WorldWideScience

Sample records for device efficiency improvement

  1. Hall devices improve electric motor efficiency

    Science.gov (United States)

    Haeussermann, W.

    1979-01-01

    Efficiency of electric motors and generators is reduced by radial magnetic forces created by symmetric fields within device. Forces are sensed and counteracted by Hall devices on excitation or control windings. Hall generators directly measure and provide compensating control of anu asymmetry, eliminating additional measurements needed for calibration feedback control loop.

  2. Energy efficiency improvement of medical electric tools and devices

    Directory of Open Access Journals (Sweden)

    Meshkov Aleksandr S.

    2014-01-01

    Full Text Available With the ever-increasing volume of applications of various kinds of electric drives in all spheres of human activity, the issues in improving the efficiency of the electromechanical converters of electric energy, one of the most important components of the electric drive (ED, are becoming increasingly important. Such issues include reducing their weight and size, improving the functional characteristics of these devices to increase their operational life and reducing the cost of manufacture. Taking full advantage of these opportunities relates to the AC and DC single-phase commutator motor (SCM, which is widely used in regulated and high-speed motor drives in medical electric hand tools. The SCM is used in machinery where the load torque has a hyperbolic dependence on the rotational speed and the need to work with a large motor overload due to the “soft” mechanical characteristics of such motors.

  3. Evaluation of Efficiency Improvement in Vital Documentation Using RFID Devices.

    Science.gov (United States)

    Kimura, Eizen; Nakai, Miho; Ishihara, Ken

    2016-01-01

    We introduced medical devices with RFID tags and the terminal with RFID reader in our hospital. Time study was conducted in two phases. In phase I, nurses round as usual, and in phase II, the nurse round the ward with a terminal installed on a cart. This study concluded that RFID system shortens the time for vital sign documentation. However, deploying the terminals at every bedside did not contribute the more time reduction.

  4. Improving distillation method and device of tritiated water analysis for ultra high decontamination efficiency

    International Nuclear Information System (INIS)

    Fang, Hsin-Fa; Wang, Chu-Fang; Lin, Chien-Kung

    2015-01-01

    It is important that monitoring environmental tritiated water for understanding the contamination dispersion of the nuclear facilities. Tritium is a pure beta radionuclide which is usually measured by Liquid Scintillation Counting (LSC). The average energy of tritum beta is only 5.658 keV that makes the LSC counting of tritium easily be interfered by the beta emitted by other radionuclides. Environmental tritiated water samples usually need to be decontaminated by distillation for reducing the interference. After Fukushima Nucleaer Accident, the highest gross beta concentration of groundwater samples obtained around Fukushima Daiichi Nuclear Power Station is over 1,000,000 Bq/l. There is a need for a distillation with ultra-high decontamination efficiency for environmental tritiated water analysis. This study is intended to improve the heating temperature control for better sub-boiling distillation control and modify the height of the container of the air cooling distillation device for better fractional distillation effect. The DF of Cs-137 of the distillation may reach 450,000 which is far better than the prior study. The average loss rate of the improved method and device is about 2.6% which is better than the bias value listed in the ASTM D4107-08. It is proven that the modified air cooling distillation device can provide an easy-handling, water-saving, low cost and effective way of purifying water samples for higher beta radionuclides contaminated water samples which need ultra-high decontamination treatment. - Highlights: • The improvements of method and device make the decontaminatin factor (DF) of Cs-137 of distillation reach over 450,000. • The decontamination factor ( DF) value may be increased about 20 times by increasing the height of the container from 7 cm to 20 cm. • The device provides an easy-handling, water-saving, low cost, stable and effective way for the distillation of triated water analysis.

  5. On Improving the Energy Efficiency and Robustness of Position Tracking for Mobile Devices

    DEFF Research Database (Denmark)

    Kjærgaard, Mikkel Baun

    An important feature of a modern mobile device is that it can position itself and support remote position tracking. To be useful, such position tracking has to be energy-efficient to avoid having a major impact on the battery life of the mobile device. Furthermore, tracking has to robustly deliver...... of different mobile devices....

  6. Improving Device Efficiencies in Organic Photovoltaics through the Manipulation of Device Architectures and the Development of Low-Bandgap Materials

    Science.gov (United States)

    Rice, Andrew Hideo

    Over the past two decades, vast amounts of research have been conducted in the pursuit of suitable organic semiconductors to replace inorganic materials in electronic applications due to their advantages of being lightweight, flexible, and solution-processible. However, before organic photovoltaics (OPVs) can be truly competitive and commercially viable, their efficiencies must be improved significantly. In this examination, we pursue higher efficiency OPVs in two different ways. Our attempts focus on 1) altering the microstructure of devices to improve charge dissociation, charge transport, and our understanding of how these devices function, and 2) tailoring materials to achieve optimal band gaps and energy levels for use in organic electronics. First, we demonstrate how the vertical morphology of bulk heterojunction (BHJ) solar cells, with an active layer consisting of self-assembled poly(3-hexylthiophene) (P3HT) nanowires and (6,6)-phenyl C61-butyric acid methyl ester (PCBM), can be beneficially influenced. Most device fabrication routes using similar materials employ an annealing step to influence active layer morphology, but this process can create an unfavorable phase migration where P3HT is driven toward the cathode. In contrast, we demonstrate devices that exhibit an increase in relative fullerene concentration at the top of the active layer by introducing the donor phase as a solid nanowire in the active layer solution and altering the pre-spin drying time. X-ray photoelectron spectroscopy (XPS) and conductive and photoconductive atomic force microscopy (cAFM and pcAFM) provide detailed information about how the surface of the active layer can be influenced; this is done by tracking the concentration and alignment of P3HT and PCBM domains. Using this new procedure, devices are made with power conversion efficiencies surpassing 2%. Additionally, we show that nanowires grown in the presence of the fullerene perform differently than those that are grown and

  7. IMPROVING THE EFFICIENCY OF SPRAY TYPE DEVICES WHEN SOLVING PROBLEMS IN INDUSTRIAL ECOLOGY

    Directory of Open Access Journals (Sweden)

    S. Iu. Panov

    2014-01-01

    Full Text Available Summary. This carried out work is aimed enhancing the efficiency of the spray scrubber by combining processes and improving hydraulic conditions in the device. The problem of treating waste gases is often characterized by unique features and the significant factor that makes it difficult to find a solution to the problem of treatment is the low and/or variable concentration of the pollutant. With a removal efficiency of up to 98 %, wet treatment technology in scrubber type devices is the only practical method advantageous to the treatment of waste gases. The set objective is solved by developing a two-stage treatment system for pyrolysis gas based on ejector scrubbers. Their advantage - a central nozzle supply that allows the scrubber to operate on the principle of an ejector pump. A drift eliminator of the developed device is located on the case unit and a chain is suspended from a clamp mounted on the lower part of the tube neck by pins and two detachable joints. The operation of the scrubber was checked in compliance with the absorption gas treatment of sulfur dioxide. A chemical sorbent, calcium carbonate which is produced as a by-product in the manufacture of nitroammophos at JSC “Minudobrenia” factory is used. Preliminary results indicate that the stiochiometric inlet ratio of Ca/S equals about 2.0 and SO2 emissions reduce by 80-90 %, significantly larger than the planned 70 % and subsequently corresponds to the residue concentration of less than 30 mg/m3 . This is explained by the greater degree of capture and deposition of the sorbent on the chain curtain (not more than 20 mg/m3 . The proposed device for treating gases enables: improvement in the efficiency of gas treatment; increased reliability; increase in the degree of treatment of the gas flow without the use of additional equipment; reduction in metal and design complexity; reduction on the cost of the treatment process and simplification in the device design.

  8. Magnetism reflectometer study shows LiF layers improve efficiency in spin valve devices

    Energy Technology Data Exchange (ETDEWEB)

    Bardoel, Agatha A [ORNL; Lauter, Valeria [ORNL; Szulczewski, Greg J [ORNL

    2012-01-01

    New, more efficient materials for spin valves - a device used in magnetic sensors, random access memories, and hard disk drives - may be on the way based on research using the magnetism reflectometer at Oak Ridge National Laboratory (ORNL). Spin valve devices work by means of two or more conducting magnetic material layers that alternate their electrical resistance depending on the layers alignment. Giant magnetoresistance is a quantum mechanical effect first observed in thin film structures about 20 years ago. The effect is observed as a significant change in electrical resistance, depending on whether the magnetization of adjacent ferromagnetic layers is in a parallel or an antiparallel magnetic alignment. 'What we are doing here is developing new materials. The search for new materials suitable for injecting and transferring carriers with a preferential spin orientation is most important for the development of spintronics,' said Valeria Lauter, lead instrument scientist on the magnetism reflectometer at the Spallation Neutron Source (SNS), who collaborated on the experiment. The researchers discovered that the conductivity of such materials is improved when an organic polymer semiconductor layer is placed between the magnetic materials. Organic semiconductors are now the material of choice for future spin valve devices because they preserve spin coherence over longer times and distances than conventional semiconductors. While research into spin valves has been ongoing, research into organic semiconductors is recent. Previous research has shown that a 'conductivity mismatch' exists in spin valve systems in which ferromagnetic metal electrodes interface with such organic semiconductors as Alq3 ({pi}-conjugated molecule tris(8-hydroxy-quinoline) aluminium). This mismatch limits the efficient injection of the electrons from the electrodes at the interface with the semiconductor material. However, lithium fluoride (LiF), commonly used in light

  9. Device Strategies Directed to Improving the Efficiency of Solution-Processed Organic Solar Cells

    KAUST Repository

    Liang, Ru-Ze

    2018-04-18

    In the last decade, organic photovoltaics (OPVs) have been attracting much attention for their low cost, and feasibility of mass production in large-area modules. Reported power conversion efficiencies (PCE) of organic solar cells have reached more than 10%. These promising PCEs can be realized by uncovering important principles: (1) rational molecular design, (2) matching of the material energy level, (3) favorable morphology of donor-acceptor (D/A) network, (4) higher carrier mobilities, and (5) suppression of charge recombination within the bulk heterojunction (BHJ). Though these key properties are frequently stated, the relationships between these principles remain unclear, which motivates us to fill these gaps. In the beginning, we show that changing the sequence of donor and acceptor units of the benzodithiophene-core (BDT) SM donors critically impacts molecular packing and charge transport in BHJ solar cells. Moreover, we find out that by adding small amount of the external solvent additive, the domain size of the SMFQ1 become relatively smaller, resulting in the FF enhancement of ~70% and thus pushing PCE to >6.5%. To further improve the device performance, we utilize another technique of device optimization: Solvent Vapor Annealing (SVA). Compared with solvent additive, the SVA creates a solvent-saturated environment for SMs to re-arrange and crystalize, leading to PCE of >8%, with nearly-free bimolecular recombination. When the systems are shifted from fullerene acceptors to nonfullerene acceptors, using solvent additives in indacenodithiophene-core (IDT) systems significantly reduces the domain size from >500nm to <50nm and also allows the SM donors to orderly packed, rising the PCE from <1% to 4.5%. Furthermore in a similar IDT-based system, it shows unexpectedly high VOC and low energy loss, and high PCE > 6% can be reached by employing the dimethyl disulfide (DMDS) as the SVA solvent to re-organize the morphology from excessive mixing to ordered phase

  10. Computer model of copper resistivity will improve the efficiency of field-compression devices

    International Nuclear Information System (INIS)

    Burgess, T.J.

    1977-01-01

    By detonating a ring of high explosive around an existing magnetic field, we can, under certain conditions, compress the field and multiply its strength tremendously. In this way, we can duplicate for a fraction of a second the extreme pressures that normally exist only in the interior of stars and planets. Under such pressures, materials may exhibit behavior that will confirm or alter current notions about the fundamental structure of matter and the ongoing processes in planetary interiors. However, we cannot design an efficient field-compression device unless we can calculate the electrical resistivity of certain basic metal components, which interact with the field. To aid in the design effort, we have developed a computer code that calculates the resistivity of copper and other metals over the wide range of temperatures and pressures found in a field-compression device

  11. Joint Optimized CPU and Networking Control Scheme for Improved Energy Efficiency in Video Streaming on Mobile Devices

    Directory of Open Access Journals (Sweden)

    Sung-Woong Jo

    2017-01-01

    Full Text Available Video streaming service is one of the most popular applications for mobile users. However, mobile video streaming services consume a lot of energy, resulting in a reduced battery life. This is a critical problem that results in a degraded user’s quality of experience (QoE. Therefore, in this paper, a joint optimization scheme that controls both the central processing unit (CPU and wireless networking of the video streaming process for improved energy efficiency on mobile devices is proposed. For this purpose, the energy consumption of the network interface and CPU is analyzed, and based on the energy consumption profile a joint optimization problem is formulated to maximize the energy efficiency of the mobile device. The proposed algorithm adaptively adjusts the number of chunks to be downloaded and decoded in each packet. Simulation results show that the proposed algorithm can effectively improve the energy efficiency when compared with the existing algorithms.

  12. Improvement of wireless power transmission efficiency of implantable subcutaneous devices by closed magnetic circuit mechanism.

    Science.gov (United States)

    Jo, Sung-Eun; Joung, Sanghoon; Suh, Jun-Kyo Francis; Kim, Yong-Jun

    2012-09-01

    Induction coils were fabricated based on flexible printed circuit board for inductive transcutaneous power transmission. The coil had closed magnetic circuit (CMC) structure consisting of inner and outer magnetic core. The power transmission efficiency of the fabricated device was measured in the air and in vivo condition. It was confirmed that the CMC coil had higher transmission efficiency than typical air-core coil. The power transmission efficiency during a misalignment between primary coil and implanted secondary coil was also evaluated. The decrease of mutual inductance between the two coils caused by the misalignment led to a low efficiency of the inductive link. Therefore, it is important to properly align the primary coil and implanted secondary coil for effective power transmission. To align the coils, a feedback coil was proposed. This was integrated on the backside of the primary coil and enabled the detection of a misalignment of the primary and secondary coils. As a result of using the feedback coil, the primary and secondary coils could be aligned without knowledge of the position of the implanted secondary coil.

  13. Furnace devices aerodynamics optimization for fuel combustion efficiency improvement and nitrogen oxide emission reduction

    Science.gov (United States)

    Volkov, E. P.; Prokhorov, V. B.; Arkhipov, A. M.; Chernov, S. L.; Kirichkov, V. S.; Kaverin, A. A.

    2017-11-01

    MPEI conducts researches on physical and mathematical models of furnace chambers for improvement of power-generation equipment fuel combustion efficiency and ecological safety. Results of these researches are general principles of furnace aerodynamics arrangement for straight-flow burners and various fuels. It has been shown, that staged combustion arrangement with early heating and igniting with torch distribution in all furnace volume allows to obtain low carbon in fly ash and nitrogen oxide emission and also to improve boiler operation reliability with expand load adjustment range. For solid fuel combustion efficiency improvement it is practical to use high-placed and strongly down-tilted straight-flow burners, which increases high-temperature zone residence time for fuel particles. In some cases, for this combustion scheme it is possible to avoid slag-tap removal (STR) combustion and to use Dry-bottom ash removal (DBAR) combustion with tolerable carbon in fly ash level. It is worth noting that boilers with STR have very high nitrogen oxide emission levels (1200-1800 mg/m3) and narrow load adjustment range, which is determined by liquid slag output stability, so most industrially-developed countries don’t use this technology. Final decision about overhaul of boiler unit is made with regard to physical and mathematical modeling results for furnace and zonal thermal calculations for furnace and boiler as a whole. Overhaul of boilers to provide staged combustion and straight-flow burners and nozzles allows ensuring regulatory nitrogen oxide emission levels and corresponding best available technology criteria, which is especially relevant due to changes in Russian environmental regulation.

  14. An analysis of limits for part load efficiency improvement with VVA devices

    International Nuclear Information System (INIS)

    Knop, Vincent; Mattioli, Leonardo

    2015-01-01

    Highlights: • Variable valve actuation aims at reducing pumping losses for spark-ignition engines. • Fully unthrottled operation is never reached because of combustion degradation. • Present paper quantifies the combustion degradation origins for various strategies. • Fully unthrottled CAI combustion mode is a non-combustion-limited alternative. • Combustion limitation is, however, replaced by a heat loss limitation. - Abstract: The implementation of Variable Valve Actuation (VVA) in Spark-Ignition (SI) engines generally aims at increasing part-load efficiency by reducing pumping losses. However, any innovative valve strategy has effects on the combustion process itself, introducing new limitations and mitigating the fuel consumption benefits. The experimental analysis of such valve strategies identifies the optimum settings but does not explain the origin of benefits and the sources of unexpected drawbacks. In the present study, the experimentally-optimised operating conditions for different valve strategies were numerically compared with 3D CFD to gain knowledge about causes for efficiency benefits and consequences of valve strategy on combustion progress. We compared standard SI operation in a single-cylinder port-fuel injection gasoline engine to mixture leaning, early intake valve closure (Miller cycle), late intake valve closure (Atkinson cycle), as well as Controlled Auto-Ignition (CAI). All alternative methods reduced pumping work and improved fuel consumption. However, all alternative methods also altered combustion progress and thermodynamic state within the combustion chamber, so that the observed fuel consumption benefits never reached the expected values. An energy balance provided the additional losses induced by each strategy while in-cylinder turbulence and temperature quantification helped explain the trends in combustion speed.

  15. Algorithm of Energy Efficiency Improvement for Intelligent Devices in Railway Transport

    Directory of Open Access Journals (Sweden)

    Beinaroviča Anna

    2016-07-01

    Full Text Available The present paper deals with the use of systems and devices with artificial intelligence in the motor vehicle driving. The main objective of transport operations is a transportation planning with minimum energy consumption. There are various methods for energy saving, and the paper discusses one of them – proper planning of transport operations. To gain proper planning it is necessary to involve the system and devices with artificial intelligence. They will display possible developments in the choice of one or another transport plan. Consequently, it can be supposed how much the plan is effective against the spent energy. The intelligent device considered in this paper consists of an algorithm, a database, and the internet for the connection to other intelligent devices. The main task of the target function is to minimize the total downtime at intermediate stations. A specific unique PHP-based computer model was created. It uses the MySQL database for simulation data storage and processing. Conclusions based on the experiments were made. The experiments showed that after optimization, a train can pass intermediate stations without making multiple stops breaking and accelerating, which leads to decreased energy consumption.

  16. Improving the efficiency of microwave devices with a double output cavity

    International Nuclear Information System (INIS)

    Eppley, K.R.; Herrmannsfeldt, W.B.; Lee, T.G.

    1986-05-01

    Double output cavities have been used experimentally to increase the efficiency of high-power klystrons. We have used particle-in-cell simulations with the 2 + 1/2 dimensional code MASK to optimize the design of double output cavities for the lasertron and the 50 MW klystron under development at SLAC. We discuss design considerations for double output cavities (e.g., optimum choice of voltages and phases, efficiency, wall interception, breakdown). We describe how one calculates the cavity impedance matrix from the gap voltages and phases. Simulation results are compared to experience with the 150 MW klystron

  17. Efficient adders for assistive devices

    Directory of Open Access Journals (Sweden)

    Mansi Jhamb

    2017-02-01

    Full Text Available The Body sensor network [IEEE 802.15] is a wireless communication network consisting of assistive devices which are of prime importance in medical applications. The delay critical and power hungry blocks in these assistive devices are designed so that they consume less power, have low latency and require a lesser area on chip. In this paper, we present a qualitative as well as a quantitative analysis of an asynchronous pipelined adder design with two latest computation completion sensing approaches based on Pseudo NMOS logic and other based on C-element. The Pseudo NMOS based completion sensing approach provides a maximum improvement of 76.92% in critical path delay at supply voltage of 1.2 V and the maximum drop in power dissipation has been observed at a supply voltage of 1.1 V which is 85.60% as compared to C-element based completion sensing approach. Even at low voltages such as 0.8 V, there is a significant improvement in speed and power which is 75.64% and 74.79% respectively. Since the adder is the most widely used component in all present day assistive devices, this analysis acts as a pointer for the application of asynchronous pipelined circuits with efficient Pseudo NMOS based completion sensing approach in low voltage/low power rehabilitative devices.

  18. Improved color purity and efficiency by a coguest emitter system in doped red light-emitting devices

    Energy Technology Data Exchange (ETDEWEB)

    Chen Jiangshan [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of Chinese Academy of Sciences, Changchun 130022 (China); Ma Dongge [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of Chinese Academy of Sciences, Changchun 130022 (China)]. E-mail: mdg1014@ciac.jl.cn

    2007-01-15

    We demonstrate red organic light-emitting diodes (OLEDs) with improved color purity and electroluminescence (EL) efficiency by codoping a green fluorescent sensitizer 10-(2-benzothiazolyl)-2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H,5H,11H -(1)-benzopyropyrano(6,7-8-i,j)quinolizin-11-one (C545T) as the second dopant and a red fluorescent dye 4-(dicyanomethylene)-2-t-butyl-6(1,1,7,7-tetramethyljulolidyl-9-enyl) -4H-pyran (DCJTB) as the lumophore into tris(8-hydroquinoline) aluminum (Alq{sub 3}) host. It was found that the C545T dopant did not by itself emit but assisted the carrier trapping from the host Alq{sub 3} to the red emitting dopant. The red OLEDs realized by this approach not only kept the purity of the emission color, but also significantly improved the EL efficiency. The current efficiency and power efficiency, respectively, reached 12cd/A at a current density of 0.3mA/cm{sup 2} and 10lm/W at a current density of 0.02mA/cm{sup 2}, which are enhanced by 1.4 and 2.6 times compared with devices where the emissive layer is composed of the DCJTB doped Alq{sub 3}, and a stable red emission (chromaticity coordinates: x=0.64, y=0.36) was obtained in a wide range of voltage. Our results indicate that the coguest system is a promising method for obtaining high-efficiency red OLEDs.

  19. On Improving the Energy Efficiency and Robustness of Position Tracking for Mobile Devices

    DEFF Research Database (Denmark)

    Kjærgaard, Mikkel Baun

    2010-01-01

    position updates when faced with changing conditions such as delays and changing positioning conditions. Previous work has established dynamic tracking systems, such as our EnTracked system, as a solution to address these issues. In this paper we propose a responsibility division for position tracking...... into sensor management strategies and position update protocols and combine the sensor management strategy of EnTracked with position update protocols, which enables the system to further reduce the power consumption with up to 268 mW extending the battery life with up to 36\\%. As our evaluation identify...... that classical position update protocols have robustness weaknesses we propose a method to improve their robustness. Furthermore, we analyze the dependency of tracking systems on the pedestrian movement patterns and positioning environment, and how the power savings depend on the power characteristics...

  20. Improved efficiency in organic light-emitting devices with tris-(8-hydroxyquinoline) aluminium doped 9,10-di(2-naphthyl) anthracene emission layer

    Energy Technology Data Exchange (ETDEWEB)

    Yuan Yongbo; Lian Jiarong; Li Shuang; Zhou Xiang [State Key Lab of Optoelectronic Materials and Technologies, Sun Yat-Sen University, Guangzhou, 510275 (China)], E-mail: stszx@mail.sysu.edu.cn

    2008-11-21

    Organic light-emitting devices with tris-(8-hydroxyquinoline) aluminium (Alq{sub 3}) doped 9,10-di(2-naphthyl) anthracene (ADN) as the emission layer (EML) have been fabricated. These devices exhibit efficient electroluminescence (EL) originated from the Alq{sub 3} as the mass ratio of Alq{sub 3} to ADN was varied from 1 to 50%. The devices with an optimal Alq{sub 3} mass ratio of 10 wt% showed a peak EL efficiency and an external quantum efficiency of 9.1 cd A{sup -1} and 2.7% at a luminance of 1371 cd m{sup -2}, which is improved by a factor of 2.2 compared with 4.1 cd A{sup -1} and 1.2% at a luminance of 3267 cd m{sup -2} for conventional devices with the neat Alq{sub 3} as the EML.

  1. The dynamic modeling and design improvement of a piezoelectric exciter of a touch screen device for efficient tactile feedback

    International Nuclear Information System (INIS)

    Park, Young-Min; Kim, Kwang-Joon

    2011-01-01

    Piezoelectric exciters have been receiving greater attention recently as a vibration source for tactile feedback in devices with touch screens, such as a mobile phones, in place of DC motors due to lower energy consumption and smaller volume. Their insufficient excitation level, however, still remains a problem. In this paper, dynamic modeling and design improvement of a piezoelectric exciter are presented. The excitation performance is defined as the acceleration response at the center of a touch screen per electric power and to be maximized around 250 Hz where the index finger is most sensitive. The piezoelectric exciter consists of a z-shaped metal beam, a piezoelectric layer on the long horizontal segment and an adhesive layer between the short horizontal segment and the touch screen. Assuming that the piezoelectric exciter is attached onto a rigid ground due to its low mechanical impedance compared with that of the touch screen, the piezoelectric exciter is dynamically modeled by applying Hamilton's principle, where the adhesive layer is treated as a distributed stiffness. The touch screen is modeled approximately as a simply supported beam such that it may have the same fundamental natural frequency and bending stiffness as the screen based on measurements. The performance improvement is focused on the change of five geometric parameters of the piezoelectric exciter: length of the long horizontal segment, thickness of the piezoelectric layer, thickness of the elastic metal layer, width of the beams and tip mass. The procedure to improve the performance of the piezoelectric exciter via dynamic modeling is presented together with experimental results on a prototype. Effectiveness of the design modification and limitations in practice are further discussed as well

  2. Improving efficiency in stereology

    DEFF Research Database (Denmark)

    Keller, Kresten Krarup; Andersen, Ina Trolle; Andersen, Johnnie Bremholm

    2013-01-01

    of the study was to investigate the time efficiency of the proportionator and the autodisector on virtual slides compared with traditional methods in a practical application, namely the estimation of osteoclast numbers in paws from mice with experimental arthritis and control mice. Tissue slides were scanned......, a proportionator sampling and a systematic, uniform random sampling were simulated. We found that the proportionator was 50% to 90% more time efficient than systematic, uniform random sampling. The time efficiency of the autodisector on virtual slides was 60% to 100% better than the disector on tissue slides. We...... conclude that both the proportionator and the autodisector on virtual slides may improve efficiency of cell counting in stereology....

  3. Efficient micromagnetics for magnetic storage devices

    Science.gov (United States)

    Escobar Acevedo, Marco Antonio

    Micromagnetics is an important component for advancing the magnetic nanostructures understanding and design. Numerous existing and prospective magnetic devices rely on micromagnetic analysis, these include hard disk drives, magnetic sensors, memories, microwave generators, and magnetic logic. The ability to examine, describe, and predict the magnetic behavior, and macroscopic properties of nanoscale magnetic systems is essential for improving the existing devices, for progressing in their understanding, and for enabling new technologies. This dissertation describes efficient micromagnetic methods as required for magnetic storage analysis. Their performance and accuracy is demonstrated by studying realistic, complex, and relevant micromagnetic system case studies. An efficient methodology for dynamic micromagnetics in large scale simulations is used to study the writing process in a full scale model of a magnetic write head. An efficient scheme, tailored for micromagnetics, to find the minimum energy state on a magnetic system is presented. This scheme can be used to calculate hysteresis loops. An efficient scheme, tailored for micromagnetics, to find the minimum energy path between two stable states on a magnetic system is presented. This minimum energy path is intimately related to the thermal stability.

  4. Factors limiting device efficiency in organic photovoltaics

    NARCIS (Netherlands)

    Janssen, R.A.J.; Nelson, J.

    2013-01-01

    The power conversion efficiency of the most efficient organic photovoltaic (OPV) cells has recently increased to over 10%. To enable further increases, the factors limiting the device efficiency in OPV must be identified. In this review, the operational mechanism of OPV cells is explained and the

  5. Multi variable control of a switched ignition device: efficiency improvement under various constraints; Commande multivariable d`un moteur a allumage commande: Amelioration du rendement sous differentes contraintes

    Energy Technology Data Exchange (ETDEWEB)

    Chaumerliac, V

    1995-03-09

    Spark-ignition engine control needs substantial improvement for various reasons: a non-linear and multivariable process, the strictness of anti-pollution constraints, the necessity of fuel economy, the variable running conditions, the aging, the reliability and the cost. The improvement of engine efficiency will be involved in this context and with the pollution constraints. This work develops a system approach and its philosophy is based on a suitable description of the main dynamics. A compartmentalized model of a spark-ignition engine and the dynamic of the vehicle is presented. The aim of this modeling is to have a good representativeness in transients and to describe the behavior of the outputs useful for control. The multivariable control is split in two independent systems. The first one controls the spark advance control to obtain the maximum torque. The second one controls the throttle and the electronic fuel injection device to have lower pollutant emissions. The spark advance closed loop control uses information measured with either a cylinder pressure sensor or a torque sensor. These studies have achieved to an adaptive tuning on engine bench. A new actuator, the electronic throttle control, can provide a higher degree of precision for the fuel/air ratio regulation system, particularly during fast accelerations and decelerations. An intake manifold pressure control is developed to coordinate the air and fuel flows. A delay strategy and a simple compensation of fuel supply dynamics allow to obtain good results on engine bench. Uncoupling the acceleration pedal and the throttle command is a promising way to improve engine efficiency and reduce exhaust emission during transient phases. (author) 59 refs.

  6. Efficiency improvements in transport

    Energy Technology Data Exchange (ETDEWEB)

    Schramm, J. [Technical Univ. of Denmark. DTU Mechanical Engineering, Kgs. Lyngby (Denmark); Christensen, Linda; Jensen, Thomas C. [Technical Univ. of Denmark. DTU Transport, Kgs. Lyngby (Denmark)

    2012-11-15

    Transport of people, personal belongings and goods in private cars is fundamental to our modern welfare society and economic growth, and has grown steadily over many decades. Motor fuels have been based almost entirely on crude oil for the last century. During the last couple of decades engines built for traditional fuels have become more advanced and efficient; this has reduced fuel consumption by around 40% and emissions by more than 90%. Only in the same time span have we begun to look at alternatives to fossil fuels. Biofuels such as biodiesel, bioethanol, biomethanol and biogas can replace petrol and diesel, and in recent years algae have shown a new potential for diesel fuel. Natural gas is also becoming an interesting fuel due to its large resources worldwide. GTL, CTL and BTL are liquid fuels produced from solid or gaseous sources. GTL and CTL are expensive to produce and not very CO{sub 2}-friendly, but they are easily introduced and need little investment in infrastructure and vehicles. DME is an excellent fuel for diesel engines. Methanol and DME produced from biomass are among the most CO{sub 2}-reducing fuels and at the same time the most energy-efficient renewable fuels. Fuel cell vehicles (FCVs) are currently fuelled by hydrogen, but other fuels are also possible. There are, however, several barriers to the implementation of fuel cell vehicles. In particular, a hydrogen infrastructure needs to be developed. Electric vehicles (EVs) have the advantage that energy conversion is centralised at the power plant where it can be done at optimum efficiency and emissions. EVs have to be charged at home, and also away from home when travelling longer distances. With an acceptable fast charging infrastructure at least 85% of the one-car families in Denmark could be potential EV customers. Range improvements resulting from better batteries are expected to create a large increase in the number of EVs in Denmark between 2020 and 2030. The hybrid electric vehicle

  7. External shading devices for energy efficient building

    Science.gov (United States)

    Shahdan, M. S.; Ahmad, S. S.; Hussin, M. A.

    2018-02-01

    External shading devices on a building façade is an important passive design strategy as they reduce solar radiation. Although studies have proven the benefits of external shading devices, many are designed solely for aesthetic purposes without fully considering its high potential to reduce solar radiation and glare. Furthermore, explorations into shading devices by the design team are mostly left too late in the design development phases. Hence, the paper looks into the effectiveness of external shading devices on a building towards more energy efficient building. The study aims to analyse the effects of various configurations of external shading devices towards the energy consumption of a case study building based on computer simulations. This study uses Building Information Modelling (BIM) through Autodesk Revit software as simulation tool. The constant variables for the simulation are the orientation of the building, types of glazing used by the building and the internal loads of the building. Whereas, the manipulated variable is the types of shading device used. The data were sorted according to the categories and translated into a chart. Analysis of the findings indicate that shading devices with different configurations show significant results in the energy consumption and the best configuration is the egg-crate shading devices. The study recommends that the consideration for shading device as a passive design strategy needs to be developed at the early stage of the building design.

  8. Architectures for Improved Organic Semiconductor Devices

    Science.gov (United States)

    Beck, Jonathan H.

    , semiconductors and substrates compatible with low-temperature, flexible, and oxygenated and aromatic solvent-free fabrication. Materials and processes must be capable of future high volume production in order to enable low costs. In this thesis we explore several techniques to improve organic semiconductor device performance and enable new fabrication processes. In Chapter 2, I describe the integration of sub-optical-wavelength nanostructured electrodes that improve fill factor and power conversion efficiency in organic photovoltaic devices. Photovoltaic fill factor performance is one of the primary challenges facing organic photovoltaics because most organic semiconductors have poor charge mobility. Our electrical and optical measurements and simulations indicate that nanostructured electrodes improve charge extraction in organic photovoltaics. In Chapter 3, I describe a general method for maximizing the efficiency of organic photovoltaic devices by simultaneously optimizing light absorption and charge carrier collection. We analyze the potential benefits of light trapping strategies for maximizing the overall power conversion efficiency of organic photovoltaic devices. This technique may be used to improve organic photovoltaic materials with low absorption, or short exciton diffusion and carrier-recombination lengths, opening up the device design space. In Chapter 4, I describe a process for high-quality graphene transfer onto chemically sensitive, weakly interacting organic semiconductor thin-films. Graphene is a promising flexible and highly transparent electrode for organic electronics; however, transferring graphene films onto organic semiconductor devices was previously impossible. We demonstrate a new transfer technique based on an elastomeric stamp coated with an fluorinated polymer release layer. We fabricate three classes of organic semiconductor devices: field effect transistors without high temperature annealing, transparent organic light-emitting diodes, and

  9. Improving Gas Flooding Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Reid Grigg; Robert Svec; Zheng Zeng; Alexander Mikhalin; Yi Lin; Guoqiang Yin; Solomon Ampir; Rashid Kassim

    2008-03-31

    This study focuses on laboratory studies with related analytical and numerical models, as well as work with operators for field tests to enhance our understanding of and capabilities for more efficient enhanced oil recovery (EOR). Much of the work has been performed at reservoir conditions. This includes a bubble chamber and several core flood apparatus developed or modified to measure interfacial tension (IFT), critical micelle concentration (CMC), foam durability, surfactant sorption at reservoir conditions, and pressure and temperature effects on foam systems.Carbon dioxide and N{sub 2} systems have been considered, under both miscible and immiscible conditions. The injection of CO2 into brine-saturated sandstone and carbonate core results in brine saturation reduction in the range of 62 to 82% brine in the tests presented in this paper. In each test, over 90% of the reduction occurred with less than 0.5 PV of CO{sub 2} injected, with very little additional brine production after 0.5 PV of CO{sub 2} injected. Adsorption of all considered surfactant is a significant problem. Most of the effect is reversible, but the amount required for foaming is large in terms of volume and cost for all considered surfactants. Some foams increase resistance to the value beyond what is practical in the reservoir. Sandstone, limestone, and dolomite core samples were tested. Dissolution of reservoir rock and/or cement, especially carbonates, under acid conditions of CO2 injection is a potential problem in CO2 injection into geological formations. Another potential change in reservoir injectivity and productivity will be the precipitation of dissolved carbonates as the brine flows and pressure decreases. The results of this report provide methods for determining surfactant sorption and can be used to aid in the determination of surfactant requirements for reservoir use in a CO{sub 2}-foam flood for mobility control. It also provides data to be used to determine rock permeability

  10. Informatics in radiology: Efficiency metrics for imaging device productivity.

    Science.gov (United States)

    Hu, Mengqi; Pavlicek, William; Liu, Patrick T; Zhang, Muhong; Langer, Steve G; Wang, Shanshan; Place, Vicki; Miranda, Rafael; Wu, Teresa Tong

    2011-01-01

    Acute awareness of the costs associated with medical imaging equipment is an ever-present aspect of the current healthcare debate. However, the monitoring of productivity associated with expensive imaging devices is likely to be labor intensive, relies on summary statistics, and lacks accepted and standardized benchmarks of efficiency. In the context of the general Six Sigma DMAIC (design, measure, analyze, improve, and control) process, a World Wide Web-based productivity tool called the Imaging Exam Time Monitor was developed to accurately and remotely monitor imaging efficiency with use of Digital Imaging and Communications in Medicine (DICOM) combined with a picture archiving and communication system. Five device efficiency metrics-examination duration, table utilization, interpatient time, appointment interval time, and interseries time-were derived from DICOM values. These metrics allow the standardized measurement of productivity, to facilitate the comparative evaluation of imaging equipment use and ongoing efforts to improve efficiency. A relational database was constructed to store patient imaging data, along with device- and examination-related data. The database provides full access to ad hoc queries and can automatically generate detailed reports for administrative and business use, thereby allowing staff to monitor data for trends and to better identify possible changes that could lead to improved productivity and reduced costs in association with imaging services. © RSNA, 2011.

  11. Improving Perovskite Solar Cells: Insights From a Validated Device Model

    NARCIS (Netherlands)

    Sherkar, Tejas S.; Momblona, Cristina; Gil-Escrig, Lidon; Bolink, Henk J.; Koster, L. Jan Anton

    2017-01-01

    To improve the efficiency of existing perovskite solar cells (PSCs), a detailed understanding of the underlying device physics during their operation is essential. Here, a device model has been developed and validated that describes the operation of PSCs and quantitatively explains the role of

  12. Frontier technologies to improve efficiency

    International Nuclear Information System (INIS)

    Kalhammer, F.R.

    1992-01-01

    The author discusses conservation technology to improve the efficiency of energy production. Although coal is seen as the largest source of fuel for producing electricity until the year 2040, the heating value of coal is expected to be increased by using Integrated Gasification Combined Cycle (IGCC) technology. Use of fuel cells to produce electricity will be a viable option only if costs can be reduced to make the technology competitive. By coupling IGCC with fuel cells it may be possible to increase total conversion efficiency of coal to electricity at 50%. Photovoltaics technology is more likely to be used in developing countries. Electric utilities target power electronics, lighting fixtures, heat pumps, plasma processing, freeze concentration and application of superconductivity as electricity end use technologies that have the most potential for efficiency improvement. The impact of these technologies in coping with the greenhouse effect was not addressed

  13. GATE: Improving the computational efficiency

    International Nuclear Information System (INIS)

    Staelens, S.; De Beenhouwer, J.; Kruecker, D.; Maigne, L.; Rannou, F.; Ferrer, L.; D'Asseler, Y.; Buvat, I.; Lemahieu, I.

    2006-01-01

    GATE is a software dedicated to Monte Carlo simulations in Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET). An important disadvantage of those simulations is the fundamental burden of computation time. This manuscript describes three different techniques in order to improve the efficiency of those simulations. Firstly, the implementation of variance reduction techniques (VRTs), more specifically the incorporation of geometrical importance sampling, is discussed. After this, the newly designed cluster version of the GATE software is described. The experiments have shown that GATE simulations scale very well on a cluster of homogeneous computers. Finally, an elaboration on the deployment of GATE on the Enabling Grids for E-Science in Europe (EGEE) grid will conclude the description of efficiency enhancement efforts. The three aforementioned methods improve the efficiency of GATE to a large extent and make realistic patient-specific overnight Monte Carlo simulations achievable

  14. Improving plasmonic waveguides coupling efficiency using nanoantennas

    DEFF Research Database (Denmark)

    Andryieuski, Andrei; Malureanu, Radu; Bouillard, Jean-Sebastien

    2012-01-01

    . The classical dipole antenna scheme can be improved by changing the nanoantenna geometry, adding constructive elements such as reflecting bars and mirrors and using arrays of antennas. The modelling designates that the coupling efficiency from a vertical fiber to a plasmonic waveguide can be improved more than......Plasmonic waveguides bear a lot of potential for photonic applications. However, one of the challenges for implementing them in devices is the low coupling efficiency to and from optical fibers. We report on our approach to facilitate the coupling efficiency with the use of metallic nanoantennas...... in 180 times in comparison with a direct fiber-waveguide coupling. Pros and cons of each configuration are discussed. Fabrication and characterisation results are reported....

  15. Improved efficiency in OLEDs with a thin Alq3 interlayer

    International Nuclear Information System (INIS)

    Lian Jiarong; Yuan Yongbo; Cao Lingfang; Zhang Jie; Pang Hongqi; Zhou Yunfei; Zhou Xiang

    2007-01-01

    We demonstrate an improved efficiency in OLEDs with a thin Alq 3 interlayer, which is inserted into the hole-transport layer for adjusting the hole-injection and transport, and improving the hole-electron balance. The thin Alq 3 interlayer can effectively influence the electrical performance and electroluminescence (EL) efficiency of the devices. The devices with an optimum Alq 3 interlayer exhibit a maximum EL efficiency of around 3.3 cd/A, which is improved by a factor of two over the conventional devices (1.6 cd/A) without the interlayer

  16. Energy efficient hybrid computing systems using spin devices

    Science.gov (United States)

    Sharad, Mrigank

    Emerging spin-devices like magnetic tunnel junctions (MTJ's), spin-valves and domain wall magnets (DWM) have opened new avenues for spin-based logic design. This work explored potential computing applications which can exploit such devices for higher energy-efficiency and performance. The proposed applications involve hybrid design schemes, where charge-based devices supplement the spin-devices, to gain large benefits at the system level. As an example, lateral spin valves (LSV) involve switching of nanomagnets using spin-polarized current injection through a metallic channel such as Cu. Such spin-torque based devices possess several interesting properties that can be exploited for ultra-low power computation. Analog characteristic of spin current facilitate non-Boolean computation like majority evaluation that can be used to model a neuron. The magneto-metallic neurons can operate at ultra-low terminal voltage of ˜20mV, thereby resulting in small computation power. Moreover, since nano-magnets inherently act as memory elements, these devices can facilitate integration of logic and memory in interesting ways. The spin based neurons can be integrated with CMOS and other emerging devices leading to different classes of neuromorphic/non-Von-Neumann architectures. The spin-based designs involve `mixed-mode' processing and hence can provide very compact and ultra-low energy solutions for complex computation blocks, both digital as well as analog. Such low-power, hybrid designs can be suitable for various data processing applications like cognitive computing, associative memory, and currentmode on-chip global interconnects. Simulation results for these applications based on device-circuit co-simulation framework predict more than ˜100x improvement in computation energy as compared to state of the art CMOS design, for optimal spin-device parameters.

  17. Observations on Power-Efficiency Trends in Mobile Communication Devices

    Directory of Open Access Journals (Sweden)

    Jyrkkä Kari

    2007-01-01

    Full Text Available Computing solutions used in mobile communications equipment are similar to those in personal and mainframe computers. The key differences between the implementations at chip level are the low leakage silicon technology and lower clock frequency used in mobile devices. The hardware and software architectures, including the operating system principles, are strikingly similar, although the mobile computing systems tend to rely more on hardware accelerators. As the performance expectations of mobile devices are increasing towards the personal computer level and beyond, power efficiency is becoming a major bottleneck. So far, the improvements of the silicon processes in mobile phones have been exploited by software designers to increase functionality and to cut development time, while usage times, and energy efficiency, have been kept at levels that satisfy the customers. Here we explain some of the observed developments and consider means of improving energy efficiency. We show that both processor and software architectures have a big impact on power consumption. Properly targeted research is needed to find the means to explicitly optimize system designs for energy efficiency, rather than maximize the nominal throughputs of the processor cores used.

  18. Observations on Power-Efficiency Trends in Mobile Communication Devices

    Directory of Open Access Journals (Sweden)

    Kari Jyrkkä

    2007-03-01

    Full Text Available Computing solutions used in mobile communications equipment are similar to those in personal and mainframe computers. The key differences between the implementations at chip level are the low leakage silicon technology and lower clock frequency used in mobile devices. The hardware and software architectures, including the operating system principles, are strikingly similar, although the mobile computing systems tend to rely more on hardware accelerators. As the performance expectations of mobile devices are increasing towards the personal computer level and beyond, power efficiency is becoming a major bottleneck. So far, the improvements of the silicon processes in mobile phones have been exploited by software designers to increase functionality and to cut development time, while usage times, and energy efficiency, have been kept at levels that satisfy the customers. Here we explain some of the observed developments and consider means of improving energy efficiency. We show that both processor and software architectures have a big impact on power consumption. Properly targeted research is needed to find the means to explicitly optimize system designs for energy efficiency, rather than maximize the nominal throughputs of the processor cores used.

