyde, 106 Rottenrow, Glasgow G4 0NW (United Kingdom)], E-mail: vincent.poher@imperial.ac.uk

    2008-05-07

    Stimulating neuron cells with light is an exciting new technology that is revolutionizing the neurosciences. To date, due to the optical complexity that is involved, photostimulation has only been achieved at a single site using high power light sources. Here we present a GaN based micro-light emitting diode (LED) array that can open the way to multi-site photostimulation of neuron cells. The device is a two-dimensional array of micrometre size LED emitters. Each emitter has the required wavelength, optical power and modulation bandwidth to trigger almost any photosensitizer and is individually addressable. We demonstrate micrometre resolution photoactivation of a caged fluorophore and photostimulation of sensitized living neuron cells. In addition, a complete system that combines the micro-LED array with multi-site electrophysiological recording based on microelectrode array technology and/or fluorescence imaging is presented.

  5. Determining contrast sensitivity functions for monochromatic light emitted by high-brightness LEDs

    Science.gov (United States)

    Ramamurthy, Vasudha; Narendran, Nadarajah; Freyssinier, Jean Paul; Raghavan, Ramesh; Boyce, Peter

    2004-01-01

    Light-emitting diode (LED) technology is becoming the choice for many lighting applications that require monochromatic light. However, one potential problem with LED-based lighting systems is uneven luminance patterns. Having a uniform luminance distribution is more important in some applications. One example where LEDs are becoming a viable alternative and luminance uniformity is an important criterion is backlighted monochromatic signage. The question is how much uniformity is required for these applications. Presently, there is no accepted metric that quantifies luminance uniformity. A recent publication proposed a method based on digital image analysis to quantify beam quality of reflectorized halogen lamps. To be able to employ such a technique to analyze colored beams generated by LED systems, it is necessary to have contrast sensitivity functions (CSFs) for monochromatic light produced by LEDs. Several factors including the luminance, visual field size, and spectral power distribution of the light affect the CSFs. Although CSFs exist for a variety of light sources at visual fields ranging from 2 degrees to 20 degrees, CSFs do not exist for red, green, and blue light produced by high-brightness LEDs at 2-degree and 10-degree visual fields and at luminances typical for backlighted signage. Therefore, the goal of the study was to develop a family of CSFs for 2-degree and 10-degree visual fields illuminated by narrow-band LEDs at typical luminances seen in backlighted signs. The details of the experiment and the results are presented in this manuscript.

  6. Surface Evolution during MBE Growth

    Science.gov (United States)

    Orme, C.; Orr, B. G.

    The evolution of surfaces grown using molecular beam epitaxy (MBE) is an interesting scientific issue as well as an important technological concern. In this review article we examine surface evolution during film growth from several different points of view. Experimental, simulational and analytical descriptions of the process are discussed.

  7. Software Architecture Evolution

    Science.gov (United States)

    Barnes, Jeffrey M.

    2013-01-01

    Many software systems eventually undergo changes to their basic architectural structure. Such changes may be prompted by new feature requests, new quality attribute requirements, changing technology, or other reasons. Whatever the causes, architecture evolution is commonplace in real-world software projects. Today's software architects, however,…

  8. Evolution of Business Models

    DEFF Research Database (Denmark)

    Antero, Michelle C.; Hedman, Jonas; Henningsson, Stefan

    2013-01-01

    The ERP industry has undergone dramatic changes over the past decades due to changing market demands, thereby creating new challenges and opportunities, which have to be managed by ERP vendors. This paper inquires into the necessary evolution of business models in a technology-intensive industry (e......, by adopting different value configurations to reflect the convergence of customers, suppliers and vendors....

  9. Software Architecture Evolution

    Science.gov (United States)

    Barnes, Jeffrey M.

    2013-01-01

    Many software systems eventually undergo changes to their basic architectural structure. Such changes may be prompted by new feature requests, new quality attribute requirements, changing technology, or other reasons. Whatever the causes, architecture evolution is commonplace in real-world software projects. Today's software architects, however,…

  10. Student-Led Engagement of Journal Article Authors in the Classroom Using Web-Based Videoconferencing

    Science.gov (United States)

    Stockman, Brian J.

    2015-01-01

    The learning environment described here uses Web-based videoconferencing technology to merge the traditional classroom journal article discussion with student-led interviews of journal article authors. Papers that describe recent applications of a given technique are selected, with the author engagement occurring at the end of a three or four week…

  11. Organisational Modalities of Farmer-led Irrigation Development in Tsangano District, Mozambique

    NARCIS (Netherlands)

    Nkoka, F.; Veldwisch, G.J.A.; Bolding, J.A.

    2014-01-01

    This paper examines the organisational modalities of farmer-led irrigation systems in Tsangano, Mozambique, which has expanded over large areas with minimal external support. By looking at their historic development trajectories and the integrated nature of land and water resources, technological ob

  12. Organisational Modalities of Farmer-led Irrigation Development in Tsangano District, Mozambique

    NARCIS (Netherlands)

    Nkoka, F.; Veldwisch, G.J.A.; Bolding, J.A.

    2014-01-01

    This paper examines the organisational modalities of farmer-led irrigation systems in Tsangano, Mozambique, which has expanded over large areas with minimal external support. By looking at their historic development trajectories and the integrated nature of land and water resources, technological

  13. Improving Student Achievement in Introductory Computer Science Courses Using Peer-Led Team Learning

    Science.gov (United States)

    Dennis, Sonya Maria

    2013-01-01

    There has been a steady decline of majors in the disciplines of science, technology, engineering, and mathematics ("STEM majors"). In an effort to improve recruitment and retention in "STEM" majors, an active-learning methodology--"peer-led team learning" ("PLTL")--was implemented by the participating…

  14. Validating Community-Led Forest Biomass Assessments.

    Science.gov (United States)

    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.

