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Sample records for superior electrical performance

  1. The Business Value of Superior Energy Performance

    Energy Technology Data Exchange (ETDEWEB)

    McKane, Aimee; Scheihing, Paul; Evans, Tracy; Glatt, Sandy; Meffert, William

    2015-08-04

    Industrial facilities participating in the U.S. Department of Energy’s (US DOE) Superior Energy Performance (SEP) program are finding that it provides them with significant business value. This value starts with the implementation of ISO 50001-Energy management system standard, which provides an internationally-relevant framework for integration of energy management into an organization’s business processes. The resulting structure emphasizes effective use of available data and supports continual improvement of energy performance. International relevance is particularly important for companies with a global presence or trading interests, providing them with access to supporting ISO standards and a growing body of certified companies representing the collective knowledge of communities of practice. This paper examines the business value of SEP, a voluntary program that builds on ISO 50001, inviting industry to demonstrate an even greater commitment through third-party verification of energy performance improvement to a specified level of achievement. Information from 28 facilities that have already achieved SEP certification will illustrate key findings concerning both the value and the challenges from SEP/ISO 50001 implementation. These include the facilities’ experience with implementation, internal and external value of third-party verification of energy performance improvement; attractive payback periods and the importance of SEP tools and guidance. US DOE is working to bring the program to scale, including the Enterprise-Wide Accelerator (SEP for multiple facilities in a company), the Ratepayer-Funded Program Accelerator (supporting tools for utilities and program administrators to include SEP in their program offerings), and expansion of the program to other sectors and industry supply chains.

  2. Sinus node, phrenic nerve and electrical connections between superior vena cava and right atrium: lessons learned from a prospective study

    Institute of Scientific and Technical Information of China (English)

    LONG De-yong; MA Chang-sheng; JIANG Hong; DONG Jian-zeng; LIU Xing-peng; HUANG He; TANG Yan-hong; WU Gang; HUANG Cong-xin

    2009-01-01

    Background When performing superior vena cava isolation, the major concerns are inadvertent ablation on sinus node and right phrenic nerve. However, little is known about the spatial relationship of electrical connections between superior vena cava and right atrium with the sinus node and phrenic nerve locations among individual patients.Methods We studied 87 patients (male/female 60/27, mean age of (51±9) years) with atrial fibrillation. Before superior vena cava isolation, the sinus node site was defined by right atrium activation mapping during sinus rhythm and the right phrenic nerve site was localized via pacing manoeuvre. Superior vena cava was isolated by ablation at the electrical connection under the guidance of circular mapping catheter. The sites of sinus node, phrenic nerve and electrical connections were noted. Continuous variables were compared using Student's t test. A P value <0.05 was considered statistically significant.Results Right atrium activation mapping revealed that the sinus node located at the anterior lateral segment of superior vena cava-right atrium junction in all patients, in 82 patients with detectable diaphragmatic stimulations, the phrenic nerve sites were predominantly at the lateral segment (70/82) with anterior lateral and anterior segments for a few patients. A total of 165 electrical connections were located among all 87 patients, and this averaged 1.8±0.6 (1-3) per patient. The anterior septum (72 patients (43.6%)), the anterior wall (40 (24.2%)), and the posterior septum (35 (35.4%)) of superior vena cava-right atrium junction were the electrical connection regular sites. Superior vena cava was isolated in all patients. Two patients developed sinus bradycardia, with 3 mild superior vena cava stenosis and 2 phrenic nerve palsy.Conclusions The sinus node, phrenic nerve and electrical connection sites were distributed along the superior vena cava-right atrium junctions at expected locations for most patients. The electrical

  3. Unique properties of halide perovskites as possible origins of the superior solar cell performance.

    Science.gov (United States)

    Yin, Wan-Jian; Shi, Tingting; Yan, Yanfa

    2014-07-16

    Halide perovskites solar cells have the potential to exhibit higher energy conversion efficiencies with ultrathin films than conventional thin-film solar cells based on CdTe, CuInSe2 , and Cu2 ZnSnSe4 . The superior solar-cell performance of halide perovskites may originate from its high optical absorption, comparable electron and hole effective mass, and electrically clean defect properties, including point defects and grain boundaries.

  4. Electrodeposition of Gold on Lignocelluloses and Graphite-Based Composite Paper Electrodes for Superior Electrical Properties

    Science.gov (United States)

    Sultana, Ishrat; Razaq, Aamir; Idrees, M.; Asif, M. H.; Ali, Hassan; Arshad, Asim; Iqbal, Shahid; Ramay, Shahid M.; Hussain, Shahzada Qamar

    2016-10-01

    Graphite-based composites are commonly used as an anode and current collector for energy storage devices; however, they have inherently limited potential for large scale rechargeable systems due to a brittle structure. In this study, flexible and light-weight graphite-based electrodes are prepared by incorporation of lignocelluloses fibers directly collected from a self-growing plant, Typha Angistifolia. Electrical properties of graphite and lignocelluloses composite sheets are enhanced by electrodeposition of gold in a three-electrode setup. Electrochemical deposition of gold on a lignocelluloses/graphite paper electrode was obtained in potentiostatic mode by the application of reduction potential -0.95 V for 2000 s, 600 s, and 100 s. The gold-deposited paper electrodes showed efficient kinetics by shifting redox peaks towards lower potentials in cyclic voltammetry measurements, whereas impedance measurements revealed seven orders of magnitude reduction in the resistive properties. Incorporated flexibility and superior electrical/electrochemical performance within presented graphite-based composites will provide cutting-edge characteristics for high-tech application of energy storage devices by keeping a focus on modern disposable technology.

  5. Biological Motion Task Performance Predicts Superior Temporal Sulcus Activity

    Science.gov (United States)

    Herrington, John D.; Nymberg, Charlotte; Schultz, Robert T.

    2011-01-01

    Numerous studies implicate superior temporal sulcus (STS) in the perception of human movement. More recent theories hold that STS is also involved in the "understanding" of human movement. However, almost no studies to date have associated STS function with observable variability in action understanding. The present study directly associated STS…

  6. Electrical actuators applications and performance

    CERN Document Server

    De Fornel, Bernard

    2013-01-01

    This helpful resource covers a large range of information regarding electrical actuators. In particular, robustness, a very problematic issue, is fully explored in a dedicated chapter. The text also deals with he estimate of non-measurable mechanical variables by examining the estimate of load moment, then observation of the positioning of a command without mechanical sensor. Finally, it examines the conditions needed to measure variables and real implementation of numerical algorithms. This is a key working resource for electrical engineers.

  7. Advanced Modeling of Teaming Data to Enable Superior Team Performance

    Science.gov (United States)

    2014-11-04

    permission should be directed to the Software Engineering Institute at permission@sei.cmu.edu. CMMI ® is registered in the U.S. Patent and Trademark...Hill AFB) has had a long-term initiative to improve performance based on CMMI  and TSP. Work Progress • Multi-year effort with SEI support and...internal resource commitments • Training in the basic SEI technologies plus extensive training in six-sigma methods . Plan: sustain and improve Goal

  8. Substitutional Doping for Aluminosilicate Mineral and Superior Water Splitting Performance

    Science.gov (United States)

    Zhang, Yi; Fu, Liangjie; Shu, Zhan; Yang, Huaming; Tang, Aidong; Jiang, Tao

    2017-07-01

    Substitutional doping is a strategy in which atomic impurities are optionally added to a host material to promote its properties, while the geometric and electronic structure evolution of natural nanoclay mineral upon substitutional metal doping is still ambiguous. This paper first designed an efficient lanthanum (La) doping strategy for nanotubular clay (halloysite nanotube, HNT) through the dynamic equilibrium of a substitutional atom in the presence of saturated AlCl3 solution, and systematic characterization of the samples was performed. Further density functional theory (DFT) calculations were carried out to reveal the geometric and electronic structure evolution upon metal doping, as well as to verify the atom-level effect of the La doping. The CdS loading and its corresponding water splitting performance could demonstrate the effect of La doping. CdS nanoparticles (11 wt.%) were uniformly deposited on the surface of La-doped halloysite nanotube (La-HNT) with the average size of 5 nm, and the notable photocatalytic hydrogen evolution rate of CdS/La-HNT reached up to 47.5 μmol/h. The results could provide a new strategy for metal ion doping and constructive insight into the substitutional doping mechanism.

  9. Intangible Assets and Superior and Sustained Performance of Innovative Brazilian Firms

    Directory of Open Access Journals (Sweden)

    Márcia Martins Mendes De Luca

    2014-10-01

    Full Text Available According to the Resource-Based View, the nature of the resources, competences and knowledge accumulated by firms are the major causes of variation in business performance. In view of the importance attributed to intangible assets, the purpose of the present study was to investigate whether innovative firms with superior and sustained performance and firms without superior and sustained performance differ with regard to investments in intangible assets. The sample consisted of 137 firms listed on the Brazilian stock exchange from 2007 to 2010 and belonging to innovative sectors according to the Brazilian Innovation Index. Only 51 firms with profitability above the sector average during the entire study period (four years met the criterion of superior and sustained performance. Thus, using return on assets as a proxy for performance, investments in intangibles were found to be greater in firms without superior and sustained performance, particularly with regard to the categories intellectual property assets (the predominant category and infrastructure assets. Based on the lack of evidence for a significant correlation between corporate performance and investment in intangible assets, our initial hypothesis that a positive relation exists between the composition of investments in intangible assets and the performance of innovative firms could not be confirmed.

  10. Competitively Distinct Operations as a Key for Superior and Sustainable Business Performance: An Example from Walmart

    Directory of Open Access Journals (Sweden)

    Binod Timilsina

    2015-09-01

    Full Text Available Existing research on the resource-based view (RBV has provided limited evidence on how firms achieve superior and sustainable business performance; this failure is because current literature de-emphasizes the importance of operations. This paper argues that to gain and sustain superior business performance, a firm’s sustainable competitive advantage is not enough, its operations also needs to be competitively distinct. Therefore, through unifying the necessary conditions of superior and sustainable business performance the paper presents a better understanding of the RBV. The success story of Walmart, from existing literature, is considered as an example to support the proposed framework. The paper concludes that the cost of operations, opportunity cost, cost of resources and possible output are the crucial factors in resource choice and operations decision to secure competitively distinct operations. Finally, theoretical and managerial implications, research limitations and future research possibilities are discussed.

  11. Superior Electrical Conductivity in Hydrogenated Layered Ternary Chalcogenide Nanosheets for Flexible All-Solid-State Supercapacitors.

    Science.gov (United States)

    Hu, Xin; Shao, Wei; Hang, Xudong; Zhang, Xiaodong; Zhu, Wenguang; Xie, Yi

    2016-05-04

    As the properties of ultrathin two-dimensional (2D) crystals are strongly related to their electronic structures, more and more attempts were carried out to tune their electronic structures to meet the high standards for the construction of next-generation smart electronics. Herein, for the first time, we show that the conductive nature of layered ternary chalcogenide with formula of Cu2 WS4 can be switched from semiconducting to metallic by hydrogen incorporation, accompanied by a high increase in electrical conductivity. In detail, the room-temperature electrical conductivity of hydrogenated-Cu2 WS4 nanosheet film was almost 10(10) times higher than that of pristine bulk sample with a value of about 2.9×10(4)  S m(-1) , which is among the best values for conductive 2D nanosheets. In addition, the metallicity in the hydrogenated-Cu2 WS4 is robust and can be retained under high-temperature treatment. The fabricated all-solid-state flexible supercapacitor based on the hydrogenated-Cu2 WS4 nanosheet film shows promising electrochemical performances with capacitance of 583.3 F cm(-3) at a current density of 0.31 A cm(-3) . This work not only offers a prototype material for the study of electronic structure regulation in 2D crystals, but also paves the way in searching for highly conductive electrodes.

  12. High concentration nitrogen doped carbon nanotube anodes with superior Li+ storage performance for lithium rechargeable battery application

    Science.gov (United States)

    Li, Xifei; Liu, Jian; Zhang, Yong; Li, Yongliang; Liu, Hao; Meng, Xiangbo; Yang, Jinli; Geng, Dongsheng; Wang, Dongniu; Li, Ruying; Sun, Xueliang

    2012-01-01

    A floating catalyst chemical vapor deposition method has been developed to synthesize carbon nanotubes doped with a high concentration of nitrogen. Their electrochemical performance as anodes for lithium ion batteries (LIBs) in comparison to pristine carbon nanotubes (CNTs) has been investigated. X-ray photoelectron spectroscopy results indicated that the nitrogen content reaches as high as 16.4 at.%. Bamboo-like compartments were fabricated as shown by high resolution transmission electron microscopy. High concentration nitrogen doped carbon nanotubes (HN-CNTs) show approximately double reversible capacity of CNTs: 494 mAh g-1 vs. 260 mAh g-1, and present a much better rate capability than CNTs. The significantly superior electrochemical performance could be related to the high electrical conductivity and the larger number of defect sites in HN-CNTs for anodes of LIBs.

  13. Space Station Freedom electrical performance model

    Science.gov (United States)

    Hojnicki, Jeffrey S.; Green, Robert D.; Kerslake, Thomas W.; Mckissock, David B.; Trudell, Jeffrey J.

    1993-01-01

    The baseline Space Station Freedom electric power system (EPS) employs photovoltaic (PV) arrays and nickel hydrogen (NiH2) batteries to supply power to housekeeping and user electrical loads via a direct current (dc) distribution system. The EPS was originally designed for an operating life of 30 years through orbital replacement of components. As the design and development of the EPS continues, accurate EPS performance predictions are needed to assess design options, operating scenarios, and resource allocations. To meet these needs, NASA Lewis Research Center (LeRC) has, over a 10 year period, developed SPACE (Station Power Analysis for Capability Evaluation), a computer code designed to predict EPS performance. This paper describes SPACE, its functionality, and its capabilities.

  14. The performance of porous electric heaters

    Energy Technology Data Exchange (ETDEWEB)

    Al-Nimr, M.A.; Naji, M.

    2003-03-01

    The performance of a proposed porous electric heater is investigated. The porous heater exchanges heat with the working fluid through its large volumetric surface area. As a result, it produces lower surface temperature as compared with the conventional heater for the same imposed heating power. Two mathematical models are presented to describe the thermal behavior of both heaters and the predictions of both models are compared at different operating conditions. (author)

  15. Heliocentric phasing performance of electric sail spacecraft

    Science.gov (United States)

    Mengali, Giovanni; Quarta, Alessandro A.; Aliasi, Generoso

    2016-10-01

    We investigate the heliocentric in-orbit repositioning problem of a spacecraft propelled by an Electric Solar Wind Sail. Given an initial circular parking orbit, we look for the heliocentric trajectory that minimizes the time required for the spacecraft to change its azimuthal position, along the initial orbit, of a (prescribed) phasing angle. The in-orbit repositioning problem can be solved using either a drift ahead or a drift behind maneuver and, in general, the flight times for the two cases are different for a given value of the phasing angle. However, there exists a critical azimuthal position, whose value is numerically found, which univocally establishes whether a drift ahead or behind trajectory is superior in terms of flight time it requires for the maneuver to be completed. We solve the optimization problem using an indirect approach for different values of both the spacecraft maximum propulsive acceleration and the phasing angle, and the solution is then specialized to a repositioning problem along the Earth's heliocentric orbit. Finally, we use the simulation results to obtain a first order estimate of the minimum flight times for a scientific mission towards triangular Lagrangian points of the Sun-[Earth+Moon] system.

  16. Investigation on Superior Performance by Fractional Controller for Cart-Servo Laboratory Set-Up

    Directory of Open Access Journals (Sweden)

    Ameya Anil Kesarkar

    2014-01-01

    Full Text Available In this paper, an investigation is made on the superiority of fractional PID controller (PI^alpha D^beta over conventional PID for the cart-servo laboratory set-up. The designed controllers are optimum in the sense of Integral Absolute Error (IAE and Integral Square Error (ISE. The paper contributes in three aspects: 1 Acquiring nonlinear mathematical model for the cart-servo laboratory set-up, 2 Designing fractional and integer order PID for minimizing IAE, ISE, 3 Analyzing the performance of designed controllers for simulated plant model as well as real plant. The results show a significantly superior performance by PI^alpha D^beta as compared to the conventional PID controller.

  17. Performances of electrically heated microgroove vaporizers

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    An electrically heated microgroove vaporizer was proposed. The vaporizer mainly comprised an outer tube, an inner tube and an electrical heater cartridge. Microgrooves were fabricated on the external surface of the inner tube by micro-cutting method,which formed the flow passage for fluid between the external surface of the inner tube and the internal surface of the outer tube.Experiments related to the temperature rise response of water and the thermal conversion efficiency of vaporizer were done to estimate the influences of microgroove's direction, feed flow rate and input voltage on the performances of the vaporizer. The results indicate that the microgroove's direction dominates the vaporizer performance at a lower input voltage. The longitudina lmicrogroove vaporizer exhibits the best performances for the temperature rise response of water and thermal conversion efficiency of vaporizer. For a moderate input voltage, the microgroove's direction and the feed flow rate of water together govern the vaporizer performances. The input voltage becomes the key influencing factor when the vaporizer works at a high input voltage, resulting in the similar performances of longitudinal, oblique and latitudinal microgroove vaporizers.

  18. Superior performance of cone beam tomography in detecting a calcaneus fracture.

    Science.gov (United States)

    Lohse, Christian; Catala-Lehnen, Philip; Regier, Marc; Heiland, Max

    2015-01-01

    Cone beam computed tomography is a state-of-the-art imaging tool, initially developed for dental and maxillofacial application. With its high resolution and low radiation dose, cone beam tomography has been expanding its application fields, for example, to diagnosis of traumata and fractures in the head and neck area. In this study, we demonstrate superior and satisfactory performance of cone beam tomography for the imaging of a calcaneus fracture in comparison to conventional X-ray and computed tomography.

  19. Active vacuum brazing of CNT films to metal substrates for superior electron field emission performance

    Science.gov (United States)

    Longtin, Rémi; Sanchez-Valencia, Juan Ramon; Shorubalko, Ivan; Furrer, Roman; Hack, Erwin; Elsener, Hansrudolf; Gröning, Oliver; Greenwood, Paul; Rupesinghe, Nalin; Teo, Kenneth; Leinenbach, Christian; Gröning, Pierangelo

    2015-02-01

    The joining of macroscopic films of vertically aligned multiwalled carbon nanotubes (CNTs) to titanium substrates is demonstrated by active vacuum brazing at 820 °C with a Ag-Cu-Ti alloy and at 880 °C with a Cu-Sn-Ti-Zr alloy. The brazing methodology was elaborated in order to enable the production of highly electrically and thermally conductive CNT/metal substrate contacts. The interfacial electrical resistances of the joints were measured to be as low as 0.35 Ω. The improved interfacial transport properties in the brazed films lead to superior electron field-emission properties when compared to the as-grown films. An emission current of 150 μA was drawn from the brazed nanotubes at an applied electric field of 0.6 V μm-1. The improvement in electron field-emission is mainly attributed to the reduction of the contact resistance between the nanotubes and the substrate. The joints have high re-melting temperatures up to the solidus temperatures of the alloys; far greater than what is achievable with standard solders, thus expanding the application potential of CNT films to high-current and high-power applications where substantial frictional or resistive heating is expected.

  20. Assessing the Costs and Benefits of the Superior Energy Performance Program

    Energy Technology Data Exchange (ETDEWEB)

    Therkelsen, Peter; McKane, Aimee; Sabouini, Ridah; Evans, Tracy

    2013-07-01

    Industrial companies are seeking to manage energy consumption and costs, mitigate risks associated with energy, and introduce transparency into reports of their energy performance achievements. Forty industrial facilities are participating in the U.S. DOE supported Superior Energy Performance (SEP) program in which facilities implement an energy management system based on the ISO 50001 standard, and pursue third-party verification of their energy performance improvements. SEP certification provides industrial facilities recognition for implementing a consistent, rigorous, internationally recognized business process for continually improving energy performance and achievement of established energy performance improvement targets. This paper focuses on the business value of SEP and ISO 50001, providing an assessment of the costs and benefits associated with SEP implementation at nine SEP-certified facilities across a variety of industrial sectors. These cost-benefit analyses are part of the U.S. DOE?s contribution to the Global Superior Energy Performance (GSEP) partnership, a multi-country effort to demonstrate, using facility data, that energy management system implementation enables companies to improve their energy performance with a greater return on investment than business-as-usual (BAU) activity. To examine the business value of SEP certification, interviews were conducted with SEP-certified facilities. The costs of implementing the SEP program, including internal facility staff time, are described and a marginal payback of SEP certification has been determined. Additionally, more qualitative factors with regard to the business value and challenges related to SEP and ISO 50001 implementation are summarized.

  1. Performance evaluations of demountable electrical connections

    Science.gov (United States)

    Niemann, R. C.; Cha, Y. S.; Hull, J. R.; Buckles, W. E.; Daugherty, M. A.

    Electrical conductors operating in cryogenic environments can require demountable connections along their lengths. The connections must have low resistance and high reliability and should allow ready assembly and disassembly. In this work, the performance of two types of connections has been evaluated. The first connection type is a clamped surface-to-surface joint. The second connection type is a screwed joint that incorporates male and female machine-thread components. The connections for copper conductors have been evaluated experimentally at 77 K. Experimental variables included thread surface treatment and assembly methods. The results of the evaluations are presented.

  2. Insights into collaborative separation process of photogenerated charges and superior performance of solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiangyang, E-mail: lxy081276@126.com; Wang, Shun; Zheng, Haiwu; Gu, Yuzong [Institute of Microsystems Physics and School of Physics and Electronics, Henan University, Kaifeng 475004 (China)

    2016-07-25

    ZnO nanowires/Cu{sub 4}Bi{sub 4}S{sub 9} (ZnO/CBS) and ZnO nanowires/CBS-graphene nanoplates (ZnO/CBS-GNs), as well as two types of solar cells were prepared. The photovoltaic responses of CBS-GNs and ZnO/CBS-GNs can be improved with incorporation of GNs. The transient surface photovoltage (TPV) can provide detailed information on the separation and transport of photogenerated carriers. The multichannel separation process from the TPVs indicates that the macro-photoelectric signals can be attributed to the photogenerated charges separated at the interface of CBS/GNs, rather than CBS/ZnO. The multi-interfacial recombination is the major carrier loss, and the hole selective p-V{sub 2}O{sub 5} can efficiently accelerate the charge extraction to the external circuit. The ZnO/CBS-GNs cell exhibits the superior performance, and the highest efficiency is 10.9%. With the adequate interfaces of CBS/GNs, GNs conductive network, energy level matching, etc., the excitons can easily diffuse to the interface of CBS/GNs, and the separated electrons and holes can be collected quickly, inducing the high photoelectric properties. Here, a facile strategy for solid state solar cells with superior performance presents a potential application.

  3. A new C=C embedded porphyrin sheet with superior oxygen reduction performance

    Institute of Scientific and Technical Information of China (English)

    Yawei Li[1; Shunhong Zhang[2; Jiabing Yu[1; Qian Wang[2; Qiang Sun[1,2,3; Puru Jena[3

    2015-01-01

    C2 is a well-known pseudo-oxygen unit with an electron affinity of 3.4 eV. We show that it can exhibit metal-ion like behavior when embedded in a porphyrin sheet and form a metal-free two-dimensional material with superior oxygen reduction performance. Here, the positively charged C=C units are highly active for oxygen reduction reaction (ORR) via dissociation pathways with a small energy barrier of 0.09 eV, much smaller than that of other non-platinum group metal (non-PGM) ORR catalysts. Using a microkinetics-based model we calculated the partial current density to be 3.0 mA/cm2 at 0.65 V vs. a standard hydrogen electrode (SHE), which is comparable to that of the state-of-the-art Pt/C catalyst. We further confirm that the C=C embedded porphyrin sheet is dynamically and thermally stable with a quasi-direct band gap of 1.14 eV. The superior catalytic performance and geometric stability make the metal-free C=C porphyrin sheet ideal for fuel cell applications.

  4. Insights into collaborative separation process of photogenerated charges and superior performance of solar cells

    Science.gov (United States)

    Liu, Xiangyang; Wang, Shun; Zheng, Haiwu; Gu, Yuzong

    2016-07-01

    ZnO nanowires/Cu4Bi4S9 (ZnO/CBS) and ZnO nanowires/CBS-graphene nanoplates (ZnO/CBS-GNs), as well as two types of solar cells were prepared. The photovoltaic responses of CBS-GNs and ZnO/CBS-GNs can be improved with incorporation of GNs. The transient surface photovoltage (TPV) can provide detailed information on the separation and transport of photogenerated carriers. The multichannel separation process from the TPVs indicates that the macro-photoelectric signals can be attributed to the photogenerated charges separated at the interface of CBS/GNs, rather than CBS/ZnO. The multi-interfacial recombination is the major carrier loss, and the hole selective p-V2O5 can efficiently accelerate the charge extraction to the external circuit. The ZnO/CBS-GNs cell exhibits the superior performance, and the highest efficiency is 10.9%. With the adequate interfaces of CBS/GNs, GNs conductive network, energy level matching, etc., the excitons can easily diffuse to the interface of CBS/GNs, and the separated electrons and holes can be collected quickly, inducing the high photoelectric properties. Here, a facile strategy for solid state solar cells with superior performance presents a potential application.

  5. STRATEGIES FOR SUPERIOR PERFORMANCE IN RECESSIONS: PRO OR COUNTER-CYCLICAL?

    Directory of Open Access Journals (Sweden)

    Claudio Ramos Conti

    2015-04-01

    Full Text Available Recessions are recurring events in which most firms suffer severe impacts while others are less affected or may even prosper. Strategic management has made little progress in understanding such performance differences. In a scenario of decreased demand, intensified competition, and higher uncertainty, most firms try to survive by pro-cyclically cutting costs and investments. But firms could take advantage of undervalued resources in the market to counter-cyclically invest in new business opportunities to overtake competitors. We survey Brazilian firms in various industries about the 2008-2009 recession and analyze data using PLS-SEM. We find that while most firms pro-cyclically reduce costs and investments in recessions, a counter-cyclical strategy of investing in opportunities created by changes in the market enables superior performance. Most successful are firms with a propensity to recognize opportunities, an entrepreneurial orientation to invest, and the flexibility to efficiently implement investments.

  6. Nanotubes within transition metal silicate hollow spheres: Facile preparation and superior lithium storage performances

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fan; An, Yongling; Zhai, Wei; Gao, Xueping [Key Laboratory for Liquid–Solid Structural Evolution & Processing of Materials (Ministry of Education), Jinan 250100 (China); Feng, Jinkui, E-mail: jinkui@sdu.edu.cn [Key Laboratory for Liquid–Solid Structural Evolution & Processing of Materials (Ministry of Education), Jinan 250100 (China); Ci, Lijie [Key Laboratory for Liquid–Solid Structural Evolution & Processing of Materials (Ministry of Education), Jinan 250100 (China); Xiong, Shenglin [School of Materials Science and Engineering, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100 (China)

    2015-10-15

    Highlights: • The hollow Co{sub 2}SiO{sub 4}, MnSiO{sub 3} and CuSiO{sub 3} were successfully prepared by a facile hydrothermal method using SiO{sub 2} nanosphere. • The hollow Co{sub 2}SiO{sub 4}, MnSiO{sub 3} and CuSiO{sub 3} were tested as anode materials for lithium batteries. • The hollow Co{sub 2}SiO{sub 4}, MnSiO{sub 3} and CuSiO{sub 3} delivered superior electrochemical performance. • The lithium storage mechanism is probe via cyclic voltammetry and XPS. - Abstract: A series of transition metal silicate hollow spheres, including cobalt silicate (Co{sub 2}SiO{sub 4}), manganese silicate (MnSiO{sub 3}) and copper silicate (CuSiO{sub 3}.2H{sub 2}O, CuSiO{sub 3} as abbreviation in the text) were prepared via a simple and economic hydrothermal method by using silica spheres as chemical template. Time-dependent experiments confirmed that the resultants formed a novel type of hierarchical structure, hollow spheres assembled by numerous one-dimensional (1D) nanotubes building blocks. For the first time, the transition metal silicate hollow spheres were characterized as novel anode materials of Li-ion battery, which presented superior lithium storage capacities, cycle performance and rate performance. The 1D nanotubes assembly and hollow interior endow this kind of material facilitate fast lithium ion and electron transport and accommodate the big volume change during the conversion reactions. Our study shows that low-cost transition metal silicate with rationally designed nanostructures can be promising anode materials for high capacity lithium-ion battery.

  7. Oxygen vacancy induced bismuth oxyiodide with remarkably increased visible-light absorption and superior photocatalytic performance.

    Science.gov (United States)

    Huang, Yongchao; Li, Haibo; Balogun, Muhammad-Sadeeq; Liu, Wenyue; Tong, Yexiang; Lu, Xihong; Ji, Hongbing

    2014-12-24

    With the increasingly serious environmental problems, photocatalysis has recently attracted a great deal of attention, with particular focus on water and air purification and disinfection. Herein, we show an electroreduction strategy to improve significantly the solar absorption and donor density of BiOI nanosheet photocatalyst by introducing oxygen vacancies. These oxygen-deficient BiOI nanosheets exhibit an unexpected red shift of about 100 nm in light absorption band and 1 order of magnitude improvement in donor density compared to the untreated BiOI nanosheets and show 10 times higher photocatalytic activity than the untreated BiOI nanosheets for methyl orange (MO) degradation under visible light irradiation. Moreover, the as-prepared oxygen-deficient BiOI nanosheets also have excellent cycling stability and superior photocatalytic performance toward other dye pollutants.

  8. Development of an Enhanced Payback Function for the Superior Energy Performance Program

    Energy Technology Data Exchange (ETDEWEB)

    Therkelsen, Peter; Rao, Prakash; McKane, Aimee; Sabouni, Ridah; Sheihing, Paul

    2015-08-03

    The U.S. DOE Superior Energy Performance (SEP) program provides recognition to industrial and commercial facilities that achieve certification to the ISO 50001 energy management system standard and third party verification of energy performance improvements. Over 50 industrial facilities are participating and 28 facilities have been certified in the SEP program. These facilities find value in the robust, data driven energy performance improvement result that the SEP program delivers. Previous analysis of SEP certified facility data demonstrated the cost effectiveness of SEP and identified internal staff time to be the largest cost component related to SEP implementation and certification. This paper analyzes previously reported and newly collected data of costs and benefits associated with the implementation of an ISO 50001 and SEP certification. By disaggregating “sunk energy management system (EnMS) labor costs”, this analysis results in a more accurate and detailed understanding of the costs and benefits of SEP participation. SEP is shown to significantly improve and sustain energy performance and energy cost savings, resulting in a highly attractive return on investment. To illustrate these results, a payback function has been developed and is presented. On average facilities with annual energy spend greater than $2M can expect to implement SEP with a payback of less than 1.5 years. Finally, this paper also observes and details decreasing facility costs associated with implementing ISO 50001 and certifying to the SEP program, as the program has improved from pilot, to demonstration, to full launch.

  9. The Design and Construction of a Battery Electric Vehicle Propulsion System - High Performance Electric Kart Application

    Science.gov (United States)

    Burridge, Mark; Alahakoon, Sanath

    2017-07-01

    This paper presents an electric propulsion system designed specifically to meet the performance specification for a competition racing kart application. The paper presents the procedure for the engineering design, construction and testing of the electric powertrain of the vehicle. High performance electric Go-Kart is not an established technology within Australia. It is expected that this work will provide design guidelines for a high performance electric propulsion system with the capability of forming the basis of a competitive electric kart racing formula for Australian conditions.

  10. Identifying blood biomarkers and physiological processes that distinguish humans with superior performance under psychological stress.

    Directory of Open Access Journals (Sweden)

    Amanda M Cooksey

    Full Text Available BACKGROUND: Attrition of students from aviation training is a serious financial and operational concern for the U.S. Navy. Each late stage navy aviator training failure costs the taxpayer over $1,000,000 and ultimately results in decreased operational readiness of the fleet. Currently, potential aviators are selected based on the Aviation Selection Test Battery (ASTB, which is a series of multiple-choice tests that evaluate basic and aviation-related knowledge and ability. However, the ASTB does not evaluate a person's response to stress. This is important because operating sophisticated aircraft demands exceptional performance and causes high psychological stress. Some people are more resistant to this type of stress, and consequently better able to cope with the demands of naval aviation, than others. METHODOLOGY/PRINCIPAL FINDINGS: Although many psychological studies have examined psychological stress resistance none have taken advantage of the human genome sequence. Here we use high-throughput -omic biology methods and a novel statistical data normalization method to identify plasma proteins associated with human performance under psychological stress. We identified proteins involved in four basic physiological processes: innate immunity, cardiac function, coagulation and plasma lipid physiology. CONCLUSIONS/SIGNIFICANCE: The proteins identified here further elucidate the physiological response to psychological stress and suggest a hypothesis that stress-susceptible pilots may be more prone to shock. This work also provides potential biomarkers for screening humans for capability of superior performance under stress.

  11. Nanocomposites of graphene oxide and upconversion rare-earth nanocrystals with superior optical limiting performance

    KAUST Repository

    Wei, Wei

    2012-04-20

    Upconversion rare-earth nanomaterials (URENs) possess highly efficient near-infrared (NIR), e.g., 980 nm, laser absorption and unique energy upconversion capabilities. On the other hand, graphene and its derivatives, such as graphene oxide (GO), show excellent performance in optical limiting (OL); however, the wavelengths of currently used lasers for OL studies mainly focus on either 532 or 1064 nm. To design new-generation OL materials working at other optical regions, such as the NIR, a novel nanocomposites, GO-URENs, which combines the advantages of both its components, is synthesized by a one-step chemical reaction. Transmission electron microscopy, X-ray diffraction, infrared spectroscopy, and fluorescence studies prove that the α-phase URENs uniformly attach on the GO surface via covalent chemical bonding, which assures highly efficient energy transfer between URENs and GO, and also accounts for the significantly improved OL performance compared to either GO or URENs. The superior OL effect is also observed in the proof-of-concept thin-film product, suggesting immediate applications in making high-performance laser-protecting products and optoelectronic devices. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Identifying Blood Biomarkers and Physiological Processes That Distinguish Humans with Superior Performance under Psychological Stress

    Science.gov (United States)

    Cooksey, Amanda M.; Momen, Nausheen; Stocker, Russell; Burgess, Shane C.

    2009-01-01

    Background Attrition of students from aviation training is a serious financial and operational concern for the U.S. Navy. Each late stage navy aviator training failure costs the taxpayer over $1,000,000 and ultimately results in decreased operational readiness of the fleet. Currently, potential aviators are selected based on the Aviation Selection Test Battery (ASTB), which is a series of multiple-choice tests that evaluate basic and aviation-related knowledge and ability. However, the ASTB does not evaluate a person's response to stress. This is important because operating sophisticated aircraft demands exceptional performance and causes high psychological stress. Some people are more resistant to this type of stress, and consequently better able to cope with the demands of naval aviation, than others. Methodology/Principal Findings Although many psychological studies have examined psychological stress resistance none have taken advantage of the human genome sequence. Here we use high-throughput -omic biology methods and a novel statistical data normalization method to identify plasma proteins associated with human performance under psychological stress. We identified proteins involved in four basic physiological processes: innate immunity, cardiac function, coagulation and plasma lipid physiology. Conclusions/Significance The proteins identified here further elucidate the physiological response to psychological stress and suggest a hypothesis that stress-susceptible pilots may be more prone to shock. This work also provides potential biomarkers for screening humans for capability of superior performance under stress. PMID:20020041

  13. Testing the performance of technical trading rules in the Chinese markets based on superior predictive test

    Science.gov (United States)

    Wang, Shan; Jiang, Zhi-Qiang; Li, Sai-Ping; Zhou, Wei-Xing

    2015-12-01

    Technical trading rules have a long history of being used by practitioners in financial markets. The profitable ability and efficiency of technical trading rules are yet controversial. In this paper, we test the performance of more than seven thousand traditional technical trading rules on the Shanghai Securities Composite Index (SSCI) from May 21, 1992 through June 30, 2013 and China Securities Index 300 (CSI 300) from April 8, 2005 through June 30, 2013 to check whether an effective trading strategy could be found by using the performance measurements based on the return and Sharpe ratio. To correct for the influence of the data-snooping effect, we adopt the Superior Predictive Ability test to evaluate if there exists a trading rule that can significantly outperform the benchmark. The result shows that for SSCI, technical trading rules offer significant profitability, while for CSI 300, this ability is lost. We further partition the SSCI into two sub-series and find that the efficiency of technical trading in sub-series, which have exactly the same spanning period as that of CSI 300, is severely weakened. By testing the trading rules on both indexes with a five-year moving window, we find that during the financial bubble from 2005 to 2007, the effectiveness of technical trading rules is greatly improved. This is consistent with the predictive ability of technical trading rules which appears when the market is less efficient.

  14. Rational design of reduced graphene oxide for superior performance of supercapacitor electrodes

    KAUST Repository

    Rasul, Shahid

    2016-10-24

    Strategies to synthesize reduced graphene oxide (rGO) abound but, in most studies, research teams select one particular oxidation-reduction method without providing a methodic reasoning for doing so. Herein, it is analyzed how diverse oxidation-reduction strategies commonly used can result in considerable performance differences of rGO for supercapacitor applications. Depending on the graphite oxidation method followed, the surface chemistry analysis of the products confirms that there is a marked disparity in the degree of oxidation and the nature of the oxygen functional groups present. Subsequent reduction of the oxidized graphite (using three different methods) showed that the maximum specific capacitance of rGOs produced from the classical Hummers\\' method was 128 F g−1 whereas an analogous material obtained from an improved Hummers\\' method reached ∼274 F g−1 (both via an hydrothermal reduction route). Besides showing that the improved oxidation method results in superior capacitance performance, explained by the higher number of structural defects allied to a surface chemistry where residual hydroxyl and epoxy functional groups predominate, this study highlights the need to rationalize the oxidation-reduction strategies followed when investigating applications of rGO materials.

  15. Superior sensory, motor, and cognitive performance in elderly individuals with multi-year dancing activities

    Directory of Open Access Journals (Sweden)

    Jan-Christoph Kattenstroth

    2010-07-01

    Full Text Available Aging is associated with a progressive decline of mental and physical abilities. Considering the current demographic changes in many civilizations there is an urgent need for measures permitting an independent lifestyle into old age. The critical role of physical exercise in mediating and maintaining physical and mental fitness is well-acknowledged. Dance, in addition to physical activity, combines emotions, social interaction, sensory stimulation, motor coordination and music, thereby creating enriched environmental conditions for human individuals. Here we demonstrate the impact of multi-year (average 16.5 years amateur dancing (AD in a group of elderly subjects (aged 65 to 84 years as compared to education-, gender- and aged-matched controls (CG having no record of dancing or sporting activities. Besides posture and balance parameters, we tested reaction times, motor behavior, tactile and cognitive performance. In each of the different domains investigated, the AD group had a superior performance as compared to the non-dancer CG group. Analysis of individual performance revealed that the best participants of the AD group were not better than individuals of the CG group. Instead, the AD group lacked individuals showing poor performance, which was frequently observed for the CG group. This observation implies that maintaining a regular schedule of dancing into old age can preserve cognitive, motor and perceptual abilities and prevent them from degradation. We conclude that the far-reaching beneficial effects found in the AD group make dance, beyond its ability to facilitate balance and posture, a prime candidate for the preservation of everyday life competence of elderly individuals.

  16. Superior sensory, motor, and cognitive performance in elderly individuals with multi-year dancing activities.

    Science.gov (United States)

    Kattenstroth, Jan-Christoph; Kolankowska, Izabella; Kalisch, Tobias; Dinse, Hubert R

    2010-01-01

    Aging is associated with a progressive decline of mental and physical abilities. Considering the current demographic changes in many civilizations there is an urgent need for measures permitting an independent lifestyle into old age. The critical role of physical exercise in mediating and maintaining physical and mental fitness is well-acknowledged. Dance, in addition to physical activity, combines emotions, social interaction, sensory stimulation, motor coordination and music, thereby creating enriched environmental conditions for human individuals. Here we demonstrate the impact of multi-year (average 16.5 years) amateur dancing (AD) in a group of elderly subjects (aged 65-84 years) as compared to education-, gender- and aged-matched controls (CG) having no record of dancing or sporting activities. Besides posture and balance parameters, we tested reaction times, motor behavior, tactile and cognitive performance. In each of the different domains investigated, the AD group had a superior performance as compared to the non-dancer CG group. Analysis of individual performance revealed that the best participants of the AD group were not better than individuals of the CG group. Instead, the AD group lacked individuals showing poor performance, which was frequently observed for the CG group. This observation implies that maintaining a regular schedule of dancing into old age can preserve cognitive, motor and perceptual abilities and prevent them from degradation. We conclude that the far-reaching beneficial effects found in the AD group make dance, beyond its ability to facilitate balance and posture, a prime candidate for the preservation of everyday life competence of elderly individuals.

  17. Designing Appraisal Pattern for Performance of Superior League Football Teams by Emphasizing on Stakeholders’ Benefits

    Directory of Open Access Journals (Sweden)

    Seyed Mehdi TAYEBI

    2016-03-01

    Full Text Available Performance assessment by stakeholders is a strategic process that this research formed based on Freeman Stakeholders’ theory (1986 and Lee Stakeholders’ model and its goal is replying to following questions in order to present proper model for performance assessment: Who are most important stakeholders of superior football teams? What are their most important purposes? What are most important actions for fulfilling their needs? The research information collected from ministry of sport and youth, federation, club universalities, library and f iled experts and in first stage based on Freeman theory and past studies and experts’ opinions, a questionnaire was developed with Cronbach alpha coefficient of 0.891 and by using Shannon entropy model and TOPSIS method extracted 9 priorities out of 21. In second stage, a second questionnaire was developed with Cronbach alpha coefficient of 0.928 and 20 most important requests out of 71extracted by TOPSIS method. In 3rd stage, a third questionnaire was developed through interview with managers of 3 sup erior leagues and took measures to examine most implorations actions for providing stakeholders requests that 49 executive actions was recognized and performed by QFD model and quality house model indicated relation among requests of stakeholders, actions, weighting and ranked ultimately 24 important actions was recognized and by using results and normalization, performance assessment model extracted from above three processes that indicated victory result and monetary benefits included their most important requests and teams shall take action to establish clear financial and planning unit and shall be assessed periodically.

  18. Superior electrode performance of mesoporous hollow TiO2 microspheres through efficient hierarchical nanostructures

    Science.gov (United States)

    Zhang, Feng; Zhang, Yu; Song, Shuyan; Zhang, Hongjie

    2011-10-01

    Mesoporous hollow TiO2 microspheres with controlled size and hierarchical nanostructures are designed from a process employing in suit template-assisted and hydrothermal methods. The results show that the hollow microspheres composed of mesoporous nanospheres possess very stable reversible capacity of 184 mAh g-1 at 0.25C and exhibit extremely high power of 122 mAh g-1 at the high rate of 10C. The superior high-rate and high-capacity performance of the sample is attributed to the efficient hierarchical nanostructures. The hollow structure could shorten the diffusion length for lithium ion in the microspheres. The large mesoporous channels between the mesoporous nanospheres provide an easily-accessed system which facilitates electrolyte transportation and lithium ion diffusion within the electrode materials. The electrolyte, flooding the mesoporous channels, can also lead to a high electrolyte/electrode contact area, facilitating transport of lithium ions across the electrolyte/electrode interface. The small mesopores in the meosporous nanospheres can make the electrolyte and lithium ion further diffuse into the interior of electrode materials and increase electrolyte/electrode contact area. The small nanoparticles can also ensure high reversible capacity.

  19. Superior mechanical performance of highly porous, anisotropic nanocellulose-montmorillonite aerogels prepared by freeze casting.

    Science.gov (United States)

    Donius, Amalie E; Liu, Andong; Berglund, Lars A; Wegst, Ulrike G K

    2014-09-01

    Directionally solidified nanofibrillated cellulose (NFC)-sodium-montmorillonite (MMT) composite aerogels with a honeycomb-like pore structure were compared with non-directionally frozen aerogels with equiaxed pore structure and identical composition and found to have superior functionalities. To explore structure-property correlations, three different aerogel compositions of 3wt% MMT, and 0.4wt%, 0.8wt%, and 1.2wt% NFC, respectively, were tested. Young׳s modulus, compressive strength and toughness were found to increase with increasing NFC content for both architectures. The modulus increased from 25.8kPa to 386kPa for the isotropic and from 2.13MPa to 3.86MPa for the anisotropic aerogels, the compressive yield strength increased from 3.3kPa to 18.0kPa for the isotropic and from 32.3kPa to 52.5kPa for the anisotropic aerogels, and the toughness increased from 6.3kJ/m(3) to 24.1kJ/m(3) for the isotropic and from 22.9kJ/m(3) to 46.2kJ/m(3) for the anisotropic aerogels. The great range of properties, which can be achieved through compositional as well as architectural variations, makes these aerogels highly attractive for a large range of applications, for which either a specific composition, or a particular pore morphology, or both are required. Finally, because NFC is flammable, gasification experiments were performed, which revealed that the inclusion of MMT increased the heat endurance and shape retention functions of the aerogels dramatically up to 800°C while the mechanical properties were retained up to 300°C.

  20. Performance analysis of electrical circuits /PANE/

    Science.gov (United States)

    Johnson, K. L.; Steinberg, L. L.

    1968-01-01

    Automated statistical and worst case computer program has been designed to perform dc and ac steady circuit analyses. The program determines the worst case circuit performance by solving circuit equations.

  1. FeS anchored reduced graphene oxide nanosheets as advanced anode material with superior high-rate performance for alkaline secondary batteries

    Science.gov (United States)

    Shangguan, Enbo; Guo, Litan; Li, Fei; Wang, Qin; Li, Jing; Li, Quanmin; Chang, Zhaorong; Yuan, Xiao-Zi

    2016-09-01

    A new nanocomposite formulation of the iron-based anode for alkaline secondary batteries is proposed. For the first time, FeS nanoparticles anchored on reduced graphene oxide (RGO) nanosheets are synthesized via a facile, environmentally friendly direct-precipitation approach. In this nanocomposite, FeS nanoparticles are anchored uniformly and tightly on the surface of RGO nanosheets. As an alkaline battery anode, the FeS@RGO electrode delivers a superior high-rate charge/discharge capability and outstanding cycling stability, even at a condition without any conductive additives and a high electrode loading of ∼40 mg cm-2. At high charge/discharge rates of 5C, 10C and 20C (6000 mA g-1), the FeS@RGO electrode presents a specific capacity of ∼288, 258 and 220 mAh g-1, respectively. Moreover, the FeS@RGO electrode exhibits an admirable long cycling stability with a superior capacity retention of 87.6% for 300 cycles at a charge/discharge rate of 2C. The excellent electrochemical properties of the FeS@RGO electrode can be stemmed from the high specific surface area, peculiar electric conductivity and robust sheet-anchored structure of the FeS@RGO nanocomposite. By virtue of its superior fast charge/discharge properties, the FeS@RGO nanocomposite is suitable as an advanced anode material for high-performance alkaline secondary batteries.

  2. Microarray analysis of gene expression after electrical stimulation of the dura mater surrounding the superior sagittal sinus in conscious adult rats

    Institute of Scientific and Technical Information of China (English)

    Jiang Lei; Dong Zhao; Li Fengpeng; Liu Ruozhuo; Qiu Enchao; Wang Xiaolin; Yu Shengyuan

    2014-01-01

    Background The molecular and cellular origins of migraine headache are among the most complex problems in contemporary neurology.Up to now the pathogenesis of migraine still remains unclearly defined.The objective of this study was to explore new factors that may be related to the mechanism of migraine.Methods The present study performed a comprehensive analysis of gene expression in the trigeminal nucleus caudalis induced by electrical stimulation of dura mater surrounding the superior sagittal sinus in conscious rats using microarray analysis followed by quantitative real-time reverse-transcribed polymerase chain reaction (qRT-PCR) verification.Student's two sample t-test was employed when two groups were compared.A P value <0.05 was considered to be statistically significant.Results Comparing the placebo and the electrical stimulation groups,40 genes were determined to be significantly differentially expressed.These significantly differentially expressed genes were involved in many pathways,including transporter activity,tryptophan metabolism,G protein signaling,kinase activity,actin binding,signal transducer activity,anion transport,protein folding,enzyme inhibitor activity,coenzyme metabolism,binding,ion transport,cell adhesion,metal ion transport,oxidoreductase activity,mitochondrion function,and others.Most of the genes were involved in more than 2 pathways.Of particular interest is the up-regulation of Phactr3 and Akap5 and the down-regulation of Kdr.Conclusion These findings may provide important clues for a better understanding of the molecular mechanism of migraine.

  3. Superior electro-optical properties of electrically controlled birefringence mode using solution-derived La{sub 2}O{sub 3} films

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Hae-Chang; Park, Hong-Gyu; Lee, Ju Hwan; Seo, Dae-Shik, E-mail: dsseo@yonsei.ac.kr [Information Display Device Laboratory, Department of Electrical and Electronic Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Oh, Byeong-Yun [ZeSHTech Co., Ltd., Business Incubator, Gwangju Institute of Science and Technology, 123, Cheomdangwagi-ro, Buk-gu, Gwangju 500-712 (Korea, Republic of)

    2015-11-15

    The authors demonstrate a high performance electrically controlled birefringence (ECB) mode with solution-derived La{sub 2}O{sub 3} films at various molar concentrations. Uniform and homogeneous liquid crystal (LC) alignment was spontaneously achieved on the La{sub 2}O{sub 3} films for lanthanum concentrations at ratios greater than and equal to 0.2. A preferred orientation of LC molecules appeared along the filling direction, and the LC alignment was maintained via van der Waals force by nanocrystals of the La{sub 2}O{sub 3} films. The LC alignment mechanism was confirmed by x-ray photoelectron spectroscopy and high-resolution transmission electron microscopy analysis. Superior electro-optical characteristics of the ECB cells constructed with solution-derived La{sub 2}O{sub 3} films were observed, which suggests that the proposed solution-derived La{sub 2}O{sub 3} films have strong potential for use in the production of advanced LC displays.

  4. EHV AC undergrounding electrical power performance and planning

    CERN Document Server

    Benato, Roberto

    2014-01-01

    Analytical methods of cable performance in EHV AC electrical power are discussed in this comprehensive reference. Descriptions of energization, power quality, cable safety constraints and more, guide readers in cable planning and power network operations.

  5. Energy efficiency and performance indicators of European electricity market

    National Research Council Canada - National Science Library

    Constantin Duguleana; Liliana Duguleana

    2015-01-01

    ... characterizing the performance level of power distribution systems. The paper analyzes the evolution of quality indicators of power distribution systems both for countries' level and for population on European market of electricity.

  6. [A comparison of time resolution among auditory, tactile and promontory electrical stimulation--superiority of cochlear implants as human communication aids].

    Science.gov (United States)

    Matsushima, J; Kumagai, M; Harada, C; Takahashi, K; Inuyama, Y; Ifukube, T

    1992-09-01

    Our previous reports showed that second formant information, using a speech coding method, could be transmitted through an electrode on the promontory. However, second formant information can also be transmitted by tactile stimulation. Therefore, to find out whether electrical stimulation of the auditory nerve would be superior to tactile stimulation for our speech coding method, the time resolutions of the two modes of stimulation were compared. The results showed that the time resolution of electrical promontory stimulation was three times better than the time resolution of tactile stimulation of the finger. This indicates that electrical stimulation of the auditory nerve is much better for our speech coding method than tactile stimulation of the finger.

  7. Performance of Batangas II Electric Cooperative, Inc. (Batelec II in the Wholesale Electricity Spot Market

    Directory of Open Access Journals (Sweden)

    IAN JIM SANTOS LAQUI

    2014-08-01

    Full Text Available In the face of electricity reformation, every electric cooperative needs a stable operation. The operational stability of participation in the Power Industry reformation such as Wholesale Electricity Spot Market (WESM depends on the performance of any electricity provider and management of the problems they encountered in new environment. The study aimed to determine the level of performance of Batelec II, which will serve as basis of enhancing the energy trading transaction of Batelec II. Furthermore, it also assesses to identify the problems encountered on the WESM to arrive at a specific action plan. The descriptive method was utilized in the conduct of the study. The study revealed that Batelec II distribute an uninterruptible flow of electricity among its memberconsumers. It also manifest that the price of electricity it serve were competitive enough. This was due to the effort and strategy of Batelec II’s trading team. As part also of efficiency of the performance of Batelec II, they manage to respond to the line trouble quickly. This gives Batelec II a good rating in terms of operations and maintenance. It is noted that problems in the said matter was identified. These were the transmission failure, generation facility outages and change in law. This aspect makes the electricity price go high. In response to the problems identified, the researcher proposed an action plan for the board directors and top management of Batelec II for implementation.

  8. Monitoring and analyzing features of electrical power quality system performance

    Directory of Open Access Journals (Sweden)

    Genci Sharko

    2010-06-01

    Full Text Available Power quality is a set of boundaries that allows electrical systems to function in their intended manner without significant loss of performance or life. The term is used to describe electric power that drives an electrical load and the load's ability to function properly with that electric power. Without the proper quality of the power, an electrical device may malfunction, fail prematurely or not operate at all. There are many reasons why the electric power can be of poor quality and many more causes of such poor quality power. Power quality of power systems, which affects all connected electrical and electronic equipment, is a measure of deviations in voltages, currents, frequency, temperatures, winding forces and torques of particular supply systems and their components. In recent years, a considerable increase in nonlinear loads has been experienced; in particular distributed loads, such as computers, monitors and lighting, and distributed sources. The aim of this paper is to display a way of monitoring and analyzing features of electrical power quality system. As a monitoring example is taken output from power transformer rated at 320 kVA, part of distribution grid of Durres City in Albania.

  9. Decision making in the electricity sector using performance indicators

    Energy Technology Data Exchange (ETDEWEB)

    Domingues, Nuno [ISEL-ADESPA, Lisbon (Portugal); FCT-UNL, Caparica (Portugal); Neves-Silva, Rui; Melo, Joao Joanaz de [FCT-UNL, Caparica (Portugal)

    2017-02-15

    The studies on the electricity sector are usually focused on the supply side, considering consumers as price-takers, i.e. assuming no demand elasticity. The present paper highlights the role of consumers on the electricity sector, assuming that consumers react to electricity prices and make decisions. Many studies focused on the demand side disaggregate consumers by activities, leading to a highly complex analyse. In the present paper, consumers are divided by three main types. In the present paper, the Government makes decisions on the measures to implement to influence the production and the consumption. To study the impact of the Government decisions, the present paper studies and implements a tool: a decision support system. This tool is based on a conceptual model and assists the task of test and analyse the electricity sector using scenarios to obtain a set of performance indicators that would allow to make quantitative balance and to eliminate unfeasible measures. The performance indicators quantify the technical, environmental, social and economical aspects of the electricity sector and help to understand the effect of consumer practices, production technology and Government measures on the electricity sector. Based on the scenarios produced, it is possible to conclude that the price signal is important for consumers and it is a way to guide their behaviour. It is also possible to conclude that is preferable to apply incentives on supporting energy-efficiency measures implementation than on reduce the price of electricity sold to consumers. (orig.)

  10. The impact of strategic planning process variation on superior organizational performance in nonprofit human service organizations providing mental health services

    Science.gov (United States)

    Singh, Karun Krishna

    This research investigated the question: What is the impact of strategic planning process variation on superior organizational performance in nonprofit human service organizations providing mental health services? The study employed a retrospective, cross-sectional, comparison group design using a combination of survey data, unobtrusive agency backup data, and follow-up in-person interview data. The sample was comprised of two main groups of organizations, those that were doing strategic planning and those that were not engaged in strategic planning. Responses were obtained from the chief executive officers of 306 of the 380 randomly selected organizations resulting in a response rate of 81%. Hypotheses were tested using multiple and logistic regression procedures. The major finding of this study was that complete strategic planning is highly correlated with superior organizational performance. The implications of the findings for administration, policy, research, and the social work profession are discussed.

  11. Project Startup: Evaluating the Performance of Electric Buses

    Energy Technology Data Exchange (ETDEWEB)

    2016-04-01

    The National Renewable Energy Laboratory (NREL) is evaluating the in-service performance of fast-charge battery electric buses compared to compressed natural gas (CNG) buses operated by Foothill Transit in West Covina, California. Launched in 2015 in collaboration with the California Air Resources Board, this study aims to improve understanding of the overall use and effectiveness of fast-charge electric buses and associated charging infrastructure in transit operation.

  12. Influential Factors on Deicing Performance of Electrically Conductive Concrete Pavement

    Institute of Scientific and Technical Information of China (English)

    TANG Zuquan; QIAN Jueshi; LI Zhuoqiu; WU Chuanming

    2006-01-01

    The deicing experiment of carbon fiber reinforced electrically conductive concrete (CFRC) slab was conducted in laboratory at first, then the deicing process of CFRC pavement was analyzed by means of finite element method (FEM). At last, based on the energy conservation law and the computing results of finite element method, the influential factors including the setting of electric heating layer, environmental temperature, the thickness of ice, material parameters, and deicing power on deicing performance and energy consumption were discussed.

  13. Performance of Batangas I Electric Cooperative, Inc. (BATELEC I) in the Wholesale Electricity Spot Market (WESM)

    National Research Council Canada - National Science Library

    Ma. Benilda C. Aquino – Dimaunahan

    2014-01-01

    ... I) in participation in the Wholesale Electricity Spot Market (WESM). BATELEC I obtained a high score based on the Key Performance Standard set by the National Electrification Administration for the year 2012. The employees and member-consumers assessed the institutional performance of BATELEC 1 as satisfactory.

  14. Superior Performance Nanocomposites from Uniformly Dispersed Octadecylamine Functionalized Multi-Walled Carbon Nanotubes

    KAUST Repository

    Chen, Ye

    2015-12-08

    Polyetherimide (PEI) is a widely applied as engineering plastic in the electronics, aerospace, and automotive industries but the disadvantages of extremely low conductivity, atmospheric moisture absorption, and poor fluidity at high temperature limits its application. Herein, commercial multi-walled carbon nanotubes (MWCNTs) were modified with a long alkyl chain molecule, octadecylamine (ODA), to produce a uniform dispersion in commercial PEI matrices. Both covalent and noncovalent modification of MWCNTs with ODA, were prepared and compared. Modified MWCNTs were incorporated in PEI matrices to fabricate nanocomposite membranes by a simple casting method. Investigating mechanical properties, thermal stability, and conductivity of the polyetherimide (PEI)/MWCNT composites showed a unique combination of properties, such as high electrical conductivity, high mechanical properties, and high thermal stability at a low content of 1.0 wt % loading of ODA modified MWCNTs. Moreover, electrical resistivity decreased around 10 orders of magnitude with only 0.5 wt % of modified MWCNTs.

  15. Influence of electrical resistivity and machining parameters on electrical discharge machining performance of engineering ceramics.

    Science.gov (United States)

    Ji, Renjie; Liu, Yonghong; Diao, Ruiqiang; Xu, Chenchen; Li, Xiaopeng; Cai, Baoping; Zhang, Yanzhen

    2014-01-01

    Engineering ceramics have been widely used in modern industry for their excellent physical and mechanical properties, and they are difficult to machine owing to their high hardness and brittleness. Electrical discharge machining (EDM) is the appropriate process for machining engineering ceramics provided they are electrically conducting. However, the electrical resistivity of the popular engineering ceramics is higher, and there has been no research on the relationship between the EDM parameters and the electrical resistivity of the engineering ceramics. This paper investigates the effects of the electrical resistivity and EDM parameters such as tool polarity, pulse interval, and electrode material, on the ZnO/Al2O3 ceramic's EDM performance, in terms of the material removal rate (MRR), electrode wear ratio (EWR), and surface roughness (SR). The results show that the electrical resistivity and the EDM parameters have the great influence on the EDM performance. The ZnO/Al2O3 ceramic with the electrical resistivity up to 3410 Ω·cm can be effectively machined by EDM with the copper electrode, the negative tool polarity, and the shorter pulse interval. Under most machining conditions, the MRR increases, and the SR decreases with the decrease of electrical resistivity. Moreover, the tool polarity, and pulse interval affect the EWR, respectively, and the electrical resistivity and electrode material have a combined effect on the EWR. Furthermore, the EDM performance of ZnO/Al2O3 ceramic with the electrical resistivity higher than 687 Ω·cm is obviously different from that with the electrical resistivity lower than 687 Ω·cm, when the electrode material changes. The microstructure character analysis of the machined ZnO/Al2O3 ceramic surface shows that the ZnO/Al2O3 ceramic is removed by melting, evaporation and thermal spalling, and the material from the working fluid and the graphite electrode can transfer to the workpiece surface during electrical discharge

  16. Influence of electrical resistivity and machining parameters on electrical discharge machining performance of engineering ceramics.

    Directory of Open Access Journals (Sweden)

    Renjie Ji

    Full Text Available Engineering ceramics have been widely used in modern industry for their excellent physical and mechanical properties, and they are difficult to machine owing to their high hardness and brittleness. Electrical discharge machining (EDM is the appropriate process for machining engineering ceramics provided they are electrically conducting. However, the electrical resistivity of the popular engineering ceramics is higher, and there has been no research on the relationship between the EDM parameters and the electrical resistivity of the engineering ceramics. This paper investigates the effects of the electrical resistivity and EDM parameters such as tool polarity, pulse interval, and electrode material, on the ZnO/Al2O3 ceramic's EDM performance, in terms of the material removal rate (MRR, electrode wear ratio (EWR, and surface roughness (SR. The results show that the electrical resistivity and the EDM parameters have the great influence on the EDM performance. The ZnO/Al2O3 ceramic with the electrical resistivity up to 3410 Ω·cm can be effectively machined by EDM with the copper electrode, the negative tool polarity, and the shorter pulse interval. Under most machining conditions, the MRR increases, and the SR decreases with the decrease of electrical resistivity. Moreover, the tool polarity, and pulse interval affect the EWR, respectively, and the electrical resistivity and electrode material have a combined effect on the EWR. Furthermore, the EDM performance of ZnO/Al2O3 ceramic with the electrical resistivity higher than 687 Ω·cm is obviously different from that with the electrical resistivity lower than 687 Ω·cm, when the electrode material changes. The microstructure character analysis of the machined ZnO/Al2O3 ceramic surface shows that the ZnO/Al2O3 ceramic is removed by melting, evaporation and thermal spalling, and the material from the working fluid and the graphite electrode can transfer to the workpiece surface during electrical

  17. Performance measurement of electricity suppliers using PROMETHEE and balance scorecard

    Directory of Open Access Journals (Sweden)

    Mona Osati

    2016-06-01

    Full Text Available Performance measurement in energy industry plays an important role on increasing the productivity. Electricity is also among the most essential components of energy in mega cities like Tehran. The lack of a good service in this city may result unpleasant consequences on most civilians who live in this city. This paper presents an empirical investigation to measure the performance of six major electricity contractors in city of Tehran, Iran. The study implements grey numbers to handle any uncertainty associated with numbers. The study has also adopted four main perspectives used in balanced scorecard as part of PROMETHEE method to rank different contractors.

  18. Transient Performance of Electrical System in a Military Vehicle

    Directory of Open Access Journals (Sweden)

    Zang Kemao

    2004-01-01

    Full Text Available Electrical system in a military vehicle is a low voltage (28 V dc system which is an unsymmetrical and nonlinear system made up of silicon-rectifying generator and a battery in parallel. Studies have been carried out using numerical method to calculate its transient performance. State variable and coordinate transformation have been adopted to express the functional modes and its transfer law of the silicon-rectifying generator; the battery is expressed as a simplified equivalent circuit according to its characteristics during transient process: Consequently, the general mathematical model of electrical system in a military vehicle is presented. Examples of electrical systems in somemilitary vehicles have been taken to carry out the calculation of transient performance and the findings have been compared with the test results of an actual vehicle to show that the numerical method designed works.

  19. Origin of the superior performance of (thio)squaramides over (thio)ureas in organocatalysis.

    Science.gov (United States)

    Lu, Tongxiang; Wheeler, Steven E

    2013-11-04

    The Diels-Alder cycloaddition of anthracene and nitrostyrene catalyzed by the squaramide-derived aminocatalysts (Sq) recently reported by Jørgensen and co-workers (Angew. Chem. 2012, 124, 10417; Angew. Chem. Int. Ed. 2012, 51, 10271) has been studied by using modern tools of computational quantum chemistry. This catalyst is compared with analogous urea-, thiourea-, and thiosquaramide-derived aminocatalysts. Ultimately, a thiosquar-amide-derived catalyst is predicted to result in the lowest free-energy barrier, while retaining the same high degree of enantioselectivity as Sq. This stems in part from the superior hydrogen-bonding ability of thiosquaramides, compared to squaramides and (thio)ureas. We also examine the hydrogen-bonding ability of (thio)ureas and (thio)-squaramides in model complexes. In contrast to previous work, we show that aromaticity does not contribute significantly to the enhanced hydrogen-bonding interactions of squaramides. Overall, thiosquaramide, which has not been explored in the context of either organocatalysis or molecular recognition, is predicted to lead to strong, co-planar hydrogen bonds, and should serve as a potent hydrogen-bonding element in a myriad of applications.

  20. Superior supercapacitive performance of hollow activated carbon nanomesh with hierarchical structure derived from poplar catkins

    Science.gov (United States)

    Su, Xiao-Li; Cheng, Ming-Yu; Fu, Lin; Yang, Jing-He; Zheng, Xiu-Cheng; Guan, Xin-Xin

    2017-09-01

    The hollow activated carbon nanomesh (PCACM) with a hierarchical porous structure is derived from biowaste-poplar catkins by in-situ calcination etching with Ni(NO3)2·6H2O and KOH in N2 flow combined with an acid dissolution technique. This procedure not only inherits the natural tube morphology of poplar catkins, but also generates a fascinating nanomesh structure on the walls. PCACM possesses a large specific surface area (SBET = 1893.0 m2 g-1) and high total pore volume (Vp = 1.495 cm3 g-1), and displays an exciting meso-macoporous structure with a concentrated pore size distribution of 4.53 nm. The specific capacitance of PCACM is as high as 314.6 F g-1 at 1.0 A g-1 when used as the electrode materials for supercapacitor. Furthermore, the symmetric supercapacitor of PCACM with 1.0 M Na2SO4 solution as the electrolyte displays a high energy density of 20.86 Wh kg-1 at a power density of 180.13 W kg-1 within a wide voltage rage of 0-1.8 V, which is comparable or even obviously higher than those of other biomass derived carbon reported. It is noteworthy that PCACM also exhibits superior cycling stability and coulombic efficiency. The excellent electrochemical behaviors enable PCACM to be a promising electrode material for supercapacitors.

  1. Performance of Electricity Generation from Bryophyllum Leaf for Practical Utilisation

    Science.gov (United States)

    Khan, Md. Kamrul Alam

    2017-01-01

    Constructing an affordable cost, environment friendly simplified electrical energy source with Pathor Kuchi Leaf (PKL) for power electrifications which will significantly upgrade the life style of 1.6 billion people especially, who live in rural areas of Bangladesh. However, one fifth of the world's population still lack access to electricity-well, mainly in Sub-Saharan Africa and South Asia (Bangladesh, India, Sri Lanka, Pakistan, Nepal and Bhutan). This innovative technology will meet essential requirements as lighting, telecommunication as well as information access. Electrodes are put into the Bryophyllum Pinnatum Leaf (BPL) or Pathor Kuchi Leaf (PKL) sap and they produce substantially sufficient amount of electricity to power energy consumed electronics and electrical appliances. CuSO4.5H2O solution is used as a secondary salt. The role of CuSO4.5H2O solution has been studied. The electrical and chemical properties, a very important factor for PKL electricity generation device have been studied in this research work. The electrical properties are: internal resistance, voltage regulation, energy efficiency, pulse performance, self discharge characteristics, discharge characteristics with load, capacity of the PKL cell, temperature characteristics and life cycle of the PKL cell. The chemical properties are: variation of voltage, current with the variation of [Zn2+], [Cu2+] and time. The performance of the production of the two bi-products (fertilizer and hydrogen gas production) has been studied. Variation of concentration of Zn2+ and Cu2+ with the variation of percentage of the I am grateful to the authority of the Science and technology ministry,Bangladesh for financial support during the research work.

  2. Graphite assisted synthesis of nanoparticles interconnected porous two-dimensional LiMn2O4 nanoplates with superior performance

    Science.gov (United States)

    Tan, X. H.; Liu, H. Q.; Jiang, Y.; Liu, G. Y.; Guo, Y. J.; Wang, H. F.; Sun, L. F.; Chu, W. G.

    2016-10-01

    A facile graphite assisted approach is proposed to synthesize high performance LiMn2O4 nanostructures. Graphite plates with different sizes and thicknesses are found to have different influences on the structure, morphology and performance of LiMn2O4. Larger and thicker graphite plates result in 2-D porous LiMn2O4 nanoplates whereas smaller and thinner ones lead to the formation of dispersed nanoparticles. Despite the smaller lattice constant, the shorter Lisbnd O and longer Mnsbnd O bonds, and the lower BET surface area compared to dispersed LiMn2O4 nanoparticles, LiMn2O4 nanoplates formed by primary nanoparticles with similar sizes and morphologies exhibit the superior performance because of the better interparticle electronic conductivity. LiMn2O4 nanoplates show the discharge capacity of 104 mAh g-1 at 50 C and the capacity retention of 70.0% after 1000 cycles for 1 C at RT, better than the corresponding values, 95 mAh g-1 and 64.5% for dispersed LiMn2O4 nanoparticles, respectively. The more superior performance of LiMn2O4 nanoplates compared to dispersed LiMn2O4 nanoparticles is particularly manifested in the case of lower percentage conductive additive, which is very significant for practical application. This simple, cost effective, green and up scalable approach can also be employed to synthesize other 2-D nanostructured materials.