  19. Electromagnetic Radiation Efficiency of Body-Implanted Devices

    Science.gov (United States)

    Nikolayev, Denys; Zhadobov, Maxim; Karban, Pavel; Sauleau, Ronan

    2018-02-01

    Autonomous wireless body-implanted devices for biotelemetry, telemedicine, and neural interfacing constitute an emerging technology providing powerful capabilities for medicine and clinical research. We study the through-tissue electromagnetic propagation mechanisms, derive the optimal frequency range, and obtain the maximum achievable efficiency for radiative energy transfer from inside a body to free space. We analyze how polarization affects the efficiency by exciting TM and TE modes using a magnetic dipole and a magnetic current source, respectively. Four problem formulations are considered with increasing complexity and realism of anatomy. The results indicate that the optimal operating frequency f for deep implantation (with a depth d ≳3 cm ) lies in the (108- 109 )-Hz range and can be approximated as f =2.2 ×107/d . For a subcutaneous case (d ≲3 cm ), the surface-wave-induced interference is significant: within the range of peak radiation efficiency (about 2 ×108 to 3 ×109 Hz ), the max-to-min ratio can reach a value of 6.5. For the studied frequency range, 80%-99% of radiation efficiency is lost due to the tissue-air wave-impedance mismatch. Parallel polarization reduces the losses by a few percent; this effect is inversely proportional to the frequency and depth. Considering the implantation depth, the operating frequency, the polarization, and the directivity, we show that about an order-of-magnitude efficiency improvement is achievable compared to existing devices.

  20. Efficiency improvements of offline metrology job creation

    Science.gov (United States)

    Zuniga, Victor J.; Carlson, Alan; Podlesny, John C.; Knutrud, Paul C.

    1999-06-01

    Progress of the first lot of a new design through the production line is watched very closely. All performance metrics, cycle-time, in-line measurement results and final electrical performance are critical. Rapid movement of this lot through the line has serious time-to-market implications. Having this material waiting at a metrology operation for an engineer to create a measurement job plan wastes valuable turnaround time. Further, efficient use of a metrology system is compromised by the time required to create and maintain these measurement job plans. Thus, having a method to develop metrology job plans prior to the actual running of the material through the manufacture area can significantly improve both cycle time and overall equipment efficiency. Motorola and Schlumberger have worked together to develop and test such a system. The Remote Job Generator (RJG) created job plans for new device sin a manufacturing process from an NT host or workstation, offline. This increases available system tim effort making production measurements, decreases turnaround time on job plan creation and editing, and improves consistency across job plans. Most importantly this allows job plans for new devices to be available before the first wafers of the device arrive at the tool for measurement. The software also includes a database manager which allows updates of existing job plans to incorporate measurement changes required by process changes or measurement optimization. This paper will review the result of productivity enhancements through the increased metrology utilization and decreased cycle time associated with the use of RJG. Finally, improvements in process control through better control of Job Plans across different devices and layers will be discussed.

  1. Improvements in backscatter measurement devices

    International Nuclear Information System (INIS)

    Saunders, J.; Hay, W.D.

    1978-01-01

    Improvements in measuring the thickness of a coating on a substrate by the technique of backscattered particles are described. These improvements enable the measurements to be carried out continuously as an integral part of the coating production line and also permit measurements where the coated elements are separated from one another by a predetermined distance. The former is achieved by situating the backscatter probe and detector on the rim of the measurement wheel and rotating this wheel at a speed such that the coated element and probe are stationary relative to one another. The latter improvement is achieved by an indexing apparatus which automatically positions the probe beside a coated element. (U.K.)

  2. Progress in high-efficient solution process organic photovoltaic devices fundamentals, materials, devices and fabrication

    CERN Document Server

    Li, Gang

    2015-01-01

    This book presents an important technique to process organic photovoltaic devices. The basics, materials aspects and manufacturing of photovoltaic devices with solution processing are explained. Solution processable organic solar cells - polymer or solution processable small molecules - have the potential to significantly reduce the costs for solar electricity and energy payback time due to the low material costs for the cells, low cost and fast fabrication processes (ambient, roll-to-roll), high material utilization etc. In addition, organic photovoltaics (OPV) also provides attractive properties like flexibility, colorful displays and transparency which could open new market opportunities. The material and device innovations lead to improved efficiency by 8% for organic photovoltaic solar cells, compared to 4% in 2005. Both academic and industry research have significant interest in the development of this technology. This book gives an overview of the booming technology, focusing on the solution process fo...

  3. Mushrooms as Efficient Solar Steam-Generation Devices.

    Science.gov (United States)

    Xu, Ning; Hu, Xiaozhen; Xu, Weichao; Li, Xiuqiang; Zhou, Lin; Zhu, Shining; Zhu, Jia

    2017-07-01

    Solar steam generation is emerging as a promising technology, for its potential in harvesting solar energy for various applications such as desalination and sterilization. Recent studies have reported a variety of artificial structures that are designed and fabricated to improve energy conversion efficiencies by enhancing solar absorption, heat localization, water supply, and vapor transportation. Mushrooms, as a kind of living organism, are surprisingly found to be efficient solar steam-generation devices for the first time. Natural and carbonized mushrooms can achieve ≈62% and ≈78% conversion efficiencies under 1 sun illumination, respectively. It is found that this capability of high solar steam generation is attributed to the unique natural structure of mushroom, umbrella-shaped black pileus, porous context, and fibrous stipe with a small cross section. These features not only provide efficient light absorption, water supply, and vapor escape, but also suppress three components of heat losses at the same time. These findings not only reveal the hidden talent of mushrooms as low-cost materials for solar steam generation, but also provide inspiration for the future development of high-performance solar thermal conversion devices. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Theoretical study on device efficiency of pulsed liquid jet pump

    International Nuclear Information System (INIS)

    Gao Chuanchang; Lu Hongqi; Wang Shicheng; Cheng Mingchuan

    2001-01-01

    The influence of the main factors on device efficiency of pulsed liquid jet pump with gas-liquid piston is analysed, the theoretical equation and its time-averaged solution of pulsed liquid jet pump device efficiency are derived. The theoretical and experimental results show that the efficiency of transmission of energy and mass to use pulsed jet is greatly raised, compared with steady jet, in the same device of liquid jet pump. The calculating results of time-averaged efficiency of pulsed liquid jet pump are approximately in agreement with the experimental results in our and foreign countries

  5. A Improved Seabed Surface Sand Sampling Device

    Science.gov (United States)

    Luo, X.

    2017-12-01

    In marine geology research it is necessary to obtain a suf fcient quantity of seabed surface samples, while also en- suring that the samples are in their original state. Currently,there are a number of seabed surface sampling devices available, but we fnd it is very diffcult to obtain sand samples using these devices, particularly when dealing with fne sand. Machine-controlled seabed surface sampling devices are also available, but generally unable to dive into deeper regions of water. To obtain larger quantities of seabed surface sand samples in their original states, many researchers have tried to improve upon sampling devices,but these efforts have generally produced ambiguous results, in our opinion.To resolve this issue, we have designed an improved andhighly effective seabed surface sand sampling device that incorporates the strengths of a variety of sampling devices. It is capable of diving into deepwater to obtain fne sand samples and is also suited for use in streams, rivers, lakes and seas with varying levels of depth (up to 100 m). This device can be used for geological mapping, underwater prospecting, geological engineering and ecological, environmental studies in both marine and terrestrial waters.

  6. Improvements in or relating to semiconductor devices

    International Nuclear Information System (INIS)

    Cooper, K.; Groves, I.S.; Leigh, P.A.; McIntyre, N.; O'Hara, S.; Speight, J.D.

    1980-01-01

    A method of producing semiconductor devices is described consisting of a series of physical and chemical techniques which results in the production of semiconductor devices such as IMPATT diodes of DC-RF efficiency and high reliability (lifetime). The diodes can be mass produced without significant variation of the technology. One of the techniques used is the high energy proton bombardment of the semiconductor material in depth to passivate specific zones. The energy of the protons is increased in stages at intervals of less than 0.11 MeV up to a predetermined maximum energy. (UK)

  7. Efficient Cross-Device Query Processing

    NARCIS (Netherlands)

    H. Pirk (Holger)

    2012-01-01

    htmlabstractThe increasing diversity of hardware within a single system promises large performance gains but also poses a challenge for data management systems. Strategies for the efficient use of hardware with large performance differences are still lacking. For example, existing research on GPU

  8. Making Image More Energy Efficient for OLED Smart Devices

    Directory of Open Access Journals (Sweden)

    Deguang Li

    2016-01-01

    Full Text Available Now, more and more mobile smart devices are emerging massively; energy consumption of these devices has become an important consideration due to the limitation of battery capacity. Displays are the dominant energy consuming component of battery-operated devices, giving rise to organic light-emitting diode (OLED as a new promising display technology, which consumes different power when displaying different content due to their emissive nature. Based on this property, we propose an approach to improve image energy efficiency on OLED displays by perceiving image content. The key idea of our approach is to eliminate undesired details while preserving the region of interest of the image by leveraging the color and spatial information. First, we use edge detection algorithm to extract region of interest (ROI of an image. Next, we gradually change luminance and saturation of region of noninterest (NON-ROI of the image. Then we perform detailed experiment and case study to validate our approach; experiment results show that our approach can save 22.5% energy on average while preserving high quality of the image.

  9. Mechanistic evaluation of the pros and cons of digital RT-LAMP for HIV-1 viral load quantification on a microfluidic device and improved efficiency via a two-step digital protocol.

    Science.gov (United States)

    Sun, Bing; Shen, Feng; McCalla, Stephanie E; Kreutz, Jason E; Karymov, Mikhail A; Ismagilov, Rustem F

    2013-02-05

    validation is essential before a method is considered to provide absolute quantification; (ii) the sensitivity of dLAMP to the sequence of the target nucleic acid necessitates additional validation with patient samples carrying the full spectrum of mutations; (iii) for multistep digital amplification chemistries, such as a combination of reverse transcription with amplification, microfluidic devices may be used to decouple these steps from one another and to perform them under different, individually optimized conditions for improved efficiency.

  10. Design of sample analysis device for iodine adsorption efficiency test in NPPs

    International Nuclear Information System (INIS)

    Ji Jinnan

    2015-01-01

    In nuclear power plants, iodine adsorption efficiency test is used to check the iodine adsorption efficiency of the iodine adsorber. The iodine adsorption efficiency can be calculated through the analysis of the test sample, and thus to determine if the performance of the adsorber meets the requirement on the equipment operation and emission. Considering the process of test and actual demand, in this paper, a special device for the analysis of this kind of test sample is designed. The application shows that the device is with convenient operation and high reliability and accurate calculation, and improves the experiment efficiency and reduces the experiment risk. (author)

  11. Corporate Accounting Policy Efficiency Improvement

    Directory of Open Access Journals (Sweden)

    Elena K. Vorobei

    2013-01-01

    Full Text Available The article is focused on the issues of efficient use of different methods of tax accounting for the optimization of income tax expenses and their consolidation in corporate accounting policy. The article makes reasoned conclusions, concerning optimal selection of depreciation methods for tax and bookkeeping accounting and their consolidation in corporate accounting policy and consolidation of optimal methods of cost recovery in production, considering business environment. The impact of the selected methods on corporate income tax rates and corporate property tax rates was traced and tax recovery was estimated.

  12. Efficient light-emitting devices based on platinum-complexes-anchored polyhedral oligomeric silsesquioxane materials

    KAUST Repository

    Yang, Xiaohui

    2010-08-24

    The synthesis, photophysical, and electrochemical characterization of macromolecules, consisting of an emissive platinum complex and carbazole moieties covalently attached to a polyhedral oligomeric silsesquioxane (POSS) core, is reported. Organic light-emitting devices based on these POSS materials exhibit a peak external quantum efficiency of ca. 8%, which is significantly higher than that of the analogous devices with a physical blend of the platinum complexes and a polymer matrix, and they represent noticeable improvement in the device efficiency of solution-processable phosphorescent excimer devices. Furthermore, the ratio of monomer and excimer/aggregate electroluminescent emission intensity, as well as the device efficiency, increases as the platinum complex moiety presence on the POSS macromolecules decreases. © 2010 American Chemical Society.

  13. Thermoelectric efficiency of nanoscale devices in the linear regime

    Science.gov (United States)

    Bevilacqua, G.; Grosso, G.; Menichetti, G.; Pastori Parravicini, G.

    2016-12-01

    We study quantum transport through two-terminal nanoscale devices in contact with two particle reservoirs at different temperatures and chemical potentials. We discuss the general expressions controlling the electric charge current, heat currents, and the efficiency of energy transmutation in steady conditions in the linear regime. With focus in the parameter domain where the electron system acts as a power generator, we elaborate workable expressions for optimal efficiency and thermoelectric parameters of nanoscale devices. The general concepts are set at work in the paradigmatic cases of Lorentzian resonances and antiresonances, and the encompassing Fano transmission function: the treatments are fully analytic, in terms of the trigamma functions and Bernoulli numbers. From the general curves here reported describing transport through the above model transmission functions, useful guidelines for optimal efficiency and thermopower can be inferred for engineering nanoscale devices in energy regions where they show similar transmission functions.

  14. Improving Energy Efficiency of Auxiliaries

    International Nuclear Information System (INIS)

    Carl T. Vuk

    2001-01-01

    The summaries of this report are: Economics Ultimately Dictates Direction; Electric Auxiliaries Provide Solid Benefits. The Impact on Vehicle Architecture Will be Important; Integrated Generators With Combined With Turbo Generators Can Meet the Electrical Demands of Electric Auxiliaries; Implementation Will Follow Automotive 42V Transition; Availability of Low Cost Hardware Will Slow Implementation; Industry Leadership and Cooperation Needed; Standards and Safety Protocols Will be Important. Government Can Play an Important Role in Expediting: Funding Technical Development; Incentives for Improving Fuel Economy; Developing Standards, Allowing Economy of Scale; and Providing Safety Guidelines

  15. Efficient red organic electroluminescent devices based on trivalent europium complex obtained by designing the device structure with stepwise energy levels

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Liang; Jiang, Yunlong; Cui, Rongzhen; Li, Yanan; Zhao, Xuesen; Deng, Ruiping; Zhang, Hongjie, E-mail: hongjie@ciac.ac.cn

    2016-02-15

    In this study, we aim to further enhance the electroluminescence (EL) performances of trivalent europium complex Eu(TTA){sub 3}phen (TTA=thenoyltrifluoroacetone and phen=1,10-phenanthroline) by designing the device structure with stepwise energy levels. The widely used bipolar material 2,6-bis(3-(9H-carbazol-9-yl)phenyl)pyridine (26DCzPPy) was chosen as host material, while the doping concentration of Eu(TTA){sub 3}phen was optimized to be 4%. To facilitate the injection and transport of holes, MoO{sub 3} anode modification layer and 4,4′,4′′-Tris(carbazole-9-yl)triphenylamine (TcTa) hole transport layer were inserted in sequence. Efficient pure red emission with suppressed efficiency roll-off was obtained attributed to the reduction of accumulation holes, the broadening of recombination zone, and the improved balance of holes and electrons on Eu(TTA){sub 3}phen molecules. Finally, the device with 3 nm MoO{sub 3} and 5 nm TcTa obtained the highest brightness of 3278 cd/m{sup 2}, current efficiency of 12.45 cd/A, power efficiency of 11.50 lm/W, and external quantum efficiency of 6.60%. Such a device design strategy helps to improve the EL performances of emitters with low-lying energy levels and provides a chance to simplify device fabrication processes. - Highlights: • Electroluminescent performances of europium complex were further improved. • Device structure with stepwise energy levels was designed. • Better carriers' balance was realized by improving the injection and transport of holes. • The selection of bipolar host caused the broadening of recombination zone.

  16. Energy-efficient Trajectory Tracking for Mobile Devices

    DEFF Research Database (Denmark)

    Kjærgaard, Mikkel Baun; Bhattacharya, Sourav; Blunck, Henrik

    2011-01-01

    Emergent location-aware applications often require tracking trajectories of mobile devices over a long period of time. To be useful, the tracking has to be energy-efficient to avoid having a major impact on the battery life of the mobile de vice. Furthermore, when trajectory information needs to ...

  17. EFFICIENT POLYMER PHOTOVOLTAIC DEVICES BASED ON POLYMER D-A BLENDS

    Institute of Scientific and Technical Information of China (English)

    Xian-yu Deng; Li-ping Zheng; Yue-qi Mo; Gang Yu; Wei Yang; Wen-hua Weng; Yong Cao

    2001-01-01

    Recent work demonstrated that efficient solar-energy conversion could be achieved in polymer photovoltaic cells (PVCs) based on interpenetrating bi-continuous networks[1,2]. In this paper we present a comprehensive study on improving energy conversion efficiencies of PVCs based on composite films of MEHPPV and fullerene derivatives. Carrier collection efficiency of ca. 30% el/ph and energy conversion efficiency of 3.9% were achieved at 500 nm. At reverse bias of 15 V, the photosensitivity reached 0.8 A/W, corresponding to a quantum efficiency over 100% el/ph. These results suggest that high efficiency photoelectric conversion can be achieved in polymer devices with M-P-M structure. These devices are promising for practical applications such as plastic solar cells and plastic photodetectors.

  18. Highly Flexible and Efficient Solar Steam Generation Device.

    Science.gov (United States)

    Chen, Chaoji; Li, Yiju; Song, Jianwei; Yang, Zhi; Kuang, Yudi; Hitz, Emily; Jia, Chao; Gong, Amy; Jiang, Feng; Zhu, J Y; Yang, Bao; Xie, Jia; Hu, Liangbing

    2017-08-01

    Solar steam generation with subsequent steam recondensation has been regarded as one of the most promising techniques to utilize the abundant solar energy and sea water or other unpurified water through water purification, desalination, and distillation. Although tremendous efforts have been dedicated to developing high-efficiency solar steam generation devices, challenges remain in terms of the relatively low efficiency, complicated fabrications, high cost, and inability to scale up. Here, inspired by the water transpiration behavior of trees, the use of carbon nanotube (CNT)-modified flexible wood membrane (F-Wood/CNTs) is demonstrated as a flexible, portable, recyclable, and efficient solar steam generation device for low-cost and scalable solar steam generation applications. Benefitting from the unique structural merits of the F-Wood/CNTs membrane-a black CNT-coated hair-like surface with excellent light absorbability, wood matrix with low thermal conductivity, hierarchical micro- and nanochannels for water pumping and escaping, solar steam generation device based on the F-Wood/CNTs membrane demonstrates a high efficiency of 81% at 10 kW cm -2 , representing one of the highest values ever-reported. The nature-inspired design concept in this study is straightforward and easily scalable, representing one of the most promising solutions for renewable and portable solar energy generation and other related phase-change applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. The Gains from Improved Market Efficiency

    DEFF Research Database (Denmark)

    Persson, Karl Gunnar; Ejrnæs, Mette

    faster, violations of the law of one price become smaller and hence less persistent. There were also significant gains from improved market efficiency but that improvement took place after the information ‘regime’ shifted from pre-telegraphic communication to a regime with swift transmission...... of information in an era which developed a sophisticated commercial press and telegraphic communication. Improved market efficiency probably stimulated trade more than falling transport costs......This paper looks at the gains from improved market efficiency in long-distance grain trade in the second half of the 19th century when violations of the law of one price were reduced due to improved information transmission. Two markets, a major export centre, Chicago, and a major importer...

  20. Common challenge in resource efficiency improvement

    International Nuclear Information System (INIS)

    La Motta, Sergio; Peronaci, Marcello

    2015-01-01

    Energy efficiency and technology improvements on their own will not achieve the Low Carbon Societies (LCS) goals. Thus, resource efficiency and a circular economy are keys to a low carbon society. Resource efficiency improvement potential has been analysed from the industrial and territorial management perspectives. Exploring synergies between LCS and the larger area of sustainable development and green economy, highlighting co-benefits and trade-offs, is of utmost importance to pave the way to a more equitable and largely participated low carbon transition.

  1. Progress of OLED devices with high efficiency at high luminance

    Science.gov (United States)

    Nguyen, Carmen; Ingram, Grayson; Lu, Zhenghong

    2014-03-01

    Organic light emitting diodes (OLEDs) have progressed significantly over the last two decades. For years, OLEDs have been promoted as the next generation technology for flat panel displays and solid-state lighting due to their potential for high energy efficiency and dynamic range of colors. Although high efficiency can readily be obtained at low brightness levels, a significant decline at high brightness is commonly observed. In this report, we will review various strategies for achieving highly efficient phosphorescent OLED devices at high luminance. Specifically, we will provide details regarding the performance and general working principles behind each strategy. We will conclude by looking at how some of these strategies can be combined to produce high efficiency white OLEDs at high brightness.

  2. Improvements in or relating to semiconductor devices

    Energy Technology Data Exchange (ETDEWEB)

    Pepper, M

    1981-08-26

    A method of testing a field effect device for radiation hardness is described which does not involve irradiating the device. In a low temperature environment the conductance of the device is measured as a function of gate voltage at a first and at a second different substrate bias potential and by comparing the two an assessment of radiation hardness is made.

  3. Highly efficient red electrophosphorescent devices at high current densities

    International Nuclear Information System (INIS)

    Wu Youzhi; Zhu Wenqing; Zheng Xinyou; Sun, Runguang; Jiang Xueyin; Zhang Zhilin; Xu Shaohong

    2007-01-01

    Efficiency decrease at high current densities in red electrophosphorescent devices is drastically restrained compared with that from conventional electrophosphorescent devices by using bis(2-methyl-8-quinolinato)4-phenylphenolate aluminum (BAlq) as a hole and exciton blocker. Ir complex, bis(2-(2'-benzo[4,5-α]thienyl) pyridinato-N,C 3' ) iridium (acetyl-acetonate) is used as an emitter, maximum external quantum efficiency (QE) of 7.0% and luminance of 10000cd/m 2 are obtained. The QE is still as high as 4.1% at higher current density J=100mA/cm 2 . CIE-1931 co-ordinates are 0.672, 0.321. A carrier trapping mechanism is revealed to dominate in the process of electroluminescence

  4. Efficiency optimization of green phosphorescent organic light-emitting device

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jung Soo; Jeon, Woo Sik; Yu, Jae Hyung [Department of Information Display, Kyung Hee University, Dongdaemoon-gu, Seoul 130-701 (Korea, Republic of); Pode, Ramchandra, E-mail: rbpode@khu.ac.k [Department of Physics, Kyung Hee University, Dongdaemoon-gu, Seoul 130-701 (Korea, Republic of); Kwon, Jang Hyuk, E-mail: jhkwon@khu.ac.k [Department of Information Display, Kyung Hee University, Dongdaemoon-gu, Seoul 130-701 (Korea, Republic of)

    2011-03-01

    Using a narrow band gap host of bis[2-(2-hydroxyphenyl)-pyridine]beryllium (Bepp{sub 2}) and green phosphorescent Ir(ppy){sub 3} [fac-tris(2-phenylpyridine) iridium III] guest concentration as low as 2%, high efficiency phosphorescent organic light-emitting diode (PHOLED) is realized. Current and power efficiencies of 62.5 cd/A (max.), 51.0 lm/W (max.), and external quantum efficiency (max.) of 19.8% are reported in this green PHOLED. A low current efficiency roll-off value of 10% over the brightness of 10,000 cd/m{sup 2} is noticed in this Bepp{sub 2} single host device. Such a high efficiency is obtained by the optimization of the doping concentration with the knowledge of the hole trapping and the emission zone situations in this host-guest system. It is suggested that the reported device performance is suitable for applications in high brightness displays and lighting.

  5. Ultra-high Efficiency DC-DC Converter using GaN Devices

    DEFF Research Database (Denmark)

    Ramachandran, Rakesh

    2016-01-01

    properties of GaN devices can be utilized in power converters to make them more compact and highly efficient. This thesis entitled “Ultra-high Efficiency DC-DC Converter using GaN devices” focuses on achieving ultra-high conversion efficiency in an isolated dc-dc converter by the optimal utilization of Ga...... for many decades. However, the rate of improvement slowed as the silicon power materials asymptotically approached its theoretical bounds. Compared to Si, wideband gap materials such as Silicon Carbide (SiC) and Gallium Nitride (GaN) are promising semiconductors for power devices due to their superior...... in this thesis. Efficiency measurements from the hardware prototype of both the topologies are also presented in this thesis. Finally, the bidirectional operation of an optimized isolated dc-dc converter is presented. The optimized converter has achieved an ultra-high efficiency of 98.8% in both directions...

  6. Energy-Efficient Resource and Power Allocation for Underlay Multicast Device-to-Device Transmission

    Directory of Open Access Journals (Sweden)

    Fan Jiang

    2017-11-01

    Full Text Available In this paper, we present an energy-efficient resource allocation and power control scheme for D2D (Device-to-Device multicasting transmission. The objective is to maximize the overall energy-efficiency of D2D multicast clusters through effective resource allocation and power control schemes, while considering the quality of service (QoS requirements of both cellular users (CUs and D2D clusters. We first build the optimization model and a heuristic resource and power allocation algorithm is then proposed to solve the energy-efficiency problem with less computational complexity. Numerical results indicate that the proposed algorithm outperforms existing schemes in terms of throughput per energy consumption.

  7. The Image Transceiver Device: Studies of Improved Physical Design.

    Science.gov (United States)

    David, Yitzhak; Efron, Uzi

    2008-07-25

    The Image Transceiver Device (ITD) design is based on combining LCOS micro-display, image processing tools and back illuminated APS imager in single CMOS chip [1]. The device is under development for Head-Mounted Display applications in augmented and virtual reality systems. The main issues with the present design are a high crosstalk of the backside imager and the need to shield the pixel circuitry from the photocharges generated in the silicon substrate. In this publication we present a modified, "deep p-well" ITD pixel design, which provides a significantly reduced crosstalk level, as well as an effective shielding of photo-charges for the pixel circuitry. The simulation performed using Silvaco software [ATLAS Silicon Device Simulator, Ray Trace and Light Absorption programs, Silvaco International, 1998] shows that the new approach provides high photo response and allows increasing the optimal thickness of the die over and above the 10-15 micrometers commonly used for back illuminated imaging devices, thereby improving its mechanical ruggedness following the thinning process and also providing a more efficient absorption of the long wavelength photons. The proposed deep p-well pixel structure is also a technology solution for the fabrication of high performance back illuminated CMOS image sensors.

  8. The Image Transceiver Device: Studies of Improved Physical Design

    Directory of Open Access Journals (Sweden)

    Uzi Efron

    2008-07-01

    Full Text Available The Image Transceiver Device (ITD design is based on combining LCOS micro-display, image processing tools and back illuminated APS imager in single CMOS chip [1]. The device is under development for Head-Mounted Display applications in augmented and virtual reality systems. The main issues with the present design are a high crosstalk of the backside imager and the need to shield the pixel circuitry from the photocharges generated in the silicon substrate. In this publication we present a modified, “deep p-well” ITD pixel design, which provides a significantly reduced crosstalk level, as well as an effective shielding of photo-charges for the pixel circuitry. The simulation performed using Silvaco software [ATLAS Silicon Device Simulator, Ray Trace and Light Absorption programs, Silvaco International, 1998] shows that the new approach provides high photo response and allows increasing the optimal thickness of the die over and above the 10-15 micrometers commonly used for back illuminated imaging devices, thereby improving its mechanical ruggedness following the thinning process and also providing a more efficient absorption of the long wavelength photons. The proposed deep p-well pixel structure is also a technology solution for the fabrication of high performance back illuminated CMOS image sensors.

  9. Measures for energy efficiency improvement of buildings

    Directory of Open Access Journals (Sweden)

    Vukadinović Ana V.

    2015-01-01

    Full Text Available The increase in energy consumption in buildings causes the need to propose energy efficiency improvement measures. Urban planning in accordance with micro location conditions can lead to energy consumption reduction in buildings through the passive solar design. While satisfying the thermal comfort to the user space purpose, energy efficiency can be achieved by optimizing the architectural and construction parameters such as shape of the building, envelope structure and the percentage of glazing. The improvement of the proposed measures, including the use of renewable energy sources, can meet requirements of Directive 2010/31 / EU of 'nearly zero energy buildings'.

  10. Quantum entanglement helps in improving economic efficiency

    International Nuclear Information System (INIS)

    Du Jiangfeng; Ju Chenyong; Li Hui

    2005-01-01

    We propose an economic regulation approach based on quantum game theory for the government to reduce the abuses of oligopolistic competition. Theoretical analysis shows that this approach can help government improve the economic efficiency of the oligopolistic market, and help prevent monopoly due to incorrect information. These advantages are completely attributed to the quantum entanglement, a unique quantum mechanical character

  11. Improving biological efficiency of Oyster mushroom, Pleurotus ...

    African Journals Online (AJOL)

    International Journal of Biological and Chemical Sciences ... Yield improvement were observed in both pigeon pea and sunflower seed cake supplemented treatments with the highest mycelium vigor (91.65%) and biological ... Keywords: biological efficiency, compost, mycelium vigor, pigeon pea, sunflower seed cake

  12. Quantum entanglement helps in improving economic efficiency

    Science.gov (United States)

    Du, Jiangfeng; Ju, Chenyong; Li, Hui

    2005-02-01

    We propose an economic regulation approach based on quantum game theory for the government to reduce the abuses of oligopolistic competition. Theoretical analysis shows that this approach can help government improve the economic efficiency of the oligopolistic market, and help prevent monopoly due to incorrect information. These advantages are completely attributed to the quantum entanglement, a unique quantum mechanical character.

  13. Improving the Efficiency of Solid State Light Sources

    International Nuclear Information System (INIS)

    Joanna McKittrick

    2003-01-01

    This proposal addresses the national need to develop a high efficiency light source for general illumination applications. The goal is to perform research that would lead to the fabrication of a unique solid state, white-emitting light source. This source is based on an InGaN/GaN UV-emitting chip that activates a luminescent material (phosphor) to produce white light. White-light LEDs are commercially available which use UV from a GaN chip to excite a phosphor suspended in epoxy around the chip. Currently, these devices are relatively inefficient. This research will target one technical barrier that presently limits the efficiency of GaN based devices. Improvements in efficiencies will be achieved by improving the internal conversion efficiency of the LED die, by improving the coupling between the die and phosphor(s) to reduce losses at the surfaces, and by selecting phosphors to maximize the emissions from the LEDs in conversion to white light. The UCSD research team proposes for this project to develop new phosphors that have high quantum efficiencies that can be activated by the UV-blue (360-410 nm) light emitted by the GaN device. The main goal for the UCSD team was to develop new phosphor materials with a very specific property: phosphors that could be excited at long UV-wavelengths (λ=350-410 nm). The photoluminescence of these new phosphors must be activated with photons emitted from GaN based dies. The GaN diodes can be designed to emit UV-light in the same range (λ=350-410 nm). A second objective, which is also very important, is to search for alternate methods to fabricate these phosphors with special emphasis in saving energy and time and reduce pollution

  14. Improved rectilinear scanning device for the whole body

    International Nuclear Information System (INIS)

    Berninger, W.H.

    1975-01-01

    A rectilinear scanning device for whole-body counting is described in which the spacial resolution is considerably improved upon by using photomultipliers with spherically curved photocathodes. By this measure, the distinct non-linearity between the output signals of the phototubes and the actual position of the scintillation in the scintillation crystal, as observed in plane photocathodes, is removed. The distances between the photomultipliers and the scintillation crystal can thus be kept very small whereby an improved statistic and lower noise can be obtained. Furthermore, thicker crystals can be used whereby the efficiency in the determination of higher energies is increased. The electronic signal processing to the reproduction of the nuclide distribution in the body is described in detail. (ORU/LH) [de

  15. A novel electroluminescent PPV copolymer and silsesquioxane nanocomposite film for the preparation of efficient PLED devices.

    Science.gov (United States)

    Venegoni, Ivan; Carniato, Fabio; Olivero, Francesco; Bisio, Chiara; Pira, Nello Li; Lambertini, Vito Guido; Marchese, Leonardo

    2012-11-02

    Polymer light-emitting diodes (PLEDs) have attracted growing interest in recent years for their potential use in displays and lighting fields. Nevertheless, PLED devices have some disadvantages in terms of low optoelectronic efficiency, high cost, short lifetimes and low thermal stability, which limit their final applications. Huge efforts have been made recently to improve the performances of these devices. The addition of inorganic or hybrid organic-inorganic nanoparticles to the light-emitting polymers, for example, allows their thermal stability and electroluminescent efficiency to be increased. Following this approach, novel PLED devices based on composite films of PPV-derivative copolymer (commercial name Super Yellow, SY) and octaisobutil POSS, were developed in this study. The device containing Super Yellow loaded with 1 wt% of POSS showed higher efficiency (ca. +30%) and improved lifetime in comparison to PLED prepared with the pure electroluminescent polymer. The PLED devices developed in this study are suitable candidates for automotive dashboards and, in general, for lighting applications.

  16. The gain from improved market efficiency

    DEFF Research Database (Denmark)

    Ejrnæs, Mette; Persson, Karl Gunnar

    2010-01-01

    demand as well as excess supply, which triggered off the tâtonnement process. Over time, adjustments to equilibrium, as measured by the half-life of a shock, became faster and violations of the law of one price become smaller. There were significant gains from improved market efficiency, which took place......This article looks at the gains from improved market efficiency in long-distance grain trade in the second half of the nineteenth century, when violations of the law of one price were reduced due to improved information transmission. Two markets, a major export centre, Chicago, and a major importer......, Liverpool, are analysed. We show that the law of one price equilibrium was an ‘attractor equilibrium'. The implication is that prices converged to that equilibrium in a tâtonnement process. Because of asymmetrically timed information between markets separated by long distances there were periods of excess...

  17. Digital lingual orthodontics and temporary anchorage devices for efficient biomechanics

    Directory of Open Access Journals (Sweden)

    Pravin Shetty

    2016-01-01

    Full Text Available Adult patients seeking orthodontic treatment at all times present with an esthetic demand even during treatment. The lingual orthodontics, apart from its esthetic values, also presents several other advantages. Currently, it has become a complete system in itself, starting from an accurate diagnosis, treatment protocol, and laboratory procedure to placement of the appliance in the patient′s mouth. With the advent of computer-aided design/computer-aided manufacturing system, the lingual orthodontics is more evolved and made ease operators in respect to more efficient mechanics and reduced archwire adjustments. The present article presents two cases to show the efficiency of lingual orthodontics with temporary anchorage devices and anterior retraction hook.

  18. Investigation of Processing, Microstructures and Efficiencies of Polycrystalline CdTe Photovoltaic Films and Devices

    Science.gov (United States)

    Munshi, Amit Harenkumar

    with processes suitable for mass production. These are the highest efficiencies reported by any university or national laboratory for polycrystalline thin-film CdTe photovoltaics bettered only by researchers at First Solar Inc. Processing experiments are traditionally designed based on simulation results however in these study microscopic materials characterization has been used as the primary driving force to understand the effects of processing conditions. Every structure and efficiency reported in this study has been extensively studied using microscopic imaging and materials characterization and processing conditions accordingly altered to achieve higher efficiencies. Understanding CdCl2 passivation treatment out of this has been critical to this process. Several observations with regard to effect of CdCl 2 passivation have allowed the use to this treatment to achieve optimum performance. The effects of deposition temperature are also studied in rigorous details. All of these studies have played an important role in optimization of process that lead to high efficiency thin-film CdTe photovoltaic devices. An effort is made in this study to better understand and establish a 3-way relationship between processing conditions, film microstructure and device efficiency for sublimated thin-film CdTe photovoltaics. Some crucial findings include impact of grain size on efficiency of photovoltaic devices and improvement in fill-factor resulting from use of thicker CdTe absorber with larger grain size. An attempt is also made to understand the microstructure as the device efficiency improves from 1% efficiency to over 18% efficiency.

  19. Efficient light emitting devices based on phosphorescent partially doped emissive layers

    KAUST Repository

    Yang, Xiaohui; Jabbour, Ghassan E.

    2013-01-01

    We report efficient organic light emitting devices employing an ultrathin phosphor emissive layer. The electroluminescent spectra of these devices can be tuned by introducing a low-energy emitting phosphor layer into the emission zone. Devices

  20. Design of high efficiency and energy saving aeration device for aquaculture

    Science.gov (United States)

    Liu, Sibo

    2017-03-01

    Energy efficient aeration device for aquaculture, in line with "by more than a generation, dynamic aeration" train of thought for technical design and improvement. Removable aeration terminal as the core, multi-level water to improve the method, the mobile fading pore aeration, intelligent mobile and open and close as the main function, aimed at solving the existing pond aeration efficiency, low energy consumption is high, the function of a single problem. From energy saving, efficiency, biological bacteria on the three directions, the aquaculture industry of energy conservation and emissions reduction. Device of the main advantages are: 1, original mobile fading aerator on the one hand, to expand the scope of work, playing a micro porous aeration of dissolved oxygen with high efficiency and to achieve "by more than a generation", on the other hand, through the sports equipment, stir the mixture of water, the water surface of photosynthesis of plants rich in dissolved oxygen input parts of the tank, compared to the stillness of the aerator can be more fully dissolved oxygen.2, through the opening of the pressure sensor indirect control device, can make the equipment timely and stop operation, convenient in use at the same time avoid the waste of energy.3, the biofilm suspension in aeration terminal, can be accomplished by nitration of microbial multi-level water improvement, still can make biofilm increase rate of netting in the movement process, the biological and mechanical aerobic promote each other, improve the efficiency of both. In addition, the device has small power consumption, low cost of characteristics. And have a certain degree of technical barriers, have their own intellectual property rights, and high degree of product market demand, easily accepted by customers, has a very high popularization value.

  1. Improving the efficiency of aerodynamic shape optimization

    Science.gov (United States)

    Burgreen, Greg W.; Baysal, Oktay; Eleshaky, Mohamed E.

    1994-01-01

    The computational efficiency of an aerodynamic shape optimization procedure that is based on discrete sensitivity analysis is increased through the implementation of two improvements. The first improvement involves replacing a grid-point-based approach for surface representation with a Bezier-Bernstein polynomial parameterization of the surface. Explicit analytical expressions for the grid sensitivity terms are developed for both approaches. The second improvement proposes the use of Newton's method in lieu of an alternating direction implicit methodology to calculate the highly converged flow solutions that are required to compute the sensitivity coefficients. The modified design procedure is demonstrated by optimizing the shape of an internal-external nozzle configuration. Practically identical optimization results are obtained that are independent of the method used to represent the surface. A substantial factor of 8 decrease in computational time for the optimization process is achieved by implementing both of the design procedure improvements.

  2. Idaho Chemical Processing Plant Process Efficiency improvements

    International Nuclear Information System (INIS)

    Griebenow, B.

    1996-03-01

    In response to decreasing funding levels available to support activities at the Idaho Chemical Processing Plant (ICPP) and a desire to be cost competitive, the Department of Energy Idaho Operations Office (DOE-ID) and Lockheed Idaho Technologies Company have increased their emphasis on cost-saving measures. The ICPP Effectiveness Improvement Initiative involves many activities to improve cost effectiveness and competitiveness. This report documents the methodology and results of one of those cost cutting measures, the Process Efficiency Improvement Activity. The Process Efficiency Improvement Activity performed a systematic review of major work processes at the ICPP to increase productivity and to identify nonvalue-added requirements. A two-phase approach was selected for the activity to allow for near-term implementation of relatively easy process modifications in the first phase while obtaining long-term continuous improvement in the second phase and beyond. Phase I of the initiative included a concentrated review of processes that had a high potential for cost savings with the intent of realizing savings in Fiscal Year 1996 (FY-96.) Phase II consists of implementing long-term strategies too complex for Phase I implementation and evaluation of processes not targeted for Phase I review. The Phase II effort is targeted for realizing cost savings in FY-97 and beyond

  3. Barriers to improvements in energy efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, A.K.N.

    1991-10-01

    To promote energy-efficiency improvements, actions may be required at one or more levels -- from the lowest level of the consumer (residential, commercial, industrial, etc.) through the highest level of the global agencies. But barriers to the implementation of energy-efficiency improvements exist or can arise at all these levels. Taking up each one of these barriers in turn, the paper discusses specific measures that can contribute to overcoming the barriers. However, a one-barrier-one-measure approach must be avoided. Single barriers may in fact involve several sub-barriers. Also, combinations of measures are much more effective in overcoming barriers. In particular, combinations of measures that simultaneously overcome several barriers are most successful. The paper discusses the typology of barriers, explores their origin and suggests measures that by themselves or in combination with other measures, will overcome these barriers. Since most of the barriers dealt with can be found in the barriers'' literature, any originality in the paper lies in its systematic organization, synoptic view and holistic treatment of this issue. This paper is intended to initiate a comprehensive treatment of barriers, their origins and the measures that contribute to overcoming them. Hopefully, such a treatment will facilitate the implementation of energy-efficiency improvements involving a wide diversity of ever-changing energy end uses and consumer preferences.

  4. Barriers to improvements in energy efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, A.K.N.

    1991-10-01

    To promote energy-efficiency improvements, actions may be required at one or more levels -- from the lowest level of the consumer (residential, commercial, industrial, etc.) through the highest level of the global agencies. But barriers to the implementation of energy-efficiency improvements exist or can arise at all these levels. Taking up each one of these barriers in turn, the paper discusses specific measures that can contribute to overcoming the barriers. However, a one-barrier-one-measure approach must be avoided. Single barriers may in fact involve several sub-barriers. Also, combinations of measures are much more effective in overcoming barriers. In particular, combinations of measures that simultaneously overcome several barriers are most successful. The paper discusses the typology of barriers, explores their origin and suggests measures that by themselves or in combination with other measures, will overcome these barriers. Since most of the barriers dealt with can be found in the ``barriers`` literature, any originality in the paper lies in its systematic organization, synoptic view and holistic treatment of this issue. This paper is intended to initiate a comprehensive treatment of barriers, their origins and the measures that contribute to overcoming them. Hopefully, such a treatment will facilitate the implementation of energy-efficiency improvements involving a wide diversity of ever-changing energy end uses and consumer preferences.

  5. EFFICIENT USE OF BIOMASS IN IMPROVED COOKSTOVES

    Directory of Open Access Journals (Sweden)

    R. K. PAL

    2016-12-01

    Full Text Available Traditional biomass cookstoves have very low efficiency. The improved cookstoves have very high efficiency. These improved cookstoves with high efficiency saves biomass fuels. Biomass can be saved in case of rocket elbow cookstoves. The amount of biomass which can be saved in case of rocket elbow cookstoves is 65.88 MT. More biomass can be saved in case of gasifier fan cookstoves. The amount of biomass which can be saved is 155.71 MT. The pollutants like particulate matter, black carbon, carbon mono-oxide and carbon dioxide emission is lesser in case of rocket elbow cookstoves. The pollutants are least in case of gasifier fan cookstoves. The reduction in particulate matter, black carbon, carbon mono-oxide and carbon dioxide emission in gasifier fan cookstoves is 1.77 MT, 0.24 MT, 0.71 MT & 151.64 MT respectively in comparison to traditional cookstoves. Therefore indoor air pollution is greatly reduced in case of improved cookstoves especially in case of gasifier fan cookstoves as compared to traditional cookstoves.

  6. IMPROVING TACONITE PROCESSING PLANT EFFICIENCY BY COMPUTER SIMULATION, Final Report

    Energy Technology Data Exchange (ETDEWEB)

    William M. Bond; Salih Ersayin

    2007-03-30

    This project involved industrial scale testing of a mineral processing simulator to improve the efficiency of a taconite processing plant, namely the Minorca mine. The Concentrator Modeling Center at the Coleraine Minerals Research Laboratory, University of Minnesota Duluth, enhanced the capabilities of available software, Usim Pac, by developing mathematical models needed for accurate simulation of taconite plants. This project provided funding for this technology to prove itself in the industrial environment. As the first step, data representing existing plant conditions were collected by sampling and sample analysis. Data were then balanced and provided a basis for assessing the efficiency of individual devices and the plant, and also for performing simulations aimed at improving plant efficiency. Performance evaluation served as a guide in developing alternative process strategies for more efficient production. A large number of computer simulations were then performed to quantify the benefits and effects of implementing these alternative schemes. Modification of makeup ball size was selected as the most feasible option for the target performance improvement. This was combined with replacement of existing hydrocyclones with more efficient ones. After plant implementation of these modifications, plant sampling surveys were carried out to validate findings of the simulation-based study. Plant data showed very good agreement with the simulated data, confirming results of simulation. After the implementation of modifications in the plant, several upstream bottlenecks became visible. Despite these bottlenecks limiting full capacity, concentrator energy improvement of 7% was obtained. Further improvements in energy efficiency are expected in the near future. The success of this project demonstrated the feasibility of a simulation-based approach. Currently, the Center provides simulation-based service to all the iron ore mining companies operating in northern

  7. Particle collector scoops for improved exhaust in ''axisymmetric'' devices

    International Nuclear Information System (INIS)

    Conn, R.W.; Wolf, G.H.

