WorldWideScience

Sample records for cd-free cigs based

  1. Chemical deposition methods for Cd-free buffer layers in CI(G)S solar cells: Role of window layers

    International Nuclear Information System (INIS)

    It is currently possible to prepare Cd-free Cu(In,Ga)Se2-based solar cells with efficiencies similar or higher than their CdS references. In these cells, higher efficiencies are generally obtained from soft chemical-based techniques giving conformal depositions such as chemical bath deposition (CBD), ion layer gas reaction (ILGAR) or atomic layer deposition (ALD). However most of these devices are characterized by their pronounced transient behaviour. The aim of this paper is to compare these different chemical-based methods (CBD, ALD, ILGAR...) and to try to provide evidence for the dominant influence of the interface between the Cd-free buffer layer and the window layer on the performance and on the metastable electronic behaviour of these solar cells.

  2. Design, development and manufacture of high-efficiency low-cost solar modules based on CIGS PVICs

    Science.gov (United States)

    Eldada, Louay

    2010-02-01

    We describe the design, development and manufacture of solar power panels based on photovoltaic integrated circuits (PVICs) with high-quality high-uniformity Copper Indium Gallium Selenide (CIGS) thin films produced with the unique combination of low-cost ink-based and physical vapor deposition (PVD) based nanoengineered precursor thin films and a reactive transfer printing method. Reactive transfer is a two-stage process relying on chemical reaction between two separate precursor films to form CIGS, one deposited on the substrate and the other on a printing plate in the first stage. In the second stage, these precursors are brought into intimate contact and rapidly reacted under pressure in the presence of an electrostatic field while heat is applied. The use of two independent thin films provides the benefits of independent composition and flexible deposition technique optimization, and eliminates pre-reaction prior to the synthesis of CIGS. High quality CIGS with large grains on the order of several microns, and of preferred crystallographic orientation, are formed in just several minutes based on compositional and structural analysis by XRF, SIMS, SEM and XRD. Cell efficiencies of 14% and module efficiencies of 12% have been achieved using this method. When atmospheric pressure deposition of inks is utilized for the precursor films, the approach additionally provides lower energy consumption, higher throughput, and further reduced capital equipment cost with higher uptime.

  3. All-Nonvacuum-Processed CIGS Solar Cells Using Scalable Ag NWs/AZO-Based Transparent Electrodes.

    Science.gov (United States)

    Wang, Mingqing; Choy, Kwang-Leong

    2016-07-01

    With record cell efficiency of 21.7%, CIGS solar cells have demonstrated to be a very promising photovoltaic (PV) technology. However, their market penetration has been limited due to the inherent high cost of the cells. In this work, to lower the cost of CIGS solar cells, all nonvacuum-processed CIGS solar cells were designed and developed. CIGS absorber was prepared by the annealing of electrodeposited metallic layers in a chalcogen atmosphere. Nonvacuum-deposited Ag nanowires (NWs)/AZO transparent electrodes (TEs) with good transmittance (92.0% at 550 nm) and high conductivity (sheet resistance of 20 Ω/□) were used to replace the vacuum-sputtered window layer. Additional thermal treatment after device preparation was conducted at 220 °C for a few of minutes to improve both the value and the uniformity of the efficiency of CIGS pixel cell on 5 × 5 cm substrate. The best performance of the all-nonvacuum-fabricated CIGS solar cells showed an efficiency of 14.05% with Jsc of 34.82 mA/cm(2), Voc of 0.58 V, and FF of 69.60%, respectively, which is comparable with the efficiency of 14.45% of a reference cell using a sputtered window layer. PMID:27299854

  4. Trajectory-Oriented and Fault-Tolerant-Based Intelligent Process Control for Flexible CIGS PV Module Manufacturing; Final Technical Report, 13 May 2002--30 May 2005

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, L.; Britt, J.; Birkmire, R.; Vincent, T.

    2005-10-01

    ITN Energy Systems, Inc., and Global Solar Energy, Inc., assisted by NREL's PV Manufacturing R&D program, have continued to advance CIGS production technology by developing trajectory-oriented predictive/control models, fault-tolerance control, control platform development, in-situ sensors, and process improvements. Modeling activities included developing physics-based and empirical models for CIGS and sputter-deposition processing, implementing model-based control, and applying predictive models to the construction of new evaporation sources and for control. Model-based control is enabled by implementing reduced or empirical models into a control platform. Reliability improvement activities include implementing preventive maintenance schedules; detecting failed sensors/equipment and reconfiguring to tinue processing; and systematic development of fault prevention and reconfiguration strategies for the full range of CIGS PV production deposition processes. In-situ sensor development activities have resulted in improved control and indicated the potential for enhanced process status monitoring and control of the deposition processes. Substantial process improvements have been made, including significant improvement in CIGS uniformity, thickness control, efficiency, yield, and throughput. In large measure, these gains have been driven by process optimization, which in turn have been enabled by control and reliability improvements due to this PV Manufacturing R&D program.

  5. Analysis on the Performance of Copper Indium Gallium Selenide (CIGS Based Photovoltaic Thermal

    Directory of Open Access Journals (Sweden)

    Zulkepli Afzam

    2016-01-01

    Full Text Available This paper deals with the efficiency improvement of Copper Indium Gallium Selenide (CIGS Photovoltaic (PV and also solar thermal collector. Photovoltaic thermal (PV/T can improve overall efficiency for PV and also solve the problem of limited roof space at urban area. Objective of this study is to clarify the effect of mass flow rate on the efficiency of the PV/T system. A CIGS solar cell is used with rated output power 65 W and 1.18 m2 of area. 4 set of experiments were carried out, which were: thermal collector with 0.12 kg/s flow rate, PV/T with 0.12 kg/s flow rate, PV/T with 0.09 kg/s flow rate and PV. It was found that PV/T with 0.12 kg/s flow rate had the highest electrical efficiency, 2.92 %. PV/T with 0.09 kg/s flow rate had the lowest electrical efficiency, 2.68 %. It also had 2 % higher overall efficiency. The efficiency gained is low due to several factors. The rated output power of the PV is low for the area of 1.18 m2. The packing factor of the PV also need to be considered as it may not be operated at the optimal packing factor. Furthermore, aluminium sheet of the PV may affect the PV temperature due to high thermal conductivity. Further study on more values of mass flow rate and also other parameters that affect the efficiency of the PV/T is necessary.

  6. Noise properties of Pb/Cd-free thick film resistors

    Science.gov (United States)

    Witold Stadler, Adam; Kolek, Andrzej; Zawiślak, Zbigniew; Mleczko, Krzysztof; Jakubowska, Małgorzata; Rafał Kiełbasiński, Konrad; Młożniak, Anna

    2010-07-01

    Low-frequency noise spectroscopy has been used to examine noise properties of Pb/Cd-free RuO2- and CaRuO3-based thick films screen printed on alumina substrates. Experiments were performed in the temperature range 77-300 K and the frequency range 0.5-5000 Hz with multiterminal devices. The measured noise has been recognized as resistance noise that consists of background 1/f noise and components generated by several thermally activated noise sources (TANSs) of different activation energies. The total noise has been composed of the contributions generated in the resistive layer and in the resistive/conductive layers interface. These noise sources are non-uniformly distributed in the resistor volume. Noise intensity of new-resistive layers has been described by the noise parameter Cbulk. Pb/Cd-free layers turned out to be noisier than their Pb-containing counterparts; however, the removal of Pb and Cd from resistive composition is hardly responsible for the increase in the noise. In the case of RuO2 layers noise increases most likely due to larger grain size of RuO2 powder used to prepare resistive pastes. Information on the quality of the resistive-to-conductive layers interface occurred to be stored in the values of noise parameter Cint. Pb/Cd-free RuO2-based resistive pastes form well-behaved interfaces with various Ag-based conductive pastes. In contrast, CaRuO3-based paste forms bad contacts with AgPd terminations because the density of TANSs increases in the interface area.

  7. Noise properties of Pb/Cd-free thick film resistors

    International Nuclear Information System (INIS)

    Low-frequency noise spectroscopy has been used to examine noise properties of Pb/Cd-free RuO2- and CaRuO3-based thick films screen printed on alumina substrates. Experiments were performed in the temperature range 77-300 K and the frequency range 0.5-5000 Hz with multiterminal devices. The measured noise has been recognized as resistance noise that consists of background 1/f noise and components generated by several thermally activated noise sources (TANSs) of different activation energies. The total noise has been composed of the contributions generated in the resistive layer and in the resistive/conductive layers interface. These noise sources are non-uniformly distributed in the resistor volume. Noise intensity of new-resistive layers has been described by the noise parameter Cbulk. Pb/Cd-free layers turned out to be noisier than their Pb-containing counterparts; however, the removal of Pb and Cd from resistive composition is hardly responsible for the increase in the noise. In the case of RuO2 layers noise increases most likely due to larger grain size of RuO2 powder used to prepare resistive pastes. Information on the quality of the resistive-to-conductive layers interface occurred to be stored in the values of noise parameter Cint. Pb/Cd-free RuO2-based resistive pastes form well-behaved interfaces with various Ag-based conductive pastes. In contrast, CaRuO3-based paste forms bad contacts with AgPd terminations because the density of TANSs increases in the interface area.

  8. Thin film solar cells based on CdTe and Cu(In,Ga)Se{sub 2} (CIGS) compounds

    Energy Technology Data Exchange (ETDEWEB)

    Gladyshev, P P [International University of Nature, Society and Man ' Dubna' , Dubna (Russian Federation); Filin, S V; Puzynin, A I; Tanachev, I A; Rybakova, A V; Tuzova, V V; Kozlovskiy, S A [Center of High Technologies of FSUE ' Applied Acoustics Research Institute' , Dubna (Russian Federation); Gremenok, V F; Mudryi, A V; Zaretskaya, E P [State Scientific and Production Association ' Scientific-Practical Materials, Researcher Center of National Academy of Sciences of Belarus' , Minsk (Belarus); Zalesskiy, V B; Kravchenko, V M; Leonova, U R; Khodin, A A; Pilipovich, V A; Polikanin, A M [Institute of Physics of National Academy of Sciences of Belarus, Minsk (Belarus); Khrypunov, G S; Chernyh, E P; Kovtun, N A [National Technical University ' Kharkov Politechnical Institute' , Kharkov (Ukraine); Belonogov, E K, E-mail: pavel.gladyshev@niipa.ru [Voronej State Technical University, Voronej (Russian Federation)

    2011-04-01

    We are publishing recent results in chalcogenide photoelectric convertors fabrication, which are efforts of many scientific teams from Russia, Belarus, Ukraine, and Kazakhstan. Competitively high efficiency of photoelectric convertors (11.4% for CdTe and 11% for CIGS) was achieved in the process of our work. Furthermore, luminescent filters for improvement of spectral response of such chalcogenide solar cells in a short wavelengths region were also developed and investigated here.

  9. Structure and properties of CIGS films based on one-stage RF-sputtering process at low substrate temperature

    Institute of Scientific and Technical Information of China (English)

    Yong Yan; Shasha Li; Yufeng Ou; Yaxin Ji; Chuanpeng Yan; Lian Liu; Zhou Yu; Yong Zhao

    2014-01-01

    Currently, Nanjing South Railway Station planning to implement slate roof renovation is integrating solar cell modules into traditional roof materials to gen-erate clean energy. Copper-indium-gallium diselenide (CuIn1-xGaxSe2, CIGS) is one of the most promising materials for thin film solar cells. Cu(In1-xGax)Se2 films were deposited by a one-step radio frequency magnetron sputtering process at low substrate temperature. X-ray diffraction, Raman, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and electrical and optical measurements were carried out to investigate the deposited films. The results reveal that a temperature of 320 ?C is critical for near-stoichiometric CIGS films with uniform surface morphology. Cu-rich phase particulates are found at less than this temperature. The sample deposited at 380 ?C gives well-crystalline single-phase CIGS film. Furthermore, the electrical and optical performances of the absorber layer are improved significantly with the increasing substrate temperature.

  10. Experimental evidence of light soaking effect in Cd-free Cu{sub 2}ZnSn(S,Se){sub 4}-based solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Grenet, Louis, E-mail: louis.grenet@cea.fr [CEA, LITEN, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France); Grondin, Pauline; Coumert, Karol; Karst, Nicolas; Emieux, Fabrice; Roux, Frédéric; Fillon, Raphaël [CEA, LITEN, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France); Altamura, Giovanni [CEA-CNRS, UJF Group Nanophysique et semi-conducteurs, 38054 Grenoble Cedex 9 (France); Fournier, Hélène; Faucherand, Pascal; Perraud, Simon [CEA, LITEN, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France)

    2014-08-01

    The use of a Zn-based buffer layer for kesterite solar cells presents the double advantage of avoiding cadmium and reducing the amount of light absorbed in this layer. Cu{sub 2}ZnSn(S,Se){sub 4} solar cells with a ZnS(O,OH) buffer layer have been fabricated and power conversion efficiencies up to 5.8% after light soaking treatment have been measured. Cu{sub 2}ZnSn(Se,S){sub 4} solar cells with a CdS buffer layer have also been realized, leading to a power conversion efficiency up to 7.0%. The dynamics of the light soaking effect in the case of the ZnS(O,OH) buffer layer has been studied as well, and compared to the same effect on a cell with a Cu(In,Ga)Se{sub 2} absorber layer. - Highlights: • 5.8% of efficiency for a Cu{sub 2}ZnSn(S,Se){sub 4} solar cell with a ZnS(O,OH) buffer layer • 7.0% of efficiency for a reference Cu{sub 2}ZnSn(S,Se){sub 4} solar cell with a CdS buffer layer • ZnS(O,OH) buffer layer required at least 1000 min of light soaking treatment. • Required light soaking treatment is longer for Cu{sub 2}ZnSn(S,Se){sub 4} than for Cu(In,Ga)Se{sub 2}.

  11. Experimental evidence of light soaking effect in Cd-free Cu2ZnSn(S,Se)4-based solar cells

    International Nuclear Information System (INIS)

    The use of a Zn-based buffer layer for kesterite solar cells presents the double advantage of avoiding cadmium and reducing the amount of light absorbed in this layer. Cu2ZnSn(S,Se)4 solar cells with a ZnS(O,OH) buffer layer have been fabricated and power conversion efficiencies up to 5.8% after light soaking treatment have been measured. Cu2ZnSn(Se,S)4 solar cells with a CdS buffer layer have also been realized, leading to a power conversion efficiency up to 7.0%. The dynamics of the light soaking effect in the case of the ZnS(O,OH) buffer layer has been studied as well, and compared to the same effect on a cell with a Cu(In,Ga)Se2 absorber layer. - Highlights: • 5.8% of efficiency for a Cu2ZnSn(S,Se)4 solar cell with a ZnS(O,OH) buffer layer • 7.0% of efficiency for a reference Cu2ZnSn(S,Se)4 solar cell with a CdS buffer layer • ZnS(O,OH) buffer layer required at least 1000 min of light soaking treatment. • Required light soaking treatment is longer for Cu2ZnSn(S,Se)4 than for Cu(In,Ga)Se2

  12. Process Development for CIGS-Based Thin-Film Photovoltaic Modules; Phase I Technical Report, 5 February 1998--4 February 1999

    Energy Technology Data Exchange (ETDEWEB)

    Britt, J., Wiedeman, S.; Wendt, R.; Albright, S.

    1999-09-13

    This report describes work performed by Global Solar Energy (GSE) under Phase I of this subcontract. GSE has initiated an extensive and systematic plan to accelerate the commercialization of thin-film photovoltaics (PV) on copper indium gallium diselenide (CIGS). GSE is developing the technology to deposit and monolithically integrate CIGS photovoltaics on a flexible substrate. CIGS-deposited on flexible substrates can be fabricated into either flexible or rigid modules. Low-cost, rigid PV panels for remote power, bulk/utility, telecommunications, and rooftop applications will be produced by affixing the flexible CIGS to an expensive rigid panel by lamination or adhesive. In the GSE approach, long (up to 700 m) continuous rolls of substrate are processed, as opposed to individual small glass plates. In combination with roll-to-roll processing, GSE is developing evaporation deposition operations that enable low-cost and high-efficiency CIGS modules. Efforts are under way to transition the CIGS deposition process into manufacturing at GSE. CIGS process development is focused on synchronizing the operation of the effusion sources, the Se delivery profile, substrate temperature, and a host of other parameters. GSE has selected an interconnect scheme and procured, installed, and tested the equipment necessary to implement the cell interconnection for thin-film CIGS modules on a polyimide substrate.

  13. Commercialization of High Efficiency Low Cost CIGS Technology Based on Electroplating: Final Technical Progress Report, 28 September 2007 - 30 June 2009

    Energy Technology Data Exchange (ETDEWEB)

    Basol, B.

    2010-08-01

    This report describes SoloPower's work as a Photovoltaic Technology Incubator awardee within the U.S. Department of Energy's Solar Energy Technologies Program. The term of this subcontract with the National Renewable Energy Laboratory was two years. The project focused on SoloPower's electrodeposition-based copper indium gallium (di)selenide (CIGS) technology. Under this subcontract, SoloPower improved the quality of its flexible metal substrates, increased the size of its solar cells from 0.5 cm2 to 120 cm2, increased the small-area cell efficiencies from near 11% to near 14%, demonstrated large-area cells, and developed a module manufacturing process.

  14. Physics-Based Compact Model for CIGS and CdTe Solar Cells: From Voltage-Dependent Carrier Collection to Light-Enhanced Reverse Breakdown: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Xingshu; Alam, Muhammad Ashraful; Raguse, John; Garris, Rebekah; Deline, Chris; Silverman, Timothy

    2015-10-15

    In this paper, we develop a physics-based compact model for copper indium gallium diselenide (CIGS) and cadmium telluride (CdTe) heterojunction solar cells that attributes the failure of superposition to voltage-dependent carrier collection in the absorber layer, and interprets light-enhanced reverse breakdown as a consequence of tunneling-assisted Poole-Frenkel conduction. The temperature dependence of the model is validated against both simulation and experimental data for the entire range of bias conditions. The model can be used to characterize device parameters, optimize new designs, and most importantly, predict performance and reliability of solar panels including the effects of self-heating and reverse breakdown due to partial-shading degradation.

  15. Cost and Reliability Improvement for CIGS-Based PV on Flexible Substrate: May 24, 2006 -- July 31, 2010

    Energy Technology Data Exchange (ETDEWEB)

    Wiedeman, S.

    2011-05-01

    Global Solar Energy rapidly advances the cost and performance of commercial thin-film CIGS products using roll-to-roll processing on steel foil substrate in compact, low cost deposition equipment, with in-situ sensors for real-time intelligent process control. Substantial increases in power module efficiency, which now exceed 13%, are evident at GSE factories in two countries with a combined capacity greater than 75 MW. During 2009 the average efficiency of cell strings (3780 cm2) was increased from 7% to over 11%, with champion results exceeding 13% Continued testing of module reliability in rigid product has reaffirmed extended life expectancy for standard glass product, and has qualified additional lower-cost methods and materials. Expected lifetime for PV in flexible packages continues to increase as failure mechanisms are elucidated, and resolved by better methods and materials. Cost reduction has been achieved through better materials utilization, enhanced vendor and material qualification and selection. The largest cost gains have come as a result of higher cell conversion efficiency and yields, higher processing rates, greater automation and improved control in all process steps. These improvements are integral to this thin film PV partnership program, and all realized with the 'Gen2' manufacturing plants, processes and equipment.

  16. Degradation of CIGS solar cells

    NARCIS (Netherlands)

    Theelen, M.J.

    2015-01-01

    Thin film CIGS solar cells and individual layers within these solar cells have been tested in order to assess their long term stability. Alongside with the execution of standard tests, in which elevated temperatures and humidity levels are used, the solar cells have also been exposed to a combinatio

  17. A study on the optics of copper indium gallium (di)selenide (CIGS) solar cells with ultra-thin absorber layers

    NARCIS (Netherlands)

    Xu, M.; Wachters, A.J.H.; Deelen, J. van; Mourad, M.C.D.; Buskens, P.J.P.

    2014-01-01

    We present a systematic study of the effect of variation of the zinc oxide (ZnO) and copper indium gallium (di)selenide (CIGS) layer thickness on the absorption characteristics of CIGS solar cells using a simulation program based on finite element method (FEM). We show that the absorption in the CIG

  18. CIGS Thin Film Solar Cells, phase 2 Uppsala University Final report 2006-01-01 - 2007-06-14

    Energy Technology Data Exchange (ETDEWEB)

    Edoff, Marika (Thin Film Solar Cell group, Dep. Technical Sciences, Uppsala Univ., P.O. Box 534, SE-751 21 Uppsala (Sweden)) (and others)

    2007-06-15

    The project CIGS Thin Film Solar Cells, phase 2 has been going on for 18,5 months and was interrupted in advance on the 14th of June, 2007. The decision to shorten the period was taken by the board of the Swedish Energy Agency the 14th of February. It was decided to reevaluate and re-direct the financial support to the group. A new project, CIGS Thin Film Solar Cells, phase 3, superseded this project and will go on for the initially planned project period (until 2009-12-31). During the project much of the focus has been on research on Cd-free buffer layers, with an emphasis on the interface properties between the CIGS and the buffer layer. (CIGS is a commonly used acronym for Cu(In,Ga)Se{sub 2}, which is the active absorption layer in this type of solar cells) The combination of high quality CIGS and the new buffer layers has been another field of interest. CIGS solar cell module development and computer modelling of solar cells and modules has been the third major research area. The results show that the group still holds a position as one of the leaders in the world in this field. The 18.5 % efficient Cd-free solar cell, which was obtained and independently confirmed is only one percent away from the world record and in addition it is Cd-free using a Zn(O,S) buffer layer (the world record from NREL contains Cd). By alloying ZnO with MgO instead of ZnS almost equally good results can be achieved. During the last half year an 18.1 % cell has been measured with a (Zn,Mg)O buffer layer. Solar cell module technology includes several research issues, both fundamental as e.g. modelling of cell voltage and losses as a function of distance from interconnect to interconnect, but also more development as e.g. encapsulation routines. The harsh environment test (damp heat test) run at 85 deg C and 85 % relative humidity for 1000 hours was passed for both a small (12.5x12.5 cm2) and a large (27.5x30 cm2) module within the degradation limits stated by the IEC standards, using

  19. Monolithic DSSC/CIGS tandem solar cell fabricated by a solution process

    OpenAIRE

    Moon, Sung Hwan; Park, Se Jin; Kim, Sang Hoon; Lee, Min Woo; Han, Jisu; Kim, Jin Young; Kim, Honggon; Hwang, Yun Jeong; Lee, Doh-Kwon; Min, Byoung Koun

    2015-01-01

    Tandem architecture between organic (dye-sensitized solar cell, DSSC) and inorganic (CuInGaSe2 thin film solar cell, CIGS) single-junction solar cells was constructed particularly based on a solution process. Arc-plasma deposition was employed for the Pt interfacial layer to minimize the damage to the layers of the CIGS bottom cell. Solar cell efficiency of 13% was achieved, which is significant progress from individual single-junction solar cells (e.g., 7.25 and 6.2% for DSSC and CIGS, respe...

  20. Thin-Film CIGS Photovoltaic Technology: Annual Technical Report-Phase II, 16 April 1999-15 April 2000

    Energy Technology Data Exchange (ETDEWEB)

    Delahoy, A.E.; Bruns, J.; Ruppert, A.; Akhtar, M.; Chen, L.; Kiss, Z.J.

    2000-08-24

    A summary of Energy Photovoltaics' Phase II work includes the following: (1) EPV has demonstrated that it can sputter a Mo back-contact capable of supporting very high efficiency cell processing. Using EPV Mo, NREL has deposited a 17.1% CIGS cell (no AR coating). EPV believes it can identify the signature of ``good'' Mo. The Mo was produced on EPV's 0.43 m{sup 2} pilot-line equipment; (2) EPV has performed compound synthesis for several classes of materials, namely non-Cu precursor materials, Cu-containing materials, and ternary buffer materials. Using a ternary compound synthesized at EPV (ZIS) as an evaporation source material for the buffer layer, a Cd-free CIGS device has been produced having an efficiency of 11.5% (560 mV, 32.1 mA/cm{sup 2}, FF 64.3%). The ZIS films are photoconductive, and the devices exhibit no dark-light crossover or light soaking effects; (3) EPV initiated the interest of the University of Oregon in capacitance spectroscopy of CIGS devices. An Urbach tail with characteristic energy E0 < 20meV was identified by transient photocapacitance spectroscopy; (4) Small-area CIGS devices were produced in the pilot-line system with an efficiency of 12.0% (581 mV, 30.1 mA/cm{sup 2}, FF 68.7%), and in an R and D-scale system with 13.3% efficiency (569 mV, 34.1 mA/cm{sup 2}, FF 68.1%); (5) An improved linear evaporation source for Cu delivery has been developed and was used for CIGS formation in the pilot-line system. The deposition width is 45 cm. This technological ``tour de force'' allows EPV to build large-area CIGS systems possessing considerable flexibility. In particular, both EPV's FORNAX process and NREL's 3-stage process have been implemented on the pilot line. A CIGS thickness uniformity of 7% over a 40 cm width has been achieved; (6) A 4-head linear source assembly was designed, constructed, and is in use. Flux monitoring is practiced; (7) Large-area CIGS modules were produced with Voc's up to 36

  1. Use of different Zn precursors for the deposition of Zn(S,O) buffer layers by chemical bath for chalcopyrite based Cd-free thin-film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Saez-Araoz, R.; Lux-Steiner, M.C. [Hahn Meitner Institut, Berlin (Germany); Freie Universitaet Berlin, Berlin (Germany); Ennaoui, A.; Kropp, T.; Veryaeva, E. [Hahn Meitner Institut, Berlin (Germany); Niesen, T.P. [AVANCIS GmbH and Co. KG, Munich (Germany)

    2008-10-15

    Progress in fabricating Cu(In,Ga)(S,Se){sub 2} (CIGSSe) solar cells with Zn(S,O) buffer layers prepared by chemical bath deposition (CBD) is discussed. The effect of different Zn salt precursors on solar cell device performance is investigated using production scale CIGSSe absorbers provided by AVANCIS GmbH and Co. KG. The CBD process has been developed at the Hahn-Meitner-Institut (HMI) using zinc nitrate, zinc sulphate or zinc chloride as zinc precursor. An average efficiency of 14.2{+-}0.8% is obtained by using one-layer CBD Zn(S,O) The dominant recombination path for well performing solar cells is discussed based on the results obtained from temperature dependent J(V) analysis. The structure and morphology of buffer layers deposited using zinc nitrate and zinc sulphate has been studied by means of transmission electron micrographs of glass/Mo/CIGSSe/Zn(S,O) structures. Results show a conformal coverage of the absorber by a Zn(S,O) layer of 15-25 nm consisting of nanocrystals with radii of {proportional_to}5 nm. XAES analysis of the buffer layer reveals a similar surface composition for buffer layers deposited with zinc nitrate and zinc sulphate. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  2. Graded Carrier Concentration Absorber Profile for High Efficiency CIGS Solar Cells

    Directory of Open Access Journals (Sweden)

    Antonino Parisi

    2015-01-01

    Full Text Available We demonstrate an innovative CIGS-based solar cells model with a graded doping concentration absorber profile, capable of achieving high efficiency values. In detail, we start with an in-depth discussion concerning the parametrical study of conventional CIGS solar cells structures. We have used the wxAMPS software in order to numerically simulate cell electrical behaviour. By means of simulations, we have studied the variation of relevant physical and chemical parameters—characteristic of such devices—with changing energy gap and doping density of the absorber layer. Our results show that, in uniform CIGS cell, the efficiency, the open circuit voltage, and short circuit current heavily depend on CIGS band gap. Our numerical analysis highlights that the band gap value of 1.40 eV is optimal, but both the presence of Molybdenum back contact and the high carrier recombination near the junction noticeably reduce the crucial electrical parameters. For the above-mentioned reasons, we have demonstrated that the efficiency obtained by conventional CIGS cells is lower if compared to the values reached by our proposed graded carrier concentration profile structures (up to 21%.

  3. ZnMgO by APCVD Enabling High-Performance Mid-bandgap CIGS on Polyimide Modules: October 2009--October 2010

    Energy Technology Data Exchange (ETDEWEB)

    Woods, L.

    2011-04-01

    This Pre-Incubator project was designed to increase the 'real world' CIGS based photovoltaic module performance and decrease the Levelized Cost of Energy (LCOE) of systems utilizing those modules compared to our traditional CIGS based photovoltaic modules. This was enabled by a) increasing the CIGS bandgap and b) developing better matched device finishing layers to the mid-bandgap CIGS based photovoltaics; including window and buffer layers (and eventually the TCO). Incremental progress in the novel device performance was demonstrated throughout the program, and ultimately achieved performance results that exceeded the milestones ahead of schedule. Metal-oxide buffer layer devices with mid-bandgap CIGS alloys on polyimide substrates were produced with efficiencies of over 12%. Corresponding mid-bandgap devices with CdS buffers produced over 13% efficient devices. Furthermore, no obvious degradation in the device performance has been observed to date, after proper storage ambient of the different types of unencapsulated devices were identified.

  4. Improvement in efficiency of solar cell by removing Cu2-xSe from CIGS film surface

    Institute of Scientific and Technical Information of China (English)

    Li Wei; Sun Yun; Liu Wei; Li Feng-Yan; Zhou Lin

    2006-01-01

    CIGS thin films are deposited by sputtering and selenization.The synthesis of semiconducting polycrystalline thin films and characteristics of devices based on the CIGS absorbing layers are investigated.Their microstructures are characterized by X-ray diffraction and Raman spectroscopy.The results reveal that there exist metallic Cu2-xSe compounds in CIGS film surfaces and the compounds are thought to be responsible for the degradation of the open circuit voltage of solar cells.The optimization of selenization temperature profile and copper content in the precursor surfaces is studied,concluding that the conversion efficiency may be improved by removing metallic Cu2-xSe compounds from the surfaces of CIGS thin films.

  5. Simulation of CIGS Thin Film Solar Cells Using AMPS-1D

    Directory of Open Access Journals (Sweden)

    J.R. Ray

    2011-01-01

    Full Text Available The solar cell structure based on copper indium gallium diselenide (CIGS as the absorber layer, cadmium sulfide (CdS as a buffer layer un-doped (i and Aluminium (Al doped zinc oxide (ZnO as a window layer was simulated using the one dimensional simulation program called analysis of microelectronic and photonic structures (AMPS-1D. In the simulation, the thickness of CIGS layer was varied from 300 to 3000 nm. The rest of layer’s thicknesses were kept constant, viz. 60 nm for CdS, and 80 nm and 500 nm for i- and Al-ZnO, respectively. By varying thickness of CIGS layer the simulated device performance was demonstrate in the form of current-voltage (I-V characteristics and quantum efficiency (QE.

  6. Solution-deposited CIGS thin films for ultra-low-cost photovoltaics

    Science.gov (United States)

    Eldada, Louay A.; Hersh, Peter; Stanbery, Billy J.

    2010-09-01

    We describe the production of photovoltaic modules with high-quality large-grain copper indium gallium selenide (CIGS) thin films obtained with the unique combination of low-cost ink-based precursors and a reactive transfer printing method. The proprietary metal-organic inks contain a variety of soluble Cu-, In- and Ga- multinary selenide materials; they are called metal-organic decomposition (MOD) precursors, as they are designed to decompose into the desired precursors. Reactive transfer is a two-stage process that produces CIGS through the chemical reaction between two separate precursor films, one deposited on the substrate and the other on a printing plate in the first stage. In the second stage, these precursors are rapidly reacted together under pressure in the presence of heat. The use of two independent thin films provides the benefits of independent composition and flexible deposition technique optimization, and eliminates pre-reaction prior to the synthesis of CIGS. In a few minutes, the process produces high quality CIGS films, with large grains on the order of several microns, and preferred crystallographic orientation, as confirmed by compositional and structural analysis by XRF, SIMS, SEM and XRD. Cell efficiencies of 14% and module efficiencies of 12% were achieved using this method. The atmospheric deposition processes include slot die extrusion coating, ultrasonic atomization spraying, pneumatic atomization spraying, inkjet printing, direct writing, and screen printing, and provide low capital equipment cost, low thermal budget, and high throughput.

  7. 7 CFR 1466.27 - Conservation Innovation Grants (CIG).

    Science.gov (United States)

    2010-01-01

    ... PROGRAM Contracts and Payments § 1466.27 Conservation Innovation Grants (CIG). (a) Definitions. In addition to the terms defined in § 1466.3 of this part, the following definitions shall be applicable to... 7 Agriculture 10 2010-01-01 2010-01-01 false Conservation Innovation Grants (CIG). 1466.27...

  8. 2D - Finite element model of a CIGS module

    Energy Technology Data Exchange (ETDEWEB)

    Janssen, G.J.M.; Slooff, L.H.; Bende, E.E. [ECN Solar Energy, Petten (Netherlands)

    2012-09-15

    The performance of thin-film CIGS modules is often limited due to inhomogeneities in CIGS layers. A 2-dimensional Finite Element Model for CIGS modules is demonstrated that predicts the impact of such inhomogeneities on the module performance. Results are presented of a module with a region of poor diode characteristics. It is concluded that according to this model the effects of poor diodes depend strongly on their location in the module and on their dispersion over the module surface. Due to its generic character the model can also be applied to other series connections of photovoltaic cells.

  9. E-Cig Liquid Nicotine Containers Often Mislabeled

    Science.gov (United States)

    ... medlineplus.gov/news/fullstory_160108.html E-Cig Liquid Nicotine Containers Often Mislabeled Also, many aren't ... July 27, 2016 (HealthDay News) -- Containers that hold liquid nicotine for electronic cigarettes may not be labeled ...

  10. Are E-Cigs Slowing Teen Anti-Smoking Push?

    Science.gov (United States)

    ... https://medlineplus.gov/news/fullstory_159809.html Are E-Cigs Slowing Teen Anti-Smoking Push? Researchers blame ... a new study contends. "We found evidence that e-cigarettes are recruiting at least some youth who ...

  11. E-Cigs May Damage Cells in Mouth

    Science.gov (United States)

    ... 159657.html E-Cigs May Damage Cells in Mouth Findings suggest a possible increase in the risk ... The oral cavity is the portion of the mouth behind the teeth and gums. The researchers believe ...

  12. Highly stable tandem solar cell monolithically integrating dye-sensitized and CIGS solar cells

    Science.gov (United States)

    Chae, Sang Youn; Park, Se Jin; Joo, Oh-Shim; Jun, Yongseok; Min, Byoung Koun; Hwang, Yun Jeong

    2016-01-01

    A highly stable monolithic tandem solar cell was developed by combining the heterogeneous photovoltaic technologies of dye-sensitized solar cell (DSSC) and solution-processed CuInxGa1-xSeyS1-y (CIGS) thin film solar cells. The durability of the tandem cell was dramatically enhanced by replacing the redox couple from to [Co(bpy)3]2+ /[Co(bpy)3]3+), accompanied by a well-matched counter electrode (PEDOT:PSS) and sensitizer (Y123). A 1000 h durability test of the DSSC/CIGS tandem solar cell in ambient conditions resulted in only a 5% decrease in solar cell efficiency. Based on electrochemical impedance spectroscopy and photoelectrochemical cell measurement, the enhanced stability of the tandem cell is attributed to minimal corrosion by the cobalt-based polypyridine complex redox couple. PMID:27489138

  13. Optical Metrology for CIGS Solar Cell Manufacturing and its Cost Implications

    Science.gov (United States)

    Sunkoju, Sravan Kumar

    Solar energy is a promising source of renewable energy which can meet the demand for clean energy in near future with advances in research in the field of photovoltaics and cost reduction by commercialization. Availability of a non-contact, in-line, real time robust process control strategies can greatly aid in reducing the gap between cell and module efficiencies, thereby leading to cost-effective large-scale manufacturing of high efficiency CIGS solar cells. In order to achieve proper process monitoring and control for the deposition of the functional layers of CuIn1-xGaxSe 2 (CIGS) based thin film solar cell, optical techniques such as spectroscopic reflectometry and polarimetry are advantageous because they can be set up in an unobtrusive manner in the manufacturing line, and collect data in-line and in-situ. The use of these techniques requires accurate optical models that correctly represent the properties of the layers being deposited. In this study, Spectroscopic ellipsometry (SE) has been applied for the characterization of each individual stage of CIGS layers deposited using the 3-stage co-evaporation process along with the other functional layers. Dielectric functions have been determined for the energy range from 0.7 eV to 5.1 eV. Critical-point line-shape analysis was used in this study to determine the critical point energies of the CIGS based layers. To control the compositional and thickness uniformity of all the functional layers during the fabrication of CIGS solar cells over large areas, multilayer photovoltaics (PV) stack optical models were developed with the help of extracted dielectric functions. In this study, mapping capability of RC2 spectroscopic ellipsometer was used to map all the functional layer thicknesses of a CIGS solar cell in order to probe the spatial non-uniformities that can affect the performance of a cell. The optical functions for each of the stages of CIGS 3-stage deposition process along with buffer layer and transparent

  14. Characterizing the effects of silver alloying in chalcopyrite CIGS solar cells with junction capacitance methods

    Energy Technology Data Exchange (ETDEWEB)

    Erslev, Peter T.; Hanket, Gregory M.; Shafarman, William N.; Cohen, J. David

    2009-04-01

    A variety of junction capacitance-based characterization methods were used to investigate alloys of Ag into Cu(In1-xGax)Se2 photovoltaic solar cells over a broad range of compositions. These alloys show encouraging trends of increasing VOC with increasing Ag content, opening the possibility of wide-gap cells for use in tandem device applications. Drive level capacitance profiling (DLCP) has shown very low free carrier concentrations for all Ag-alloyed devices, in some cases less than 1014 cm-3, which is roughly an order of magnitude lower than that of CIGS devices. Transient photocapacitance spectroscopy has revealed very steep Urbach edges, with energies between 10 meV and 20 meV, in the Ag-alloyed samples. This is in general lower than the Urbach edges measured for standard CIGS samples and suggests a significantly lower degree of structural disorder.

  15. Device Modeling and Characterization for CIGS Solar Cells

    Science.gov (United States)

    Song, Sang Ho

    We studied the way to achieve high efficiency and low cost of CuIn1-xGaxSe2 (CIGS) solar cells. The Fowler-Nordheim (F-N) tunneling currents at low bias decreased the shunt resistances and degraded the fill factor and efficiency. The activation energies of majority traps were directly related with F-N tunneling currents by the energy barriers. Air anneals decreased the efficiency from 7.74% to 5.18% after a 150 °C, 1000 hour anneal. The decrease of shunt resistance due to F-N tunneling and the increase of series resistance degrade the efficiencies of solar cells. Air anneal reduces the free carrier densities by the newly generated Cu interstitial defects (Cui). Mobile Cui defects induce the metastability in CIGS solar cell. Since oxygen atoms are preferred to passivate the Se vacancies thus Cu interstitial defects explains well metastability of CIGS solar cells. Lattice mismatch and misfit stress between layers in CIGS solar cells can explain the particular effects of CIGS solar cells. The misfits of 35.08° rotated (220/204) CIGS to r-plane (102) MoSe2 layers are 1% ˜ -4% lower than other orientation and the lattice constants of two layers in short direction are matched at Ga composition x=0.35. This explains well the preferred orientation and the maximum efficiency of Ga composition effects. Misfit between CIGS and CdS generated the dislocations in CdS layer as the interface traps. Thermionic emission currents due to interface traps limit the open circuit voltage at high Ga composition. The trap densities were calculated by critical thickness and dislocation spacing and the numerical device simulation results were well matched with the experimental results. A metal oxide broken-gap p-n heterojunction is suggested for tunnel junction for multi-junction polycrystalline solar cells and we examined the characteristics of broken-gap tunnel junction by numerical simulation. Ballistic transport mechanism explains well I-V characteristics of broken-gap junction. P

  16. Lessons learned from NMSG-085 CIG Land Operation demonstration

    NARCIS (Netherlands)

    Gautreau, B.; Remmersmann, T.; Henderson, H.C.; Reus, N.M. de; Khimeche, L.; Pedersen, E.; Lillesoe, J.; Liberg, D.

    2013-01-01

    This paper presents the experience gained during demonstrations carried out between Denmark, France, Germany, the Netherlands and Spain under the umbrella of the NMSG-085 / CIG Land Operation group. The demonstration, also presented in this paper, focuses on command post exercise training. It highli

  17. Interaction of ultra-short laser pulses with CIGS and CZTSe thin films

    Science.gov (United States)

    Gečys, P.; Markauskas, E.; Dudutis, J.; Račiukaitis, G.

    2014-01-01

    The thin-film solar cell technologies based on complex quaternary chalcopyrite and kesterite materials are becoming more attractive due to their potential for low production costs and optimal spectral performance. As in all thin-film technologies, high efficiency of small cells might be maintained with the transition to larger areas when small segments are interconnected in series to reduce photocurrent and related ohmic losses in thin films. Interconnect formation is based on the three scribing steps, and the use of a laser is here crucial for performance of the device. We present our simulation and experimental results on the ablation process investigations in complex CuIn1- x Ga x Se2 (CIGS) and Cu2ZnSn(S,Se)4 (CZTSe) cell's films using ultra-short pulsed infrared (~1 μm) lasers which can be applied to the damage-free front-side scribing processes. Two types of processes were investigated—direct laser ablation of ZnO:Al/CIGS films with a variable pulse duration of a femtosecond laser and the laser-induced material removal with a picosecond laser in the ZnO:Al/CZTSe structure. It has been found that the pulse energy and the number of laser pulses have a significantly stronger effect on the ablation quality in ZnO:Al/CIGS thin films rather than the laser pulse duration. For the thin-film scribing applications, it is very important to carefully select the processing parameters and use of ultra-short femtosecond pulses does not have a significant advantage compared to picosecond laser pulses. Investigations with the ZnO:Al/CZTSe thin films showed that process of the absorber layer removal was triggered by a micro-explosive effect induced by high pressure of sublimated material due to a rapid temperature increase at the molybdenum-CZTSe interface.

  18. Modelling Defects Acceptors And Determination Of Electric Model From The Nyquist Plot And Bode In Thin Film CIGS

    Directory of Open Access Journals (Sweden)

    Demba Diallo

    2015-08-01

    Full Text Available Abstract The performance of the chalcopyrite material CuInGaSe2 CIGS used as an absorber layer in thin-film photovoltaic devices is significantly affected by the presence of native defects. Multivalent defects e.g. double acceptors or simple acceptor are important immaterial used in solar cell production in general and in chalcopyrite materials in particular. We used the thin film solar cell simulation software SCAPS to enable the simulation of multivalent defects with up to five different charge states.Algorithms enabled us to simulate an arbitrary number of possible states of load. The presented solution method avoids numerical inaccuracies caused by the subtraction of two almost equal numbers. This new modelling facility is afterwards used to investigate the consequences of the multivalent character of defects for the simulation of chalcopyrite based CIGS. The capacitance increase with the evolution of the number of defects C- f curves have found to have defect dependence.

  19. Vaping cannabis (marijuana): parallel concerns to e-cigs?

    Science.gov (United States)

    Budney, Alan J; Sargent, James D; Lee, Dustin C

    2015-11-01

    The proliferation of vaporization ('vaping') as a method for administering cannabis raises many of the same public health issues being debated and investigated in relation to e-cigarettes (e-cigs). Good epidemiological data on the prevalence of vaping cannabis are not yet available, but with current trends towards societal approval of medicinal and recreational use of cannabis, the pros and cons of vaping cannabis warrant study. As with e-cigs, vaping cannabis portends putative health benefits by reducing harm from ingesting toxic smoke. Indeed, vaping is perceived and being sold as a safer way to use cannabis, despite the lack of data on the health effects of chronic vaping. Other perceived benefits include better taste, more efficient and intense effects and greater discretion which allows for use in more places. Unfortunately, these aspects of vaping could prompt an increased likelihood of trying cannabis, earlier age of onset, more positive initial experiences, and more frequent use, thereby increasing the probability of problematic use or addiction. Sales and marketing of vaping devices with no regulatory guidelines, especially related to advertising or product development targeting youth, parallels concerns under debate related to e-cigs and youth. Thus, the quandary of whether or not to promote vaping as a safer method of cannabis administration for those wishing to use cannabis, and how to regulate vaping and vaping devices, necessitates substantial investigation and discussion. Addressing these issues in concert with efforts directed towards e-cigs may save time and energy and result in a more comprehensive and effective public health policy on vaping.

  20. Vaping cannabis (marijuana): parallel concerns to e-cigs?

    Science.gov (United States)

    Budney, Alan J; Sargent, James D; Lee, Dustin C

    2015-11-01

    The proliferation of vaporization ('vaping') as a method for administering cannabis raises many of the same public health issues being debated and investigated in relation to e-cigarettes (e-cigs). Good epidemiological data on the prevalence of vaping cannabis are not yet available, but with current trends towards societal approval of medicinal and recreational use of cannabis, the pros and cons of vaping cannabis warrant study. As with e-cigs, vaping cannabis portends putative health benefits by reducing harm from ingesting toxic smoke. Indeed, vaping is perceived and being sold as a safer way to use cannabis, despite the lack of data on the health effects of chronic vaping. Other perceived benefits include better taste, more efficient and intense effects and greater discretion which allows for use in more places. Unfortunately, these aspects of vaping could prompt an increased likelihood of trying cannabis, earlier age of onset, more positive initial experiences, and more frequent use, thereby increasing the probability of problematic use or addiction. Sales and marketing of vaping devices with no regulatory guidelines, especially related to advertising or product development targeting youth, parallels concerns under debate related to e-cigs and youth. Thus, the quandary of whether or not to promote vaping as a safer method of cannabis administration for those wishing to use cannabis, and how to regulate vaping and vaping devices, necessitates substantial investigation and discussion. Addressing these issues in concert with efforts directed towards e-cigs may save time and energy and result in a more comprehensive and effective public health policy on vaping. PMID:26264448

  1. Thin Film CIGS and CdTe Photovoltaic Technologies: Commercialization, Critical Issues, and Applications; Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Ullal, H. S.; von Roedern, B.

    2007-09-01

    We report here on the major commercialization aspects of thin-film photovoltaic (PV) technologies based on CIGS and CdTe (a-Si and thin-Si are also reported for completeness on the status of thin-film PV). Worldwide silicon (Si) based PV technologies continues to dominate at more than 94% of the market share, with the share of thin-film PV at less than 6%. However, the market share for thin-film PV in the United States continues to grow rapidly over the past several years and in CY 2006, they had a substantial contribution of about 44%, compared to less than 10% in CY 2003. In CY 2007, thin-film PV market share is expected to surpass that of Si technology in the United States. Worldwide estimated projections for CY 2010 are that thin-film PV production capacity will be more than 3700 MW. A 40-MW thin-film CdTe solar field is currently being installed in Saxony, Germany, and will be completed in early CY 2009. The total project cost is Euro 130 million, which equates to an installed PV system price of Euro 3.25/-watt averaged over the entire solar project. This is the lowest price for any installed PV system in the world today. Critical research, development, and technology issues for thin-film CIGS and CdTe are also elucidated in this paper.

  2. An analysis of glass–glass CIGS manufacturing costs

    Energy Technology Data Exchange (ETDEWEB)

    Horowitz, Kelsey A. W.; Fu, Ran; Woodhouse, Michael

    2016-09-01

    This article examines current cost drivers and potential avenues to reduced cost for monolithic, glass-glass Cu(In,Ga)(Se,S)2 (CIGS) modules by constructing a comprehensive bottom-up cost model. For a reference case where sputtering plus batch sulfurization after selenization (SAS) is employed, we compute a manufacturing cost of $69/m2 if the modules are made in the United States at a 1 GW/year production volume. At 14% module efficiency, this corresponds to a manufacturing cost of $0.49/WDC and a minimum sustainable price (MSP) of $0.67/WDC. We estimate that MSP could vary within +/-20% of this value given the range of quoted input prices, and existing variations in module design, manufacturing processes, and manufacturing location. Potential for reduction in manufacturing costs to below $0.40/WDC may be possible if average production module efficiencies can be increased above 17% without increasing $/m2 costs; even lower costs could be achieved if $/m2 costs could be reduced, particularly via innovations in the CIGS deposition process or balance-of-module elements. We present the impact on cost of regional factors, CIGS deposition method, device design, and price fluctuations. One metric of competitiveness-levelized cost of energy (LCOE) -- is also assessed for several U.S. locations and compared to that of standard multi-crystalline silicon (m(c-Si)) and cadmium telluride (CdTe).

  3. A Novel Semiconductor CIGS Photovoltaic Material and Thin-Film ED Technology

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In order to achieve low-cost high-efficiency thin-film solar cells, a novel Semiconductor Photovoltaic (PV) active material CuIn1-xGaxSe2 (CIGS) and thin-film Electro-Deposition (ED) technology is explored. Firstly,the PV materials and technologies is investigated, then the detailed experimental processes of CIGS/Mo/glass structure by using the novel ED technology and the results are reported. These results shows that high quality CIGS polycrystalline thin-films can be obtained by the ED method, in which the polycrystalline CIGS is definitely identified by the (112), (204, 220) characteristic peaks of the tetragonal structure, the continuous CIGS thin-film layers with particle average size of about 2μm of length and around 1.6μm of thickness. The thickness and solargrade quality of CIGS thin-films can be produced with good repeatability. Discussion and analysis on the ED technique, CIGS energy band and sodium (Na) impurity properties, were also performed. The alloy CIGS exhibits not only increasing band-gap with increasing x, but also a change in material properties that is relevant to the device operation. The beneficial impurity Na originating from the low-cost soda-lime glass substrate becomes one prerequisite for high quality CIGS films. These novel material and technology are very useful for low-cost high-efficiency thin-film solar cells and other devices.

  4. Developing Market Opportunities for Flexible Rooftop Applications of PV Using Flexible CIGS Technology: Market Considerations

    Energy Technology Data Exchange (ETDEWEB)

    Sabnani, L.; Skumanich, A.; Ryabova, E.; Noufi, R.

    2011-01-01

    There has been a recent upsurge in developments for building-integrated phototovoltaics (BiPV) roof top materials based on CIGS. Several new companies have increased their presence and are looking to bring products to market for this application in 2011. For roof-top application, there are significant key requirements beyond just having good conversion efficiency. Other attributes include lightweight, as well as moisture-proof, and fully functionally reliable. The companies bringing these new BIPV/BAPV products need to ensure functionality with a rigorous series of tests, and have an extensive set of 'torture' tests to validate the capability. There is a convergence of form, aesthetics, and physics to ensure that the CIGS BiPV deliver on their promises. This article will cover the developments in this segment of the BiPV market and delve into the specific tests and measurements needed to characterize the products. The potential market sizes are evaluated and the technical considerations developed.

  5. Process parameter impact on properties of sputtered large-area Mo bilayers for CIGS thin film solar cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Badgujar, Amol C.; Dhage, Sanjay R., E-mail: dhage@arci.res.in; Joshi, Shrikant V.

    2015-08-31

    Copper indium gallium selenide (CIGS) has emerged as a promising candidate for thin film solar cells, with efficiencies approaching those of silicon-based solar cells. To achieve optimum performance in CIGS solar cells, uniform, conductive, stress-free, well-adherent, reflective, crystalline molybdenum (Mo) thin films with preferred orientation (110) are desirable as a back contact on large area glass substrates. The present study focuses on cylindrical rotating DC magnetron sputtered bilayer Mo thin films on 300 mm × 300 mm soda lime glass (SLG) substrates. Key sputtering variables, namely power and Ar gas flow rates, were optimized to achieve best structural, electrical and optical properties. The Mo films were comprehensively characterized and found to possess high degree of thickness uniformity over large area. Best crystallinity, reflectance and sheet resistance was obtained at high sputtering powers and low argon gas flow rates, while mechanical properties like adhesion and residual stress were found to be best at low sputtering power and high argon gas flow rate, thereby indicating a need to arrive at a suitable trade-off during processing. - Highlights: • Sputtering of bilayer molybdenum thin films on soda lime glass • Large area deposition using rotating cylindrical direct current magnetron • Trade of sputter process parameters power and pressure • High uniformity of thickness and best electrical properties obtained • Suitable mechanical and optical properties of molybdenum are achieved for CIGS application.

  6. Alternative Window Schemes for CuInSe2-Based Solar Cells Final Report: 3 November 1995-December 1997; FINAL

    International Nuclear Information System (INIS)

    This work demonstrated high-efficiency CIGS cells based on highly resistive ZnO buffer layers grown by MOCVD. One cell based on NREL CIGS and a ZnO buffer layer exhibited an active-area efficiency of nearly 14%. This result is one of the best efficiencies reported for a ''direct'' ZnO/CIGS cell made with a vacuum process

  7. 铜铟镓硒(CIGS)薄膜太阳能电池的研究进展%Progress in Research of CIGS Thin Film Solar Cells

    Institute of Scientific and Technical Information of China (English)

    王波; 刘平; 李伟; 马凤仓; 刘新宽; 陈小红

    2011-01-01

    综述了CIGS薄膜太阳能电池近年来的研究进展.概述了CIGS薄膜的组织结构、性能特性及其之间的联系;介绍了CIGS薄膜吸收层的多种制备方法,如多元共蒸发法、溅射后硒化法、电沉积法、喷涂高温分解法等;概述了Na掺杂对CIGS电池性能的促进作用及其机理;总结了柔性衬底CIGS薄膜太阳能电池的研究情况;最后从理论和实验研究方面展望了CIGS薄膜太阳能电池的研究方向.%The recent progress of CIGS thin film solar cells is reviewed. The microstructure, properties and their relations of CIGS are summarized. Various preparation methods of CIGS absorber layer, such as co-evaporation, selenization after sputtering, electrodeposition, and spray pyrolysis etc are introduced. The influence of doping Na in performance and its mechanism of CIGS cells are summarized. The research of flexible CIGS cells are summed up, and the theoretical and experimental research directions of CIGS thin film solar cells are finally prospected.

  8. Non-Stoichiometric Amorphous Indium Selenide Thin Films as a Buffer Layer for CIGS Solar Cells with Various Temperatures in Rapid Thermal Annealing.

    Science.gov (United States)

    Yoo, Myoung Han; Kim, Nam-Hoon

    2016-05-01

    The conventional structure of most of copper indium gallium diselenide (Culn(1-x)Ga(x)Se2, CIGS) solar cells includes a CdS thin film as a buffer layer. Cd-free buffer layers have attracted great interest for use in photovoltaic applications to avoid the use of hazardous and toxic materials. The RF magnetron sputtering method was used with an InSe2 compound target to prepare the indium selenide precursor. Rapid thermal annealing (RTA) was conducted in ambient N2 gas to control the concentration of volatile Se from the precursor with a change in temperature. The nature of the RTA-treated indium selenide thin films remained amorphous under annealing temperatures of ≤ 700 degrees C. The Se concentration of the RTA-treated specimens demonstrated an opposite trend to the annealing temperature. The optical transmittance and band gap energies were 75.33% and 2.451-3.085 eV, respectively, and thus were suitable for the buffer layer. As the annealing temperature increased, the resistivity decreased by an order-of-magnitude from 10(4) to 10(1) Ω-cm. At lower Se concentrations, the conductivity abruptly changed from p-type to n-type without crystallite formation in the amorphous phase, with the carrier concentration in the order of 10(17) cm(-3). PMID:27483873

  9. Molybdenum Back-Contact Optimization for CIGS Thin Film Solar Cell

    Directory of Open Access Journals (Sweden)

    J.R. Ray

    2011-01-01

    Full Text Available Molybdenum (Mo thin films are most widely used as an ohmic back-contact in the copper indium diselenide (CIS and its alloy copper indium gallium diselenide (CIGS based thin film solar cell. Radio frequency (RF magnetron sputtering system used to deposit Mo thin films on soda lime glass substrate. The deposition was carried out using argon (Ar gas at different Ar controlled (working pressures (1 mTorr to 10 mTorr and at different RF powers (60 W to 100 W. The influence of both the working pressure and the RF power on the Mo thin films was studied by investigating its structural, morphological, electrical, and optical measurements. The results reveal that a stress-free, low-sheet-resistance (~1 Ω/cm2, and reflecting (~ 55 % Mo thin film was observed at 1 mTorr working pressure and 100 W RF power.

  10. Development and manufacture of reactive-transfer-printed CIGS photovoltaic modules

    Science.gov (United States)

    Eldada, Louay; Sang, Baosheng; Lu, Dingyuan; Stanbery, Billy J.