  3. Tunable Pseudocapacitance in 3D TiO2-δ Nanomembranes Enabling Superior Lithium Storage Performance.

    Science.gov (United States)

    Huang, Shaozhuan; Zhang, Lin; Lu, Xueyi; Liu, Lifeng; Liu, Lixiang; Sun, Xiaolei; Yin, Yin; Oswald, Steffen; Zou, Zhaoyong; Ding, Fei; Schmidt, Oliver G

    2017-01-24

    Nanostructured TiO2 of different polymorphs, mostly prepared by hydro/solvothermal methods, have been extensively studied for more than a decade as anode materials in lithium ion batteries. Enormous efforts have been devoted to improving the electrical conductivity and lithium ion diffusivity in chemically synthesized TiO2 nanostructures. In this work we demonstrate that 3D Ti(3+)-self-doped TiO2 (TiO2-δ) nanomembranes, which are prepared by physical vapor deposition combined with strain-released rolled-up technology, have a great potential to address several of the long-standing challenges associated with TiO2 anodes. The intrinsic electrical conductivity of the TiO2 layer can be significantly improved by the in situ generated Ti(3+), and the amorphous, thin TiO2 nanomembrane provides a shortened Li(+) diffusion pathway. The fabricated material shows a favorable electrochemical reaction mechanism for lithium storage. Further, post-treatments are employed to adjust the Ti(3+) concentration and crystallinity degree in TiO2 nanomembranes, providing an opportunity to investigate the important influences of Ti(3+) self-doping and amorphous structures on the electrochemical processes. With these experiments, the pseudocapacitance contributions in TiO2 nanomembranes with different crystallinity degree are quantified and verified by an in-depth kinetics analysis. Additionally, an ultrathin metallic Ti layer can be included, which further improves the lithium storage properties of the TiO2, giving rise to the state-of-the-art capacity (200 mAh g(-1) at 1 C), excellent rate capability (up to 50 C), and ultralong lifetime (for 5000 cycles at 10 C, with an extraordinary retention of 100%) of TiO2 anodes.

  4. Amended Electric Field Distribution: A Reliable Technique for Electrical Performance Improvement in Nano scale SOI MOSFETs

    Science.gov (United States)

    Ramezani, Zeinab; Orouji, Ali A.

    2017-04-01

    To achieve reliable transistors, we propose a new silicon-on-insulator (SOI) metal-oxide-semiconductor field-effect transistor (MOSFET) with an amended electric field in the channel for improved electrical and thermal performance, with an emphasis on current leakage improvement. The amended electric field leads to lower electric field crowding and thereby we assume enhanced reliability, leakage current, gate-induced drain leakage (GIDL), and electron temperature. To modify the electric field distribution, an additional rectangular metal region (RMR) is utilized in the buried oxide of the SOI MOSFET. The location and dimensions of the RMR have been carefully optimized to achieve the best results. The electrical, thermal, and radiofrequency characteristics of the proposed structure were analyzed using two-dimensional (2-D) numerical simulations and compared with the characteristics of the conventional, fully depleted SOI MOSFET (C-SOI). Also, critical short-channel effects (SCEs) such as threshold voltage, drain-induced barrier lowering (DIBL), subthreshold slope degradation, hot-carrier effect, GIDL, and leakage power consumption are improved. According to the results obtained, the proposed nano SOI MOSFET is a reliable device, especially for use in low-power and high-temperature applications.

  5. Nociceptive behaviors were induced by electrical stimulation of the dura mater surrounding the superior sagittal sinus in conscious adult rats and reduced by morphine and rizatriptan benzoate.

    Science.gov (United States)

    Dong, Zhao; Jiang, Lei; Wang, Xiaohui; Wang, Xiaolin; Yu, Shengyuan

    2011-01-12

    The trigeminovascular nociception induced by electrical stimulation of the dura mater surrounding the superior sagittal sinus in anesthetized animals has been widely used as a model for investigation of the pathophysiology of vascular headache such as migraine. However, little is known whether pain behaviors can be induced using this model in conscious animals. Thus, to establish a new model of trigeminovascular nociception in conscious animals and to examine the effects of morphine and rizatriptan benzoate on nociceptive behaviors in this new model, we electrically stimulated the dura mater surrounding the superior sagittal sinus. We found that grooming and head-flick activities were altered partially in a frequency-dependent way and that frequencies ranging from 10 to 20 Hz more easily provoked these behaviors. Moreover, we also demonstrated that these behaviors were reduced by morphine and rizatriptan benzoate. Thus, this new model will provide a useful and appropriate tool to directly assess changes in the intensity of pain for further investigation of pathophysiological mechanisms of migraine in conscious animals.

  6. Lignocellulose Nanofiber-Reinforced Polystyrene Produced from Composite Microspheres Obtained in Suspension Polymerization Shows Superior Mechanical Performance.

    Science.gov (United States)

    Ballner, Daniel; Herzele, Sabine; Keckes, Jozef; Edler, Matthias; Griesser, Thomas; Saake, Bodo; Liebner, Falk; Potthast, Antje; Paulik, Christian; Gindl-Altmutter, Wolfgang

    2016-06-01

    A facile approach to obtaining cellulose nanofiber-reinforced polystyrene with greatly improved mechanical performance compared to unreinforced polystyrene is presented. Cellulose nanofibers were obtained by mechanical fibrillation of partially delignified wood (MFLC) and compared to nanofibers obtained from bleached pulp. Residual hemicellulose and lignin imparted amphiphilic surface chemical character to MFLC, which enabled the stabilization of emulsions of styrene in water. Upon suspension polymerization of styrene from the emulsion, polystyrene microspheres coated in MFLC were obtained. When processed into polymer sheets by hot-pressing, improved bending strength and superior impact toughness was observed for the polystyrene-MFLC composite compared to the un-reinforced polystyrene.

  7. Toward a science of exceptional achievement: attaining superior performance through deliberate practice.

    Science.gov (United States)

    Ericsson, K Anders; Nandagopal, Kiruthiga; Roring, Roy W

    2009-08-01

    Exceptional performance is frequently attributed to genetic differences in talent. Since Sir Francis Galton's book, Hereditary Genius, many scientists have cited heritable factors that set limits of performance and only allow some individuals to attain exceptional levels. However, thus far these accounts have not explicated the causal processes involved in the activation and expression of unique genes in DNA that lead to the emergence of distinctive physiological attributes and cognitive capacities (innate talent). This article argues on the basis of our current knowledge that it is possible to account for the development of elite performance among healthy children without recourse to innate talent (genetic endowment)--excepting the innate determinants of body size. Our account is based on the expert-performance approach and proposes that the distinctive characteristics of exceptional performers are the result of adaptations to extended and intense practice activities that selectively activate dormant genes that are contained within all healthy individuals' DNA. Furthermore, the theoretical framework of expert performance explains the apparent emergence of early talent by identifying factors that influence starting ages for training and the accumulated engagement in sustained extended deliberate practice, such as motivation, parental support, and access to the best training environments and teachers. In sum, our empirical investigations and extensive reviews show that the development of expert performance will be primarily constrained by individuals' engagement in deliberate practice and the quality of the available training resources.

  8. Identifying Blood Biomarkers and Physiological Processes That Distinguish Humans with Superior Performance under Psychological Stress

    Science.gov (United States)

    2009-12-18

    Analysis of the factors contributing to serum retinol binding protein and transthyretin levels in Japanese adults. J Atheroscler Thromb 13: 209–215. 23...susceptible low perform- ing colleagues, we compared expression levels of low and median- scoring vs. high-scoring performers. This resulted in nine...effect of catecholamines (eg. epinephrine) either by increasing the release or preventing the reuptake of catecholamines at a pre-synaptic level [11,12

  9. NREL Evaluates Performance of Fast-Charge Electric Buses

    Energy Technology Data Exchange (ETDEWEB)

    2016-09-16

    This real-world performance evaluation is designed to enhance understanding of the overall usage and effectiveness of electric buses in transit operation and to provide unbiased technical information to other agencies interested in adding such vehicles to their fleets. Initial results indicate that the electric buses under study offer significant fuel and emissions savings. The final results will help Foothill Transit optimize the energy-saving potential of its transit fleet. NREL's performance evaluations help vehicle manufacturers fine-tune their designs and help fleet managers select fuel-efficient, low-emission vehicles that meet their bottom line and operational goals. help Foothill Transit optimize the energy-saving potential of its transit fleet. NREL's performance evaluations help vehicle manufacturers fine-tune their designs and help fleet managers select fuel-efficient, low-emission vehicles that meet their bottom line and operational goals.

  10. Antisaccade Performance in Schizophrenia: A Neural Model of Decision Making in the Superior Colliculus

    Directory of Open Access Journals (Sweden)

    Vassilis eCutsuridis

    2014-02-01

    Full Text Available Antisaccade performance deficits in schizophrenia are generally interpreted as an impaired top-down inhibitory signal failing to suppress the erroneous response. We recorded the antisaccade performance (error rates and latencies of healthy and schizophrenia subjects performing the mirror antisaccade task. A neural rise-to-threshold model of antisaccade performance was developed to uncover the biophysical mechanisms giving rise to the observed deficits in schizophrenia. Schizophrenia patients displayed greater variability in the antisaccade and corrected antisaccade latency distributions, increased error rates and decreased corrected errors, relative to healthy participants. Our model showed that i increased variability is due to a more noisy accumulation of information by schizophrenia patients, but their confidence level required before making a decision is unaffected, and ii competition between the correct and erroneous decision processes, and not a third top-down inhibitory signal of the erroneous response, accounts for the antisaccade performance of healthy and schizophrenia subjects. Local competition further ensured that a correct antisaccade is never followed by an error prosaccade.

  11. High-performance hybrid pervaporation membranes with superior hydrothermal and acid stability

    NARCIS (Netherlands)

    H.L. Castricum; R. Kreiter; H.M. van Veen; D.H.A. Blank; J.F. Vente; J.E. ten Elshof

    2008-01-01

    A new organic-inorganic hybrid membrane has been prepared with exceptional performance in dewatering applications. The only precursor used in the sol-gel synthesis of the selective layer was organically linked 1,2-bis(triethoxysilyl)ethane (BTESE). The microporous structure of this layer enables sel

  12. White Matter Microstructure in Superior Longitudinal Fasciculus Associated with Spatial Working Memory Performance in Children

    DEFF Research Database (Denmark)

    Vestergaard, Martin; Madsen, Kathrine Skak; Baaré, William F C

    2011-01-01

    memory (SWM) performance improves significantly throughout the childhood years, and several lines of evidence implicate the left fronto-parietal cortices and connecting fiber tracts in SWM processing. Here we report results from a study of 76 typically developing children, 7 to 13 years of age. We...

  13. Measurement and Evaluation of Heating Performance of Heat Pump Systems Using Wasted Heat from Electric Devices for an Electric Bus

    OpenAIRE

    Moo-Yeon Lee; Jong-Phil Won; Chung-Won Cho; Ho-Seong Lee

    2012-01-01

    The objective of this study is to investigate heating performance characteristics of a coolant source heat pump using the wasted heat from electric devices for an electric bus. The heat pump, using R-134a, is designed for heating a passengers’ compartment by using discharged energy from the coolant of electric devices, such as motors and inverters of the electric bus. The heating performance of the heat pump was tested by varying the operating parameters, such as outdoor temperature and volum...

  14. Effect of Cerium on Mechanical Performance and Electrical Conductivity of Aluminum Rod for Electrical Purpose

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The effect of rare earth element Ce on mechanical performance and electrical conductivity of aluminum rod for electrical purpose were studied under industrial production condition. Using optical microscope, SEM, TEM, EDS and X-ray diffractometer, the microstructure and phase composition of aluminum rod were measured and analyzed. The results indicate that the content of rare earth element Ce is between 0.05%~0.16% in the aluminum rod for electrical purpose. Its tensile strength is enhanced to some extent. The research also discovers that the tensile strength is enhanced remarkably with impurity element Si content increases. Because influence of Si is big to the conductivity, the Si content should be controlled continuously strictly in the aluminum for electrical purpose. Adding rare earth element Ce reduces the solid solubility of Si in the aluminum matrix, and the negative effect of Si on the aluminum conductor reduces effectively. So the limit of in Si content in aluminum rod for electrical purpose can be relaxed moderately.

  15. A framework for the integration of Green and Lean Six Sigma for superior sustainability performance

    DEFF Research Database (Denmark)

    Cherrafi, Anass; Elfezazi, Said; Govindan, Kannan

    2017-01-01

    Evidence suggests that Lean, Six Sigma and Green approaches make a positive contribution to the economic, social and environmental (i.e. sustainability) performance of organisations. However, evidence also suggests that organisations have found their integration and implementation challenging....... The purpose of this research is therefore to present a framework that methodically guides companies through a five stages and sixteen steps process to effectively integrate and implement the Green, Lean and Six Sigma approaches to improve their sustainability performance. To achieve this, a critical review...... of industries. The results showed that the integration of Lean Six Sigma and Green helped the organisations to averagely reduce their resources consumption from 20 to 40% and minimise the cost of energy and mass streams by 7–12%. The application of the framework should be gradual, the companies should assess...

  16. Superior recognition performance for happy masked and unmasked faces in both younger and older adults.

    Directory of Open Access Journals (Sweden)

    Joakim eSvard

    2012-11-01

    Full Text Available In the aging literature it has been shown that even though emotion recognition performance decreases with age, the decrease is less for happiness than other facial expressions. Studies in younger adults have also revealed that happy faces are more strongly attended to and better recognized than other emotional facial expressions. Thus, there might be a more age independent happy face advantage in facial expression recognition. By using a backward masking paradigm and varying stimulus onset asynchronies (17–267 ms the temporal development of a happy face advantage, on a continuum from low to high levels of visibility, was examined in younger and older adults. Results showed that across age groups, recognition performance for happy faces was better than for neutral and fearful faces at durations longer than 50 ms. Importantly, the results showed a happy face advantage already during early processing of emotional faces in both younger and older adults. This advantage is discussed in terms of processing of salient perceptual features and elaborative processing of the happy face. We also investigate the combined effect of age and neuroticism on emotional face processing. The rationale was previous findings of age related differences in physiological arousal to emotional pictures and a relation between arousal and neuroticism. Across all durations, there was an interaction between age and neuroticism, showing that being high in neuroticism might be disadvantageous for younger, but not older adults’ emotion recognition performance during arousal enhancing tasks. These results indicate that there is a relation between aging, neuroticism, and performance, potentially related to physiological arousal.

  17. Performance of the Lester battery charger in electric vehicles

    Science.gov (United States)

    Vivian, H. C.; Bryant, J. A.

    1984-01-01

    Tests are performed on an improved battery charger. The primary purpose of the testing is to develop test methodologies for battery charger evaluation. Tests are developed to characterize the charger in terms of its charge algorithm and to assess the effects of battery initial state of charge and temperature on charger and battery efficiency. Tests show this charger to be a considerable improvement in the state of the art for electric vehicle chargers.

  18. Cobalt-based metal organic framework with superior lithium anodic performance

    Science.gov (United States)

    Hu, Xiaoshi; Hu, Huiping; Li, Chao; Li, Tian; Lou, Xiaobing; Chen, Qun; Hu, Bingwen

    2016-10-01

    The reversible charging of a Co-1,4-benzenedicarboxylate MOF (Co-BDC MOF) prepared via an one-pot solvothermal method was studied for use as the anode in a Li-ion cell. It was found that this MOF anode provides high reversible capacities (1090 and 611 mA h g-1 at current densities of 0.2 and 1 A g-1, respectively), and an impressive rate performance. Such an outstanding Li-ion storage property has not been reported previously for the LIB anodes within the MOFs category. Ex-situ X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (IR) studies of this material at different state of charge suggest that cobalt stays at Co2+ state during discharge/charge process, so that in this case Li+ may be inserted into the organic moiety without the direct participation of cobalt ions.

  19. Multifunctional graphene sheets embedded in silicone encapsulant for superior performance of light-emitting diodes.

    Science.gov (United States)

    Lee, Seungae; Hong, Jin-Yong; Jang, Jyongsik

    2013-07-23

    Graphene nanosheets with uniform shape are successfully incorporated into a silicone encapsulant of a light-emitting diode (LED) using a solvent-exchange approach which is a facile and straightforward method. The graphene nanosheets embedded in the silicone encapsulant have a multifunctional role which improves the performance of light-emitting diodes. The presence of graphene gives rise to effective heat dissipation, improvement of protection ability from external stimuli, such as moisture and hazardous gas, and enhancement of mechanical properties such as elastic modulus and fracture toughness. Consequently, the LEDs composed of a graphene-embedded silicone encapsulant exhibit long-term stability without loss of luminous efficiency by addition of relatively small amounts of graphene. This novel strategy offers a feasible candidate for their practical or industrial applications.

  20. TiO2 hollow microspheres with mesoporous surface: Superior adsorption performance for dye removal

    Science.gov (United States)

    Wang, Ran; Cai, Xia; Shen, Fenglei

    2014-06-01

    TiO2 hollow microspheres with mesoporous surface were synthesized by a facile template-assisted solvothermal reaction. The adsorption performance of TiO2 hollow microspheres for removing Methylene Blue from aqueous solution has been investigated. The comparative adsorption study indicated that adsorption capacity of TiO2 hollow microspheres with mesoporous surface is markedly higher than that of solid microsphere. The equilibrium data fitted well with the Langmuir model and the maximum adsorption capacity reached 196.83 mg/g. The kinetics of dye adsorption followed the pseudo-second-order model and the adsorbed dye could be degraded completely by the subsequent photocatalytic process. These TiO2 hollow microspheres can be considered as a low-cost alternative adsorbent for removal of organic pollutants from wastewater.

  1. Lead-carbon electrode designed for renewable energy storage with superior performance in partial state of charge operation

    Science.gov (United States)

    Zhang, Wen-Li; Yin, Jian; Lin, Zhe-Qi; Shi, Jun; Wang, Can; Liu, De-Bo; Wang, Yue; Bao, Jin-Peng; Lin, Hai-Bo

    2017-02-01

    Renewable energy storage is a key issue in our modern electricity-powered society. Lead acid batteries (LABs) are operated at partial state of charge in renewable energy storage system, which causes the sulfation and capacity fading of Pb electrode. Lead-carbon composite electrode is a good solution to the sulfation problem of LAB. In this paper, a rice-husk-derived hierarchically porous carbon with micrometer-sized large pores (denoted as RHC) has been used as the component of lead-carbon composite electrode. Scanning electron microscopy was used to characterize the morphology of lead-carbon composite electrode. Electrochemical impedance spectroscopy was used to determine the charge transfer capability of lead-carbon composite electrode. Both full charge-discharge method and charge-discharge method operating at harsh partial state of charge condition have been used to prove the superior energy storage capability of lead-carbon composite electrode. Experiment results prove that the micrometer-sized pores of RHC are beneficial to the construction and stability of lead-carbon composite electrode. Microporous carbon material with high surface area is not suitable for the construction of lead-carbon electrode due to the ruin of lead-carbon structure caused by severe electrochemical hydrogen evolution.

  2. Facile fabrication of graphene/nickel oxide composite with superior supercapacitance performance by using alcohols-reduced graphene as substrate

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Peng [School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006 (China); Zhang, Haiyan, E-mail: hyzhang@gdut.edu.cn [School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006 (China); Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter, Guangzhou 510006 (China); Chen, Yiming [School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006 (China); Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter, Guangzhou 510006 (China); Li, Zhenghui; Huang, Zhikun; Xu, Xingfa [School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006 (China); Li, Yunyong; Shi, Zhicong [School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006 (China); Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter, Guangzhou 510006 (China)

    2015-09-25

    Highlights: • G/NiO was synthesized by using alcohols-reduced graphene as substrate. • G/NiO presents a globule-on-sheet structure and reveals a synergistic effect. • G/NiO displays high specific capacitance and superior cycling stability. - Abstract: Graphene/nickel oxide composite (G/NiO) was synthesized through a facile hydrothermal method and subsequently microwave thermal treatment by using alcohols-reduced graphene as substrate. The as-prepared G/NiO was characterized by X-ray diffraction, Raman spectra, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscope and transmission electron microscope. The results indicate that the graphene oxide has been successfully reduced to graphene, and NiO nanoparticles are homogeneous anchored on the surface of graphene, forming a globule-on-sheet structure. The loading content of NiO nanoparticles anchoring on the surface of graphene nanosheets can be controlled by adjusting the hydrothermal temperature. The G/NiO displays superior electrochemical performance with a specific capacitance of 530 F g{sup −1} at 1 A g{sup −1} in 2 M of NaOH. After 5000 cycles, the supercapacitor still maintains a specific capacitance of 490 F g{sup −1} (92% retention of the initial capacity), exhibiting excellent cycling stability.

  3. Superior lithium storage performance of hierarchical porous vanadium pentoxide nanofibers for lithium ion battery cathodes

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Bo [Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing 100083 (China); Energy & Materials Engineering Centre, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); National Key Laboratory of Power Sources, Tianjin Institute of Power Sources, Tianjin 300381 (China); Li, Xifei, E-mail: xfli2011@hotmail.com [Energy & Materials Engineering Centre, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Bai, Zhimin, E-mail: zhimibai@cugb.edu.cn [Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing 100083 (China); Li, Minsi [Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026 (China); Dong, Lei; Xiong, Dongbin [Energy & Materials Engineering Centre, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Li, Dejun, E-mail: dejunli@mail.tjnu.edu.cn [Energy & Materials Engineering Centre, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China)

    2015-06-15

    Highlights: • Hierarchical porous vanadium pentoxide nanofibers were synthesized by electrospinning. • V{sub 2}O{sub 5} nanofibers showed much enhanced lithium storage performance. • Kinetics process of electrospinning V{sub 2}O{sub 5} nanofibers was studied by means of EIS for the first time. • Strategies to enhance the electrochemical performance of V{sub 2}O{sub 5} electrode were concluded. - Abstract: The hierarchical V{sub 2}O{sub 5} nanofibers cathode materials with diameter of 200–400 nm are successfully synthesized via an electrospinning followed by annealing. Powder X-ray diffraction (XRD) pattern confirms the formation of phase-pure product. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) obviously display the hierarchical porous nanofibers constructed by attached tiny vanadium oxide nanoplates. Electrochemical behavior of the as-prepared product is systematically studied using galvanostatic charge/discharge testing, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). It turns out that in comparison to the commercial V{sub 2}O{sub 5} and other unique nanostructured materials in the literature, our V{sub 2}O{sub 5} nanofibers show much enhanced lithium storage capacity, improved cyclic stability, and higher rate capability. After 100 cycles at a current density of 800 mA g{sup −1}, the specific capacity of the V{sub 2}O{sub 5} nanofibers retain 133.9 mAh g{sup −1}, corresponding to high capacity retention of 96.05%. More importantly, the EIS at various discharge depths clearly reveal the kinetics process of the V{sub 2}O{sub 5} cathode reaction with lithium. Based on our results, the possible approach to improve the specific capacity and rate capability of the V{sub 2}O{sub 5} cathode material is proposed. It is expected that this study could accelerate the development of V{sub 2}O{sub 5} cathode in rechargeable lithium ion batteries.

  4. Selection for superior growth advances the onset of puberty and increases reproductive performance in ewe lambs.

    Science.gov (United States)

    Rosales Nieto, C A; Ferguson, M B; Macleay, C A; Briegel, J R; Martin, G B; Thompson, A N

    2013-06-01

    The reproductive efficiency of the entire sheep flock could be improved if ewe lambs go through puberty early and produce their first lamb at 1 year of age. The onset of puberty is linked to the attainment of critical body mass, and therefore we tested whether it would be influenced by genetic selection for growth rate or for rate of accumulation of muscle or fat. We studied 136 Merino ewe lambs with phenotypic values for depth of eye muscle (EMD) and fat (FAT) and Australian Sheep Breeding Values at post-weaning age (200 days) for live weight (PWT), eye muscle depth (PEMD) and fat depth (PFAT). First oestrus was detected with testosterone-treated wethers and then entire rams as the ewes progressed from 6 to 10 months of age. Blood concentrations of leptin and IGF-I were measured to test whether they were related to production traits and reproductive performance (puberty, fertility and reproductive rate). In total, 97% of the lambs reached first oestrus at average weight 39.4 ± 0.4 kg (mean ± s.e.m.) and age 219 days (range 163 to 301). Age at first oestrus decreased with increases in values for PWT (P growth can accelerate the onset of puberty and increase fertility and reproductive rate of Merino ewe lambs. The metabolic hormones, IGF-I and leptin, might act as a physiological link between the growing tissues and the reproductive axis.

  5. Vertical jumping performance of bonobo (Pan paniscus) suggests superior muscle properties.

    Science.gov (United States)

    Scholz, Melanie N; D'Août, Kristiaan; Bobbert, Maarten F; Aerts, Peter

    2006-09-07

    Vertical jumping was used to assess muscle mechanical output in bonobos and comparisons were drawn to human jumping. Jump height, defined as the vertical displacement of the body centre of mass during the airborne phase, was determined for three bonobos of varying age and sex. All bonobos reached jump heights above 0.7 m, which greatly exceeds typical human maximal performance (0.3-0.4m). Jumps by one male bonobo (34 kg) and one human male (61.5 kg) were analysed using an inverse dynamics approach. Despite the difference in size, the mechanical output delivered by the bonobo and the human jumper during the push-off was similar: about 450 J, with a peak power output close to 3000 W. In the bonobo, most of the mechanical output was generated at the hips. To account for the mechanical output, the muscles actuating the bonobo's hips (directly and indirectly) must deliver muscle-mass-specific power and work output of 615 Wkg-1 and 92 Jkg-1, respectively. This was twice the output expected on the basis of muscle mass specific work and power in other jumping animals but seems physiologically possible. We suggest that the difference is due to a higher specific force (force per unit of cross-sectional area) in the bonobo.

  6. The Fos expression in rat brain following electrical stimulation of dura mater surrounding the superior sagittal sinus changed with the pre-treatment of rizatriptan benzoate.

    Science.gov (United States)

    Wang, Xiaolin; Yu, Shengyuan; Dong, Zhao; Jiang, Lei

    2011-01-07

    Fos expression in the brain was systematically investigated by means of immunohistochemical staining after electrical stimulation of the dura mater surrounding the superior sagittal sinus in conscious rats. Fos-like immunoreactive neurons are distributed mainly in the upper cervical spinal cord, spinal trigeminal nucleus caudal part, raphe magnus nucleus, periaqueductal gray, ventromedial hypothalamic nucleus, and mediodorsal thalamus nucleus. With the pre-treatment of intraperitoneal injection of rizatriptan benzoate, the number of Fos-like immunoreactive neurons decreased in the spinal trigeminal nucleus caudal part and raphe magnus nucleus, increased in the periaqueductal gray, and remained unchanged in the ventromedial hypothalamic nucleus and mediodorsal thalamus nucleus. These results provide morphological evidence that the nuclei described above are involved in the development and maintenance of the trigeminovascular headache.

  7. Portafolios electrónicos y educación superior en España: Situación y tendencias

    Directory of Open Access Journals (Sweden)

    Elena Barberá

    2009-01-01

    Full Text Available En el marco de la consolidación de la RED de portafolios electrónicos (e-portafolios en el estado español, el presente artículo expone, los marcos conceptuales que guían las diferentes propuestas en el diseño y la implementación de e-portafolios en la educación superior. En este texto se realiza una cierta revisión sobre estas perspectivas teóricas. También se aborda genéricamente las tipologías de e-portafolios que se relacionan con el conocimiento práctico dirigido por un enfoque de desarrollo competencial y se finaliza el artículo apuntando líneas de desarrollo y aplicación futuras que emergen de nuevas demandas y necesidades en el campo educativo y social.

  8. Portafolios electrónicos y educación superior en España: Situación y tendencias

    Directory of Open Access Journals (Sweden)

    Elena Barberà

    2016-01-01

    Full Text Available En el marco de la consolidación de la RED de portafolio s electrónicos (e - portafolios en el estado español, el presente artículo expone, los marcos conceptuales que guían las diferentes propuestas en el diseño y la implementación de e - portafolios en la educación superior. En este texto se realiza una cierta re visión sobre estas perspectivas teóricas. También se aborda genéricamente las tipologías de e - portafolios que se relacionan con el conocimiento práctico dirigido por un enfoque de desarrollo competencial y se finaliza el artículo apuntando líneas de desarr ollo y aplicación futuras que emergen de nuevas demandas y necesidades en el campo educativo y social.

  9. Design of a 200kW electric powertrain for a high performance electric vehicle

    Directory of Open Access Journals (Sweden)

    Wilmar Martinez

    2016-09-01

    Full Text Available With the purpose of designing the electric powertrain of a high performance electric vehicle capable of running a quarter mile in 10 seconds, firstly it is necessary to calculate the required energy, torque, and power in order to size and select the suitable storage components and electric motors. Secondly, an assessment of the powertrain arrangement is needed to choose the best internal configuration of the vehicle and guarantee the highest efficiency possible. Finally, a design of the power conversion stages, specifically the DC-DC converter that interfaces the storage unit with the electric motors, is required as well. This paper shows the energy calculation procedure based on a longitudinal dynamic model of the vehicle and the selection method of the storage components and motors needed for this application, as well as the design of two 100kW interleaved boost converters with coupled inductors. In addition, a novel operation of the interleaved boost converter is proposed in order to increase the efficiency of the converter. As a result, the designed converter achieved a power density of 24,2kW/kg with an efficiency of 98 %, which was validated by experimental tests of a low power prototype.

  10. Cost and Performance Assumptions for Modeling Electricity Generation Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Tidball, Rick [ICF International, Fairfax, VA (United States); Bluestein, Joel [ICF International, Fairfax, VA (United States); Rodriguez, Nick [ICF International, Fairfax, VA (United States); Knoke, Stu [ICF International, Fairfax, VA (United States)

    2010-11-01

    The goal of this project was to compare and contrast utility scale power plant characteristics used in data sets that support energy market models. Characteristics include both technology cost and technology performance projections to the year 2050. Cost parameters include installed capital costs and operation and maintenance (O&M) costs. Performance parameters include plant size, heat rate, capacity factor or availability factor, and plant lifetime. Conventional, renewable, and emerging electricity generating technologies were considered. Six data sets, each associated with a different model, were selected. Two of the data sets represent modeled results, not direct model inputs. These two data sets include cost and performance improvements that result from increased deployment as well as resulting capacity factors estimated from particular model runs; other data sets represent model input data. For the technologies contained in each data set, the levelized cost of energy (LCOE) was also evaluated, according to published cost, performance, and fuel assumptions.

  11. Cost and Performance Assumptions for Modeling Electricity Generation Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Tidball, R.; Bluestein, J.; Rodriguez, N.; Knoke, S.

    2010-11-01

    The goal of this project was to compare and contrast utility scale power plant characteristics used in data sets that support energy market models. Characteristics include both technology cost and technology performance projections to the year 2050. Cost parameters include installed capital costs and operation and maintenance (O&M) costs. Performance parameters include plant size, heat rate, capacity factor or availability factor, and plant lifetime. Conventional, renewable, and emerging electricity generating technologies were considered. Six data sets, each associated with a different model, were selected. Two of the data sets represent modeled results, not direct model inputs. These two data sets include cost and performance improvements that result from increased deployment as well as resulting capacity factors estimated from particular model runs; other data sets represent model input data. For the technologies contained in each data set, the levelized cost of energy (LCOE) was also evaluated, according to published cost, performance, and fuel assumptions.

  12. The control algorithm improving performance of electric load simulator

    Science.gov (United States)

    Guo, Chenxia; Yang, Ruifeng; Zhang, Peng; Fu, Mengyao

    2017-01-01

    In order to improve dynamic performance and signal tracking accuracy of electric load simulator, the influence of the moment of inertia, stiffness, friction, gaps and other factors on the system performance were analyzed on the basis of researching the working principle of load simulator in this paper. The PID controller based on Wavelet Neural Network was used to achieve the friction nonlinear compensation, while the gap inverse model was used to compensate the gap nonlinear. The compensation results were simulated by MATLAB software. It was shown that the follow-up performance of sine response curve of the system became better after compensating, the track error was significantly reduced, the accuracy was improved greatly and the system dynamic performance was improved.

  13. The tzero electric sports car : how electric vehicles can achieve both high performance and high efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, A.N.; Gage, T.B. [AC Propulsion, San Dimas, CA (United States)

    2000-07-01

    The development of a high-performance electric sports car by AC Propulsion was described along with a status report on the progress in developing the product-certified version. The development of the tzero car began in 1996. In-use testing and safety certification of prototypes is currently underway. The tzero is powered by a high-performance induction motor operated at 37 per cent higher peak current than allowed in a standard system since periods of peak power are limited to only a few seconds. The car, which can accelerate from 0 to 60 mph in 4.1 seconds, is considered to be one of the most energy-efficient cars on the road. Since the tzero will likely be sold without subsidy and since the market size for the tzero is expected to be small, in the order of 1000 units per year, it will have to be sold at a high enough price to cover the costs of small-volume production. AC Propulsion is hopeful that it may even be the first electric vehicle to be sold at a profit. Its technology and image are expected to present examples for other electric vehicles. The paper also included a comprehensive technical description of the car and its systems, such as the power electronics unit, traction converter, charger, auxiliary power supply, 12V battery, recharge interface, battery pack, battery modules and powertrain control. 4 tabs., 15 figs.

  14. Hierarchical porous NiCo2O4 nanosheet arrays directly grown on carbon cloth with superior lithium storage performance.

    Science.gov (United States)

    Zhao, Li; Wang, Lei; Yu, Peng; Tian, Chungui; Feng, He; Diao, Zhongwei; Fu, Honggang

    2017-03-23

    Binary metal oxides have been explored as advanced candidates in lithium-ion battery (LIB) anodes due to their high specific capacity. Herein, the hierarchical structures of porous NiCo2O4 nanosheets directly grown on a conductive carbon cloth substrate (3D NCO-PSA/CC) were obtained by a facile in situ synthetic strategy. When applied as a binder-free LIB anode, it exhibited satisfactory performance with a high discharge capacity (a first discharge capacity of 2090.8 mA h g(-1) and a stable capacity of 1687.6 mA h g(-1) at 500 mA g(-1)), superior rate capacity (discharge capacity of 375.5 mA h g(-1) at 6000 mA g(-1)) and excellent reversibility (coulombic efficiency of approximately 100%). The outstanding performances should be attributed to the 3D porous structures, nanosheets and good conductivity of NCO-PSA/CC that could not only ensure the rapid transport of Li(+) ions and electrons but also remit the huge volume change during lithiation/delithiation processes. Undoubtedly, the present facile and effective strategy can be extended to other binary metal-oxide materials for use as high-performance energy storage and conversion devices.

  15. Performance evaluation and improvement directions for an Indian electric utility

    Energy Technology Data Exchange (ETDEWEB)

    Yadav, Vinod Kumar, E-mail: vinod@gbu.ac.in [Electrical Engineering Department, Gautam Buddha University, Greater Noida 201310 (India); Padhy, N.P.; Gupta, H.O. [Electrical Engineering Department, Indian Institute of Technology, Roorkee 247667 (India)

    2011-11-15

    This study evaluates the performance of 29 Electricity Distribution Divisions (EDDs) of an Indian state - Uttarakhand - deploying Input oriented Data Envelopment Analysis (DEA). The results indicate that the performance of several EDDs is sub-optimal, suggesting the potential for cost reductions and possible reduction in employees number. In the DEA method more than one unit are identified as efficient. Therefore, this study suggests a method for ranking the efficient units by their importance as benchmarks for the inefficient units through benchmark share measure. The bigger the benchmark share, the more important an efficient division is in benchmarking for inefficient ones. Result reveals that plain area divisions are relatively efficient and have higher potential to influence the performance of inefficient EDDs. This study is envisaged to be instrumental to policy makers and managers to increase the operational efficiency of inefficient EDDs and thereby increase the competitiveness in the face of restructuring and liberalization of Indian electricity sector. - Highlights: > Plain area divisions are more effective in integrating resources than hilly divisions. > For prevalent inefficiency two models are developed to varying environmental conditions. > Benchmark share identifies the variable that is influential in increasing the efficiency. > Savings in terms of reduction in O and M cost and number of Employees. > Findings of research work redefine the view point of the utility planners.

  16. High performance nickel-cadmium cells for electric vehicles

    Science.gov (United States)

    Cornu, Jean-Pierre

    A new concept of a cadmium electrode associated with a lighter nickel structure, a multi-cell module technology, allows the proposal of a very promisig alternative power source for electric vehicle (EV) batteries, the usable specific energy being 31% of the theoretical value. Every characteristic of this Ni-Cd module (i.e., specific energy and power, energy and power density, energy efficiency, life and reliability) gives the best performing EV battery, to date. Thus, with the efficient support of two major French car manufacturers and the French government, SAFT will launch, during Spring '95, the first pilot line of EV Ni-Cd module manufacturing.

  17. Estonian electricity supply scenarios for 2020 and their environmental performance

    Energy Technology Data Exchange (ETDEWEB)

    Koskela, Sirkka; Seppaelae, Jyri; Hiltunen, Marja-Riitta [Research Programme for Production and Consumption, Finnish Environment Institute, P.O. Box 140, 00251 Helsinki (Finland); Lipp, Ando; Pold, Evelin; Talve, Siret [CyclePlan Ltd, Akadeemia road 33, 12618 Tallinn (Estonia)

    2007-07-15

    Estonia is the only country in Europe with significant environmentally intensive oil shale-based energy production. However, the legal obligations of the EU will make substantial changes over the coming years to current electricity production technology. Increasing the use of alternative energy carriers for responding to future requirements has also been in focus. In this study, three different future electricity supply scenarios for Estonia in 2020 are considered and compared to the situation in 2002. They are based on domestic oil shale, imported natural gas, and imported nuclear power. According to the aims of the national energy policy, renewable energy sources were raised to 10% in all scenarios. Using the LCA methodology, the least damaging impact on the environment occurs in the 'nuclear scenario', with nuclear energy as the main energy source. The best scenario, however, depends on the weight or acceptance of accidental releases or other impacts not defined in this context. The 'Oil shale scenario' would be a slightly more damaging alternative than the 'Natural gas scenario' even if new technical solutions will remarkably improve the environmental performance of oil shale electricity production. Land use and waste disposal are crucial issues, particularly for oil shale and nuclear electricity production. However, the depletion of oil shale is not as critical an issue as the depletion of natural gas and uranium. According to the significance analysis of impact categories, climate change is the most significant impact on the environment in the scenarios. Future decisions on the development of the Estonian energy sector are most likely to be based on technological, economical and political aspects. Political aspects are likely to be the most significant. However, this type of study can give additional value to the discussion due to the increasing role of sustainability in energy issues. (author)

  18. Active control for performance enhancement of electrically controlled rotor

    Institute of Scientific and Technical Information of China (English)

    Lu Yang; Wang Chao

    2015-01-01

    Electrically controlled rotor (ECR) system has the potential to enhance the rotor perfor-mance by applying higher harmonic flap inputs. In order to explore the feasibility and effectiveness for ECR performance enhancement using closed-loop control method, firstly, an ECR rotor perfor-mance analysis model based on helicopter flight dynamic model is established, which can reflect the performance characteristics of ECR helicopter at high advance ratio. Based on the simulation platform, an active control method named adaptive T-matrix algorithm is adopted to explore the feasibility and effectiveness for ECR performance enhancement. The simulation results verify the effectiveness of this closed-loop control method. For the sample ECR helicopter, about 3%rotor power reduction is obtained with the optimum 2/rev flap inputs at the advance ratio of 0.34. And through analyzing the distributions of attack of angle and drag in rotor disk, the underlying physical essence of ECR power reduction is cleared. Furthermore, the influence of the key control parameters, including convergence factor and weighting matrix, on the effectiveness of closed-loop control for ECR performance enhancement is explored. Some useful results are summarized, which can be used to direct the future active control law design of ECR performance enhancement.

  19. Robust Slippery Coating with Superior Corrosion Resistance and Anti-Icing Performance for AZ31B Mg Alloy Protection.

    Science.gov (United States)

    Zhang, Jialei; Gu, Changdong; Tu, Jiangping

    2017-03-29

    Biomimetic slippery liquid-infused porous surfaces (SLIPSs) are developed as a potential alternative to superhydrophobic surfaces (SHSs) to resolve the issues of poor durability in corrosion protection and susceptibility to frosting. Herein, we fabricated a double-layered SLIPS coating on the AZ31 Mg alloy for corrosion protection and anti-icing application. The porous top layer was infused by lubricant, and the compact underlayer was utilized as a corrosion barrier. The water-repellent SLIPS coating exhibits a small sliding angle and durable corrosion resistance compared with the SHS coating. Moreover, the SLIPS coating delivers durable anti-icing performance for the Mg alloy substrate, which is obviously superior to the SHS coating. Multiple barriers in the SLIPS coating, including the infused water-repellent lubricant, the self-assembled monolayers coated porous top layer, and the compact layered double hydroxide-carbonate composite underlayer, are suggested as being responsible for the enhanced corrosion resistance and anti-icing performance. The robust double-layered SLIPS coating should be of great importance to expanding the potential applications of light metals and their alloys.

  20. Unlocking the Origin of Superior Performance of a Si-Ge Core-Shell Nanowire Quantum Dot Field Effect Transistor.

    Science.gov (United States)

    Dhungana, Kamal B; Jaishi, Meghnath; Pati, Ranjit

    2016-07-13

    The sustained advancement in semiconducting core-shell nanowire technology has unlocked a tantalizing route for making next generation field effect transistor (FET). Understanding how to control carrier mobility of these nanowire channels by applying a gate field is the key to developing a high performance FET. Herein, we have identified the switching mechanism responsible for the superior performance of a Si-Ge core-shell nanowire quantum dot FET over its homogeneous Si counterpart. A quantum transport approach is used to investigate the gate-field modulated switching behavior in electronic current for ultranarrow Si and Si-Ge core-shell nanowire quantum dot FETs. Our calculations reveal that for the ON state, the gate-field induced transverse localization of the wave function restricts the carrier transport to the outer (shell) layer with the pz orbitals providing the pathway for tunneling of electrons in the channels. The higher ON state current in the Si-Ge core-shell nanowire FET is attributed to the pz orbitals that are distributed over the entire channel; in the case of Si nanowire, the participating pz orbital is restricted to a few Si atoms in the channel resulting in a smaller tunneling current. Within the gate bias range considered here, the transconductance is found to be substantially higher in the case of a Si-Ge core-shell nanowire FET than in a Si nanowire FET, which suggests a much higher mobility in the Si-Ge nanowire device.

  1. SEPS comet rendezvous performance assessment. [Solar Electric Propulsion System

    Science.gov (United States)

    Sauer, C. G., Jr.

    1980-01-01

    This paper presents an assessment of delivered payload capability for a number of selected rendezvous missions to periodic comets with launch opportunities through the years 1986-1996. These missions are chosen using a selection criteria that considers both expected scientific interest and earth-based sighting considerations. Some 22 mission opportunities are found that satisfies the selection criteria. Spacecraft performance is presented for each mission opportunity based on use of a space shuttle, a twin stage inertial-upper-stage, and a conceptual solar-electric-propulsion-system with a nominal rendezvous 50 days before comet perihelion. Additional trajectory and propulsion enhancements are investigated for several comet rendezvous missions in order to improve spacecraft performance. An indirect transfer trajectory for an Encke mission is shown to offer substantial delivered payload. In addition the use of concentrator solar arrays is considered for several of the more interesting comet missions.

  2. Performance monitoring of electric shovels digging oil sands

    Energy Technology Data Exchange (ETDEWEB)

    Patnayak, S. [Alberta Univ., Edmonton, AB (Canada). Natural Resources Engineering Facility; Tannant, D.D. [Alberta Univ., Edmonton, AB (Canada). School of Mining and Petroleum Engineering; Parsons, I. [Syncrude Canada Ltd., Edmonton, AB (Canada). Edmonton Research Centre; Del Valle, V. [Syncrude Canada Ltd., Fort McMurray, AB (Canada)

    2005-07-01

    Some of the largest available mining equipment is used for oil sand mining operations. However, the performance of electric cable shovels varies with the diggability characteristics of the ground. In particular, oil sands diggability with cable shovels depends on structural geology, the depositional environment and geotechnical parameters. This paper described some of the key shovel performance indicators such as dig cycle time, digging energy and digging power. In winter, frost penetration can also affect oil sands diggability. The challenge of hard digging in oil sands is often addressed by blasting or ripping, which increases the cost of production and impedes productivity. The shovel performance is also influenced by other parameters such as operator skills, bucket and tooth design and shovel dipper trajectory. This paper demonstrated that hoist and crowd motor voltages and currents are useful in identifying the beginning and end of dig cycles. Performance indicators such as dig cycle time, hoist motor energy and power, and crowd motor energy and power were considered to assess material diggability. It was suggested that hoist power represents the ground diggability better than other performance indicators. 5 refs., 1 tab., 10 figs.

  3. 30 CFR 75.523-2 - Deenergization of self-propelled electric face equipment; performance requirements.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Deenergization of self-propelled electric face... Electrical Equipment-General § 75.523-2 Deenergization of self-propelled electric face equipment; performance requirements. (a) Deenergization of the tramming motors of self-propelled electric face equipment, required...

  4. Development of high performance nano-porous polyethersulfone ultrafiltration membranes with hydrophilic surface and superior antifouling properties

    Energy Technology Data Exchange (ETDEWEB)

    Rahimpour, Ahmad, E-mail: ahmadrahimpour@yahoo.com [Nanobiotechnology Research Laboratory, Faculty of Chemical Engineering, Babol University of Technology, Babol (Iran, Islamic Republic of); Madaeni, Sayed Siavash [Membrane Research Center, Department of Chemical Engineering, Razi University, Kermanshah (Iran, Islamic Republic of); Jahanshahi, Mohsen [Nanobiotechnology Research Laboratory, Faculty of Chemical Engineering, Babol University of Technology, Babol (Iran, Islamic Republic of); Mansourpanah, Yaghoub [Department of Chemistry, Faculty of Science, Lorestan University, Khorramabad (Iran, Islamic Republic of); Mortazavian, Narmin [Nanobiotechnology Research Laboratory, Faculty of Chemical Engineering, Babol University of Technology, Babol (Iran, Islamic Republic of)

    2009-08-30

    Hydrophilic nano-porous polyethersulfone ultrafiltration membranes were developed for milk concentration. The membranes were prepared from new dope solution containing polyethersulfone (PES)/polyvinylpirrolidone (PVP)/polyethyleneglycole (PEG)/cellulose acetate phthalate (CAP)/acrylic acid/Triton X-100 using phase inversion induced by immersion precipitation technique. This casting solution leads to formation of new hydrophilic membranes. The morphological studies were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). In addition, the hydrophilicity and performance of membranes were examined by contact angel measurements and cross-flow filtration (pure water flux, milk water permeation, protein rejection and antifouling measurements). The contact angle measurements indicate that a surface with superior hydrophilicity was obtained for PES membranes. Two concentrations of PES (16 and 14.4 wt.%) and two different non-solvents (pure water and mixtures of water and IPA) were used for preparation of membranes. The morphological studies showed that the higher concentration of PES and the presence of IPA in the gelation media results in formation of a membrane with a dense top and sub-layer with small pores on the surface. The pure water flux of membranes was decreased when higher polymer concentration and mixtures of water and IPA were employed for membrane formation. On the other hand, the milk water permeation and protein rejection were increased using mixtures of water and IPA as non-solvent. Furthermore, the fouling analysis of the membranes demonstrated that the membrane surface with fewer tendencies for fouling was obtained.

  5. Silicon carbide against silicon: a comparison in terms of physical properties, technology and electrical performance of power devices

    OpenAIRE

    Locatelli, M.; Gamal, S.,

    1993-01-01

    The aim of the present paper is to give the state of the art of the silicon carbide technology by “photographing” it beside the unique technology used for power electronics that is the silicon one. The theoretical superiority of SiC physical properties on those of Si, together with the important technological advancements realized during the last decade, are the main reasons of the interest given to SiC nowadays. Concerning electrical performance, the voltage and power handling capabilities d...

  6. Performance assessment of the PNM Prosperity electricity storage project

    Energy Technology Data Exchange (ETDEWEB)

    Roberson, Dakota [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ellison, James F. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bhatnagar, Dhruv [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Schoenwald, David A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-05-01

    The purpose of this study is to characterize the technical performance of the PNM Prosperity electricity storage project, and to identify lessons learned that can be used to improve similar projects in the future. The PNM Prosperity electricity storage project consists of a 500 kW/350 kWh advanced lead-acid battery with integrated supercapacitor (for energy smoothing) and a 250 kW/1 MWh advanced lead-acid battery (for energy shifting), and is co-located with a 500 kW solar photovoltaic (PV) resource. The project received American Reinvestment and Recovery Act (ARRA) funding. The smoothing system is e ective in smoothing intermittent PV output. The shifting system exhibits good round-trip efficiencies, though the AC-to-AC annual average efficiency is lower than one might hope. Given the current utilization of the smoothing system, there is an opportunity to incorporate additional control algorithms in order to increase the value of the energy storage system.

  7. Performance assessment of the PNM Prosperity electricity storage project :

    Energy Technology Data Exchange (ETDEWEB)

    Roberson, Dakota; Ellison, James F.; Bhatnagar, Dhruv; Schoenwald, David A.

    2014-05-01

    The purpose of this study is to characterize the technical performance of the PNM Prosperity electricity storage project, and to identify lessons learned that can be used to improve similar projects in the future. The PNM Prosperity electricity storage project consists of a 500 kW/350 kWh advanced lead-acid battery with integrated supercapacitor (for energy smoothing) and a 250 kW/1 MWh advanced lead-acid battery (for energy shifting), and is co-located with a 500 kW solar photovoltaic (PV) resource. The project received American Reinvestment and Recovery Act (ARRA) funding. The smoothing system is e ective in smoothing intermittent PV output. The shifting system exhibits good round-trip efficiencies, though the AC-to-AC annual average efficiency is lower than one might hope. Given the current utilization of the smoothing system, there is an opportunity to incorporate additional control algorithms in order to increase the value of the energy storage system.

  8. Performance of International Space Station Alpha electric power systems

    Energy Technology Data Exchange (ETDEWEB)

    Hill, R.; Lu, C.Y.; Padhye, V.; Hajela, G.; Hague, L. [Rockwell International, Canoga Park, CA (United States). Rocketdyne Division

    1995-12-31

    The International Space Station Alpha (ISSA) will be an Earth-orbiting laboratory in space. It will house experimental payloads, distribute resource utilities, and support human habitation for conducting research and science experiments in a microgravity environment. Electrical power is a major utility to support successful achievement of the mission goal. The ISSA United States On-Orbit Segment (USOS) Electric Power System (EPS) power generation capability will vary with orbital parameters, natural and induced environment, and hardware aging/replacement throughout the ISSA life. Power capability will be further restricted by various assembly configurations during ISSA buildup, by various flight attitudes, by shadowing on the solar arrays, by EPS operational constraints, such as pointing accuracy, battery charging, as well as operating voltage setpoints, and by ISSA operational constraints either to avoid long-term solar array shadowing from the adjacent solar array or to accommodate ISSA maneuver during proximity operations with other space vehicles, mating, and departing. Design of the ISSA USOS EPS takes into consideration the various equipment degradation modes, operation constraints, and orbital conditions to make it compatible with the environments and to meet power, lifetime, and performance requirements.

  9. Performance requirements of automotive batteries for future car electrical systems

    Science.gov (United States)

    Friedrich, R.; Richter, G.

    The further increase in the number of power-consuming functions which has been announced for future vehicle electrical systems, and in particular the effects of new starting systems on battery performance, requires a further optimization of the lead acid system coupled with effective energy management, and enhanced battery operating conditions. In the face of these increased requirements, there are proven benefits to splitting the functions of a single SLI battery between two separate, special-purpose batteries, each of which are optimized, for high power output and for high energy throughput, respectively. This will bring about a marked improvement in weight, reliability, and state of charge (SOC). The development of special design starter and service batteries is almost completed and will lead to new products with a high standard of reliability. The design of the power-optimized lead acid accumulator is particularly suitable for further development as the battery for a 42/36 V electrical system. This is intended to improve the efficiency of the generator and the various power-consuming functions and to improve start/stop operation thereby bringing about a marked reduction in the fuel consumption of passenger cars. This improvement can also be assisted by a charge management system used in conjunction with battery status monitoring.

  10. Performance evaluation of a transformerless multiphase electric submersible pump system

    Directory of Open Access Journals (Sweden)

    Ahmed A. Hakeem

    2014-08-01

    Full Text Available Using of low-voltage variable-frequency drive followed by a step-up transformer is the most preferable way to feed an electrical submersible pump motor. The existence of long feeder between the motor and drive systems usually causes over-voltage problems because of the travelling wave phenomenon, which makes the employment of filter networks on the motor or inverter terminals mandatory. The so-called boost-inverter inherently can solve this problem with filter-less operation as it offers a direct sinusoidal output voltage. As boost inverters have voltage boosting capability, it can provide a transformer-less operation as well. This study investigates the performance of a five-phase modular winding induction machine fed from a boost-inverter through a long feeder. A simulation study using a 1000 Hp system and experimental investigation on a 1 Hp prototype machine are used to support the presented approach.

  11. Submerged arc furnace process superior to the Waelz process in reducing PCDD/F emission during thermal treatment of electric arc furnace dust.

    Science.gov (United States)

    Xu, Fu-Qian; Huang, Shao-Bin; Liao, Wei-Tung; Wang, Lin-Chi; Chang, Yu-Cheng; Chang-Chien, Guo-Ping

    2014-01-01

    Besides the Waelz process, the submerged arc furnace (SAF) process has also been extensively used to retain metals from ashes and scraps in the metallurgical industry. However, very little is known about the formation and depletion of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from this thermal process. In this study, an electric arc furnace (EAF) dust treatment plant adopting the SAF process was investigated and compared to the plant adopting the Waelz process. The predominant contributor of PCDD/F I-TEQ input was the EAF dusts, accounting for 98.4% of the total. The PCDD/F contents in the generated fly ashes of the SAF were extremely low, as almost all the organic compounds for PCDD/F formation were decomposed by the high operating temperatures (1500-1700 °C) of the SAF. Therefore, the PCDD/F emission factor of the SAF process (46.9 μg I-TEQ/tonne-EAF dust) was significantly lower than that of the Waelz process (840-1120 μg I-TEQ/tonne-EAF dust). Its PCDD/F output/input ratios (0.23 and 0.50 based on mass and toxicity) were also lower than those of the Waelz process plant (0.62 and 1.19). Therefore, the SAF process is superior to the Waelz process in reducing the potential of PCDD/F formation.

  12. Comercio Electrónico y Educación Superior: Consideraciones sobre el Cómo y el Cuándo

    Directory of Open Access Journals (Sweden)

    Victoria E. Erosa

    2000-01-01

    Full Text Available El dinamismo de la Tecnología de la Información está ocasionando el surgimiento de una nueva era en la cual los cambios en el ambiente han conducido a nuevos modelos de negocios ejerciendo presión sobre las instituciones educativas para formar profesionistas, técnicos y directivos capaces de enfrentar este reto. Una investigación de naturaleza exploratoria sobre la evolución del Comercio Electrónico en distintos sectores empresariales de México, sirve como referencia para plantear algunas consideraciones que podrían resultar de utilidad al diseñar e instrumentar programas de educación superior en esta materia. Los resultados que se presentan muestran evidencias de la necesidad de instrumentar programas de estudio, a diversos niveles, orientados a la formación y consolidación de una cultura organizacional que favorezca la adaptación al nuevo ambiente tecnológico, y al desarrollo de habilidades directivas y operativas para administrar la cadena de valor en este ambiente. La investigación sugiere que se precisa una rápida respuesta del ámbito educativo, consistente con la velocidad del cambio tecnológico.

  13. Desempenho agronômico das videiras 'Crimson Seedless' e 'Superior Seedless' no norte de Minas Gerais Agronomic performance of 'Crimson Seedless' and 'Superior Seedless' vines in the north region of Minas Gerais

    Directory of Open Access Journals (Sweden)

    Nelson Pires Feldberg

    2007-06-01

    Full Text Available O objetivo deste trabalho foi avaliar a influência do vigor dos porta-enxertos '1103 Paulsen' e 'IAC-572 Jales', no desempenho agronômico das cultivares Crimson Seedless e Superior Seedless. O experimento foi realizado na Fazenda Experimental da Epamig, em Mocambinho, distrito de Jaíba, MG, em delineamento inteiramente casualizado com sete repetições em esquema fatorial 2x2. Foram analisadas a fertilidade de gemas, o número e a massa de cachos e a massa de ramos. O porta-enxerto '1103 Paulsen' proporcionou os melhores resultados nas cultivares Crimson Seedless e Superior Seedless quanto à massa e número de cachos por planta e fertilidade de gemas, com produtividade média de 31,9 e 22,4 t ha-1 ano-1 , respectivamente. O porta-enxerto 'IAC-572 Jales' proporcionou maior vigor, com maior massa de ramos por planta nas duas cultivares. O porta-enxerto '1103 Paulsen' induziu a maiores fertilidade de gemas e produtividades em 'Crimson Seedless' e 'Superior Seedless' e pode ser indicado para o cultivo na região de Jaíba, MG.The objective of this work was to study the influence of the '1103 Paulsen' and 'IAC-572 Jales' rootstocks vigor in the agronomic performance of the cultivars 'Crimson Seedless' and 'Superior Seedless'. The experiment was carried in the Epamig Experimental Farm located in Mocambinho, Jaíba, MG, Brazil, in completely randomized experimental design with seven replications in factorial 2x2. The following variables were studied: bud fertility, number and weight of clusters and cane weight. The '1103 Paulsen' rootstock showed better results for cultivars 'Crimson Seedless' and 'Superior Seedless' regarding the number of clusters and their weight by plant and bud fertility, with average productivity of 31.9 and 22.4 t ha-1 year-1 , respectively. The 'IAC-572 Jales' rootstock provided higher vigor, comprising greater weight of canes per plant in both cultivars. The '1103 Paulsen' rootstock induced higher bud fertility and

  14. One-step synthesis of hierarchically porous carbons for high-performance electric double layer supercapacitors

    Science.gov (United States)

    Zhang, Haitao; Zhang, Lei; Chen, Jun; Su, Hai; Liu, Fangyan; Yang, Weiqing

    2016-05-01

    With plenty of unique porous structure at micro-/nano scale, hierarchically porous carbons (HPCs) are promising for usage in advanced electric double layer supercapacitors (EDLCs) as the electrode materials. However, wide-range adoption of HPC for practical application is largely shadowed by its extremely complex synthesis process with considerably low production efficiency. Herein we reported a simple template-free, one-step sintering method, to massively produce the HPCs for high-performance EDLCs. Resorting to the 3D structure modification of the wide pore size distribution, high surface area of HPCs (up to 3000 m2 g-1) was achieved. By using 1 M Na2SO4 as electrolyte, the as-fabricated HPCs based EDLCs can be operated reversibly over a wide voltage window of 1.6 V with superior specific capacitance of 240 F g-1 under a current density of 0.5 A g-1. In the meanwhile, the EDLCs exhibit excellent rate capability (high power density of 16 kW kg-1 at 10.2 Wh kg-1) and long-term cycling stability with 9% loss of its initial capacitance after 2000 cycles. This output performance distinguished itself among most of the carbon-based EDLCs with neutral aqueous electrolyte. Thus, the template-free one-step sintering method produced HPCs for EDLCs represents a new approach for high-performance energy storage.

  15. Technical performance indicators of electric power generation service; Indicadores de desempenho tecnico dos servicos de geracao

    Energy Technology Data Exchange (ETDEWEB)

    Amaral, Cristiano Abijao de; Carvalho, Fabiano da Rosa; Nascimento, Jose Guilherme A. do; Feijao, Romulo de Vasconcelos [Agencia Nacional de Energia Eletrica (ANEEL), Brasilia, DF (Brazil)

    1999-07-01

    The aim of this work is to present the preliminary indicators of the technical performance from the Brazilian electric power generation services. The indicators represent essentially the reliability, the availability and the assistance to dispatch and they are calculated in three aggregation levels: power generation unit, electric power plant and electric utilities. In this context is considered the difference among several technologies used to generate electric power, the several kinds of electric power systems, and the several categories of agents' generators.

  16. 3D Polyaniline Architecture by Concurrent Inorganic and Organic Acid Doping for Superior and Robust High Rate Supercapacitor Performance.

    Science.gov (United States)

    Gawli, Yogesh; Banerjee, Abhik; Dhakras, Dipti; Deo, Meenal; Bulani, Dinesh; Wadgaonkar, Prakash; Shelke, Manjusha; Ogale, Satishchandra

    2016-02-12

    A good high rate supercapacitor performance requires a fine control of morphological (surface area and pore size distribution) and electrical properties of the electrode materials. Polyaniline (PANI) is an interesting material in supercapacitor context because it stores energy Faradaically. However in conventional inorganic (e.g. HCl) acid doping, the conductivity is high but the morphological features are undesirable. On the other hand, in weak organic acid (e.g. phytic acid) doping, interesting and desirable 3D connected morphological features are attained but the conductivity is poorer. Here the synergy of the positive quality factors of these two acid doping approaches is realized by concurrent and optimized strong-inorganic (HCl) and weak-organic (phytic) acid doping, resulting in a molecular composite material that renders impressive and robust supercapacitor performance. Thus, a nearly constant high specific capacitance of 350 F g(-1) is realized for the optimised case of binary doping over the entire range of 1 A g(-1) to 40 A g(-1) with stability of 500 cycles at 40 A g(-1). Frequency dependant conductivity measurements show that the optimized co-doped case is more metallic than separately doped materials. This transport property emanates from the unique 3D single molecular character of such system.

  17. 3D Polyaniline Architecture by Concurrent Inorganic and Organic Acid Doping for Superior and Robust High Rate Supercapacitor Performance

    Science.gov (United States)

    Gawli, Yogesh; Banerjee, Abhik; Dhakras, Dipti; Deo, Meenal; Bulani, Dinesh; Wadgaonkar, Prakash; Shelke, Manjusha; Ogale, Satishchandra

    2016-02-01

    A good high rate supercapacitor performance requires a fine control of morphological (surface area and pore size distribution) and electrical properties of the electrode materials. Polyaniline (PANI) is an interesting material in supercapacitor context because it stores energy Faradaically. However in conventional inorganic (e.g. HCl) acid doping, the conductivity is high but the morphological features are undesirable. On the other hand, in weak organic acid (e.g. phytic acid) doping, interesting and desirable 3D connected morphological features are attained but the conductivity is poorer. Here the synergy of the positive quality factors of these two acid doping approaches is realized by concurrent and optimized strong-inorganic (HCl) and weak-organic (phytic) acid doping, resulting in a molecular composite material that renders impressive and robust supercapacitor performance. Thus, a nearly constant high specific capacitance of 350 F g‑1 is realized for the optimised case of binary doping over the entire range of 1 A g‑1 to 40 A g‑1 with stability of 500 cycles at 40 A g‑1. Frequency dependant conductivity measurements show that the optimized co-doped case is more metallic than separately doped materials. This transport property emanates from the unique 3D single molecular character of such system.

  18. Covalently coupled hybrid of graphitic carbon nitride with reduced graphene oxide as a superior performance lithium-ion battery anode.

    Science.gov (United States)

    Fu, Yongsheng; Zhu, Junwu; Hu, Chong; Wu, Xiaodong; Wang, Xin

    2014-11-01

    An in situ chemical synthetic approach has been designed for the fabrication of a covalently coupled hybrid consisting of graphitic carbon nitride (g-C3N4) with reduced graphene oxide (rGO) with differing g-C3N4/rGO ratio. The epoxy groups of graphene oxide (GO) undergo a nucleophilic substitution reaction with dicyandiamide (C2H4N4) to form the C2H4N4-GO composite via a covalent C-N bond, and then both the in situ polymerization of C2H4N4 and the thermal reduction of GO can be achieved at higher temperatures, forming the covalently coupled g-C3N4-rGO. FT-IR, CP-MAS NMR and XPS analyses, clearly revealed a covalent interaction between the g-C3N4 and rGO sheets. The g-C3N4-rGO exhibits an unprecedented high, stable and reversible capacity of 1525 mA h g(-1) at a current density of 100 mA g(-1) after 50 cycles. Even at a large current density of 1000 mA g(-1), a reversible capacity of 943 mA h g(-1) can still be retained. The superior electrochemical performance of g-C3N4-rGO is attributed to the specific characteristics of the unique nanostructure of g-C3N4-rGO and the concerted effects of g-C3N4 and rGO, including covalent interactions between the two moieties, the good conductivity and high special surface area of the nanocomposite, as well as the template effect of the planar amino group of g-C3N4 for the dispersed decoration of Li(+) ions.

  19. Tribological performance of polymer composites used in electrical engineering applications

    Indian Academy of Sciences (India)

    Zafer Demir

    2013-04-01

    Sliding wear performance of 20% mica-filled polyamide 6 (PA6 + 20% mica) and 20% short glass fibrereinforced polysulphone (PSU + 20 GFR) polymer composites used in electrical applications were investigated using a pin-on-disc wear test apparatus. Two different disc materials were used in this study. These are AISI 316 L stainless steel and 30% glass fibre-reinforced polyphenylenesulphide (PPS + 30%GFR) polymer composite. Wear test was carried out at 10, 20 and 30 N applied load values and 0.5 m/s sliding speed and at ambient temperature and humidity. Different combinations of rubbing surfaces were examined and friction coefficient and specific wear rate values were obtained and compared. For two material combinations used in this investigation, the coefficient of friction shows insignificant sensitivity to applied load values and large sensitivity to material combinations. For specific wear rate, PA6 + 20% mica composite has shown insensitivity to change in load, speed and materials combination while PSU + 20% glass fibre composite has shown high sensitivity to the change in load and material combinations. The friction coefficient of PA6 + 20% mica and PSU + 20 glass fibre rubbing against the AISI 4140 steel disc is between 0.35 and 0.40. In rubbing against PPS + 30% glass fibre their values were between 0.25 and 0.30. Specific wear rate for PA6 + 20% mica and PSU + 20% glass fibre composites are in the order of 10-13 to 10-14 m2/N. Finally, the wear mechanisms are a combination of adhesive and abrasive wear processes. In terms of application, especially in electrical systems, a substantial contribution was provided to extend switch life. Thus, besides robustness, this also ensured safety for the system and the users against undesirable situations.

  20. Thrust stand for vertically oriented electric propulsion performance evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, Trevor [University of Tennessee Space Institute, Tullahoma, Tennessee 37388 (United States); Polzin, Kurt A. [NASA, Marshall Space Flight Center, Huntsville, Alabama 35812 (United States)

    2010-11-15

    A variation of a hanging pendulum thrust stand capable of measuring the performance of an electric thruster operating in the vertical orientation is presented. The vertical orientation of the thruster dictates that the thruster must be horizontally offset from the pendulum pivot arm, necessitating the use of a counterweight system to provide a neutrally stable system. Motion of the pendulum arm is transferred through a balance mechanism to a secondary arm on which deflection is measured. A noncontact light-based transducer is used to measure displacement of the secondary beam. The members experience very little friction, rotating on twisting torsional pivots with oscillatory motion attenuated by a passive, eddy-current damper. Displacement is calibrated using an in situ thrust calibration system. Thermal management and self-leveling systems are incorporated to mitigate thermal and mechanical drifts. Gravitational force and torsional spring constants associated with flexure pivots provide restoring moments. An analysis of the design indicates that the thrust measurement range spans roughly four decades, with the stand capable of measuring thrust up to 12 N for a 200 kg thruster and up to approximately 800 mN for a 10 kg thruster. Data obtained from calibration tests performed using a 26.8 lbm simulated thruster indicated a resolution of 1 mN on 100 mN level thrusts, while those tests conducted on a 200 lbm thruster yielded a resolution of roughly 2.5 mN at thrust levels of 0.5 N and greater.

  1. Thrust Stand for Vertically Oriented Electric Propulsion Performance Evaluation

    Science.gov (United States)

    Moeller, Trevor; Polzin, Kurt A.

    2010-01-01

    A variation of a hanging pendulum thrust stand capable of measuring the performance of an electric thruster operating in the vertical orientation is presented. The vertical orientation of the thruster dictates that the thruster must be horizontally offset from the pendulum pivot arm, necessitating the use of a counterweight system to provide a neutrally-stable system. Motion of the pendulum arm is transferred through a balance mechanism to a secondary arm on which deflection is measured. A non-contact light-based transducer is used to measure displacement of the secondary beam. The members experience very little friction, rotating on twisting torsional pivots with oscillatory motion attenuated by a passive, eddy current damper. Displacement is calibrated using an in situ thrust calibration system. Thermal management and self-leveling systems are incorporated to mitigate thermal and mechanical drifts. Gravitational restoring force and torsional spring constants associated with flexure pivots provide restoring moments. An analysis of the design indicates that the thrust measurement range spans roughly four decades, with the stand capable of measuring thrust up to 12 N for a 200 kg thruster and up to approximately 800 mN for a 10 kg thruster. Data obtained from calibration tests performed using a 26.8 lbm simulated thruster indicated a resolution of 1 mN on 100 mN-level thrusts, while those tests conducted on 200 lbm thruster yielded a resolution of roughly 2.5 micro at thrust levels of 0.5 N and greater.

  2. Thrust stand for vertically oriented electric propulsion performance evaluation.

    Science.gov (United States)

    Moeller, Trevor; Polzin, Kurt A

    2010-11-01

    A variation of a hanging pendulum thrust stand capable of measuring the performance of an electric thruster operating in the vertical orientation is presented. The vertical orientation of the thruster dictates that the thruster must be horizontally offset from the pendulum pivot arm, necessitating the use of a counterweight system to provide a neutrally stable system. Motion of the pendulum arm is transferred through a balance mechanism to a secondary arm on which deflection is measured. A noncontact light-based transducer is used to measure displacement of the secondary beam. The members experience very little friction, rotating on twisting torsional pivots with oscillatory motion attenuated by a passive, eddy-current damper. Displacement is calibrated using an in situ thrust calibration system. Thermal management and self-leveling systems are incorporated to mitigate thermal and mechanical drifts. Gravitational force and torsional spring constants associated with flexure pivots provide restoring moments. An analysis of the design indicates that the thrust measurement range spans roughly four decades, with the stand capable of measuring thrust up to 12 N for a 200 kg thruster and up to approximately 800 mN for a 10 kg thruster. Data obtained from calibration tests performed using a 26.8 lbm simulated thruster indicated a resolution of 1 mN on 100 mN level thrusts, while those tests conducted on a 200 lbm thruster yielded a resolution of roughly 2.5 mN at thrust levels of 0.5 N and greater.