    1987-11-01

    Application of particle collector scoops in front of the pumping ducts of axisymmetric divertor/magnetic limiter configurations is proposed. These scoops should enclose a significant fraction of the recycling particles. The resulting increase in natural particle pressure in front of the pumping ducts leads to an improved exhaust efficiency. This can permit an extension of the operational margin for density control. Alternatively, aiming at a prescribed exhaust flow in reactor-type devices such as INTOR, the pumping ducts could be reduced in aperture, leaving valuable space for other components. The lay-out of the proposed scheme depends on the heat load on the leading edge in front of the scoop and on the deflector in front of the pumping ducts. 14 refs., 5 figs

  8. New raw materials improve packing sealing efficiency

    International Nuclear Information System (INIS)

    Igel, B.; McKeague, L.

    2012-01-01

    End-users and OEM's using or manufacturing on/off and control valves expect a permanent and effective increase in service life together with an increased sealing capability while at the same time minimizing maintenance concerns. Developing materials which provide consistency and repeatability are essential characteristics to optimizing valve performance. “New Generation” materials and yarn allow us to meet this growing demand while complying with the requirements related to chemical purity and an increased level of safety to both plant workers and equipment in the nuclear environment. Through R&D initiatives and developments in new and improved raw materials; a new mechanical packing generation which optimizes friction coefficients and extended life cycle has been introduced to the industry. Lower friction values drastically optimize actuator effort and size improving efficiency for stem operation with significant improvements in flow control of fluids. Combined with new and improved procedures (installation, torque levels and consolidation recommendations), this new packing generation has provided significant improvement in the mechanical behavior of packing materials (independent tests carried out in collaboration with AECL and CETIM) this has provided the opportunity to develop successful Valve Enhancement Programs which offer improved efficiency, valve operation and repeatability. These NEW generation yarns are available with or without wire reinforcement depending on specific operating parameters and conditions. The purpose of this presentation is to demonstrate that new generation material(s). Which are available to the industry for AOV, MOV and Manual valves? - To highlight the steps taken in R&D and manufacturing contributing to the much improved yarns and finished packing products. - Comply and are designed to meet the stringent requirements in the nuclear industry - Simplify valve maintenance without risk to safety or performance - Increase service

  9. High efficiency solid-state sensitized heterojunction photovoltaic device

    KAUST Repository

    Wang, Mingkui

    2010-06-01

    The high molar extinction coefficient heteroleptic ruthenium dye, NaRu(4,4′-bis(5-(hexylthio)thiophen-2-yl)-2,2′-bipyridine) (4-carboxylic acid-4′-carboxylate-2,2′-bipyridine) (NCS) 2, exhibits certified 5% electric power conversion efficiency at AM 1.5 solar irradiation (100 mW cm-2) in a solid-state dye-sensitized solar cell using 2,2′,7,7′-tetrakis-(N,N-di-pmethoxyphenylamine)-9, 9′-spirobifluorene (spiro-MeOTAD) as the organic hole-transporting material. This demonstration elucidates a class of photovoltaic devices with potential for low-cost power generation. © 2010 Elsevier Ltd. All rights reserved.

  10. High efficiency solid-state sensitized heterojunction photovoltaic device

    KAUST Repository

    Wang, Mingkui; Liu, Jingyuan; Cevey-Ha, Ngoc-Le; Moon, Soo-Jin; Liska, Paul; Humphry-Baker, Robin; Moser, Jacques-E.; Grä tzel, Carole; Wang, Peng; Zakeeruddin, Shaik M.

    2010-01-01

    The high molar extinction coefficient heteroleptic ruthenium dye, NaRu(4,4′-bis(5-(hexylthio)thiophen-2-yl)-2,2′-bipyridine) (4-carboxylic acid-4′-carboxylate-2,2′-bipyridine) (NCS) 2, exhibits certified 5% electric power conversion efficiency at AM 1.5 solar irradiation (100 mW cm-2) in a solid-state dye-sensitized solar cell using 2,2′,7,7′-tetrakis-(N,N-di-pmethoxyphenylamine)-9, 9′-spirobifluorene (spiro-MeOTAD) as the organic hole-transporting material. This demonstration elucidates a class of photovoltaic devices with potential for low-cost power generation. © 2010 Elsevier Ltd. All rights reserved.

  11. Modeling of detective quantum efficiency considering scatter-reduction devices

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ji Woong; Kim, Dong Woon; Kim, Ho Kyung [Pusan National University, Busan (Korea, Republic of)

    2016-05-15

    The reduction of signal-to-noise ratio (SNR) cannot be restored and thus has become a severe issue in digital mammography.1 Therefore, antiscatter grids are typically used in mammography. Scatter-cleanup performance of various scatter-reduction devices, such as air gaps,2 linear (1D) or cellular (2D) grids,3, 4 and slot-scanning devices,5 has been extensively investigated by many research groups. In the present time, a digital mammography system with the slotscanning geometry is also commercially available.6 In this study, we theoretically investigate the effect of scattered photons on the detective quantum efficiency (DQE) performance of digital mammography detectors by using the cascaded-systems analysis (CSA) approach. We show a simple DQE formalism describing digital mammography detector systems equipped with scatter reduction devices by regarding the scattered photons as additive noise sources. The LFD increased with increasing PMMA thickness, and the amounts of LFD indicated the corresponding SF. The estimated SFs were 0.13, 0.21, and 0.29 for PMMA thicknesses of 10, 20, and 30 mm, respectively. While the solid line describing the measured MTF for PMMA with 0 mm was the result of least-squares of regression fit using Eq. (14), the other lines were simply resulted from the multiplication of the fit result (for PMMA with 0 mm) with the (1-SF) estimated from the LFDs in the measured MTFs. Spectral noise-power densities over the entire frequency range were not much changed with increasing scatter. On the other hand, the calculation results showed that the spectral noise-power densities increased with increasing scatter. This discrepancy may be explained by that the model developed in this study does not account for the changes in x-ray interaction parameters for varying spectral shapes due to beam hardening with increasing PMMA thicknesses.

  12. Improving energy efficiency in handheld biometric applications

    Science.gov (United States)

    Hoyle, David C.; Gale, John W.; Schultz, Robert C.; Rakvic, Ryan N.; Ives, Robert W.

    2012-06-01

    With improved smartphone and tablet technology, it is becoming increasingly feasible to implement powerful biometric recognition algorithms on portable devices. Typical iris recognition algorithms, such as Ridge Energy Direction (RED), utilize two-dimensional convolution in their implementation. This paper explores the energy consumption implications of 12 different methods of implementing two-dimensional convolution on a portable device. Typically, convolution is implemented using floating point operations. If a given algorithm implemented integer convolution vice floating point convolution, it could drastically reduce the energy consumed by the processor. The 12 methods compared include 4 major categories: Integer C, Integer Java, Floating Point C, and Floating Point Java. Each major category is further divided into 3 implementations: variable size looped convolution, static size looped convolution, and unrolled looped convolution. All testing was performed using the HTC Thunderbolt with energy measured directly using a Tektronix TDS5104B Digital Phosphor oscilloscope. Results indicate that energy savings as high as 75% are possible by using Integer C versus Floating Point C. Considering the relative proportion of processing time that convolution is responsible for in a typical algorithm, the savings in energy would likely result in significantly greater time between battery charges.

  13. Improving Light Outcoupling Efficiency for OLEDs with Microlens Array Fabricated on Transparent Substrate

    Directory of Open Access Journals (Sweden)

    Jun Wang

    2014-01-01

    Full Text Available Low light outcoupling efficiency restricts the wide application of organic light-emitting diodes in solid state light market although the internal quantum efficiency of the device could reach near to 100%. In order to improve the output efficiency, different kinds of microlens array on the substrate emission surface were designed and simulated using light tracing method. Simulation results indicate that the microlens array on the substrate could efficiently improve the light output efficiency and an enhancement of 1.8 could be obtained with optimized microlens structure design. The microlens array with semicircle shape using polymer material was fabricated on glass substrate by a facile approach. Finally, the organic device with microlens array substrate was manufactured and the light output of the device with surface microlens structure could increase to 1.64 times comparing with the device without microlens.

  14. Integrated hospital emergency care improves efficiency.

    Science.gov (United States)

    Boyle, A A; Robinson, S M; Whitwell, D; Myers, S; Bennett, T J H; Hall, N; Haydock, S; Fritz, Z; Atkinson, P

    2008-02-01

    There is uncertainty about the most efficient model of emergency care. An attempt has been made to improve the process of emergency care in one hospital by developing an integrated model. The medical admissions unit was relocated into the existing emergency department and came under the 4-hour target. Medical case records were redesigned to provide a common assessment document for all patients presenting as an emergency. Medical, surgical and paediatric short-stay wards were opened next to the emergency department. A clinical decision unit replaced the more traditional observation unit. The process of patient assessment was streamlined so that a patient requiring admission was fully clerked by the first attending doctor to a level suitable for registrar or consultant review. Patients were allocated directly to specialty on arrival. The effectiveness of this approach was measured with routine data over the same 3-month periods in 2005 and 2006. There was a 16.3% decrease in emergency medical admissions and a 3.9% decrease in emergency surgical admissions. The median length of stay for emergency medical patients was reduced from 7 to 5 days. The efficiency of the elective surgical services was also improved. Performance against the 4-hour target declined but was still acceptable. The number of bed days for admitted surgical and medical cases rose slightly. There was an increase in the number of medical outliers on surgical wards, a reduction in the number of incident forms and formal complaints and a reduction in income for the hospital. Integrated emergency care has the ability to use spare capacity within emergency care. It offers significant advantages beyond the emergency department. However, improved efficiency in processing emergency patients placed the hospital at a financial disadvantage.

  15. Tape write-efficiency improvements in CASTOR

    International Nuclear Information System (INIS)

    Murray, S; Bahyl, V; Cancio, G; Cano, E; Lo Presti, G; Lo Re, G; Ponce, S; Kotlyar, V

    2012-01-01

    The CERN Advanced STORage manager (CASTOR) is used to archive to tape the physics data of past and present physics experiments. For reasons of physical storage space, all of the tape resident data in CASTOR are repacked onto higher density tapes approximately every two years. Improving the performance of writing files smaller than 2GB to tape is essential in order to keep the time needed to repack all of the tape resident data within a period of no more than 1 year. This paper reports on the solution to writing efficiently to tape that is currently in its early deployment phases at CERN.

  16. Implantable photonic devices for improved medical treatments

    Science.gov (United States)

    Sheinman, Victor; Rudnitsky, Arkady; Toichuev, Rakhmanbek; Eshiev, Abdyrakhman; Abdullaeva, Svetlana; Egemkulov, Talantbek; Zalevsky, Zeev

    2014-10-01

    An evolving area of biomedical research is related to the creation of implantable units that provide various possibilities for imaging, measurement, and the monitoring of a wide range of diseases and intrabody phototherapy. The units can be autonomic or built-in in some kind of clinically applicable implants. Because of specific working conditions in the live body, such implants must have a number of features requiring further development. This topic can cause wide interest among developers of optical, mechanical, and electronic solutions in biomedicine. We introduce preliminary clinical trials obtained with an implantable pill and devices that we have developed. The pill and devices are capable of applying in-body phototherapy, low-level laser therapy, blue light (450 nm) for sterilization, and controlled injection of chemicals. The pill is also capable of communicating with an external control box, including the transmission of images from inside the patient's body. In this work, our pill was utilized for illumination of the sinus-carotid zone in dog and red light influence on arterial pressure and heart rate was demonstrated. Intrabody liver tissue laser ablation and nanoparticle-assisted laser ablation was investigated. Sterilization effect of intrabody blue light illumination was applied during a maxillofacial phlegmon treatment.

  17. Efficiency improvements in pipeline transportation systems

    Energy Technology Data Exchange (ETDEWEB)

    Banks, W. F.; Horton, J. F.

    1977-09-09

    This report identifies potential energy-conservative pipeline innovations that are most energy- and cost-effective and formulates recommendations for the R, D, and D programs needed to exploit those opportunities. From a candidate field of over twenty classes of efficiency improvements, eight systems are recommended for pursuit. Most of these possess two highly important attributes: large potential energy savings and broad applicability outside the pipeline industry. The R, D, and D program for each improvement and the recommended immediate next step are described. The eight technologies recommended for R, D, and D are gas-fired combined cycle compressor station; internally cooled internal combustion engine; methanol-coal slurry pipeline; methanol-coal slurry-fired and coal-fired engines; indirect-fired coal-burning combined-cycle pump station; fuel-cell pump station; drag-reducing additives in liquid pipelines; and internal coatings in pipelines.

  18. Energy efficiency improvement and environment in China

    International Nuclear Information System (INIS)

    Rouhier, Stephane

    2010-01-01

    Massive reliance on polluting sources of energy (coal, traditional biomass and oil) has damaged the environment in China over years. Now, China is the world's first carbon dioxide emitter and air pollution represents between 2 and 7 percent of loss of Gross Domestic Product per year, depending on the studies chosen. In order to reduce the level of pollution, one can either enhance the technology in use or reduce the share of polluting fuels in the energy mix. Indeed, current Chinese technologies are far less efficient than those of developed countries and the energy mix is massively composed of polluting sources of energy. So, they both represent huge potential savings. This article enquires the link between diversification, efficiency in the power sector and the per capita emissions and shows that emissions are negatively correlated to a diversification of the energy mix as well as an improvement of power generating technologies. Hence, it justifies the diversification of the energy mix and technology improvement as viable strategies to tackle pollution

  19. A Pareto-based multi-objective optimization algorithm to design energy-efficient shading devices

    International Nuclear Information System (INIS)

    Khoroshiltseva, Marina; Slanzi, Debora; Poli, Irene

    2016-01-01

    Highlights: • We present a multi-objective optimization algorithm for shading design. • We combine Harmony search and Pareto-based procedures. • Thermal and daylighting performances of external shading were considered. • We applied the optimization process to a residential social housing in Madrid. - Abstract: In this paper we address the problem of designing new energy-efficient static daylight devices that will surround the external windows of a residential building in Madrid. Shading devices can in fact largely influence solar gains in a building and improve thermal and lighting comforts by selectively intercepting the solar radiation and by reducing the undesirable glare. A proper shading device can therefore significantly increase the thermal performance of a building by reducing its energy demand in different climate conditions. In order to identify the set of optimal shading devices that allow a low energy consumption of the dwelling while maintaining high levels of thermal and lighting comfort for the inhabitants we derive a multi-objective optimization methodology based on Harmony Search and Pareto front approaches. The results show that the multi-objective approach here proposed is an effective procedure in designing energy efficient shading devices when a large set of conflicting objectives characterizes the performance of the proposed solutions.

  20. MPACT Subgroup Self-Shielding Efficiency Improvements

    International Nuclear Information System (INIS)

    Stimpson, Shane; Liu, Yuxuan; Collins, Benjamin S.; Clarno, Kevin T.

    2016-01-01

    Recent developments to improve the efficiency of the MOC solvers in MPACT have yielded effective kernels that loop over several energy groups at once, rather that looping over one group at a time. These kernels have produced roughly a 2x speedup on the MOC sweeping time during eigenvalue calculation. However, the self-shielding subgroup calculation had not been reevaluated to take advantage of these new kernels, which typically requires substantial solve time. The improvements covered in this report start by integrating the multigroup kernel concepts into the subgroup calculation, which are then used as the basis for further extensions. The next improvement that is covered is what is currently being termed as ''Lumped Parameter MOC''. Because the subgroup calculation is a purely fixed source problem and multiple sweeps are performed only to update the boundary angular fluxes, the sweep procedure can be condensed to allow for the instantaneous propagation of the flux across a spatial domain, without the need to sweep along all segments in a ray. Once the boundary angular fluxes are considered to be converged, an additional sweep that will tally the scalar flux is completed. The last improvement that is investigated is the possible reduction of the number of azimuthal angles per octant in the shielding sweep. Typically 16 azimuthal angles per octant are used for self-shielding and eigenvalue calculations, but it is possible that the self-shielding sweeps are less sensitive to the number of angles than the full eigenvalue calculation.

  1. Improving energy efficiency in the transportation sector

    Energy Technology Data Exchange (ETDEWEB)

    Plotkin, S.E.

    1994-12-31

    A primary characteristic of transportation in the United States is its high per capita energy consumption. The average US citizen consumes nearly five times as much energy for transportation as the average Japanese and nearly three times as much as the average citizen of France, Britain, or West Germany. The energy efficiency of US transportation has improved substantially over the past two decades (both absolutely and in comparison to Europe), and US travel volume has grown more slowly than in most of the developed world. However, the United States still consumes more than one-third of the world`s transport energy. Also, 96 percent of US transport energy is in the form of oil products. This is more oil than the United States produces, despite its position as one of the world`s largest oil producers. With current problems and expectation of continued growth in travel and energy use, Congress has increasingly turned to transportation energy conservation - in the form of improvements in the technical efficiency of travel, increases in load factors, reductions in travel demand, shifting to alternative fuels, and shifts to more efficient travel modes - as an important policy goal. For example, the Clean Air Amendments of 1990 incorporate transportation demand management as a critical tool in reducing urban air pollution. Legislation proposed in the 102d Congress sought rigorous new automobile and light truck fuel economy standards. With continued increases in U.S. oil imports, urban traffic congestion, and greenhouse gas emissions, and the failure of many urban areas to meet air quality standards, strong congressional interest in new energy conservation initiates is likely to continue.

  2. Engineering Strain for Improved III-Nitride Optoelectronic Device Performance

    Science.gov (United States)

    Van Den Broeck, Dennis Marnix

    Due to growing environmental and economic concerns, renewable energy generation and high-efficiency lighting are becoming even more important in the scientific community. III-Nitride devices have been essential in production of high-brightness light-emitting diodes (LEDs) and are now entering the photovoltaic (PV) realm as the technology advances. InGaN/GaN multiple quantum well LEDs emitting in the blue/green region have emerged as promising candidates for next-generation lighting technologies. Due to the large lattice mismatch between InN and GaN, large electric fields exist within the quantum well layers and result in low rates of radiative recombination, especially for the green spectral region. This is commonly referred to as the "green gap" and results in poor external quantum efficiencies for light-emitting diodes and laser diodes. In order to mitigate the compressive stress of InGaN QWs, a novel growth technique is developed in order to grown thick, strain-relaxed In yGa1-yN templates for 0.08 structure, "semibulk" InGaN templates were achieved with vastly superior crystal and optical properties than bulk InGaN films. These semibulk InGaN templates were then utilized as new templates for multiple quantum well active layers, effectively reducing the compressive strain in the InGaN wells due to the larger lattice constant of the InGaN template with respect to a GaN template. A zero-stress balance method was used in order to realize a strain-balanced multiple quantum well structure, which again showed improved optical characteristics when compared to fully-strain active regions. The semibulk InGaN template was then implemented into "strain-compensated" LED structures, where light emission was achieved with very little leakage current. Discussion of these strain-compensated devices compared to conventional LEDs is detailed.

  3. A New Microstructure Device for Efficient Evaporation of Liquids

    Science.gov (United States)

    Brandner, Juergen J.; Maikowske, Stefan; Vittoriosi, Alice

    Evaporation of liquids is of major interest for many topics in process engineering. One of these is chemical process engineering, where evaporation of liquids and generation of superheated steam is mandatory for numerous processes. Generally, this is performed by use of classical pool boiling and evaporation process equipment. Another possibility is creating mixtures of gases and liquids, combined with a heating of this haze. Both methods provide relatively limited performance. Due to the advantages of microstructure devices especially in chemical process engineering [1] the interest in microstructure evaporators and steam generators have been increased through the last decade. In this publication several microstructure devices used for evaporation and generation of steam as well as superheating will be described. Here, normally electrically powered devices containing micro channels as well as non-channel microstructures are used due to better controllability of the temperature level. Micro channel heat exchangers have been designed, manufactured and tested at the Institute for Micro Process Engineering of the Karlsruhe Institute of Technology for more than 15 years. Starting with the famous Karlsruhe Cube, a cross-flow micro channel heat exchanger of various dimensions, not only conventional heat transfer between liquids or gases have been theoretically and experimentally examined but also phase transition from liquids to gases (evaporation) and condensation of liquids. However, the results obtained with sealed microstructure devices have often been unsatisfying. Thus, to learn more onto the evaporation process itself, an electrically powered device for optical inspection of the microstructures and the processes inside has been designed and manufactured [2]. This was further optimized and improved for better controllability and reliable experiments [3]. Exchangeable metallic micro channel array foils as well as an optical inspection of the evaporation process by

  4. Investigating the Optimum Efficiency of Acoustoelectric Conversion Plate Devices

    Directory of Open Access Journals (Sweden)

    Chien-Chih Chen

    2014-04-01

    Full Text Available This study aims to develop the acoustoelectric conversion plate in terms of electromagnetic induction law to convert sound energy to electricity, where the developed apparatus is made of three parts, the thin film coil, the spring, and the high-intensity magnetic framework. In process, the thin film coil receives the injecting sound vibration in connection with the spring to cause the reciprocating motion between the coil and the high-intensity magnet, which yields the electromotive force (EMF. In this study, a pearl plate of length 95 mm, width 95 mm, and thickness 1.5 mm adhered with a PET film of thickness 0.08mm is built as the substrate plate due to it has good properties of light and elasticity. In connection with the substrate plate and the electric coil is the thin film coil. Experiments used the speaker with output frequencies of 30~156 Hz and sound power of 0.5 W (sound intensity 0.32 W/m2, sound pressure level 115 dB as the sound source. The sound energy is captured by the acoustoelectric conversion plate for working efficiency and optimization parameters analysis. The studied parameters content of diameter, turns, and width of electric coil as well as distance between high intensity magnet and coil. The results show that diameter 0.11 mm, turns 220, and width 3 mm of the electric coil, in connection with steel spring of diameter 0.2 mm while input sound is 30 Hz, receives the average output voltage of 0.57 V, the average output current of 5.46 mA, the average output power of 3.13 mW, and the sound electric conversion efficiency of 0.63%. This innovation device could be used in highway, near waterfalls, and some high noise factories to capture energy for immediately charging cell-phone to save human life.

  5. Optoelectronic devices, low temperature preparation methods, and improved electron transport layers

    KAUST Repository

    Eita, Mohamed S.

    2016-08-04

    An optoelectronic device such as a photovoltaic device which has at least one layer, such as an electron transport layer, which comprises a plurality of alternating, oppositely charged layers including metal oxide layers. The metal oxide can be zinc oxide. The plurality of layers can be prepared by layer-by-layer processing in which alternating layers are built up step-by-step due to electrostatic attraction. The efficiency of the device can be increased by this processing method compared to a comparable method like sputtering. The number of layers can be controlled to improve device efficiency. Aqueous solutions can be used which is environmentally friendly. Annealing can be avoided. A quantum dot layer can be used next to the metal oxide layer to form a quantum dot heterojunction solar device.

  6. Improving efficiency in the radiology department

    Energy Technology Data Exchange (ETDEWEB)

    Towbin, Alexander J.; Perry, Laurie A. [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Larson, David B. [Stanford University School of Medicine, Department of Radiology, Stanford, CA (United States)

    2017-06-15

    The modern radiology department is built around the flow of information. Ordering providers request imaging studies to be performed, technologists complete the work required to perform the imaging studies, and radiologists interpret and report on the imaging findings. As each of these steps is performed, data flow between multiple information systems, most notably the radiology information system (RIS), the picture archiving and communication system (PACS) and the voice dictation system. Even though data flow relatively seamlessly, the majority of our systems and processes are inefficient. The purpose of this article is to describe the radiology value stream and describe how radiology informaticists in one department have worked to improve the efficiency of the value stream at each step. Through these examples, we identify and describe several themes that we believe have been crucial to our success. (orig.)

  7. Efficiency comparison of 3 kinds of arterial puncture closing devices

    International Nuclear Information System (INIS)

    Feng Xiaodi; Jin Xian; Chen Yueguang; Xiao Hongbing; Yu Qiang; Chen Chengjun; Zhang Dadong

    2007-01-01

    Objective: To evaluate the efficiencies of arterial puncture closing devices (APCDs) including Angioseal, Perclose and Boomerang in patients undergone coronary angiography or percutaneous vascular interventions. Methods: 1497 patients underwent cardiac catheterization procedures were divided into manual compression group(639 cases) and APCDs closure group (576 cases with Angioseal, 151 cases Perclose and 11.3 cases of Boomerang). The times of maneuver, hemorrhage complication and other rare complications were assessed, recorded and compared. Results: The times for maneuver of standard manual compression group, Angioseal group, Perclose group and Boomerang group were (21.4±2.7) h, (3.5±2.3) h, (3.7± 2.6) h and (3.9±2.8) h respectively. The APCDs could obviously reduce bed rest time in comparing to that of manual compression. The rates of failure of the operations were 2.7%, 1.4%, 8.6% and 3.5% (P =0.006, P<0.001); and the rates of hemorrhage were 9.2%, 5.8%, 12.6% and 8.0% respectively for each of the four mentioned groups (P=0.005). Except the failure operations, the incidence of hemorrhage complications among the groups showed no significant differences. Conclusion: Application of APCDs to close the puncture site can significantly reduce the bed rest time, but not the incidence of hemorrhage complications. (authors)

  8. Efficient and Secure Fingerprint Verification for Embedded Devices

    Directory of Open Access Journals (Sweden)

    Sakiyama Kazuo

    2006-01-01

    Full Text Available This paper describes a secure and memory-efficient embedded fingerprint verification system. It shows how a fingerprint verification module originally developed to run on a workstation can be transformed and optimized in a systematic way to run real-time on an embedded device with limited memory and computation power. A complete fingerprint recognition module is a complex application that requires in the order of 1000 M unoptimized floating-point instruction cycles. The goal is to run both the minutiae extraction and the matching engines on a small embedded processor, in our case a 50 MHz LEON-2 softcore. It does require optimization and acceleration techniques at each design step. In order to speed up the fingerprint signal processing phase, we propose acceleration techniques at the algorithm level, at the software level to reduce the execution cycle number, and at the hardware level to distribute the system work load. Thirdly, a memory trace map-based memory reduction strategy is used for lowering the system memory requirement. Lastly, at the hardware level, it requires the development of specialized coprocessors. As results of these optimizations, we achieve a 65% reduction on the execution time and a 67% reduction on the memory storage requirement for the minutiae extraction process, compared against the reference implementation. The complete operation, that is, fingerprint capture, feature extraction, and matching, can be done in real-time of less than 4 seconds

  9. Efficient Device-Independent Entanglement Detection for Multipartite Systems

    Science.gov (United States)

    Baccari, F.; Cavalcanti, D.; Wittek, P.; Acín, A.

    2017-04-01

    Entanglement is one of the most studied properties of quantum mechanics for its application in quantum information protocols. Nevertheless, detecting the presence of entanglement in large multipartite states continues to be a great challenge both from the theoretical and the experimental point of view. Most of the known methods either have computational costs that scale inefficiently with the number of particles or require more information on the state than what is attainable in everyday experiments. We introduce a new technique for entanglement detection that provides several important advantages in these respects. First, it scales efficiently with the number of particles, thus allowing for application to systems composed by up to few tens of particles. Second, it needs only the knowledge of a subset of all possible measurements on the state, therefore being apt for experimental implementation. Moreover, since it is based on the detection of nonlocality, our method is device independent. We report several examples of its implementation for well-known multipartite states, showing that the introduced technique has a promising range of applications.

  10. Integrated Circuit Chip Improves Network Efficiency

    Science.gov (United States)

    2008-01-01

    Prior to 1999 and the development of SpaceWire, a standard for high-speed links for computer networks managed by the European Space Agency (ESA), there was no high-speed communications protocol for flight electronics. Onboard computers, processing units, and other electronics had to be designed for individual projects and then redesigned for subsequent projects, which increased development periods, costs, and risks. After adopting the SpaceWire protocol in 2000, NASA implemented the standard on the Swift mission, a gamma ray burst-alert telescope launched in November 2004. Scientists and developers on the James Webb Space Telescope further developed the network version of SpaceWire. In essence, SpaceWire enables more science missions at a lower cost, because it provides a standard interface between flight electronics components; new systems need not be custom built to accommodate individual missions, so electronics can be reused. New protocols are helping to standardize higher layers of computer communication. Goddard Space Flight Center improved on the ESA-developed SpaceWire by enabling standard protocols, which included defining quality of service and supporting plug-and-play capabilities. Goddard upgraded SpaceWire to make the routers more efficient and reliable, with features including redundant cables, simultaneous discrete broadcast pulses, prevention of network blockage, and improved verification. Redundant cables simplify management because the user does not need to worry about which connection is available, and simultaneous broadcast signals allow multiple users to broadcast low-latency side-band signal pulses across the network using the same resources for data communication. Additional features have been added to the SpaceWire switch to prevent network blockage so that more robust networks can be designed. Goddard s verification environment for the link-and-switch implementation continuously randomizes and tests different parts, constantly anticipating

  11. Enhanced pathway efficiency of Saccharomyces cerevisiae by introducing thermo-tolerant devices.

    Science.gov (United States)

    Liu, Yueqin; Zhang, Genli; Sun, Huan; Sun, Xiangying; Jiang, Nisi; Rasool, Aamir; Lin, Zhanglin; Li, Chun

    2014-10-01

    In this study, thermo-tolerant devices consisting of heat shock genes from thermophiles were designed and introduced into Saccharomyces cerevisiae for improving its thermo-tolerance. Among ten engineered thermo-tolerant yeasts, T.te-TTE2469, T.te-GroS2 and T.te-IbpA displayed over 25% increased cell density and 1.5-4-fold cell viability compared with the control. Physiological characteristics of thermo-tolerant strains revealed that better cell wall integrity, higher trehalose content and enhanced metabolic energy were preserved by thermo-tolerant devices. Engineered thermo-tolerant strain was used to investigate the impact of thermo-tolerant device on pathway efficiency by introducing β-amyrin synthesis pathway, showed 28.1% increased β-amyrin titer, 28-35°C broadened growth temperature range and 72h shortened fermentation period. The results indicated that implanting heat shock proteins from thermophiles to S. cerevisiae would be an efficient approach to improve its thermo-tolerance. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Efficient light emitting devices based on phosphorescent partially doped emissive layers

    KAUST Repository

    Yang, Xiaohui

    2013-05-29

    We report efficient organic light emitting devices employing an ultrathin phosphor emissive layer. The electroluminescent spectra of these devices can be tuned by introducing a low-energy emitting phosphor layer into the emission zone. Devices with the emissive layer consisting of multiple platinum-complex/spacer layer cells show a peak external quantum efficiency of 18.1%, which is among the best EQE values for platinum-complex based light emitting devices. Devices with an ultrathin phosphor emissive layer show stronger luminance decay with the operating time compared to the counterpart devices having a host-guest emissive layer.

  13. Experimental evaluation of cooling efficiency of the high performance cooling device

    Science.gov (United States)

    Nemec, Patrik; Malcho, Milan

    2016-06-01

    This work deal with experimental evaluation of cooling efficiency of cooling device capable transfer high heat fluxes from electric elements to the surrounding. The work contain description of cooling device, working principle of cooling device, construction of cooling device. Experimental part describe the measuring method of device cooling efficiency evaluation. The work results are presented in graphic visualization of temperature dependence of the contact area surface between cooling device evaporator and electronic components on the loaded heat of electronic components in range from 250 to 740 W and temperature dependence of the loop thermosiphon condenser surface on the loaded heat of electronic components in range from 250 to 740 W.

  14. Experimental evaluation of cooling efficiency of the high performance cooling device

    Energy Technology Data Exchange (ETDEWEB)

    Nemec, Patrik, E-mail: patrik.nemec@fstroj.uniza.sk; Malcho, Milan, E-mail: milan.malcho@fstroj.uniza.sk [University of Žilina, Faculty of Mechanical Engineering, Department of Power Engineering, Univerzitna 1, 010 26 Žilina (Slovakia)

    2016-06-30

    This work deal with experimental evaluation of cooling efficiency of cooling device capable transfer high heat fluxes from electric elements to the surrounding. The work contain description of cooling device, working principle of cooling device, construction of cooling device. Experimental part describe the measuring method of device cooling efficiency evaluation. The work results are presented in graphic visualization of temperature dependence of the contact area surface between cooling device evaporator and electronic components on the loaded heat of electronic components in range from 250 to 740 W and temperature dependence of the loop thermosiphon condenser surface on the loaded heat of electronic components in range from 250 to 740 W.

  15. Highly efficient hybrid energy generator: coupled organic photovoltaic device and randomly oriented electrospun poly(vinylidene fluoride) nanofiber.

    Science.gov (United States)

    Park, Boongik; Lee, Kihwan; Park, Jongjin; Kim, Jongmin; Kim, Ohyun

    2013-03-01

    A hybrid architecture consisting of an inverted organic photovoltaic device and a randomly-oriented electrospun PVDF piezoelectric device was fabricated as a highly-efficient energy generator. It uses the inverted photovoltaic device with coupled electrospun PVDF nanofibers as tandem structure to convert solar and mechanical vibrations energy to electricity simultaneously or individually. The power conversion efficiency of the photovoltaic device was also significantly improved up to 4.72% by optimized processes such as intrinsic ZnO, MoO3 and active layer. A simple electrospinning method with the two electrode technique was adopted to achieve a high voltage of - 300 mV in PVDF piezoelectric fibers. Highly-efficient HEG using voltage adder circuit provides the conceptual possibility of realizing multi-functional energy generator whenever and wherever various energy sources are available.

  16. A new device for vein localization and effect of application of disinfectant spray on its efficiency

    Directory of Open Access Journals (Sweden)

    Dreyer Jan

    2017-09-01

    Full Text Available A functional device was developed to immediately show the localization of veins by detecting a temperature increase on the skin directly above them. Our new idea, compared to other developments, is the comparison of temperatures between a small, ideally punctiform, skin area, and a larger circularly surrounding area. This is realized by two infrared temperature sensors, one with a small field of view, and the other one with a larger field of view. The position of the vein is indicated by two laser modules, which beams cross in one spot, when the device is held in a defined distance to the skin. If the device is held over a vein, the laser spot lightens up. The device was tested in ten study participants. Cooling of the skin by disinfectant spray prior to the measurements increases the temperature gradient and thereby improves the efficiency of the device. Temperature profiles of four skin areas of each study participant were measured before and one minute after application of disinfectant spray. After application of disinfectant spray, a temperature difference of more than 0.3 K between a measuring point above a vein and points 15 mm next to this could be found in 36 out of 40 measurements (90%, compared to 26 out of 40 (65% before disinfection. The mean temperature gradient could be increased from 0.476 K to 1.03 K (p < 0.001.

  17. Electroluminescent efficiency of alternating current thick film devices using ZnS:Cu,Cl phosphor

    International Nuclear Information System (INIS)

    Sharma, Gaytri; Han, Sang Do; Kim, Jung Duk; Khatkar, Satyender P.; Rhee, Young Woo

    2006-01-01

    ZnS:Cu,Cl phosphor is prepared with the help of low intensity milling of the precursor material in two step firing process. The synthesized phosphor is used for the preparation of alternating current thick film electroluminescent (ACTFEL) devices with screen-printing method. The commission international de l'Eclairge (CIE) color co-ordinates of the ACTFEL devices prepared by these phosphor layers shows a shift from bluish-green to green region with the change in the amount of Cu in the phosphor. The various parameters to improve the efficiency and luminance of the devices have also been investigated. The brightness of the ac thick film EL device depends on the particle size of the phosphor, crystallinity, amount of binding material and applied voltage. The EL device fabricated with phosphor having average particle size of 25 μm shows maximum luminescence, when 60% phosphor concentration is used with respect to binding material. EL intensity is also linearly dependent on frequency. It is due the increase of excitation chances of the host matrix or dopant ions with increasing frequency

  18. Improving the energy efficiency of mine fan assemblages

    International Nuclear Information System (INIS)

    De Souza, Euler

    2015-01-01

    Energy associated with ventilating an underground operation comprises a significant portion of a mine operation's base energy demand and is consequently responsible for a large percentage of the total operating costs. Ventilation systems may account from 25 to 40% of the total energy costs and 40–50% of the energy consumption of a mine operation. Fans are the most important mechanical devices used to ventilate underground mines and the total fan power installed in a single mine operation can easily exceed 10,000 kW. Investigations of a number of mine main fan installations have determined their assemblage to be, in general, very energy inefficient. The author has found that 40–80% of the energy consumed by a main fan is used to overcome the resistance of fan assemblage components. This paper presents how engineering design principles can be applied to improve the performance and efficiency of fan installations, resulting in substantial reductions in power consumption, operating cost and greenhouse gas emissions. A detailed case study is presented to demonstrate that, by designing fan assemblages using proper engineering concepts of fluid physics and industrial ventilation design, main fan systems will operate at efficiencies well above 80–90% (compared to common operating efficiencies of between 20 and 65%), resulting in a drastic reduction in a mine's overall costs and base electrical and energy loads. - Highlights: • Increases in fan assemblage efficiencies with minimum capital investment. • Improved designs for substantial fan power and operating cost savings. • General solutions and tactics for improving existing main fan installations. • Case study presented to demonstrate proper design of fan assemblages.

  19. Improved Power Conversion Efficiency of Inverted Organic Solar Cells by Incorporating Au Nanorods into Active Layer.

    Science.gov (United States)

    He, Yeyuan; Liu, Chunyu; Li, Jinfeng; Zhang, Xinyuan; Li, Zhiqi; Shen, Liang; Guo, Wenbin; Ruan, Shengping

    2015-07-29

    This Research Article describes a cooperative plasmonic effect on improving the performance of organic solar cells. When Au nanorods(NRs) are incorporated into the active layers, the designed project shows superior enhanced light absorption behavior comparing with control devices, which leads to the realization of organic solar cell with power conversion efficiency of 6.83%, accounting for 18.9% improvement. Further investigations unravel the influence of plasmonic nanostructures on light trapping, exciton generation, dissociation, and charge recombination and transport inside the thin films devices. Moreover, the introduction of high-conductivity Au NRs improves electrical conductivity of the whole device, which contributes to the enhanced fill factor.

  20. Efficiency improvement of thermal coal power plants

    Energy Technology Data Exchange (ETDEWEB)

    Hourfar, D. [VEBA Kraftwerke Ruhr Ag, Gelsenkirchen (Germany)

    1996-12-31

    The discussion concerning an increase of the natural greenhouse effect by anthropogenic changes in the composition of the atmosphere has increased over the past years. The greenhouse effect has become an issue of worldwide debate. Carbon dioxide is the most serious emission of the greenhouse gases. Fossil-fired power plants have in the recent past been responsible for almost 30 % of the total CO{sub 2} emissions in Germany. Against this background the paper will describe the present development of CO{sub 2} emissions from power stations and present actual and future opportunities for CO{sub 2} reduction. The significance attached to hard coal as one of today`s prime sources of energy with the largest reserves worldwide, and, consequently, its importance for use in power generation, is certain to increase in the years to come. The further development of conventional power plant technology, therefore, is vital, and must be carried out on the basis of proven operational experience. The main incentive behind the development work completed so far has been, and continues to be, the achievement of cost reductions and environmental benefits in the generation of electricity by increasing plant efficiency, and this means that, in both the short and the long term, power plants with improved conventional technology will be used for environmentally acceptable coal-fired power generation.

  1. Improving efficiency in bilateral emission trading

    International Nuclear Information System (INIS)

    Burtraw, D.; Harrison, K.W.; Turner, P.

    1998-01-01

    When environmental damages from emissions are spatially nonuniform, permit trading has been modeled most often as a 'pollution offset program' in which emission permits are traded between agents, subject to constraints on ambient air quality. To date the institution envisioned to implement such a program involves trading on a bilateral and sequential basis. However, simulation studies indicate that the sequence of trades may alter the outcome and undermine the cost savings from a pollution offset program. This paper identifies a design for the trading institution that tends to overcome this phenomenon and improve the efficiency of equilibria obtained in a simulation model. We model a bilateral trading process for the reduction of sulfur dioxide emissions with a stochastic description of the sequence of trades within groups of nations in Europe. When trading takes place between disaggregated, stylistic representations of economic enterprises, rather than between national governments, a significantly greater portion of potential savings is achieved. In fact, under most sets of assumptions, approximate first order stochastic dominance is achieved wherein the more decentralized the trading agents, the greater the expected savings from a trading program. 4 figs., 2 tabs., 31 refs

  2. Quasi-Resonant Absorption for Quantum Efficiency Improvement in Detectors

    Data.gov (United States)

    National Aeronautics and Space Administration — Quasi-resonant absorption has been demonstrated to enhance the quantum efficiency of devices across the spectrum, but specifically it is a challenge in the UV...

  3. Reliability and efficiency upgrades of power systems operation by implementing intelligent electronic devices with synchrophasor measurement technology support

    Directory of Open Access Journals (Sweden)

    Mokeev Alexey

    2017-01-01

    Full Text Available This paper reviews issues of reliability and efficiency upgrades of power systems functions by means of a widespread implementation of intelligent electronic devices (IED in various purposes supporting synchrophasor measurement technology. Thus, such issues as IED’s operational analysis in the conditions of electromagnetic and electromechanical transient processes and synthesis of digital filters that improve static and dynamic responses of these devices play an important role in their development.

  4. Reliability and efficiency upgrades of power systems operation by implementing intelligent electronic devices with synchrophasor measurement technology support

    OpenAIRE

    Mokeev Alexey

    2017-01-01

    This paper reviews issues of reliability and efficiency upgrades of power systems functions by means of a widespread implementation of intelligent electronic devices (IED) in various purposes supporting synchrophasor measurement technology. Thus, such issues as IED’s operational analysis in the conditions of electromagnetic and electromechanical transient processes and synthesis of digital filters that improve static and dynamic responses of these devices play an important role in their devel...

  5. Efficient fluorescent deep-blue and hybrid white emitting devices based on carbazole/benzimidazole compound

    KAUST Repository

    Yang, Xiaohui; Zheng, Shijun; Bottger, Rebecca; Chae, HyunSik; Tanaka, Takeshi; Li, Sheng; Mochizuki, Amane; Jabbour, Ghassan E.

    2011-01-01

    We report the synthesis, photophysics, and electrochemical characterization of carbazole/benzimidazole-based compound (Cz-2pbb) and efficient fluorescent deep-blue light emitting devices based on Cz-2pbb with the peak external quantum efficiency

  6. Efficient organic light-emitting devices with platinum-complex emissive layer

    KAUST Repository

    Yang, Xiaohui

    2011-01-18

    We report efficient organic light-emitting devices having a platinum-complex emissive layer with the peak external quantum efficiency of 17.5% and power efficiency of 45 lm W−1. Variation in the device performance with platinum-complex layer thickness can be attributed to the interplay between carrier recombination and intermolecular interactions in the layer. Efficient white devices using double platinum-complex layers show the external quantum efficiency of 10%, the Commission Internationale d’Énclairage coordinates of (0.42, 0.41), and color rendering index of 84 at 1000 cd m−2.

  7. Efficient organic light-emitting devices with platinum-complex emissive layer

    KAUST Repository

    Yang, Xiaohui; Wu, Fang-Iy; Haverinen, Hanna; Li, Jian; Cheng, Chien-Hong; Jabbour, Ghassan E.

    2011-01-01

    We report efficient organic light-emitting devices having a platinum-complex emissive layer with the peak external quantum efficiency of 17.5% and power efficiency of 45 lm W−1. Variation in the device performance with platinum-complex layer thickness can be attributed to the interplay between carrier recombination and intermolecular interactions in the layer. Efficient white devices using double platinum-complex layers show the external quantum efficiency of 10%, the Commission Internationale d’Énclairage coordinates of (0.42, 0.41), and color rendering index of 84 at 1000 cd m−2.

  8. Routes to Ultrahigh Efficiency Photovoltaic and Photoelectrochemical Devices

    Energy Technology Data Exchange (ETDEWEB)

    Eisler, Carissa; Lloyd, John; Flowers, Cris; Darbe, Sunita; Warmann, Emily; Verlage, Erik; Fountaine, Kate; Hu, Shu; Lewis, Nathan; Atwater, Harry

    2014-10-15

    We discuss ‘full spectrum’ photovoltaic modules that leverage low-cost III-V compound semiconductor cells, efficient optics and unconventional fabrication/assembly methods, and discuss advances in photoelectrochemical water-splitting with high efficiency.