    2010-09-01

    In recent years, thin-film photovoltaic (PV) companies started realizing their low manufacturing cost potential, and grabbing an increasingly larger market share from multicrystalline silicon companies. Copper Indium Gallium Selenide (CIGS) is the most promising thin-film PV material, having demonstrated the highest energy conversion efficiency in both cells and modules. However, most CIGS manufacturers still face the challenge of delivering a reliable and rapid manufacturing process that can scale effectively and deliver on the promise of this material system. HelioVolt has developed a reactive transfer process for CIGS absorber formation that has the benefits of good compositional control, high-quality CIGS grains, and a fast reaction. The reactive transfer process is a two stage CIGS fabrication method. Precursor films are deposited onto substrates and reusable print plates in the first stage, while in the second stage, the CIGS layer is formed by rapid heating with Se confinement. High quality CIGS films with large grains were produced on a full-scale manufacturing line, and resulted in high-efficiency large-form-factor modules. With 14% cell efficiency and 12% module efficiency, HelioVolt started to commercialize the process on its first production line with 20 MW nameplate capacity.

  11. Flexible CIGS solar cells and mini-modules (Flexcim)

    Energy Technology Data Exchange (ETDEWEB)

    Tiwari, A. N.

    2007-08-15

    This final report for the Swiss Federal Office of Energy (SFOE) reports on a project that has contributed significantly to further developments in the field of Cu(In,Ga)Se{sub 2} thin film solar cells on flexible substrates such as plastic and metal foils. Process optimisation at low temperature deposition conditions is reported on that have resulted in a new world record of the highest achieved solar conversion efficiency for any solar cell on plastic substrate: cells with an efficiency of 14.1% were obtained. Efficiencies beyond 15% are to be sought for by the reduction of reflection losses. The results obtained are presented in both illustrations and in graphical form. The authors state that more work, especially on up-scaling of CIGS deposition and further increasing the efficiency of flexible solar modules, is needed.

  12. Cost and Potential of Monolithic CIGS Photovoltaic Modules

    Energy Technology Data Exchange (ETDEWEB)

    Horowitz, Kelsey; Woodhouse, Michael

    2015-06-17

    A bottom-up cost analysis of monolithic, glass-glass Cu(In,Ga)(Se,S)2 (CIGS) modules is presented, illuminating current cost drivers for this technology and possible pathways to reduced cost. At 14% module efficiency, for the case of U.S. manufacturing, a manufacturing cost of $0.56/WDC and a minimum sustainable price of $0.72/WDC were calculated. Potential for reduction in manufacturing costs to below $0.40/WDC in the long-term may be possible if module efficiency can be increased without significant increase in $/m2 costs. The levelized cost of energy (LCOE) in Phoenix, AZ under different conditions is assessed and compared to standard c-Si.

  13. High-Efficiency CdTe and CIGS Thin-Film Solar Cells: Highlights and Challenges; Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Noufi, R.; Zweibel, K.

    2006-05-01

    Thin-film photovoltaic (PV) modules of CdTe and Cu(In,Ga)Se2 (CIGS) have the potential to reach cost-effective PV-generated electricity. These technologies have transitioned from the laboratory to the market place. Pilot production and first-time manufacturing are ramping up to higher capacity and enjoying a flood of venture-capital funding. CIGS solar cells and modules have achieved 19.5% and 13% efficiencies, respectively. Likewise, CdTe cells and modules have reached 16.5% and 10.2% efficiencies, respectively. Even higher efficiencies from the laboratory and from the manufacturing line are only a matter of time. Manufacturing-line yield continues to improve and is surpassing 85%. Long-term stability has been demonstrated for both technologies; however, some failures in the field have also been observed, emphasizing the critical need for understanding degradation mechanisms and packaging options. The long-term potential of the two technologies require R&D emphasis on science and engineering-based challenges to find solutions to achieve targeted cost-effective module performance, and in-field durability. Some of the challenges are common to both, e.g., in-situ process control and diagnostics, thinner absorber, understanding degradation mechanisms, protection from water vapor, and innovation in high-speed processing and module design. Other topics are specific to the technology, such as lower-cost and fast-deposition processes for CIGS, and improved back contact and voltage for CdTe devices.

  14. Integration of Solar Cells on Top of CMOS Chips - Part II: CIGS Solar Cells

    NARCIS (Netherlands)

    Lu, Jiwu; Liu, Wei; Kovalgin, Alexey Y.; Sun, Yun; Schmitz, Jurriaan

    2011-01-01

    We present the monolithic integration of deepsubmicrometer complementary metal–oxide–semiconductor (CMOS) microchips with copper indium gallium (di)selenide (CIGS) solar cells. Solar cells are manufactured directly on unpackaged CMOS chips. The microchips maintain comparable electronic performance,

  15. High efficiency CIGS and CIS cells with CVD ZnO buffer layers

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, L.C.; Lei, W.; Addis, F.W. [Washington State Univ./Tri-Cities, Richland, WA (United States); Shafarman, W.N. [Univ. of Delaware, Newark, DE (United States). Inst. of Energy Conversion; Contreras, M.A.; Ramanathan, K. [National Renewable Energy Lab., Golden, CO (United States)

    1997-12-31

    This paper describes investigations of CIS and CIGS solar cells with ZnO buffer layers. These studies are a result of a team effort between investigators at Washington State University (WSU), the Institute of Energy Conversion (IEC) and the National Renewable Energy Laboratory (NREL). Cells with ZnO buffer layers were fabricated with both Siemens CIS and NREL CIGS substrates. An active area efficiency of 13.95% was achieved for a ZnO/CIGS cell. ZnO buffer layers are grown by reacting a zinc adduct with tetrahydrofuran using a two-step approach: growth of approximately 100 {angstrom} of ZnO at 250 C; and then growth of 500 to 700 {angstrom} of ZnO at 100 C. The high temperature step is necessary to achieve good cell performance. It appears that exposure of CIGS to hydrogen at 250 C may remove contaminants and/or passivate recombination centers on the surface and subsurface regions.

  16. An optimized efficient dual junction InGaN/CIGS solar cell: A numerical simulation

    Science.gov (United States)

    Farhadi, Bita; Naseri, Mosayeb

    2016-08-01

    The photovoltaic performance of an efficient double junction InGaN/CIGS solar cell including a CdS antireflector top cover layer is studied using Silvaco ATLAS software. In this study, to gain a desired structure, the different design parameters, including the CIGS various band gaps, the doping concentration and the thickness of CdS layer are optimized. The simulation indicates that under current matching condition, an optimum efficiency of 40.42% is achieved.

  17. Effect of Rapid Thermal Annealing of CIGS Thin Film as an Absorber Layer

    Directory of Open Access Journals (Sweden)

    J.R. Ray

    2013-05-01

    Full Text Available The influence of rapid post-deposition thermal annealing (500 °C for 2 minutes on the CIGS thin films of different thicknesses (0.4 to 1.0 m has been investigated. The deposition of CIGS is carried out using the flash evaporation at the substrate temperature of 250 °C. The as-grown and annealed CIGS is characterized by XRD, SEM, EDS, TEM, optical transmission, reflection, and electrical measurements. Lowering the thickness of CIGS absorber shows the remarkable influence on crystal structure, surface morphology, and composition of the overall film. Further improvement was observed by the rapid annealing process. Cu-rich composition was observed for annealed CIGS thin film having a thickness below 0.6 μm, while for 1.0 m thickness the composition is slightly Cu-poor and the compactly packed faceted grains observed. Optical band gap near to 1.05 eV and the electrical resistivity in the order of 104 Ωcm shows its future use as an absorber layer for CIGS solar cell. Furthermore, an attempt of making CIGS / CdS hetero-structure shows ideal behavior of the Schottky hetero-structure with the ideality factor of 1.5.

  18. Expanding Thermal Plasma Chemical Vapour Deposition of ZnO:Al Layers for CIGS Solar Cells

    Directory of Open Access Journals (Sweden)

    K. Sharma

    2014-01-01

    Full Text Available Aluminium-doped zinc oxide (ZnO:Al grown by expanding thermal plasma chemical vapour deposition (ETP-CVD has demonstrated excellent electrical and optical properties, which make it an attractive candidate as a transparent conductive oxide for photovoltaic applications. However, when depositing ZnO:Al on CIGS solar cell stacks, one should be aware that high substrate temperature processing (i.e., >200°C can damage the crucial underlying layers/interfaces (such as CIGS/CdS and CdS/i-ZnO. In this paper, the potential of adopting ETP-CVD ZnO:Al in CIGS solar cells is assessed: the effect of substrate temperature during film deposition on both the electrical properties of the ZnO:Al and the eventual performance of the CIGS solar cells was investigated. For ZnO:Al films grown using the high thermal budget (HTB condition, lower resistivities, ρ, were achievable (~5 × 10−4 Ω·cm than those grown using the low thermal budget (LTB conditions (~2 × 10−3 Ω·cm, whereas higher CIGS conversion efficiencies were obtained for the LTB condition (up to 10.9% than for the HTB condition (up to 9.0%. Whereas such temperature-dependence of CIGS device parameters has previously been linked with chemical migration between individual layers, we demonstrate that in this case it is primarily attributed to the prevalence of shunt currents.

  19. AMIGA project: Quantification of the isolation of 950 CIG galaxies

    CERN Document Server

    Verley, S; Verdes-Montenegro, L; Combes, F; Sabater, J; Sulentic, J; Bergond, G; Espada, D; Lisenfeld, U; Odewahn, S C

    2009-01-01

    The role of the environment on galaxy evolution is still not fully understood. In order to quantify and set limits on the role of nurture one must identify and study a sample of isolated galaxies. The AMIGA project "Analysis of the Interstellar Medium of Isolated GAlaxies" is doing a multi-wavelength study of a large sample of isolated galaxies in order to examine their interstellar medium and star formation activity. We processed data for 950 galaxies from the Catalogue of Isolated Galaxies (CIG, Karachentseva 1973) and evaluated their isolation using an automated star-galaxy classification procedure (down to M_B ~17.5) on large digitised POSS-I fields surrounding each isolated galaxy (within a projected radius of at least 0.5 Mpc). We defined, compared and discussed various criteria to quantify the degree of isolation for these galaxies: e.g. Karachentseva's revised criterion, local surface density computations, estimation of the external tidal force affecting each isolated galaxy. We found galaxies violati...

  20. Recycling of high purity selenium from CIGS solar cell waste materials.

    Science.gov (United States)

    Gustafsson, Anna M K; Foreman, Mark R StJ; Ekberg, Christian

    2014-10-01

    Copper indium gallium diselenide (CIGS) is a promising material in thin film solar cell production. To make CIGS solar cells more competitive, both economically and environmentally, in comparison to other energy sources, methods for recycling are needed. In addition to the generally high price of the material, significant amounts of the metals are lost in the manufacturing process. The feasibility of recycling selenium from CIGS through oxidation at elevated temperatures was therefore examined. During oxidation gaseous selenium dioxide was formed and could be separated from the other elements, which remained in solid state. Upon cooling, the selenium dioxide sublimes and can be collected as crystals. After oxidation for 1h at 800°C all of the selenium was separated from the CIGS material. Two different reduction methods for reduction of the selenium dioxide to selenium were tested. In the first reduction method an organic molecule was used as the reducing agent in a Riley reaction. In the second reduction method sulphur dioxide gas was used. Both methods resulted in high purity selenium. This proves that the studied selenium separation method could be the first step in a recycling process aimed at the complete separation and recovery of high purity elements from CIGS.

  1. Investigation of Some Transparent Metal Oxides as Damp Heat Protective Coating for CIGS Solar Cells: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Pern, F. J.; Yan, F.; Zaaunbrecher, B.; To, B.; Perkins, J.; Noufi, R.

    2012-10-01

    We investigated the protective effectiveness of some transparent metal oxides (TMO) on CIGS solar cell coupons against damp heat (DH) exposure at 85oC and 85% relative humidity (RH). Sputter-deposited bilayer ZnO (BZO) with up to 0.5-um Al-doped ZnO (AZO) layer and 0.2-um bilayer InZnO were used as 'inherent' part of device structure on CdS/CIGS/Mo/SLG. Sputter-deposited 0.2-um ZnSnO and atomic layer deposited (ALD) 0.1-um Al2O3 were used as overcoat on typical BZO/CdS/CIGS/Mo/SLG solar cells. The results were all negative -- all TMO-coated CIGS cells exhibited substantial degradation in DH. Combining the optical photographs, PL and EL imaging, SEM surface micro-morphology, coupled with XRD, I-V and QE measurements, the causes of the device degradations are attributed to hydrolytic corrosion, flaking, micro-cracking, and delamination induced by the DH moisture. Mechanical stress and decrease in crystallinity (grain size effect) could be additional degrading factors for thicker AZO grown on CdS/CIGS.

  2. Sodium-Doped Molybdenum Targets for Controllable Sodium Incorporation in CIGS Solar Cells: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Mansfield, L. M.; Repins, I. L.; Glynn, S.; Carducci, M. D.; Honecker, D. M.; Pankow, J.; Young, M.; DeHart, C.; Sundaramoorthy, R.; Beall, C. L.; To, B.

    2011-07-01

    The efficiency of Cu(In,Ga)Se2 (CIGS) solar cells is enhanced when Na is incorporated in the CIGS absorber layer. This work examines Na incorporation in CIGS utilizing Na-doped Mo sputtered from targets made with sodium molybdate-doped (MONA) powder. Mo:Na films with varying thicknesses were sputtered onto Mo-coated borosilicate glass (BSG) or stainless steel substrates for CIGS solar cells. By use of this technique, the Na content of CIGS can be varied from near-zero to higher than that obtained from a soda-lime glass (SLG) substrate. Targets and deposition conditions are described. The doped Mo films are analyzed, and the resulting devices are compared to devices fabricated on Mo-coated SLG as well as Mo-coated BSG with NaF. Completed devices utilizing MONA exceeded 15.7% efficiency without anti-reflective coating, which was consistently higher than devices prepared with the NaF precursor. Strategies for minimizing adhesion difficulties are presented.

  3. CIGS absorber layer with double grading Ga profile for highly efficient solar cells

    Science.gov (United States)

    Saadat, M.; Moradi, M.; Zahedifar, M.

    2016-04-01

    It is well-known that the band gap grading in CIGS solar cells is crucial for achieving highly efficient solar cells. We stimulate a CIGS solar cell and investigate the effects of the band gap grading on performance of the CIGS solar cell, where Ga/(Ga + In) ratio (GGI) at back (Cb) and front (Cf) of the absorber layer are considered constant. Our simulations show that by increasing the GGI at middle of CIGS absorber layer (Cm), the JSC decreases and VOC increases independent of the distance of the Cm from the back contact (Xm). For Cm lower than Cf, JSC increases and VOC decreases when the Xm shifts to the front of the CIGS layer. The behavior of JSC and VOC became reverse for the case of Cm greater than Cf. Almost in all of the structures, efficiency and FF have same behaviors. Our simulations show that the highest efficiency is obtained at Cm = 0.8 and Xm = 200 nm.

  4. The influence of Na on metastable defect kinetics in CIGS materials

    Energy Technology Data Exchange (ETDEWEB)

    Erslev, Peter T. [University of Oregon Physics Department, Eugene, Oregon (United States)], E-mail: perslev@uoregon.edu; Lee, Jin Woo [University of Oregon Physics Department, Eugene, Oregon (United States); Shafarman, William N. [Institute of Energy Conversion, University of Delaware, Newark, Delaware (United States); Cohen, J. David [University of Oregon Physics Department, Eugene, Oregon (United States)

    2009-02-02

    The electronic properties of matched pairs of Cu(In{sub x}Ga{sub 1-x})Se{sub 2} (CIGS) solar cells, with and without normal sodium levels, were studied by junction capacitance methods including admittance spectroscopy, drive level capacitance profiling (DLCP) and transient photocapacitance spectroscopy (TPC). The capacitance profiling measurements revealed a large deep defect density in the vicinity of the barrier interface that was likely responsible for the lower performance of the reduced Na samples. The metastable properties of CIGS solar cells were also examined, and these revealed marked differences between the two types of samples. These results directly address the predictions of theoretical microscopic models that have been proposed to account for metastable effects in CIGS.

  5. Fabrication of CIGS thin films by using spray pyrolysis and post-selenization

    International Nuclear Information System (INIS)

    We fabricated Cu(In1-xGax)Se2 (x: 0 ∼ 0.4) thin films by using ultrasonic spray pyrolysis and post-selenization. First, we made Cu(In1-xGax)S2 (x: 0 ∼ 0.4) films by ultrasonic spray pyrolysis under an air environment. Then, we converted as-sprayed Cu(In1-xGax)S2 (CIGS) films to Cu(In1-xGax)Se2 (CIGSe) films through post-selenization. For all Ga fractions, the sprayed CIGS films were well recrystallized into poly-crystalline CIGSe films with a dominant (112) texture, which was confirmed by X-ray diffraction, Raman spectroscopy and energy dispersive X-ray analyses. This result indicates that CIGSe films with any amount of Ga substitution can be made by converting sprayed CIGS to CIGSe with post-selenization.

  6. Recycling of high purity selenium from CIGS solar cell waste materials

    International Nuclear Information System (INIS)

    Highlights: • A new method for recycling of selenium from CIGS solar cell materials is presented. • Separation of selenium as selenium dioxide after heating in oxygen atmosphere. • Complete selenium separation after oxidation of <63 μm particles at 800 °C for 1 h. • After reduction of selenium dioxide the selenium purity was higher than 99.999 wt%. - Abstract: Copper indium gallium diselenide (CIGS) is a promising material in thin film solar cell production. To make CIGS solar cells more competitive, both economically and environmentally, in comparison to other energy sources, methods for recycling are needed. In addition to the generally high price of the material, significant amounts of the metals are lost in the manufacturing process. The feasibility of recycling selenium from CIGS through oxidation at elevated temperatures was therefore examined. During oxidation gaseous selenium dioxide was formed and could be separated from the other elements, which remained in solid state. Upon cooling, the selenium dioxide sublimes and can be collected as crystals. After oxidation for 1 h at 800 °C all of the selenium was separated from the CIGS material. Two different reduction methods for reduction of the selenium dioxide to selenium were tested. In the first reduction method an organic molecule was used as the reducing agent in a Riley reaction. In the second reduction method sulphur dioxide gas was used. Both methods resulted in high purity selenium. This proves that the studied selenium separation method could be the first step in a recycling process aimed at the complete separation and recovery of high purity elements from CIGS

  7. CIG-DB: the database for human or mouse immunoglobulin and T cell receptor genes available for cancer studies

    Directory of Open Access Journals (Sweden)

    Furue Motoki

    2010-07-01

    Full Text Available Abstract Background Immunoglobulin (IG or antibody and the T-cell receptor (TR are pivotal proteins in the immune system of higher organisms. In cancer immunotherapy, the immune responses mediated by tumor-epitope-binding IG or TR play important roles in anticancer effects. Although there are public databases specific for immunological genes, their contents have not been associated with clinical studies. Therefore, we developed an integrated database of IG/TR data reported in cancer studies (the Cancer-related Immunological Gene Database [CIG-DB]. Description This database is designed as a platform to explore public human and murine IG/TR genes sequenced in cancer studies. A total of 38,308 annotation entries for IG/TR proteins were collected from GenBank/DDBJ/EMBL and the Protein Data Bank, and 2,740 non-redundant corresponding MEDLINE references were appended. Next, we filtered the MEDLINE texts by MeSH terms, titles, and abstracts containing keywords related to cancer. After we performed a manual check, we classified the protein entries into two groups: 611 on cancer therapy (Group I and 1,470 on hematological tumors (Group II. Thus, a total of 2,081 cancer-related IG and TR entries were tabularized. To effectively classify future entries, we developed a computational method based on text mining and canonical discriminant analysis by parsing MeSH/title/abstract words. We performed a leave-one-out cross validation for the method, which showed high accuracy rates: 94.6% for IG references and 94.7% for TR references. We also collected 920 epitope sequences bound with IG/TR. The CIG-DB is equipped with search engines for amino acid sequences and MEDLINE references, sequence analysis tools, and a 3D viewer. This database is accessible without charge or registration at http://www.scchr-cigdb.jp/, and the search results are freely downloadable. Conclusions The CIG-DB serves as a bridge between immunological gene data and cancer studies, presenting

  8. The impact of atmospheric species on the degradation of CIGS solar cells

    NARCIS (Netherlands)

    Theelen, M.; Foster, C.; Steijvers, H.; Barreau, N.; Vroon, Z.; Zeman, M.

    2015-01-01

    CIGS solar cells were exposed to liquid water purged with the atmospheric gases carbon dioxide (CO2), oxygen (O2), nitrogen (N2) and air in order to investigate their chemical degradation behavior. The samples were analyzed by electrical, compositional and optical me

  9. Study the Effect of Annealing Temperature on Optical properties For CIGS Films

    Directory of Open Access Journals (Sweden)

    Harith I. Jaafer

    2015-07-01

    Full Text Available In this research CIGS films were obtained by a drop-coating method and subsequently annealed in nitrogen atmosphere .Optical management is a way to improve the solar cell performance .The optical properties of CIGS films were characterized by UV-vis. Study the optical properties of the deferent concentrations of liquid solutions of CIGS ink, and the absorption still constant from the wavelength range 400 to 600nm ,and then began increase gradually from wavelength range 650nm of all concentrations but it seems more strong absorption of concentration (100 % due to the content of Copper nitrate trihydrate. The transmittance of 50% ,and 100% concentrations is greater than 80 % and reach 100% between wavelength range 400 to 600nm,but it increase in 12%, and 25% concentrations and get up to 100% between wavelength range 350 to 600nm.Thus due to more homogeneity of liquid solutions of CIGS ink. Found that the effect of annealing at 525°C on absorption spectra of all concentrations (12.5, 25, 50, and 100% it’s still height and constant in the wavelength range 380–800 nm and the values of absorbance approximately between 120 to 200%, while the transmittance of all reduced and get the values under 10% of transmittance ,and the increasing of the concentrations at this temperature may be reduce of transmittance.

  10. Characterization of carrier concentration in CIGS solar cells by scanning capacitance microscopy

    International Nuclear Information System (INIS)

    Thin films of copper indium gallium selenide (CIGS) designed for highly efficient solar cell material were investigated to characterize the two-dimensional carrier distribution using scanning capacitance microscopy (SCM). We optimized a preparation method of the cross-section samples and concluded that bevel polishing by 25° to 30° was effective for crumbly polycrystalline materials such as CIGS, so as to provide not the surface property of cracked crystalline grains but the cross-section property of individual cut grains. Because of improvement in this preparation procedure, changes in carrier distribution have been observed directly in the active CIGS layer before and after turning on a 100 W halogen lamp irradiation. A calibration curve between carrier concentration N and SCM's dC/dV signals was applied for qualitatively calculating relative values of N in CIGS. Increased carrier concentration peaks on the grains were estimated to become about three times as high as those with the light on. (paper)

  11. Thin film CIGS photovoltaic modules: monolithic integration and advanced packaging for high performance, high reliability and low cost

    Science.gov (United States)

    Eldada, Louay

    2011-01-01

    In recent years, thin-film photovoltaic companies started realizing their low manufacturing cost potential, and have been grabbing an increasingly larger market share. Copper Indium Gallium Selenide (CIGS) is the most promising thin-film PV material, having demonstrated the highest energy conversion efficiency in both cells and modules. However, most CIGS manufacturers still face the challenge of delivering a reliable and rapid manufacturing process that can scale effectively and deliver on the promise of this material system. HelioVolt has developed a reactive transfer process for CIGS absorber formation that has the benefits of good compositional control, and a fast high-quality CIGS reaction. The reactive transfer process is a two stage CIGS fabrication method. Precursor films are deposited onto substrates and reusable cover plates in the first stage, while in the second stage the CIGS layer is formed by rapid heating with Se confinement. HelioVolt also developed best-in-class packaging technologies that provide unparalleled environmental stability. High quality CIGS films with large grains were fabricated on the production line, and high-performance highreliability monolithic modules with a form factor of 120 cm × 60 cm are being produced at high yield and low cost. With conversion efficiency levels around 14% for cells and 12% for modules, HelioVolt is commercializing the process on its first production line with 20 MW capacity, and is planning its next GW-scale factory.

  12. Characteristics of CIGS photovoltaic devices co-evaporated with various Se flux rates at low temperatures

    Science.gov (United States)

    Huang, Chia-Hua; Lin, Chun-Ping; Jan, Yueh-Lin

    2016-08-01

    Cu(In,Ga)Se2 (CIGS) films were prepared by a single-stage co-evaporation process at Se flux rates of 10 Å s-1, 20 Å s-1, and 30 Å s-1 and substrate temperatures ranging from 400 °C to 500 °C. The flux rates of the Cu, In, Ga, and Se were kept constant throughout each deposition of the films. The grain sizes, surface morphologies, and crystallinity of the CIGS films improved with increasing substrate temperatures or Se flux rates. The causes of the formation of voids on the surface of CIGS films deposited with a low Se flux rate of 10 Å s-1 at substrate temperatures of 475 °C and 500 °C were addressed. The higher Se flux rates of 20 Å s-1 and 30 Å s-1 repressed the formation of voids for the CIGS films deposited at the relatively higher substrate temperatures of 475 °C and 500 °C. The conversion efficiencies of CIGS solar cells were significantly improved by increasing the substrate temperatures or the Se flux rates, largely contributed from the enhancement of the open-circuit voltage and fill factor because of the restraint of the carrier recombination. The short-circuit current densities were slightly enhanced by the increment of the substrate temperatures or the Se flux rates, resulting from the improved crystalline quality of the CIGS films. Moreover, the EQE results suggest that the effective carrier-diffusion lengths of the films deposited at the relatively high substrate temperatures were increased, leading to the enhancement of the short-circuit current density. The efficiencies of CIGS solar cells prepared with a Se flux rate of 10 Å s-1 improved from 10% to 12.4% when the substrate temperatures increased from 400 °C to 500 °C. The efficiencies of cells deposited at the substrate temperature of 500 °C improved to 15.4% as the Se flux rates increased from 10 Å s-1 to 30 Å s-1.

  13. Significant effect of substrate temperature on the phase structure, optical and electrical properties of RF sputtered CIGS films

    Energy Technology Data Exchange (ETDEWEB)

    Yu Zhou; Yan Yong; Li Shasha; Zhang Yanxia; Yan Chuanpeng; Liu Lian; Zhang Yong [Key Laboratory of Magnetic Suspension Technology and Maglev Vehicle, Ministry of Education, Superconductivity and New energy R and D Center (SNERDC), Mail Stop 165, Southwest Jiaotong University, Chengdu 610031 (China); Zhao Yong, E-mail: yzhao@swjtu.edu.cn [Key Laboratory of Magnetic Suspension Technology and Maglev Vehicle, Ministry of Education, Superconductivity and New energy R and D Center (SNERDC), Mail Stop 165, Southwest Jiaotong University, Chengdu 610031 (China); School of Materials Science and Engineering, University of New South Wales, Sydney 2052, NSW (Australia)

    2013-01-01

    Highlights: Black-Right-Pointing-Pointer Secondary phase exist in the RF sputtered CIGS films as it deposited at 150 Degree-Sign C and 500 Degree-Sign C. Black-Right-Pointing-Pointer CIGS films deposited beyond 350 Degree-Sign C show (1 1 2) prefer orientation. Black-Right-Pointing-Pointer E{sub g} of the CIGS films increased with the increase of substrate temperature. Black-Right-Pointing-Pointer Conductivity of the films is affected by 'variable range hopping' mechanism. - Abstract: This work studied the effect of substrate temperature on the phase structure, optical and electrical properties of the one-step radio frequency sputtered Cu(In,Ga)Se{sub 2} (CIGS) thin films. X-ray diffraction (XRD) analysis revealed that all the deposited CIGS films are chalcopyrite phase with polycrystalline structure. The films deposited beyond the substrate temperature of 350 Degree-Sign C show (1 1 2) prefer orientation. Raman spectra reveal that the 150 Degree-Sign C deposited CIGS film coexists with Cu{sub 2-x}Se phase and the 500 Degree-Sign C deposited film contains ordered defect compound (ODC) phase. With the increase of substrate temperature, energy band gap of the CIGS film increase from 0.99 to 1.27 eV. Films deposited at higher temperature exhibit larger electrical conductivity. Conductivity of the CIGS films is dominated by 'variable range hopping' mechanism. The disorder in our CIGS the films is associated with the formation of intrinsic defects such as V{sub Se} and In{sub Cu} for their low formation energy.

  14. Impacts of electron irradiation on the optical and electrical properties of CIGS thin films and solar cells

    International Nuclear Information System (INIS)

    Full text : A thin film solar cell composed of polycrystalline Cu(In,Ga)Se2 (CIGS) is essentially light-weight and shows high conversion efficiency and excellent radiation tolerance. These characteristics lead to CIGS solar cells very attractive for space applications. However, only a few irradiation studies have been carried out on CIGS thin films and entire solar cell structure, resulting in limited knowledge on the mechanisms responsible for the irradiation-induced damage. In addition, the cell performance is known to change due to the damp heat and/or light soaking effects. Accordingly, understanding the degradation mechanisms of CIGS, ZnO, a buffer, Mo, and even glass components is necessary for not only space use but also commercial use. In this presentation, electron irradiation effects will be discussed for CIGS solar cells and each layer that composed the CIGS solar cell structure such as CIGS, CdS, undoped ZnO, and Ga- or Al-doped ZnO films. Electron irradiation experiments were carried out using the DYNAMITRON electron accelerator. The electron energy was fixed at 2 MeV and the fluence was varied between 1 * 1013 and 1 * 1018 cm-2. All the irradiated CIGS films exhibited common PL peaks originating from donor to acceptor transitions. PL peak intensity due to Cu-related point defects, which did not affect solar cell performance significantly, increased in CIGS thin films with increasing electron irradiation. Conversely, transmittance spectra of all the irradiated ZnO and ZnO:Al films did not change by the electron irradiation up to 6 * 1017 cm-2. The normalized performance parameters of the irradiated CIGS solar cell such as Voc, Jsc, and η are shown in article as a function of irradiation fluence. η tended to decrease in comparison with Voc and Jsc for large irradiation fluence. Shunt resistance and series resistance of the CIGS solar cells degraded even though the resistivity of each layer did not change after electron irradiation. The result

  15. Alternative Window Schemes for CuInSe2-Based Solar Cells Final Report: 3 November 1995-December 1997

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, L.C. (Electronic Materials Laboratory: Washington State University at Tri-Cities)

    1998-10-26

    This work demonstrated high-efficiency CIGS cells based on highly resistive ZnO buffer layers grown by MOCVD. One cell based on NREL CIGS and a ZnO buffer layer exhibited an active-area efficiency of nearly 14%. This result is one of the best efficiencies reported for a ''direct'' ZnO/CIGS cell made with a vacuum process.

  16. Identification and Validation of Novel Hedgehog-Responsive Enhancers Predicted by Computational Analysis of Ci/Gli Binding Site Density.

    Directory of Open Access Journals (Sweden)

    Katherine Gurdziel

    Full Text Available The Hedgehog (Hh signaling pathway directs a multitude of cellular responses during embryogenesis and adult tissue homeostasis. Stimulation of the pathway results in activation of Hh target genes by the transcription factor Ci/Gli, which binds to specific motifs in genomic enhancers. In Drosophila, only a few enhancers (patched, decapentaplegic, wingless, stripe, knot, hairy, orthodenticle have been shown by in vivo functional assays to depend on direct Ci/Gli regulation. All but one (orthodenticle contain more than one Ci/Gli site, prompting us to directly test whether homotypic clustering of Ci/Gli binding sites is sufficient to define a Hh-regulated enhancer. We therefore developed a computational algorithm to identify Ci/Gli clusters that are enriched over random expectation, within a given region of the genome. Candidate genomic regions containing Ci/Gli clusters were functionally tested in chicken neural tube electroporation assays and in transgenic flies. Of the 22 Ci/Gli clusters tested, seven novel enhancers (and the previously known patched enhancer were identified as Hh-responsive and Ci/Gli-dependent in one or both of these assays, including: Cuticular protein 100A (Cpr100A; invected (inv, which encodes an engrailed-related transcription factor expressed at the anterior/posterior wing disc boundary; roadkill (rdx, the fly homolog of vertebrate Spop; the segment polarity gene gooseberry (gsb; and two previously untested regions of the Hh receptor-encoding patched (ptc gene. We conclude that homotypic Ci/Gli clustering is not sufficient information to ensure Hh-responsiveness; however, it can provide a clue for enhancer recognition within putative Hedgehog target gene loci.

  17. Characteristics of Cu(In,Ga)Se{sub 2} (CIGS) thin films deposited by a direct solution coating process

    Energy Technology Data Exchange (ETDEWEB)

    Park, Myoung Guk [Photovoltaic Center, Korea Institute of Energy Research, 71-2 JangDong, YuseongGu, DaeJeon 305-343 (Korea, Republic of); Ahn, Se Jin, E-mail: swisstel@kier.re.kr [Photovoltaic Center, Korea Institute of Energy Research, 71-2 JangDong, YuseongGu, DaeJeon 305-343 (Korea, Republic of); Yun, Jae Ho; Gwak, Jihye; Cho, Ara; Ahn, Seoung Kyu; Shin, Keeshik [Photovoltaic Center, Korea Institute of Energy Research, 71-2 JangDong, YuseongGu, DaeJeon 305-343 (Korea, Republic of); Nam, Dahyun; Cheong, Hyeonsik [Department of Physics, Sogang University, Seoul 121-742 (Korea, Republic of); Yoon, Kyunghoon [Photovoltaic Center, Korea Institute of Energy Research, 71-2 JangDong, YuseongGu, DaeJeon 305-343 (Korea, Republic of)

    2012-02-05

    Highlights: Black-Right-Pointing-Pointer Double layered CIGS/carbon films prepared by a direct solution coating. Black-Right-Pointing-Pointer Controllability of compositions of the CIGS layer. Black-Right-Pointing-Pointer Effects of Cu and Ga contents on properties of the CIGS layer. Black-Right-Pointing-Pointer Structure of the bottom carbon layer. - Abstract: Cu(In,Ga)Se{sub 2} (CIGS) thin films were formed by a direct non-vacuum coating and a subsequent selenization of low cost precursor solutions, and their compositional, structural and optical properties were characterized. Selenized films showed a double-layered structure with an upper layer of chalcopyrite CIGS and an amorphous bottom layer mainly composed of carbon. For the upper CIGS layer, good compositional controllability for Cu and Ga was confirmed by linear relationship between metal ratios of the precursor solution and those of the selenized films. Effects of Cu and Ga contents on structural and optical properties of the films were also characterized by X-ray diffraction (XRD), Raman and photoluminescence (PL) analyses, and the results were interpreted by defect supercluster formation (V{sub Cu}-In{sub Cu}) in Cu-deficient films and mass and size difference between In and Ga, respectively. Further, the bottom layer was found to be mostly composed of conductive amorphous carbon, which is the main current flow path in the completed solar cells.

  18. Control over the preferred orientation of CIGS films deposited by magnetron sputtering using a wetting layer

    Science.gov (United States)

    Yan, Yong; Jiang, Fan; Liu, Lian; Yu, Zhou; Zhang, Yong; Zhao, Yong

    2016-01-01

    A growth method is presented to control the preferred orientation in chalcopyrite CuIn x Ga1- x Se2 (CIGS) thin films grown by magnetron sputtering. Films with (220/204) and (112) preferred orientation as well as randomly oriented films were prepared. The effects of an In2Se3 wetting layer and the working pressure on the texture transition phenomena were examined. A large-grained CIGS film with (220/204) texture was formed at 400°C with the inclusion of a thin (80 nm) In2Se3 layer and liquid phase (excess copper selenide phase) formation, and the reaction mechanism is proposed. The device deposited at 2.0 Pa on an In2Se3 layer exhibited the optimal electrical properties. [Figure not available: see fulltext.

  19. Chemistry in isolation: High CCH/HCO+ line ratio in the AMIGA galaxy CIG 638

    CERN Document Server

    Martin, S; Aladro, R; Espada, D; Argudo-Fernandez, M; Kramer, C; Scott, T C

    2014-01-01

    Multi-molecule observations towards an increasing variety of galaxies have been showing that the relative molecular abundances are affected by the type of activity. However, these studies are biased towards bright active galaxies, which are typically in interaction. We study the molecular composition of one of the most isolated galaxies in the local Universe where the physical and chemical properties of their molecular clouds have been determined by intrinsic mechanisms. We present 3 mm broad band observations of the galaxy CIG 638, extracted from the AMIGA sample of isolated galaxies. The emission of the J=1-0 transitions of CCH, HCN, HCO+, and HNC are detected. Integrated intensity ratios between these line are compared with similar observations from the literature towards active galaxies including starburst galaxies (SB), active galactic nuclei (AGN), luminous infrared galaxies (LIRG), and GMCs in M33. A significantly high ratio of CCH with respect to HCN, HCO+, and HNC is found towards CIG 638 when compar...

  20. Alternative back contact for CIGS solar cells built on sodium-free substrates

    OpenAIRE

    Söderström, Wilhelm

    2011-01-01

    It is widely known that the element sodium plays a vital role in providing highefficiency CIGS solar cells and that when cells are built on sodium free substrates theyneed an alternative (a substitute) sodium source. In this study a molybdenum-sodiumcompound has been deposited, investigated and evaluated as an alternative backcontact layer containing sodium. The compound had a 5 at % sodium concentrationand it was manufactured by an Austrian company called Plansee. The aim of the studywas to ...

  1. In-situ growth of a CdS window layer by vacuum thermal evaporation for CIGS thin film solar cell applications

    International Nuclear Information System (INIS)

    Highly crystalline and transparent CdS films are grown by utilizing the vacuum thermal evaporation (VTE) method. The structural, surface morphological, and optical properties of the films are studied and compared with those prepared by chemical bath deposition (CBD). It is found that the films deposited at a high substrate temperature (200 °C) have a preferential orientation along (002) which is consistent with CBD-grown films. Absorption spectra reveal that the films are highly transparent and the optical band gap values are found to be in a range of 2.44 eV–2.56 eV. CuIn1−xGaxSe2 (CIGS) solar cells with in-situ VTE-grown CdS films exhibit higher values of Voc together with smaller values of Jsc than those from CBD. Eventually the conversion efficiency and fill factor become slightly better than those from the CBD method. Our work suggests that the in-situ thermal evaporation method can be a competitive alternative to the CBD method, particularly in the physical- and vacuum-based CIGS technology. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  2. Comparison on cellular mechanisms of iron and cadmium accumulation in rice: prospects for cultivating Fe-rich but Cd-free rice.

    Science.gov (United States)

    Gao, Lei; Chang, Jiadong; Chen, Ruijie; Li, Hubo; Lu, Hongfei; Tao, Longxing; Xiong, Jie

    2016-12-01

    Iron (Fe) is essential for rice growth and humans consuming as their staple food but is often deficient because of insoluble Fe(III) in soil for rice growth and limited assimilation for human bodies, while cadmium (Cd) is non-essential and toxic for rice growth and humans if accumulating at high levels. Over-accumulated Cd can cause damage to human bodies. Selecting and breeding Fe-rich but Cd-free rice cultivars are ambitious, challenging and meaningful tasks for researchers. Although evidences show that the mechanisms of Fe/Cd uptake and accumulation in rice are common to some extent as a result of similar entry routes within rice, an increasing number of researchers have discovered distinct mechanisms between Fe/Cd uptake and accumulation in rice. This comprehensive review systematically elaborates and compares cellular mechanisms of Fe/Cd uptake and accumulation in rice, respectively. Mechanisms for maintaining Fe homeostasis and Cd detoxicification are also elucidated. Then, effects of different fertilizer management on Fe/Cd accumulation in rice are discussed. Finally, this review enumerates various approaches for reducing grain Cd accumulation and enhancing Fe content in rice. In summary, understanding of discrepant cellular mechanisms of Fe/Cd accumulation in rice provides guidance for cultivating Fe-fortified rice and has paved the way to develop rice that are tolerant to Cd stress, aiming at breeding Fe-rich but Cd-free rice.

  3. Comparison on cellular mechanisms of iron and cadmium accumulation in rice: prospects for cultivating Fe-rich but Cd-free rice.

    Science.gov (United States)

    Gao, Lei; Chang, Jiadong; Chen, Ruijie; Li, Hubo; Lu, Hongfei; Tao, Longxing; Xiong, Jie

    2016-12-01

    Iron (Fe) is essential for rice growth and humans consuming as their staple food but is often deficient because of insoluble Fe(III) in soil for rice growth and limited assimilation for human bodies, while cadmium (Cd) is non-essential and toxic for rice growth and humans if accumulating at high levels. Over-accumulated Cd can cause damage to human bodies. Selecting and breeding Fe-rich but Cd-free rice cultivars are ambitious, challenging and meaningful tasks for researchers. Although evidences show that the mechanisms of Fe/Cd uptake and accumulation in rice are common to some extent as a result of similar entry routes within rice, an increasing number of researchers have discovered distinct mechanisms between Fe/Cd uptake and accumulation in rice. This comprehensive review systematically elaborates and compares cellular mechanisms of Fe/Cd uptake and accumulation in rice, respectively. Mechanisms for maintaining Fe homeostasis and Cd detoxicification are also elucidated. Then, effects of different fertilizer management on Fe/Cd accumulation in rice are discussed. Finally, this review enumerates various approaches for reducing grain Cd accumulation and enhancing Fe content in rice. In summary, understanding of discrepant cellular mechanisms of Fe/Cd accumulation in rice provides guidance for cultivating Fe-fortified rice and has paved the way to develop rice that are tolerant to Cd stress, aiming at breeding Fe-rich but Cd-free rice. PMID:27502932

  4. Improving the efficiency of copper indium gallium (Di-selenide (CIGS solar cells through integration of a moth-eye textured resist with a refractive index similar to aluminum doped zinc oxide

    Directory of Open Access Journals (Sweden)

    M. Burghoorn

    2014-12-01

    Full Text Available Textured transparent conductors are widely used in thin-film silicon solar cells. They lower the reflectivity at interfaces between different layers in the cell and/or cause an increase in the path length of photons in the Si absorber layer, which both result in an increase in the number of absorbed photons and, consequently, an increase in short-circuit current density (Jsc and cell efficiency. Through optical simulations, we recently obtained strong indications that texturing of the transparent conductor in copper indium gallium (di-selenide (CIGS solar cells is also optically advantageous. Here, we experimentally demonstrate that the Jsc and efficiency of CIGS solar cells with an absorber layer thickness (dCIGS of 0.85 μm, 1.00 μm and 2.00 μm increase through application of a moth-eye textured resist with a refractive index that is sufficiently similar to AZO (nresist = 1.792 vs. nAZO = 1.913 at 633 nm to avoid large optical losses at the resist-AZO interface. On average, Jsc increases by 7.2%, which matches the average reduction in reflection of 7.0%. The average relative increase in efficiency is slightly lower (6.0%. No trend towards a larger relative increase in Jsc with decreasing dCIGS was observed. Ergo, the increase in Jsc can be fully explained by the reduction in reflection, and we did not observe any increase in Jsc based on an increased photon path length.

  5. Ecotoxicological assessment of solar cell leachates: Copper indium gallium selenide (CIGS) cells show higher activity than organic photovoltaic (OPV) cells.

    Science.gov (United States)

    Brun, Nadja Rebecca; Wehrli, Bernhard; Fent, Karl

    2016-02-01

    Despite the increasing use of photovoltaics their potential environmental risks are poorly understood. Here, we compared ecotoxicological effects of two thin-film photovoltaics: established copper indium gallium selenide (CIGS) and organic photovoltaic (OPV) cells. Leachates were produced by exposing photovoltaics to UV light, physical damage, and exposure to environmentally relevant model waters, representing mesotrophic lake water, acidic rain, and seawater. CIGS cell leachates contained 583 μg L(-1) molybdenum at lake water, whereas at acidic rain and seawater conditions, iron, copper, zinc, molybdenum, cadmium, silver, and tin were present up to 7219 μg L(-1). From OPV, copper (14 μg L(-1)), zinc (87 μg L(-1)) and silver (78 μg L(-1)) leached. Zebrafish embryos were exposed until 120 h post-fertilization to these extracts. CIGS leachates produced under acidic rain, as well as CIGS and OPV leachates produced under seawater conditions resulted in a marked hatching delay and increase in heart edema. Depending on model water and solar cell, transcriptional alterations occurred in genes involved in oxidative stress (cat), hormonal activity (vtg1, ar), metallothionein (mt2), ER stress (bip, chop), and apoptosis (casp9). The effects were dependent on the concentrations of cationic metals in leachates. Addition of ethylenediaminetetraacetic acid protected zebrafish embryos from morphological and molecular effects. Our study suggests that metals leaching from damaged CIGS cells, may pose a potential environmental risk.

  6. Simulation of the Efficiency of CdS/CIGS Tandem Multi-Junction Solar Cells Using AMPS-1D

    CERN Document Server

    Mirkamali, Ashrafalsadat S

    2016-01-01

    In this paper we conduct numerical simulation of CdS/CIGS solar cells by use of the AMPS-1D software aiming to formulate the optimal design of the new multi-junction tandem solar cell providing its most efficient operation. We start with the numerical simulation of single-junction CdS/CIGS solar cells, which shows that its highest efficiency of 17.3% could be achieved by the thickness of CIGS p-layer of 200 nm. This result is in a good agreement with experimental data where the highest efficiency was 17.1% with the solar cell thickness of 1 micron. By use of the results of the numerical simulation of the single-junction solar cells we developed the design and conducted optimization of the new multi-junction tandem CdS/CIGS solar cell structure. Numerical simulation shows that the maximum efficiency of this solar cell is equal to 48.3%, which could be obtained with the thickness of the CIGS p-layer of 600 nm at a standard illumination of AM 1.5.

  7. Ecotoxicological assessment of solar cell leachates: Copper indium gallium selenide (CIGS) cells show higher activity than organic photovoltaic (OPV) cells.

    Science.gov (United States)

    Brun, Nadja Rebecca; Wehrli, Bernhard; Fent, Karl

    2016-02-01

    Despite the increasing use of photovoltaics their potential environmental risks are poorly understood. Here, we compared ecotoxicological effects of two thin-film photovoltaics: established copper indium gallium selenide (CIGS) and organic photovoltaic (OPV) cells. Leachates were produced by exposing photovoltaics to UV light, physical damage, and exposure to environmentally relevant model waters, representing mesotrophic lake water, acidic rain, and seawater. CIGS cell leachates contained 583 μg L(-1) molybdenum at lake water, whereas at acidic rain and seawater conditions, iron, copper, zinc, molybdenum, cadmium, silver, and tin were present up to 7219 μg L(-1). From OPV, copper (14 μg L(-1)), zinc (87 μg L(-1)) and silver (78 μg L(-1)) leached. Zebrafish embryos were exposed until 120 h post-fertilization to these extracts. CIGS leachates produced under acidic rain, as well as CIGS and OPV leachates produced under seawater conditions resulted in a marked hatching delay and increase in heart edema. Depending on model water and solar cell, transcriptional alterations occurred in genes involved in oxidative stress (cat), hormonal activity (vtg1, ar), metallothionein (mt2), ER stress (bip, chop), and apoptosis (casp9). The effects were dependent on the concentrations of cationic metals in leachates. Addition of ethylenediaminetetraacetic acid protected zebrafish embryos from morphological and molecular effects. Our study suggests that metals leaching from damaged CIGS cells, may pose a potential environmental risk. PMID:26615488

  8. Matemáticas y literatura de 0 a 3: Un cuento de cigüeñas

    Directory of Open Access Journals (Sweden)

    Gonzalo Flecha López

    2014-12-01

    Full Text Available A partir de los elementos del entorno próximo, tanto físico como cultural, podemos abordar conceptos matemáticos relacionados con la clasificación y con la formación de conjuntos. Utilizando como punto de partida los cuentos “El libro del otoño” y “Un cuento de cigüeñas”, vamos a tratar de realizar clasificaciones utilizando como base la formación de conceptos. Realizaremos, con los niños, agrupamientos sencillos mediante relaciones equivalencia. Mathematics and literature from zero to three: A tale of storks. From the elements of the surrounding environment both physical and cultural, we can deal with mathematical concepts related to classification and formation of sets. Using as a starting point the reading of “The book of autumn” and “A tale of storks”, we will try to make classifications using as base concept formation. We will make, with children, simple groupings using equivalence relations.

  9. Recent Progress in CIGS Thin Film Solar Cell Research at NREL: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Ramanathan, K.; Hasoon, F. S.; Al-Thani, H.; Alleman, J.; Keane, J.; Dolan, J.; Contreras, M. A.; Bhattacharya, R.; Noufi, R.

    2001-10-01

    Presented at the 2001 NCPV Program Review Meeting: This paper summarizes our work toward improving reproducibility in fabricating high efficiency absorbers and devices. This paper summarizes our work toward improving reproducibility in fabricating high efficiency absorbers and devices. This resulted in the fabrication of a CIGS cell with an efficiency of 21% under concentrated light. We compare devices fabricated with CdS and with Cd solution treatment alone. A high conversion efficiency of 15.7% is obtained with the latter, and we attribute this to the n-type doping afforded by Cd. The work is extended to absorbers provided by Siemens Solar Industries (SSI).

  10. The Effect of Sputtering Parameters on the Film Properties of Molybdenum Back Contact for CIGS Solar Cells

    Directory of Open Access Journals (Sweden)

    Peng-cheng Huang

    2013-01-01

    Full Text Available Molybdenum (Mo thin films are widely used as a back contact for CIGS-based solar cells. This paper determines the optimal settings for the sputtering parameters for an Mo thin film prepared on soda lime glass substrates, using direct current (dc magnetron sputtering, with a metal Mo target, in an argon gas environment. A Taguchi method with an L9 orthogonal array, the signal-to-noise ratio, and an analysis of variances is used to determine the performance characteristics of the coating operation. The main sputtering parameters, such as working pressure (mTorr, dc power (W, and substrate temperature (°C, are optimized with respect to the structural features, surface morphology, and electrical properties of the Mo films. An adhesive tape test is performed on each film to determine the adhesion strength of the films. The experimental results show that the working pressure has the dominant effect on electrical resistivity and reflectance. The intensity of the main peak (110 for the Mo film increases and the full width at half maximum decreases gradually as the sputtering power is increased. Additionally, the application of an Mo bilayer demonstrates good adherence and low resistivity.

  11. Nd:YAG laser annealing investigation of screen-printed CIGS layer on PET: Layer annealing method for photovoltaic cell fabrication process

    KAUST Repository

    Alsaggaf, Ahmed

    2014-06-01

    Cu(In, Ga)Se2 (CIGS) ink was formulated from CIGS powder, polyvinyl butyral PVB, terpineol and polyester/polyamine co-polymeric dispersant KD-1. Thin films with different thicknesses were deposited on PET substrate using screen-printing followed by heat treatment using a Nd:YAG laser. The structure and morphology of the heated thin films were studied. The characterization of the CIGS powder, ink, and film was done using TGA, SEM, FIB, EDS, and XRD. TGA analysis shows that the CIGS ink is drying at 200 °C, which is well below the decomposition temperature of the PET substrate. It was observed by SEM that 20 pulses of 532nm and 60 mJ/cm2 Nd:YAG laser annealing causes atomic diffusion on the near surface area. Furthermore, FIB cross section images were utilized to monitor the effect of laser annealing in the depth of the layer. Laser annealing effects were compared to as deposited layer using XRD in reference to CIGS powder. The measurement shows that crystallinity of deposited CIGS is retained while EDS quantification and atomic ratio result in gradual loss of selenium as laser energy increases. The laser parameters were tuned in an effort to utilize laser annealing of screen-printed CIGS layer as a layer annealing method for solar cell fabrication process.

  12. CIGS P1, P2, P3 Scribing Processes using a Pulse Programmable Industrial Fiber Laser: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Rekow, M.; Murison, R.; Panarello, T.; Dunsky, C.; Dinkel, C.; Nikumb, S.; Pern, F. J.; Mansfield, L.

    2010-10-01

    We describe a novel set of laser processes for the CIGS P1, P2 and P3 scribing steps, the development of which has been enabled by a unique pulse-programmable fiber laser. We find that the unique pulse control properties of this 1064 nm wavelength laser have significant effects on the material removal dynamics of the various film layers in the CIGS material system. In the case of the P2 and P3 processes, the shaped pulses create new laser/material interaction effects that permit the material to be cleanly and precisely removed with zero Heat Affected Zone (HAZ) at the edges of the scribe. The new P2 and P3 processes we describe demonstrate the first use of infrared nanosecond laser pulses that eliminate the HAZ and the consequent localized compositional changes in the CIGS absorber material that result in poor shunt resistance. SEM micrographs and EDX compositional scans are presented. For the P1 scribe, we process the bi-layer molybdenum from the film side as well as through the glass substrate. Microscopic inspection and compositional analysis of the scribe lines are not sufficient to determine electrical and optical performance in working PV modules. Therefore, to demonstrate the applicability of the infrared pulse-programmable laser to all three scribing processes for thin-film CIGS, we fabricate small-size multiple-cell monolithically interconnected mini-modules in partnership with the National Renewable Energy Laboratory (Golden, Colorado). A total of four mini-modules are produced, two utilizing all laser scribing, and two with the P2 and P3 steps mechanically scribed (by a third party) for reference. Mini-module performance data measured at NREL is presented, and we also discuss the commercialization potential of the new single-laser CIGS scribing process. Finally we present a phenomenological model to describe this physics underlying this novel ablation process.

  13. Efficiency enhancement in two-cell CIGS photovoltaic system with low-cost optical spectral splitter.

    Science.gov (United States)

    Maragliano, Carlo; Apostoleris, Harry; Bronzoni, Matteo; Rampino, Stefano; Stefancich, Marco; Chiesa, Matteo

    2016-01-25

    Spectrum splitting represents a valid alternative to multi-junction solar cells for broadband light-to-electricity conversion. While this concept has existed for decades, its adoption at the industrial scale is still stifled by high manufacturing costs and inability to scale to large areas. Here we report the experimental validation of a novel design that could allow the widespread adoption of spectrum splitting as a low-cost approach to high efficiency photovoltaic conversion. Our system consists of a prismatic lens that can be manufactured using the same methods employed for conventional CPV optic production, and two inexpensive CuInGaSe(2) (CIGS) solar cells having different composition and, thus, band gaps. We demonstrate a large improvement in cell efficiency under the splitter and show how this can lead to substantial increases in system output at competitive cost using existing technologies. PMID:26832577

  14. Semi-transparent perovskite solar cells for tandems with silicon and CIGS

    KAUST Repository

    Bailie, Colin D.

    2015-01-01

    © 2015 The Royal Society of Chemistry. A promising approach for upgrading the performance of an established low-bandgap solar technology without adding much cost is to deposit a high bandgap polycrystalline semiconductor on top to make a tandem solar cell. We use a transparent silver nanowire electrode on perovskite solar cells to achieve a semi-transparent device. We place the semi-transparent cell in a mechanically-stacked tandem configuration onto copper indium gallium diselenide (CIGS) and low-quality multicrystalline silicon (Si) to achieve solid-state polycrystalline tandem solar cells with a net improvement in efficiency over the bottom cell alone. This work paves the way for integrating perovskites into a low-cost and high-efficiency (>25%) tandem cell.

  15. Uniform, High Efficiency, Hybrid CIGS Process with Application to Novel Device Structures: Annual Technical Report, 15 March 2005 - 14 March 2006

    Energy Technology Data Exchange (ETDEWEB)

    Delahoy, A. E.; Chen, L.; Sang, B.

    2006-06-01

    One of the main Phase I objectives of this subcontract was for EPV to demonstrate 14%-efficient CIGS devices using a hybrid process. The processing was also required to have good control ability. These goals were successfully accomplished. It will be seen that during Phase I, we successfully developed a new, simplified hybrid process. A highlight of intensive work was the achievement of a 14.0% NREL-verified device at a CIGS thickness of 1.13 ..mu..m. The simplified hybrid process considerably reduces CIGS film formation time and offers the promise of being a truly cost-effective and manufacturable one. It is considered to be one of the more attractive CIGS processes in the industry.

  16. Notas sobre Feral y las cigüeñas, de Fernando Alonso, y la "Historia del califa cigüeña" (Wilhelm Hauff, Sara Cone Bryant

    Directory of Open Access Journals (Sweden)

    Hans Christian Hagedorn

    2011-01-01

    Full Text Available En el presente estudio se analizan las fuentes de la versión de la "Historia del califa cigüeña", incluida en la narración Feral y las cigüeñas (1971, de Fernando Alonso. Para ello se tienen en cuenta el cuento original del autor postromántico alemán Wilhelm Hauff ("Die Geschichte von Kalif Storch", 1825, y la adaptación de este cuento que Sara Cone Bryant realizó para su libro How to tell stories to children (1905, traducción española: El arte de contar cuentos, 1965.

  17. Stability of CIGS solar cells and component materials evaluated by a step-stress accelerated degradation test method

    Science.gov (United States)

    Pern, F. J.; Noufi, R.