  15. 基于技术进化理论的破坏性创新预测与实现模型%Model for Roadmapping Disruptive Innovation Based on Technology Evolution Theory

    Institute of Scientific and Technical Information of China (English)

    孙建广; 檀润华; 江屏

    2012-01-01

    破坏性创新是一种便宜、方便、简单的产品技术创新,它的实现可以使企业技术实现有效增长,也可以利用其开发出的新产品创立新的企业.由于现有破坏性创新预测与实现方法无法有效地对破坏性技术进行搜索,在激烈的市场竞争中,对于处于成熟期的产品,有效的新产品开发变得极为困难.基于破坏性创新的发生条件,对破坏性创新的预测与产生方法进行了深入研究,为了考察破坏性技术的可预测性,研究技术进化路线上的破坏性创新节点及其破坏性创新的技术进化过程,建立了新市场破坏创新和低端破坏创新的详细的实现模型.所提出的方法既可用于新兴企业的新产品开发,也可用于市场主流企业的未来技术规划.%Disruptive innovation (DI) is a kind of technology innovation which is cheaper, better, and more convenient. DI can create enterprise technology growth and establish entirely new enterprises through its newly developed products. Because existing Disruptive innovation roadmapping can't search for disruptive technologies effectively, to develop effective new products in the maturity period becomes quite difficult, in intensive of fierce market competition. DI roadmapping is in-depth studied based on the occurring conditions of DI. hi order to investigate the predictability of disruptive technology, me disruptive bifurcation points on technological evolution path and the technological evolution process of DI are discussed. Finally, detailed process models of new-market DI and low-end DI are established. This methodology can be used for both developing new products of newly built enterprises and helping more senior enterprises to predict the future of technologies.

  16. Cultural Evolution and SETI

    Science.gov (United States)

    Dick, S. J.

    2009-12-01

    The Drake Equation for the number of radio communicative technological civilizations in the Galaxy encompasses three components of cosmic evolution: astronomical, biological and cultural. Of these three, cultural evolution totally dominates in terms of the rapidity of its effects. Yet, SETI scientists do not take cultural evolution into account, perhaps for understandable reasons, since cultural evolution is not well-understood even on Earth and is unpredictable in its outcome. But the one certainty for technical civilizations billions, millions, or even thousands of years older than ours is that they will have undergone cultural evolution. Cultural evolution potentially takes place in many directions, but this paper argues that its central driving force is the maintenance, improvement and perpetuation of knowledge and intelligence, and that to the extent intelligence can be improved, it will be improved. Applying this principle to life in the universe, extraterrestrials will have sought the best way to improve their intelligence. One possibility is that they may have long ago advanced beyond flesh-and-blood to artificial intelligence, constituting a postbiological universe. Although this subject has been broached, it has not been given the attention it is due from its foundation in cultural evolution. Nor has the idea of a postbiological universe been carried to its logical conclusion, including a careful analysis of the implications for SETI. SETI scientists, social scientists, and experts in AI should consider the strengths and weaknesses of this new paradigm.

  17. Dicing of high-power white LEDs in heat sinks with the water jet-guided laser

    Science.gov (United States)

    Mai, Tuan Anh; Housh, Roy; Brulé, Arnaud; Richerzhagen, Bernold

    2007-02-01

    High-brightness LEDs are compound semiconductor devices and distinguish themselves from conventional LEDs by their exceptional luminosity. Today they are increasingly used as light sources, replacing conventional incandescent and fluorescent lamp technologies. HB LEDs are difficult to manufacture, as they must be grown by sophisticated epitaxial growth techniques such as MOCVD. They are packaged like power semiconductors, using surface mount technology and thermal pads. After having been successfully applied to GaN scribing for side-emitting LEDs, the Laser MicroJet (R) is used today for cutting heat sinks of HB white LEDs. Due to the high-emitted light power, the generated heat must be dissipated through a heat sink. Materials typically employed are metals with high heat conductivity, notably CuW and molybdenum. Applying the Laser MicroJet (R) the achieved cutting quality in these metals is outstanding - smooth edges, no contamination, no burrs, no heat damage, no warping - all this at high speed.

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

    Science.gov (United States)

    Naeser, Margaret A.; Saltmarche, Anita; Krengel, Maxine H.; Hamblin, Michael R.; Knight, Jeffrey A.

    2010-02-01

    Two chronic, traumatic brain injury (TBI) cases are presented, where cognitive function improved following treatment with transcranial light emitting diodes (LEDs). At age 59, P1 had closed-head injury from a motor vehicle accident (MVA) without loss of consciousness and normal MRI, but unable to return to work as development specialist in internet marketing, due to cognitive dysfunction. At 7 years post-MVA, she began transcranial LED treatments with cluster heads (2.1" diameter with 61 diodes each - 9x633nm, 52x870nm; 12-15mW per diode; total power, 500mW; 22.2 mW/cm2) on bilateral frontal, temporal, parietal, occipital and midline sagittal areas (13.3 J/cm2 at scalp, estimated 0.4 J/cm2 to brain cortex per area). Prior to transcranial LED, focused time on computer was 20 minutes. After 2 months of weekly, transcranial LED treatments, increased to 3 hours on computer. Performs nightly home treatments (now, 5 years, age 72); if stops treating >2 weeks, regresses. P2 (age 52F) had history of closed-head injuries related to sports/military training and recent fall. MRI shows fronto-parietal cortical atrophy. Pre-LED, was not able to work for 6 months and scored below average on attention, memory and executive function. Performed nightly transcranial LED treatments at home (9 months) with similar LED device, on frontal and parietal areas. After 4 months of LED treatments, returned to work as executive consultant, international technology consulting firm. Neuropsychological testing (post- 9 months of transcranial LED) showed significant improvement in memory and executive functioning (range, +1 to +2 SD improvement). Case 2 reported reduction in PTSD symptoms.