  9. Energy sustainable development through energy efficient heating devices and buildings

    International Nuclear Information System (INIS)

    Bojic, M.

    2006-01-01

    Energy devices and buildings are sustainable if, when they operate, they use sustainable (renewable and refuse) energy and generate nega-energy. This paper covers three research examples of this type of sustainability: (1) use of air-to-earth heat exchangers, (2) computer control of heating and cooling of the building (via heat pumps and heat-recovery devices), and (3) design control of energy consumption in a house. (author)

  10. Efficiency Improvements of Antenna Optimization Using Orthogonal Fractional Experiments

    Directory of Open Access Journals (Sweden)

    Yen-Sheng Chen

    2015-01-01

    Full Text Available This paper presents an extremely efficient method for antenna design and optimization. Traditionally, antenna optimization relies on nature-inspired heuristic algorithms, which are time-consuming due to their blind-search nature. In contrast, design of experiments (DOE uses a completely different framework from heuristic algorithms, reducing the design cycle by formulating the surrogates of a design problem. However, the number of required simulations grows exponentially if a full factorial design is used. In this paper, a much more efficient technique is presented to achieve substantial time savings. By using orthogonal fractional experiments, only a small subset of the full factorial design is required, yet the resultant response surface models are still effective. The capability of orthogonal fractional experiments is demonstrated through three examples, including two tag antennas for radio-frequency identification (RFID applications and one internal antenna for long-term-evolution (LTE handheld devices. In these examples, orthogonal fractional experiments greatly improve the efficiency of DOE, thereby facilitating the antenna design with less simulation runs.

  11. Efficient Signature Based Malware Detection on Mobile Devices

    Directory of Open Access Journals (Sweden)

    Deepak Venugopal

    2008-01-01

    Full Text Available The threat of malware on mobile devices is gaining attention recently. It is important to provide security solutions to these devices before these threats cause widespread damage. However, mobile devices have severe resource constraints in terms of memory and power. Hence, even though there are well developed techniques for malware detection on the PC domain, it requires considerable effort to adapt these techniques for mobile devices. In this paper, we outline the considerations for malware detection on mobile devices and propose a signature based malware detection method. Specifically, we detail a signature matching algorithm that is well suited for use in mobile device scanning due to its low memory requirements. Additionally, the matching algorithm is shown to have high scanning speed which makes it unobtrusive to users. Our evaluation and comparison study with the well known Clam-AV scanner shows that our solution consumes less than 50% of the memory used by Clam-AV while maintaining a fast scanning rate.

  12. Charge transfer through amino groups-small molecules interface improving the performance of electroluminescent devices

    Science.gov (United States)

    Havare, Ali Kemal; Can, Mustafa; Tozlu, Cem; Kus, Mahmut; Okur, Salih; Demic, Şerafettin; Demirak, Kadir; Kurt, Mustafa; Icli, Sıddık

    2016-05-01

    A carboxylic group functioned charge transporting was synthesized and self-assembled on an indium tin oxide (ITO) anode. A typical electroluminescent device [modified ITO/TPD (50 nm)/Alq3 (60 nm)/LiF (2 nm)/(120 nm)] was fabricated to investigate the effect of the amino groups-small molecules interface on the characteristics of the device. The increase in the surface work function of ITO is expected to facilitate the hole injection from the ITO anode to the Hole Transport Layer (HTL) in electroluminescence. The modified electroluminescent device could endure a higher current and showed a much higher luminance than the nonmodified one. For the produced electroluminescent devices, the I-V characteristics, optical characterization and quantum yields were performed. The external quantum efficiency of the modified electroluminescent device is improved as the result of the presence of the amino groups-small molecules interface.

  13. Improved energy efficiency in sawmill drying system

    International Nuclear Information System (INIS)

    Anderson, Jan-Olof; Westerlund, Lars

    2014-01-01

    Highlights: • A heating system at a sawmill was investigated and improved. • Different impacts of external technologies at the energy usage were explored. • The heat and electricity consumption was analysed separate between technologies type. • The result point out a significant decrease of the biomass consumptions. - Abstract: The worldwide use of biomass has increased drastically during the last decade. At Swedish sawmills about half of the entering timber becomes lumber, with the remainder considered as by-product (biomass). A significant part of this biomass is used for internal heat production, mainly for forced drying of lumber in drying kilns. Large heat losses in kilns arise due to difficulties in recovering evaporative heat in moist air at low temperatures. This paper addresses the impact of available state-of-the-art technologies of heat recycling on the most common drying schemes used in Swedish sawmills. Simulations of different technologies were performed on an hourly basis to compare the heat and electricity demand with the different technologies. This was executed for a total sawmill and finally to the national level to assess the potential effects upon energy efficiency and biomass consumption. Since some techniques produce a surplus of heat the comparison has to include the whole sawmill. The impact on a national level shows the potential of the different investigated techniques. The results show that if air heat exchangers were introduced across all sawmills in Sweden, the heat demand would decrease by 0.3 TWh/year. The mechanical heat pump technology would decrease the heat demand by 5.6 TWh/year and would also produce a surplus for external heat sinks, though electricity demand would increase by 1 TWh/year. The open absorption system decreases the heat demand by 3.4 TWh/year on a national level, though at the same time there is a moderate increase in electricity demand of 0.05 TWh/year. Introducing actual energy prices in Sweden gives an

  14. Low-Cost, High Efficiency, Silicon Based Photovoltaic Devices

    Science.gov (United States)

    2015-08-27

    for photovoltaic applications. Figure 14: (a) Absorption and scattering efficiencies versus sizes of Au nanoparticle at 550 nm, (b) scattering...efficiency as a function of wavelength for different Au nanoparticles sizes . 32 Review of plasmonics light trapping for photovoltaic application...ensure that the irradiation variation was within 3%. The external quantum efficiency (EQE) system used a 300W Xenon light source with a spot size of 1mm

  15. Improving the efficiency of manuscript selection

    Directory of Open Access Journals (Sweden)

    A. Martínez–Abrain

    2009-01-01

    previous submittal were taken into account. Option b is suggested as an alternative to obliging authors to declare whether or not their submission was previously rejected by another journal, because they think this could prejudice the evaluation of the new submission. However, I believe that the system I propose here would prevent prejudiced evaluations because authors would have the opportunity to upload the response to reviewer’s comments so that second-round reviewers would have the chance to see both the problems previously de¬tected in the manuscript and the defence offered by authors. Although not a perfect system its benefits would probably outweigh the caveats. Such a system would improve the quality of the final paper and facilitate the work load for second–round reviewers and editors. Indeed, some journals already seem to be implementing a solution which is fairly similar to our proposal, asking authors of rejected papers for permission to forward reviewer reports to the new journal chosen by the authors to submit the revised work (see Hochberg et al., 2009. Proposals to reward or punish reviewers depending on their rapidity to elaborate their reports (Hauser & Fehr, 2007 does not foster accumulated quality improvement. Science quality would undoubtedly gain from making previous information concerning a manuscript’s review available to new reviewers, as in a Bayesian framework of inference (Martin et al., 2005 because starting a new each time, as if previous information did not exist, is simply not an efficient way to proceed in science.

  16. Efficiency evaluation test of waste non-destructive analysis device

    International Nuclear Information System (INIS)

    Maeda, Kouichi; Ogasawara, Kensuke; Nisizawa, Ichio

    2000-03-01

    A device for non-destructive analysis of plutonium in alpha solid waste has been installed in NUCEF; Nuclear Fuel Cycle Safety Engineering Research Facility. The device has been designed to determine the amount of radioisotopes in carton-boxes, 45 l steel cans and 200 l steel cans containing relatively low density waste. Considering the waste density and the heterogeneity of radio-sources, the proper distance between the detector and the waste, and the open degree of the collimator have been settled, because real waste may contain several kinds of material and the heterogeneity of radioactivity. It has been confirmed from the evaluation of the detect limit that plutonium of about 8 MBq can be determined with the accuracy of 10% and the device may be proper for the practical application. (author)

  17. Flow analysis for efficient design of wavy structured microchannel mixing devices

    Science.gov (United States)

    Kanchan, Mithun; Maniyeri, Ranjith

    2018-04-01

    Microfluidics is a rapidly growing field of applied research which is strongly driven by demands of bio-technology and medical innovation. Lab-on-chip (LOC) is one such application which deals with integrating bio-laboratory on micro-channel based single fluidic chip. Since fluid flow in such devices is restricted to laminar regime, designing an efficient passive modulator to induce chaotic mixing for such diffusion based flow is a major challenge. In the present work two-dimensional numerical simulation of viscous incompressible flow is carried out using immersed boundary method (IBM) to obtain an efficient design for wavy structured micro-channel mixing devices. The continuity and Navier-Stokes equations governing the flow are solved by fractional step based finite volume method on a staggered Cartesian grid system. IBM uses Eulerian co-ordinates to describe fluid flow and Lagrangian co-ordinates to describe solid boundary. Dirac delta function is used to couple both these co-ordinate variables. A tether forcing term is used to impose the no-slip boundary condition on the wavy structure and fluid interface. Fluid flow analysis by varying Reynolds number is carried out for four wavy structure models and one straight line model. By analyzing fluid accumulation zones and flow velocities, it can be concluded that straight line structure performs better mixing for low Reynolds number and Model 2 for higher Reynolds number. Thus wavy structures can be incorporated in micro-channels to improve mixing efficiency.

  18. Computationally efficient design of optimal output feedback strategies for controllable passive damping devices

    International Nuclear Information System (INIS)

    Kamalzare, Mahmoud; Johnson, Erik A; Wojtkiewicz, Steven F

    2014-01-01

    Designing control strategies for smart structures, such as those with semiactive devices, is complicated by the nonlinear nature of the feedback control, secondary clipping control and other additional requirements such as device saturation. The usual design approach resorts to large-scale simulation parameter studies that are computationally expensive. The authors have previously developed an approach for state-feedback semiactive clipped-optimal control design, based on a nonlinear Volterra integral equation that provides for the computationally efficient simulation of such systems. This paper expands the applicability of the approach by demonstrating that it can also be adapted to accommodate more realistic cases when, instead of full state feedback, only a limited set of noisy response measurements is available to the controller. This extension requires incorporating a Kalman filter (KF) estimator, which is linear, into the nominal model of the uncontrolled system. The efficacy of the approach is demonstrated by a numerical study of a 100-degree-of-freedom frame model, excited by a filtered Gaussian random excitation, with noisy acceleration sensor measurements to determine the semiactive control commands. The results show that the proposed method can improve computational efficiency by more than two orders of magnitude relative to a conventional solver, while retaining a comparable level of accuracy. Further, the proposed approach is shown to be similarly efficient for an extensive Monte Carlo simulation to evaluate the effects of sensor noise levels and KF tuning on the accuracy of the response. (paper)

  19. Safety and efficiency of emergency department interrogation of cardiac devices.

    Science.gov (United States)

    Neuenschwander, James F; Peacock, W Frank; Migeed, Madgy; Hunter, Sara A; Daughtery, John C; McCleese, Ian C; Hiestand, Brian C

    2016-12-01

    Patients with implanted cardiac devices may wait extended periods for interrogation in emergency departments (EDs). Our purpose was to determine if device interrogation could be done safely and faster by ED staff. Prospective randomized, standard therapy controlled, trial of ED staff device interrogation vs. standard process (SP), with 30-day follow-up. Eligibility criteria: ED presentation with a self-report of a potential device related complaint, with signed informed consent. SP interrogation was by company representative or hospital employee. Of 60 patients, 42 (70%) were male, all were white, with a median (interquartile range) age of 71 (64 to 82) years. No patient was lost to follow up. Of all patients, 32 (53%) were enrolled during business hours. The overall median (interquartile range) ED vs. SP time to interrogation was 98.5 (40 to 260) vs. 166.5 (64 to 412) minutes (P=0.013). While ED and SP interrogation times were similar during business hours, 102 (59 to 138) vs. 105 (64 to 172) minutes (P=0.62), ED interrogation times were shorter vs. SP during non-business hours; 97 (60 to 126) vs. 225 (144 to 412) minutes, P=0.002, respectively. There was no difference in ED length of stay between the ED and SP interrogation, 249 (153 to 390) vs. 246 (143 to 333) minutes (P=0.71), regardless of time of presentation. No patient in any cohort suffered an unplanned medical contact or post-discharge adverse device related event. ED staff cardiac device interrogations are faster, and with similar 30-day outcomes, as compared to SP.

  20. High efficiency rubrene based inverted top-emission organic light emitting devices with a mixed single layer

    International Nuclear Information System (INIS)

    Wang, Zhaokui; Lou, Yanhui; Naka, Shigeki; Okada, Hiroyuki

    2010-01-01

    Inverted top-emission organic light emitting devices (TEOLEDs) with a mixed single layer by mixing of electron transport materials (PyPySPyPy and Alq 3 ), hole transport material (α-NPD) and dope material (rubrene) were investigated. Maximum power efficiency of 3.5 lm/W and maximum luminance of 7000 cd/m 2 were obtained by optimizing the mixing ratio of PyPySPyPy:Alq 3 :α-NPD:rubrene=25:50:25:1. Luminance and power efficiency of mixed single layer device were two times improved compared to bi-layer heterojunction device and tri-layer heterojunction device. Lifetime test also shows that the mixed single layer device exhibits longer operational lifetimes of 343 h, which is three times longer than the 109 h for tri-layer device, and two times longer than the 158 h for bi-layer device. In addition, the maximum luminance and power efficiency were obtained at 20,000 cd/m 2 and 7.5 lm/W, respectively, when a TPD layer of 45 nm was capped onto the top metal electrode.

  1. Improving 200 MW NDHR reactor protection system with GAL devices

    International Nuclear Information System (INIS)

    Shi Mingde; Li Duo; Xie Zhengguo

    1999-01-01

    The emergence of General Array Logic (GAL), a fairly new type of logic devices with the characteristics of user-definable logic functions, have led to a revolutionary change in the design of logical circuits. The improvements of the reactor protection system for the 200 MW nuclear district heating reactor (NDHR) using GAL are covered

  2. New advances in wet scrubbing improvement efficiencies

    Energy Technology Data Exchange (ETDEWEB)

    Keen, A.R. [Altech Group, Toronto, ON (Canada)

    2000-07-01

    Wet scrubbing systems are the most versatile and cost efficient of all air pollution abatement technologies. This paper presented System REITHER{sup TM} which is a new generation of venturi scrubber. The advantages of this design are that it is simple and compact, has high removal efficiencies for sub-micron dusts or aerosols and it is flexible to handle any mass flow rate. It also provides high and constant reliability, is easy to control and has the potential to absorb gaseous pollutants. Another advantage is that it can handle corrosive streams through corrosion resistant materials. Innovations in wet scrubbing have made it possible to provide reliable and efficient separation of fine particles, corrosive aerosols and gases. New technology provides industrial engineers with a cost effective option when control air emissions is required. 1 fig.

  3. Enhancement of efficiencies for tandem green phosphorescent organic light-emitting devices with a p-type charge generation layer

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Byung Soo; Jeon, Young Pyo; Lee, Dae Uk; Kim, Tae Whan, E-mail: twk@hanayng.ac.kr

    2014-10-15

    The operating voltage of the tandem green phosphorescent organic light-emitting device with a 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile layer was improved by 3% over that of the organic light-emitting device with a molybdenum trioxide layer. The maximum brightness of the tandem green phosphorescent organic light-emitting device at 21.9 V was 26,540 cd/m{sup 2}. The dominant peak of the electroluminescence spectra for the devices was related to the fac-tris(2-phenylpyridine) iridium emission. - Highlights: • Tandem OLEDs with CGL were fabricated to enhance their efficiency. • The operating voltage of the tandem OLED with a HAT-CN layer was improved by 3%. • The efficiency and brightness of the tandem OLED were 13.9 cd/A and 26,540 cd/m{sup 2}. • Efficiency of the OLED with a HAT-CN layer was lower than that with a MoO{sub 3} layer. - Abstract: Tandem green phosphorescent organic light-emitting devices with a 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile or a molybdenum trioxide charge generation layer were fabricated to enhance their efficiency. Current density–voltage curves showed that the operating voltage of the tandem green phosphorescent organic light-emitting device with a 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile layer was improved by 3% over that of the corresponding organic light-emitting device with a molybdenum trioxide layer. The efficiency and the brightness of the tandem green phosphorescent organic light-emitting device were 13.9 cd/A and 26,540 cd/m{sup 2}, respectively. The current efficiency of the tandem green phosphorescent organic light-emitting device with a 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile layer was lower by 1.1 times compared to that of the corresponding organic light-emitting device with molybdenum trioxide layer due to the decreased charge generation and transport in the 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile layer resulting from triplet–triplet exciton annihilation.

  4. Approaches of Improving University Assets Management Efficiency

    Science.gov (United States)

    Wang, Jingliang

    2015-01-01

    University assets management, as an important content of modern university management, is generally confronted with the issue of low efficiency. Currently, to address the problems exposed in university assets management and take appropriate modification measures is an urgent issue in front of Chinese university assets management sectors. In this…

  5. Improved efficiency of organic light-emitting diodes based on a europium complex by fluorescent dye

    Energy Technology Data Exchange (ETDEWEB)

    You Han [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of Chinese Academy of Sciences, Changchun 130022 (China); Fang Junfeng [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of Chinese Academy of Sciences, Changchun 130022 (China); Gao Jia [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of Chinese Academy of Sciences, Changchun 130022 (China); Ma Dongge [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of Chinese Academy of Sciences, Changchun 130022 (China)]. E-mail: mdg1014@ciac.jl.cn

    2007-01-15

    Improved efficiency of organic light-emitting diodes (OLEDs) based on europium complexes have been realized by using a fluorescent dye 4-(dicyanomethylene)-2-t-butyl-6 (1,1,7,7-tetramethyljulolidyl-9-enyl))-4H-pyran (DCJTB) doping .The luminous efficiency of the devices with a fluorescent dye in the emissive layer was found to improve two times of that in devices without fluorescent dye. The devices showed pure red light, which is the characteristic emission of trivalent europium ion with a full-width at half-maximum of 3 nm.The maximum brightness and luminous efficiency reached 1200 cd/m{sup 2} at 23 V and 7.3 cd/A (2.0 lm/w), respectively, at a current density of 0.35 mA/cm{sup 2}.

  6. Hybrid VAR compensator with improved efficiency

    Directory of Open Access Journals (Sweden)

    V. V. Burlaka

    2015-03-01

    Full Text Available In modern electrical networks thyristor-switched capacitors (TSC are most used devices for VAR compensation. These devices don’t contain rotating parts and mechanical contacts, provide a stepwise control of reactive power and no generation of harmonics to the network. However, with the help of TSC it’s not possible to ensure smooth control of reactive power and capacitor banks (CB are exposed to the negative impact of higher harmonic components of the network voltage. Hybrid VAR compensator don’t have such drawbacks. It consists of active filter (AF and capacitor bank with discrete regulation. The main drawback of such systems is the necessity of accessing all six terminals of CB, while most of them are manufactured with three terminals, internally delta-connected. In the article, the topology and control system of hybrid VAR compensator free from beforementioned drawback, is proposed. The control system provides operating modes of overcompensation or undercompensation reactive power. VAR distribution regulator performs redistribution of reactive power between active filter and capacitor banks with the condition to minimize active filter’s power. Scheme of the hybrid VAR compensator, which includes a three-phase three-terminal delta-connected capacitor banks, is shown. Proposed approach allows to provide smooth control of reactive power, isolate the capacitor bank from harmonic currents and use a more effective low-voltage power components

  7. Improvement of fuel sampling device for STACY and TRACY

    International Nuclear Information System (INIS)

    Hirose, Hideyuki; Sakuraba, Koichi; Onodera, Seiji

    1998-05-01

    STACY and TRACY, static and transient experiment facilities in NUCEF, use solution fuel. It is important to analyze accurately fuel composition (uranium enrichment, uranium concentration, nitric acid morality, amount of impurities, radioactivity of FP) for their safety operation and improvement of experimental accuracy. Both STACY and TRACY have the sampling devices to sample fuel solution for that purpose. The previous sampling devices of STACY and TRACY had been designed to dilute fuel sample with nitric acid. Its sampling mechanism could pour fuel sample into sampling vessel by a piston drive of nitric acid in the burette. It was, however, sometimes found that sample fuel solution was diluted by mixing with nitric acid in the burette. Therefore, the sampling mechanism was change into a fixed quantity pump drive which didn't use nitric acid. The authors confirmed that the performance of the new sampling device was improved by changing sampling mechanism. It was confirmed through the function test that the uncertainty in uranium concentration measurement using the improved sampling device was 0.14%, and less than the designed value of 0.2% (coefficient of variation). (author)

  8. A magnetorheological clutch for efficient automotive auxiliary device actuation

    Directory of Open Access Journals (Sweden)

    F. Bucchi

    2013-01-01

    Full Text Available In this paper the results of a project funded by Regione Toscana aimed at reducing the power absorption of auxiliary devices in vehicles are presented. In particular the design, testing and application of a magnetorheological clutch (MR is proposed, aimed at disengaging the vacuum pump, which draws in air from the power-brake booster chamber, in order to reduce the device power absorption. Several clutch preliminary studies done to choose the clutch geometry and the magnetic field supply are illustrated. The final choice consisted in an MR clutch with permanent magnet, which satisfied size, torque and fail-safe specifications. The clutch characteristics, in terms of torque versus slip, were obtained experimentally for three different clutch prototypes on an ad-hoc developed test bench.As result of a preliminary simulation, a comparison between the power absorption of a current production vacuum pump, an innovative vacuum pump and both vacuum pumps coupled with the MR clutch is presented. The New European Driving Cycle is considered for simulating the vacuum pump operation both in urban and highway driving. Results show that the use of the innovative vacuum pump reduces the device consumption of about 35%, whereas the use of MR clutch coupled with the innovative vacuum pump reduces it up to about 44% in urban driving and 50% in highway driving.

  9. Improved waterflooding efficiency by horizontal wells

    Energy Technology Data Exchange (ETDEWEB)

    Popa, C. G. [Petroleum and Gas Univ., Ploesti (Romania); Clipea, M. [SNP Petrom SA, ICPT Campina (Romania)

    1998-12-31

    The influence of well pattern involving the use of horizontal wells on the overall efficiency of the waterflooding process was analyzed. Three different scenarios were examined: (1) a pattern of using two parallel horizontal wells, one for injection, the other for production, (2) a pattern of one horizontal well for water injection and several vertical wells for production, and (3) a pattern of using vertical wells for injection and one horizontal well for production. In each case, the waterflooding process was simulated using a two phase two dimensional numerical model. Results showed that the pressure loss along the horizontal section had a large influence on the sweep efficiency whether the horizontal well was used for injection or production. Overall, the most successful combination appeared to be using vertical wells for injection and horizontal wells for production. 4 refs., 1 tab., 15 figs.

  10. Loss Model and Efficiency Analysis of Tram Auxiliary Converter Based on a SiC Device

    Directory of Open Access Journals (Sweden)

    Hao Liu

    2017-12-01

    Full Text Available Currently, the auxiliary converter in the auxiliary power supply system of a modern tram adopts Si IGBT as its switching device and with the 1700 V/225 A SiC MOSFET module commercially available from Cree, an auxiliary converter using all SiC devices is now possible. A SiC auxiliary converter prototype is developed during this study. The author(s derive the loss calculation formula of the SiC auxiliary converter according to the system topology and principle and each part loss in this system can be calculated based on the device datasheet. Then, the static and dynamic characteristics of the SiC MOSFET module used in the system are tested, which aids in fully understanding the performance of the SiC devices and provides data support for the establishment of the PLECS loss simulation model. Additionally, according to the actual circuit parameters, the PLECS loss simulation model is set up. This simulation model can simulate the actual operating conditions of the auxiliary converter system and calculate the loss of each switching device. Finally, the loss of the SiC auxiliary converter prototype is measured and through comparison it is found that the loss calculation theory and PLECS loss simulation model is valuable. Furthermore, the thermal images of the system can prove the conclusion about loss distribution to some extent. Moreover, these two methods have the advantages of less variables and fast calculation for high power applications. The loss models may aid in optimizing the switching frequency and improving the efficiency of the system.

  11. Efficiency improvements of electromagnetic flow control

    International Nuclear Information System (INIS)

    Spong, E.; Reizes, J.A.; Leonardi, E.

    2005-01-01

    In turbulent flow, frictional resistance and heat transfer are controlled to a large degree by the intensity of the turbulence fluctuations in the near vicinity of a surface. In the case of a weak electrically conducting fluid, such as seawater, turbulence intensity can be controlled by subjecting the fluid to electromagnetic fields. This technique, known as Electro-magneto-hydro-dynamic (EMHD) flow control, has been shown to have promise as a means of reducing the turbulence intensity, and hence heat transfer or frictional drag of turbulent boundary layers. Unfortunately EMHD flow control currently suffers from poor efficiency due to the high energy requirements of the electromagnetic field. A numerical study has been conducted in which a new electromagnetic actuator design has been developed to provide a more efficient spatial distribution of the electromagnetic forces. The new actuator design has then been coupled to an ideal flow sensor. A flow control subroutine, embedded in the numerical model, uses the velocity information from the ideal sensor to determine the appropriate actuating force to apply to the flow at each time step. The new actuator design has been shown to be capable of successfully attenuating a sequence of artificial low speed streaks in a simplified model of a low Reynolds number turbulent boundary layer. Thus, a potential solution to the poor efficiency of EMHD flow control has been offered by providing the means whereby the expensive electromagnetic forces can be strategically and sparingly applied to the flow

  12. Improved energy efficiency in the process industries

    Energy Technology Data Exchange (ETDEWEB)

    Pilavachi, P A [Commission of the European Communities, Brussels (Belgium)

    1992-12-31

    The European Commission, through the JOULE Programme, is promoting energy efficient technologies in the process industries; the topics of the various R and D activities are: heat exchangers (enhanced evaporation, shell and tube heat exchangers including distribution of fluids, and fouling), low energy separation processes (adsorption, melt-crystallization and supercritical extraction), chemical reactors (methanol synthesis and reactors with integral heat exchangers), other unit operations (evaporators, glass-melting furnaces, cement kilns and baking ovens, dryers and packed columns and replacements for R12 in refrigeration), energy and system process models (batch processes, simulation and control of transients and energy synthesis), development of advanced sensors.

  13. Efficient Protection of Android Applications through User Authentication Using Peripheral Devices

    Directory of Open Access Journals (Sweden)

    Jinseong Kim

    2018-04-01

    Full Text Available Android applications store large amounts of sensitive information that may be exposed and exploited. To prevent this security risk, some applications such as Syrup and KakaoTalk use physical device values to authenticate or encrypt application data. However, by manipulating these physical device values, an attacker can circumvent the authentication by executing a Same Identifier Attack and obtain the same application privileges as the user. In our work, WhatsApp, KakaoTalk, Facebook, Amazon, and Syrup were subjected to the Same Identifier Attack, and it was found that an attacker could gain the same privileges as the user, in all five applications. To solve such a problem, we propose a technical scheme—User Authentication using Peripheral Devices. We applied the proposed scheme to a Nexus 5X smartphone running Android version 7.1 and confirmed that the average execution time was 0.005 s, which does not affect the other applications’ execution significantly. We also describe the security aspects of the proposed scheme and its compatibility with the Android platform and other applications. The proposed scheme is practical and efficient in terms of resource usage; therefore, it will be useful for Android users to improve Android application security.

  14. Efficient generation of hepatic cells from mesenchymal stromal cells by an innovative bio-microfluidic cell culture device.

    Science.gov (United States)

    Yen, Meng-Hua; Wu, Yuan-Yi; Liu, Yi-Shiuan; Rimando, Marilyn; Ho, Jennifer Hui-Chun; Lee, Oscar Kuang-Sheng

    2016-08-19

    Mesenchymal stromal cells (MSCs) are multipotent and have great potential in cell therapy. Previously we reported the differentiation potential of human MSCs into hepatocytes in vitro and that these cells can rescue fulminant hepatic failure. However, the conventional static culture method neither maintains growth factors at an optimal level constantly nor removes cellular waste efficiently. In addition, not only is the duration of differentiating hepatocyte lineage cells from MSCs required to improve, but also the need for a large number of hepatocytes for cell therapy has not to date been addressed fully. The purpose of this study is to design and develop an innovative microfluidic device to overcome these shortcomings. We designed and fabricated a microfluidic device and a culture system for hepatic differentiation of MSCs using our protocol reported previously. The microfluidic device contains a large culture chamber with a stable uniform flow to allow homogeneous distribution and expansion as well as efficient induction of hepatic differentiation for MSCs. The device enables real-time observation under light microscopy and exhibits a better differentiation efficiency for MSCs compared with conventional static culture. MSCs grown in the microfluidic device showed a higher level of hepatocyte marker gene expression under hepatic induction. Functional analysis of hepatic differentiation demonstrated significantly higher urea production in the microfluidic device after 21 days of hepatic differentiation. The microfluidic device allows the generation of a large number of MSCs and induces hepatic differentiation of MSCs efficiently. The device can be adapted for scale-up production of hepatic cells from MSCs for cellular therapy.

  15. Manufacture of Daily Check Device and Efficiency Evaluation for Daily Q.A

    International Nuclear Information System (INIS)

    Kim, Chan Yong; Jae, Young Wan; Park, Heung Deuk; Lee, Jae Hee

    2005-01-01

    Daily Q.A is the important step which must be preceded in a radiation treatment. Specially, radiation output measurement and laser alignment, SSD indicator related to a patient set-up recurrence must be confirmed for a reasonable radiation treatment. Daily Q.A proceeds correctness and a prompt way, and needs an objective measurement basis. Manufacture of the device which can facilitate confirmation of output measurement and appliances check at one time was requested. Produced the phantom formal daily check device which can confirm a lot of appliances check (output measurement and laser alignment. field size, SSD indicator) with one time of set up at a time, and measurement observed a linear accelerator (4 machine) for four months and evaluated efficiency. We were able to confirm an laser alignment, field size, SSD indicator check at the same time, and out put measurement was possible with the same set up, so daily Q.A time was reduced, and we were able to confirm an objective basis about each item measurement. As a result of having measured for four months, output measurement within ±2%, and measured laser alignment, field size, SSD indicator in range within ±1 mm. We can enforce output measurement and appliances check conveniently, and time was reduced and was able to raise efficiency of business. We were able to bring a cost reduction by substitution expensive commercialized equipment. Further It is necessary to makes a product as strong and slight materials, and improve convenience of use.

  16. Low-voltage and high-efficiency white organic light emitting devices with carrier balance

    International Nuclear Information System (INIS)

    Wei Fuxiang; Huang, Y.; Fang, L.

    2010-01-01

    White organic light emitting devices with the structure of ITO/m-MTDATA:x%4F-TCNQ/NPB/TBADN:EBDP:DCJTB/Bphen:Liq/LiF/Al have been demonstrated in this paper. High-mobility m-MTDATA:4F-TCNQ is added into the region between ITO and NBP to increase hole injection and transport. The high-mobility Bphen:Liq layer is added into the region between cathode and emission layers to lower cathode barrier and facilitate carrier injection. In the meanwhile, an effective carrier balance (number of holes is equal to number of electrons) between holes and electrons is considered to be one of the most important factors for improving OLEDs. During the experiment, by modulating the doping concentration of 4F-TCNQ, we can control hole injection and transport to make the carriers reach a high-level balance. The maximum current efficiency and power efficiency of devices were 9.3 cd/A and 4.6 lm/A, respectively.

  17. Efficient white organic light emitting devices with dual emitting layers

    International Nuclear Information System (INIS)

    Wu Yaoshan; Hwang Shiaowen; Chen Hsianhung; Lee Mengting; Shen Wenjian; Chen, C.H.

    2005-01-01

    In this paper, a new white organic light-emitting device (OLED) with the structure of indium tin oxide / CF x / 1,4-bis[N-(1-naphthyl)-N'-phenylamino]-biphenyl (NPB) (30 nm)/NPB: 2,8-di(t-butyl)-5,11-di[4-(t-butyl)phenyl]-6,12-diphenylnaphthacene (20 nm; 1.6 %) / 2-methyl-9,10-di(2-naphthyl) anthracene: p-bis(p-N,N-di-phenyl-aminostyryl)benzene (40 nm, 3%) / aluminum tris(8-hydroxyquinoline) (20 nm) / LiF (1 nm) / Al (200 nm) has been investigated. The device showed white emission with a high-luminous yield of 9.75 cd/A at 20 mA/cm 2 , but its Commission Internationale de l'Eclairage chromaticity coordinates appeared to change from (0.34, 0.42) at 6 mA/cm2 to (0.27, 0.37) at 200 mA/cm 2 due to the shift of recombination zone. The change of color with drive current was suppressed by introduction of an electron-blocking layer of NPB along with a hole-blocking layer of aluminum (III) bis(2-methyl-8-quinolinato)4-phenylphenolato to the white OLED which successfully confined the recombination site and achieved a luminous yield of 9.9 cd/A at 20 mA/cm 2

  18. Efficient white organic light emitting devices with dual emitting layers

    Energy Technology Data Exchange (ETDEWEB)

    Wu Yaoshan [Department of Applied Chemistry, National Chiao Tung University, Hsinchu, Taiwan, 30050 (China); Hwang Shiaowen [Display Institute, Microelectronics and Information Systems Research Center, National Chiao Tung University, Hsinchu, Taiwan, 30050 (China)]. E-mail: jesse@faculty.nctu.edu.tw; Chen Hsianhung [Department of Applied Chemistry, National Chiao Tung University, Hsinchu, Taiwan, 30050 (China); Lee Mengting [Department of Applied Chemistry, National Chiao Tung University, Hsinchu, Taiwan, 30050 (China); Shen Wenjian [Department of Applied Chemistry, National Chiao Tung University, Hsinchu, Taiwan, 30050 (China); Chen, C.H. [Display Institute, Microelectronics and Information Systems Research Center, National Chiao Tung University, Hsinchu, Taiwan, 30050 (China)

    2005-09-22

    In this paper, a new white organic light-emitting device (OLED) with the structure of indium tin oxide / CF {sub x} / 1,4-bis[N-(1-naphthyl)-N'-phenylamino]-biphenyl (NPB) (30 nm)/NPB: 2,8-di(t-butyl)-5,11-di[4-(t-butyl)phenyl]-6,12-diphenylnaphthacene (20 nm; 1.6 %) / 2-methyl-9,10-di(2-naphthyl) anthracene: p-bis(p-N,N-di-phenyl-aminostyryl)benzene (40 nm, 3%) / aluminum tris(8-hydroxyquinoline) (20 nm) / LiF (1 nm) / Al (200 nm) has been investigated. The device showed white emission with a high-luminous yield of 9.75 cd/A at 20 mA/cm{sup 2}, but its Commission Internationale de l'Eclairage chromaticity coordinates appeared to change from (0.34, 0.42) at 6 mA/cm2 to (0.27, 0.37) at 200 mA/cm{sup 2} due to the shift of recombination zone. The change of color with drive current was suppressed by introduction of an electron-blocking layer of NPB along with a hole-blocking layer of aluminum (III) bis(2-methyl-8-quinolinato)4-phenylphenolato to the white OLED which successfully confined the recombination site and achieved a luminous yield of 9.9 cd/A at 20 mA/cm{sup 2}.

  19. Improving quantum efficiency and spectral resolution of a CCD through direct manipulation of the depletion region

    Science.gov (United States)

    Brown, Craig; Ambrosi, Richard M.; Abbey, Tony; Godet, Olivier; O'Brien, R.; Turner, M. J. L.; Holland, Andrew; Pool, Peter J.; Burt, David; Vernon, David

    2008-07-01

    Future generations of X-ray astronomy instruments will require position sensitive detectors in the form of charge-coupled devices (CCDs) for X-ray spectroscopy and imaging with the ability to probe the X-ray universe with greater efficiency. This will require the development of CCDs with structures that will improve their quantum efficiency over the current state of the art. The quantum efficiency improvements would have to span a broad energy range (0.2 keV to >15 keV). These devices will also have to be designed to withstand the harsh radiation environments associated with orbits that extend beyond the Earth's magnetosphere. This study outlines the most recent work carried out at the University of Leicester focused on improving the quantum efficiency of an X-ray sensitive CCD through direct manipulation of the device depletion region. It is also shown that increased spectral resolution is achieved using this method due to a decrease in the number of multi-pixel events. A Monte Carlo and analytical models of the CCD have been developed and used to determine the depletion depths achieved through variation of the device substrate voltage, Vss. The models are also used to investigate multi-pixel event distributions and quantum efficiency as a function of depletion depth.

  20. Process improvement in healthcare: Overall resource efficiency

    NARCIS (Netherlands)

    de Mast, J.; Kemper, B.; Does, R.J.M.M.; Mandjes, M.; van der Bijl, Y.

    2011-01-01

    This paper aims to develop a unifying and quantitative conceptual framework for healthcare processes from the viewpoint of process improvement. The work adapts standard models from operation management to the specifics of healthcare processes. We propose concepts for organizational modeling of

  1. Method of making an improved superconducting quantum interference device

    International Nuclear Information System (INIS)

    Wu, C.T.; Falco, C.M.; Kampwirth, R.T.

    1977-01-01

    An improved superconducting quantum interference device is made by sputtering a thin film of an alloy of three parts niobium to one part tin in a pattern comprising a closed loop with a narrow region, depositing a thin film of a radiation shield such as copper over the niobium-tin, scribing a narrow line in the copper over the narrow region, exposing the structure at the scribed line to radiation and removing the deposited copper

  2. Efficient Parallel Strategy Improvement for Parity Games

    OpenAIRE

    Fearnley, John

    2017-01-01

    We study strategy improvement algorithms for solving parity games. While these algorithms are known to solve parity games using a very small number of iterations, experimental studies have found that a high step complexity causes them to perform poorly in practice. In this paper we seek to address this situation. Every iteration of the algorithm must compute a best response, and while the standard way of doing this uses the Bellman-Ford algorithm, we give experimental results that show that o...

  3. Improved light extraction from white organic light-emitting devices using a binary random phase array

    Energy Technology Data Exchange (ETDEWEB)

    Inada, Yasuhisa, E-mail: inada.yasuhisa@jp.panasonic.com; Nishiwaki, Seiji; Hirasawa, Taku; Nakamura, Yoshitaka; Hashiya, Akira; Wakabayashi, Shin-ichi; Suzuki, Masa-aki [R and D Division, Panasonic Corporation, 1006 Kadoma, Kadoma City, Osaka 571-8501 (Japan); Matsuzaki, Jumpei [Device Development Center, Eco Solutions Company, Panasonic Corporation, 1048 Kadoma, Osaka 571-8686 Japan (Japan)

    2014-02-10

    We have developed a binary random phase array (BRPA) to improve the light extraction performance of white organic light-emitting devices (WOLEDs). We demonstrated that the scattering of incoming light can be controlled by employing diffraction optics to modify the structural parameters of the BRPA. Applying a BRPA to the substrate of the WOLED leads to enhanced extraction efficiency and suppression of angle-dependent color changes. Our systematic study clarifies the effect of scattering on the light extraction of WOLEDs.

  4. Improved light extraction from white organic light-emitting devices using a binary random phase array

    International Nuclear Information System (INIS)

    Inada, Yasuhisa; Nishiwaki, Seiji; Hirasawa, Taku; Nakamura, Yoshitaka; Hashiya, Akira; Wakabayashi, Shin-ichi; Suzuki, Masa-aki; Matsuzaki, Jumpei

    2014-01-01

    We have developed a binary random phase array (BRPA) to improve the light extraction performance of white organic light-emitting devices (WOLEDs). We demonstrated that the scattering of incoming light can be controlled by employing diffraction optics to modify the structural parameters of the BRPA. Applying a BRPA to the substrate of the WOLED leads to enhanced extraction efficiency and suppression of angle-dependent color changes. Our systematic study clarifies the effect of scattering on the light extraction of WOLEDs

  5. Improvement of the Dehulling Efficiency of Sorghum and Millet using ...

    African Journals Online (AJOL)

    Conditioning of grain with heat and moisture is known to loosen the adhesion of the seed coat from the endosperm and therefore improve the dehulling efficiency of some grains such as beans, cowpea and canola. This study investigated the effect of hydrothermal treatment on the improvement of dehulling efficiency of ...

  6. Improving Reliability, Security, and Efficiency of Reconfigurable Hardware Systems (Habilitation)

    NARCIS (Netherlands)

    Ziener, Daniel

    2017-01-01

    In this treatise,  my research on methods to improve efficiency, reliability, and security of reconfigurable hardware systems, i.e., FPGAs, through partial dynamic reconfiguration is outlined. The efficiency of reconfigurable systems can be improved by loading optimized data paths on-the-fly on an

  7. Efficient Implementation of Solvers for Linear Model Predictive Control on Embedded Devices

    DEFF Research Database (Denmark)

    Frison, Gianluca; Kwame Minde Kufoalor, D.; Imsland, Lars

    2014-01-01

    This paper proposes a novel approach for the efficient implementation of solvers for linear MPC on embedded devices. The main focus is to explain in detail the approach used to optimize the linear algebra for selected low-power embedded devices, and to show how the high-performance implementation...

  8. Surface Operations Systems Improve Airport Efficiency

    Science.gov (United States)

    2009-01-01

    With Small Business Innovation Research (SBIR) contracts from Ames Research Center, Mosaic ATM of Leesburg, Virginia created software to analyze surface operations at airports. Surface surveillance systems, which report locations every second for thousands of air and ground vehicles, generate massive amounts of data, making gathering and analyzing this information difficult. Mosaic?s Surface Operations Data Analysis and Adaptation (SODAA) tool is an off-line support tool that can analyze how well the airport surface operation is working and can help redesign procedures to improve operations. SODAA helps researchers pinpoint trends and correlations in vast amounts of recorded airport operations data.

  9. On improving the efficiency of tensor voting.

    Science.gov (United States)

    Moreno, Rodrigo; Garcia, Miguel Angel; Puig, Domenec; Pizarro, Luis; Burgeth, Bernhard; Weickert, Joachim

    2011-11-01

    This paper proposes two alternative formulations to reduce the high computational complexity of tensor voting, a robust perceptual grouping technique used to extract salient information from noisy data. The first scheme consists of numerical approximations of the votes, which have been derived from an in-depth analysis of the plate and ball voting processes. The second scheme simplifies the formulation while keeping the same perceptual meaning of the original tensor voting: The stick tensor voting and the stick component of the plate tensor voting must reinforce surfaceness, the plate components of both the plate and ball tensor voting must boost curveness, whereas junctionness must be strengthened by the ball component of the ball tensor voting. Two new parameters have been proposed for the second formulation in order to control the potentially conflictive influence of the stick component of the plate vote and the ball component of the ball vote. Results show that the proposed formulations can be used in applications where efficiency is an issue since they have a complexity of order O(1). Moreover, the second proposed formulation has been shown to be more appropriate than the original tensor voting for estimating saliencies by appropriately setting the two new parameters.

  10. Energy efficiency improvement by gear shifting optimization

    Directory of Open Access Journals (Sweden)

    Blagojevic Ivan A.

    2013-01-01

    Full Text Available Many studies have proved that elements of driver’s behavior related to gear selection have considerable influence on the fuel consumption. Optimal gear shifting is a complex task, especially for inexperienced drivers. This paper presents an implemented idea for gear shifting optimization with the aim of fuel consumption minimization with more efficient engine working regimes. Optimized gear shifting enables the best possible relation between vehicle motion regimes and engine working regimes. New theoretical-experimental approach has been developed using On-Board Diagnostic technology which so far has not been used for this purpose. The matrix of driving modes according to which tests were performed is obtained and special data acquisition system and analysis process have been developed. Functional relations between experimental test modes and adequate engine working parameters have been obtained and all necessary operations have been conducted to enable their use as inputs for the designed algorithm. The created Model has been tested in real exploitation conditions on passenger car with Otto fuel injection engine and On-Board Diagnostic connection without any changes on it. The conducted tests have shown that the presented Model has significantly positive effects on fuel consumption which is an important ecological aspect. Further development and testing of the Model allows implementation in wide range of motor vehicles with various types of internal combustion engines.