    2012-10-01

    A step-stress accelerated degradation testing (SSADT) method was employed for the first time to evaluate the stability of CuInGaSe2 (CIGS) solar cells and device component materials in four Al-framed test structures encapsulated with an edge sealant and three kinds of backsheet or moisture barrier film for moisture ingress control. The SSADT exposure used a 15°C and then a 15% relative humidity (RH) increment step, beginning from 40°C/40%RH (T/RH = 40/40) to 85°C/70%RH (85/70) as of the moment. The voluminous data acquired and processed as of total DH = 3956 h with 85/70 = 704 h produced the following results. The best CIGS solar cells in sample Set-1 with a moisture-permeable TPT backsheet showed essentially identical I-V degradation trend regardless of the Al-doped ZnO (AZO) layer thickness ranging from standard 0.12 μm to 0.50 μm on the cells. No clear "stepwise" feature in the I-V parameter degradation curves corresponding to the SSADT T/RH/time profile was observed. Irregularity in I-V performance degradation pattern was observed with some cells showing early degradation at low T/RH = 70/70. Results of (electrochemical) impedance spectroscopy (ECIS) analysis indicate degradation of the CIGS solar cells corresponded to increased series resistance Rs (ohm) and degraded parallel (minority carrier diffusion/recombination) resistance Rp, capacitance C, overall time constant Rp*C, and "capacitor quality" factor (CPE-P), which were related to the cells' p-n junction properties. Heating at 85/70 appeared to benefit the CIGS solar cells as indicated by the largely recovered CPE-P factor. Device component materials, Mo on soda lime glass (Mo/SLG), bilayer ZnO (BZO), AlNi grid contact, and CdS/CIGS/Mo/SLG in test structures with TPT showed notable to significant degradation at T/RH >= 70/70. At T/RH = 85/70, substantial blistering of BZO layers on CIGS cell pieces was observed that was not seen on BZO/glass, and a CdS/CIGS sample displayed a small darkening and then

  18. Stability of CIGS Solar Cells and Component Materials Evaluated by a Step-Stress Accelerated Degradation Test Method: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Pern, F. J.; Noufi, R.

    2012-10-01

    A step-stress accelerated degradation testing (SSADT) method was employed for the first time to evaluate the stability of CuInGaSe2 (CIGS) solar cells and device component materials in four Al-framed test structures encapsulated with an edge sealant and three kinds of backsheet or moisture barrier film for moisture ingress control. The SSADT exposure used a 15oC and then a 15% relative humidity (RH) increment step, beginning from 40oC/40%RH (T/RH = 40/40) to 85oC/70%RH (85/70) as of the moment. The voluminous data acquired and processed as of total DH = 3956 h with 85/70 = 704 h produced the following results. The best CIGS solar cells in sample Set-1 with a moisture-permeable TPT backsheet showed essentially identical I-V degradation trend regardless of the Al-doped ZnO (AZO) layer thickness ranging from standard 0.12 μm to 0.50 μm on the cells. No clear 'stepwise' feature in the I-V parameter degradation curves corresponding to the SSADT T/RH/time profile was observed. Irregularity in I-V performance degradation pattern was observed with some cells showing early degradation at low T/RH < 55/55 and some showing large Voc, FF, and efficiency degradation due to increased series Rs (ohm-cm2) at T/RH ≥ 70/70. Results of (electrochemical) impedance spectroscopy (ECIS) analysis indicate degradation of the CIGS solar cells corresponded to increased series resistance Rs (ohm) and degraded parallel (minority carrier diffusion/recombination) resistance Rp, capacitance C, overall time constant Rp*C, and 'capacitor quality' factor (CPE-P), which were related to the cells? p-n junction properties. Heating at 85/70 appeared to benefit the CIGS solar cells as indicated by the largely recovered CPE-P factor. Device component materials, Mo on soda lime glass (Mo/SLG), bilayer ZnO (BZO), AlNi grid contact, and CdS/CIGS/Mo/SLG in test structures with TPT showed notable to significant degradation at T/RH ≥ 70/70. At T/RH = 85/70, substantial blistering of

  19. Simulation Study of Effects, Operating Temperature and Layer Thickness on Thin Film CIGS Solar Cell Performance

    Directory of Open Access Journals (Sweden)

    A.D. Pogrebnjak

    2011-01-01

    Full Text Available SCAPS- program is designed basically for the simulation and studying the properties of photonic devices. We explored the important controllable design parameters affecting the performance of the hetero junction solar cells, as operating temperature that we noticed increasing in J-V characteristics by increasing T, the effect of thickness of each layer on the performance of the cell was studied, an increasing of J-V characteristics with increasing p-layer , In the numerical example, 3 μm absorber layer and CdS layer 0.05 μm, ZnO layer 0.1 μm, works the best for given doping density, if we change the optimum value , the efficiency can reach to 17.72 % with FF 83.88 %, Voc = 0.725 Volt, Jsc = 29.07 mA/cm2 at 300 K, in this case, we have come out the optimum parameters to achieve the best performance of this type of cell, and then to made comparison with practical CIGS cell.

  20. Improving Performance of CIGS Solar Cells by Annealing ITO Thin Films Electrodes

    Directory of Open Access Journals (Sweden)

    Chuan Lung Chuang

    2015-01-01

    Full Text Available Indium tin oxide (ITO thin films were grown on glass substrates by direct current (DC reactive magnetron sputtering at room temperature. Annealing at the optimal temperature can considerably improve the composition, structure, optical properties, and electrical properties of the ITO film. An ITO sample with a favorable crystalline structure was obtained by annealing in fixed oxygen/argon ratio of 0.03 at 400°C for 30 min. The carrier concentration, mobility, resistivity, band gap, transmission in the visible-light region, and transmission in the near-IR regions of the ITO sample were -1.6E+20 cm−3, 2.7E+01 cm2/Vs, 1.4E-03 Ohm-cm, 3.2 eV, 89.1%, and 94.7%, respectively. Thus, annealing improved the average transmissions (400–1200 nm of the ITO film by 16.36%. Moreover, annealing a copper-indium-gallium-diselenide (CIGS solar cell at 400°C for 30 min in air improved its efficiency by 18.75%. The characteristics of annealing ITO films importantly affect the structural, morphological, electrical, and optical properties of ITO films that are used in solar cells.

  1. Effect of electrodeposition potential on composition and morphology of CIGS absorber thin film

    Indian Academy of Sciences (India)

    N D Sang; P H Quang; L T Tu; D T B Hop

    2013-08-01

    CuInGaSe (CIGS) thin films were deposited on Mo/soda-lime glass substrates by electrodeposition at different potentials ranging from −0.3 to −1.1 V vs Ag/AgCl. Cyclic voltammetry (CV) studies of unitary Cu, Ga, In and Se systems, binary Cu–Se, Ga–Se and In–Se systems and quaternary Cu–In–Ga–Se were carried out to understand the mechanism of deposition of each constituent. Concentration of the films was determined by energy dispersive spectroscopy. Structure and morphology of the films were characterized by X-ray diffraction and scanning electron microscope. The underpotential deposition mechanism of Cu–Se and In–Se phases was observed in voltammograms of binary and quaternary systems. Variation in composition with applied potentials was explained by cyclic voltammetry (CV) data. A suitable potential range from −0.8 to −1.0 V was found for obtaining films with desired and stable stoichiometry. In the post-annealing films, chalcopyrite structure starts forming in the samples deposited at −0.5 V and grows on varying the applied potential towards negative direction. By adjusting the composition of electrolyte, we obtained the desired stoichiometry of Cu(In0.7Ga0.3)Se2.

  2. Examination of Na-Doped Mo Sputtering for CIGS Devices: Cooperative Research and Development Final Report, CRADA Number CRD-10-375

    Energy Technology Data Exchange (ETDEWEB)

    Repins, I.

    2012-01-01

    This work has investigated the use of Na doped Mo (MONA) sputtering targets for use in preparing CIGS devices. The Mo:Na material is doped to about 3% Na by weight, implying that a 40 nm layer on top of the standard Mo contact contains sufficient Na to dope a 2.5 ..mu..m CIGS film. The ability to control Na doping independent of both CIGS processing conditions and adhesion is an important gain for industry and research. Manufacturers gain a route to increased manufacturability and performance, while NREL researchers gain a tightened performance distribution of devices and increased process flexibility. Our immediate partner in this work, the Climax Molybdenum Technology Center, gains validation of their product.

  3. Flexible CIGS solar cells on large area polymer foils with in-line deposition methods and application of alternative back contacts - Final report

    Energy Technology Data Exchange (ETDEWEB)

    Tiwari, A. N.

    2009-08-15

    This illustrated report for the Swiss Federal Office of Energy (SFOE) summarises the work performed within this project and also reports on synergies with other projects that helped to make a significant contribution to the development of CIGS thin film solar cells on flexible substrates such as polymer foils. The project's aims were to learn more about up-scaling issues and to demonstrate the abilities required for the processing of layers on large area polyimide foils for flexible CIGS solar cells. Custom-built evaporators that were designed and constructed in-house are described. A CIGS system for in-line deposition was also modified for roll-to-roll deposition and alternative electrical back contacts to conventional ones were evaluated on flexible polyimide foils. The objectives of the project and the results obtained are looked at and commented on in detail.

  4. La cigüeña en las literaturas populares francesa y española

    OpenAIRE

    Sevilla Muñoz, Julia

    2007-01-01

    Estudio de la presencia de la cigüeña en varios géneros de las literaturas populares francesa y española (fábulas, coplas, adivinanzas, refranes), con el objeto de descubrir las peculiaridades y la simbología de este animal, así como la cultura popular que ha servido de fuente de inspiración. Study of the presence of stork in several of the genres in French and Spanish popular literatures (fables, songs, riddles, proverbs) in order to show up the particular characteristics and the symbols ...

  5. Primera cita de reproducción de cigüeñuela común Himantopus himantopus L., 1758 en Urdaibai (Bizkaia

    Directory of Open Access Journals (Sweden)

    ARIZAGA, J., AZKONA, A., CEPEDA, X., MAGUREGI, J., UNAMUNO, E., UNAMUNO, J.M.

    2012-01-01

    Full Text Available La colonización del Cantábrico por la cigüeñuela común Himantopus himantopus L., 1758 es un fenómeno reciente (se cita por primera vez en 2009 en Asturias y Cantabria. En 2012, y por primera vez para Urdaibai y la costa vasca, se constata la reproducción de cigüeñuela en la laguna de Orueta, en el municipio de Gautegiz-Arteaga (Bizkaia. En particular, una pareja fue capaz de sacar adelante 3 pollos.

  6. RESEARCH ON CIS AND CIGS THIN FILM SOLAR CELLS%CIS和CIGS薄膜太阳电池的研究

    Institute of Scientific and Technical Information of China (English)

    孙云; 王俊清; 杜兆峰; 舒保健; 于刚; 温国忠; 周祯华; 孙健; 李长健; 张丽珠

    2001-01-01

    P type CIS and CIGS thin films are fabricated by evaporating selenylation method,and so are N type CdS.They compose heterogeneity PN junction solar cells.After annealing,the cells'efficiencies reach 8.83%and 9.13% respectively.CIS Fabricating technology and key problems are discussed.The opinions about annealing are given in this article.%采用蒸发硒化方法制备了P型CIS(铜铟硒)和CIGS(铜铟镓硒)薄膜,用蒸发法制备N型CdS(硫化镉),二者组成异质PN结太阳电池。经退火处理,CIS和CIGS薄膜太阳电池的效率分别达到8.83%和9.13%。对制膜过程中衬底的选择,背电极的制备,CIS各元素蒸发控制和镓的掺入等工艺技术问题进行了深入的讨论,对电池的退火处理提出了自己的见解。

  7. Photoelectrochemical water splitting for hydrogen production using combination of CIGS2 solar cell and RuO2 photocatalyst

    International Nuclear Information System (INIS)

    This paper presents the development of photoelectrochemical (PEC) cell for water splitting setup using multiple band gap combination of CuIn1-xGa xS2 (CIGS2) thin-film photovoltaic (PV) cell and ruthenium oxide (RuO2) photocatalyst. FSEC PV Materials Lab has developed a PEC setup consisting of two illuminated CIGS2 cells, a ruthenium oxide (RuO2) anode deposited on titanium sheet for oxygen evolution and a platinum foil cathode for hydrogen evolution. With this combination, a PEC efficiency of 4.29% has been achieved. This paper also presents the research aimed at further improvements in the PEC efficiency by employing highly efficient photoanode that can be illuminated by photons not absorbed at the PV cell and by increasing the concentration of electrolyte solution (pH 10). The former will be achieved by employing a p-type transparent and conducting layer at the back of PV cell to transmit the unabsorbed photons, and the latter will reduce the resistance offered by the electrolyte. Concentration of the electrolyte was increased by five times, and the I-V characteristics of both RuO2 and RuS2 were measured with and without illumination. The results indicate that PEC efficiencies of over 9% can be achieved using RuS2 with illumination and five times concentrated pH 10 solution instead of pH 10 with normal concentration

  8. Investigation of an Electrochemical Method for Separation of Copper, Indium, and Gallium from Pretreated CIGS Solar Cell Waste Materials

    Directory of Open Access Journals (Sweden)

    Anna M. K. Gustafsson

    2015-01-01

    Full Text Available Recycling of the semiconductor material copper indium gallium diselenide (CIGS is important to ensure a future supply of indium and gallium, which are relatively rare and therefore expensive elements. As a continuation of our previous work, where we recycled high purity selenium from CIGS waste materials, we now show that copper and indium can be recycled by electrodeposition from hydrochloric acid solutions of dissolved selenium-depleted material. Suitable potentials for the reduction of copper and indium were determined to be −0.5 V and −0.9 V (versus the Ag/AgCl reference electrode, respectively, using cyclic voltammetry. Electrodeposition of first copper and then indium from a solution containing the dissolved residue from the selenium separation and ammonium chloride in 1 M HCl gave a copper yield of 100.1 ± 0.5% and an indium yield of 98.1 ± 2.5%. The separated copper and indium fractions contained no significant contamination of the other elements. Gallium remained in solution together with a small amount of indium after the separation of copper and indium and has to be recovered by an alternative method since electrowinning from the chloride-rich acid solution was not effective.

  9. Effect of deposition pressure on the properties of magnetron-sputter-deposited molybdenum back contacts for CIGS solar cells

    Science.gov (United States)

    Li, Weimin; Yan, Xia; Aberle, Armin G.; Venkataraj, Selvaraj

    2015-08-01

    Molybdenum (Mo) thin films were deposited onto soda-lime glass substrates by DC magnetron sputtering of a Mo target at various chamber pressures ranging from 1.5 × 10-3 to 7.5 × 10-3 mbar. The film properties were analysed with regards to their application as back electrode in copper indium gallium diselenide (CIGS) solar cells. It is observed that the resulting film morphology and microstructure were strongly affected by deposition pressure. Mo films deposited at a low pressure possess a high density and a low sheet resistance. These films also have a compact microstructure and a compressive strain, which lead to poor adhesion. The adhesion can be improved by increasing the chamber pressure, which has negative effects on the sheet resistance, optical reflection and porosity of the films. On the basis of these results, a method has been established to fabricate low-resistivity Mo films on soda-lime glass with very good adhesion for CIGS solar cell applications.

  10. Fabrication of chalcopyrite light-absorbing layers based on nanoparticle and nanowire networks

    Science.gov (United States)

    Ren, Yuhang; Luo, Paifeng; Gao, Bo; Cevher, Zehra; Sun, Chivin

    2013-03-01

    We report on a method of preparing chalcopyrite, CuInGaSe2 (CIGS) light-absorbing layers using low cost air stable ink based on semiconductor nanoparticle and nanowires. The nanoparticles and nanowires are prepared from metal salts such as metal chloride and acetate at room temperature without inert gas protection. A uniform and non-aggregation CIGS precursor layer is fabricated with the formation of nanoparticle and nanowire networks utilizing ultrasonic spaying technique. We obtain a high quality CIGS absorber by cleaning the residue salts and carbon agents at an increased temperature and through selenizing the pretreated CIGS precursors. Our results offer an opportunity for the low-cost deposition of chalcopyrite absorber materials at large scale with high throughput. This work was partially sponsored by Sun Harmonics Ltd. and by NYSTAR through the Photonics Center for Applied Technology at the City University of New York.

  11. High-temperature stability of molybdenum (Mo) back contacts for CIGS solar cells: a route towards more robust back contacts

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Ju-Heon; Yoon, Kwan-Hee; Jeong, Jeung-hyun [Solar Cell Research Center, Korea Institute of Science and Technology, 39-1, Seoul 136-791 (Korea, Republic of); Kim, Won Mok; Park, Jong-Keuk; Baik, Young-Joon [Electronic Materials Research Center, Korea Institute of Science and Technology, 39-1, Seoul 136-791 (Korea, Republic of); Seong, Tae-Yeon, E-mail: jhjeong@kist.re.kr [Department of Materials Science and Engineering, College of Engineering, Korea University, Seoul 136-701 (Korea, Republic of)

    2011-10-26

    The thermal stability of Mo thin films is indispensable to Cu(In,Ga)Se{sub 2} (CIGS) solar cells: CIGS films are deposited above 500 deg. C. The thermal stabilities of Mo thin films with dense to porous Mo microstructures, which are varied by controlling the sputtering pressure, are investigated. Interface failures are found to occur in buckling mode in denser Mo films, whereas cracking arises in less dense films. The failure modes are apparently dependent on the sign of the residual stress: the former is due to compressive stress, whereas the latter is due to tensile stress. Interestingly, the softening of soda-lime glass at high temperatures reconfigures the film stresses to be more compressive after annealing, which in turn triggers buckling even in films that are tensile-stressed in the as-deposited states. We conclude that the appropriate processing conditions for thermally stable back contacts cannot be obtained with the simple single layer approach. On the basis of this relationship between microstructure, residual stress and the failure modes, it is shown that improvements in film adhesion can widen the processing window for the preparation of robust back contacts, i.e. with a conventional bilayer approach and substrate roughening. Since the bilayer approach employed more compliant porous structures in the bottom layer, back contacts that are better suited to higher stress and temperature can be produced. Furthermore, substrate roughening might make the back contact more conductive as well as more stable because adhesion can be enhanced without the use of an electrically resistive buffer layer.

  12. Effector Protein Cig2 Decreases Host Tolerance of Infection by Directing Constitutive Fusion of Autophagosomes with the Coxiella-Containing Vacuole

    Directory of Open Access Journals (Sweden)

    Lara J. Kohler

    2016-07-01

    Full Text Available Coxiella burnetii replicates in an acidified lysosome-derived vacuole. Biogenesis of the Coxiella-containing vacuole (CCV requires bacterial effector proteins delivered into host cells by the Dot/Icm secretion system. Genetic and cell biological analysis revealed that an effector protein called Cig2 promotes constitutive fusion of autophagosomes with the CCV to maintain this compartment in an autolysosomal stage of maturation. This distinguishes the CCV from other pathogen-containing vacuoles that are targeted by the host autophagy pathway, which typically confers host resistance to infection by delivering the pathogen to a toxic lysosomal environment. By maintaining the CCV in an autolysosomal stage of maturation, Cig2 enabled CCV homotypic fusion and enhanced bacterial virulence in the Galleria mellonella (wax moth model of infection by a mechanism that decreases host tolerance. Thus, C. burnetii residence in an autolysosomal organelle alters host tolerance of infection, which indicates that Cig2-dependent manipulation of a lysosome-derived vacuole influences the host response to infection.

  13. Distortions to current-voltage curves of cigs cells with sputtered Zinc(Oxygen,Sulfur) buffer layers

    Science.gov (United States)

    Song, Tao

    Sputtered-deposited Zn(O,S) is an attractive alternative to CdS for Cu(In,Ga)Se 2 (CIGS) thin-film solar cells' buffer layer. It has a higher band gap and thus allows greater blue photon collection to achieve higher photon current. The primary goal of the thesis is to investigate the effects of the secondary barrier at the buffer-absorber interface on the distortions to current-voltage (J-V) curves of sputtered-Zn(O,S)/CIGS solar cells. A straightforward photodiode model is employed in the numerical simulation to explain the physical mechanisms of the experimental J-V distortions including J-V crossover and red kink. It is shown that the secondary barrier is influenced by both the internal material properties, such as the conduction-band offset (CBO) and the doping density of Zn(O,S), and the external conditions, such as the light intensity and operating temperature. A key parameter for the sputter deposition of Zn(O,S) has been the oxygen fraction in the argon beam. It is found that the CBO varies with the oxygen fraction in the argon beam at a fixed temperature. With a greater CBO (DeltaEC>0.3 eV), the resulting energy barrier limits the electron current flowing across the interface and thus leads to the J-V distortion. Two different ZnS targets, non-indium and indium-doped one, were used to deposit the Zn(O,S) buffer layer. At the same oxygen fraction in argon beam, a non-In-doped Zn(O,S) buffer with a smaller amount of doping forms a greater secondary barrier to limit the electron current due to the compensation of the Zn(O,S) buffer layer. In addition, the temperature-dependent J-V crossover can be explained by the temperature-dependent impact of the secondary barrier - at lower temperature in the dark, the maximum distortion-free barrier is reduced and results in a more serious current limitation, indicating a greater J-V crossover. It is also found that, under low-intensity illumination, there is a lower doping density of Zn(O,S) due to a smaller amount of

  14. Second-hand smoke exposure generated by new electronic devices (IQOS® and e-cigs) and traditional cigarettes: submicron particle behaviour in human respiratory system.

    Science.gov (United States)

    Protano, C; Manigrasso, M; Avino, P; Sernia, S; Vitali, M

    2016-01-01

    Passive exposure profiles to submicronic particles (SMPs, 5.6-560 nm) of traditional cigarettes and new electronic commercial devices (e-cig and IQOS®, a new heat-not-burn smoking device) were compared. During smoking, SMPs released by traditional cigarettes resulted four-times higher than those released by electronic and heat-not-burn devices and remained high for at least one hour, while SMPs values returned immediately similar to background for electronic and heat-not-burn devices. In all experiments, approximately half of SMPs resulted so small to reach the alveolar region. PMID:27071321

  15. Effect of Se Vapor Concentration on CIGS Film Preparation%硒蒸气浓度对制备CIGS薄膜的影响

    Institute of Scientific and Technical Information of China (English)

    廖成; 韩俊峰; 江涛; 谢华木; 焦飞; 赵夔

    2011-01-01

    We applied the “selenization of stack element layers” method to the preparation of CuIn1-xGaxSe2 (CIGS) films.The selenium vapor concentration was precisely controlled to optimize the annealing process using a homemade bilayer tubular selenization facility, and its effect on the photoelectric characteristics of the films was studied.Auger electron spectroscopy (AES) and X-ray diffraction (XRD) were used to analyze the composition distribution in the cross-section and to obtain phase information, respectively.The output performance of the CIGS device was also measured under AM1.5 1000 W·m-2 illumination.The results indicated that the molybdenum back contact layer was seriously degraded by the saturated selenium vapor during annealing.Annealing with a low concentration of selenium vapor led to bad performance because of segregation and defects in the film.The CIGS film was homogeneous after annealing in a selenium-free inert atmosphere and a conversion efficiency of 8.5% was obtained.%采用"预制层硒化法"制备Culn1-xGaxSe2(CIGS)薄膜,基于自主设计的"双层管式硒化装置",通过控制硒蒸气浓度优化退火工艺,研究硒蒸气浓度对薄膜光电性能的影响,利用俄歇电子能谱(AES)和X射线衍射分析(XRD)等手段对不同硒浓度氛围下生成的CIGS薄膜的成分和物相进行表征,并在AM1.5、1000 W·m-2的标准光照条件下比较相应CIGS电池器件的输出性能,实验结果表明:饱和硒蒸气下退火得到的样品,基底钼膜遭到严重腐蚀破坏,失去背电极功能;在低浓度硒气氛下退火不能有效消除CIGS薄膜的偏析和缺陷,以致光电转换效率低;而在无硒惰性氛围下退火的样品,生成了物相均一化的CIGS薄膜,由此制备的CIGS电池取得了8.5%的转换效率.

  16. Metodología para el estudio de las causas de rotura de cigüeñales en motores de combustión interna alternativos y compresores alternativos. Aplicación en un modelo de mantenimiento predictivo

    OpenAIRE

    Becerra Villanueva, José Antonio

    2007-01-01

    Los ejes cigüeñales son una parte fundamental en el funcionamiento de los motores de combustión interna alternativos y compresores volumétricos alternativos. El fallo de un cigüeñal no es uno de los problemas más frecuentes, sin embargo puede tener consecuencias muy importantes tanto en la integridad del sistema como en la disponibilidad de este, siendo además los costes asociados a su reparación, agravados por su difícil accesibilidad. En el diseño de cigüeñales el principal factor deter...

  17. "This I Suffered in the Short Space of my Life". The Epitaph for Lucius Minicius Anthimianus (CIG 3272; Peek GVn 1166).

    Science.gov (United States)

    Graumann, Lutz A; Horstmanshoff, Manfred

    2016-01-01

    Herewith we present an interdisciplinary study of the metrical funerary inscription from the third century CE (CIG 3272; Peek GV 1166). This emotional Greek epitaph reports the short life (from birth to death) of the 4 year old Lucius Minicius Anthimianus. This is the first detailed study since the dissertation by Klitsch (1976). The inscription presents an ideal case for a truly interdisciplinary study of the patient-history, in that its interpretation involves the study of Greek literature and linguistics, epigraphy, social and religious history, and ancient medicine. It also offers ample opportunity to show the contradictions inherent in proposing retrospective diagnosis, without neglecting the relevant information modern medicine has to offer for the interpretation of this case history. We argue that Lucius' father was most probably a physician, that the text of the inscription stems from expert knowledge of ancient medicine and that the traditional retrospective diagnosis of this case, tuberculosis, is an untenable hypothesis. PMID:26946673

  18. Influencia de la maduración del fruto de Arbutus xalapensis Kunth sobre la germinación de semillas y embriones cigóticos

    Directory of Open Access Journals (Sweden)

    Violeta Tovar-Rocha

    2015-07-01

    Full Text Available En este trabajo se determinó el efecto del estado de maduración del fruto en la germinación in vitro de semillas y embriones cigóticos deArbutus xalapensisKunt. Se colectaron frutos de 10 árboles en cada uno de los dos sitios de estudio y se clasifi caron según su tamaño y peso dentro de tres grupos caracterizados por el color del fruto: 1 a 6 frutos verde oscuro (FVO, 7 y 8 frutos verde-amarillo (FVA, y 9 y 10 frutos naranja-rojizo (FNR. De cada estado se seleccionaron 50 semillas y se colocaron en medio MS para evaluar su germinación. El experimento se repitió dos veces y los resultados obtenidos fueron sometidos a un análisis de comparación de medias de Tukey el cual indicó que los tres grupos de frutos presentan características de peso fresco y diámetro diferentes (P = 0.05, con un promedio de 6.3 g y de 0.21 mm para FVO, 9.5 g y 0.46 mm para FVA y 10.8 g y 0.70 mm para FNR. El análisis de microscopía estereoscópica demostró que todos los estados de maduración presentan semillas y embriones; los estados 1 al 4 presentan embriones no desarrollados, y en los estados 5 al 10 los frutos contienen un mayor número de semillas con embriones desarrollados y con una mayor germinación (7.6 a 8.8 semillas/unidad experimental. Se propone el uso de semillas provenientes de frutos de los estados de maduración 5 al 10 para la germinación adecuada de semillas de madroño, mientras que para los embriones cigóticos es necesario realizar estudios de prueba de medios de cultivo para su germinación.

  19. Research Progress on Buffer Layer Materials of CIGS Thin Film Solar Cell%CIGS薄膜太阳能电池缓冲层材料的研究进展

    Institute of Scientific and Technical Information of China (English)

    王卫兵; 刘平; 李伟; 马凤仓; 刘新宽; 陈小红

    2012-01-01

    CIGS薄膜太阳能电池的缓冲层为低带隙CIGS吸收层与高带隙ZnO窗口层之间形成过渡,减少两者带隙的晶格失配和带隙失调,并可防止溅射ZnO窗口层时给CIGS吸收层带来损害等,对提高CIGS薄膜太阳能电池效率起了重要作用.介绍了CIGS薄膜太阳能电池缓冲层材料的分类和制备工艺,主要阐述了CdS、ZnS及In2S3薄膜缓冲层材料及化学水浴法、原子层化学气相沉积法、金属化合物化学气相沉积法等制备工艺的研究现状,最后指出CIGS太阳能电池缓冲层在制备工艺、环境保护及大规模工业化生产中遇到的问题,并展望了其发展方向.%The buffer layers of CTGS thin film solar cells can form transition layers between low band gap CIGS absorber layers and high band gap of ZnO window layers, which reduces the lattice matching and band gap difference, and prevents damage of CIGS absorber layer from sputtering ZnO window layer, and therefore plays an important role in improving efficiency of CIGS thin film solar cells. Classification and preparation technology of CIGS thim film solar cells material are discussed, including the research progress of CdS,ZnS and In2S3 thin film buffer layer materials, and chemical bath deposition (CBD), atomic layer chemical vapor deposition (ALCVD), metal organic chemical vapor deposition (MOCVD) and other preparation technologies. The problems and development directions of buffer layer materials of CIGS thin film solar cells in preparation process, environment protection and large-scale industrial production are finally prospected.

  20. Study of the recombination process at crystallite boundaries in CuIn{sub 1-x}Ga{sub x}Se{sub 2} (CIGS) films by microwave photoconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Bocharov, K. V.; Novikov, G. F., E-mail: gfnovikov@gmail.com [Russian Academy of Sciences, Institute of Problems of Chemical Physics (Russian Federation); Hsieh, T. Y. [Chang-Gung University, Department of Electronic Engineering and Green Technology Research Center (China); Gapanovich, M. V. [Russian Academy of Sciences, Institute of Problems of Chemical Physics (Russian Federation); Jeng, M. J. [Chang-Gung University, Department of Electronic Engineering and Green Technology Research Center (China)

    2013-03-15

    The loss kinetics of photogenerated charge carriers in thin polycrystalline chalcopyrite CuIn{sub 1-x}Ga{sub x}Se{sub 2} (CIGS) films has been studied by microwave photoconductivity (at 36 GHz). The films were synthesized using the ampoule method and three variants of physical vapor deposition with subsequent selenization: magnetron sputtering, thermal deposition, and modified thermal deposition with intermetallic precursors. The photoconductivity was excited by 8-ns nitrogen laser pulses with maximum intensity of 4 Multiplication-Sign 10{sup 14} photons/cm per pulse. Measurements were performed in the temperature range 148-293 K. The photoresponse amplitude is found to depend linearly on the sizes of coherent-scattering regions in the film grains, which were calculated from X-ray diffraction data. The photoresponse decay obeys hyperbolic law. The photoresponse half-decay time increases with a decrease in both temperature and light intensity. It is shown that the recombination of free holes with trapped electrons is very efficient near the crystallite boundaries.

  1. Zn1-xMgxO用于CIGS太阳电池的研究进展%Developments of CIGS Solar Cells with Zn1-xMgxO Films

    Institute of Scientific and Technical Information of China (English)

    江秋怡; 王卿璞; 王汉斌; 王丹丹; 武丽伟; 李福杰

    2013-01-01

    Zn1-xMgxO透过率高、带隙可调,且与CIGS太阳电池在晶格和能带结构上匹配良好,可用作CIGS太阳电池缓冲层、窗口层,因此制备高质量的Zn1-xMgxO薄膜是提高太阳电池性能的关键.文章介绍了Zn1-xMgxO薄膜的结构特性、光学特性及制备方法;从Mg含量、Zn1-xMgxO膜厚及Zn1-xMgxO/CIGS界面处缺陷密度等方面概述了Zn1-xMgxO用于CIGS太阳电池的研究进展,并比较了Zn1-xMgxO与In2S3,ZnS,CdS等其他材料作缓冲层的CIGS太阳电池性能的差别.%With high transparency,adjustable band gap and good match with CIGS in lattice and energy band structure,Zn1-xMgxO is regarded as the suitable material for the buffer layer and window layer of CIGS solar cells,so the fabrication of high quality Zn1-xMgxO films becomes to be the key problem for improving the efficiency of CIGS solar cells.In this paper,the preparation methods and structural and optical characteristics of Zn1-xMgxO films are introduced;and also the effects of concentration of Mg,the film thickness and the defect density on solar cells are summarized.As well it is compared the performance of solar cells with Zn1-xMgxO buffer layer with those applying other buffer layer materials.

  2. Analysis of Effects Resulted from Changing the Buffer Layer Material on Optimization of Cu (In 1-x,Gax Se2 Thin Filmsolar cell(CIGS and Simulation of Cell Structure

    Directory of Open Access Journals (Sweden)

    Nafise Shams

    2013-12-01

    Full Text Available Due tothe present globalunderstandingabout utilization ofrenewable energysources as constantcleanones, PVpowerhas beenthefocused bymanyresearch centers. Research of developmentofPhotovoltaic Energyis generally done in tow fields:reducingcosts andincreasing efficiency. CIGS thin film solar cells are of particular importance among the other types of the same category, due to the flexibility and yields of about 20%.Thispaper examines theperformance ofnanostructuredCIGSsolarcellsare discussed. The impact of changing material in the buffer layer of cell structure on electrical properties and the overall performance is evaluated. The optimized efficiency is also determined using simulation tools.

  3. Development of Electrodeposited CIGS Solar Cells: Cooperative Research and Development Final Report, CRADA Number CRD-09-357

    Energy Technology Data Exchange (ETDEWEB)

    Neale, Nathan [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-09-01

    At present, most PV materials are fabricated by vacuum technologies. Some of the many disadvantages of vacuum technology are complicated instrumentation, material waste, high cost of deposition per surface area, and instability of some compounds at the deposition temperature. Solution-based approaches for thin-film deposition on large areas are particularly desirable because of the low capital cost of the deposition equipment, relative simplicity of the processes, ease of doping, uniform deposition on a variety of substrates (including interior and exterior of tubes and various nonplanar devices), and potential compatibility with high-throughput (e.g., roll-to-roll) processing. Of the nonsilicon solar photovoltaic device modules that have been deployed to date, those based on the n-CdS/p-CdTe is a leading candidate. Two features in the optical characteristics of CdTe absorber are particularly attractive for photovoltaic conversion of sunlight; (a) its energy bandgap of 1.5 eV, which provides an optimal match with the solar spectrum and thus facilitates its efficient utilization and (b) the direct mode of the main optical transition which results in a large absorption coefficient and turn permits the use of thin layer (1-2 um) of active material. Thin films of CdTe required for these devices have been fabricated by a variety of methods (e.g., vapor transport deposition, vacuum deposition, screen printing and close-spaced sublimation). Electrodeposition is another candidate deserves more attention. This project will focus on delivering low-cost, high efficiency electrodeposited CdTe-based device.

  4. Electrodeposition of Mg doped ZnO thin film for the window layer of CIGS solar cell

    Science.gov (United States)

    Wang, Mang; Yi, Jie; Yang, Sui; Cao, Zhou; Huang, Xiaopan; Li, Yuanhong; Li, Hongxing; Zhong, Jianxin

    2016-09-01

    Mg doped ZnO (ZMO) film with the tunable bandgap can adjust the conduction band offset of the window/chalcopyrite absorber heterointerface to positive to reduce the interface recombination and resulting in an increasement of chalcopyrite based solar cell efficiency. A systematic study of the effect of the electrodeposition potential on morphology, crystalline structure, crystallographic orientation and optical properties of ZMO films was investigated. It is interestingly found that the prepared doped samples undergo a significant morphological change induced by the deposition potential. With negative shift of deposition potential, an obvious morphology evolution from nanorod structrue to particle covered films was observed. A possible growth mechanism for explaining the morphological change is proposed and briefly discussed. The combined optical techniques including absorption, transmission and photoluminescence were used to study the obtained ZMO films deposited at different potential. The sample deposited at -0.9 V with the hexagonal nanorods morphology shows the highest optical transparency of 92%. The photoluminescence spectra reveal that the crystallization of the hexagonal nanorod ZMO thin film deoposited at -0.9 V is much better than the particles covered ZMO thin film. Combining the structural and optical properties analysis, the obtained normal hexagonal nanorod ZMO thin film could potentially be useful in nanostructured chalcopyrite solar cells to improve the device performance.

  5. Funcionamiento hidrológico de un humedal ribereño, el Masegar, en el conjunto de los humedales de La Mancha Húmeda de la cuenca alta del rió Cigüela

    Directory of Open Access Journals (Sweden)

    Llamas, M. R.

    1995-12-01

    Full Text Available Fifteen years ago «La Mancha Húmeda» was deelared Biosphere Reserve by UNESCO, at the request of the Spanish Government. According to a recent deelaration by UNESCO in 1995, such title could be lost if the degradation processes of the wetlands of «La Mancha Húmeda» continue. «La Mancha Húmeda» was formed by a hundred of small lakes or wetlands that in area totalled about 200-300 km2 and they were distributed over an area of about 25.000 km2. These are different types of wetlands (saltwater and freshwater, permanent and ephimeral, riparian and closed basins, etc.. It is estimated that the actual surface of all the wetlands is about 20-30% of that occupied 20 or 30 years ago. The most famous degradation case is that of the «Tablas de Daimiel National Park» that has shrinked fram an area of about 15-20km2 to less than 1 km2 This article presents the general situation of the riverine wetlands of the Cigüela river and the results of the hydrological functioning of a wetland of modest dimensions, less than 1 km2, El Masegar. It is a riparian wetland located in the Cigüela River basin which has been severely affected by man actions. El Masegar can be considered as an artificial wetland. From an ecological point of view, this wetland seems to have been functioning in a proper way until 1988, when the so called «Plan de Regeneración Hídrica del Parque Nacional de las Tablas de Daimiel» began. This Plan has not regenerated the Natural Park but has degradated or destroyed the riparian wetlands that existed along the Cigüela River valley which is about ISO km long. The surface of these wetlands all together was larger than that of Tablas de Daimiel National Park. The study shows that it could be feasible to restore or maintain most of the riparian wetlands of the «La Mancha Húmeda» without a great economic investment and without social conflicts with the farmers.En 1981, a petición del Gobierno español, la

  6. Investigations into alterntive substrate, absorber, and buffer layer processing for Cu(In,Ga)Se{sub 2}-based solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Tuttle, J.R.; Berens, T.A.; Keane, J. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1996-05-01

    High-performance Cu(In,Ga)Se{sub 2}(CIGS)-based solar cells are presently fabricated within a narrow range of processing options. In this contribution, alternative substrate, absorber, and buffer layer processing is considered. Cell performance varies considerably when alternative substrates are employed. These variations are narrowed with the addition of Na via a Na{sub 2}S compound. Sputtered and electrodeposited CIGS precursors and completed absorbers show promise as alternatives to evaporation. A recrystallization process is required to improve their quality. (In,Ga){sub y}Se buffer layers contribute to cell performance above 10. Further improvements in these alternatives will lead to combined cell performance greater than 10% in the near term.

  7. Fundamental Materials Research and Advanced Process Development for Thin-Film CIS-Based Photovoltaics: Final Technical Report, 2 October 2001 - 30 September 2005

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, T. J.; Li, S. S.; Crisalle, O. D.; Craciun, V.

    2006-09-01

    The objectives for this thin-film copper-indium-diselenide (CIS) solar cell project cover the following areas: Develop and characterize buffer layers for CIS-based solar cell; grow and characterize chemical-bath deposition of Znx Cd1-xS buffer layers grown on CIGS absorbers; study effects of buffer-layer processing on CIGS thin films characterized by the dual-beam optical modulation technique; grow epitaxial CuInSe2 at high temperature; study the defect structure of CGS by photoluminescence spectroscopy; investigate deep-level defects in Cu(In,Ga)Se2 solar cells by deep-level transient spectroscopy; conduct thermodynamic modeling of the isothermal 500 C section of the Cu-In-Se system using a defect model; form alpha-CuInSe2 by rapid thermal processing of a stacked binary compound bilayer; investigate pulsed non-melt laser annealing on the film properties and performance of Cu(In,Ga)Se2 solar cells; and conduct device modeling and simulation of CIGS solar cells.

  8. Progress in Thin Film Solar Cells Based on Cu2ZnSnS4

    OpenAIRE

    Hongxia Wang

    2011-01-01

    The research in thin film solar cells has been dominated by light absorber materials based on CdTe and Cu(In,Ga)Se2 (CIGS) in the last several decades. The concerns of environment impact of cadmium and the limited availability of indium in those materials have driven the research towards developing new substitute light absorbers made from earth abundant, environment benign materials. Cu2ZnSnS4 (CZTS) semiconductor material has emerged as one of the most promising candidates for this aim and h...

  9. Alternative window schemes for CuInSe{sub 2}-based solar cells. Annual report, 1 November 1995--31 October 1996

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, L.C. [Washington State Univ., Richland, WA (United States). Electronic Materials Lab.

    1997-10-01

    The objectives of this program are to develop alternate heterojunction partner layers (buffer layers) for high efficiency CuInSe{sub 2}-based thin-film solar cells, and improve the understanding of how these layers and the details of processing affect cell performance. Investigations have primarily involved three tasks: (1) MOCVD growth of non-cadmium containing buffer layers; (2) optimized processing of buffer layers for high efficiency solar cells; and (3) electrical and physical characterization of layers and devices. Investigations of alternative buffer layers emphasized studies of ZnO grown by MOCVD. Using CIS substrates obtained form Siemens for process development, it was determined that growth procedures that resulted in good results with Siemens CIS (non-sulfur containing material) substrates also worked well with NREL CIGS material. A two step process was developed for growing highly resistive ZnO buffer layers (i-ZnO). In particular, after growing 100 to 150 {angstrom} of ZnO at 250 C, an additional 600 {angstrom} to 800 {angstrom} were grown at 100 C. Collaboration with NREL resulted in a n-ZnO/i-ZnO/CIGS cell which was determined to have a total area efficiency of 12.7%, and an active area efficiency greater than 13%. After growing i-ZnO with the two-step process onto NREL CIGS material, the i-ZnO/CIGS film structure was sent to NREL for deposition of a TCO, namely, conducting ZnO (n-ZnO). Collector grids and a MgF{sub 2} AR coating were also deposited at NREL. Low level efforts were devoted to studies of ZnSe and InSe buffer layers. A total area efficiency of 9.5% was achieved for a completed ZnSe/CIS cell making use of a RF sputtered ZnO for a TCO. Investigations of In{sub x}Se{sub y} (InSe) buffer layers were also initiated this past year.

  10. Cu(In,Ga)Se2 solar cells with controlled conduction band offset of window/Cu(In,Ga)Se2 layers

    International Nuclear Information System (INIS)

    Our group studied the effects of conduction band offset of window/Cu(In,Ga)Se2 (CIGS) layers on CIGS-based solar cell performance. To control the conduction band offset, we considered the use of a window layer of Zn1-xMgxO thin film with a controllable band gap as an alternative to the conventional window layer using CdS film. From the measurement of valence band offset between Zn1-xMgxO/CIGS layers and the band gap of each layer, we confirmed that the conduction band offset of Zn1-xMgxO/CIGS layers could be controlled by changing the Mg content of the Zn1-xMgxO film. The CIGS-based solar cells prepared for this study consisted of an ITO/Zn1-xMgxO/CIGS/Mo/soda-lime glass structure. When the conduction band minimum of Zn1-xMgxO was higher than that of CIGS, the performance of CIGS-based solar cells with a Zn1-xMgxO window layer was equivalent to that of CIGS-based solar cells with CdS window layers. We confirmed that the control of the conduction band offset of the window/CIGS layers decreases the majority carrier recombination via the Zn1-xMgxO/CIGS interface defects. [copyright] 2001 American Institute of Physics

  11. Performance and Loss Analyses of High-Efficiency Chemical Bath Deposition (CBD)-ZnS/Cu(In1-xGax)Se2 Thin-Film Solar Cells

    Science.gov (United States)

    Pudov, Alexei; Sites, James; Nakada, Tokio

    2002-06-01

    Chemically deposited ZnS has been investigated as a buffer layer alternative to cadmium sulfide (CdS) in polycrystalline thin-film Cu(In1-xGax)Se2 (CIGS) solar cells. Cells with efficiency of up to 18.1% based on chemical bath deposition (CBD)-ZnS{\\slash}CIGS heterostructures have been fabricated. This paper presents the performance and loss analyses of these cells based on the current-voltage (J-V) and spectral response curves, as well as comparisons with high efficiency CBD-CdS/CIGS and crystalline silicon counterparts. The CBD-ZnS/CIGS devices have effectively reached the efficiency of the current record CBD-CdS/CIGS cell. The effects of the superior current of the CBD-ZnS/CIGS cell and the superior junction quality of the CBD-CdS/CIGS cell on overall performance nearly cancel each other.

  12. CIG Northern US Rockies and Pacific Northwest Statistical Downscaling

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The goal of this project was to (1) develop consistent historical and future downscaled climate and hydrologic data and projections using the same methodology for...

  13. Spatial atmospheric ALD of functional layers for CIGS Solar Cells

    NARCIS (Netherlands)

    Illiberi, A.; Frijters, C.; Balder, J.E.; Poodt, P.W.G.; Roozeboom, F.

    2015-01-01

    Spatial Atmosperic Atomic Layer Depositon combines the advantages of temporal ALD, i.e. excellent control of film composition and uniformity over large area substrates, with high growth rages (up tot nm/s). In this paper we present a short overview of our research acctivity carried out on S-ALD of f

  14. CIGS nanostructure: preparation and study using liquid phase method

    Science.gov (United States)

    Jakhmola, P.; Jha, P. K.; Bhatnagar, S. P.

    2016-06-01

    Present study is motivated by interesting attainment obtained for copper indium gallium diselenide compound as a light absorbing material for thin-film solar cell. Formation of copper indium gallium diselenide nanostructures via solvothermal method using starting precursors of copper, indium, gallium salts, and selenium powder is represented. Preparation is done by varying x (0.1 and 0.3) in CuIn1- x Ga x Se2 compound at a constant temperature and using ethanolamine as a solvent. Characterization of nanostructures is done using powder X-ray diffraction, scanning electron microscopy, dynamic light scattering, Fourier transform infrared spectroscopy, and UV-Vis spectroscopy. It is found that grown chalcopyrite structure at different x, possess agglomeration in nanostructures. Results indicate that presence of 10 % gallium in copper indium gallium diselenide compound leads to the single-phase growth, prepare at the temperature of 190 °C for 19 h.

  15. Base

    DEFF Research Database (Denmark)

    Hjulmand, Lise-Lotte; Johansson, Christer

    2004-01-01

    BASE - Engelsk basisgrammatik er resultatet af Lise-Lotte Hjulmands grundige bearbejdning og omfattende revidering af Christer Johanssons Engelska basgrammatik. Grammatikken adskiller sig fra det svenske forlæg på en lang række punkter. Den er bl.a. tilpasset til et dansk publikum og det danske...

  16. Factors associated with experimentation of electronic cigarettes among Parisian teenagers in 2013

    OpenAIRE

    Dautzenberg, Bertrand; Berlin, Ivan; Tanguy, Marie-Laure; Rieu, Nicole; Birkui, Pierre

    2015-01-01

    International audience Background: Electronic cigarettes (e-cig.) became widely used among adults. Data are insufficient about e-cig. experimentation among youth. Methods: To assess prevalence of e-cig. experimentation and associated factors among the 12 to 19 years old we analyse a cross sectional school based survey in the city of Paris, France in 2013 on a randomly selected sample of 2 % of schoolchildren (n = 3 279). Self-report questionnaire include demographic, individual and family ...

  17. Copper zinc tin sulfide-based thin film solar cells

    CERN Document Server

    Ito, Kentaro

    2014-01-01

    Beginning with an overview and historical background of Copper Zinc Tin Sulphide (CZTS) technology, subsequent chapters cover properties of CZTS thin films, different preparation methods of CZTS thin films, a comparative study of CZTS and CIGS solar cell, computational approach, and future applications of CZTS thin film solar modules to both ground-mount and rooftop installation. The semiconducting compound (CZTS) is made up earth-abundant, low-cost and non-toxic elements, which make it an ideal candidate to replace Cu(In,Ga)Se2 (CIGS) and CdTe solar cells which face material scarcity and tox

  18. Investigation of Non-Vacuum Deposition Techniques in Fabrication of Chalcogenide-Based Solar Cell Absorbers

    KAUST Repository

    Alsaggaf, Ahmed

    2015-07-01

    The environmental challenges are increasing, and so is the need for renewable energy. For photovoltaic applications, thin film Cu(In,Ga)(S,Se)2 (CIGS) and CuIn(S,Se)2 (CIS) solar cells are attractive with conversion efficiencies of more than 20%. However, the high-efficiency cells are fabricated using vacuum technologies such as sputtering or thermal co-evaporation, which are very costly and unfeasible at industrial level. The fabrication involves the uses of highly toxic gases such as H2Se, adding complexity to the fabrication process. The work described here focused on non-vacuum deposition methods such as printing. Special attention has been given to printing designed in a moving Roll-to-Roll (R2R) fashion. The results show potential of such technology to replace the vacuum processes. Conversion efficiencies for such non-vacuum deposition of Cu(In,Ga)(S,Se)2 solar cells have exceeded 15% using hazardous chemicals such as hydrazine, which is unsuitable for industrial scale up. In an effort to simplify the process, non-toxic suspensions of Cu(In,Ga)S2 molecular-based precursors achieved efficiencies of ~7-15%. Attempts to further simplify the selenization step, deposition of CuIn(S,Se)2 particulate solutions without the Ga doping and non-toxic suspensions of Cu(In,Ga)Se2 quaternary precursors achieved efficiencies (~1-8%). The contribution of this research was to provide a new method to monitor printed structures through spectral-domain optical coherence tomography SD-OCT in a moving fashion simulating R2R process design at speeds up to 1.05 m/min. The research clarified morphological and compositional impacts of Nd:YAG laser heat-treatment on Cu(In,Ga)Se2 absorber layer to simplify the annealing step in non-vacuum environment compatible to R2R. Finally, the research further simplified development methods for CIGS solar cells based on suspensions of quaternary Cu(In,Ga)Se2 precursors and ternary CuInS2 precursors. The methods consisted of post deposition reactive

  19. Electron accelerator-based production of molybdenum-99: Bremsstrahlung and photoneutron generation from molybdenum vs. tungsten

    Science.gov (United States)

    Tsechanski, A.; Bielajew, A. F.; Archambault, J. P.; Mainegra-Hing, E.

    2016-01-01

    A new "one-stage" approach for production of 99Mo and other radioisotopes by means of an electron linear accelerator is described. It is based on using a molybdenum target both as a bremsstrahlung converter and as a radioisotope producing target for the production of 99Mo via the photoneutron reaction 100Mo(γ,n)99Mo. Bremsstrahlung characteristics, such as bremsstrahlung efficiency, angular distribution, and energy deposition for molybdenum targets were obtained by means of the EGSnrc Monte Carlo simulation code system. As a result of our simulations, it is concluded that a 60 MeV electron beam incident on a thick Mo target will have greater bremsstrahlung efficiency than the same thickness (in units of r0) W target, for target thickness z > 1.84r0, where r0 is the electron range. A 50 MeV electron beam incident on a Mo target will result in greater bremsstrahlung efficiency than the same thickness W target (in units of r0) for target thickness case: z ⩾ 2.0r0. It is shown for the one-stage approach with thicknesses of (1.84-2.0)r0, that the 99Mo-production bremsstrahlung efficiency of a molybdenum target is greater by ∼100% at 30 MeV and by ∼70% at 60 MeV compared to the values for tungsten of the same thickness (in units of the appropriate r0) in the traditional two-stage approach (W converter and separate 99Mo producing target). This advantage of the one-stage approach arises from the fact that the bremsstrahlung produced is attenuated only once from attenuation in the molybdenum converter/target. In the traditional, two-stage approach, the bremsstrahlung generated in the W-converter/target is attenuated both in the converter in the 99Mo-producing molybdenum target. The photoneutron production yield of molybdenum and tantalum (as a substitute for tungsten) target was calculated by means of the MCNP5 transport code. On the basis of these data, the specific activity for the one-stage approach of three enriched 100Mo-targets of a 2 cm diameter and

  20. Progress in Thin Film Solar Cells Based on Cu2ZnSnS4

    Directory of Open Access Journals (Sweden)

    Hongxia Wang

    2011-01-01

    Full Text Available The research in thin film solar cells has been dominated by light absorber materials based on CdTe and Cu(In,GaSe2 (CIGS in the last several decades. The concerns of environment impact of cadmium and the limited availability of indium in those materials have driven the research towards developing new substitute light absorbers made from earth abundant, environment benign materials. Cu2ZnSnS4 (CZTS semiconductor material has emerged as one of the most promising candidates for this aim and has attracted considerable interest recently. Significant progress in this relatively new research area has been achieved in the last three years. Over 130 papers on CZTS have been published since 2007, and the majority of them are on the preparation of CZTS thin films by different methods. This paper, will review the wide range of techniques that have been used to deposit CZTS semiconductor thin films. The performance of the thin film solar cells using the CZTS material will also be discussed.

  1. Core/shell-structured upconversion nanophosphor and cadmium-free quantum-dot bilayer-based near-infrared photodetectors.

    Science.gov (United States)

    Hong, A-Ra; Kim, Jungyoon; Kim, Su Yeon; Kim, Seong-Il; Lee, Kwangyeol; Jang, Ho Seong

    2015-11-01

    The core/shell-structured upconversion nanophosphors (UCNPs) and Cd-free CuInS(2)/ZnS quantum dots (QDs) were synthesized via coprecipitation and hot-injection methods, respectively, and they were applied to near infrared (NIR) photodetectors. The β-NaYF(4):Yb,Er/β-NaYF(4) UCNPs emitted intense visible light peaking at 522, 542, and 656 nm via (2)H(11/2), (4)S(3/2), and (4)F(9/2)→(4)I(15/2) transitions under excitation with 980 nm NIR light. The core/shell UCNPs showed 6.4 times higher emission intensity than core UCNPs. Charge carriers can be generated from CuInS(2)/ZnS QDs in the QD-UCNP mixture due to their broad absorption in the visible spectral region shorter than 600 nm. The photodetector devices were fabricated by spin-coating CuInS(2)/ZnS QDs on a SiO(2)/Si substrate with patterned gold electrodes followed by spin-coating UCNPs on the QD layer. The fabricated QD-UCNP-bilayer-based device showed a drastically increased photocurrent (128 μA) compared with the QD-layer-based device under 980 nm NIR light illumination. Additionally, the fabricated device showed stable ON-OFF switching properties against on and off NIR light. PMID:26512493

  2. Knowledge engineering for adverse drug event prevention: on the design and development of a uniform, contextualized and sustainable knowledge-based framework.

    Science.gov (United States)

    Koutkias, Vassilis; Kilintzis, Vassilis; Stalidis, George; Lazou, Katerina; Niès, Julie; Durand-Texte, Ludovic; McNair, Peter; Beuscart, Régis; Maglaveras, Nicos

    2012-06-01

    The primary aim of this work was the development of a uniform, contextualized and sustainable knowledge-based framework to support adverse drug event (ADE) prevention via Clinical Decision Support Systems (CDSSs). In this regard, the employed methodology involved first the systematic analysis and formalization of the knowledge sources elaborated in the scope of this work, through which an application-specific knowledge model has been defined. The entire framework architecture has been then specified and implemented by adopting Computer Interpretable Guidelines (CIGs) as the knowledge engineering formalism for its construction. The framework integrates diverse and dynamic knowledge sources in the form of rule-based ADE signals, all under a uniform Knowledge Base (KB) structure, according to the defined knowledge model. Equally important, it employs the means to contextualize the encapsulated knowledge, in order to provide appropriate support considering the specific local environment (hospital, medical department, language, etc.), as well as the mechanisms for knowledge querying, inference, sharing, and management. In this paper, we present thoroughly the establishment of the proposed knowledge framework by presenting the employed methodology and the results obtained as regards implementation, performance and validation aspects that highlight its applicability and virtue in medication safety.

  3. Buffer layer selection for CuIn1 − xGa xSe2 based thin film solar cells

    International Nuclear Information System (INIS)

    In this work, device modeling and simulation studies have been carried out with a variety of buffer layers over CIGS absorption layer. The band diagram, electric field variation and I/V curves are analyzed and device performance parameters i.e. efficiency, open circuit voltage, short circuit current, quantum efficiency are calculated. The efficiency of CIGS solar cell with ZnSe buffer layer is found comparable with that of CdS layer. The highest short circuit current is found for solar cell with ZnSe buffer layer, whereas the ZnS/CIGS heterojunction provides the highest quantum efficiency in the structures considered. The device physics is discussed and the effect of thickness of buffer layers and absorption layer is studied in order to find a more efficient and stable solar cell. (papers)

  4. Transport, Interfaces, and Modeling in Amorphous Silicon Based Solar Cells: Final Technical Report, 11 February 2002 - 30 September 2006

    Energy Technology Data Exchange (ETDEWEB)

    Schiff, E. A.