  3. Grain Refinement and High-Performance of Equal-Channel Angular Pressed Cu-Mg Alloy for Electrical Contact Wire

    Directory of Open Access Journals (Sweden)

    Aibin Ma

    2014-12-01

    Full Text Available Multi-pass equal-channel angular pressing (EACP was applied to produce ultrafine-grained (UFG Cu-0.2wt%Mg alloy contact wire with high mechanical/electric performance, aim to overcome the catenary barrier of high-speed trains by maximizing the tension and improving the power delivery. Microstructure evolution and overall properties of the Cu-Mg alloy after different severe-plastic-deformation (SPD routes were investigated by microscopic observation, tensile and electric tests. The results show that the Cu-Mg alloy after multi-pass ECAP at 473 K obtains ultrafine grains, higher strength and desired conductivity. More passes of ECAP leads to finer grains and higher strength, but increasing ECAP temperature significantly lower the strength increment of the UFG alloy. Grain refinement via continuous SPD processing can endow the Cu-Mg alloy superior strength and good conductivity characteristics, which are advantageous to high-speed electrification railway systems.

  4. Efficient Transfer of Graphene-Physical and Electrical Performance Perspective

    KAUST Repository

    Ghoneim, Mohamed T.

    2012-11-01

    Efficient Transfer of Graphene –Physical and Electrical Performance Perspective Graphene has become one of the most widely used atomic crystal structure materials since its first experimental proof by Geim-Novoselov in 2004 [1]. This is attributed to its reported incredible carrier mobility, mechanical strength and thermal conductivity [2] [3] [4]. These properties suggest interesting applications of Graphene ranging from electronics to energy storage and conversion [5]. In 2008, Chen et al reported a 40,000 cm2V-1s-1 mobility for a Single Layer Graphene (SLG) on SiO2 compared to 285 cm2V-1s-1 for silicon channel devices [6]. Chemical vapor deposition (CVD) is a common method for growing graphene on a metal surface as a catalyst for graphene nucleation. This adds a necessary transfer step to the target substrate ultimately desired for graphene devices fabrication. Interfacing with graphene is a critical challenge in preserving its promising high mobility. This initiated the motivation for studying the effect of intermediate interfaces imposed by transfer processes. In this work, few layers graphene (FLG) was grown on copper foils inside a high temperature furnace. Then Raman spectroscopy was performed on grown graphene sample to confirm few (in between 3-10) layers. Afterwards the sample was cut into three pieces and transferred to 300 nm SiO2 on Si substrates using three techniques, namely: (i) pickup transfer with top side of Graphene brought in contact with SiO2 [7], (ii) Ploy (methyl methacrylate) (PMMA) transfer with Graphene and a PMMA support layer on top scooped from bottom side [8], and (iii) a modified direct transfer which is similar to PMMA transfer without the support layer [9]. Comparisons were done using Raman spectroscopy to determine the relative defectivity, Scanning Electron Microscopy (SEM) to observe discontinuities and Atomic Force Microscopy (AFM) to measure surface roughness. Then we conclude with electrical data based on the contact

  5. Constructing nanoporous carbon nanotubes/Bi2Te3 composite for synchronous regulation of the electrical and thermal performances

    Science.gov (United States)

    Zhang, Qihao; Xu, Leilei; Zhou, Zhenxing; Wang, Lianjun; Jiang, Wan; Chen, Lidong

    2017-02-01

    Porous nanograined thermoelectric materials exhibit low thermal conductivity due to scattering of phonons by pores, which are favorable for thermoelectric applications. However, the benefit is not large enough to overcome the deficiency in the electrical performance. Herein, an approach is presented to reduce the thermal conductivity and synchronously enhance the electrical conductivity through constructing a nanoporous thermoelectric composite. Carbon nanotubes (CNTs) are truncated and homogeneously dispersed within the Bi2Te3 matrix by a cryogenic grinding (CG) technique for the first time, which efficiently suppress the Bi2Te3 grain growth and create nanopores with the size ranging from dozens to hundreds of nanometers. The lattice thermal conductivity is substantially decreased by broad wavelength phonon scattering resulting from nanopores, increased grain boundaries, and newly formed interfaces. Meanwhile, the electrical conductivity is improved due to the enhanced carrier mobility, which may originate from the bridging effect between the Bi2Te3 grains and CNTs. The maximum ZT is improved by almost a factor of 2 due to the simultaneous optimization of electrical and thermal performances. Our study demonstrates the superiority of constructing a bulk thermoelectric composite with nanopores by the uniform dispersion of CNTs through a CG technique for enhanced thermoelectric properties, which provides a wider approach to thermoelectric nanostructure engineering.

  6. 76 FR 3517 - Standards of Performance for Fossil-Fuel-Fired, Electric Utility, Industrial-Commercial...

    Science.gov (United States)

    2011-01-20

    ... AGENCY 40 CFR Part 60 RIN 2060-AQ46 Standards of Performance for Fossil-Fuel-Fired, Electric Utility... limited to, the following: Category NAICS \\1\\ Examples of regulated entities Industry 221112 Fossil fuel-fired electric utility steam generating units. Federal Government 22112 Fossil fuel-fired electric...

  7. 76 FR 3587 - Standards of Performance for Fossil-Fuel-Fired, Electric Utility, Industrial-Commercial...

    Science.gov (United States)

    2011-01-20

    ... AGENCY 40 CFR Part 60 RIN 2060-AQ46 Standards of Performance for Fossil-Fuel-Fired, Electric Utility... 221112 Fossil fuel-fired electric utility steam generating units. Federal Government 22112 Fossil fuel... government 22112 Fossil fuel-fired electric utility steam generating units owned by municipalities. 921150...

  8. Energy Consumption Performance Analysis of Electrical Mitad at ...

    African Journals Online (AJOL)

    Bheema

    Keywords: Electrical mitad, Injera baking energy, Thermal efficiency, Baking temperature, ... 2011; Awet, 2011) have also studied the thermal conductivity of the clay .... heat for heating-up of the batter from room temperature to water boiling ...

  9. Comparison performance of split plug-in hybrid electric vehicle and hybrid electric vehicle using ADVISOR

    Directory of Open Access Journals (Sweden)

    Mohd Rashid Muhammad Ikram

    2017-01-01

    Full Text Available Electric vehicle suffers from relatively short range and long charging times and consequently has not become an acceptable solution to the automotive consumer. The addition of an internal combustion engine to extend the range of the electric vehicle is one method of exploiting the high efficiency and lack of emissions of the electric vehicle while retaining the range and convenient refuelling times of a conventional gasoline powered vehicle. The term that describes this type of vehicle is a hybrid electric vehicle. Many configurations of hybrid electric vehicles have been designed and implemented, namely the series, parallel and power-split configurations. This paper discusses the comparison between Split Plug-in Hybrid Electric Vehicle(SPHEV and Hybrid Electric Vehicle(HEV. Modelling methods such as physics-based Resistive Companion Form technique and Bond Graph method are presented with powertrain component and system modelling examples. The modelling and simulation capability of existing tools such as ADvanced VehIcle SimulatOR (ADVISOR is demonstrated through application examples. Since power electronics is indispensable in hybrid vehicles, the issue of numerical oscillations in dynamic simulations involving power electronics is briefly addressed.

  10. Effects of binders on the performance of electric double-layer capacitors of carbon nanotube electrodes

    Institute of Scientific and Technical Information of China (English)

    LI Chensha; WANG Dazhi; ZHANG Baoyou; WANG Xiaofeng; CAO Maosheng; LIANG Ji

    2005-01-01

    Polarizable electrodes of electric double layer capacitor (EDLCs) were made from carhon nanotubes. Effects of different binders, which are phenolic resin (PF) and polytetrafluoroethylene (PTFE), on the properties of polarizable electrodes are studied. Results indicate that the microstructure, pore size distribution and specific capacitance of the electrodes with PTFE binder are superior to those electrodes with PF binder after carbonization. The suitable binder (PTFE) for carbon nanotubes electrodes is proposed.

  11. Measurement and Evaluation of Heating Performance of Heat Pump Systems Using Wasted Heat from Electric Devices for an Electric Bus

    Directory of Open Access Journals (Sweden)

    Moo-Yeon Lee

    2012-03-01

    Full Text Available The objective of this study is to investigate heating performance characteristics of a coolant source heat pump using the wasted heat from electric devices for an electric bus. The heat pump, using R-134a, is designed for heating a passengers’ compartment by using discharged energy from the coolant of electric devices, such as motors and inverters of the electric bus. The heating performance of the heat pump was tested by varying the operating parameters, such as outdoor temperature and volume flow rate of the coolant water of the electrical devices. Heating capacity, compressor work, and heating COP were measured; their behaviors with regard to the parameters were observed. Experimental results showed that heating COP increased with decrease of outdoor temperature, from 20.0 °C to 0 °C, and it observed to be 3.0 in the case of 0 °C outdoor temperature. The observed characteristics of the heating COP suggest that the heat pump is applicable as the cabin heater of an electric vehicle, which is limited by short driving range.

  12. Sectoral Innovation Performance in the Electrical and Optical Equipment Sector

    NARCIS (Netherlands)

    Broek, T. van den; Giessen, A.M. van der

    2010-01-01

    The Electrical and Optical equipment sector is a high-tech manufacturing sector. It is one of the most innovative sectors in Europe with investments and advances in fundamental research, applied R&D and innovation in the actual use of equipment. This sector is also one of the most global sectors

  13. Electric-field enhanced performance in catalysis and solid-state devices involving gases

    Science.gov (United States)

    Blackburn, Bryan M.; Wachsman, Eric D.; Van Assche, IV, Frederick Martin

    2015-05-19

    Electrode configurations for electric-field enhanced performance in catalysis and solid-state devices involving gases are provided. According to an embodiment, electric-field electrodes can be incorporated in devices such as gas sensors and fuel cells to shape an electric field provided with respect to sensing electrodes for the gas sensors and surfaces of the fuel cells. The shaped electric fields can alter surface dynamics, system thermodynamics, reaction kinetics, and adsorption/desorption processes. In one embodiment, ring-shaped electric-field electrodes can be provided around sensing electrodes of a planar gas sensor.

  14. Multiwalled carbon nanotube/polydimethylsiloxane composite films as high performance flexible electric heating elements

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Jing; Jeong, Young Gyu, E-mail: ygjeong@cnu.ac.kr [Department of Advanced Organic Materials and Textile System Engineering, Chungnam National University, Daejeon 305-764 (Korea, Republic of)

    2014-08-04

    High performance elastomeric electric heating elements were prepared by incorporating various contents of pristine multiwalled carbon nanotube (MWCNT) in polydimethylsiloxane (PDMS) matrix by using an efficient solution-casting and curing technique. The pristine MWCNTs were identified to be uniformly dispersed in the PDMS matrix and the electrical percolation of MWCNTs was evaluated to be at ∼0.27 wt. %, where the electrical resistivity of the MWCNT/PDMS composite films dropped remarkably. Accordingly, the composite films with higher MWCNT contents above 0.3 wt. % exhibit excellent electric heating performance in terms of temperature response rapidity and electric energy efficiency at constant applied voltages. In addition, the composite films, which were thermally stable up to 250 °C, showed excellent heating-cooling cyclic performance, which was associated with operational stability in actual electric heating applications.

  15. Evaluation of High-Performance Space Nuclear Electric Generators for Electric Propulsion Application

    Science.gov (United States)

    Woodcock, Gordon; Kross, Dennis A. (Technical Monitor)

    2002-01-01

    Electric propulsion applications are enhanced by high power-to-mass ratios for their electric power sources. At multi-megawatt levels, we can expect thrust production systems to be less than 5 kg/kWe. Application of nuclear electric propulsion to human Mars missions becomes an attractive alternative to nuclear thermal propulsion if the propulsion system is less than about 10 kg/kWe. Recent references have projected megawatt-plus nuclear electric sources at specific mass values from less than 1 kg/kWe to about 5 kg/kWe. Various assumptions are made regarding power generation cycle (turbogenerator; MHD (magnetohydrodynamics)) and reactor heat source design. The present paper compares heat source and power generation options on the basis of a parametric model that emphasizes heat transfer design and realizable hardware concept. Pressure drop (important!) is included in the power cycle analysis, and MHD and turbogenerator cycles are compared. Results indicate that power source specific mass less than 5 kg/kWe is attainable, even if peak temperatures achievable are limited to 1500 K. Projections of specific mass less than 1 kg/kWe are unrealistic, even at the highest peak temperatures considered.

  16. The superior cycling performance of the hydrothermal synthesized carbon-coated ZnO as anode material for zinc-nickel secondary cells

    Science.gov (United States)

    Feng, Zhaobin; Yang, Zhanhong; Huang, Jianhang; Xie, Xiaoe; Zhang, Zheng

    2015-02-01

    Carbon-coated ZnO is synthesized by the hydrothermal method. The X-ray diffraction (XRD), scanning electron microscope (SEM), high resolution transmission electron microscopy (HRTEM) and energy dispersive X-ray analysis (EDX) tests indicate that carbon is uniformly coated on the surface of the ZnO particle. And the crystal form of ZnO isn't changed. The effects of carbon layer on the electrochemical performances of ZnO have also been investigated by the charge/discharge cycling test, cyclic voltammetry (CV), Tafel polarization curves and electrochemical impedance spectroscope (EIS) tests. The CV curves at different scan rates exhibit that carbon-coated ZnO has the superior reversibility at high scan rate. The charge/discharge cycling tests under different charge/discharge rates show, even if at high-rate, the cycling performance and specific discharge capacity of carbon-coated ZnO are also superior to that of bare ZnO. The Tafel polarization curves and electrochemical impedance spectroscope (EIS) verify that the carbon layer can improve the anti-corrosion and charge-transfer performances of ZnO. The different rate experiments indicate that, compared with the increase of the conductivity, the effect of carbon layer on improving the anti-corrosion performance of ZnO plays a more dominating role in improving the electrochemical performances of ZnO at low charge/discharge rate.

  17. Performance Analysis of Induction Motor of Electric Vehicle Using Vector control

    Institute of Scientific and Technical Information of China (English)

    Liu ping

    2012-01-01

    According to the principle of Vector controlused in an asyn- chronous motor,a simulation model of the asynchronous motor in elec-tric vehicle and Vectorcontrolsystem was established with Matlab/Simu-link software. Simulation analysis of the asynchronous motor driving an electric vehicle was performedunder the classic mode of EV , and the simulation results show the modeland control scheme has better stable and dynamic performance,whichcanbe a good candidate for electric ve- hicle propulsion system

  18. Speed and Vibration Performance as well as Obstacle Avoidance Performance of Electric Wheel Chair Controlled by Human Eyes Only

    Directory of Open Access Journals (Sweden)

    Kohei Arai

    2014-01-01

    Full Text Available Speed and vibration performance as well as obstacle avoidance performance of the previously proposed Electric Wheel Chair: EWC controlled by human eyes only is conducted. Experimental results show acceptable performances of speed vibration performance as well as obstacle avoidance performance for disabled persons. More importantly, disabled persons are satisfied with the proposed EWC because it works by their eyes only. Without hands and finger, they can control EWC freely.

  19. A Green Synthesis of Nanosheet-Constructed Pd Particles in an Ionic Liquid and Their Superior Electrocatalytic Performance.

    Science.gov (United States)

    Zhang, Baohua; Xue, Yiguo; Xue, Zhimin; Li, Zhonghao; Hao, Jingcheng

    2015-12-21

    The ionic liquid 1-ethyl-3-methylimidazolium acetate ([EMIM]Ac) is investigated as a solvent for the synthesis of Pd particles. Interestingly, nanosheet-constructed Pd particles could be successfully synthesized in [EMIM]Ac without any additional reducing agent and template under ionothermal conditions. [EMIM]Ac itself works as the solvent, the reducing agent, and the template for the formation of these interesting Pd particles, making this method complementary to the well-known ionic-liquid-precursor approach. Furthermore, [EMIM]Ac can be recycled with no loss of activity for the formation of nanosheet-constructed Pd particles within our studied cycles. Specifically, the nanosheet-constructed Pd particles exhibit superior electrocatalytic activity and stability towards ethanol oxidation and formic acid oxidation compared with commercially available Pd black catalyst, thus demonstrating their promising applications in fuel-cell area. The current approach, thus, presents a green approach towards the synthesis of Pd particles, using only a simple palladium salt and an ionic liquid. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Predictive Model of Graphene Based Polymer Nanocomposites: Electrical Performance

    Science.gov (United States)

    Manta, Asimina; Gresil, Matthieu; Soutis, Constantinos

    2017-04-01

    In this computational work, a new simulation tool on the graphene/polymer nanocomposites electrical response is developed based on the finite element method (FEM). This approach is built on the multi-scale multi-physics format, consisting of a unit cell and a representative volume element (RVE). The FE methodology is proven to be a reliable and flexible tool on the simulation of the electrical response without inducing the complexity of raw programming codes, while it is able to model any geometry, thus the response of any component. This characteristic is supported by its ability in preliminary stage to predict accurately the percolation threshold of experimental material structures and its sensitivity on the effect of different manufacturing methodologies. Especially, the percolation threshold of two material structures of the same constituents (PVDF/Graphene) prepared with different methods was predicted highlighting the effect of the material preparation on the filler distribution, percolation probability and percolation threshold. The assumption of the random filler distribution was proven to be efficient on modelling material structures obtained by solution methods, while the through-the -thickness normal particle distribution was more appropriate for nanocomposites constructed by film hot-pressing. Moreover, the parametrical analysis examine the effect of each parameter on the variables of the percolation law. These graphs could be used as a preliminary design tool for more effective material system manufacturing.

  1. Electrical equipment performance under severe accident conditions (BWR/Mark 1 plant analysis): Summary report

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, P.R.; Kolaczkowski, A.M.; Medford, G.T.

    1986-09-01

    The purpose of the Performance Evaluation of Electrical Equipment during Severe Accident States Program is to determine the performance of electrical equipment, important to safety, under severe accident conditions. In FY85, a method was devised to identify important electrical equipment and the severe accident environments in which the equipment was likely to fail. This method was used to evaluate the equipment and severe accident environments for Browns Ferry Unit 1, a BWR/Mark I. Following this work, a test plan was written in FY86 to experimentally determine the performance of one selected component to two severe accident environments.

  2. Performance results of a solar greenhouse combining electrical and thermal energy production

    NARCIS (Netherlands)

    Sonneveld, P.J.; Swinkels, G.L.A.M.; Campen, J.B.; Tuijl, van B.A.J.; Janssen, H.J.J.; Bot, G.P.A.

    2010-01-01

    Performance results are given of a new type of greenhouse, which combines reflection of near infrared radiation (NIR) with electrical power generation using hybrid photovoltaic cell/thermal collector modules. Besides the generation of electrical and thermal energy, the reflection of the NIR will res

  3. Performance results of a solar greenhouse combining electrical and thermal energy production

    NARCIS (Netherlands)

    Sonneveld, P.J.; Swinkels, G.L.A.M.; Campen, J.B.; Tuijl, van B.A.J.; Janssen, H.J.J.; Bot, G.P.A.

    2010-01-01

    Performance results are given of a new type of greenhouse, which combines reflection of near infrared radiation (NIR) with electrical power generation using hybrid photovoltaic cell/thermal collector modules. Besides the generation of electrical and thermal energy, the reflection of the NIR will

  4. Evaluation of SF6-alternative gas C5-PFK based on arc extinguishing performance and electric strength

    Science.gov (United States)

    Wu, Yi; Wang, Chunlin; Sun, Hao; Rong, Mingzhe; Murphy, Anthony Bruce; Li, Tianwei; Zhong, Jianying; Chen, Zhexin; Yang, Fei; Niu, Chunpin

    2017-09-01

    C5-PFK (C5-perfluoroketone, C5F10O) is under wide consideration as an environmentally-friendly alternative gas to SF6 in high-voltage applications, because of its superior insulation performance. The aim of this work is to study theoretically the arc extinguishing performance and electric strength of C5-PFK. The arc extinguishing performance of C5-PFK was evaluated by analyzing and comparing the thermophysical properties of C5-PFK, SF6, CF4, CO2 and N2 plasmas. It was difficult to obtain the species formed in C5-PFK plasmas because of the complex C5-PFK molecular decomposition process. In this work, the decomposition process of C5-PFK and the related species were analyzed by the bond energy analysis method. For the species for which parameters such as the partition function and the enthalpy of formation were not available, computational chemistry methods were used to obtain the required data. The collision integrals were calculated using the phenomenological potential model. Using these results, the local thermodynamic equilibrium composition at temperatures from 300 to 30 000 K at 1-10 atm of pure C5-PFK was calculated by the method of minimization of the Gibbs free energy, and the corresponding transport coefficients were calculated by Chapman-Enskog method. Through the comparison of the thermophysical properties, it was found that C5-PFK had similar characteristics to SF6, with large peaks in specific heat below 4500 K, indicating potentially good thermal interruption capability. However, the specific heat peak at 7000 K corresponding to CO decomposition may detract from the thermal interruption capability. Specific heat peaks at higher temperatures are associated with the breaking of double or triple bonds, and should be avoided if possible in the new alternative gases. The electric strength of C5-PFK was assessed using the molecular electrostatic potential, which can be accurately calculated or measured, and gives strong insights into important

  5. A novel graphene nanoribbon FET with an extra peak electric field (EFP-GNRFET) for enhancing the electrical performances

    Energy Technology Data Exchange (ETDEWEB)

    Akbari Eshkalak, Maedeh [Young Researchers and Elite Club, Lahijan Branch, Islamic Azad University, Lahijan (Iran, Islamic Republic of); Anvarifard, Mohammad K., E-mail: m.anvarifard@guilan.ac.ir [Department of Engineering Sciences, Faculty of Technology and Engineering, East of Guilan, University of Guilan, Rudsar-Vajargah (Iran, Islamic Republic of)

    2017-04-25

    This work has provided an efficient technique to improve the electrical performance for the Graphene Nanoribbon Field Effect Transistors (GNRFETs) successfully. The physical gate length is divided into two gates named as the original gate and the other one as the virtual gate. We have applied a voltage source between these gates to control the channel of the GNRFETs. This technique has created an extra peak electric field in the middle of the channel resulting in the redistribution of surface potential profile. The proposed structure named as EFP-GNRFET has been compared with a simple GNRFET and has shown many improvements in terms of the critical parameters such as short channel effects, leakage current, subthreshold swing, ON-state to OFF-state current ratio, transconductance, output conductance and voltage gain. The structures under the study in this paper benefits from the Non-Equilibrium Green Function (NEGF) approach for solving Schrödinger equation coupled with the two-dimensional (2D) Poisson equation in a self-consistent manner. - Highlights: • Proposal of a novel graphene nanoribbon FET. • Creation of an extra peak in electric field. • Modification of the channel potential with the help of virtual gate. • Considerable improvement on electrical performances.

  6. The performance of residential micro-cogeneration coupled with thermal and electrical storage

    Science.gov (United States)

    Kopf, John

    Over 80% of residential secondary energy consumption in Canada and Ontario is used for space and water heating. The peak electricity demands resulting from residential energy consumption increase the reliance on fossil-fuel generation stations. Distributed energy resources can help to decrease the reliance on central generation stations. Presently, distributed energy resources such as solar photovoltaic, wind and bio-mass generation are subsidized in Ontario. Micro-cogeneration is an emerging technology that can be implemented as a distributed energy resource within residential or commercial buildings. Micro-cogeneration has the potential to reduce a building's energy consumption by simultaneously generating thermal and electrical power on-site. The coupling of a micro-cogeneration device with electrical storage can improve the system's ability to reduce peak electricity demands. The performance potential of micro-cogeneration devices has yet to be fully realized. This research addresses the performance of a residential micro-cogeneration device and it's ability to meet peak occupant electrical loads when coupled with electrical storage. An integrated building energy model was developed of a residential micro-cogeneration system: the house, the micro-cogeneration device, all balance of plant and space heating components, a thermal storage device, an electrical storage device, as well as the occupant electrical and hot water demands. This model simulated the performance of a micro-cogeneration device coupled to an electrical storage system within a Canadian household. A customized controller was created in ESP-r to examine the impact of various system control strategies. The economic performance of the system was assessed from the perspective of a local energy distribution company and an end-user under hypothetical electricity export purchase price scenarios. It was found that with certain control strategies the micro-cogeneration system was able to improve the

  7. Improving the performance of a hybrid electric vehicle by utilization regenerative braking energy of vehicle

    Directory of Open Access Journals (Sweden)

    Mohamed Mourad

    2011-01-01

    Full Text Available Environmentally friendly vehicles with range and performance capabilities surpassing those of conventional ones require a careful balance among competing goals for fuel efficiency, performance and emissions. It can be recuperated the energy of deceleration case of the vehicle to reuse it to recharge the storage energy of hybrid electric vehicle and increase the state of charge of batteries under the new conditions of vehicle operating in braking phase. Hybrid electric vehicle has energy storage which allows decreasing required peak value of power from prime mover, which is the internal combustion engine. The paper investigates the relationships between the driving cycle phases and the recuperation energy to the batteries system of hybrid electric vehicle. This work describes also a methodology for integrating this type of hybrid electric vehicle in a simulation program. A design optimization framework is then used to find the best position that we can utilize the recuperation energy to recharge the storage batteries of hybrid electric vehicle.

  8. Cooling Performance Characteristics on Mobile Air-Conditioning System for Hybrid Electric Vehicles

    OpenAIRE

    Ho-Seong Lee; Moo-Yeon Lee

    2013-01-01

    This study investigates the cooling performance characteristics of the mobile air-conditioning system using R744 (CO2) for the hybrid electric vehicle as an alternative to both the R-134a and the conventional air-conditioning system. The developed air-conditioning system is operated with an electric driven compressor in the battery driving mode and a belt driven compressor in the engine driving mode. The cooling performance characteristics of the developed system have been analyzed by experim...

  9. Expanded graphite embedded with aluminum nanoparticles as superior thermal conductivity anodes for high-performance lithium-ion batteries.

    Science.gov (United States)

    Zhao, Tingkai; She, Shengfei; Ji, Xianglin; Guo, Xinai; Jin, Wenbo; Zhu, Ruoxing; Dang, Alei; Li, Hao; Li, Tiehu; Wei, Bingqing

    2016-09-27

    The development of high capacity and long-life lithium-ion batteries is a long-term pursuing and under a close scrutiny. Most of the researches have been focused on exploring electrode materials and structures with high store capability of lithium ions and at the same time with a good electrical conductivity. Thermal conductivity of an electrode material will also have significant impacts on boosting battery capacity and prolonging battery lifetime, which is, however, underestimated. Here, we present the development of an expanded graphite embedded with Al metal nanoparticles (EG-MNPs-Al) synthesized by an oxidation-expansion process. The synthesized EG-MNPs-Al material exhibited a typical hierarchical structure with embedded Al metal nanoparticles into the interspaces of expanded graphite. The parallel thermal conductivity was up to 11.6 W·m(-1)·K(-1) with a bulk density of 453 kg·m(-3) at room temperature, a 150% improvement compared to expanded graphite (4.6 W·m(-1)·K(-1)) owing to the existence of Al metal nanoparticles. The first reversible capacity of EG-MNPs-Al as anode material for lithium ion battery was 480 mAh·g(-1) at a current density of 100 mA·g(-1), and retained 84% capacity after 300 cycles. The improved cycling stability and system security of lithium ion batteries is attributed to the excellent thermal conductivity of the EG-MNPs-Al anodes.

  10. Expanded graphite embedded with aluminum nanoparticles as superior thermal conductivity anodes for high-performance lithium-ion batteries

    Science.gov (United States)

    Zhao, Tingkai; She, Shengfei; Ji, Xianglin; Guo, Xinai; Jin, Wenbo; Zhu, Ruoxing; Dang, Alei; Li, Hao; Li, Tiehu; Wei, Bingqing

    2016-09-01

    The development of high capacity and long-life lithium-ion batteries is a long-term pursuing and under a close scrutiny. Most of the researches have been focused on exploring electrode materials and structures with high store capability of lithium ions and at the same time with a good electrical conductivity. Thermal conductivity of an electrode material will also have significant impacts on boosting battery capacity and prolonging battery lifetime, which is, however, underestimated. Here, we present the development of an expanded graphite embedded with Al metal nanoparticles (EG-MNPs-Al) synthesized by an oxidation-expansion process. The synthesized EG-MNPs-Al material exhibited a typical hierarchical structure with embedded Al metal nanoparticles into the interspaces of expanded graphite. The parallel thermal conductivity was up to 11.6 W·m-1·K-1 with a bulk density of 453 kg·m-3 at room temperature, a 150% improvement compared to expanded graphite (4.6 W·m-1·K-1) owing to the existence of Al metal nanoparticles. The first reversible capacity of EG-MNPs-Al as anode material for lithium ion battery was 480 mAh·g-1 at a current density of 100 mA·g-1, and retained 84% capacity after 300 cycles. The improved cycling stability and system security of lithium ion batteries is attributed to the excellent thermal conductivity of the EG-MNPs-Al anodes.

  11. Design Elements and Electrical Performance of a Bifacial BIPV Module

    Directory of Open Access Journals (Sweden)

    Jun-Gu Kang

    2016-01-01

    Full Text Available Bifacial BIPV systems have great potential when applied to buildings given their use of a glass-to-glass structure. However, the performance of bifacial solar cells depends on a variety of design factors. Therefore, in order to apply bifacial solar cells to buildings, a bifacial PV module performance analysis should be carried out, including consideration of the various design elements and reflecting a wide range of installation conditions. This study focuses on the performance of a bifacial BIPV module applied to a building envelope. The results here show that the design elements of reflectivity and the transparent space ratio have the greatest impact on performance levels. The distance between the module and the wall had less of an impact on performance. The bifacial BIPV module produced output up to 30% greater than the output of monofacial PV modules, depending on the design elements. Bifacial BIPV modules themselves should have transparent space ratios of at least 30%. When a dark color is used on the external wall with reflectivity of 50% or less, bifacial BIPV modules with transparent space ratios of 40% and above should be used. In order to achieve higher performance through the installation of bifacial BIPV modules, design conditions which facilitate reflectivity exceeding 50% and a transparent space ratio which exceeds 30% must be met.

  12. A Study on Electrical Performances and Lifetime of a Flexible Electrochromic Textile Device

    Directory of Open Access Journals (Sweden)

    Moretti Constance

    2014-06-01

    Full Text Available Using their ability to change their color according to an external stimulation, chromic materials can be used to form a color-changing textile. Electrochromism, more particularly, is a colour change phenomenon caused by the application of an electrical potential. A flexible textile electrochromic device composed of four layers is presented. In order to improve the lifetime of this structure, the electrical performances of the electrolyte layer are studied. A method to measure and calculate the resistance variations of the electrolyte applied on a textile cotton substrate is given. Relations between the electrical performances of the electrolyte and the electrochromic effect of the device are also highlighted.

  13. Expanded graphite embedded with aluminum nanoparticles as superior thermal conductivity anodes for high-performance lithium-ion batteries

    Science.gov (United States)

    Zhao, Tingkai; She, Shengfei; Ji, Xianglin; Guo, Xinai; Jin, Wenbo; Zhu, Ruoxing; Dang, Alei; Li, Hao; Li, Tiehu; Wei, Bingqing

    2016-01-01

    The development of high capacity and long-life lithium-ion batteries is a long-term pursuing and under a close scrutiny. Most of the researches have been focused on exploring electrode materials and structures with high store capability of lithium ions and at the same time with a good electrical conductivity. Thermal conductivity of an electrode material will also have significant impacts on boosting battery capacity and prolonging battery lifetime, which is, however, underestimated. Here, we present the development of an expanded graphite embedded with Al metal nanoparticles (EG-MNPs-Al) synthesized by an oxidation-expansion process. The synthesized EG-MNPs-Al material exhibited a typical hierarchical structure with embedded Al metal nanoparticles into the interspaces of expanded graphite. The parallel thermal conductivity was up to 11.6 W·m−1·K−1 with a bulk density of 453 kg·m−3 at room temperature, a 150% improvement compared to expanded graphite (4.6 W·m−1·K−1) owing to the existence of Al metal nanoparticles. The first reversible capacity of EG-MNPs-Al as anode material for lithium ion battery was 480 mAh·g−1 at a current density of 100 mA·g−1, and retained 84% capacity after 300 cycles. The improved cycling stability and system security of lithium ion batteries is attributed to the excellent thermal conductivity of the EG-MNPs-Al anodes. PMID:27671848

  14. What doesn't kill me…: Adversity-related experiences are vital in the development of superior Olympic performance.

    Science.gov (United States)

    Sarkar, Mustafa; Fletcher, David; Brown, Daniel J

    2015-07-01

    Recent research suggests that experiencing some adversity can have beneficial outcomes for human growth and development. The purpose of this paper was to explore the adversities that the world's best athletes encounter and the perceived role that these experiences play in their psychological and performance development. A qualitative design was employed because detailed information of rich quality was required to better understand adversity-related experiences in the world's best athletes. Semi-structured interviews were conducted with 10 Olympic gold medalists from a variety of sports. Inductive thematic analysis was used to analyze the data. The findings indicate that the participants encountered a range of sport- and non-sport adversities that they considered were essential for winning their gold medals, including repeated non-selection, significant sporting failure, serious injury, political unrest, and the death of a family member. The participants described the role that these experiences played in their psychological and performance development, specifically focusing on their resultant trauma, motivation, and learning. Adversity-related experiences were deemed to be vital in the psychological and performance development of Olympic champions. In the future, researchers should conduct more in-depth comparative studies of Olympic athletes' adversity- and growth-related experiences, and draw on existing and alternative theoretical explanations of the growth-performance relationship. For professional practitioners, adversity-related experiences offer potential developmental opportunities if they are carefully and purposely harnessed. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  15. Co-based ternary nanocomposites: synthesis and their superior performances for hydrogenation of p-nitrophenol and adsorption for methyl blue

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Fang-Yuan; Fan, Yan-Ling; Ni, Jing-Jing; Xu, Ting-Ting; Song, Ji-Ming, E-mail: songjm@ahu.edu.cn, E-mail: jiming@ahu.edu.cn [Anhui University, The Key Laboratory of Environment Friendly Polymer Materials of Anhui Province, School of Chemistry & Chemical Engineering (China)

    2016-01-15

    A new kind of Co-based ternary nanocomposites has been obtained via one step without any additional surfactant at zero centigrade degree. Some experimental parameters play crucial roles in determining the morphologies and homogeneity of the final products, such as reaction temperature and the introduction of Na{sub 2}S{sub 2}O{sub 3}·5H{sub 2}O. The samples were characterized by XRD, SEM, TEM, UV–Vis, XPS, and BET. The result reveals that the as-prepared samples are Co{sub 1.29}Ni{sub 1.71}O{sub 4}–Co{sub 3}S{sub 4}–Co{sub 3}O{sub 4} Co-based ternary nanocomposites with an elliptic morphology composed of numerous fold-shaped superthin films (average thickness of ca. 2 nm). Interestingly, the obtained nanocomposites display superior performance for the hydrogenation of p-nitrophenol at room temperature in the presence of NaBH{sub 4}. More importantly, the as-prepared nanocomposites show the huge adsorption capacity for methyl blue at room temperature, reaches 1100 mg g{sup −1}. Graphical Abstract: A kind of new-type Co-based ternary nanocomposites has been obtained via one step without surfactants at zero centigrade degree. The as-prepared nanocomposites display superior performance for the hydrogenation of p-nitrophenol in the presence of NaBH{sub 4} at room temperature.

  16. High Pseudocapacitance in FeOOH/rGO Composites with Superior Performance for High Rate Anode in Li-Ion Battery.

    Science.gov (United States)

    Qi, Hui; Cao, Liyun; Li, Jiayin; Huang, Jianfeng; Xu, Zhanwei; Cheng, Yayi; Kong, Xingang; Yanagisawa, Kazumichi

    2016-12-28

    Capacitive storage has been considered as one type of Li-ion storage with fast faradaic surface redox reactions to offer high power density for electrochemical applications. However, it is often limited by low extent of energy contribution during the charge/discharge process, providing insufficient influences to total capacity of Li-ion storage in electrodes. In this work, we demonstrate a pseudocapacitance predominated storage (contributes 82% of the total capacity) from an in-situ pulverization process of FeOOH rods on rGO (reduced graphene oxide) sheets for the first time. Such high extent of pseudocapacitive storage in the FeOOH/rGO electrode achieves high energy density with superior cycling performance over 200 cycles at different current densities (1135 mAh/g at 1 A/g and 783 mAh/g at 5 A/g). It is further revealed that the in-situ pulverization process is essential for the high pseudocapacitance in this electrode, because it not only produces a porous structure for high exposure of tiny FeOOH crystallites to electrolyte but also maintains stable electrochemical contact during ultrahigh rate charge transfer with high energy density in the battery. The utilization of in-situ pulverization in an Fe-based anode to realize high surface pseudocapacitance with superior performance may inspire future design of electrode structures in Li-ion batteries.

  17. Superior electrochemical performance of sulfur/graphene nanocomposite material for high-capacity lithium-sulfur batteries.

    Science.gov (United States)

    Wang, Bei; Li, Kefei; Su, Dawei; Ahn, Hyojun; Wang, Guoxiu

    2012-06-01

    Sulfur/graphene nanocomposite material has been prepared by incorporating sulfur into the graphene frameworks through a melting process. Field-emission scanning electron microscope analysis shows a homogeneous distribution of sulfur in the graphene nanosheet matrix. The sulfur/graphene nanocomposite exhibits a super-high lithium-storage capacity of 1580 mA h g(-1) and a satisfactory cycling performance in lithium-sulfur cells. The enhancement of the reversible capacity and cycle life could be attributed to the flexible graphene nanosheet matrix, which acts as a conducting medium and a physical buffer to cushion the volume change of sulfur during the lithiation and delithiation process. Graphene-based nanocomposites can significantly improve the electrochemical performance of lithium-sulfur batteries.

  18. Enhancing Electrode Performance by Exsolved Nanoparticles: A Superior Cobalt-Free Perovskite Electrocatalyst for Solid Oxide Fuel Cells.

    Science.gov (United States)

    Yang, Guangming; Zhou, Wei; Liu, Meilin; Shao, Zongping

    2016-12-28

    The successful development of low-cost, durable electrocatalysts for oxygen reduction reaction (ORR) at intermediate temperatures is critical for broad commercialization of solid oxide fuel cells. Here, we report our findings in design, fabrication, and characterization of a cobalt-free SrFe0.85Ti0.1Ni0.05O3-δ cathode decorated with NiO nanoparticles. Exsolved from and well bonded to the parent electrode under well-controlled conditions, the NiO nanoparticles uniformly distributed on the surface of the parent electrode greatly enhance cathode performance, demonstrating ORR activity better than that of the benchmark cobalt-based Ba0.5Sr0.5Co0.8Fe0.2O3-δ. Further, a process for regeneration of the NiO nanoparticles was also developed to mitigate potential performance degradation due to coarsening of NiO particles under practical operating conditions. As a general approach, this exsolution-dissolution of electrocatalytically active nanoparticles on an electrode surface may be applicable to the development of other high-performance cobalt-free cathodes for fuel cells and other electrochemical systems.

  19. Evaluation of the Demand Response Performance of Electric Water Heaters

    Energy Technology Data Exchange (ETDEWEB)

    Mayhorn, Ebony T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Widder, Sarah H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Parker, Steven A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pratt, Richard M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Chassin, Forrest S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-03-17

    The purpose of this project is to verify or refute many of the concerns raised by utilities regarding the ability of large tank HPWHs to perform DR by measuring the performance of HPWHs compared to ERWHs in providing DR services. perform DR by measuring the performance of HPWHs compared to ERWHs in providing DR services. This project was divided into three phases. Phase 1 consisted of week-long laboratory experiments designed to demonstrate technical feasibility of individual large-tank HPWHs in providing DR services compared to large-tank ERWHs. In Phase 2, the individual behaviors of the water heaters were then extrapolated to a population by first calibrating readily available water heater models developed in GridLAB-D simulation software to experimental results obtained in Phase 1. These models were used to simulate a population of water heaters and generate annual load profiles to assess the impacts on system-level power and residential load curves. Such population modeling allows for the inherent and permanent load reduction accomplished by the more efficient HPWHs to be considered, in addition to the temporal DR services the water heater can provide by switching ON or OFF as needed by utilities. The economic and emissions impacts of using large-tank water heaters in DR programs are then analyzed from the utility and consumer perspective, based on National Impacts Analysis in Phase 3. Phase 1 is discussed in this report. Details on Phases 2 and 3 can be found in the companion report (Cooke et al. 2014).

  20. High-Quality Fe-doped TiO2 films with Superior Visible-Light Performance

    DEFF Research Database (Denmark)

    Su, Ren; Bechstein, Ralf; Kibsgaard, Jakob

    2012-01-01

    We report on high-quality polycrystalline Fe-doped TiO2 (Fe–TiO2) porous films synthesized via one-step electrochemical oxidation. We demonstrate that delicate properties such as the impurity concentration and the microstructure that strongly influence the performance of the material...... for photovoltaic and photocatalysis applications can be controlled by adjusting the electrolyte composition. Compared to Fe-doped TiO2 films prepared with traditional phosphate- or silicate-based electrolytes, our newly synthesised Fe–TiO2 films contain solely Fe dopants, which results in excellent photocatalytic...

  1. Modelo de avaliação de desempenho global para instituição de ensino superior Evaluation Model of Global Performance for Higher Education Institutions

    Directory of Open Access Journals (Sweden)

    Henrique Martins Galvão

    2011-12-01

    Full Text Available This study proposes a model to evaluate overall performance for Higher Education Institutions. It is unquestionable the importance of organizations from the education sector for knowledge development and dissemination of information, necessary for the progress of a city, region or country. However, it is necessary to develop tools for planning and management control to monitor organizational performance. In this case, one of the most important tasks is related to the types of information that managers need to monitor and tune the performance of the organization. The proposed evaluation model helps to improve the organizational performance of education institutions, creating higher value in the services offered.Este estudo propõe um modelo de avaliação de desempenho global para instituições de ensino superior. É indiscutível a importância das organizações do setor da educação, decisivas para o progresso de uma cidade, região ou país, por serem indutoras do desenvolvimento do conhecimento e da disseminação da informação. Por isso, torna-se necessário desenvolver, para essas instituições educacionais, instrumentos gerenciais de planejamento e de controle que monitorem o desempenho organizacional. Neste caso, uma das tarefas mais relevantes relaciona-se aos tipos de informações que os gerentes necessitam para monitorar e ajustar o desempenho da organização. O modelo de avaliação proposto contribui para melhorar o desempenho organizacional das instituições de ensino, criando valor superior nos serviços oferecidos.

  2. Comparison of Electrical and Thermal Performances of Glazed and Unglazed PVT Collectors

    Directory of Open Access Journals (Sweden)

    Jin-Hee Kim

    2012-01-01

    Full Text Available Photovoltaic-thermal (PVT collectors combine photovoltaic modules and solar thermal collectors, forming a single device that receives solar radiation and produces electricity and heat simultaneously. PVT collectors can produce more energy per unit surface area than side-by-side PV modules and solar thermal collectors. There are two types of liquid-type flat-plate PVT collectors, depending on the existence of glass cover over PV module: glass-covered (glazed PVT collectors, which produce relatively more thermal energy but have lower electrical yield, and uncovered (unglazed PVT collectors, which have relatively lower thermal energy with somewhat higher electrical performance. In this paper, the experimental performance of two types of liquid-type PVT collectors, glazed and unglazed, was analyzed. The electrical and thermal performances of the PVT collectors were measured in outdoor conditions, and the results were compared. The results show that the thermal efficiency of the glazed PVT collector is higher than that of the unglazed PVT collector, but the unglazed collector had higher electrical efficiency than the glazed collector. The overall energy performance of the collectors was compared by combining the values of the average thermal and electrical efficiency.

  3. Are performance-based functional assessments superior to semistructured interviews for enhancing return-to-work outcomes?

    Science.gov (United States)

    Gross, Douglas P; Asante, Alexander K; Miciak, Maxi; Battié, Michele C; Carroll, Linda J; Sun, Ambrose; Mikalsky, Marti; Huellstrung, Rene; Niemeläinen, Riikka

    2014-05-01

    To examine whether use of functional capacity evaluation (FCE) leads to better outcomes for injured workers. Cluster randomized controlled trial conducted with analysis at level of claimant. Rehabilitation facility. Participants included claimants (N=203); of these, 103 were tested with FCE. Data were collected on all claimants undergoing RTW assessment at the facility for musculoskeletal conditions. Participants were predominantly employed (59%) men (73%) with chronic musculoskeletal conditions (median duration, 496d). FCEs are commonly used to identify work abilities and inform return-to-work (RTW) decisions. Therefore, FCE results have important consequences. Clinicians who were trained and experienced in performing FCEs were randomized into 2 groups. One group included 14 clinicians who were trained to conduct a semistructured functional interview; the other group (control group) continued to use standard FCE procedures. Outcomes included RTW recommendations after assessment, functional work level at time of assessment and 1, 3, and 6 months after assessment, and compensation outcomes. Analysis included Mann-Whitney U, chi-square, and t tests. All outcomes were similar between groups, and no statistically or clinically significant differences were observed. Mean differences between groups on functional work levels at assessment and follow-up ranged from 0.1 to 0.3 out of 4 (3%-8% difference, P>.05). Performance-based FCEs did not appear to enhance RTW outcomes beyond information gained from semistructured functional interviewing. Use of functional interviewing has the potential to improve efficiency of RTW assessment without compromising clinical, RTW, or compensation outcomes. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  4. Superior performance of highly flexible solid-state supercapacitor based on the ternary composites of graphene oxide supported poly(3,4-ethylenedioxythiophene)-carbon nanotubes

    Science.gov (United States)

    Zhou, Haihan; Zhai, Hua-Jin; Han, Gaoyi

    2016-08-01

    Ternary composite electrodes based on carbon nanotubes thin films (CNFs)-loaded graphene oxide (GO) supported poly(3,4-ethylenedioxythiophene)- carbon nanotubes (GO/PEDOT-CNTs) have been prepared via a facile one-step electrochemical codeposition method. The effect of long and short CNTs-incorporated composites (GO/PEDOT-lCNTs and GO/PEDOT-sCNTs) on the electrochemical behaviors of the electrodes is investigated and compared. Electrochemical measurements indicate that the incorporation of CNTs effectively improves the electrochemical performances of the GO/PEDOT electrodes. Long CNTs-incorporated GO/PEDOT-lCNTs electrodes have more superior electrochemical behaviors with respect to the short CNTs-incorporated GO/PEDOT-lCNTs electrodes, which can be attributed to the optimized composition and specific microstructures of the former. To verify the feasibility of the prepared composite electrodes for utilization as flexible supercapacitor, a solid-state supercapacitor using the CNFs-loaded GO/PEDOT-lCNTs electrodes is fabricated and tested. The device shows lightweight, ultrathin, and highly flexible features, which also has a high areal and volumetric specific capacitance (33.4 m F cm-2 at 10 mV s-1 and 2.7 F cm-3 at 0.042 A cm-3), superior rate capability, and excellent cycle stability (maintaining 97.5% for 5000 cycles). This highly flexible solid-state supercapacitor has great potential for applications in flexible electronics, roll-up display, and wearable devices.

  5. Electric terminal performance and characterization of solid oxide fuel cells and systems

    Science.gov (United States)

    Lindahl, Peter Allan

    Solid Oxide Fuel Cells (SOFCs) are electrochemical devices which can effect efficient, clean, and quiet conversion of chemical to electrical energy. In contrast to conventional electricity generation systems which feature multiple discrete energy conversion processes, SOFCs are direct energy conversion devices. That is, they feature a fully integrated chemical to electrical energy conversion process where the electric load demanded of the cell intrinsically drives the electrochemical reactions and associated processes internal to the cell. As a result, the cell's electric terminals provide a path for interaction between load side electric demand and the conversion side processes. The implication of this is twofold. First, the magnitude and dynamic characteristics of the electric load demanded of the cell can directly impact the long-term efficacy of the cell's chemical to electrical energy conversion. Second, the electric terminal response to dynamic loads can be exploited for monitoring the cell's conversion side processes and used in diagnostic analysis and degradation-mitigating control schemes. This dissertation presents a multi-tier investigation into this electric terminal based performance characterization of SOFCs through the development of novel test systems, analysis techniques and control schemes. First, a reference-based simulation system is introduced. This system scales up the electric terminal performance of a prototype SOFC system, e.g. a single fuel cell, to that of a full power-level stack. This allows realistic stack/load interaction studies while maintaining explicit ability for post-test analysis of the prototype system. Next, a time-domain least squares fitting method for electrochemical impedance spectroscopy (EIS) is developed for reduced-time monitoring of the electrochemical and physicochemical mechanics of the fuel cell through its electric terminals. The utility of the reference-based simulator and the EIS technique are demonstrated

  6. Impact of the electric compressor for automotive air conditioning system on fuel consumption and performance analysis

    Science.gov (United States)

    Zulkifli, A. A.; Dahlan, A. A.; Zulkifli, A. H.; Nasution, H.; Aziz, A. A.; Perang, M. R. M.; Jamil, H. M.; Misseri, M. N.

    2015-12-01

    Air conditioning system is the biggest auxiliary load in a vehicle where the compressor consumed the largest. Problem with conventional compressor is the cooling capacity cannot be control directly to fulfill the demand of thermal load inside vehicle cabin. This study is conducted experimentally to analyze the difference of fuel usage and air conditioning performance between conventional compressor and electric compressor of the air conditioning system in automobile. The electric compressor is powered by the car battery in non-electric vehicle which the alternator will recharge the battery. The car is setup on a roller dynamometer and the vehicle speed is varied at 0, 30, 60, 90 and 110 km/h at cabin temperature of 25°C and internal heat load of 100 and 400 Watt. The results shows electric compressor has better fuel consumption and coefficient of performance compared to the conventional compressor.

  7. Regenerated cellulose/multiwalled carbon nanotube composite films with efficient electric heating performance.

    Science.gov (United States)

    Lee, Tae-Won; Jeong, Young Gyu

    2015-11-20

    We have manufactured regenerated cellulose-based composite films reinforced with pristine multiwalled carbon nanotube (MWCNT) by a facile casting of cellulose/DMAc/LiCl solutions containing 0.2-10.0wt% MWCNT and have investigated their application as electric heating materials by examining microstructure, thermal stability, and electrical properties. TEM images showed that the pristine MWCNT was dispersed well in the regenerated cellulose matrix. The composite films were found to be stable thermally up to ∼275°C. The electrical resistivity of the regenerated cellulose/MWCNT composite films decreased significantly from ∼10(9)Ωcm to ∼10(1)Ωcm with increasing the MWCNT loading, particularly at a certain MWCNT content between 2.0 and 3.0wt%. Accordingly, the composite films with 5.0-10.0wt% MWCNT contents, which possessed low electrical resistivity of ∼10(2)-10(1)Ωcm, exhibited excellent electric heating performance in aspects of temperature responsiveness, steady-state maximum temperature, and electrical energy efficiency at constant applied voltages. For instance, the composite film with 10.0wt% MWCNT had well-controlled steady-state maximum temperatures of 40-189°C at 20-80V, characteristic temperature growth constant of ∼1s, and electric power efficiency of ∼5.4mW/°C, which performance remained unchanged under repeated experiments for several hours. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. High-performance electrically conductive silver paste prepared by silver-containing precursor

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jianguo; Cao, Yu; Li, Xiangyou; Wang, Xiaoye; Zeng, Xiaoyan [Huazhong University of Science and Technology, Wuhan National Laboratory for Optoelectronics, College of Optoelectronics Science and Engineering, Wuhan (China)

    2010-09-15

    A high-performance electrically conductive silver paste with no solid particles before drying and/or sintering is developed, in which silver-containing precursor is employed as conductive functional phase. Thermogravimetry analysis, volume electrical resistivity tests and sintering experiments show that the paste with about 14 wt.% silver pristine content is able to achieve the volume electrical resistivity of (2-3) x 10{sup -5} {omega} cm after it is sintered at 220 C. A micro-pen direct-writing process indicates that it is very suitable for the fabrication of high-resolution (25 {mu}m) and high-integration devices and apparatus. (orig.)

  9. High-performance electrically conductive silver paste prepared by silver-containing precursor

    Science.gov (United States)

    Liu, Jianguo; Cao, Yu; Li, Xiangyou; Wang, Xiaoye; Zeng, Xiaoyan

    2010-09-01

    A high-performance electrically conductive silver paste with no solid particles before drying and/or sintering is developed, in which silver-containing precursor is employed as conductive functional phase. Thermogravimetry analysis, volume electrical resistivity tests and sintering experiments show that the paste with about 14 wt.% silver pristine content is able to achieve the volume electrical resistivity of (2-3) ×10-5 Ω cm after it is sintered at 220°C. A micro-pen direct-writing process indicates that it is very suitable for the fabrication of high-resolution (25 μm) and high-integration devices and apparatus.

  10. Performance of Klebsiella oxytoca to generate electricity from POME in microbial fuel cell

    OpenAIRE

    Islam Md. Amirul; Rahman Maksudur; Yousuf Abu; Cheng Chin Kui; Wai Woon Chee

    2016-01-01

    This study is aimed to evaluate the electricity generation from microbial fuel cell (MFC) and to analyze the microbial community structure of city wastewater and anaerobic sludge to enhance the MFC performance. MFCs, enriched with palm oil mill effluent (POME) were employed to harvest electricity by innoculating of Klebsiella oxytoca, collected from city wastewater and other microbes from anaerobic sludge (AS). The MFC showed maximum power density of 207.28 mW/m3 with continuous feeding of PO...

  11. A Method For Determination And Standardization Of Performance Parameters For Aircrafts With Electric Drives

    Directory of Open Access Journals (Sweden)

    Jakielaszek Zbigniew

    2014-12-01

    Full Text Available The study outlines the technique for flight tests carried out for a plane powered by an electric drive and the method for standardization of performance parameters applicable to evaluation of test results. Due to the relatively new type of drive, which is an electric motor, the literature references provide no descriptions of such issues. Therefore the solutions presented in the paper are the own contribution of the research team from Air Force Institute of Technology (ITWL.

  12. Coaxial electrospinning of WO3 nanotubes functionalized with bio-inspired Pd catalysts and their superior hydrogen sensing performance

    Science.gov (United States)

    Choi, Seon-Jin; Chattopadhyay, Saptarshi; Kim, Jae Jin; Kim, Sang-Joon; Tuller, Harry L.; Rutledge, Gregory C.; Kim, Il-Doo

    2016-04-01

    Macroporous WO3 nanotubes (NTs) functionalized with nanoscale catalysts were fabricated using coaxial electrospinning combined with sacrificial templating and protein-encapsulated catalysts. The macroporous thin-walled nanotubular structures were obtained by introducing colloidal polystyrene (PS) particles to a shell solution of W precursor and poly(vinylpyrrolidone). After coaxial electrospinning with a core liquid of mineral oil and subsequent calcination, open pores with an average diameter of 173 nm were formed on the surface of WO3 NTs due to decomposition of the PS colloids. In addition, catalytic Pd nanoparticles (NPs) were synthesized using bio-inspired protein cages, i.e., apoferritin, and uniformly dispersed within the shell solution and subsequently on the WO3 NTs. The resulting Pd functionalized macroporous WO3 NTs were demonstrated to be high performance hydrogen (H2) sensors. In particular, Pd-functionalized macroporous WO3 NTs exhibited a very high H2 response (Rair/Rgas) of 17.6 at 500 ppm with a short response time. Furthermore, the NTs were shown to be highly selective for H2 compared to other gases such as carbon monoxide (CO), ammonia (NH3), and methane (CH4). The results demonstrate a new synthetic method to prepare highly porous nanotubular structures with well-dispersed nanoscale catalysts, which can provide improved microstructures for chemical sensing.Macroporous WO3 nanotubes (NTs) functionalized with nanoscale catalysts were fabricated using coaxial electrospinning combined with sacrificial templating and protein-encapsulated catalysts. The macroporous thin-walled nanotubular structures were obtained by introducing colloidal polystyrene (PS) particles to a shell solution of W precursor and poly(vinylpyrrolidone). After coaxial electrospinning with a core liquid of mineral oil and subsequent calcination, open pores with an average diameter of 173 nm were formed on the surface of WO3 NTs due to decomposition of the PS colloids. In addition

  13. Multivariate economic performance assessment of an MPC controlled electric arc furnace.

    Science.gov (United States)

    Wei, Donghui; Craig, Ian K; Bauer, Margret

    2007-06-01

    Economic performance is very important to advanced process control projects investigating whether the investment of control technology is worthwhile. In this paper economic performance assessment of a simulated electric arc furnace is conducted. The dependence of controlled variables and the corresponding economic impact are highlighted.

  14. Performance evaluation of three-phase electric motors; Avaliacao do desempenho de motores eletricos trifasicos

    Energy Technology Data Exchange (ETDEWEB)

    Burgoa, Jaime Antonio; Simoes, Nelson Wander Beirao [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil); Cogo, Joao Roberto [Escola Federal de Engenharia de Itajuba, MG (Brazil)

    1993-12-31

    Tests and analysis of performance to the electric generators made by Brazilian industry, is related. The tests program was developed in the Escola Federal de Engenharia de Itajuba under the patronage of Programa Nacional de Conservacao de energia Eletrica. The results of tests,the parameters which define the performance of these motors, are also showed 8 refs., 6 tabs.

  15. Economic Comparison of Electric Vehicles Performing Unidirectional and Bidirectional Frequency Control in Denmark with Practical Validation

    DEFF Research Database (Denmark)

    Thingvad, Andreas; Martinenas, Sergejus; Andersen, Peter Bach

    2016-01-01

    the EV is plugged into the network ready to support the system frequency. Performing unidirectional frequency control with Electric Vehicles (EVs) requires little hardware implementation in the household but has the limit that the service only can be performed until the battery is fully charged...

  16. A Cochlear Implant Performance Prognostic Test Based on Electrical Field Interactions Evaluated by eABR (Electrical Auditory Brainstem Responses.

    Directory of Open Access Journals (Sweden)

    Nicolas Guevara

    Full Text Available Cochlear implants (CIs are neural prostheses that have been used routinely in the clinic over the past 25 years. They allow children who were born profoundly deaf, as well as adults affected by hearing loss for whom conventional hearing aids are insufficient, to attain a functional level of hearing. The "modern" CI (i.e., a multi-electrode implant using sequential coding strategies has yielded good speech comprehension outcomes (recognition level for monosyllabic words about 50% to 60%, and sentence comprehension close to 90%. These good average results however hide a very important interindividual variability as scores in a given patients' population often vary from 5 to 95% in comparable testing conditions. Our aim was to develop a prognostic model for patients with unilateral CI. A novel method of objectively measuring electrical and neuronal interactions using electrical auditory brainstem responses (eABRs is proposed.The method consists of two measurements: 1 eABR measurements with stimulation by a single electrode at 70% of the dynamic range (four electrodes distributed within the cochlea were tested, followed by a summation of these four eABRs; 2 Measurement of a single eABR with stimulation from all four electrodes at 70% of the dynamic range. A comparison of the eABRs obtained by these two measurements, defined as the monaural interaction component (MIC, indicated electrical and neural interactions between the stimulation channels. Speech recognition performance without lip reading was measured for each patient using a logatome test (64 "vowel-consonant-vowel"; VCV; by forced choice of 1 out of 16. eABRs were measured in 16 CI patients (CIs with 20 electrodes, Digisonic SP; Oticon Medical ®, Vallauris, France. Significant correlations were found between speech recognition performance and the ratio of the amplitude of the V wave of the eABRs obtained with the two measurements (Pearson's linear regression model, parametric correlation: r

  17. Fabrication and magnetic-induced aggregation of Fe{sub 3}O{sub 4}–noble metal composites for superior SERS performances

    Energy Technology Data Exchange (ETDEWEB)

    Gan, Zibao; Zhao, Aiwu, E-mail: awzhao@iim.ac.cn; Zhang, Maofeng; Wang, Dapeng; Guo, Hongyan; Tao, Wenyu; Gao, Qian; Mao, Ranran; Liu, Erhu [Chinese Academy of Sciences, Institute of Intelligent Machines (China)

    2013-11-15

    Fe{sub 3}O{sub 4}–noble metal composites were obtained by combining Au, Ag nanoparticles (NPs) with 3-aminopropyltrimethoxysilane-functionalized Fe{sub 3}O{sub 4} NPs. UV–Visible absorption spectroscopy demonstrates the obtained Fe{sub 3}O{sub 4}–noble metal composites inherit the typical surface plasmon resonance bands of Au, Ag at 533 and 453 nm, respectively. Magnetic measurements also indicated that the superparamagnetic Fe{sub 3}O{sub 4}–noble metal composites have excellent magnetic response behavior. A magnetic-induced idea was introduced to change their aggregated states and take full advantage of their surface-enhanced Raman scattering (SERS) performances. Under the induction of an external magnetic field, the bifunctional Fe{sub 3}O{sub 4}–noble metal aggregates exhibit the unique superiority in SERS detection of Rhodamine 6G (R6G), compared with the naturally dispersed Au, Ag NPs. Especially, the detection limit of the Fe{sub 3}O{sub 4}–Ag aggregates for R6G is as low as 10{sup −14} M, and the calculated EF reaches up to 1.2 × 10{sup 6}, which meets the requirements for trace detection of analytes. Furthermore, the superiority could be extended to sensitive detection of other organic molecules, such as 4-mercaptopyridine. This work provides a new insight for active adjustment of the aggregated states of SERS substrates and the optimization of SERS performances.

  18. Cooling Performance Characteristics on Mobile Air-Conditioning System for Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Ho-Seong Lee

    2013-01-01

    Full Text Available This study investigates the cooling performance characteristics of the mobile air-conditioning system using R744 (CO2 for the hybrid electric vehicle as an alternative to both the R-134a and the conventional air-conditioning system. The developed air-conditioning system is operated with an electric driven compressor in the battery driving mode and a belt driven compressor in the engine driving mode. The cooling performance characteristics of the developed system have been analyzed by experiments under various operating conditions of inlet air temperature, air flow rates for the gas cooler side and evaporator side, and electric compressor revolution respectively. As a result, cooling performances of the tested air-conditioning system for the EDC driving mode (electricity driven compressor were better than those for the BDC driving mode (belt driven compressor. The cooling capacity and cooling COP of the tested air-conditioning system for both driving modes were over 5.0 kW and 2.0, respectively. The observed cooling performance of the tested air-conditioning system may be sufficient for the cabin cooling of hybrid electric vehicles.

  19. Steering Dynamic Performance of an Electric Transmission Tracked Vehicle Based on Rotating Speed Control

    Institute of Scientific and Technical Information of China (English)

    SUN Feng-chun; CHEN Shu-yong; ZHANG Cheng-ning

    2006-01-01

    In order to analyze steering dynamic performance of an electric transmission tracked vehicle exactly, modern design theory and methodology-collaborative simulation and virtual prototype are applied. The 3-D multi-body dynamic model of full vehicle running gears and control system model are built based on the simulation platform on dynamic analysis software known as RecurDyn/Track-HM and control system analysis software known as Matlab/Simulink. Theory analysis and collaborative simulation of turning kinematic/dynamic performance in different velocity and turning radius are made. Comparing the test result with theory computation validates the correctness of the model. The method has instructional significance of solving the existent modeling problem, comprehension of turning performance and test debugging strategy,and also forms a new idea of research on dynamic characteristics for the electric transmission tracked vehicle's electric propulsion system.

  20. A Novel Dual-Electrode Plug to Achieve Intensive Electric Field for High Performance Ignition

    Directory of Open Access Journals (Sweden)

    Chih-Lung Shen

    2013-01-01

    Full Text Available A thorough analysis of electric field is carried out so as to verify that a novel dual-electrode plug can build intensive electric field and can improve the main drawbacks of feeble electric field and low ignition efficiency of the traditional plug. With intensive electric field, the proposed novel plug can achieve high performance ignition, resulting in fuel saving and exhaust reduction. Gauss law is applied for electric field analysis to show that intensive electric field can be built by the novel plug. Then, according to Faraday law a lower-voltage ignition feature accomplished by the plug is discussed. Compared with traditional plug, the novel dual-electrode plug has the following advantages. (1 Much higher energy density is built between the plug electrodes, lowering ignition voltage requirement. (2 Electromagnetic interference (EMI problem caused by high ignition voltage is readily resolved. (3 Ignition time delay can be improved. (4 The feature to save fuel consuming is achieved. (5 The exhaust of CO and HC is reduced significantly. Practical measurements are fulfilled to validate the electric field analysis and to demonstrate the features of the proposed dual-electrode plug.

  1. Performance of fuzzy approach in Malaysia short-term electricity load forecasting

    Science.gov (United States)

    Mansor, Rosnalini; Zulkifli, Malina; Yusof, Muhammad Mat; Ismail, Mohd Isfahani; Ismail, Suzilah; Yin, Yip Chee

    2014-12-01

    Many activities such as economic, education and manafucturing would paralyse with limited supply of electricity but surplus contribute to high operating cost. Therefore electricity load forecasting is important in order to avoid shortage or excess. Previous finding showed festive celebration has effect on short-term electricity load forecasting. Being a multi culture country Malaysia has many major festive celebrations such as Eidul Fitri, Chinese New Year and Deepavali but they are moving holidays due to non-fixed dates on the Gregorian calendar. This study emphasis on the performance of fuzzy approach in forecasting electricity load when considering the presence of moving holidays. Autoregressive Distributed Lag model was estimated using simulated data by including model simplification concept (manual or automatic), day types (weekdays or weekend), public holidays and lags of electricity load. The result indicated that day types, public holidays and several lags of electricity load were significant in the model. Overall, model simplification improves fuzzy performance due to less variables and rules.

  2. Oriented graphene films for use as high-performance thermal and electrical interconnects

    Science.gov (United States)

    Moafi, Ali; Wong, Kevin; Lau, Desmond; Partridge, Jim G.; McCulloch, Dougal G.

    2008-12-01

    Carbon thin films can be prepared with properties that make them suitable for applications in electronics including heat sinks, electrical interconnects transistors and chemical sensors. In this work, we examine the microstructure and normalised through film electrical resistance of oriented and non-oriented carbon films deposited onto silicon substrates at room temperature using a Filtered Cathodic Vacuum Arc (FCVA). Electrical measurements have also been performed on carbon films which were lithographically patterned to produce test structures resembling vertical interconnects. Twopoint, through-film current-voltage measurements of NiCr/Carbon/Si structures showed that the electrical resistance of the carbon films could be varied by several orders of magnitude simply by selecting different substrate bias voltages. Importantly, carbon films composed of vertically aligned graphene sheets were found to provide low resistance, linear current-voltage characteristics, indicating the formation of Ohmic junctions at the NiCr and Si interfaces of the NiCr/Carbon/Si structure.

  3. Dimensional heterostructures of 1D CdS/2D ZnIn2S4 composited with 2D graphene: designed synthesis and superior photocatalytic performance.

    Science.gov (United States)

    Tian, Qingyong; Wu, Wei; Liu, Jun; Wu, Zhaohui; Yao, Weijing; Ding, Jin; Jiang, Changzhong

    2017-02-28

    The development of photocatalysts with superior photoactivity and stability for the degradation of organic dyes is very important for environmental remediation. In this study, we have presented a multidimensional (1D and 2D) structured CdS/ZnIn2S4/RGO photocatalyst with superior photocatalytic performance. The CdS/ZnIn2S4 helical dimensional heterostructures (DHS) were prepared via a facile solvothermal synthesis method to facilitate the epitaxial growth of 2D ZnIn2S4 nanosheets on 1D CdS nanowires. Ultrathin 2D ZnIn2S4 nanosheets have grown uniformly and perpendicular to the surface of 1D CdS nanowires. The as-obtained 1D/2D CdS/ZnIn2S4 helical DHS show good photocatalytic properties for malachite green (MG). Subsequently, 2D reduced graphene oxide (RGO) was introduced into the 1D/2D CdS/ZnIn2S4 helical DHS as a co-catalyst. The photoactivity and stability of the CdS/ZnIn2S4/RGO composites are significantly improved after 6 cycles. The enhanced photoactivity can be attributed to the high surface area of RGO, the improved adsorption of organic dyes and the efficient spatial separation of photo-induced charge carriers. The transfer of photo-generated electrons from the interface of CdS and ZnIn2S4 to RGO also restricted the photocorrosion of metal sulfide, suggesting an improved stability of the reused CdS/ZnIn2S4/RGO composited photocatalyst.

  4. A novel high-performance high-frequency SOI MESFET by the damped electric field

    Science.gov (United States)

    Orouji, Ali A.; Khayatian, Ahmad; Keshavarzi, Parviz

    2016-06-01

    In this paper, we introduce a novel silicon-on-insulator (SOI) metal-semiconductor field-effect-transistor (MESFET) using the damped electric field (DEF). The proposed structure is geometrically symmetric and compatible with common SOI CMOS fabrication processes. It has two additional oxide regions under the side gates in order to improve DC and RF characteristics of the DEF structure due to changes in the electrical potential, the electrical field distributions, and rearrangement of the charge carriers. Improvement of device performance is investigated by two-dimensional and two-carrier simulation of fundamental parameters such as breakdown voltage (VBR), drain current (ID), output power density (Pmax), transconductance (gm), gate-drain and gate-source capacitances, cut-off frequency (fT), unilateral power gain (U), current gain (h21), maximum available gain (MAG), and minimum noise figure (Fmin). The results show that proposed structure operates with higher performances in comparison with the similar conventional SOI structure.

  5. Improving the electrical performance of MoS2 by mild oxygen plasma treatment

    Science.gov (United States)

    Nan, Haiyan; Wu, Zhangting; Jiang, Jie; Zafar, Amina; You, Yumeng; Ni, Zhenhua

    2017-04-01

    Two-dimensional (2D) molybdenum disulfide (MoS2) is considered as a promising candidate for electronic and optoelectronic devices. However, structural defects in MoS2 are widely reported and can greatly degrade its electrical and optical properties. In this work, we investigate the structural defects in MoS2 by low temperature photoluminescence (PL) spectroscopy and study their effects on the electrical performance, i.e. carrier mobility. We also adopt the mild oxygen plasma treatment to repair the structural defects and found that the carrier mobility of monolayer MoS2 can be greatly improved. This work would therefore offer a practical route to improve the performance of 2D dichalcogenide-based electrical and optoelectronic devices.

  6. A novel graphene nanoribbon FET with an extra peak electric field (EFP-GNRFET) for enhancing the electrical performances

    Science.gov (United States)

    Akbari Eshkalak, Maedeh; Anvarifard, Mohammad K.