  11. TIG welding power supply with improved efficiency

    Directory of Open Access Journals (Sweden)

    Сергій Володимирович Гулаков

    2015-03-01

    Full Text Available In the article, the influence of the DC component of the welding current during TIG (Tungsten Inert Gas welding is discussed. Known methods of DC current cancellation are reviewed, such as capacitor bank or diode/thyristor network insertion in the secondary circuit of the welding transformer. A new method of controlling the magnitude and shape of the TIG welding current is proposed. The idea is to insert a controlled voltage source in the secondary circuit of the welding transformer. This controlled voltage source is realized using a full-bridge voltage source inverter (VSI. VSI control system design issues are discussed. VSI is controlled by a three-level hysteretic current controller, while current reference is generated using lookup table driven by PLL (Phase Locked Loop locked to the mains frequency. Simulation results are shown. The proposed topology of TIG power supply allows to provide magnitude and shape control of the welding current, with the limitation that its DC component must be zero. Thus, some capabilities of professional AC-TIG welders are obtained using substantially lower cost components: VSI built using high-current low voltage MOSFETs with control system based on 32-bit ARM microcontroller. The use of proposed TIG welding power supply will eliminate the DC component of the welding current, improve welding transformer’s power factor and improve welding technology by increasing the welding arc stability

  12. Simulations of backgate sandwich nanowire MOSFETs with improved device performance

    International Nuclear Information System (INIS)

    Zhao Hengliang; Zhu Huilong; Zhong Jian; Ma Xiaolong; Wei Xing; Zhao Chao; Chen Dapeng; Ye Tianchun

    2014-01-01

    We propose a novel backgate sandwich nanowire MOSFET (SNFET), which offers the advantages of ETSOI (dynamic backgate voltage controllability) and nanowire FETs (good short channel effect). A backgate is used for threshold voltage (V t ) control of the SNFET. Compared with a backgate FinFET with a punch-through stop layer (PTSL), the SNFET possesses improved device performance. 3D device simulations indicate that the SNFET has a three times larger overdrive current, a ∼75% smaller off leakage current, and reduced subthreshold swing (SS) and DIBL than those of a backgate FinFET when the nanowire (NW) and the fin are of equal width. A new process flow to fabricate the backgate SNFET is also proposed in this work. Our analytical model suggests that V t control by the backgate can be attributed to the capacitances formed by the frontgate, NW, and backgate. The SNFET devices are compatible with the latest state-of-the-art high-k/metal gate CMOS technology with the unique capability of independent backgate control for nFETs and pFETs, which is promising for sub-22 nm scaling down. (semiconductor devices)

  13. Geospatial Technologies to Improve Urban Energy Efficiency

    Directory of Open Access Journals (Sweden)

    Bharanidharan Hemachandran

    2011-07-01

    Full Text Available The HEAT (Home Energy Assessment Technologies pilot project is a FREE Geoweb mapping service, designed to empower the urban energy efficiency movement by allowing residents to visualize the amount and location of waste heat leaving their homes and communities as easily as clicking on their house in Google Maps. HEAT incorporates Geospatial solutions for residential waste heat monitoring using Geographic Object-Based Image Analysis (GEOBIA and Canadian built Thermal Airborne Broadband Imager technology (TABI-320 to provide users with timely, in-depth, easy to use, location-specific waste-heat information; as well as opportunities to save their money and reduce their green-house-gas emissions. We first report on the HEAT Phase I pilot project which evaluates 368 residences in the Brentwood community of Calgary, Alberta, Canada, and describe the development and implementation of interactive waste heat maps, energy use models, a Hot Spot tool able to view the 6+ hottest locations on each home and a new HEAT Score for inter-city waste heat comparisons. We then describe current challenges, lessons learned and new solutions as we begin Phase II and scale from 368 to 300,000+ homes with the newly developed TABI-1800. Specifically, we introduce a new object-based mosaicing strategy, an adaptation of Emissivity Modulation to correct for emissivity differences, a new Thermal Urban Road Normalization (TURN technique to correct for scene-wide microclimatic variation. We also describe a new Carbon Score and opportunities to update city cadastral errors with automatically defined thermal house objects.

  14. Strategies for increasing the efficiency of heterojunction organic solar cells: material selection and device architecture.

    Science.gov (United States)

    Heremans, Paul; Cheyns, David; Rand, Barry P

    2009-11-17

    Thin-film blends or bilayers of donor- and acceptor-type organic semiconductors form the core of heterojunction organic photovoltaic cells. Researchers measure the quality of photovoltaic cells based on their power conversion efficiency, the ratio of the electrical power that can be generated versus the power of incident solar radiation. The efficiency of organic solar cells has increased steadily in the last decade, currently reaching up to 6%. Understanding and combating the various loss mechanisms that occur in processes from optical excitation to charge collection should lead to efficiencies on the order of 10% in the near future. In organic heterojunction solar cells, the generation of photocurrent is a cascade of four steps: generation of excitons (electrically neutral bound electron-hole pairs) by photon absorption, diffusion of excitons to the heterojunction, dissociation of the excitons into free charge carriers, and transport of these carriers to the contacts. In this Account, we review our recent contributions to the understanding of the mechanisms that govern these steps. Starting from archetype donor-acceptor systems of planar small-molecule heterojunctions and solution-processed bulk heterojunctions, we outline our search for alternative materials and device architectures. We show that non-planar phthalocynanines have appealing absorption characteristics but also have reduced charge carrier transport. As a result, the donor layer needs to be ultrathin, and all layers of the device have to be tuned to account for optical interference effects. Using these optimization techniques, we illustrate cells with 3.1% efficiency for the non-planar chloroboron subphthalocyanine donor. Molecules offering a better compromise between absorption and carrier mobility should allow for further improvements. We also propose a method for increasing the exciton diffusion length by converting singlet excitons into long-lived triplets. By doping a polymer with a

  15. Discontinuous interleaving of parallel inverters for efficiency improvement

    DEFF Research Database (Denmark)

    Rannestad, Bjørn; Munk-Nielsen, Stig; Gadgaard, Kristian

    2017-01-01

    Interleaved switching of parallel inverters has previously been proposed for efficiency/size improvements of grid connected three-phase inverters. This paper proposes a novel interleaving method which practically eliminates insulated gate bipolar transistor (IGBT) turn-on losses and drastically...... overall power module losses are reduced. The modulation strategy is suited for converters with doubly fed induction generators (DFIG) for wind turbines, but are not limited hereto. Improvement of switching performance are measured and operational efficiency improvements are calculated and verified...

  16. Demonstrating EnTracked a System for Energy-Efficient Position Tracking for Mobile Devices

    DEFF Research Database (Denmark)

    Kjærgaard, Mikkel Baun; Jensen, Jakob Langdal; Godsk, Torben

    An important feature of a modern mobile device is that it can position itself. Not only for use on the device but also for remote applications that require tracking of the device. To be useful, such position tracking has to be energy-efficient to avoid having a major impact on the battery life...... of the mobile device. To address this challenge we have build a system named EnTracked that, based on the estimation and prediction of system conditions and mobility, schedules position updates to both minimize energy consumption and optimize robustness. In this demonstration we would like to show how...

  17. Study of efficiency and current use of respiratory protective devices

    International Nuclear Information System (INIS)

    Linauskas, S.H.; Kalos, F.

    1984-12-01

    The efficiency of a helmet-type powered air-purifying respirator was studied in the work environment of an underground uranium mine. Workplace protection factors (WPF) were measured, using approximately 30-minute air sampling periods and repeated sampling throughout the work shifts for six miners during three shifts each. The WPF of the modified Racal AH-5 helmet was 17.8 (geometric mean) with new filters in the respirator; the WPF dropped to 5.3 when four-day-old filters were used. The WPF results were lognormally distributed. The test population appeared to be a homogeneous set: there was no significant difference in the mean WPFs of individual test subjects. The study could not resolve any effect of elapsed time within the work shift or of ambient Working Level on the WPF. The actual use levels and the problems associated with respirator use were studied at the same time, principally via a user survey. The respirators have a high level of acceptance among the user population of underground uranium miners and 72.5 percent of the 207 survey respondents stated six or more hours use with the visor in the correct 'down' position per shift

  18. Highly efficient tandem organic light-emitting devices employing an easily fabricated charge generation unit

    Science.gov (United States)

    Yang, Huishan; Yu, Yaoyao; Wu, Lishuang; Qu, Biao; Lin, Wenyan; Yu, Ye; Wu, Zhijun; Xie, Wenfa

    2018-02-01

    We have realized highly efficient tandem organic light-emitting devices (OLEDs) employing an easily fabricated charge generation unit (CGU) combining 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile with ultrathin bilayers of CsN3 and Al. The charge generation and separation processes of the CGU have been demonstrated by studying the differences in the current density-voltage characteristics of external-carrier-excluding devices. At high luminances of 1000 and 10000 cd/m2, the current efficiencies of the phosphorescent tandem device are about 2.2- and 2.3-fold those of the corresponding single-unit device, respectively. Simultaneously, an efficient tandem white OLED exhibiting high color stability and warm white emission has also been fabricated.

  19. Improvement in chest compression quality using a feedback device (CPRmeter): a simulation randomized crossover study.

    Science.gov (United States)

    Buléon, Clément; Parienti, Jean-Jacques; Halbout, Laurent; Arrot, Xavier; De Facq Régent, Hélène; Chelarescu, Dan; Fellahi, Jean-Luc; Gérard, Jean-Louis; Hanouz, Jean-Luc

    2013-10-01

    Cardiac arrest survival depends on celerity and efficiency of life support action. Guidelines emphasized the chest compression (CC) quality and feedback devices are encouraged. The purpose is to study the impact of the CPRmeter feedback device on resuscitation performed by untrained rescuers. This is a prospective randomized crossover study on manikins (Resusci Anne). One hundred and forty four students inexperienced in cardiopulmonary resuscitation representing untrained rescuers were included. Participants performed 2 minutes of CC without interruption with (group G) or without (group B) feedback. Four months passed between the 2 crossover phases to avoid resilience effect. Data collected by the CPRmeter device were: CC rate, depth and release. Efficient CC rate ([simultaneous and correct CC rate, depth and release] primary outcome) (absolute difference [95% CI]) was significantly improved in group G (71%) compared to group B (26%; [45 {36-55}]; P 38 mm) was significantly improved in group G (85%) compared to group B (43%; [42 {33-52}]; P < .0001). Adequate CC rate (90-120/min) was significantly improved in group G (81%) compared to group B (56%; [25 {15-35}]; P < .0001). The average CC rate and depth in group G were significantly less dispersed around the mean compared to group B (test of variance P < .007; P < .015 respectively). The use of the CPRmeter significantly improved CC quality performed by students inexperienced in cardiopulmonary resuscitation. © 2013.

  20. Nanoscale Dimples for Improved Absorption in and Efficiency of Organic Solar Cells

    DEFF Research Database (Denmark)

    Goszczak, Arkadiusz Jaroslaw; Adam, Jost; Cielecki, Pawel Piotr

    Organic solar cells (OSC’s) have attracted much attention in the past years due to their low costs, light weight and mechanical flexibility. A promising method for improving the power conversion efficiencies of the devices is by incorporating structured electrodes in the solar cell architecture....... That way light absorption in the active layers of the devices can be improved. A cheap and large-scale production compatible method for structuring the electrodes in OSC’s is by the use of Anodic Alumina Oxide (AAO) membranes. Here, nano-scale pores of controlled dimensions are formed through anodic...

  1. Efficiency Intra-Cluster Device-to-Device Relay Selection for Multicast Services Based on Combinatorial Auction

    Directory of Open Access Journals (Sweden)

    Yong Zhang

    2015-12-01

    Full Text Available In Long Term Evolution-Advanced (LTE-A networks, Device-to-device (D2D communications can be utilized to enhance the performance of multicast services by leveraging D2D relays to serve nodes with worse channel conditions within a cluster. For traditional D2D relay schemes, D2D links with poor channel condition may be the bottleneck of system sum data rate. In this paper, to optimize the throughput of D2D communications, we introduce an iterative combinatorial auction algorithm for efficient D2D relay selection. In combinatorial auctions, the User Equipments (UEs that fails to correctly receive multicast data from eNodeB (eNB are viewed as bidders that compete for D2D relays, while the eNB is treated as the auctioneer. We also give properties of convergency and low-complexity and present numerical simulations to verify the efficiency of the proposed algorithm.

  2. Energy efficiency comparison of forced-air versus resistance heating devices for perioperative hypothermia management

    International Nuclear Information System (INIS)

    Bayazit, Yilmaz; Sparrow, Ephraim M.

    2010-01-01

    Hypothermia is a state in which the temperature of a human body is below the normal temperature, with the onset of the hypothermic state commonly regarded as 36 o C. This state may be encountered due to exposure to a very cold environment in the outdoors or, surprisingly, in a hospital operating room. In the latter situation, the diminution of metabolic heat generation, coupled with moderate temperatures in the surroundings and absence of a covering over the afflicted parts of the body, creates the possibility of hypothermia. There are several available devices that are designed to ward off the onset of hypothermia. These currently most frequently used devices can be placed in two categories: (a) convective air warming and (b) direct-contact heat conduction. The warming principles that underlie these two approaches are distinctly different. Furthermore, the energy efficiencies of the two approaches differ significantly. The energy penalty which results from these different efficiencies may be compounded by the fact that the portion of the input energies to these devices which escapes into the operating room ambient must be extracted to maintain a comfortable temperature for the surgical staff. Since energy-extracting equipments such as air-conditioning machines are far from being perfectly efficient, the heat-extraction process also introduces wasted energy. Experiments were performed to determine the energy-utilization efficiencies of the representative devices in the two categories cited above. This information, taken together with the known efficiencies of air-conditioning machines, enabled an overall efficiency encompassing both the therapeutic device and the heat-extraction device to be calculated. The experimental data revealed that the specifics of individual devices within a category played a larger role with regard to energy efficiency than did the category itself.

  3. Energy efficiency comparison of forced-air versus resistance heating devices for perioperative hypothermia management

    Energy Technology Data Exchange (ETDEWEB)

    Bayazit, Yilmaz; Sparrow, Ephraim M. [Laboratory for Heat Transfer and Fluid Flow Practice, Department of Mechanical Engineering, University of Minnesota, 111 Church Street, SE, Minneapolis, MN 55455-0111 (United States)

    2010-03-15

    Hypothermia is a state in which the temperature of a human body is below the normal temperature, with the onset of the hypothermic state commonly regarded as 36 C. This state may be encountered due to exposure to a very cold environment in the outdoors or, surprisingly, in a hospital operating room. In the latter situation, the diminution of metabolic heat generation, coupled with moderate temperatures in the surroundings and absence of a covering over the afflicted parts of the body, creates the possibility of hypothermia. There are several available devices that are designed to ward off the onset of hypothermia. These currently most frequently used devices can be placed in two categories: (a) convective air warming and (b) direct-contact heat conduction. The warming principles that underlie these two approaches are distinctly different. Furthermore, the energy efficiencies of the two approaches differ significantly. The energy penalty which results from these different efficiencies may be compounded by the fact that the portion of the input energies to these devices which escapes into the operating room ambient must be extracted to maintain a comfortable temperature for the surgical staff. Since energy-extracting equipments such as air-conditioning machines are far from being perfectly efficient, the heat-extraction process also introduces wasted energy. Experiments were performed to determine the energy-utilization efficiencies of the representative devices in the two categories cited above. This information, taken together with the known efficiencies of air-conditioning machines, enabled an overall efficiency encompassing both the therapeutic device and the heat-extraction device to be calculated. The experimental data revealed that the specifics of individual devices within a category played a larger role with regard to energy efficiency than did the category itself. (author)

  4. Superefficient Refrigerators: Opportunities and Challenges for Efficiency Improvement Globally

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Nihar; Park, Won Young; Bojda, Nicholas; McNeil, Michael A.

    2014-08-01

    As an energy-intensive mainstream product, residential refrigerators present a significant opportunity to reduce electricity consumption through energy efficiency improvements. Refrigerators expend a considerable amount of electricity during normal use, typically consuming between 100 to 1,000 kWh of electricity per annum. This paper presents the results of a technical analysis done for refrigerators in support of the Super-efficient Equipment and Appliance Deployment (SEAD) initiative. Beginning from a base case representative of the average unit sold in India, we analyze efficiency improvement options and their corresponding costs to build a cost-versus-efficiency relationship. We then consider design improvement options that are known to be the most cost effective and that can improve efficiency given current design configurations. We also analyze and present additional super-efficient options, such as vacuum-insulated panels. We estimate the cost of conserved electricity for the various options, allowing flexible program design for market transformation programs toward higher efficiency. We estimate ~;;160TWh/year of energy savings are cost effective in 2030, indicating significant potential for efficiency improvement in refrigerators in SEAD economies and China.

  5. Enhanced quantum efficiency in blue-emitting polymer/dielectric nanolayer nanocomposite light-emitting devices

    International Nuclear Information System (INIS)

    Park, Jong Hyeok; Lim, Yong Taik; Park, O Ok; Yu, Jae-Woong; Kim, Jai Kyeong; Kim, Young Chul

    2004-01-01

    Light-emitting devices based on environmentally stable, blue-emitting polymer/dielectric nanolayer nanocomposites were fabricated by blending poly(di-octylfluorene) (PDOF) with organo-clay. By reducing the excimer formation that leads to long wavelength tails, the photoluminescence (PL) and electroluminescence (EL) color purity of the device was enhanced. When a conjugated polymer/dielectric nanolayer nanocomposite is applied to an EL device, we expect an electronic structure similar to the well-known quantum well in small nanodomains. The ratio of PDOF/organo-clay was regulated from 2:1 to 0.5:1 (w/w). The light-emitting device of 0.5:1 (w/w) blend demonstrated the highest quantum efficiency (QE), 0.72% (ph/el), which is ∼500 times higher value compared with that of the pure PDOF layer device. However, the driving voltage of the nanocomposite devices tended to increase with increasing organo-clay content

  6. The Multiple Benefits of Measures to Improve Energy Efficiency

    DEFF Research Database (Denmark)

    Puig, Daniel; Farrell, Timothy Clifford

    Understanding the barriers to, and enablers for, energy efficiency requires targeted information and analysis. This report is a summary of four detailed studies providing new insights on how to promote efficiency in selected priority areas. It complements initiatives such as the so-called energy...... efficiency accelerators, which seek to increase the uptake of selected technologies, as well as the work of many other institutions committed to improving energy efficiency. The modelling estimates and the case studies presented in this report illustrate that, while significant progress has already been...... achieved, the case for accelerating energy efficiency action is strong. Key highlights include: • At the global level, energy efficiency improvements would account for between 2.6 and 3.3 Gt CO2e of the reductions in 2030, equivalent to between 23 and 26 percent of the overall reductions achieved...

  7. Thermal efficiency improvements - an imperative for nuclear generating stations

    International Nuclear Information System (INIS)

    Hassanien, S.; Rouse, S.

    1997-01-01

    A one and a half percent thermal performance improvement of Ontario Hydro's operating nuclear units (Bruce B, Pickering B, and Darlington) means almost 980 GWh are available to the transmission system (assuming an 80% capacity factor). This is equivalent to the energy consumption of 34,000 electrically-heated homes in Ontario, and worth more than $39 million in revenue to Ontario Hydro Nuclear Generation. Improving nuclear plant thermal efficiency improves profitability (more GWh per unit of fuel) and competitiveness (cost of unit energy), and reduces environmental impact (less spent fuel and nuclear waste). Thermal performance will naturally decrease due to the age of the units unless corrective action is taken. Most Ontario Hydro nuclear units are ten to twenty years old. Some common causes for loss of thermal efficiency are: fouling and tube plugging of steam generators, condensers, and heat exchangers; steam leaks in the condenser due to valve wear, steam trap and drain leaks; deposition, pitting, cracking, corrosion, etc., of turbine blades; inadequate feedwater metering resulting from corrosion and deposition. This paper stresses the importance of improving the nuclear units' thermal efficiency. Ontario Hydro Nuclear has demonstrated energy savings results are achievable and affordable. Between 1994 and 1996, Nuclear reduced its energy use and improved thermal efficiency by over 430,000 MWh. Efficiency improvement is not automatic - strategies are needed to be effective. This paper suggests practical strategies to systematically improve thermal efficiency. (author)

  8. Does Automation Improve Stock Market Efficiency? Evidence from Ghana

    OpenAIRE

    Mensah, Justice T.; Pomaa-Berko, Maame; Adom, Philip Kofi

    2012-01-01

    As a burgeoning capital market in an emerging economy, automation of the stock market is regarded as a major step towards integrating the financial market as a conduit for economic growth. The automation of the Ghana Stock Exchange (GSE) in 2008 is expected among other things to improve the efficiency of the market. This paper therefore investigates the impact of the automation on the efficiency of the GSE within the framework of the weak-form Efficient Market Hypothesis (EMH) using daily mar...

  9. A history of industrial statistics and quality and efficiency improvement

    NARCIS (Netherlands)

    de Mast, J.; Coleman, S.; Greenfield, T.; Stewardson, D.; Montgomery, D.C.

    2008-01-01

    The twentieth century witnessed incredible increases in product quality, while in the same period product priced dropped dramatically. These important improvements in quality and efficiency in industry were the result of innovations in management and engineering. But these developments were

  10. Melatonin improves spermatogonial stem cells transplantation efficiency in azoospermic mice

    Directory of Open Access Journals (Sweden)

    Mohammadreza Gholami

    2014-02-01

    Conclusion: Administration of melatonin (20 mg/kg simultaneously with transplantation of spermatogonial stem cells in azoospermia mouse testis increases the efficiency of transplantation and improves structural properties of the testes tissue.

  11. Improvement in light-extraction efficiency of light emitting diode ...

    Indian Academy of Sciences (India)

    The effect of various microlens parameters such as diameter and area fraction on light-extraction efficiency was systematically studied. Improvement of 4% in extraction efficiency was obtained by employing it on white light emitting diode. The area fraction of microlenses was increased up to 0.34 by reducing the spin speed.

  12. Does automation improve stock market efficiency in Ghana ...

    African Journals Online (AJOL)

    The automation of the Ghana Stock Exchange (GSE) in 2008, among other reforms, was expected to improve the efficiency of the market. The extent of this truism has, however, not been empirically established for the GSE. In this study, we attempt to assess the impact of the automation on the efficiency of the GSE within the ...

  13. Refractories for Industrial Processing. Opportunities for Improved Energy Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Hemrick, James G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hayden, H. Wayne [Metals Manufacture Process and Controls Technology, Inc., Oak Ridge, TN (United States); Angelini, Peter [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Moore, Robert E. [R.E. Moore Associates, Maricopa, AZ (United States); Headrick, William L. [R.E. Moore Associates, Maricopa, AZ (United States)

    2005-01-01

    Refractories are a class of materials of critical importance to manufacturing industries with high-temperature unit processes. This study describes industrial refractory applications and identifies refractory performance barriers to energy efficiency for processing. The report provides recommendations for R&D pathways leading to improved refractories for energy-efficient manufacturing and processing.

  14. Platform for efficient switching between multiple devices in the intensive care unit.

    Science.gov (United States)

    De Backere, F; Vanhove, T; Dejonghe, E; Feys, M; Herinckx, T; Vankelecom, J; Decruyenaere, J; De Turck, F

    2015-01-01

    This article is part of the Focus Theme of METHODS of Information in Medicine on "Managing Interoperability and Complexity in Health Systems". Handheld computers, such as tablets and smartphones, are becoming more and more accessible in the clinical care setting and in Intensive Care Units (ICUs). By making the most useful and appropriate data available on multiple devices and facilitate the switching between those devices, staff members can efficiently integrate them in their workflow, allowing for faster and more accurate decisions. This paper addresses the design of a platform for the efficient switching between multiple devices in the ICU. The key functionalities of the platform are the integration of the platform into the workflow of the medical staff and providing tailored and dynamic information at the point of care. The platform is designed based on a 3-tier architecture with a focus on extensibility, scalability and an optimal user experience. After identification to a device using Near Field Communication (NFC), the appropriate medical information will be shown on the selected device. The visualization of the data is adapted to the type of the device. A web-centric approach was used to enable extensibility and portability. A prototype of the platform was thoroughly evaluated. The scalability, performance and user experience were evaluated. Performance tests show that the response time of the system scales linearly with the amount of data. Measurements with up to 20 devices have shown no performance loss due to the concurrent use of multiple devices. The platform provides a scalable and responsive solution to enable the efficient switching between multiple devices. Due to the web-centric approach new devices can easily be integrated. The performance and scalability of the platform have been evaluated and it was shown that the response time and scalability of the platform was within an acceptable range.

  15. A treatment of thermal efficiency improvement in the Brayton cycle

    International Nuclear Information System (INIS)

    Fujii, Terushige; Akagawa, Koji; Nakanishi, Shigeyasu; Inoue, Kiyoshi; Ishigai, Seikan.

    1982-01-01

    So far, as the working fluid for power-generating plants, mainly water and air (combustion gas) have been used. In this study, in regeneration and isothermal compression processes being considered as the means for the efficiency improvement in Brayton cycle, the investigation of equivalent graphical presentation method with T-S diagrams, the introduction of the new characteristic number expressing the possibility of thermal efficiency improvement by regeneration, and the investigation of the effect of the difference of working fluid on thermal efficiency were carried out. Next, as the cycle approximately realizing isothermal compression process with condensation process, the super-critical pressure cycle with liquid phase compression was rated, and four working fluids, NH 3 , SO 2 , CO 2 and H 2 O were examined as perfect gas and real gas. The advantage of CO 2 regeneration for the thermal efficiency improvement was clarified by using the dimensionless characteristic number. The graphical presentation of effective work, the thermal efficiency improvement by regeneration, the thermal efficiency improvement by making compression process isothermal, the effect on thermal efficiency due to various factors and working fluids, the characteristic number by regeneration, and the application to real working fluids are reported. (Kako, I.)

  16. Efficiency improvement of flexible fluorescent and phosphorescent organic light emitting diodes by inserting a spin-coating buffer layer

    International Nuclear Information System (INIS)

    Tsai, Yu-Sheng; Wang, Shun-Hsi; Chen, Shen-Yaur; Su, Shin-Yuan; Juang, Fuh-Shyang

    2009-01-01

    We dissolved hole transport materials α-NPD and NPB in THF solvent, and spin-coated the α-NPD + THF or NPB + THF solution onto ITO anode surface to improve the luminance efficiency and lifetime of flexible fluorescent and phosphorescent organic light emitting diodes. Then the BCP and TPBi were employed as hole blocking layer (HBL) of phosphorescent device and its thickness was optimized. From the experimental results, the maximum luminance efficiency is 4.4 cd/A at 9 V of fluorescent device and 24.4 cd/A of phosphorescent device, respectively. Such an improvement in the device performance was attributed to the smoother surface and good contact between the interface of spin-coated HTL/ITO, the hole were effectively injected from the anode into the organic layer. And the deposited HTL can block excitons from diffusing into the anode to quench, thus improving the luminance efficiency and lifetime greatly.

  17. Incentives to improve energy efficiency in EU Grids

    Energy Technology Data Exchange (ETDEWEB)

    Papaefthymiou, G.; Beestermoeller, C.; Gardiner, A.

    2013-04-15

    The Energy Efficiency Directive (2012/27/EU) includes provisions related to network tariffs and regulation. It is timely therefore to revisit the potential options for energy efficiency in grids, the treatment of energy efficiency in network tariffs and alternative policies for improving energy efficiency. This project builds on work done previously for the European Copper Institute in this area. In this paper, we concentrate on energy efficiency in electricity network design and operation. Other articles in the Directive relate to the role of the network tariffs and regulations in enabling or incentivising the provision of energy efficiency to end users. In section 2, we describe technical efficiency measures to reduce losses (improve energy efficiency) in the grid. Section 3 reviews grid tariffs in three countries to identify whether they provide incentives or disincentives for energy efficiency in the grid. Section 4 discusses and evaluates alternative regulations for energy efficiency in grids. Section 5 concludes and discusses the main components of the optimal policy framework.

  18. Efficient fluorescent deep-blue and hybrid white emitting devices based on carbazole/benzimidazole compound

    KAUST Repository

    Yang, Xiaohui

    2011-07-28

    We report the synthesis, photophysics, and electrochemical characterization of carbazole/benzimidazole-based compound (Cz-2pbb) and efficient fluorescent deep-blue light emitting devices based on Cz-2pbb with the peak external quantum efficiency of 4.1% and Commission Internationale dÉnclairage coordinates of (0.16, 0.05). Efficient deep-blue emission as well as high triplet state energy of Cz-2pbb enables fabrication of hybrid white organic light emitting diodes with a single emissive layer. Hybrid white emitting devices based on Cz-2pbb show the peak external quantum efficiency exceeding 10% and power efficiency of 14.8 lm/W at a luminance of 500 cd/m2. © 2011 American Chemical Society.

  19. Single-crystal charge transfer interfaces for efficient photonic devices (Conference Presentation)

    Science.gov (United States)

    Alves, Helena; Pinto, Rui M.; Maçôas, Ermelinda M. S.; Baleizão, Carlos; Santos, Isabel C.

    2016-09-01

    Organic semiconductors have unique optical, mechanical and electronic properties that can be combined with customized chemical functionality. In the crystalline form, determinant features for electronic applications such as molecular purity, the charge mobility or the exciton diffusion length, reveal a superior performance when compared with materials in a more disordered form. Combining crystals of two different conjugated materials as even enable a new 2D electronic system. However, the use of organic single crystals in devices is still limited to a few applications, such as field-effect transistors. In 2013, we presented the first system composed of single-crystal charge transfer interfaces presenting photoconductivity behaviour. The system composed of rubrene and TCNQ has a responsivity reaching 1 A/W, corresponding to an external quantum efficiency of nearly 100%. A similar approach, with a hybrid structure of a PCBM film and rubrene single crystal also presents high responsivity and the possibility to extract excitons generated in acceptor materials. This strategy led to an extended action towards the near IR. By adequate material design and structural organisation of perylediimides, we demonstrate that is possible to improve exciton diffusion efficiency. More recently, we have successfully used the concept of charge transfer interfaces in phototransistors. These results open the possibility of using organic single-crystal interfaces in photonic applications.

  20. Improved Feature Matching for Mobile Devices with IMU

    Directory of Open Access Journals (Sweden)

    Andrea Masiero

    2016-08-01

    Full Text Available Thanks to the recent diffusion of low-cost high-resolution digital cameras and to the development of mostly automated procedures for image-based 3D reconstruction, the popularity of photogrammetry for environment surveys is constantly increasing in the last years. Automatic feature matching is an important step in order to successfully complete the photogrammetric 3D reconstruction: this step is the fundamental basis for the subsequent estimation of the geometry of the scene. This paper reconsiders the feature matching problem when dealing with smart mobile devices (e.g., when using the standard camera embedded in a smartphone as imaging sensor. More specifically, this paper aims at exploiting the information on camera movements provided by the inertial navigation system (INS in order to make the feature matching step more robust and, possibly, computationally more efficient. First, a revised version of the affine scale-invariant feature transform (ASIFT is considered: this version reduces the computational complexity of the original ASIFT, while still ensuring an increase of correct feature matches with respect to the SIFT. Furthermore, a new two-step procedure for the estimation of the essential matrix E (and the camera pose is proposed in order to increase its estimation robustness and computational efficiency.

  1. Low Impedance Voice Coils for Improved Loudspeaker Efficiency

    DEFF Research Database (Denmark)

    Iversen, Niels Elkjær; Knott, Arnold; Andersen, Michael A. E.

    2015-01-01

    In modern audio systems utilizing switch-mode amplifiers the total efficiency is dominated by the rather poor efficiency of the loudspeaker. For decades voice coils have been designed so that nominal resistances of 4 to 8 Ohms is obtained, despite modern audio amplifiers, using switch-mode techno...... responses are estimated. For this woofer it is shown that the sensitivity can be improved approximately 1 dB, corresponding to a 30% efficiency improvement, just by increasing the fill factor using a low impedance voice coil with rectangular wire....

  2. A high-efficiency solution-deposited thin-film photovoltaic device

    Energy Technology Data Exchange (ETDEWEB)

    Mitzi, David B; Yuan, Min; Liu, Wei; Chey, S Jay; Schrott, Alex G [IBM T. J. Watson Research Center, Yorktown Heights, NY (United States); Kellock, Andrew J; Deline, Vaughn [IBM Almaden Research Center, San Jose, CA (United States)

    2008-10-02

    High-quality Cu(In,Ga)Se{sub 2} (CIGS) films are deposited from hydrazine-based solutions and are employed as absorber layers in thin-film photovoltaic devices. The CIGS films exhibit tunable stoichiometry and well-formed grain structure without requiring post-deposition high-temperature selenium treatment. Devices based on these films offer power conversion efficiencies of 10% (AM1.5 illumination). (Abstract Copyright [2008], Wiley Periodicals, Inc.)

  3. DTU International Energy Report 2012: Energy efficiency improvements

    DEFF Research Database (Denmark)

    Increased energy efficiency can reduce global CO2 emissions over the period to 2050 with up to 25%. On the top of that large profits can be gained for very little investment. Energy efficiency improvements can save investment in new energy infrastructure, cut fuel costs, increase competitiveness...... and increase consumer welfare. Thus, it is natural for DTU International Energy Report 2012 to take up this issue and analyze the global, regional and national challenges in exploiting energy efficiency and promote research and development in energy efficiency....

  4. Method for calculating annual energy efficiency improvement of TV sets

    International Nuclear Information System (INIS)

    Varman, M.; Mahlia, T.M.I.; Masjuki, H.H.

    2006-01-01

    The popularization of 24 h pay-TV, interactive video games, web-TV, VCD and DVD are poised to have a large impact on overall TV electricity consumption in the Malaysia. Following this increased consumption, energy efficiency standard present a highly effective measure for decreasing electricity consumption in the residential sector. The main problem in setting energy efficiency standard is identifying annual efficiency improvement, due to the lack of time series statistical data available in developing countries. This study attempts to present a method of calculating annual energy efficiency improvement for TV set, which can be used for implementing energy efficiency standard for TV sets in Malaysia and other developing countries. Although the presented result is only an approximation, definitely it is one of the ways of accomplishing energy standard. Furthermore, the method can be used for other appliances without any major modification

  5. Method for calculating annual energy efficiency improvement of TV sets

    Energy Technology Data Exchange (ETDEWEB)

    Varman, M. [Department of Mechanical Engineering, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia); Mahlia, T.M.I. [Department of Mechanical Engineering, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia)]. E-mail: indra@um.edu.my; Masjuki, H.H. [Department of Mechanical Engineering, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur (Malaysia)

    2006-10-15

    The popularization of 24 h pay-TV, interactive video games, web-TV, VCD and DVD are poised to have a large impact on overall TV electricity consumption in the Malaysia. Following this increased consumption, energy efficiency standard present a highly effective measure for decreasing electricity consumption in the residential sector. The main problem in setting energy efficiency standard is identifying annual efficiency improvement, due to the lack of time series statistical data available in developing countries. This study attempts to present a method of calculating annual energy efficiency improvement for TV set, which can be used for implementing energy efficiency standard for TV sets in Malaysia and other developing countries. Although the presented result is only an approximation, definitely it is one of the ways of accomplishing energy standard. Furthermore, the method can be used for other appliances without any major modification.

  6. Costs and benefits of energy efficiency improvements in ceiling fans

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Nihar; Sathaye, Nakul; Phadke, Amol; Letschert, Virginie [Lawrence Berkeley National Lab., CA (United States). Environmental Energy Technology Division

    2013-10-15

    Ceiling fans contribute significantly to residential electricity consumption, especially in developing countries with warm climates. The paper provides analysis of costs and benefits of several options to improve the efficiency of ceiling fans to assess the global potential for electricity savings and green house gas (GHG) emission reductions. Ceiling fan efficiency can be cost-effectively improved by at least 50% using commercially available technology. If these efficiency improvements are implemented in all ceiling fans sold by 2020, 70 terawatt hours per year could be saved and 25 million metric tons of carbon dioxide equivalent (CO2-e) emissions per year could be avoided, globally. We assess how policies and programs such as standards, labels, and financial incentives can be used to accelerate the adoption of efficient ceiling fans in order to realize potential savings.

  7. Improved Efficient Routing Strategy on Scale-Free Networks

    Science.gov (United States)

    Jiang, Zhong-Yuan; Liang, Man-Gui

    Since the betweenness of nodes in complex networks can theoretically represent the traffic load of nodes under the currently used routing strategy, we propose an improved efficient (IE) routing strategy to enhance to the network traffic capacity based on the betweenness centrality. Any node with the highest betweenness is susceptible to traffic congestion. An efficient way to improve the network traffic capacity is to redistribute the heavy traffic load from these central nodes to non-central nodes, so in this paper, we firstly give a path cost function by considering the sum of node betweenness with a tunable parameter β along the actual path. Then, by minimizing the path cost, our IE routing strategy achieved obvious improvement on the network transport efficiency. Simulations on scale-free Barabási-Albert (BA) networks confirmed the effectiveness of our strategy, when compared with the efficient routing (ER) and the shortest path (SP) routing.

  8. Improving risk assessment of color additives in medical device polymers.

    Science.gov (United States)

    Chandrasekar, Vaishnavi; Janes, Dustin W; Forrey, Christopher; Saylor, David M; Bajaj, Akhil; Duncan, Timothy V; Zheng, Jiwen; Riaz Ahmed, Kausar B; Casey, Brendan J

    2018-01-01

    Many polymeric medical device materials contain color additives which could lead to adverse health effects. The potential health risk of color additives may be assessed by comparing the amount of color additive released over time to levels deemed to be safe based on available toxicity data. We propose a conservative model for exposure that requires only the diffusion coefficient of the additive in the polymer matrix, D, to be specified. The model is applied here using a model polymer (poly(ether-block-amide), PEBAX 2533) and color additive (quinizarin blue) system. Sorption experiments performed in an aqueous dispersion of quinizarin blue (QB) into neat PEBAX yielded a diffusivity D = 4.8 × 10 -10 cm 2  s -1 , and solubility S = 0.32 wt %. On the basis of these measurements, we validated the model by comparing predictions to the leaching profile of QB from a PEBAX matrix into physiologically representative media. Toxicity data are not available to estimate a safe level of exposure to QB, as a result, we used a Threshold of Toxicological Concern (TTC) value for QB of 90 µg/adult/day. Because only 30% of the QB is released in the first day of leaching for our film thickness and calculated D, we demonstrate that a device may contain significantly more color additive than the TTC value without giving rise to a toxicological concern. The findings suggest that an initial screening-level risk assessment of color additives and other potentially toxic compounds found in device polymers can be improved. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 310-319, 2018. © 2017 Wiley Periodicals, Inc.

  9. High-power waveguide resonator second harmonic device with external conversion efficiency up to 75%

    Science.gov (United States)

    Stefszky, M.; Ricken, R.; Eigner, C.; Quiring, V.; Herrmann, H.; Silberhorn, C.

    2018-06-01

    We report on a highly efficient waveguide resonator device for the production of 775 nm light using a titanium indiffused LiNbO3 waveguide resonator. When scanning the resonance, the device produces up to 110 mW of second harmonic power with 140 mW incident on the device—an external conversion efficiency of 75%. The cavity length is also locked, using a Pound–Drever–Hall type locking scheme, involving feedback to either the cavity temperature or the laser frequency. With laser frequency feedback, a stable output power of approximately 28 mW from a 52 mW pump is seen over one hour.

  10. Investigation of Unequal Planar Wireless Electricity Device for Efficient Wireless Power Transfer

    Directory of Open Access Journals (Sweden)

    M. H. Mohd Salleh

    2017-04-01

    Full Text Available This article focuses on the design and investigation of a pair of unequally sized wireless electricity (Witricity devices that are equipped with integrated planar coil strips. The proposed pair of devices consists of two different square-shaped resonator sizes of 120 mm × 120 mm and 80 mm × 80 mm, acting as a transmitter and receiver, respectively. The devices are designed, simulated and optimized using the CST Microwave Studio software prior to being fabricated and verified using a vector network analyzer (VNA. The surface current results of the coupled devices indicate a good current density at 10 mm to 30 mm distance range. This good current density demonstrates that the coupled devices’ surface has more electric current per unit area, which leads to a good performance up to 30 mm range. Hence, the results also reveal good coupling efficiency between the coupled devices, which is approximately 54.5% at up to a 30 mm distance, with both devices axially aligned. In addition, a coupling efficiency of 50% is achieved when a maximum lateral misalignment (LM of 10 mm, and a varied angular misalignment (AM from 0° to 40° are implemented to the proposed device.

  11. Quality and Efficiency Improvement Tools for Every Radiologist.

    Science.gov (United States)

    Kudla, Alexei U; Brook, Olga R

    2018-03-20

    In an era of value-based medicine, data-driven quality improvement is more important than ever to ensure safe and efficient imaging services. Familiarity with high-value tools enables all radiologists to successfully engage in quality and efficiency improvement. In this article, we review the model for improvement, strategies for measurement, and common practical tools with real-life examples that include Run chart, Control chart (Shewhart chart), Fishbone (Cause-and-Effect or Ishikawa) diagram, Pareto chart, 5 Whys, and Root Cause Analysis. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  12. Barriers to efficiency improvement and fuel switching in Karnataka, India

    International Nuclear Information System (INIS)

    Reddy, A.

    1991-01-01

    Implementing energy efficiency changes requires a wide range measures. Improvements, therefore, require actions at the lowest level of the consumer, through the highest level of the global agencies. Due to the multiplicity of participants, however, barriers to achieving these improvements can arise at every level. The major barriers to improving energy efficiency in developing countries are defined and paths to overcome these challenges are identified. Topics of discussion include: energy consumers; end-use equipment manufacturers; end-use equipment providers; energy carrier producers and distributors; actual/potential cogenerators; financial institutions; government; and international, multilateral and industrialized country funding/aid agencies

  13. Water quality improving device of nuclear power plant

    International Nuclear Information System (INIS)

    Mori, Tsuguo.

    1994-01-01

    In the device of the present invention, the amount of an oxygen injected to an inlet of a recombiner is automatically controlled by detecting an oxygen concentration at the exit of the recombiner. Accordingly, the range for the concentration of dissolved oxygen at the exit of the recombiner is appropriately maintained. That is, the device of the present invention comprises a hydrogen injection means, hydrogen concentration measuring means, oxygen injection means, oxygen concentration measuring means and control means. If a hydrogen gas is injected to condensates which are to be coolants of the reactor, it is combined with the dissolved oxygen in the coolants. Excessive hydrogen in this case is measured by an off-gas system, and oxygen of an amount corresponding to the amount for combining the excessive hydrogen is injected to the inlet of the recombiner. The oxygen concentration at the exit of the recombiner is measured. If the result of the measurement is out of a predetermined range, the injection amount of oxygen is increased or decreased to conduct automatic control so that oxygen is within a predetermined range. As a result, the improvement for the water quality of the reactor coolants and processing of the excessive hydrogen gas can be conducted smoothly, stably and safely. (I.S.)

  14. Ultrathin high band gap solar cells with improved efficiencies from the world's oldest photovoltaic material.

    Science.gov (United States)

    Todorov, Teodor K; Singh, Saurabh; Bishop, Douglas M; Gunawan, Oki; Lee, Yun Seog; Gershon, Talia S; Brew, Kevin W; Antunez, Priscilla D; Haight, Richard

    2017-09-25

    Selenium was used in the first solid state solar cell in 1883 and gave early insights into the photoelectric effect that inspired Einstein's Nobel Prize work; however, the latest efficiency milestone of 5.0% was more than 30 years ago. The recent surge of interest towards high-band gap absorbers for tandem applications led us to reconsider this attractive 1.95 eV material. Here, we show completely redesigned selenium devices with improved back and front interfaces optimized through combinatorial studies and demonstrate record open-circuit voltage (V OC ) of 970 mV and efficiency of 6.5% under 1 Sun. In addition, Se devices are air-stable, non-toxic, and extremely simple to fabricate. The absorber layer is only 100 nm thick, and can be processed at 200 ˚C, allowing temperature compatibility with most bottom substrates or sub-cells. We analyze device limitations and find significant potential for further improvement making selenium an attractive high-band-gap absorber for multi-junction device applications.Wide band gap semiconductors are important for the development of tandem photovoltaics. By introducing buffer layers at the front and rear side of solar cells based on selenium; Todorov et al., reduce interface recombination losses to achieve photoconversion efficiencies of 6.5%.