    2008-10-01

    Results for a-Si characteristics/modeling; photocarrier drift mobilities in a-Si;H, ..mu..c-Si:H, CIGS; hole-conducting polymers as p-layer for a-Si and c-Si; IR spectra of p/i and n/i interfaces in a-Si.

  5. Fewer Cancer-Causing Chemicals in E-Cigs Than Regular Cigarettes

    Science.gov (United States)

    ... study suggests that smokers who completely switch to e-cigarettes and stop smoking tobacco cigarettes may significantly reduce ... of 12 years. For two weeks, they used e-cigarettes instead of tobacco cigarettes. During that time, their ...

  6. Analysis of performance and device parameters of CIGS PV modules deployed outdoors

    International Nuclear Information System (INIS)

    Two 20 W copper indium gallium diselenide photovoltaic modules were subjected to a thorough indoor assessment procedure, followed by outdoor deployment at the Nelson Mandela Metropolitan University as part of an ongoing study. The initial indoor measurement of maximum power output (PMAX) of one of the modules was considerably higher than the manufacturer's rating (E.E. van Dyk, C. Radue and A.R. Gxasheka, Thin Solid Films 515 (2007) 6196). The modules were deployed on a dual-axis solar tracker and current-voltage characteristics were obtained weekly. In addition to the normal PV parameters of short-circuit current, open-circuit voltage, PMAX, fill factor and efficiency, shunt and series resistances were also monitored. The performances of the two modules are compared and analyzed and the results presented in this paper

  7. Recovery of galium and indium from liquid crystal displays and CIGS photovailtaic modules

    NARCIS (Netherlands)

    Bisselink, R.; Steeghs, W.; Brouwer, J.G.H.

    2014-01-01

    Abstract: The increasing amount of electronics, such as consumer products and green technologies (e.g. solar PV cells) increases the demand of metals such as indium and gallium. This increasing demand together with the dependency on import of these metals drive research on recycling of waste electro

  8. Investigation of sputtered Mo layers on soda-lime glass substrates for CIGS solar cells

    International Nuclear Information System (INIS)

    The influences of deposition parameters on the structural, electrical and mechanical properties of the molybdenum films deposited on the soda-lime glass substrates by dc magnetron sputtering were investigated. The results revealed that there was a significant impact of working pressure on the properties of as-deposited Mo films. The surface morphology of films varied from dense to porous microstructure as working pressure was increased. Under low working pressure, the films possessed low resistivity but poor adhesion. In contrast, the films deposited at high working pressure exhibited good adhesion but high resistivity. Moreover, the high sputtering power and the low sputtering voltage reduced the resistivity and enhanced the adhesion of Mo films, respectively. In order to improve the resistivity and adhesion of Mo films, a bi-layer structure deposited under different conditions was studied. Under the given deposition conditions, both low resistivity of 9.71 µΩ cm and good adhesion have been achieved for the Mo films with a bi-layer structure. (paper)

  9. Thinning of CIGS solar cells: Part I: Chemical processing in acidic bromine solutions

    Energy Technology Data Exchange (ETDEWEB)

    Bouttemy, M.; Tran-Van, P. [Institut Lavoisier de Versailles (ILV-UMR 8180 CNRS/UVSQ), 45 av. des Etats Unis, 78035 Versailles (France); Gerard, I., E-mail: gerard@chimie.uvsq.fr [Institut Lavoisier de Versailles (ILV-UMR 8180 CNRS/UVSQ), 45 av. des Etats Unis, 78035 Versailles (France); Hildebrandt, T.; Causier, A. [Institut Lavoisier de Versailles (ILV-UMR 8180 CNRS/UVSQ), 45 av. des Etats Unis, 78035 Versailles (France); Pelouard, J.L.; Dagher, G. [Laboratoire de Photonique et de Nanostructures (LPN-CNRS), route de Nozay 91460 Marcoussis (France); Jehl, Z.; Naghavi, N. [Institut de Recherche et Developpement sur l' Energie Photovoltaique (IRDEP -UMR 7174 CNRS/EDF/Chimie-ParisTech), 6 quai Watier, 78401 Chatou (France); Voorwinden, G.; Dimmler, B. [Wuerth Elektronik Research GmbH, Industriestr. 4, 70565 Stuttgart (Germany); Powalla, M. [Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung (ZSW), Industriestr. 6, 70565 Stuttgart (Germany); Guillemoles, J.F. [Institut de Recherche et Developpement sur l' Energie Photovoltaique (IRDEP -UMR 7174 CNRS/EDF/Chimie-ParisTech), 6 quai Watier, 78401 Chatou (France); Lincot, D. [Laboratoire de Photonique et de Nanostructures (LPN-CNRS), route de Nozay 91460 Marcoussis (France); Etcheberry, A. [Institut Lavoisier de Versailles (ILV-UMR 8180 CNRS/UVSQ), 45 av. des Etats Unis, 78035 Versailles (France)

    2011-08-31

    CIGSe absorber was etched in HBr/Br{sub 2}/H{sub 2}O to prepare defined thicknesses of CIGSe between 2.7 and 0.5 {mu}m. We established a reproducible method of reducing the absorber thickness via chemical etching. We determine the dissolution kinetics rate of CIGSe using trace analysis by graphite furnace atomic absorption spectrometry of Ga and Cu. The roughness of the etching surface decreases during the first 500 nm of the etching to a steady state value of the root-mean-square roughness near 50 nm. X-ray photoelectron spectroscopy analyses demonstrate an etching process occurring with a constant chemical composition of the treated surface acidic bromine solutions provide a controlled chemical thinning process resulting in an almost flat surface and a very low superficial Se{sup 0} enrichment.

  10. Efficiently-designed hybrid tandem photovoltaic with organic and inorganic single cells

    Science.gov (United States)

    Vincent, Premkumar; Bae, Jin-Hyuk; Kim, Hyeok

    2016-05-01

    Conjugated polymers for solar-cell applications have been extensively studied and have proven highly beneficial in tandem solar-cell structures. This study focuses on achieving power conversion efficiencies of greater than 10% when in tandem with a highly efficient copper indium gallium diselenide (CIGS) solar cell. The optimal design is suggested based on the result of optical simulations on the organic-CIGS tandem structure. This is one of the first reports to show theoretically an organic-CIGS tandem solar cell to obtain an efficiency of greater than 10%. The best PCE was at a thickness of 200 nm for PTB7:PCBM, the active layer of the organic solar cell, and 400 nm for CIGS active layer. Our best datum showed an efficiency of 11.41% with a short-circuit current density of 11.56 mA/cm2 and a good spectral response at our optimized thicknesses.

  11. Barrier effect of AlN film in flexible Cu(In,Ga)Se2 solar cells on stainless steel foil and solar cell

    International Nuclear Information System (INIS)

    Highlights: • The adhension between AlN film and Mo are verygood. • AlN film can be effectively used as the barrier of flexible CIGS solar cell on SS substrate. • AlN film is suitable as the insulation barrier of flexible CIGS solar cell on SS substrate. - Abstract: The AlN film deposited by DC magnetron sputtering on stainless steel (SS) foils was used as the barrier in flexible Cu(In,Ga)Se2 (CIGS) solar cells on stainless steel foil and characterized comprehensively by X-ray diffraction (XRD), scanning electron microscopy (SEM), I–V, and QE measurements study. The study of AlN as insulation barrier in the flexible CIGS solar cell showed that the adhesion strength between the SS foil and the deposited AlN film was very strong even after annealing at high temperature at 530 °C. More importantly, a high resistance of over 10 MΩ was remained with the film with thickness of around 200 nm after annealing. This indicates that the AlN film is suitable as an effective insulation barrier in flexible CIGS solar cells based on SS foil. In addition, the XRD and SEM results showed that the AlN film did not influence the crystal structure of the Mo film which was deposited upon the AlN layer and used as the electrical contact in CIGS solar cells. It was found that the AlN film contributed to an improved crystallinity of the Mo contact layer compared to the bare SS foil. The combined results of secondary ion mass spectrometry, I–V and EQE measurements of the corresponding flexible CIGS solar cells confirmed that 1 μm-thick AlN film could be used as an efficient barrier layer in CIGS solar cells on SS foil

  12. The AMIGA sample of isolated galaxies XII. Revision of the isolation degree for AMIGA galaxies using the SDSS

    CERN Document Server

    Argudo-Fernández, M; Bergond, G; Sulentic, J; Sabater, J; Lorenzo, M Fernández; Leon, S; Espada, D; Verdes-Montenegro, L; Santander-Vela, J D; Ruiz, J E; Sánchez-Expósito, S

    2013-01-01

    In the framework of the AMIGA project we present a revision of the environment for galaxies in the Catalogue of Isolated Galaxies (CIG, Karachentseva 1973) using the ninth data release of the Sloan Digital Sky Survey (SDSS-DR9). The aims of this study are to refine the photometric-based AMIGA sample of isolated galaxies and to provide an improvement of the quantification of the isolation degree with respect to previous works, using both photometry and spectroscopy. We developed an automatic method to search for neighbours within a projected area of 1 Mpc radius centred on each primary galaxy to revise the CIG isolation criteria. Of the 636 CIG galaxies considered in the photometric study, 426 galaxies fulfil the CIG isolation criteria within 1 Mpc, taking into account projected neighbours. Of the 411 CIG galaxies considered in the spectroscopic study, 347 galaxies fulfil the CIG isolation criteria when a criterion about redshift difference is added. The available redshifts allow us to reject background neighb...

  13. ZnS/Zn(O,OH)S-based buffer layer deposition for solar cells

    Science.gov (United States)

    Bhattacharya, Raghu N.

    2009-11-03

    The invention provides CBD ZnS/Zn(O,OH)S and spray deposited ZnS/Zn(O,OH)S buffer layers prepared from a solution of zinc salt, thiourea and ammonium hydroxide dissolved in a non-aqueous/aqueous solvent mixture or in 100% non-aqueous solvent. Non-aqueous solvents useful in the invention include methanol, isopropanol and triethyl-amine. One-step deposition procedures are described for CIS, CIGS and other solar cell devices.

  14. Amorphous Indium Selenide Thin Films Prepared by RF Sputtering: Thickness-Induced Characteristics.

    Science.gov (United States)

    Han, Myoung Yoo; Park, Yong Seob; Kim, Nam-Hoon

    2016-05-01

    The influence of indium composition, controlled by changing the film thickness, on the optical and electrical properties of amorphous indium selenide thin films was studied for the application of these materials as Cd-free buffer layers in CI(G)S solar cells. Indium selenide thin films were prepared using RF magnetron sputtering method. The indium composition of the amorphous indium selenide thin films was varied from 94.56 to 49.72 at% by increasing the film thickness from 30 to 70 nm. With a decrease in film thickness, the optical transmittance increased from 87.63% to 96.03% and Eg decreased from 3.048 to 2.875 eV. Carrier concentration and resistivity showed excellent values of ≥1015 cm(-3) and ≤ 10(4) Ω x cm, respectively. The conductivity type of the amorphous indium selenide thin films could be controlled by changing the film-thickness-induced amount of In. These results indicate the possibility of tuning the properties of amorphous indium selenide thin films by changing their composition for use as an alternate buffer layer material in CI(G)S solar cells.

  15. Antimony assisted low-temperature processing of CuIn1-xGaxSe2-ySy solar cells

    International Nuclear Information System (INIS)

    Application of the Sb-doping method to low-temperature (≤ 400 oC) processing of CuIn1-xGaxSe2-ySy (CIGS) solar cells is explored, using a hydrazine-based approach to deposit the absorber films. Power conversion efficiencies of 10.5% and 8.4% have been achieved for CIGS devices (0.45 cm2 device area) processed at 400 oC and 360 oC, respectively, with an Sb-incorporation level at 1.2 mol % (relative to the moles of CIGS). Significant Sb-induced grain size enhancement was confirmed for these low processing temperatures using cross-sectional scanning electron microscopy, and an average 2-3% absolute efficiency improvement was achieved in Sb-doped samples compared to their Sb-free sister samples. With Sb inclusion, the CIGS film grain growth temperature is lowered to well below 450 oC, a range compatible with flexible polymer substrate materials such as polyimide. This method opens up access to opportunities in low-temperature processing of CIGS solar cells, an area that is being actively pursued using both traditional vacuum-based as well as other solution-based deposition techniques.

  16. Advanced Processing of CdTe- and CuIn{sub x}Ga{sub 1{minus}x}Se{sub 2}-Based Solar Cells; Phase I Report

    Energy Technology Data Exchange (ETDEWEB)

    Morel, D.L.; Ferekides, C.S.

    2000-09-05

    The main tasks of the cadmium telluride portion of this project include the development of simplified processing for fabricating high-efficiency CdTe solar cells, studies on the long-term stability of CdTe devices, and the development of alternative transparent conducting oxides, window layers, and back contacts. The second portion of this project focused on CIGS solar cells. The main tasks include the development of a manufacturable process for CIGS devices and the development of high-band-gap alloys for use in tandem cell structures. Additional objectives include development of improved junction formation processing and contributing to the overall understanding of these materials and devices. Because the processing is manufacturing-driven, the authors use an all solid-state, simplified two-step process that relaxes the level of deposition control required.

  17. Optical methodology for process monitoring of chalcopyrite photovoltaic technologies: Application to low cost Cu(In,Ga)(S,Se)2 electrodeposition based processes

    OpenAIRE

    Oliva, Florian; Kretzschmar, Steffen; Colombara, Diego; Tombolato, Sara; Ruiz, Carmen Maria; Redinger, Alex; Saucedo, Edgardo; Broussillou; Goislard De Monsabert, Thomas; Unold, Thomas; Dale, Phillip; Izquierdo-Roca; Pérez-Rodríguez, Alejandro

    2016-01-01

    Non-destructive characterization of both single layers and completed devices are important issues for the development of efficient and low cost Cu(In,Ga)(S,Se)2 (CIGS) modules at high yields. This implies for the need of methodologies suitable for the assessment of optical, electrical, and physico-chemical parameters that are relevant for the final device efficiency and that can be used for quality control and process monitoring at different process steps. In these applications, detection of ...

  18. Investigation of the diffusion behavior of sodium in Cu(In,Ga)Se{sub 2} layers

    Energy Technology Data Exchange (ETDEWEB)

    Laemmle, Anke, E-mail: anke.laemmle@zsw-bw.de; Wuerz, Roland; Powalla, Michael [Zentrum für Sonnenenergie- und Wasserstoff-Forschung Baden Württemberg, Industriestraße 6, 70565 Stuttgart (Germany); Schwarz, Torsten; Cojocaru-Mirédin, Oana; Choi, Pyuck-Pa [Max-Planck-Institut für Eisenforschung, Max-Planck-Str. 1, 40237 Düsseldorf (Germany)

    2014-04-21

    Sodium diffusion in Cu(In,Ga)Se{sub 2} (CIGS) layers was investigated over a temperature range from 157 °C to 400 °C. The diffusion profiles were measured by secondary ion mass spectrometry. Sodium ions diffused from a sodium fluoride (NaF) layer on the CIGS surface into the CIGS layer. From Na diffusion profiles, the diffusion along grain boundaries could be distinguished from the diffusion into the grain interior. Atom-probe tomography measurements reveal that even at a low temperature of 157 °C bulk diffusion of sodium into CIGS occurs. Based on this data, the slower diffusion coefficient in the volume can be described by the Arrhenius equation D{sub Na}{sup V} = 9.7 × 10{sup −9} exp(−0.36 eV/k{sub B}T) cm{sup 2} s{sup −1} and the fast diffusion along the grain boundaries by D{sub Na}{sup GB} = 6.5 × 10{sup −9} exp(−0.21 eV/k{sub B}T) cm{sup 2} s{sup −1}. Hence, we propose that sodium ions do not only passivate grain boundaries, but also act as dopants in the CIGS bulk.

  19. [Electronic cigarettes: A therapeutic tool, a social phenomenon or a business?].

    Science.gov (United States)

    Berlin, I

    2015-06-01

    Smoking is the first avoidable cause of morbidity and mortality. It is estimated that there were around 14 million smokers in France in 2012 and that smoking results in 70,000 deaths per year. All types of interventions reducing with efficacy the incidence and prevalence of smoking are to consider in prolonging life expectancy. Electronic cigarettes (e.cig.) are a social phenomenon but they also are a system delivering pharmacologically active substances; their use concerns today several millions of individuals in France. By this fact, it became important for clinical practitioners to acquire some knowledge about e. cig. Most of the e.cig. contains nicotine, thus, e.cig. are now called in the medical literature as electronic nicotine delivery system (ENDS). It is highly plausible that ENDS, which are, as of today, consumer products and not health products, deliver nicotine with a good bioavailability and could, if largely used, help to reduce smoking prevalence. However, because of current lack of regulations, as of today, the risk/benefit ratio of ENDS as an aid to help smokers quit and their adverse effect profile cannot be established. It is of public health responsibility to promote evidence based knowledge about e.cig. to know with confidence their risk/benefit ratio. PMID:25534049

  20. Processing and Device Oriented Approach to CIGS Module Reliability; SunShot Initiative, U.S. Department of Energy (DOE)

    Energy Technology Data Exchange (ETDEWEB)

    Ramanathan, K.; Mansfield, L.; Garris, R.; Deline, C.; Silverman, T.

    2015-02-24

    Abstract: A device level understanding of thin film module reliability has been lacking. We propose that device performance and stability issues are strongly coupled and simultaneous attention to both is necessary. Commonly discussed technical issues such as light soaking, metastability, reverse bias breakdown and junction breakdown can be understood by comparing the behaviors of cells made inAbstract: A device level understanding of thin film module reliability has been lacking. We propose that device performance and stability issues are strongly coupled and simultaneous attention to both is necessary. Commonly discussed technical issues such as light soaking, metastability, reverse bias breakdown and junction breakdown can be understood by comparing the behaviors of cells made in the laboratory and industry. It will then be possible to attribute the observed effects in terms of processing and cell design. Process connection to stability studies can help identify root causes and a path for mitigating the degradation.

  1. Recycling of Indium From CIGS Photovoltaic Cells: Potential of Combining Acid-Resistant Nanofiltration with Liquid-Liquid Extraction.

    NARCIS (Netherlands)

    Zimmermann, Y.S.; Niewersch, C.; Lenz, M.; Corvini, P.F.X.; Schäffer, A.; Wintgens, T.

    2014-01-01

    Electronic consumer products such as smartphones, TV, computers, light-emitting diodes, and photovoltaic cells crucially depend on metals and metalloids. So-called “urban mining” considers them as secondary resources since they may contain precious elements at concentrations many times higher than t

  2. Requirement of the SCFPop1/Pop2 Ubiquitin Ligase for Degradation of the Fission Yeast S Phase Cyclin Cig2

    OpenAIRE

    Yamano, H; Kominami, K; Harrison, C; Kitamura, K.; Katayama, S; Dhut, S.; Hunt, T; Toda, T.

    2004-01-01

    Two multiprotein E3 (ubiquitin-protein ligase) ubiquitin ligases, the SCF (Skp1-Cullin-1-F-box) and the APC/C (anaphase promoting complex/cyclosome), are vital in ensuring the temporal order of the cell cycle. Particularly, timely destruction of cyclins via these two E3s is essential for down-regulation of cyclin-dependent kinase. In general, G(1) and S phase cyclins are ubiquitylated by the SCF, whereas ubiquitylation of mitotic cyclins is catalyzed by the APC/C. Here we show that fission ye...

  3. Application of slope-polishing technique for depth profile of selenized CIGS by micro-Raman spectroscopy

    Science.gov (United States)

    Kwon, Min-Su; Kang, Jeong-yoon; Kim, SeongYeon; Kim, JunHo; Jeon, Chan-Wook

    2016-08-01

    Micro-Raman analysis was carried out on two Cu(In,Ga)Se2 films to determine the location of the secondary phases, which were suspected of being formed during the selenization process of Cu-In-Ga metallic precursor films. A slope polishing technique using a dimple grinder was applied to physically expand the film thickness by several hundred fold, which allowed high resolution Raman analysis. Various secondary phases including CuxSe, InSe, Se, and MoySe at different depths were identified without need for time-consuming sputter etching, which may adversely affect the film chemistry. With the help of the new sample preparation method for depth analysis of thin film, a precise decision on the location of those secondary phases along the film thickness and better understanding of the reaction mechanism was enabled.

  4. Motor hidráulico de alto torque de cilindros y cigüeñal

    Directory of Open Access Journals (Sweden)

    Guillermo Arias Polo

    2008-01-01

    Full Text Available El presente trabajo contiene una nueva invención ®, de un tipo de motor hidráulico, para las aplicaciones llamadas de alto torque y baja velocidad de rotación, donde como característica, no es necesario interponer algún escalón de reducción de velocidad entre el motor y el equipo a ser movido. Esta sencilla maquinaria en su construcción tiene el atractivo de utilizar componentes de tecnología muy común en la práctica, de bajo costo, y de poca complejidad. Está compuesto esencialmente por tres cilindros hidráulicos de doble efecto y una válvula distribuidora de flujo rotatoria, montado todo en un bastidor. Tiene la novedad patentada que los tres cilindros hidráulicos mencionados realizan trabajo útil tanto a la ida como al regreso de su carrera, hecho este que le confiere una densidad de torque/masa superior a las soluciones conocidas. Se presenta un prototipo que trabajó en condiciones reales de producción en el ingenio Habana Libre de Cuba, con resultados muy prometedores. Se presenta además, el diseño de un nuevo modelo más robusto, mejorando las prestaciones del prototipo experimental.

  5. CdS and Cd-Free Buffer Layers on Solution Phase Grown Cu2ZnSn(SxSe1- x)4 :Band Alignments and Electronic Structure Determined with Femtosecond Ultraviolet Photoemission Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Haight, Richard; Barkhouse, Aaron; Wang, Wei; Yu, Luo; Shao, Xiaoyan; Mitzi, David; Hiroi, Homare; Sugimoto, Hiroki

    2013-12-02

    The heterojunctions formed between solution phase grown Cu2ZnSn(SxSe1- x)4(CZTS,Se) and a number of important buffer materials including CdS, ZnS, ZnO, and In2S3, were studied using femtosecond ultraviolet photoemission spectroscopy (fs-UPS) and photovoltage spectroscopy. With this approach we extract the magnitude and direction of the CZTS,Se band bending, locate the Fermi level within the band gaps of absorber and buffer and measure the absorber/buffer band offsets under flatband conditions. We will also discuss two-color pump/probe experiments in which the band bending in the buffer layer can be independently determined. Finally, studies of the bare CZTS,Se surface will be discussed including our observation of mid-gap Fermi level pinning and its relation to Voc limitations and bulk defects.

  6. Estimation of defect activation energy around pn interfaces of Cu(In,Ga)Se2 solar cells using impedance spectroscopy

    Science.gov (United States)

    Sakakura, Hidenori; Itagaki, Masayuki; Sugiyama, Mutsumi

    2016-01-01

    We investigate the defect activation energy around the pn interface of Cu(In,Ga)Se2 (CIGS)-based solar cells using a simple electrochemical impedance spectroscopy. By applying AC and DC voltages to the solar cells, we observed an “inductive” element around the pn interface, which is ignored in conventional deep-level transient spectroscopy or admittance spectroscopy. A defect model is evaluated by proposing an equivalent circuit that includes a positive/negative constant phase element (CPE) to represent the area around the CdS/CIGS interface. By fitting the impedance data, the CPE index and CPE constant show a relationship with the defect activation energy or defect concentration. This result is significant because it may help reveal the defect properties of CIGS solar cells or any other semiconductor devices.

  7. Electrodeposition of chalcopyrite films from ionic liquid electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Shivagan, D.D. [Department of Chemistry, University of Bath, BATH BA2 7AY (United Kingdom)]. E-mail: d.shivagan@bath.ac.uk; Dale, P.J. [Department of Chemistry, University of Bath, BATH BA2 7AY (United Kingdom); Samantilleke, A.P. [Department of Chemistry, University of Bath, BATH BA2 7AY (United Kingdom); Peter, L.M. [Department of Chemistry, University of Bath, BATH BA2 7AY (United Kingdom)]. E-mail: l.m.peter@bath.ac.uk

    2007-05-31

    An air and water stable room-temperature ionic liquid based on choline chloride/urea eutectic mixture has been investigated as a system for the electrodeposition of CuInSe{sub 2} (CIS) and Cu(In,Ga)Se{sub 2} (CIGS) films for photovoltaic applications. Deposition potentials and bath compositions were optimized to obtain Cu-In, Cu-In-Se and Cu-In-Ga-Se precursor films, which were selenized in a tube furnace at 500 deg. C for 30 min to form CIS and CI(G)S films. Photo-electrochemical measurements on these selenized films showed p-type photoconductivity with band gaps of 1.0 eV and 1.09 eV, respectively, for CIS and CIGS. The films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), photocurrent spectroscopy and electrolyte electro-reflectance spectroscopy (EER)

  8. Electrodeposition of CuIn1-xGaxSe2 Materials for Solar Cells:

    International Nuclear Information System (INIS)

    This report describes our scientific understanding of the CIGS materials system, solar cells, and processes. Through DOE support, the investigators developed much of the technology and device fabrication infrastructure applied to electrodeposited (ED) materials. The electrodeposition process is simple and fast, and can synthesize multinary precursors for subsequent processing into CuInxGa1-xSe2 (CIGS) thin-film absorbers for solar cells. The device fabricated by using electrodeposited CIGS precursor layers resulted in total-area conversion efficiencies up to 15.4%. As-deposited precursors are Cu-rich CIGS. Additional In, Ga, and Se (up to 50%) are added to the precursor films by physical vapor deposition (PVD) to adjust the final semiconductor film composition to about Cu0.95In0.75Ga0.25Se2. The ED device parameters are compared with those of an 18.8% PVD device. The tools used for comparison are current-voltage, capacitance-voltage, and spectral response characteristics. The individual parameters of the device prepared from ED precursor films showed no significant deterioration from those of the PVD CIGS cells. We also developed a buffer-based electrodeposition bath. Using the buffer solution enhances the stability of the electrodeposition process, and no metal oxides or hydroxides precipitate out of the solution. The buffer-based bath also deposits more gallium in the precursor films. As-deposited precursors are stoichiometric or slightly Cu-rich CIGS. Only a minimal amount (5%-10% of total materials) of indium was added to the ED precursor films by PVD to obtain a 9.4%-efficient device. In general, the films and devices have been characterized by inductively coupled plasma spectrometry, Auger electron spectroscopy, X-ray diffraction, electron-probe microanalysis, current-voltage, capacitance-voltage, and spectral response

  9. A facile chemical-mechanical polishing lift-off transfer process toward large scale Cu(In,Ga)Se2 thin-film solar cells on arbitrary substrates

    Science.gov (United States)

    Tseng, Kuan-Chun; Yen, Yu-Ting; Thomas, Stuart R.; Tsai, Hung-Wei; Hsu, Cheng-Hung; Tsai, Wen-Chi; Shen, Chang-Hong; Shieh, Jia-Min; Wang, Zhiming M.; Chueh, Yu-Lun

    2016-02-01

    The fabrication of Cu(In,Ga)Se2 (CIGS) solar cells on flexible substrates is a non-trivial task due to thermal and ion diffusion related issues. In order to circumvent these issues, we have developed a chemical-mechanical polishing lift-off (CMPL) transfer process, enabling the direct transfer of CIGS solar cells from conventional soda-lime glass (SLG) onto arbitrary flexible substrates up to 4 cm2 in size. The structural and compositional nature of the pre- and post-transferred films is examined using electron microscopy, X-ray diffraction analysis, Raman and photoluminescence spectroscopy. We demonstrate the fabrication of solar cells on a range of flexible substrates while being able to maintain 75% cell efficiency (η) when compared to pre-transferred solar cells. The results obtained in this work suggest that our transfer process offers a highly promising approach toward large scale fabrication of CIGS-based solar cells on a wide variety of flexible substrates, suitable for use in the large scale CIGS photovoltaic industry.The fabrication of Cu(In,Ga)Se2 (CIGS) solar cells on flexible substrates is a non-trivial task due to thermal and ion diffusion related issues. In order to circumvent these issues, we have developed a chemical-mechanical polishing lift-off (CMPL) transfer process, enabling the direct transfer of CIGS solar cells from conventional soda-lime glass (SLG) onto arbitrary flexible substrates up to 4 cm2 in size. The structural and compositional nature of the pre- and post-transferred films is examined using electron microscopy, X-ray diffraction analysis, Raman and photoluminescence spectroscopy. We demonstrate the fabrication of solar cells on a range of flexible substrates while being able to maintain 75% cell efficiency (η) when compared to pre-transferred solar cells. The results obtained in this work suggest that our transfer process offers a highly promising approach toward large scale fabrication of CIGS-based solar cells on a wide

  10. Challenge of replacing CdS in CuInSe{sub 2}-based solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Olsen, L.C.; Addis, F.W.; Lei, W.; Aguilar, H. [Washington State University at Tri-Cities, 100 Sprout Rd., Richland, Washington 99352 (United States)

    1997-02-01

    This paper discusses some key issues concerning the replacement of CdS buffer layers in CIS solar cell structures, and describes investigations of alternative buffer layers deposited by MOCVD. One apparently unique property of CdS buffer layers grown by CBD is that a ZnO TCO can be deposited on top of a CdS/CIS structure without significantly degrading the photovoltaic properties of the CdS-CIS junction. Investigation of alternative buffer materials such as high resistance ZnO (i-ZnO), ZnSe and InSe have first identified MOCVD growth procedures that yield Al/X/CIS test structures (X=i-ZnO, ZnSe and InSe) with good properties, and then addressed the challenge of fabricating efficient, complete cells with conductive ZnO top contact layers. These studies have been conducted with Siemens CIS and CIGSS substrates, and with NREL CIGS substrates. A total area efficiency of 12.7{percent} and estimated active area efficiency of 13.4{percent} is reported for a CIGS cell with an i-ZnO buffer layer grown by MOCVD. {copyright} {ital 1997 American Institute of Physics.}

  11. Challenge of replacing CdS in CuInSe2-based solar cells

    Science.gov (United States)

    Olsen, Larry C.; Addis, F. William; Lei, Wenhua; Aguilar, Heriberto

    1997-02-01

    This paper discusses some key issues concerning the replacement of CdS buffer layers in CIS solar cell structures, and describes investigations of alternative buffer layers deposited by MOCVD. One apparently unique property of CdS buffer layers grown by CBD is that a ZnO TCO can be deposited on top of a CdS/CIS structure without significantly degrading the photovoltaic properties of the CdS-CIS junction. Investigation of alternative buffer materials such as high resistance ZnO (i-ZnO), ZnSe and InSe have first identified MOCVD growth procedures that yield Al/X/CIS test structures (X=i-ZnO, ZnSe and InSe) with good properties, and then addressed the challenge of fabricating efficient, complete cells with conductive ZnO top contact layers. These studies have been conducted with Siemens CIS and CIGSS substrates, and with NREL CIGS substrates. A total area efficiency of 12.7% and estimated active area efficiency of 13.4% is reported for a CIGS cell with an i-ZnO buffer layer grown by MOCVD.

  12. Touch BASE

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    In a recent Nature article (see here), the BASE collaboration reported the most precise comparison of the charge-to-mass ratio of the proton to its antimatter equivalent, the antiproton. This result is just the beginning and many more challenges lie ahead.   CERN's AD Hall, where the BASE experiment is set-up. The Baryon Antibaryon Symmetry Experiment (BASE) was approved in June 2013 and was ready to take data in August 2014. During these 14 months, the BASE collaboration worked hard to set up its four cryogenic Penning traps, which are the heart of the whole experiment. As their name indicates, these magnetic devices are used to trap antiparticles – antiprotons coming from the Antiproton Decelerator – and particles of matter – negative hydrogen ions produced in the system by interaction with a degrader that slows the antiprotons down, allowing scientists to perform their measurements. “We had very little time to set up the wh...

  13. Degradation of Cu(In, Ga)Se2 thin-film solar cells due to the ionization effect of low-energy electrons

    International Nuclear Information System (INIS)

    Cu (In, Ga)Se2 (CIGS) solar cells were irradiated with 100 keV electrons to reveal the characteristics of created radiation defects. 100 keV electrons cannot produce any displacement defects in CIGS. Low-fluence electrons improve the electrical performance of the CIGS solar cells due to the change in the conductive type of donor to acceptor in a metastable defect, which is equivalent to the light-soaking effect. However, high fluence electrons cause the cell performance to decline. From analysis based on changes in carrier density and electroluminescence, defects causing the decline in performance include donor- and non-radiative types. In addition, red-on-bias experiments showed an increase in IIICu defects due to electron irradiation. Based on these results, the degradation in the electrical performance of the CIGS solar cells irradiated with high electron fluence would be attributable to a change in the conductive type of IIICu defects. - Highlights: • Cu(In,Ga)Se2 Solar cells were irradiated with 100 and 250 keV electrons at low temperature. • These electrons degraded the electrical performance of Cu(In,Ga)Se2 sola cells. • The electrons induced ⅢCu defects in Cu(In,Ga)Se2

  14. Web based foundry knowledge base

    Directory of Open Access Journals (Sweden)

    A. Stawowy

    2009-01-01

    Full Text Available The main assumptions and functions of proposed Foundry Knowledge Base (FKB are presented in this paper. FKB is a framework forinformation exchange of casting products and manufacturing methods. We use CMS (Content Management System to develope andmaintain our web-based system. The CastML – XML dialect developed by authors for description of casting products and processes – isused as a tool for information interchange between ours and outside systems, while SQL is used to store and edit knowledge rules and alsoto solve the basic selection problems in the rule-based module. Besides the standard functions (companies data, news, events, forums and media kit, our website contains a number of nonstandard functions; the intelligent search module based on expert system is the main advantage of our solution. FKB is to be a social portal which content will be developed by foundry community.

  15. Beneficial effect of post-deposition treatment in high-efficiency Cu(In,Ga)Se2 solar cells through reduced potential fluctuations

    Science.gov (United States)

    Jensen, S. A.; Glynn, S.; Kanevce, A.; Dippo, P.; Li, J. V.; Levi, D. H.; Kuciauskas, D.

    2016-08-01

    World-record power conversion efficiencies for Cu(In,Ga)Se2 (CIGS) solar cells have been achieved via a post-deposition treatment with alkaline metals, which increases the open-circuit voltage and fill factor. We explore the role of the potassium fluoride (KF) post-deposition treatment in CIGS by employing energy- and time-resolved photoluminescence spectroscopy and electrical characterization combined with numerical modeling. The bulk carrier lifetime is found to increase with post-deposition treatment from 255 ns to 388 ns, which is the longest charge carrier lifetime reported for CIGS, and within ˜40% of the radiative limit. We find evidence that the post-deposition treatment causes a decrease in the electronic potential fluctuations. These potential fluctuations have previously been shown to reduce the open-circuit voltage and the device efficiency in CIGS. Additionally, numerical simulations based on the measured carrier lifetimes and mobilities show a diffusion length of ˜10 μm, which is ˜4 times larger than the film thickness. Thus, carrier collection in the bulk is not a limiting factor for device efficiency. By considering differences in doping, bandgap, and potential fluctuations, we present a possible explanation for the voltage difference between KF-treated and untreated samples.

  16. In-Situ Probing Plasmonic Energy Transfer in Cu(In, Ga)Se2 Solar Cells by Ultrabroadband Femtosecond Pump-Probe Spectroscopy

    Science.gov (United States)

    Chen, Shih-Chen; Wu, Kaung-Hsiung; Li, Jia-Xing; Yabushita, Atsushi; Tang, Shih-Han; Luo, Chih Wei; Juang, Jenh-Yih; Kuo, Hao-Chung; Chueh, Yu-Lun

    2015-12-01

    In this work, we demonstrated a viable experimental scheme for in-situ probing the effects of Au nanoparticles (NPs) incorporation on plasmonic energy transfer in Cu(In, Ga)Se2 (CIGS) solar cells by elaborately analyzing the lifetimes and zero moment for hot carrier relaxation with ultrabroadband femtosecond pump-probe spectroscopy. The signals of enhanced photobleach (PB) and waned photoinduced absorption (PIA) attributable to surface plasmon resonance (SPR) of Au NPs were in-situ probed in transient differential absorption spectra. The results suggested that substantial carriers can be excited from ground state to lower excitation energy levels, which can reach thermalization much faster with the existence of SPR. Thus, direct electron transfer (DET) could be implemented to enhance the photocurrent of CIGS solar cells. Furthermore, based on the extracted hot carrier lifetimes, it was confirmed that the improved electrical transport might have been resulted primarily from the reduction in the surface recombination of photoinduced carriers through enhanced local electromagnetic field (LEMF). Finally, theoretical calculation for resonant energy transfer (RET)-induced enhancement in the probability of exciting electron-hole pairs was conducted and the results agreed well with the enhanced PB peak of transient differential absorption in plasmonic CIGS film. These results indicate that plasmonic energy transfer is a viable approach to boost high-efficiency CIGS solar cells.

  17. Behavior of Photocarriers in the Light-Induced Metastable State in the p-n Heterojunction of a Cu(In,Ga)Se2 Solar Cell with CBD-ZnS Buffer Layer.

    Science.gov (United States)

    Lee, Woo-Jung; Yu, Hye-Jung; Wi, Jae-Hyung; Cho, Dae-Hyung; Han, Won Seok; Yoo, Jisu; Yi, Yeonjin; Song, Jung-Hoon; Chung, Yong-Duck

    2016-08-31

    We fabricated Cu(In,Ga)Se2 (CIGS) solar cells with a chemical bath deposition (CBD)-ZnS buffer layer grown with varying ammonia concentrations in aqueous solution. The solar cell performance was degraded with increasing ammonia concentration, due to actively dissolved Zn atoms during CBD-ZnS precipitation. These formed interfacial defect states, such as hydroxide species in the CBD-ZnS film, and interstitial and antisite Zn defects at the p-n heterojunction. After light/UV soaking, the CIGS solar cell performance drastically improved, with a rise in fill factor. With the Zn-based buffer layer, the light soaking treatment containing blue photons induced a metastable state and enhanced the CIGS solar cell performance. To interpret this effect, we suggest a band structure model of the p-n heterojunction to explain the flow of photocarriers under white light at the initial state, and then after light/UV soaking. The determining factor is a p+ defect layer, containing an amount of deep acceptor traps, located near the CIGS surface. The p+ defect layer easily captures photoexcited electrons, and then when it becomes quasi-neutral, attracts photoexcited holes. This alters the barrier height and controls the photocurrent at the p-n junction, and fill factor values, determining the solar cell performance.

  18. Self-assembled synthesis of 3D Cu(In1 - xGax)Se2 nanoarrays by one-step electroless deposition into ordered AAO template

    Science.gov (United States)

    Zhang, Bin; Zhou, Tao; Zheng, Maojun; Xiong, Zuzhou; Zhu, Changqing; Li, Hong; Wang, Faze; Ma, Li; Shen, Wenzhong

    2014-07-01

    Quaternary nanostructured Cu(In1 - xGax)Se2 (CIGS) arrays were successfully fabricated via a novel and simple solution-based protocol on the electroless deposition method, using a flexible, highly ordered anodic aluminium oxide (AAO) substrate. This method does not require electric power, complicated sensitization processes, or complexing agents, but provides nearly 100% pore fill factor to AAO templates. The field emission scanning electron microscopy (FE-SEM) images show that we obtained uniformly three-dimensional nanostructured CIGS arrays, and we can tailor the diameter and wall thicknesses of the nanostructure by adjusting the pore diameter of the AAO and metal Mo layer. Their chemical composition was determined by energy-dispersive spectroscopy analysis, which is very close to the stoichiometric value. The Raman spectroscopy, x-ray diffraction (XRD) pattern, and transmission electron microscopy (TEM) further confirm the formation of nanostructured CIGS with prominent chalcopyrite structure. The nanostructured CIGS arrays can support the design of low-cost, highlight-trapping, and enhanced carrier collection nanostructured solar cells.

  19. Beneficial Effect of Post-Deposition Treatment in High-Efficiency Cu(In,Ga)Se2 Solar Cells through Reduced Potential Fluctuations

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Soren A.; Glynn, Stephen; Kanevce, Ana; Dippo, Pat; Li, Jian V.; Levi, Dean H.; Kuciauskas, Darius

    2016-08-14

    World-record power conversion efficiencies for Cu(In,Ga)Se2 (CIGS) solar cells have been achieved via a post-deposition treatment with alkaline metals, which increases the open-circuit voltage and fill factor. We explore the role of the potassium fluoride (KF) post-deposition treatment in CIGS by employing energy- and time-resolved photoluminescence spectroscopy and electrical characterization combined with numerical modeling. The bulk carrier lifetime is found to increase with post-deposition treatment from 255 ns to 388 ns, which is the longest charge carrier lifetime reported for CIGS, and within ~40% of the radiative limit. We find evidence that the post-deposition treatment causes a decrease in the electronic potential fluctuations. These potential fluctuations have previously been shown to reduce the open-circuit voltage and the device efficiency in CIGS. Additionally, numerical simulations based on the measured carrier lifetimes and mobilities show a diffusion length of ~10 um, which is ~4 times larger than the film thickness. Thus, carrier collection in the bulk is not a limiting factor for device efficiency. By considering differences in doping, bandgap, and potential fluctuations, we present a possible explanation for the voltage difference between KF-treated and untreated samples.

  20. Synthesis of cadmium-free quantum dots based on CuInS2 nanocrystals

    Science.gov (United States)

    Novikova, Anastasiya S.; Goftman, Valentina V.; Goryacheva, Irina Y.

    2016-04-01

    We report an efficient synthesis Cd-free CuInS2/ZnS (CIS/ZnS) quantum dots (QDs) using low toxic precursors and investigation of their optical properties. The nanocrystals have been obtained via reaction between the acetate salts of the corresponding metals and elemental sulfur in the presence of dodecanethiol in octadecene media at 220°C. Influence of various experimental variables, including temperature, time, ratio of Cu and In precursors were investigated. Thus, it was shown that the photoluminescence (PL) emission wavelength can be tuned by conveniently changing the stoichiometric ratio of the components. The plain CIS nanocrystals did show PL emission but with quite low PL quantum yield (QY). In order to increase the QY of QD luminescence by compensation of the surface defects of QDs cores, the process of covering with ZnS shells was done. During shelling process, increasing of QY and blue shift of emission maximum were detected.

  1. Fabricating Cu(In,Ga)Se2 solar cells on flexible substrates by a new roll-to-roll deposition system suitable for industrial applications

    International Nuclear Information System (INIS)

    In this work, a new hybrid sputtering–evaporation system providing a scalable process for deposition of Cu(In,Ga)Se2 (CIGS) layers is presented. The growth apparatus has been designed and realized to fit a size suitable for direct industrial transfer. In this process the metal precursors are first of all sputtered on rotating transfer devices, then evaporated on the substrate by local heating in a Se atmosphere. The desired thickness and composition of the CIGS film are obtained by repeated sputtering–evaporation cycles. The cylindrical geometry of the deposition chamber has been designed to accommodate different types of flexible substrates with a maximum size of 20 × 120 cm2 in a roll-to-roll configuration. Several techniques, including secondary ion mass spectrometry, Raman and photoluminescence spectroscopies, x-ray diffraction, scanning electron microscopy, external quantum efficiency, and I–V under 1 Sun illumination, have been used to test both the as-grown CIGS layers and the solar cell devices based on them. A significant performance and good control of Ga grading and Na content were obtained for solar cells grown at 450 °C on polyimide substrates with high deposition rates. In spite of the fact that the present efficiency record for CIGS solar cells on polyimide substrates is 20.4%, the 10.1% obtained using the hybrid method presented in this work is significant because the growth apparatus meets the requirements for direct industrial transfer. In fact, this process is being transferred in a 1 MW production line, where standard CIGS layers are deposited at low temperature on flexible substrates in a single-step process with a 1 mm sec−1 substrate velocity. (paper)

  2. Insight into the mechanism of Sb promoted Cu(In,Ga)Se2 formation

    International Nuclear Information System (INIS)

    Sb-doping has been demonstrated to be a new approach to promote Cu(In,Ga)Se2 (CIGS) thin film formation. To study the mechanism of Sb-promoted CIGS formation, we investigated the influence of Sb on the evolution of the critical intermediate Cu–Se phases, and found that Cu3SbSe3 species was formed. Phase change of the as-prepared Cu–Se compounds at elevated temperature was determined using the differential scanning calorimetry analysis. For samples containing Sb, the melting decomposition occurred at 507.1 °C, along with aggregation of nanocrystals into a bulk, while the morphology of the sample without Sb barely changed after heating. This result suggests that the mobile Cu3SbSe3 is likely the key intermediate responsible for Sb-promoted CIGS formation. Furthermore, we extended the scope of Sb-doping approach to solvothermal synthesis and CIGS nanocrystals were synthesized with significantly promoted kinetics in the presence of Sb. Based on these results, we propose the mechanism of Sb promoted CIGS formation. - Graphical abstract: Cu3SbSe3 mobile phase is likely the key species to promote the formation of Cu(In,Ga)Se2, and significantly promoting effect by Sb is also found in the synthesis of Cu(In,Ga)Se2 nanocrystals. Highlights: • In the presence of Sb, Cu3SbSe3 is formed while synthesizing the essential intermediate Cu–Se compounds for Cu(In,Ga)Se2 materials. • Cu3SbSe3 shows high mobility at elevated temperature. • Cu3SbSe3 mobile phase is likely the key species to improve Cu(In,Ga)Se2 thin film formation. • A synthesis methodology is developed to produce Cu(In,Ga)Se2 nanocrystals with significantly promoted reaction kinetics

  3. Analysis of the process of representing clinical statements for decision-support applications: a comparison of openEHR archetypes and HL7 virtual medical record.

    Science.gov (United States)

    González-Ferrer, A; Peleg, M; Marcos, M; Maldonado, J A

    2016-07-01

    Delivering patient-specific decision-support based on computer-interpretable guidelines (CIGs) requires mapping CIG clinical statements (data items, clinical recommendations) into patients' data. This is most effectively done via intermediate data schemas, which enable querying the data according to the semantics of a shared standard intermediate schema. This study aims to evaluate the use of HL7 virtual medical record (vMR) and openEHR archetypes as intermediate schemas for capturing clinical statements from CIGs that are mappable to electronic health records (EHRs) containing patient data and patient-specific recommendations. Using qualitative research methods, we analyzed the encoding of ten representative clinical statements taken from two CIGs used in real decision-support systems into two health information models (openEHR archetypes and HL7 vMR instances) by four experienced informaticians. Discussion among the modelers about each case study example greatly increased our understanding of the capabilities of these standards, which we share in this educational paper. Differing in content and structure, the openEHR archetypes were found to contain a greater level of representational detail and structure while the vMR representations took fewer steps to complete. The use of openEHR in the encoding of CIG clinical statements could potentially facilitate applications other than decision-support, including intelligent data analysis and integration of additional properties of data items from existing EHRs. On the other hand, due to their smaller size and fewer details, the use of vMR potentially supports quicker mapping of EHR data into clinical statements. PMID:27209183

  4. Intermixing at the absorber-buffer layer interface in thin-film solar cells: The electronic effects of point defects in Cu(In,Ga)(Se,S){sub 2} and Cu{sub 2}ZnSn(Se,S){sub 4} devices

    Energy Technology Data Exchange (ETDEWEB)

    Varley, J. B.; Lordi, V. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2014-08-14

    We investigate point defects in the buffer layers CdS and ZnS that may arise from intermixing with Cu(In,Ga)(S,Se){sub 2} (CIGS) or Cu{sub 2}ZnSn(S,Se){sub 4} (CZTS) absorber layers in thin-film photovoltaics. Using hybrid functional calculations, we characterize the electrical and optical behavior of Cu, In, Ga, Se, Sn, Zn, Na, and K impurities in the buffer. We find that In and Ga substituted on the cation site act as shallow donors in CdS and tend to enhance the prevailing n-type conductivity at the interface facilitated by Cd incorporation in CIGS, whereas they are deep donors in ZnS and will be less effective dopants. Substitutional In and Ga can favorably form complexes with cation vacancies (A-centers) which may contribute to the “red kink” effect observed in some CIGS-based devices. For CZTS absorbers, we find that Zn and Sn defects substituting on the buffer cation site are electrically inactive in n-type buffers and will not supplement the donor doping at the interface as in CIGS/CdS or ZnS devices. Sn may also preferentially incorporate on the S site as a deep acceptor in n-type ZnS, which suggests possible concerns with absorber-related interfacial compensation in CZTS devices with ZnS-derived buffers. Cu, Na, and K impurities are found to all have the same qualitative behavior, most favorably acting as compensating acceptors when substituting on the cation site. Our results suggest one beneficial role of K and Na incorporation in CIGS or CZTS devices is the partial passivation of vacancy-related centers in CdS and ZnS buffers, rendering them less effective interfacial hole traps and recombination centers.

  5. Composition and emissions of VOCs in main- and side-stream smoke of research cigarettes

    Science.gov (United States)

    Charles, Simone M.; Batterman, S. A.; Jia, Chunrong

    It is well known that mainstream (MS) and sidestream (SS) cigarette smoke contains a vast number of chemical substances. Previous studies have emphasized SS smoke rather than MS smoke to which smokers are exposed, and most have used chamber tests that have several disadvantages such as wall losses. Emissions from standard research cigarettes have been measured, but relatively few constituents have been reported, and only the 1R4F (low nicotine) cigarette type has been tested. This study provides a comprehensive characterization of total, MS and SS smoke emissions for the 1R5F (ultra low nicotine), 2R4F (low nicotine), and 1R3F (standard nicotine) research cigarettes research cigarettes, including emission factors for a number of toxic compounds (e.g., benzene) and tobacco smoke tracers (e.g., 2,5-dimethyl furan). Emissions of volatile organic compounds (VOCs) and particulate matter (PM) are quantified using a dynamic dilution emission measurement system that is shown to produce accurate, rapid and reproducible results for over 30 VOCs and PM. SS and MS emissions were accurately apportioned based on a mass balance of total emissions. As expected, SS emissions greatly exceeded MS emissions. The ultra low nicotine cigarette had lower emissions of most VOCs compared to low and standard nicotine cigarettes, which had similar emissions. Across the three types of cigarettes, emissions of benzene (296-535 μg cig -1), toluene (541-1003 μg cig -1), styrene (90-162 μg cig -1), 2-dimethyl furan (71-244 μg cig -1), naphthalene (15-18 μg cig -1) and other VOCs were generally comparable to or somewhat higher than literature estimates using chamber tests.

  6. Junction formation in CuInSe{sub 2}-based thin-film devices

    Energy Technology Data Exchange (ETDEWEB)

    Ramanathan, K.; Wiesner, H.; Asher, S.; Bhattacharya, R.N.; Keane, J.; Contreras, M.A.; Noufi, R. [National Center for Photovoltaics, National Renewable Energy Laboratory, 1617 Cole Boulevard, Golden, Colorado 80401 (United States)

    1999-03-01

    The nature of the interface between CuInSe{sub 2} (CIS) and the chemical bath deposited CdS layer has been investigated. We show that heat-treating the absorbers in Cd- or Zn-containing solutions in the presence of ammonium hydroxide sets up a chemical reaction which facilitates an extraction of Cu from the lattice and an in-diffusion of Cd. The characteristics of devices made in this manner suggest that the reaction generates a thin, n-doped region in the absorber. It is quite possible that the CdS/CuInSe{sub 2} device is a buried, shallow junction with a CdS window layer, rather than a heterojunction. We have used these ideas to develop methods for fabricating devices without CdS or Cd. A 14.2{percent} efficiency ZnO/CIGS device was obtained through aqueous treatment in Zn solutions. {copyright} {ital 1999 American Institute of Physics.}

  7. Junction Formation in CuInSe{sub 2} Based Thin Film Devices

    Energy Technology Data Exchange (ETDEWEB)

    Ramanathan, K.; Wiesner, H.; Asher, S.; Bhattacharya, R. N.; Keane, J.; Contreras, M.; Noufi, R.

    1998-11-18

    The nature of the interface between CuInSe{sub 2} (CIS) and the chemical bath deposited CdS layer has been investigated. We show that heat-treating the absorbers in Cd- or Zn-containing solutions in the presence of ammonium hydroxide sets up a chemical reaction which facilitates an extraction of Cu from the lattice and an in-diffusion of Cd. The characteristics of devices made in this manner suggest that the reaction generates a thin, n-doped region in the absorber. It is quite possible that the CdS/CuInSe{sub 2} device is a buried, shallow junction with a CdS window layer, rather than a heterojunction. We have used these ideas to develop methods for fabricating devices without CdS or Cd. A 14.2% efficiency ZnO/CIGS device was obtained through aqueous treatment in Zn solutions.

  8. Room-Temperature Chemical Solution Treatment for Flexible ZnS(O,OH)/Cu(In,Ga)Se2 Solar Cell: Improvements in Interface Properties and Metastability.

    Science.gov (United States)

    Ho, Wei-Hao; Hsu, Chia-Hao; Yeh, Tzu-Hsuan; Chang, Yu-Han; Wei, Shih-Yuan; Lin, Tzu-Ying; Lai, Chih-Huang

    2016-03-01

    We demonstrate an effective room-temperature chemical solution treatment, by using thioacetamide (S treatment) or thioacetamide-InCl3 (In-S treatment) solution, on Cu(In,Ga)Se2 (CIGSe) surface to engineer the ZnS(O,OH)/CIGSe interface and junction quality, leading to enhanced efficiency and minimized metastability of flexible solar cells. The control device without treatment reveals a relatively low efficiency of 8.15%, which is significantly improved to 9.74% by In-S treatment, and 10.39% by S treatment. Results of X-ray photoelectron spectroscopy suggest that S is incorporated into CIGSe surface forming CIGSSe by S treatment, whereas a thin In-S layer is formed on CIGSe surface by In-S treatment with reduced amount of S diffusing into CIGSe. PL spectra and TRPL lifetime further reveal that S incorporation into CIGS surface may substitute the OSe and/or directly occupy the vacant anion site (VSe), resulting in the effective passivation of the recombination centers at CIGSe surface. Moreover, reducing the concentrations of VSe may thereby decrease the density of (VCu-VSe) acceptors, which can minimize the metastability of ZnS(O,OH)/CIGSe solar cells. With S treatment, the light soaking (LS) time of ZnS(O,OH)/CIGSe device is reduced approximately to one-half of control one. Our approach can be potentially applied for alternative Cd-free buffer layers to achieve high efficiency and low metastability. PMID:26905219

  9. Foundation: Transforming data bases into knowledge bases

    Science.gov (United States)

    Purves, R. B.; Carnes, James R.; Cutts, Dannie E.

    1987-01-01

    One approach to transforming information stored in relational data bases into knowledge based representations and back again is described. This system, called Foundation, allows knowledge bases to take advantage of vast amounts of pre-existing data. A benefit of this approach is inspection, and even population, of data bases through an intelligent knowledge-based front-end.

  10. Modelado de un motor en Simpack como sistema multicuerpo y análisis modal de su cigüeñal

    OpenAIRE

    Sánchez Fernández, Jorge

    2015-01-01

    En el siguiente Trabajo Fin de Grado se analiza el modelado de un sistema multicuerpo. El modelo consiste en un motor de combustión interna alternativo de cuatro cilindros en línea. Para llevar el proceso a cabo se hace uso de un software de simulación con sistemas multicuerpos llamado Simpack. Se detalla el proceso de modelado de cada cuerpo realizando posteriormente el ensamblaje de los mismos. El módulo Flexmodal que implementa Simpack permite hacer análisis modales de un cuerpo flexibl...

  11. Research Advances of CIGS Cells, Target and Single Target Sputtering Progress%CIGS电池、靶材及单靶溅射工艺研究进展

    Institute of Scientific and Technical Information of China (English)

    王丹; 余洲; 冀亚欣; 闫勇; 欧玉峰; 晏传鹏; 刘连; 张勇; 赵勇

    2016-01-01

    综述了蒸发法、溅射后硒化法、单靶直接溅射法制备CIGS光吸收层的工艺和电池性能,比较了它们的优缺点;详细介绍了粉末冶金参数(如烧结温度、压力、时间)对制备CIGS靶材致密度、成分均匀性的影响;着重阐述了单靶溅射工艺参数(如衬底温度、溅射功率、工作气压)对沉积的CIGS薄膜的相结构、形貌、光学及电学性能的影响.

  12. Dialektika cigánské férovky. Příspěvek ke kritické antropologii bezpečnosti

    Directory of Open Access Journals (Sweden)

    Václav Walach

    2013-12-01

    Full Text Available Within a Czech socially excluded locality,street violence is recognized as a serious securitythreat. This paper deals with several interpretationsof this phenomenon which is oftentimessymbolized as the ‘Gypsy fair fight’. It is analyzedvia the dialectical method structured around thethesis–antithesis–synthesis conceptual triad.While a prevailing explication in the discourseof respective locale comprehends street violencein terms of ethnic conflict, a less frequent one opposesthis interpretation on the basis of culturalconflict between the so-called decent and inadaptablepeople. The last stage of analysis consists ofre-reading these accounts from the perspectiveemphasizing structural factors in a ‘Gypsy fairfight’ explanation. The aim of the paper is to localizethe social experience of (insecurity in relationto the political order and social structure. Takingthem into account, we can aspire to sociologicallyrelevant knowledge of how security discoursesand practices shape our everyday ways of being.