    2017-04-01

    This work has provided an efficient technique to improve the electrical performance for the Graphene Nanoribbon Field Effect Transistors (GNRFETs) successfully. The physical gate length is divided into two gates named as the original gate and the other one as the virtual gate. We have applied a voltage source between these gates to control the channel of the GNRFETs. This technique has created an extra peak electric field in the middle of the channel resulting in the redistribution of surface potential profile. The proposed structure named as EFP-GNRFET has been compared with a simple GNRFET and has shown many improvements in terms of the critical parameters such as short channel effects, leakage current, subthreshold swing, ON-state to OFF-state current ratio, transconductance, output conductance and voltage gain. The structures under the study in this paper benefits from the Non-Equilibrium Green Function (NEGF) approach for solving Schrödinger equation coupled with the two-dimensional (2D) Poisson equation in a self-consistent manner.

  7. Superior Light-Harvesting Heteroleptic Ruthenium(II) Complexes with Electron-Donating Antennas for High Performance Dye-Sensitized Solar Cells.

    Science.gov (United States)

    Chen, Wang-Chao; Kong, Fan-Tai; Li, Zhao-Qian; Pan, Jia-Hong; Liu, Xue-Peng; Guo, Fu-Ling; Zhou, Li; Huang, Yang; Yu, Ting; Dai, Song-Yuan

    2016-08-03

    Three heteroleptic polypyridyl ruthenium complexes, RC-41, RC-42, and RC-43, with efficient electron-donating antennas in the ancillary ligands were designed, synthesized, and characterized as sensitizers for dye-sensitized solar cell. All the RC dye sensitizers showed remarkable light-harvesting capacity and broadened absorption range. Significantly, RC-43 obtained the lower energy metal-ligand charge transfer (MLCT) band peaked at 557 nm with a high molar extinction coefficient of 27 400 M(-1) cm(-1). In conjunction with TiO2 photoanode of submicrospheres and iodide-based electrolytes, the DSSCs sensitizing with the RC sensitizers, achieved impressively high short-circuit current density (19.04 mA cm(-2) for RC-41, 19.83 mA cm(-2) for RC-42, and 20.21 mA cm(-2) for RC-43) and power conversion efficiency (10.07% for RC-41, 10.52% for RC-42, and 10.78% for RC-43). The superior performances of RC dye sensitizers were attributed to the enhanced light-harvesting capacity and incident-photon-to-current efficiency (IPCE) caused by the introduction of electron-donating antennas in the ancillary ligands. The interfacial charge recombination/regeneration kinetics and electron lifetime were further evaluated by the electrochemical impedance spectroscopy (EIS) and transient absorption spectroscopy (TAS). These data decisively revealed the dependences on the photovoltaic performance of ruthenium sensitizers incorporating electron-donating antennas.

  8. One-step solvothermal deposition of ZnO nanorod arrays on a wood surface for robust superamphiphobic performance and superior ultraviolet resistance

    Science.gov (United States)

    Yao, Qiufang; Wang, Chao; Fan, Bitao; Wang, Hanwei; Sun, Qingfeng; Jin, Chunde; Zhang, Hong

    2016-01-01

    In the present paper, uniformly large-scale wurtzite-structured ZnO nanorod arrays (ZNAs) were deposited onto a wood surface through a one-step solvothermal method. The as-prepared samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG), and differential thermal analysis (DTA). ZNAs with a diameter of approximately 85 nm and a length of approximately 1.5 μm were chemically bonded onto the wood surface through hydrogen bonds. The superamphiphobic performance and ultraviolet resistance were measured and evaluated by water or oil contact angles (WCA or OCA) and roll-off angles, sand abrasion tests and an artificially accelerated ageing test. The results show that the ZNA-treated wood demonstrates a robust superamphiphobic performance under mechanical impact, corrosive liquids, intermittent and transpositional temperatures, and water spray. Additionally, the as-prepared wood sample shows superior ultraviolet resistance. PMID:27775091

  9. One-step solvothermal deposition of ZnO nanorod arrays on a wood surface for robust superamphiphobic performance and superior ultraviolet resistance

    Science.gov (United States)

    Yao, Qiufang; Wang, Chao; Fan, Bitao; Wang, Hanwei; Sun, Qingfeng; Jin, Chunde; Zhang, Hong

    2016-10-01

    In the present paper, uniformly large-scale wurtzite-structured ZnO nanorod arrays (ZNAs) were deposited onto a wood surface through a one-step solvothermal method. The as-prepared samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG), and differential thermal analysis (DTA). ZNAs with a diameter of approximately 85 nm and a length of approximately 1.5 μm were chemically bonded onto the wood surface through hydrogen bonds. The superamphiphobic performance and ultraviolet resistance were measured and evaluated by water or oil contact angles (WCA or OCA) and roll-off angles, sand abrasion tests and an artificially accelerated ageing test. The results show that the ZNA-treated wood demonstrates a robust superamphiphobic performance under mechanical impact, corrosive liquids, intermittent and transpositional temperatures, and water spray. Additionally, the as-prepared wood sample shows superior ultraviolet resistance.

  10. N-doped graphene layers encapsulated NiFe alloy nanoparticles derived from MOFs with superior electrochemical performance for oxygen evolution reaction

    Science.gov (United States)

    Feng, Yi; Yu, Xin-Yao; Paik, Ungyu

    2016-01-01

    Water splitting, an efficient approach for hydrogen production, is often hindered by unfavorable kinetics of oxygen evolution reaction (OER). In order to reduce the overpotential, noble metal oxides-based electrocatalysts like RuO2 and IrO2 are usually utilized. However, due to their scarcity, the development of cost-effective non-precious OER electrocatalysts with high efficiency and good stability is urgently required. Herein, we report a facile one-step annealing of metal-organic frameworks (MOFs) strategy to synthesize N-doped graphene layers encapsulated NiFe alloy nanoparticles (NiFe@C). Through tuning the nanoparticle size and calcination temperature, NiFe@C with an average size of around 16 nm obtained at 700 °C exhibits superior OER performance with an overpotential of only 281 mV at 10 mA cm−2 and high durability. The facile synthesis method and excellent electrochemical performance show great potential of NiFe@C in replacing the precious metal-based electrocatalysts in the OER. PMID:27658968

  11. Performance of Batteries for electric vehicles on shorter and longer term

    NARCIS (Netherlands)

    Gerssen-Gondelach, S.J.; Faaij, A.P.C.

    2012-01-01

    In this work, the prospects of available and new battery technologies for battery electric vehicles (BEVs) are examined. Five selected battery technologies are assessed on battery performance and cost in the short, medium and long term. Driving cycle simulations are carried out to assess the influen

  12. Performance of batteries for electric vehicles on short and longer term

    NARCIS (Netherlands)

    Gerssen - Gondelach, Sarah|info:eu-repo/dai/nl/355262436; Faaij, André P C|info:eu-repo/dai/nl/10685903X

    2012-01-01

    In this work, the prospects of available and new battery technologies for battery electric vehicles (BEVs) are examined. Five selected battery technologies are assessed on battery performance and cost in the short, medium and long term. Driving cycle simulations are carried out to assess the influen

  13. Effect of Polya Problem-Solving Model on Senior Secondary School Students' Performance in Current Electricity

    Science.gov (United States)

    Olaniyan, Ademola Olatide; Omosewo, Esther O.; Nwankwo, Levi I.

    2015-01-01

    This study was designed to investigate the Effect of Polya Problem-Solving Model on Senior School Students' Performance in Current Electricity. It was a quasi experimental study of non- randomized, non equivalent pre-test post-test control group design. Three research questions were answered and corresponding three research hypotheses were tested…

  14. Performance of Batteries for electric vehicles on shorter and longer term

    NARCIS (Netherlands)

    Gerssen-Gondelach, S.J.; Faaij, A.P.C.

    2012-01-01

    In this work, the prospects of available and new battery technologies for battery electric vehicles (BEVs) are examined. Five selected battery technologies are assessed on battery performance and cost in the short, medium and long term. Driving cycle simulations are carried out to assess the influen

  15. Performance of batteries for electric vehicles on short and longer term

    NARCIS (Netherlands)

    Gerssen - Gondelach, Sarah; Faaij, André P C

    2012-01-01

    In this work, the prospects of available and new battery technologies for battery electric vehicles (BEVs) are examined. Five selected battery technologies are assessed on battery performance and cost in the short, medium and long term. Driving cycle simulations are carried out to assess the influen

  16. Electrical resistivity testing for as-built concrete performance assessment of chloride penetration resistance

    NARCIS (Netherlands)

    Polder, R.B.; Peelen, W.H.A.

    2014-01-01

    The electrical resistivity of concrete can provide information about its transport properties, which is relevant for durability performance. For example, resistivity is inversely proportional to chloride diffusion, at least within similar concrete compositions. A methodology is proposed for on-site

  17. Performance of batteries for electric vehicles on short and longer term

    NARCIS (Netherlands)

    Gerssen - Gondelach, Sarah|info:eu-repo/dai/nl/355262436; Faaij, André P C|info:eu-repo/dai/nl/10685903X

    2012-01-01

    In this work, the prospects of available and new battery technologies for battery electric vehicles (BEVs) are examined. Five selected battery technologies are assessed on battery performance and cost in the short, medium and long term. Driving cycle simulations are carried out to assess the

  18. Performance of Batteries for electric vehicles on shorter and longer term

    NARCIS (Netherlands)

    Gerssen-Gondelach, S.J.; Faaij, A.P.C.

    2012-01-01

    In this work, the prospects of available and new battery technologies for battery electric vehicles (BEVs) are examined. Five selected battery technologies are assessed on battery performance and cost in the short, medium and long term. Driving cycle simulations are carried out to assess the

  19. [Electricity generation and contaminants degradation performances of a microbial fuel cell fed with Dioscorea zingiberensis wastewater].

    Science.gov (United States)

    Li, Hui; Zhu, Xiu-Ping; Xu, Nan; Ni, Jin-Ren

    2011-01-01

    The electricity generation performance of a microbial fuel cell (MFC) utilizing Dioscorea zingiberensis wastewater was studied with an H-shape reactor. Indexes including pH, conductivity, oxidation peak potential and chemical oxygen demand (COD) of the anolyte were monitored to investigate the contaminants degradation performance of the MFC during the electricity generation process, besides, contaminant ingredients in anodic influent and effluent were analyzed by GC-MS and IR spectra as well. The maximum power density of the MFC could achieve 118.1 mW/m2 and the internal resistance was about 480 omega. Connected with a 1 000 omega external resistance, the output potential was about 0.4 V. Fed with 5 mL Dioscorea zingiberensis wastewater, the electricity generation lasted about 133 h and the coulombic efficiency was about 3.93%. At the end of electricity generation cycle, COD decreased by 90.1% while NH4(+) -N decreased by 66.8%. Furfural compounds, phenols and some other complicated organics could be decomposed and utilized in the electricity generation process, and the residual contaminants in effluent included some long-chain fatty acids, esters, ethers, and esters with benzene ring, cycloalkanes, cycloolefins, etc. The results indicate that MFC, which can degrade and utilize the organic contaminants in Dioscorea zingiberensis wastewater simultaneously, provides a new approach for resource recovery treatment of Dioscorea zingiberensis wastewater.

  20. Carboplatin plus pemetrexed offers superior cost-effectiveness compared to pemetrexed in patients with advanced non-small cell lung cancer and performance status 2.

    Science.gov (United States)

    Schluckebier, Luciene; Garay, Osvaldo U; Zukin, Mauro; Ferreira, Carlos G

    2015-09-01

    Pemetrexed plus carboplatin offers survival advantage in first line treatment of advanced lung cancer patients with performance status of 2. We estimated the cost-effectiveness of this combined regimen compared to pemetrexed alone in a Brazilian population. A cost-effectiveness analysis was conducted based on a randomized phase III trial in patients with advanced non-small cell lung cancer (NSCLC) and ECOG performance status of 2 (PS2), comparing doublet regimen pemetrexed plus carboplatin with pemetrexed alone. The perspective adopted was the public health care sector over a three-year period. Direct medical costs and survival time were calculated from patient-level data and utility values were extracted from the literature. Sensitivity analyses were performed to evaluate uncertainties in the results. The combined regimen pemetrexed plus carboplatin yielded a gain of 0.16 life year (LY) and 0.12 quality-adjusted life year (QALY) compared to pemetrexed alone. The total cost was 17,674.31 USD for the combined regimen and 15,722.39 USD for pemetrexed alone. The incremental cost-effectiveness ratio (ICER) was $12,016.09 per LY gained and $15,732.05 per QALY gained. The factors with the greatest impact on the ICER are pemetrexed price and the time to progression utility value. The cost-effectiveness acceptability curve showed an upper 90% probability of pemetrexed plus carboplatin being cost-effective with a threshold between two and three GDP per capita. Our study suggests superiority of the combined pemetrexed plus carboplatin regimen in terms of efficacy as well as cost-effectiveness in advanced NSCLC patients with a poor performance status of 2. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  1. Electric vehicles performance estimation through a patterns extraction and classification methodology

    Science.gov (United States)

    Barré, Anthony; Suard, Frédéric; Gérard, Mathias; Riu, Delphine

    2015-01-01

    Direct estimation of battery performance is a major challenge as ageing process is a complex phenomenon not directly measurable. In this work a new methodology is provided to estimate global battery performances under real-life electric vehicle use. Such performances are estimated through battery signals patterns extraction. These signals patterns are used to identify physical degradation behavior of batteries. The analysis framework is composed of patterns extraction, clustering algorithms, summarizing data representation in the feature space of cluster distances and classification algorithms. This methodology is then applied on datasets, acquired from batteries used on electric vehicles, without controlled environmental conditions. The classification algorithm accuracy is studied on the obtained real data. The results suggest that battery signals patterns analysis provides an innovative technique for online estimation of the battery performance level. A detection of dysfunctions caused by ageing is also made, only based on battery signals pattern extracted during real vehicle accelerations.

  2. Performance evaluation of high-temperature superconducting current leads for electric utility SMES systems

    Science.gov (United States)

    Niemann, R. C.; Cha, Y. S.; Hull, J. R.; Rey, C. M.; Dixon, K. D.

    As part of the U.S. Department of Energy's Superconductivity Technology Program, Argonne National Laboratory and Babcock & Wilcox are developing high-temperature super-conductor (HTS) current leads for application to electric utility superconducting magnetic energy storage systems. A 16,000-A HTS lead has been designed and is being constructed. An evaluation program for component performance was conducted to confirm performance predictions and/or to qualify the design features for construction. Performance of the current lead assemblies will be evaluated in a test program that includes assembly procedures, tooling, and quality assurance; thermal and electrical performance; and flow and mechanical characteristics. Results of the evaluations to date are presented.

  3. Sustainability Performance of Scandinavian Corporations and their Value Chains assessed by UN Global Compact and Global Reporting Initiative standards - a way to identify superior performers?

    DEFF Research Database (Denmark)

    Kjærgaard, Thomas

    2014-01-01

    Strategies & Policies, Management Systems, Monitoring and Evaluation Mechanisms and Key Outcomes on sustainability defined broadly as the Human Rights, Labour, Environment and Anti-Corruption issues by the UN Global Compact. The study firmly concludes that Scandinavian corporations on average......The purpose of this study was to introduce a combination of the two most adopted multi- stakeholder standards for sustainability reporting as an alternate framework for assessing sustainability performance in Scandinavian corporations. This novel approach leverages numeric measures on the criteria...... are not performing on higher levels concerning their implementation of these issues. The generalization of the results is moderated by the study's limitations concerning the framework and data sources used, sample size and the indirect use of GRI indicators. The uniqueness of the sustainability practice by two...

  4. 78 FR 21116 - Superior Supplier Incentive Program

    Science.gov (United States)

    2013-04-09

    ... Department of the Navy Superior Supplier Incentive Program AGENCY: Department of the Navy, DoD. ACTION... policy that will establish a Superior Supplier Incentive Program (SSIP). Under the SSIP, contractors that..., performance, quality, and business relations would be granted Superior Supplier Status (SSS). Contractors...

  5. Performance benchmarking and incentive regulation. Considerations of directing signals for electricity distribution companies

    Energy Technology Data Exchange (ETDEWEB)

    Honkapuro, S.

    2008-07-01

    After the restructuring process of the power supply industry, which for instance in Finland took place in the mid-1990s, free competition was introduced for the production and sale of electricity. Nevertheless, natural monopolies are found to be the most efficient form of production in the transmission and distribution of electricity, and therefore such companies remained franchised monopolies. To prevent the misuse of the monopoly position and to guarantee the rights of the customers, regulation of these monopoly companies is required. One of the main objectives of the restructuring process has been to increase the cost efficiency of the industry. Simultaneously, demands for the service quality are increasing. Therefore, many regulatory frameworks are being, or have been, reshaped so that companies are provided with stronger incentives for efficiency and quality improvements. Performance benchmarking has in many cases a central role in the practical implementation of such incentive schemes. Economic regulation with performance benchmarking attached to it provides companies with directing signals that tend to affect their investment and maintenance strategies. Since the asset lifetimes in the electricity distribution are typically many decades, investment decisions have far-reaching technical and economic effects. This doctoral thesis addresses the directing signals of incentive regulation and performance benchmarking in the field of electricity distribution. The theory of efficiency measurement and the most common regulation models are presented. The chief contributions of this work are (1) a new kind of analysis of the regulatory framework, so that the actual directing signals of the regulation and benchmarking for the electricity distribution companies are evaluated, (2) developing the methodology and a software tool for analysing the directing signals of the regulation and benchmarking in the electricity distribution sector, and (3) analysing the real

  6. Characteristic Evaluation on the Cooling Performance of an Electrical Air Conditioning System Using R744 for a Fuel Cell Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Moo-Yeon Lee

    2012-05-01

    Full Text Available The objective of this study was to investigate the cooling performance characteristics of an electrical air conditioning system using R744 as an alternative of R-134a for a fuel cell electric vehicle. In order to analyze the cooling performance characteristics of the air conditioning system using R744 for a fuel cell electric vehicle, an electrical air conditioning system using R744 was developed and tested under various operating conditions according to both inlet air conditions of the gas cooler and evaporator and compressor speed. The cooling capacity and coefficient of performance (COP forcooling of the tested air conditioning system were up to 6.4 kW and 2.5, respectively. In addition, the electrical air conditioning system with R744 using an inverter driven compressor showed better performance than the conventional air conditioning system with R-134a under the same operating conditions. The observed cooling performance of the developed electrical air conditioning system was found to be sufficient for cooling loads under various real driving conditions for a fuel cell electric vehicle.

  7. Environmental assessment for the electric and hybrid vehicle demonstration project, performance standards and financial incentives

    Energy Technology Data Exchange (ETDEWEB)

    LaBelle, S. J.

    1978-10-01

    The assessment is concerned with the impacts of the demonstration of electric and hybrid vehicles acquired to fulfill certain requirements of the Electric and Hybrid Vehicle Research, Development, and Demonstration Act, PL 94-413 as amended. The financial incentives programs and vehicle performance standards associated with the demonstration are also covered. Not included is an assessment of the long term effects of EHV commercialization and of the research and development program being carried out simultaneously with the demonstration, also in response to PL 94-413. These federal actions will be included in a programmatic environmental assessment scheduled for completion in FY 79.

  8. On the road performance tests of electric test vehicle for correlation with road load simulator

    Science.gov (United States)

    Dustin, M. O.; Slavik, R. J.

    1982-08-01

    A dynamometer (road load simulator) is used to test and evaluate electric vehicle propulsion systems. To improve correlation between system tests on the road load simulator and on the road, similar performance tests are conducted using the same vehicle. The results of track tests on the electric propulsion system test vehicle are described. The tests include range at constant speeds and over SAE J227a driving cycles, maximum accelerations, maximum gradability, and tire rolling resistance determination. Road power requirements and energy consumption were also determined from coast down tests.

  9. Renewable Power Options for Electrical Generation on Kaua'i: Economics and Performance Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Burman, K.; Keller, J.; Kroposki, B.; Lilienthal, P.; Slaughter, R.; Glassmire, J.

    2011-11-01

    The Hawaii Clean Energy Initiative (HCEI) is working with a team led by the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) to assess the economic and technical feasibility of increasing the contribution of renewable energy in Hawaii. This part of the HCEI project focuses on working with Kaua'i Island Utility Cooperative (KIUC) to understand how to integrate higher levels of renewable energy into the electric power system of the island of Kaua'i. NREL partnered with KIUC to perform an economic and technical analysis and discussed how to model PV inverters in the electrical grid.

  10. Life cycle environmental performance of miscanthus gasification versus other technologies for electricity production

    DEFF Research Database (Denmark)

    Nguyen, T Lan T; Hermansen, John Erik

    2015-01-01

    In this paper, the life cycle environmental performance of miscanthus gasification for electricity production in Denmark is evaluated and compared with that of direct combustion and anaerobic digestion. Furthermore, the results obtained are compared to those of natural gas to assess the potential...... of miscanthus as an energy source. Our results indicate that production of 1 kWh electricity from miscanthus via gasification leads to a global warming potential (100-year GWP) of 26 g and 296 g CO2e, without and with consideration of CO2 emissions from indirect land use change respectively. For other impact...

  11. Performance monitoring algorithm for optimizing electrical power generated by using photovoltaic system

    Science.gov (United States)

    Pradeep, M. V. K.; Balbir, S. M. S.; Norani, M. M.

    2016-11-01

    Demand for electricity in Malaysia has seen a substantial hike in light of the nation's rapid economic development. The current method of generating electricity is through the combustion of fossil fuels which has led to the detrimental effects on the environment besides causing social and economic outbreaks due to its highly volatile prices. Thus the need for a sustainable energy source is paramount and one that is quickly gaining acceptance is solar energy. However, due to the various environmental and geographical factors that affect the generation of solar electricity, the capability of solar electricity generating system (SEGS) is unable to compete with the high conversion efficiencies of conventional energy sources. In order to effectively monitor SEGS, this study is proposing a performance monitoring system that is capable of detecting drops in the system's performance for parallel networks through a diagnostic mechanism. The performance monitoring system consists of microcontroller connected to relevant sensors for data acquisition. The acquired data is transferred to a microcomputer for software based monitoring and analysis. In order to enhance the interception of sunlight by the SEGS, a sensor based sun tracking system is interfaced to the same controller to allow the PV to maneuver itself autonomously to an angle of maximum sunlight exposure.

  12. Microstructure and performance of multiwalled carbon nanotube/m-aramid composite films as electric heating elements.

    Science.gov (United States)

    Jeong, Young Gyu; Jeon, Gil Woo

    2013-07-24

    We report microstructure of thermomechanically stable multiwalled carbon nanotube (MWCNT)/poly(m-phenylene isophthalamide) (m-aramid) composite films containing 0.0-10.0 wt % MWCNTs and their performance as electric heating elements. FE-SEM images show that the MWCNTs are well dispersed in the composite films and are wrapped with m-aramid chains and that the interfacial thickness of m-aramid wrapped MWCNTs decreases with the MWCNT content. The electrical resistivity of films varies from ∼10(13) Ω cm for the neat m-aramid to ∼10(0) Ω cm of the film with 10.0 wt % MWCNT owing to the formation of a conductive three-dimensional network of MWCNTs. Accordingly, the performance of MWCNT/m-aramid films as electric heating elements is strongly dependent on MWCNT content as well as applied voltage. For the composite film with 10.0 wt % MWCNT, a maximum temperature of ∼176 °C is attained even at a low applied voltage of 10 V. The excellent performance such as rapid temperature response and high electric power efficiency at given applied voltages is found to be related with the microstructural features of the MWCNT/m-aramid films.

  13. Performance improvement of optical fiber coupler with electric heating versus gas heating.

    Science.gov (United States)

    Shuai, Cijun; Gao, Chengde; Nie, Yi; Peng, Shuping

    2010-08-20

    Gas heating has been widely used in the process of fused biconical tapering. However, as the instability and asymmetric flame temperature of gas heating exist, the performance of the optical devices fabricated by this method was affected. To overcome the problems resulting from gas combustion, an electric heater is designed and manufactured using a metal-ceramic (MoSi(2)) as a heating material. Our experimental data show that the fused-taper machine with an electric heater has improved the performance of optical devices by increasing the consistency of the extinction ratio, excess loss, and the splitting ratio over that of the previous gas heating mode. Microcrystallizations and microcracks were observed at the fused region of the polarization-maintaining (PM) fiber coupler and at the taper region with scanning electron microscopy and atomic force microscopy respectively. The distribution of the microcrystallizations and microcracks are nonuniform along the fiber with gas heating, while their distribution is rather uniform with electric heating. These findings show that the novel optical fiber coupler with an electric heater has improved the performance of optical fiber devices by affecting the consistency of the optical parameters and micromorphology of the surface of PM fiber.

  14. PID temperature controller in pig nursery: improvements in performance, thermal comfort, and electricity use

    Science.gov (United States)

    de Souza Granja Barros, Juliana; Rossi, Luiz Antonio; Sartor, Karina

    2016-08-01

    The use of smarter temperature control technologies in heating systems can optimize the use of electric power and performance of piglets. Two control technologies of a resistive heating system were assessed in a pig nursery: a PID (proportional, integral, and derivative) controller and a thermostat. The systems were evaluated regarding thermal environment, piglet performance, and use of electric power for 99 days. The heating system with PID controller improved the thermal environment conditions and was significantly ( P < 0.001) more efficient in terms of electricity use to produce 1 kg of body weight (2.88 kWh kg-1), specific cost (0.75 R kg-1), weight gain (7.3 kg), daily weight gain (0.21 kg day-1), and feed conversion (1.71) than the system with thermostat (3.98 kWh kg-1; 1.03 R kg-1; 5.2 kg; 0.15 kg day-1, and 2.62, respectively). The results indicate that the PID-controlled heating system is more efficient in electricity use and provides better conditions for thermal comfort and animal performance than heating with thermostat.

  15. Performance on the American Board of Family Medicine (ABFM) certification examination: are superior test-taking skills alone sufficient to pass?

    Science.gov (United States)

    O'Neill, Thomas R; Royal, Kenneth D; Puffer, James C

    2011-01-01

    Certification examinations used by American specialty boards have been the sine qua non for demonstrating the knowledge sufficient for attainment of board certification in the United States for more than 75 years. Some people contend that the examination is predominantly a test of superior test-taking skills rather than of family medicine decision-making ability. In an effort to explore the validity of this assertion, we administered the American Board of Family Medicine (ABFM) Certification to examinees who had demonstrated proficiency in taking standardized tests but had limited medical knowledge. Four nonphysician experts in the field of measurement and testing were administered one version of the 2009 ABFM certification examination. Scaled scores were calculated for each examinee, and psychometric analyses were performed on the examinees responses to examination items and compared with the performance of physicians who took the same examination. The minimum passing threshold for the examination was a scaled score of 390, corresponding to 57.7% to 61.0% of questions answered correctly, depending on the version of the examination. The 4 nonphysician examinees performed poorly, with scaled scores that ranged from 20 to 160 (mean, 87.5; SD, 57.4). The number of questions answered correctly ranged from 24.0% to 35.1% (mean, 29.2%; SD, 0.05%). Rasch analyses of the examination items revealed that the nonphysician examinees were more likely to use guessing strategies in an effort to answer questions correctly. Distracter analysis suggest near-complete randomness in the nonphysician responses. Though all 4 nonphysician examinees performed better than would have been predicted by chance alone, none performed well enough to even fall within 8 SE below the passing thresholds; their performance was far below that of almost all physicians who completed the examination. Given that the nonphysicians relied heavily on the identifying cues in the phrasing of items and the

  16. Solvothermal Synthesis of Hierarchical TiO2 Microstructures with High Crystallinity and Superior Light Scattering for High-Performance Dye-Sensitized Solar Cells.

    Science.gov (United States)

    Li, Zhao-Qian; Mo, Li-E; Chen, Wang-Chao; Shi, Xiao-Qiang; Wang, Ning; Hu, Lin-Hua; Hayat, Tasawar; Alsaedi, Ahmed; Dai, Song-Yuan

    2017-09-20

    In this article, hierarchical TiO2 microstructures (HM-TiO2) were synthesized by a simple solvothermal method adopting tetra-n-butyl titanate as the titanium source in a mixed solvent composed of N,N-dimethylformamide and acetic acid. Due to the high crystallinity and superior light-scattering ability, the resultant HM-TiO2 are advantageous as photoanodes for dye-sensitized solar cells. When assembled to the entire photovoltaic device with C101 dye as a sensitizer, the pure HM-TiO2-based solar cells showed an ultrahigh photovoltage up to 0.853 V. Finally, by employing the as-obtained HM-TiO2 as the scattering layer and optimizing the architecture of dye-sensitized solar cells, both higher photovoltage and incident photon-to-electron conversion efficiency value were harvested with respect to TiO2 nanoparticles-based dye-sensitized solar cells, resulting in a high power conversion efficiency of 9.79%. This work provides a promising strategy to develop photoanode materials with outstanding photoelectric conversion performance.

  17. Y and Ni Co-Doped BaZrO3 as a Proton-Conducting Solid Oxide Fuel Cell Electrolyte Exhibiting Superior Power Performance

    KAUST Repository

    Shafi, Shahid P.

    2015-10-16

    The fabrication of anode supported single cells based on BaZr0.8Y0.2O3-δ (BZY20) electrolyte is challenging due to its poor sinteractive nature. The acceleration of shrinkage behavior, improved sinterability and larger grain size were achieved by the partial substitution of Zr with Ni in the BZY perovskite. Phase pure Ni-doped BZY powders of nominal compositions BaZr0.8-xY0.2NixO3-δ were synthesized up to x = 0.04 using a wet chemical combustion synthesis route. BaZr0.76Y0.2Ni0.04O3-δ (BZYNi04) exhibited adequate total conductivity and the open circuit voltage (OCV) values measured on the BZYNi04 pellet suggested lack of significant electronic contribution. The improved sinterability of BZYNi04 assisted the ease in film fabrication and this coupled with the application of an anode functional layer and a suitable cathode, PrBaCo2O5+δ (PBCO), resulted in a superior fuel cell power performance. With humidified hydrogen and static air as the fuel and oxidant, respectively, a peak power density value of 428 and 240 mW cm−2 was obtained at 700 and 600°C, respectively.

  18. A comparison of Nannochloropsis salina growth performance in two outdoor pond designs: conventional raceways versus the ARID pond with superior temperature management

    Energy Technology Data Exchange (ETDEWEB)

    Crowe, Braden J.; Attalah, Said; Agrawal, Shweta; Waller, Peter; Ryan, Randy; Van Wagenen, Jonathan M.; Chavis, Aaron R.; Kyndt, John; Kacira, Murat; Ogden, Kimberly L.; Huesemann, Michael H.

    2012-10-01

    The present study examines how climatic conditions and pond design affect the growth performance of microalgae. From January to April of 2011, outdoor batch cultures of Nannochloropsis salina were grown in three replicate 780 L conventional raceways, as well as in an experimental 7500 L ARID (Algae Raceway Integrated Design) pond. The ARID culture system utilizes a series of 8 to 20 cm deep basins and a 1.5 m deep canal to enhance light exposure and mitigate temperature variations and extremes. The ARID culture reached the stationary phase 27 days earlier than the conventional raceways, which can be attributed to its superior temperature management and shallower basins. On a night when the air temperature dropped to -9 °C, the water temperature was 18 °C higher in the ARID pond than in the conventional raceways. Lipid and fatty acid content ranged from 16 - 25 % and 5 - 15 %, respectively, as a percentage of AFDW. Palmitic, palmitoleic, and eicosapentaenoic acid comprised the majority of fatty acids. While the ARID culture system achieved nearly double the volumetric productivity relative to the conventional raceways (0.023 vs 0.013 g L-1day-1), areal biomass productivities were of similar magnitude in both pond systems (3.34 vs. 3.47 g m-2day-1), suggesting that the ARID pond design has to be further optimized, most likely by increasing the culture depth or operating at higher cell densities while maintaining adequate mixing.

  19. Studying the Performance of Conductive Polymer Films as Textile Electrodes for Electrical Bioimpedance Measurements

    Science.gov (United States)

    Cunico, F. J.; Marquez, J. C.; Hilke, H.; Skrifvars, M.; Seoane, F.

    2013-04-01

    With the goal of finding novel biocompatible materials suitable to replace silver in the manufacturing of textile electrodes for medical applications of electrical bioimpedance spectroscopy, three different polymeric materials have been investigated. Films have been prepared from different polymeric materials and custom bracelets have been confectioned with them. Tetrapolar total right side electrical bioimpedance spectroscopy (EBIS) measurements have been performed with polymer and with standard gel electrodes. The performance of the polymer films was compared against the performance of the gel electrodes. The results indicated that only the polypropylene 1380 could produce EBIS measurements but remarkably tainted with high frequency artefacts. The influence of the electrode mismatch, stray capacitances and large electrode polarization impedance are unclear and they need to be clarified with further studies. If sensorized garments could be made with such biocompatible polymeric materials the burden of considering textrodes class III devices could be avoided.

  20. Electrical Performance of Electron Irradiated SiGe HBT and Si BJT

    Institute of Scientific and Technical Information of China (English)

    Wentao HUANG; Jilin WANG; Zhinong LIU; Peiyi CHEN; Peihsin TSIEN; Xiangti MENG

    2004-01-01

    The change of electrical performances of 1 MeV electron irradiated silicon-germanium (SiGe) heterojunction bipolar transistor (HBT) and Si bipolar junction transistor (BJT) was studied. After electron irradiation, both the collector current IC and the base current IB changed a little, and the current gainβ decreased a little for SiGe HBT. The higher the electron irradiation fluence was, the lower the IC decreased. For conventional Si BJT, IC and IB increased as well asβ decreased much larger than SiGe HBT under the same fluence. The contribution of IB was more important to the degradation ofβ for both SiGeHBT and Si BJT. It was shown that SiGe HBT had a larger anti-radiation threshold and better anti-radiation performance than Si BJT. The mechanism of electrical performance changes induced by irradiation was preliminarily discussed.

  1. Computer modeling of electrical and thermal performance during bipolar pulsed radiofrequency for pain relief

    Energy Technology Data Exchange (ETDEWEB)

    Pérez, Juan J. [Instituto de Investigación Interuniversitario en Bioingeniería y Tecnología Orientada al Ser Humano, Universitat Politècnica de València, Valencia 46022 (Spain); Pérez-Cajaraville, Juan J. [Pain Unit and Department of Anesthesia and Critical Care, Clínica Universidad de Navarra, University of Navarra, Pamplona 31008 (Spain); Muñoz, Víctor [Neurotherm Spain, Barcelona 08303 (Spain); Berjano, Enrique, E-mail: eberjano@eln.upv.es [Biomedical Synergy, Electronic Engineering Department, Universitat Politècnica de València 46022 (Spain)

    2014-07-15

    Purpose: Pulsed RF (PRF) is a nonablative technique for treating neuropathic pain. Bipolar PRF application is currently aimed at creating a “strip lesion” to connect the electrode tips; however, the electrical and thermal performance during bipolar PRF is currently unknown. The objective of this paper was to study the temperature and electric field distributions during bipolar PRF. Methods: The authors developed computer models to study temperature and electric field distributions during bipolar PRF and to assess the possible ablative thermal effect caused by the accumulated temperature spikes, along with any possible electroporation effects caused by the electrical field. The authors also modeled the bipolar ablative mode, known as bipolar Continuous Radiofrequency (CRF), in order to compare both techniques. Results: There were important differences between CRF and PRF in terms of electrical and thermal performance. In bipolar CRF: (1) the initial temperature of the tissue impacts on temperature progress and hence on the thermal lesion dimension; and (2) at 37 °C, 6-min of bipolar CRF creates a strip thermal lesion between the electrodes when these are separated by a distance of up to 20 mm. In bipolar PRF: (1) an interelectrode distance shorter than 5 mm produces thermal damage (i.e., ablative effect) in the intervening tissue after 6 min of bipolar RF; and (2) the possible electroporation effect (electric fields higher than 150 kV m{sup −1}) would be exclusively circumscribed to a very small zone of tissue around the electrode tip. Conclusions: The results suggest that (1) the clinical parameters considered to be suitable for bipolar CRF should not necessarily be considered valid for bipolar PRF, and vice versa; and (2) the ablative effect of the CRF mode is mainly due to its much greater level of delivered energy than is the case in PRF, and therefore at same applied energy levels, CRF, and PRF are expected to result in same outcomes in terms of

  2. Environmental Performance of Electricity Generation Based on Resources: A Life Cycle Assessment Case Study in Turkey

    Directory of Open Access Journals (Sweden)

    Zerrin Günkaya

    2016-10-01

    Full Text Available The aim of this paper was to determine how to change the environmental performance of electricity generation depending on the resources and their shares, in order to support decision-makers. Additionally, this paper presents an application of life cycle assessment (LCA methodology to determine the environmental burdens of electricity generation in Turkey. Electricity generation data in Turkey for the years 2012 and 2023 were used as a case study. The functional unit for electricity generation was 1 kWh. The LCA calculations were carried out using CML-IA (v3.00 data and the results were interpreted with respect to Monte Carlo simulation analysis (with the Monte Carlo function built in SimaPro 8.0.1 software. The results demonstrated that the fossil fuel consumption not only contributes to global warming, but it also has effects on the elemental basis of abiotic depletion due to raw material consumption for plant infrastructure. Additionally, it was observed that the increasing proportion of wind power in the electricity mix would also increase certain life cycle impacts (such as the elemental basis of abiotic depletion, human ecotoxicity, and terrestrial ecotoxicity in Turkey’s geography compared to increasing the share of other renewable energy sources, such as hydropower, geothermal, as well as solar.

  3. Core–shell structure carbon coated ferric oxide (Fe{sub 2}O{sub 3}@C) nanoparticles for supercapacitors with superior electrochemical performance

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Yipeng [School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006 (China); Zhang, Haiyan [School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006 (China); Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter, Guangzhou 510006 (China); Chen, Yiming, E-mail: chenym@gdut.edu.cn [School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006 (China); Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter, Guangzhou 510006 (China); Deng, Peng; Huang, Zhikun [School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006 (China); Liu, Liying; Qian, Yannan; Li, Yunyong [School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006 (China); Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter, Guangzhou 510006 (China); Li, Qingyu [School of Chemistry and Chemistry Engineering, Guangxi Normal University, Guilin 541004 (China)

    2015-08-05

    Highlights: • Fe{sub 2}O{sub 3}@C was prepared by using arc discharge method followed by heat treatment. • KOH activation made the core–shell structure Fe{sub 2}O{sub 3}@C porous. • The activated-Fe{sub 2}O{sub 3}@C supercapacitor exhibited superior electrochemical performance. - Abstract: Core–shell structure carbon coated ferric oxide nanoparticles (Fe{sub 2}O{sub 3}@C) were fabricated by the oxidation of carbon coated iron nanoparticles (Fe@C) prepared by a direct current carbon arc discharge method. Porous activated-Fe{sub 2}O{sub 3}@C was prepared by KOH activation of Fe{sub 2}O{sub 3}@C at the temperature of 750 °C. X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to characterize the structure and morphology of the Fe{sub 2}O{sub 3}@C and activated-Fe{sub 2}O{sub 3}@C. The specific surface area and pore size distribution of the samples were also tested. The activated-Fe{sub 2}O{sub 3}@C electrodes exhibited good electrochemical performance with a maximum specific capacitance of 612 F g{sup −1} at the charge/discharge current density of 0.5 A g{sup −1} with 5 M NaOH electrolyte. After 10,000 cycling DC tests at the charge/discharge current density of 4 A g{sup −1}, a high level specific capacitance of 518 F g{sup −1} was obtained (90.6% retention of the initial capacity), suggesting excellent long-term cycling stability.

  4. Effects of hot pressing on electric performances of Bi0.5Sb1.5Te3

    Institute of Scientific and Technical Information of China (English)

    XIAO Bo; CHEN Hui; WU Borong; ZHU Lei; LIU Mingyi; JIAN Xuyu; LI Lin

    2006-01-01

    The effects of hot pressing on electric performance and mechanical strength of Bi0.5Sb1.5Te3 thermoelectric material prepared through vacuum melting and milling were studied. The phase constituent and microstructure were analyzed by X-ray Diffraction and cold field emission Scanning Electric Microscope. Aeolotropisms of the material on microstructure and electric performances are approved. With the rise of hot pressing temperature (from 300-500 ℃) and pressure (30-70 Mpa), electric conductivity and power factor are improved. Moreover, Bi0.5Sb1.5Te3 material can gain ideal thermoelectric performances and increased mechanical strength by hot pressing.

  5. Electrical performance of InAs/AlSb/GaSb superlattice photodetectors

    Science.gov (United States)

    Tansel, T.; Hostut, M.; Elagoz, S.; Kilic, A.; Ergun, Y.; Aydinli, A.

    2016-03-01

    Temperature dependence of dark current measurements is an efficient way to verify the quality of an infrared detector. Low dark current density values are needed for high performance detector applications. Identification of dominant current mechanisms in each operating temperature can be used to extract minority carrier lifetimes which are highly important for understanding carrier transport and improving the detector performance. InAs/AlSb/GaSb based T2SL N-structures with AlSb unipolar barriers are designed for low dark current with high resistance and detectivity. Here we present electrical and optical performance of such N-structure photodetectors.

  6. Energy, Environmental and Economic Performance of a Micro-trigeneration System upon Varying the Electric Vehicle Charging Profiles

    Directory of Open Access Journals (Sweden)

    Sergio Sibilio

    2017-09-01

    Full Text Available The widespread adoption of electric vehicles and electric heat pumps would result in radically different household electrical demand characteristics, while also possibly posing a threat to the stability of the electrical grid. In this paper, a micro-trigeneration system (composed of a 6.0 kWel cogeneration device feeding a 4.5 kWcool electric air-cooled vapor compression water chiller serving an Italian residential multi-family house was investigated by using the dynamic simulation software TRNSYS. The charging of an electric vehicle was considered by analyzing a set of seven electric vehicle charging profiles representing different scenarios. The simulations were performed in order to evaluate the capability of micro-cogeneration technology in: alleviating the impact on the electric infrastructure (a; saving primary energy (b; reducing the carbon dioxide equivalent emissions (c and determining the operating costs in comparison to a conventional supply system based on separate energy production (d.

  7. INFLUENCE OF LINING THERMAL PERFORMANCE IN ELECTRIC-ARC FURNACES ON POWER CONSUMPTION

    Directory of Open Access Journals (Sweden)

    S.. V. Korneev

    2014-01-01

    Full Text Available The paper presents an analysis of specific features of lining thermal performance in electric-arc furnaces at various technological periods. It has been  shown that on the basis of mathematical modeling methods for thermal processes it is possible to predict power consumption of furnaces at the operational split schedule with due account of such furnace characteristics as capacity, lining materials, furnace idle times under closed and open conditions etc. The paper shows distinctions in thermal performance of acid and the basic linings in the electric-arc furnaces. The proposed approach allows to analyze thermal losses by heat conductivity and on accumulation by a refractory lining and rather accurately to determine the required balance sheet items while calculating power consumption during various periods of scrap melting for furnaces of various capacity.

  8. Environmental performance of crop residues as an energy source for electricity production

    DEFF Research Database (Denmark)

    Nguyen, T Lan T; Hermansen, John Erik; Mogensen, Lisbeth

    2013-01-01

    or for natural gas reduces global warming, non-renewable energy use, human toxicity and ecotoxicity, but increases eutrophication, respiratory inorganics, acidification and photochemical ozone. The results at the aggregate level show that the use of straw biomass for conversion to energy scores better than...... that of coal but worse than natural gas. In order to investigate the question of whether and how a reduction in the single score per kW h of electricity produced from straw is feasible, we perform a scenario analysis where we consider two approaches. The first one is a potential significant reduction......This paper aims to address the question, “What is the environmental performance of crop residues as an alternative energy source to fossil fuels, and whether and how can it be improved?”. In order to address the issue, we compare electricity production from wheat straw to that from coal and natural...

  9. A highly efficient electric additive for enhancing photovoltaic performance of dye-sensitized solar cells

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    N-cetylpyridinium iodide (N-CPI) as a new electric additive for enhancing photovoltaic performance of the dye-sensitized solar cell (DSSC) was studied.It showed high efficiency for enhancing both the open-circuit voltage and the short-circuit current density of DSSC when the suitable amount of N-CPI as 0.02 M was added in liquid electrolyte.The energy conversion effi- ciency of DSSC increased from 4.429% to 6.535%,with 47.55% enhancement.Therefore,it is a highly efficient electric addi- tive for DSSC.The intrinsic reason is owing to the special molecular structure of N-CPI,which contains two different polarity groups.As a surfactant,N-CPI could form ordered arrangement in liquid electrolyte,which affects the diffusing ability and the redox reaction of I-/I3-,and further affects the photovoltaic performance of DSSC.

  10. The effect of temperature changes on electrical performance of the betavoltaic cell

    Energy Technology Data Exchange (ETDEWEB)

    Wang Guanquan, E-mail: Wang.gq@163.co [Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, Sichuan 621900 (China); Hu Rui; Wei Hongyuan; Zhang Huaming; Yang Yuqing; Xiong Xiaoling; Liu Guoping; Luo Shunzhong [Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, Sichuan 621900 (China)

    2010-12-15

    There is a significant relationship between temperature and electrical performance of a betavoltaic cell. Two silicon diodes used as energy conversion devices of betavoltaic cells were irradiated by Ni-63, and the relationships between the temperature and the electrical performance such as V{sub oc}, I{sub sc}, and P{sub max} were examined. I{sub sc} increased very little as temperature increased but V{sub oc} decreased considerably. The changing values of V{sub oc} were -3.1 and -3.0 mV/K, respectively, in the temperature range 233.15-333.15 K. As a result of this, P{sub max} and {eta} also decreased markedly.

  11. Impact of Physical Deformation on Electrical Performance of Paper-Based Sensors

    KAUST Repository

    Nassar, Joanna M.

    2017-01-23

    We report on investigation of the mechanical properties of paper electronics (printed and made out of paper). One key objective of such paper electronics is to achieve ultraflexibility. Therefore, it is important to understand electrical functionality and reliability of paper electronics under various physical (mechanical) deformations. Here, we show the general mechanical properties of the cellulose paper used and its electrical behavior under applied strain, tackling the main effects that need to be identified when building paper-based systems, from product performance and stability perspective. An overview of the stress-strain behavior of silver ink on paper is discussed, and then, we tackle a more specific analysis of the performance variations of paper sensors made with recyclable household materials when exposed to various mechanical conditions of tensile and compressive bending. This paper is important for developing stable wearable sensors for incorporation into Internet of Everything applications.

  12. Performance Characteristics of a Modularized and Integrated PTC Heating System for an Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Yoon Hyuk Shin

    2015-12-01

    Full Text Available A modularized positive temperature coefficient heating system has controller-integrated heater modules. Such a heating system that uses a high-voltage power of 330 V was developed in the present study for use in electric vehicles. Four heater modules and one controller with an input power of 5.6 kW were integrated in the modularized system, which was designed for improved heating power density and light weight compared to the conventional heating system, in which the controller is separated. We experimentally investigated the performance characteristics, namely, the heating capacity, energy efficiency, and pressure drop, of a prototype of the developed heating system and found it to have satisfactory performance. The findings of this study will contribute to the development of heating systems for electric vehicles.

  13. Investigations on the performances of the electrical generator of a rim-driven marine current turbine”

    OpenAIRE

    2008-01-01

    In this paper, the electrical generator of a rim-driven horizontal-axis current turbine is modeled in detail. Its main characteristics and performances are evaluated (efficiency, mass, cost, etc). This generator is of permanent magnet direct-driven synchronous type and is connected to a variable speed power electronics drive. It is then compared to a more traditional technology (a pod generator) in terms of mass and cost for a common set of specification. In addition, due to the specific geom...

  14. Electrical resistivity testing for as-built concrete performance assessment of chloride penetration resistance

    OpenAIRE

    Polder, R.B.; Peelen, W.H.A.

    2014-01-01

    The electrical resistivity of concrete can provide information about its transport properties, which is relevant for durability performance. For example, resistivity is inversely proportional to chloride diffusion, at least within similar concrete compositions. A methodology is proposed for on-site assessment of concrete cover resistance against chloride penetration, based on on-site resistivity testing. As such, resistivity testing can extend existing service life approaches to assessing on ...

  15. Thermal Design and Performance of the Electrical Distribution Feed Box of the LHC prototype cell

    CERN Document Server

    Calzas-Rodriguez, C; Hauviller, Claude; Poncet, Alain; Sacré, P; Serio, L

    2002-01-01

    The Electrical Distribution Feed Box (DFBS) is a 4.5 K saturated liquid helium cryostat constructed for the Large Hadron Collider (LHC) Prototype Cell (String 2). The thermal design of the DFBS is presented, with emphasis on the modelling of the cooling of the current lead chimneys via the helium bath boil-off gas and on the design of the lambda plate. The expected performance is compared to measurements done during the first operation phase of the LHC prototype cell.

  16. Performance of a 10 kilowatt wind-electric water pumping system for irrigating crops

    Energy Technology Data Exchange (ETDEWEB)

    Vick, B.D.; Clark, R.N. [Conservation and Production Research Lab., Bushland, TX (United States); Molla, S. [Texas A& M Univ., College Station, TX (United States)

    1997-12-31

    A 10 kW wind-electric water pumping system was tested for field crop irrigation at pumping depths from 50 to 120 m. The wind turbine for this system used a permanent magnet alternator that powered off-the-shelf submersible motors and pumps without the use of an inverter. Pumping performance was determined at the USDA-Agricultural Research Service (ARS), Wind Energy Laboratory in Bushland, TX for the 10 kW wind turbine using a pressure valve and a pressure tank to simulate different pumping depths. Pumping performance was measured for two 10 kW wind turbines of the same type at farms near the cities of Garden City, TX and Stiles, TX. The pumping performance data collected at these actual wells compared favorably with the data collected at the USDA-ARS, Wind Energy Laboratory. If utility generated electricity was accessible, payback on the wind turbine depended on the cost of utility generated electricity and the transmission line extension cost.

  17. Well-Combined Magnetically Separable Hybrid Cobalt Ferrite/Nitrogen-Doped Graphene as Efficient Catalyst with Superior Performance for Oxygen Reduction Reaction.

    Science.gov (United States)

    Lu, Lei; Hao, Qingli; Lei, Wu; Xia, Xifeng; Liu, Peng; Sun, Dongping; Wang, Xin; Yang, Xujie

    2015-11-18

    Catalysts with low-cost, high activity and stability toward oxygen reduction reaction (ORR) are extremely desirable, but its development still remains a great challenge. Here, a novel magnetically separable hybrid of multimetal oxide, cobalt ferrite (CoFe2O4), anchored on nitrogen-doped reduced graphene oxide (CoFe2O4/NG) is prepared via a facile solvothermal method followed by calcination at 500 °C. The structure of CoFe2O4/NG and the interaction of both components are analyzed by several techniques. The possible formation of Co/Fe-N interaction in the CoFe2O4/NG catalyst is found. As a result, the well-combination of CoFe2O4 nanoparticles with NG and its improved crystallinity lead to a synergistic and efficient catalyst with high performance to ORR through a four-electron-transfer process in alkaline medium. The CoFe2O4/NG exhibits particularly comparable catalytic activity as commercial Pt/C catalyst, and superior stability against methanol oxidation and CO poisoning. Meanwhile, it has been proved that both nitrogen doping and the spinel structure of CoFe2O4 can have a significant contribution to the catalytic activity by contrast experiments. Multimetal oxide hybrid demonstrates better catalysis to ORR than a single metal oxide hybrid. All results make the low-cost and magnetically separable CoFe2O4/NG a promising alternative for costly platinum-based ORR catalyst in fuel cells and metal-air batteries. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Uniformly active phase loaded selective catalytic reduction catalysts (V{sub 2}O{sub 5}/TNTs) with superior alkaline resistance performance

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Haiqiang; Wang, Penglu [Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental & Resources Science, Zhejiang University, 310058 Hangzhou (China); Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control, Hangzhou 310027 (China); Chen, Xiongbo [South China Institute of Environmental Sciences, Ministry of Environmental Protection, Guangzhou 510655 (China); Wu, Zhongbiao, E-mail: zbwu@zju.edu.cn [Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental & Resources Science, Zhejiang University, 310058 Hangzhou (China); Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control, Hangzhou 310027 (China)

    2017-02-15

    Highlights: • VOSO{sub 4} exhibited better synergistic effect with titanate nanotubes than NH{sub 4}VO{sub 3}. • Ion-exchange reaction occurs between VOSO{sub 4} and titanate nanotubes. • Ion-exchange resulting in uniformly vanadium distribution on titanate nanotubes. • VOSO{sub 4}-based catalyst exhibited impressive SCR activity and alkaline resistance. - Abstract: In this work, protonated titanate nanotubes was performed as a potential useful support and different vanadium precursors (NH{sub 4}VO{sub 3} and VOSO{sub 4}) were used to synthesize deNO{sub x} catalysts. The results showed that VOSO{sub 4} exhibited better synergistic effect with titanate nanotubes than NH{sub 4}VO{sub 3}, which was caused by the ion-exchange reaction. Then high loading content of vanadium, uniformly active phase distribution, better dispersion of vanadium, more acid sites, better V{sup 5+}/V{sup 4+} redox cycles and superior oxygen mobility were achieved. Besides, VOSO{sub 4}-based titanate nanotubes catalysts also showed enhanced alkaline resistance than particles (P25) based catalysts. It was strongly associated with its abundant acid sites, large surface area, flexible redox cycles and oxygen transfer ability. For the loading on protonated titanate nanotubes, active metal with cation groups was better precursors than anion ones. V{sub 2}O{sub 5}/TNTs catalyst was a promising substitute for the commercial vanadium catalysts and the work conducted herein provided a useful idea to design uniformly active phase loaded catalyst.

  19. A Novel Magnetically Recoverable Ni-CeO2-x/Pd Nanocatalyst with Superior Catalytic Performance for Hydrogenation of Styrene and 4-Nitrophenol.

    Science.gov (United States)

    Jiang, Yi-Fan; Yuan, Cheng-Zong; Xie, Xiao; Zhou, Xiao; Jiang, Nan; Wang, Xin; Imran, Muhammad; Xu, An-Wu

    2017-02-28

    Metal/support nanocatalysts consisting of various metals and metal oxides not only retain the basic properties of each component, but also exhibit higher catalytic activity due to their synergistic effects. Herein, we report the creation of a highly efficient, long-lasting and magnetic recyclable catalyst, composed of magnetic nickel (Ni) nanoparticles (NPs), active Pd NPs and oxygen deficient CeO2-x support. These hybrid nanostructures composed of oxygen deficient CeO2-x and active metal nanoparticles could effectively facilitate diffusion of reactant molecules and active site exposure that can dramatically accelerate the reaction rate. Impressively, the rate constant k and k/m of 4-nitrophenol reduction over 61 wt%Ni-CeO2-x/0.1 wt%Pd catalyst are respectively 0.0479 s-1 and 2.1×104 min-1 g-1, and the reaction conversion shows negligible decline even after 20 cycles. Meanwhile, the optimal 61 wt%Ni-CeO2-x/3 wt%Pd catalyst manifests remarkable catalytic activity towards styrene hydrogenation with a high TOF of 6827 molstyrene molPd-1 h-1 and a selective conversion of 100% to ethylbenzene even after eight cycles. The strong metal-support interaction (SMSI) between Ni NPs, Pd NPs and oxygen deficient CeO2-x support is beneficial for superior catalytic efficiency and stability toward hydrogenation of styrene and 4-nitrophenol. Moreover, Ni species could boost the catalytic activity of Pd due to their synergistic effect and strengthen the interaction between reactant and catalyst, which seems responsible for the great enhancement of catalytic activity. Our findings provide a new perspective to develop other high-performance and magnetically recoverable nanocatalysts, which would be widely applied to a variety of catalytic reactions.

  20. A Comparison of Nannochloropsis salina Growth Performance in Two Outdoor Pond Designs: Conventional Raceways versus the ARID Pond with Superior Temperature Management

    Directory of Open Access Journals (Sweden)

    Braden Crowe

    2012-01-01

    Full Text Available The present study examines how climatic conditions and pond design affect the growth performance of microalgae. From January to April of 2011, outdoor batch cultures of Nannochloropsis salina were grown in three replicate 780 L conventional raceways, as well as in an experimental 7500 L algae raceway integrated design (ARID pond. The ARID culture system utilizes a series of 8–20 cm deep basins and a 1.5 m deep canal to enhance light exposure and mitigate temperature variations and extremes. The ARID culture reached the stationary phase 27 days earlier than the conventional raceways, which can be attributed to its superior temperature management and shallower basins. On a night when the air temperature dropped to −9°C, the water temperature was 18°C higher in the ARID pond than in the conventional raceways. Lipid and fatty acid content ranged from 16 to 25% and from 5 to15%, respectively, as a percentage of AFDW. Palmitic, palmitoleic, and eicosapentaenoic acids comprised the majority of fatty acids. While the ARID culture system achieved nearly double the volumetric productivity relative to the conventional raceways (0.023 versus 0.013 g L−1day−1, areal biomass productivities were of similar magnitude in both pond systems (3.47 versus 3.34 g m−2day−1, suggesting that the ARID pond design has to be further optimized, most likely by increasing the culture depth or operating at higher cell densities while maintaining adequate mixing.

  1. Announcement of Superior Council of Electricity and Gas about the future gas system; Avis du Conseil Superieur de l'Electricite et du Gaz sur le futur systeme gazier

    Energy Technology Data Exchange (ETDEWEB)

    Superior Council of Electricity and Gas [ed.] [Ministere de l' Economie, des Finances et de l' Industrie, Paris (France)

    1999-12-02

    This document is an announcement of the Superior Council of Electricity and Gas (CSEG) concerning the future gas system of France. It was asked by the Secretary of State for industry having in view the preparation of the law of organization of gas sector. Without refraining to reveal the internal divergences, the CSEG intended to provide a framework of exchanges on the definition of Public Service in the field of natural gas, on regulation, on juridical regime of the gas transport and various relating subjects, as well as on the social questions. Also, the CSEG aimed at emphasizing a number of predominant points of view. It is stressed that the future law concerning the gas system should take into consideration the peculiarities of the activity in the gas sector, since the mere transposition into the gas sector of the measures valid in the electricity sector could is inadequate. The CSEG underlines its firm attachment to the notion of Public Service and the principle of subsidiarity. It also signals out the necessity of taking into account the industrial problems, i.e., placing the French gas operators into a more open position, turning synergically to good account the EDF, developing gas partnerships downstream and upstream and using vigorously its advantages. These issues should be also taken into account in case of industrial gas customers to ensure their competing European position. Price lowering as well as increasing the quality of services should be pursued actively. The document contains the following sections: I. The Public Service; II. The regulation; III. The juridical regime of transport, the distribution and the storage; IV. The social question.

  2. AN EXPLORATORY ANALYSIS ON HALF-HOURLY ELECTRICITY LOAD PATTERNS LEADING TO HIGHER PERFORMANCES IN NEU

    Directory of Open Access Journals (Sweden)

    K.A.D. Deshani

    2014-05-01

    Full Text Available Accurate prediction of electricity demand can bring extensive benefits to any country as the forecasted values help the relevant authorities to take decisions regarding electricity generation, transmission and distribution appropriately. The literature reveals that, when compared to conventional time series techniques, the improved artificial intelligent approaches provide better prediction accuracies. However, the accuracy of predictions using intelligent approaches like neural networks are strongly influenced by the correct selection of inputs and the number of neuro-forecasters used for prediction. Deshani, Hansen, Attygalle, & Karunarathne (2014 suggested that a cluster analysis could be performed to group similar day types, which contribute towards selecting a better set of neuro-forecasters in neural networks. The cluster analysis was based on the daily total electricity demands as their target was to predict the daily total demands using neural networks. However, predicting half-hourly demand seems more appropriate due to the considerable changes of electricity demand observed during a particular day. As such clusters are identified considering half-hourly data within the daily load distribution curves. Thus, this paper is an improvement to Deshani et. al. (2014, which illustrates how the half hourly demand distribution within a day, is incorporated when selecting the inputs for the neuro-forecasters.

  3. Simulating Study on Drive System Performance for Hybrid Electric Bus Based on ADVISOR

    Directory of Open Access Journals (Sweden)

    Wang Xingxing

    2017-01-01

    Full Text Available Hybrid electric bus has a number of advantages when compared with ordinary passenger cars, but in the dynamic matching and the vehicle performance are difficult to detect, thus limits its development process. In this paper, combined with the actual models, the hybrid electric bus module parameters were modified in the software of ADVISOR (Advanced Vehicle Simulator, main including: module of the vehicle, the wheel module, motor module, a battery module and engine module, three kinds of bus models for A, B and C were established, and the related performance that need to be analyzed was set up, such as acceleration, gradability, emissions and energy utilization and so on, in order to ensure the vehicle running in the same environment and convenient for comparison, a fixed vehicle driving cycles was chose, then the simulation results was analyzed, and the various performance was compared with the dynamic indicators and economic indicators which determined by referencing of traditional city bus standard and each other, and finally, the performance optimal model of B was chose out which can meet the demand, its related performance parameters of the simulation results are as follows: the best gradability is 26%, maximum speed is 72.7km/h, maximum acceleration is 1.7m/s2, 0~50km/h acceleration time is 9.5s and fuel consumption is 25L/km.

  4. Performance of Klebsiella oxytoca to generate electricity from POME in microbial fuel cell

    Directory of Open Access Journals (Sweden)

    Islam Md. Amirul

    2016-01-01

    Full Text Available This study is aimed to evaluate the electricity generation from microbial fuel cell (MFC and to analyze the microbial community structure of city wastewater and anaerobic sludge to enhance the MFC performance. MFCs, enriched with palm oil mill effluent (POME were employed to harvest electricity by innoculating of Klebsiella oxytoca, collected from city wastewater and other microbes from anaerobic sludge (AS. The MFC showed maximum power density of 207.28 mW/m3 with continuous feeding of POME using microbes from AS. Subsequent replacement with Klebsiella oxytoca resulted maximum power density of 1236 mW/m3 by utilizing complex substrate POME which was six times higher as compared to MFC operated with AS. Based on Biolog gene III analysis, relatively higher abundance of Klebsiella oxytoca was detected in the city wastewater. Predominant microorganisms such as Gammaproteobacteria, Azospiraoryzae, Acetobacterperoxydans and Solimonasvariicoloris were isolated from palm oil anaerobic sludge as well as from biofilm of MFC. Enriched electrochemically active bacteria Klebsiella oxytoca showed better performance to generate electricity from complex POME substrates compare to AS. These results demonstrate that the power output of MFCs can be increased significantly using Klebsiella oxytoca.

  5. Auditory maturity and hearing performance in inner ear malformations: a histological and electrical stimulation approach.

    Science.gov (United States)

    Sainz, Manuel; Garcia-Valdecasas, Juan; Fernandez, Elena; Pascual, Maria Teresa; Roda, Olga

    2012-06-01

    The objective of this study was to assess the auditory performance of the neural structures in response to controlled electrical stimulation period. A prospective cohort study focused on the intracochlear electrical stimulation parameters and hearing performance of patients suffering different cochlear malformations who were treated by cochlear implants constituted the study design. The study sample constituted 16 patients, suffering profound prelingual hearing impairment, diagnosed on the basis of radiological criteria as having an inner ear malformation, and who underwent cochlear implantation and were followed for 24 months. Patients with common cavities, characterized by fewer nerve structures involved, less epithelial penetration, and deficient cochlear tonotopy distribution showed have higher thresholds and electrical charges than patients with cochlear hypoplasia, who in turn have higher thresholds than patients with minor malformations (p malformation and was also poor in patients with cochlear hypoplasia, who were unable to discriminate more than 50% of the words and relied on visual cues as a necessary aid to communication. Better results were reached by minor malformed inner ears. To conclude, the number of nerve structures involved, epithelial penetration and deficient cochlear tonotopy are responsible of inner ear functionality.

  6. Electrical performance and chemical composition studies on original and falsified Ni-MH batteries

    Directory of Open Access Journals (Sweden)

    Alexandre Urbano

    2010-12-01

    Full Text Available We show in this paper that falsifications on technological products have hit even rechargeable nickel metal hydride batteries (Ni-MH. The electrical performance and the electrode chemical composition were investigated for authentic and falsified AAA Ni-MH batteries, purchased in the Londrina market, Paraná State. Battery charge capacities were measured at 0,2 C discharge rate and average electrical power was measured at 0.2 and 0.8 C discharge rate. To perform chemical composition analysis, the batteries were vacuum dismantled and their electrodes were characterized by Energy Dispersive X-Ray Fluorescence (EDXRF and X-Ray Diffraction (XRD techniques. It was observed that the charge capacities for the authentic and falsified batteries were 920 and 154 mAh, respectively. The average electrical powers were 210 mW for authentic and 41 mW for falsified batteries. The cathode chemical composition was nickel hydroxide, (Ni(OH2, for both kinds of batteries. However, the anodes of these batteries were not composed by the same materials. The alloy LaNi5 was identified as the electroactive compound in the anode of the authentic battery, while cadmium hydroxide compound, (Cd (OH2, was identified in the falsified battery anode. The authentic battery therefore presented six times more charge capacity, five times more power at 0.2 C discharge rate and 6 times at 0.8 C than the falsified battery, and are yet less dangerous to environment due cadmium absence.

  7. Skid resistance performance of asphalt wearing courses with electric arc furnace slag aggregates.

    Science.gov (United States)

    Kehagia, Fotini

    2009-05-01

    Metallurgical slags are by-products of the iron and steel industry and are subdivided into blast furnace slag and steel slag according to the different steel-producing processes. In Greece, slags are mostly produced from steelmaking using the electric arc furnace process, and subsequently are either disposed in a random way or utilized by the cement industry. Steel slag has been recently used, worldwide, as hard aggregates in wearing courses in order to improve the skidding resistance of asphalt pavements. At the Highway Laboratory, Department of Civil Engineering of Aristotle University of Thessaloniki research has been carried out in the field of steel slags, and especially in electric arc furnace (EAF) slag, to evaluate their possible use in highway engineering. In this paper, the recent results of anti-skidding performance of steel slag aggregates in highway pavements are presented.

  8. High-performance liquid-catalyst fuel cell for direct biomass-into-electricity conversion.

    Science.gov (United States)

    Liu, Wei; Mu, Wei; Deng, Yulin

    2014-12-01

    Herein, we report high-performance fuel cells that are catalyzed solely by polyoxometalate (POM) solution without any solid metal or metal oxide. The novel design of the liquid-catalyst fuel cells (LCFC) changes the traditional gas-solid-surface heterogeneous reactions to liquid-catalysis reactions. With this design, raw biomasses, such as cellulose, starch, and even grass or wood powders can be directly converted into electricity. The power densities of the fuel cell with switchgrass (dry powder) and bush allamanda (freshly collected) are 44 mW cm(-2) and 51 mW cm(-2) respectively. For the cellulose-based biomass fuel cell, the power density is almost 3000 times higher than that of cellulose-based microbial fuel cells. Unlike noble-metal catalysts, POMs are tolerant to most organic and inorganic contaminants. Therefore, almost any raw biomass can be used directly to produce electricity without prior purification.

  9. Isolated superior mesenteric artery dissection

    Directory of Open Access Journals (Sweden)

    Lalitha Palle

    2010-01-01

    Full Text Available Isolated superior mesenteric artery (SMA dissection without involvement of the aorta and the SMA origin is unusual. We present a case of an elderly gentleman who had chronic abdominal pain, worse after meals. CT angiography, performed on a 64-slice CT scanner, revealed SMA dissection with a thrombus. A large artery of Drummond was also seen. The patient was managed conservatively.

  10. An integrated tool and improved performance metrics to monitor the adequacy of the North American electric power system

    Science.gov (United States)

    Bilke, Terry

    The reliability of the electric power system, defined as the degree of performance of the grid according to accepted standards, is composed of two components: (1) Security: The ability of the electric system to withstand sudden disturbances such as electric short circuits or unanticipated loss of system elements. (2) Adequacy: The ability of the electric system to supply the aggregate electrical demand and energy requirements of the customers at all times, taking into account scheduled and reasonably expected unscheduled outages of system elements. There is evidence that the performance of the adequacy component of reliability is declining in North America. This research presents an improved set of metrics and a tool that supports an adequacy-monitoring model designed to track performance and identify underlying problems that impact reliability.

  11. Electrical performance of distribution insulators with chlorella vulgaris growth on its surface

    Directory of Open Access Journals (Sweden)

    H. E. Rojas

    2015-11-01

    Full Text Available This paper presents a study about electrical performance of ceramic and polymeric insulators bio-contaminated with alga Chlorella vulgaris. The performed tests involve ANSI 55-2 and ANSI 52-1 ceramic insulators and ANSI DS-15 polymeric insulators, all of them used in distribution systems of Colombia. Biological contamination of insulators is realized using a controlled environment chamber that adjusts the temperature, humidity and light radiation. The laboratory tests include measurements of flashover voltages and leakage currents and they were performed to determine how insulators are affected by biological contamination. After a series of laboratory tests, it was concluded that the presence of Chlorella vulgaris on the contaminated ceramic insulators reduces the wet flashover voltage up to 12% and increases their leakage currents up to 80%. On the other hand, for polymeric insulators the effect of algae growth on flashover voltages was not to strong, although the leakage currents increase up to 60%.

  12. Electrical performance of a string of magnets representing a half-cell of the LHC machine

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Mateos, F.; Coull, L.; Dahlerup-Petersen, K.; Hagedorn, D.; Krainz, G.; Rijllart, A. [European Organization for Nuclear Research, Geneva (Switzerland); McInturff, A. [Lawrence Berkeley Lab., CA (United States)

    1995-06-21

    Tests have been carried out on a string prototype superconducting magnets, consisting of one double-quadrupole and two double-dipoles forming the major part of a half-cell of the LHC machine. The magnets are protected individually by ``cold diodes`` and quench heaters. The electrical aspects of these tests are described here. The performance during quench of the protection diodes and the associated interconnections was studied. Tests determined the magnet quench performance in training and at different ramp-rates, and investigated the inter-magnet propagation of quenches. Current lead and inter-magnet contact resistances were controlled and the performance of the power converter and the dump switches assessed.

  13. Algorithm to determine electrical submersible pump performance considering temperature changes for viscous crude oils

    Energy Technology Data Exchange (ETDEWEB)

    Valderrama, A. [Petroleos de Venezuela, S.A., Distrito Socialista Tecnologico (Venezuela); Valencia, F. [Petroleos de Venezuela, S.A., Instituto de Tecnologia Venezolana para el Petroleo (Venezuela)

    2011-07-01

    In the heavy oil industry, electrical submersible pumps (ESPs) are used to transfer energy to fluids through stages made up of one impeller and one diffuser. Since liquid temperature increases through the different stages, viscosity might change between the inlet and outlet of the pump, thus affecting performance. The aim of this research was to create an algorithm to determine ESPs' performance curves considering temperature changes through the stages. A computational algorithm was developed and then compared with data collected in a laboratory with a CG2900 ESP. Results confirmed that when the fluid's viscosity is affected by the temperature changes, the stages of multistage pump systems do not have the same performance. Thus the developed algorithm could help production engineers to take viscosity changes into account and optimize the ESP design. This study developed an algorithm to take into account the fluid viscosity changes through pump stages.