  15. Improved luminescence properties of nanocrystalline silicon based electroluminescent device by annealing

    International Nuclear Information System (INIS)

    Sato, Keisuke; Hirakuri, Kenji

    2006-01-01

    We report an annealing effect on electrical and luminescence properties of a red electroluminescent device consisting of nanocrystalline silicon (nc-Si). The red luminescence was generated by flowing the forward current into the device at a low threshold direct current (DC) forward voltage with a rise of annealing temperature up to 500 deg. C. Moreover, the luminescence of the device annealed at 500 deg. C was more intense than that of the device annealed at 200 deg. C or less under the same forward current density, because of the injection of a large quantity of carriers to the radiative recombination centers at the nc-Si surface vicinity. These were attained by a low resistivity of indium tin oxide (ITO) electrode and good contact at the ITO electrode/luminous layer interface region by the annealing treatment. The above results indicated that the annealing treatment of the device is effective for the realization of high luminance due to the improvement in the injection efficiency of carriers to the radiative recombination centers

  16. Efficiency improvement opportunities in TVs: Implications for market transformation programs

    International Nuclear Information System (INIS)

    Park, Won Young; Phadke, Amol; Shah, Nihar; Letschert, Virginie

    2013-01-01

    Televisions (TVs) account for a significant portion of residential electricity consumption and global TV shipments are expected to continue to increase. We assess the market trends in the energy efficiency of TVs that are likely to occur without any additional policy intervention and estimate that TV efficiency will likely improve by over 60% by 2015 with savings potential of 45 terawatt-hours [TW h] per year in 2015, compared to today’s technology. We discuss various energy-efficiency improvement options and evaluate the cost effectiveness of three of them. At least one of these options improves efficiency by at least 20% cost effectively beyond ongoing market trends. We provide insights for policies and programs that can be used to accelerate the adoption of efficient technologies to further capture global energy savings potential from TVs which we estimate to be up to 23 TW h per year in 2015. - Highlights: • We analyze the impact of the recent TV market transition on TV energy consumption. • We review TV technology options that could be realized in the near future. • We assess the cost-effectiveness of selected energy-efficiency improvement options. • We estimate global electricity savings potential in selected scenarios. • We discuss possible directions of market transformation programs

  17. Method of improving the decontaminating efficiency of ruthenium in evaporating treatment of nitric acid

    International Nuclear Information System (INIS)

    Kubota, Kanya; Yamana, Hajime; Takeda, Seiichiro.

    1984-01-01

    Purpose: To significantly improve the ruthenium removing efficiency in a nitric acid solution in an acid recovery system for the recovery of nitric acid from nitric acid liquid wastes through evaporating condensation. Method: Upon evaporating treatment of nitric acid solution containing ruthenium by supplying and heating the solution to a nitric acid evaporating device, hydrazine is previously added to the nitric acid solution. Hydrazine and intermediate reaction product of hydrazine such as azide causes a reduction reaction with intermediate reaction product of ruthenium tetraoxide to suppress the oxidation of ruthenium and thereby improve the decontaminating efficiency of ruthenium. The amount of hydrazine to be added is preferably between 20 - 500 mg/l and most suitably between 200 - 2000 mg/l per one liter of the liquid in the evaporating device. (Seki, T.)

  18. Spreading The Net: The Multiple Benefits Of Energy Efficiency Improvements

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    Improving energy efficiency can deliver a range of benefits to the economy and society. However energy efficiency programmes are often evaluated only on the basis of the energy savings they deliver. As a result, the full value of energy efficiency improvements in both national and global economies may be significantly underestimated. This also means that energy efficiency policy may not be optimised to target the potential of the full range of outcomes possible. Moreover, when the merit of energy efficiency programmes is judged solely on reductions in energy demand, programmes are susceptible to criticisms related to the rebound effect when the energy savings are less than expected due to other welfare gains. There are several reasons why the full range of outcomes from energy efficiency policy is not generally evaluated. First, it is due to the non-market, somewhat intangible, nature of the socioeconomic benefits, which makes them difficult to quantify. Second, the effects due to energy efficiency alone can be complex to isolate and to determine causality. Third, evaluators and policy makers working in the energy efficiency sphere are usually energy professionals, working for an energy agency or ministry, with little experience of how energy efficiency might impact other non-energy sectors. The result is an under-appreciation – and related underinvestment – in energy efficiency, and as a consequence, missed opportunities and benefits. These foregone benefits represent the ‘opportunity cost’ of failing to adequately evaluate and prioritize energy efficiency investments. The objective of this report is to fully outline the array of different benefits from improved energy efficiency and investigate their implications for policy design. By better understanding the different benefits arising from energy efficiency it should be easier for policy makers to prioritise the most significant outcomes, in addition to energy savings, in optimising energy efficiency

  19. Recovery Act--Class 8 Truck Freight Efficiency Improvement Project

    Energy Technology Data Exchange (ETDEWEB)

    Trucks, Daimler [Daimler Trucks North America Llc, Portland, OR (United States)

    2015-07-26

    Daimler Trucks North America completed a five year, $79.6M project to develop and demonstrate a concept vehicle with at least 50% freight efficiency improvement over a weighted average of several drive cycles relative to a 2009 best-in-class baseline vehicle. DTNA chose a very fuel efficient baseline vehicle, the 2009 Freightliner Cascadia with a DD15 engine, yet successfully demonstrated a 115% freight efficiency improvement. DTNA learned a great deal about the various technologies that were incorporated into Super Truck and those that, through down-selection, were discarded. Some of the technologies competed with each other for efficiency, and notably some of the technologies complemented each other. For example, we found that Super Truck’s improved aerodynamic drag resulted in improved fuel savings from eCoast, relative to a similar vehicle with worse aerodynamic drag. However, some technologies were in direct competition with each other, namely the predictive technologies which use GPS and 3D digital maps to efficiently manage the vehicles kinetic energy through controls and software, versus hybrid which is a much costlier technology that essentially targets the same inefficiency. Furthermore, the benefits of a comprehensive, integrated powertrain/vehicle approach was proven, in which vast improvements in vehicle efficiency (e.g. lower aero drag and driveline losses) enabled engine strategies such as downrating and downspeeding. The joint engine and vehicle developments proved to be a multiplier-effect which resulted in large freight efficiency improvements. Although a large number of technologies made the selection process and were used on the Super Truck demonstrator vehicle, some of the technologies proved not feasible for series production.

  20. Potentials and policy implications of energy and material efficiency improvement

    Energy Technology Data Exchange (ETDEWEB)

    Worrell, Ernst; Levine, Mark; Price, Lynn; Martin, Nathan; van den Broek, Richard; Block, Kornelis

    1997-01-01

    There is a growing awareness of the serious problems associated with the provision of sufficient energy to meet human needs and to fuel economic growth world-wide. This has pointed to the need for energy and material efficiency, which would reduce air, water and thermal pollution, as well as waste production. Increasing energy and material efficiency also have the benefits of increased employment, improved balance of imports and exports, increased security of energy supply, and adopting environmentally advantageous energy supply. A large potential exists for energy savings through energy and material efficiency improvements. Technologies are not now, nor will they be, in the foreseeable future, the limiting factors with regard to continuing energy efficiency improvements. There are serious barriers to energy efficiency improvement, including unwillingness to invest, lack of available and accessible information, economic disincentives and organizational barriers. A wide range of policy instruments, as well as innovative approaches have been tried in some countries in order to achieve the desired energy efficiency approaches. These include: regulation and guidelines; economic instruments and incentives; voluntary agreements and actions, information, education and training; and research, development and demonstration. An area that requires particular attention is that of improved international co-operation to develop policy instruments and technologies to meet the needs of developing countries. Material efficiency has not received the attention that it deserves. Consequently, there is a dearth of data on the qualities and quantities for final consumption, thus, making it difficult to formulate policies. Available data, however, suggest that there is a large potential for improved use of many materials in industrialized countries.

  1. Efficient blue-green and green electroluminescent devices obtained by doping iridium complexes into hole-block material as supplementary light-emitting layer

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Liang [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Zheng, Youxuan, E-mail: yxzheng@mail.nju.edu.cn [State Key Laboratory of Coordination Chemistry, Nanjing National Laboratory of Microstructures, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (China); Deng, Ruiping; Feng, Jing; Song, Mingxing; Hao, Zhaomin [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Zhang, Hongjie, E-mail: hongjie@ciac.jl.cn [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Zuo, Jinglin; You, Xiaozeng [State Key Laboratory of Coordination Chemistry, Nanjing National Laboratory of Microstructures, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (China)

    2014-04-15

    In this work, organic electroluminescent (EL) devices with dominant and supplementary light-emitting layers (EMLs) were designed to further improve the EL performances of two iridium{sup III}-based phosphorescent complexes, which have been reported to provide EL devices with slow EL efficiency roll-off. The widely used hole-block material 2,2′,2''-(1,3,5-Benzinetriyl)-tris(1-phenyl-1-H-benzimidazole) (TPBi) was selected as host material to construct the supplementary EML. Compared with single-EML devices, double-EMLs devices showed higher EL efficiencies, higher brightness, and lower operation voltage attributed to wider recombination zone and better balance of carriers. In addition, the insertion of supplementary EML is instrumental in facilitating carriers trapping, thus improving the color purity. Finally, high performance blue-green and green EL devices with maximum current efficiencies of 35.22 and 90.68 cd/A, maximum power efficiencies of 26.36 and 98.18 lm/W, and maximum brightness of 56,678 and 112,352 cd/m{sup 2}, respectively, were obtained by optimizing the doping concentrations. Such a device design strategy extends the application of a double EML device structure and provides a chance to simplify device fabrication processes. -- Highlights: • Electroluminescent devices with supplementary light-emitting layer were fabricated. • Doping concentrations and thicknesses were optimized. • Better balance of holes and electrons causes the enhanced efficiency. • Improved carrier trapping suppresses the emission of host material.

  2. Efficiency improvement for vehicle powertrains using energy integration techniques

    OpenAIRE

    Dimitrova, Zlatina; Maréchal, François

    2016-01-01

    The main design criteria for the modern sustainable development of vehicle powertrains are the high energy efficiency of the conversion system, the competitive cost and the lowest possible environmental impacts. The need for efficiency improvement of the vehicle energy system induces the search for an innovative methodology during the design process. In this article the energy services for mobility and comfort are integrated. The energy integration of the mobility and the comfort service is a...

  3. Upgrading and efficiency improvement in coal-fired power plants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-08-01

    Improving the efficiencies of the large number of older coal-fired power plants operating around the world would give major savings in CO2 emissions together with significant other benefits. This report begins with a summary of the ways efficiency can become degraded and of the means available to combat the decrease in performance. These include improvements to operating and maintenance practices and more major techniques that are available, including boiler and turbine retrofits. There is also an update on fuel drying developments as a route to higher efficiency in plants firing high moisture lignites. The largest chapter of the report contains a number of descriptions of case study improvement projects, to illustrate measures that have been applied, benefits that have been achieved and identify best practices, which are summarised. Major national and international upgrading programmes are described.

  4. Compact and high-efficiency device for Raman scattering measurement using optical fibers.

    Science.gov (United States)

    Mitsui, Tadashi

    2014-11-01

    We describe the design and development of a high-efficiency optical measurement device for operation within the small bore of a high-power magnet at low temperature. For the high-efficiency measurement of light emitted from this small region, we designed a compact confocal optics with lens focusing and tilting systems, and used a piezodriven translation stage that allows micron-scale focus control of the sample position. We designed a measurement device that uses 10 m-long optical fibers in order to avoid the influence of mechanical vibration and magnetic field leakage of high-power magnets, and we also describe a technique for minimizing the fluorescence signal of optical fibers. The operation of the device was confirmed by Raman scattering measurements of monolayer graphene on quartz glass with a high signal-to-noise ratio.

  5. Electric motor systems in developing countries: Opportunities for efficiency improvement

    Energy Technology Data Exchange (ETDEWEB)

    Meyers, S.; Monahan, P.; Lewis, P.; Greenberg, S. [Lawrence Berkeley Lab., CA (United States); Nadel, S. [American Council for an Energy-Efficient Economy, Washington, DC (United States)

    1993-08-01

    This report presents an overview of the current status and efficiency improvement potential of industrial motor systems in developing countries. Better management of electric motor systems is of particular relevance in developing countries, where improved efficiency can lead to increased productivity and slower growth in electricity demand. Motor systems currently consume some 65--80% of the industrial electricity in developing countries. Drawing on studies from Thailand, India, Brazil, China, Pakistan, and Costa Rica, we describe potential efficiency gains in various parts of the motor system, from the electricity delivery system through the motor to the point where useful work is performed. We report evidence of a significant electricity conservation potential. Most of the efficiency improvement methods we examine are very cost-effective from a societal viewpoint, but are generally not implemented due to various barriers that deter their adoption. Drawing on experiences in North America, we discuss a range of policies to overcome these barriers, including education, training, minimum efficiency standards, motor efficiency testing protocols, technical assistance programs, and financial incentives.

  6. TV Energy Consumption Trends and Energy-Efficiency Improvement Options

    Energy Technology Data Exchange (ETDEWEB)

    Park, Won Young; Phadke, Amol; Shah, Nihar; Letschert, Virginie

    2011-07-01

    The SEAD initiative aims to transform the global market by increasing the penetration of highly efficient equipment and appliances. SEAD is a government initiative whose activities and projects engage the private sector to realize the large global energy savings potential from improved appliance and equipment efficiency. SEAD seeks to enable high-level global action by informing the Clean Energy Ministerial dialogue as one of the initiatives in the Global Energy Efficiency Challenge. In keeping with its goal of achieving global energy savings through efficiency, SEAD was approved as a task within the International Partnership for Energy Efficiency Cooperation (IPEEC) in January 2010. SEAD partners work together in voluntary activities to: (1) ?raise the efficiency ceiling? by pulling super-efficient appliances and equipment into the market through cooperation on measures like incentives, procurement, awards, and research and development (R&D) investments; (2) ?raise the efficiency floor? by working together to bolster national or regional policies like minimum efficiency standards; and (3) ?strengthen the efficiency foundations? of programs by coordinating technical work to support these activities. Although not all SEAD partners may decide to participate in every SEAD activity, SEAD partners have agreed to engage actively in their particular areas of interest through commitment of financing, staff, consultant experts, and other resources. In addition, all SEAD partners are committed to share information, e.g., on implementation schedules for and the technical detail of minimum efficiency standards and other efficiency programs. Information collected and created through SEAD activities will be shared among all SEAD partners and, to the extent appropriate, with the global public.As of April 2011, the governments participating in SEAD are: Australia, Brazil, Canada, the European Commission, France, Germany, India, Japan, Korea, Mexico, Russia, South Africa, Sweden

  7. Efficient Generation and Selection of Combined Features for Improved Classification

    KAUST Repository

    Shono, Ahmad N.

    2014-05-01

    This study contributes a methodology and associated toolkit developed to allow users to experiment with the use of combined features in classification problems. Methods are provided for efficiently generating combined features from an original feature set, for efficiently selecting the most discriminating of these generated combined features, and for efficiently performing a preliminary comparison of the classification results when using the original features exclusively against the results when using the selected combined features. The potential benefit of considering combined features in classification problems is demonstrated by applying the developed methodology and toolkit to three sample data sets where the discovery of combined features containing new discriminating information led to improved classification results.

  8. Design principle for efficient charge separation at the donor-acceptor interface for high performance organic solar cell device

    Science.gov (United States)

    Nie, Wanyi; Gupta, Gautam; Crone, Brian; Wang, Hsing-Lin; Mohite, Aditya; MPA-11 Material synthesis and integrated device Team; MPA-chemistry Team

    2014-03-01

    The performance of donor (D) /acceptor (A) structure based organic electronic devices, such as solar cell, light emitting devices etc., relays on the charge transfer process at the interface dramatically. In organic solar cell, the photo-induced electron-hole pair is tightly bonded and will form a charge transfer (CT) state at the D/A interface after dissociation. There is a large chance for them to recombine through CT state and thus is a major loss that limit the overall performance. Here, we report three different strategies that allow us to completely suppress the exciplex (or charge transfer state) recombination between any D/A system. We observe that the photocurrent increases by 300% and the power conversion efficiency increases by 4-5 times simply by inserting a spacer layer in the form of an a) insulator b) Oliogomer or using a c) heavy atom at the donor-acceptor interface in a P3HT/C60 bilayer device. By using those different functional mono layers, we successfully suppressed the exciplex recombination in evidence of increased photocurrent and open circuit voltage. Moreover, these strategies are applicable universally to any donor-acceptor interface. And we demonstrated such strategies in a bulk-heterojunction device which improved the power conversion efficiency from 3.5% up to 4.6%.

  9. Improving Software Performance in the Compute Unified Device Architecture

    Directory of Open Access Journals (Sweden)

    Alexandru PIRJAN

    2010-01-01

    Full Text Available This paper analyzes several aspects regarding the improvement of software performance for applications written in the Compute Unified Device Architecture CUDA. We address an issue of great importance when programming a CUDA application: the Graphics Processing Unit’s (GPU’s memory management through ranspose ernels. We also benchmark and evaluate the performance for progressively optimizing a transposing matrix application in CUDA. One particular interest was to research how well the optimization techniques, applied to software application written in CUDA, scale to the latest generation of general-purpose graphic processors units (GPGPU, like the Fermi architecture implemented in the GTX480 and the previous architecture implemented in GTX280. Lately, there has been a lot of interest in the literature for this type of optimization analysis, but none of the works so far (to our best knowledge tried to validate if the optimizations can apply to a GPU from the latest Fermi architecture and how well does the Fermi architecture scale to these software performance improving techniques.

  10. Improving yield of PZT piezoelectric devices on glass substrates

    Science.gov (United States)

    Johnson-Wilke, Raegan L.; Wilke, Rudeger H. T.; Cotroneo, Vincenzo; Davis, William N.; Reid, Paul B.; Schwartz, Daniel A.; Trolier-McKinstry, Susan

    2012-10-01

    The proposed SMART-X telescope includes adaptive optics systems that use piezoelectric lead zirconate titanate (PZT) films deposited on flexible glass substrates. Several processing constraints are imposed by current designs: the crystallization temperature must be kept below 550 °C, the total stress in the film must be minimized, and the yield on 1 cm2 actuator elements should be work, RF magnetron sputtering was used to deposit films since chemical solution deposition (CSD) led to warping of large area flexible glass substrates. A PZT 52/48 film that wasdeposited at 4 mTorr and annealed at 550 °C for 24 hours showed no detectable levels of either PbO or pyrochlore second phases. Large area electrodes (1cm x 1 cm) were deposited on 4" glass substrates. Initially, the yield of the devices was low, however, two methods were employed to increase the yield to near 100 %. The first method included a more rigorous cleaning to improve the continuity of the Pt bottom electrode. The second method was to apply 3 V DC across the capacitor structure to burn out regions of defective PZT. The result of this latter method essentially removed conducting filaments in the PZT but left the bulk of the material undamaged. By combining these two methods, the yield on the large area electrodes improved from < 10% to nearly 100%.

  11. SAGD CO2 mitigation through energy efficiency improvements

    International Nuclear Information System (INIS)

    Plessis du, D.

    2010-01-01

    An evaluation of the carbon dioxide (CO 2 ) emissions reductions achieved using energy efficiency measures in steam assisted gravity drainage (SAGD) operations was presented. The efficiency of a typical SAGD operation was analyzed using an indexing tool based on the Carnot cycle efficiency to develop an ideal SAGD heat cycle. The benefits of using an organic Rankine cycle (ORC) technology to convert waste heat to electrical power were also investigated. A CO 2 abatement curve was used to identify the economic benefits and costs of various greenhouse gas (GHG) reductions. The level of recovered energy was determined in relation to energy prices, capital costs, and carbon penalties in order to determine the most efficient means of decreasing energy usage. The study demonstrated that energy efficiency can be improved by up to 20 percent, and water loss reductions of up to 50 percent can be achieved using cost-effective energy efficiency measures. Results of the study can be used to guide government policy and provide industry with practical tools to benchmark performance and improve efficiencies. 4 refs., 1 tab., 10 figs.

  12. Potential Global Benefits of Improved Ceiling Fan Energy Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Sathaye, Nakul [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Phadke, Amol [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Shah, Nihar [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Letschert, Virginie [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-10-31

    Ceiling fans contribute significantly to residential electricity consumption, both in an absolute sense and as a proportion of household consumption in many locations, especially in developing countries in warm climates. However, there has been little detailed assessment of the costs and benefits of efficiency improvement options for ceiling fans and the potential resulting electricity consumption and greenhouse gas (GHG) emissions reductions. We analyze the costs and benefits of several options to improve the efficiency of ceiling fans and assess the global potential for electricity savings and GHG emission reductions with more detailed assessments for India, China, and the U.S. We find that ceiling fan efficiency can be cost-effectively improved by at least 50% using commercially available technology. If these efficiency improvements are implemented in all ceiling fans sold by 2020, 70 terrawatt hours per year (TWh/year) could be saved and 25 million metric tons of carbon dioxide (CO2) emissions per year could be avoided, globally. We assess how policies and programs such as standards, labels, and financial incentives can be used to accelerate the adoption of efficient ceiling fans in order to realize this savings potential.

  13. Grinding efficiency improvement of hydraulic cylinders parts for mining equipment

    Directory of Open Access Journals (Sweden)

    Korotkov Aleksandr

    2017-01-01

    Full Text Available The aim of the article is to find out ways to improve parts treatment and components of mining equipment on the example of hydraulic cylinders parts, used as pillars for mine roof supports, and other actuator mechanisms. In the course of the research work methods of machine retaining devices design were used, the scientific approaches for the selection of progressive grinding schemes were applied; theoretical and practical experience in the design and production of new constructions of grinding tools was used. As a result of this work it became possible to create a progressive construction of a machine retaining device for grinding of large parts of hydraulic cylinders, to apply an effective scheme of rotary abrasive treatment, to create and implement new design of grinding tools by means of grains with controllable shape and orientation. Implementation of the results obtained in practice will improve the quality and performance of repairing and manufacturing of mining equipment.

  14. Improving Energy Efficiency In Thermal Oil Recovery Surface Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Murthy Nadella, Narayana

    2010-09-15

    Thermal oil recovery methods such as Cyclic Steam Stimulation (CSS), Steam Assisted Gravity Drainage (SAGD) and In-situ Combustion are being used for recovering heavy oil and bitumen. These processes expend energy to recover oil. The process design of the surface facilities requires optimization to improve the efficiency of oil recovery by minimizing the energy consumption per barrel of oil produced. Optimization involves minimizing external energy use by heat integration. This paper discusses the unit processes and design methodology considering thermodynamic energy requirements and heat integration methods to improve energy efficiency in the surface facilities. A design case study is presented.

  15. Nanocellulose-based Translucent Diffuser for Optoelectronic Device Applications with Dramatic Improvement of Light Coupling.

    Science.gov (United States)

    Wu, Wei; Tassi, Nancy G; Zhu, Hongli; Fang, Zhiqiang; Hu, Liangbing

    2015-12-09

    Nanocellulose is a biogenerated and biorenewable organic material. Using a process based on 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)/NaClO/NaBr system, a highly translucent and light-diffusive film consisting of many layers of nanocellulose fibers and wood pulp microfibers was made. The film demonstrates a combination of large optical transmittance of ∼90% and tunable diffuse transmission of up to ∼78% across the visible and near-infrared spectra. The detailed characterizations of the film indicate the combination of high optical transmittance and haze is due to the film's large packing density and microstructured surface. The superior optical properties make the film a translucent light diffuser and applicable for improving the efficiencies of optoelectronic devices such as thin-film silicon solar cells and organic light-emitting devices.

  16. Direct mounted photovoltaic device with improved adhesion and method thereof

    Science.gov (United States)

    Boven, Michelle L; Keenihan, James R; Lickly, Stan; Brown, Jr., Claude; Cleereman, Robert J; Plum, Timothy C

    2014-12-23

    The present invention is premised upon a photovoltaic device suitable for directly mounting on a structure. The device includes an active portion including a photovoltaic cell assembly having a top surface portion that allows transmission of light energy to a photoactive portion of the photovoltaic device for conversion into electrical energy and a bottom surface having a bottom bonding zone; and an inactive portion immediately adjacent to and connected to the active portion, the inactive portion having a region for receiving a fastener to connect the device to the structure and having on a top surface, a top bonding zone; wherein one of the top and bottom bonding zones comprises a first bonding element and the other comprises a second bonding element, the second bonding element designed to interact with the first bonding element on a vertically overlapped adjacent photovoltaic device to bond the device to such adjacent device or to the structure.

  17. A broadband high-efficiency Doherty power amplifier using symmetrical devices

    Science.gov (United States)

    Cheng, Zhiqun; Zhang, Ming; Li, Jiangzhou; Liu, Guohua

    2018-04-01

    This paper proposes a method for broadband and high-efficiency amplification of Doherty power amplifier (DPA) using symmetric devices. In order to achieve the perfect load modulation, the carrier amplifier output circuit total power length is designed to odd multiple of 90°, and the peak amplifier output total power length is designed to even multiple of 180°. The proposed method is demonstrated by designing a broadband high-efficiency DPA using identical 10-W packaged GaN HEMT devices. Measurement results show that over 51% drain efficiency is achieved at 6-dB back-off power, over the frequency band of 1.9–2.4 GHz. Project supported by the National Natural Science Foundation of China (No. 60123456), the Zhejiang Provincial Natural Science Foundation of China (No. LZ16F010001), and the Zhejiang Provincial Public Technology Research Project (No. 2016C31070).

  18. SOEC efficiency and cost improvement Part 1 and 2

    International Nuclear Information System (INIS)

    Yildiz, B.; Chang, K.-C.; Meyers, D. J.; You, H.; Carter, J.D.; Elam, J.W.; Honegger, D.A.; Libera, J.A.; Pellin, M.J.

    2007-01-01

    Part I: Electrochemical and X-ray Characterization of Solid-Oxide Electrolysis Cell Oxygen Electrodes on Electrolyte Substrates--The governing reaction mechanisms, and the electrode and electrolyte material compositions and structures, that controls the efficiency and durability of the solid oxide electrolysis cells (SOEC) need to be identified and well-understood for a significant improvement in nuclear hydrogen production using high temperature steam electrolysis. ANL conducted experimental analysis of SOEC electrolyte and electrodes to progress in this objective. Our study on the oxygen electrode focused on specifically the effect of electrode crystal structure on its electrochemical performance, and the evolution of the electronic and structural properties of the electrodes while under electrochemical conditions and high temperature. We found through electrochemical impedance spectroscopy experiments that, while different crystal orientations in La 0.8 Sr 0.2 MnO 3+d (LSM) show different initial performance and different electrochemical activation under SOEC conditions, a good mixed ionic electronic conductor La 0.8 Sr 0.2 CoO 3+d (LSC) does not seem to exhibit similar variations. Our in-situ x-ray and electrochemical measurements at the Advanced Photon Source of ANL have identified the chemical states of the A-site elements of the doped lanthanum manganite electrodes. We found that the changes in the concentration and in the electronic state of the La and Sr (the A-site elements of the perovskite) occurring only at the top airelectrode film interface can be responsible from the electrochemical improvement of the SOEC anode under DC current. Our observation related to the La chemical state change is unexpected and probably unique to the electrochemical current-conditioning. Part II: Progress Towards the Atomic Layer Deposition of Lanthanum Strontium Manganate--Lanthanum strontium manganate (LSM) is the most commonly used cathode material for solid oxide fuel

  19. Efficiency Improvement and Quality Initiatives Application in Financial Institutions

    Directory of Open Access Journals (Sweden)

    MSc. Ajtene Avdullahi

    2015-06-01

    Full Text Available Financial institutions in today’s economy have no longer the luxury to improve profit simply by increasing revenue. These firms, due to the significant measuring reductions in the financial services industry needed to improve operational efficiencies and merely support existing processes with fewer resources. This paper explains the benefits of Lean, Six Sigma, Total Quality Management and Lean Six Sigma that have improved organization's performance, by cutting costs and waste, improving their products or services, increasing profitability as well as enhancing customer satisfaction. The applicability of quality management practices in financial institutions in Kosovo is presented and also their efficiency and effectiveness. By analyzing data from Raiffeisen Bank Kosovo, this paper highlights the benefits of Individual and Micro companies customer segment as the result of organizational change and successful application of quality initiatives from financial institutions in Kosovo.

  20. Supply Chain Management for Improved Energy Efficiency: Review and Opportunities

    Directory of Open Access Journals (Sweden)

    Beatrice Marchi

    2017-10-01

    Full Text Available Energy efficiency represents a key resource for economic and social development, providing substantial benefits to different stakeholders, ranging from the entities which develop energy efficient measures to everyone in society. In addition to cost savings, multiple benefits can be achieved by supporting a better alignment between energy issues and strategic business priorities: e.g., improved competitiveness, profitability, quality, etc. Thus, energy efficiency can be a strategic advantage, not just a marginal issue, for companies. However, most firms, especially small and medium enterprises (SMEs, face many problems and, in some cases, hostility when trying to effectively implement energy efficiency actions. The most dominant barriers are the access to capital and the lack of awareness (especially in terms of life cycle cost effects. The supply chain viewpoint represents one of the main opportunities for overcoming those barriers and improving energy performance even for weaker companies. Since the current literature on energy efficiency and practical approaches to ensure energy efficiency mainly focus on energy performance on a single-firm basis, this paper aims to provide a systematic review of papers on the integration of energy efficiency in supply chain design and management published in academic journal, thereby defining potential research streams to close the gaps in the literature. A number of literature reviews have been published focusing on specific aspects of sustainable or on green supply chain management; however, to the best of our knowledge, no review has focused on the energy efficiency issue. Firstly, the present paper shows how considering energy consumption in supply chain management can contribute to more energy-efficient processes from a systemic point of view. Then, the review methodology used is defined and the sampled papers are analyzed and categorized based on the different approaches they propose. From these

  1. Improving radiation use efficiency in greenhouse production systems

    OpenAIRE

    Li, Tao

    2015-01-01

    SUMMARY A large increase in agricultural production is needed to feed the increasing world population with their increasing demand per capita. However, growing competition for arable land, water, energy, and the degradation of the environment impose challenges to improve crop production. Hence agricultural production efficiency needs to increase. Greenhouses provide the possibility to create optimal growth conditions for crops, thereby improving production and product quality. Light is the dr...

  2. Very high efficiency phosphorescent organic light-emitting devices by using rough indium tin oxide

    International Nuclear Information System (INIS)

    Zhang, Yingjie; Aziz, Hany

    2014-01-01

    The efficiency of organic light-emitting devices (OLEDs) is shown to significantly depend on the roughness of the indium tin oxide (ITO) anode. By using rougher ITO, light trapped in the ITO/organic wave-guided mode can be efficiently extracted, and a light outcoupling enhancement as high as 40% is achieved. Moreover, contrary to expectations, the lifetime of OLEDs is not affected by ITO roughness. Finally, an OLED employing rough ITO anode that exhibits a current efficiency of 56 cd/A at the remarkably high brightness of 10 5  cd/m 2 is obtained. This represents the highest current efficiency at such high brightness to date for an OLED utilizing an ITO anode, without any external light outcoupling techniques. The results demonstrate the significant efficiency benefits of using ITO with higher roughness in OLEDs.

  3. Very high efficiency phosphorescent organic light-emitting devices by using rough indium tin oxide

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yingjie; Aziz, Hany, E-mail: h2aziz@uwaterloo.ca [Department of Electrical and Computer Engineering and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1 (Canada)

    2014-07-07

    The efficiency of organic light-emitting devices (OLEDs) is shown to significantly depend on the roughness of the indium tin oxide (ITO) anode. By using rougher ITO, light trapped in the ITO/organic wave-guided mode can be efficiently extracted, and a light outcoupling enhancement as high as 40% is achieved. Moreover, contrary to expectations, the lifetime of OLEDs is not affected by ITO roughness. Finally, an OLED employing rough ITO anode that exhibits a current efficiency of 56 cd/A at the remarkably high brightness of 10{sup 5} cd/m{sup 2} is obtained. This represents the highest current efficiency at such high brightness to date for an OLED utilizing an ITO anode, without any external light outcoupling techniques. The results demonstrate the significant efficiency benefits of using ITO with higher roughness in OLEDs.

  4. Wastewater treatment facilities: Energy efficient improvements and cogeneration

    International Nuclear Information System (INIS)

    Kunkle, R.; Gray, R.; Delzel, D.

    1992-10-01

    The Washington State Energy Office (WSEO) has worked with both the Bonneville Power Administration (BPA) and the US Department of Energy to provide technical and financial assistance to local governments. Based on a recent study conducted by Ecotope for WSEO, local governments spend an estimated $45 million on utility bills statewide. Water and wastewater facilities account for almost a third of this cost. As a result, WSEO decided to focus its efforts on the energy intensive water and wastewater sector. The ultimate goal of this project was to develop mechanisms to incorporate energy efficiency improvements into wastewater treatment facilities in retrofits and during upgrades, remodels, and new construction. Project activities included the following: The review of the existing regulatory environment for treatment system construction, A summary of financing options for efficiency improvements in treatment facilities, A literature review of energy efficiency opportunities in treatment plants, Survey and site visits to characterize existing facilities in Washington State, Estimates of the energy efficiency and cogeneration potential in the sector, and A case study to illustrate the implementation of an efficiency improvement in a treatment facility

  5. Scaling production and improving efficiency in DEA: an interactive approach

    Science.gov (United States)

    Rödder, Wilhelm; Kleine, Andreas; Dellnitz, Andreas

    2017-10-01

    DEA models help a DMU to detect its (in-)efficiency and to improve activities, if necessary. Efficiency is only one economic aim for a decision-maker; however, up- or downsizing might be a second one. Improving efficiency is the main topic in DEA; the long-term strategy towards the right production size should attract our attention as well. Not always the management of a DMU primarily focuses on technical efficiency but rather is interested in gaining scale effects. In this paper, a formula for returns to scale (RTS) is developed, and this formula is even applicable for interior points of technology. Particularly, technical and scale inefficient DMUs need sophisticated instruments to improve their situation. Considering RTS as well as efficiency, in this paper, we give an advice for each DMU to find an economically reliable path from its actual situation to better activities and finally to most productive scale size (mpss), perhaps. For realizing this path, we propose an interactive algorithm, thus harmonizing the scientific findings and the interests of the management. Small numerical examples illustrate such paths for selected DMUs; an empirical application in theatre management completes the contribution.

  6. Efficient Work Team Scheduling: Using Psychological Models of Knowledge Retention to Improve Code Writing Efficiency

    Directory of Open Access Journals (Sweden)

    Michael J. Pelosi

    2014-12-01

    Full Text Available Development teams and programmers must retain critical information about their work during work intervals and gaps in order to improve future performance when work resumes. Despite time lapses, project managers want to maximize coding efficiency and effectiveness. By developing a mathematically justified, practically useful, and computationally tractable quantitative and cognitive model of learning and memory retention, this study establishes calculations designed to maximize scheduling payoff and optimize developer efficiency and effectiveness.

  7. An Efficient and Secure m-IPS Scheme of Mobile Devices for Human-Centric Computing

    Directory of Open Access Journals (Sweden)

    Young-Sik Jeong

    2014-01-01

    Full Text Available Recent rapid developments in wireless and mobile IT technologies have led to their application in many real-life areas, such as disasters, home networks, mobile social networks, medical services, industry, schools, and the military. Business/work environments have become wire/wireless, integrated with wireless networks. Although the increase in the use of mobile devices that can use wireless networks increases work efficiency and provides greater convenience, wireless access to networks represents a security threat. Currently, wireless intrusion prevention systems (IPSs are used to prevent wireless security threats. However, these are not an ideal security measure for businesses that utilize mobile devices because they do not take account of temporal-spatial and role information factors. Therefore, in this paper, an efficient and secure mobile-IPS (m-IPS is proposed for businesses utilizing mobile devices in mobile environments for human-centric computing. The m-IPS system incorporates temporal-spatial awareness in human-centric computing with various mobile devices and checks users’ temporal spatial information, profiles, and role information to provide precise access control. And it also can extend application of m-IPS to the Internet of things (IoT, which is one of the important advanced technologies for supporting human-centric computing environment completely, for real ubiquitous field with mobile devices.

  8. Efficient white organic light-emitting devices based on blue, orange, red phosphorescent dyes

    International Nuclear Information System (INIS)

    Chen Ping; Duan Yu; Xie Wenfa; Zhao Yi; Hou Jingying; Liu Shiyong; Zhang Liying; Li Bin

    2009-01-01

    We demonstrate efficient white organic light-emitting devices (WOLEDs) based on an orange phosphorescent iridium complex bis(2-(2-fluorphenyl)-1,3-benzothiozolato-N, C 2' )iridium(acetylacetonate) in combination with blue phosphorescent dye bis[(4, 6-difluorophenyl)-pyridinato-N,C 2 )](picolinato) Ir(III) and red phosphorescent dye bis[1-(phenyl)isoquinoline] iridium (III) acetylanetonate. By introducing a thin layer of 4, 7-diphenyl-1,10-phenanthroline between blue and red emission layers, the diffusion of excitons is confined and white light can be obtained. WOLEDs with the interlayer all have a higher colour rendering index (>82) than the device without it (76). One device has the maximum current efficiency of 17.6 cd A -1 and a maximum luminance of 39 050 cd m -2 . The power efficiency is 8.7 lm W -1 at 100 cd m -2 . Furthermore, the device has good colour stability and the CIE coordinates just change from (0.394, 0.425) to (0.390, 0.426) with the luminance increasing from 630 to 4200 cd m -2 .

  9. A new device to test cutting efficiency of mechanical endodontic instruments

    Science.gov (United States)

    Rubini, Alessio Giansiracusa; Plotino, Gianluca; Al-Sudani, Dina; Grande, Nicola M.; Putorti, Ermanno; Sonnino, GianPaolo; Cotti, Elisabetta; Testarelli, Luca; Gambarini, Gianluca

    2014-01-01

    Background The purpose of the present study was to introduce a new device specifically designed to evaluate the cutting efficiency of mechanically driven endodontic instruments. Material/Methods Twenty new Reciproc R25 (VDW, Munich, Germany) files were used to be investigated in the new device developed to test the cutting ability of endodontic instruments. The device consists of a main frame to which a mobile plastic support for the hand-piece is connected and a stainless-steel block containing a Plexiglas block against which the cutting efficiency of the instruments was tested. The length of the block cut in 1 minute was measured in a computerized program with a precision of 0.1mm. The instruments were activated by using a torque-controlled motor (Silver Reciproc; VDW, Munich, Germany) in a reciprocating movement by the “Reciproc ALL” program (Group 1) and in counter-clockwise rotation at 300 rpm (Group 2). Mean and standard deviations of each group were calculated and data were statistically analyzed with a one-way ANOVA test (P0.05). Conclusions The cutting testing device evaluated in the present study was reliable and easy to use and may be effectively used to test cutting efficiency of both rotary and reciprocating mechanical endodontic instruments. PMID:24603777

  10. An efficient enzyme-powered micromotor device fabricated by cyclic alternate hybridization assembly for DNA detection.

    Science.gov (United States)

    Fu, Shizhe; Zhang, Xueqing; Xie, Yuzhe; Wu, Jie; Ju, Huangxian

    2017-07-06

    An efficient enzyme-powered micromotor device was fabricated by assembling multiple layers of catalase on the inner surface of a poly(3,4-ethylenedioxythiophene and sodium 4-styrenesulfonate)/Au microtube (PEDOT-PSS/Au). The catalase assembly was achieved by programmed DNA hybridization, which was performed by immobilizing a designed sandwich DNA structure as the sensing unit on the PEDOT-PSS/Au, and then alternately hybridizing with two assisting DNA to bind the enzyme for efficient motor motion. The micromotor device showed unique features of good reproducibility, stability and motion performance. Under optimal conditions, it showed a speed of 420 μm s -1 in 2% H 2 O 2 and even 51 μm s -1 in 0.25% H 2 O 2 . In the presence of target DNA, the sensing unit hybridized with target DNA to release the multi-layer DNA as well as the multi-catalase, resulting in a decrease of the motion speed. By using the speed as a signal, the micromotor device could detect DNA from 10 nM to 1 μM. The proposed micromotor device along with the cyclic alternate DNA hybridization assembly technique provided a new path to fabricate efficient and versatile micromotors, which would be an exceptional tool for rapid and simple detection of biomolecules.

  11. Improving STEM Undergraduate Education with Efficient Learning Design

    DEFF Research Database (Denmark)

    Godsk, Mikkel

    2018-01-01

    The project investigates the potential of Learning Design for efficiently improving STEM undergraduate education with technology. In order to investigate this potential, the project consists of two main studies at Aarhus University: a study of the perspectives of the main stakeholders on Learning...... Design uptake. The project concludes that it is possible to improve STEM undergraduate education with Learning Design for technology-enhanced learning efficiently and that Efficient Learning Design provides a useful concept for qualifying educational decisions....... provided by technology-enhanced learning based on Learning Design, and in particular students’ learning was of a high common interest. However, only the educators were directly interested in Learning Design and its support for design, reuse in their practice and to inform pedagogy. A holistic concept...

  12. Improved production efficiency in cattle to reduce their carbon ...

    African Journals Online (AJOL)

    p2492989

    Keywords: Methane, global warming, greenhouse gas, crossbreeding, residual feed intake, feed efficiency. #Corresponding ... improved production per constant unit, crossbreeding and selection for residual feed intake. ... convert such a measure into kg calf produced per kg CO2 equivalent (CH4 can be converted to a CO2.

  13. Energy efficiency improvements in ammonia production--perspectives and uncertainties

    International Nuclear Information System (INIS)

    Rafiqul, Islam; Weber, Christoph; Lehmann, Bianca; Voss, Alfred

    2005-01-01

    The paper discusses the energy consumption and energy saving potential for a major energy-intensive product in the chemical industry-ammonia, based on technologies currently in use and possible process improvements. The paper consists of four parts. In the first part, mainly references to various ammonia production technologies are given. Energy consumption, emissions and saving potentials are discussed in the second part. Thereby, the situation in Europe, the US and India is highlighted and various data sources are compared. In the third part of the paper, a novel approach for modeling energy efficiency improvements is described that accounts for uncertainties and unobserved heterogeneity in the production processes. Besides new investments, revamping investments are also included in the modeling and the development of the production stock is accounted for. Finally, in the fourth part, this approach is applied to the modeling of energy efficiency improvements and CO 2 emission reductions in ammonia production. Thereby, considerable improvements in specific energy use and CO 2 emissions are found in the reference scenario, yet under the assumption of high oil and gas prices, a partial switch to coal based technologies is expected which lowers notably the CO 2 efficiency. Introduction of a CO 2 penalty under a certificate trading or other regime is on contrary found to foster energy efficiency and the use of low carbon technologies

  14. Does Competition Improve Public School Efficiency? A Spatial Analysis

    Science.gov (United States)

    Misra, Kaustav

    2010-01-01

    Proponents of educational reform often call for policies to increase competition between schools. It is argued that market forces naturally lead to greater efficiencies, including improved student learning, when schools face competition. In many parts of the country, public schools experience significant competition from private schools; however,…

  15. Solution for Improve the Efficiency of Solar Photovoltaic Installation

    OpenAIRE

    Petru Chioncel; Cristian Paul Chioncel; Nicoleta Gillich

    2013-01-01

    This paper present a solution for improving efficiency of solar photovoltaic installation, realized with fixed solar photovoltaic modules, placed in solar parks or individual installations. The proposed solution to increase the radiation on the solar photovoltaic panels is to use some thin plates covered with a reflective blanket, mounted in front of the solar photovoltaic modules, with the possibility of their adjustment.

  16. Improvement of a device for region radiation survey

    International Nuclear Information System (INIS)

    Poltinnikov, S.A.

    1978-01-01

    The electromechnanical device based on coding the turning angle of an automobile wheel by the number of electric pulses controlling the step motor of a film gate of gamma radiometer is proposed. The device is intended for automatizing recordings of gamma-radiation levels depending on a certain distance in a given terrain. The device has been tested at car speeds from 10 to 80 km/hr

  17. Improvement of efficiency roll-off in blue phosphorescence OLED using double dopants emissive layer

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Seung Il; Yoon, Ju An; Kim, Nam Ho; Kim, Jin Wook; Kang, Jin Sung; Moon, Chang-Bum [Department of Green Energy & Semiconductor Engineering, Hoseo University, Asan (Korea, Republic of); Kim, Woo Young, E-mail: wykim@hoseo.edu [Department of Green Energy & Semiconductor Engineering, Hoseo University, Asan (Korea, Republic of); Department of Engineering Physics, McMaster University, Hamilton, Ontario L8S 4L7 (Canada)

    2015-04-15

    Blue phosphorescent organic light-emitting diodes (PHOLEDs) were fabricated using double dopants FIrpic and FIr6 in emissive layer (EML) with structure of ITO/NPB (700 Å)/mCP:FIrpic-8%:FIr6-x% (300 Å)/TPBi (300 Å)/Liq (20 Å)/Al (1200 Å). We optimized concentration of the second dopant FIr6 in the presence of a fixed FIrpic to observe its effect on electrical performance of PHOLED device. 24.8 cd/A of luminous efficiency was achieved by the device with dopant ratio of 8%FIrpic:4%FIr6 in EML. Efficiency roll-off was also improved 20% compared to the PHOLED device singly dopped with FIrpic or FIr6 only. Second doping proved its effect in stabilizing charge balance in EML and enhancing energy transfer of triplet excitons between two dopants. - Highlights: • We fabricated blue PHOLED with double blue phosphorescent dopants in single EML. • Efficiency roll-off was improved by using double dopant in single EML. • The host–dopant transfer is discussed by analyzing the photo-absorption and photoluminescence. • The spectroscopic analysis using multi-peak fits with a Gaussian function.