  13. Numerical Analysis of In2S3 Layer Thickness, Band Gap and Doping Density for Effective Performance of a CIGS Solar Cell Using SCAPS

    Science.gov (United States)

    Khoshsirat, Nima; Md Yunus, Nurul Amziah

    2016-11-01

    The effect of indium sulfide buffer layer's geometrical and electro-optical properties on the Copper-Indium-Gallium-diSelenide solar cell performance using numerical simulation is investigated. The numerical simulation software used is a solar cell capacitance simulator in (SCAPS). The innermost impacts of buffer layer thickness, band gap, and doping density on the cells output parameters such as open circuit voltage, short circuit current density, fill factor, and the efficiency were extensively simulated. The results show that the cell efficiency, which was innovatively illustrated as a two-dimensional contour plot function, depends on the buffer layer electron affinity and doping density by keeping all the other parameters at a steady state. The analysis, which was made from this numerical simulation, has revealed that the optimum electron affinity is to be 4.25 ± 0.2 eV and donor density of the buffer layer is over 1× 10 ^{17} cm^{-3}. It is also shown that the cell with an optimum thin buffer layer has higher performance and efficiency due to the lower optical absorption of the buffer layer.

  14. First principles based multiparadigm modeling of electronic structures and dynamics

    Science.gov (United States)

    Xiao, Hai

    Electronic structures and dynamics are the key to linking the material composition and structure to functionality and performance. An essential issue in developing semiconductor devices for photovoltaics is to design materials with optimal band gaps and relative positioning of band levels. Approximate DFT methods have been justified to predict band gaps from KS/GKS eigenvalues, but the accuracy is decisively dependent on the choice of XC functionals. We show here for CuInSe2 and CuGaSe2, the parent compounds of the promising CIGS solar cells, conventional LDA and GGA obtain gaps of 0.0-0.01 and 0.02-0.24 eV (versus experimental values of 1.04 and 1.67 eV), while the historically first global hybrid functional, B3PW91, is surprisingly the best, with band gaps of 1.07 and 1.58 eV. Furthermore, we show that for 27 related binary and ternary semiconductors, B3PW91 predicts gaps with a MAD of only 0.09 eV, which is substantially better than all modern hybrid functionals, including B3LYP (MAD of 0.19 eV) and screened hybrid functional HSE06 (MAD of 0.18 eV). The laboratory performance of CIGS solar cells (> 20% efficiency) makes them promising candidate photovoltaic devices. However, there remains little understanding of how defects at the CIGS/CdS interface affect the band offsets and interfacial energies, and hence the performance of manufactured devices. To determine these relationships, we use the B3PW91 hybrid functional of DFT with the AEP method that we validate to provide very accurate descriptions of both band gaps and band offsets. This confirms the weak dependence of band offsets on surface orientation observed experimentally. We predict that the CBO of perfect CuInSe2/CdS interface is large, 0.79 eV, which would dramatically degrade performance. Moreover we show that band gap widening induced by Ga adjusts only the VBO, and we find that Cd impurities do not significantly affect the CBO. Thus we show that Cu vacancies at the interface play the key role in

  15. INVOLUTIVE BASES UNDER COMPOSITION

    Institute of Scientific and Technical Information of China (English)

    Zailiang TANG

    2007-01-01

    In this paper, the behaviors of involutive bases under composition operation are studied.For two kinds of involutive bases, i.e., Pommaret bases, Janet bases, we study their behavior problems under composition. Some further problems are also proposed.

  16. A dynamic knowledge base based search engine

    Institute of Scientific and Technical Information of China (English)

    WANG Hui-jin; HU Hua; LI Qing

    2005-01-01

    Search engines have greatly helped us to find thedesired information from the Intemet. Most search engines use keywords matching technique. This paper discusses a Dynamic Knowledge Base based Search Engine (DKBSE), which can expand the user's query using the keywords' concept or meaning. To do this, the DKBSE needs to construct and maintain the knowledge base dynamically via the system's searching results and the user's feedback information. The DKBSE expands the user's initial query using the knowledge base, and returns the searched information after the expanded query.

  17. Manufacturing technology development for CuInGaSe2 solar cell modules

    Science.gov (United States)

    Stanbery, B. J.

    1991-11-01

    The report describes research performed by Boeing Aerospace and Electronics under the Photovoltaic Manufacturing Technology project. We anticipate that implementing advanced semiconductor device fabrication techniques to the production of large area CuIn(1-x)Ga(x)Se2 (CIGS)/Cd(1-y)Zn(y)S/ZnO monolithically integrated thin film solar cell modules will enable 15 pct. median efficiencies to be achieved in high volume manufacturing. We do not believe that CuInSe2 (CIS) can achieve this efficiency in production without sufficient gallium to significantly increase the band gap, thereby matching it better to the solar spectrum (i.e., x greater than or = 0.2). Competing techniques for CIS film formation have not been successfully extended to CIGS devices with such high band gaps. The SERI-confirmed intrinsic stability of CIS-based photovoltaics renders them far superior to a-Si:H-based devices, making a 30 year module lifetime feasible. The minimal amounts of cadmium used in the structure we propose, compared to CdTe-based devices, makes them environmentally safer and more acceptable to both consumers and relevant regulatory agencies. Large area integrated thin film CIGS modules are the product most likely to supplant silicon modules by the end of this decade and enable the cost improvements which will lead to rapid market expansion.

  18. Manufacturing technology development for CuInGaSe{sub 2} solar cell modules. Final subcontract report, 9 January 1991--14 April 1991

    Energy Technology Data Exchange (ETDEWEB)

    Stanbery, B.J. [Boeing Aerospace and Electronics Co., Seattle, WA (US)

    1991-11-01

    The report describes research performed by Boeing Aerospace and Electronics under the Photovoltaic Manufacturing Technology project. We anticipate that implementing advanced semiconductor device fabrication techniques to the production of large-area CuIn{sub 1-x}Ga{sub x}Se{sub 2} (CIGS)/Cd{sub 1-y}Zn{sub y}S/ZnO monolithically integrated thin-film solar cell modules will enable 15% median efficiencies to be achieved in high-volume manufacturing. We do not believe that CuInSe{sub 2} (CIS) can achieve this efficiency in production without sufficient gallium to significantly increase the band gap, thereby matching it better to the solar spectrum (i.e., x{>=}0.2). Competing techniques for CIS film formation have not been successfully extended to CIGS devices with such high band gaps. The SERI-confirmed intrinsic stability of CIS-based photovoltaics renders them far superior to a-Si:H-based devices, making a 30-year module lifetime feasible. The minimal amounts of cadmium used in the structure we propose, compared to CdTe-based devices, makes them environmentally safer and more acceptable to both consumers and relevant regulatory agencies. Large-area integrated thin-film CIGS modules are the product most likely to supplant silicon modules by the end of this decade and enable the cost improvements which will lead to rapid market expansion.

  19. Manufacturing technology development for CuInGaSe sub 2 solar cell modules

    Energy Technology Data Exchange (ETDEWEB)

    Stanbery, B.J. (Boeing Aerospace and Electronics Co., Seattle, WA (United States))

    1991-11-01

    The report describes research performed by Boeing Aerospace and Electronics under the Photovoltaic Manufacturing Technology project. We anticipate that implementing advanced semiconductor device fabrication techniques to the production of large-area CuIn{sub 1-x}Ga{sub x}Se{sub 2} (CIGS)/Cd{sub 1-y}Zn{sub y}S/ZnO monolithically integrated thin-film solar cell modules will enable 15% median efficiencies to be achieved in high-volume manufacturing. We do not believe that CuInSe{sub 2} (CIS) can achieve this efficiency in production without sufficient gallium to significantly increase the band gap, thereby matching it better to the solar spectrum (i.e., x{ge}0.2). Competing techniques for CIS film formation have not been successfully extended to CIGS devices with such high band gaps. The SERI-confirmed intrinsic stability of CIS-based photovoltaics renders them far superior to a-Si:H-based devices, making a 30-year module lifetime feasible. The minimal amounts of cadmium used in the structure we propose, compared to CdTe-based devices, makes them environmentally safer and more acceptable to both consumers and relevant regulatory agencies. Large-area integrated thin-film CIGS modules are the product most likely to supplant silicon modules by the end of this decade and enable the cost improvements which will lead to rapid market expansion.

  20. Impact of Cu-rich growth on the Cu2ZnSnSe4 surface morphology and related solar cells behavior

    Science.gov (United States)

    Ding, Sun; Yang, Ge; Li, Zhang; Shengzhi, Xu; Ze, Chen; Ning, Wang; Xuejiao, Liang; Changchun, Wei; Ying, Zhao; Xiaodan, Zhang

    2016-01-01

    In order to study the influence of Cu-rich growth on the performance of the Cu2ZnSnSe4 (CZTSe) thin film solar cells, a multi-stage co-evaporation process is applied. The CZTSe films are grown at a lower substrate temperature to reduce the existence time of Cux Sey at the first period caused by the volatility of SnSex. This study examines the surface morphology and device performance in Cu-rich growth and close-to-stoichiometric growth. Although the grain size of Cu-rich growth film increases a little, the difference was not dramatic as the results of CIGS reported previously. A model based on the grain boundary migration theory is proposed to explain the experimental results. The mechanisms of Cu-rich growth between CZTSe and CIGS might be different. Project supported by the Specialized Research Fund for the PhD Program of Higher Education (No. 20120031110039).

  1. Knowledge Based Strategies for Knowledge Based Organizations

    Directory of Open Access Journals (Sweden)

    Madalina Cristina Tocan

    2012-12-01

    Full Text Available In the present, we can observe that a new economy is arising. It is an economy based on knowledge and ideas, in which the key factor for prosperity and for creation of the new jobs is the knowledge capitalization. Knowledge capitalization, intellectual capital, obtaining prosperity in the market economy imposes a new terminology, new managerial methods and techniques, new technologies and also new strategies. In other words, knowledge based economy, as a new type of economy; impose a new type of management- knowledge based management and a new type of enterprise-knowledge based enterprise.Taking in consideration these predictable evolutions, this paper will try to present: • The main ideas of the researches the field of the knowledge based economy • The characteristics and principles of the knowledge based organizations and knowledge based management • The challenges and opportunities for knowledge based organizations.The first part of the paper will present the principles of the new economy- knowledge base economy, the essential and interrelated elements necessary to build and to implement a strategy in a knowledge economy and the opportunities and challenges to the countries as they seek to build regionally and globally competitive knowledge-based economies.The second part of the paper will present the characteristics of the knowledge based organizations, the principles and characteristics of their management. For many organizations, knowledge management is a relatively new concept, because they are discovering the knowledge value in their operations. Many firms have undertaken formal and informal knowledge management initiatives designed to improve process performance, increase customer responsiveness and spur innovation. But while some organizations have reaped significant benefits from their investment in knowledge efforts, others have run into noteworthy challenges.

  2. Solid Base Catalysis

    CERN Document Server

    Ono, Yoshio

    2011-01-01

    The importance of solid base catalysts has come to be recognized for their environmentally benign qualities, and much significant progress has been made over the past two decades in catalytic materials and solid base-catalyzed reactions. The book is focused on the solid base. Because of the advantages over liquid bases, the use of solid base catalysts in organic synthesis is expanding. Solid bases are easier to dispose than liquid bases, separation and recovery of products, catalysts and solvents are less difficult, and they are non-corrosive. Furthermore, base-catalyzed reactions can be performed without using solvents and even in the gas phase, opening up more possibilities for discovering novel reaction systems. Using numerous examples, the present volume describes the remarkable role solid base catalysis can play, given the ever increasing worldwide importance of "green" chemistry. The reader will obtain an overall view of solid base catalysis and gain insight into the versatility of the reactions to whic...

  3. Fiscal 1994 New Sunshine Program achievement report. Development of photovoltaic power generation system practicalization technology - Research on practicalization of thin-film solar cell manufacturing technology (Technology for higher quality - Development of CuInSe{sub 2} solar cell manufacturing technology); 1994 nendo taiyoko hatsuden system jitsuyoka gijutsu kaihatsu seika hokokusho. Usumaku taiyo denchi seizo gijutsu no jitsuyoka kenkyu (kohinshitsuka gijutsu (CuInSe{sub 2} taiyo denchi seizo no gijutsu kaihatsu))

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    The aim is to develop solar cells that exhibit conversion efficiency of 12% in a 10cm times 10cm-large minimodule. When a substrate made of soda lime glass with an SiO{sub 2} coating thereon is used, high reproducibility is achieved in the manufacture of CuInSe{sub 2} (CIS) thin-film solar cells. For the manufacture of a high-quality Cu(InGa)Se{sub 2}(CIGS) light absorbing thin-film layer, it is necessary to develop high-quality precursor film manufacturing and gas phase selenization technologies. A laminated precursor film formed by sputtering is selenized in a H{sub 2}Se gas atmosphere for the formation of CuInSe{sub 2} and CIGS light absorbing thin-film layers, and 16 ZnO/CdS/CIS-structured thin film solar cells built into a 10cm times 10cm-large substrate exhibit conversion efficiency of 11.6%. A CIGS cell using a sulfur-containing Zn compound buffer layer exhibits conversion efficiency of 12.1%. Conditions for the manufacture of a ZnO:Al transparent conductive film are studied. Dependence of CIS-based solar cell output characteristics on temperature and irradiation may be compensated for under the JIS (Japanese Industrial Standard) compensatory formula. The CIS-based thin-film solar cell suffers but a little reduction in output due to temperature rise, and may be therefore said to be excellent. (NEDO)

  4. Cu(In,Ga)Se{sub 2} solar cells with double layered buffers grown by chemical bath deposition

    Energy Technology Data Exchange (ETDEWEB)

    Li, Z.Q.; Shi, J.H.; Zhang, D.W.; Liu, Q.Q.; Sun, Z.; Chen, Y.W. [Engineering Research Center for Nanophotonics and Advanced Instrument, Ministry of Education, Department of Physics, East China Normal University, North Zhongshan Rd. 3663, Shanghai 200062 (China); Yang, Z. [Key Laboratory for Thin Film and Microfabrication of the Ministry of Education, Research Institute of Micro/Nano Science and Technology, Shanghai Jiao Tong University, Shanghai 200240 (China); Huang, S.M., E-mail: engp5591@yahoo.com [Engineering Research Center for Nanophotonics and Advanced Instrument, Ministry of Education, Department of Physics, East China Normal University, North Zhongshan Rd. 3663, Shanghai 200062 (China)

    2011-10-31

    In based mixture In{sub x}(OH,S){sub y} buffer layers deposited by chemical bath deposition technique are a viable alternative to the traditional cadmium sulfide buffer layer in thin film solar cells. We report on the results of manipulating the absorber/buffer interface between the chalcopyrite Cu(In,Ga)Se{sub 2} (CIGS) absorber and CdS or ZnS buffer by addition of a thin In based mixture layer. It is shown that the presence of thin In{sub x}(OH,S){sub y} at the CIGS absorber/CdS or ZnS buffer interfaces greatly improve the solar cell performances. The performances of CIGS cells using dual buffer layers composed of In{sub x}(OH,S){sub y}/CdS or In{sub x}(OH,S){sub y}/ZnS increased by 22.4% and 51.6%, as compared to the single and standard CdS or ZnS buffered cells, respectively.

  5. Impact of secondary barriers on copper-indium-gallium-selenide solar-cell operation

    Science.gov (United States)

    Pudov, Alexei O.

    Thin-film solar cells based on CuInSe2 (CIS) absorber with a band gap of Eg = 1.0 eV and also based on CuIn1-x GaxSe2 (CIGS) alloy absorbers with a band-gap range of Eg = 1.0--1.67 eV are investigated in this work. Intermediate "buffer" semiconductor layers in p-n junctions of CIGS solar cells often improve photodiode properties of the devices. The primary goal of the thesis is to study secondary barriers in the conduction band at the buffer/absorber interface, which may limit current transport and thus reduce the efficiency of the solar cells. The secondary goal is to explore alternative wide-bandgap buffers in CIGS cell structures. CIGS cells with standard CdS buffer layers, and alternative ZnS(O,OH) and InS(O,OH) buffer layers were studied. CdS/CuIn1-xGaxSe2 solar cells with variable Ga content have a range of conduction-band offsets (DeltaEc) in the junction from moderately positive (spike offsets) in CdS/CuInSe2 to moderately negative (cliff offsets) in CdS/CuGaSe 2. Moderate conduction-band spikes in CdS/CIS and low-Ga CdS/CIGS are expected to cause distortions in diode current-voltage (J-V) curves of such solar cells under "red" illumination (hnu < Eg(buffer)); no J-V distortions are expected for high-Ga CdS/CIGS with cliff offsets. These predictions were confirmed in experiments: the distortions were absent for cells with Eg above 1.2--1.3 eV, at which CdS/CIGS DeltaE c is near zero. Experiments and numerical simulations showed that one approach to reduce secondary barriers and J-V distortions in low-Ga high-spike cells is to thin the buffer layer(s). Blue photons (hnu above Eg(buffer)) in the solar spectrum induce photoconductivity in the otherwise compensated buffers, which also results in lowering of the secondary barriers. It was shown that CIGS cells with CdS, InS(O,OH), and ZnS(O,OH) buffers have a similar response to "blue" photons: J-V distortion, if present under red light, is reduced or entirely disappears with blue-light exposure within minutes

  6. Manufacturable CuIn(Ga)Se{sub 2}-based solar cells via development of co-sputtered CuInSe{sub 2} absorber layers

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Ingrid Eisgruber

    1999-03-20

    Yield and reproducibility remain issues in CuIn(Ga)Se{sub 2} (CIGS) photovoltaic module fabrication. While small-area cells (<1 cm{sup 2}) over 18% efficient have been reported, the best large-area manufactured devices (>1 ft{sup 2}) are 11% efficient with about 60% yield. If improvements in large-area manufacturing can accomplish 15% efficiency and 90% yield, the result is a doubling in throughput leading to a reduction in cost per watt of over 50%. The challenge now facing the photovoltaics industry is to bring the efficiencies of small-area cells and large-area industrial modules closer together and to raise manufacturing yields.

  7. VectorBase

    Data.gov (United States)

    U.S. Department of Health & Human Services — VectorBase is a Bioinformatics Resource Center for invertebrate vectors. It is one of four Bioinformatics Resource Centers funded by NIAID to provide web-based...

  8. Mobile Inquiry Based Learning

    NARCIS (Netherlands)

    Specht, Marcus

    2012-01-01

    Specht, M. (2012, 8 November). Mobile Inquiry Based Learning. Presentation given at the Workshop "Mobile inquiry-based learning" at the Mobile Learning Day 2012 at the Fernuniversität Hagen, Hagen, Germany.

  9. The ground based plan

    International Nuclear Information System (INIS)

    The paper presents a report of ''The Ground Based Plan'' of the United Kingdom Science and Engineering Research Council. The ground based plan is a plan for research in astronomy and planetary science by ground based techniques. The contents of the report contains a description of:- the scientific objectives and technical requirements (the basis for the Plan), the present organisation and funding for the ground based programme, the Plan, the main scientific features and the further objectives of the Plan. (U.K.)

  10. "Education-based Research"

    DEFF Research Database (Denmark)

    Degn Johansson, Troels

    This paper lays out a concept of education-based research-the production of research knowledge within the framework of tertiary design education-as an integration of problem-based learning and research-based education. This leads to a critique of reflective practice as the primary way to facilitate...... learning at this level, a discussion of the nature of design problems in the instrumentalist tradition, and some suggestions as to how design studies curricula may facilitate education-based research....

  11. Automated Testing Infrastructure and Result Comparison for Geodynamics Codes

    Science.gov (United States)

    Heien, E. M.; Kellogg, L. H.

    2013-12-01

    The geodynamics community uses a wide variety of codes on a wide variety of both software and hardware platforms to simulate geophysical phenomenon. These codes are generally variants of finite difference or finite element calculations involving Stokes flow or wave propagation. A significant problem is that codes of even low complexity will return different results depending on the platform due to slight differences in hardware, software, compiler, and libraries. Furthermore, changes to the codes during development may affect solutions in unexpected ways such that previously validated results are altered. The Computational Infrastructure for Geodynamics (CIG) is funded by the NSF to enhance the capabilities of the geodynamics community through software development. CIG has recently done extensive work in setting up an automated testing and result validation system based on the BaTLab system developed at the University of Wisconsin, Madison. This system uses 16 variants of Linux and Mac platforms on both 32 and 64-bit processors to test several CIG codes, and has also recently been extended to support testing on the XSEDE TACC (Texas Advanced Computing Center) Stampede cluster. In this work we overview the system design and demonstrate how automated testing and validation occurs and results are reported. We also examine several results from the system from different codes and discuss how changes in compilers and libraries affect the results. Finally we detail some result comparison tools for different types of output (scalar fields, velocity fields, seismogram data), and discuss within what margins different results can be considered equivalent.

  12. Nanosecond laser-induced selective removal of the active layer of CuInGaSe2 solar cells by stress-assisted ablation

    Science.gov (United States)

    Buzás, András; Geretovszky, Zsolt

    2012-06-01

    We demonstrate that laser pulses of nanosecond duration (λ=1064 nm, τ=25 ns, PRR =5 kHz) are capable of the clean removal of the CuInGaSe2 (CIGS) and ZnO:Al layers in the layer structure of chalcogenide-based solar cells, leaving the underlying Mo layer undamaged and producing excellent crater morphology. Our results prove that the material removal process is governed by the thermomechanical stress developing in the CIGS layer due to rapid laser heating. In the mechanical ablation of the active layer, three phenomena play a crucial role, namely, delamination, buckling, and fracture. Morphological and compositional analysis of the laser-processed areas is used to identify the experimental parameters where clean mechanical ablation can be achieved. Numerical calculations, performed in the comsol software environment, are also presented to complement the experimental tendencies and verify the proposed model. Our calculation proves the development of a stress distribution that drives the delamination of the CIGS and Mo layers. As the delamination front proceeds radially outward, the separation of the layers ceases in the colder outer regions according to the Griffith's criterion and defines the size of the craters produced afterwards. The free-standing chalcogenide layer continues to deform, and buckling results in a growing tensile stress at the perimeter of the delaminated area, where ultimately fracture will finalize the removal process and facilitate the clean ablation of the laser-irradiated area.

  13. Elemental depth profiling in Cu(In, Ga)Se 2 solar cells using micro-PIXE on a bevelled section

    Science.gov (United States)

    Spemann, D.; Otte, K.; Lorenz, M.; Butz, T.

    2005-04-01

    Cu(In, Ga)Se2 (CIGS) solar cells deposited on polyimide foils by the Solarion company in a web-coater based process using sputter and evaporation techniques were investigated in the ion beam laboratory LIPSION of the University of Leipzig by means of Rutherford Backscattering Spectrometry (RBS) and Particle Induced X-ray Emission (PIXE) using a 2.25 MeV proton microbeam. From these measurements the composition of the absorber as well as the lateral homogeneity and the film thicknesses of the individual layers of the solar cell could be determined under some reasonable assumptions. Quantitative depth profiling of the individual elements was performed by micro-PIXE measurements on a bevelled section of a CIGS solar cell prepared by ion beam etching. It revealed small concentration-depth-gradients for Cu, In, Ga and Se within the CIGS absorber layer. Furthermore, a remarkable amount of Cd from the overlying CdS buffer layer was found to be present in the absorber layer. Secondary Neutral Mass Spectrometry (SNMS) measurements were applied on the same samples for comparison.

  14. Stolen Base Physics

    Science.gov (United States)

    Kagan, David

    2013-01-01

    Few plays in baseball are as consistently close and exciting as the stolen base. While there are several studies of sprinting, the art of base stealing is much more nuanced. This article describes the motion of the base-stealing runner using a very basic kinematic model. The model will be compared to some data from a Major League game. The…

  15. Case-based reasoning

    CERN Document Server

    Kolodner, Janet

    1993-01-01

    Case-based reasoning is one of the fastest growing areas in the field of knowledge-based systems and this book, authored by a leader in the field, is the first comprehensive text on the subject. Case-based reasoning systems are systems that store information about situations in their memory. As new problems arise, similar situations are searched out to help solve these problems. Problems are understood and inferences are made by finding the closest cases in memory, comparing and contrasting the problem with those cases, making inferences based on those comparisons, and asking questions whe

  16. Synthetic Base Fluids

    Science.gov (United States)

    Brown, M.; Fotheringham, J. D.; Hoyes, T. J.; Mortier, R. M.; Orszulik, S. T.; Randles, S. J.; Stroud, P. M.

    The chemical nature and technology of the main synthetic lubricant base fluids is described, covering polyalphaolefins, alkylated aromatics, gas-to-liquid (GTL) base fluids, polybutenes, aliphatic diesters, polyolesters, polyalkylene glycols or PAGs and phosphate esters.Other synthetic lubricant base oils such as the silicones, borate esters, perfluoroethers and polyphenylene ethers are considered to have restricted applications due to either high cost or performance limitations and are not considered here.Each of the main synthetic base fluids is described for their chemical and physical properties, manufacture and production, their chemistry, key properties, applications and their implications when used in the environment.

  17. Monitoring Knowledge Base (MKB)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Monitoring Knowledge Base (MKB) is a compilation of emissions measurement and monitoring techniques associated with air pollution control devices, industrial...

  18. Soy-based polyols

    Science.gov (United States)

    Suppes, Galen; Lozada, Zueica; Lubguban, Arnold

    2013-06-25

    The invention provides processes for preparing soy-based oligomeric polyols or substituted oligomeric polyols, as well as urethane bioelasteromers comprising the oligomeric polyols or substituted oligomeric polyols.

  19. Gasification-based biomass

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2009-01-18

    The gasification-based biomass section of the Renewable Energy Technology Characterizations describes the technical and economic status of this emerging renewable energy option for electricity supply.

  20. XML-BASED REPRESENTATION

    Energy Technology Data Exchange (ETDEWEB)

    R. KELSEY

    2001-02-01

    For focused applications with limited user and use application communities, XML can be the right choice for representation. It is easy to use, maintain, and extend and enjoys wide support in commercial and research sectors. When the knowledge and information to be represented is object-based and use of that knowledge and information is a high priority, then XML-based representation should be considered. This paper discusses some of the issues involved in using XML-based representation and presents an example application that successfully uses an XML-based representation.

  1. Solution-processed solar cells based on environmentally friendly AgBiS2 nanocrystals

    Science.gov (United States)

    Bernechea, María; Miller, Nichole Cates; Xercavins, Guillem; So, David; Stavrinadis, Alexandros; Konstantatos, Gerasimos

    2016-08-01

    Solution-processed inorganic solar cells are a promising low-cost alternative to first-generation solar cells. Solution processing at low temperatures combined with the use of non-toxic and abundant elements can help minimize fabrication costs and facilitate regulatory acceptance. However, at present, there is no material that exhibits all these features while demonstrating promising efficiencies. Many of the candidates being explored contain toxic elements such as lead or cadmium (perovskites, PbS, CdTe and CdS(Se)) or scarce elements such as tellurium or indium (CdTe and CIGS(Se)/CIS). Others require high-temperature processes such as selenization or sintering, or rely on vacuum deposition techniques (Sb2S(Se)3, SnS and CZTS(Se)). Here, we present AgBiS2 nanocrystals as a non-toxic, earth-abundant material for high-performance, solution-processed solar cells fabricated under ambient conditions at low temperatures (≤100 °C). We demonstrate devices with a certified power conversion efficiency of 6.3%, with no hysteresis and a short-circuit current density of ∼22 mA cm‑2 for an active layer thickness of only ∼35 nm.

  2. Design and realization of transparent solar modules based on luminescent solar concentrators integrating nanostructured photonic crystals

    Science.gov (United States)

    Jiménez‐Solano, Alberto; Delgado‐Sánchez, José‐Maria; Calvo, Mauricio E.; Miranda‐Muñoz, José M.; Lozano, Gabriel; Sancho, Diego; Sánchez‐Cortezón, Emilio

    2015-01-01

    Abstract Herein, we present a prototype of a photovoltaic module that combines a luminescent solar concentrator integrating one‐dimensional photonic crystals and in‐plane CuInGaSe2 (CIGS) solar cells. Highly uniform and wide‐area nanostructured multilayers with photonic crystal properties were deposited by a cost‐efficient and scalable liquid processing amenable to large‐scale fabrication. Their role is to both maximize light absorption in the targeted spectral range, determined by the fluorophore employed, and minimize losses caused by emission at angles within the escape cone of the planar concentrator. From a structural perspective, the porous nature of the layers facilitates the integration with the thermoplastic polymers typically used to encapsulate and seal these modules. Judicious design of the module geometry, as well as of the optical properties of the dielectric mirrors employed, allows optimizing light guiding and hence photovoltaic performance while preserving a great deal of transparency. Optimized in‐plane designs like the one herein proposed are of relevance for building integrated photovoltaics, as ease of fabrication, long‐term stability and improved performance are simultaneously achieved. © 2015 The Authors. Progress in Photovoltaics: Research and Applications published by John Wiley & Sons Ltd. PMID:27656090

  3. Diffusion Based Photon Mapping

    DEFF Research Database (Denmark)

    Schjøth, Lars; Fogh Olsen, Ole; Sporring, Jon

    2007-01-01

    . To address this problem we introduce a novel photon mapping algorithm based on nonlinear anisotropic diffusion. Our algorithm adapts according to the structure of the photon map such that smoothing occurs along edges and structures and not across. In this way we preserve the important illumination features......, while eliminating noise. We call our method diffusion based photon mapping....

  4. Revolutionary Base Spurs Development

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    MAO Zedong’s Autumn Harvest Uprising spurred not only revolution but development and innovation among the masses. In October 1927, Mao Zedong led troops to Jinggang Mountain, establishing the first revolutionary base. During the 1960s, many young people went to work at Jinggang Mountain and devoted their youth to this revolutionary base. The open-minded and shrewd Tong

  5. Model-based geostatistics

    CERN Document Server

    Diggle, Peter J

    2007-01-01

    Model-based geostatistics refers to the application of general statistical principles of modeling and inference to geostatistical problems. This volume provides a treatment of model-based geostatistics and emphasizes on statistical methods and applications. It also features analyses of datasets from a range of scientific contexts.

  6. Arkansas' Disappearing Tax Base.

    Science.gov (United States)

    Schoppmeyer, Martin; Venters, Tommy

    State legislation that has contributed to the reduction of Arkansas' tax base is described in this paper. Amendment 59, adopted in 1980, has reduced the state tax base by millions of dollars. At the end of 1992, the majority of school districts have equalized their real, personal, and carrier and utility property. Act 34, the current foundation…

  7. Hydrogel based occlusion systems

    NARCIS (Netherlands)

    Stam, F.A.; Jackson, N.; Dubruel, P.; Adesanya, K.; Embrechts, A.; Mendes, E.; Neves, H.P.; Herijgers, P.; Verbrugghe, Y.; Shacham, Y.; Engel, L.; Krylov, V.

    2013-01-01

    A hydrogel based occlusion system, a method for occluding vessels, appendages or aneurysms, and a method for hydrogel synthesis are disclosed. The hydrogel based occlusion system includes a hydrogel having a shrunken and a swollen state and a delivery tool configured to deliver the hydrogel to a tar

  8. Secure base stations

    NARCIS (Netherlands)

    Bosch, Peter; Brusilovsky, Alec; McLellan, Rae; Mullender, Sape; Polakos, Paul

    2009-01-01

    With the introduction of the third generation (3G) Universal Mobile Telecommunications System (UMTS) base station router (BSR) and fourth generation (4G) base stations, such as the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) Evolved Node B (eNB), it has become important to se

  9. Profile Based Information Retrieval

    Directory of Open Access Journals (Sweden)

    Athar shaikh,

    2011-04-01

    Full Text Available This paper present Profile Based information retrieval system(PBIR. This system provide the user to register with it and based on the users registered areas of interest the system searches the related and efficient information form the world wide web using the technique of web text mining and arranges the unstructured data into structured format and present it to the user. This system also stores the previously searched data and based on users areas of interest and rating awarded to the interest by the user his profile will be updated at particular scheduled time.

  10. QuickBase

    CERN Document Server

    Conner, Nancy

    2007-01-01

    Ready to put Intuit's QuickBase to work? Our new Missing Manual shows you how to capture, modify, share, and manage data and documents with this web-based data-sharing program quickly and easily. No longer do you have to coordinate your team through a blizzard of emails or play frustrating games of "guess which document is the right one."QuickBase saves your organization time and money, letting you manage and share the information that makes your business tick: sales figures, project timelines, drafts of documents, purchase or work requests--whatever information you need to keep business flowi

  11. Data base management study

    Science.gov (United States)

    1976-01-01

    Data base management techniques and applicable equipment are described. Recommendations which will assist potential NASA data users in selecting and using appropriate data base management tools and techniques are presented. Classes of currently available data processing equipment ranging from basic terminals to large minicomputer systems were surveyed as they apply to the needs of potential SEASAT data users. Cost and capabilities projections for this equipment through 1985 were presented. A test of a typical data base management system was described, as well as the results of this test and recommendations to assist potential users in determining when such a system is appropriate for their needs. The representative system tested was UNIVAC's DMS 1100.

  12. Bases de dades relacionals

    OpenAIRE

    Villegas González, Daniel

    2016-01-01

    Les empreses de reclutament de personal han d¿afrontar una sèrie de reptes per les seves tasques diàries, pel gran volum de candidats per cobrir les necessitats del mercat de llocs de treball. RecruitCAT és una empresa de reclutament de personal que necessita gestionar la seva base de dades. El objectiu és dissenyar i implementar una base de dades per gestionar una empresa de reclutament de personal, assolint les tasques d¿estudi, plantejament teòric i els scripts de generació de la base d...

  13. Skull Base Anatomy.

    Science.gov (United States)

    Patel, Chirag R; Fernandez-Miranda, Juan C; Wang, Wei-Hsin; Wang, Eric W

    2016-02-01

    The anatomy of the skull base is complex with multiple neurovascular structures in a small space. Understanding all of the intricate relationships begins with understanding the anatomy of the sphenoid bone. The cavernous sinus contains the carotid artery and some of its branches; cranial nerves III, IV, VI, and V1; and transmits venous blood from multiple sources. The anterior skull base extends to the frontal sinus and is important to understand for sinus surgery and sinonasal malignancies. The clivus protects the brainstem and posterior cranial fossa. A thorough appreciation of the anatomy of these various areas allows for endoscopic endonasal approaches to the skull base.

  14. Design-Based Research

    DEFF Research Database (Denmark)

    Gynther, Karsten; Christensen, Ove; Petersen, Trine Brun

    2012-01-01

    I denne artikel introduceres Design Based Research for første gang på dansk i et videnskabeligt tidsskrift. Artiklen præsenterer de grundlæggende antagelser, som ligger til grund for Design Based Research-traditionen, og artiklen diskuterer de principper, som ligger til grund for gennemførelse af...... et DBR-forskningsprojekt. Med udgangspunkt i forsknings- og udviklingsprojektet ELYK: E-læring, Yderområder og Klyngedannelse, præsenteres den innovationsmodel, som projektet har udviklet med udgangspunkt i Design Based Research traditionen. ELYKs DBR innovationsmodel har vist sig effektiv i forhold...

  15. Lidar base specification

    Science.gov (United States)

    Heidemann, Hans Karl.

    2012-01-01

    In late 2009, a $14.3 million allocation from the “American Recovery and Reinvestment Act” for new light detection and ranging (lidar) elevation data prompted the U.S. Geological Survey (USGS) National Geospatial Program (NGP) to develop a common base specification for all lidar data acquired for The National Map. Released as a draft in 2010 and formally published in 2012, the USGS–NGP “Lidar Base Specification Version 1.0” (now Lidar Base Specification) was quickly embraced as the foundation for numerous state, county, and foreign country lidar specifications.

  16. Language-Based Learning Disabilities

    Science.gov (United States)

    ... Public / Speech, Language and Swallowing / Disorders and Diseases Language-Based Learning Disabilities (Reading, Spelling, and Writing) What ... a language-based learning disability ? What is a language-based learning disability? Language-based learning disabilities are ...

  17. Final report of CCQM-K129 Measurement of Mole Fractions of Cu, In, Ga and Se in Cu(In,Ga)Se2 Films

    Science.gov (United States)

    Kim, K. J.; Kim, A. S.; Jang, J. S.; Suh, J. K.; Wirth, T.; Unger, W.; Hodoroaba, V.-D.; Araujo, J. R.; Archanjo, B. S.; Galhardo, C. E.; Damasceno, J.; Achete, C. A.; Wang, H.; Wang, M.; Bennett, J.; Simon, D.; Kurokawa, A.; Terauchi, S.; Fujimoto, T.; Streeck, C.; Beckhoff, B.; Spencer, S.; Shard, A.

    2016-01-01

    CCQM key comparison K-129 for the quantitative analysis of Cu(In,Ga)Se2 (CIGS) films has been performed by the Surface Analysis Working Group (SAWG) of the Consultative Committee for Amount of Substance (CCQM). The objective of this key comparison is to compare the equivalency of the National Metrology Institutes (NMIs) and Designated Institutes (DIs) for the measurement of mole fractions of Cu, In, Ga and Se in a thin CIGS film. The measurand of this key comparison is the average mole fractions of Cu, In, Ga and Se of a test CIGS alloy film in the unit of mole fraction (mol/mol). Mole fraction with the metrological unit of % mol/mol can be practically converted to atomic fraction with the unit of at %. In this key comparison, a CIGS film with certified mole fractions was supplied as a reference specimen to determine the relative sensitivity factors (RSFs) of Cu, In, Ga and Se. The mole fractions of the reference specimen were certified by isotope dilution - inductively coupled plasma/mass spectrometry (ID-ICP/MS). A total number counting (TNC) method was recommended as a method to determine the signal intensities of the constituent elements acquired in the depth profiles by Secondary Ion Mass Spectrometry (SIMS), X-ray Photoelectron Spectroscopy (XPS) and Auger Electron Spectroscopy (AES). Seven NMIs and one DI participated in this key comparison. The mole fractions of the CIGS films were measured by depth profiling based-SIMS, AES and XPS. In this key comparison, the average degrees of equivalence uncertainties for Cu, In, Ga and Se are 0.0093 mol/mol, 0.0123 mol/mol, 0.0047 mol/mol and 0.0228 mol/mol, respectively. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  18. Cheboygan Vessel Base

    Data.gov (United States)

    Federal Laboratory Consortium — Cheboygan Vessel Base (CVB), located in Cheboygan, Michigan, is a field station of the USGS Great Lakes Science Center (GLSC). CVB was established by congressional...

  19. Noncommutative Involutive Bases

    CERN Document Server

    Evans, G A

    2006-01-01

    The theory of Groebner Bases originated in the work of Buchberger and is now considered to be one of the most important and useful areas of symbolic computation. A great deal of effort has been put into improving Buchberger's algorithm for computing a Groebner Basis, and indeed in finding alternative methods of computing Groebner Bases. Two of these methods include the Groebner Walk method and the computation of Involutive Bases. By the mid 1980's, Buchberger's work had been generalised for noncommutative polynomial rings by Bergman and Mora. This thesis provides the corresponding generalisation for Involutive Bases and (to a lesser extent) the Groebner Walk, with the main results being as follows. (1) Algorithms for several new noncommutative involutive divisions are given, including strong; weak; global and local divisions. (2) An algorithm for computing a noncommutative Involutive Basis is given. When used with one of the aforementioned involutive divisions, it is shown that this algorithm returns a noncom...

  20. Problem Based Learning

    DEFF Research Database (Denmark)

    de Graaff, Erik; Guerra, Aida

    Problem-Based Learning (PBL) is an innovative method to organize the learning process in such a way that the students actively engage in finding answers by themselves. During the past 40 years PBL has evolved and diversified resulting in a multitude in variations in models and practices. However...... model and in general problem based and project based learning. We apply the principle of teach as you preach. The poster aims to outline the visitors’ workshop programme showing the results of some recent evaluations......., the key principles remain the same everywhere. Graaff & Kolmos (2003) identify the main PBL principles as follows: 1. Problem orientation 2. Project organization through teams or group work 3. Participant-directed 4. Experiental learning 5. Activity-based learning 6. Interdisciplinary learning and 7...

  1. Mutually unbiased bases

    Indian Academy of Sciences (India)

    S Chaturvedi

    2002-08-01

    After a brief review of the notion of a full set of mutually unbiased bases in an -dimensional Hilbert space, we summarize the work of Wootters and Fields (W K Wootters and B C Fields, Ann. Phys. 191, 363 (1989)) which gives an explicit construction for such bases for the case = r, where is a prime. Further, we show how, by exploiting certain freedom in the Wootters–Fields construction, the task of explicitly writing down such bases can be simplified for the case when is an odd prime. In particular, we express the results entirely in terms of the character vectors of the cyclic group of order . We also analyse the connection between mutually unbiased bases and the representations of .

  2. Kelomehele preemia Baseli festivalil

    Index Scriptorium Estoniae

    2000-01-01

    Baselis festivalil "VIPER - International Festival for Film Video and New Media" tunnistati parimaks CD-ROMiks Gustav Deutschi/Anna Schimeki "Odysee today", netiprojektiks itaallaste "01.ORG", äramärkimispreemia - Raivo Kelomehe "Videoweaver"

  3. WormBase

    Data.gov (United States)

    U.S. Department of Health & Human Services — WormBase is an international consortium of biologists and computer scientists dedicated to providing the research community with accurate, current, accessible...

  4. ACTIVITY - BASED COSTING DESIGNING

    OpenAIRE

    Wioletta Skibiñska; Marta Kad³ubek

    2010-01-01

    The traditional costing system sometimes does not give accurate information about the consumption of different resources and the activities of the organisation. The activity-based costing system is an information-rich costing system which is more and more necessary for the success of many European companies. Base of designing and implementation of an ABC system in the enterprises are presented in the article.

  5. Participatory design based research

    DEFF Research Database (Denmark)

    Dau, Susanne; Bach Jensen, Louise; Falk, Lars

    2014-01-01

    This poster reveal how participatory design based research by the use of a CoED inspired creative process can be used for designing solutions to problems regarding students study activities outside campus.......This poster reveal how participatory design based research by the use of a CoED inspired creative process can be used for designing solutions to problems regarding students study activities outside campus....

  6. Layered nickel based superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Ronning, Filip [Los Alamos National Laboratory; Bauer, Eric D [Los Alamos National Laboratory; Park, Tuson [Los Alamos National Laboratory; Kurita, Nobuyuki [Los Alamos National Laboratory; Klimczuk, T [Los Alamos National Laboratory; Movshovich, R [Los Alamos National Laboratory; Thompson, J D [Los Alamos National Laboratory; Sefat, A S [ORNL; Mandrus, D [ORNL

    2009-01-01

    We review the properties of Ni-based superconductors which contain Ni{sub 2}X{sub 2} (X=As, P, Bi, Si, Ge, B) planes, a common structural element to the recently discovered FeAs superconductors. We also compare the properties ofthe Ni-and Fe-based systems from a perspective ofelectronic structure as well as structure-property relations.

  7. Hydrogel based occlusion systems

    OpenAIRE

    Stam, F.A.; Jackson, N.; Dubruel, P.; Adesanya, K.; Embrechts, A.; Mendes, E.; Neves, H.P.; Herijgers, P.; Verbrugghe, Y.; Shacham, Y; Engel, L.; Krylov, V.

    2013-01-01

    A hydrogel based occlusion system, a method for occluding vessels, appendages or aneurysms, and a method for hydrogel synthesis are disclosed. The hydrogel based occlusion system includes a hydrogel having a shrunken and a swollen state and a delivery tool configured to deliver the hydrogel to a target occlusion location. The hydrogel is configured to permanently occlude the target occlusion location in the swollen state. The hydrogel may be an electro-activated hydrogel (EAH) which could be ...

  8. Evidence-Based Development

    DEFF Research Database (Denmark)

    Hertzum, Morten; Simonsen, Jesper

    2004-01-01

    Systems development is replete with projects that represent substantial resource investments but result in systems that fail to meet users’ needs. Evidence-based development is an emerging idea intended to provide means for managing customer-vendor relationships and working systematically toward...... and electronic patient records for diabetes patients, this paper reports research in progress regarding the prospects and pitfalls of evidence-based development....

  9. Computer-based simulations

    OpenAIRE

    Antonoaie, C.; Antonoaie, N.

    2010-01-01

    A computer-based simulation replicates an environment through a computer program designed to consider multiple variables, interactions, and system constraints. Computer-based simulation is used in organization studies to model human social systems to better understand the dynamics between individual and group behaviours.These methods advance organization studies research in many ways. They can be used for extrapolating theory, validating hypotheses, or revealing emergent behaviour. Simulation...

  10. DSP Based Waveform Generator

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The DSP Based Waveform Generator is used for CSR Control system to control special controlled objects, such as the pulsed power supply for magnets, RF system, injection and extraction synchronization, global CSR synchronization etc. This intelligent controller based on 4800 MIPS DSP and 256M SDRAM technology will supply highly stable and highly accurate reference waveform used by the power supply of magnets. The specifications are as follows:

  11. Compression-based similarity

    OpenAIRE

    Vitányi, Paul

    2011-01-01

    First we consider pair-wise distances for literal objects consisting of finite binary files. These files are taken to contain all of their meaning, like genomes or books. The distances are based on compression of the objects concerned, normalized, and can be viewed as similarity distances. Second, we consider pair-wise distances between names of objects, like "red" or "christianity." In this case the distances are based on searches of the Internet. Such a search can be performed by any search...

  12. REST based mobile applications

    Science.gov (United States)

    Rambow, Mark; Preuss, Thomas; Berdux, Jörg; Conrad, Marc

    2008-02-01

    Simplicity is the major advantage of REST based webservices. Whereas SOAP is widespread in complex, security sensitive business-to-business aplications, REST is widely used for mashups and end-user centric applicatons. In that context we give an overview of REST and compare it to SOAP. Furthermore we apply the GeoDrawing application as an example for REST based mobile applications and emphasize on pros and cons for the use of REST in mobile application scenarios.

  13. LDEF materials data bases

    Science.gov (United States)

    Funk, Joan G.; Strickland, John W.; Davis, John M.

    1993-01-01

    The Long Duration Exposure Facility (LDEF) and the accompanying experiments were composed of and contained a wide variety of materials representing the largest collection of materials flown in low Earth orbit (LEO) and retrieved for ground based analysis to date. The results and implications of the mechanical, thermal, optical, and electrical data from these materials are the foundation on which future LEO space missions will be built. The LDEF Materials Special Investigation Group (MSIG) has been charged with establishing and developing data bases to document these materials and their performance to assure not only that the data are archived for future generations but also that the data are available to the spacecraft user community in an easily accessed, user-friendly form. This paper discusses the format and content of the three data bases developed or being developed to accomplish this task. The hardware and software requirements for each of these three data bases are discussed along with current availability of the data bases. This paper also serves as a user's guide to the MAPTIS LDEF Materials Data Base.

  14. Noncommutative Involutive Bases

    Science.gov (United States)

    Alun Evans, Gareth

    2006-02-01

    The theory of Groebner Bases originated in the work of Buchberger and is now considered to be one of the most important and useful areas of symbolic computation. A great deal of effort has been put into improving Buchberger's algorithm for computing a Groebner Basis, and indeed in finding alternative methods of computing Groebner Bases. Two of these methods include the Groebner Walk method and the computation of Involutive Bases. By the mid 1980's, Buchberger's work had been generalised for noncommutative polynomial rings by Bergman and Mora. This thesis provides the corresponding generalisation for Involutive Bases and (to a lesser extent) the Groebner Walk, with the main results being as follows. (1) Algorithms for several new noncommutative involutive divisions are given, including strong; weak; global and local divisions. (2) An algorithm for computing a noncommutative Involutive Basis is given. When used with one of the aforementioned involutive divisions, it is shown that this algorithm returns a noncommutative Groebner Basis on termination. (3) An algorithm for a noncommutative Groebner Walk is given, in the case of conversion between two harmonious monomial orderings. It is shown that this algorithm generalises to give an algorithm for performing a noncommutative Involutive Walk, again in the case of conversion between two harmonious monomial orderings. (4) Two new properties of commutative involutive divisions are introduced (stability and extendibility), respectively ensuring the termination of the Involutive Basis algorithm and the applicability (under certain conditions) of homogeneous methods of computing Involutive Bases.

  15. On mutually unbiased bases

    CERN Document Server

    Durt, Thomas; Bengtsson, Ingemar; Zyczkowski, Karol \\

    2010-01-01

    Mutually unbiased bases for quantum degrees of freedom are central to all theoretical investigations and practical exploitations of complementary properties. Much is known about mutually unbiased bases, but there are also a fair number of important questions that have not been answered in full as yet. In particular, one can find maximal sets of ${N+1}$ mutually unbiased bases in Hilbert spaces of prime-power dimension ${N=p^\\m}$, with $p$ prime and $\\m$ a positive integer, and there is a continuum of mutually unbiased bases for a continuous degree of freedom, such as motion along a line. But not a single example of a maximal set is known if the dimension is another composite number ($N=6,10,12,...$). In this review, we present a unified approach in which the basis states are labeled by numbers ${0,1,2,...,N-1}$ that are both elements of a Galois field and ordinary integers. This dual nature permits a compact systematic construction of maximal sets of mutually unbiased bases when they are known to exist but th...

  16. Evidence based practice

    DEFF Research Database (Denmark)

    Hjørland, Birger

    2011-01-01

    Evidence-based practice (EBP) is an influential interdisciplinary movement that originated in medicine as evidence-based medicine (EBM) about 1992. EBP is of considerable interest to library and information science (LIS) because it focuses on a thorough documentation of the basis for the decision...... is that practitioners lose their autonomy, that the understanding of theory and of underlying mechanisms is weakened, and that the concept of evidence is too narrow in the empiricist tradition. In this article, it is suggested that we should speak of “research-based practice” rather than EBP, because this term is open...... to more fruitful epistemologies and provides a broader understanding of evidence.The focus on scientific argumentation in EBP is an important contribution from EBP to LIS, which is long overdue, but parts of the underlying epistemological assumptions should be replaced: EBP is too narrow, too formalist...

  17. Nitramine Double Base Propellants

    Directory of Open Access Journals (Sweden)

    M. M. Bhalerao

    1996-10-01

    Full Text Available This review paper broadly covers the studies conducted on nitramine double base (DB propellants, particularly in the field of formulations, evaluation, catalysis and combustion mechanism . Addition of RDX and HMX in double base matrix shows relatively low burn rates and high paper index values. Further, the burn rate of this class of propellants enhances in the presence of energetic binders/plasticisers like glycidyl azide polymer. This paper also discusses the combustion mechanism of HMX/RDX-based DB propellants, especially in the presence of catalytic salts. As scanty data is available on extruded nitramine DB propellants, further work is needed in the field of formulation as well as evaluation with a view to generate exhaustive data.

  18. Classification of base sequences

    CERN Document Server

    Djokovic, Dragomir Z

    2010-01-01

    Base sequences BS(n+1,n) are quadruples of {1,-1}-sequences (A;B;C;D), with A and B of length n+1 and C and D of length n, such that the sum of their nonperiodic autocorrelation functions is a delta-function. The base sequence conjecture, asserting that BS(n+1,n) exist for all n, is stronger than the famous Hadamard matrix conjecture. We introduce a new definition of equivalence for base sequences BS(n+1,n) and construct a canonical form. By using this canonical form, we have enumerated the equivalence classes of BS(n+1,n) for n <= 30. Due to excessive size of the equivalence classes, the tables in the paper cover only the cases n <= 12.

  19. Cantilever Based Mass Sensing

    DEFF Research Database (Denmark)

    Dohn, Søren

    2007-01-01

    Cantilever based mass sensors utilize that a change in vibrating mass will cause a change in the resonant frequency. This can be used for very accurate sensing of adsorption and desorption processes on the cantilever surface. The change in resonant frequency caused by a single molecule depends...... on various parameters including the vibrating mass of the cantilever and the frequency at which it vibrates. The minimum amount of molecules detectable is highly dependent on the noise of the system as well as the method of readout. The aim of this Ph.D. thesis has been twofold: To develop a readout method...... suitable for a portable device and to investigate the possibility of enhancing the functionality and sensitivity of cantilever based mass sensors. A readout method based on the hard contact between the cantilever and a biased electrode placed in close proximity to the cantilever is proposed. The viability...

  20. Inkjet-based micromanufacturing

    CERN Document Server

    Korvink, Jan G; Shin, Dong-Youn; Brand, Oliver; Fedder, Gary K; Hierold, Christofer; Tabata, Osamu

    2012-01-01

    Inkjet-based Micromanufacturing Inkjet technology goes way beyond putting ink on paper: it enables simpler, faster and more reliable manufacturing processes in the fields of micro- and nanotechnology. Modern inkjet heads are per se precision instruments that deposit droplets of fluids on a variety of surfaces in programmable, repeating patterns, allowing, after suitable modifications and adaptations, the manufacturing of devices such as thin-film transistors, polymer-based displays and photovoltaic elements. Moreover, inkjet technology facilitates the large-scale production of flexible RFID tr

  1. Video-based rendering

    CERN Document Server

    Magnor, Marcus A

    2005-01-01

    Driven by consumer-market applications that enjoy steadily increasing economic importance, graphics hardware and rendering algorithms are a central focus of computer graphics research. Video-based rendering is an approach that aims to overcome the current bottleneck in the time-consuming modeling process and has applications in areas such as computer games, special effects, and interactive TV. This book offers an in-depth introduction to video-based rendering, a rapidly developing new interdisciplinary topic employing techniques from computer graphics, computer vision, and telecommunication en

  2. Diffusion Based Photon Mapping

    DEFF Research Database (Denmark)

    Schjøth, Lars; Olsen, Ole Fogh; Sporring, Jon

    2006-01-01

    . To address this problem we introduce a novel photon mapping algorithm based on nonlinear anisotropic diffusion. Our algorithm adapts according to the structure of the photon map such that smoothing occurs along edges and structures and not across. In this way we preserve the important illumination features......Density estimation employed in multi-pass global illumination algorithms give cause to a trade-off problem between bias and noise. The problem is seen most evident as blurring of strong illumination features. In particular this blurring erodes fine structures and sharp lines prominent in caustics......, while eliminating noise. We call our method diffusion based photon mapping....

  3. Identity-based encryption

    CERN Document Server

    Chatterjee, Sanjit

    2011-01-01

    Identity Based Encryption (IBE) is a type of public key encryption and has been intensely researched in the past decade. Identity-Based Encryption summarizes the available research for IBE and the main ideas that would enable users to pursue further work in this area. This book will also cover a brief background on Elliptic Curves and Pairings, security against chosen Cipher text Attacks, standards and more. Advanced-level students in computer science and mathematics who specialize in cryptology, and the general community of researchers in the area of cryptology and data security will find Ide

  4. Animation-based Sketching

    DEFF Research Database (Denmark)

    Vistisen, Peter

    This thesis is based on the results of a three-year long PhD-study at the Department of Communication and Psychology at Aalborg University. The thesis consist of five original papers, a book manuscript, as well as a linking text with the thesis’ research questions, research design, and summary...... experiments has been carried out, applying animation-based sketching in various contexts and at varying points in the design process. In the studies, I evaluate the viability of the approach, the practical integration into the design process, and map how consensus between stakeholders in design can...

  5. Domain based metering

    OpenAIRE

    Párhonyi, Robert; Beijnum, van, Bert-Jan

    2000-01-01

    In the last two years, there is a gaining interest in usage based accounting for the Internet. One of the driving forces for this growing interest is the progress being made in providing some form of quality assurance in IP packet forwarding. One of the key processes in an accounting system is metering, gathering of network usage parameters on which the accounting is or can be based. In this paper are addressed issues that are potentially of interest in Internet accounting. One of these issue...

  6. Game-Based Teaching

    DEFF Research Database (Denmark)

    Hanghøj, Thorkild

    2013-01-01

    This chapter outlines theoretical and empirical perspectives on how Game-Based Teaching can be integrated within the context of formal schooling. Initially, this is done by describing game scenarios as models for possible actions that need to be translated into curricular knowledge practices......, pedagogical knowledge practices, and everyday knowledge practices. Secondly, the chapter emphasizes how teachers must be able to shift back and forth between various interactional roles in order to facilitate game scenarios. Finally, a discussion is presented on how teachers choose different pedagogical...... approaches to game-based teaching, which may or may not correspond with the pedagogical models of particular games....