  14. Performance Evaluation of Sub-manufacturing Sectors Using TOPSIS and ELECTRE Methods

    Directory of Open Access Journals (Sweden)

    Nuri ÖMÜRBEK

    2014-06-01

    Full Text Available Performance analysis is defined as a process of collecting, analyzing and reporting data systematically and regularly for a business to monitor its sources it has used, products and services it has produced, and the results it gained. For operators, it means quantitative expression of actions which are performed by a business or maintained in a program. In this study, financial performances of manufacture sectors are analyzed by the methods of TOPSIS and ELECTRE using current ratio, cash ratio, total debt / total assets, inventory turnover rate, equity turnover rate, net profit / equity, operating ıncome /net sales, net profit / sales and cost of good sold / net sales criteria. The findings suggest that coal and refined petroleum product manufacturing industry is in the first place in both methods.

  15. A Review of Research on Improvement and Optimization of Performance Measures for Electrical Discharge Machining

    Directory of Open Access Journals (Sweden)

    C. R. Sanghani

    2014-01-01

    Full Text Available Electrical Discharge Machining (EDM is a non conventional machining method which can be used to machine electrically conductive work pieces irrespective of their shape, hardness and toughness. High cost of non conventional machine tools, compared to conventional machining, has forced us to operate these machines as efficiently as possible in order to reduce production cost and to obtain the required reimbursement. To achieve this task, machining parameters such as pulse on time, pulse off time, discharge current, gap voltage, flushing pressure, electrode material, etc. of this process should be selected such that optimal value of their performance measures like Material Removal Rate (MRR, Surface Roughness (SR, Electrode/Tool Wear Rate (EWR/TWR, dimensional accuracy, etc. can be obtained or improved. In past decades, intensive research work had been carried out by different researchers for improvement and optimization of EDM performance measures using various optimization techniques like Taguchi, Response Surface Methodology (RSM, Artificial Neural Network (ANN, Genetic Algorithm (GA, etc. This paper reviews research on improvement and optimization of various performance measures of spark erosion EDM and finally lists down certain areas that can be taken up for further research in the field of improvement and optimization for EDM process.

  16. Effects of Electric Vehicle Fast Charging on Battery Life and Vehicle Performance

    Energy Technology Data Exchange (ETDEWEB)

    Matthew Shirk; Jeffrey Wishart

    2015-04-01

    As part of the U.S. Department of Energy’s Advanced Vehicle Testing Activity, four new 2012 Nissan Leaf battery electric vehicles were instrumented with data loggers and operated over a fixed on-road test cycle. Each vehicle was operated over the test route, and charged twice daily. Two vehicles were charged exclusively by AC level 2 EVSE, while two were exclusively DC fast charged with a 50 kW charger. The vehicles were performance tested on a closed test track when new, and after accumulation of 50,000 miles. The traction battery packs were removed and laboratory tested when the vehicles were new, and at 10,000-mile intervals. Battery tests include constant-current discharge capacity, electric vehicle pulse power characterization test, and low peak power tests. The on-road testing was carried out through 70,000 miles, at which point the final battery tests were performed. The data collected over 70,000 miles of driving, charging, and rest are analyzed, including the resulting thermal conditions and power and cycle demands placed upon the battery. Battery performance metrics including capacity, internal resistance, and power capability obtained from laboratory testing throughout the test program are analyzed. Results are compared within and between the two groups of vehicles. Specifically, the impacts on battery performance, as measured by laboratory testing, are explored as they relate to battery usage and variations in conditions encountered, with a primary focus on effects due to the differences between AC level 2 and DC fast charging. The contrast between battery performance degradation and the effect on vehicle performance is also explored.

  17. Effect of machining fluid on the process performance of wire electrical discharge machining of nanocomposite ceramic

    Directory of Open Access Journals (Sweden)

    Zhang Chengmao

    2015-01-01

    Full Text Available Wire electric discharge machining (WEDM promise to be effective and economical techniques for the production of tools and parts from conducting ceramic blanks. However, the manufacturing of nanocomposite ceramics blanks with these processes is a long and costly process. This paper presents a new process of machining nanocomposite ceramics using WEDM. WEDM uses water based emulsion, polyvinyl alcohol and distilled water as the machining fluid. Machining fluid is a primary factor that affects the material removal rate and surface quality of WEDM. The effects of emulsion concentration, polyvinyl alcohol concentration and distilled water of the machining fluid on the process performance have been investigated.

  18. Effects of Electric and Magnetic Fields on the Performance of a Superconducting Cavity

    Energy Technology Data Exchange (ETDEWEB)

    Gianluigi Ciovati; Peter Kneisel; Jacek Sekutowicz; Waldemar Singer

    2005-05-01

    A special two-cell cavity was designed to obtain surface field distributions suitable for investigation of electric and magnetic field effects on cavity performance. The cavity design and preliminary results were presented in a previous contribution. The bulk niobium cavity was heat-treated in a vacuum furnace at 1250 C to improve thermal conductivity. Three seamless hydroformed Nb/Cu cavities of the same design were fabricated to investigate the role of the electron beam welds located in high field areas. This paper will present RF test results at 2 K for the bulk niobium and one of the seamless cavities.

  19. Results of electric-vehicle propulsion system performance on three lead-acid battery systems

    Science.gov (United States)

    Ewashinka, J. G.

    1984-01-01

    Three types of state of the art 6 V lead acid batteries were tested. The cycle life of lead acid batteries as a function of the electric vehicle propulsion system design was determined. Cycle life, degradation rate and failure modes with different battery types (baseline versus state of the art tubular and thin plate batteries were compared. The effects of testing strings of three versus six series connected batteries on overall performance were investigated. All three types do not seem to have an economically feasible battery system for the propulsion systems. The tubular plate batteries on the load leveled profile attained 235 cycles with no signs of degradation and minimal capacity loss.

  20. Electrical performances of pyroelectric bimetallic strip heat engines describing a Stirling cycle

    Science.gov (United States)

    Arnaud, A.; Boughaleb, J.; Monfray, S.; Boeuf, F.; Cugat, O.; Skotnicki, T.

    2015-12-01

    This paper deals with the analytical modeling of pyroelectric bimetallic strip heat engines. These devices are designed to exploit the snap-through of a thermo-mechanically bistable membrane to transform a part of the heat flowing through the membrane into mechanical energy and to convert it into electric energy by means of a piezoelectric layer deposited on the surface of the bistable membrane. In this paper, we describe the properties of these heat engines in the case when they complete a Stirling cycle, and we evaluate the performances (available energy, Carnot efficiency...) of these harvesters at the macro- and micro-scale.

  1. Performance evaluation of CO-OFDM systems based on electrical constant-envelope signals

    Science.gov (United States)

    Dias, Vinicius O. C.; Pereira, Ezequiel da V.; Rocha, Helder R. O.; Segatto, Marcelo E. V.; Silva, Jair A. L.

    2017-09-01

    The influence of the electrical phase modulation index h in the performance of constant-envelope orthogonal frequency division multiplexing (CE-OFDM) in coherent detection optical systems is treated analytically and its range of validity examined by simulations. A compromise between h and subcarrier mapping is identified according to differences in sensitivity related to non-linearities inserted by the optical modulator. It is shown that the proposed scheme outperforms conventional coherent detection OFDM systems, which is strongly dependent on both phase and optical modulation indexes.

  2. Ecological performance of electrical consumer products: the influence of automation and information-based measures.

    Science.gov (United States)

    Sauer, Juergen; Wiese, Bettina S; Rüttinger, Bruno

    2004-01-01

    Being concerned with the environmental impact of electrical consumer products, this article examines possibilities of influencing ecological user performance through design features. Furthermore, it looks at the relationship of user characteristics and ecological performance. The impact of level of automation and type of control labelling on ecological user performance was examined in a lab-based experimental scenario with 36 users. In addition to performance indicators, a range of user variables (e.g., self-reported domestic behaviour, environmental knowledge and attitude) was measured to assess their influence on user behaviour. The results showed that low-level automation improved ecological performance whereas no such positive effect was observed for enhanced display-control labelling. Furthermore, the results suggested that the user's mental model of ecological performance was rather limited. No relationship was found between environmental knowledge, attitude and performance. The findings pointed at the strong prevalence of habits in the domestic domain. The implications of the results for designers of consumer products are discussed.

  3. Electrical characterization of fluorinated benzothiadiazole based conjugated copolymer – a promising material for high-performance solar cells

    DEFF Research Database (Denmark)

    Toušek, J.; Toušková, J.; Remeš, Z.;

    2015-01-01

    Measurements of electrical conductivity, electron work function, carrier mobility ofholes and the diffusion length of excitons were performed on samples of conjugatedpolymers relevant to polymer solar cells. A state of the art fluorinated benzothiadiazolebased conjugated copolymer (PBDTTHD − DTBTff...

  4. High density near amorphous InSb nanowire arrays and its photo-electric performance

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Ming, E-mail: mfang@issp.ac.cn [Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanostructure, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Tan, Xiaoli [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Liu, Mao, E-mail: mliu@issp.ac.cn [Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanostructure, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Gong, Xinxin; Zhang, Lide; Fei, Guangtao [Key Laboratory of Materials Physics, Anhui Key Laboratory of Nanomaterials and Nanostructure, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China)

    2015-03-25

    Highlights: • InSb near amorphous nanowire arrays are successfully fabricated. • The 30 nm diameter nanowire array shows a well infrared photo-electric response, and the reasons are discussed. • The reason for the black color of the InSb semiconductor is discussed. - Abstract: In this paper, we report the fabrication of high density near amorphous InSb nanowire arrays with using 30, 55 and 70 nm diameter anodic alumina oxide (AAO) template by electrodeposition method. The near amorphous structure was proved by combining the results of X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). Different from the bulk material, these nanowires are black and could not be analyzed by the traditional method, and the reason was discussed. By testing of the photo-electric performance, the 30 nm diameter InSb nanowire showed the best performance, which could be used at about 260 K. The formation of the near amorphous structure was also discussed. Such high density nanoarrays may found potential application in the infrared detection field.

  5. Electrical Performance of a High Temperature 32-I/O HTCC Alumina Package

    Science.gov (United States)

    Chen, Liang-Yu; Neudeck, Philip G.; Spry, David J.; Beheim, Glenn M.; Hunter, Gary W.

    2016-01-01

    A high temperature co-fired ceramic (HTCC) alumina material was previously electrically tested at temperatures up to 550 C, and demonstrated improved dielectric performance at high temperatures compared with the 96% alumina substrate that we used before, suggesting its potential use for high temperature packaging applications. This paper introduces a prototype 32-I/O (input/output) HTCC alumina package with platinum conductor for 500 C low-power silicon carbide (SiC) integrated circuits. The design and electrical performance of this package including parasitic capacitance and parallel conductance of neighboring I/Os from 100 Hz to 1 MHz in a temperature range from room temperature to 550 C are discussed in detail. The parasitic capacitance and parallel conductance of this package in the entire frequency and temperature ranges measured does not exceed 1.5 pF and 0.05 microsiemens, respectively. SiC integrated circuits using this package and compatible printed circuit board have been successfully tested at 500 C for over 3736 hours continuously, and at 700 C for over 140 hours. Some test examples of SiC integrated circuits with this packaging system are presented. This package is the key to prolonged T greater than or equal to 500 C operational testing of the new generation of SiC high temperature integrated circuits and other devices currently under development at NASA Glenn Research Center.

  6. Non-contact assessment of electrical performance for rapidly sintered nanoparticle silver coatings through colorimetry

    Energy Technology Data Exchange (ETDEWEB)

    Cherrington, M.; Claypole, T.C.; Gethin, D.T. [Welsh Centre for Printing and Coating, College of Engineering, Swansea University, Singleton Park, Swansea, SA2 8PP (United Kingdom); Worsley, D.A. [SPECIFIC, College of Engineering, Swansea University, Baglan Bay Innovation Centre, Central Avenue, Baglan Energy Park, Port Talbot, SA12 7AX (United Kingdom); Deganello, D., E-mail: d.deganello@swansea.ac.uk [Welsh Centre for Printing and Coating, College of Engineering, Swansea University, Singleton Park, Swansea, SA2 8PP (United Kingdom)

    2012-11-01

    The color change during the ultrafast near-infrared sintering process of a nanoparticle silver ink has been correlated to its electrical performance through colorimetry using the CIELAB industry standard. Nanoparticle silver ink films, deposited over a flexible polyethylene terephthalate substrate, presented significant shifting in the a* and b* color coordinates during sintering, exhibiting the best conductivity with an a* coordinate of approximately 0 and a b* coordinate of approximately + 10. This color change has been associated with the Lorenz-Mie theory of electromagnetic scattering. This indirect measurement technique is potentially a breakthrough technology for fast in-line non-contact characterization of the drying and sintering process of nanoparticle conductive inks for use in large area roll-to-roll processing of printed electronics. - Highlights: Black-Right-Pointing-Pointer Color change of a nanoparticle silver coating was measured during sintering Black-Right-Pointing-Pointer Color change was correlated to the electrical performance of the coating. Black-Right-Pointing-Pointer Potential in-line non-contact measurement method for roll-to-roll printed electronics.

  7. Power Management Strategy of Hybrid Electric Vehicles Based on Quadratic Performance Index

    Directory of Open Access Journals (Sweden)

    Chaoying Xia

    2015-11-01

    Full Text Available An energy management strategy (EMS considering both optimality and real-time performance has become a challenge for the development of hybrid electric vehicles (HEVs in recent years. Previous EMSes based on the optimal control theory minimize the fuel consumption, but cannot be directly implemented in real-time because of the requirement for a prior knowledge of the entire driving cycle. This paper presents an innovative design concept and method to obtain a power management strategy for HEVs, which is independent of future driving conditions. A quadratic performance index is designed to ensure the vehicle drivability, maintain the battery energy sustainability and average and smooth the engine power and motor power to indirectly reduce fuel consumption. To further improve the fuel economy, two rules are adopted to avoid the inefficient engine operation by switching control modes between the electric and hybrid modes according to the required driving power. The derived power of the engine and motor are related to current vehicle velocity and battery residual energy, as well as their desired values. The simulation results over different driving cycles in Advanced Vehicle Simulator (ADVISOR show that the proposed strategy can significantly improve the fuel economy, which is very close to the optimal strategy based on Pontryagin’s minimum principle.

  8. DOE ETV-1 electric test vehicle. Phase III: performance testing and system evaluation. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, D. W.

    1981-12-01

    The DOE ETV-1 represents the most advanced electric vehicle in operation today. Engineering tests have been conducted by the Jet Propulsion Laboratory in order to characterize its overall system performance and component efficiencies within the system environment. A dynamometer was used in order to minimize the ambient effects and large uncertainties present in track testing. Extensive test requirements have been defined and procedures were carefully controlled in order to maintain a high degree of credibility. Limited track testing was performed in order to corroborate the dynamometer results. Test results include an energy flow analysis through the major subsystems and incorporate and aerodynamic and rolling losses under cyclic and various steady speed conditions. A complete summary of the major output from all relevant dynamometer and track tests is also included as an appendix.

  9. DOE ETV-1 electric test vehicle. Phase III: performance testing and system evaluation. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, D. W.

    1981-12-01

    The DOE ETV-1 represents the most advanced electric vehicle in operation today. Engineering tests have been conducted by the Jet Propulsion Laboratory in order to characterize its overall system performance and component efficiencies within the system environment. A dynamometer was used in order to minimize the ambient effects and large uncertainties present in track testing. Extensive test requirements have been defined and procedures were carefully controlled in order to maintain a high degree of credibility. Limited track testing was performed in order to corroborate the dynamometer results. Test results include an energy flow analysis through the major subsystems and incorporate and aerodynamic and rolling losses under cyclic and various steady speed conditions. A complete summary of the major output from all relevant dynamometer and track tests is also included as an appendix.

  10. Electrical circuit models for performance modeling of Lithium-Sulfur batteries

    DEFF Research Database (Denmark)

    Knap, Vaclav; Stroe, Daniel Ioan; Teodorescu, Remus

    2015-01-01

    Energy storage technologies such as Lithium-ion (Li-ion) batteries are widely used in the present effort to move towards more ecological solutions in sectors like transportation or renewable-energy integration. However, today's Li-ion batteries are reaching their limits and not all demands...... of the industry are met yet. Therefore, researchers focus on alternative battery chemistries as Lithium-Sulfur (Li-S), which have a huge potential due to their high theoretical specific capacity (approx. 1675 Ah/kg) and theoretical energy density of almost 2600 Wh/kg. To analyze the suitability of this new...... emerging technology for various applications, there is a need for Li-S battery performance model; however, developing such models represents a challenging task due to batteries' complex ongoing chemical reactions. Therefore, the literature review was performed to summarize electrical circuit models (ECMs...

  11. Control system design for electrical stimulation in upper limb rehabilitation modelling, identification and robust performance

    CERN Document Server

    Freeman, Chris

    2016-01-01

    This book presents a comprehensive framework for model-based electrical stimulation (ES) controller design, covering the whole process needed to develop a system for helping people with physical impairments perform functional upper limb tasks such as eating, grasping and manipulating objects. The book first demonstrates procedures for modelling and identifying biomechanical models of the response of ES, covering a wide variety of aspects including mechanical support structures, kinematics, electrode placement, tasks, and sensor locations. It then goes on to demonstrate how complex functional activities of daily living can be captured in the form of optimisation problems, and extends ES control design to address this case. It then lays out a design methodology, stability conditions, and robust performance criteria that enable control schemes to be developed systematically and transparently, ensuring that they can operate effectively in the presence of realistic modelling uncertainty, physiological variation an...

  12. Emprego de uma abordagem multicritério para classificação do desempenho de instituições de ensino superior Utilización de una metodología multicriterio para la clasificación del desempeño de instituciones de educación superior Using a multicriteria approach for classifying universities' performance

    Directory of Open Access Journals (Sweden)

    André Luís Policani Freitas

    2009-12-01

    Ponderada para clasificar el funcionamiento de las Instituciones de Educación Superior segundo la opinión de profesores y estudiantes. Con el deseo de investigar el uso de esta metodología, fue realizado un experimento en una universidad publica - el análisis de los resultados y algunas conclusiones son presentadas. Las potencialidades/debilidades y los puntos críticos que se deben dar la prioridad a favor de la mejora de la Calidad en la Educación fueran identificados.Since the 90's, the Brazilian University System has experienced a fast growth, which is characterized by the increasing quantity of Universities and University Degree Courses. In this context, it's essential that exists an efficient Education Evaluation System to monitor the information of these universities and to assure that the education quality provided by them achieve the recommended standards. One way to get the Education System efficiency is to continuously evaluate the performance of Universities concerning several criteria. Thus, this work presents a multicriteria approach based on the traditional Weighted Average method for sorting the universities performance according to professors and students points of view. In order to investigate the application of this approach, a case study was conducted in a Public university. The weaknesses/potentialities and the critical points which must be prioritized in order to improve the Education Quality were identified.

  13. State Performance-Based Regulation Using Multiyear Rate Plans for U.S. Electric Utilities

    Energy Technology Data Exchange (ETDEWEB)

    Lowry, Mark Newton [Pacific Economics Group Research LLC (United States); Makos, Matt [Pacific Economics Group Research LLC (United States); Deason, Jeff [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Schwartz, Lisa [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2017-07-31

    Electric utilities today must contain costs at a time when many need to modernize aging systems and all face major changes in technologies, customer preferences and competitive pressures.Most U.S. electric utility facilities are investor-owned, subject to rate and service regulation by state public utility commissions. Regulatory systems under which these utilities operate affect their performance and ability to meet these challenges. In this business environment, multiyear rate plans have some advantages over traditional rate regulation.The report focuses on key design issues and provides case studies of the multiyear rate plan approach, applicable to both vertically integrated and restructured states. Mark Newton Lowry and Matt Makos of Pacific Energy Group Research and Jeff Deason of Berkeley Lab authored the report; Lisa Schwartz, Berkeley Lab, was project manager and technical editor.The report is aimed primarily at state utility regulators and stakeholders in the state regulatory process. The multiyear rate approach also provides ideas on how to streamline oversight of public power utilities and rural electric cooperatives for their governing boards.Two key provisions of multiyear rate plans strengthen cost containment incentives and streamline regulation: 1. Reducing frequency of rate cases, typically to every four or five years 2. Using an attrition relief mechanism to escalate rates or revenue between rate cases to address cost pressures such as inflation and growth in number of customers, independently of the utility’s own cost Better utility performance can be achieved under well-designed multiyear rate plans while achieving lower regulatory costs. Benefits can be shared between utilities and their customers. But plans can be complex and involve significant changes in the regulatory system. Designing plans that stimulate utility performance without undue risk and share benefits fairly can be challenging.This report discusses the rationale for multiyear

  14. Superior Hiking Trail

    Data.gov (United States)

    Minnesota Department of Natural Resources — Superior Hiking Trail main trail, spurs, and camp spurs for completed trail throughout Cook, Lake, St. Louis and Carlton counties. These data were collected with...

  15. Bathymetry of Lake Superior

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Superior has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  16. Superior Hiking Trail Facilities

    Data.gov (United States)

    Minnesota Department of Natural Resources — Superior Hiking Trail main trail, spurs, and camp spurs for completed trail throughout Cook, Lake, St. Louis and Carlton counties. These data were collected with...

  17. Direct yaw moment control for distributed drive electric vehicle handling performance improvement

    Science.gov (United States)

    Yu, Zhuoping; Leng, Bo; Xiong, Lu; Feng, Yuan; Shi, Fenmiao

    2016-05-01

    For a distributed drive electric vehicle (DDEV) driven by four in-wheel motors, advanced vehicle dynamic control methods can be realized easily because motors can be controlled independently, quickly and precisely. And direct yaw-moment control (DYC) has been widely studied and applied to vehicle stability control. Good vehicle handling performance: quick yaw rate transient response, small overshoot, high steady yaw rate gain, etc, is required by drivers under normal conditions, which is less concerned, however. Based on the hierarchical control methodology, a novel control system using direct yaw moment control for improving handling performance of a distributed drive electric vehicle especially under normal driving conditions has been proposed. The upper-loop control system consists of two parts: a state feedback controller, which aims to realize the ideal transient response of yaw rate, with a vehicle sideslip angle observer; and a steering wheel angle feedforward controller designed to achieve a desired yaw rate steady gain. Under the restriction of the effect of poles and zeros in the closed-loop transfer function on the system response and the capacity of in-wheel motors, the integrated time and absolute error (ITAE) function is utilized as the cost function in the optimal control to calculate the ideal eigen frequency and damper coefficient of the system and obtain optimal feedback matrix and feedforward matrix. Simulations and experiments with a DDEV under multiple maneuvers are carried out and show the effectiveness of the proposed method: yaw rate rising time is reduced, steady yaw rate gain is increased, vehicle steering characteristic is close to neutral steer and drivers burdens are also reduced. The control system improves vehicle handling performance under normal conditions in both transient and steady response. State feedback control instead of model following control is introduced in the control system so that the sense of control intervention to

  18. The Effect of Electric Load Profiles on the Performance of Off-Grid Residential Hybrid Renewable Energy Systems

    Directory of Open Access Journals (Sweden)

    Stephen Treado

    2015-10-01

    Full Text Available This paper investigates the energy performance of off-grid residential hybrid renewable electric power systems, particularly the effect of electric load profiles on the ability to harvest available solar energy and avoid the consumption of auxiliary energy in the form of propane. The concepts are illustrated by an analysis of the energy performance of electric and propane-fired refrigerators. Off-grid electric power systems frequently incorporate a renewable source, such as wind or solar photovoltaic (PV, with a back-up power provided by a propane fueled motor/generator. Among other design decisions, residential consumers face the choice of employing an electric refrigerator with a conventional vapor compression refrigeration system, or a fuel-fired refrigerator operating as an absorption refrigeration system. One interesting question is whether it is more advantageous from an energy perspective to use electricity to run the refrigerator, which might be provided by some combination of the PV and propane motor/generator, thereby taking advantage of the relatively higher electric refrigerator Coefficient of Performance (COP and free solar energy but having to accept a low electrical conversion efficiency of the motor/generator, or use thermal energy from the combustion of propane to produce the refrigeration effect via an absorption system, albeit with a much lower COP. The analysis is complicated by the fact that most off-grid renewable electrical power systems utilize a battery bank to provide electrical power when it is not available from the wind turbine or PV system, so the state of charge of the battery bank will have a noticeable impact on what energy source is available at any moment in time. Daily electric load profiles combined with variable solar energy input determine the state of charge of the battery bank, with the degree of synchronization between the two being a critical factor in determining performance. The annual energy usage

  19. Optical and Electrical Performance of ZnO Films Textured by Chemical Etching

    Directory of Open Access Journals (Sweden)

    Shiuh-Chuan HER

    2015-11-01

    Full Text Available Zinc oxide (ZnO films were prepared by radio frequency (RF magnetron sputtering on the glass substrate as transparent conductive oxide films. For silicon solar cells, a proper surface texture is essential to introduce light scattering and subsequent light trapping to enhance the current generation. In this study, the magnetron-sputtered ZnO films were textured by wet-chemical etching in diluted hydrochloric acid (HCl for better light scattering. The diffuse transmittance of the surface textured ZnO films was measured to evaluate the light scattering. The influence of hydrochloric acid concentration on the morphology, optical and electrical properties of the surface-textured ZnO film was investigated. The ZnO film etched in 0.05M HCl solution for 30 s exhibited average diffuse transmittance in the visible wavelength range of 9.52 % and good resistivity of 1.10 x 10-3 W×cm while the as-deposited ZnO film had average diffuse transmittance of 0.51 % and relatively high resistivity of 5.84 x 10-2 W×cm. Experimental results illustrated that the optical and electrical performance of ZnO films can be significantly improved by introducing the surface texture through the wet-chemical etching process.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9624

  20. Surface performance of workpieces processed by electrical discharge machining in gas

    Institute of Scientific and Technical Information of China (English)

    LI Li-qing; BAI Ji-cheng; GUO Yong-feng; WANG Zhen-long

    2009-01-01

    The surface performance of workpieces processed by electrical discharge machining in gas (dry EDM) was studied in this paper. Firstly, the composition, micro hardness and recast layer of electrical discharge machined (EDMed) surface of 45 carbon steels in air were investigated through different test analysis methods. The results show that the workpiece surface EDMed in air contains a certain quantity of oxide, and oxidation occurs on the workpiece surface. Compared with the surface of workpieces processed in kerosene, fewer cracks exist on the dry EDMed workpiece surface, and the surface recast layer is thinner than that obtained by conventional EDM. The micro hardness of workpieces machined by dry EDM method is lower than that machined in kerosene, and higher than that of the matrix. In addition, experiments were conducted on the surface wear resistance of workpieces processed in air and kerosene using copper electrode and titanium alloy electrode.The results indicate that the surface wear resistance of workpieces processed in air can be improved, and it is related with tool material and dielectric.

  1. Boosted output performance of triboelectric nanogenerator via electric double layer effect

    Science.gov (United States)

    Chun, Jinsung; Ye, Byeong Uk; Lee, Jae Won; Choi, Dukhyun; Kang, Chong-Yun; Kim, Sang-Woo; Wang, Zhong Lin; Baik, Jeong Min

    2016-10-01

    For existing triboelectric nanogenerators (TENGs), it is important to explore unique methods to further enhance the output power under realistic environments to speed up their commercialization. We report here a practical TENG composed of three layers, in which the key layer, an electric double layer, is inserted between a top layer, made of Al/polydimethylsiloxane, and a bottom layer, made of Al. The efficient charge separation in the middle layer, based on Volta's electrophorus, results from sequential contact configuration of the TENG and direct electrical connection of the middle layer to the earth. A sustainable and enhanced output performance of 1.22 mA and 46.8 mW cm-2 under low frequency of 3 Hz is produced, giving over 16-fold enhancement in output power and corresponding to energy conversion efficiency of 22.4%. Finally, a portable power-supplying system, which provides enough d.c. power for charging a smart watch or phone battery, is also successfully developed.

  2. Multiple performance characteristics optimization for Al 7075 on electric discharge drilling by Taguchi grey relational theory

    Science.gov (United States)

    Khanna, Rajesh; Kumar, Anish; Garg, Mohinder Pal; Singh, Ajit; Sharma, Neeraj

    2015-05-01

    Electric discharge drill machine (EDDM) is a spark erosion process to produce micro-holes in conductive materials. This process is widely used in aerospace, medical, dental and automobile industries. As for the performance evaluation of the electric discharge drilling machine, it is very necessary to study the process parameters of machine tool. In this research paper, a brass rod 2 mm diameter was selected as a tool electrode. The experiments generate output responses such as tool wear rate (TWR). The best parameters such as pulse on-time, pulse off-time and water pressure were studied for best machining characteristics. This investigation presents the use of Taguchi approach for better TWR in drilling of Al-7075. A plan of experiments, based on L27 Taguchi design method, was selected for drilling of material. Analysis of variance (ANOVA) shows the percentage contribution of the control factor in the machining of Al-7075 in EDDM. The optimal combination levels and the significant drilling parameters on TWR were obtained. The optimization results showed that the combination of maximum pulse on-time and minimum pulse off-time gives maximum MRR.

  3. Electrically engineered polymer-carbon hybrid heterojunction for high-performance printed transistors

    Science.gov (United States)

    Kim, Do Hwan; Kang, Gyu Won; Shin, Hyeon-Jin; Kim, Woo-Jae

    2014-10-01

    Molecularly hybridized materials composed of polymer semiconductors (PSCs) and single-walled carbon nanotubes (SWNTs) may provide a new platform to exploit an advantageous combination of semiconductors, which yields electrical properties that are not available in a single component system. In this talk, we demonstrate high-performance ink-jet printed hybrid transistors with an electrically engineered heterostructure by using specially designed PSCs and semiconducting SWNTs (sc-SWNTs) whose system achieved a high mobility of 0.23 cm2V-1s-1, no Von shift, a low off-current, and good bias-stability. We also revealed that binding energy between PSCs and sc-SWNT was strongly affected by side-chain length of PSCs, leading to the formation of homogeneous nanohybrid film. Eventually, understanding of electrostatic interactions in the heterostructure and experimental results suggest criteria for the design of nanohybrid heterostructures. Acknowledgement. This work was supported by a grant (Code No. 2011-0031628) from the Center for Advanced Soft Electronics under the Global Frontier Research Program of the Ministry of Science, ICT and Future Planning, Korea. The authors acknowledge Prof. Kilwon Cho for collaboration on the analysis of x-ray diffraction.

  4. Modeling and Performance Prediction of Induction Motor Drive System for Electric Drive Tracked Vehicles

    Institute of Scientific and Technical Information of China (English)

    CHEN Shu-yong; CHEN Quan-shi; SUN Feng-chun

    2007-01-01

    The principle of rotor flux-orientation vector control on 100/150 kW three-phase AC induction motor for electric drive tracked vehicles is analyzed, and the mathematic model is deduced. The drive system of induction motor is modeled and simulated by Matlab/Simulink. The characteristics of motor and drive system are analyzed and evaluated by practical bench test. The simulation and bench test results show that the model is valid, and the driving control system has constant torque under rated speed, constant torque above rated speed, widely variable speed range and better dynamic characteristics. In order to evaluate the practical applications of high power induction motor driving system in electric drive tracked vehicles, a collaborative simulation based on interface technology of Matlab/Simulink and multi-body dynamic analysis software known as RecurDyn is done, the vehicle performances are predicted in the acceleration time (0-32 km/h) and turning characteristic (v=10 km/h, R=B).

  5. Design and Performance of the NASA SCEPTOR Distributed Electric Propulsion Flight Demonstrator

    Science.gov (United States)

    Borer, Nicholas K.; Patterson, Michael D.; Viken, Jeffrey K.; Moore, Mark D.; Clarke, Sean; Redifer, Matthew E.; Christie, Robert J.; Stoll, Alex M.; Dubois, Arthur; Bevirt, JoeBen; hide

    2016-01-01

    Distributed Electric Propulsion (DEP) technology uses multiple propulsors driven by electric motors distributed about the airframe to yield beneficial aerodynamic-propulsion interaction. The NASA SCEPTOR flight demonstration project will retrofit an existing internal combustion engine-powered light aircraft with two types of DEP: small "high-lift" propellers distributed along the leading edge of the wing which accelerate the flow over the wing at low speeds, and larger cruise propellers co-located with each wingtip for primary propulsive power. The updated high-lift system enables a 2.5x reduction in wing area as compared to the original aircraft, reducing drag at cruise and shifting the velocity for maximum lift-to-drag ratio to a higher speed, while maintaining low-speed performance. The wingtip-mounted cruise propellers interact with the wingtip vortex, enabling a further efficiency increase that can reduce propulsive power by 10%. A tradespace exploration approach is developed that enables rapid identification of salient trades, and subsequent creation of SCEPTOR demonstrator geometries. These candidates were scrutinized by subject matter experts to identify design preferences that were not modeled during configuration exploration. This exploration and design approach is used to create an aircraft that consumes an estimated 4.8x less energy at the selected cruise point when compared to the original aircraft.

  6. High-frequency performance of electric field sensors aboard the RESONANCE satellite

    Science.gov (United States)

    Sampl, M.; Macher, W.; Gruber, C.; Oswald, T.; Kapper, M.; Rucker, H. O.; Mogilevsky, M.

    2015-05-01

    We present the high-frequency properties of the eight electric field sensors as proposed to be launched on the spacecraft "RESONANCE" in the near future. Due to the close proximity of the conducting spacecraft body, the sensors (antennas) have complex receiving features and need to be well understood for an optimal mission and spacecraft design. An optimal configuration and precise understanding of the sensor and antenna characteristics is also vital for the proper performance of spaceborne scientific instrumentation and the corresponding data analysis. The provided results are particularly interesting with regard to the planned mutual impedance experiment for measuring plasma parameters. Our computational results describe the extreme dependency of the sensor system with regard to wave incident direction and frequency, and provides the full description of the sensor system as a multi-port scatterer. In particular, goniopolarimetry techniques like polarization analysis and direction finding depend crucially on the presented antenna characteristics.

  7. Solar thermal electric power plants - Their performance characteristics and total social costs

    Science.gov (United States)

    Caputo, R. S.; Truscello, V. C.

    1976-01-01

    The central receiver (power tower) concept as a thermal conversion approach to the conversion of solar energy into electricity is compared to other solar power plant designs which feature distributed solar collection and use other types of solar collector configurations. A variety of solar thermal storage concepts are discussed and their impacts on system performance are assessed. Although a good deal of quantification is possible in a comparative study, the subjective judgments carry enormous weight in a socio-economic decision, the ultimate choice of central power plant being more a social than an economic or technical decision. Major elements of the total social cost of each type of central plant are identified as utility economic costs, R&D funds, health costs, and other relevant social impacts.

  8. Advances in three-dimensional field analysis and evaluation of performance parameters of electrical machines

    Science.gov (United States)

    Sivasubramaniam, Kiruba

    This thesis makes advances in three dimensional finite element analysis of electrical machines and the quantification of their parameters and performance. The principal objectives of the thesis are: (1)the development of a stable and accurate method of nonlinear three-dimensional field computation and application to electrical machinery and devices; and (2)improvement in the accuracy of determination of performance parameters, particularly forces and torque computed from finite elements. Contributions are made in two general areas: a more efficient formulation for three dimensional finite element analysis which saves time and improves accuracy, and new post-processing techniques to calculate flux density values from a given finite element solution. A novel three-dimensional magnetostatic solution based on a modified scalar potential method is implemented. This method has significant advantages over the traditional total scalar, reduced scalar or vector potential methods. The new method is applied to a 3D geometry of an iron core inductor and a permanent magnet motor. The results obtained are compared with those obtained from traditional methods, in terms of accuracy and speed of computation. A technique which has been observed to improve force computation in two dimensional analysis using a local solution of Laplace's equation in the airgap of machines is investigated and a similar method is implemented in the three dimensional analysis of electromagnetic devices. A new integral formulation to improve force calculation from a smoother flux-density profile is also explored and implemented. Comparisons are made and conclusions drawn as to how much improvement is obtained and at what cost. This thesis also demonstrates the use of finite element analysis to analyze torque ripples due to rotor eccentricity in permanent magnet BLDC motors. A new method for analyzing torque harmonics based on data obtained from a time stepping finite element analysis of the machine is

  9. Electricity consumers under the state and the private sector: comparing the price performance of the French and UK electricity industries 1990-2000

    Energy Technology Data Exchange (ETDEWEB)

    Percebois, Jacques [Univ. de Montpellier 1, CREDEN, Montpelier, 34 (France); Wright, Philip [Sheffield Univ., Management School, Sheffield (United Kingdom)

    2001-12-01

    Particularly because a preoccupation with process has tended to dominate the debate about electricity privatisation and liberalisation, this paper focuses on price outcomes by comparing the relative price performance of the French and UK electricity industries between 1990 and 2000. The main conclusion is that in 1990 the state-owned French electricity industry was performing better for most consumers than the state-owned UK industry, and a decade later it was still doing so with respect to the privately-owned UK industry. While this conclusion could be qualified by saying that, heavily prompted or assisted by the Regulator, the UK privately-owned industry has shown itself capable of achieving faster reductions in prices to close the gap between itself and the French, this achievement has been concentrated in the industrial market and even there the very significant gains were mainly restricted to the very largest consumers. In the context of the European Union the UK is shown to have performed relatively poorly for the smallest domestic consumers and, while both countries did much better in the rankings of industrial prices, they were still a long way behind the top performers. (Author)

  10. The performance and efficiency of four motor/controller/battery systems for the simpler electric vehicles

    Science.gov (United States)

    Shipps, P. R.

    1980-05-01

    A test and analysis program performed on four complete propulsion systems for an urban electric vehicle (EV) is described and results given. A dc series motor and a permanent magnet (PM) motor were tested, each powered by an EV battery pack and controlled by (1) a series/parallel voltage-switching (V-switch) system; and (2) a system using a pulse width modulation, 400 Hz transistorized chopper. Dynamometer tests were first performed, followed by eV performance predictions and data correlating road tests. During dynamometer tests using chopper control; current, voltage, and power were measured on both the battery and motor sides of the chopper, using three types of instrumentation. Conventional dc instruments provided adequate accuracy for eV power and energy measurements, when used on the battery side of the controller. When using the chopper controller, the addition of a small choke inductor improved system efficiency in the lower duty cycle range (some 8% increase at 50% duty cycle) with both types of motors. Overall system efficiency rankings during road tests were: (1) series motor with V-switch; (2) PM motor with V-switch; (3) series motor with chopper; and (4) PM motor with chopper. Chopper control of the eV was smoother and required less driver skill than V-switch control.

  11. The effects of regional insolation differences upon advanced solar thermal electric power plant performance and energy costs

    Science.gov (United States)

    Latta, A. F.; Bowyer, J. M.; Fujita, T.; Richter, P. H.

    1980-01-01

    The performance and cost of four 10 MWe advanced solar thermal electric power plants sited in various regions of the continental United States was studied. Each region has different insolation characteristics which result in varying collector field areas, plant performance, capital costs and energy costs. The regional variation in solar plant performance was assessed in relation to the expected rise in the future cost of residential and commercial electricity supplied by conventional utility power systems in the same regions. A discussion of the regional insolation data base is presented along with a description of the solar systems performance and costs. A range for the forecast cost of conventional electricity by region and nationally over the next several decades is given.

  12. The Evaluation of Energy Conservation Performance on Electricity: A Case Study of the TFT-LCD Optronics Industry

    Directory of Open Access Journals (Sweden)

    Ven-Shing Wang

    2016-03-01

    Full Text Available This study describes the performance evaluation of an energy management system, based on electricity consumption, for a Gen 6 Thin Film Transistor Liquid Crystal Display (TFT-LCD panel plant. Of the various production lines and facility systems, the array system and the compressed dry air consumed the most electricity of 21.8% and 19.8%, respectively, while the public utility used only 1.6% of the total electricity. The baseline electricity consumptions were correlated well (R2 ≥ 0.77 to the monthly average wet-bulb temperatures of ambient air and the panel yield rates, which were determined by the product yield over the equipment available time index. After implementing the energy saving projects, the energy conservation performance was determined using a three-parameter change-point regression model incorporated with the panel yield rates. The post-retrofit monthly savings of the total electricity consumption for the panel manufacture were 5.35%–10.36%, with the efficiency of the electricity performance revealing an upswing trend following the implementation of the energy management system.

  13. PERSISTENT LEFT SUPERIOR VENACAVA

    Directory of Open Access Journals (Sweden)

    Devinder Singh

    2014-05-01

    Full Text Available A Persistent Left Superior Venacava (PLSVC is the most common variation of the thoracic venous system and rare congenital vascular anomaly and is prevalent in 0.3% of the population. It may be associated with other cardiovascular abnormalities including atrial septal defect, bicuspid aortic valve, coarctation of aorta, coronary sinus ostial atresia, and cor triatriatum. Incidental rotation of a dilated coronary sinus on echocardiography should raise the suspicion of PLSVC. The diagnosis should be confirmed by saline contrast echocardiography. Condition is usually asymptomatic. Here we present a rare case of persistent left superior vena cava presented in OPD with dyspnoea & palpitations.

  14. Transcutaneous electrical nerve stimulation reduces exercise-induced perceived pain and improves endurance exercise performance.

    Science.gov (United States)

    Astokorki, Ali H Y; Mauger, Alexis R

    2017-03-01

    Muscle pain is a natural consequence of intense and prolonged exercise and has been suggested to be a limiter of performance. Transcutaneous electrical nerve stimulation (TENS) and interferential current (IFC) have been shown to reduce both chronic and acute pain in a variety of conditions. This study sought to ascertain whether TENS and IFC could reduce exercise-induced pain (EIP) and whether this would affect exercise performance. It was hypothesised that TENS and IFC would reduce EIP and result in an improved exercise performance. In two parts, 18 (Part I) and 22 (Part II) healthy male and female participants completed an isometric contraction of the dominant bicep until exhaustion (Part I) and a 16.1 km cycling time trial as quickly as they could (Part II) whilst receiving TENS, IFC, and a SHAM placebo in a repeated measures, randomised cross-over, and placebo-controlled design. Perceived EIP was recorded in both tasks using a validated subjective scale. In Part I, TENS significantly reduced perceived EIP (mean reduction of 12%) during the isometric contraction (P = 0.006) and significantly improved participants' time to exhaustion by a mean of 38% (P = 0.02). In Part II, TENS significantly improved (P = 0.003) participants' time trial completion time (~2% improvement) through an increased mean power output. These findings demonstrate that TENS can attenuate perceived EIP in a healthy population and that doing so significantly improves endurance performance in both submaximal isometric single limb exercise and whole-body dynamic exercise.

  15. Electrical Double-Layer Capacitors in Hybrid Topologies —Assessment and Evaluation of Their Performance

    Directory of Open Access Journals (Sweden)

    Joeri Van Mierlo

    2012-11-01

    Full Text Available PHEVs and BEVs make use of battery cells optimized for high energy rather than for high power. This means that the power abilities of these batteries are limited. In order to enhance their performance, a hybrid Rechargeable Energy Storage System (RESS architecture can be used combining batteries with electrical-double layer capacitors (EDLCs. Such a hybridized architecture can be accomplished using passive or active systems. In this paper, the characteristics of these topologies have been analyzed and compared based on a newly developed hybridization simulation tool for association of lithium-ion batteries and EDLCs. The analysis shows that the beneficial impact of the EDLCs brings about enhanced battery performances in terms of energy efficiency and voltage drops, rather than extension of vehicle range. These issues have been particularly studied for the passive and active hybrid topologies. The classical passive and active topologies being expensive and less beneficial in term of cost, volume and weight, a new hybrid configuration based on the parallel combination of lithium-ion and EDLCs on cell level has been proposed in this article. This topology allows reducing cost, volume, and weight and system complexity in a significant way. Furthermore, a number of experimental setups have illustrated the power of the novel topology in terms of battery capacity increase and power capabilities during charging and discharging. Finally, a unique cycle life test campaign demonstrated that the lifetime of highly optimized lithium-ion batteries can be extended up to 30%–40%.

  16. Effects of Dual-Channel Functional Electrical Stimulation on Gait Performance in Patients with Hemiparesis

    Directory of Open Access Journals (Sweden)

    Shmuel Springer

    2012-01-01

    Full Text Available The study objective was to assess the effect of functional electrical stimulation (FES applied to the peroneal nerve and thigh muscles on gait performance in subjects with hemiparesis. Participants were 45 subjects (age 57.8 ± 14.8 years with hemiparesis (5.37 ± 5.43 years since diagnosis demonstrating a foot-drop and impaired knee control. Thigh stimulation was applied either to the quadriceps or hamstrings muscles, depending on the dysfunction most affecting gait. Gait was assessed during a two-minute walk test with/without stimulation and with peroneal stimulation alone. A second assessment was conducted after six weeks of daily use. The addition of thigh muscles stimulation to peroneal stimulation significantly enhanced gait velocity measures at the initial and second evaluation. Gait symmetry was enhanced by the dual-channel stimulation only at the initial evaluation, and single-limb stance percentage only at the second assessment. For example, after six weeks, the two-minute gait speed with peroneal stimulation and with the dual channel was 0.66 ± 0.30 m/sec and 0.70 ± 0.31 m/sec, respectively (. In conclusion, dual-channel FES may enhance gait performance in subjects with hemiparesis more than peroneal FES alone.

  17. Effect of extreme temperatures on battery charging and performance of electric vehicles

    Science.gov (United States)

    Lindgren, Juuso; Lund, Peter D.

    2016-10-01

    Extreme temperatures pose several limitations to electric vehicle (EV) performance and charging. To investigate these effects, we combine a hybrid artificial neural network-empirical Li-ion battery model with a lumped capacitance EV thermal model to study how temperature will affect the performance of an EV fleet. We find that at -10 °C, the self-weighted mean battery charging power (SWMCP) decreases by 15% compared to standard 20 °C temperature. Active battery thermal management (BTM) during parking can improve SWMCP for individual vehicles, especially if vehicles are charged both at home and at workplace; the median SWMCP is increased by over 30%. Efficiency (km/kWh) of the vehicle fleet is maximized when ambient temperature is close to 20 °C. At low (-10 °C) and high (+40 °C) ambient temperatures, cabin preconditioning and BTM during parking can improve the median efficiency by 8% and 9%, respectively. At -10 °C, preconditioning and BTM during parking can also improve the fleet SOC by 3-6%-units, but this also introduces a "base" load of around 140 W per vehicle. Finally, we observe that the utility of the fleet can be increased by 5%-units by adding 3.6 kW chargers to workplaces, but further improved charging infrastructure would bring little additional benefit.

  18. Performance Characteristics of PTC Elements for an Electric Vehicle Heating System

    Directory of Open Access Journals (Sweden)

    Yoon Hyuk Shin

    2016-10-01

    Full Text Available A high-voltage positive temperature coefficient (PTC heater has a simple structure and a swift response. Therefore, for cabin heating in electric vehicles (EVs, such heaters are used either on their own or with a heat pump system. In this study, the sintering process in the manufacturing of PTC elements for an EV heating system was improved to enhance surface uniformity. The electrode production process entailing thin-film sputtering deposition was applied to ensure the high heating performance of PTC elements and reduce the electrode thickness. The allowable voltage and surface heat temperature of the high-voltage PTC elements with thin-film electrodes were 800 V and 172 °C, respectively. The electrode layer thickness was uniform at approximately 3.8 μm or less, approximately 69% less electrode materials were required compared to that before process improvement. Furthermore, a heater for the EV heating system was manufactured using the developed high-voltage PTC elements to verify performance and reliability.

  19. Influence of Sn on Microstructure and Performance of Electric Vacuum Ag-Cu Filler Metal

    Directory of Open Access Journals (Sweden)

    SHI Lei

    2016-10-01

    Full Text Available Influence of Sn on microstructure, melting characteristic and brazing performance of electric vacuum Ag-Cu filler metal was studied by using scanning electronic microscope (SEM with energy disperse spectroscopy (EDS, differential scanning calorimetry (DSC and contrast tests. The results show that, while the addition of Sn is 4% (mass fraction,the same below, there is no brittle β-Cu phase in Ag60Cu filler metal,the effect on the processing performance is not obvious; with the increase of Sn content, the liquidus temperature of Ag60Cu filler metal decreases gradually, but the solidus temperature drops drastically,resulting in wider melting temperature range, and worse gap filling ability of filler metal. The Ag60Cu filler metal with Sn content of 4% has good spreading and metallurgical bonding abilities on copper plates, which are closer to that of BAg72Cu filler metal, and it can be processed into flake filler metal to replace the BAg72Cu flake filler metal to be used.

  20. The effect of the optical system on the electrical performance of III–V concentrator triple junction solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, R.D., E-mail: S206029578@nmmu.ac.za; Dyk, E.E. van; Vorster, F.J.

    2016-01-01

    High Concentrated Photovoltaic (H-CPV) technologies utilize relatively inexpensive reflective and refractive optical components for concentration to achieve high energy yield. The electrical performance of H-CPV systems is, however, dependent on the properties and configuration of the optical components. The focus of this paper is to summarize the effect of the properties of the optical system on the electrical performance of a Concentrator Triple Junction (CTJ) InGaP/InGaAs/Ge cell. Utilizing carefully designed experiments that include spectral measurements and intensity profiles in the optical plane of the CTJ cell, the influence of photon absorption, Fresnel lens properties and chromatic aberration created by the optical system on the electrical performance of a CTJ cell is shown. From the results obtained, it is concluded that good characterization and understanding of the optical system’s properties may add to improved design of future multi-junction devices.

  1. Electrothermal Annealing (ETA) Method to Enhance the Electrical Performance of Amorphous-Oxide-Semiconductor (AOS) Thin-Film Transistors (TFTs).

    Science.gov (United States)

    Kim, Choong-Ki; Kim, Eungtaek; Lee, Myung Keun; Park, Jun-Young; Seol, Myeong-Lok; Bae, Hagyoul; Bang, Tewook; Jeon, Seung-Bae; Jun, Sungwoo; Park, Sang-Hee K; Choi, Kyung Cheol; Choi, Yang-Kyu

    2016-09-14

    An electro-thermal annealing (ETA) method, which uses an electrical pulse of less than 100 ns, was developed to improve the electrical performance of array-level amorphous-oxide-semiconductor (AOS) thin-film transistors (TFTs). The practicality of the ETA method was experimentally demonstrated with transparent amorphous In-Ga-Zn-O (a-IGZO) TFTs. The overall electrical performance metrics were boosted by the proposed method: up to 205% for the trans-conductance (gm), 158% for the linear current (Ilinear), and 206% for the subthreshold swing (SS). The performance enhancement were interpreted by X-ray photoelectron microscopy (XPS), showing a reduction of oxygen vacancies in a-IGZO after the ETA. Furthermore, by virtue of the extremely short operation time (80 ns) of ETA, which neither provokes a delay of the mandatory TFTs operation such as addressing operation for the display refresh nor demands extra physical treatment, the semipermanent use of displays can be realized.

  2. Characterization of few-layer 1T-MoSe{sub 2} and its superior performance in the visible-light induced hydrogen evolution reaction

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Uttam; Naidu, B. S.; Maitra, Urmimala; Rao, C. N. R., E-mail: cnrrao@jncasr.ac.in [Chemistry and Physics Materials Unit, New Chemistry Unit and International Centre for Materials Science, Sheik Saqr Laboratory, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P. O., Bangalore 560064 (India); Singh, Anjali; Shirodkar, Sharmila N.; Waghmare, Umesh V. [Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P. O., Bangalore 560064 (India)

    2014-09-01

    Based on earlier results on the photocatalytic properties of MoS{sub 2}, the 1T form of MoSe{sub 2}, prepared by lithium intercalation and exfoliation of bulk MoSe{sub 2}, has been employed for the visible-light induced generation of hydrogen. 1T-MoSe{sub 2} is found to be superior to both 2H and 1T MoS{sub 2} as well as 2H-MoSe{sub 2} in producing hydrogen from water, the yield being in the 60–75 mmol h{sup −1} g{sup −1} range with a turn over frequency of 15–19 h{sup −1}. First principles calculations reveal that 1T-MoSe{sub 2} has a lower work function than 2H-MoSe{sub 2} as well as 1T and 2H-MoS{sub 2}, making it easier to transfer an electron from 1T-MoSe{sub 2} for the production of H{sub 2}.

  3. Characterization of few-layer 1T-MoSe2 and its superior performance in the visible-light induced hydrogen evolution reaction

    Directory of Open Access Journals (Sweden)

    Uttam Gupta

    2014-09-01

    Full Text Available Based on earlier results on the photocatalytic properties of MoS2, the 1T form of MoSe2, prepared by lithium intercalation and exfoliation of bulk MoSe2, has been employed for the visible-light induced generation of hydrogen. 1T-MoSe2 is found to be superior to both 2H and 1T MoS2 as well as 2H-MoSe2 in producing hydrogen from water, the yield being in the 60–75 mmol h−1 g−1 range with a turn over frequency of 15–19 h−1. First principles calculations reveal that 1T-MoSe2 has a lower work function than 2H-MoSe2 as well as 1T and 2H-MoS2, making it easier to transfer an electron from 1T-MoSe2 for the production of H2.

  4. Analysis Of The Performance Of An Optimization Model For Time-Shiftable Electrical Load Scheduling Under Uncertainty

    Science.gov (United States)

    2016-12-01

    NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS ANALYSIS OF THE PERFORMANCE OF AN OPTIMIZATION MODEL FOR TIME-SHIFTABLE ELECTRICAL LOAD...REPORT TYPE AND DATES COVERED Master’s Thesis 01-04-2016 to 09-23-2016 4. TITLE AND SUBTITLE ANALYSIS OF THE PERFORMANCE OF AN OPTIMIZATIONMODEL FOR...INTENTIONALLY LEFT BLANK ii Approved for public release. Distribution is unlimited. ANALYSIS OF THE PERFORMANCE OF AN OPTIMIZATION MODEL FOR TIME-SHIFTABLE

  5. Electric Vehicle Performance at McMurdo Station (Antarctica) and Comparison with McMurdo Station Conventional Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Sears, T.; Lammert, M.; Colby, K.; Walter, R.

    2014-09-01

    This report examines the performance of two electric vehicles (EVs) at McMurdo, Antarctica (McMurdo). The study examined the performance of two e-ride Industries EVs initially delivered to McMurdo on February 16, 2011, and compared their performance and fuel use with that of conventional vehicles that have a duty cycle similar to that of the EVs used at McMurdo.

  6. Modelling and Assessing Energy Performance of an Urban Transport System with Electric Drives

    Directory of Open Access Journals (Sweden)

    Ioan Felea

    2013-10-01

    Full Text Available Energy conservation is one of the key priorities of sustainable development strategy. Transport systems are responsible for about one third of energy consumption. As result, the identification of solutions to reduce energy consumption in these systems is essential for the implementation of the sustainable development strategies. The present work is dedicated to identifying the possibilities for a reduction in the consumption of electric energy in electric urban public transport systems, using the audit of their electricity system. After justifying the importance of these concerns, a mathematical model of the electrical energy balance of the electric urban public transport system and its components is presented. The analysis is applied to determine the losses in the system components and useful energy, based on the evaluation and energy consumption measurements. The measurements to reduce energy losses are identified and characterized under technical and economic aspect, optimal electrical energy balances being done on this basis.

  7. Superior electrochemical properties of manganese dioxide/reduced graphene oxide nanocomposites as anode materials for high-performance lithium ion batteries

    Science.gov (United States)

    Lee, Suk-Woo; Lee, Chang-Wook; Yoon, Seung-Beom; Kim, Myeong-Seong; Jeong, Jun Hui; Nam, Kyung-Wan; Roh, Kwang Chul; Kim, Kwang-Bum

    2016-04-01

    MnO2/reduced graphene oxide (rGO) nanocomposites were synthesized via a simple solution method at room temperature for use in Li-ion batteries. Owing to the mesoporous features as well as the high electrical conductivity of rGO, the overall electronic and ionic conductivities of the nanocomposite were increased, resulting in improved electrochemical properties in terms of specific capacity, rate capability, and cyclability. In particular, as-prepared nanocomposites showed 222 and 115 mAh g-1 at a current density of as high as 5 and 10 A g-1, and the specific capacitance was well maintained after 400 cycles. In addition, MnO2, via composite formation with rGO, permitted the additional conversion reaction between MnO and Mn3O4, resulting in the reduction of the initial irreversible capacity despite the high first discharge capacity caused by the large specific surface area.

  8. Trajetória escolar do surdo no ensino superior: condições e possibilidades School performance of the deaf in higher education: conditions and possibilities

    Directory of Open Access Journals (Sweden)

    José Ildon Gonçalves da Cruz

    2009-04-01

    Full Text Available Devido ao número relativamente pequeno de surdos que frequentam o ensino superior, este estudo objetivou conhecer as suas condições nesse nível de ensino. Participaram da pesquisa sete surdos universitários, na faixa etária entre 22 e 39 anos. Os dados foram obtidos por meio de entrevistas individuais sucessivas, presenciais ou à distância, via internet, empregando o português falado, escrito ou a língua de sinais, com a mediação de intérprete. Realizaram-se dez entrevistas presenciais, gravadas e transcritas, e onze à distância, mediante e-mail e Messenger®. Os relatos foram analisados sob o ponto de vista sócio-antropológico, que entende os surdos como diferentes, linguística e culturalmente, pertencentes aos grupos minoritários e que frequentam, na maioria das vezes, uma escola organizada para ouvintes e padronizada. Os resultados apontam que as condições dos surdos no ensino superior são de dificuldades, de impedimentos, de abandono e de rejeição. Os surdos são obrigados a se responsabilizarem por sua aprendizagem, priorizando o trabalho extra classe para recuperação de notas. A escola se organiza de acordo com interesses e necessidades dos ouvintes, isto é: não há uma língua compartilhada com os alunos surdos, não há intérprete português-Libras, não há contexto bicultural, não há interlocução na escola. Concluiu-se que os surdos são capazes, produtivos, solidários e interessados em avançar no seu processo de escolarização, apesar dos empecilhos encontrados no interior do espaço escolar.Due to the relatively small number of deaf students enrolled in higher education, this study aimed to look at learning conditions at that educational level. Seven deaf college students, aged 22-39, participated in the research study. Data was collected through successive individual interviews, in person or by internet, using Portuguese language in spoken or written form or through the manual alphabet with the

  9. Enhancing performance of a motor imagery based brain–computer interface by incorporating electrical stimulation-induced SSSEP

    Science.gov (United States)

    Yi, Weibo; Qiu, Shuang; Wang, Kun; Qi, Hongzhi; Zhao, Xin; He, Feng; Zhou, Peng; Yang, Jiajia; Ming, Dong

    2017-04-01

    Objective. We proposed a novel simultaneous hybrid brain–computer interface (BCI) by incorporating electrical stimulation into a motor imagery (MI) based BCI system. The goal of this study was to enhance the overall performance of an MI-based BCI. In addition, the brain oscillatory pattern in the hybrid task was also investigated. Approach. 64-channel electroencephalographic (EEG) data were recorded during MI, selective attention (SA) and hybrid tasks in fourteen healthy subjects. In the hybrid task, subjects performed MI with electrical stimulation which was applied to bilateral median nerve on wrists simultaneously. Main results. The hybrid task clearly presented additional steady-state somatosensory evoked potential (SSSEP) induced by electrical stimulation with MI-induced event-related desynchronization (ERD). By combining ERD and SSSEP features, the performance in the hybrid task was significantly better than in both MI and SA tasks, achieving a ~14% improvement in total relative to the MI task alone and reaching ~89% in mean classification accuracy. On the contrary, there was no significant enhancement obtained in performance while separate ERD feature was utilized in the hybrid task. In terms of the hybrid task, the performance using combined feature was significantly better than using separate ERD or SSSEP feature. Significance. The results in this work validate the feasibility of our proposed approach to form a novel MI-SSSEP hybrid BCI outperforming a conventional MI-based BCI through combing MI with electrical stimulation.

  10. INFLUENCE OF ELECTRICAL AND STRUCTURAL PARAMETERS ON THE PERFORMANCE OF THE SPACERS IN HOPFED

    Institute of Scientific and Technical Information of China (English)

    Zhong Xuefei; Wilbert van der Poel; Daniel den Engelsen; Yin Hanchun

    2006-01-01

    The HOPping Field Emission Display (HOPFED) is a new architecture for field emission displays.The main difference between a conventional Field Emission Display (FED) device and a HOPFED lies in the spacer structure. In a HOPFED, two dielectric plates, named hop and flu spacer, are sandwiched between the emitter and the front plate. The objective of this spacer structure is to improve the performance of a FED substantially with notable contrast, color purity and luminance uniformity. In order to optimize the structure of the device and to make the electron spot on the screen match the requirement of the phosphor dot dimension,the influence of electrical and structural parameters of the device on the electron spot profile was studied by numerical simulation in this paper. Monte Carlo method was employed to calculate the potential distribution inside hop and flu spacers due to secondary electrons mechanism plays an important role in HOPFED. The results indicated that the potential distribution in the spacers and spot profile depended strongly on the hop voltage, anode voltage and spacer's layout. This study may provide a useful theoretical support for optimizing the structure in HOPFED.

  11. Fuel reforming and electrical performance studies in intermediate temperature ceria - gadolinia-based SOFCs

    Energy Technology Data Exchange (ETDEWEB)

    Livermore, S.J.A. [CERAM Research, Stoke-on-Trent (United Kingdom); Birchall Centre for Inorganic Chemistry and Materials Science, Department of Chemistry, Keele Univ. (United Kingdom); Cotton, J.W. [CERAM Research, Stoke-on-Trent (United Kingdom); Ormerod, R.M. [Birchall Centre for Inorganic Chemistry and Materials Science, Department of Chemistry, Keele Univ. (United Kingdom)

    2000-03-01

    The methane reforming and carbon deposition characteristics of two nickel/ceria-gadolinia cermet anodes have been studied over the temperature range 550-700 C, for use in intermediate temperature ceria-gadolinia (CGO)-based solid oxide fuel cells (SOFCs), using conventional catalytic methods and temperature-programmed spectroscopy. The electrical performance and durability of planar CGO-based SOFCs with a 280-{mu}m-thick CGO electrolyte, screen printed cathode and different screen printed nickel/CGO cermet anodes have been studied over the temperature range 500-650 C. Temperature-programmed reduction has been used to study the reduction characteristics of the anodes, and indicates the presence of 'bulk' NiO particles and smaller NiO particles in intimate contact with the ceria. Both anodes show good activity towards methane steam reforming with methane activation occurring at temperatures as low as 210 C; steady-state steam reforming of methane was observed using a methane-rich mixture at 650 C, with 20% methane conversion. Post-reaction temperature-programmed oxidation has been used to determine the amount of carbon deposited during reforming and the strength of its interaction with the anode. (orig.)

  12. Effects of Dual-Channel Functional Electrical Stimulation on Gait Performance in Patients with Hemiparesis

    Science.gov (United States)

    Springer, Shmuel; Vatine, Jean-Jacques; Lipson, Ronit; Wolf, Alon; Laufer, Yocheved

    2012-01-01

    The study objective was to assess the effect of functional electrical stimulation (FES) applied to the peroneal nerve and thigh muscles on gait performance in subjects with hemiparesis. Participants were 45 subjects (age 57.8 ± 14.8 years) with hemiparesis (5.37 ± 5.43 years since diagnosis) demonstrating a foot-drop and impaired knee control. Thigh stimulation was applied either to the quadriceps or hamstrings muscles, depending on the dysfunction most affecting gait. Gait was assessed during a two-minute walk test with/without stimulation and with peroneal stimulation alone. A second assessment was conducted after six weeks of daily use. The addition of thigh muscles stimulation to peroneal stimulation significantly enhanced gait velocity measures at the initial and second evaluation. Gait symmetry was enhanced by the dual-channel stimulation only at the initial evaluation, and single-limb stance percentage only at the second assessment. For example, after six weeks, the two-minute gait speed with peroneal stimulation and with the dual channel was 0.66 ± 0.30 m/sec and 0.70 ± 0.31 m/sec, respectively (P hemiparesis more than peroneal FES alone. PMID:23097635

  13. Performance Evaluation and Design Considerations of Electrically Activated Drain Extension Tunneling GNRFET: A Quantum Simulation Study

    Science.gov (United States)

    Ghoreishi, Seyed Saleh; Yousefi, Reza; Taghavi, Neda

    2017-07-01

    In this paper, a tunneling graphene nanoribbon field effect transistor with electrically activated drain extension, namely, EA-T-GNRFET, is proposed. The proposed structure includes a side gate at the drain side with a constant voltage and length of 0.4 V and 15 nm, respectively. Simulations are performed based on the non-equilibrium Green's function method coupled with the Poisson equation in the mode space representation. This side gate creates an additional step in potential profile at the drain side, which increases and decreases the width of tunneling barrier and leakage current, respectively. Furthermore, the proposed structure has lower drain induced barrier thinning, lower sub-threshold swing (SS) and higher I ON/I OFF ratio than the conventional structure. Also, other characteristics of the device such as switching delay ( τ ), power delay product (PDP) and unity-gain frequency (f t) are improved in the proposed device. These advantages make EA-T-GNRFET more suitable for digital and analog applications.

  14. Selection of the battery pack parameters for an electric vehicle based on performance requirements

    Science.gov (United States)

    Koniak, M.; Czerepicki, A.

    2017-06-01

    Each type of vehicle has specific power requirements. Some require a rapid charging, other make long distances between charges, but a common feature is the longest battery life time. Additionally, the battery is influenced by factors such as temperature, depth of discharge and the operation current. The article contain the parameters of chemical cells that should be taken into account during the design of the battery for a specific application. This is particularly important because the batteries are not properly matched and can wear prematurely and cause an additional costs. The method of selecting the correct cell type should take previously discussed features and operating characteristics of the vehicle into account. The authors present methods of obtaining such characteristics along with their assessment and examples. Also there has been described an example of the battery parameters selection based on design assumptions of the vehicle and the expected performance characteristics. Selecting proper battery operating parameters is important due to its impact on the economic result of investments in electric vehicles. For example, for some Li-Ion technologies, the earlier worn out of batteries in a fleet of cruise boats or buses having estimated lifetime of 10 years is not acceptable, because this will cause substantial financial losses for the owner of the rolling stock. The presented method of choosing the right cell technology in the selected application, can be the basis for making the decision on future battery technical parameters.

  15. The Electrostatic Wind Energy Converter: electrical performance of a high voltage prototype

    NARCIS (Netherlands)

    Djairam, D.

    2008-01-01

    Wind energy is converted to electrical energy by letting the wind move charged particles against the direction of an electric field. The advantage of this type of conversion is that no rotational movement, which occurs in conventional wind turbines, is required. An electrostatic wind energy

  16. Review of in vivo static and ELF electric fields studies performed at Gazi Biophysics Department.

    Science.gov (United States)

    Seyhan, Nesrin; Güler, Göknur

    2006-01-01

    In vivo effects of Static Electric and ELF Magnetic and Electric fields have been carried out for more than 20 years in the Bioelectromagnetic Laboratory at the Biophysics Department of the Medical Faculty of Gazi University. In this article, the results of in vivo ELF Electric field studies are presented as a review. Static and 50 Hz ELF (Extremely Low Frequency) Electric (E) fields effects on free radical synthesis, antioxidant enzyme level, and collagen synthesis were analyzed on tissues of guinea pigs, such as brain, liver, lung, kidney, spleen, testis, and plasma. Animals were exposed to static and ELF electric fields with intensities ranging from 0.3 kV/m to 1.9 kV/m in vertical and horizontal directions. Exposure periods were 1, 3, 5, 7, and 10 days. Electric fields were generated from a specially designed parallel plate capacitor system. The results indicate that the effects of electric fields on the tissues studied depend significantly on the type and magnitude of electric field and exposure period.

  17. OVERALL PERFORMANCE OF THE ELECTRIC ARC MELTING FURNACE DEPENDING ON QUALITY OF FURNACE CHARGE

    Directory of Open Access Journals (Sweden)

    A. B. Steblov

    2016-01-01

    Full Text Available The quality of furnace charge in an electric arc melting furnace to a large extend determines the efficiency of melting. With a tendency of increase of light scrap with a high content of non-iron impurities scrap fine crushing can increase the metallurgical value of scrap and improve technical and economic parameters of electric arc furnace operation.

  18. Performance Evaluation of an In-Wheel Motor Cooling System in an Electric Vehicle/Hybrid Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Dong Hyun Lim

    2014-02-01

    Full Text Available High power and miniaturization of motors in an in-wheel drive system, which is installed inside the wheels of a vehicle, are required for directly driving the wheels. In addition, an efficient cooling system is required to ensure high driving performance and durability. This study experimentally evaluated the heat dissipation performance of a 35-kW-class large-capacity in-wheel motor equipped with an internal-circulation-type oil-cooling system that exhibits high cooling performance and can be easily miniaturized to this motor. Temperatures of the coil and stator core of cooling systems with and without a radiator were measured in real time under in-wheel motor driving conditions. It was found that operating the cooling system at a continuous-rating maximum speed without the radiator was difficult. We confirmed that under continuous-rating base speed and continuous-rating maximum speed driving conditions, the cooling system with the radiator showed thermally stable operation. Furthermore, under maximum-rating base speed and maximum-rating maximum speed driving conditions, the cooling system with the radiator provided additional driving times of approximately 22 s and 2 s, respectively.