  19. [Analysis of color gamut of LCD system based on LED backlight with area-controlling technique].

    Science.gov (United States)

    Li, Fu-Wen; Jin, Wei-Qi; Shao, Xi-Bin; Zhang, Li-Lei; Wan, Li-Fang

    2010-05-01

    Color gamut as a significant performance index for display system describes the color reproduction ability IN real scenes. Liquid crystal display (LCD) is the most popular technology in flat panel display. However, conventional cold cathode fluorescent lamp (CCFL) backlight of LCD can not behave high color gamut compared with cathode ray tube (CRT). The common used method of color gamut measuring for LCD system is introduced at the beginning. According to the inner structure and display principle of LCD system, there are three major factors deciding LCD's color gamut: spectral properties of backlight, transmittance properties of color filters and performance of liquid crystal panel. Instead of conventional backlight CCFL, RGB-LED backlight is used for improving color reproduction of LCD display system. Due to the imperfect match between RGB-LED' s spectra and color filter's transmittance, the color filter would reduce the color gamut of LCD system more or less. Therefore, LCD system based on LED backlight with area-control technique is introduced which modifies backlight control signal according to the input signal After analyzing and calculating the spectra of LED backlight which passes through the color filters using method of colorimetry, the area sizes of color gamut triangles of RGB-LED backlight with area-control and RGB-LED backlight without area-control LCD systems are compared and the relationship between color gamut and varying contrast of liquid crystal panel is analyzed. It is indicated that LED backlight with area-control technique can avoid color saturation dropping and have little effects on the contrast variation of liquid crystal panel. In other words, LED backlight with area-control technique relaxes the requirements of both color filter performance and liquid crystal panel. Thus, it is of importance to improve the color gamut of the current LCD system with area-control LED backlight.

  20. Public outreach: (R)evolution by the lakeside

    CERN Multimedia

    2006-01-01

    Why do the planets revolve around the Sun? Has genetic science shaken Darwin's theories to their foundations? Are viruses the champions of evolution? Is progress a form of tradition? On 8 and 9 July, Geneva's Science History Museum is inviting you to a Science Night on the theme of 'Evolution, revolution'. The Sixth Science Night will host some 60 stands and offer workshops for children, guided tours, exhibitions and shows. Anticipating the (r)evolutions from the LHC, CERN will also be taking part in the event. The future accelerator promises to deliver scientific advances and may even turn our understanding of the infinitesimally small on its head. However, the LHC has already led to technological breakthroughs. The Laboratory's stand will put a special emphasis on the part played by CERN in the computing revolution, from the Web to the Computing Grid. Computer animations will be used to explain these technologies which have spin-offs well beyond the field of particle physics that are of benefit to the whol...

  1. Patients' views on a nurse-led prostate clinic.

    Science.gov (United States)

    Townsend, Alison

    Nurse-led clinics are being established in a number of specialties including urology. Men attending a nurse-led clinic for suspected prostate cancer were surveyed to investigate their perception of and satisfaction with a nurse-led clinic and to establish whether this model of care met expectations. The results showed that patients were satisfied with the service. This adds to the growing body of evidence supporting nurse-led services.

  2. Behavioral fluency: Evolution of a new paradigm.

    Science.gov (United States)

    Binder, C

    1996-01-01

    Behavioral fluency is that combination of accuracy plus speed of responding that enables competent individuals to function efficiently and effectively in their natural environments. Evolving from the methodology of free-operant conditioning, the practice of precision teaching set the stage for discoveries about relations between behavior frequency and specific outcomes, notably retention and maintenance of performance, endurance or resistance to distraction, and application or transfer of training. The use of frequency aims in instructional programming by Haughton and his associates led to formulation of empirically determined performance frequency ranges that define fluency. Use of fluency-based instructional methods has led to unprecedented gains in educational cost effectiveness, and has the potential for significantly improving education and training in general. This article traces the development of concepts, procedures, and findings associated with fluency and discusses their implications for instructional design and practice. It invites further controlled research and experimental analyses of phenomena that may be significant in the future evolution of educational technology and in the analysis of complex behavior.

  3. A COGNITIVE AND MEMETIC SCIENCE APPROACH TO ANALYZE THE HUMAN FACTORS IN PREDICTING THE EVOLUTION OF PAPER TECHNOLOGY AND PRODUCTS IN THE 21sT CENTURY

    Institute of Scientific and Technical Information of China (English)

    FumihikoONABE

    2004-01-01

    Predicting the future of paper industry is conventionally conducted from the technological and market-oriented aspects as well as a variety of constraints lying ahead of the industry such as resource, energy, and environmental issues.

  4. Thermal design for the high-power LED lamp

    Energy Technology Data Exchange (ETDEWEB)

    Tian Xiaogai; Chen Wei; Zhang Jiyong, E-mail: tianxiaogai@sina.com [NVC Lighting Technology Corporation Research and Development Center (Shanghai), Shanghai 201112 (China)

    2011-01-15

    This paper summarizes different kinds of heat sinks on the market for high power LED lamps. Analysis is made on the thermal model of LED, PCB and heat sink separately with a simplified mode provided. Two examples of simulation are illustrated as a demonstration for the thermal simulation as guidance for LED lamp design. (semiconductor devices)

  5. A review of passive thermal management of LED module

    NARCIS (Netherlands)

    Ye, H.; Sau, K.; Zeijl, H. van; Gielen, A.W.J.; Zhang, G.