  7. PROJECT-BASES RISK MANAGEMENT

    OpenAIRE

    Andrei Sandu

    2010-01-01

    The project-bases concept is presented. There are defined operations on project-bases. The software developed for project-bases management is analyzed based in its structure and functionality. A series of criteria of structuring risks is listed are tailored for project-bases management. Next there are suggested solutions of mitigating risks by maintaining efficiency within acceptable thresholds.

  8. Internet based benchmarking

    DEFF Research Database (Denmark)

    Bogetoft, Peter; Nielsen, Kurt

    2005-01-01

    We discuss the design of interactive, internet based benchmarking using parametric (statistical) as well as nonparametric (DEA) models. The user receives benchmarks and improvement potentials. The user is also given the possibility to search different efficiency frontiers and hereby to explore...

  9. BASE - Progress Report 2015

    CERN Document Server

    Ulmer, S; Mooser, A; Sellner, S; Nagahama, H; Higuchi, T; Borchert, M; Schneider, G; Tanaka, T; Blaum, K; Matsuda, Y; Ospelkaus, C; Quint, W; Walz, J; Yamazaki, Y; CERN. Geneva. SPS and PS Experiments Committee; SPSC

    2016-01-01

    The BASE collaboration aims at high-precision comparisons of the fundamental properties of the proton and the antiproton, namely, the magnetic g-factors as well as the charge-to-mass ratios of the particles. This annual report summarizes the achievements made in CERN's 2015 antiproton run.

  10. Model-based consensus

    NARCIS (Netherlands)

    Boumans, Marcel

    2014-01-01

    The aim of the rational-consensus method is to produce “rational consensus”, that is, “mathematical aggregation”, by weighing the performance of each expert on the basis of his or her knowledge and ability to judge relevant uncertainties. The measurement of the performance of the experts is based on

  11. Model-based consensus

    NARCIS (Netherlands)

    M. Boumans

    2014-01-01

    The aim of the rational-consensus method is to produce "rational consensus", that is, "mathematical aggregation", by weighing the performance of each expert on the basis of his or her knowledge and ability to judge relevant uncertainties. The measurement of the performance of the experts is based on

  12. Centroid Based Text Clustering

    Directory of Open Access Journals (Sweden)

    Priti Maheshwari

    2010-09-01

    Full Text Available Web mining is a burgeoning new field that attempts to glean meaningful information from natural language text. Web mining refers generally to the process of extracting interesting information and knowledge from unstructured text. Text clustering is one of the important Web mining functionalities. Text clustering is the task in which texts are classified into groups of similar objects based on their contents. Current research in the area of Web mining is tacklesproblems of text data representation, classification, clustering, information extraction or the search for and modeling of hidden patterns. In this paper we propose for mining large document collections it is necessary to pre-process the web documents and store the information in a data structure, which is more appropriate for further processing than a plain web file. In this paper we developed a php-mySql based utility to convert unstructured web documents into structured tabular representation by preprocessing, indexing .We apply centroid based web clustering method on preprocessed data. We apply three methods for clustering. Finally we proposed a method that can increase accuracy based on clustering ofdocuments.

  13. Performance based fault diagnosis

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik

    2002-01-01

    Different aspects of fault detection and fault isolation in closed-loop systems are considered. It is shown that using the standard setup known from feedback control, it is possible to formulate fault diagnosis problems based on a performance index in this general standard setup. It is also shown...

  14. 80537 based distance relay

    DEFF Research Database (Denmark)

    Pedersen, Knud Ole Helgesen

    1999-01-01

    A method for implementing a digital distance relay in the power system is described.Instructions are given on how to program this relay on a 80537 based microcomputer system.The problem is used as a practical case study in the course 53113: Micocomputer applications in the power system.The relay...

  15. REST based service composition

    DEFF Research Database (Denmark)

    Grönvall, Erik; Ingstrup, Mads; Pløger, Morten;

    2011-01-01

    This paper presents an ongoing work developing and testing a Service Composition framework based upon the REST architecture named SECREST. A minimalistic approach have been favored instead of a creating a complete infrastructure. One focus has been on the system's interaction model. Indeed, an ai...

  16. Aptamer-based nanobiosensors.

    Science.gov (United States)

    Kim, Yeon Seok; Raston, Nurul Hanun Ahmad; Gu, Man Bock

    2016-02-15

    It has been more than two decades since aptamer and the systematic evolution of ligands by exponential enrichment (SELEX) method were discovered by Larry Gold and Andrew Ellington in 1990, respectively. Based on the various advantages of aptamers, they have become a potent rival of antibodies in therapeutics and bio-analysis. Especially, the recent advances in aptamer biosensor application are remarkable due to its intrinsic properties of aptamers as nucleic acids and target induced conformational changes, in addition to the introduction of graphene oxide-based easy and simple immobilization-free screening method even for dual aptamers. In addition, the incorporation of various nanomaterials such as metallic nanoparticles, carbon materials, and functional nanospheres in aptasensors has facilitated the improvement of analytical performance and commercial application of aptasensors. In this review, recent prominent reports on aptasensors utilizing nanomaterials were introduced to understand the principle of aptamer-based biosensors and provide an insight for new strategies of aptasensors and the application of various nanomaterials. The perspective on aptamer-based biosensors and diagnostics was also discussed in view of technology and market. PMID:26139320

  17. Protein Crystal Based Nanomaterials

    Science.gov (United States)

    Bell, Jeffrey A.; VanRoey, Patrick

    2001-01-01

    This is the final report on a NASA Grant. It concerns a description of work done, which includes: (1) Protein crystals cross-linked to form fibers; (2) Engineering of protein to favor crystallization; (3) Better knowledge-based potentials for protein-protein contacts; (4) Simulation of protein crystallization.

  18. XML Based UIScript

    Institute of Scientific and Technical Information of China (English)

    CAI Bin; LIAO Jian-xin; SHEN Qi-wei

    2004-01-01

    In this paper, after the analyzing the UIScript mechanism in intelligent peripheral, a new approach of XML-based UIScript is put forward. The related issues such as the design of UIScript language, the execution environment and its relationship with other script languages are discussed.

  19. Project-Based Science

    Science.gov (United States)

    Krajcik, Joe

    2015-01-01

    Project-based science is an exciting way to teach science that aligns with the "Next Generation Science Standards" ("NGSS"). By focusing on core ideas along with practices and crosscutting concepts, classrooms become learning environments where teachers and students engage in science by designing and carrying out…

  20. Acid-Base Homeostasis.

    Science.gov (United States)

    Hamm, L Lee; Nakhoul, Nazih; Hering-Smith, Kathleen S

    2015-12-01

    Acid-base homeostasis and pH regulation are critical for both normal physiology and cell metabolism and function. The importance of this regulation is evidenced by a variety of physiologic derangements that occur when plasma pH is either high or low. The kidneys have the predominant role in regulating the systemic bicarbonate concentration and hence, the metabolic component of acid-base balance. This function of the kidneys has two components: reabsorption of virtually all of the filtered HCO3(-) and production of new bicarbonate to replace that consumed by normal or pathologic acids. This production or generation of new HCO3(-) is done by net acid excretion. Under normal conditions, approximately one-third to one-half of net acid excretion by the kidneys is in the form of titratable acid. The other one-half to two-thirds is the excretion of ammonium. The capacity to excrete ammonium under conditions of acid loads is quantitatively much greater than the capacity to increase titratable acid. Multiple, often redundant pathways and processes exist to regulate these renal functions. Derangements in acid-base homeostasis, however, are common in clinical medicine and can often be related to the systems involved in acid-base transport in the kidneys.

  1. Problem-Based Learning

    Science.gov (United States)

    Allen, Deborah E.; Donham, Richard S.; Bernhardt, Stephen A.

    2011-01-01

    In problem-based learning (PBL), students working in collaborative groups learn by resolving complex, realistic problems under the guidance of faculty. There is some evidence of PBL effectiveness in medical school settings where it began, and there are numerous accounts of PBL implementation in various undergraduate contexts, replete with…

  2. ISFET based enzyme sensors

    NARCIS (Netherlands)

    Schoot, van der Bart H.; Bergveld, Piet

    1987-01-01

    This paper reviews the results that have been reported on ISFET based enzyme sensors. The most important improvement that results from the application of ISFETs instead of glass membrane electrodes is in the method of fabrication. Problems with regard to the pH dependence of the response and the dyn

  3. Surfel Based Geometry Resonstruction

    DEFF Research Database (Denmark)

    Andersen, Vedrana; Aanæs, Henrik; Bærentzen, Jakob Andreas

    2010-01-01

    We propose a method for retrieving a piecewise smooth surface from noisy data. In data acquired by a scanning process sampled points are almost never on the discontinuities making reconstruction of surfaces with sharp features difficult. Our method is based on a Markov Random Field (MRF) formulat...

  4. Exposure to electronic cigarettes impairs pulmonary anti-bacterial and anti-viral defenses in a mouse model.

    Science.gov (United States)

    Sussan, Thomas E; Gajghate, Sachin; Thimmulappa, Rajesh K; Ma, Jinfang; Kim, Jung-Hyun; Sudini, Kuladeep; Consolini, Nicola; Cormier, Stephania A; Lomnicki, Slawo; Hasan, Farhana; Pekosz, Andrew; Biswal, Shyam

    2015-01-01

    Electronic cigarettes (E-cigs) have experienced sharp increases in popularity over the past five years due to many factors, including aggressive marketing, increased restrictions on conventional cigarettes, and a perception that E-cigs are healthy alternatives to cigarettes. Despite this perception, studies on health effects in humans are extremely limited and in vivo animal models have not been generated. Presently, we determined that E-cig vapor contains 7 x 10(11) free radicals per puff. To determine whether E-cig exposure impacts pulmonary responses in mice, we developed an inhalation chamber for E-cig exposure. Mice that were exposed to E-cig vapor contained serum cotinine concentrations that are comparable to human E-cig users. E-cig exposure for 2 weeks produced a significant increase in oxidative stress and moderate macrophage-mediated inflammation. Since, COPD patients are susceptible to bacterial and viral infections, we tested effects of E-cigs on immune response. Mice that were exposed to E-cig vapor showed significantly impaired pulmonary bacterial clearance, compared to air-exposed mice, following an intranasal infection with Streptococcus pneumonia. This defective bacterial clearance was partially due to reduced phagocytosis by alveolar macrophages from E-cig exposed mice. In response to Influenza A virus infection, E-cig exposed mice displayed increased lung viral titers and enhanced virus-induced illness and mortality. In summary, this study reports a murine model of E-cig exposure and demonstrates that E-cig exposure elicits impaired pulmonary anti-microbial defenses. Hence, E-cig exposure as an alternative to cigarette smoking must be rigorously tested in users for their effects on immune response and susceptibility to bacterial and viral infections. PMID:25651083

  5. Exposure to electronic cigarettes impairs pulmonary anti-bacterial and anti-viral defenses in a mouse model.

    Directory of Open Access Journals (Sweden)

    Thomas E Sussan

    Full Text Available Electronic cigarettes (E-cigs have experienced sharp increases in popularity over the past five years due to many factors, including aggressive marketing, increased restrictions on conventional cigarettes, and a perception that E-cigs are healthy alternatives to cigarettes. Despite this perception, studies on health effects in humans are extremely limited and in vivo animal models have not been generated. Presently, we determined that E-cig vapor contains 7 x 10(11 free radicals per puff. To determine whether E-cig exposure impacts pulmonary responses in mice, we developed an inhalation chamber for E-cig exposure. Mice that were exposed to E-cig vapor contained serum cotinine concentrations that are comparable to human E-cig users. E-cig exposure for 2 weeks produced a significant increase in oxidative stress and moderate macrophage-mediated inflammation. Since, COPD patients are susceptible to bacterial and viral infections, we tested effects of E-cigs on immune response. Mice that were exposed to E-cig vapor showed significantly impaired pulmonary bacterial clearance, compared to air-exposed mice, following an intranasal infection with Streptococcus pneumonia. This defective bacterial clearance was partially due to reduced phagocytosis by alveolar macrophages from E-cig exposed mice. In response to Influenza A virus infection, E-cig exposed mice displayed increased lung viral titers and enhanced virus-induced illness and mortality. In summary, this study reports a murine model of E-cig exposure and demonstrates that E-cig exposure elicits impaired pulmonary anti-microbial defenses. Hence, E-cig exposure as an alternative to cigarette smoking must be rigorously tested in users for their effects on immune response and susceptibility to bacterial and viral infections.

  6. Problem Based Game Design

    DEFF Research Database (Denmark)

    Reng, Lars; Schoenau-Fog, Henrik

    2011-01-01

    At Aalborg University’s department of Medialogy, we are utilizing the Problem Based Learning method to encourage students to solve game design problems by pushing the boundaries and designing innovative games. This paper is concerned with describing this method, how students employ it in various ...... projects and how they learn to analyse, design, and develop for innovation by using it. We will present various cases to exemplify the approach and focus on how the method engages students and aspires for innovation in digital entertainment and games.......At Aalborg University’s department of Medialogy, we are utilizing the Problem Based Learning method to encourage students to solve game design problems by pushing the boundaries and designing innovative games. This paper is concerned with describing this method, how students employ it in various...

  7. Trajectory Based Traffic Analysis

    DEFF Research Database (Denmark)

    Krogh, Benjamin Bjerre; Andersen, Ove; Lewis-Kelham, Edwin;

    2013-01-01

    We present the INTRA system for interactive path-based traffic analysis. The analyses are developed in collaboration with traffic researchers and provide novel insights into conditions such as congestion, travel-time, choice of route, and traffic-flow. INTRA supports interactive point-and-click a......We present the INTRA system for interactive path-based traffic analysis. The analyses are developed in collaboration with traffic researchers and provide novel insights into conditions such as congestion, travel-time, choice of route, and traffic-flow. INTRA supports interactive point......-and-click analysis, due to a novel and efficient indexing structure. With the web-site daisy.aau.dk/its/spqdemo/we will demonstrate several analyses, using a very large real-world data set consisting of 1.9 billion GPS records (1.5 million trajectories) recorded from more than 13000 vehicles, and touching most...

  8. Spintronics-based computing

    CERN Document Server

    Prenat, Guillaume

    2015-01-01

    This book provides a comprehensive introduction to spintronics-based computing for the next generation of ultra-low power/highly reliable logic, which is widely considered a promising candidate to replace conventional, pure CMOS-based logic. It will cover aspects from device to system-level, including magnetic memory cells, device modeling, hybrid circuit structure, design methodology, CAD tools, and technological integration methods. This book is accessible to a variety of readers and little or no background in magnetism and spin electronics are required to understand its content.  The multidisciplinary team of expert authors from circuits, devices, computer architecture, CAD and system design reveal to readers the potential of spintronics nanodevices to reduce power consumption, improve reliability and enable new functionality.  .

  9. Maintaining Relationship Based Procurement

    Directory of Open Access Journals (Sweden)

    Peter Davis

    2012-11-01

    Full Text Available Alliance and relationship projects are increasingin number and represent a large pool of work. Tobe successful relationship style contracts dependon soft-dollar factors, particularly the participants'ability to work together within an agreedframework, generally they are not based on lowbid tendering. Participants should be prepared todo business in an open environment based ontrust and mutually agreed governance. Theresearch evaluates relationship maintenance inthe implementation phase of constructionalliances - a particular derivative of relationshipstyle contracts. To determine the factors thatcontribute to relationship maintenance forty-nineexperienced Australian alliance projectmanagers were interviewed. The main findingswere; the development of relationships early inthe project form building blocks of success fromwhich relationships are maintained and projectvalue added; quality facilitation plays animportant part in relationship maintenance and ahybrid organisation created as a result of alliancedevelopment overcomes destructiveorganisational boundaries. Relationshipmaintenance is integral to alliance project controland failure to formalise it and pay attention toprocess and past outcomes will undermine analliance project's potential for success.

  10. Conducting Polymer Based Nanobiosensors

    Directory of Open Access Journals (Sweden)

    Chul Soon Park

    2016-06-01

    Full Text Available In recent years, conducting polymer (CP nanomaterials have been used in a variety of fields, such as in energy, environmental, and biomedical applications, owing to their outstanding chemical and physical properties compared to conventional metal materials. In particular, nanobiosensors based on CP nanomaterials exhibit excellent performance sensing target molecules. The performance of CP nanobiosensors varies based on their size, shape, conductivity, and morphology, among other characteristics. Therefore, in this review, we provide an overview of the techniques commonly used to fabricate novel CP nanomaterials and their biosensor applications, including aptasensors, field-effect transistor (FET biosensors, human sense mimicking biosensors, and immunoassays. We also discuss prospects for state-of-the-art nanobiosensors using CP nanomaterials by focusing on strategies to overcome the current limitations.

  11. Content Based Video Retrieval

    Directory of Open Access Journals (Sweden)

    B.V.Patel

    2012-11-01

    Full Text Available Content based video retrieval is an approach for facilitating the searching and browsing of large image collections over World Wide Web. In this approach, video analysis is conducted on low level visual properties extracted from video frame. We believed that in order to create an effective video retrieval system, visual perception must be taken into account. We conjectured that a technique which employs multiple features for indexing and retrieval would be more effective in the discrimination and search tasks of videos. In order to validate this claim, content based indexing and retrieval systems were implemented using color histogram, various texture features and other approaches. Videos were stored in Oracle 9i Database and a user study measured correctness of response.

  12. Graphene-based electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Xiao; Zeng, Zhiyuan; Fan, Zhanxi; Liu, Juqing; Zhang, Hua [School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798 (Singapore)

    2012-11-27

    Graphene, the thinnest two dimensional carbon material, has become the subject of intensive investigation in various research fields because of its remarkable electronic, mechanical, optical and thermal properties. Graphene-based electrodes, fabricated from mechanically cleaved graphene, chemical vapor deposition (CVD) grown graphene, or massively produced graphene derivatives from bulk graphite, have been applied in a broad range of applications, such as in light emitting diodes, touch screens, field-effect transistors, solar cells, supercapacitors, batteries, and sensors. In this Review, after a short introduction to the properties and synthetic methods of graphene and its derivatives, we will discuss the importance of graphene-based electrodes, their fabrication techniques, and application areas. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Graphene-based electrodes.

    Science.gov (United States)

    Huang, Xiao; Zeng, Zhiyuan; Fan, Zhanxi; Liu, Juqing; Zhang, Hua

    2012-11-27

    Graphene, the thinnest two dimensional carbon material, has become the subject of intensive investigation in various research fields because of its remarkable electronic, mechanical, optical and thermal properties. Graphene-based electrodes, fabricated from mechanically cleaved graphene, chemical vapor deposition (CVD) grown graphene, or massively produced graphene derivatives from bulk graphite, have been applied in a broad range of applications, such as in light emitting diodes, touch screens, field-effect transistors, solar cells, supercapacitors, batteries, and sensors. In this Review, after a short introduction to the properties and synthetic methods of graphene and its derivatives, we will discuss the importance of graphene-based electrodes, their fabrication techniques, and application areas. PMID:22927209

  14. Sparse approximation with bases

    CERN Document Server

    2015-01-01

    This book systematically presents recent fundamental results on greedy approximation with respect to bases. Motivated by numerous applications, the last decade has seen great successes in studying nonlinear sparse approximation. Recent findings have established that greedy-type algorithms are suitable methods of nonlinear approximation in both sparse approximation with respect to bases and sparse approximation with respect to redundant systems. These insights, combined with some previous fundamental results, form the basis for constructing the theory of greedy approximation. Taking into account the theoretical and practical demand for this kind of theory, the book systematically elaborates a theoretical framework for greedy approximation and its applications.  The book addresses the needs of researchers working in numerical mathematics, harmonic analysis, and functional analysis. It quickly takes the reader from classical results to the latest frontier, but is written at the level of a graduate course and do...

  15. Knowledge based maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Sturm, A. [Hamburgische Electacitaets-Werke AG Hamburg (Germany)

    1997-12-31

    The establishment of maintenance strategies is of crucial significance for the reliability of a plant and the economic efficiency of maintenance measures. Knowledge about the condition of components and plants from the technical and business management point of view therefore becomes one of the fundamental questions and the key to efficient management and maintenance. A new way to determine the maintenance strategy can be called: Knowledge Based Maintenance. A simple method for determining strategies while taking the technical condition of the components of the production process into account to the greatest possible degree which can be shown. A software with an algorithm for Knowledge Based Maintenance leads the user during complex work to the determination of maintenance strategies for this complex plant components. (orig.)

  16. Evidence-based policy

    DEFF Research Database (Denmark)

    Vohnsen, Nina Holm

    2013-01-01

    A current ambition in welfare states as diverse as Denmark, the UK, and in the USA is to base political decision making on rigorous research (Cartwright et al 2009; Mulgan 2009; Bason 2010). Sound as this might seem the ambition has nevertheless been problematized by both policy-makers and the re......A current ambition in welfare states as diverse as Denmark, the UK, and in the USA is to base political decision making on rigorous research (Cartwright et al 2009; Mulgan 2009; Bason 2010). Sound as this might seem the ambition has nevertheless been problematized by both policy...... a full account, see Vohnsen 2011). These insights will be relevant for the anthropological researcher of legislative processes who wishes to move beyond a merely discursive approach to the study of policy and politics....

  17. Flow Based Algorithm

    Directory of Open Access Journals (Sweden)

    T. Karpagam

    2012-01-01

    Full Text Available Problem statement: Network topology design problems find application in several real life scenario. Approach: Most designs in the past either optimize for a single criterion like shortest or cost minimization or maximum flow. Results: This study discussed about solving a multi objective network topology design problem for a realistic traffic model specifically in the pipeline transportation. Here flow based algorithm focusing to transport liquid goods with maximum capacity with shortest distance, this algorithm developed with the sense of basic pert and critical path method. Conclusion/Recommendations: This flow based algorithm helps to give optimal result for transporting maximum capacity with minimum cost. It could be used in the juice factory, milk industry and its best alternate for the vehicle routing problem.

  18. Content Based Video Retrieval

    Directory of Open Access Journals (Sweden)

    B. V. Patel

    2012-10-01

    Full Text Available Content based video retrieval is an approach for facilitating the searching and browsing of large image collections over World Wide Web. In this approach, video analysis is conducted on low level visual properties extracted from video frame. We believed that in order to create an effective video retrieval system, visual perception must be taken into account. We conjectured that a technique which employs multiple features for indexing and retrieval would be more effective in the discrimination and search tasks of videos. In order to validate this claim, content based indexing and retrieval systems were implemented using color histogram, various texture features and other approaches. Videos were stored in Oracle 9i Database and a user study measured correctness of response.

  19. Dictionary Based Image Segmentation

    OpenAIRE

    Dahl, Anders Bjorholm; Dahl, Vedrana Andersen

    2015-01-01

    We propose a method for weakly supervised segmentationof natural images, which may contain both textured or non-texturedregions. Our texture representation is based on a dictionary of imagepatches. To divide an image into separated regions with similar texturewe use an implicit level sets representation of the curve, which makesour method topologically adaptive. In addition, we suggest a multi-labelversion of the method. Finally, we improve upon a similar texture representation,by formulating...

  20. Argument based machine learning

    OpenAIRE

    Možina, Martin

    2014-01-01

    The Thesis presents a novel approach to machine learning, called ABML (argument based machine learning). This approach combines machine learning from examples with some concepts from the field of defeasible argumentation, where arguments are used together with learning examples by learning methods in the induction of a hypothesis. An argument represents a relation between the class value of a particular learning example and its attributes and can be regarded as a partial explanation of this e...

  1. Plasmonics based VLSI processes

    Directory of Open Access Journals (Sweden)

    Shreya Bhattacharya

    2013-04-01

    Full Text Available In continuum to my previous paper titled‘Implementation of plasmonics in VLSI’, this paperattempts to explore further, the actual physicalrealization of an all-plasmonic chip. In this paper,various methods of plasmon-basedphotolithography have been discussed and anobservation is made w.r.t the cost effectiveness andease of adaptability. Also, plasmonics based activeelement has been discussed which would helpunravel further arenas ofapproaches and methodstowards the realization of an all-plasmonic chip.

  2. Graphene-based biosensors

    Science.gov (United States)

    Lebedev, A. A.; Davydov, V. Yu.; Novikov, S. N.; Litvin, D. P.; Makarov, Yu. N.; Klimovich, V. B.; Samoilovich, M. P.

    2016-07-01

    Results of developing and testing graphene-based sensors capable of detecting protein molecules are presented. The biosensor operation was checked using an immunochemical system comprising fluorescein dye and monoclonal antifluorescein antibodies. The sensor detects fluorescein concentration on a level of 1-10 ng/mL and bovine serum albumin-fluorescein conjugate on a level of 1-5 ng/mL. The proposed device has good prospects for use for early diagnostics of various diseases.

  3. Ferrocene base metal chelates

    International Nuclear Information System (INIS)

    Review of the works, devoted to different types of ferrocene metal chelates and to a possibility of ferrocene-containing ligand modification by means of complexing, is presented. Structure, properties and spectral characteristics of transitional metal, rare earth element, Cd2+, UO22+, Th4+ etc. complexes with ferrocene diketones, ferrocene acyl derivatives based on thiosemicarbazones and hydrazones and other heterometal ferrocene-containing metal chelates, are considered. 134 refs., 1 tab

  4. Polysiloxane based neutron detectors

    OpenAIRE

    Dalla Palma, Matteo

    2016-01-01

    In the last decade, neutron detection has been attracting the attention of the scientific community for different reasons. On one side, the increase in the price of 3He, employed in the most efficient and the most widely used neutron detectors. On the other side, the harmfulness of traditional xylene based liquid scintillators, used in extremely large volumes for the detection of fast neutrons. Finally, the demand for most compact and rough systems pushed by the increased popularity of neutro...

  5. Spiritual-based Leadership

    DEFF Research Database (Denmark)

    Pruzan, Peter

    2015-01-01

    Although far from mainstream, the concept of spiritual-based leadership is emerging as an inclusive and yet highly personal approach to leadership that integrates a leader’s inner perspectives on identity, purpose, responsibility and success with her or his decisions and actions in the outer world...... of business—and therefore it is also emerging as a significant framework for understanding, practicing, communicating and teaching the art and profession of leadership....

  6. Onlincolnshire Knowledge Base Collaboration

    OpenAIRE

    Fuller, Ted; Bosworth, Gary; Deville, Jane

    2016-01-01

    This report outlines the Onlincolnshire Knowledge Base Collaboration project undertaken by Lincoln Business School between May 2014 and September 2015. Onlincolnshire is a Lincolnshire County Council-run project which is part-funded by the East Midlands European Regional Development Fund (ERDF) Programme 2007 to 2013. As well as improving the broadband infrastructure, Onlincolnshire delivered a range of support to Lincolnshire’s Small and Medium Sized Enterprises (SMEs) through the “Business...

  7. Instance based function learning

    OpenAIRE

    Ramon, Jan; De Raedt, Luc

    1999-01-01

    The principles of instance based function learning are presented. In IBFL one is given a set of positive examples of a functional predicate. These examples are true ground facts that illustrate the input output behaviour of the predicate. The purpose is then to predict the output of the predicate given a new input. Further assumptions are that there is no background theory and that the inputs and outputs of the predicate consist of structured terms. IBFL is a novel technique that addresses th...

  8. Dictionary Based Image Segmentation

    DEFF Research Database (Denmark)

    Dahl, Anders Bjorholm; Dahl, Vedrana Andersen

    2015-01-01

    We propose a method for weakly supervised segmentation of natural images, which may contain both textured or non-textured regions. Our texture representation is based on a dictionary of image patches. To divide an image into separated regions with similar texture we use an implicit level sets...... in an efficient implementation of our segmentation method. We experimentally validated our approach on a number of natural as well as composed images....

  9. Refrigerator Based on Chemisorption

    Science.gov (United States)

    Jones, Jack A.

    1987-01-01

    Reversible chemical reaction generates pressurized oxygen for cooling. Concept for cryogenic refrigerator based on chemical absorption of oxygen by praseodymium/cerium oxide (PCO) compound. Refrigerator produces cryogenic liquid for cooling infrared sensors. Also used for liquefying air and separating oxygen from nitrogen in air. In chemisorption refrigerator, PCO alternately absorbs and desorbs oxygen depending on whether cooled or heated. One pair of compressors accepts oxygen while others releases it. Compressed oxygen liquefied when precooked and expanded.

  10. MEMS based reference oscillator

    OpenAIRE

    Hedestig, Joel

    2005-01-01

    The interest in tiny wireless applications raises the demand for an integrated reference oscillator with the same performance as the macroscopic quartz crystal reference oscillators. The main challenge of the thesis is to prove that it is possible to build a MEMS based oscillator that approaches the accuracy level of existing quartz crystal oscillators. The MEMS resonator samples which Philips provides are measured and an equivalent electrical model is designed for them. This model is used in...

  11. Evidence based pediatrics.

    OpenAIRE

    Elizabeta ZISOVSKA

    2015-01-01

    It is very difficult to define the entire phrase “Evidence based pediatrics”, covering all components of this overused sentence. The definition comes out of the common sentence and it means integration of the individual clinical expertize together with the best external clinically available evidence of the systematic reviews which are of interest and benefit of the individual patient.Development of clinically appropriate structured question follows PICO model, i.e. containing f...

  12. Lignocellulose-based bioproducts

    CERN Document Server

    Karimi, Keikhosro

    2015-01-01

    This volume provides the technical information required for the production of biofuels and chemicals from lignocellulosic biomass. It starts with a brief overview of the importance, applications, and production processes of different lignocellulosic products. Further chapters review the perspectives of waste-based biofuels and biochemicals; the pretreatment of lignocellulosic biomass for biofuel production; cellulolytic enzyme systems for the hydrolysis of lignocelluloses; and basic and applied aspects of the production of bioethanol, biogas, biohydrogen, and biobutanol from lignocelluloses.

  13. As bases do petismo

    Directory of Open Access Journals (Sweden)

    David Samuels

    2004-10-01

    Full Text Available A partir dos dados do ESEB de 2002 o autor realiza um estudo das bases eleitorais do PT e de hipóteses sobre a natureza do petismo. Através de técnicas estatísticas multivariadas, são testadas relações do petismo com variáveis demográficas, socioeconômicas e variáveis relativas a questões políticas específicas. Os resultados apontam que apenas a escolaridade tem uma associação específica com o petismo, com implicações para o seu comportamento sócio-político.Based on the results of the 2002 Brazilian Electoral Study, the author analyses the electoral bases of the Worker´s Party and the factors associated with the "petismo". The relationships between the "petismo"and the socioeconomic, demographic and political variables are tested using multivariate analysis. The results indicate that the only "social category"associated with "petismo"is level of education, and it has clear implications to their social and political behavior.

  14. Microbead agglutination based assays

    KAUST Repository

    Kodzius, Rimantas

    2013-01-21

    We report a simple and rapid room temperature assay for point-of-care (POC) testing that is based on specific agglutination. Agglutination tests are based on aggregation of microbeads in the presence of a specific analyte thus enabling the macroscopic observation. Such tests are most often used to explore antibody-antigen reactions. Agglutination has been used for protein assays using a biotin/streptavidin system as well as a hybridization based assay. The agglutination systems are prone to selftermination of the linking analyte, prone to active site saturation and loss of agglomeration at high analyte concentrations. We investigated the molecular target/ligand interaction, explaining the common agglutination problems related to analyte self-termination, linkage of the analyte to the same bead instead of different microbeads. We classified the agglutination process into three kinds of assays: a two- component assay, a three-component assay and a stepped three- component assay. Although we compared these three kinds of assays for recognizing DNA and protein molecules, the assay can be used for virtually any molecule, including ions and metabolites. In total, the optimized assay permits detecting analytes with high sensitivity in a short time, 5 min, at room temperature. Such a system is appropriate for POC testing.

  15. Molecule-based magnets

    Indian Academy of Sciences (India)

    J V Yakhmi

    2009-06-01

    The conventional magnetic materials used in current technology, such as, Fe, Fe2O3, Cr2O3, SmCo5, Nd2Fe14B etc are all atom-based, and their preparation/processing require high temperature routes. Employing self-assembly methods, it is possible to engineer a bulk molecular material with long-range magnetic order, mainly because one can play with the weak intermolecular interactions. Since the first successful synthesis of molecular magnets in 1986, a large variety of them have been synthesized, which can be categorized on the basis of the chemical nature of the magnetic units involved: organic-, metal-based systems, heterobimetallic assemblies, or mixed organic–inorganic systems. The design of molecule-based magnets has also been extended to the design of poly-functional molecular magnets, such as those exhibiting second-order optical nonlinearity, liquid crystallinity, or chirality simultaneously with long-range magnetic order. Solubility, low density and biocompatibility are attractive features of molecular magnets. Being weakly coloured, unlike their opaque classical magnet ‘cousins’ listed above, possibilities of photomagnetic switching exist. Persistent efforts also continue to design the ever-elusive polymer magnets towards applications in industry. While providing a brief overview of the field of molecular magnetism, this article highlights some recent developments in it, with emphasis on a few studies from the author’s own lab.

  16. Lunar base initiative 1992

    Science.gov (United States)

    Koelle, H. H.

    The return to the Moon is no longer a question of yes or no, but a question of when and how. The first landing of a human being on the lunar surface in 1969 was a purely national effort of the U.S.A. Building a lunar base and operating it in the next century is rather a task for all nations of this planet, even if one nation could do it alone. However, there are several alternatives to carry out such a program and these will and should be debated during the next years on an urgent basis. To do this, one has to take into account not only the historical accomplishments and the present trends of cooperation in space programs, but also recent geopolitical developments as well as the frame of reference established by international law. The case for an International Lunar Base (ILB) has been presented to the International Academy of Astronautics on 11 October 1987 by the IAA Ad Hoc Committee "Return-to-the-Moon". This draft of a position paper was subsequently published in Acta Astronautica Vol. 17, No. 5, (pp. 463-489) with the request of public debate particularly by the members of the Academy. Some 80 Academicians responded to this invitation by the President of the Academy and voiced their opinions on the questions and issues raised by this draft of a position paper. This led to a refinement of the arguments and assumptions made and it is now possible to prepare an improved position paper proposing concrete steps which may lead to an ILB. An issue of this proportion must start with a discussion of goals and objectives to be arranged in some kind of a ranked order. It also has to take note of the limitations existing at any time by the availability of suitable space transportation systems. These will determine the acquisition date and rate of growth of a lunar base. The logistics system will also greatly influence the base characteristics and layout. The availability of heavy lift launch vehicles would simplify the task and allow to concentrate the construction

  17. Advances in thin-film solar cells

    CERN Document Server

    Dharmadasa, I M

    2012-01-01

    This book concentrates on the latest developments in our understanding of solid-state device physics. The material presented is mainly experimental and based on CdTe thin-film solar cells. It extends these new findings to CIGS thin-film solar cells and presents a new device design based on graded bandgap multilayer solar cells. This design has been experimentally tested using the well-researched GaAs/AlGaAs system and initial devices have shown impressive device parameters. These devices are capable of absorbing all radiation (UV, visible, and infra-red) within the solar spectrum and combines

  18. Polyolefin-Based Aerogels

    Science.gov (United States)

    Lee, Je Kyun; Gould, George

    2012-01-01

    An organic polybutadiene (PB) rubberbased aerogel insulation material was developed that will provide superior thermal insulation and inherent radiation protection, exhibiting the flexibility, resiliency, toughness, and durability typical of the parent polymer, yet with the low density and superior insulation properties associated with the aerogels. The rubbery behaviors of the PB rubber-based aerogels are able to overcome the weak and brittle nature of conventional inorganic and organic aerogel insulation materials. Additionally, with higher content of hydrogen in their structure, the PB rubber aerogels will also provide inherently better radiation protection than those of inorganic and carbon aerogels. Since PB rubber aerogels also exhibit good hydrophobicity due to their hydrocarbon molecular structure, they will provide better performance reliability and durability as well as simpler, more economic, and environmentally friendly production over the conventional silica or other inorganic-based aerogels, which require chemical treatment to make them hydrophobic. Inorganic aerogels such as silica aerogels demonstrate many unusual and useful properties. There are several strategies to overcoming the drawbacks associated with the weakness and brittleness of silica aerogels. Development of the flexible fiber-reinforced silica aerogel composite blanket has proven one promising approach, providing a conveniently fielded form factor that is relatively robust toward handling in industrial environments compared to silica aerogel monoliths. However, the flexible silica aerogel composites still have a brittle, dusty character that may be undesirable, or even intolerable, in certain applications. Although the cross-linked organic aerogels such as resorcinol-formaldehyde (RF), polyisocyanurate, and cellulose aerogels show very high impact strength, they are also very brittle with little elongation (i.e., less rubbery). Also, silica and carbon aerogels are less efficient

  19. Microstructure characterization of the soda-lime-glass/copper-indium-gallium-selenium interface in Cu-poor Cu(In,Ga)Se2 thin films

    International Nuclear Information System (INIS)

    The microstructure characteristics of the soda-lime-glass/Cu(In,Ga)Se2 (SLG/CIGS) interface in Cu-poor CIGS films are investigated by transmission electron microscopy and selected area electronic diffraction (SAED). The SAED patterns show very sharp and strong spots, indicating the main structure of CIGS chalcopyrite. Small dispersed crystals with size distribution from 2 to 5 nm seem to be embedded in amorphous matrix, and additional spots indicate the presence of an ordered vacancy compound (OVC). This observation is consistent with the Raman results, and the OVC phase with the nanoclusters exists in the CIGS matrix, instead of layer structure. Lattice distortion results in local changes in contrast. Some pseudo-disordered structure is observed, however, the structure is actually the chalcopyrite CIGS structure. 180° rotation twins are also observed at the SLG/CIGS interface. Lattice distortion is widely observed at the interface of the Cu-poor CIGS films, and the extra spots could be caused by different lattice orientations. - Highlights: • Cu(In,Ga)Se2 (CIGS) were prepared on bare soda-lime-glass (SLG) substrates. • Microstructure of the SLG/CIGS interface was investigated. • An ordered vacancy compound (OVC) phase was observed. • The OVC phase with nanoclusters exists in the CIGS matrix, instead of layer structure. • 180° rotation twins were observed at the SLG/CIGS interface

  20. Microstructure characterization of the soda-lime-glass/copper-indium-gallium-selenium interface in Cu-poor Cu(In,Ga)Se{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jian, E-mail: wangjustb@gmail.com; Qiao, Yi; Zhu, Jie, E-mail: jiezhu@ustb.edu.cn

    2015-05-29

    The microstructure characteristics of the soda-lime-glass/Cu(In,Ga)Se{sub 2} (SLG/CIGS) interface in Cu-poor CIGS films are investigated by transmission electron microscopy and selected area electronic diffraction (SAED). The SAED patterns show very sharp and strong spots, indicating the main structure of CIGS chalcopyrite. Small dispersed crystals with size distribution from 2 to 5 nm seem to be embedded in amorphous matrix, and additional spots indicate the presence of an ordered vacancy compound (OVC). This observation is consistent with the Raman results, and the OVC phase with the nanoclusters exists in the CIGS matrix, instead of layer structure. Lattice distortion results in local changes in contrast. Some pseudo-disordered structure is observed, however, the structure is actually the chalcopyrite CIGS structure. 180° rotation twins are also observed at the SLG/CIGS interface. Lattice distortion is widely observed at the interface of the Cu-poor CIGS films, and the extra spots could be caused by different lattice orientations. - Highlights: • Cu(In,Ga)Se{sub 2} (CIGS) were prepared on bare soda-lime-glass (SLG) substrates. • Microstructure of the SLG/CIGS interface was investigated. • An ordered vacancy compound (OVC) phase was observed. • The OVC phase with nanoclusters exists in the CIGS matrix, instead of layer structure. • 180° rotation twins were observed at the SLG/CIGS interface.

  1. Characteristics Data Base

    International Nuclear Information System (INIS)

    The LWR Serial Numbers Database System (SNDB) contains detailed data about individual, historically discharged LWR spent fuel assemblies. This data includes the reactor where used, the year the assemblies were discharged, the pool where they are currently stored, assembly type, burnup, weight, enrichment, and an estimate of their radiological properties. This information is distributed on floppy disks to users in the nuclear industry to assist in planning for the permanent nuclear waste repository. This document describes the design and development of the SNDB. It provides a complete description of the file structures and an outline of the major code modules. It serves as a reference for a programmer maintaining the system, or for others interested in the technical detail of this database. This is the initial version of the SNDB. It contains historical data through December 31, 1987, obtained from the Energy Information Administration (EIA). EIA obtains the data from the utility companies via the RW-859 Survey Form. It evaluates and standardizes the data and distributes the resulting batch level database as a large file on magnetic tape. The Characteristics Data Base obtains this database for use in the LWR Quantities Data Base. Additionally, the CDB obtains the individual assembly level detail from EIA for use in the SNDB. While the Quantities Data Base retains only the level of detail necessary for its reporting, the SNDB does retain and use the batch level data to assist in the identification of a particular assembly serial number. We expect to update the SNDB on an annual basis, as new historical data becomes available

  2. Agent-Based Optimization

    CERN Document Server

    Jędrzejowicz, Piotr; Kacprzyk, Janusz

    2013-01-01

    This volume presents a collection of original research works by leading specialists focusing on novel and promising approaches in which the multi-agent system paradigm is used to support, enhance or replace traditional approaches to solving difficult optimization problems. The editors have invited several well-known specialists to present their solutions, tools, and models falling under the common denominator of the agent-based optimization. The book consists of eight chapters covering examples of application of the multi-agent paradigm and respective customized tools to solve  difficult optimization problems arising in different areas such as machine learning, scheduling, transportation and, more generally, distributed and cooperative problem solving.

  3. Speckle-based wavemeter

    DEFF Research Database (Denmark)

    Hanson, Steen Grüner; Jakobsen, Michael Linde; Chakrabarti, Maumita

    2015-01-01

    A spectrometer based on the application of dynamic speckles will be disclosed. The method relies on scattering of primarily coherent radiation from a slanted rough surface. The scattered radiation is collected on a detector array and the speckle displacement is monitored during a change in the...... incident wavelength. The change of wavelength gives an almost linear phaseshift across the scattering surface resulting in an almost linear shift of the speckle pattern, which is subsequently monitored. It is argued that frequency changes close to 100 MHz can be probed using a common CMOS array...

  4. Commonality based interoperability

    Science.gov (United States)

    Moulton, Christine L.; Hepp, Jared J.; Harrell, John

    2016-05-01

    What interoperability is and why the Army wants it between systems is easily understood. Enabling multiple systems to work together and share data across boundaries in a co-operative manner will benefit the warfighter by allowing for easy access to previously hard-to-reach capabilities. How to achieve interoperability is not as easy to understand due to the numerous different approaches that accomplish the goal. Commonality Based Interoperability (CBI) helps establish how to achieve the goal by extending the existing interoperability definition. CBI is not an implementation, nor is it an architecture; it is a definition of interoperability with a foundation of establishing commonality between systems.

  5. Cellular based cancer vaccines

    DEFF Research Database (Denmark)

    Hansen, Morten; Met, O; Svane, I M;

    2012-01-01

    Cancer vaccines designed to re-calibrate the existing host-tumour interaction, tipping the balance from tumor acceptance towards tumor control holds huge potential to complement traditional cancer therapies. In general, limited success has been achieved with vaccines composed of tumor...... in vitro migration via autocrine receptor-mediated endocytosis of CCR7. In the current review, we discuss optimal design of DC maturation focused on pre-clinical as well as clinical results from standard and polarized dendritic cell based cancer vaccines....

  6. Refractive index based measurements

    DEFF Research Database (Denmark)

    2014-01-01

    In a method for performing a refractive index based measurement of a property of a fluid such as chemical composition or temperature by observing an apparent angular shift in an interference fringe pattern produced by back or forward scattering interferometry, ambiguities in the measurement caused...... by the apparent shift being consistent with one of a number of numerical possibilities for the real shift which differ by 2n are resolved by combining measurements performed on the same sample using light paths therethrough of differing lengths....

  7. COMPUTER BASED ENVIRONMENT CONTROLS

    OpenAIRE

    Macoveiciuc Pastorel

    2011-01-01

    The aim of these notes is to give an overview of the main activities of computer based activities controls. The basic principles of computer controls should be common to all sectors and to most types of hardware and software. The absence of a common definition of computer control may, in part, be due to the relative newness of computer controls. A key feature of many organisations today is change. Although not necessarily the driver of change, IT is invariably an intrinsec component and much ...

  8. WAP - based telemedicine applications

    International Nuclear Information System (INIS)

    Telemedicine refers to the utilization of telecommunication technology for medical diagnosis, treatment, and patient care. Its aim is to provide expert-based health care to remote sites through telecommunication and information technologies. The significant advances in technologies have enabled the introduction of a broad range of telemedicine applications, which are supported by computer networks, wireless communication, and information superhighway. For example, some hospitals are using tele-radiology for remote consultation. Such a system includes medical imaging devices networked with computers and databases. Another growing area is patient monitoring, in which sensors are used to acquire biomedical signals, such as electrocardiogram (ECG), blood pressure, and body temperature, from a remote patient, who could be in bed or moving freely. The signals are then relayed to remote systems for viewing and analysis. Telemedicine can be divided into two basic modes of operations: real-time mode, in which the patient data can be accessed remotely in real-time, and store-and-forward mode, in which the acquired data does not have to be accessed immediately. In the recent years, many parties have demonstrated various telemedicine applications based on the Internet and cellular phone as these two fields have been developing rapidly. A current, recognizable trend in telecommunication is the convergence of wireless communication and computer network technologies. This has been reflected in recently developed telemedicine systems. For example, in 1998 J. Reponen, et al. have demonstrated transmission and display of computerized tomography (CT) examinations using a remote portable computer wirelessly connected to a computer network through TCP/IP on a GSM cellular phone. Two years later, they carried out the same tests with a GSM-based wireless personal digital assistant (PDA). The WAP (Wireless Application Protocol) Forum was founded in 1997 to create a global protocol

  9. Wood-Based Bioenergy

    OpenAIRE

    Hoel, Michael; Sletten, Thea Marcelia

    2014-01-01

    During recent years increased attention has been given to second-generation wood-based bioenergy. The carbon stored in the forest is highest when there is little or no harvest from the forest. Increasing the harvest from a forest, in order to produce more bioenergy, may thus conflict with the direct benefit of the forest as a carbon sink. We analyze this conflict using a simple model where bioenergy and fossil energy are perfect substitutes. Our analysis shows how the social optimum will depe...

  10. LIGHTWEIGHT CONCRETE BASED GRANSHLAK

    Directory of Open Access Journals (Sweden)

    NETESA M. I.

    2016-02-01

    Full Text Available Raising of problem. Concrete advisable to obtain a low strength with local secondary resources for recycling and reduce the environmental burden on the environment. But it is important to design such concrete compositions with a reduced flow of cement. It is known that the coefficient of efficiency of use of cement in the concrete of the heavy and B10 is less than about 0.5, which is almost two times smaller than in class B15 concrete and above. Even lower coefficient of efficiency in light concrete cement low strength. Therefore, it is important to find patterns determining the composition of lightweight concrete based on local-products industry with more efficient use of cement in them. Purpose.. Based on the analysis of earlier research results, including with the use of methods of mathematical planning of experiments to determine the concrete contents, which can provide the requirements for the underlying layers of the floor, the compressive strength of which should correspond to the class B5. It is important to provide the required strength at minimum flow of the cement, which is the most expensive and energy-intensive part of concrete. Conclusion. Analysis of the test results of control samples of concrete in 28-day-old, the following laws. The required tensile strength of concrete compressive strength of 7.0 MPa can be obtained in the test range when used in formulations as a filler as the Dnieper hydroelectric power station fly ash and tailings Krivoy Rog iron ore YuGOK. To ensure providing the required characteristic strength of the concrete in the underlying layers of the floor is advisable to use a nominal composition per cubic meter of concrete: cement 160 kg granshlaka Plant named after Petrovsky, 675 kg of fly ash Dnieper HPP 390 kg, 400 kg of sand, 230 liters of water. Thus, while ensuring rational grain composition components can obtain the desired strength lightweight concrete based granshlaka plant Petrovsky, using as fillers

  11. RF Based Spy

    OpenAIRE

    Robot Prerna Jain; Pallavi N. Firke

    2014-01-01

    The intention of this paper is to reduce human victims in terrorist attack such as 26/11. So this problem can be overcome by designing the RF based spy robot which involves wireless camera. so that from this we can examine rivals when it required. This robot can quietly enter into enemy area and sends us the information via wireless camera. On the other hand one more feature is added in this robot that is colour sensor. Colour sensor senses the colour of surface and according ...

  12. Teradata data base computer

    Energy Technology Data Exchange (ETDEWEB)

    1984-04-01

    To meet the growing demand for information management of large databases, Teradata Corporation has introduced the DBC/1012 data base computer, an IBM plug-compatible system that can handle data volumes up to a trillion bytes. Teradata estimates the DBC/1012 to be one-third the cost of an all-software relational system on a general purpose mainframe. Cost effectiveness, as well as fault tolerance, is achieved by a parallel architecture which processes data asynchronously using multiple independent microprocessors. Another cost saving results from the resources on the host mainframe that become available once the mainframe is relieved of the burden of maintaining the database.

  13. Sustainability Base Construction Update

    Science.gov (United States)

    Mewhinney, Michael

    2012-01-01

    Construction of the new Sustainability Base Collaborative support facility, expected to become the highest performing building in the federal government continues at NASA's Ames Research Center, Moffet Field, Calif. The new building is designed to achieve a platinum rating under the leadership in Energy and Environment Design (LEED) new construction standards for environmentally sustainable construction developed by the U. S. Green Building Council, Washington, D. C. When completed by the end of 2011, the $20.6 million building will feature near zero net energy consumption, use 90 percent less potable water than conventionally build buildings of equivalent size, and will result in reduced building maintenance costs.

  14. Bi-based superconductor

    Directory of Open Access Journals (Sweden)

    S E Mousavi

    2009-08-01

    Full Text Available   In this paper, Bi-Sr-Ca-Cu-O (BCSCCO system superconductor is made by the solid state reaction method. The effect of doping Pb, Cd, Sb, Cu and annealing time on the critical temperature and critical current density have been investigated. The microstructure and morphology of the samples have been studied by X-ray diffraction, scanning electron microscope and energy dispersive X-ray. The results show that the fraction of Bi-2223 phase in the Bi- based superconductor, critical temperature and critical current density depend on the annealing temperature, annealing time and the kind and amount of doping .

  15. Knowledge based Entrepreneurship

    DEFF Research Database (Denmark)

    Heebøll, John

    This book is dedicated enterprising people with a technical or a scientific background who consider commercializing ideas and inventions within their field of expertise via a new business activity or a new company. It aims at distilling experiences from many successful and not so successful start......-up ventures from the Technical University of Denmark, 1988 – 2008 into practical, portable knowledge that can be used by future knowledge-based entrepreneurs to set up new companies efficiently or to stay away from it; to do what’s needed and avoid the pitfalls....

  16. Vision-based interaction

    CERN Document Server

    Turk, Matthew

    2013-01-01

    In its early years, the field of computer vision was largely motivated by researchers seeking computational models of biological vision and solutions to practical problems in manufacturing, defense, and medicine. For the past two decades or so, there has been an increasing interest in computer vision as an input modality in the context of human-computer interaction. Such vision-based interaction can endow interactive systems with visual capabilities similar to those important to human-human interaction, in order to perceive non-verbal cues and incorporate this information in applications such

  17. Pitch Based Sound Classification

    OpenAIRE

    Nielsen, Andreas Brinch; Hansen, Lars Kai; Kjems, U.

    2006-01-01

    A sound classification model is presented that can classify signals into music, noise and speech. The model extracts the pitch of the signal using the harmonic product spectrum. Based on the pitch estimate and a pitch error measure, features are created and used in a probabilistic model with soft-max output function. Both linear and quadratic inputs are used. The model is trained on 2 hours of sound and tested on publicly available data. A test classification error below 0.05 with 1 s classif...

  18. Cu(In,Ga)Se{sub 2} solar cells with superstrate structure using lift-off process

    Energy Technology Data Exchange (ETDEWEB)

    Osada, Shintaro; Anegawa, Takaya; Takakura, Hideyuki [College of Science and Engineering, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu 525-8577 (Japan); Abe, Yasuhiro; Minemoto, Takashi [Ritsumeikan Global Innovation Research Organization, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu 525-8577 (Japan)

    2011-01-15

    Cu(In,Ga)Se{sub 2} (CIGS) solar cells with a superstrate structure were fabricated using a lift-off process. To widen the variety of substrate choices for CIGS solar cells, a lift-off process was developed without an intentional sacrificial layer between the CIGS and Mo back-contact layers. The CIGS solar cells fabricated on Mo/soda-lime glass (SLG) were transferred to an alternative SLG substrate. The conversion efficiency of the CIGS solar cells with the superstrate structure was 5.1%, which was almost half that of the CIGS solar cells with a substrate structure prior to the lift-off process. The low conversion efficiency was caused by the high series resistance and low shunt resistance, which would be due to the junction resistance between the CIGS/back contact and cracks introduced during the lift-off process, respectively. (author)

  19. Peeled-off flexible Cu(In,Ga)Se2 solar cells and Na diffusion effects on cell performances

    Science.gov (United States)

    Sadono, Adiyudha; Ogihara, Tomohiro; Hino, Masashi; Yamamoto, Kenji; Yamada, Akira

    2016-07-01

    Na diffusion on Cu(In,Ga)Se2 (CIGS) solar cells fabricated on top of polyimide-coated soda-lime glass (SLG) substrate were investigated. Polyimide-coated SLG that can be used as substrate for fabricating flexible solar cells by peeled-off process, shown to have the same efficiency with SLG reference which is around 12%, indicating diffusion of almost same amount of Na from the substrates into the CIGS. Additional Na incorporation by NaF post-deposition treatment (PDT) were applied to CIGS deposited on substrates with different Na quantity to understand the Na diffusion effect prior and post CIGS deposition. Improvement of cells performance were observed for CIGS deposited on both substrates with or without Na diffusion. Final conversion efficiency of 15% was achieved after PDT for CIGS deposited on Na-contained substrates suggesting that PDT can be used even for CIGS with Na diffusion from the substrate. [Figure not available: see fulltext.

  20. Moon base reactor system

    Science.gov (United States)

    Chavez, H.; Flores, J.; Nguyen, M.; Carsen, K.

    1989-01-01

    The objective of our reactor design is to supply a lunar-based research facility with 20 MW(e). The fundamental layout of this lunar-based system includes the reactor, power conversion devices, and a radiator. The additional aim of this reactor is a longevity of 12 to 15 years. The reactor is a liquid metal fast breeder that has a breeding ratio very close to 1.0. The geometry of the core is cylindrical. The metallic fuel rods are of beryllium oxide enriched with varying degrees of uranium, with a beryllium core reflector. The liquid metal coolant chosen was natural lithium. After the liquid metal coolant leaves the reactor, it goes directly into the power conversion devices. The power conversion devices are Stirling engines. The heated coolant acts as a hot reservoir to the device. It then enters the radiator to be cooled and reenters the Stirling engine acting as a cold reservoir. The engines' operating fluid is helium, a highly conductive gas. These Stirling engines are hermetically sealed. Although natural lithium produces a lower breeding ratio, it does have a larger temperature range than sodium. It is also corrosive to steel. This is why the container material must be carefully chosen. One option is to use an expensive alloy of cerbium and zirconium. The radiator must be made of a highly conductive material whose melting point temperature is not exceeded in the reactor and whose structural strength can withstand meteor showers.

  1. Design Based Wilderness Education

    Directory of Open Access Journals (Sweden)

    Christopher R. Saulnier

    2015-02-01

    Full Text Available The Massachusetts Institute of Technology (MIT has been collaborating since 2010 with the Singapore Ministry of Education to help develop the Singapore University of Technology and Design (SUTD. One element of this collaboration, the Global Leadership Program (GLP, aims to provide SUTD students with the opportunity to interact with the MIT community and experience MIT’s academic culture. During GLP students participate in a program designed to develop leadership ability while also increasing their understanding of engineering science and design thinking. This paper introduces a curriculum combining the pedagogies of design-based learning and wilderness education that was implemented in the summer of 2014 to holistically address the development of these three competencies. Through design-based learning activities, both for and in a natural environment, students were encouraged to develop competencies in engineering science and engineering design while exploring the diverse attributes essential for success as an engineer. This paper examines the results of a retrospective post-then-pre survey administered to the participants upon completion of the program to explore the effects of the program on the development of professional engineering competencies. We find a statistically significant increase in items associated with Individual Leadership Skill, Group Leadership Skill and the role of Society and the Economy. These results are triangulated with student exit interviews and instructor observations.

  2. Model Based Definition

    Science.gov (United States)

    Rowe, Sidney E.