  18. Probabilistic analysis of the efficiency of the damping devices against nuclear fuel container falling

    Science.gov (United States)

    Králik, Juraj

    2017-07-01

    The paper presents the probabilistic and sensitivity analysis of the efficiency of the damping devices cover of nuclear power plant under impact of the container of nuclear fuel of type TK C30 drop. The finite element idealization of nuclear power plant structure is used in space. The steel pipe damper system is proposed for dissipation of the kinetic energy of the container free fall. The experimental results of the shock-damper basic element behavior under impact loads are presented. The Newmark integration method is used for solution of the dynamic equations. The sensitivity and probabilistic analysis of damping devices was realized in the AntHILL and ANSYS software.

  19. Improvement in Device Performance and Reliability of Organic Light-Emitting Diodes through Deposition Rate Control

    Directory of Open Access Journals (Sweden)

    Shun-Wei Liu

    2014-01-01

    Full Text Available We demonstrated a fabrication technique to reduce the driving voltage, increase the current efficiency, and extend the operating lifetime of an organic light-emitting diode (OLED by simply controlling the deposition rate of bis(10-hydroxybenzo[h]qinolinato beryllium (Bebq2 used as the emitting layer and the electron-transport layer. In our optimized device, 55 nm of Bebq2 was first deposited at a faster deposition rate of 1.3 nm/s, followed by the deposition of a thin Bebq2 (5 nm layer at a slower rate of 0.03 nm/s. The Bebq2 layer with the faster deposition rate exhibited higher photoluminescence efficiency and was suitable for use in light emission. The thin Bebq2 layer with the slower deposition rate was used to modify the interface between the Bebq2 and cathode and hence improve the injection efficiency and lower the driving voltage. The operating lifetime of such a two-step deposition OLED was 1.92 and 4.6 times longer than that of devices with a single deposition rate, that is, 1.3 and 0.03 nm/s cases, respectively.

  20. Improving Security in Bring Your Own Device (BYOD) Environment by Controlling Access

    OpenAIRE

    Muhammad, M.A.; Zadeh, P.B.; Ayesh, Aladdin, 1972-

    2017-01-01

    With the rapid increase in smartphones and tablets, Bring Your Own Devices (BYOD) has simplified computing by introducing the use of personally owned devices. These devices can be utilised in accessing business enterprise contents and networks. The effectiveness of BYOD offers several business benefits like employee job satisfaction, increased job efficiency and flexibility. However, allowing employees to bring their own devices could lead to a plethora of security issues; like data theft, un...

  1. Improved Resolution Optical Time Stretch Imaging Based on High Efficiency In-Fiber Diffraction.

    Science.gov (United States)

    Wang, Guoqing; Yan, Zhijun; Yang, Lei; Zhang, Lin; Wang, Chao

    2018-01-12

    Most overlooked challenges in ultrafast optical time stretch imaging (OTSI) are sacrificed spatial resolution and higher optical loss. These challenges are originated from optical diffraction devices used in OTSI, which encode image into spectra of ultrashort optical pulses. Conventional free-space diffraction gratings, as widely used in existing OTSI systems, suffer from several inherent drawbacks: limited diffraction efficiency in a non-Littrow configuration due to inherent zeroth-order reflection, high coupling loss between free-space gratings and optical fibers, bulky footprint, and more importantly, sacrificed imaging resolution due to non-full-aperture illumination for individual wavelengths. Here we report resolution-improved and diffraction-efficient OTSI using in-fiber diffraction for the first time to our knowledge. The key to overcome the existing challenges is a 45° tilted fiber grating (TFG), which serves as a compact in-fiber diffraction device offering improved diffraction efficiency (up to 97%), inherent compatibility with optical fibers, and improved imaging resolution owning to almost full-aperture illumination for all illumination wavelengths. 50 million frames per second imaging of fast moving object at 46 m/s with improved imaging resolution has been demonstrated. This conceptually new in-fiber diffraction design opens the way towards cost-effective, compact and high-resolution OTSI systems for image-based high-throughput detection and measurement.

  2. Tungsten oxides as interfacial layers for improved performance in hybrid optoelectronic devices

    International Nuclear Information System (INIS)

    Vasilopoulou, M.; Palilis, L.C.; Georgiadou, D.G.; Argitis, P.; Kennou, S.; Kostis, I.; Papadimitropoulos, G.; Stathopoulos, N.A.; Iliadis, A.A.; Konofaos, N.; Davazoglou, D.; Sygellou, L.

    2011-01-01

    Tungsten oxide (WO 3 ) films with thicknesses ranging from 30 to 100 nm were grown by Hot Filament Vapor Deposition (HFVD). Films were studied by X-Ray Photoemission Spectroscopy (XPS) and were found to be stoichiometric. The surface morphology of the films was characterized by Atomic Force Microscopy (AFM). Samples had a granular form with grains in the order of 100 nm. The surface roughness was found to increase with film thickness. HFVD WO 3 films were used as conducting interfacial layers in advanced hybrid organic-inorganic optoelectronic devices. Hybrid-Organic Light Emitting Diodes (Hy-OLEDs) and Organic Photovoltaics (Hy-OPVs) were fabricated with these films as anode and/or as cathode interfacial conducting layers. The Hy-OLEDs showed significantly higher current density and a lower turn-on voltage when a thin WO 3 layer was inserted at the anode/polymer interface, while when inserted at the cathode/polymer interface the device performance was found to deteriorate. The improvement was attributed to a more efficient hole injection and transport from the Fermi level of the anode to the Highest Occupied Molecular Orbital (HOMO) of a yellow emitting copolymer (YEP). On the other hand, the insertion of a thin WO 3 layer at the cathode/polymer interface of Hy-OPV devices based on a polythiophene-fullerene bulk-heterojunction blend photoactive layer resulted in an increase of the produced photogenerated current, more likely due to improved electron extraction at the Al cathode.

  3. Efficient Adoption and Assessment of Multiple Process Improvement Reference Models

    Directory of Open Access Journals (Sweden)

    Simona Jeners

    2013-06-01

    Full Text Available A variety of reference models such as CMMI, COBIT or ITIL support IT organizations to improve their processes. These process improvement reference models (IRMs cover different domains such as IT development, IT Services or IT Governance but also share some similarities. As there are organizations that address multiple domains and need to coordinate their processes in their improvement we present MoSaIC, an approach to support organizations to efficiently adopt and conform to multiple IRMs. Our solution realizes a semantic integration of IRMs based on common meta-models. The resulting IRM integration model enables organizations to efficiently implement and asses multiple IRMs and to benefit from synergy effects.

  4. In Situ Preparation of Metal Halide Perovskite Nanocrystal Thin Films for Improved Light-Emitting Devices.

    Science.gov (United States)

    Zhao, Lianfeng; Yeh, Yao-Wen; Tran, Nhu L; Wu, Fan; Xiao, Zhengguo; Kerner, Ross A; Lin, YunHui L; Scholes, Gregory D; Yao, Nan; Rand, Barry P

    2017-04-25

    Hybrid organic-inorganic halide perovskite semiconductors are attractive candidates for optoelectronic applications, such as photovoltaics, light-emitting diodes, and lasers. Perovskite nanocrystals are of particular interest, where electrons and holes can be confined spatially, promoting radiative recombination. However, nanocrystalline films based on traditional colloidal nanocrystal synthesis strategies suffer from the use of long insulating ligands, low colloidal nanocrystal concentration, and significant aggregation during film formation. Here, we demonstrate a facile method for preparing perovskite nanocrystal films in situ and that the electroluminescence of light-emitting devices can be enhanced up to 40-fold through this nanocrystal film formation strategy. Briefly, the method involves the use of bulky organoammonium halides as additives to confine crystal growth of perovskites during film formation, achieving CH 3 NH 3 PbI 3 and CH 3 NH 3 PbBr 3 perovskite nanocrystals with an average crystal size of 5.4 ± 0.8 nm and 6.4 ± 1.3 nm, respectively, as confirmed through transmission electron microscopy measurements. Additive-confined perovskite nanocrystals show significantly improved photoluminescence quantum yield and decay lifetime. Finally, we demonstrate highly efficient CH 3 NH 3 PbI 3 red/near-infrared LEDs and CH 3 NH 3 PbBr 3 green LEDs based on this strategy, achieving an external quantum efficiency of 7.9% and 7.0%, respectively, which represent a 40-fold and 23-fold improvement over control devices fabricated without the additives.

  5. Red organic light emitting devices with reduced efficiency roll-off behavior by using hybrid fluorescent/phosphorescent emission structure

    Energy Technology Data Exchange (ETDEWEB)

    Zheng Tianhang; Choy, Wallace C.H., E-mail: chchoy@eee.hku.h

    2010-11-01

    Organic light emitting device (OLED) with a fluorescence-interlayer-phosphorescence emissive structure (FIP EML) is proposed to solve efficiency roll-off issue effectively. By doping fluorescent emitter of 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl) -4H-pyran (DCJTB) and phosphorescent emitter of tris(1-phenylisoquinolinolato-C2,N)iridium(III) (Ir(piq){sub 3}) into the different regions of emission zone to form FIP EML in red OLED, an improvement of more than 20% in luminance efficiency roll-off compared with that of typical phosphorescent OLED with single EML in 10-500 mA/cm{sup 2} range has been obtained. Detailed mechanisms have been studied. Such improvement should be attributed to the distinct roles of the two emitters, where DCJTB mainly used to influence the carrier transport leading to an improved balance of charge carriers while Ir(piq){sub 3} functions as the radiative decay sites for most generated excitons. Meanwhile, with the help of the formation of FIP EML, the redistribution of excitons in recombination zone, the suppression of non-radiative exciton quenching processes and the elimination of energy transfer loss also contribute to the enhancement of efficiency roll-off. The method proposed here may provide a route to develop efficient OLED for high luminance applications.

  6. Direct mounted photovoltaic device with improved front clip

    Science.gov (United States)

    Keenihan, James R; Boven, Michelle; Brown, Jr., Claude; Gaston, Ryan S; Hus, Michael; Langmaid, Joe A; Lesniak, Mike

    2013-11-05

    The present invention is premised upon a photovoltaic assembly system for securing and/or aligning at least a plurality of vertically adjacent (overlapping) photovoltaic device assemblies to one another. The securing function being accomplished by a clip member that may be a separate component or integral to one or more of the photovoltaic device assemblies.

  7. Direct mounted photovoltaic device with improved side clip

    Science.gov (United States)

    Keenihan, James R; Boven, Michelle L; Brown, Jr., Claude; Eurich, Gerald K; Gaston, Ryan S; Hus, Michael

    2013-11-19

    The present invention is premised upon a photovoltaic assembly system for securing and/or aligning at least a plurality of vertically adjacent photovoltaic device assemblies to one another. The securing function being accomplished by a clip member that may be a separate component or integral to one or more of the photovoltaic device assemblies.

  8. Highly efficient white organic light-emitting devices consisting of undoped ultrathin yellow phosphorescent layer

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Shengqiang [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054 (China); Yu, Junsheng, E-mail: jsyu@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054 (China); Ma, Zhu; Zhao, Juan [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054 (China)

    2013-02-15

    High-efficiency white organic light-emitting devices (WOLEDs) based on an undoped ultrathin yellow light-emitting layer and a doped blue light-emitting layer were demonstrated. While the thickness of blue light-emitting layer, formed by doping a charge-trapping phosphor, iridium(III) bis(4 Prime ,6 Prime -difluorophenylpyridinato)tetrakis(1-pyrazolyl)borate (FIr6) in a wide bandgap host, was kept constant, the thickness of neat yellow emissive layer of novel phosphorescent material, bis[2-(4-tertbutylphenyl)benzothiazolato-N,C{sup 2 Prime }]iridium (acetylacetonate) [(t-bt){sub 2}Ir(acac)] was varied to optimize the device performance. The optimized device exhibited maximum luminance, current efficiency and power efficiency of 24,000 cd/m{sup 2} (at 15.2 V), 79.0 cd/A (at 1550 cd/m{sup 2}) and 40.5 lm/W (at 1000 cd/m{sup 2}), respectively. Besides, the white-light emission covered a wide range of visible spectrum, and the Commission Internationale de l'Eclairage coordinates were (0.32, 0.38) with a color temperature of 5800 K at 8 V. Moreover, high external quantum efficiency was also obtained in the high-efficiency WOLEDs. The performance enhancement was attributed to the proper thickness of (t-bt){sub 2}Ir(acac) layer that enabled adequate current density and enough phosphorescent dye to trap electrons. - Highlights: Black-Right-Pointing-Pointer Highly efficient WOLEDs based on two complementary layers were fabricated. Black-Right-Pointing-Pointer The yellow emissive layer was formed by utilizing undoping system. Black-Right-Pointing-Pointer The blue emissive layer was made by host-guest doping system. Black-Right-Pointing-Pointer The thickness of the yellow emissive layer was varied to make device optimization. Black-Right-Pointing-Pointer The optimized device achieved high power efficiency of 40.5 lm/W.

  9. Options to improve energy efficiency for educational building

    Science.gov (United States)

    Jahan, Mafruha

    The cost of energy is a major factor that must be considered for educational facility budget planning purpose. The analysis of energy related issues and options can be complex and requires significant time and detailed effort. One way to facilitate the inclusion of energy option planning in facility planning efforts is to utilize a tool that allows for quick appraisal of the facility energy profile. Once such an appraisal is accomplished, it is then possible to rank energy improvement options consistently with other facility needs and requirements. After an energy efficiency option has been determined to have meaningful value in comparison with other facility planning options, it is then possible to utilize the initial appraisal as the basis for an expanded consideration of additional facility and energy use detail using the same analytic system used for the initial appraisal. This thesis has developed a methodology and an associated analytic model to assist in these tasks and thereby improve the energy efficiency of educational facilities. A detailed energy efficiency and analysis tool is described that utilizes specific university building characteristics such as size, architecture, envelop, lighting, occupancy, thermal design which allows reducing the annual energy consumption. Improving the energy efficiency of various aspects of an educational building's energy performance can be complex and can require significant time and experience to make decisions. The approach developed in this thesis initially assesses the energy design for a university building. This initial appraisal is intended to assist administrators in assessing the potential value of energy efficiency options for their particular facility. Subsequently this scoping design can then be extended as another stage of the model by local facility or planning personnel to add more details and engineering aspects to the initial screening model. This approach can assist university planning efforts to

  10. Process efficiency. Redesigning social networks to improve surgery patient flow.

    Science.gov (United States)

    Samarth, Chandrika N; Gloor, Peter A

    2009-01-01

    We propose a novel approach to improve throughput of the surgery patient flow process of a Boston area teaching hospital. A social network analysis was conducted in an effort to demonstrate that process efficiency gains could be achieved through redesign of social network patterns at the workplace; in conjunction with redesign of organization structure and the implementation of workflow over an integrated information technology system. Key knowledge experts and coordinators in times of crisis were identified and a new communication structure more conducive to trust and knowledge sharing was suggested. The new communication structure is scalable without compromising on coordination required among key roles in the network for achieving efficiency gains.

  11. Evaluation efficiency for mobile as discharge measurement device for partially filled circular channel

    Directory of Open Access Journals (Sweden)

    I.M.H. Rashwan

    2013-06-01

    Full Text Available Discharge measurement is an important step in engineering applications such as sewerage system, irrigation and drainage system. Mobile flume is a simple and low-cost discharge measuring device constructed of two pieces of pipes, one installed vertically inside the other. The circular mobile flume depends on the concept of developing a contracted zone to have a control section. To evaluate the efficiency of this type of device mathematical and experimental studies are presented. Specific energy, discharge and Froude number equations are used to develop mathematical model. Experimental work is carried out to measure the discharge values corresponding to the specific energy values. The experimental data is used to evaluate the mobile flume as a device to measure discharge. A new equation for the discharge coefficient is presented. This equation can be used to determined accurate discharge with knowing the contraction ratio and measured specific energy.

  12. Rotary powered device for bone marrow aspiration and biopsy yields excellent specimens quickly and efficiently.

    Science.gov (United States)

    Swords, Ronan T; Kelly, Kevin R; Cohen, Stephen C; Miller, Larry J; Philbeck, Thomas E; Hacker, Sander O; Spadaccini, Cathy J; Giles, Francis J; Brenner, Andrew J

    2010-06-01

    Recently, a new FDA-cleared battery powered bone marrow biopsy system was developed to allow operators access to the bone marrow space quickly and efficiently. A pre-clinical evaluation of the device (OnControl, Vidacare Corporation, San Antonio, TX, USA) on anesthetized pigs was conducted, in addition to a clinical evaluation in hematology clinic patients requiring a bone marrow biopsy. Twenty-six samples were collected from the swine model. No cellular artifact or thermal damage was reported in any of the samples obtained. For the clinical evaluation of the device, 16 patients were recruited. Mean time from needle contact with skin to needle removal was 38.5 +/- 13.94 seconds. No complications were reported. In this study, the manual and powered samples were equivalent in specimen quality. In the patients evaluated, the device was safe, easy to use and the mean procedural time was significantly faster than previously reported with a manual technique.

  13. Towards Efficient Spectral Converters through Materials Design for Luminescent Solar Devices.

    Science.gov (United States)

    McKenna, Barry; Evans, Rachel C

    2017-07-01

    Single-junction photovoltaic devices exhibit a bottleneck in their efficiency due to incomplete or inefficient harvesting of photons in the low- or high-energy regions of the solar spectrum. Spectral converters can be used to convert solar photons into energies that are more effectively captured by the photovoltaic device through a photoluminescence process. Here, recent advances in the fields of luminescent solar concentration, luminescent downshifting, and upconversion are discussed. The focus is specifically on the role that materials science has to play in overcoming barriers in the optical performance in all spectral converters and on their successful integration with both established (e.g., c-Si, GaAs) and emerging (perovskite, organic, dye-sensitized) cell types. Current challenges and emerging research directions, which need to be addressed for the development of next-generation luminescent solar devices, are also discussed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Atmospheric Pressure Chemical Vapor Deposition of CdTe for High-Efficiency Thin-Film PV Devices; Annual Report, 26 January 1998-25 January 1999

    Energy Technology Data Exchange (ETDEWEB)

    Meyers, P. V. [ITN Energy Systems, Wheat Ridge, Colorado (US); Kee, R.; Wolden, C.; Raja, L.; Kaydanov, V.; Ohno, T.; Collins, R.; Aire, M.; Kestner, J. [Colorado School of Mines, Golden, Colorado (US); Fahrenbruch, A. [ALF, Inc., Stanford, California (US)

    1999-09-30

    ITN's 3-year project, titled ''Atmospheric Pressure Chemical Vapor Deposition (APCVD) of CdTe for High-Efficiency Thin-Film Photovoltaic (PV) Devices,'' has the overall objectives of improving thin-film CdTe PV manufacturing technology and increasing CdTe PV device power conversion efficiency. CdTe deposition by APCVD employs the same reaction chemistry as has been used to deposit 16%-efficient CdTe PV films, i.e., close-spaced sublimation, but employs forced convection rather than diffusion as a mechanism of mass transport. Tasks of the APCVD program center on demonstrating APCVD of CdTe films, discovering fundamental mass-transport parameters, applying established engineering principles to the deposition of CdTe films, and verifying reactor design principles that could be used to design high-throughput, high-yield manufacturing equipment. Additional tasks relate to improved device measurement and characterization procedures that can lead to a more fundamental understanding of CdTe PV device operation, and ultimately, to higher device conversion efficiency and greater stability. Specifically, under the APCVD program, device analysis goes beyond conventional one-dimensional device characterization and analysis toward two-dimension measurements and modeling. Accomplishments of the first year of the APCVD subcontract include: selection of the Stagnant Flow Reactor design concept for the APCVD reactor, development of a detailed reactor design, performance of detailed numerical calculations simulating reactor performance, fabrication and installation of an APCVD reactor, performance of dry runs to verify reactor performance, performance of one-dimensional modeling of CdTe PV device performance, and development of a detailed plan for quantification of grain-boundary effects in polycrystalline CdTe devices.

  15. High-efficiency terahertz polarization devices based on the dielectric metasurface

    Science.gov (United States)

    Zhou, Jian; Wang, JingJing; Guo, Kai; Shen, Fei; Zhou, Qingfeng; Zhiping yin; Guo, Zhongyi

    2018-02-01

    Metasurfaces are composed of the subwavelength structures, which can be used to manipulate the amplitude, phase, and polarization of incident electromagnetic waves efficiently. Here, we propose a novel type of dielectric metasurface based on crystal Si for realizing to manipulate the terahertz wave, in which by varying the geometric sizes of the Si micro-bricks, the transmitting phase of the terahertz wave can almost span over the entire 2π range for both of the x-polarization and y-polarization simultaneously, while keeping the similarly high-transmission amplitudes (over 90%). At the frequency of 1.0 THz, we have successfully designed a series of controllable THz devices, such as the polarization-dependent beam splitter, polarization-independent beam deflector and the focusing lenses based on the designed metasurfaces. Our designs are easy to fabricate and can be promising in developing high-efficiency THz functional devices.

  16. Graphene-based vdW heterostructure Induced High-efficiency Thermoelectric Devices

    Science.gov (United States)

    Liang, Shijun; Ang, Lay Kee

    Thermoelectric material (TE) can convert the heat into electricity to provide green energy source and its performance is characterized by a figure of merit (ZT) parameter. Traditional TE materials only give ZT equal to around 1 at room temperature. But, it is believed that materials with ZT >3 will find wide applications at this low temperature range. Prior studies have implied that the interrelation between electric conductivity and lattice thermal conductivity renders the goal of engineering ZT of bulk materials to reach ZT >3. In this work, we propose a high-efficiency van del Waals (vdW) heterostructure-based thermionic device with graphene electrodes, which is able to harvest wasted heat (around 400K) based on the newly established thermionic emission law of graphene electrodes instead of Seebeck effect, to boost the efficiency of power generation over 10% around room temperature. The efficiency can be above 20% if the Schottky barrier height and cross-plane lattice thermal conductivity of transition metal dichacogenides (TMD) materials can be fine-engineered. As a refrigerator at 260 K, the efficiency is 50% to 80% of Carnot efficiency. Finally, we identify two TMD materials as the ideal candidates of graphene/TMD/graphene devices based on the state-of-art technology.

  17. An Efficient and Secure m-IPS Scheme of Mobile Devices for Human-Centric Computing

    OpenAIRE

    Jeong, Young-Sik; Lee, Jae Dong; Lee, Jeong-Bae; Jung, Jai-Jin; Park, Jong Hyuk

    2014-01-01

    Recent rapid developments in wireless and mobile IT technologies have led to their application in many real-life areas, such as disasters, home networks, mobile social networks, medical services, industry, schools, and the military. Business/work environments have become wire/wireless, integrated with wireless networks. Although the increase in the use of mobile devices that can use wireless networks increases work efficiency and provides greater convenience, wireless access to networks repre...

  18. Single-doped white organic light-emitting device with an external quantum efficiency over 20%.

    Science.gov (United States)

    Fleetham, Tyler; Ecton, Jeremy; Wang, Zixing; Bakken, Nathan; Li, Jian

    2013-05-14

    A white OLED with a maximum EQE of 20.1%, CIE coordinates of (0.33, 0.33) and CRI of 80 is fabricated based on platinum(II) bis(N-methyl-imidazolyl)benzene chloride (Pt-16). The device emission spectrum and the chemical structure of Pt-16 are shown in the inset of the efficiency versus luminance graph. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Betavoltaic Battery Conversion Efficiency Improvement Based on Interlayer Structures

    International Nuclear Information System (INIS)

    Li Da-Rang; Jiang Lan; Yin Jian-Hua; Lin Nai; Tan Yuan-Yuan

    2012-01-01

    Significant differences among the doping densities of PN junctions in semiconductors cause lattice mismatch and lattice defects that increase the recombination current of betavoltaic batteries. This extensively decreases the open circuit voltage and the short current, which results in low conversion efficiency. This study proposes P + PINN + -structure based betavoltaic batteries by adding an interlayer to typical PIN structures to improve conversion efficiency. Numerical simulations are conducted for the energy deposition of beta particles along the thickness direction in semiconductors. Based on this, 63 Ni-radiation GaAs batteries with PIN and P + PINN + structures are designed and fabricated to experimentally verify the proposed design. It turns out that the conversion efficiency of the betavoltaic battery with the proposed P + PINN + structure is about 1.45 times higher than that with the traditional PIN structure. (cross-disciplinary physics and related areas of science and technology)

  20. High-efficiency red electroluminescent device based on multishelled InP quantum dots.

    Science.gov (United States)

    Jo, Jung-Ho; Kim, Jong-Hoon; Lee, Ki-Heon; Han, Chang-Yeol; Jang, Eun-Pyo; Do, Young Rag; Yang, Heesun

    2016-09-01

    We report on the synthesis of highly fluorescent red-emitting InP quantum dots (QDs) and their application to the fabrication of a high-efficiency QD-light-emitting diode (QLED). The core/shell heterostructure of the QDs is elaborately tailored toward a multishelled structure with a composition-gradient ZnSeS intermediate shell and an outer ZnS shell. Using the resulting InP/ZnSeS/ZnS QDs as an emitting layer, all-solution-processible red InP QLEDs are fabricated with a hybrid multilayered device structure having an organic hole transport layer (HTL) and an inorganic ZnO nanoparticle electron transport layer. Two HTLs of poly(9-vinlycarbazole) or poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl))diphenyl-amine), whose hole mobilities are different by at least three orders of magnitude, are individually applied for QLED fabrication and such HTL-dependent device performances are compared. Our best red device displays exceptional figures of merit such as a maximum luminance of 2849  cd/m2, a current efficiency of 4.2  cd/A, and an external quantum efficiency of 2.5%.

  1. Energy efficiency improvement potentials for the cement industry in Ethiopia

    International Nuclear Information System (INIS)

    Tesema, Gudise; Worrell, Ernst

    2015-01-01

    The cement sector is one of the fast growing economic sectors in Ethiopia. In 2010, it consumed 7 PJ of primary energy. We evaluate the potential for energy savings and CO_2 emission reductions. We start by benchmarking the energy performance of 8 operating plants in 2010, and 12 plants under construction. The benchmarking shows that the energy intensity of local cement facilities is high, when compared to the international best practice, indicating a significant potential for energy efficiency improvement. The average electricity intensity and fuel intensity of the operating plants is 34% and 36% higher. For plants under construction, electricity use is 36% and fuel use 27% higher. We identified 26 energy efficiency measures. By constructing energy conservation supply curves, the energy-efficiency improvement potential is assessed. For the 8 operating plants in 2010, the cost-effective energy savings equal 11 GWh electricity and 1.2 PJ fuel, resulting in 0.1 Mt CO_2 emissions reduction. For the 20 cement plants expected to be in operation by 2020, the cost-effective energy saving potentials is 159 GWh for electricity and 7.2 PJ for fuel, reducing CO_2 emissions by about 0.6 Mt. We discuss key barriers and recommendations to realize energy savings. - Highlights: • The cement sector in Ethiopia is growing rapidly, using mainly imported fuels. • Benchmarking demonstrates a significant potential for energy efficiency improvement. • A large part of the energy efficiency potential can be achieved cost-effectively. • Ethiopia should ban the construction of obsolete vertical shaft kilns.

  2. Energy-Efficiency Improvement Opportunities for the Textile Industry

    Energy Technology Data Exchange (ETDEWEB)

    China Energy Group; Hasanbeigi, Ali

    2010-09-29

    The textile industry is one of the most complicated manufacturing industries because it is a fragmented and heterogeneous sector dominated by small and medium enterprises (SMEs). Energy is one of the main cost factors in the textile industry. Especially in times of high energy price volatility, improving energy efficiency should be a primary concern for textile plants. There are various energy-efficiency opportunities that exist in every textile plant, many of which are cost-effective. However, even cost-effective options often are not implemented in textile plants mostly because of limited information on how to implement energy-efficiency measures, especially given the fact that a majority of textile plants are categorized as SMEs and hence they have limited resources to acquire this information. Know-how on energy-efficiency technologies and practices should, therefore, be prepared and disseminated to textile plants. This guidebook provides information on energy-efficiency technologies and measures applicable to the textile industry. The guidebook includes case studies from textile plants around the world and includes energy savings and cost information when available. First, the guidebook gives a brief overview of the textile industry around the world, with an explanation of major textile processes. An analysis of the type and the share of energy used in different textile processes is also included in the guidebook. Subsequently, energy-efficiency improvement opportunities available within some of the major textile sub-sectors are given with a brief explanation of each measure. The conclusion includes a short section dedicated to highlighting a few emerging technologies in the textile industry as well as the potential for the use of renewable energy in the textile industry.

  3. Improved entropy encoding for high efficient video coding standard

    Directory of Open Access Journals (Sweden)

    B.S. Sunil Kumar

    2018-03-01

    Full Text Available The High Efficiency Video Coding (HEVC has better coding efficiency, but the encoding performance has to be improved to meet the growing multimedia applications. This paper improves the standard entropy encoding by introducing the optimized weighing parameters, so that higher rate of compression can be accomplished over the standard entropy encoding. The optimization is performed using the recently introduced firefly algorithm. The experimentation is carried out using eight benchmark video sequences and the PSNR for varying rate of data transmission is investigated. Comparative analysis based on the performance statistics is made with the standard entropy encoding. From the obtained results, it is clear that the originality of the decoded video sequence is preserved far better than the proposed method, though the compression rate is increased. Keywords: Entropy, Encoding, HEVC, PSNR, Compression

  4. Improvements in or relating to charge coupled devices

    International Nuclear Information System (INIS)

    Shannon, J.M.

    1980-01-01

    This invention relates to charge coupled devices for converting an electromagnetic radiation pattern in a certain wavelength range, particularly but not exclusively an infrared radiation pattern, into electrical signals. A semiconductor layer within this device can be of n-type silicon with a deep level impurity concentration present as proton bombardment induced defects in the crystal lattice or as an ion implanted concentration. (UK)

  5. Current trends for improving the design of membrane devices for photoautotrophic biosynthesis is light dependent microorganisms

    Directory of Open Access Journals (Sweden)

    A. A. Shevtsov

    2016-01-01

    Full Text Available Modern trends in improving the design of membrane devices for photoautotrophic biosynthesis dependent lighting microorganisms aimed at a significant increase in the productivity of valuable products from biomass of microalgae and obtaining on the basis of their individual useful substances (drugs used in various industries and medicine. In film devices effectively the processes of heat - and mass-exchange with the gas comes into contact with the culture fluid flowing as a film on a transparent film-forming surface is STI in its light intensity and autotrophic biosynthesis occurs only in the presence of a mixture of air with carbon dioxide. Thus, completely eliminated the accumulation of metabolic products due to their continuous removal from film culture liquid with the process gas, which is not typical for devices of other types. Small size membrane bioreactors may increase the degree of saturation of the liquid carbon dioxide with the possibility of changing the concentration of gas in the culture fluid and to ensure the cultivation of microorganisms with a specified biomass yield. At present up to date-developed a significant number of ways to ensure contact of the gas with the liquid (bubbling, gas-lift, mechanical stirring, jet, membrane, etc. on the basis of which an industrial bioreactor, with various "stress" effect. It is believed that for the cultivation of the most optimal are bioreactors with mechanical stirring of the liquid, which allow the greatest productivity of biomass. However, the applied model of a mechanical mixing device to create a work whose cavity of the bioreactor chaotic, disorganized mixing, which contributes to the emergence, insufficient for the sustenance of the cell cultures and microorganisms. Analysis of the interactions of the gas with the liquid film devices showed the need to create a new generation of bioreactor with intensive mass transfer without the possibility of limiting the productivity of

  6. Improved district heating substation efficiency with a new control strategy

    International Nuclear Information System (INIS)

    Gustafsson, Jonas; Delsing, Jerker; Deventer, Jan van

    2010-01-01

    In this paper, we describe a new alternative control approach for indirectly connected district heating substations. Simulations results showed that the new approach results in an increased ΔT across the substation. Results were obtained for both ideal and non-ideal operation of the system, meaning that less water must be pumped through the district heating network, and a higher overall fuel efficiency can be obtained in the district heating power plants. When a higher fuel efficiency is achieved, the usage of primary fuel sources can be reduced. Improved efficiency also increases the effective heat transfer capacity of a district heating network, allowing more customers to be connected to an existing network without increasing the heating plant or network capacity. Also, if combined heat and power plants are used to produce the heat, the increased ΔT will result in a further improved overall fuel efficiency, as more electricity can be produced with colder cooling water. The idea behind the new control method is to consider the temperature of the water supplying the district heating substation with heat, often referred to as the primary supply temperature. This represents a logical next step, as currently, the only parameter generally taken into account or measured when controlling the temperature level of the radiator circuit is the local outdoor temperature. In this paper we show how the primary supply temperature together with thermodynamic knowledge of the building can be used to maximize the ΔT across the district heating substation.

  7. Improving the efficiency of aerodynamic shape optimization procedures

    Science.gov (United States)

    Burgreen, Greg W.; Baysal, Oktay; Eleshaky, Mohamed E.

    1992-01-01

    The computational efficiency of an aerodynamic shape optimization procedure which is based on discrete sensitivity analysis is increased through the implementation of two improvements. The first improvement involves replacing a grid point-based approach for surface representation with a Bezier-Bernstein polynomial parameterization of the surface. Explicit analytical expressions for the grid sensitivity terms are developed for both approaches. The second improvement proposes the use of Newton's method in lieu of an alternating direction implicit (ADI) methodology to calculate the highly converged flow solutions which are required to compute the sensitivity coefficients. The modified design procedure is demonstrated by optimizing the shape of an internal-external nozzle configuration. A substantial factor of 8 decrease in computational time for the optimization process was achieved by implementing both of the design improvements.

  8. Solution for Improve the Efficiency of Solar Photovoltaic Installation

    Directory of Open Access Journals (Sweden)

    Petru Chioncel

    2013-01-01

    Full Text Available This paper present a solution for improving efficiency of solar photovoltaic installation, realized with fixed solar photovoltaic modules, placed in solar parks or individual installations. The proposed solution to increase the radiation on the solar photovoltaic panels is to use some thin plates covered with a reflective blanket, mounted in front of the solar photovoltaic modules, with the possibility of their adjustment.

  9. IMPROVING CO2 EFFICIENCY FOR RECOVERING OIL IN HETEROGENEOUS RESERVOIRS

    International Nuclear Information System (INIS)

    Grigg, Reid B.

    2002-01-01

    A three-year contract, DOE Contract No. DE-FG26-01BC15364 ''Improving CO 2 Efficiency for Recovering Oil in Heterogeneous Reservoirs,'' was started on September 28, 2001. This project examines three major areas in which CO 2 flooding can be improved: fluid and matrix interactions, conformance control/sweep efficiency, and reservoir simulation for improved oil recovery. This report discusses the activity during the six-month period covering January 1, 2002 through June 30, 2002 that covers the second and third fiscal quarters of the project's first year. Paper SPE 75178, ''Cost Reduction and Injectivity Improvements for CO 2 Foams for Mobility Control,'' has been presented and included in the proceedings of the SPE/DOE Thirteenth Symposium on Improved Oil Recovery, Tulsa, OK, April 13-17, 2002. During these two quarters of the project we have been working in several areas: reservoir fluid/rock interactions and their relationships to changing injectivity, producer survey on injectivity, and surfactant adsorption on quarried and reservoir core

  10. Electronic health records and cardiac implantable electronic devices: new paradigms and efficiencies.

    Science.gov (United States)

    Slotwiner, David J

    2016-10-01

    The anticipated advantages of electronic health records (EHRs)-improved efficiency and the ability to share information across the healthcare enterprise-have so far failed to materialize. There is growing recognition that interoperability holds the key to unlocking the greatest value of EHRs. Health information technology (HIT) systems including EHRs must be able to share data and be able to interpret the shared data. This requires a controlled vocabulary with explicit definitions (data elements) as well as protocols to communicate the context in which each data element is being used (syntactic structure). Cardiac implantable electronic devices (CIEDs) provide a clear example of the challenges faced by clinicians when data is not interoperable. The proprietary data formats created by each CIED manufacturer, as well as the multiple sources of data generated by CIEDs (hospital, office, remote monitoring, acute care setting), make it challenging to aggregate even a single patient's data into an EHR. The Heart Rhythm Society and CIED manufacturers have collaborated to develop and implement international standard-based specifications for interoperability that provide an end-to-end solution, enabling structured data to be communicated from CIED to a report generation system, EHR, research database, referring physician, registry, patient portal, and beyond. EHR and other health information technology vendors have been slow to implement these tools, in large part, because there have been no financial incentives for them to do so. It is incumbent upon us, as clinicians, to insist that the tools of interoperability be a prerequisite for the purchase of any and all health information technology systems.

  11. Study of the detective quantum efficiency for the kinestatic charge detector as a megavoltage imaging device

    Science.gov (United States)

    Samant, Sanjiv S.; Gopal, Arun; DiBianca, Frank A.

    2003-06-01

    Megavoltage x-ray imaging suffers from relatively poor contrast and spatial resolution compared to diagnostic kilovoltage x-ray imaging due to the dominant Compton scattering in the former. Recently available amorphous silicon/selenium based flat-panel imagers overcome many of the limitations of poor contrast and spatial resolution that affect conventional video based electronic portal imaging devices (EPIDs). An alternative technology is presented here: kinestatic charge detection (KCD). The KCD uses a slot photon beam, high-pressure gas (xenon, 100 atm) and a multi-ion rectangular chamber in scanning mode. An electric field is used to regulate the cation drift velocity. By matching the scanning speed with that of the cation drift, the cations remain static in the object frame of reference, allowing temporal integration of the signal. KCD imaging is characterized by reduced scatter and a high signal-to-noise ratio. Measurements and Monte Carlo simulations of modulation transfer function (MTF), noise power spectrum (NPS) and the detective quantum efficiency (DQE) of a prototype small field of view KCD detector (384 channels, 0.5 mm spacing) were carried out. Measurements yield DQE[0]=0.19 and DQE[0.5cy/mm]=0.01. KCD imaging is compared to film and commercial EPID systems using phantoms, with the KCD requiring an extremely low dose (0.1 cGy) per image. A proposed cylindrical chamber design with a higher ion-collection depth is expected to further improve image quality (DQE[0]>0.25).

  12. New approaches for improving energy efficiency in the Brazilian industry

    Directory of Open Access Journals (Sweden)

    Paulo Henrique de Mello Santana

    2016-11-01

    Full Text Available The Brazilian government has been promoting energy efficiency measures for industry since the eighties but with very limited returns, as shown in this paper. The governments of some other countries dedicated much more effort and funds for this area and reached excellent results. The institutional arrangements and types of programmes adopted in these countries are briefly evaluated in the paper and provide valuable insights for several proposals put forward here to make more effective the Brazilian government actions directed to overcome market barriers and improve energy efficiency in the local industry. The proposed measures include the creation of Industrial Assessment Centres and an executive agency charged with the coordination of all energy efficiency programmes run by the Federal government. A large share of the Brazilian industry energy consumption comes from energy-intensive industrial branches. According to a recent survey, most of them have substantial energy conservation potentials. To materialize a fair amount of them, voluntary targets concerning energy efficiency gains should start to be negotiated between the Government and associations representing these industrial branches. Credit facilities and tax exemptions for energy-efficient equipment’s should be provided to stimulate the interest of the entrepreneurs and the setting-up of bolder targets.

  13. High Performance Healthcare Buildings: A Roadmap to Improved Energy Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Singer, Brett C.; Tschudi, William F.

    2009-09-08

    This document presents a road map for improving the energy efficiency of hospitals and other healthcare facilities. The report compiles input from a broad array of experts in healthcare facility design and operations. The initial section lists challenges and barriers to efficiency improvements in healthcare. Opportunities are organized around the following ten themes: understanding and benchmarking energy use; best practices and training; codes and standards; improved utilization of existing HVAC designs and technology; innovation in HVAC design and technology; electrical system design; lighting; medical equipment and process loads; economic and organizational issues; and the design of next generation sustainable hospitals. Achieving energy efficiency will require a broad set of activities including research, development, deployment, demonstration, training, etc., organized around 48 specific objectives. Specific activities are prioritized in consideration of potential impact, likelihood of near- or mid-term feasibility and anticipated cost-effectiveness. This document is intended to be broad in consideration though not exhaustive. Opportunities and needs are identified and described with the goal of focusing efforts and resources.

  14. Improving crop nutrient efficiency through root architecture modifications.

    Science.gov (United States)

    Li, Xinxin; Zeng, Rensen; Liao, Hong

    2016-03-01

    Improving crop nutrient efficiency becomes an essential consideration for environmentally friendly and sustainable agriculture. Plant growth and development is dependent on 17 essential nutrient elements, among them, nitrogen (N) and phosphorus (P) are the two most important mineral nutrients. Hence it is not surprising that low N and/or low P availability in soils severely constrains crop growth and productivity, and thereby have become high priority targets for improving nutrient efficiency in crops. Root exploration largely determines the ability of plants to acquire mineral nutrients from soils. Therefore, root architecture, the 3-dimensional configuration of the plant's root system in the soil, is of great importance for improving crop nutrient efficiency. Furthermore, the symbiotic associations between host plants and arbuscular mycorrhiza fungi/rhizobial bacteria, are additional important strategies to enhance nutrient acquisition. In this review, we summarize the recent advances in the current understanding of crop species control of root architecture alterations in response to nutrient availability and root/microbe symbioses, through gene or QTL regulation, which results in enhanced nutrient acquisition. © 2015 Institute of Botany, Chinese Academy of Sciences.

  15. Statistical estimate of mercury removal efficiencies for air pollution control devices of municipal solid waste incinerators.

    Science.gov (United States)

    Takahashi, Fumitake; Kida, Akiko; Shimaoka, Takayuki

    2010-10-15

    Although representative removal efficiencies of gaseous mercury for air pollution control devices (APCDs) are important to prepare more reliable atmospheric emission inventories of mercury, they have been still uncertain because they depend sensitively on many factors like the type of APCDs, gas temperature, and mercury speciation. In this study, representative removal efficiencies of gaseous mercury for several types of APCDs of municipal solid waste incineration (MSWI) were offered using a statistical method. 534 data of mercury removal efficiencies for APCDs used in MSWI were collected. APCDs were categorized as fixed-bed absorber (FA), wet scrubber (WS), electrostatic precipitator (ESP), and fabric filter (FF), and their hybrid systems. Data series of all APCD types had Gaussian log-normality. The average removal efficiency with a 95% confidence interval for each APCD was estimated. The FA, WS, and FF with carbon and/or dry sorbent injection systems had 75% to 82% average removal efficiencies. On the other hand, the ESP with/without dry sorbent injection had lower removal efficiencies of up to 22%. The type of dry sorbent injection in the FF system, dry or semi-dry, did not make more than 1% difference to the removal efficiency. The injection of activated carbon and carbon-containing fly ash in the FF system made less than 3% difference. Estimation errors of removal efficiency were especially high for the ESP. The national average of removal efficiency of APCDs in Japanese MSWI plants was estimated on the basis of incineration capacity. Owing to the replacement of old APCDs for dioxin control, the national average removal efficiency increased from 34.5% in 1991 to 92.5% in 2003. This resulted in an additional reduction of about 0.86Mg emission in 2003. Further study using the methodology in this study to other important emission sources like coal-fired power plants will contribute to better emission inventories. Copyright © 2010 Elsevier B.V. All rights

  16. Highly efficient phosphorescent blue and white organic light-emitting devices with simplified architectures

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Chih-Hao, E-mail: chc@saturn.yzu.edu.tw [Department of Photonics Engineering, Yuan Ze University, Chung-Li, Taiwan 32003 (China); Ding, Yong-Shung; Hsieh, Po-Wei; Chang, Chien-Ping; Lin, Wei-Chieh [Department of Photonics Engineering, Yuan Ze University, Chung-Li, Taiwan 32003 (China); Chang, Hsin-Hua, E-mail: hhua3@mail.vnu.edu.tw [Department of Electro-Optical Engineering, Vanung University, Chung-Li, Taiwan 32061 (China)

    2011-09-01

    Blue phosphorescent organic light-emitting devices (PhOLEDs) with quantum efficiency close to the theoretical maximum were achieved by utilizing a double-layer architecture. Two wide-triplet-gap materials, 1,3-bis(9-carbazolyl)benzene and 1,3,5-tri[(3-pyridyl)-phen-3-yl]benzene, were employed in the emitting and electron-transport layers respectively. The opposite carrier-transport characteristics of these two materials were leveraged to define the exciton formation zone and thus increase the probability of recombination. The efficiency at practical luminance (100 cd/m{sup 2}) was as high as 20.8%, 47.7 cd/A and 31.2 lm/W, respectively. Furthermore, based on the design concept of this simplified architecture, efficient warmish-white PhOLEDs were developed. Such two-component white organic light-emitting devices exhibited rather stable colors over a wide brightness range and yielded electroluminescence efficiencies of 15.3%, 33.3 cd/A, and 22.7 lm/W in the forward directions.