    2011-01-01

    Recently, the high-brightness LEDs have begun to be designed for illumination application. The increased electrical currents used to drive LEDs lead to thermal issues. Thermal management for LED module is a key design parameter as high operation temperature directly affects their maximum light outpu

  6. Modelling intelligence-led policing to identify its potential

    NARCIS (Netherlands)

    Hengst-Bruggeling, M. den; Graaf, H.A.L.M. de; Scheepstal, P.G.M. van

    2014-01-01

    lntelligence-led policing is a concept of policing that has been applied throughout the world. Despite some encouraging reports, the effect of intelligence-led policing is largely unknown. This paper presents a method with which it is possible to identify intelligence-led policing's potential to

  7. EC-LEDS Supports the Low-Carbon Transition

    Energy Technology Data Exchange (ETDEWEB)

    2016-09-01

    EC-LEDS is a flagship U.S. government-led effort that assists countries to create and implement low emission development strategies, or LEDS -- development frameworks that promote sustainable social and economic development while reducing greenhouse gas emissions over the medium to long term.

  8. Modelling intelligence-led policing to identify its potential

    NARCIS (Netherlands)

    Hengst-Bruggeling, M. den; Graaf, H.A.L.M. de; Scheepstal, P.G.M. van

    2014-01-01

    lntelligence-led policing is a concept of policing that has been applied throughout the world. Despite some encouraging reports, the effect of intelligence-led policing is largely unknown. This paper presents a method with which it is possible to identify intelligence-led policing's potential to inc

  9. A new lifetime estimation model for a quicker LED reliability prediction

    Science.gov (United States)

    Hamon, B. H.; Mendizabal, L.; Feuillet, G.; Gasse, A.; Bataillou, B.

    2014-09-01

    LED reliability and lifetime prediction is a key point for Solid State Lighting adoption. For this purpose, one hundred and fifty LEDs have been aged for a reliability analysis. LEDs have been grouped following nine current-temperature stress conditions. Stress driving current was fixed between 350mA and 1A and ambient temperature between 85C and 120°C. Using integrating sphere and I(V) measurements, a cross study of the evolution of electrical and optical characteristics has been done. Results show two main failure mechanisms regarding lumen maintenance. The first one is the typically observed lumen depreciation and the second one is a much more quicker depreciation related to an increase of the leakage and non radiative currents. Models of the typical lumen depreciation and leakage resistance depreciation have been made using electrical and optical measurements during the aging tests. The combination of those models allows a new method toward a quicker LED lifetime prediction. These two models have been used for lifetime predictions for LEDs.

  10. Study on the mechanism of color coordinate shift of LED package

    Science.gov (United States)

    Zhuang, Yunyi; Wang, Yong; Yang, Bobo; Li, Zhanguo; Yang, Lei; Zou, Jun

    2017-07-01

    In the paper, the influences of the chip, silicone and phosphors on the color coordinate shift of LED were studied. In the process of LED baking, it was found that the effect of the chip and silicone on the color coordinate drift is less than 3% through the analysis of each influencing factor. But the influence of the phosphors is large and accounted for 11.11% of the overall impact factors. Therefore, it is important to select the better green phosphors in thermal stability for the LED package and it has a guiding significance to the color coordinate of LED distribution. Project supported by the National Natural Science Foundation of China (No. 11474036), the Natural Science Foundation of Shanghai (No. 12ZR1430900), the Shanghai Institute of Technology Talents Scheme (No. YJ2014-04), the Shanghai Municipal Alliance Program (Nos. Lm201514, Lm201505, Lm201455), the Science and Technology Commission of Shanghai Municipality (CN) (No. 14500503300), the Shanghai Cooperative Project (No. ShanghaiCXY-2013-61), and the Jiashan County Technology Program (No. 20141316).

  11. Origin, evolution and genome distribution of microsatellites

    Directory of Open Access Journals (Sweden)

    Eder Jorge Oliveira

    2006-01-01

    Full Text Available Microsatellites, or simple sequence repeats (SSRs, have been the most widely applied class of molecular markers used in genetic studies, with applications in many fields of genetics including genetic conservation, population genetics, molecular breeding, and paternity testing. This range of applications is due to the fact that microsatellite markers are co-dominant and multi-allelic, are highly reproducible, have high-resolution and are based on the polymerase chain reaction (PCR. When first introduced, the development of microsatellite markers was expensive but now new and efficient methods of repetitive sequence isolation have been reported, which have led to reduced costs and microsatellite-technology has been increasingly applied to several species, including non-model organisms. The advent of microsatellite markers revolutionized the use of molecular markers but the development of biometric methods for analyzing microsatellite data has not accompanied the progress in the application of these markers, with more effort being need to obtain information on the evolution of the repetitive sequences, which constitute microsatellites in order to formulate models that fit the characteristics of such markers. Our review describes the genetic nature of microsatellites, the mechanisms and models of mutation that control their evolution and aspects related to their genesis, distribution and transferability between taxa. The implications of the use of microsatellites as a tool for estimating genetic parameters are also discussed.