    2010-01-01

    In September 2007, the Engineering Directorate at the Marshall Space Flight Center (MSFC) created the Design System Focus Team (DSFT). MSFC was responsible for the in-house design and development of the Ares 1 Upper Stage and the Engineering Directorate was preparing to deploy a new electronic Configuration Management and Data Management System with the Design Data Management System (DDMS) based upon a Commercial Off The Shelf (COTS) Product Data Management (PDM) System. The DSFT was to establish standardized CAD practices and a new data life cycle for design data. Of special interest here, the design teams were to implement Model Based Definition (MBD) in support of the Upper Stage manufacturing contract. It is noted that this MBD does use partially dimensioned drawings for auxiliary information to the model. The design data lifecycle implemented several new release states to be used prior to formal release that allowed the models to move through a flow of progressive maturity. The DSFT identified some 17 Lessons Learned as outcomes of the standards development, pathfinder deployments and initial application to the Upper Stage design completion. Some of the high value examples are reviewed.

  3. Microlaser-based displays

    Science.gov (United States)

    Bergstedt, Robert; Fink, Charles G.; Flint, Graham W.; Hargis, David E.; Peppler, Philipp W.

    1997-07-01

    Laser Power Corporation has developed a new type of projection display, based upon microlaser technology and a novel scan architecture, which provides the foundation for bright, extremely high resolution images. A review of projection technologies is presented along with the limitations of each and the difficulties they experience in trying to generate high resolution imagery. The design of the microlaser based projector is discussed along with the advantage of this technology. High power red, green, and blue microlasers have been designed and developed specifically for use in projection displays. These sources, in combination with high resolution, high contrast modulator, produce a 24 bit color gamut, capable of supporting the full range of real world colors. The new scan architecture, which reduces the modulation rate and scan speeds required, is described. This scan architecture, along with the inherent brightness of the laser provides the fundamentals necessary to produce a 5120 by 4096 resolution display. The brightness and color uniformity of the display is excellent, allowing for tiling of the displays with far fewer artifacts than those in a traditionally tiled display. Applications for the display include simulators, command and control centers, and electronic cinema.

  4. Constraint-based reachability

    Directory of Open Access Journals (Sweden)

    Arnaud Gotlieb

    2013-02-01

    Full Text Available Iterative imperative programs can be considered as infinite-state systems computing over possibly unbounded domains. Studying reachability in these systems is challenging as it requires to deal with an infinite number of states with standard backward or forward exploration strategies. An approach that we call Constraint-based reachability, is proposed to address reachability problems by exploring program states using a constraint model of the whole program. The keypoint of the approach is to interpret imperative constructions such as conditionals, loops, array and memory manipulations with the fundamental notion of constraint over a computational domain. By combining constraint filtering and abstraction techniques, Constraint-based reachability is able to solve reachability problems which are usually outside the scope of backward or forward exploration strategies. This paper proposes an interpretation of classical filtering consistencies used in Constraint Programming as abstract domain computations, and shows how this approach can be used to produce a constraint solver that efficiently generates solutions for reachability problems that are unsolvable by other approaches.

  5. Challenge Based Innovation gala

    CERN Document Server

    CERN. Geneva; Utriainen, Tuuli Maria; Toivonen, Harri; Nordberg, Markus

    2014-01-01

    Challenge Based Innovation gala   There’s a new experiment starting in CERN called IdeaLab where we work together with detector R&D researchers to help them to bridge their knowledge into a more human, societally oriented context. Currently we are located in B153, but will move our activities to a new facility next to the Globe in May 2014. One of our first pilot projects is a 5 month course CBI (Challenge Based Innovation) where two multidisciplinary student teams join forces with Edusafe & TALENT projects at CERN. Their goal is to discover what kind of tools for learning could be created in collaboration with the two groups. After months of user interviews and low resolution prototyping they are ready to share the results with us in the form of an afternoon gala. We warmly welcome you to join us to see the students' results and experience the prototypes they have conceived. The event is in three parts, you are welcome to visit all of them,...

  6. Knowledge Based Economy Assessment

    Directory of Open Access Journals (Sweden)

    Madalina Cristina Tocan

    2012-12-01

    Full Text Available The importance of knowledge-based economy (KBE in the XXI century isevident. In the article the reflection of knowledge on economy is analyzed. The main point is targeted to the analysis of characteristics of knowledge expression in economy and to the construction of structure of KBE expression. This allows understanding the mechanism of functioning of knowledge economy. Theauthors highlight the possibility to assess the penetration level of KBE which could manifest itself trough the existence of products of knowledge expression which could be created in acquisition, creation, usage and development of them. The latter phenomenon is interpreted as knowledge expression characteristics: economic and social context, human resources, ICT, innovative business and innovation policy. The reason for this analysis was based on the idea that in spite of the knowledge economy existence in all developed World countries adefinitive, universal list of indicators for mapping and measuring the KBE does not yet exists. Knowledge Expression Assessment Models are presented in the article.

  7. BIOMETRICS BASED USER AUTHENTICATION

    Directory of Open Access Journals (Sweden)

    Tanuj Tiwari

    2015-10-01

    Full Text Available Biometrics is automated methods of recognizing a person based on a physiological or behavioral characteristic. Biometrics technologies are base for a plethora of highly secure identification and personal verification solutions. It is measurement of biological characteristics – either physiological or behavioral – that verify the claimed identity of an individual. Physiological biometrics include fingerprints, iris recognition. voice verification, retina recognition, palm vein patterns, finger vein patterns, hand geometry and DNA But there arises a need for more robust systems in order to tackle the increasing incidents of security breaches and frauds. So there is always a need for fool proof technology that can provide security and safety to individuals and the transactions that the individuals make. Biometrics is increasingly used by organizations to verify identities, but coupled with quantum cryptography it offers a new range of security benefits with quantum cryptography where we form a key when we need it and then destroy it. In this paper, we give a brief overview of the field of biometrics and summarize some of its advantages, disadvantages, strengths, limitations, and related privacy concerns.

  8. LEU{sub b}ased Fission Mo-99 Process with Reduced Solid Wastes

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seungkon; Lee, Suseung; Jung, Sunghee; Hong, Soonbog; Jang, Kyungduk; Choi, Sang Mu; Lee, Jun Sig; Lim, Incheol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    {sup 99m} Tc emits 140 keV of very low gamma-ray radiation energy, as low as conventional diagnostic X-ray, and has short half-life of 6.0058 hours. Therefore, as radioactive tracer, {sup 99m} Tc provides high quality diagnostic images but keeps total patient radiation exposure low. Depending on the tagging pharmaceuticals and procedures, {sup 99m} Tc can be applied for the diagnostics of various target organs and diseases: brain, myocardium, thyroid, lungs, liver, gallbladder, kidneys, skeleton, blood and tumors. More than 95% of {sup 99}Mo is produced through fission of {sup 235}U worldwide because, {sup 99m}o generated from the fission (fission {sup 99}Mo) exhibits very high specific activity (<100 Ci/g). Over 90% of fission {sup 99}Mo producers have been used highly enriched uranium (HEU) targets so far. However, the IAEA recommends the use of low enriched uranium (LEU) to the {sup 99}Mo producers for nonproliferation reason. These days, worldwide {sup 99}Mo supply is not only insufficient but also unstable. Because, most of the main {sup 99}Mo production reactors are about 50 years old and suffered from frequent and unscheduled shutdown. Planned weekly productivity of 2000 Ci fission {sup 99}Mo, in a 6-day reference, will cover 100% domestic demand of Korea, as well as 20% of international market. It is expected to replace 4.3 million USD ($800/Ci) of {sup 99}Mo import for domestic market while exporting 82.8 million USD for world market, annually.

  9. MS Based Metabonomics

    Energy Technology Data Exchange (ETDEWEB)

    Want, Elizabeth J.; Metz, Thomas O.

    2010-03-01

    Metabonomics is the latest and least mature of the systems biology triad, which also includes genomics and proteomics, and has its origins in the early orthomolecular medicine work pioneered by Linus Pauling and Arthur Robinson. It was defined by Nicholson and colleagues in 1999 as the quantitative measurement of perturbations in the metabolite complement of an integrated biological system in response to internal or external stimuli, and is often used today to describe many non-global types of metabolite analyses. Applications of metabonomics are extensive and include toxicology, nutrition, pharmaceutical research and development, physiological monitoring and disease diagnosis. For example, blood samples from millions of neonates are tested routinely by mass spectrometry (MS) as a diagnostic tool for inborn errors of metabolism. The metabonome encompasses a wide range of structurally diverse metabolites; therefore, no single analytical platform will be sufficient. Specialized sample preparation and detection techniques are required, and advances in NMR and MS technologies have led to enhanced metabonome coverage, which in turn demands improved data analysis approaches. The role of MS in metabonomics is still evolving as instrumentation and software becomes more sophisticated and as researchers realize the strengths and limitations of current technology. MS offers a wide dynamic range, high sensitivity, and reproducible, quantitative analysis. These attributes are essential for addressing the challenges of metabonomics, as the range of metabolite concentrations easily exceeds nine orders of magnitude in biofluids, and the diversity of molecular species ranges from simple amino and organic acids to lipids and complex carbohydrates. Additional challenges arise in generating a comprehensive metabolite profile, downstream data processing and analysis, and structural characterization of important metabolites. A typical workflow of MS-based metabonomics is shown in Figure

  10. Mucin-Based Vaccines

    Science.gov (United States)

    Richardson, Jonathan P.; MacMillan, Derek

    Mucins are heavily O-glycosylated cell surface and secreted glycoproteins . In addition to orchestrating cell-extracellular matrix and cell-cell interactions in healthy organisms mucins are also the major carriers of altered glycosylation in carcinomas. Tumor-associated antigens displayed by cancer cells comprise oligosaccharide and glycopeptide motifs not encountered in the same locale or at the same frequency in healthy cells, and potentially confer a selective advantage to the tumor. Frequently tumor-associated antigens are under-glycosylated and prematurely sialylated, and it is these relatively simple saccharide and glycopeptide structures that have been targeted to serve as drug candidates in most cases. A major goal is to assemble glycopeptide vaccine candidates based on partial mucin sequences and displaying tumor-associated antigens that can mount a potent immunological tumor-specific response when, in reality, the tumor has already coerced the immune system into a state of co-existence.

  11. Pitch Based Sound Classification

    DEFF Research Database (Denmark)

    Nielsen, Andreas Brinch; Hansen, Lars Kai; Kjems, U

    2006-01-01

    A sound classification model is presented that can classify signals into music, noise and speech. The model extracts the pitch of the signal using the harmonic product spectrum. Based on the pitch estimate and a pitch error measure, features are created and used in a probabilistic model with soft......-max output function. Both linear and quadratic inputs are used. The model is trained on 2 hours of sound and tested on publicly available data. A test classification error below 0.05 with 1 s classification windows is achieved. Further more it is shown that linear input performs as well as a quadratic......, and that even though classification gets marginally better, not much is achieved by increasing the window size beyond 1 s....

  12. Fiber based optofluidic biosensors

    Science.gov (United States)

    Lismont, M.; Vandewalle, N.; Joris, B.; Dreesen, L.

    2014-09-01

    Medicinal diagnosis requires the development of innovative devices allowing the detection of small amounts of biological species. Among the large variety of available biosensors, the ones based on fluorescence phenomenon are really promising. Here, we show a prototype of the basic unit of a multi-sensing biosensor combining optics and microfluidics benefits. This unit makes use of two crossed optical fibers: the first fiber is used to carry small probe molecules droplets and excite fluorescence, while the second one is devoted to target molecules droplets transport and fluorescence detection. Within this scheme, the interaction takes place in each fiber node. The main benefits of this detection setup are the absence of fibers functionalization, the use of microliter volumes of target and probe species, their separation before interaction, and a better detection limit compared to cuvettes setups.

  13. Diffusion Based Photon Mapping

    DEFF Research Database (Denmark)

    Schjøth, Lars; Sporring, Jon; Fogh Olsen, Ole

    2008-01-01

    . To address this problem, we introduce a photon mapping algorithm based on nonlinear anisotropic diffusion. Our algorithm adapts according to the structure of the photon map such that smoothing occurs along edges and structures and not across. In this way, we preserve important illumination features, while......Density estimation employed in multi-pass global illumination algorithms give cause to a trade-off problem between bias and noise. The problem is seen most evident as blurring of strong illumination features. In particular, this blurring erodes fine structures and sharp lines prominent in caustics...... eliminating noise. We demonstrate the applicability of our algorithm through a series of tests. In the tests, we evaluate the visual and computational performance of our algorithm comparing it to existing popular algorithms. Udgivelsesdato: December...

  14. Touching base with OPERA

    CERN Multimedia

    CERN Bulletin

    2011-01-01

    Three seminars – at CERN, at Gran Sasso and in Japan – and an article calling for the scrutiny of the scientific community: the OPERA Collaboration opened its research publicly. In addition to huge press coverage, this triggered welcome reactions from colleagues around the world, many of whom will attempt to independently interpret and reproduce the measurement. OPERA’s Spokesperson touches base with the Bulletin.   The CERN Main Auditorium was crowded as OPERA Physics co-ordinator Dario Autiero presented the results of their research (23 September 2011). According to the OPERA strategy, the results of the measurements are in the hands of the scientific community and, as for any other scientific result, several months will be needed before other groups will be able to perform an independent measurement. In the meantime, the OPERA Collaboration is dealing with an avalanche of emails from the scientific community, members of the general public, and the press. &...

  15. Base isolation: Fresh insight

    Energy Technology Data Exchange (ETDEWEB)

    Shustov, V.

    1993-07-15

    The objective of the research is a further development of the engineering concept of seismic isolation. Neglecting the transient stage of seismic loading results in a widespread misjudgement: The force of resistance associated with velocity is mostly conceived as a source of damping vibrations, though it is an active force at the same time, during an earthquake type excitation. For very pliant systems such as base isolated structures with relatively low bearing stiffness and with artificially added heavy damping mechanism, the so called `damping`` force may occur even the main pushing force at an earthquake. Thus, one of the two basic pillars of the common seismic isolation philosophy, namely, the doctrine of usefulness and necessity of a strong damping mechanism, is turning out to be a self-deception, sometimes even jeopardizing the safety of structures and discrediting the very idea of seismic isolation. There is a way out: breaking with damping dependancy.

  16. Location-based Scheduling

    DEFF Research Database (Denmark)

    Andersson, Niclas; Christensen, Knud

    The coordination of activities and resources in order to establish an effective production flow is central to the management of construction projects. The traditional technique for coordination of activities and resources in construction projects is the CPM-scheduling, which has been the predomin......The coordination of activities and resources in order to establish an effective production flow is central to the management of construction projects. The traditional technique for coordination of activities and resources in construction projects is the CPM-scheduling, which has been...... on the market. However, CPM is primarily an activity based method that takes the activity as the unit of focus and there is criticism raised, specifically in the case of construction projects, on the method for deficient management of construction work and continuous flow of resources. To seek solutions...

  17. Bases para proyectiles dirigidos

    Directory of Open Access Journals (Sweden)

    Editorial, Equipo

    1959-03-01

    Full Text Available Aunque actualmente no se ha llegado a una línea general de métodos o sistemas que gobiernen un tipo característico de rampa y servicios auxiliares necesarios para el lanzamiento al espacio de proyectiles dirigidos a grandes alturas y distancias, las experiencias obtenidas en diferentes ensayos, utilizando distintos tipos de proyectiles y trayectorias balísticas, han sentado toda una serie de procedimientos, datos y conclusiones de gran valor balístico que, aun teniendo en cuenta la continua evolución del proyectil, sus formas, combustibles y alcances, se conocen ya, con bastante aproximación, las condiciones mínimas que ha de reunir una base dedicada a este tipo de lanzamientos.

  18. Al - BASED CAST COMPOSITES

    Directory of Open Access Journals (Sweden)

    Rakesh Kumar Yadav

    2011-08-01

    Full Text Available The economy is very important feature nowadays in themarket. The researches are playing an important role inengineering field to increase the life of machine parts /components and decrease the cost. The compositematerials have the potential to replace widely used steeland aluminium due to their good characteristics withbetter performance. The Al-based composites have foundextensive applications in automobile industries andaerospace industries due to their increased stiffness,strength, thermal conductivity and wear resistanceproperties. A number of particulate phases have beenemployed in the Al-alloy matrix. The cast aluminiumceramicparticulate composites are finding applications inpistons, connecting rods, cylinder liner, engine cylinderblock, electrical contacts etc.The present investigation isbased on study of the effect of particulate phase on theSEM study, micro-hardness, elastic modulus, tensilestrength and the wear behaviour of Al-5 % SiC-7 % Fe,Al-10 % SiC-6 % Fe and Al-15 % SiC-5 % Fe composites.

  19. The office based CHIVA

    Directory of Open Access Journals (Sweden)

    Passariello F

    2013-09-01

    Full Text Available Fausto Passariello,1 Stefano Ermini,2 Massimo Cappelli,3 Roberto Delfrate,4 Claude Franceschi5 1Centro Diagnostico Aquarius, Napoli, Italy; 2Private Practice, Grassina, Italy; 3Private Practice, Firenze, Italy; 4Casa di Cure Figlie di Maria, Cremona, Italy; 5Hospital St Joseph, Service d'Explorations Vasculaires, Paris, France Abstract: The cure Conservatrice Hémodynamique de l'Insuffisance Veineuse en Ambulatoire (CHIVA can be office based (OB. The OB-CHIVA protocol is aimed at transferring CHIVA procedures to specialists rooms. The protocol will check the feasibility of OB-CHIVA, data pertaining to recurrence, and will offer the opportunity to study saphenous femoral junction (SFJ stump evolution, the role of the washing vessels and the arch recanalization rate, and gather new data about the effect of the length of the treated saphenous vein. A simplified diagnostic procedure will allow an essential ultrasound examination of the venous net while a schematic and easily readable algorithm guides therapeutic choices. The Riobamba draining crossotomy (RDC tactic is composed of a set of OB procedures. While some of these procedures are, at the moment, only proposals, others are already applied. Devices generally used in ablative procedures such as Light Amplification by Stimulated Emission of Radiation (LASER, radio frequency, steam, and mechanical devices are used in this context to serve to conservative interventions for CHIVA. New techniques have also been proposed for devalvulation and tributary disconnection. Detailed follow-up is necessary in order to determine the effects of therapy and possible disease evolution. Finally, information is added about the informed consent and the ethical considerations of OB-CHIVA research. Keywords: CHIVA, office based procedures, LASER, RF, steam

  20. Base Research Program

    Energy Technology Data Exchange (ETDEWEB)

    Everett Sondreal; John Hendrikson

    2009-03-31

    In June 2009, the Energy & Environmental Research Center (EERC) completed 11 years of research under the U.S. Department of Energy (DOE) Base Cooperative Agreement No. DE-FC26-98FT40320 funded through the Office of Fossil Energy (OFE) and administered at the National Energy Technology Laboratory (NETL). A wide range of diverse research activities were performed under annual program plans approved by NETL in seven major task areas: (1) resource characterization and waste management, (2) air quality assessment and control, (3) advanced power systems, (4) advanced fuel forms, (5) value-added coproducts, (6) advanced materials, and (7) strategic studies. This report summarizes results of the 67 research subtasks and an additional 50 strategic studies. Selected highlights in the executive summary illustrate the contribution of the research to the energy industry in areas not adequately addressed by the private sector alone. During the period of performance of the agreement, concerns have mounted over the impact of carbon emissions on climate change, and new programs have been initiated by DOE to ensure that fossil fuel resources along with renewable resources can continue to supply the nation's transportation fuel and electric power. The agreement has addressed DOE goals for reductions in CO{sub 2} emissions through efficiency, capture, and sequestration while expanding the supply and use of domestic energy resources for energy security. It has further contributed to goals for near-zero emissions from highly efficient coal-fired power plants; environmental control capabilities for SO{sub 2}, NO{sub x}, fine respirable particulate (PM{sub 2.5}), and mercury; alternative transportation fuels including liquid synfuels and hydrogen; and synergistic integration of fossil and renewable resources (e.g., wind-, biomass-, and coal-based electrical generation).

  1. Usability Issues in Content Based Multimedia Computer Based Trainings

    OpenAIRE

    Khan, Muhammad Qasim; Rehman, Zia ur

    2009-01-01

    In distance education, students and teachers are at different places and interact with each other with the help of different technologies. Broadcast television, two-way video conferencing, asynchronous learning mode, virtual learning environment (VLE) and content based multimedia computer based trainings (CB-MCBTs) are some of the technologies used to provide distance education. Content Based Multimedia Computer Based Trainings (CB-MCBT) is a computerized learning environment. The acceptance ...

  2. DUAL BASES FOR A NEW FAMILY OF GENERALIZED BALL BASES

    Institute of Scientific and Technical Information of China (English)

    Hong-yiWu

    2004-01-01

    This paper presents the dual bases for a new family of generalized Ball curves with a position parameter K, which includes the Bezier curve, generalized Said-Ball curve and some intermediate curves. Using the dual bases, the relative Marsden identity, conversion formulas of bases and control points of various curves are obtained.

  3. The Activity-Based Approach

    OpenAIRE

    McNally, Michael G.; Rindt, Craig

    2008-01-01

    What is the activity-based approach (ABA) and how does it differ from the conventional trip-based model of travel behavior? From where has the activity approach evolved, what is its current status, and what are its potential applications in transportation forecasting and policy analysis. What have been the contributions of activity-based approaches to understanding travel behavior? The conventional trip-based model of travel demand forecasting (see Chapters 2 and 3) has always lacked...

  4. ‘"Education-based Research"

    DEFF Research Database (Denmark)

    Degn Johansson, Troels

    This paper lays out a concept of education-based research-the production of research knowledge within the framework of tertiary design education-as an integration of problem-based learning and research-based education. This leads to a critique of reflective practice as the primary way to facilitate...... learning at this level, a discussion of the nature of design problems in the instrumentalist tradition, and some suggestions as to how design studies curricula may facilitate education-based research....

  5. Identity-based ring signature scheme based on quadratic residues

    Institute of Scientific and Technical Information of China (English)

    Xiong Hu; Qin Zhiguang; Li Fagen

    2009-01-01

    Identity-based (ID-based) ring signature has drawn great concerns in recent years and many ID-based ring signature schemes have been proposed until now. Unfortunately, all of these ID-based ring signatures are constructed from bilinear pairings, a powerful but computationally expensive primitive. Hence, ID-based ring signature without pairing is of great interest in the field of cryptography. In this paper, the authors firstly propose an ID-based ring signature scheme based on quadratic residues. The proposed scheme is proved to be existentially unforgeable against adaptive chosen message-and-identity attack under the random oracle model, assuming the hardness of factoring. The proposed scheme is more efficient than those which are constructed from bilinear pairings.

  6. Managing the Gap between Curriculum Based and Problem Based Learning

    DEFF Research Database (Denmark)

    Bygholm, Ann; Buus, Lillian

    2009-01-01

    /or but rather both/and. In this paper we describe an approach to design and delivery of online courses in computer science which on the one hand is based on a specified curriculum and on the other hand gives room for different learning strategies, problem based learning being one of them. We discuss......Traditionally there has been a clear distinction between curriculum based and problem based approaches to accomplish learning. Preferred approaches depend of course on conviction, culture, traditions and also on the specific learning situation. We will argue that it is not a question of either...... the challenges in applying problem based learning strategies in a context where several universities, with different cultures of teaching, collaboratively develop and deliver online courses. We present a pedagogical framework embracing both problem based and curriculum based strategies and show how we used...

  7. Explanation-Based Auditing

    CERN Document Server

    Fabbri, Daniel

    2011-01-01

    To comply with emerging privacy laws and regulations, it has become common for applications like electronic health records systems (EHRs) to collect access logs, which record each time a user (e.g., a hospital employee) accesses a piece of sensitive data (e.g., a patient record). Using the access log, it is easy to answer simple queries (e.g., Who accessed Alice's medical record?), but this often does not provide enough information. In addition to learning who accessed their medical records, patients will likely want to understand why each access occurred. In this paper, we introduce the problem of generating explanations for individual records in an access log. The problem is motivated by user-centric auditing applications, and it also provides a novel approach to misuse detection. We develop a framework for modeling explanations which is based on a fundamental observation: For certain classes of databases, including EHRs, the reason for most data accesses can be inferred from data stored elsewhere in the da...

  8. Electroencephalography-based monitors

    Directory of Open Access Journals (Sweden)

    Nidhi Gupta

    2015-01-01

    Full Text Available An electroencephalogram (EEG, detects changes and abnormalities in the electrical activity of the brain and thus provides a way to dynamically assess brain function. EEG may be used to diagnose and manage a number of clinical conditions such as epilepsy, convulsive and non-convulsive status epilepticus, encephalitis, barbiturate coma, brain death, etc., EEG provides a large amount of information to the anaesthesiologist for routine clinical practice as depth of anaesthesia monitors and detection of sub-clinical seizures; and also for understanding the complex mechanisms of anaesthesia-induced alteration of consciousness. In the initial years, the routine clinical applicability of EEG was hindered by the complexity of the raw EEG signal. However, with technological advancement, several EEG-derived dimensionless indices have been developed that correlate with the depth of the hypnotic component of anaesthesia and are easy to interpret. Similarly, with the development of quantitative EEG tools, the routine use of continuous EEG is ever expanding in the Intensive Care Units. This review, describe various commonly used EEG-based monitors and their clinical applicability in the field of anaesthesia and critical care.

  9. RF Based Spy

    Directory of Open Access Journals (Sweden)

    Robot Prerna Jain

    2014-04-01

    Full Text Available The intention of this paper is to reduce human victims in terrorist attack such as 26/11. So this problem can be overcome by designing the RF based spy robot which involves wireless camera. so that from this we can examine rivals when it required. This robot can quietly enter into enemy area and sends us the information via wireless camera. On the other hand one more feature is added in this robot that is colour sensor. Colour sensor senses the colour of surface and according to that robot will change its colour. Because of this feature this robot can’t easily detected by enemies. The movement of this robot is wirelessly controlled by a hand held RF transmitter to send commands to the RF receiver mounted on the moving robot. Since human life is always Valueable, these robots are the substitution of soldiers in war areas. This spy robot can also be used in star hotels, shopping malls, jewelry show rooms, etc where there can be threat from intruders or terrorists.

  10. Geovisualization based upon KML

    Directory of Open Access Journals (Sweden)

    Marianna Zichar

    2012-06-01

    Full Text Available The extension kml refers to a human readable file format that is based on a markup language deriving from XML and became rather popular mainly due to Google Earth. This type of files uses not only the classical geometric data, but coordinates of longitude and latitude (in case of 3D system also coordinate of altitude to visualize the different geographically referenced objects, phenomena and processes. Nowadays more than 10 millions of kml files can be accessed via the internet, and this number is still increasing. However, knowledge of the standard features of kml is not always sufficient, because the circumstances of its application influence its usage. The functionality of the APIs for the web-embeddable Google Maps and Google Earth programs is determinative concerning this issue. The elements of the standard KML cannot be always used without any change, but the clever usage of the API can result effective tools of dynamism. My aim is to review how wide the range of kml files application is, to describe their differences and to share some personal experiences.

  11. Mixture Based Outlier Filtration

    Directory of Open Access Journals (Sweden)

    P. Pecherková

    2006-01-01

    Full Text Available Success/failure of adaptive control algorithms – especially those designed using the Linear Quadratic Gaussian criterion – depends on the quality of the process data used for model identification. One of the most harmful types of process data corruptions are outliers, i.e. ‘wrong data’ lying far away from the range of real data. The presence of outliers in the data negatively affects an estimation of the dynamics of the system. This effect is magnified when the outliers are grouped into blocks. In this paper, we propose an algorithm for outlier detection and removal. It is based on modelling the corrupted data by a two-component probabilistic mixture. The first component of the mixture models uncorrupted process data, while the second models outliers. When the outlier component is detected to be active, a prediction from the uncorrupted data component is computed and used as a reconstruction of the observed data. The resulting reconstruction filter is compared to standard methods on simulated and real data. The filter exhibits excellent properties, especially in the case of blocks of outliers. 

  12. Alphavirus-Based Vaccines

    Directory of Open Access Journals (Sweden)

    Kenneth Lundstrom

    2014-06-01

    Full Text Available Alphavirus vectors have demonstrated high levels of transient heterologous gene expression both in vitro and in vivo and, therefore, possess attractive features for vaccine development. The most commonly used delivery vectors are based on three single-stranded encapsulated alphaviruses, namely Semliki Forest virus, Sindbis virus and Venezuelan equine encephalitis virus. Alphavirus vectors have been applied as replication-deficient recombinant viral particles and, more recently, as replication-proficient particles. Moreover, in vitro transcribed RNA, as well as layered DNA vectors have been applied for immunization. A large number of highly immunogenic viral structural proteins expressed from alphavirus vectors have elicited strong neutralizing antibody responses in multispecies animal models. Furthermore, immunization studies have demonstrated robust protection against challenges with lethal doses of virus in rodents and primates. Similarly, vaccination with alphavirus vectors expressing tumor antigens resulted in prophylactic protection against challenges with tumor-inducing cancerous cells. As certain alphaviruses, such as Chikungunya virus, have been associated with epidemics in animals and humans, attention has also been paid to the development of vaccines against alphaviruses themselves. Recent progress in alphavirus vector development and vaccine technology has allowed conducting clinical trials in humans.

  13. Holography based super resolution

    Science.gov (United States)

    Hussain, Anwar; Mudassar, Asloob A.

    2012-05-01

    This paper describes the simulation of a simple technique of superresolution based on holographic imaging in spectral domain. The input beam assembly containing 25 optical fibers with different orientations and positions is placed to illuminate the object in the 4f optical system. The position and orientation of each fiber is calculated with respect to the central fiber in the array. The positions and orientations of the fibers are related to the shift of object spectrum at aperture plane. During the imaging process each fiber is operated once in the whole procedure to illuminate the input object transparency which gives shift to the object spectrum in the spectral domain. This shift of the spectrum is equal to the integral multiple of the pass band aperture width. During the operation of single fiber (ON-state) all other fibers are in OFF-state at that time. The hologram recorded by each fiber at the CCD plane is stored in computer memory. At the end of illumination process total 25 holograms are recorded by the whole fiber array and by applying some post processing and specific algorithm single super resolved image is obtained. The superresolved image is five times better than the band-limited image. The work is demonstrated using computer simulation only.

  14. Scintillator based beta batteries

    Science.gov (United States)

    Rensing, Noa M.; Tiernan, Timothy C.; Shirwadkar, Urmila; O'Dougherty, Patrick; Freed, Sara; Hawrami, Rastgo; Squillante, Michael R.

    2013-05-01

    Some long-term, remote applications do not have access to conventional harvestable energy in the form of solar radiation (or other ambient light), wind, environmental vibration, or wave motion. Radiation Monitoring Devices, Inc. (RMD) is carrying out research to address the most challenging applications that need power for many months or years and which have undependable or no access to environmental energy. Radioisotopes are an attractive candidate for this energy source, as they can offer a very high energy density combined with a long lifetime. Both large scale nuclear power plants and radiothermal generators are based on converting nuclear energy to heat, but do not scale well to small sizes. Furthermore, thermo-mechanical power plants depend on moving parts, and RTG's suffer from low efficiency. To address the need for compact nuclear power devices, RMD is developing a novel beta battery, in which the beta emissions from a radioisotope are converted to visible light in a scintillator and then the visible light is converted to electrical power in a photodiode. By incorporating 90Sr into the scintillator SrI2 and coupling the material to a wavelength-matched solar cell, we will create a scalable, compact power source capable of supplying milliwatts to several watts of power over a period of up to 30 years. We will present the latest results of radiation damage studies and materials processing development efforts, and discuss how these factors interact to set the operating life and energy density of the device.

  15. Securing web-based exams

    NARCIS (Netherlands)

    Sessink, O.D.T.; Beeftink, H.H.; Tramper, J.; Hartog, R.J.M.

    2004-01-01

    Learning management systems may offer web-based exam facilities. Such facilities entail a higher risk to exams fraud than traditional paper-based exams. The article discusses security issues with web-based exams, and proposes precautionary measures to reduce the risks. A security model is presented

  16. PMIS: Data Base Design Report

    Science.gov (United States)

    Fiddleman, Richard; Gorman, Michael M.

    1972-01-01

    PMIS is a computer-based planning and management information system for local school districts. This report centers on the PMIS data bases that contain school system data by reviewing the major phases involved in their creation, explaining the factors that caused the unique orientation of the data bases, reviewing the two tasks that comprise the…

  17. Image Data Bases on Campus.

    Science.gov (United States)

    Kaplan, Reid; Mathieson, Gordon

    1989-01-01

    A description of how image database technology was used to develop two prototypes for academic and administrative applications at Yale University, one using a video data base integration and the other using document-scanning data base technology, is presented. Technical underpinnings for the creation of data bases are described. (Author/MLW)

  18. Facilitating institutional change in West Africa: the CoS–SIS experience

    OpenAIRE

    Adjei-Nsiah, S.; O. Sakyi-Dawson; Klerkx, L.W.A.

    2014-01-01

    The Convergence of Sciences–Strengthening Innovation Systems (CoS–SIS) programme is based on the premise that the livelihood of the African smallholder farmer is constrained by the existence and/or performance of formal and informal institutions that are not conducive to small-farm development. CoS–SIS employs nine platforms in Ghana, Benin and Mali – “Concertation and Innovation Groups” (CIGs) – that aim to facilitate institutional change above the farm level (e.g. rules and regulations, byl...

  19. Facile Growth of Cu2ZnSnS4 Thin-Film by One-Step Pulsed Hybrid Electrophoretic and Electroplating Deposition

    OpenAIRE

    Hung-Wei Tsai; Chia-Wei Chen; Thomas, Stuart R.; Cheng-Hung Hsu; Wen-Chi Tsai; Yu-Ze Chen; Yi-Chung Wang; Zhiming M Wang; Hwen-Fen Hong; Yu-Lun Chueh

    2016-01-01

    The use of costly and rare metals such as indium and gallium in Cu(In,Ga)Se2 (CIGS) based solar cells has motivated research into the use of Cu2ZnSnS4 (CZTS) as a suitable replacement due to its non-toxicity, abundance of compositional elements and excellent optical properties (1.5 eV direct band gap and absorption coefficient of ~104 cm−1). In this study, we demonstrate a one-step pulsed hybrid electrodeposition method (PHED), which combines electrophoretic and electroplating deposition to d...

  20. Solution-Processing of Chalcogenide Nanoparticles and Thin Films for Photovoltaic Applications

    OpenAIRE

    Carreté, Àlex

    2015-01-01

    Tesi realitzada a l'Instut de Recerca en Energia de Catalunya – IREC Thin film solar cells based on direct band gap semiconductors have attracted much research during last decades. Thin film technologies are currently commercial and display record power conversion efficiencies up to 20% at the laboratory scale. However, typical direct band gap semiconductors, CdTe and CuIn1-xGaxS2 (CIGS), content scarce and/or toxic elements such as In, Ga or Cd. An alternative to these materials is Cu2ZnS...

  1. Kësterite thin films for photovoltaics : a review

    OpenAIRE

    Delbos S.

    2012-01-01

    In the years to come, electricity production is bound to increase, and Cu2ZnSn(S, Se)4 (CZTS) compounds, due to their suitability to thin-film solar cells, could be a means to fulfill the demand. After explaining the reasons of the sudden interest of the CIGS scientific community for CZTS solar cells, this paper reviews recent papers published on the subject of kësterites-based solar cells. After a description of crystallographic and optoelectronic properties, including CZTS crystalline struc...

  2. Molecular gas properties of the most isolated galaxies

    OpenAIRE

    Lisenfeld, Ute; Espada, D.; Verdes-Montenegro, L.; Kuno, N.; AMIGA (team)

    2009-01-01

    The AMIGA project: The role of nature vs. nurture for the properties and evolution of galaxies is still an open question. In order to find answers, it is crucial to have a well-selected sample of isolated galaxies as a baseline and comparison. We built, refined and analised such a sample in the project AMIGA ("Analysis of the Interstellar Medium of Isolated GAlaxies???, http://www.iaa.es/AMIGA.html). The sample is based on the Catalogue of Isolated Galaxies (CIG) by Karanchenseva ...

  3. Military Bases and Conservation Markets

    Energy Technology Data Exchange (ETDEWEB)

    Mark Ankeny

    2007-09-01

    Over time, DoD is likely to be one of the largest buyers and sellers in a water quality trading market. The Department of Defense (DoD) operates military bases that resemble small cities in infrastructure. As units redeploy, bases are likely to find themselves well within their environmental limits at the originating base and potentially bumping against limits such as nitrate and phosphate loading at the destination base. Stricter rules and heavier loadings in growing watersheds also present challenges to local bases and municipalities as regulators clamp down on loadings from existing Waste Water Treatment Plants (WWTPs) to meet water quality standards.

  4. Nanoparticle-based Sensors

    Directory of Open Access Journals (Sweden)

    V.K. Khanna

    2008-09-01

    Full Text Available Nanoparticles exhibit several unique properties that can be applied to develop chemical and biosensorspossessing desirable features like enhanced sensitivity and lower detection limits. Gold nanoparticles arecoated with sugars tailored to recognise different biological substances. When mixed with a weak solution ofthe sugar-coated nanoparticles, the target substance, e.g., ricin or E.coli, attaches to the sugar, thereby alteringits properties and changing the colour. Spores of bacterium labeled with carbon dots have been found to glowupon illumination when viewed with a confocal microscope. Enzyme/nanoparticle-based optical sensors forthe detection of organophosphate (OP compounds employ nanoparticle-modified fluorescence of an inhibitorof the enzyme to generate the signal for the OP compound detection. Nanoparticles shaped as nanoprisms,built of silver atoms, appear red on exposure to light. These nanoparticles are used as diagnostic labels thatglow when target DNA, e.g., those of anthrax or HIV, are present. Of great importance are tools like goldnanoparticle-enhanced surface-plasmon resonance sensor and silver nanoparticle surface-enhanced portableRaman integrated tunable sensor. Nanoparticle metal oxide chemiresistors using micro electro mechanical systemhotplate are very promising devices for toxic gas sensing. Chemiresistors comprising thin films of nanogoldparticles, encapsulated in monomolecular layers of functionalised alkanethiols, deposited on interdigitatedmicroelectrodes, show resistance changes through reversible absorption of vapours of harmful gases. Thispaper reviews the state-of-the-art sensors for chemical and biological terror agents, indicates their capabilitiesand applications, and presents the future scope of these devices.Defence Science Journal, 2008, 58(5, pp.608-616, DOI:http://dx.doi.org/10.14429/dsj.58.1683

  5. Lunar Base Heat Pump

    Science.gov (United States)

    Walker, D.; Fischbach, D.; Tetreault, R.

    1996-01-01

    The objective of this project was to investigate the feasibility of constructing a heat pump suitable for use as a heat rejection device in applications such as a lunar base. In this situation, direct heat rejection through the use of radiators is not possible at a temperature suitable for lde support systems. Initial analysis of a heat pump of this type called for a temperature lift of approximately 378 deg. K, which is considerably higher than is commonly called for in HVAC and refrigeration applications where heat pumps are most often employed. Also because of the variation of the rejection temperature (from 100 to 381 deg. K), extreme flexibility in the configuration and operation of the heat pump is required. A three-stage compression cycle using a refrigerant such as CFC-11 or HCFC-123 was formulated with operation possible with one, two or three stages of compression. Also, to meet the redundancy requirements, compression was divided up over multiple compressors in each stage. A control scheme was devised that allowed these multiple compressors to be operated as required so that the heat pump could perform with variable heat loads and rejection conditions. A prototype heat pump was designed and constructed to investigate the key elements of the high-lift heat pump concept. Control software was written and implemented in the prototype to allow fully automatic operation. The heat pump was capable of operation over a wide range of rejection temperatures and cooling loads, while maintaining cooling water temperature well within the required specification of 40 deg. C +/- 1.7 deg. C. This performance was verified through testing.

  6. Soy-based renoprotection.

    Science.gov (United States)

    McGraw, Nancy J; Krul, Elaine S; Grunz-Borgmann, Elizabeth; Parrish, Alan R

    2016-05-01

    Chronic kidney disease (CKD) is a significant public health problem as risk factors such as advanced age, obesity, hypertension and diabetes rise in the global population. Currently there are no effective pharmacologic treatments for this disease. The role of diet is important for slowing the progression of CKD and managing symptoms in later stages of renal insufficiency. While low protein diets are generally recommended, maintaining adequate levels of intake is critical for health. There is an increasing appreciation that the source of protein may also be important. Soybean protein has been the most extensively studied plant-based protein in subjects with kidney disease and has demonstrated renal protective properties in a number of clinical studies. Soy protein consumption has been shown to slow the decline in estimated glomerular filtration rate and significantly improve proteinuria in diabetic and non-diabetic patients with nephropathy. Soy's beneficial effects on renal function may also result from its impact on certain physiological risk factors for CKD such as dyslipidemia, hypertension and hyperglycemia. Soy intake is also associated with improvements in antioxidant status and systemic inflammation in early and late stage CKD patients. Studies conducted in animal models have helped to identify the underlying molecular mechanisms that may play a role in the positive effects of soy protein on renal parameters in polycystic kidney disease, metabolically-induced kidney dysfunction and age-associated progressive nephropathy. Despite the established relationship between soy and renoprotection, further studies are needed for a clear understanding of the role of the cellular and molecular target(s) of soy protein in maintaining renal function. PMID:27152261

  7. Telemetry-Based Ranging

    Science.gov (United States)

    Hamkins, Jon; Vilnrotter, Victor A.; Andrews, Kenneth S.; Shambayati, Shervin

    2011-01-01

    A telemetry-based ranging scheme was developed in which the downlink ranging signal is eliminated, and the range is computed directly from the downlink telemetry signal. This is the first Deep Space Network (DSN) ranging technology that does not require the spacecraft to transmit a separate ranging signal. By contrast, the evolutionary ranging techniques used over the years by NASA missions, including sequential ranging (transmission of a sequence of sinusoids) and PN-ranging (transmission of a pseudo-noise sequence) whether regenerative (spacecraft acquires, then regenerates and retransmits a noise-free ranging signal) or transparent (spacecraft feeds the noisy demodulated uplink ranging signal into the downlink phase modulator) relied on spacecraft power and bandwidth to transmit an explicit ranging signal. The state of the art in ranging is described in an emerging CCSDS (Consultative Committee for Space Data Systems) standard, in which a pseudo-noise (PN) sequence is transmitted from the ground to the spacecraft, acquired onboard, and the PN sequence is coherently retransmitted back to the ground, where a delay measurement is made between the uplink and downlink signals. In this work, the telemetry signal is aligned with the uplink PN code epoch. The ground station computes the delay between the uplink signal transmission and the received downlink telemetry. Such a computation is feasible because symbol synchronizability is already an integral part of the telemetry design. Under existing technology, the telemetry signal cannot be used for ranging because its arrival-time information is not coherent with any Earth reference signal. By introducing this coherence, and performing joint telemetry detection and arrival-time estimation on the ground, a high-rate telemetry signal can provide all the precision necessary for spacecraft ranging.

  8. Space-based detectors

    Science.gov (United States)

    Sesana, A.; Weber, W. J.; Killow, C. J.; Perreur-Lloyd, M.; Robertson, D. I.; Ward, H.; Fitzsimons, E. D.; Bryant, J.; Cruise, A. M.; Dixon, G.; Hoyland, D.; Smith, D.; Bogenstahl, J.; McNamara, P. W.; Gerndt, R.; Flatscher, R.; Hechenblaikner, G.; Hewitson, M.; Gerberding, O.; Barke, S.; Brause, N.; Bykov, I.; Danzmann, K.; Enggaard, A.; Gianolio, A.; Vendt Hansen, T.; Heinzel, G.; Hornstrup, A.; Jennrich, O.; Kullmann, J.; Møller-Pedersen, S.; Rasmussen, T.; Reiche, J.; Sodnik, Z.; Suess, M.; Armano, M.; Sumner, T.; Bender, P. L.; Akutsu, T.; Sathyaprakash, B. S.

    2014-12-01

    The parallel session C5 on Space-Based Detectors gave a broad overview over the planned space missions related to gravitational wave detection. Overviews of the revolutionary science to be expected from LISA was given by Alberto Sesana and Sasha Buchman. The launch of LISA Pathfinder (LPF) is planned for 2015. This mission and its payload "LISA Technology Package" will demonstrate key technologies for LISA. In this context, reference masses in free fall for LISA, and gravitational physics in general, was described by William Weber, laser interferometry at the pico-metre level and the optical bench of LPF was presented by Christian Killow and the performance of the LPF optical metrology system by Paul McNamara. While LPF will not yet be sensitive to gravitational waves, it may nevertheless be used to explore fundamental physics questions, which was discussed by Michele Armano. Some parts of the LISA technology that are not going to be demonstrated by LPF, but under intensive development at the moment, were presented by Oliver Jennrich and Oliver Gerberding. Looking into the future, Japan is studying the design of a mid-frequency detector called DECIGO, which was discussed by Tomotada Akutsu. Using atom interferometry for gravitational wave detection has also been recently proposed, and it was critically reviewed by Peter Bender. In the nearer future, the launch of GRACE Follow-On (for Earth gravity observation) is scheduled for 2017, and it will include a Laser Ranging Interferometer as technology demonstrator. This will be the first inter-spacecraft laser interferometer and has many aspects in common with the LISA long arm, as discussed by Andrew Sutton.

  9. From oil-based mud to water-based mud

    International Nuclear Information System (INIS)

    Maersk Olie og Gas AS has used low toxic oil-based muds extensively since 1982 for drilling development wells and later in the development of horizontal well drilling techniques. However, in view of the strong drive towards a reduction in the amount of oil discharged to the North Sea from the oil industry, Maersk Olie og Gas AS initiated trials with new or improved types of water-based mud, first in deviated wells (1989) and then in horizontal wells (1990). The paper reviews Maersk Olie og Gas As experience with oil-based mud since the drilling of the first horizontal well in 1987, specifically with respect to cuttings washing equipment, oil retention on cuttings, and the procedure for monitoring of this parameter. It describes the circumstances leading to the decision to revert to water-based mud systems. Finally, it reviews the experience gained so far with the new improved types of water-based mud systems, mainly glycol and KCl/polymer mud systems. Comparison of operational data, such as rate of penetration, torque and drag, etc., is made between wells drilled with oil-based mud and water-based mud. The trials with the new improved types of water-based mud systems have been positive, i.e. horizontal wells can be drilled successfully with water-based mud. As a result, Maersk Olie og and Gas AS has decided to discontinue the use of low toxic oil-based muds in the Danish sector of the North Sea

  10. Workplace Based Assessment in Psychiatry

    Directory of Open Access Journals (Sweden)

    Ayse Devrim Basterzi

    2009-11-01

    Full Text Available Workplace based assessment refers to the assessment of working practices based on what doctors actually do in the workplace, and is predominantly carried out in the workplace itself. Assessment drives learning and it is therefore essential that workplace-based assessment focuses on important attributes rather than what is easiest to assess. Workplacebased assessment is usually competency based. Workplace based assesments may well facilitate and enhance various aspects of educational supervisions, including its structure, frequency and duration etc. The structure and content of workplace based assesments should be monitored to ensure that its benefits are maximised by remaining tailored to individual trainees' needs. Workplace based assesment should be used for formative and summative assessments. Several formative assessment methods have been developed for use in the workplace such as mini clinical evaluation exercise (mini-cex, evidence based journal club assesment and case based discussion, multi source feedback etc. This review discusses the need of workplace based assesments in psychiatry graduate education and introduces some of the work place based assesment methods.

  11. Seguridad en bases de datos

    Directory of Open Access Journals (Sweden)

    Heidy Alina Nuevo León

    2011-11-01

    Full Text Available Los sistemas de base de datos son de gran uso, el cual va desde el uso de bases de datos ligeras, bases de datos en tiempo real (en algunas ocasiones obtenida a partir de la optimización de bases de datos relacionales y bases de datos relacionales con potentes gestores como aplicación proveedora del servicio. En el mundo del software libre existen gran cantidad de gestores de bases de datos, entre los que se encuentran mysql, berkeley db, sqlite y postgresql. Este último con gran número de seguidores y de personas de gran nivel en el mundo del desarrollo libre que contribuyen a su propósito.  El presente trabajo tiene como objetivo principal mostrar mediante una investigación los diferentes mecanismos para realizar la configuración de la seguridad para el gestor de base de datos Postgres

  12. Case-based reasoning: The marriage of knowledge base and data base

    Science.gov (United States)

    Pulaski, Kirt; Casadaban, Cyprian

    1988-01-01

    The coupling of data and knowledge has a synergistic effect when building an intelligent data base. The goal is to integrate the data and knowledge almost to the point of indistinguishability, permitting them to be used interchangeably. Examples given in this paper suggest that Case-Based Reasoning is a more integrated way to link data and knowledge than pure rule-based reasoning.

  13. Knowledge base verification based on enhanced colored petri net

    International Nuclear Information System (INIS)

    Verification is a process aimed at demonstrating whether a system meets it's specified requirements. As expert systems are used in various applications, the knowledge base verification of systems takes an importatn position. The conventional Petri net approach that has been studied recently in order to verify the knowledge base is found that it is inadequate to verify the knowledge base of large and complex system, such as alarm processing system of nuclear power plant. Thus, we propose an improved method that models the knowledge base as enhanced colored Petri net. In this study, we analyze the reachability and the error characteristics of the knowledge base and apply the method to verification of simple knowledge base

  14. Optimal pricing decision model based on activity-based costing

    Institute of Scientific and Technical Information of China (English)

    王福胜; 常庆芳

    2003-01-01

    In order to find out the applicability of the optimal pricing decision model based on conventional costbehavior model after activity-based costing has given strong shock to the conventional cost behavior model andits assumptions, detailed analyses have been made using the activity-based cost behavior and cost-volume-profitanalysis model, and it is concluded from these analyses that the theory behind the construction of optimal pri-cing decision model is still tenable under activity-based costing, but the conventional optimal pricing decisionmodel must be modified as appropriate to the activity-based costing based cost behavior model and cost-volume-profit analysis model, and an optimal pricing decision model is really a product pricing decision model construc-ted by following the economic principle of maximizing profit.

  15. Identity-based signature scheme based on quadratic residues

    Institute of Scientific and Technical Information of China (English)

    CHAI ZhenChuan; CAO ZhenFu; DONG XiaoLei

    2007-01-01

    Identity-based (ID-based) cryptography has drawn great concerns in recent years, and most of ID-based schemes are constructed from bilinear parings. Therefore, ID-based scheme without pairing is of great interest in the field of cryptography. Up to now,there still remains a challenge to construct ID-based signature scheme from quadratic residues. Thus, we aim to meet this challenge by proposing a concrete scheme. In this paper, we first introduce the technique of how to calculate a 2lth root of a quadratic residue, and then give a concrete ID-based signature scheme using such technique.We also prove that our scheme is chosen message and ID secure in the random oracle model, assuming the hardness of factoring.

  16. Knowledge base verification based on enhanced colored petri net

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Hyun; Seong, Poong Hyun [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1997-12-31

    Verification is a process aimed at demonstrating whether a system meets it`s specified requirements. As expert systems are used in various applications, the knowledge base verification of systems takes an important position. The conventional Petri net approach that has been studied recently in order to verify the knowledge base is found that it is inadequate to verify the knowledge base of large and complex system, such as alarm processing system of nuclear power plant. Thus, we propose an improved method that models the knowledge base as enhanced colored Petri net. In this study, we analyze the reachability and the error characteristics of the knowledge base and apply the method to verification of simple knowledge base. 8 refs., 4 figs. (Author)

  17. Evidence-based dentistry.

    Science.gov (United States)

    Chambers, David W

    2010-01-01

    Both panegyric and criticism of evidence-based dentistry tend to be clumsy because the concept is poorly defined. This analysis identifies several contributions to the profession that have been made under the EBD banner. Although the concept of clinicians integrating clinical epidemiology, the wisdom of their practices, and patients' values is powerful, its implementation has been distorted by a too heavy emphasis of computerized searches for research findings that meet the standards of academics. Although EBD advocates enjoy sharing anecdotal accounts of mistakes others have made, faulting others is not proof that one's own position is correct. There is no systematic, high-quality evidence that EBD is effective. The metaphor of a three-legged stool (evidence, experience, values, and integration) is used as an organizing principle. "Best evidence" has become a preoccupation among EBD enthusiasts. That overlong but thinly developed leg of the stool is critiqued from the perspectives of the criteria for evidence, the difference between internal and external validity, the relationship between evidence and decision making, the ambiguous meaning of "best," and the role of reasonable doubt. The strongest leg of the stool is clinical experience. Although bias exists in all observations (including searches for evidence), there are simple procedures that can be employed in practice to increase useful and objective evidence there, and there are dangers in delegating policy regarding allowable treatments to external groups. Patient and practitioner values are the shortest leg of the stool. As they are so little recognized, their integration in EBD is problematic and ethical tensions exist where paternalism privileges science over patient's self-determined best interests. Four potential approaches to integration are suggested, recognizing that there is virtually no literature on how the "seat" of the three-legged stool works or should work. It is likely that most dentists

  18. XML-Based SHINE Knowledge Base Interchange Language

    Science.gov (United States)

    James, Mark; Mackey, Ryan; Tikidjian, Raffi

    2008-01-01

    The SHINE Knowledge Base Interchange Language software has been designed to more efficiently send new knowledge bases to spacecraft that have been embedded with the Spacecraft Health Inference Engine (SHINE) tool. The intention of the behavioral model is to capture most of the information generally associated with a spacecraft functional model, while specifically addressing the needs of execution within SHINE and Livingstone. As such, it has some constructs that are based on one or the other.

  19. ANALYSIS-BASED SPARSE RECONSTRUCTION WITH SYNTHESIS-BASED SOLVERS

    OpenAIRE

    Cleju, Nicolae; Jafari, Maria,; Plumbley, Mark D.

    2012-01-01

    Analysis based reconstruction has recently been introduced as an alternative to the well-known synthesis sparsity model used in a variety of signal processing areas. In this paper we convert the analysis exact-sparse reconstruction problem to an equivalent synthesis recovery problem with a set of additional constraints. We are therefore able to use existing synthesis-based algorithms for analysis-based exact-sparse recovery. We call this the Analysis-By-Synthesis (ABS) approach. We evaluate o...

  20. Graph Cuts based Image Segmentation using Fuzzy Rule Based System

    OpenAIRE

    Khokher, M. R.; A. Ghafoor; A.M. Siddiqui

    2012-01-01

    This work deals with the segmentation of gray scale, color and texture images using graph cuts. From input image, a graph is constructed using intensity, color and texture profiles of the image simultaneously. Based on the nature of image, a fuzzy rule based system is designed to find the weight that should be given to a specific image feature during graph development. The graph obtained from the fuzzy rule based weighted average of different image features is further used in normalized graph...

  1. Game-based versus traditional case-based learning

    Science.gov (United States)

    Telner, Deanna; Bujas-Bobanovic, Maja; Chan, David; Chester, Bob; Marlow, Bernard; Meuser, James; Rothman, Arthur; Harvey, Bart

    2010-01-01

    ABSTRACT OBJECTIVE To evaluate family physicians’ enjoyment of and knowledge gained from game-based learning, compared with traditional case-based learning, in a continuing medical education (CME) event on stroke prevention and management. DESIGN An equivalence trial to determine if game-based learning was as effective as case-based learning in terms of attained knowledge levels. Game questions and small group cases were developed. Participants were randomized to either a game-based or a case-based group and took part in the event. SETTING Ontario provincial family medicine conference. PARTICIPANTS Thirty-two family physicians and 3 senior family medicine residents attending the conference. INTERVENTION Participation in either a game-based or a case-based CME learning group. MAIN OUTCOME MEASURES Scores on 40-item immediate and 3-month posttests of knowledge and a satisfaction survey. RESULTS Results from knowledge testing immediately after the event and 3 months later showed no significant difference in scoring between groups. Participants in the game-based group reported higher levels of satisfaction with the learning experience. CONCLUSION Games provide a novel way of organizing CME events. They might provide more group interaction and discussion, as well as improve recruitment to CME events. They might also provide a forum for interdisciplinary CME. Using games in future CME events appears to be a promising approach to facilitate participant learning. PMID:20841574

  2. Acids and bases solvent effects on acid-base strenght

    CERN Document Server

    Cox, Brian G

    2013-01-01

    Acids and bases are ubiquitous in chemistry. Our understanding of them, however, is dominated by their behaviour in water. Transfer to non-aqueous solvents leads to profound changes in acid-base strengths and to the rates and equilibria of many processes: for example, synthetic reactions involving acids, bases and nucleophiles; isolation of pharmaceutical actives through salt formation; formation of zwitter- ions in amino acids; and chromatographic separation of substrates. This book seeks to enhance our understanding of acids and bases by reviewing and analysing their behaviour in non-aqueous solvents. The behaviour is related where possible to that in water, but correlations and contrasts between solvents are also presented.