  19. Air Superiority Fighter Characteristics.

    Science.gov (United States)

    1998-06-05

    many a dispute could have been deflated into a single paragraph if the disputants had just dared to define their terms.7 Aristotle ...meaningful. This section will expand on some key ideology concepts. The phrase "air superiority fighter" may bring to mind visions of fighter... biographies are useful in garnering airpower advocate theories as well as identifying key characteristics. Air campaign results, starting with World

  20. Implications of driving patterns on well-to-wheel performance of plug-in hybrid electric vehicles.

    Science.gov (United States)

    Raykin, Leon; MacLean, Heather L; Roorda, Matthew J

    2012-06-05

    This study examines how driving patterns (distance and conditions) and the electricity generation supply interact to impact well-to-wheel (WTW) energy use and greenhouse gas (GHG) emissions of plug-in hybrid electric vehicles (PHEVs). The WTW performance of a PHEV is compared with that of a similar (nonplug-in) gasoline hybrid electric vehicle and internal combustion engine vehicle (ICEV). Driving PHEVs for short distances between recharging generally results in lower WTW total and fossil energy use and GHG emissions per kilometer compared to driving long distances, but the extent of the reductions depends on the electricity supply. For example, the shortest driving pattern in this study with hydroelectricity uses 81% less fossil energy than the longest driving pattern. However, the shortest driving pattern with coal-based electricity uses only 28% less fossil energy. Similar trends are observed in reductions relative to the nonplug-in vehicles. Irrespective of the electricity supply, PHEVs result in greater reductions in WTW energy use and GHG emissions relative to ICEVs for city than highway driving conditions. PHEVs charging from coal facilities only reduce WTW energy use and GHG emissions relative to ICEVs for certain favorable driving conditions. The study results have implications for environmentally beneficial PHEV adoption and usage patterns.

  1. [Influence of buffer solutions on the performance of microbial fuel cell electricity generation].

    Science.gov (United States)

    Qiang, Lin; Yuan, Lin-jiang; Ding, Qing

    2011-05-01

    Microbial fuel cell (MFC) is a potential green technology due to its application in wastewater treatment and renewable energy generation. Phosphate buffer solution (PBS) has been commonly used in MFC studies to maintain a suitable pH for electricity generating bacteria and/or to increase the solution conductivity. However, it has some drawbacks using PBS in MFC: One is that the addition of a high concentration of phosphate buffer in MFCs is expensive, especially for the application in wastewater treatment; the other is that phosphates can contribute to the eutrophication conditions of water bodies if the effluents are discharged without the removal of phosphates. By adding PBS buffer as the comparison, the study investigated the effect of borax buffer and in the absence of buffer on the performance of electrical power, coulomb efficiency and effluent pH. 200 mmol/L PBS was the best, conductivity was 1.973 mS/cm,the maximum power density was 36.4 mW/m2 and the maximum coulomb efficiency was 2.92%, effluent pH was almost at (7.00 +/- 0.05). 100 mmol/L borax buffer solution, conductivity was 1.553 mS/cm; the maximum power density was 26.2 mW/m2 coulomb efficiency of 6.26%, which was 2.14 times to PBS and greatly increased the electron recovery efficiency with the effluent pH was (7.35 +/- 0.05). While free buffer solution conductivity was 0.314 mS/cm, maximum power density was 27.64 mW/m2; coulomb efficiency was 2.82% and the effluent pH of approximately 7.43. The electrolyte which in absence of buffer solution conductivity was 1/6 of adding PBS buffer, 1/5 of borax buffer, while its power density lower 8.76 mW/mr2 than adding PBS and higher 1.24 mW/m2 than borax buffer. The results showed that adding the suitable concentration of borax buffer may improve the electron recovery efficiency and under batch conditions, MFC run successfully without adding buffer solution to MFC.

  2. Leiomyosarcoma of the superior vena cava.

    Science.gov (United States)

    de Chaumont, Arthus; Pierret, Charles; de Kerangal, Xavier; Le Moulec, Sylvestre; Laborde, François

    2014-08-01

    Leiomyosarcoma of the superior vena cava is a very rare tumor and only a few cases have been reported, with various techniques of vascular reconstruction. We describe a new case of leiomyosarcoma of the superior vena cava in a 61-year-old woman with extension to the brachiocephalic arterial trunk. Resection and vascular reconstruction were performed using, respectively, polytetrafluoroethylene and polyethylene terephtalate vascular grafts.

  3. Porous nitrogen-doped carbon derived from silk fibroin protein encapsulating sulfur as a superior cathode material for high-performance lithium-sulfur batteries.

    Science.gov (United States)

    Zhang, Jiawei; Cai, Yurong; Zhong, Qiwei; Lai, Dongzhi; Yao, Juming

    2015-11-14

    The features of a carbon substrate are crucial for the electrochemical performance of lithium-sulfur (Li-S) batteries. Nitrogen doping of carbon materials is assumed to play an important role in sulfur immobilisation. In this study, natural silk fibroin protein is used as a precursor of nitrogen-rich carbon to fabricate a novel, porous, nitrogen-doped carbon material through facile carbonisation and activation. Porous carbon, with a reversible capacity of 815 mA h g(-1) at 0.2 C after 60 cycles, serves as the cathode material in Li-S batteries. Porous carbon retains a reversible capacity of 567 mA h g(-1), which corresponds to a capacity retention of 98% at 1 C after 200 cycles. The promising electrochemical performance of porous carbon is attributed to its mesoporous structure, high specific surface area and nitrogen doping into the carbon skeleton. This study provides a general strategy to synthesise nitrogen-doped carbons with a high specific surface area, which is crucial to improve the energy density and electrochemical performance of Li-S batteries.

  4. Whisker-related afferents in superior colliculus.

    Science.gov (United States)

    Castro-Alamancos, Manuel A; Favero, Morgana

    2016-05-01

    Rodents use their whiskers to explore the environment, and the superior colliculus is part of the neural circuits that process this sensorimotor information. Cells in the intermediate layers of the superior colliculus integrate trigeminotectal afferents from trigeminal complex and corticotectal afferents from barrel cortex. Using histological methods in mice, we found that trigeminotectal and corticotectal synapses overlap somewhat as they innervate the lower and upper portions of the intermediate granular layer, respectively. Using electrophysiological recordings and optogenetics in anesthetized mice in vivo, we showed that, similar to rats, whisker deflections produce two successive responses that are driven by trigeminotectal and corticotectal afferents. We then employed in vivo and slice experiments to characterize the response properties of these afferents. In vivo, corticotectal responses triggered by electrical stimulation of the barrel cortex evoke activity in the superior colliculus that increases with stimulus intensity and depresses with increasing frequency. In slices from adult mice, optogenetic activation of channelrhodopsin-expressing trigeminotectal and corticotectal fibers revealed that cells in the intermediate layers receive more efficacious trigeminotectal, than corticotectal, synaptic inputs. Moreover, the efficacy of trigeminotectal inputs depresses more strongly with increasing frequency than that of corticotectal inputs. The intermediate layers of superior colliculus appear to be tuned to process strong but infrequent trigeminal inputs and weak but more persistent cortical inputs, which explains features of sensory responsiveness, such as the robust rapid sensory adaptation of whisker responses in the superior colliculus. Copyright © 2016 the American Physiological Society.

  5. Improvement in the electrical performance and bias-stress stability of dual-active-layered silicon zinc oxide/zinc oxide thin-film transistor

    Science.gov (United States)

    Liu, Yu-Rong; Zhao, Gao-Wei; Lai, Pai-To; Yao, Ruo-He

    2016-08-01

    Si-doped zinc oxide (SZO) thin films are deposited by using a co-sputtering method, and used as the channel active layers of ZnO-based TFTs with single and dual active layer structures. The effects of silicon content on the optical transmittance of the SZO thin film and electrical properties of the SZO TFT are investigated. Moreover, the electrical performances and bias-stress stabilities of the single- and dual-active-layer TFTs are investigated and compared to reveal the effects of the Si doping and dual-active-layer structure. The average transmittances of all the SZO films are about 90% in the visible light region of 400 nm-800 nm, and the optical band gap of the SZO film gradually increases with increasing Si content. The Si-doping can effectively suppress the grain growth of ZnO, revealed by atomic force microscope analysis. Compared with that of the undoped ZnO TFT, the off-state current of the SZO TFT is reduced by more than two orders of magnitude and it is 1.5 × 10-12 A, and thus the on/off current ratio is increased by more than two orders of magnitude. In summary, the SZO/ZnO TFT with dual-active-layer structure exhibits a high on/off current ratio of 4.0 × 106 and superior stability under gate-bias and drain-bias stress. Projected supported by the National Natural Science Foundation of China (Grant Nos. 61076113 and 61274085), the Natural Science Foundation of Guangdong Province (Grant No. 2016A030313474), and the University Development Fund (Nanotechnology Research Institute, Grant No. 00600009) of the University of Hong Kong, China.

  6. A Combined Optical, Thermal and Electrical Performance Study of a V-Trough PV System—Experimental and Analytical Investigations

    Directory of Open Access Journals (Sweden)

    Haitham M. Bahaidarah

    2015-04-01

    Full Text Available The objective of this study was to achieve higher efficiency of a PV system while reducing of the cost of energy generation. Concentration photovoltaics was employed in the present case as it uses low cost reflectors to enhance the efficiency of the PV system and simultaneously reduces the cost of electricity generation. For this purpose a V-trough integrated with the PV system was employed for low concentration photovoltaic (LCPV. Since the electrical output of the concentrating PV system is significantly affected by the temperature of the PV cells, the motivation of the research also included studying the ability to actively cool PV cells to achieve the maximum benefit. The optical, thermal and electrical performance of the V-trough PV system was theoretically modeled and validated with experimental results. Optical modeling of V-trough was carried out to estimate the amount of enhanced absorbed radiation. Due to increase in the absorbed radiation the module temperature was also increased which was predicted by thermal model. Active cooling techniques were studied and the effect of cooling was analyzed on the performance of V-trough PV system. With absorbed radiation and module temperature as input parameters, electrical modeling was carried out and the maximum power was estimated. For the V-trough PV system, experiments were performed for validating the numerical models and very good agreement was found between the two.

  7. High performance thin film transistor (flex-TFT) with textured nanostructure ZnO film channel fabricated by exploiting electric double layer gate insulator

    Science.gov (United States)

    Ghimire, Rishi Ram; Raychaudhuri, A. K.

    2017-01-01

    We report a flexible thin film transistor (flex-TFT) fabricated on a commonly available polyimide (Kapton®) tape with a channel of highly textured nanocrystalline ZnO film grown by pulsed laser deposition. The flex-TFT with an electric double layer (EDL) gate insulator shows a low threshold for operation (Vth ≤ 1 V), an ON/OFF ratio reaching ≈107 and a subthreshold swing ≈75 mV/dec. The superior performance is enabled by a high saturation mobility (μs ≈ 70 cm2/V s) of the highly textured nanocrystalline channel. The low Vth arises from large charge density (≈1014/cm2) induced into the channel by EDL gate insulator. The large charge density induced by the EDL gate dielectric also enhances the Hall mobility in the film and brings down the sheet resistance by nearly 2 orders, which leads to large ON/OFF ratio. The flex-TFT operation can be sustained with reproducibility when the TFT is bent down to a radius of curvature ≈2 cm.

  8. Contabilidad Financiera Superior

    OpenAIRE

    Ipiñazar Petralanda, Izaskun

    2013-01-01

    Duración (en horas): De 31 a 40 horas. Destinatario: Estudiante y Docente A través de este material se presentan las pautas necesarias para implementar un aprendizaje basado en problemas en la asignatura de Contabilidad Financiera Superior dentro de los temas “Constitución de S.A. y S.R.L.” (Tema 2), “Ampliaciones de Capital” (Tema 3) y “Reducciones de Capital” (Tema 4). En primer lugar se presentan las guías generales de la asignatura, y a continuación, las diferentes activida...

  9. Contabilidad Financiera Superior

    OpenAIRE

    Ipiñazar Petralanda, Izaskun

    2013-01-01

    Duración (en horas): De 31 a 40 horas. Destinatario: Estudiante y Docente A través de este material se presentan las pautas necesarias para implementar un aprendizaje basado en problemas en la asignatura de Contabilidad Financiera Superior dentro de los temas “Constitución de S.A. y S.R.L.” (Tema 2), “Ampliaciones de Capital” (Tema 3) y “Reducciones de Capital” (Tema 4). En primer lugar se presentan las guías generales de la asignatura, y a continuación, las diferentes activida...

  10. A plum-pudding like mesoporous SiO2/flake graphite nanocomposite with superior rate performance for LIB anode materials.

    Science.gov (United States)

    Li, Huan-Huan; Zhang, Lin-Lin; Fan, Chao-Ying; Wang, Kang; Wu, Xing-Long; Sun, Hai-Zhu; Zhang, Jing-Ping

    2015-09-21

    A novel kind of plum-pudding like mesoporous SiO2 nanospheres (MSNs) and flake graphite (FG) nanocomposite (pp-MSNs/FG) was designed and fabricated via a facile and cost-effective hydrothermal method. Transmission electron microscopy (TEM) analysis showed that most of the MSNs were well anchored on FG. This special architecture has multiple advantages, including FG that offers a conductive framework and hinders the volume expansion effect. Moreover, the porous structure of MSNs could provide more available lithium storage sites and extra free space to accommodate the mechanical strain caused by the volume change during the repeated reversible reaction between Li(+) and active materials. Due to the synergetic effects of its unique plum-pudding structure, the obtained pp-MSNs/FG nanocomposite exhibited a decent reversible capacity of 702 mA h g(-1) (based on the weight of MSNs in the electrode material) after 100 cycles with high Coulombic efficiency above 99% under 100 mA g(-1) and a charge capacity of 239.6 mA h g(-1) could be obtained even under 5000 mA g(-1). Their high rate performance is among the best-reported performances of SiO2-based anode materials.

  11. Polyimide-coated carbon electrodes combined with redox mediators for superior Li-O2 cells with excellent cycling performance and decreased overpotential

    Science.gov (United States)

    Yoon, Seon Hye; Park, Yong Joon

    2017-02-01

    We report an air electrode employing polyimide-coated carbon nanotubes (CNTs) combined with a redox mediator for Li-O2 cells with enhanced electrochemical performance. The polyimide coating on the carbon surface suppresses unwanted side reactions, which decreases the amount of accumulated reaction products on the surface of the air electrode during cycling. The redox mediators lower the overpotential of the Li-O2 cells because they can easily transfer electrons from the electrode to the reaction products. The low overpotential can also decrease the side reactions that activate at a high potential range. Specifically, the CsI redox mediator effectively interrupted dendrite growth on the Li anode during cycling due to the shielding effect of its Cs+ ions and acted as a redox mediator due to its I‑ ions. LiNO3 also facilitates the decrease in side reactions and the stabilization of the Li anode. The synergic effect of the polyimide coating and the electrolyte containing the LiNO3/CsI redox mediator leads to a low overpotential and excellent cycling performance (over 250 cycles with a capacity of 1,500 mAh·gelectrode‑1).

  12. Superior performance of metal-organic frameworks over zeolites as solid acid catalysts in the Prins reaction: green synthesis of nopol.

    Science.gov (United States)

    Opanasenko, Maksym; Dhakshinamoorthy, Amarajothi; Hwang, Young Kyu; Chang, Jong-San; Garcia, Hermenegildo; Čejka, Jiří

    2013-05-01

    The catalytic performance of a set of metal-organic frameworks [CuBTC, FeBTC, MIL-100(Fe), MIL-100(Cr), ZIF-8, MIL-53(Al)] was investigated in the Prins condensation of β-pinene with formaldehyde and compared with the catalytic behavior of conventional aluminosilicate zeolites BEA and FAU and titanosilicate zeolite MFI (TS-1). The activity of the investigated metal-organic frameworks (MOFs) increased with the increasing concentration of accessible Lewis acid sites in the order ZIF-8zeolites BEA and FAU, which showed significantly lower selectivity to the target nopol than the MOFs. Its high activity, the preservation of its structure and active sites, and the possibility to use it in at least three catalytic cycles without loss of activity make MIL-100 (Fe) the best performing catalyst of the series for the Prins condensation of β-pinene and paraformaldehyde. Our report exemplifies the advantages of MOFs over zeolites as solid catalysts in liquid-phase reactions for the production of fine chemicals.

  13. Polyimide-coated carbon electrodes combined with redox mediators for superior Li-O2 cells with excellent cycling performance and decreased overpotential

    Science.gov (United States)

    Yoon, Seon Hye; Park, Yong Joon

    2017-01-01

    We report an air electrode employing polyimide-coated carbon nanotubes (CNTs) combined with a redox mediator for Li-O2 cells with enhanced electrochemical performance. The polyimide coating on the carbon surface suppresses unwanted side reactions, which decreases the amount of accumulated reaction products on the surface of the air electrode during cycling. The redox mediators lower the overpotential of the Li-O2 cells because they can easily transfer electrons from the electrode to the reaction products. The low overpotential can also decrease the side reactions that activate at a high potential range. Specifically, the CsI redox mediator effectively interrupted dendrite growth on the Li anode during cycling due to the shielding effect of its Cs+ ions and acted as a redox mediator due to its I− ions. LiNO3 also facilitates the decrease in side reactions and the stabilization of the Li anode. The synergic effect of the polyimide coating and the electrolyte containing the LiNO3/CsI redox mediator leads to a low overpotential and excellent cycling performance (over 250 cycles with a capacity of 1,500 mAh·gelectrode−1). PMID:28198419

  14. Statistics of superior records

    Science.gov (United States)

    Ben-Naim, E.; Krapivsky, P. L.

    2013-08-01

    We study statistics of records in a sequence of random variables. These identical and independently distributed variables are drawn from the parent distribution ρ. The running record equals the maximum of all elements in the sequence up to a given point. We define a superior sequence as one where all running records are above the average record expected for the parent distribution ρ. We find that the fraction of superior sequences SN decays algebraically with sequence length N, SN˜N-β in the limit N→∞. Interestingly, the decay exponent β is nontrivial, being the root of an integral equation. For example, when ρ is a uniform distribution with compact support, we find β=0.450265. In general, the tail of the parent distribution governs the exponent β. We also consider the dual problem of inferior sequences, where all records are below average, and find that the fraction of inferior sequences IN decays algebraically, albeit with a different decay exponent, IN˜N-α. We use the above statistical measures to analyze earthquake data.

  15. Frenillo labial superior doble

    Directory of Open Access Journals (Sweden)

    Carlos Albornoz López del Castillo

    Full Text Available El frenillo labial superior doble no sindrómico es una anomalía del desarrollo que no hemos encontrado reportada en la revisión bibliográfica realizada. Se presenta una niña de 11 años de edad que fue remitida al servicio de Cirugía Maxilofacial del Hospital "Eduardo Agramonte Piña", de Camagüey, por presentar un frenillo labial superior doble de baja inserción. Se describen los síntomas clínicos asociados a esta anomalía y el tratamiento quirúrgico utilizado para su solución: una frenectomía y plastia sobre la banda muscular frénica anormal que provocaba exceso de tejido en la mucosa labial. Consideramos muy interesante la descripción de este caso, por no haber encontrado reporte similar en la literatura revisada.

  16. Superior electrochemical performance of mesoporous Fe{sub 3}O{sub 4}/CNT nanocomposites as anode material for lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Abbas, Syed Mustansar, E-mail: qau_abbas@yahoo.com [Nanoscience and Catalysis Division, National Centre for Physics, Islamabad (Pakistan); Department of Chemistry, Quaid-e-Azam University, Islamabad (Pakistan); Ali, Saqib, E-mail: drsa54@yahoo.com [Department of Chemistry, Quaid-e-Azam University, Islamabad (Pakistan); Niaz, Niaz Ahmad [Department of Physics, Bahauddin Zakariya University, Multan (Pakistan); Ali, Nisar; Ahmed, Rashid [Department of Physics, Faculty of Science, University Teknologi Malaysia, Skudai, Johor (Malaysia); Ahmad, Nisar [Nanoscience and Catalysis Division, National Centre for Physics, Islamabad (Pakistan)

    2014-10-25

    Graphical abstract: The mesoporous Fe{sub 3}O{sub 4}/CNT nanocomposite synthesized via a modified co-precipitation method in combination with subsequent calcination was applied in the negative electrode materials for lithium ion batteries and exhibited high electrochemical performance. - Highlights: • Nanocomposite of functionalized CNTs with Fe{sub 3}O{sub 4} nanoparticles is prepared. • Good quality interfacial adhesion between CNTs and Fe{sub 3}O{sub 4} matrix. • High discharge capacity of 1093 mA h g{sup −1} after 50 cycles. • 50th Cycle coulombic efficiency of 98.4% at a current density of 100 mA g{sup −1}. - Abstract: A series of Fe{sub 3}O{sub 4}/CNT nanocomposites are effectively synthesized by an in situ chemical co-precipitation technique. The structure, morphology and chemical composition of synthesized nanocomposites are analyzed by X-ray diffraction, Rutherford backscattering spectroscopy, scanning electron microscopy, transmission electron microscopy and fourier-transform infrared spectroscopy. The electrochemical performance of synthesized nanocomposites is tested by cyclic voltammetry (CV), charge/discharge studies and electrochemical impedance spectroscopy (EIS). The carbon nanotubes are nicely dispersed in the Fe{sub 3}O{sub 4} nanoparticles for all the nanocomposites. Due to the synergistic effect arising from Fe{sub 3}O{sub 4} nanoparticles and carbon nanotubes, the electrochemical properties of pure Fe{sub 3}O{sub 4} material is considerably enhanced. A discharge capacity of 1093 mA h g{sup −1} is demonstrated by Fe{sub 3}O{sub 4}–7%CNT nanocomposite at a current density of 100 mA g{sup −1} with a high columbic efficiency of 98.4%. Moreover, this nanocomposite shows a stable cycling and rate performance at higher current densities. Hence, based on the above studies, such Fe{sub 3}O{sub 4}/CNT nanocomposite could be a possible contributor for lithium ion batteries.

  17. Synthesis of Pt/K2CO3/MgAlOx–reduced graphene oxide hybrids as promising NOx storage–reduction catalysts with superior catalytic performance

    Science.gov (United States)

    Mei, Xueyi; Yan, Qinghua; Lu, Peng; Wang, Junya; Cui, Yuhan; Nie, Yu; Umar, Ahmad; Wang, Qiang

    2017-02-01

    Pt/K2CO3/MgAlOx–reduced graphene oxide (Pt/K/MgAlOx–rGO) hybrids were synthesized, characterized and tested as a promising NOx storage and reduction (NSR) catalyst. Mg–Al layered double hydroxides (LDHs) were grown on rGO via in situ hydrothermal crystallization. The structure and morphology of samples were thoroughly characterized using various techniques. Isothermal NOx adsorption tests indicated that MgAlOx–rGO hybrid exhibited better NOx trapping performance than MgAlOx, from 0.44 to 0.61 mmol · g‑1, which can be attributed to the enhanced particle dispersion and stabilization. In addition, a series of MgAlOx–rGO loaded with 2 wt% Pt and different loadings (5, 10, 15, and 20 wt%) of K2CO3 (denoted as Pt/K/MgAlOx–rGO) were obtained by sequential impregnation. The influence of 5% H2O on the NOx storage capacity of MgAlOx–rGO loaded with 2 wt% Pt and 10% K2CO3 (2Pt/10 K/MgAlOx–rGO) catalyst was also evaluated. In all, the 2Pt/10 K/MgAlOx–rGO catalyst not only exhibited high thermal stability and NOx storage capacity of 1.12 mmol · g‑1, but also possessed excellent H2O resistance and lean–rich cycling performance, with an overall 78.4% of NOx removal. This work provided a new scheme for the preparation of highly dispersed MgAlOx–rGO hybrid based NSR catalysts.

  18. Synthesis of Pt/K2CO3/MgAlOx–reduced graphene oxide hybrids as promising NOx storage–reduction catalysts with superior catalytic performance

    Science.gov (United States)

    Mei, Xueyi; Yan, Qinghua; Lu, Peng; Wang, Junya; Cui, Yuhan; Nie, Yu; Umar, Ahmad; Wang, Qiang

    2017-01-01

    Pt/K2CO3/MgAlOx–reduced graphene oxide (Pt/K/MgAlOx–rGO) hybrids were synthesized, characterized and tested as a promising NOx storage and reduction (NSR) catalyst. Mg–Al layered double hydroxides (LDHs) were grown on rGO via in situ hydrothermal crystallization. The structure and morphology of samples were thoroughly characterized using various techniques. Isothermal NOx adsorption tests indicated that MgAlOx–rGO hybrid exhibited better NOx trapping performance than MgAlOx, from 0.44 to 0.61 mmol · g−1, which can be attributed to the enhanced particle dispersion and stabilization. In addition, a series of MgAlOx–rGO loaded with 2 wt% Pt and different loadings (5, 10, 15, and 20 wt%) of K2CO3 (denoted as Pt/K/MgAlOx–rGO) were obtained by sequential impregnation. The influence of 5% H2O on the NOx storage capacity of MgAlOx–rGO loaded with 2 wt% Pt and 10% K2CO3 (2Pt/10 K/MgAlOx–rGO) catalyst was also evaluated. In all, the 2Pt/10 K/MgAlOx–rGO catalyst not only exhibited high thermal stability and NOx storage capacity of 1.12 mmol · g−1, but also possessed excellent H2O resistance and lean–rich cycling performance, with an overall 78.4% of NOx removal. This work provided a new scheme for the preparation of highly dispersed MgAlOx–rGO hybrid based NSR catalysts. PMID:28205630

  19. Effect of the application of an electric field on the performance of a two-phase loop device: preliminary results

    Science.gov (United States)

    Creatini, F.; Di Marco, P.; Filippeschi, S.; Fioriti, D.; Mameli, M.

    2015-11-01

    In the last decade, the continuous development of electronics has pointed out the need for a change in mind with regard to thermal management. In the present scenario, Pulsating Heat Pipes (PHPs) are novel promising two-phase passive heat transport devices that seem to meet all present and future thermal requirements. Nevertheless, PHPs governing phenomena are quite unique and not completely understood. In particular, single closed loop PHPs manifest several drawbacks, mostly related to the reduction of device thermal performance and reliability, i.e. the occurrence of multiple operational quasi-steady states. The present research work proposes the application of an electric field as a technique to promote the circulation of the working fluid in a preferential direction and stabilize the device operation. The tested single closed loop PHP is made of a copper tube with an inner tube diameter equal to 2.00 mm and filled with pure ethanol (60% filling ratio). The electric field is generated by a couple of wire-shaped electrodes powered with DC voltage up to 20 kV and laid parallel to the longitudinal axis of the glass tube constituting the adiabatic section. Although the electric field intensity in the working fluid region is weakened both by the polarization phenomenon of the working fluid and by the interposition of the glass tube, the experimental results highlight the influence of the electric field on the device thermal performance and encourage the continuation of the research in this direction.

  20. Superiority of branched side chains in spontaneous nanowire formation: exemplified by poly(3-2-methylbutylthiophene) for high-performance solar cells.

    Science.gov (United States)

    Chen, Hsieh-Chih; Wu, I-Che; Hung, Jui-Hsiang; Chen, Fu-Je; Chen, I-Wen P; Peng, Yung-Kang; Lin, Chao-Sung; Chen, Chun-Hsien; Sheng, Yu-Jane; Tsao, Heng-Kwong; Chou, Pi-Tai

    2011-04-18

    One-dimensional nanostructures containing heterojunctions by conjugated polymers, such as nanowires, are expected to greatly facilitate efficient charge transfer in bulk-heterojunction (BHJ) solar cells. Thus, a combined theoretical and experimental approach is pursued to explore spontaneous nanowire formation. A dissipative particle dynamics simulation is first performed to study the morphologies formed by rodlike polymers with various side-chain structures. The results surprisingly predict that conjugated polymers with branched side chains are well suited to form thermodynamically stable nanowires. Proof of this concept is provided via the design and synthesis of a branched polymer of regioregular poly(3-2-methylbutylthiophene) (P3MBT), which successfully demonstrates highly dense nanowire formation free from any stringent conditions and stratagies. In BHJ solar cells fabricated using a blend of P3MBT and [6,6]-phenyl-C71-butyric acid methyl ester (PC(71) BM), P3MBT polymers are self-organized into highly crystalline nanowires with a d(100) spacing of 13.30 Å. The hole mobility of the P3MBT:PC(71) BM (1:0.5 by weight) blend film reaches 3.83 × 10(-4) cm(2) V(-1) s(-1) , and the maximum incident photon-to-current efficiency reaches 68%. The results unambiguously prove the spontaneous formation of nanowires using solution-processable conjugated polymers with branched alkyl side chains in BHJ solar cells.

  1. Electrically Insulative Performances of Ceramic and Clay Films Deposited via Supersonic Spraying

    Science.gov (United States)

    Lee, Jong-Gun; Kim, Do-Yeon; Joshi, Bhavana N.; Lee, Jong-Hyuk; Lee, Tae-Kyu; Kim, Jang-soo; Yang, Dae-ho; Kim, Woo-Young; Al-Deyab, Salem S.; Yoon, Sam S.

    2016-04-01

    Supersonic spray coating techniques were applied to deposit ceramic and clay particles as films for use in electrical insulation. TiO2 and Al2O3 ceramics were aerosol-deposited under vacuum while kaolinite, montmorillonite, and bentonite clays were deposited by cold spraying in open air. The electrical resistivity of Al2O3 and TiO2 were ~109 and ~108 Ω cm, respectively. The resistivity of kaolinite and montmorillonite were ~1012 Ω cm. Bentonite showed the lowest electrical resistivity of ~109 Ω cm among the clays because of the high cation exchange capacity of the material. The film surface morphologies and mechanical properties in the form of hardness and scratchability were also investigated.

  2. Analysis of electrical and magnetic bio-signals associated with motor performance and fatigue

    Science.gov (United States)

    Yao, Bing

    This dissertation reports findings centered principally on comprehensive research related to human bio-signals (EEG, MEG, EMG and fMRI) acquired during repetitive maximal voluntary contractions (MVC) that induced severe fatigue. Fatigue is a common experience that reduces productivity and quality of life and increases chances of injury. Although abundant information has been gained in the last several decades regarding muscular and spinal-level mechanisms of muscle fatigue, very little is known about how cortical centers control and respond to fatigue. The main purpose of this study was to examine the fatigue effects on the central nervous system by analyzing the bio-signals collected in the designed experiments. Healthy human subjects were asked to perform a series of repetitive handgrip MVCs with their dominant hand until exhaustion. Handgrip forces, electrical activity (EMG) from primary and non-primary muscles, and EEG, MEG, or fMRI signals from different locations of the brain were recorded simultaneously. The time series data were segmented into several physiologically meaningful epochs (time phases), from rest to preparation to movement execution/sustaining. A series of studies, including motor-related cortical potential (MRCP) analysis, power spectrum analysis, time-frequency (spectrogram) analysis of EEG, EEG source localization and nonlinear analysis (fractal dimension and largest Lyapunov exponent), and fMRI analysis, was applied to the data. We hypothesized that the fatigue effects would act differently on brain signals of different phases. The MRCP results showed that the negative potential (NP) related to motor task preparation only had minimal changes with fatigue. The power of all EEG frequencies did not alter significantly during the preparation phase but decreased significantly during the sustained phase of the contraction. The fractal dimension and the largest Lyapunov exponent decreased significantly during the sustained phase as fatigue

  3. Transcranial Electrical Stimulation to Enhance Cognitive Performance of Healthy Minors: A Complex Governance Challenge

    Science.gov (United States)

    Schuijer, Jantien W.; de Jong, Irja M.; Kupper, Frank; van Atteveldt, Nienke M.

    2017-01-01

    An increasing number of healthy adolescents are consuming products that can enhance their cognitive performance in educational settings. Currently, the use of pharmaceuticals is the most widely discussed enhancement method in the literature, but new evidence suggests that other methods based on Transcranial Electrical Stimulation (tES) also have potential as cognitive enhancer. Just like pharmaceutical enhancers, the availability and education-related use of tES-devices raise a broad range of ethical, legal, and societal issues that need to be addressed by policy-makers. Few studies, however, have specifically explored these issues in relation to child wellbeing. In this narrative review with systematic search, we describe the issues for child wellbeing that could arise from the availability and education-related use of tES-based enhancers by healthy minors. We demonstrate that the issues form a complex web of uncertainties and concerns, which are mainly incited by two factors. First is the high level of factual uncertainty due to gaps in empirical evidence about the exact working mechanisms and efficacy of tES. Moreover, a lack of insight into the technique’s (long-term) effects on healthy developing brains, and uncertainties about potential cognitive trade-offs have fueled concerns about the technique’s safety and impact. The second factor that contributes to the complexity of issues is the presence of moral diversity in our society. Different opinions exist on whether a certain enhancement effect would be desirable and whether potential risks would be acceptable. These opinions depend on one’s moral perspective, and the way one interprets and weights values such as the child’s autonomy and authenticity. The challenge for proper governance resides in the design of an appropriate framework that is capable of balancing the different moral perspectives in society, while recognizing the uncertainties that still exist. We therefore argue for a responsible

  4. MnO(x) Nanoparticle-Dispersed CeO2 Nanocubes: A Remarkable Heteronanostructured System with Unusual Structural Characteristics and Superior Catalytic Performance.

    Science.gov (United States)

    Putla, Sudarsanam; Amin, Mohamad Hassan; Reddy, Benjaram M; Nafady, Ayman; Al Farhan, Khalid A; Bhargava, Suresh K

    2015-08-05

    Understanding the interface-induced effects of heteronanostructured catalysts remains a significant challenge due to their structural complexity, but it is crucial for developing novel applied catalytic materials. This work reports a systematic characterization and catalytic evaluation of MnOx nanoparticle-dispersed CeO2 nanocubes for two important industrial applications, namely, diesel soot oxidation and continuous-flow benzylamine oxidation. The X-ray diffraction and Raman studies reveal an unusual lattice expansion in CeO2 after the addition of MnOx. This interesting observation is due to conversion of smaller sized Ce(4+) (0.097 nm) to larger sized Ce(3+) (0.114 nm) in cerium oxide led by the strong interaction between MnOx and CeO2 at their interface. Another striking observation noticed from transmission electron microscopy, high angle annular dark-field scanning transmission electron microscopy, and electron energy loss spectroscopy studies is that the MnOx species are well-dispersed along the edges of the CeO2 nanocubes. This remarkable decoration leads to an enhanced reducible nature of the cerium oxide at the MnOx/CeO2 interface. It was found that MnOx/CeO2 heteronanostructures efficiently catalyze soot oxidation at lower temperatures (50% soot conversion, T50 ∼660 K) compared with that of bare CeO2 nanocubes (T50 ∼723 K). Importantly, the MnOx/CeO2 heteronanostructures exhibit a noticeable steady performance in the oxidation of benzylamine with a high selectivity of the dibenzylimine product (∼94-98%) compared with that of CeO2 nanocubes (∼69-91%). The existence of a strong synergistic effect at the interface sites between the CeO2 and MnOx components is a key factor for outstanding catalytic efficiency of the MnOx/CeO2 heteronanostructures.

  5. Phase Tuning of Nanostructured Gallium Oxide via Hybridization with Reduced Graphene Oxide for Superior Anode Performance in Li-Ion Battery: An Experimental and Theoretical Study.

    Science.gov (United States)

    Patil, Sharad B; Kim, In Young; Gunjakar, Jayavant L; Oh, Seung Mi; Eom, Taedaehyeong; Kim, Hyungjun; Hwang, Seong-Ju

    2015-08-26

    The crystal phase of nanostructured metal oxide can be effectively controlled by the hybridization of gallium oxide with reduced graphene oxide (rGO) at variable concentrations. The change of the ratio of Ga2O3/rGO is quite effective in tailoring the crystal structure and morphology of nanostructured gallium oxide hybridized with rGO. This is the first example of the phase control of metal oxide through a change of the content of rGO hybridized. The calculations based on density functional theory (DFT) clearly demonstrate that the different surface formation energy and Ga local symmetry of Ga2O3 phases are responsible for the phase transition induced by the change of rGO content. The resulting Ga2O3-rGO nanocomposites show promising electrode performance for lithium ion batteries. The intermediate Li-Ga alloy phases formed during the electrochemical cycling are identified with the DFT calculations. Among the present Ga2O3-rGO nanocomposites, the material with mixed α-Ga2O3/β-Ga2O3/γ-Ga2O3 phase can deliver the largest discharge capacity with the best cyclability and rate characteristics, highlighting the importance of the control of Ga2O3/rGO ratio in optimizing the electrode activity of the composite materials. The present study underscores the usefulness of the phase-control of nanostructured metal oxides achieved by the change of rGO content in exploring novel functional nanocomposite materials.

  6. Key Performance Parameter Driven Technology Goals for Electric Machines and Power Systems

    Science.gov (United States)

    Bowman, Cheryl; Jansen, Ralph; Brown, Gerald; Duffy, Kirsten; Trudell, Jeffrey

    2015-01-01

    Transitioning aviation to low carbon propulsion is one of the crucial strategic research thrust and is a driver in the search for alternative propulsion system for advanced aircraft configurations. This work requires multidisciplinary skills coming from multiple entities. The feasibility of scaling up various electric drive system technologies to meet the requirements of a large commercial transport is discussed in terms of key parameters. Functional requirements are identified that impact the power system design. A breakeven analysis is presented to find the minimum allowable electric drive specific power and efficiency that can preserve the range, initial weight, operating empty weight, and payload weight of the base aircraft.

  7. Contact-geometry engineering in a circular light-emitting diode (LED) for improved electrical and optical performances

    Science.gov (United States)

    Park, Yun Soo; Lee, Hwan Gi; Yang, Chung-Mo; Kim, Dong-Seok; Bae, Jin-Hyuk; Cho, Seongjae; Lee, Jung-Hee; Kang, In Man

    2013-01-01

    GaN light-emitting diodes (LEDs) based on circular mesa structure are fabricated and their electrical and optical characterizations are performed. The uniform current flow in the circular LED (C-LED) was conducted in the radial direction, from the n-type GaN island electrode at the center to the p-type GaN ring electrode around the perimeter. The symmetric electrode structuring substantially improved the electrical and optical performances. The operating voltage for C-LED at a reference current (100 mA) was 20.9% lower than that of a conventionally structured LED (CV-LED). Also, C-LED showed 19.4% higher optical output power than CV-LED.

  8. Investigation of dielectric substrates on electrical and optical performance of wafer-scale graphene using non-contact methods

    Science.gov (United States)

    Wang, Dong; Ning, Jing; Zhang, Jincheng; Guo, Lixin; Hao, Yue

    2017-10-01

    Here we systemically discussed the influence of dielectric substrates on the surface morphology, electrical and optical performance of transferred graphene. The electrical properties were investigated using a microwave-probing technique without metal-graphene contact. We found that a complex mechanism governed the influence of the surface properties of the dielectric substrates, such as morphology, hydrophilicity, crystallinity, and polarization, on the performance of the graphene. We also found that graphene on r-Al2O3 was more effective for graphene-based devices with a high carrier mobility of ˜5000 cm2 V-1 s-1. This provides a new method to choose the most suitable substrate for fabricating graphene-based devices.

  9. The Electrical Performance of Polyamide 66/Poly(vinylidene fluoride with Vinyl Acetate-Maleic Anhydride Copolymer

    Directory of Open Access Journals (Sweden)

    Rui Li

    2016-01-01

    Full Text Available The electric performance of the PA66/PVDF blends filled with various amount of copolymer synthesized from vinyl acetate-maleic anhydride (VAMA was investigated. PA66/VAMA/PVDF blends show high dielectric constants, low dielectric loss, and excellent breakdown strength, which were important indexes in the actual application of dielectric material. The VAMA copolymer improves the dielectric and piezoelectric performance of the PA66/PVDF blends. Meanwhile, the addition of VAMA obviously decreases the dielectric loss and breakdown strength of the blends. PA66/PVDF blends filled with 3 wt% VAMA exhibited the best electric ability. The stable dielectric constants of the all-polymeric blends can be tuned by adjusting the content of the VAMA. The created all-polymeric blends represent a novel dielectric material that is technologically simple and easy to process forward application for flexible electronics.

  10. Ag/g-C3N4 catalyst with superior catalytic performance for the degradation of dyes: a borohydride-generated superoxide radical approach

    Science.gov (United States)

    Fu, Yongsheng; Huang, Ting; Zhang, Lili; Zhu, Junwu; Wang, Xin

    2015-08-01

    dissolved oxygen in the presence of BH4- and the synergistic effect of Ag nanoparticles and g-C3N4. Electronic supplementary information (ESI) available: The typical experimental details for the color reaction between the ferrous irons (Fe2+) and nitric oxide (NO); MO photodegradation performances in the presence of Ag/g-C3N4 or Ag/g-C3N4/TiO2 nanocomposites; TEM image of the pure g-C3N4 catalyst; The remaining MO, MB and NDY-GL in solution after reaching the adsorption-desorption equilibrium in the dark for 60 min with stirring; Catalytic degradation of MB and NDY-GL over the Ag/g-C3N4-4 catalyst in the presence of BH4- in the dark and under visible light irradiation. See DOI: 10.1039/c5nr03260a

  11. 77 FR 22391 - Standards of Performance for Greenhouse Gas Emissions for New Stationary Sources: Electric...

    Science.gov (United States)

    2012-04-13

    ... report, ``Each additional ton of greenhouse gases emitted commits us to further change and greater risks... Greenhouse Gas Concentrations; Board on Atmospheric Sciences and Climate, Division of Earth and Life Sciences... Greenhouse Gas Emissions for New Stationary Sources; Electric Utility Generating Units; Proposed Rule...

  12. Evaluation of Fuel-Cell Range Extender Impact on Hybrid Electrical Vehicle Performance

    DEFF Research Database (Denmark)

    Jensen, Hans-Christian Becker; Schaltz, Erik; Koustrup, Per Sune

    2013-01-01

    of a vehicle with an internal combustion engine (ICE). Fuel cells (FCs) can be added to an EV as an additional energy source. These are faster to refill and will therefore facilitate the transition from vehicles running on fossil fuel to electricity. Different EV setups with FC strategies are presented...

  13. Evaluation of Fuel-Cell Range Extender Impact on Hybrid Electrical Vehicle Performance

    DEFF Research Database (Denmark)

    Jensen, Hans-Christian Becker; Schaltz, Erik; Koustrup, Per Sune

    2013-01-01

    of a vehicle with an internal combustion engine (ICE). Fuel cells (FCs) can be added to an EV as an additional energy source. These are faster to refill and will therefore facilitate the transition from vehicles running on fossil fuel to electricity. Different EV setups with FC strategies are presented...

  14. A novel 3D energetic MOF of high energy content: synthesis and superior explosive performance of a Pb(ii) compound with 5,5'-bistetrazole-1,1'-diolate.

    Science.gov (United States)

    Shang, Yu; Jin, Bo; Peng, Rufang; Liu, Qiangqiang; Tan, Bisheng; Guo, Zhicheng; Zhao, Jun; Zhang, Qingchun

    2016-09-21

    The development of high-performance insensitive energetic materials is important because of the increasing demand for these materials in military and civilian applications. A novel 3D energetic metal-organic framework (MOF) of exceptionally high energy content, [Pb(BTO)(H2O)]n, was synthesized and structurally characterized by single crystal X-ray diffraction, featuring a three-dimensional parallelogram porous framework, where BTO represents 5,5'-bistetrazole-1,1'-diolate. The thermal stability and energetic properties were determined, exhibiting good thermostability (Td = 309.0 °C), excellent detonation pressure (P) of 53.06 GPa, a detonation velocity (D) of 9.204 km s(-1), and acceptable sensitivity to confirmed impact (IS = 7.5 J). Notably, the complex possesses unprecedented superior density than the reported energetic MOFs. The results highlight this new MOF as a potential energetic material.

  15. Performance-based ratemaking for electric utilities: Review of plans and analysis of economic and resource-planning issues. Volume 2, Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Comnes, G.A.; Stoft, S.; Greene, N. [Lawrence Berkeley Lab., CA (United States); Hill, L.J. [Oak Ridge National Lab., TN (United States)

    1995-11-01

    This document contains summaries of the electric utilities performance-based rate plans for the following companies: Alabama Power Company; Central Maine Power Company; Consolidated Edison of New York; Mississippi Power Company; New York State Electric and Gas Corporation; Niagara Mohawk Power Corporation; PacifiCorp; Pacific Gas and Electric; Southern California Edison; San Diego Gas & Electric; and Tucson Electric Power. In addition, this document also contains information about LBNL`s Power Index and Incentive Properties of a Hybrid Cap and Long-Run Demand Elasticity.

  16. Efficient plasma-enhanced method for layered LiNi1/3Co1/3Mn1/3O2 cathodes with sulfur atom-scale modification for superior-performance Li-ion batteries.

    Science.gov (United States)

    Jiang, Qianqian; Chen, Ning; Liu, Dongdong; Wang, Shuangyin; Zhang, Han

    2016-06-01

    In order to improve the electrochemical performance of LiNi1/3Co1/3Mn1/3O2 as a lithium insertion positive electrode material, atom-scale modification was realized to obtain the layered oxysulfide LiNi1/3Co1/3Mn1/3O2-xSx using a novel plasma-enhanced doping strategy. The structure and electrochemical performance of LiNi1/3Co1/3Mn1/3O2-xSx are investigated systematically, which confirms that the S doping can make the structure stable and benefit the electrochemical performance. The phys-chemical characterizations indicate that oxygen atoms in the initial LiNi1/3Co1/3Mn1/3O2 have been partially replaced by S atoms. It should be pointed out that the atom-scale modification does not significantly alter the intrinsic structure of the cathode. Compared to the pristine material, the LiNi1/3Co1/3Mn1/3O2-xSx shows a superior performance with a higher capacity (200.4 mA h g(-1)) and a significantly improved cycling stability (maintaining 94.46% of its initial discharge capacity after 100 cycles). Moreover, it has an excellent rate performance especially at elevated performance, which is probably due to the faster Li(+) transportation after S doping into the layered structure. All the results show that the atom-scale modification with sulfur atoms on LiNi1/3Co1/3Mn1/3O2, which significantly improved the electrochemical performance, offers a novel anionic doping strategy to realize the atom-scale modification of electrode materials to improve their electrochemical performance.

  17. Performance y participación: telecomunicación, espacio electrónico y activación.

    OpenAIRE

    Simó Mulet, Toni; Segura Cabañero, Jesús

    2011-01-01

    Bruce Nauman, Jeffrey Shaw, Nicolai/Peljhan representan una selección de artistas que han trabajado en la performance y el video arte. Este trabajo es un recorrido por artistas que en su proceso artístico han utilizado los medios interactivos de la telecomunicación, el espacio electrónico y la activación de los espectadores.

  18. Electrical Rating of Concentrated Photovoltaic (CPV) Systems: Long-Term Performance Analysis and Comparison to Conventional PV Systems

    KAUST Repository

    Burhan, Muhammad

    2016-02-29

    The dynamic nature of meteorological data and the commercial availability of diverse photovoltaic systems, ranging from single-junction silicon-based PV panels to concentrated photovoltaic (CPV) systems utilizing multi-junction solar cells and a two-axis solar tracker, demand a simple but accurate methodology for energy planners and PV system designers to understand the economic feasibility of photovoltaic or renewable energy systems. In this paper, an electrical rating methodology is proposed that provides a common playing field for planners, consumers and PV manufacturers to evaluate the long-term performance of photovoltaic systems, as long-term electricity rating is deemed to be a quick and accurate method to evaluate economic viability and determine plant sizes and photovoltaic system power production. A long-term performance analysis based on monthly and electrical ratings (in kWh/m2/year) of two developed CPV prototypes, the Cassegrain mini dish and Fresnel lens CPVs with triple-junction solar cells operating under the meteorological conditions of Singapore, is presented in this paper. Performances are compared to other conventional photovoltaic systems.

  19. Integrated DEA Models and Grey System Theory to Evaluate Past-to-Future Performance: A Case of Indian Electricity Industry

    Directory of Open Access Journals (Sweden)

    Chia-Nan Wang

    2015-01-01

    Full Text Available The growth of economy and population together with the higher demand in energy has created many concerns for the Indian electricity industry whose capacity is at 211 gigawatts mostly in coal-fired plants. Due to insufficient fuel supply, India suffers from a shortage of electricity generation, leading to rolling blackouts; thus, performance evaluation and ranking the industry turn into significant issues. By this study, we expect to evaluate the rankings of these companies under control of the Ministry of Power. Also, this research would like to test if there are any significant differences between the two DEA models: Malmquist nonradial and Malmquist radial. Then, one advance model of MPI would be chosen to see these companies’ performance in recent years and next few years by using forecasting results of Grey system theory. Totally, the realistic data 14 are considered to be in this evaluation after the strict selection from the whole industry. The results found that all companies have not shown many abrupt changes on their scores, and it is always not consistently good or consistently standing out, which demonstrated the high applicable usability of the integrated methods. This integrated numerical research gives a better “past-present-future” insights into performance evaluation in Indian electricity industry.

  20. Integrated DEA models and grey system theory to evaluate past-to-future performance: a case of Indian electricity industry.

    Science.gov (United States)

    Wang, Chia-Nan; Nguyen, Nhu-Ty; Tran, Thanh-Tuyen

    2015-01-01

    The growth of economy and population together with the higher demand in energy has created many concerns for the Indian electricity industry whose capacity is at 211 gigawatts mostly in coal-fired plants. Due to insufficient fuel supply, India suffers from a shortage of electricity generation, leading to rolling blackouts; thus, performance evaluation and ranking the industry turn into significant issues. By this study, we expect to evaluate the rankings of these companies under control of the Ministry of Power. Also, this research would like to test if there are any significant differences between the two DEA models: Malmquist nonradial and Malmquist radial. Then, one advance model of MPI would be chosen to see these companies' performance in recent years and next few years by using forecasting results of Grey system theory. Totally, the realistic data 14 are considered to be in this evaluation after the strict selection from the whole industry. The results found that all companies have not shown many abrupt changes on their scores, and it is always not consistently good or consistently standing out, which demonstrated the high applicable usability of the integrated methods. This integrated numerical research gives a better "past-present-future" insights into performance evaluation in Indian electricity industry.

  1. Magnetic resonance imaging evaluation of meniscoid superior labrum: normal variant or superior labral tear*

    Science.gov (United States)

    Simão, Marcelo Novelino; Vinson, Emily N.; Spritzer, Charles E.

    2016-01-01

    Objective The objective of this study was to determine the incidence of a "meniscoid" superior labrum. Materials and Methods This was a retrospective analysis of 582 magnetic resonance imaging examinations of shoulders. Of those 582 examinations, 110 were excluded, for a variety of reasons, and the final analysis therefore included 472 cases. Consensus readings were performed by three musculoskeletal radiologists using specific criteria to diagnose meniscoid labra. Results A meniscoid superior labrum was identified in 48 (10.2%) of the 472 cases evaluated. Arthroscopic proof was available in 21 cases (43.8%). In 10 (47.6%) of those 21 cases, the operative report did not include the mention a superior labral tear, thus suggesting the presence of a meniscoid labrum. In only one of those cases were there specific comments about a mobile superior labrum (i.e., meniscoid labrum). In the remaining 11 (52.4%), surgical correlation demonstrated superior labral tears. Conclusion A meniscoid superior labrum is not an infrequent finding. Depending upon assumptions and the requirement of surgical proof, the prevalence of a meniscoid superior labrum in this study was between 2.1% (surgically proven) and 4.8% (projected). However, superior labral tears are just as common and are often confused with meniscoid labra. PMID:27777474

  2. Electric and mechanical performances of Bi0.5Sb1.5Te3 prepared by spark plasma sintering

    Institute of Scientific and Technical Information of China (English)

    XIAO Bo; CHEN Hui; WU Borong; ZHU Lei; LIU Mingyi; JIAN Xuyu; LI Lin

    2006-01-01

    Thermoelectric (TE) materials are a kind of functional materials which can be used to convert directly heat energy to electricity or reversely.The thermoelectric effects hold great potential for application in power generation and refrigeration.Bi2Te3 and its alloys are well known as best TE materials currently available near room temperature.This paper studies respectively the effects of spark plasma sintering (SPS) on electric performance of Bi0.5Sb1.5Te3 thermoelectric materials that are prepared through vacuum melting and ball milling.Through X-ray Diffraction and cold field emission scanning electric microscope s4800, the phase constituent and microstructure of the TE materials samples were analyzed.Electric conductivity and power factor can be improved with the rise of Spark Plasma Sintering temperature (from 300 to 500 ℃) and pressure(from 30 to 60 MPa), and the density and mechanical strength of Bi0.5Sb1.5Te3 thermoelectric material increase, too.

  3. Preparation and improved electrical performance of the Pr-doped CaMnO3-δ thermoelectric compound

    Science.gov (United States)

    Zhang, F. P.; Lu, Q. M.; Zhang, X.; Zhang, J. X.

    2013-09-01

    The rare earth Pr-doped Ca1-xPrxMnO3-δ (0 ⩽ x ⩽ 0.14) compound bulk samples are fabricated by citrate acid sol-gel combined with the ceramic preparation method. The effects of Pr doping on the structural and electrical transport properties of CaMnO3-δ within the high-temperature region are investigated in detail. The results show that single orthorhombic compounds can be formed in the experimental doping region. The remarkably reduced electrical resistivity is observed for the doped samples with the minimum value 3.90 mΩ cm at 373 K for the x = 0.14 sample; the absolute value of the Seebeck coefficient is decreased due to electron carrier concentration enhancement. The electrical properties of the doped samples are optimized compared with that of the parent sample, and the x = 0.08 sample is found to have the largest power factor value of 0.334 mW m-1 K-2 at 873 K. It is confirmed from the investigation that the electrical performance could be improved remarkably by rare earth Pr doping at a lower content.

  4. A system-level mathematical model for evaluation of power train performance of load-leveled electric-vehicles

    Science.gov (United States)

    Purohit, G. P.; Leising, C. J.

    1984-01-01

    The power train performance of load leveled electric vehicles can be compared with that of nonload leveled systems by use of a simple mathematical model. This method of measurement involves a number of parameters including the degree of load leveling and regeneration, the flywheel mechanical to electrical energy fraction, and efficiencies of the motor, generator, flywheel, and transmission. Basic efficiency terms are defined and representative comparisons of a variety of systems are presented. Results of the study indicate that mechanical transfer of energy into and out of the flywheel is more advantageous than electrical transfer. An optimum degree of load leveling may be achieved in terms of the driving cycle, battery characteristics, mode of mechanization, and the efficiency of the components. For state of the art mechanically coupled flyheel systems, load leveling losses can be held to a reasonable 10%; electrically coupled systems can have losses that are up to six times larger. Propulsion system efficiencies for mechanically coupled flywheel systems are predicted to be approximately the 60% achieved on conventional nonload leveled systems.

  5. Improvement of proton exchange membrane fuel cell electrical performance by optimization of operating parameters and electrodes preparation

    Energy Technology Data Exchange (ETDEWEB)

    Kadjo, A.J.-J.; Garnier, J.-P.; Martemianov, S. [Laboratoire d' Etudes Thermiques, UMR6608, ESIP-Universite de Poitiers, CNRS, Poitiers F-86022 (France); Brault, P.; Caillard, A. [Groupe de Recherche sur l' Energetique des Milieux Ionises, UMR6606 Universite d' Orleans, CNRS Polytech' Orleans BP6744, F-45067 Orleans Cedex 2 (France); Coutanceau, C. [Laboratoire de Catalyse en Chimie Organique, UMR6503 Universite de Poitiers, CNRS, Poitiers F-86022 (France)

    2007-10-25

    The effect of operating parameters (cell temperature, humidifiers temperature, gases flows and pressures) on the performance of a 25 cm{sup 2} surface area fuel cell is performed. After optimization, a homemade MEA fitted with electrodes prepared via the colloidal route leads to achieve reproducibly maximum power densities higher than 1.2 W cm{sup -2} with a total catalyst loading of 0.7 mg{sub Pt} cm{sup -2} (corresponding to 1.7kW g{sub Pt}{sup -1}). This electrical performance is higher to that obtained with a commercial MEA provided by fuel cell store (total platinum loading of 1.2 mg cm{sup -2} and power density close to 1 W cm{sup -2}, corresponding to 0.75kW g{sub Pt}{sup -1}). Based on this experience, two different homemade MEAs are tested under optimal operating conditions and compared to the commercial one. The final goal is to decrease significantly the platinum loading preserving at least equivalent PEMFC electrical performance. The method of catalyst deposition by plasma sputtering is used to further decrease the total catalyst loading down to 0.45 mg{sub Pt} cm{sup -2}. Very interesting performances (close to 0.7 W cm{sup -2}) were obtained with this low-platinum loading MEA (corresponding to 1.6kW g{sub Pt}{sup -1}). However, it was shown that the decrease of the platinum loading in the cathode from 0.35 to 0.1 mg cm{sup -2} affects the kinetics of oxygen reduction (exchange current density j{sub 0} and Tafel slope b) and the resistance of the cell R, and hence the cell electrical performance. (author)

  6. The modulatory effect of electrical stimulation on the excitability of the corticospinal tract varies according to the type of muscle contraction being performed.

    Science.gov (United States)

    Saito, Kei; Sugawara, Kenichi; Miyaguchi, Shota; Matsumoto, Takuya; Kirimoto, Hikari; Tamaki, Hiroyuki; Onishi, Hideaki

    2014-01-01

    Afferent input caused by electrical stimulation of a peripheral nerve increases corticospinal excitability during voluntary contractions, indicating that proprioceptive sensory input arriving at the cortex plays a fundamental role in modulating corticospinal excitability. The purpose of this study was to investigate whether the effect of electrical stimulation on the corticospinal excitability varies according to the type of muscle contraction being performed. Motor-evoked potentials (MEPs) were elicited by transcranial magnetic stimulation (TMS) during a shortening contraction, an isometric contraction, or no contraction of the first dorsal interosseous (FDI) muscle. In some trials, electrical stimulation of the ulnar nerve was performed at 110% of the sensory threshold or 110% of the motor threshold prior to TMS. Electrical stimulation involved either a train of 50 pulses at 10 Hz or a single pulse. Shortening contraction with the train of electrical stimuli significantly increased MEP amplitudes, and the increase was dependent on the type of stimulation. Isometric contraction with the train of electrical stimuli and electrical stimulation without voluntary contraction did not affect MEP amplitudes. A single pulse of electrical stimulation did not affect MEP amplitudes in any condition. Thus, electrical-stimulation-induced modulation of corticospinal excitability varied according to the type of muscle contraction performed and the type of stimulation. These results show that the type of contraction should be considered when using electrical stimulation for rehabilitation in patients with central nervous system lesions.

  7. A Study on the Control Performance of Electronic Differential System for Four-Wheel Drive Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Dejun Yin

    2017-01-01

    Full Text Available The electronic differential system (EDS is an important issue for four-wheel drive electric vehicles. This paper delineates an advanced EDS steering strategy and carries out a careful study of its control performance by numerical simulations that comply with the requirements of ISO4238:2012. The results demonstrate that the EDS feedback gain plays an important role to its control performance, particularly to its steering characteristics. Moreover, the analysis and discussion disclose the mechanism of the relationship between the feedback gain and the steering characteristics, which will contribute to further research and EDS development.

  8. Electrical and Mechanical Performance of Carbon Fiber-Reinforced Polymer Used as the Impressed Current Anode Material

    Directory of Open Access Journals (Sweden)

    Ji-Hua Zhu

    2014-07-01

    Full Text Available An investigation was performed by using carbon fiber-reinforced polymer (CFRP as the anode material in the impressed current cathodic protection (ICCP system of steel reinforced concrete structures. The service life and performance of CFRP were investigated in simulated ICCP systems with various configurations. Constant current densities were maintained during the tests. No significant degradation in electrical and mechanical properties was found for CFRP subjected to anodic polarization with the selected applied current densities. The service life of the CFRP-based ICCP system was discussed based on the practical reinforced concrete structure layout.

  9. Significant manipulation of output performance of a bridge-structured spin valve magnetoresistance sensor via an electric field

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yue; Yan, Baiqian; Ou-Yang, Jun; Zhu, Benpeng; Chen, Shi; Yang, Xiaofei, E-mail: hust-yangxiaofei@163.com [School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074 (China); Wang, Xianghao [School of Information Engineering, Wuhan University of Technology, Wuhan 430070 (China)

    2016-01-28

    Through principles of spin-valve giant magnetoresistance (SV-GMR) effect and its application in magnetic sensors, we have investigated electric-field control of the output performance of a bridge-structured Co/Cu/NiFe/IrMn SV-GMR sensor on a PZN-PT piezoelectric substrate using the micro-magnetic simulation. We centered on the influence of the variation of uniaxial magnetic anisotropy constant (K) of Co on the output of the bridge, and K was manipulated via the stress of Co, which is generated from the strain of a piezoelectric substrate under an electric field. The results indicate that when K varies between 2 × 10{sup 4 }J/m{sup 3} and 10 × 10{sup 4 }J/m{sup 3}, the output performance can be significantly manipulated: The linear range alters from between −330 Oe and 330 Oe to between −650 Oe and 650 Oe, and the sensitivity is tuned by almost 7 times, making it possible to measure magnetic fields with very different ranges. According to the converse piezoelectric effect, we have found that this variation of K can be realized by applying an electric field with the magnitude of about 2–20 kV/cm on a PZN-PT piezoelectric substrate, which is realistic in application. This result means that electric-control of SV-GMR effect has potential application in developing SV-GMR sensors with improved performance.

  10. Superior-subordinate relations as organizational processes

    DEFF Research Database (Denmark)

    Asmuss, Birte; Aggerholm, Helle Kryger; Oshima, Sae

    Since the emergence of the practice turn in social sciences (Golsorkhi et al. 2010), studies have shown a number of institutionally relevant aspects as achievements across time and by means of various resources (human and non-human) (Taylor & van Every 2000, Cooren et al. 2006). Such a process view...... on organizational practices relates closely to an increased focus on communication as being constitutive of the organization in general and the superior-subordinate relationship in specific. The current study aims to contribute to this line of research by investigating micro-practices involved in establishing...... superior-subordinate relations in a specific institutionalized setting: performance appraisal interviews (PAIs). While one main task of PAIs is to manage and integrate organizational and employee performance (Fletcher, 2001:473), PAIs are also organizational practices where superior-subordinate relations...

  11. Mechanical and electrical performance of Roystonea regia/glass fibre reinforced epoxy hybrid composites

    Indian Academy of Sciences (India)

    Govardhan Goud; R N Rao

    2012-08-01

    The present paper investigates mechanical and electrical properties of Roystonea regia/glass fibre reinforced epoxy hybrid composites. Five varieties of hybrid composites have been prepared by varying the glass fibre loading. Roystonea regia (royal palm), a natural fibre was collected from the foliage of locally available royal palm tree through the process of water retting and mechanical extraction. Roystonea regia, -glass short fibres were used together as reinforcement in epoxy matrix to form hybrid composites. It has been observed that tensile, flexural, impact and hardness properties of hybrid composites considerably increased with increase in glass fibre loading. But electrical conductivity and dielectric constant values decreased with increase in glass fibre content in the hybrid composites at all frequencies. Scanning electron microscopy of fractured hybrid composites has been carried out to study the fibre matrix adhesion.

  12. Electrical and Mechanical Performance of an Enhanced Cable Insulation Scheme for Superconducting Magnets

    CERN Document Server

    Fessia, P; Luzieux, S; Tommasini, D; Gerardin, A; Guinchard, M; Regis, F; Sgobba, S; Zaghloul, A

    2010-01-01

    New polyimide cable insulation schemes improving the cooling of Nb-Ti superconducting coils were recently developed to face the severe heat loads at which the next generation of superconducting accelerator magnets will work. In order to qualify the new insulation, a test campaign was realized to assess both its electrical and mechanical features with respect to the standard LHC insulation. The electrical tests assessed the dielectric strength and inter-turn leakage current to be satisfactory. The mechanical tests investigated the insulation thickness under load and the stress relaxation at ambient temperature, thus providing essential information for the magnetic and mechanical design of the final focusing magnets for the LHC upgrade phase I.

  13. Performance of Microbial Fuel Cell for Wastewater Treatment and Electricity Generation

    Directory of Open Access Journals (Sweden)

    Z Yavari

    2013-06-01

    Full Text Available Renewable energy will have an important role as a resource of energy in the future. Microbial fuel cell (MFC is a promising method to obtain electricity from organic matter andwastewater treatment simultaneously. In a pilot study, use of microbial fuel cell for wastewater treatment and electricity generation investigated. The bacteria of ruminant used as inoculums. Synthetic wastewater used at different organic loading rate. Hydraulic retention time was aneffective factor in removal of soluble COD and more than 49% removed. Optimized HRT to achieve the maximum removal efficiency and sustainable operation could be regarded 1.5 and 2.5 hours. Columbic efficiency (CE affected by organic loading rate (OLR and by increasing OLR, CE reduced from 71% to 8%. Maximum voltage was 700mV. Since the microbial fuel cell reactor considered as an anaerobic process, it may be an appropriate alternative for wastewater treatment

  14. Strategic Optimization and Investigation Effect Of Process Parameters On Performance Of Wire Electric Discharge Machine (WEDM

    Directory of Open Access Journals (Sweden)

    ATUL KUMAR

    2012-06-01

    Full Text Available Wire electrical discharge machining (WEDM is widely used in machining of conductive materials when precision is of primary significance. Wire-cut electric discharge machining of Skd 61alloy has been considered in the present work. Experimentation has been completed by using Taguchi’s L18 (21x37 orthogonal array under different conditions of parameters. Optimal combinations of parameters were obtained by this technique. The study shows that with the minimum number of experiments the complete problem can be solvedwhen compared to full factorial design. Experimental results make obvious that the machining model is proper and the Taguchi’s method satisfies the practical conditions. The results obtained are analyzed for the selection of an optimal combination of WEDM parameters for proper machining of Skd 61 alloy to achieve better surface finish. Different analysis was made on the data obtained from the experiments.

  15. Prediction of College Performance of Superior Students.

    Science.gov (United States)

    Roberts, Roy J.

    1965-01-01

    Using 857 male National Merit Finalists and Commended Students, scales to predict 1st year college grades and science, writing, art, music, speech, and leadership achievement were developed by analysis of 906 pre-college questionnaire items. Two item analysis strategies were used: responses of achieving subjects (S's) and general samples of…

  16. Performance Attributional Effects on Feedback from Superiors

    Science.gov (United States)

    1981-06-01

    of the task and the general procedure. He then administered the Wonderlic Per- sonnel Test. Following completion of the test, a "random drawing" was...Upon arrival at the experimental session, the supervisor 7 and the three confederates were all administered the Wonderlic Personnel Test. Following

  17. Delegation: A Competency of Superior Performers?

    Science.gov (United States)

    1982-12-01

    subordinate, distribution of power and responsibility. Henri Fayol does no better with this subject in his classic fourteen principles of management. He...Structure and Behavior, Litterer, Joseph A., Wiley and Sons, Inc., New York, 1963. 4. Fayol , Henri , "General Principles of Management", from Classics...chain, As with Weber, Fayol concerns himself with systems in which positional delegation can occur, rather than with the individualized action this

  18. Improving energy performance power station of ship with integrated electric propulsion

    Directory of Open Access Journals (Sweden)

    Dar’enkov Andrey

    2017-01-01

    Full Text Available The article presents the method of calculating the power plant fuel consumption on the basis of diesel-generating installation (DGI with variable speed for ships with integrated electric propulsion. Application DGI with variable speed allows saving fuel and therefore reducing harmful emissions into the atmosphere. In the paper calculated the fuel efficiency of unified power station on the basis of a variable speed DGI power of 1000 kW.

  19. Improved performance of bipolar charge plasma transistor by reducing the horizontal electric field

    Science.gov (United States)

    Bramhane, Lokesh Kumar; Singh, Jawar

    2017-04-01

    In this paper, we have proposed a modified lateral bipolar charge plasma transistor (BCPT). The appropriate work function engineering is used to induce the electron-hole concentrations under different regions. The reduced work function difference and absence of oxide layer (tox) in the proposed lateral BCPT reduce the horizontal electric field (EX) at the emitter. Also, reduced work function difference at base metal contact decreases the electric field at base-emitter and base-collector junctions. 2-D TCAD simulations of the proposed device reveal that there are evenly spaced output characteristic curves, improved cut-off frequency and breakdown voltage. The reduction in horizontal electric field about one-fourth compared to the conventional lateral BCPT results in realistic current gain (β) and reduced on-set voltage makes proposed device suitable for low power applications. The proposed device exhibits improved cut-off frequency (fT = 7.5 GHz) compared to the lateral BCPT (3.7 GHz) and improved current gain (37.67) and same cut-off frequency (= 7.5 GHz) compared to the conventional BJT (β = 26.5 &fT = 7.5 GHz).

  20. Sobredentadura total superior implantosoportada

    Directory of Open Access Journals (Sweden)

    Luis Orlando Rodríguez García

    2010-06-01

    Full Text Available Se presenta un caso de un paciente desdentado total superior, rehabilitado en la consulta de implantología de la Clínica "Pedro Ortiz" del municipio Habana del Este en Ciudad de La Habana, Cuba, en el año 2009, mediante prótesis sobre implantes osteointegrados, técnica que se ha incorporado a la práctica estomatológica en Cuba como alternativa al tratamiento convencional en los pacientes desdentados totales. Se siguió un protocolo que comprendió una fase quirúrgica, procedimiento con o sin realización de colgajo y carga precoz o inmediata. Se presenta un paciente masculino de 56 años de edad, que acudió a la consulta multidisciplinaria, preocupado, porque se le habían elaborado tres prótesis en los últimos dos años y ninguna reunía los requisitos de retención que él necesitaba para sentirse seguro y cómodo con las mismas. El resultado final fue la satisfacción total del paciente, con el mejoramiento de la calidad estética y funcional.

  1. Parameter design and performance analysis of shift actuator for a two-speed automatic mechanical transmission for pure electric vehicles

    Directory of Open Access Journals (Sweden)

    Jianjun Hu

    2016-08-01

    Full Text Available Recent developments of pure electric vehicles have shown that pure electric vehicles equipped with two-speed or multi-speed gearbox possess higher energy efficiency by ensuring the drive motor operates at its peak performance range. This article presents the design, analysis, and control of a two-speed automatic mechanical transmission for pure electric vehicles. The shift actuator is based on a motor-controlled camshaft where a special geometric groove is machined, and the camshaft realizes the axial positions of the synchronizer sleeve for gear engaging, disengaging, and speed control of the drive motor. Based on the force analysis of shift process, the parameters of shift actuator and shift motor are designed. The drive motor’s torque control strategy before shifting, speed governing control strategy before engaging, shift actuator’s control strategy during gear engaging, and drive motor’s torque recovery strategy after shift process are proposed and implemented with a prototype. To validate the performance of the two-speed gearbox, a test bed was developed based on dSPACE that emulates various operation conditions. The experimental results indicate that the shift process with the proposed shift actuator and control strategy could be accomplished within 1 s under various operation conditions, with shift smoothness up to passenger car standard.