  12. LED packaging for lighting applications design, manufacturing, and testing

    CERN Document Server

    Liu, Sheng

    2011-01-01

    Since the first light-emitting diode (LED) was invented by Holonyak and Bevacqua in 1962, LEDs have made remarkable progress in the past few decades with the rapid development of epitaxy growth, chip design and manufacture, packaging structure, processes, and packaging materials. LEDs have superior characteristics such as high efficiency, small size, long life, low power consumption, and high reliability. The market for white LED is growing rapidly in various applications. It has been widely accepted that white LEDs will be the fourth illumination source to substitute the incandescent, fluores

  13. Prognostics-based qualification of high-power white LEDs using Lévy process approach

    Science.gov (United States)

    Yung, Kam-Chuen; Sun, Bo; Jiang, Xiaopeng

    2017-01-01

    Due to their versatility in a variety of applications and the growing market demand, high-power white light-emitting diodes (LEDs) have attracted considerable attention. Reliability qualification testing is an essential part of the product development process to ensure the reliability of a new LED product before its release. However, the widely used IES-TM-21 method does not provide comprehensive reliability information. For more accurate and effective qualification, this paper presents a novel method based on prognostics techniques. Prognostics is an engineering technology predicting the future reliability or determining the remaining useful lifetime (RUL) of a product by assessing the extent of deviation or degradation from its expected normal operating conditions. A Lévy subordinator of a mixed Gamma and compound Poisson process is used to describe the actual degradation process of LEDs characterized by random sporadic small jumps of degradation degree, and the reliability function is derived for qualification with different distribution forms of jump sizes. The IES LM-80 test results reported by different LED vendors are used to develop and validate the qualification methodology. This study will be helpful for LED manufacturers to reduce the total test time and cost required to qualify the reliability of an LED product.

  14. VLC-based indoor location awareness using LED light and image sensors

    Science.gov (United States)

    Lee, Seok-Ju; Yoo, Jong-Ho; Jung, Sung-Yoon

    2012-11-01

    Recently, indoor LED lighting can be considered for constructing green infra with energy saving and additionally providing LED-IT convergence services such as visible light communication (VLC) based location awareness and navigation services. For example, in case of large complex shopping mall, location awareness to navigate the destination is very important issue. However, the conventional navigation using GPS is not working indoors. Alternative location service based on WLAN has a problem that the position accuracy is low. For example, it is difficult to estimate the height exactly. If the position error of the height is greater than the height between floors, it may cause big problem. Therefore, conventional navigation is inappropriate for indoor navigation. Alternative possible solution for indoor navigation is VLC based location awareness scheme. Because indoor LED infra will be definitely equipped for providing lighting functionality, indoor LED lighting has a possibility to provide relatively high accuracy of position estimation combined with VLC technology. In this paper, we provide a new VLC based positioning system using visible LED lights and image sensors. Our system uses location of image sensor lens and location of reception plane. By using more than two image sensor, we can determine transmitter position less than 1m position error. Through simulation, we verify the validity of the proposed VLC based new positioning system using visible LED light and image sensors.

  15. Energy-Saving Automation and LED Lighting Systems in Industry, Transport, Building and Municipal Sector

    Directory of Open Access Journals (Sweden)

    V.P. Klimenko

    2013-09-01

    Full Text Available Protocol of diverse technological data unification providing the ability to scale with a minimal increase in auxiliary information volume that allows its usage, ranging from the simplest microcontrollers to integration of automation equipment in global systems was designed for industrial automation systems. Basic technical solutions implemented in development of LED lighting systems of salon subway cars, including a schematic diagram of the lamp, the main technical characteristics of the lamp power supply, the peculiarities of developed design of LED modules are described.

  16. Research on influencing factors of LED frequency response

    Science.gov (United States)

    Luan, Tianyu; Qian, Keyuan

    2017-08-01

    In LED-based visible light communication, the choice of light source device is an important issue. In this paper, the frequency response (FR) of different types of blue LEDs and phosphors is measured. On the basis of that, this paper proposes the FR model of phosphor and supplements the FR model of blue LED. And also, a method is proposed to calculate the FR of phosphor coated LEDs using FR of blue LED and that of phosphor. On this basis, this paper analyses the influencing factors of the FR of blue LED and FR of phosphor respectively. It provides guidance for not only selecting the light source device but also selecting and blending phosphor in visible light communication based on LED.

  17. [Study of achieving white organic LED by fluorescence dye].

    Science.gov (United States)

    Wang, Jin; Wang, Jing; Zheng, Rong-er; Meng, Ji-wu

    2005-08-01

    Some hybrid organic LEDs are made by using fluorescence dye and InGaN blue-light chip and the possibility of achieving white organic LED is investigated according to light conversion theory. Firstly, the LEDs made by normal method and double-dotting glue method are studied. It is found that the double-dotting glue method is too complex and the LEDs made by this way is low-luminance, so it isn't fit to make LED. Secondly the different weight ratio of 1/1/100, 1/1/200, 2/1.5/100 ax-17/zq-13/AB LEDs are manufactured. The 2/1.5/100 LED's color coordinate is (0.32, 0.30), approaching to white point and the correlative color temperature is 6290K which is close to sunlight. So it is a relatively ideal white lamp-house.

  18. LED power reduction trade-offs for ambulatory pulse oximetry.

    Science.gov (United States)

    Peláez, Eduardo Aguilar; Villegas, Esther Rodríguez

    2007-01-01

    The development of ambulatory arterial pulse oximetry is key to longer term monitoring and treatment of cardiovascular and respiratory conditions. The investigation presented in this paper will assist the designer of an ambulatory pulse oximetry monitor in minimizing the overall LED power consumption (P LED,TOT) levels by analyzing the lowest achievable limit as constrained by the optical components, circuitry implementation and final SpO2 reading accuracy required. LED duty cycle (D LED) reduction and light power (P LED,ON) minimization are proposed as methods to reduce P LED,TOT. Bandwidth and signal quality calculations are carried out in order to determine the required P LED,TOT as a function of the different noise sources.