  3. Quantum Standard Teleportation Based on the Generic Measurement Bases

    Institute of Scientific and Technical Information of China (English)

    HAOSan-Ru; HOUBo-Yu; XIXiao-Qiang; YUERui-Hong

    2003-01-01

    We study the quantum standard teleportation based on the generic measurement bases. It is shown that the quantum standard teleportation does not depend on the explicit expression of the measurement bases. We have given the correspondence relation between the measurement performed by Alice and the unitary transformation performed by Bob. We also prove that the single particle unknown states and the two-particle unknown cat-like states can be exactly transmitted by means of the generic measurement bases and the correspondence unitary transformations.

  4. Computer-based and web-based radiation safety training

    Energy Technology Data Exchange (ETDEWEB)

    Owen, C., LLNL

    1998-03-01

    The traditional approach to delivering radiation safety training has been to provide a stand-up lecture of the topic, with the possible aid of video, and to repeat the same material periodically. New approaches to meeting training requirements are needed to address the advent of flexible work hours and telecommuting, and to better accommodate individuals learning at their own pace. Computer- based and web-based radiation safety training can provide this alternative. Computer-based and web- based training is an interactive form of learning that the student controls, resulting in enhanced and focused learning at a time most often chosen by the student.

  5. Concurrent array-based queue

    Energy Technology Data Exchange (ETDEWEB)

    Heidelberger, Philip; Steinmacher-Burow, Burkhard

    2015-01-06

    According to one embodiment, a method for implementing an array-based queue in memory of a memory system that includes a controller includes configuring, in the memory, metadata of the array-based queue. The configuring comprises defining, in metadata, an array start location in the memory for the array-based queue, defining, in the metadata, an array size for the array-based queue, defining, in the metadata, a queue top for the array-based queue and defining, in the metadata, a queue bottom for the array-based queue. The method also includes the controller serving a request for an operation on the queue, the request providing the location in the memory of the metadata of the queue.

  6. [The challenge of electronic cigarettes].

    Science.gov (United States)

    Córdoba García, Rodrigo

    2014-01-01

    The electronic cigarette (e-cig) is a device with a conventional cigarette shape that releases a determined dose of nicotine vapour through an electronic heating process. The nicotine cartridges vary significantly in the amount of nicotine released, even within the same brand. Not all brands admit that they contain nicotine, but this is detected in the majority of units analysed. The e-cig usually contains a propellant, such as propylene glycol, which is a lung irritant. The short-term respiratory effect of the vapour of an e-cig is similar to that caused by the smoke of a cigarette, and is a cause of broncho-restriction. The majority of brands contain glycerine and at least one case of lipoid pneumonia has been detected due to this substance. Many brands contain traces of N-nitrosamines, heavy metals, and other products that are found in conventional cigarette smoke, but in a much higher proportion. There is currently no scientific evidence available that shows it is an effective device for quitting smoking, thus it should not be pro-actively recommended for this purpose, and may interfere with the use of demonstrated scientific evidence-based treatments for quitting smoking. It may have an undesirable effect on promoting the starting of smoking in adolescents or keeping adult smokers consuming nicotine and on gestural dependency. The toxicity of the vapour is not well known, but it is known that they are not innocuous, thus they should not be used in closed public spaces. PMID:24704194

  7. Flexible Ultra Moisture Barrier Film for Thin-Film Photovoltaic Applications

    Energy Technology Data Exchange (ETDEWEB)

    David M. Dean

    2012-10-30

    Flexible Thin-film photovoltaic (TFPV) is a low cost alternative to incumbent c-Si PV products as it requires less volume of costly semiconductor materials and it can potentially reduce installation cost. Among the TFPV options, copper indium gallium diselenide (CIGS) has the highest efficiency and is believed to be one of the most attractive candidates to achieve PV cost reduction. However, CIGS cells are very moisture sensitive and require module water vapor transmission rate (WVTR) of less than 1x10-4 gram of water per square meter per day (g-H2O/m2/day). Successful development and commercialization of flexible transparent ultra moisture barrier film is the key to enable flexible CIGS TFPV products, and thus enable ultimate PV cost reduction. At DuPont, we have demonstrated at lab scale that we can successfully make polymer-based flexible transparent ultra moisture barrier film by depositing alumina on polymer films using atomic layer deposition (ALD) technology. The layer by layer ALD approach results in uniform and amorphous structure which effectively reduces pinhole density of the inorganic coating on the polymer, and thus allow the fabrication of flexible barrier film with WVTR of 10-5 g-H2O/m2/day. Currently ALD is a time-consuming process suitable only for high-value, relatively small substrates. To successfully commercialize the ALD-on-plastic technology for the PV industry, there is the need to scale up this technology and improve throughput. The goal of this contract work was to build a prototype demonstrating that the ALD technology could be scaled-up for commercial use. Unfortunately, the prototype failed to produce an ultra-barrier film by the close of the project.

  8. Instantaneous noise-based logic

    OpenAIRE

    Kish, Laszlo B.; Khatri, Sunil; Peper, Ferdinand

    2010-01-01

    We show two universal, Boolean, deterministic logic schemes based on binary noise timefunctions that can be realized without time-averaging units. The first scheme is based on a new bipolar random telegraph wave scheme and the second one makes use of the recent noise-based logic which is conjectured to be the brain's method of logic operations [Physics Letters A 373 (2009) 2338-2342]. Error propagation and error removal issues are also addressed.

  9. Restructuring and simplifying rule bases

    OpenAIRE

    Vanthienen, Jan; Dries, E; WETS, G

    1995-01-01

    Rule bases are commonly acquired, by expert and/or knowledge engineer, in a form which is well suited for acquisition purposes. When the knowledge base is executed, however, a different structure may be required. Moreover, since human experts normally do not provide the knowledge in compact chunks, rule bases often suffer from redundancy. This may considerably harm efficiency. In this paper a procedure is examined to transform rules that are specified in the knowledge acquisition process ...

  10. Principles of models based engineering

    Energy Technology Data Exchange (ETDEWEB)

    Dolin, R.M.; Hefele, J.

    1996-11-01

    This report describes a Models Based Engineering (MBE) philosophy and implementation strategy that has been developed at Los Alamos National Laboratory`s Center for Advanced Engineering Technology. A major theme in this discussion is that models based engineering is an information management technology enabling the development of information driven engineering. Unlike other information management technologies, models based engineering encompasses the breadth of engineering information, from design intent through product definition to consumer application.

  11. dBASE IV basics

    Energy Technology Data Exchange (ETDEWEB)

    O`Connor, P.

    1994-09-01

    This is a user`s manual for dBASE IV. dBASE IV is a popular software application that can be used on your personal computer to help organize and maintain your database files. It is actually a set of tools with which you can create, organize, select and manipulate data in a simple yet effective manner. dBASE IV offers three methods of working with the product: (1) control center: (2) command line; and (3) programming.

  12. Trace-Based Code Generation for Model-Based Testing

    NARCIS (Netherlands)

    Kanstrén, T.; Piel, E.; Gross, H.-G.

    2009-01-01

    Paper Submitted for review at the Eighth International Conference on Generative Programming and Component Engineering. Model-based testing can be a powerful means to generate test cases for the system under test. However, creating a useful model for model-based testing requires expertise in the (fo

  13. Image based Monument Recognition using Graph based Visual Saliency

    DEFF Research Database (Denmark)

    Kalliatakis, Grigorios; Triantafyllidis, Georgios

    2013-01-01

    This article presents an image-based application aiming at simple image classification of well-known monuments in the area of Heraklion, Crete, Greece. This classification takes place by utilizing Graph Based Visual Saliency (GBVS) and employing Scale Invariant Feature Transform (SIFT) or Speeded...

  14. Distributed event-based systems

    CERN Document Server

    Fiege, Ludger; Pietzuch, Peter R

    2006-01-01

    This book provides an in-depth description of event-based systems, covering topics ranging from local event matching and distributed event forwarding algorithms, through a practical discussion of software engineering issues raised by the event-based style, to state-of-the-art research in event-based systems like composite event detection and security. The authors offer a comprehensive overview, and show the power of event-based architectures in modern system design, encouraging professionals to exploit this technique in next generation large-scale distributed applications like information diss

  15. Capability-based computer systems

    CERN Document Server

    Levy, Henry M

    2014-01-01

    Capability-Based Computer Systems focuses on computer programs and their capabilities. The text first elaborates capability- and object-based system concepts, including capability-based systems, object-based approach, and summary. The book then describes early descriptor architectures and explains the Burroughs B5000, Rice University Computer, and Basic Language Machine. The text also focuses on early capability architectures. Dennis and Van Horn's Supervisor; CAL-TSS System; MIT PDP-1 Timesharing System; and Chicago Magic Number Machine are discussed. The book then describes Plessey System 25

  16. Web-based support systems

    CERN Document Server

    Yao, JingTao

    2010-01-01

    The emerging interdisciplinary study of Web-based support systems focuses on the theories, technologies and tools for the design and implementation of Web-based systems that support various human activities. This book presents the state-of-the-art in Web-based support systems (WSS). The research on WSS is multidisciplinary and focuses on supporting various human activities in different domains/fields based on computer science, information technology, and Web technology. The main goal is to take the opportunities of the Web, to meet the challenges of the Web, to extend the human physical limita

  17. Improved growth of solution-deposited thin films on polycrystalline Cu(In,Ga)Se{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Witte, Wolfram; Hariskos, Dimitrios [Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung Baden-Wuerttemberg (ZSW), 70565, Stuttgart (Germany); Abou-Ras, Daniel [Helmholtz-Zentrum Berlin fuer Materialien und Energie, 14109, Berlin (Germany)

    2016-04-15

    CdS and Zn(O,S) grown by chemical bath deposition (CBD) are well established buffer materials for Cu(In,Ga)Se{sub 2} (CIGS) solar cells. As recently reported, a non-contiguous coverage of CBD buffers on CIGS grains with {112} surfaces can be detected, which was explained in terms of low surface energies of the {112} facets, leading to deteriorated wetting of the chemical solution on the CIGS surface. In the present contribution, we report on the effect of air annealing of CIGS thin films prior to the CBD of CdS and Zn(O,S) layers. In contrast to the growth on the as-grown CIGS layers, these buffer lay- ers grow densely on the annealed CIGS layer, even on grains with {112} surfaces. We explain the different growth behavior by increased surface energies of CIGS grains due to the annealing step, i.e., due to oxidation of the CIGS surface. Reference solar cells were processed and completed by i-ZnO/ZnO:Al layers for CdS and by (Zn,Mg)O/ZnO:Al for Zn(O,S) buffers. For solar cells with both, CdS and Zn(O,S) buffers, air-annealed CIGS films with improved buffer coverage resulted in higher power-conversion efficiencies, as compared with the devices containing as-grown CIGS layers. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. Regulation in the face of uncertainty: the evidence on electronic nicotine delivery systems (e-cigarettes

    Directory of Open Access Journals (Sweden)

    Farsalinos KE

    2015-09-01

    Full Text Available Konstantinos E Farsalinos,1,2 Jacques Le Houezec3,4 1Department of Cardiology, Onassis Cardiac Surgery Center, Kallithea, 2Department of Pharmacy, University of Patras, Patras, Greece; 3Division of Epidemiology and Public Health, UK Centre for Tobacco and Alcohol Studies, University of Nottingham, Nottingham, England, UK; 4Addiction Research Unit, INSERM 1178 (Mental and Public Health, Paris, France Abstract: Tobacco smoking is the largest single preventable cause of many chronic diseases and death. Effective treatments exist; however, few smokers use them and most try to quit by themselves. Most of the tobacco cigarette's toxicity is related to the combustion process. Models of harm reduction applied to tobacco suggest that switching from inhalation of combustible products to a noncombustible nicotine delivery product would likely result in a vast reduction in tobacco-related death and illness. Currently available evidence raises no doubt that electronic cigarettes (e-cigs are by far less harmful than smoking (although probably not absolutely safe and have the potential to be the most effective tobacco harm reduction products due to their unique property of resembling smoking and providing satisfaction to the user. A lot of controversy is surrounding e-cigs and their regulation, much of which is based on the precautionary principle. Although monitoring and further research is definitely needed, the arguments used to implement severe restrictions or bans are mostly hypothetical, weakly supported by evidence, and, in some cases, derived from mispresentation or misinterpretation of the study findings. Regulators should keep in mind that the target population is smokers who want to reduce or quit their deadly tobacco consumption. To achieve this goal, smokers should be honestly informed on the relative harmfulness of the different products. E-cigs are not tobacco products and are not used as medications. For this reason, a specific regulatory

  19. Polyurethane Based Inhibition for High Flame Temperature Nitramine Based Composite Modified Double Base propellant

    OpenAIRE

    S. D. Kakade; M. V. Vaidya; D. G. Khangaonkar; P. K. Divekar; U. B. Kadam; S. N. Asthana

    1998-01-01

    The findings for polypropylene glycol (PPG) and hydroxyl-terminated polybutadiene (HTPB)-based inhibition systems are reported. These findings established that the inhibition system comprising HTPB-IPDI-IDP binder and Sb/sub 2/O/sub 3/-C black filler is most suitable for advanced nitramine-based composite modified double-base propellants in terms of mechanical properties and processibility. The promising composition was characterised for glass-transition behaviour and propellant-inhibi...

  20. Wavelength conversion based spectral imaging

    DEFF Research Database (Denmark)

    Dam, Jeppe Seidelin

    resolution for this spectral region. Today, an increasing number of applications exists outside the spectral region covered by Si-based devices, e.g. within cleantech, medical or food imaging. We present a technology based on wavelength conversion which will extend the spectral coverage of state of the art...

  1. Evidence-Based Laboratory Medicine

    Institute of Scientific and Technical Information of China (English)

    Christopher P Price

    2004-01-01

    @@ Whilst there have been several definitions of Evidence-Based Medicine (EBM), the one given by David Sackett is probably the most accurate and well accepted; he stated that "evidence-based medicine is the conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients"[1].

  2. Theory-Based Stakeholder Evaluation

    Science.gov (United States)

    Hansen, Morten Balle; Vedung, Evert

    2010-01-01

    This article introduces a new approach to program theory evaluation called theory-based stakeholder evaluation or the TSE model for short. Most theory-based approaches are program theory driven and some are stakeholder oriented as well. Practically, all of the latter fuse the program perceptions of the various stakeholder groups into one unitary…

  3. Optical Fiber Grating based Sensors

    DEFF Research Database (Denmark)

    Michelsen, Susanne

    2003-01-01

    sampled gratings, was produced and investigated. It is based on the different temperature and strain response of these gratings. Both a transfer matrix method and an overlap calculation is performed to explain the sensor response. Another type of sensor is based on tuning and modulation of a laser...

  4. Knowledge-Based Asynchronous Programming

    NARCIS (Netherlands)

    Haan, Hendrik Wietze de; Hesselink, Wim H.; Renardel de Lavalette, Gerard R.

    2004-01-01

    A knowledge-based program is a high-level description of the behaviour of agents in terms of knowledge that an agent must have before (s)he may perform an action. The definition of the semantics of knowledge-based programs is problematic, since it involves a vicious circle; the knowledge of an agent

  5. Methods in Logic Based Control

    DEFF Research Database (Denmark)

    Christensen, Georg Kronborg

    1999-01-01

    Desing and theory of Logic Based Control systems.Boolean Algebra, Karnaugh Map, Quine McClusky's algorithm. Sequential control design. Logic Based Control Method, Cascade Control Method. Implementation techniques: relay, pneumatic, TTL/CMOS,PAL and PLC- and Soft_PLC implementation. PLC...

  6. Interpretation-Based Grammar Teaching.

    Science.gov (United States)

    Ellis, Rod

    1993-01-01

    In contrast to the usual approach to teaching grammar, this article argues for a comprehension-based approach. Based on a model of second-language acquisition, it examines a number of possible goals for grammar instruction (e.g., to promote "intake" of new grammatical features by helping learners notice input features and comprehend the meaning).…

  7. Team-Based Global Organizations

    DEFF Research Database (Denmark)

    Zander, Lena; Butler, Christina Lea; Mockaitis, Audra;

    2015-01-01

    the global firm. Practical implications-Practitioners can learn about organizational, team, and individual challenges and benefits of global team-based organizing. Originality/value-A century-old dominant organizational form is challenged when moving away from hierarchy-and hybrid-based forms of organizing...

  8. FAST WATERSHED-BASED DILATION

    OpenAIRE

    Jakub Smołka

    2014-01-01

    A watershed-based region growing image segmentation algorithm requires a fast watershed-based dilation implementation for effective operation. This paper presents a new way for watershed image representation and uses this representation for effective implementation of dilation. Methods for improving the algorithm speed are discussed. Presented solutions may also be used for solving other problems where fast set summation is required.

  9. Plasma-based accelerator structures

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Carl B.

    1999-12-01

    Plasma-based accelerators have the ability to sustain extremely large accelerating gradients, with possible high-energy physics applications. This dissertation further develops the theory of plasma-based accelerators by addressing three topics: the performance of a hollow plasma channel as an accelerating structure, the generation of ultrashort electron bunches, and the propagation of laser pulses is underdense plasmas.

  10. Cloud-Based Data Storage

    Science.gov (United States)

    Waters, John K.

    2011-01-01

    The vulnerability and inefficiency of backing up data on-site is prompting school districts to switch to more secure, less troublesome cloud-based options. District auditors are pushing for a better way to back up their data than the on-site, tape-based system that had been used for years. About three years ago, Hendrick School District in…

  11. Plasma-based accelerator structures

    International Nuclear Information System (INIS)

    Plasma-based accelerators have the ability to sustain extremely large accelerating gradients, with possible high-energy physics applications. This dissertation further develops the theory of plasma-based accelerators by addressing three topics: the performance of a hollow plasma channel as an accelerating structure, the generation of ultrashort electron bunches, and the propagation of laser pulses is underdense plasmas

  12. GPP-Based Soft Base Station Designing and Optimization

    Institute of Scientific and Technical Information of China (English)

    Xiao-Feng Tao; Yan-Zhao Hou; Kai-Dong Wang; Hai-Yang He; Y.Jay Guo

    2013-01-01

    It is generally acknowledged that mobile communication base stations are composed of hardware components such as Field Programming Gate Array (FPGA),Digital Signal Processor (DSP),which promise reliable and fluent services for the mobile users.However,with the increasing demand for energy-efficiency,approaches of low power-consumption and high-flexibility are needed urgently.In this circumstance,General Purpose Processor (GPP) attracts people's attention for its low-cost and flexibility.Benefited from the development of modern GPP in multi-core,Single Instruction Multiple Data (SIMD) instructions,larger cache,etc.,GPPs are capable of performing high-density digital processing.In this paper,we compare several software-defined radio (SDR) prototypes and propose the general architecture of GPP-based soft base stations.Then,the schematic design of resource allocation and algorithm optimization in soft base station implementation are studied.As an application example,a prototype of GPP-based soft base station referring to the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) is realized and evaluated.To the best of our knowledge,it is the first Soft-LTE prototype ever reported.In the end,we evaluate the timing performance of the LTE soft base station and a packet loss ratio of less than 0.003 is obtained.

  13. Lignin-Based Thermoplastic Materials.

    Science.gov (United States)

    Wang, Chao; Kelley, Stephen S; Venditti, Richard A

    2016-04-21

    Lignin-based thermoplastic materials have attracted increasing interest as sustainable, cost-effective, and biodegradable alternatives for petroleum-based thermoplastics. As an amorphous thermoplastic material, lignin has a relatively high glass-transition temperature and also undergoes radical-induced self-condensation at high temperatures, which limits its thermal processability. Additionally, lignin-based materials are usually brittle and exhibit poor mechanical properties. To improve the thermoplasticity and mechanical properties of technical lignin, polymers or plasticizers are usually integrated with lignin by blending or chemical modification. This Review attempts to cover the reported approaches towards the development of lignin-based thermoplastic materials on the basis of published information. Approaches reviewed include plasticization, blending with miscible polymers, and chemical modifications by esterification, etherification, polymer grafting, and copolymerization. Those lignin-based thermoplastic materials are expected to show applications as engineering plastics, polymeric foams, thermoplastic elastomers, and carbon-fiber precursors. PMID:27059111

  14. Lignin-Based Thermoplastic Materials.

    Science.gov (United States)

    Wang, Chao; Kelley, Stephen S; Venditti, Richard A

    2016-04-21

    Lignin-based thermoplastic materials have attracted increasing interest as sustainable, cost-effective, and biodegradable alternatives for petroleum-based thermoplastics. As an amorphous thermoplastic material, lignin has a relatively high glass-transition temperature and also undergoes radical-induced self-condensation at high temperatures, which limits its thermal processability. Additionally, lignin-based materials are usually brittle and exhibit poor mechanical properties. To improve the thermoplasticity and mechanical properties of technical lignin, polymers or plasticizers are usually integrated with lignin by blending or chemical modification. This Review attempts to cover the reported approaches towards the development of lignin-based thermoplastic materials on the basis of published information. Approaches reviewed include plasticization, blending with miscible polymers, and chemical modifications by esterification, etherification, polymer grafting, and copolymerization. Those lignin-based thermoplastic materials are expected to show applications as engineering plastics, polymeric foams, thermoplastic elastomers, and carbon-fiber precursors.

  15. Tag Based Audio Search Engine

    Directory of Open Access Journals (Sweden)

    Parameswaran Vellachu

    2012-03-01

    Full Text Available The volume of the music database is increasing day by day. Getting the required song as per the choice of the listener is a big challenge. Hence, it is really hard to manage this huge quantity, in terms of searching, filtering, through the music database. It is surprising to see that the audio and music industry still rely on very simplistic metadata to describe music files. However, while searching audio resource, an efficient "Tag Based Audio Search Engine" is necessary. The current research focuses on two aspects of the musical databases 1. Tag Based Semantic Annotation Generation using the tag based approach.2. An audio search engine, using which the user can retrieve the songs based on the users choice. The proposed method can be used to annotation and retrieve songs based on musical instruments used , mood of the song, theme of the song, singer, music director, artist, film director, instrument, genre or style and so on.

  16. Comparative Study of Triangulation based and Feature based Image Morphing

    Directory of Open Access Journals (Sweden)

    Ms. Bhumika G. Bhatt

    2012-01-01

    Full Text Available Image Morphing is one of the most powerful Digital Image processing technique, which is used to enhancemany multimedia projects, presentations, education and computer based training. It is also used inmedical imaging field to recover features not visible in images by establishing correspondence of featuresamong successive pair of scanned images. This paper discuss what morphing is and implementation ofTriangulation based morphing Technique and Feature based Image Morphing. IT analyze both morphingtechniques in terms of different attributes such as computational complexity, Visual quality of morphobtained and complexity involved in selection of features.

  17. Survey paper on Sketch Based and Content Based Image Retrieval

    OpenAIRE

    Gaidhani, Prachi A.; S. B. Bagal

    2015-01-01

    This survey paper presents an overview of development of Sketch Based Image Retrieval (SBIR) and Content based image retrieval (CBIR) in the past few years. There is awful growth in bulk of images as well as the far-flung application in too many fields. The main attributes to represent as well index the images are color, shape, texture, spatial layout. These features of images are extracted to check similarity among the images. Generation of special query is the main problem of content based ...

  18. Content-Based Image Retrial Based on Hadoop

    Directory of Open Access Journals (Sweden)

    DongSheng Yin

    2013-01-01

    Full Text Available Generally, time complexity of algorithms for content-based image retrial is extremely high. In order to retrieve images on large-scale databases efficiently, a new way for retrieving based on Hadoop distributed framework is proposed. Firstly, a database of images features is built by using Speeded Up Robust Features algorithm and Locality-Sensitive Hashing and then perform the search on Hadoop platform in a parallel way specially designed. Considerable experimental results show that it is able to retrieve images based on content on large-scale cluster and image sets effectively.

  19. Value-based metrics and Internet-based enterprises

    Science.gov (United States)

    Gupta, Krishan M.

    2001-10-01

    Within the last few years, a host of value-based metrics like EVA, MVA, TBR, CFORI, and TSR have evolved. This paper attempts to analyze the validity and applicability of EVA and Balanced Scorecard for Internet based organizations. Despite the collapse of the dot-com model, the firms engaged in e- commerce continue to struggle to find new ways to account for customer-base, technology, employees, knowledge, etc, as part of the value of the firm. While some metrics, like the Balance Scorecard are geared towards internal use, others like EVA are for external use. Value-based metrics are used for performing internal audits as well as comparing firms against one another; and can also be effectively utilized by individuals outside the firm looking to determine if the firm is creating value for its stakeholders.

  20. G -Frames, g -orthonormal bases and g -Riesz bases

    Directory of Open Access Journals (Sweden)

    Seyedeh Sara Karimizad

    2014-05-01

    Full Text Available G-Frames in Hilbert spaces are a redundant set of operators which yield a repre-sentation for each vector in the space. In this paper we investigate the connection betweeng-frames, g-orthonormal bases and g-Riesz bases. We show that a family of bounded opera-tors is a g-Bessel sequences if and only if the Gram matrix associated to its denes a bounded operator

  1. Content-Based Image Retrial Based on Hadoop

    OpenAIRE

    DongSheng Yin; DeBo Liu

    2013-01-01

    Generally, time complexity of algorithms for content-based image retrial is extremely high. In order to retrieve images on large-scale databases efficiently, a new way for retrieving based on Hadoop distributed framework is proposed. Firstly, a database of images features is built by using Speeded Up Robust Features algorithm and Locality-Sensitive Hashing and then perform the search on Hadoop platform in a parallel way specially designed. Considerable experimental results show that it is abl...

  2. Implementation of activity based cost management aboard base installations

    OpenAIRE

    Stanley, James; Perkins, Nicholas R.; Zander, Laura

    2004-01-01

    Approved for public release; distribution is unlimited. MBA Professional Report This project is a comparative analysis of the implementation process of Activity Based Cost Management of Marine Corps Logistics Base, (MCLB), Albany, and the implementation procedures used aboard MCB Camp Lejeune. Interviews and data gathering were conducted to identify how the respective Business Performance Offices (BPO), plan, implement, monitor, and measure performance of their process to introduce ABCM...

  3. Trace-Based Code Generation for Model-Based Testing

    OpenAIRE

    Kanstrén, T.; Piel, E.; Gross, H.-G.

    2009-01-01

    Paper Submitted for review at the Eighth International Conference on Generative Programming and Component Engineering. Model-based testing can be a powerful means to generate test cases for the system under test. However, creating a useful model for model-based testing requires expertise in the (formal) modeling language of the used tool and the general concept of modeling the system under test for effective test generation. A commonly used modeling notation is to describe the model through a...

  4. On Knowledge Excavation Based on University Library Knowledge Base

    OpenAIRE

    Ying Song

    2009-01-01

    Knowledge excavation is a new information processing technology. Nowadays, knowledge excavation has been widely applied to the university library management. Knowledge excavation in university library knowledge bases has already been playing an important role in improving the management of university libraries and inevitably will play a more profound role in the future. In this paper, the meaning of knowledge excavation in university library knowledge bases and other related issues are studie...

  5. Problem-based, interdisciplinary field-based courses

    DEFF Research Database (Denmark)

    Hill, Trevor; Birch-Thomsen, Torben; Traynor, Catherine;

    2008-01-01

    Student field courses at Universities are increasingly incorporating problem-based interdisciplinary approaches to enhance learning opportunities. This paper reports upon seven field-based, problem-oriented, interdisciplinary courses held within southern Africa concerning natural resource...... in a positive manner and a strong respectful working relationship from the staff. We advocate this process as worthwhile as classroom theory becomes real in all applied and complex environment....

  6. Region-based multimodal image fusion using ICA bases

    OpenAIRE

    Cvejic, N; Lewis, J.; Bull, DR; Canagarajah, CN

    2006-01-01

    In this paper, we present a novel region-based multimodal image fusion algorithm in the ICA domain. It uses segmentation to determine the most important regions in the input images and consequently fuses the ICA coefficients from the given regions. The proposed method exhibits considerably higher performance than the basic ICA algorithm and shows improvement over other state-of-the-art algorithms In this paper, we present a novel region-based multimodal image fusion algorithm in the ICA do...

  7. Object-Based Benefits without Object-Based Representations

    OpenAIRE

    Alvarez, George Angelo; Fougnie, Daryl; Cormiea, Sarah M

    2012-01-01

    The organization of visual information into objects strongly influences visual memory: Displays with objects defined by two features (e.g. color, orientation) are easier to remember than displays with twice as many objects defined by one feature (Olson & Jiang, 2002). Existing theories suggest that this ‘object-benefit’ is based on object-based limitations in working memory: because a limited number of objects can be stored, packaging features together so that fewer objects have to be remembe...

  8. Mineral-resource data bases

    Science.gov (United States)

    ,

    1997-01-01

    Data bases are essential for modern scientific research. The new and exciting work being done in the Mineral Resource Program in the U.S. Geological Survey (USGS) usually begins with the question, "Where are the known deposits?" A mineral-resource data base containing this type of information and more can be useful not just to USGS scientists, but to anyone who needs such data. Users of the data bases from outside the USGS include mining and exploration companies, environmental groups, academia, other Federal Agencies, and the general public. At present, the USGS has two large mineral-resource data bases, MRDS (Mineral Resource Data System) and MAS (Minerals Availability System). MRDS was built and is mamtained by the USGS, and MAS was built and maintained by the Bureau of Mines. In 1996, after the Bureau was abolished, MAS was transferred to the USGS. The two data bases were compiled for different purposes and contain very different mformation. For instance, MAS contains information on costs, details of mining methods, and feasibility studies. MRDS has mineralogical and geologic data that are not contained in MAS. Because they are both mineral-resource data bases, however, they contain some information in common, such as location, name(s) of sites, and commodities present. Both data bases are international in scope, and both are quite large. MRDS contains over 110,000 records, while MAS has over 220,000. One reason that MAS has more records is that it contains information on smelters, mill sites, and fossil fuel sites, as well as mineral- resource sites. The USGS is working to combine the information in both data bases. This is a large undertaking that will require some years to complete. In the interim, information from both data bases will still be available

  9. Home-based Healthcare Technology

    DEFF Research Database (Denmark)

    Verdezoto, Nervo

    Sustaining daily, unsupervised healthcare activities in non-clinical settings such as the private home can challenge, among others, older adults. To support such unsupervised care activities, an increasingly number of reminders and monitoring systems are being designed. However, most...... of these systems target a specific treatment or condition and might not be sufficient to support the care management work at home. Based on a case study approach, my research investigates home-based healthcare practices and how they can inform future design of home-based healthcare technology that better account...... for the home setting and people’s everyday activities....

  10. Office-based laryngeal injections.

    Science.gov (United States)

    Mallur, Pavan S; Rosen, Clark A

    2013-02-01

    Office-based vocal fold injection (VFI), though initially described more than a century ago, has recently reemerged as an attractive alternative to VFI performed during microsuspension laryngoscopy. Multiple office-based approaches exist, including percutaneous, peroral, and transnasal endoscopic approaches. Surgeon preference typically dictates the approach, although patient tolerance or anatomic variations are also key factors. Regardless of the approach or indication, a myriad of technical considerations make preparation and familiarity requisite for optimal patient outcomes. Office-based VFI offers several distinct advantages over traditional direct or microsuspension laryngoscopy VFI, making it a standard of treatment for a variety of indications. PMID:23177408

  11. Graph Model Based Indoor Tracking

    DEFF Research Database (Denmark)

    Jensen, Christian Søndergaard; Lu, Hua; Yang, Bin

    2009-01-01

    infrastructure for different symbolic positioning technologies, e.g., Bluetooth and RFID. More specifically, the paper proposes a model of indoor space that comprises a base graph and mappings that represent the topology of indoor space at different levels. The resulting model can be used for one or several...... indoor positioning technologies. Focusing on RFID-based positioning, an RFID specific reader deployment graph model is built from the base graph model. This model is then used in several algorithms for constructing and refining trajectories from raw RFID readings. Empirical studies with implementations...

  12. Formal Component-Based Semantics

    CERN Document Server

    Madlener, Ken; van Eekelen, Marko; 10.4204/EPTCS.62.2

    2011-01-01

    One of the proposed solutions for improving the scalability of semantics of programming languages is Component-Based Semantics, introduced by Peter D. Mosses. It is expected that this framework can also be used effectively for modular meta theoretic reasoning. This paper presents a formalization of Component-Based Semantics in the theorem prover Coq. It is based on Modular SOS, a variant of SOS, and makes essential use of dependent types, while profiting from type classes. This formalization constitutes a contribution towards modular meta theoretic formalizations in theorem provers. As a small example, a modular proof of determinism of a mini-language is developed.

  13. PBW bases and KLR algebras

    OpenAIRE

    Kato, Syu

    2012-01-01

    We generalize Lusztig's geometric construction of the PBW bases of finite quantum groups of type $\\mathsf{ADE}$ under the framework of [Varagnolo-Vasserot, J. reine angew. Math. 659 (2011)]. In particular, every PBW basis of such quantum groups is proven to yield a semi-orthogonal collection in the module category of the KLR-algebras. This enables us to prove Lusztig's conjecture on the positivity of the canonical (lower global) bases in terms of the (lower) PBW bases in the $\\mathsf{ADE}$ ca...

  14. Export base of czech regions

    OpenAIRE

    Michal Šulc

    2010-01-01

    This article deals with the analysis of structure and size of goods exported from the Czech regions in the period of 2003–2009. The analysis is related to the export base theory. At first there is the export base theory characterised in the beginning of the article. There is a limited data base for the assessing of international flow of goods and services in case of Czech regions, for only the data of exported goods is regionally monitored. Both the presence and the increase of importance of ...

  15. Solar based hydrogen production systems

    CERN Document Server

    Dincer, Ibrahim

    2013-01-01

    This book provides a comprehensive analysis of various solar based hydrogen production systems. The book covers first-law (energy based) and second-law (exergy based) efficiencies and provides a comprehensive understanding of their implications. It will help minimize the widespread misuse of efficiencies among students and researchers in energy field by using an intuitive and unified approach for defining efficiencies. The book gives a clear understanding of the sustainability and environmental impact analysis of the above systems. The book will be particularly useful for a clear understanding

  16. Seeing graphene-based sheets

    Directory of Open Access Journals (Sweden)

    Jaemyung Kim

    2010-03-01

    Full Text Available Graphene-based sheets such as graphene, graphene oxide and reduced graphene oxide have stimulated great interest due to their promising electronic, mechanical and thermal properties. Microscopy imaging is indispensable for characterizing these single atomic layers, and oftentimes is the first measure of sample quality. This review provides an overview of current imaging techniques for graphene-based sheets and highlights a recently developed fluorescence quenching microscopy technique that allows high-throughput, high-contrast imaging of graphene-based sheets on arbitrary substrate and even in solution.

  17. Flow tracing based on current

    Institute of Scientific and Technical Information of China (English)

    蔡兴国; 曹海龙

    2001-01-01

    Analyses the flow tracing based on power flow, points out that the detachment of reactive power and active power is unrealiable and concludes that the current is the real basic of flow tracing,and proposes the new flow tracing model based on current, which devides the current into active current and reactive current, analyses the theory about the matrix to deal with the precision and realization of the flow tracing, and then proposes a new pricing model by fixed rate and marginal rate, which keeps not only economy information such as congestion cost in marginal cost based pricing, but also benefits to make both ends meet.

  18. Consumption-based Equity Valuation

    DEFF Research Database (Denmark)

    Bach, Christian; Christensen, Peter Ove

    2013-01-01

    model performs substantially better than the best performing standard valuation model when comparing absolute valuation errors. Both types of models are able to identify investment strategies with subsequent excess returns but also in this setting, the CCAPM-based valuation model outperforms...... residual income for risk in the numerator rather than through a risk-adjusted cost of equity in the denominator. The risk-adjustments are derived based on assumptions about the time-series properties of residual income returns and aggregate consumption rather than on historical stock returns. We compare...... the performance of the model with several implementations of standard valuation models, both in terms of absolute valuation errors, and in terms of the returns on simple investment strategies based on the differences between model and market prices in the respective valuation models. The CCAPM-based valuation...

  19. Team-based global organizations

    DEFF Research Database (Denmark)

    Zander, Lena; Butler, Christina; Mockaitis, Audra;

    2015-01-01

    characterized by decreased importance of hierarchal structures, more fluidity across borders, even a possible dissolution of firm boundaries, we move towards team-based organizing as an alternative to more traditional forms of hierarchical-based organizing in global firms. To provide input for a discussion...... of challenges and opportunities of future global organizing as being team-based, we presented new advancements in the study of global teams, leadership, process and outcomes divided into four themes. Two specifically address processes in global teams: 1) the benefits of openness towards linguistic and value...... diversity in enhancing team creativity and performance, and 2) the sharing of knowledge in team-based organizations, while the other two themes address global team leadership: 3) the unprecedented significance of social capital for the success of global team leader roles; and 4) the link between shared...

  20. FEMA DFIRM Base Flood Elevations

    Data.gov (United States)

    Minnesota Department of Natural Resources — The Base Flood Elevation (BFE) table is required for any digital data where BFE lines will be shown on the corresponding Flood Insurance Rate Map (FIRM). Normally,...

  1. Mindfulness-Based Stress Reduction

    Science.gov (United States)

    ... R S T U V W X Y Z Mindfulness-Based Stress Reduction (MBSR) Information 5 Things You ... Better Than Usual Care Alone (03/22/16) Mindfulness Meditation May Benefit People With Chronic Insomnia (09/ ...

  2. Industry Based Survey (IBS) Cod

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The "Gulf of Maine Atlantic Cod Industry-Based Survey" was a collaboration of the Massachusetts Division of Marine Fisheries and the fishing industry, with support...

  3. Studying Sensing-Based Systems

    DEFF Research Database (Denmark)

    Kjærgaard, Mikkel Baun

    2013-01-01

    Recent sensing-based systems involve a multitude of users, devices, and places. These types of systems challenge existing approaches for conducting valid system evaluations. Here, the author discusses such evaluation challenges and revisits existing system evaluation methodologies....

  4. Base Flood Elevation (BFE) Lines

    Data.gov (United States)

    Department of Homeland Security — The Base Flood Elevation (BFE) table is required for any digital data where BFE lines will be shown on the corresponding Flood Insurance Rate Map (FIRM). Normally...

  5. The Knowledge Based Information Economy

    OpenAIRE

    Eliasson, Gunnar; Fölster, Stefan; Lindberg, Thomas; Pousette, Tomas; Erol TAYMAZ

    1990-01-01

    Working Paper No. 256 is published as "The Knowledge Based Information Economy" (authors: Gunnar Eliasson, Stefan Fölster, Thomas Lindberg, Tomas Pousette and Erol Taymaz). Stockholm: Industrial Institute for Economic and Social Research and Telecon, 1990.

  6. Base Flow Model Validation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The program focuses on turbulence modeling enhancements for predicting high-speed rocket base flows. A key component of the effort is the collection of...

  7. Evidence-based playground design

    DEFF Research Database (Denmark)

    Refshauge, Anne Dahl; Stigsdotter, Ulrika K.; Lamm, Bettina;

    2015-01-01

    This paper develops, explores and evaluates an evidence-based approach to playground design, with a public park playground (playlab Cph) in Copenhagen as a case study. In the increasingly urbanised world, park playgrounds are valuable places that support healthy child development by providing...... opportunities for play, nature exploration and sensory stimulation. As it is increasingly expected that designers base their decisions on research evidence, there is a need to develop approaches to facilitate this, which also applies to playground design. The design of PlayLab Cph was based on relevant evidence......, best practice, and the theories of Affordances and Behaviour Settings. A post-occupancy evaluation was carried out through a questionnaire survey and observation studies, which revealed that a majority of the potential evidence-based affordances were actualised, and that the application of the theories...

  8. Oil-based paint poisoning

    Science.gov (United States)

    Paint - oil based - poisoning ... Hydrocarbons are the primary poisonous ingredient in oil paints. Some oil paints have heavy metals such as lead, mercury, cobalt, and barium added as pigment. These heavy metals can cause additional ...

  9. Industry Based Survey (IBS) Yellowtail

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The "Southern New England Yellowtail Flounder Industry-Based Survey" was a collaboration between the Rhode Island Division of Fish and Wildlife and the fishing...

  10. Consent Based Verification System (CBSV)

    Data.gov (United States)

    Social Security Administration — CBSV is a fee-based service offered by SSA's Business Services Online (BSO). It is used by private companies to verify the SSNs of their customers and clients that...

  11. Content Based Video Retrieval Systems

    Directory of Open Access Journals (Sweden)

    B V Patel

    2012-05-01

    Full Text Available With the development of multimedia data types and available bandwidth there is huge demand of video retrieval systems, as users shift from text based retrieval systems to content based retrieval systems. Selection of extracted features play an important role in content based video retrieval regardless of video attributes being under consideration. These features are intended for selecting, indexing and ranking according to their potential interest to the user. Good features selection also allows the time and space costs of the retrieval process to be reduced. This survey reviews the interesting features that can beextracted from video data for indexing and retrieval along with similarity measurement methods. We also identify present research issues in area of content based video retrieval systems.

  12. US Air Force Base Observations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hourly observations taken by U.S. Air Force personnel at bases in the United States and around the world. Foreign observations concentrated in the Middle East and...

  13. Random Decrement Based FRF Estimation

    DEFF Research Database (Denmark)

    Brincker, Rune; Asmussen, J. C.

    The problem of estimating frequency response functions and extracting modal parameters is the topic of this paper. A new method based on the Random Decrement technique combined with Fourier transformation and the traditional pure Fourier transformation based approach is compared with regard to...... speed and quality. The basis of the new method is the Fourier transformation of the Random Decrement functions which can be used to estimate the frequency response functions. The investigations are based on load and response measurements of a laboratory model of a 3 span bridge. By applying both methods...... to these measurements the estimation time of the frequency response functions can be compared. The modal parameters estimated by the methods are compared. It is expected that the Random Decrement technique is faster than the traditional method based on pure Fourier Transformations. This is due to the...

  14. Random Decrement Based FRF Estimation

    DEFF Research Database (Denmark)

    Brincker, Rune; Asmussen, J. C.

    1997-01-01

    The problem of estimating frequency response functions and extracting modal parameters is the topic of this paper. A new method based on the Random Decrement technique combined with Fourier transformation and the traditional pure Fourier transformation based approach is compared with regard to...... speed and quality. The basis of the new method is the Fourier transformation of the Random Decrement functions which can be used to estimate the frequency response functions. The investigations are based on load and response measurements of a laboratory model of a 3 span bridge. By applying both methods...... to these measurements the estimation time of the frequency response functions can be compared. The modal parameters estimated by the methods are compared. It is expected that the Random Decrement technique is faster than the traditional method based on pure Fourier Transformations. This is due to the...

  15. Chip-based droplet sorting

    Energy Technology Data Exchange (ETDEWEB)

    Beer, Neil Reginald; Lee, Abraham; Hatch, Andrew

    2014-07-01

    A non-contact system for sorting monodisperse water-in-oil emulsion droplets in a microfluidic device based on the droplet's contents and their interaction with an applied electromagnetic field or by identification and sorting.

  16. Chip-based droplet sorting

    Science.gov (United States)

    Beer, Neil Reginald; Lee, Abraham; Hatch, Andrew

    2014-07-01

    A non-contact system for sorting monodisperse water-in-oil emulsion droplets in a microfluidic device based on the droplet's contents and their interaction with an applied electromagnetic field or by identification and sorting.

  17. Kernel model-based diagnosis

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The methods for computing the kemel consistency-based diagnoses and the kernel abductive diagnoses are only suited for the situation where part of the fault behavioral modes of the components are known. The characterization of the kernel model-based diagnosis based on the general causal theory is proposed, which can break through the limitation of the above methods when all behavioral modes of each component are known. Using this method, when observation subsets deduced logically are respectively assigned to the empty or the whole observation set, the kernel consistency-based diagnoses and the kernel abductive diagnoses can deal with all situations. The direct relationship between this diagnostic procedure and the prime implicants/implicates is proved, thus linking theoretical result with implementation.

  18. Hospital Value-Based Purchasing

    Data.gov (United States)

    U.S. Department of Health & Human Services — Hospital Value-Based Purchasing (VBP) is part of the Centers for Medicare and Medicaid Services (CMS) long-standing effort to link Medicares payment system to a...

  19. Cage-based performance capture

    CERN Document Server

    Savoye, Yann

    2014-01-01

    Nowadays, highly-detailed animations of live-actor performances are increasingly easier to acquire and 3D Video has reached considerable attentions in visual media production. In this book, we address the problem of extracting or acquiring and then reusing non-rigid parametrization for video-based animations. At first sight, a crucial challenge is to reproduce plausible boneless deformations while preserving global and local captured properties of dynamic surfaces with a limited number of controllable, flexible and reusable parameters. To solve this challenge, we directly rely on a skin-detached dimension reduction thanks to the well-known cage-based paradigm. First, we achieve Scalable Inverse Cage-based Modeling by transposing the inverse kinematics paradigm on surfaces. Thus, we introduce a cage inversion process with user-specified screen-space constraints. Secondly, we convert non-rigid animated surfaces into a sequence of optimal cage parameters via Cage-based Animation Conversion. Building upon this re...

  20. 一种基于薄膜太阳能电池的野战多功能应急电源的研制%Development of Field Multifunctional Emergency Power System Based on Film Solar Cell

    Institute of Scientific and Technical Information of China (English)

    胡军智; 徐新民; 杜生明; 许健; 徐海琴; 张坤; 曹铁军; 殷朝庆

    2012-01-01

    目的:研制一种在野外没有市电或发电机的恶劣环境下,能够正常使用的光伏型野战多功能应急电源.方法:将多张铜铟镓铟(CIGS)薄膜太阳能电池片镶嵌在基布上,制作成柔软的“太阳能电池布”,使用时,展开与控制电源箱相连并为其供电;不用时,折叠包装好放入电源控制箱内.整个电源以太阳能光伏输入为主,以市电、发电机等为辅,经过DC/AC、DC/DC、AC/DC等各种变换及控制后,为混合超级电容电池充电储能,最后输出直流电源和交流电源.结果:通过野外测试,该电源采用多种形式输入,输出直流多样、交流稳定,功能多,负载范围大,质量小,组合简单.结论:该新型电源解决了部队在野外紧急情况下因无电源而造成的诸多难题,且便于战时野外携行,将较大程度地提高野战后勤保障能力.%Objective To develop a photovoltaic field multifunctional emergency power system for the environment without electric supply. Methods Solar cell fabric was formed by several CIGS film solar cell gets inlayed onto the fabric, which was connected with the control power box while in use and packed into the box when idle. Besides solar photovoltaic; energy, the source also included electric source and generator. Through current transformation and control of DC/AC, DC/DC and AC/ DC, the hybrid super-capacitor batteries were charged to output direct current and alternating current. Results Field tests proved lhat the emergency power system, with multi kinds of input and output, was stable, multifunctional, light and casy-to-assemble. Conclusion The field multifunctional emergency power system could avail field logistic support. [Chinese Medical Equipment Journal,2012,33(7) :21-22,46

  1. Detector Based Radio Tomographic Imaging

    OpenAIRE

    Yiğitler, Hüseyin; Jäntti, Riku; Kaltiokallio, Ossi; Patwari, Neal

    2016-01-01

    Received signal strength based radio tomographic imaging is a popular device-free indoor localization method which reconstructs the spatial loss field of the environment using measurements from a dense wireless network. Existing methods solve an associated inverse problem using algebraic or compressed sensing reconstruction algorithms. We propose an alternative imaging method that reconstructs spatial field of occupancy using a back-projection based reconstruction algorithm. The introduced sy...

  2. Donor Schiff Base Polymeric Complexes

    Directory of Open Access Journals (Sweden)

    Shubhangi N. Kotkar

    2013-01-01

    Full Text Available A series of new polymeric complexes of Mn(II, Co(II, Ni(II, Cu(II, and Zn(II were prepared with a Schiff base ligand derived from condensation of 2,4-dihydroxy acetophenone and p-phenylene diamine and characterized by elemental analysis and IR and NMR spectral data. The antimicrobial activity of the Schiff base and its polymeric complexes have been studied.

  3. Lazy Transformation-Based Learning

    OpenAIRE

    Samuel, Ken

    1998-01-01

    We introduce a significant improvement for a relatively new machine learning method called Transformation-Based Learning. By applying a Monte Carlo strategy to randomly sample from the space of rules, rather than exhaustively analyzing all possible rules, we drastically reduce the memory and time costs of the algorithm, without compromising accuracy on unseen data. This enables Transformation- Based Learning to apply to a wider range of domains, as it can effectively consider a larger number ...

  4. Leather inspection based on wavelets

    OpenAIRE

    Sobral, João Luís Ferreira

    2005-01-01

    This paper presents a new methodology to detect leather defects, based on the wavelet transform. The methodology uses a bank of optimised filters, where each filter is tuned to one defect type. Filter shape and wavelet sub-band are selected based the maximisation of the ratio between features values on defect regions and on normal regions. The proposed methodology can detect defects even when small features variations are present, which are not detect by generic texture classification techniq...

  5. Formalization in Component Based Development

    DEFF Research Database (Denmark)

    Holmegaard, Jens Peter; Knudsen, John; Makowski, Piotr;

    2006-01-01

    We present a unifying conceptual framework for components, component interfaces, contracts and composition of components by focusing on the collection of properties or qualities that they must share. A specific property, such as signature, functionality behaviour or timing is an aspect. Each aspe...... by small examples, using UML as concrete syntax for various aspects, and is illustrated by one larger case study based on an industrial prototype of a complex component based system....

  6. Identity Based Color Image Cryptography

    OpenAIRE

    Gopi Krishnan S; Loganathan D

    2011-01-01

    An Identity based cryptography based on visual cryptography scheme was proposed for protecting color image. A color image to be protected and authentic entities such as account number, password, signature image are given as input. The binary key image is obtained by distributing the digital signature of obtained authentic entities. A secret color image which needs to be communicated is decomposed into three grayscale tones of Y-Cb-Cr color component. Then these grayscale images are half-toned...

  7. Seeing graphene-based sheets

    OpenAIRE

    Jaemyung Kim; Franklin Kim; Jiaxing Huang

    2010-01-01

    Graphene-based sheets such as graphene, graphene oxide and reduced graphene oxide have stimulated great interest due to their promising electronic, mechanical and thermal properties. Microscopy imaging is indispensable for characterizing these single atomic layers, and oftentimes is the first measure of sample quality. This review provides an overview of current imaging techniques for graphene-based sheets and highlights a recently developed fluorescence quenching microscopy technique that al...

  8. Fuzzy Bases of Fuzzy Domains

    OpenAIRE

    Sanping Rao; Qingguo Li

    2013-01-01

    This paper is an attempt to develop quantitative domain theory over frames. Firstly, we propose the notion of a fuzzy basis, and several equivalent characterizations of fuzzy bases are obtained. Furthermore, the concept of a fuzzy algebraic domain is introduced, and a relationship between fuzzy algebraic domains and fuzzy domains is discussed from the viewpoint of fuzzy basis. We finally give an application of fuzzy bases, where the image of a fuzzy domain can be preserved under some special ...

  9. Brain plasticity-based therapeutics

    OpenAIRE

    Merzenich, Michael M.; Van Vleet, Thomas M.; Nahum, Mor

    2014-01-01

    The primary objective of this review article is to summarize how the neuroscience of brain plasticity, exploiting new findings in fundamental, integrative and cognitive neuroscience, is changing the therapeutic landscape for professional communities addressing brain-based disorders and disease. After considering the neurological bases of training-driven neuroplasticity, we shall describe how this neuroscience-guided perspective distinguishes this new approach from (a) the more-behavioral, tra...

  10. Brain Plasticity-Based Therapeutics

    OpenAIRE

    Michael eMerzenich; Mor eNahum; Tom eVan Vleet

    2014-01-01

    The primary objective of this review article is to summarize how the neuroscience of brain plasticity, exploiting new findings in fundamental, integrative and cognitive neuroscience, is changing the therapeutic landscape for professional communities addressing brain-based disorders and disease. After considering the neurological bases of training-driven neuroplasticity, we shall describe how this neuroscience-guided perspective distinguishes this new approach from a) the more-behavioral, trad...

  11. Dimensions of problem based learning

    DEFF Research Database (Denmark)

    Nielsen, Jørgen Lerche; Andreasen, Lars Birch

    2013-01-01

    The article contributes to the literature on problem based learning and problem-oriented project work, building on and reflecting the experiences of the authors through decades of work with problem-oriented project pedagogy. The article explores different dimensions of problem based learning...... and Learning (MIL). We discuss changes in the roles of the teachers as supervisors within this learning environment, and we explore the involvement of students as active participants and co-designers of how course and project activities unfold....

  12. Knowledge-based Telecom Industry

    OpenAIRE

    Vinje, Villeman; Nordkvelde, Marius

    2011-01-01

    BI Norwegian School of Management is conducting a national research project entitled “A knowledge-based Norway”. Thirteen major knowledge-based industries in Norway are being analyzed under the auspices of the project. This study assesses the underlying properties of a global knowledge hub to examine the extent to which the Norwegian telecom industry – which encompasses all telecom firms located in Norway regardless of ownership – constitutes a global knowledge hub. It commences with a ge...

  13. Knowledge Management Based on ERP

    OpenAIRE

    Qian Feng; Yuanyuan Huang

    2009-01-01

    In an information explosive era, knowledge management has become a hot field in enterprise informatization. In order to adapt to the competitive environment, it is now an urgent task to add knowledge management to ERP system and integrate learning and innovation on the platform of enterprise information system based on ERP. This paper focuses on knowledge management based on ERP and introduces a knowledge management system: KRM.

  14. Uranium-Based Cermet Alloys

    International Nuclear Information System (INIS)

    The paper describes certain features of dispersion-hardened uranium-based cermets. As possible hardening materials, consideration was given to UO2, UC, Al2O3, MgO and UBe13. Data were obtained on the behaviour of uranium alloys containing the above-mentioned admixtures during creep tests, short-term strength tests and cyclic thermal treatment. The corrosion resistance o f UBe13-based uranium alloys was also studied. )author)

  15. Template-Based Active Contours

    OpenAIRE

    Mogali, Jayanth Krishna; Pediredla, Adithya Kumar; Seelamantula, Chandra Sekhar

    2013-01-01

    We develop a generalized active contour formalism for image segmentation based on shape templates. The shape template is subjected to a restricted affine transformation (RAT) in order to segment the object of interest. RAT allows for translation, rotation, and scaling, which give a total of five degrees of freedom. The proposed active contour comprises an inner and outer contour pair, which are closed and concentric. The active contour energy is a contrast function defined based on the intens...

  16. Method for gesture based modeling

    DEFF Research Database (Denmark)

    2006-01-01

    A computer program based method is described for creating models using gestures. On an input device, such as an electronic whiteboard, a user draws a gesture which is recognized by a computer program and interpreted relative to a predetermined meta-model. Based on the interpretation, an algorithm...... is assigned to the gesture drawn by the user. The executed algorithm may, for example, consist in creating a new model element, modifying an existing model element, or deleting an existing model element....

  17. CORBA Based CIMS Application Integration

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Common object request broker architecture (CORBA) provides the framework and the mechanism for distributed object operation. It can also be applied to computer integrated manufacturing system (CIMS) application integration. This paper studies the CIMS information service requirement, presents a CORBA based integration approach including the CORBA based CIM information system architecture and the application integration mechanism, and discusses the relationship between CORBA and the CIM application integration platform.

  18. Ridge-based fingerprint matching

    OpenAIRE

    Pohar, Jaka

    2013-01-01

    The diploma thesis presents an upgrade of the FingerIdent fingerprint verification system. The current version of the system uses a minutia matching procedure for comparison of two fingerprints. In order to improve the security of the system we have implemented an additional matching procedure which is based on the use of fingerprint ridges. Algorithm inputs are lists of ridge points of two fingerprints. At the beginning the algorithm searches the initial base ridge pair and matches it. Th...

  19. Base isolation of fluid containers

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S. [Cygna Group Inc./ICF Kaiser International, Oakland, CA (United States)

    1995-12-01

    Fluid containers often constitute critical internal equipment in power plants. However, due to possible structure-equipment interaction effect they are particularly vulnerable during strong earthquake events. An effective technique for protecting fluid containers is base isolation. By deflecting the possible seismic input energy into the superstructure, base isolation can substantially reduce seismic demand on the containers, making it more cost effective than equivalent conventional design.

  20. A hybrid base isolation system

    Energy Technology Data Exchange (ETDEWEB)

    Hart, G.C. [Univ. of California, Los Angeles, CA (United States); Lobo, R.F.; Srinivasan, M. [Hart Consultant Group, Santa Monica, CA (United States); Asher, J.W. [kpff Engineers, Santa Monica, CA (United States)

    1995-12-01

    This paper proposes a new analysis procedure for hybrid base isolation buildings when considering the displacement response of a base isolated building to wind loads. The system is considered hybrid because of the presence of viscous dampers in the building above the isolator level. The proposed analysis approach incorporates a detailed site specific wind study combined with a dynamic nonlinear analysis of the building response.