  2. Performance Investigation of Low-Speed Electric Vehicles%低速电动汽车的性能研究

    Institute of Scientific and Technical Information of China (English)

    吴正斌; 胡坚耀; 李程宇

    2015-01-01

    电动汽车是解决能源危机和环境污染的有效方法,但就目前情况来看,电动汽车大规模使用仍需时日。尽管如此,低速电动汽车目前已在中国低端电动汽车市场取得了成功。文章探讨了低速电动汽车的行驶特性、动态性能、电池性能和能量效率。通过底盘测功机实验测试与室外道路实验,分析了低速电动汽车的负载特性和过载特性,研究不同电池对低速电动车性价比的影响。虽然目前锂离子电池比铅酸电池成本更高,但实际应用中,锂离子电池效率更高、全寿命行驶距离更长。直流驱动电机有优秀的过载能力,但电机系统的低效率限制了低速电动汽车的整车能量效率。因此,开发低成本、高效率的电池及电机驱动系统是提高低速电动车性价比的有效途径。%Electric vehicle is an effective solution to the fossil fuel energy resource crisis and environmental pollution, but there is a wide gap between current market conditions and the anticipated products. However, low-speed electric vehicles have been commercially successful in the low-end performance electric vehicle market in China. In this paper, the ride characteristics, dynamic performance, battery performance, and power efficiency of a low-speed electric vehicle were examined. The vehicle characteristics were measured through dynamometer and road tests. The overload performance was also tested under the drive power more than 4 times the rated value. The effects of different batteries on the cost performance of low-speed electric vehicles were also analysed. Although the lithium-ion polymer battery is currently more costly than the lead-acid battery, the increased efifciency of this battery provides a more economical full-cycle lifetime driving distance for practical applications. The low power efifciency of the DC drive motor and its control system limit the general power efifciency of the low

  3. Performance evaluation of a micro turbo-expander for application in low-temperature solar electricity generation

    Institute of Scientific and Technical Information of China (English)

    Gang PEI; Yun-zhu LI; Jing LI; Jie JI

    2011-01-01

    A micro turbo-expander capable of high working speed was specially manufactured for use in an organic Rankine cycle (ORC). A series of tests were executed to examine the performance of the machine. In the experiment, the machine was tested under different inlet pressure conditions (0.2-0.5 MPa). Data such as the compressed air pressure, temperatures of the inlet and the outlet, rotational speed, and electric power generation were analyzed to discover underlying relationships. During the test,the rotational speed of the machine reached as high as 54 000 r/min, the peak value of the temperature drop between the inlet and the outlet reached 42 ℃, the maximum electric power generated by the motor-generator attached to the machine reached 630 W,and the efficiency of the machine reached 0.43.

  4. Controlling the ripple density and heights: a new way to improve the electrical performance of CVD-grown graphene

    Science.gov (United States)

    Park, Won-Hwa; Jo, Insu; Hong, Byung Hee; Cheong, Hyeonsik

    2016-05-01

    We report a new way to enhance the electrical performances of large area CVD-grown graphene through controlling the ripple density and heights after transfer onto SiO2/Si substrates by employing different cooling rates during fabrication. We find that graphene films prepared with a high cooling rate have reduced ripple density and heights and improved electrical characteristics such as higher electron/hole mobilities as well as reduced sheet resistance. The corresponding Raman analysis also shows a significant decrease of the defects when a higher cooling rate is employed. We suggest a model that explains the improved morphology of the graphene film obtained with higher cooling rates. From these points of view, we can suggest a new pathway toward a relatively lower density and heights of ripples in order to reduce the flexural phonon-electron scattering effect, leading to higher lateral carrier mobilities.We report a new way to enhance the electrical performances of large area CVD-grown graphene through controlling the ripple density and heights after transfer onto SiO2/Si substrates by employing different cooling rates during fabrication. We find that graphene films prepared with a high cooling rate have reduced ripple density and heights and improved electrical characteristics such as higher electron/hole mobilities as well as reduced sheet resistance. The corresponding Raman analysis also shows a significant decrease of the defects when a higher cooling rate is employed. We suggest a model that explains the improved morphology of the graphene film obtained with higher cooling rates. From these points of view, we can suggest a new pathway toward a relatively lower density and heights of ripples in order to reduce the flexural phonon-electron scattering effect, leading to higher lateral carrier mobilities. Electronic supplementary information (ESI) available: Reproducible data set. See DOI: 10.1039/c6nr00706f

  5. High speed electric motors based on high performance novel soft magnets

    Science.gov (United States)

    Silveyra, J. M.; Leary, A. M.; DeGeorge, V.; Simizu, S.; McHenry, M. E.

    2014-05-01

    Novel Co-based soft magnetic materials are presented as a potential substitute for electrical steels in high speed motors for current industry applications. The low losses, high permeabilities, and good mechanical strength of these materials enable application in high rotational speed induction machines. Here, we present a finite element analysis of Parallel Path Magnetic Technology rotating motors constructed with both silicon steel and Co-based nanocomposite. The later achieved a 70% size reduction and an 83% reduction on NdFeB magnet volume with respect to a similar Si-steel design.

  6. Electric utilities in the 1970's: financial practices and performance. Analysis report

    Energy Technology Data Exchange (ETDEWEB)

    Connor, E.G.

    1980-12-01

    Characteristics of financial factors that are controlled by regulatory bodies and which have a significant impact upon the financial condition of investor-owned electric utilities are explained. Specifically, the report emphasizes matters affecting a utility's cost of service such as: the composition of operating costs; normalization versus flow-through accounting (particularly where depreciation and the investment tax credit are concerned); the rate base; and construction work in progress and the related allowance for funds used during construction. Also reviewed is aggregate investor-owned utility financial data for the 1970 to 1977 period. A selected bibliography of 22 items is appended. 3 tables.

  7. Superior oblique surgery: when and how?

    Directory of Open Access Journals (Sweden)

    Taylan Şekeroğlu H

    2013-08-01

    Full Text Available Hande Taylan Şekeroğlu,1 Ali Sefik Sanac,1 Umut Arslan,2 Emin Cumhur Sener11Department of Ophthalmology, 2Department of Biostatistics, Hacettepe University Faculty of Medicine, Ankara, TurkeyBackground: The purpose of this paper is to review different types of superior oblique muscle surgeries, to describe the main areas in clinical practice where superior oblique surgery is required or preferred, and to discuss the preferred types of superior oblique surgery with respect to their clinical outcomes.Methods: A consecutive nonrandomized retrospective series of patients who had undergone superior oblique muscle surgery as a single procedure were enrolled in the study. The diagnosis, clinical features, preoperative and postoperative vertical deviations in primary position, type of surgery, complications, and clinical outcomes were reviewed. The primary outcome measures were the type of strabismus and the type of superior oblique muscle surgery. The secondary outcome measure was the results of the surgeries.Results: The review identified 40 (20 male, 20 female patients with a median age of 6 (2–45 years. Nineteen patients (47.5% had Brown syndrome, eleven (27.5% had fourth nerve palsy, and ten (25.0% had horizontal deviations with A pattern. The most commonly performed surgery was superior oblique tenotomy in 29 (72.5% patients followed by superior oblique tuck in eleven (27.5% patients. The amount of vertical deviation in the fourth nerve palsy and Brown syndrome groups (P = 0.01 for both and the amount of A pattern in the A pattern group were significantly reduced postoperatively (P = 0.02.Conclusion: Surgery for the superior oblique muscle requires experience and appropriate preoperative evaluation in view of its challenging nature. The main indications are Brown syndrome, fourth nerve palsy, and A pattern deviations. Superior oblique surgery may be effective in terms of pattern collapse and correction of vertical deviations in primary

  8. Electric drives

    CERN Document Server

    Boldea, Ion

    2005-01-01

    ENERGY CONVERSION IN ELECTRIC DRIVESElectric Drives: A DefinitionApplication Range of Electric DrivesEnergy Savings Pay Off RapidlyGlobal Energy Savings Through PEC DrivesMotor/Mechanical Load MatchMotion/Time Profile MatchLoad Dynamics and StabilityMultiquadrant OperationPerformance IndexesProblemsELECTRIC MOTORS FOR DRIVESElectric Drives: A Typical ConfigurationElectric Motors for DrivesDC Brush MotorsConventional AC MotorsPower Electronic Converter Dependent MotorsEnergy Conversion in Electric Motors/GeneratorsPOWER ELECTRONIC CONVERTERS (PECs) FOR DRIVESPower Electronic Switches (PESs)The

  9. Visual search performance is predicted by both prestimulus and poststimulus electrical brain activity

    NARCIS (Netherlands)

    van den Berg, Berry; Appelbaum, Lawrence G.; Clark, Kait; Lorist, Monicque M.; Woldorff, Marty G.

    2016-01-01

    An individual's performance on cognitive and perceptual tasks varies considerably across time and circumstances. We investigated neural mechanisms underlying such performance variability using regression-based analyses to examine trial-by-trial relationships between response times (RTs) and differen

  10. Electrical safety during transplantation.

    Science.gov (United States)

    Amicucci, G L; Di Lollo, L; Fiamingo, F; Mazzocchi, V; Platania, G; Ranieri, D; Razzano, R; Camin, G; Sebastiani, G; Gentile, P

    2010-01-01

    Technologic innovations enable management of medical equipment and power supply systems, with improvements that can affect the technical aspects, economics, and quality of medical service. Herein are outlined some technical guidelines, proposed by Istituto Superiore per la Prevenzione e la Sicurezza del Lavoro, for increasing the effectiveness of the power supply system and the safety of patients and surgeons in the operating room, with particular focus on transplantation. The dependence of diagnoses and therapies on operation of the electrical equipment can potentially cause great risk to patients. Moreover, it is possible that faulty electrical equipment could produce current that may flow through the patient. Because patients are particularly vulnerable when their natural protection is considerably decreased, as during transplantation or other surgery, power supply systems must operate with a high degree of reliability and quality to prevent risk, and must be designed to reduce hazards from direct and indirect contact. Reliability of the power supply system is closely related to the quality of the project, choice of materials, and management of the system (eg, quality and frequency of servicing). Among the proposed guidelines, other than normal referencing, are (1) adoption of a monitoring system to improve the quality of the electrical parameters in the operating room, (2) institution of emergency procedures for management of electrical faults, (3) a procedure for management of fires in the operating room, (4) and maintenance interventions and inspections of medical devices to maintain minimal requirements of safety and performance.

  11. Superior Na-Storage Performance of Low-Temperature-Synthesized Na3(VO(1-x)PO4)2F(1+2x) (0≤x≤1) Nanoparticles for Na-Ion Batteries.

    Science.gov (United States)

    Qi, Yuruo; Mu, Linqin; Zhao, Junmei; Hu, Yong-Sheng; Liu, Huizhou; Dai, Sheng

    2015-08-17

    Na-ion batteries are becoming comparable to Li-ion batteries because of their similar chemical characteristics and abundant sources of sodium. However, the materials production should be cost-effective in order to meet the demand for large-scale application. Here, a series of nanosized high-performance cathode materials, Na3(VO(1-x)PO4)2F(1+2x) (0≤x≤1), has been synthesized by a solvothermal low-temperature (60-120 °C) strategy without the use of organic ligands or surfactants. The as-synthesized Na3(VOPO4)2F nanoparticles show the best Na-storage performance reported so far in terms of both high rate capability (up to 10 C rate) and long cycle stability over 1200 cycles. To the best of our knowledge, the current developed synthetic strategy for Na3(VO(1-x)PO4)2F(1+2x) is by far one of the least expensive and energy-consuming methods, much superior to the conventional high-temperature solid-state method. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Influence of impurities on the performances of HIPS recycled from Waste Electric and Electronic Equipment (WEEE).

    Science.gov (United States)

    Perrin, Didier; Mantaux, Olivier; Ienny, Patrick; Léger, Romain; Dumon, Michel; Lopez-Cuesta, José-Marie

    2016-10-01

    In order to produce a high quality recycled material from real deposits of electric and electronic equipment, the rate of impurities in different blended grades of reclaimed materials has to be reduced. Setting up industrial recycling procedures requires to deal with the main types of polymers presents in WEEE (Waste Electric and Electronic Equipment), particularly High Impact Polystyrene (HIPS) as well as other styrenic polymers such as Acrylonitrile-Butadiene-Styrene (ABS), Polystyrene (PS) but also polyolefin which are present into WEEE deposit as Polypropylene (PP). The production of a substantial quantity of recycled materials implies to improve and master the compatibility of different HIPS grades. The influence of polymeric impurities has to be studied since automatic sorting techniques are not able to remove completely these fractions. Investigation of the influence of minor ABS, PS and PP polymer fractions as impurities has been done on microstructure and mechanical properties of HIPS using environmental scanning electron microscopy (ESEM) in order to determine the maximum tolerated rate for each of them into HIPS after sorting and recycling operations.

  13. Performance, cost and environmental assessment of gasification-based electricity in India: A preliminary analysis

    Science.gov (United States)

    Rani, Abha; Singh, Udayan; Jayant; Singh, Ajay K.; Sankar Mahapatra, Siba

    2017-07-01

    Coal gasification processes are crucial to decarbonisation in the power sector. While underground coal gasification (UCG) and integrated gasification combined cycle (IGCC) are different in terms of the site of gasification, they have considerable similarities in terms of the types of gasifiers used. Of course, UCG offers some additional advantages such as reduction of the fugitive methane emissions accompanying the coal mining process. Nevertheless, simulation of IGCC plants involving surface coal gasification is likely to give reasonable indication of the 3E (efficiency, economics and emissions) prospects of the gasification pathway towards electricity. This paper will aim at Estimating 3E impacts (efficiency, environment, economics) of gasification processes using simulation carried out in the Integrated Environmental Control Model (IECM) software framework. Key plant level controls which will be studied in this paper will be based on Indian financial regulations and operating costs which are specific to the country. Also, impacts of CO2 capture and storage (CCS) in these plants will be studied. The various parameters that can be studied are plant load factor, impact of coal quality and price, type of CO2 capture process, capital costs etc. It is hoped that relevant insights into electricity generation from gasification may be obtained with this paper.

  14. Electricity generating capacity and performance deterioration of a microbial fuel cell fed with beer brewery wastewater.

    Science.gov (United States)

    Köroğlu, Emre Oğuz; Özkaya, Bestamin; Denktaş, Cenk; Çakmakci, Mehmet

    2014-12-01

    This study focused on using beer brewery wastewater (BBW) to evaluate membrane concentrate disposal and production of electricity in microbial fuel cells. In the membrane treatment of BBW, the membrane permeate concentration was 570 ± 30 mg/L corresponding to a chemical oxygen demand (COD) removal efficiency of 75 ± 5%, and the flux values changed between 160 and 40 L/m(2)-h for all membrane runs. For electricity production from membrane concentrate, the highest current density in the microbial fuel cell (MFC) was observed to be 1950 mA/m(2) according to electrode surface area with 36% COD removal efficiency and 2.48% CE with 60% BBW membrane concentrate. The morphologies of the cation exchange membrane and the MFC deterioration were studied using a scanning electron microscope (SEM), attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA). A decrease in the thermal stability of the sulfonate (-SO3H) groups was demonstrated and morphological changes were detected in the SEM analysis. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  15. Fogging Control on LDPE/EVA Coextruded Films: Wettability Behavior and Its Correlation with Electric Performance

    Directory of Open Access Journals (Sweden)

    Miguel A. Waldo-Mendoza

    2017-02-01

    Full Text Available The transformation of fog at a non-visible water layer on a membrane of low-density polyethylene (LDPE and ethylene-vinyl acetate (EVA was evaluated. Nonionic surfactants of major demand in the polyolefin industry were studied. A kinetic study using a hot fog chamber showed that condensation is controlled by both the diffusion and permanency of the surfactant more than by the change of the surface energy developed by the wetting agents. The greatest permanency of the anti-fog effect of the LDPE/EVA surface was close to 3000 h. The contact angle results demonstrated the ability of the wetting agent to spread out to the surface. Complementarily, the migration of nonionic surfactants from the inside of the polymeric matrix to the surface was analyzed by Fourier transform infrared (FTIR microscopy. Additionally, electrical measurement on the anti-fogging membrane at alternating currents and at a sweep frequency was proposed to test the conductivity and wetting ability of nonionic surfactants. We proved that the amphiphilic molecules had the ability to increase the conductivity in the polyolefin membrane. A correlation between the bulk electrical conductivity and the permanency of the fogging control on the LDPE/EVA coextruded film was found.

  16. Experiment Investigation on Electrical and Thermal Performances of a Semitransparent Photovoltaic/Thermal System with Water Cooling

    Directory of Open Access Journals (Sweden)

    Guiqiang Li

    2014-01-01

    Full Text Available Different from the semitransparent building integrated photovoltaic/thermal (BIPV/T system with air cooling, the semitransparent BIPV/T system with water cooling is rare, especially based on the silicon solar cells. In this paper, a semitransparent photovoltaic/thermal system (SPV/T with water cooling was set up, which not only would provide the electrical power and hot water, but also could attain the natural illumination for the building. The PV efficiency, thermal efficiency, and exergy analysis were all adopted to illustrate the performance of SPV/T system. The results showed that the PV efficiency and the thermal efficiency were about 11.5% and 39.5%, respectively, on the typical sunny day. Furthermore, the PV and thermal efficiencies fit curves were made to demonstrate the SPV/T performance more comprehensively. The performance analysis indicated that the SPV/T system has a good application prospect for building.

  17. Electric Field Simulation and Effect of Different Solvent Ratios on the Performance of Single Electrospun PVDF/PEI Composite Film

    Directory of Open Access Journals (Sweden)

    Jin-gang Jiang

    2016-01-01

    Full Text Available On the basis of the finite element calculation theory of electric field, the electric field distribution in a representative electrospinning device is computed. The electric field structure of a needle-plate type electrospinning device was simulated by means of ANSYS software. And the vector distribution of the nozzle on the spinneret pipe was got. For the purpose of the analysis on the influence of different solvent ratios on the performance of a single electrospun PVDF/PEI composite film, polyvinylidene fluoride and polyetherimide with a mass ratio of 8/2 were dissolved in a mixed solvent. The mixed solvent is composed of N,N-dimethylformamide and tetrahydrofuran, added in different proportions. Through the electrostatic spinning technology, PVDF/PEI composite fiber membranes were prepared. Using scanning electron microscopy (SEM, X-ray diffraction (XRD, differential scanning calorimetry (DSC, and mechanical properties testing, the effects of tetrahydrofuran on the composite microstructure, crystallinity, and mechanical properties of the PVDF/PEI composite fiber membranes are discussed.

  18. Design Optimization and Performance of a Novel 6-Slot 5-Pole PMFSM with Hybrid Excitation for Hybrid Electric Vehicle

    Science.gov (United States)

    Sulaiman, Erwan; Kosaka, Takashi; Matsui, Nobuyuki

    With growing concerns over our environment, more and more people in automakers, governments and customers think that the electric drive becomes more attractive research. Since electric motors play an important role in both EVs and HEVs, it is a pressing need for researchers to develop advanced electric machines. As one of the candidates, permanent magnet flux switching machine (PMFSM) with additional coil excitation has several attractive features compared to interior permanent magnet synchronous machines (IPMSM) conventionally employed in HEV. The variable flux control capability and robust rotor structure make this machine becoming more attractive to apply for high speed motor drive system coupled with reduction gear. This paper presents an investigation into design possibility of 6-slot 5-pole PMFSM with hybrid excitation for traction drives in HEVs. An improved design is examined to gain a better performance in its maximum torque and power production. The final designed machine enables to keep much power density compared to existing IPMSM installed on the commercial SUV-HEV.

  19. Enhanced Absorption Performance of Carbon Nanostructure Based Metamaterials and Tuning Impedance Matching Behavior by an External AC Electric Field.

    Science.gov (United States)

    Gholipur, Reza; Khorshidi, Zahra; Bahari, Ali

    2017-04-12

    Metamaterials have surprisingly broadened the range of available practical applications in new devices such as shielding, microwave absorbing, and novel antennas. More research has been conducted related to tuning DNG frequency bands of ordered or disordered metamaterials, and far less research has focused on the importance of impedance matching behavior, with little effort and attention given to adjusting the magnitude of negative permittivity values. This is particularly important if devices deal with low-amplitude signals such as radio or TV antennas. The carbon/hafnium nickel oxide (C/Hf0.9Ni0.1Oy) nanocomposites with simultaneously negative permittivity and negative permeability, excellent metamaterial performance, and good impedance matching could become an efficient alternative for the ordered metamaterials in wave-transparent, microwave absorbing, and solar energy harvesting fields. In this study, we prepared C/Hf0.9Ni0.1Oy nanocomposites by the solvothermal method, and we clarified how the impedance matching and double-negative (DNG) behaviors of C/Hf0.9Ni0.1Oy can be tuned by an external AC electric field created by an electric quadrupole system. An external electric field allows for the alignment of the well-dispersed nanoparticles of carbon with long-range orientations order. We believe that this finding broadens our understanding of moderate conductive material-based random metamaterials (MCMRMs) and provides a novel strategy for replacing high-loss ordered or disordered metamaterials with MCMRMs.

  20. Influence of Electric Field Coupling Model on the Simulated Performances of a GaN Based Planar Nanodevice

    Directory of Open Access Journals (Sweden)

    K. Y. Xu

    2013-01-01

    Full Text Available The performances of a two-dimensional electron gas (2DEG based planar nanodevice are studied by a two-dimensional-three-dimensional (2D-3D combined model and an entirely 2D model. In both models, 2DEGs are depicted by 2D ensemble Monte Carlo (EMC method. However electric field distributions in the devices are obtained by self-consistently solving 2D and 3D Poisson equations for the 2D model and the 2D-3D model, respectively. Simulation results obtained by both models are almost the same at low bias while showing distinguished differences at high bias. The 2D model predicts larger output current and slightly higher threshold voltage of Gunn oscillations. Although the fundamental frequencies of current oscillations obtained by both models are similar, the deviation of wave shape from sinusoidal waveform obtained by the 2D model is more serious than that obtained by 2D-3D model. Moreover, results obtained by the 2D model are more sensitive both to the bias conditions and to the change of device parameters. Interestingly, a look-like second harmonic oscillation has been observed at DC bias. We contribute the origin of divergences in simulation results to the different coupling path of electric field in the two models. And the second-harmonic oscillations at DC bias should be the result of the appearance of concomitant oscillations beside the channel excited by strong electric-field effects.

  1. Numerical study on optical and electric-thermal performance for solar concentrating PV/T air system

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Hybrid photovoltaic/thermal(PV/T)system with solar concentrator is an effective way to improve solar energy conversion efficiency.In this work,a single-pass PV/T air system with a three-trough compound parabolic concentrator(CPC)of concentration ratio 2.0 is designed and the solar incident distributions at the solar cell surface are calculated by ray tracing method.Based on energy balance,the heat transfer models of all main components in this system are developed.The effects of some main designing and operational parameters on the electric-thermal performance of the system are analyzed. The results show that the solar radiation intensity can be higher than 1200 W/m 2 at most area of the cell surface.The temperature of the air and cell surface increases along the length of the system.Thus the system efficiency of the CPC is higher than that of the system without the CPC.The thermal efficiency, exergy and electrical efficiency of this CPC system increase with increasing of the air mass flow rate and the length of the system.With increasing packing fraction the electrical efficiency increases,but the thermal efficiency decreases.The exergy efficiency increases slightly with the packing fraction rising.The data obtained in this work are valuable for the design and operation for this kind of solar concentrating PV/T systems.

  2. Effect of electric field on the performance of soil electro-bioremediation with a periodic polarity reversal strategy.

    Science.gov (United States)

    Mena, E; Villaseñor, J; Cañizares, P; Rodrigo, M A

    2016-03-01

    In this work, it is studied the effect of the electric fields (within the range 0.0-1.5 V cm(-1)) on the performance of electrobioremediation with polarity reversal, using a bench scale plant with diesel-spiked kaolinite with 14-d long tests. Results obtained show that the periodic changes in the polarity of the electric field results in a more efficient treatment as compared with the single electro-bioremediation process, and it does not require the addition of a buffer to keep the pH within a suitable range. The soil heating was not very important and it did not cause a change in the temperature of the soil up to values incompatible with the life of microorganisms. Low values of water transported by the electro-osmosis process were attained with this strategy. After only 14 d of treatment, by using the highest electric field studied in this work (1.5 V cm(-1)), up to 35.40% of the diesel added at the beginning of the test was removed, value much higher than the 10.5% obtained by the single bioremediation technology in the same period.

  3. Numerical study on optical and electric-thermal performance for solar concentrating PV/T air system

    Institute of Scientific and Technical Information of China (English)

    SUN Jian; SHI MingHeng

    2009-01-01

    Hybrid photovoltaic/thermsl(PV/T)system with solar concentrator is an effective way to improve solar energy conversion efficiency.In this work,a single-pass PV/T sir system with a three-trough compound parabolic concentrator(CPC)of concentration ratio 2.0 is designed and the solar incident distributions at the solar cell surface are calculated by ray tracing method.Based on energy balance,the heat transfer models of all main components in this system are developed.The effects of some main designing and operational parameters on the electric-thermal performance of the system are analyzed.The results show that the solar radiation intensity can be higher than 1200 W/m~2 at most area of the cell surface.The temperature of the air and cell surface increases along the length of the system.Thus the system efficiency of the CPC is higher than that of the system without the CPC.The thermal efficiency,exergy and electrical efficiency of this CPC system increase with increasing of the air mass flow rate and the length of the system.With increasing packing fraction the electrical efficiency increases,but the thermal efficiency decreases.The exergy efficiency increases slightly with the packing fraction rising.The data obtained in this work are valuable for the design and operation for this kind of solar concentrating PV/T systems.

  4. Topological performance measures as surrogates for physical flow models for risk and vulnerability analysis for electric power systems.

    Science.gov (United States)

    LaRocca, Sarah; Johansson, Jonas; Hassel, Henrik; Guikema, Seth

    2015-04-01

    Critical infrastructure systems must be both robust and resilient in order to ensure the functioning of society. To improve the performance of such systems, we often use risk and vulnerability analysis to find and address system weaknesses. A critical component of such analyses is the ability to accurately determine the negative consequences of various types of failures in the system. Numerous mathematical and simulation models exist that can be used to this end. However, there are relatively few studies comparing the implications of using different modeling approaches in the context of comprehensive risk analysis of critical infrastructures. In this article, we suggest a classification of these models, which span from simple topologically-oriented models to advanced physical-flow-based models. Here, we focus on electric power systems and present a study aimed at understanding the tradeoffs between simplicity and fidelity in models used in the context of risk analysis. Specifically, the purpose of this article is to compare performance estimates achieved with a spectrum of approaches typically used for risk and vulnerability analysis of electric power systems and evaluate if more simplified topological measures can be combined using statistical methods to be used as a surrogate for physical flow models. The results of our work provide guidance as to appropriate models or combinations of models to use when analyzing large-scale critical infrastructure systems, where simulation times quickly become insurmountable when using more advanced models, severely limiting the extent of analyses that can be performed.

  5. Acceso a Recursos de Cómputo de Alto Rendimiento Mediante Correo Electrónico (An email-based platform for accessing High Performance Computing resources

    Directory of Open Access Journals (Sweden)

    Suilan Estévez Velarde

    2014-04-01

    Full Text Available Resumen El cómputo de alto rendimiento es una necesidad para el desarrollo de investigaciones con grandes volúmenes de datos. La creciente demanda de este tipo de resultados ha impulsado a varios centros de investigación a poner en funcionamiento recursos de cómputo de alto rendimiento. En Cuba no existe una solución definitiva que permita a todos los centros de investigación disponer de los recursos de cómputo necesarios para desarrollar sus proyectos. Este trabajo propone el empleo de un clúster de computadoras de la Universidad de Griffith a través de una interfaz basada en el correo electrónico. Esta solución permite disponer de recursos de cómputo de alto rendimiento sin necesidad de una alta conectividad. Como caso de estudio se analizan los resultados obtenidos en un proyecto de optimización global en grandes dimensiones desarrollado en la Universidad de La Habana. Para experimentos con un mes de duración (en una computadora estándar los resultados muestran que al utilizar el recurso de alto rendimiento es posible alcanzar un incremento en el rendimiento relativo superior al 1300%. Abstract: Research with large volumes of data usually require access to High Performance Computing. The increasing demand for this kind of research has led many institutions to develop their own computer clusters. However, in Cuba there is no definitive solution for the High Performance Computing requirements of institutions such as the University of Havana. The expenses of building a computer cluster disallows many institutions to have their own, while the low connectivity limits the use of international high performance computing services. This research presents an alternative solution based on the development of an email-based platform for accessing a computer cluster at Griffith University in Australia. This new communication interface has been successfully used on a Large Scale Optimization research project at the University of Havana

  6. Effect of electrical properties of glass electrodes on the performance of RPC detectors for the INO-ICAL experiment

    CERN Document Server

    Raveendrababu, K; Satyanarayana, B

    2016-01-01

    The India-based Neutrino Observatory (INO) collaboration has chosen glass Resistive Plate Chambers (RPCs) as the active detector elements for the Iron Calorimeter (ICAL) experiment. In the present work, we study the electrical properties such as bulk resistivity and relative permittivity of the glasses from two different manufacturers and compared the performances of RPCs built using these glasses. We conclude that the glass electrodes with larger bulk resistivy and permittivity are better suited for manufacturing RPCs for the ICAL experiment, as these detectors could be operated at lower bias currents and voltages, and produce better time resolutions compared to those built with glass electrodes of smaller bulk resistivity and permittivity.

  7. Electrical characterization of fluorinated benzothiadiazole based conjugated copolymer – a promising material for high-performance solar cells

    Directory of Open Access Journals (Sweden)

    J. Toušek

    2015-12-01

    Full Text Available Measurements of electrical conductivity, electron work function, carrier mobility of holes and the diffusion length of excitons were performed on samples of conjugated polymers relevant to polymer solar cells. A state of the art fluorinated benzothiadiazole based conjugated copolymer (PBDTTHD − DTBTff was studied and benchmarked against the reference polymer poly-3-hexylthiophene (P3HT. We employed, respectively, four electrode conductivity measurements, Kelvin probe work function measurements, carrier mobility using charge extraction by linearly increasing voltage (CELIV measurements and diffusion length determinaton using surface photovoltage measurements.

  8. Electrical characterization of fluorinated benzothiadiazole based conjugated copolymer – a promising material for high-performance solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Toušek, J., E-mail: jiri.tousek@mff.cuni.cz; Toušková, J.; Chomutová, R. [Charles University in Prague, Faculty of Mathematics and Physics, V Holešovičkách 2, 182 00 Prague 8 (Czech Republic); Remeš, Z.; Čermák, J. [Institute of Physics of the Academy of Sciences, Cukrovarnická 10, 162 53 Prague 6 (Czech Republic); Helgesen, M.; Carlé, J. E.; Krebs, F. C. [Department of Energy Conversion and Storage, Technical University of Denmark, Frederiksborgvej 399, DK-4000 Roskilde (Denmark)

    2015-12-15

    Measurements of electrical conductivity, electron work function, carrier mobility of holes and the diffusion length of excitons were performed on samples of conjugated polymers relevant to polymer solar cells. A state of the art fluorinated benzothiadiazole based conjugated copolymer (PBDT{sub THD} − DTBTff) was studied and benchmarked against the reference polymer poly-3-hexylthiophene (P3HT). We employed, respectively, four electrode conductivity measurements, Kelvin probe work function measurements, carrier mobility using charge extraction by linearly increasing voltage (CELIV) measurements and diffusion length determinaton using surface photovoltage measurements.

  9. Performance Optimization of Electrical Discharge Machining (Die Sinker for Al-6061 via Taguchi Approach

    Directory of Open Access Journals (Sweden)

    Muhammad Qaiser Saleem

    2015-04-01

    Full Text Available This paper parametrically optimizes the EDM (Electrical Discharge Machining process in die sinking mode for material removal rate, surface roughness and edge quality of aluminum alloy Al-6061. The effect of eight parameters namely discharge current, pulse on-time, pulse off-time, auxiliary current, working time, jump time distance, servo speed and work piece hardness are investigated. Taguchi's orthogonal array L18 is employed herein for experimentation. ANOVA (Analysis of Variance with F-ratio criterion at 95% confidence level is used for identification of significant parameters whereas SNR (Signal to Noise Ratio is used for determination of optimum levels. Optimization obtained for Al-6061 with parametric combination investigated herein is validated by the confirmation run.

  10. Interplay between electrical and mechanical domains in a high performance nonlinear energy harvester

    Science.gov (United States)

    Mallick, Dhiman; Amann, Andreas; Roy, Saibal

    2015-12-01

    This paper reports a comprehensive experimental characterization and modeling of a compact nonlinear energy harvester for low frequency applications. By exploiting the interaction between the electrical circuitry and the mechanical motion of the device, we are able to improve the power output over a large frequency range. This improvement is quantified using a new figure of merit based on a suitably defined ‘power integral (P f)’ for nonlinear vibrational energy harvesters. The developed device consists of beams with fixed-guided configuration which produce cubic monostable nonlinearity due to stretching strain. Using a high efficiency magnetic circuit a maximum output power of 488.47 μW across a resistive load of 4000 Ω under 0.5g input acceleration at 77 Hz frequency with 9.55 Hz of bandwidth is obtained. The dynamical characteristics of the device are theoretically reproduced and explained by a modified nonlinear Duffing oscillator model.

  11. Electrical properties and flux performance of composite ceramic hydrogen separation membranes

    DEFF Research Database (Denmark)

    Fish, J.S.; Ricote, Sandrine; O'Hayre, R.

    2015-01-01

    The electrical properties and hydrogen permeation flux behavior of the all-ceramic protonic/electronic conductor composite BaCe0.2Zr0.7Y0.1O3-δ/Sr0.95Ti0.9Nb0.1O3-δ (BCZY27/STN95: BS27) are evaluated. Conductivity and hydrogen permeability are examined as a function of phase volume ratios. Total...... with an effective medium approach incorporating a term for the heterojunctions between the two phases. Hydrogen fluxes of 0.004-0.008 μmol cm-2 s-1 are obtained for a 50 volume% STN95 membrane sample (1 mm thickness) at 600-800 °C using dry argon as a sweep gas. Upon adding palladium layers as catalysts more than...

  12. Effects of Deregulation and Vertical Unbundling on the Performance of China's Electricity Generation Sector†

    Science.gov (United States)

    Gao, Hang; Van Biesebroeck, Johannes

    2014-01-01

    The restructuring of the Chinese electricity sector in 2002 reshaped the market structure by vertically unbundling the dominant integrated firm and started the process of wholesale price liberalization. We estimate factor demands to study whether these reforms boosted productivity in the generation segment of the industry. Controlling explicitly for price‐heterogeneity across firms and unobservable productivity shocks, we find that the reforms are associated with reductions in labor and material use of 7 and 5 per cent, respectively. These effects only appear two years after the reforms and are robust to many specification checks. The absolute magnitudes of the estimated restructuring effects vary in intuitive ways by location, firm size or age, and for different definitions of restructured firms. PMID:27076686

  13. Microbial desalination cells for improved performance in wastewater treatment, electricity production, and desalination.

    Science.gov (United States)

    Luo, Haiping; Xu, Pei; Roane, Timberley M; Jenkins, Peter E; Ren, Zhiyong

    2012-02-01

    The low conductivity and alkalinity in municipal wastewater significantly limit power production from microbial fuel cells (MFCs). This study integrated desalination with wastewater treatment and electricity production in a microbial desalination cell (MDC) by utilizing the mutual benefits among the above functions. When using wastewater as the sole substrate, the power output from the MDC (8.01 W/m(3)) was four times higher than a control MFC without desalination function. In addition, the MDC removed 66% of the salts and improved COD removal by 52% and Coulombic efficiency by 131%. Desalination in MDCs improved wastewater characteristics by increasing the conductivity by 2.5 times and stabilizing anolyte pH, which therefore reduced system resistance and maintained microbial activity. Microbial community analysis revealed a more diverse anode microbial structure in the MDC than in the MFC. The results demonstrated that MDC can serve as a viable option for integrated wastewater treatment, energy production, and desalination.

  14. Optical, thermal, and electrical performance of low-CR solar arrays. [Concentration Ratio

    Science.gov (United States)

    French, E. P.; Mills, M. W.; Backovsky, Z.

    1983-01-01

    This paper describes the analysis and testing of a photovoltaic low-CR concentrator shaped like a truncated pyramid with an aperture of 0.5 m on a side and a geometric concentration ratio of six. The truncated base plane is covered by either silicon (Si) or gallium arsenide (GaAs) solar cells. Ray-trace analysis of the concentrator predicts a peak optical efficiency of 0.77, which falls off only gradually with pointing error. A coupled thermal-electrical analysis of the system shows that the moderately nonuniform illumination produced by the concentrator does not result in significant mismatch losses, provided the solar cells are connected in parallel groups. The results of ground tests involving a full-scale prototype concentrator conform well with theoretical predictions.

  15. Performance of ferrite fillers on electrical behavior of polymer nanocomposite electrolyte

    Science.gov (United States)

    Pandey, Kamlesh; Mauli Dwivedi, Mrigank; Singh, Markandey; Agrawal, S. L.

    2011-04-01

    Dispersal of nanofillers in polymer electrolytes have shown to improve the ionic properties of Polyethylene oxide (PEO)-based polymer electrolytes in recent times. The effects of different nanoferrite fillers (i.e., Al-Zn ferrite, Mg-Zn ferrite, and Zn ferrite) on the electrical transport properties have been studied here on the composite polymer electrolyte system. The interaction of salt/filler with electrolyte has been investigated by XRD studies. SEM image and infrared spectral studies give an indication of nanocomposite formation. In conductivity studies, all electrolyte systems are seen to follow universal power law. Composition dependence (with ferrite filler) gives the maximum conductivity in [93PEO-7NH4SCN]: X ferrite (where X = 2% in Al-Zn ferrite, 1% Mg-Zn ferrite, and 1% Zn ferrite) system.

  16. Improving electrical performance and bias stability of HfInZnO-TFT with optimizing the channel thickness

    Directory of Open Access Journals (Sweden)

    Jun Li

    2013-10-01

    Full Text Available RF magnetron sputtered HfInZnO film and atomic layer deposition (ALD Al2O3 film were employed for thin film transistors (TFTs as channel layer and gate insulator, respectively. To achieve HfInZnO-TFT with high performance and good bias stability, the thickness of HfInZnO active layer was optimized. The performance of HfInZnO-TFTs was found to be thickness dependent. As the HfInZnO active layer got thicker, the leakage current greatly increased from 1.73 × 10−12 to 2.54 × 10−8 A, the threshold voltage decreased from 7.4 to −4.7 V, while the subthreshold swing varied from 0.41 to 1.07 V/decade. Overall, the HfInZnO film showed superior performance, such as saturation mobility of 6.4 cm2/V s, threshold voltage of 4.2 V, subthreshold swing of 0.43 V/decade, on/off current ratio of 3 × 107 and Vth shift of 3.6 V under VGS = 10 V for 7200 s. The results demonstrate the possibility of fabricating TFTs using HfInZnO film as active layer and using ALD Al2O3 as gate insulator.

  17. The relationship between regional transport superiority and regional economic performance in Hainan%海南省区域交通优势度与经济发展关系

    Institute of Scientific and Technical Information of China (English)

    黄晓燕; 曹小曙; 李涛

    2011-01-01

    This study takes Hainan as a case and its 18 counties as basic unit for analysis.Choosing 3 indexes, including transport network density, proximity and accessibility, this paper constituted the spatial mathematical model to evaluate transport superiority degree firstly. Then, by utilizing GIS and IDW (Inverse Distance Weighted) technology, this paper studied spatial characteristic of transport network in Hainan. Moreover, we selected 4 aspects, i. e., total economic output and industrial structure, population and urbanization,living standards, transportation and the urban construction, 20 indexes all together and uses SPSS16.0 software with principal component analysis to quantitatively evaluate the level of economic development. By analysing spatial characteristic and summarizing spatial disciplinarian, this paper studied the relationship between regional transport superiority and economic performance in Hainan. The results showed that there were great differences in spatial distribution patterns between accessibility and economic development. But the spatial distribution patterns of transport superiority and regional economic performance are coherent, and there are positive relations between them, which showed an opposite spatial arrangement with geographic characteristics in Hainan.%以海南省为例,选取县级及以上城市为研究节点,采用交通网络密度、邻近度、通达性等指标,构建区域交通优势度综合评价的数理模型,运用GIS网络分析技术及IDW空间插值法定量分析海南省交通网络的地域空间特征.选取了经济总量和产业结构、人口与城市化、人民生活水平、交通与城市建设等4方面共20项主要的经济指标,运用SPSS软件用主成分分析法定量分析海南省区域经济差异及空间格局.通过对海南省各县市交通优势度及经济发展水平的特点及空问结构性规律进行分析,并比较二者间的联系,结果表明:海南省通达性空间格

  18. Re-Engineering a High Performance Electrical Series Elastic Actuator for Low-Cost Industrial Applications

    Directory of Open Access Journals (Sweden)

    Kenan Isik

    2017-01-01

    Full Text Available Cost is an important consideration when transferring a technology from research to industrial and educational use. In this paper, we introduce the design of an industrial grade series elastic actuator (SEA performed via re-engineering a research grade version of it. Cost-constrained design requires careful consideration of the key performance parameters for an optimal performance-to-cost component selection. To optimize the performance of the new design, we started by matching the capabilities of a high-performance SEA while cutting down its production cost significantly. Our posit was that performing a re-engineering design process on an existing high-end device will significantly reduce the cost without compromising the performance drastically. As a case study of design for manufacturability, we selected the University of Texas Series Elastic Actuator (UT-SEA, a high-performance SEA, for its high power density, compact design, high efficiency and high speed properties. We partnered with an industrial corporation in China to research the best pricing options and to exploit the retail and production facilities provided by the Shenzhen region. We succeeded in producing a low-cost industrial grade actuator at one-third of the cost of the original device by re-engineering the UT-SEA with commercial off-the-shelf components and reducing the number of custom-made parts. Subsequently, we conducted performance tests to demonstrate that the re-engineered product achieves the same high-performance specifications found in the original device. With this paper, we aim to raise awareness in the robotics community on the possibility of low-cost realization of low-volume, high performance, industrial grade research and education hardware.

  19. Investigating the technical, economic and environmental performance of electric vehicles in the real-world: A case study using electric scooters

    Science.gov (United States)

    Bishop, Justin D. K.; Doucette, Reed T.; Robinson, Daniel; Mills, Barnaby; McCulloch, Malcolm D.

    This work presents the findings of a small-scale electric scooter trial in Oxford, United Kingdom. The trial scooters were instrumented with global positioning satellite data loggers and energy meters to record their time of day usage and charging regimes. The scooters were most likely driving at 09:00, 12:45 and 17:15 and charging at 10:15-10:40. The electric scooter normalized mains-to-wheel energy use was 0.10 kWh km -1. The electric scooter total operating costs (electricity and battery replacement) of £0.045 km -1 is 24% greater than the best selling equivalent petrol motorcycle and 1.7 times lower than the best selling car. The electric scooter uses 0.45 MJ km -1, or 2.9 times and 6.1 times less than the petrol motorcycle and car, respectively. Further, the electric scooter can achieve zero carbon dioxide equivalent (greenhouse gas, GHG) emissions when electricity from renewable energy sources is used. In 2008, there were 247 000 motorcycles in the UK vehicle fleet of equivalent size to the trial scooter. Scaling up the electric vehicle fleet size accordingly would avoid 0.60 billion car or motorcycle kilometres and 54-110 kt associated GHG. The fleet would require 59 GWh, or 0.015% of total annual generation with a time-shifted, peak demand of 250 MW, or 0.44% of the 58 GW maximum national demand.

  20. Performances of a lithium-carbon ``lithium ion``battery for electric powered vehicle; Performances d`un accumulateur au lithium-carbone ``Lithium Ion`` pour vehicule electrique

    Energy Technology Data Exchange (ETDEWEB)

    Broussely, M.; Planchat, J.P.; Rigobert, G.; Virey, D.; Sarre, G. [SAFT, Advanced and Industrial Battery Group, 86 - Poitiers (France)

    1996-12-31

    The lithium battery, also called `lithium-carbon` or `lithium ion`, is today the most promising candidate that can reach the expected minimum traction performances of electric powered vehicles. Thanks to a more than 20 years experience on lithium generators and to a specific research program on lithium batteries, the SAFT company has developed a 100 Ah electrochemical system, and full-scale prototypes have been manufactured for this application. These prototypes use the Li{sub x}NiO{sub 2} lithiated graphite electrochemical pair and were tested in terms of their electrical performances. Energy characteristics of 125 Wh/kg and 265 Wh/dm{sup 3} could be obtained. The possibility of supplying a power greater than 200 W/kg, even at low temperature (-10 deg. C) has been demonstrated with these elements. A full battery set of about 20 kWh was built and its evaluation is in progress. It comprises the electronic control systems for the optimum power management during charge and output. (J.S.) 9 refs.

  1. T'ain't what you say, it's the way that you say it--left insula and inferior frontal cortex work in interaction with superior temporal regions to control the performance of vocal impersonations.

    Science.gov (United States)

    McGettigan, Carolyn; Eisner, Frank; Agnew, Zarinah K; Manly, Tom; Wisbey, Duncan; Scott, Sophie K

    2013-11-01

    Historically, the study of human identity perception has focused on faces, but the voice is also central to our expressions and experiences of identity [Belin, P., Fecteau, S., & Bedard, C. Thinking the voice: Neural correlates of voice perception. Trends in Cognitive Sciences, 8, 129-135, 2004]. Our voices are highly flexible and dynamic; talkers speak differently, depending on their health, emotional state, and the social setting, as well as extrinsic factors such as background noise. However, to date, there have been no studies of the neural correlates of identity modulation in speech production. In the current fMRI experiment, we measured the neural activity supporting controlled voice change in adult participants performing spoken impressions. We reveal that deliberate modulation of vocal identity recruits the left anterior insula and inferior frontal gyrus, supporting the planning of novel articulations. Bilateral sites in posterior superior temporal/inferior parietal cortex and a region in right middle/anterior STS showed greater responses during the emulation of specific vocal identities than for impressions of generic accents. Using functional connectivity analyses, we describe roles for these three sites in their interactions with the brain regions supporting speech planning and production. Our findings mark a significant step toward understanding the neural control of vocal identity, with wider implications for the cognitive control of voluntary motor acts.

  2. Solid State Digital Propulsion "Cluster Thrusters" For Small Satellites Using High Performance Electrically Controlled Extinguishable Solid Propellants (ECESP)

    Science.gov (United States)

    Sawka, Wayne N.; Katzakian, Arthur; Grix, Charles

    2005-01-01

    Electrically controlled extinguishable solid propellants (ESCSP) are capable of multiple ignitions, extinguishments and throttle control by the application of electrical power. Both core and end burning no moving parts ECESP grains/motors to three inches in diameter have now been tested. Ongoing research has led to a newer family of even higher performance ECESP providing up to 10% higher performance, manufacturing ease, and significantly higher electrical conduction. The high conductivity was not found to be desirable for larger motors; however it is ideal for downward scaling to micro and pico- propulsion applications with a web thickness of less than 0.125 inch/ diameter. As a solid solution propellant, this ECESP is molecularly uniform, having no granular structure. Because of this homogeneity and workable viscosity it can be directly cast into thin layers or vacuum cast into complex geometries. Both coaxial and grain stacks have been demonstrated. Combining individual propellant coaxial grains and/or grain stacks together form three-dimensional arrays yield modular cluster thrusters. Adoption of fabless manufacturing methods and standards from the electronics industry will provide custom, highly reproducible micro-propulsion arrays and clusters at low costs. These stack and cluster thruster designs provide a small footprint saving spacecraft surface area for solar panels and/or experiments. The simplicity of these thrusters will enable their broad use on micro-pico satellites for primary propulsion, ACS and formation flying applications. Larger spacecraft may find uses for ECESP thrusters on extended booms, on-orbit refueling, pneumatic actuators, and gas generators.

  3. A high performance, electric pump-fed LOX / RP propulsion system Project

    Data.gov (United States)

    National Aeronautics and Space Administration — To-date, the realization of small-scale, high-performance liquid bipropellant rocket engines has largely been limited by the inability to operate at high chamber...

  4. Direct ethanol fuel cell (DEFC): Electrical performances and reaction products distribution under operating conditions with different platinum-based anodes

    Energy Technology Data Exchange (ETDEWEB)

    Rousseau, S.; Coutanceau, C.; Lamy, C.; Leger, J.-M. [Laboratoire de Catalyse en Chimie Organique, -Equipe Electrocatalyse- UMR-CNRS 6503, Universite de Poitiers, 40 Avenue du Recteur Pineau, 86022 Poitiers Cedex (France)

    2006-07-14

    Ethanol electro-oxidation at different Pt-based electrodes was investigated in a single direct ethanol fuel cell (DEFC) in terms of reaction product distribution depending on the anode catalyst. In DEFC experiments, only three reaction products were detected using HPLC: acetaldehyde (AAL), acetic acid (AA) and CO{sub 2}. The addition of tin to platinum increases the activity of the catalyst by several order of magnitude and the electrical performance of the DEFC are greatly enhanced from a few mWcm{sup -2} to 30mWcm{sup -2} at 80{sup o}C, with Pt/C and Pt-Sn/C catalysts, respectively. Moreover, at Pt-Sn/C and Pt-Sn-Ru/C the formation of CO{sub 2} and AAL is lowered whereas the formation of AA is increased in comparison to what happens at a Pt/C catalyst. The addition of Ru to Pt-Sn only leads to enhance the electrical performance of the DEFC, i.e. the activity of the catalyst, but does not modify the product distribution. Very good stability in the open circuit voltage of the DEFC (close to 0.75V) was observed over a period of 2 weeks at 90{sup o}C, the cell undergoing start-run-stop cycles each day. Good stability under operating conditions at a given current density was also observed over 6h. (author)

  5. Superior-subordinate relations as organizational processes

    DEFF Research Database (Denmark)

    Asmuss, Birte; Aggerholm, Helle Kryger; Oshima, Sae

    Since the emergence of the practice turn in social sciences (Golsorkhi et al. 2010), studies have shown a number of institutionally relevant aspects as achievements across time and by means of various resources (human and non-human) (Taylor & van Every 2000, Cooren et al. 2006). Such a process view...... superior-subordinate relations in a specific institutionalized setting: performance appraisal interviews (PAIs). While one main task of PAIs is to manage and integrate organizational and employee performance (Fletcher, 2001:473), PAIs are also organizational practices where superior-subordinate relations...... are shaped, (re)confirmed and re-evaluated. This paper pursues the better understanding of the latter aspect by looking at one substantial and recurrent activity in PAIs: the evaluation of employee performance. One resource for doing the evaluation work is making assessments (e.g. Goodwin & Goodwin, 1987...

  6. Compositional influence on the electrical performance of zinc indium tin oxide transparent thin-film transistors

    Energy Technology Data Exchange (ETDEWEB)

    Marsal, A. [Dept Enginyeria Electronica and Center of Research in Nanoengineering, Universitat Politècnica Catalunya, Barcelona (Spain); Carreras, P. [Dept Física Aplicada i Òptica, Universitat de Barcelona, Barcelona (Spain); Puigdollers, J.; Voz, C.; Galindo, S.; Alcubilla, R. [Dept Enginyeria Electronica and Center of Research in Nanoengineering, Universitat Politècnica Catalunya, Barcelona (Spain); Bertomeu, J. [Dept Física Aplicada i Òptica, Universitat de Barcelona, Barcelona (Spain); Antony, A. [Dept Física Aplicada i Òptica, Universitat de Barcelona, Barcelona (Spain); Indian Institute of Technology, Bombay (India)

    2014-03-31

    In this work, zinc indium tin oxide layers with different compositions are used as the active layer of thin film transistors. This multicomponent transparent conductive oxide is gaining great interest due to its reduced content of the scarce indium element. Experimental data indicate that the incorporation of zinc promotes the creation of oxygen vacancies, which results in a higher free carrier density. In thin-film transistors this effect leads to a higher off current and threshold voltage values. The field-effect mobility is also strongly degraded, probably due to coulomb scattering by ionized defects. A post deposition annealing in air reduces the density of oxygen vacancies and improves the field-effect mobility by orders of magnitude. Finally, the electrical characteristics of the fabricated thin-film transistors have been analyzed to estimate the density of states in the gap of the active layers. These measurements reveal a clear peak located at 0.3 eV from the conduction band edge that could be attributed to oxygen vacancies. - Highlights: • Zinc promotes the creation of oxygen vacancies in zinc indium tin oxide transistors. • Post deposition annealing in air reduces the density of oxygen. • Density of states reveals a clear peak located at 0.3 eV from the conduction band.

  7. Efficacy of EMG/bioimpedance-triggered functional electrical stimulation on swallowing performance

    Directory of Open Access Journals (Sweden)

    Corinna Schultheiss

    2016-08-01

    Full Text Available In order to support swallowing, the efficacy of functional electrical stimulation for different stimulation settings of the submental musculature has been investigated. The stimulation was administrated at rest and synchronously to voluntary initiated swallows. The onset of a swallow was detected in real-time by a combined electromyography/ bioimpedance measurement at the neck in order to trigger the stimulation. The amplitude and speed of larynx elevation caused by the FES has been assessed by the observed change in bioimpedance whereas a reduction of bioimpedance corresponds to an increase in larynx elevation. Study results from 40 healthy subjects revealed that 73% of the subjects achieved a larger and faster larynx elevation during swallowing with triggered FES and therefor a better protection of their airways. However, we also observed a decrease in larynx elevation compared to normal swallowing in 11 out of the 40 subjects what might not benefit from such a treatment. The largest improvement of larynx elevation and speed during swallowing could be achieved with three stimulation channels formed by four electrodes in the submental region.

  8. The electrical performance of Ag Zn batteries for the Venus multi-probe mission

    Science.gov (United States)

    Palandati, C.

    1975-01-01

    An evaluation of 5 Ah and 21 Ah Silver-Zinc batteries was made to determine their suitability to meet the energy storage requirements of the bus vehicle, 3 small probes and large probe for the Venus multi-probe mission. The evaluation included a 4 Ah battery for the small probe, a 21 Ah battery for the large probe, one battery of each size for the bus vehicle power, a periodic cycling test on each size battery and a wet stand test of charged and discharged cells of both cell designs. The study on the probe batteries and bus vehicle batteries included both electrical and thermal simulation for the entire mission. The effects on silver migration and zinc penetration of the cellophane separators caused by the various test parameters were determined by visual and X-ray fluorescence analysis. The 5 Ah batteries supported the power requirements for the bus vehicle and small probe. The 21 Ah large probe battery supplied the required mission power. Both probe batteries delivered in excess of 132 percent of rated capacity at the completion of the mission simulation.

  9. Linking optical and electrical small amplitude perturbation techniques for dynamic performance characterization of dye solar cells.

    Science.gov (United States)

    Halme, Janne

    2011-07-21

    This paper unifies the analytical models used widely but thus far mostly separately for electrical and optical small amplitude perturbation measurements of nanostructured electrochemical dye solar cells (DSC): electrochemical impedance spectroscopy (EIS), intensity-modulated photocurrent spectroscopy (IMPS) and intensity-modulated photovoltage spectroscopy (IMVS). The models are linked by expressing the kinetic boundary condition used for solving the time-dependent continuity equation of electrons in IMPS and IMVS analysis in terms of the series and parallel impedance components found in the complete equivalent circuit impedance model of DSC. As a result, analytical expressions are derived for potentiostatic IMPS and galvanostatic IMVS transfer functions of complete DSCs that are applicable at any operating point along the solar cell current-voltage (IV) curve. In agreement with the theory, impedance spectrum calculated as a ratio of IMVS and IMPS transfer functions measured near the maximum power point matches exactly with the impedance spectrum measured directly with EIS. Consequently, both IMPS-IMVS and EIS yield equal estimates for the electron diffusion length. The role of the chemical capacitance of the nanostructured semiconductor photoelectrode in the interpretation of the so-called RC attenuation of the IMPS response is clarified, as well as the capacitive frequency dispersion in IMPS and IMVS. This journal is © the Owner Societies 2011

  10. A Review on Optimization of Process Parameters for Improving Performance in Electrical Discharge Machining

    Directory of Open Access Journals (Sweden)

    Viral B. Prajapati

    2014-02-01

    Full Text Available The correct selection of manufacturing conditions is one of the most important aspects to take into consideration in the majority of manufacturing processes and, particularly, in processes related to Electrical Discharge Machining (EDM. It is a capable of machining geometrically complex or hard material components, that are precise and difficult-to-machine such as heat treated tool steels, composites, super alloys, ceramics, carbides, heat resistant steels etc. being widely used in die and mold making industries, aerospace, aeronautics and nuclear industries. From the point of view of industrial applications, SS 410 is a very important material and that’s why for the purpose of experimentation SS 410 with copper electrode and EDM oil as dielectric has been used In the present work. I will take input parameter discharge current, pulse on time and pulse off time. Design of Experiment (DOE with full factorial design has been explored to produce 27 specimens on SS 410 by edm operation. MRR will be calculated from MRR equation and software available for it and then compare it. Collected data related to surface roughness have been utilized for optimization.

  11. Electrical performance analysis of HTS synchronous motor based on 3D FEM

    Science.gov (United States)

    Baik, S. K.; Kwon, Y. K.; Kim, H. M.; Lee, J. D.; Kim, Y. C.; Park, G. S.

    2010-11-01

    A 1-MW class superconducting motor with High-Temperature Superconducting (HTS) field coil is analyzed and tested. This machine is a prototype to make sure applicability aimed at generator and industrial motor applications such as blowers, pumps and compressors installed in large plants. This machine has the HTS field coil made of Bi-2223 HTS wire and the conventional copper armature (stator) coils cooled by water. The 1-MW class HTS motor is analyzed by 3D electromagnetic Finite Element Method (FEM) to get magnetic field distribution, self and mutual inductance, and so forth. Especially excitation voltage (Back EMF) is estimated by using the mutual inductance between armature and field coils and compared with experimental result. Open and short circuit tests were conducted in generator mode while a 1.1-MW rated induction machine was rotating the HTS machine. Electrical parameters such as mutual inductance and synchronous inductance are deduced from these tests and also compared with the analysis results from FEM.

  12. Performance Improvement of a Portable Electric Generator Using an Optimized Bio-Fuel Ratio in a Single Cylinder Two-Stroke Engine

    Directory of Open Access Journals (Sweden)

    Yamada Hiroaki

    2011-11-01

    Full Text Available The performance of an electrical generator using bio-fuel and gasoline blends of different composition as fuel in a single cylinder engine is presented. The effect of an optimized blend ratio of bio-fuel with gasoline on engine performance improvement and thereby on the electrical generator output is studied. Bio-fuels such as ethanol, butanol and methanol are blended with gasoline in different proportions and evaluated for performance. The effects of different bio-fuel/gasoline blending ratios are compared experimentally with that of the gasoline alone using the output power developed by the electric generator as the evaluation parameter. With a composition of 10% ethanol–gasoline, the engine performance is increased up to 6% and with a blending ratio of 20% butanol–gasoline the performance is increased up to 8% compared to the use of 100% gasoline. The investigations are performed on a portable generator used in palm tree harvesting applications.

  13. High performance self-excited reluctance generator for mini/micro hydro electric power generation

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, A.; Goel, S.K. [G.B.P.U.A. and T, Pantnagar (India). Dept. of Electrical Engineering

    2007-07-01

    Recent interest in the synchronous reluctance generator has increased because it offers the solution to the problems faced by induction generators while including almost all of the benefits of induction machines. This paper discussed the development of a mathematical model of a self excited synchronous reluctance generator using Park's transformation which can be used to obtain its performance by simulation. Almost all of the important performance parameters of reluctance machine depend on the saliency ratio .The paper focused on the fabrication, design and testing of an axially laminated anisotropic (ALA) rotor self-excited reluctance generator. The paper discussed SRM as a self-excited generator; maximization of saliency ratio; the assumptions made in obtaining the mathematical model of SRM; the laboratory machine; and results and discussion. It was concluded that compared to other rotor configurations, the ALA rotor with high saliency ratio performed better. 6 refs., 12 figs.

  14. A maintenance performance measurement framework that includesmaintenenace human factors: a case study from the electricity transmission industry

    Directory of Open Access Journals (Sweden)

    Peach, Rina

    2016-08-01

    Full Text Available Over the past two to three decades, maintenance management has undergone a paradigm shift; it is no longer seen as a necessary evil, but as an integral part of the business process that creates value for the organisation. The next step in the evolution of maintenance management is a maintenance performance measurement that includes human factors. The human factors in maintenance are well- known in the aviation industry, as it gained momentum in the early 1990s after a series of serious aviation accidents. Other industries, however, have been slow to integrate the human factor in their maintenance performance measurements. This paper discusses the results of a research project that investigated the use and importance of maintenance management performance measurements that focus specifically on human factors as part of the overall performance management system. From the research presented in this paper, ‘motivation’ and ‘competence’ were identified as the most important human performance factors in the maintenance of electricity transmission systems.

  15. The performance of integrated transconductance amplifiers as variable current sources for bio-electric impedance measurements.

    Science.gov (United States)

    Smith, D N

    1992-01-01

    Multiple applied current impedance measurement systems require numbers of current sources which operate simultaneously at the same frequency and within the same phase but at variable amplitudes. Investigations into the performance of some integrated operational transconductance amplifiers as variable current sources are described. Measurements of breakthrough, non-linearity and common-mode output levels for LM13600, NE5517 and CA3280 were carried out. The effects of such errors on the overall performance and stability of multiple current systems when driving floating loads are considered.

  16. Electricity mix and ecological assessments. Consequences of the choice of specific electricity mixes in analyses of the environmental performance of products and services; Strommix in Oekobilanzen. Auswirkungen der Strommodellwahl fuer Produkt- und Betriebs-Oekobilanzen

    Energy Technology Data Exchange (ETDEWEB)

    Menard, M.; Dones, R.; Gantner, U

    1998-12-01

    The study aims at analysing the methodological issues associated with the definition of electricity mixes and discussing the consequences of the choice of specific electricity mixes in analyses of the environmental performance of products and services, based on Life Cycle Assessment (LCA). This report has been designed as a guideline to support LCA practitioners in the systematic identification of the most appropriate electricity mixes for LCA applications. A detailed checklist has been developed for this purpose. It includes the following items: type of electricity supply (from the net, self production, direct contracts); voltage level; country/place of utilisation; year of utilisation; season/daytime of utilisation; import/export model; and, marginal vs. average approach. A few examples, utilising published LCA studies, illustrate the impacts of the insights gained in the present work. Although primarily aimed at applications in Switzerland, the main concepts, the modelling and parts of the information provided can also be applied to other European countries. In addition to the three models proposed earlier for the assessment of the Swiss yearly average electricity mix, a new model (M4) has been developed in the frame of the present task in order to take into account the conditions characteristic for Switzerland as a transit land for electricity trades between its neighbour countries. All existing electricity mix models as well as selected environmental inventories are described and compared in the report. As an example of results, the CO{sub 2} emissions calculated for the Swiss yearly electricity supply mix are relatively small (48 g/kWh with model M4, as compared with 497 g/kWh for the average UCPTE mix). Key information on the structure of electricity generation and trade in Europe is provided. The modelling of the electricity supply for most of the European countries is less sensitive to the choice of an electricity model than for Switzerland. Considering

  17. Long and short-term performance of a stabilized/solidified electric arc furnace dust.

    Science.gov (United States)

    Pereira, C Fernández; Galiano, Y Luna; Rodríguez-Piñero, M A; Parapar, J Vale

    2007-09-30

    The application of class F fly ash, cement and lime to the Stabilization/Solidification (S/S) of electric arc furnace dust containing hazardous metals such as Zn, Pb, Cd, and Cr is described. The aim of the study was to determine the influence of the setting conditions during the S/S treatment and to know the behaviour of an aged solidified and stabilized waste. In order to determine the efficiency attained by the S/S process, USEPA TCLP, and other leaching tests have been accomplished. In addition, the compressive strength of the solidified waste at different times has been determined. In order to study the influence of the environmental conditions in which setting occurs, experiments were carried out with samples of the same composition, under different setting conditions: laboratory environment, stove at a temperature of 40-60 degrees C and setting in a hermetically sealed plastic bag at room temperature. All the samples were subjected to the TCLP test at 28 days, and the metal content of the resulting leachates was analysed. The results show that in some cases the setting conditions of the mixtures have a noticeable influence on the characteristics of the leachate. The evolution with time of some S/S solids, one month after their manufacture and more than 9 years after that has also been evaluated, by means of their leaching behaviour. The results obtained in this work have shown, in all the laboratory cured samples that the leachate pH decrease in the course of time, and consequently the leaching behaviour is in general worse. This could be due to the carbonation of the S/S solid and the subsequent loss of alkalinity.

  18. Electrical performance analysis and economic evaluation of combined biomass cook stove thermoelectric (BITE) generator.

    Science.gov (United States)

    Lertsatitthanakorn, C

    2007-05-01

    The use of biomass cook stoves is widespread in the domestic sector of developing countries, but the stoves are not efficient. To advance the versatility of the cook stove, we investigated the feasibility of adding a commercial thermoelectric (TE) module made of bismuth-telluride based materials to the stove's side wall, thereby creating a thermoelectric generator system that utilizes a proportion of the stove's waste heat. The system, a biomass cook stove thermoelectric generator (BITE), consists of a commercial TE module (Taihuaxing model TEP1-1264-3.4), a metal sheet wall which acts as one side of the stove's structure and serves as the hot side of the TE module, and a rectangular fin heat sink at the cold side of the TE module. An experimental set-up was built to evaluate the conversion efficiency at various temperature ranges. The experimental set-up revealed that the electrical power output and the conversion efficiency depended on the temperature difference between the cold and hot sides of the TE module. At a temperature difference of approximately 150 degrees C, the unit achieved a power output of 2.4W. The conversion efficiency of 3.2% was enough to drive a low power incandescent light bulb or a small portable radio. A theoretical model approximated the power output at low temperature ranges. An economic analysis indicated that the payback period tends to be very short when compared with the cost of the same power supplied by batteries. Therefore, the generator design formulated here could be used in the domestic sector. The system is not intended to compete with primary power sources but serves adequately as an emergency or backup source of power.

  19. A State of the Art Review- Methods to Evaluate Electrical Performance of Composite Cross-arms and Composite-based Pylons

    DEFF Research Database (Denmark)

    Wang, Qian; Bak, Claus Leth; Silva, Filipe Miguel Faria da;

    2016-01-01

    A novel uni-body composite pylon has been proposed for 400 kV transmission lines with advantages of compacted size, friendly looking and cost competitiveness. As its configuration is quite different from the traditional lattice pylon, its electrical performance needs in-depth investigation...... and evaluation, for which electrical testing methods are essential. However, as research on composite-based pylons is still in initial stage, leaving international standards and theoretical analysis on this topic very limited, effective testing methods to evaluate the fully composite pylon’s electrical...... performance need to be studied. This paper sums up experience and key advances on testing methods to evaluate electrical performance of composite cross-arms and composite-based pylons. Based on state of the art review, several feasible testing methods that can be used to verify the feasibility of the novel...

  20. "Redstone Is Like Electricity": Children's Performative Representations in and around "Minecraft"

    Science.gov (United States)

    Dezuanni, Michael; O'Mara, Joanne; Beavis, Catherine

    2015-01-01

    This article investigates 8-and 9-year-old girls' use of the popular game "Minecraft" at home and school, particularly the ways in which they performatively "bring themselves into being" through talk and digital production in the social spaces of the classroom and within the game's multiplayer online world. We explore how the…

  1. A pilot scale electrical infrared dry-peeling system for tomatoes: design and performance evaluation

    Science.gov (United States)

    A pilot scale infrared dry-peeling system for tomatoes was designed and constructed. The system consisted of three major sections including the IR heating, vacuum, and pinch roller sections. The peeling performance of the system was examined under different operational conditions using tomatoes with...

  2. Optimization of the Mechanical and Electrical Performance of a Thermoelectric Module

    DEFF Research Database (Denmark)

    Sarhadi, Ali; Bjørk, Rasmus; Pryds, Nini

    2015-01-01

    Finite element (FE) simulation of a thermoelectric (TE) module was conducted to optimize its geometrical dimensions in terms of mechanical reliability and performance. The TE module consisted of bismuth telluride, nand p-type legs. The geometrical dimensions of the module, i.e. leg length and leg...

  3. The Role of Interaction Patterns with Hybrid Electric Vehicle Eco-Features for Drivers' Eco-Driving Performance.

    Science.gov (United States)

    Arend, Matthias G; Franke, Thomas

    2017-03-01

    The objective of the present research was to understand drivers' interaction patterns with hybrid electric vehicles' (HEV) eco-features (electric propulsion, regenerative braking, neutral mode) and their relationship to fuel efficiency and driver characteristics (technical system knowledge, eco-driving motivation). Eco-driving (driving behaviors performed to achieve higher fuel efficiency) has the potential to reduce CO2 emissions caused by road vehicles. Eco-driving in HEVs is particularly challenging due to the systems' dynamic energy flows. As a result, drivers are likely to show diverse eco-driving behaviors, depending on factors like knowledge and motivation. The eco-features represent an interface for the control of the systems' energy flows. A sample of 121 HEV drivers who had constantly logged their fuel consumption prior to the study participated in an online questionnaire. Drivers' interaction patterns with the eco-features were related to fuel efficiency. A common factor was identified in an exploratory factor analysis, characterizing the intensity of actively dealing with electric energy, which was also related to fuel efficiency. Driver characteristics were not related to this factor, yet they were significant predictors of fuel efficiency. From the perspective of user-energy interaction, the relationship of the aggregated factor to fuel efficiency emphasizes the central role of drivers' perception of and interaction with energy conversions in determining HEV eco-driving success. To arrive at an in-depth understanding of drivers' eco-driving behaviors that can guide interface design, authors of future research should be concerned with the psychological processes that underlie drivers' interaction patterns with eco-features.