  19. 技术与制度协同演化的理论模型——基于Pelikan模型的扩展%The Theoretical Model of the Co-evolution of Technology and Institutions --The Expansion of the Pelikan' s Model

    Institute of Scientific and Technical Information of China (English)

    焦雨生

    2011-01-01

    The co-evolution of technology and institutions is frontier theory of evolutionary economics, and its general model, which is based on Pelikan model, is starting point to understand the co-evolution of technology and institutions, but this model can not answer the driving forces of co-evolution. The co-evolution of technology and institutions would be a multi level co-evolution, if the technology could be divided into material technology and social technology, and the institutions could be divided into four levels according to Williamson. The driving forces of the co-evolution of technology and institutions is macro inventions, because the macro inventions are exogenous, and can bring significant changes. The process of the driven is a Darwin process to a great extant.%技术与制度的协同演化是现代演化经济学的理论前沿,它的一般模型是由Pelikan发展的。该模型是理解技术和制度协同演化的起点,但没有回答协同演化的动力。如果把技术分为物质技术和社会技术,把制度按照Williamson的分法分为四个层级,技术与制度就会呈现出一种多层级的协同演化。协同演化的驱动力是宏观发明,因其在很大程度上是经济系统外生的,而且能够给整个经济系统带来显著的变化。这个过程更像是一个达尔文过程。

  20. Technical Feasibility Assessment of LED Roadway Lighting on the Golden Gate Bridge

    Energy Technology Data Exchange (ETDEWEB)

    Tuenge, Jason R.

    2012-09-01

    Subsequent to preliminary investigations by the Golden Gate Bridge Highway & Transportation District (GGB), in coordination with Pacific Gas & Electric (PG&E), the GATEWAY Demonstration program was asked to evaluate the technical feasibility of replacing existing roadway lighting on the bridge with products utilizing LED technology. GGB and PG&E also indicated interest in induction (i.e., electrodeless fluorescent) technology, since both light source types feature rated lifetimes significantly exceeding those of the existing high-pressure sodium (HPS) and low-pressure sodium (LPS) products. The goal of the study was to identify any solutions which would reduce energy use and maintenance without compromising the quantity or quality of existing illumination. Products used for roadway lighting on the historic bridge must be installed within the existing amber-lensed shoebox-style luminaire housings. It was determined that induction technology does not appear to represent a viable alternative for the roadway luminaires in this application; any energy savings would be attributable to a reduction in light levels. Although no suitable LED retrofit kits were identified for installation within existing luminaire housings, several complete LED luminaires were found to offer energy savings of 6-18%, suggesting custom LED retrofit kits could be developed to match or exceed the performance of the existing shoeboxes. Luminaires utilizing ceramic metal halide (CMH) were also evaluated, and some were found to offer 28% energy savings, but these products might actually increase maintenance due to the shorter rated lamp life. Plasma technology was evaluated, as well, but no suitable products were identified. Analysis provided in this report was completed in May 2012. Although LED technologies are expected to become increasingly viable over time, and product mock-ups may reveal near-term solutions, some options not currently considered by GGB may ultimately merit evaluation. For

  1. LED-based near infrared sensor for cancer diagnostics

    Science.gov (United States)

    Bogomolov, Andrey; Ageev, Vladimir; Zabarylo, Urszula; Usenov, Iskander; Schulte, Franziska; Kirsanov, Dmitry; Belikova, Valeria; Minet, Olaf; Feliksberger, E.; Meshkovsky, I.; Artyushenko, Viacheslav

    2016-03-01

    Optical spectroscopic technologies are increasingly used for cancer diagnostics. Feasibility of differentiation between malignant and healthy samples of human kidney using Fluorescence, Raman, MIR and NIR spectroscopy has been recently reported . In the present work, a simplification of NIR spectroscopy method has been studied. Traditional high-resolution NIR spectrometry was replaced by an optical sensor based on a set of light-emitting diodes at selected wavelengths as light sources and a photodiode. Two prototypes of the sensor have been developed and tested using 14 in-vitro samples of seven kidney tumor patients. Statistical evaluation of results using principal component analysis and partial least-squares discriminant analysis has been performed. Despite only partial discrimination between tumor and healthy tissue achieved by the presented new technique, the results evidence benefits of LED-based near-infrared sensing used for oncological diagnostics. Publisher's Note: This paper, originally published on 4 March, 2016, was replaced with a corrected/revised version on 7 April, 2016. If you downloaded the original PDF but are unable to access the revision, please contact SPIE Digital Library Customer Service for assistance.

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

    Science.gov (United States)

    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.

  3. Development of high-performance solar LED lighting system

    KAUST Repository

    Huang, B.J.

    2010-08-01

    The present study developed a high-performance charge/discharge controller for stand-alone solar LED lighting system by incorporating an nMPPO system design, a PWM battery charge control, and a PWM battery discharge control to directly drive the LED. The MPPT controller can then be removed from the stand-alone solar system and the charged capacity of the battery increases 9.7%. For LED driven by PWM current directly from battery, a reliability test for the light decay of LED lamps was performed continuously for 13,200 h. It has shown that the light decay of PWM-driven LED is the same as that of constant-current driven LED. The switching energy loss of the MOSFET in the PWM battery discharge control is less than 1%. Three solar-powered LED lighting systems (18 W, 100 W and 150 W LED) were designed and built. The long-term outdoor field test results have shown that the system performance is satisfactory with the control system developed in the present study. The loss of load probability for the 18 W solar LED system is 14.1% in winter and zero in summer. For the 100 W solar LED system, the loss of load probability is 3.6% in spring. © 2009 Elsevier Ltd. All rights reserved.

  4. Connections beyond the margins of the power grid Information technology and the evolution of off-grid solar electricity in the developing world

    Science.gov (United States)

    Alstone, Peter Michael

    This work explores the intersections of information technology and off-grid electricity deployment in the developing world with focus on a key instance: the emergence of pay-as-you-go (PAYG) solar household-scale energy systems. It is grounded in detailed field study by my research team in Kenya between 2013-2014 that included primary data collection across the solar supply chain from global businesses through national and local distribution and to the end-users. We supplement the information with business process and national survey data to develop a detailed view of the markets, technology systems, and individuals who interact within those frameworks. The findings are presented in this dissertation as a series of four chapters with introductory, bridging, and synthesis material between them. The first chapter, Decentralized Energy Systems for Clean Electricity Access, presents a global view of the emerging off-grid power sector. Long-run trends in technology create "a unique moment in history" for closing the gap between global population and access to electricity, which has stubbornly held at 1-2 billion people without power since the initiation of the electric utility business model in the late 1800's. We show the potential for widespread near-term adoption of off-grid solar, which could lead to ten times less inequality in access and also ten times lower household-level climate impacts. Decentralized power systems that replace fuel-based incumbent lighting can advance the causes of climate stabilization, economic and social freedom and human health. Chapters two and three are focused on market and institutional dynamics present circa 2014 in for off-grid solar with a focus on the Kenya market. Chapter 2, "Off-grid Power and Connectivity", presents our findings related to the widespread influence of information technology across the supply chain for solar and in PAYG approaches. Using digital financing and embedded payment verification technology, PAYG

  5. LED based lightsource for replacement of neon tubes; LED baseret lyskilde til erstatning af lysstofroer

    Energy Technology Data Exchange (ETDEWEB)

    Krogh Jensen, A.

    2005-01-01

    During this project two generations of prototypes of a new type of fluorescent tube that uses light diodes. The technology is expected to result in an electricity consumption reduction of 75 % and a five times longer service life than conventional fluorescent tubes. (BA)

  6. New insights into bacterial adaptation through in vivo and in silico experimental evolution.

    Science.gov (United States)

    Hindré, Thomas; Knibbe, Carole; Beslon, Guillaume; Schneider, Dominique

    2012-03-27

    Microbiology research has recently undergone major developments that have led to great progress towards obtaining an integrated view of microbial cell function. Microbial genetics, high-throughput technologies and systems biology have all provided an improved understanding of the structure and function of bacterial genomes and cellular networks. However, integrated evolutionary perspectives are needed to relate the dynamics of adaptive changes to the phenotypic and genotypic landscapes of living organisms. Here, we review evolution experiments, carried out both in vivo with microorganisms and in silico with artificial organisms, that have provided insights into bacterial adaptation and emphasize the potential of bacterial regulatory networks to evolve.

  7. Carrier Lifetimes in Fluorescent 6H-SiC for LEDs Application

    DEFF Research Database (Denmark)

    Grivickas, Vytautas; Gulbinas, Karolis; Jokubavičius, Valdas

    Recently it was shown a new approach based on all-semiconductor material technology which is composed with a near ultra-violet GaN LED excitation source and fluorescent silicon carbide (f-6H-SiC) substrate which generates a visible broad spectral light by N and B dopants and an efficient donor...... to acceptor pair recombination [1,2]. This combination can achieve higher electric-light conversion efficiency and high color rendering in comparison with today’s used blue GaN LED based and phosphors. The devices are promising candidates for general lightning applications and may obtain stability....../reproducibility, and potentially low cost in high performance LEDs. However, there are still many problems to obtain best optimization for f-6H-SiC material since neither carrier transport, nor the carrier recombination is known in such co-doped carbides. From the existing data of carrier lifetimes in the SiC materials...

  8. Epitaxial Growth of GaN-based LEDs on Simple Sacrificial Substrates

    Energy Technology Data Exchange (ETDEWEB)

    Ian Ferguson; Chris Summers

    2009-12-31

    The objective of this project is to produce alternative substrate technologies for GaN-based LEDs by developing an ALD interlayer of Al{sub 2}O{sub 3} on sacrificial substrates such as ZnO and Si. A sacrificial substrate is used for device growth that can easily be removed using a wet chemical etchant leaving only the thin GaN epi-layer. After substrate removal, the GaN LED chip can then be mounted in several different ways to a metal heat sink/reflector and light extraction techniques can then be applied to the chip and compared for performance. Success in this work will lead to high efficiency LED devices with a simple low cost fabrication method and high product yield as stated by DOE goals for its solid state lighting portfolio.

  9. Degradation and corresponding failure mechanism for GaN-based LEDs

    Science.gov (United States)

    Fu, Jiajia; Zhao, Lixia; Cao, Haicheng; Sun, Xuejiao; Sun, Baojuan; Wang, Junxi; Li, Jinmin

    2016-05-01

    The degradation behaviors of high power GaN-based vertical blue LEDs on Si substrates were measured using in-situ accelerated life test. The results show that the dominant failure mechanism would be different during the operation. Besides that, the corresponding associated failure mechanisms were investigated systematically by using different analysis technologies, such as Scan Electron Microscopy, Reflectivity spectroscopy, Transient Thermal Analysis, Raman Spectra, etc. It is shown that initially, the failure modes were mainly originated from the semiconductor die and interconnect, while afterwards, the following serious deterioration of the radiant fluxes was attributed to the package. The interface material and quality, such as die attach and frame, play an important role in determining the thermal performance and reliability. In addition, the heating effect during the operation will also release the compressive strain in the chip. These findings will help to improve the reliability of GaN-based LEDs, especially for the LEDs with vertical structure.