  4. Performance appraisal of gas based electric power generation system using transfer function modelling

    Directory of Open Access Journals (Sweden)

    Chidozie Chukwuemeka Nwobi-Okoye

    2015-06-01

    Full Text Available Gas flaring for years has been a major environmental problem in many parts of the world. One way of solving the problem of gas flaring is to effectively utilize the abundant supply of gas for power generation. To effectively utilize gas for power generation requires highly efficient gas turbines and power facilities. Traditional methods of assessing the efficiency of power generation turbines do not take into consideration the stochastic nature of gas input and power output. This is because in a power generation system, as in any typical production system, there is generally marked variability in both input (gas and output (power of the process. This makes the determination of the relationship between input and output quite complex. This work utilized Box-Jenkins transfer function modelling technique, an integral part of statistical principle of time series analysis to model the efficiency of a gas power plant. This improved way of determining the efficiency of gas power generation facilities involves taking input–output data from a gas power generation process over a 10-year period and developing transfer function models of the process for the ten years, which are used as performance indicators. Based on the performance indicators obtained from the models, the results show that the efficiency of the gas power generation facility was best in the years 2007–2011 with a coefficient of performance of 0.002343345. Similarly, with a coefficient of performance of 0.002073617, plant performance/efficiency was worst in the years 2002–2006. Using the traditional method of calculating efficiency the values of 0.2613 and 0.2516 were obtained for years 2002–2006 and 2007–2011 respectively. The result is remarkable because given the state of the facilities, it correctly predicted the period of expected high system performance i.e. 2002–2006 period, but the traditional efficiency measurement method failed to do so. Ordinarily, using efficiency

  5. O impacto do desempenho das instituições de educação básica na qualidade do ensino superior El impacto del desempeño de las instituciones de educación básica en la calidad de la educación superior The impact of the performance of basic education institutions in the quality of higher education

    Directory of Open Access Journals (Sweden)

    Maria Cristina Nogueira Gramani

    2011-09-01

    Full Text Available Esta pesquisa analisou a eficiência educacional das Unidades Federativas (UF do Brasil, relacionando o desempenho das instituições de Educação Básica com a qualidade alcançada pelas instituições do ensino superior. Além disso, investigou-se em qual nível da Educação Básica devem alocar-se esforços para melhoria da eficiência educacional de cada UF. A eficiência educacional foi medida considerando a relação entre o índice de qualidade do Ensino Superior (produto e o desempenho da Educação Básica (insumos. O desempenho da educação básica levou em consideração o Índice de Desenvolvimento da Educação Básica (Ideb, já a qualidade do Ensino Superior foi determinada pelo Índice Geral de Cursos (IGC. Através de uma técnica denominada Data Envelopment Analysis, foram identificadas as UFs mais eficientes e as metas de melhoria para as menos eficientes. Os resultados indicaram ainda que, em geral, os anos iniciais do Ensino Fundamental merecem maior atenção por parte dos gestores e governantes.Este estudio analizó la eficiencia educacional de las Unidades de la Federación (UF en Brasil, relacionando el desempeño de las instituciones de la educación básica con la calidad de la educación superior. Además, se investigó en qué nivel de la educación básica se deben destinar los esfuerzos para mejorar la eficiencia educacional de cada estado. La eficiencia educacional se midió teniendo en cuenta la relación entre el índice de calidad de la enseñanza superior (producto y el rendimiento de la educación básica (insumos. El desempeño de la educación básica tuvo en cuenta el Índice de Desarrollo de la Educación Básica (IDEB, ya que la calidad de la educación superior fue determinada por el Índice General de Cursos (IGC. La técnica conocida como Análisis Exploratorio de Datos (DEA se utilizó para identificar la UF más eficiente y las metas de mejora para los menos eficientes. Los resultados también se

  6. Performance test results for the Eaton dc development power train in an electric test bed vehicle

    Science.gov (United States)

    Crumley, R. L.; Donaldson, M. R.

    1987-09-01

    This report presents the results of the tests performed on a direct current (dc) power train in a test bed vehicle developed by the Eaton Corporation for the U.S. Department of Energy (DOE). The tests were performed by EG and G Idaho, Inc. at the Idaho National Engineering Laboratory (INEL). The purpose of the INEL testing was to provide test results from which an evaluation of the performance capabilities of the Eaton dc power train could be made and compared with other vehicle propulsion systems. The planned tests were primarily oriented toward road testing, chassis dynamometer testing, and associated dynamometer coastdown tests for road loss determination. Range tests of the Eaton dc test bed vehicle using an ALCO 2200 lead acid battery pack, produced ranges of 97 km at 56 km/h (60 miles at 35 mph), 79 km at 72 km/h (49 miles at 45 mph), and 47 km at 88 km/h (29 miles at 55 mph). The corresponding net dc energy consumptions are 135 Wh/km (217 Wh/mile), 145 Wh/km (233 Wh/mile), and 178 Wh/km (287 Wh/mile). The energy consumption for the D-cycle test was 241 Wh/km (387 Wh/mile).

  7. Control and Performance Evaluation of Multiphase FSPM Motor in Low-Speed Region for Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Feng Yu

    2015-09-01

    Full Text Available The flux-switching permanent-magnet (FSPM motor has been viewed as a highly reliable machine with both armature windings and magnets on the stator. Owing to the high torque-production capability with low torque ripple, FSPM motors with a higher number of phases are potential candidates for traction applications in hybrid electric vehicles (HEVs. However, existing research has mostly focused on the principles and static performance of multiphase FSPM motors, and little attention has been paid to advanced control strategies. In this paper, the fully decoupled current control of a 36/34-pole nine-phase FSPM (NP-FSPM motor is developed and the performance under different operating conditions is investigated. The aim of the design is to alleviate cross coupling effects and unwanted low-order stator harmonic currents, to guarantee fast transient response and small steady-state error. In addition, its fault-tolerance is further elaborated. These features are very important in automotive applications where low torque pulsation, high fault-tolerant capability and high dynamic performance are of major importance. Firstly, the research status of multiphase FSPM motors is briefly reviewed. Secondly, the mathematical model in the dq reference frames and control strategies are presented. Then, the control and performance of the NP-FSPM motor are evaluated by using MATLAB/Simulink. Finally, experiments on an NP-FSPM motor prototype are carried out to validate the study.

  8. High-performance batteries for electric-vehicle propulsion and stationary energy storage. Progress report, October 1977--September 1978

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, P.A.; Barney, D.L.; Steunenberg, R.K.

    1978-11-01

    The research, development, and management activities of the programs at Argonne National Laboratory (ANL) and at industrial subcontractors' laboratories on high-temperature batteries during the period October 1977--September 1978 are reported. These batteries are being developed for electric-vehicle propulsion and for stationary-energy-storage applications. The present cells, which operate at 400 to 500/sup 0/C, are of a vertically oriented, prismatic design with one or more inner positive electrodes of FeS or FeS/sub 2/, facing electrodes of lithium--aluminum alloy, and molten LiCl--KCl electrolyte. During this fiscal year, cell and battery development work continued at ANL, Eagle--Picher Industries, Inc., the Energy Systems Group of Rockwell International, and Gould Inc. Related work was also in progress at the Carborundum Co., General Motors Research Laboratories, and various other organizations. A major event was the initiation of a subcontract with Eagle--Picher Industries to develop, design, and fabricate a 40-kWh battery (Mark IA) for testing in an electric van. Conceptual design studies on a 100-MWh stationary-energy-storage module were conducted as a joint effort between ANL and Rockwell International. A significant technical advance was the development of multiplate cells, which are capable of higher performance than bicells. 89 figures, 57 tables.

  9. Design study and performance analysis of 12S-14P field excitation flux switching motor for hybrid electric vehicle

    Science.gov (United States)

    Husin, Zhafir Aizat; Sulaiman, Erwan; Khan, Faisal; Mazlan, Mohamed Mubin Aizat; Othman, Syed Muhammad Naufal Syed

    2015-05-01

    This paper presents a new structure of 12slot-14pole field excitation flux switching motor (FEFSM) as an alternative candidate of non-Permanent Magnet (PM) machine for HEV drives. Design study, performance analysis and optimization of field excitation flux switching machine with non-rare-earth magnet for hybrid electric vehicle drive applications is done. The stator of projected machine consists of iron core made of electromagnetic steels, armature coils and field excitation coils as the only field mmf source. The rotor is consisted of only stack of iron and hence, it is reliable and appropriate for high speed operation. The design target is a machine with the maximum torque, power and power density, more than 210Nm, 123kW and 3.5kW/kg, respectively, which competes with interior permanent magnet synchronous machine used in existing hybrid electric vehicle. Some design feasibility studies on FEFSM based on 2D-FEA and deterministic optimization method will be applied to design the proposed machine.

  10. Map-Based Power-Split Strategy Design with Predictive Performance Optimization for Parallel Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Jixiang Fan

    2015-09-01

    Full Text Available In this paper, a map-based optimal energy management strategy is proposed to improve the consumption economy of a plug-in parallel hybrid electric vehicle. In the design of the maps, which provide both the torque split between engine and motor and the gear shift, not only the current vehicle speed and power demand, but also the optimality based on the predicted trajectory of vehicle dynamics are considered. To seek the optimality, the equivalent consumption, which trades off the fuel and electricity usages, is chosen as the cost function. Moreover, in order to decrease the model errors in the process of optimization conducted in the discrete time domain, the variational integrator is employed to calculate the evolution of the vehicle dynamics. To evaluate the proposed energy management strategy, the simulation results performed on a professional GT-Suit simulator are demonstrated and the comparison to a real-time optimization method is also given to show the advantage of the proposed off-line optimization approach.

  11. Avaliação do desempenho ambiental de uma instituição pública de ensino técnico e superior Environmental performance assessment of a public institution of technical and undergraduate education

    Directory of Open Access Journals (Sweden)

    Thomaz Sessegolo Marques de Almeida

    2012-01-01

    Full Text Available O objetivo deste artigo foi relatar um estudo de caso baseado em indicadores ambientais categóricos no qual foi avaliado o desempenho ambiental de uma instituição pública de ensino técnico e superior. A revisão incluiu a série de normas ISO 14000, o Prêmio Nacional de Qualidade em Saneamento (PNQS e o Ecoblock. O método usado foi adaptado do SBP, um conjunto de procedimentos para a mensuração do desempenho ambiental de uma atividade antrópica, que se vale de construtos latentes e indicadores categóricos que expliquem o desempenho. Os indicadores foram organizados em sete construtos. Segundo os avaliadores e o modelo, a instituição faz 56,7% do máximo possível em gestão ambiental. Os construtos mais carentes foram gestão de resíduos sólidos e poluição sonora. O resultado da avaliação pode ser usado para reformulação da política ambiental da instituição.This article reports a case study in which the environmental performance of a public institution of higher and technical education was evaluated, based on environmental indicators in spades. The following standards series were reviewed: ISO 14000, National Quality Award in Sanitation (PNQS and Ecoblock. The method was adapted from SBP, a set of procedures for measuring the environmental performance of an anthropic activity, composed by latent constructs and categorical indicators that explain the performance. The indicators were organized in seven constructs. According to the assessed respondents and the model, the institution reached 56.7% of the maximum possible in environmental management. Lower constructs were management of solid waste and noise pollution. The evaluation can be used for reshaping the environmental policy of the institution.

  12. 5-Hydroxytryptamine2A/2C receptors of nucleus raphe magnus and gigantocellularis/paragigantocellularis pars α reticular nuclei modulate the unconditioned fear-induced antinociception evoked by electrical stimulation of deep layers of the superior colliculus and dorsal periaqueductal grey matter.

    Science.gov (United States)

    de Oliveira, Ricardo; de Oliveira, Rithiele Cristina; Falconi-Sobrinho, Luiz Luciano; da Silva Soares, Raimundo; Coimbra, Norberto Cysne

    2017-01-01

    The electrical stimulation of the dorsolateral columns of the periaquedutal grey matter (dlPAG) or deep layers of the superior colliculus (dlSC) evokes defensive behaviours followed by an antinociceptive response. Monoaminergic brainstem reticular nuclei are suggested to comprise the endogenous pain modulatory system. The aim of the present work was to investigate the role played by 5-HT2 subfamily of serotonergic receptors of the nucleus raphe magnus (NRM) and the gigantocellularis/paragigantocellularis pars α reticular nuclei (Gi/PGiα) in the elaboration of instinctive fear-induced antinociception elicited by electrical stimulation of dlPAG or of dlSC. The nociceptive thresholds were measured by the tail-flick test in Wistar rats. The 5-HT2A/2C-serotonergic receptors antagonist ritanserin was microinjected at different concentrations (0.05, 0.5 and 5.0μg/0.2μL) either in Gi/PGiα or in NRM. The blockade of 5-HT2 receptors in both Gi/PGiα and NRM decreased the innate fear-induced antinociception elicited by electrical stimulation of the dlSC or the dlPAG. These findings indicate that serotonin is involved in the hypo-algesia induced by unconditioned fear-induced behavioural responses and the 5-HT2A/2C-serotonergic receptor subfamily in neurons situated in the Gi/PGiα complex and NRM are critically recruited in pain modulation during the panic-like emotional behaviour.

  13. Trailing edge devices to improve performance and increase lifetime of wind-electric water pumping systems

    Energy Technology Data Exchange (ETDEWEB)

    Vick, B.D.; Clark, R.N. [USDA-Agricultural Research Service, Bushland, TX (United States)

    1996-12-31

    Trailing edge flaps were applied to the blades of a 10 kW wind turbine used for water pumping to try to improve the performance and decrease the structural fatigue on the wind turbine. Most small wind turbines (10 kW and below) use furling (rotor turns out of wind similar to a mechanical windmill) to protect the wind turbine from overspeed during high winds. Some small wind turbines, however, do not furl soon enough to keep the wind turbine from being off line part of the time in moderately high wind speeds (10 - 16 m/s). As a result, the load is disconnected and no water is pumped at moderately high wind speeds. When the turbine is offline, the frequency increases rapidly often causing excessive vibration of the wind turbine and tower components. The furling wind speed could possibly be decreased by increasing the offset between the tower centerline and the rotor centerline, but would be a major and potentially expensive retrofit. Trailing edge flaps (TEF) were used as a quick inexpensive method to try to reduce the furling wind speed and increase the on time by reducing the rotor RPM. One TEF configuration improved the water pumping performance at moderately high wind speeds, but degraded the pumping performance at low wind speeds which resulted in little change in daily water volume. The other TEF configuration differed very little from the no flap configuration. Both TEF configurations however, reduced the rotor RPM in high wind conditions. The TEF, did not reduce the rotor RPM by lowering the furling wind speed as hoped, but apparently did so by increasing the drag which also reduced the volume of water pumped at the lower wind speeds. 6 refs., 9 figs.

  14. Performance assessment of electric power generations using an adaptive neural network algorithm and fuzzy DEA

    Energy Technology Data Exchange (ETDEWEB)

    Javaheri, Zahra

    2010-09-15

    Modeling, evaluating and analyzing performance of Iranian thermal power plants is the main goal of this study which is based on multi variant methods analysis. These methods include fuzzy DEA and adaptive neural network algorithm. At first, we determine indicators, then data is collected, next we obtained values of ranking and efficiency by Fuzzy DEA, Case study is thermal power plants In view of the fact that investment to establish on power plant is very high, and maintenance of power plant causes an expensive expenditure, moreover using fossil fuel effected environment hence optimum produce of current power plants is important.

  15. Relationship between the electric performance and the photoluminescence spectra of resonant tunnelling diodes

    Institute of Scientific and Technical Information of China (English)

    Zhang Xiao-Xin; Zeng Yi-Ping; Wang Xiao-Guang; Wang Bao-Qiang; Zhu Zhan-Ping

    2004-01-01

    Resonant tunnelling diodes with different structures were grown. Their photoluminescence spectra were investigated. By contrast, the luminescence in the quantum well is separated from that of other epilayers. The result is obtained that the exciton of the luminescence in the quantum well is partly come from the cap layer in the experiment.So the photoluminescence spectrum is closely related to the electron transport in the resonant tunnelling diode structure.This offers a method by which the important performance of resonant tunnelling diode could be forecast by analysing the integrated photoluminescence intensities.

  16. Um indicador para a avaliação do desempenho docente em instituições de ensino superior Un Indicador para la evaluación del desempeño docente en instituciones de enseñanza superior An indicator for the evaluation of the teaching performance in teaching institutions

    Directory of Open Access Journals (Sweden)

    Marcelo Embiruçu

    2010-12-01

    Full Text Available Este trabalho propõe a criação de um indicador de avaliação docente (IAD, objetivo e quantitativo, para ser utilizado como um instrumento da avaliação do desempenho de docentes em Instituições de Ensino Superior. Este indicador é aderente aos indicadores institucionais estabelecidos pelo Programa de Apoio a Planos de Reestruturação e Expansão das Universidades Federais (REUNI e procura também contemplar aspectos importantes para um indicador deste tipo, tais como robustez e exogenia, além de considerar ainda aspectos importantes da atuação universitária, tais como afastamentos, gestão acadêmica, atividades de extensão e produção científica qualificada, não contemplados na formulação original dos indicadores do REUNI. São incluídos também outros aspectos fundamentais, tais como a qualidade da graduação e a taxa de conclusão da pós-graduação. Assim, o índice faz uma avaliação docente bastante completa na medida em que considera todas as principais atividades docentes, quais sejam, ensino, pesquisa, extensão e gestão acadêmica, tanto na graduação quanto na pós-graduação. Os resultados apresentados mostram que o indicador é robusto e que o alcance das metas propostas é razoavelmente factível, podendo este ser utilizado como um instrumento útil para a política e a gestão acadêmica das instituições, de forma harmonizada com os programas e políticas de governo e de estado. Alguns parâmetros do indicador podem ser ajustados a fim de satisfazer metas e políticas específicas das instituições.Este trabajo propone la creación de un indicador de evaluación docente (IAD, objetivo y cuantitativo, con el objeto de utilizarlo como instrumento de evaluación del funcionamiento de profesores en instituciones de Enseñanza Superior. Este indicador se basa en Indicadores institucionales establecidos por el REUNI (Programa de Apoyo a Planes de Reestructuración y Expansión de las Universidades Federales

  17. The aerodynamic design and performance of the General Electric/NASA EEE fan. [Energy Efficient Engine

    Science.gov (United States)

    Sullivan, T. J.; Hager, R. D.

    1983-01-01

    The aerodynamic design and test results of the fan and quarter-stage component for the GE/NASA Energy Efficient Engine (EEE) are presented. The fan is a high bypass ratio, single-stage design having 32 part-span shrouded rotor blades, coupled with a unique quarter-stage arrangement that provides additional core-stream pressure ratio and particle separation. The fan produces a bypass pressure ratio of 1.65 at the exit of the low aspect ratio vane/frame and a core-stream pressure ratio of 1.67 at the entrance to the core frame struts. The full-scale fan vehicle was instrumented, assembled and tested as a component in November 1981. Performance mapping was conducted over a range of speeds and bypass ratios using individually-controlled bypass and core-stream discharge valves. The fan bypass and core-stream test data showed excellent results, with the fan exceeding all performance goals at the important engine operating conditions.

  18. Topological Performance Measures as Surrogates for Physical Flow Models for Risk and Vulnerability Analysis for Electric Power Systems

    CERN Document Server

    LaRocca, Sarah; Hassel, Henrik; Guikema, Seth

    2013-01-01

    Critical infrastructure systems must be both robust and resilient in order to ensure the functioning of society. To improve the performance of such systems, we often use risk and vulnerability analysis to find and address system weaknesses. A critical component of such analyses is the ability to accurately determine the negative consequences of various types of failures in the system. Numerous mathematical and simulation models exist which can be used to this end. However, there are relatively few studies comparing the implications of using different modeling approaches in the context of comprehensive risk analysis of critical infrastructures. Thus in this paper, we suggest a classification of these models, which span from simple topologically-oriented models to advanced physical flow-based models. Here, we focus on electric power systems and present a study aimed at understanding the tradeoffs between simplicity and fidelity in models used in the context of risk analysis. Specifically, the purpose of this pa...

  19. Improvement in the performance of inverted organic solar cell using electric field assisted spray deposited ZnO layer

    Science.gov (United States)

    Chaturvedi, Neha; Swami, Sanjay Kumar; Dutta, Viresh

    2015-06-01

    ZnO film was deposited using spray technique. The application of electric field (applying a DC voltage = 700V to the nozzle) during spray deposition provide compact nanostructured film of ZnO as compared to agglomerated ZnO film deposited using spray process. The ZnO film deposited after applying DC voltage during spray process showed good crystallinity as well as transmittance in the visible range. Use of this crystalline, compact layer of ZnO in inverted organic solar cell (ITO/ZnO/P3HT: PCBM/Ag) provide improved efficiency of 2.8% with JSC of 14.0 mA/cm2, VOC of 0.55V and FF of 36%. Thus the process remove the need of any post deposition treatment to improve the film quality as well as solar cell performance.

  20. Innovation Networks: the Contribution of Partnerships to Innovative Performance of Firms in the Brazilian Electrical-Electronics Industry

    Directory of Open Access Journals (Sweden)

    Silvye Ane Massaini

    2015-01-01

    Full Text Available Innovation networks have been identified in the literature as a way to complement firms’ innovative capabilities through collaboration with other partners. To provide empirical evidence for this assertion, this paper investigates the contribution of partners established in innovation networks for innovative performance of firms in the Brazilian electricalelectronics industry. For this purpose, we carried out an exploratory and descriptive survey among 185 companies. The data were analyzed using structural equation modeling (SEM. As the main findings, we observed that the establishment of collaborative relationships with customers, competitors and universities/research institutions can contribute to organizational and process innovation. However, despite obtaining some significant results concerning the contribution of different partners in the network, electrical-electronics industry companies also attach great importance to internal activities to develop their innovations.

  1. Experimental evaluation of high performance base course and road base asphalt concrete with electric arc furnace steel slags.

    Science.gov (United States)

    Pasetto, Marco; Baldo, Nicola

    2010-09-15

    The paper presents the results of a laboratory study aimed at verifying the use of two types of electric arc furnace (EAF) steel slags as substitutes for natural aggregates, in the composition of base course and road base asphalt concrete (BBAC) for flexible pavements. The trial was composed of a preliminary study of the chemical, physical, mechanical and leaching properties of the EAF steel slags, followed by the mix design and performance characterization of the bituminous mixes, through gyratory compaction tests, permanent deformation tests, stiffness modulus tests at various temperatures, fatigue tests and indirect tensile strength tests. All the mixtures with EAF slags presented better mechanical characteristics than those of the corresponding asphalts with natural aggregate and satisfied the requisites for acceptance in the Italian road sector technical standards, thus resulting as suitable for use in road construction.

  2. Measurements of Electric Performance and Impedance of a 75 Ah NMC Lithium Battery Module

    DEFF Research Database (Denmark)

    Jensen, Søren Højgaard; Engelbrecht, Kurt

    2012-01-01

    Detailed characterization of battery modules is necessary to construct reliable models that incorporate performance related aspects of the modules such as thermodynamics, electrochemical reaction kinetics and degradation mechanisms. Charge-discharge curves, temperature and battery impedance...... measurements can provide information about these aspects. Charge-discharge curves can be used to measure the battery open circuit voltage and the internal resistance. Temperature measurements provide information about the thermodynamic reactions and impedance spectra yield detailed information about...... the reaction kinetics. In this paper we present the measurement methods used to examine the internal resistance, the capacity and the impedance of a 75 Ah NMC battery module. In order to measure the impedance of the battery module and of the individual cells in the module, we combine the single sine technique...

  3. Wide temperature polyimide/ZrO2 nanodielectric capacitor film with excellent electrical performance

    Science.gov (United States)

    Zou, C.; Kushner, D.; Zhang, S.

    2011-02-01

    In this letter, wide temperature dielectric properties and corona resistance of Upilex-S® polyimide (PI) films filled with Zirconium dioxide (ZrO2) nanoparticles were investigated. ZrO2/PI nanodielectrics exhibited the stable dielectric properties, high energy density and high charge-discharge efficiency below 300 °C. Testing of corona resistance showed even a small amount of nanofillers can improve the lifetime of PI significantly. Scanning electron microscopy with x-ray microanalysis (SEM-EDS) analysis suggested the higher thermal conductivity and evaporation of ZrO2 nanoparticles may induce this improvement. These high performance features make polyimide nanocomposites attractive for high energy density capacitor applications at high temperature.

  4. Annealing effect on the structural and electrical performance of Mn-Co-Ni-O films

    Directory of Open Access Journals (Sweden)

    Fei Zhang

    2015-11-01

    Full Text Available Thin films of Mn1.95Co0.77Ni0.28O4are deposited on amorphous Al2O3 substrate by the magnetron sputtering method with the thickness of 6.5 μm. The effects of annealing treatment are studied on the film structural performance as well as the entropy of Mn-Co-Ni-O(MCNO films by annealed at 400 ∘C, 500 ∘C, 600 ∘C, 700 ∘C, 800 ∘C respectively. It shows that the crystallinity of the thin film is the best annealed at 700 ∘C and the entropy is the largest because the number of different kinds of ions belonging to the same element equals with each other. After 800 ∘C annealing, the film resistivity is the minimal with the maximal entropy which means the highest stability.

  5. Intrinsic electrical transport and performance projections of synthetic monolayer MoS2 devices

    Science.gov (United States)

    Smithe, Kirby K. H.; English, Chris D.; Suryavanshi, Saurabh V.; Pop, Eric

    2017-03-01

    We demonstrate monolayer (1L) MoS2 grown by chemical vapor deposition (CVD) with transport properties comparable to those of the best exfoliated 1L devices over a wide range of carrier densities (up to ˜1013 cm-2) and temperatures (80-500 K). Transfer length measurements decouple the intrinsic material mobility from the contact resistance, at practical carrier densities (>1012 cm-2). We demonstrate the highest current density reported to date (˜270 μA μm-1 or 44 MA cm-2) at 300 K for an 80 nm long device from CVD-grown 1L MoS2. Using simulations, we discuss what improvements of 1L MoS2 are still required to meet technology roadmap requirements for low power and high performance applications. Such results are an important step towards large-area electronics based on 1L semiconductors.

  6. Electrically evoked and voluntary maximal isometric tension in relation to dynamic muscle performance in elderly male subjects, aged 69 years.

    Science.gov (United States)

    Davies, C T; White, M J; Young, K

    1983-01-01

    The dynamic performance and electrically evoked mechanical properties of elderly triceps surae muscle have been investigated in 9 men, aged 69 yr. Dynamic performance consisted of cycling on a force bicycle and a vertical jump off two feet from a force platform. The results showed that the time to peak tension (TPT) and half relaxation time (1/2 RT) were significantly greater (p less than 0.001) by 30 ms and 22 ms and the supramaximal twitch (Pt) and tetanic (20 Hz-P020) tensions and maximal voluntary contraction (MVC) were less by 45 N (-33%), 708 N (-49%), and 899 N (-43%) in the elderly compared with young male control subjects. On the force platform, the height jumped (Ht), maximal force exerted (P), take-off velocity (VT), net impulse (NI) and peak power output (W) were less by 18.6 cm, 173 N, 0.9 ms-1, 52 Ns and 1120 w respectively. Similar differences of power, force and velocity were observed on the force bicycle. The reduction of W in the elderly was associated with the contractile characteristics of the leg muscle. The loss of contractile speed and capacity to to generate force in old people was reflected in their inability to develop power during the performance of a maximal vertical jump and cycling.

  7. Evaluation of the Effect of Operating Parameters on Thermal Performance of an Integrated Starter Generator in Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Moo-Yeon Lee

    2015-08-01

    Full Text Available The belt-driven-type integrated starter generator motor in a hybrid electric vehicle is vulnerable to thermal problems owing to its high output power and proximity to the engine. These problems may cause demagnetization and insulation breakdown, reducing the performance and durability of the motor. Hence, it is necessary to evaluate the thermal performance and enhance the cooling capacity of the belt-driven type Integrated Starter Generator. In this study, the internal temperature variations of the motor were investigated with respect to the operating parameters, particularly the rotation speed and environment temperature. At a maximum ambient temperature of 105 °C and rotation speed (motor design point of 4500 rpm, the coil of the motor was heated to approximately 189 °C in generating mode. The harsh conditions of the starting mode were analyzed by assuming that the motor operates during the start-up time at a maximum ambient temperature of 105 °C and rotation speed (motor design point of 800 rpm; the coil was heated to approximately 200 °C, which is close to the insulation temperature limit. The model for analyzing the thermal performance of the ISG was verified by comparing its results with those obtained through a generating-mode-based experiment

  8. Modeling the performance and cost of lithium-ion batteries for electric-drive vehicles.

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, P. A.

    2011-10-20

    This report details the Battery Performance and Cost model (BatPaC) developed at Argonne National Laboratory for lithium-ion battery packs used in automotive transportation. The model designs the battery for a specified power, energy, and type of vehicle battery. The cost of the designed battery is then calculated by accounting for every step in the lithium-ion battery manufacturing process. The assumed annual production level directly affects each process step. The total cost to the original equipment manufacturer calculated by the model includes the materials, manufacturing, and warranty costs for a battery produced in the year 2020 (in 2010 US$). At the time this report is written, this calculation is the only publically available model that performs a bottom-up lithium-ion battery design and cost calculation. Both the model and the report have been publically peer-reviewed by battery experts assembled by the U.S. Environmental Protection Agency. This report and accompanying model include changes made in response to the comments received during the peer-review. The purpose of the report is to document the equations and assumptions from which the model has been created. A user of the model will be able to recreate the calculations and perhaps more importantly, understand the driving forces for the results. Instructions for use and an illustration of model results are also presented. Almost every variable in the calculation may be changed by the user to represent a system different from the default values pre-entered into the program. The distinct advantage of using a bottom-up cost and design model is that the entire power-to-energy space may be traversed to examine the correlation between performance and cost. The BatPaC model accounts for the physical limitations of the electrochemical processes within the battery. Thus, unrealistic designs are penalized in energy density and cost, unlike cost models based on linear extrapolations. Additionally, the

  9. A State of the Art Review- Methods to Evaluate Electrical Performance of Composite Cross-arms and Composite-based Pylons

    DEFF Research Database (Denmark)

    Wang, Qian; Bak, Claus Leth; Silva, Filipe Miguel Faria da;

    2016-01-01

    performance need to be studied. This paper sums up experience and key advances on testing methods to evaluate electrical performance of composite cross-arms and composite-based pylons. Based on state of the art review, several feasible testing methods that can be used to verify the feasibility of the novel......A novel uni-body composite pylon has been proposed for 400 kV transmission lines with advantages of compacted size, friendly looking and cost competitiveness. As its configuration is quite different from the traditional lattice pylon, its electrical performance needs in-depth investigation...

  10. 羧基功能化和表面活性剂修饰对石墨烯电化学性能的影响%Superior Electrochemical Performance of Graphene via Carboxyl Functionalization and Surfactant Intercalation

    Institute of Scientific and Technical Information of China (English)

    于建华; 许丽丽; 朱倩倩; 王晓霞; 云茂金; 董立峰

    2016-01-01

    通过简单的两步溶液法对石墨烯进行羧基接枝和表面活性剂修饰,并研究其电化学性能。研究结果表明,与纯石墨烯(比电容50 F/g)相比,表面活性剂本身并不能有效提高石墨烯的比电容(45 F/g),羧基功能化可以将石墨烯的比电容提高至130 F/g。而羧基功能化和表面活性剂修饰双处理工艺能够将石墨烯的比电容提高到230 F/g,且经800次充放电循环后其比电容仍然具有95%的保持率,表明该材料具有良好的循环稳定性。因此,调控石墨烯的表面化学特性对提高其电化学性能具有重要的意义。%Superior capacitance of carboxyl functionalized and surfactant-intercalated graphene were prepared by a relatively simple with two-step solution-based processing technique. In comparison to pristine graphene, surface car-boxyl functionalization and surfactant intercalation can tailor its specific capacitance from 50 F/g to 230 F/g. Mean-while, the modified materials retain more than 95% of their capacitance after 800 charge-discharge cycles, demon-strating good cyclic stability. Surfactant itself cannot improve the performance of pristine graphene as graphene inter-calated with surfactant has a specific capacitance of 45 F/g, however, carboxyl groups can dramatically enhance spe-cific capacitance to 130 F/g. The excellent performance of functionalized graphene emphasizes the importance of con-trolling its surface chemistry.

  11. Efeito da fisioterapia no desempenho funcional do membro superior no pós-operatório de câncer de mama = Physical therapy effects on upper functional performance after breast cancer surgery

    OpenAIRE

    Rett,Mariana Tirolli

    2013-01-01

    Objetivo: Verificar o efeito da fisioterapia na amplitude de movimento (ADM) e no desempenho funcional do membro superior homolateral no pós-operatório para tratamento do câncer de mama e correlacionar estas variáveis Materiais e Métodos: Série de casos envolvendo mulheres submetidas à cirurgia unilateral para tratamento do câncer de mama, associado à linfadenectomia axilar. A ADM foi mensurada nos dois membros superiores através da goniometria, sendo o membro contralateral à cirurgia cons...

  12. Electrical performance of polymer ferroelectric capacitors fabricated on plastic substrate using transparent electrodes

    KAUST Repository

    Bhansali, Unnat Sampatraj

    2012-09-01

    Polymer-based flexible ferroelectric capacitors have been fabricated using a transparent conducting oxide (ITO) and a transparent conducting polymer (PEDOT:PSS). It is found that the polarization fatigue performance with transparent oxide electrodes exhibits a significant improvement over the polymer electrodes (20% vs 70% drop in polarization after 10 6 cycles). This result can be explained based on a charge injection model that is controlled by interfacial band-offsets, and subsequent pinning of ferroelectric domain walls by the injected carriers. Furthermore, the coercive field (E c) of devices with our polymer electrodes is nearly 40% lower than reported values with similar polymer electrodes. Surprisingly, this difference was found to be related to the dry etching process used to define the top electrodes, which is reported for the first time by this group. The temperature dependence of relative permittivity of both devices shows a typical first order ferroelectric-to-paraelectric phase transition, but with a reduced Curie temperature compared to reference devices fabricated on Pt. © 2012 Elsevier B.V. All rights reserved.

  13. Electrical performance of the InGaP solar cell irradiated with low energy electron beams

    Energy Technology Data Exchange (ETDEWEB)

    Okuno, Yasuki; Okuda, Shuichi; Kojima, Takeo; Oka, Takashi [Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai City, Osaka (Japan); Kawakita, Shirou; Imaizumi, Mitsuru; Kusawake, Hiroaki [Japan Aerospace Exploration Agency (JAXA), 2-1-1 Sengen, Tsukuba, Ibaraki (Japan)

    2015-06-15

    The investigation of the radiation degradation characteristics of InGaP space solar cells is important. In order to understand the mechanism of the degradation by radiation the samples of the InGaP solar cell were irradiated in vacuum and at ambient temperature with electron beams from a Cockcroft-Walton type accelerator at Osaka Prefecture University. The threshold energies for recoil were obtained by theoretical calculation. The energies and the fluences of the electron beams were from 60 to 400 keV and from 3 x 10{sup 14} to 3 x 10{sup 16} cm{sup -2}, respectively. The light-current-voltage measurements were performed. The degradation of Isc caused by the defects related to the phosphorus atoms was observed and the degradation was suppressed by irradiation at an energy higher than the threshold energy for recoiling Indium atoms. At an energy of 60 keV, where the recoil does not occur, the V{sub oc} was degraded. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. Flexural Capability of Patterned Transparent Conductive Substrate by Performing Electrical Measurements and Stress Simulations

    Directory of Open Access Journals (Sweden)

    Chang-Chun Lee

    2016-10-01

    Full Text Available The suitability of stacked thin films for next-generation display technology was analyzed based on their properties and geometrical designs to evaluate the mechanical reliability of transparent conducting thin films utilized in flexural displays. In general, the high bending stress induced by various operation conditions is a major concern regarding the mechanical reliability of indium–tin–oxide (ITO films deposited on polyethylene terephthalate (PET substrates; mechanical reliability is commonly used to estimate the flexibility of displays. However, the pattern effect is rarely investigated to estimate the mechanical reliability of ITO/PET films. Thus, this study examined the flexible content of patterned ITO/PET films with two different line widths by conducting bending tests and sheet resistance measurements. Moreover, a stress–strain simulation enabled by finite element analysis was performed on the patterned ITO/PET to explore the stress impact of stacked film structures under various levels of flexural load. Results show that the design of the ITO/PET film can be applied in developing mechanically reliable flexible electronics.

  15. No Influence of Transcutaneous Electrical Nerve Stimulation on Exercise-Induced Pain and 5-Km Cycling Time-Trial Performance

    Science.gov (United States)

    Hibbert, Andrew W.; Billaut, François; Varley, Matthew C.; Polman, Remco C. J.

    2017-01-01

    Introduction: Afferent information from exercising muscle contributes to the sensation of exercise-induced muscle pain. Transcutaneous electrical nerve stimulation (TENS) delivers low–voltage electrical currents to the skin, inhibiting nociceptive afferent information. The use of TENS in reducing perceptions of exercise-induced pain has not yet been fully explored. This study aimed to investigate the effect of TENS on exercise-induced muscle pain, pacing strategy, and performance during a 5-km cycling time trial (TT). Methods: On three separate occasions, in a single-blind, randomized, and cross-over design, 13 recreationally active participants underwent a 30-min TENS protocol, before performing a 5-km cycling TT. TENS was applied to the quadriceps prior to exercise under the following conditions; control (CONT), placebo with sham TENS application (PLAC), and an experimental condition with TENS application (TENS). Quadriceps fatigue was assessed with magnetic femoral nerve stimulation assessing changes in potentiated quadriceps twitch force at baseline, pre and post exercise. Subjective scores of exertion, affect and pain were taken every 1-km. Results: During TTs, application of TENS did not influence pain perceptions (P = 0.68, ηp2 = 0.03). There was no significant change in mean power (P = 0.16, ηp2 = 0.16) or TT duration (P = 0.17, ηp2 = 0.14), although effect sizes were large for these two variables. Changes in power output were not significant but showed moderate effect sizes at 500-m (ηp2 = 0.10) and 750-m (ηp2 = 0.10). Muscle recruitment as inferred by electromyography data was not significant, but showed large effect sizes at 250-m (ηp2 = 0.16), 500-m (ηp2 = 0.15), and 750-m (ηp2 = 0.14). This indicates a possible effect for TENS influencing performance up to 1-km. Discussion: These findings do not support the use of TENS to improve 5-km TT performance. PMID:28223939

  16. Hydrothermal Fabrication of Silver Nanowires-Silver Nanoparticles-Graphene Nanosheets Composites in Enhancing Electrical Conductive Performance of Electrically Conductive Adhesives

    Directory of Open Access Journals (Sweden)

    Hongru Ma

    2016-06-01

    Full Text Available Silver nanowires-silver nanoparticles-graphene nanosheets (AgNWs-AgNPs-GN hybrid nanomaterials were fabricated through a hydrothermal method by using glucose as a green reducing agent. The charge carriers of AgNWs-AgNPs-GN passed through defect regions in the GNs rapidly with the aid of the AgNW and AgNP building blocks, leading to high electrical conductivity of electrically conductive adhesives (ECA filled with AgNWs-AgNPs-GN. The morphologies of synthesized AgNWs-AgNPs-GN hybrid nanomaterials were characterized by field emission scanning electron microscope (FESEM, and high resolution transmission electron microscopy (HRTEM. X-ray diffraction (XRD and laser confocal micro-Raman spectroscopy were used to investigate the structure of AgNWs-AgNPs-GN. The resistance of cured ECAs was investigated by the four-probe method. The results indicated AgNWs-AgNPs-GN hybrid nanomaterials exhibited excellent electrical properties for decreasing the resistivity of electrically conductive adhesives (ECA. The resistivity of ECA was 3.01 × 10−4 Ω·cm when the content of the AgNWs-AgNPs-GN hybrid nanomaterial was 0.8 wt %.

  17. 75 FR 28542 - Superior Resource Advisory Committee

    Science.gov (United States)

    2010-05-21

    ... orient the new Superior Resource Advisory Committee members on their roles and responsibilities. DATES... of the roles and responsibilities of the Superior Resource Advisory Committee members; Election of... Forest Service Superior Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice...

  18. [The superior laryngeal nerve and the superior laryngeal artery].

    Science.gov (United States)

    Lang, J; Nachbaur, S; Fischer, K; Vogel, E

    1987-01-01

    Length, diameter and anastomoses of the nervus vagus and its ganglion inferius were measured 44 halved heads. On the average, 8.65 fiber bundles of the vagus nerve leave the retro-olivary area. In the area of the jugular foramen is the near superior ganglion of the 10th cranial nerve. In this area were found 1.48 (mean value) anastomoses with the 9th cranial nerve. 11.34 mm below the margo terminalis sigmoidea branches off the ramus internus of the accessory nerve which has a length of 9.75 mm. Further anastomoses with the 10th cranial nerve were found. The inferior ganglion of the 10th nerve had a length of 25.47 mm and a diameter of 3.46 mm. Five mm below the ganglion the 10th nerve had a width of 2.9 and a thickness of 1.5 mm. The mean length of the superior sympathetic ganglion was 26.6 mm, its width 7.2 and its thickness 3.4 mm. In nearly all specimens anastomoses of the superior sympathetic ganglion with the ansa cervicalis profunda and the inferior ganglion of the 10th cranial nerve were found. The superior laryngeal nerve branches off about 36 mm below the margo terminalis sigmoidea. The width of this nerve was 1.9 mm, its thickness 0.8 mm on the right and 1.0 mm on the left side. The division in the internal and external rami was found about 21 mm below its origin. Between the n. vagus and thyreohyoid membrane the ramus internus had a length of 64 mm, the length of external ramus between the vagal nerve and the inferior pharyngeal constrictor muscle was 89 mm. Its mean length below the thyreopharyngeal part was 10.7 mm, 8.6 branchlets to the cricothyroid muscle were counted. The superior laryngeal artery had its origin in 80% of cases in the superior thyroideal artery, in 6.8% this vessel was a branch of the external carotid artery. Its average outer diameter was 1.23 mm on the right side and 1.39 mm on the left. The length of this vessel between its origin and the thyreohyoid membrane was 34 mm. In 7% on the right side and in 13% on the left, the superior

  19. Macroscopic fibres of CNTs as electrodes for multifunctional electric double layer capacitors: from quantum capacitance to device performance

    Science.gov (United States)

    Senokos, E.; Reguero, V.; Palma, J.; Vilatela, J. J.; Marcilla, Rebeca

    2016-02-01

    In this work we present a combined electrochemical and mechanical study of mesoporous electrodes based on CNT fibres in the context of electric double layer capacitors. We show that through control of the synthetic and assembly processes of the fibres, it is possible to obtain an active material that combines a surface area of 250 m2 g-1, high electrical conductivity (3.5 × 105 S m-1) and mechanical properties in the high-performance range including toughness (35 J g-1) comparable to that of aramid fibre (e.g. Kevlar). These properties are a consequence of the predominant orientation of the CNTs, observed by wide- and small-angle X-ray diffraction, and to the exceptionally long CNT length on the millimetre scale. Cyclic voltammetry measurements in a three-electrode configuration and using 1-butyl-3-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (PYR14TFSI) ionic liquid electrolyte, show that the CNT fibres have a large quantum capacitance, evidenced by the near linear dependence of geometric capacitance (and conductivity) on potential bias. This reflects the low dimensionality of the CNT building blocks, which were purposely synthesised to have 1-5 layers and a high degree of graphitization. From the charge-discharge measurements of supercapacitor devices with symmetric CNT fibre electrodes we obtain power and energy densities as high as 58 kW kg-1 and 14 Wh kg-1, respectively. These record-high values for CNT fibre-based supercapacitors, are a consequence of the low equivalent series resistance due to the high conductivity of the fibres, the large contribution from quantum capacitance, and the wide stability window of the ionic liquid (3.5 V). Cycle life experiments demonstrate stable capacitance and energy retention over 10 000 cycles of charge-discharge at 3.5 V.In this work we present a combined electrochemical and mechanical study of mesoporous electrodes based on CNT fibres in the context of electric double layer capacitors. We show that through

  20. Exploring the word superiority effect using TVA

    DEFF Research Database (Denmark)

    Starrfelt, Randi

    Words are made of letters, and yet sometimes it is easier to identify a word than a single letter. This word superiority effect (WSE) has been observed when written stimuli are presented very briefly or degraded by visual noise. It is unclear, however, if this is due to a lower threshold...... for perception of words, or a higher speed of processing for words than letters. We have investigated the WSE using methods based on a Theory of Visual Attention. In an experiment using single stimuli (words or letters) presented centrally, we show that the classical WSE is specifically reflected in perceptual...... processing speed: words are simply processed faster than single letters. It is also clear from this experiment, that the word superiority effect can be observed at a large range of exposure durations, from the perceptual threshold to ceiling performance. Intriguingly, when multiple stimuli are presented...

  1. Impact of the cation composition on the electrical performance of solution-processed zinc tin oxide thin-film transistors.

    Science.gov (United States)

    Kim, Yoon Jang; Oh, Seungha; Yang, Bong Seob; Han, Sang Jin; Lee, Hong Woo; Kim, Hyuk Jin; Jeong, Jae Kyeong; Hwang, Cheol Seong; Kim, Hyeong Joon

    2014-08-27

    This study examined the structural, chemical, and electrical properties of solution-processed (Zn,Sn)O3 (ZTO) films with various Sn/[Zn+Sn] ratios for potential applications to large-area flat panel displays. ZTO films with a Zn-rich composition had a polycrystalline wurtzite structure. On the other hand, the Sn-rich ZTO films exhibited a rutile structure, where the Zn atom was speculated to replace the Sn site, thereby acting as an acceptor. In the intermediate composition regions (Sn/[Zn+Sn] ratio from 0.28 to 0.48), the ZTO films had an amorphous structure, even after annealing at 450 °C. The electrical transport properties and photobias stability of ZTO thin film transistors (TFTs) were also examined according to the Sn/[Zn+Sn] ratio. The optimal transport property of ZTO TFT was observed for the device with an amorphous structure at a Sn/[Zn+Sn] ratio of 0.48. The mobility, threshold voltage, subthreshold swing, and on/off current ratio were 4.3 cm(2)/(V s), 0 V, 0.4 V/decade, and 4.1 × 10(7), respectively. In contrast, the device performance for the ZTO TFTs with either a higher or lower Sn concentration suffered from low mobility and a high off-state current, respectively. The photoelectrical stress measurements showed that the photobias stability of the ZTO TFTs was improved substantially when the ZTO semiconducting films had a lower oxygen vacancy concentration and an amorphous structure. The relevant rationale is discussed based on the phototransition and subsequent migration mechanism from neutral to positively charged oxygen vacancies.

  2. Cooling Performance Characteristics of the Stack Thermal Management System for Fuel Cell Electric Vehicles under Actual Driving Conditions

    Directory of Open Access Journals (Sweden)

    Ho-Seong Lee

    2016-04-01

    Full Text Available The cooling performance of the stack radiator of a fuel cell electric vehicle was evaluated under various actual road driving conditions, such as highway and uphill travel. The thermal stability was then optimized, thereby ensuring stable operation of the stack thermal management system. The coolant inlet temperature of the radiator in the highway mode was lower than that associated with the uphill mode because the corresponding frontal air velocity was higher than obtained in the uphill mode. In both the highway and uphill modes, the coolant temperatures of the radiator, operated under actual road driving conditions, were lower than the allowable limit (80 °C; this is the maximum temperature at which stable operation of the stack thermal management system of the fuel cell electric vehicle could be maintained. Furthermore, under actual road driving conditions in uphill mode, the initial temperature difference (ITD between the coolant temperature and air temperature of the system was higher than that associated with the highway mode; this higher ITD occurred even though the thermal load of the system in uphill mode was greater than that corresponding to the highway mode. Since the coolant inlet temperature is expected to exceed the allowable limit (80 °C in uphill mode under higher ambient temperature with air conditioning system operation, the FEM design layout should be modified to improve the heat capacity. In addition, the overall volume of the stack cooling radiator is 52.2% higher than that of the present model and the coolant inlet temperature of the improved radiator is 22.7% lower than that of the present model.

  3. Absorber and gain chip optimization to improve performance from a passively modelocked electrically pumped vertical external cavity surface emitting laser

    Energy Technology Data Exchange (ETDEWEB)

    Zaugg, C. A., E-mail: zauggc@phys.ethz.ch; Mangold, M.; Pallmann, W. P.; Golling, M.; Tilma, B. W.; Keller, U. [Department of Physics, Institute for Quantum Electronics, ETH Zürich, 8093 Zürich (Switzerland); Gronenborn, S.; Moench, H.; Weichmann, U. [Philips Technologie GmbH Photonics Aachen, Steinbachstrasse 15, 52074 Aachen (Germany); Miller, M. [Philips Technologie GmbH U-L-M Photonics, Lise-Meitner-Strasse 13, 89081 Ulm (Germany)

    2014-03-24

    We present an electrically pumped vertical-external-cavity surface-emitting laser (EP-VECSEL) modelocked with a semiconductor saturable absorber mirror (SESAM) with significantly improved performance. In different cavity configurations, we present the shortest pulses (2.5 ps), highest average output power (53.2 mW), highest repetition rate (18.2 GHz), and highest peak power (4.7 W) to date. The simple and low-cost concept of EP-VECSELs is very attractive for mass-market applications such as optical communication and clocking. The improvements result from an optimized gain chip from Philips Technologie GmbH and a SESAM, specifically designed for EP-VECSELs. For the gain chip, we found a better trade-off between electrical and optical losses with an optimized doping scheme in the substrate to increase the average output power. Furthermore, the device's bottom contact diameter (60 μm) is smaller than the oxide aperture diameter (100 μm), which favors electro-optical conversion into a TEM{sub 00} mode. Compared to optically pumped VECSELs we have to increase the field enhancement in the active region of an EP-VECSEL which requires a SESAM with lower saturation fluence and higher modulation depth for modelocking. We therefore used a resonant quantum well SESAM with a 3.5-pair dielectric top-coating (SiN{sub x} and SiO{sub 2}) to enhance the field in the absorber at the lasing wavelength of 980 nm. The absorption bandedge at room temperature is detuned (965 nm) compared to the resonance (980 nm), which enables temperature-tuning of the modulation depth and saturation fluence from approximately 2.5% up to 15% and from 20 μJ/cm{sup 2} to 1.1 μJ/cm{sup 2}, respectively.

  4. Measurement of Electric Performance for UPS%不间断电源电气性能测试技术

    Institute of Scientific and Technical Information of China (English)

    李探元; 任宏; 王永岭

    2011-01-01

    通信电源是整个通信系统的"心脏"。交流不间断电源(UPS,Uninterruptible Power Supply)能够在交流输入突然切断时,通过后备电池继续保证高质量的交流供电。为了提高供电质量,保证通信网络的良好运行,必须对UPS电源设备的各种电气参数进行定期测量,以便及时了解设备的运行状况,调整不利于设备运行的参数。文中介绍了不间断电源(UPS)的工作原理,对其主要电气性能测试方法进行了详细论述。%The power supply is the heart of the communication system.Uninterrupted Power Supply(UPS) can provide AC power of high quality through backup battery,when the power is cut off suddenly.In order to improve the quality of power,electrical parameters of UPS should be periodically measured to make sure that the communication network runs in good condition.So that we can realize the running condition of the equipment in time and regulate the disadvantage parameters of the equipment.This article introduces the working principle of UPS and states particularly the measurements of main electrical performance.

  5. Absorber and gain chip optimization to improve performance from a passively modelocked electrically pumped vertical external cavity surface emitting laser

    Science.gov (United States)

    Zaugg, C. A.; Gronenborn, S.; Moench, H.; Mangold, M.; Miller, M.; Weichmann, U.; Pallmann, W. P.; Golling, M.; Tilma, B. W.; Keller, U.

    2014-03-01

    We present an electrically pumped vertical-external-cavity surface-emitting laser (EP-VECSEL) modelocked with a semiconductor saturable absorber mirror (SESAM) with significantly improved performance. In different cavity configurations, we present the shortest pulses (2.5 ps), highest average output power (53.2 mW), highest repetition rate (18.2 GHz), and highest peak power (4.7 W) to date. The simple and low-cost concept of EP-VECSELs is very attractive for mass-market applications such as optical communication and clocking. The improvements result from an optimized gain chip from Philips Technologie GmbH and a SESAM, specifically designed for EP-VECSELs. For the gain chip, we found a better trade-off between electrical and optical losses with an optimized doping scheme in the substrate to increase the average output power. Furthermore, the device's bottom contact diameter (60 μm) is smaller than the oxide aperture diameter (100 μm), which favors electro-optical conversion into a TEM00 mode. Compared to optically pumped VECSELs we have to increase the field enhancement in the active region of an EP-VECSEL which requires a SESAM with lower saturation fluence and higher modulation depth for modelocking. We therefore used a resonant quantum well SESAM with a 3.5-pair dielectric top-coating (SiNx and SiO2) to enhance the field in the absorber at the lasing wavelength of 980 nm. The absorption bandedge at room temperature is detuned (965 nm) compared to the resonance (980 nm), which enables temperature-tuning of the modulation depth and saturation fluence from approximately 2.5% up to 15% and from 20 μJ/cm2 to 1.1 μJ/cm2, respectively.

  6. A numerical method to enhance the performance of a cam-type electric motor-driven left ventricular assist device.

    Science.gov (United States)

    Huang, Huan; Yang, Ming; Lu, Cunyue; Xu, Liang; Zhuang, Xiaoqi; Meng, Fan

    2013-10-01

    Pulsatile left ventricular assist devices (LVADs) driven by electric motors have been widely accepted as a treatment of heart failure. Performance enhancement with computer assistance for this kind of LVAD has seldom been reported. In this article, a numerical method is proposed to assist the design of a cam-type pump. The method requires an integrated model of an LVAD system, consisting of a motor, a transmission mechanism, and a cardiovascular circulation. Performance indices, that is, outlet pressure, outlet flow, and pump efficiency, were used to select the best cam profile from six candidates. A prototype pump connected to a mock circulatory loop (MCL) was used to calibrate the friction coefficient of the cam groove and preliminarily evaluate modeling accuracy. In vitro experiments show that the mean outlet pressure and flow can be predicted with high accuracy by the model, and gross geometries of the measurements can also be reproduced. Simulation results demonstrate that as the total peripheral resistance (TPR) is fixed at 1.1 mm Hg.s/mL, the two-cycle 2/3-rise profile is the best. Compared with other profiles, the maximum increases of pressure and flow indices are 75 and 76%, respectively, and the maximum efficiency increase is over 51%. For different TPRs (0.5∼1.5 mm Hg.s/mL) and operation intervals (0.1∼0.4 s) in counterpulsation, the conclusion is also acceptable.

  7. Water-vortex-stabilized electric arc: III. Radial energy transport, determination of water-vapour-boundary and arc performance

    Science.gov (United States)

    Jenista, Jirí

    2003-12-01

    This paper is concerned with numerical modelling of an electric arc stabilized by a water vortex. The two-dimensional axisymmetric model presented includes the arc discharge area between the cathode and the outlet nozzle of the water plasma torch. The aims of the numerical simulations are: (1) to assess the influence of radial position of the water-vapour-boundary in the discharge chamber on arc performance and overall radial energy transport within the arc; (2) to determine the most probable mass flow rates and radii of the water-vapour-boundary in the discharge chamber for a prescribed current; (3) to demonstrate arc performance for two radiation models involved; and (4) to estimate validity of local thermodynamic equilibrium (LTE) conditions within the arc column. The rate of evaporation of water is calculated from the conduction and radiation heat fluxes at the water vapour surface for the specified mass flow rate. The behaviour of such an arc has been studied for a range of current 300-600 A. It is shown that changes of bulk magnitudes of different terms in the momentum and energy equations within the arc column as a function of arc radius enable us to reveal transitions of temperature and velocity fields from one steady state to a qualitatively different one. The best fit between experiment and numerical simulation for all currents exists for the mean arc radius ~3.3 mm. Deviations from LTE within the arc column are estimated with the criteria for kinetic equilibrium and spatial temperature gradients.

  8. Thermal Performance of Motor and Inverter in an Integrated Starter Generator System for a Hybrid Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Sung Chul Kim

    2013-11-01

    Full Text Available If the integrated starter generator (ISG motor and inverter operate under continuously high loading conditions, the system’s performance and durability will decrease and the heat dissipation requirements will increase. Therefore, in this study, we developed two cooling designs for the ISG motor and inverter, and then carried out both a model analysis and an experiment on the fluid flow and thermal characteristics of the system under various operating conditions. As the outdoor temperature increased from 25 °C to 95 °C, the coil temperature of the air-cooled motor increased by about 82 °C. Under the harsh-air condition of 95 °C, the coil of the air-cooled motor increased to a maximum temperature of about 158.5 °C. We also determined that the temperature of the metal-oxide-semiconductor field-effect transistor (MOSFET chip in the liquid-cooled inverter increased to a maximum temperature of about 96.8 °C under a coolant flow rate of 4 L/min and a coolant temperature of 65 °C. The observed thermal performance of the ISG motor and inverter using the proposed cooling structures was found to be sufficient for heat loads under various real driving conditions for a hybrid electric vehicle (HEV.

  9. Implicações e conquistas da atuação do intérprete de língua de sinais no Ensino Superior/Implications and conquests of the performance of the interpreter of language of signals in Superior Education

    Directory of Open Access Journals (Sweden)

    Vanessa Regina de Oliveira Martins

    2006-01-01

    Full Text Available A profissão do intérprete educacional tem ganhado espaço dentro da sala de aula. Salientamos que a notória presença e a maior visibilidade, atualmente, do intérprete de língua de sinais, é caracterizada no ensino superior. Isso em cumprimento da legislação que garante ao educando, com necessidades especiais, as mudanças necessárias para o atendimento e as adaptações pertinentes ao seu pleno acesso dentro da instituição de ensino. Nesse estudo observaremos a atuação do intérprete no ensino superior e as mudanças corporativas referentes à recepção e enquadramento deste novo profissional da educação. The profession as an educational interpreter has gained more and more ground in the classroom. It is important to emphasize that the greater current presence and visibility of the interpreter are specially noticed at the university-level education. That is due to the Brazilian legislation, which guarantees the necessary changes and adaptations for pupils with special needs, so that he or she can have full access to the educational facilities. This study aims to show the work of the interpreter in higher education and the corporate changes concerning the reception and the adjustments of this new professional in education.

  10. What are Millian Qualitative Superiorities?

    Directory of Open Access Journals (Sweden)

    Jonathan Riley

    2008-04-01

    Full Text Available In an article published in Prolegomena 2006, Christoph Schmidt-Petri has defended his interpretation and attacked mine of Mill’s idea that higher kinds of pleasure are superior in quality to lower kinds, regardless of quantity. Millian qualitative superiorities as I understand them are infinite superiorities. In this paper, I clarify my interpretation and show how Schmidt-Petri has misrepresented it and ignored the obvious textual support for it. As a result, he fails to understand how genuine Millian qualitative superiorities determine the novel structure of Mill’s pluralistic utilitarianism, in which a social code of justice that distributes equal rights and duties takes absolute priority over competing considerations. Schmidt-Petri’s own interpretation is a non-starter, because it does noteven recognize that Mill is talking about different kinds of pleasant feelings, such that the higher kinds are intrinsically more valuable than the lower. I conclude by outlining why my interpretation is free of any metaphysical commitment to the “essence” of pleasure.

  11. A escrita no Ensino Superior

    Directory of Open Access Journals (Sweden)

    Maria Conceição Pillon Christofoli

    2013-01-01

    Full Text Available http://dx.doi.org/10.5902/198464445865 O presente artigo trata de apresentar resultados oriundos de pesquisa realizada no Ensino Superior, enfocando a escrita em contextos universitários. Depoimentos por parte dos acadêmicos evidenciam certa resistência ao ato de escrever, o que acaba muitas vezes distanciando o sujeito da produção de um texto. Assim sendo, mesmo que parciais, os resultados até então analisados dão conta de que: pressuposto 1 – há ruptura da ideia de coerência entre o que pensamos, o que conseguimos escrever, o que entende nosso interlocutor; pressuposto 2 – a autocorreção de textos como exercício de pesquisa é imprescindível para a qualificação da escrita; pressuposto 3 – os diários de aula representam rico instrumento para a qualificação da escrita no Ensino Superior; pressuposto 4 – há necessidade de que o aluno do Ensino Superior escreva variados tipos de escrita, ainda que a universidade cumpra com seu papel, enfatizando a escrita acadêmica; pressuposto 5 – o trabalho com a escrita no Ensino Superior deve enfatizar os componentes básicos da expressão escrita: o código escrito e a composição da escrita. Palavras-chave: Escrita; Ensino Superior; formação de professores.

  12. [Superior vena cava syndrome--surgical solution--case report].

    Science.gov (United States)

    Galie, N; Vasile, R; Savu, C; Petreanu, C; Grigorie, V; Tabacu, E

    2010-01-01

    The patient of 52-year-old smoker was admitted in emergency with headaches, dyspnea, oedema and cyanosis of the cephalic extremity and of the superior members. This signs and symptoms suggest a superior vena cava sindrom. Thoracic CT scan shows the thrombosis of the superior vena cava and a tumor localized in the Bariety's Lodge of about 30/40 mm witch is around the right lateral wall of the traheea.This tumor is also tangent to the superior the superior vena cava. The patient was operated by total median sternotomy. By this approach we performed a complete excision of the mediastinal tumor mass. After that we effected a longitudinal cavotomy, we took out the endoluminal clot and we sutured the superior vena cava. The histological diagnosis of the mediastinal tumor was adenocarcinoma tubular-papillary moderately differentiated. The evolution post operative period was favorable the superior vena cava sindrom was a complet remission. The thoracic CT scan control after 9 months later didn't show a local relapse and blood flow was normally throw the superior vena cava.

  13. [Mitral surgery by superior biatrial septotomy].

    Science.gov (United States)

    Saade, A; Delepine, G; Lemaitre, C; Baehrel, B

    1995-01-01

    The superior biatrial septotomy approach consists of two semicircular right atrial and septal incisions joined at the superior end of the interatrial septum and extended across the dome of the left atrium, allowing exposure of the mitral valve by reflecting the ventricular side using stay sutures. From 1991 to 1993, 81 patients underwent mitral valve surgery by this technic. Mitral valve operation was combined with other cardiac procedures in 30 patients (37%) and was performed as a second operation in 21 patients (25.9%). Duration of cardiopulmonary bypass and aortic occlusion was not significantly different from that of patients operated via a conventional left atrial approach. The five hospital deaths (6.2%) were not related to this operative approach. Only 2 patients (3.3%) with preoperative in sinus rythm were discharged in atrial fibrillation after operation. In one patient (1.6%), atrioventricular block appeared at late follow-up. There were no cases of bleeding, atrioventricular nodal dysfunction or intra-atrial shunting related to the approach. This approach provides excellent exposure of the mitral valve even in unfavorable situations such as a small left atrium, dense adhesions from previous procedures or a previously implanted aortic prosthesis, without damage to various cardiac structures due to excessive traction. No retractor or vena cava repair are required. These data support a wide application of the superior biatrial septotomy approach in mitral valve surgery.

  14. Controllable electrical properties of metal-doped In2O3 nanowires for high-performance enhancement-mode transistors.

    Science.gov (United States)

    Zou, Xuming; Liu, Xingqiang; Wang, Chunlan; Jiang, Ying; Wang, Yong; Xiao, Xiangheng; Ho, Johnny C; Li, Jinchai; Jiang, Changzhong; Xiong, Qihua; Liao, Lei

    2013-01-22

    In recent years, In(2)O(3) nanowires (NWs) have been widely explored in many technological areas due to their excellent electrical and optical properties; however, most of these devices are based on In(2)O(3) NW field-effect transistors (FETs) operating in the depletion mode, which induces relatively higher power consumption and fancier circuit integration design. Here, n-type enhancement-mode In(2)O(3) NW FETs are successfully fabricated by doping different metal elements (Mg, Al, and Ga) in the NW channels. Importantly, the resulting threshold voltage can be effectively modulated through varying the metal (Mg, Ga, and Al) content in the NWs. A series of scaling effects in the mobility, transconductance, threshold voltage, and source-drain current with respect to the device channel length are also observed. Specifically, a small gate delay time (0.01 ns) and high on-current density (0.9 mA/μm) are obtained at 300 nm channel length. Furthermore, Mg-doped In(2)O(3) NWs are then employed to fabricate NW parallel array FETs with a high saturation current (0.5 mA), on/off ratio (>10(9)), and field-effect mobility (110 cm(2)/V·s), while the subthreshold slope and threshold voltage do not show any significant changes. All of these results indicate the great potency for metal-doped In(2)O(3) NWs used in the low-power, high-performance thin-film transistors.

  15. Electrical performance of multilayer MoS2 transistors on high-κ Al2O3 coated Si substrates

    Directory of Open Access Journals (Sweden)

    Tao Li

    2015-05-01

    Full Text Available The electrical performance of MoS2 can be engineered by introducing high-κ dielectrics, while the interactions between high-κ dielectrics and MoS2 need to be studied. In this study, multilayer MoS2 field-effect transistors (FETs with a back-gated configuration were fabricated on high-κ Al2O3 coated Si substrates. Compared with MoS2 FETs on SiO2, the field-effect mobility (μFE and subthreshold swing (SS were remarkably improved in MoS2/Al2O3/Si. The improved μFE was thought to result from the dielectric screening effect from high-κ Al2O3. When a HfO2 passivation layer was introduced on the top of MoS2/Al2O3/Si, the field-effect mobility was further enhanced, which was thought to be concerned with the decreased contact resistance between the metal and MoS2. Meanwhile, the interface trap density increased from 2.4×1012 eV−1cm−2 to 6.3×1012 eV−1cm−2. The increase of the off-state current and the negative shift of the threshold voltage may be related to the increase of interface traps.

  16. Influence of Different Rotor Teeth Shapes on the Performance of Flux Switching Permanent Magnet Machines Used for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Jing Zhao

    2014-12-01

    Full Text Available This paper investigated a 12-slot/11-pole flux switching permanent magnet (FSPM machine used for electric vehicles (EVs. Five novel rotor teeth shapes are proposed and researched to reduce the cogging torque and torque ripple of the FSPM machine. These rotor teeth shapes are notched teeth, stepped teeth, eccentric teeth, combination of notched and stepped teeth, and combination of notched and eccentric teeth. They are applied on the rotor and optimized, respectively. The influences of different rotor teeth shapes on cogging torque, torque ripple and electromagnetic torque are analyzed by the 2-D finite-element method (FEM. Then, the performance of FSPMs with different rotor teeth shapes are compared and evaluated comprehensively from the points of view of cogging torque, torque ripple, electromagnetic torque, flux linkage, back electromotive force (EMF, and so on. The results show that the presented rotor teeth shapes, especially the combination of stepped and notched teeth, can greatly reduce the cogging torque and torque ripple with only slight changes in the average electromagnetic torque.

  17. A High-Performance Control Method of Constant V/f-Controlled Induction Motor Drives for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Long Chen

    2014-01-01

    Full Text Available A three-phase induction motor used as a propulsion system for the electric vehicle (EV is a nonlinear, multi-input multi-output, and strong coupling system. For such a complicated model system with unmeasured and unavoidable disturbances, as well as parameter variations, the conventional vector control method cannot meet the demands of high-performance control. Therefore, a novel control strategy named least squares support vector machines (LSSVM inverse control is presented in the paper. Invertibility of the induction motor in the constant V/f control mode is proved to confirm its feasibility. The LSSVM inverse is composed of an LSSVM approximating the nonlinear mapping of the induction motor and two integrators. The inverse model of the constant V/f-controlled induction motor drive is obtained by using LSSVM, and then the optimal parameters of LSSVM are determined automatically by applying a modified particle swarm optimization (MPSO. Cascading the LSSVM inverse with the induction motor drive system, the pseudolinear system can be obtained. Thus, it is easy to design the closed-loop linear regulator. The simulation results verify the effectiveness of the proposed method.

  18. Performance indicators proposal for the government electric power distribution facilities in the Brazilian electric sector; Proposta de indicadores de desempenho as distribuidoras de energia federalizadas do setor eletrico brasileiro

    Energy Technology Data Exchange (ETDEWEB)

    Carregaro, Jose Carlos

    2003-07-01

    In this dissertation a set of indicators is proposed to the Centrais Eletricas Brasileiras S/A - ELETROBRAS, allowing the holding companies to attain the top position in the market, and a global vision of their performance. The methodology applied the definition of the performance indicators and the context, existing studies, and the indicators used by the Brazilian electric sector. It is expected that the proposed set of indicators be used by ELETROBRAS for a better planning and a more objective control of the holding companies performance, as well as an analysis of their administration strong and weak aspects.

  19. Water-vortex-stabilized electric arc: III. Radial energy transport, determination of water-vapour-boundary and arc performance

    Energy Technology Data Exchange (ETDEWEB)

    Jenista, Jiri [Institute of Plasma Physics ASCR, Za Slovankou 3, PO Box 17, Prague 8, 182 21 (Czech Republic)

    2003-12-07

    This paper is concerned with numerical modelling of an electric arc stabilized by a water vortex. The two-dimensional axisymmetric model presented includes the arc discharge area between the cathode and the outlet nozzle of the water plasma torch. The aims of the numerical simulations are: (1) to assess the influence of radial position of the water-vapour-boundary in the discharge chamber on arc performance and overall radial energy transport within the arc; (2) to determine the most probable mass flow rates and radii of the water-vapour-boundary in the discharge chamber for a prescribed current; (3) to demonstrate arc performance for two radiation models involved; and (4) to estimate validity of local thermodynamic equilibrium (LTE) conditions within the arc column. The rate of evaporation of water is calculated from the conduction and radiation heat fluxes at the water vapour surface for the specified mass flow rate. The behaviour of such an arc has been studied for a range of current 300-600 A. It is shown that changes of bulk magnitudes of different terms in the momentum and energy equations within the arc column as a function of arc radius enable us to reveal transitions of temperature and velocity fields from one steady state to a qualitatively different one. The best fit between experiment and numerical simulation for all currents exists for the mean arc radius {approx} 3.3 mm. Deviations from LTE within the arc column are estimated with the criteria for kinetic equilibrium and spatial temperature gradients.

  20. Acquired Brown Syndrome Treated With Traction of Superior Oblique Tendon.

    Science.gov (United States)

    Shin, Kwang Hoon; Paik, Hae Jung; Chi, Mijung

    2016-03-01

    Brown syndrome is a rare strabismic disease characterized by a limited elevation in adduction of the eye. The lengthening/weakening of superior oblique muscle is the main way of surgical intervention for this disease. A 7-year-old boy was diagnosed as having acquired Brown syndrome in his right eye after injury in his face. We experienced successful release of this Brown syndrome through mere pulling outward of superior oblique tendon during surgical exploration. We briefly discuss why this manipulation of superior oblique tendon that we performed was successful.