  10. 'No blue' LED solution for photolithography room illumination

    DEFF Research Database (Denmark)

    Ou, Haiyan; Corell, Dennis Dan; Dam-Hansen, Carsten

    2010-01-01

    This paper explored the feasibility of using a LED-based bulb as the illumination light source for photolithography room. A no-blue LED was designed, and the prototype was fabricated. The spectral power distribution of both the LED bulb and the yellow fluorescent tube was measured. Based on that......, colorimetric values were calculated and compared on terms of chromatic coordinates, correlated color temperature, color rendering index, and chromatic deviation. Gretagmacbeth color charts were used as a more visional way to compare the two light sources, which shows that our no-blue LED bulb has much better...... color rendering ability than the YFT. Furthermore, LED solution has design flexibility to improve it further. The prototype has been tested with photoresist SU8-2005. Even after 15 days of illumination, no effect was observed. So this LED-based solution was demonstrated to be a very promising light...

  11. UV LED lithography with digitally tunable exposure dose

    Science.gov (United States)

    Yapici, Murat Kaya; Farhat, Ilyas

    2014-10-01

    This paper reports the development of a low-cost, portable, light-emitting diode (LED)-based ultraviolet (UV) exposure system. The major system components include UV-LEDs, a microcontroller, a digital-to-analog converter, and LED control circuitry. Through its front panel with a liquid crystal display and keypad, the UV-LED lithography system is able to receive user-defined values for exposure time and power, which allows the exposure dose to be tunable on demand. Compared to standard mask aligners, the UV-LED lithography system is a fraction of the cost, is simpler to construct using off-the shelf components, and does not require a complex infrastructure to operate. Such a reduction in system cost and complexity renders UV-LED lithography a perfect candidate for microlithography with large process windows typically suitable for MEMS, microfluidics applications.

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

    Science.gov (United States)

    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.

  13. Evolution of science I: Evolution of Mind

    CERN Document Server

    Vahia, M N

    2016-01-01

    The central nervous system and particularly the brain was designed to control the life cycle of a living being. With increasing size and sophistication, in mammals, the brain became capable of exercising significant control over life. In Homo Sapiens the brain became significantly powerful and capable of comprehension beyond survival needs with visualisation, formal thought and long term memory. Here we trace the rise of the powers of the brains of the Homo Sapiens and its capability of three comprehending the three spatial dimensions as well as time. By tracing the evolution of technology over the last millennium and particularly the late arrival of astronomy to discuss the evolution of the formal thinking process in humans. In a follow up paper we will trace the extensive use of this new faculty by humans to comprehend the working of the universe.

  14. Ethics, evolution and culture.

    Science.gov (United States)

    Mesoudi, Alex; Danielson, Peter

    2008-08-01

    Recent work in the fields of evolutionary ethics and moral psychology appears to be converging on a single empirically- and evolutionary-based science of morality or ethics. To date, however, these fields have failed to provide an adequate conceptualisation of how culture affects the content and distribution of moral norms. This is particularly important for a large class of moral norms relating to rapidly changing technological or social environments, such as norms regarding the acceptability of genetically modified organisms. Here we suggest that a science of morality/ethics can benefit from adopting a cultural evolution or gene-culture coevolution approach, which treats culture as a second, separate evolutionary system that acts in parallel to biological/genetic evolution. This cultural evolution approach brings with it a set of established theoretical concepts (e.g. different cultural transmission mechanisms) and empirical methods (e.g. evolutionary game theory) that can significantly improve our understanding of human morality.

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

    Energy Technology Data Exchange (ETDEWEB)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    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

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

    Science.gov (United States)

    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.

  18. Effect of LED lamping on the chlorophylls of leaf mustard

    Science.gov (United States)

    Wu, Shiqiang; Zhu, Liang; Zhao, Fuli; Yang, Bowen; Chen, Zuxin; Cai, Ruhai; Chen, Jiansheng

    The absorption coefficients of chloroplast of leaf mustard were measured by a spectrophotometer. The leaves were collected from seven treatments with different lighting. The chlorophyll content was calculated following Arnon equation. LEDs for filling the light source can increase the conduction of plants. Compared with other treatments, Chlorophyll in the leaves got an higher concentration under the lamping of red LEDS to blue LEDS for 7:1 .

  19. Recent results on the degradation of white LEDs for lighting

    OpenAIRE

    Meneghesso, G.; Meneghini, M.; Zanoni, E.

    2010-01-01

    Abstract Over the last years, GaN-based LEDs have shown to be excellent candidates for the realization of highefficiency light sources. White LEDs based on phosphor conversion can reach record efficiencies in excess of 150 lm/W, as demonstrated by several manufacturers and research groups. However, the reliability of white LEDs is still limited by a number of issuesthat must be addressed before these devices can find wide application in the market. This paper gives an overview on the most ...

  20. Management of Subarachnoid Hemorrhage in Two Important Italian Political Leaders: A Paradigm of Ethical and Technological Evolution of Neurosurgery During the Past Half-Century.

    Science.gov (United States)

    Longatti, Pierluigi; Giombelli, Ermanno; Pavesi, Giacomo; Carteri, Alessandro; Feletti, Alberto

    2016-08-01

    For a curious and extraordinary coincidence, 5 of the 7 most relevant leaders of the Italian Communist Party (Partito Comunista Italiano, which was established in 1921, has been the biggest Communist Party in Western Countries) suffered a cerebral stroke. Cerebrovascular diseases afflicted also Stalin and Lenin, and a number of Presidents of the United States. We present the stories of 2 important Italian political leaders who shared both the leadership role of the major left Italian Party and the dramatic experience of a subarachnoid hemorrhage. Retracing their medical incidents, separated by 50 years of history, we show how a fatal medical disease has become neurosurgical and successfully cured thanks to the advances of neurosurgery, neuroradiology, and hospital organization. A neurologic disease that was disgraceful 50 years ago has lost any disquieting and embarrassing significance in the present time to the light of evolution of vascular neurosurgery.