  17. Highly efficient phosphorescent blue and white organic light-emitting devices with simplified architectures

    International Nuclear Information System (INIS)

    Chang, Chih-Hao; Ding, Yong-Shung; Hsieh, Po-Wei; Chang, Chien-Ping; Lin, Wei-Chieh; Chang, Hsin-Hua

    2011-01-01

    Blue phosphorescent organic light-emitting devices (PhOLEDs) with quantum efficiency close to the theoretical maximum were achieved by utilizing a double-layer architecture. Two wide-triplet-gap materials, 1,3-bis(9-carbazolyl)benzene and 1,3,5-tri[(3-pyridyl)-phen-3-yl]benzene, were employed in the emitting and electron-transport layers respectively. The opposite carrier-transport characteristics of these two materials were leveraged to define the exciton formation zone and thus increase the probability of recombination. The efficiency at practical luminance (100 cd/m 2 ) was as high as 20.8%, 47.7 cd/A and 31.2 lm/W, respectively. Furthermore, based on the design concept of this simplified architecture, efficient warmish-white PhOLEDs were developed. Such two-component white organic light-emitting devices exhibited rather stable colors over a wide brightness range and yielded electroluminescence efficiencies of 15.3%, 33.3 cd/A, and 22.7 lm/W in the forward directions.

  18. Efficient non-doped phosphorescent orange, blue and white organic light-emitting devices

    Science.gov (United States)

    Yin, Yongming; Yu, Jing; Cao, Hongtao; Zhang, Letian; Sun, Haizhu; Xie, Wenfa

    2014-10-01

    Efficient phosphorescent orange, blue and white organic light-emitting devices (OLEDs) with non-doped emissive layers were successfully fabricated. Conventional blue phosphorescent emitters bis [4,6-di-fluorophenyl]-pyridinato-N,C2'] picolinate (Firpic) and Bis(2,4-difluorophenylpyridinato) (Fir6) were adopted to fabricate non-doped blue OLEDs, which exhibited maximum current efficiency of 7.6 and 4.6 cd/A for Firpic and Fir6 based devices, respectively. Non-doped orange OLED was fabricated utilizing the newly reported phosphorescent material iridium (III) (pbi)2Ir(biq), of which manifested maximum current and power efficiency of 8.2 cd/A and 7.8 lm/W. The non-doped white OLEDs were achieved by simply combining Firpic or Fir6 with a 2-nm (pbi)2Ir(biq). The maximum current and power efficiency of the Firpic and (pbi)2Ir(biq) based white OLED were 14.8 cd/A and 17.9 lm/W.

  19. System Efficiency Improvement for Electric Vehicles Adopting a Permanent Magnet Synchronous Motor Direct Drive System

    Directory of Open Access Journals (Sweden)

    Chengming Zhang

    2017-12-01

    Full Text Available To improve the endurance mileage of electric vehicles (EVs, it is important to decrease the energy consumption of the Permanent Magnet Synchronous Motor (PMSM drive system. This paper proposes a novel loss optimization control strategy named system efficiency improvement control which can optimize both inverter and motor losses. A nonlinear power converter loss model is built to fit the nonlinear characteristics of power devices. This paper uses double Fourier integral analysis to analytically calculate the fundamental and harmonic components of motor current by which the fundamental motor loss and harmonic motor loss can be accurately analyzed. From these loss models, a whole-frequency-domain system loss model is derived and presented. Based on the system loss model, the system efficiency improvement control method applies the genetic algorithm to adjust the motor current and PWM frequency together to optimize the inverter and motor losses by which the system efficiency can be significantly improved without seriously influence on the system stability over the whole operation range of EVs. The optimal effects of system efficiency is verified by the experimental results in both Si-IGBT-based PMSM system and SiC-MOSFET-based system.

  20. SU-F-T-163: Improve Proton Therapy Efficiency: Report of a Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Y [Procure Proton Therapy Center, Oklahoma City, OK (United States); Flanz, J [Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Mah, D [Procure Treatment Center, Somerset, NJ (United States); Pankuch, M; Kreydick, B [Northwestern Medicine Proton Center, Warrenville, IL (United States); Beltran, C [Mayo Clinic, Rochester, MN (United States); Robison, B; Schreuder, A [Provision Healthcare Partners, Knoxville, TN (United States)

    2016-06-15

    Purpose: The technology of proton therapy, especially the pencil beam scanning technique, is evolving very quickly. However, the efficiency of proton therapy seems to lag behind conventional photon therapy. The purpose of the abstract is to report on the findings of a workshop on improvement of QA, planning and treatment efficiency in proton therapy. Methods: A panel of physicists, clinicians, and vendor representatives from over 18 institutions in the United States and internationally were convened in Knoxville, Tennessee in November, 2015. The panel discussed several topics on how to improve proton therapy efficiency, including 1) lean principle and failure mode and effects analysis, 2) commissioning and machine QA, 3) treatment planning, optimization and evaluation, 4) patient positioning and IGRT, 5) vendor liaison and machine availability, and 6) staffing, education and training. Results: The relative time needed for machine QA, treatment planning & check in proton therapy was found to range from 1 to 2.5 times of that in photon therapy. Current status in proton QA, planning and treatment was assessed. Key areas for efficiency improvement, such as elimination of unnecessary QA items or steps and development of efficient software or hardware tools, were identified. A white paper to summarize our findings is being written. Conclusion: It is critical to improve efficiency by developing reliable proton beam lines, efficient software tools on treatment planning, optimization and evaluation, and dedicated proton QA device. Conscious efforts and collaborations from both industry leaders and proton therapy centers are needed to achieve this goal and further advance the technology of proton therapy.

  1. Improving the efficiency of photovoltaic (PV) panels by oil coating

    International Nuclear Information System (INIS)

    Abd-Elhady, M.S.; Fouad, M.M.; Khalil, T.

    2016-01-01

    Highlights: • It is possible to improve the efficiency of PV panels by increasing the amount of light transmitted to the panel. • Coating PV panels by a fine layer of Labovac oil increases the amount of sun light transmitted to the panel. • Coating PV panels by a fine layer of Labovac oil increases the power output of the panel. • Coating PV panels with a layer of Labovac oil has to be applied in cold countries and not in hot regions. - Abstract: The objective of this research is to develop a new technique for improving the efficiency of Photovoltaic (PV) panels. This technique is done by coating the front surface of the PV panel by a fine layer of oil in order to increase the amount of light transmitted to the panel, and consequently its efficiency. Different types of oils are examined, including both mineral oils and natural oils. In case of mineral oils; vacuum pump oil (Labovac oil), engine oil (Mobil oil) and brake oil (Abro oil) are examined, while in case of natural oils; olive and sunflower oils are examined. An experimental setup has been developed to examine the performance of the PV panels as a function of oil coatings. The experimental setup consists of an artificial sun, the PV panel under investigation, a cooling system and a measuring system to measure the performance of the panel. It has been found that coating the PV panel with a fine layer of Labovac oil, ∼1 mm thick, improves the efficiency of the PV panel by more than 20%, and this is due to the high transmissivity of the Labovac oil compared to other oils. However, the Labovac oil has a drawback which is overheating of the panel due to its high transmissivity. Coating of PV panels with a fine layer of Labovac oil should be done only in cold regions, in order to avoid the heating effect that can decrease the power output of PV panels.

  2. Irradiation damages of semiconductor devices and their improvement

    Energy Technology Data Exchange (ETDEWEB)

    Uwatoko, Yoshiya [Saitama Univ., Urawa (Japan); Ohyama, Hidenori; Hayama, Kiyoteru; Hakata, Tetsuya; Kudou, Tomohiro

    1998-01-01

    In this study, effect of radiation on semiconductor devices was evaluated at both sides of electrical and crystalline properties for two years from 1995 fiscal years. And, damage of Si(sub 1-x)Ge(sub x) device was considered at viewpoints of Ge content and sprung-out atomic number and non ionization energy loss of constituting atom formed by radiation on its radiation source dependency of damage. This paper was a report on proton beam damage of the Si(sub 1-x)Ge(sub x) device, neutron damage of InGaAs photodiode, and effect of Ga content and kinds of beam on their damages. (G.K.)

  3. High-efficiency white organic light-emitting devices with a non-doped yellow phosphorescent emissive layer

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Juan; Yu Junsheng, E-mail: jsyu@uestc.edu.cn; Hu Xiao; Hou Menghan; Jiang Yadong

    2012-03-30

    Highly efficient phosphorescent white organic light-emitting devices (PHWOLEDs) with a simple structure of ITO/TAPC (40 nm)/mCP:FIrpic (20 nm, x wt.%)/bis[2-(4-tertbutylphenyl)benzothiazolato-N,C{sup 2} Prime ] iridium (acetylacetonate) (tbt){sub 2}Ir(acac) (y nm)/Bphen (30 nm)/Mg:Ag (200 nm) have been developed, by inserting a thin layer of non-doped yellow phosphorescent (tbt){sub 2}Ir(acac) between doped blue emitting layer (EML) and electron transporting layer. By changing the doping concentration of the blue EML and the thickness of the non-doped yellow EML, a PHWOLED comprised of higher blue doping concentration and thinner yellow EML achieves a high current efficiency of 31.7 cd/A and Commission Internationale de l'Eclairage coordinates of (0.33, 0.41) at a luminance of 3000 cd/m{sup 2} could be observed. - Highlights: Black-Right-Pointing-Pointer We introduce a simplified architecture for phosphorescent white organic light-emitting device. Black-Right-Pointing-Pointer The key concept of device fabrication is combination of doped blue emissive layer (EML) with non-doped ultra-thin yellow EML. Black-Right-Pointing-Pointer Doping concentration of the blue EML and thickness of the yellow EML are sequentially adjusted. Black-Right-Pointing-Pointer High device performance is achieved due to improved charge carrier balance as well as two parallel emission mechanisms in the EMLs.

  4. Improvement of Engineering Work Efficiency through System Integration

    International Nuclear Information System (INIS)

    Lee, Sangdae; Jo, Sunghan; Hyun, Jinwoo

    2016-01-01

    This paper presents the concept of developing an integrated engineering system for ER to improve efficiency and utilization of engineering system. Each process including computer system and database was introduced separately by each department at that different time. Each engineering process has a close relation with other engineering processes. The introduction of processes in a different time has caused the several problems such as lack of interrelationship between engineering processes, lack of integration fleet-wide statistical data, lack of the function of data comparison among plants and increase of access time by different access location on internet. These problems have caused inefficiency of engineering system utilization to get proper information and degraded engineering system utilization. KHNP has introduced and conducted advanced engineering processes to maintain equipment effectively in a highly reliable condition since 2000s. But engineering systems for process implementation have been developed in each department at a different time. This has caused the problems of process inefficiency and data discordance. Integrated Engineering System(IES) to integrate dispersed engineering processes will improve work efficiency and utilization of engineering system because integration system would enable engineer to get total engineering information easily and do engineering work efficiently

  5. Improvement of Engineering Work Efficiency through System Integration

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sangdae; Jo, Sunghan; Hyun, Jinwoo [KHNP CRI, Daejeon (Korea, Republic of)

    2016-10-15

    This paper presents the concept of developing an integrated engineering system for ER to improve efficiency and utilization of engineering system. Each process including computer system and database was introduced separately by each department at that different time. Each engineering process has a close relation with other engineering processes. The introduction of processes in a different time has caused the several problems such as lack of interrelationship between engineering processes, lack of integration fleet-wide statistical data, lack of the function of data comparison among plants and increase of access time by different access location on internet. These problems have caused inefficiency of engineering system utilization to get proper information and degraded engineering system utilization. KHNP has introduced and conducted advanced engineering processes to maintain equipment effectively in a highly reliable condition since 2000s. But engineering systems for process implementation have been developed in each department at a different time. This has caused the problems of process inefficiency and data discordance. Integrated Engineering System(IES) to integrate dispersed engineering processes will improve work efficiency and utilization of engineering system because integration system would enable engineer to get total engineering information easily and do engineering work efficiently.

  6. Policy modeling for energy efficiency improvement in US industry

    International Nuclear Information System (INIS)

    Worrell, Ernst; Price, Lynn; Ruth, Michael

    2001-01-01

    We are at the beginning of a process of evaluating and modeling the contribution of policies to improve energy efficiency. Three recent policy studies trying to assess the impact of energy efficiency policies in the United States are reviewed. The studies represent an important step in the analysis of climate change mitigation strategies. All studies model the estimated policy impact, rather than the policy itself. Often the policy impacts are based on assumptions, as the effects of a policy are not certain. Most models only incorporate economic (or price) tools, which recent studies have proven to be insufficient to estimate the impacts, costs and benefits of mitigation strategies. The reviewed studies are a first effort to capture the effects of non-price policies. The studies contribute to a better understanding of the role of policies in improving energy efficiency and mitigating climate change. All policy scenarios results in substantial energy savings compared to the baseline scenario used, as well as substantial net benefits to the U.S. economy

  7. Modified paraffin wax for improvement of histological analysis efficiency.

    Science.gov (United States)

    Lim, Jin Ik; Lim, Kook-Jin; Choi, Jin-Young; Lee, Yong-Keun

    2010-08-01

    Paraffin wax is usually used as an embedding medium for histological analysis of natural tissue. However, it is not easy to obtain enough numbers of satisfactory sectioned slices because of the difference in mechanical properties between the paraffin and embedded tissue. We describe a modified paraffin wax that can improve the histological analysis efficiency of natural tissue, composed of paraffin and ethylene vinyl acetate (EVA) resin (0, 3, 5, and 10 wt %). Softening temperature of the paraffin/EVA media was similar to that of paraffin (50-60 degrees C). The paraffin/EVA media dissolved completely in xylene after 30 min at 50 degrees C. Physical properties such as the amount of load under the same compressive displacement, elastic recovery, and crystal intensity increased with increased EVA content. EVA medium (5 wt %) was regarded as an optimal composition, based on the sectioning efficiency measured by the numbers of unimpaired sectioned slices, amount of load under the same compressive displacement, and elastic recovery test. Based on the staining test of sectioned slices embedded in a 5 wt % EVA medium by hematoxylin and eosin (H&E), Masson trichrome (MT), and other staining tests, it was concluded that the modified paraffin wax can improve the histological analysis efficiency with various natural tissues. (c) 2010 Wiley-Liss, Inc.

  8. Improving efficiency and effectiveness in natural gas regulation : discussion paper

    International Nuclear Information System (INIS)

    Rounding, M.C.

    2004-11-01

    Energy market liberalization is a world trend that has prompted the deregulation of natural gas and electricity over the past twenty years in North America. The Ontario Energy Board and the National Energy Board are conducting public hearings on natural gas regulation in response to the request by Canadian energy industries for better regulatory streamlining. The following 5 issues regarding natural gas regulation in Canada have been examined: (1) system gas in a regulated market, (2) natural gas infrastructure investments and capital renewal, (3) improving efficiency in gas regulation, (4) expectations of performance-based regulation (PBR) in the natural gas industry, and (5) the debate whether further deregulation of the natural gas industry is beneficial. This paper discusses the impact that natural gas regulation has had on the efficiency and competitiveness of the industry and its affect on customers and other stakeholders. It focuses on the efficiency of the regulatory process and examines regulatory objectives, best practices and performance indicators. The factors that determine the efficiency of natural gas regulation include alternative regulatory models, structure of the regulatory agency, regulatory framework approaches, and outcomes for the natural gas industry. The relationship between the government and the regulator was also examined in terms of their abilities to implement policy. A comparative evaluation between energy regulators in Canada, the United States, Australia and the United Kingdom was presented. The balancing of short-term and long-term objectives for gas supply and planning issues was also addressed. 17 refs

  9. Bait station devices can improve mass trapping performance for the control of the Mediterranean fruit fly

    OpenAIRE

    Navarro-Llopis, Vicente; Primo Millo, Jaime; Vacas González, Sandra

    2015-01-01

    BACKGROUNDThe use of traps and other attract-and-kill devices in pest management strategies to reduce Mediterranean fruit fly populations has proved to be efficient. Nevertheless, many farmers are concerned about the effect of these devices on the trees where they are hung. Direct field observations have revealed that fruit damage is higher in trees with traps than in trees without them. This work evaluates the efficacy of different types of attract-and-kill device to protect fruit of the sin...

  10. Reliability improvement in GaN HEMT power device using a field plate approach

    Science.gov (United States)

    Wu, Wen-Hao; Lin, Yueh-Chin; Chin, Ping-Chieh; Hsu, Chia-Chieh; Lee, Jin-Hwa; Liu, Shih-Chien; Maa, Jer-shen; Iwai, Hiroshi; Chang, Edward Yi; Hsu, Heng-Tung

    2017-07-01

    This study investigates the effect of implementing a field plate on a GaN high-electron-mobility transistor (HEMT) to improve power device reliability. The results indicate that the field plate structure reduces the peak electrical field and interface traps in the device, resulting in higher breakdown voltage, lower leakage current, smaller current collapse, and better threshold voltage control. Furthermore, after high voltage stress, steady dynamic on-resistance and gate capacitance degradation improvement were observed for the device with the field plate. This demonstrates that GaN device reliability can be improved by using the field plate approach.

  11. High resolution PET breast imager with improved detection efficiency

    Science.gov (United States)

    Majewski, Stanislaw

    2010-06-08

    A highly efficient PET breast imager for detecting lesions in the entire breast including those located close to the patient's chest wall. The breast imager includes a ring of imaging modules surrounding the imaged breast. Each imaging module includes a slant imaging light guide inserted between a gamma radiation sensor and a photodetector. The slant light guide permits the gamma radiation sensors to be placed in close proximity to the skin of the chest wall thereby extending the sensitive region of the imager to the base of the breast. Several types of photodetectors are proposed for use in the detector modules, with compact silicon photomultipliers as the preferred choice, due to its high compactness. The geometry of the detector heads and the arrangement of the detector ring significantly reduce dead regions thereby improving detection efficiency for lesions located close to the chest wall.

  12. Evaluation and Improvement of Lighting Efficiency in Working Spaces

    Directory of Open Access Journals (Sweden)

    Ana Castillo-Martinez

    2018-04-01

    Full Text Available Lighting is an essential element for modern life, promoting a sense of wellbeing for users. However, bad illumination may produce health problems such as headaches and fatigue, among other vision problems. For that reason, this paper proposes the development of a smartphone-based application to help in lighting evaluation to guarantee the compliance of illumination regulations and to help increase illuminance efficiency, reducing its energy consumption. To perform this evaluation, the smartphone can be used as a lighting measurement tool, evaluating those measurements through an intelligent agent based in rules capable of guiding the decision-making process. As a result, this tool allows the evaluation of the real working environment to guarantee lighting requirements, helping in the prevention of health problems derived from bad illumination and improving the lighting efficiency at the same time.

  13. Improving broadcast performance of radio duty-cycled Internet-of-Things devices

    NARCIS (Netherlands)

    Guclu, S.S.; Özcelebi, T.; Lukkien, J.J.

    2017-01-01

    Asynchronous Radio Duty Cycling (ARDC) protocols can make embedded networked devices more energy efficient by keeping their radio off most of the time without a need for synchronization between devices. Some ARDC protocols can operate under 6LoWPAN adaptation layer in order to enable the vision of

  14. Highly efficient quantum dot-based photoconductive THz materials and devices

    Science.gov (United States)

    Rafailov, E. U.; Leyman, R.; Carnegie, D.; Bazieva, N.

    2013-09-01

    We demonstrate Terahertz (THz) signal sources based on photoconductive (PC) antenna devices comprising active layers of InAs semiconductor quantum dots (QDs) on GaAs. Antenna structures comprised of multiple active layers of InAs:GaAs PC materials are optically pumped using ultrashort pulses generated by a Ti:Sapphire laser and CW dualwavelength laser diodes. We also characterised THz output signals using a two-antenna coherent detection system. We discuss preliminary performance data from such InAs:GaAs THz devices which exhibit efficient emission of both pulsed and continuous wave (CW) THz signals and significant optical-to-THz conversion at both absorption wavelength ranges, <=850 nm and <=1300 nm.

  15. Energy efficiency improvement and cost saving opportunities forpetroleum refineries

    Energy Technology Data Exchange (ETDEWEB)

    Worrell, Ernst; Galitsky, Christina

    2005-02-15

    The petroleum refining industry in the United States is the largest in the world, providing inputs to virtually any economic sector,including the transport sector and the chemical industry. The industry operates 146 refineries (as of January 2004) around the country,employing over 65,000 employees. The refining industry produces a mix of products with a total value exceeding $151 billion. Refineries spend typically 50 percent of cash operating costs (i.e., excluding capital costs and depreciation) on energy, making energy a major cost factor and also an important opportunity for cost reduction. Energy use is also a major source of emissions in the refinery industry making energy efficiency improvement an attractive opportunity to reduce emissions and operating costs. Voluntary government programs aim to assist industry to improve competitiveness through increased energy efficiency and reduced environmental impact. ENERGY STAR (R), a voluntary program managed by the U.S. Environmental Protection Agency, stresses the need for strong and strategic corporate energy management programs. ENERGY STAR provides energy management tools and strategies for successful corporate energy management programs. This Energy Guide describes research conducted to support ENERGY STAR and its work with the petroleum refining industry.This research provides information on potential energy efficiency opportunities for petroleum refineries. This Energy Guide introduces energy efficiency opportunities available for petroleum refineries. It begins with descriptions of the trends, structure, and production of the refining industry and the energy used in the refining and conversion processes. Specific energy savings for each energy efficiency measure based on case studies of plants and references to technical literature are provided. If available, typical payback periods are also listed. The Energy Guide draws upon the experiences with energy efficiency measures of petroleum refineries worldwide

  16. Improving crop water use efficiency using carbon isotope discrimination

    International Nuclear Information System (INIS)

    Serraj, R.

    2006-01-01

    Water scarcity, drought and salinity are among the most important environmental constraints challenging crop productivity in the arid and semi-arid regions of the world, especially the rain-fed production systems. The current challenge is to enhance food security in water-limited and/or salt-affected areas for the benefit of resource-poor farmers in developing countries. There is also an increasing need that water use in agriculture should focus on improvement in the management of existing water resources and enhancing crop water productivity. The method based on carbon-13 discrimination in plant tissues has a potentially important role in the selection and breeding of some crop species for increased water use efficiency in some specific environments. Under various water-limited environments, low delta in the plants, indicating low carbon isotope discrimination has been generally associated with high transpiration efficiency (TE). In contrast, for well-watered environments many positive genotypic correlations have been reported between delta and grain yield indicating potential value in selecting for greater delta in these environments. Few studies have been reported on the impact of selection for delta on adaptation and grain yield in saline environments. Studies of the impact of genetic selection for greater and lower delta are currently coordinated by the Soil and water Management and Crop Nutrition Section (SWMCN) of the Joint FAO/IAEA Division. A Coordinated Research Project (CRP) is currently on-going on the Selection for Greater Agronomic Water-Use Efficiency in Wheat and Rice using Carbon Isotope Discrimination (D1-20 08). The overall objective of this project is to contribute to increasing the agronomic water-use efficiency of wheat and rice production, where agronomic water-use efficiency is defined as grain yield/total water use including both transpiration and evaporation. The CRP is also aiming at increasing wheat productivity under drought and rice

  17. Improving the global efficiency in small hydropower practice

    Science.gov (United States)

    Razurel, P.; Gorla, L.; Crouzy, B.; Perona, P.

    2015-12-01

    The global increase in energy production from renewable sources has seen river exploitation for small hydropower plants to also grow considerably in the last decade. River intakes used to divert water from the main course to the power plant are at the base of such practice. A key issue concern with finding innovative concepts to both design and manage such structures in order to improve classic operational rules. Among these, the Minimal Flow Release (MFR) concept has long been used in spite of its environmental inconsistency.In this work, we show that the economical and ecological efficiency of diverting water for energy production in small hydropower plants can be improved towards sustainability by engineering a novel class of flow-redistribution policies. We use the mathematical form of the Fermi-Dirac statistical distribution to define non-proportional dynamic flow-redistribution rules, which broadens the spectrum of dynamic flow releases based on proportional redistribution. The theoretical background as well as the economic interpretation is presented and applied to three case studies in order to systematically test the global performance of such policies. Out of numerical simulations, a Pareto frontier emerges in the economic vs environmental efficiency plot, which show that non-proportional distribution policies improve both efficiencies with respect to those obtained from some traditional MFR and proportional policies. This picture is shown also for long term climatic scenarios affecting water availability and the natural flow regime.In a time of intense and increasing exploitation close to resource saturation, preserving natural river reaches requires to abandon inappropriate static release policies in favor of non-proportional ones towards a sustainable use of the water resource.

  18. Thermal analysis and improvement of cascode GaN device package for totem-pole bridgeless PFC rectifier

    International Nuclear Information System (INIS)

    She, Shuojie; Zhang, Wenli; Liu, Zhengyang; Lee, Fred C.; Huang, Xiucheng; Du, Weijing; Li, Qiang

    2015-01-01

    The totem-pole bridgeless power factor correction (PFC) rectifier has a simpler topology and higher efficiency than other boost-type bridgeless PFC rectifiers. Its promising performance is enabled by using high-voltage gallium nitride (GaN) high-electron-mobility transistors, which have considerably better figures of merit (e.g., lower reverse recovery charges and less switching losses) than the state-of-the-art silicon metal-oxide-semiconductor field-effect transistors. Cascode GaN devices in traditional packages, i.e., the TO-220 and power quad flat no-lead, are used in the totem-pole PFC boost rectifier. But the parasitic inductances induced by the traditional packages not only significantly deteriorate the switching characteristics of the discrete GaN device but also adversely affect the performance of the built PFC rectifier. A new stack-die packaging structure with an embedded capacitor has been introduced and proven to be efficient in reducing parasitic ringing at the turn-off transition and achieving true zero-voltage-switching turn-on. However, the thermal dissipation capability of the device packaged in this configuration becomes a limitation on further pushing the operating frequency and the output current level for high-efficiency power conversion. This paper focuses on the thermal analysis of the cascode GaN devices in different packages and the GaN-based multichip module used in a two-phase totem-pole bridgeless PFC boost rectifier. A series of thermal models are built based on the actual structures and materials of the packaged devices to evaluate their thermal performance. Finite element analysis (FEA) simulation results of the cascode GaN device in a flip-chip format demonstrate the possibility of increasing the device switching speed while maintaining the peak temperature of the device below 125 °C. Thermal analysis of the GaN-based power module in a very similar structure is also conducted using the FEA method. Experimental data measured using

  19. LSB steganography with improved embedding efficiency and undetectability

    OpenAIRE

    Khalind, Omed; Aziz, Benjamin Yowell Yousif

    2015-01-01

    In this paper, we propose a new method of non-adapt ive LSB steganography in still images to improve the embedding efficiency from 2 to 8/3 rand om bits per one embedding change even for the embedding rate of 1 bit per pixel. The method t akes 2-bits of the secret message at a time and compares them to the LSBs of the two chosen pix el values for embedding, it always assumes a single mismatch between the two and uses the seco nd LSB o...

  20. The technological raw material heating furnaces operation efficiency improving issue

    Science.gov (United States)

    Paramonov, A. M.

    2017-08-01

    The issue of fuel oil applying efficiency improving in the technological raw material heating furnaces by means of its combustion intensification is considered in the paper. The technical and economic optimization problem of the fuel oil heating before combustion is solved. The fuel oil heating optimal temperature defining method and algorithm analytically considering the correlation of thermal, operating parameters and discounted costs for the heating furnace were developed. The obtained optimization functionality provides the heating furnace appropriate thermal indices achievement at minimum discounted costs. The carried out research results prove the expediency of the proposed solutions using.

  1. Improving the Efficiency of Photon Collection by Compton Rescue

    Science.gov (United States)

    2011-03-01

    burnished by vibratory shot peening,” Acta Physica Polonica , vol. A 110, pp. 739–46, 2006. [4] M. Cunningham et al., “First-generation hybrid compact...Department of Defense, or the United States Government. This material is declared a work of the U.S. Government and is not subject to copyright...R. Kowash (Member) Date AFIT/GAP/ENP/11-M10 Abstract A method to improve the efficiency of photon collection in thin planar HPGe de- tectors was

  2. Improving the Efficient of Ernie Turner Center. Final Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    Fredeen, Amy

    2011-03-21

    The objective of this project was to complete the specifications and drawings for a variable speed kitchen exhaust system and the boiler heating system which when implemented will improve the heating efficiency of the building. The design work was focused in two key areas: kitchen ventilation and heating for the Ernie Turner Center building (ETC). RSA completed design work and issued a set of 100% drawings. RSA also worked with a cost estimator to put together a detailed cost estimate for the project. The design components are summarized.

  3. Fast reactor core concepts to improve transmutation efficiency

    International Nuclear Information System (INIS)

    Fujimura, Koji; Kawashima, Katsuyuki; Itooka, Satoshi

    2015-01-01

    Fast Reactor (FR) core concepts to improve transmutation efficiency were conducted. A heterogeneous MA loaded core was designed based on the 1000MWe-ABR breakeven core. The heterogeneous MA loaded core with Zr-H loaded moderated targets had a better transmutation performance than the MA homogeneous loaded core. The annular pellet rod design was proposed as one of the possible design options for the MA target. It was shown that using annular pellet MA rods mitigates the self-shielding effect in the moderated target so as to enhance the transmutation rate

  4. Improving the Performance of Semiconductor Sensor Devices Using Surface Functionalization

    Science.gov (United States)

    Rohrbaugh, Nathaniel W.

    As production and understanding of III-nitride growth has progressed, this class of material has been used for its semiconducting properties in the fields of computer processing, microelectronics, and LEDs. As understanding of materials properties has advanced, devices were fabricated to be sensitive to environmental surroundings such as pH, gas, or ionic concentration. Simultaneously the world of pharmaceuticals and environmental science has come to the age where the use of wearable devices and active environmental sensing can not only help us learn more about our surroundings, but help save lives. At the crossroads of these two fields work has been done in marrying the high stability and electrical properties of the III-nitrides with the needs of a growing sensor field for various environments and stimuli. Device architecture can only get one so far, and thus the need for well understood surface functionalization techniques has arisen in the field of III-nitride environmental sensing. Many existing schemes for functionalization involve chemistries that may be unfriendly to a biological environment, unstable in solution, or expensive to produce. One possible solution to these issues is the work presented here, which highlights a surface modification scheme utilizing phosphonic acid based chemistry and biomolecular attachment. This dissertation presents a set of studies and experiments quantifying and analyzing the response behaviors of AlGaN/GaN field effect transistor (FET) devices via their interfacial electronic properties. Additional investigation was done on the modification of these surfaces, effects of stressful environmental conditions, and the utility of the phosphonic acid surface treatments. Signals of AlGaN/GaN FETs were measured as IDrain values and in the earliest study an average signal increase of 96.43% was observed when surfaces were incubated in a solution of a known recognition peptide sequence (SVSVGMKPSPRP). This work showed that even without

  5. A Polynomial Subset-Based Efficient Multi-Party Key Management System for Lightweight Device Networks.

    Science.gov (United States)

    Mahmood, Zahid; Ning, Huansheng; Ghafoor, AtaUllah

    2017-03-24

    Wireless Sensor Networks (WSNs) consist of lightweight devices to measure sensitive data that are highly vulnerable to security attacks due to their constrained resources. In a similar manner, the internet-based lightweight devices used in the Internet of Things (IoT) are facing severe security and privacy issues because of the direct accessibility of devices due to their connection to the internet. Complex and resource-intensive security schemes are infeasible and reduce the network lifetime. In this regard, we have explored the polynomial distribution-based key establishment schemes and identified an issue that the resultant polynomial value is either storage intensive or infeasible when large values are multiplied. It becomes more costly when these polynomials are regenerated dynamically after each node join or leave operation and whenever key is refreshed. To reduce the computation, we have proposed an Efficient Key Management (EKM) scheme for multiparty communication-based scenarios. The proposed session key management protocol is established by applying a symmetric polynomial for group members, and the group head acts as a responsible node. The polynomial generation method uses security credentials and secure hash function. Symmetric cryptographic parameters are efficient in computation, communication, and the storage required. The security justification of the proposed scheme has been completed by using Rubin logic, which guarantees that the protocol attains mutual validation and session key agreement property strongly among the participating entities. Simulation scenarios are performed using NS 2.35 to validate the results for storage, communication, latency, energy, and polynomial calculation costs during authentication, session key generation, node migration, secure joining, and leaving phases. EKM is efficient regarding storage, computation, and communication overhead and can protect WSN-based IoT infrastructure.

  6. Method for making an improved magnetic encoding device

    Science.gov (United States)

    Fox, Richard J.

    1981-01-01

    A magnetic encoding device and method for making the same are provided for use as magnetic storage mediums in identification control applications which give output signals from a reader that are of shorter duration and substantially greater magnitude than those of the prior art. Magnetic encoding elements are produced by uniformly bending wire or strip stock of a magnetic material longitudinally about a common radius to exceed the elastic limit of the material and subsequently mounting the material so that it is restrained in an unbent position on a substrate of nonmagnetic material. The elements are spot weld attached to a substrate to form a binary coded array of elements according to a desired binary code. The coded substrate may be enclosed in a plastic laminate structure. Such devices may be used for security badges, key cards, and the like and may have many other applications.

  7. Improved Usability of Locomotion Devices Using Human-Centric Taxonomy

    Science.gov (United States)

    2009-03-01

    the classification of interaction devices by the limbs used in the interaction rather than by arbitrary classifications, such as “ wand ”, or “glove...ABILITY REQUIREMENTS ANALYSIS USING F-JAS In Tables 5 through 8, we took the results of a sample HAR analysis done by Cockayne and Darken [13] comparing...point less than natural locomotion in all categories except for explosive strength, in which it receives 2 less points. 2. Decelerate from Walk or Jog

  8. Remarkably High Conversion Efficiency of Inverted Bulk Heterojunction Solar Cells: From Ultrafast Laser Spectroscopy and Electron Microscopy to Device Fabrication and Optimization

    KAUST Repository

    Alsulami, Qana

    2016-04-10

    In organic donor-acceptor systems, ultrafast interfacial charge transfer (CT), charge separation (CS), and charge recombination (CR) are key determinants of the overall performance of photovoltaic devices. However, a profound understanding of these photophysical processes at device interfaces remains superficial, creating a major bottleneck that circumvents advancements and the optimization of these solar cells. Here, results from time-resolved laser spectroscopy and high-resolution electron microscopy are examined to provide the fundamental information necessary to fabricate and optimize organic solar cell devices. In real time, CT and CS are monitored at the interface between three fullerene acceptors (FAs) (PC71BM, PC61BM, and IC60BA) and the PTB7-Th donor polymer. Femtosecond transient absorption (fs-TA) data demonstrates that photoinduced electron transfer from the PTB7-Th polymer to each FA occurs on the sub-picosecond time scale, leading to the formation of long-lived radical ions. It is also found that the power conversion efficiency improves from 2% in IC60BA-based solar cells to >9% in PC71BM-based devices, in support of our time-resolved results. The insights reported in this manuscript provide a clear understanding of the key variables involved at the device interface, paving the way for the exploitation of efficient CS and subsequently improving the photoconversion efficiency. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. An Analysis of Sources of Technological Change in Efficiency Improvement of Fluorescent Lamp Systems

    Science.gov (United States)

    Imanaka, Takeo

    In Japan, energy efficient fluorescent lamp systems which use “rare-earth phosphors” and “electronic ballasts” have shown rapid diffusion since 1990s. This report investigated sources of technological change in the efficiency improvement of fluorescent lamp systems: (i) Fluorescent lamp and luminaires have been under steady technological development for getting more energy efficient lighting and the concepts to achieve high efficiency had been found in such activities; however, it took long time until they realized and become widely used; (ii) Electronic ballasts and rare-earth phosphors add fluorescent lamp systems not only energy efficiency but also various values such as compactness, lightweight, higher output, and better color rendering properties, which have also been expected and have induced research and development (R&D) (iii) Affordable electronic ballasts are realized by the new technology “power MOSFET” which is based on IC technologies and has been developed for large markets of information and communication technologies and mobile devices; and (iv) Rare-earth phosphors became available after rare-earth industries developed for the purpose of supplying rare-earth phosphors for color television. In terms of sources of technological change, (i) corresponds to “R&D” aiming at the particular purpose i.e. energy efficiency in this case, on the other hand, (ii), (iii), and (iv) correspond to “spillovers” from activities aiming at other purposes. This case exhibits an actual example in which “spillovers” were the critical sources of technological change in energy technology.

  10. MobileFaceNets: Efficient CNNs for Accurate Real-time Face Verification on Mobile Devices

    OpenAIRE

    Chen, Sheng; Liu, Yang; Gao, Xiang; Han, Zhen

    2018-01-01

    In this paper, we proposed a class of extremely efficient CNN models, MobileFaceNets, which use less than 1 million parameters and are specifically tailored for high-accuracy real-time face verification on mobile and embedded devices. We first make a simple analysis on the weakness of common mobile networks for face verification. The weakness has been well overcome by our specifically designed MobileFaceNets. Under the same experimental conditions, our MobileFaceNets achieve significantly sup...

  11. Efficiency improvement for a sustainable agriculture : the integration of agronomic and farm economics approaches

    NARCIS (Netherlands)

    Koeijer, de T.J.

    2002-01-01

    Keywords: Sustainable farming systems, Agronomic efficiency, Economic efficiency, Environmental efficiency, Sustainability index, Interdisciplinary analysis.

    The objective of the research described in this thesis was to determine what role improved agronomic efficiency can play in

  12. Indoor climate quality after renovation for improved energy efficiency

    DEFF Research Database (Denmark)

    Gunnarsen, Lars Bo; Løck, Sebastian; Kolarik, Barbara

    2016-01-01

    The building sector is responsible for approximately 40 % of the Danish energy consumption. As every year less than 1 % of the building stock is rebuild after demolition of old buildings, improved energy efficiency of existing buildings are in focus. In the late seventies to mid-eighties unwise...... performance. The indoor quality classifications show minor improvements. By using design tools beyond the simple legal requirements, the rental dwelling marked is a far step ahead of most retrofitting of owner-occupied dwellings and houses. The fear of indoor climate degradation from retrofitted energy saving...... measures may be countered by the use of modern design tools and attention to inner moisture membranes and needs for renovation of ventilation systems....

  13. Efficiency improvements in pipeline transportation systems. Technical report, Task 3

    Energy Technology Data Exchange (ETDEWEB)

    Banks, W. F.; Horton, J. H.

    1977-01-01

    This report identifies those potential energy-conservative pipeline innovations that are most energy- and cost-effective, and formulates recommendations for the R, D, and D programs needed to exploit those opportunities. From a candidate field of over twenty classes of efficiency improvements, eight systems are recommended for pursuit. Most of these possess two highly important attributes: large potential energy savings and broad applicability outside the pipeline industry. The R, D, and D program for each improvement and the recommended immediate next step are described. The eight programs recommended for pursuit are: gas-fired combined-cycle compressor station; internally cooled internal combustion engine; methanol-coal slurry pipeline; methanol-coal slurry-fired and coal-fired engines; indirect-fired coal-burning combined-cycle pump station; fuel-cycle pump station; internal coatings in pipelines; and drag-reducing additives in liquid pipelines.

  14. Improved survival of macroencapsulated islets of Langerhans by preimplantation of the immunoisolating device: a morphometric study.

    Science.gov (United States)

    Rafael, E; Wu, G S; Hultenby, K; Tibell, A; Wernerson, A

    2003-01-01

    Encapsulation of cells in a semipermeable membrane may in the future provide an opportunity to treat a variety of endocrine and neurological disorders, without the need for lifelong immunosuppression. The physiological conditions in the device are crucial factors for graft survival. Previously, we have shown that the exchange across the immunoisolating membrane and the microcirculation around the TheraCyte device increase around 3 months after implantation. The aim of this study was to determine whether preimplantation of the TheraCyte device would improve the survival of a later transplanted islet graft. A TheraCyte device was implanted SC on one side of the back of a nondiabetic SD rat. After 3 months, 1500 islets isolated from SD rats were transplanted via the device port. At the same time, another device, loaded with the same number of islets, was implanted on the other side of the back. Both devices were explanted 2 weeks after islet transplantation (i.e., 3.5 months and 0.5 month after device implantation, respectively). Six pairs of devices were evaluated by morphometery. The volume densities of viable islets were 0.22 +/- 0.04 in the preimplanted device vs. 0.06 +/- 0.03 in the nonpreimplanted one (p TheraCyte device seems to improve the survival of an encapsulated islet graft and reduce fibroblast outgrowth in the device.

  15. Improving the accuracy of smart devices to measure noise exposure.

    Science.gov (United States)

    Roberts, Benjamin; Kardous, Chucri; Neitzel, Richard

    2016-11-01

    Occupational noise exposure is one of the most frequent hazards present in the workplace; up to 22 million workers have potentially hazardous noise exposures in the U.S. As a result, noise-induced hearing loss is one of the most common occupational injuries in the U.S. Workers in manufacturing, construction, and the military are at the highest risk for hearing loss. Despite the large number of people exposed to high levels of noise at work, many occupations have not been adequately evaluated for noise exposure. The objective of this experiment was to investigate whether or not iOS smartphones and other smart devices (Apple iPhones and iPods) could be used as reliable instruments to measure noise exposures. For this experiment three different types of microphones were tested with a single model of iPod and three generations of iPhones: the internal microphones on the device, a low-end lapel microphone, and a high-end lapel microphone marketed as being compliant with the International Electrotechnical Commission's (IEC) standard for a Class 2-microphone. All possible combinations of microphones and noise measurement applications were tested in a controlled environment using several different levels of pink noise ranging from 60-100 dBA. Results were compared to simultaneous measurements made using a Type 1 sound level measurement system. Analysis of variance and Tukey's honest significant difference (HSD) test were used to determine if the results differed by microphone or noise measurement application. Levels measured with external microphones combined with certain noise measurement applications did not differ significantly from levels measured with the Type 1 sound measurement system. Results showed that it may be possible to use iOS smartphones and smart devices, with specific combinations of measurement applications and calibrated external microphones, to collect reliable, occupational noise exposure data under certain conditions and within the limitations of the

  16. IMPROVING CO2 EFFICIENCY FOR RECOVERING OIL IN HETEROGENEOUS RESERVOIRS

    International Nuclear Information System (INIS)

    Reid B. Grigg; Robert K. Svec; Zheng-Wen Zeng; Liu Yi; Baojun Bai

    2004-01-01

    A three-year contract for the project, DOE Contract No. DE-FG26-01BC15364, ''Improving CO 2 Efficiency for Recovering Oil in Heterogeneous Reservoirs'', was started on September 28, 2001. This project examines three major areas in which CO 2 flooding can be improved: fluid and matrix interactions, conformance control/sweep efficiency, and reservoir simulation for improved oil recovery. The project has received a one-year, no-cost extension to September 27, 2005. During this extra time additional deliverables will be (1) the version of MASTER that has been debugged and a foam option added for CO 2 mobility control and (2) adsorption/desorption data on pure component minerals common in reservoir rock that will be used to improve predictions of chemical loss to adsorption in reservoirs. This report discusses the activity during the six-month period covering October 1, 2003 through March 31, 2004 that comprises the first and second fiscal quarters of the project's third year. During this period of the project several areas have advanced: reservoir fluid/rock interactions and their relationships to changing injectivity, and surfactant adsorption on quarried core and pure component granules, foam stability, and high flow rate effects. Presentations and papers included: a papers covered in a previous report was presented at the fall SPE ATCE in Denver in October 2003, a presentation at the Southwest ACS meeting in Oklahoma City, presentation on CO 2 flood basic behavior at the Midland Annual CO 2 Conference December 2003; two papers prepared for the biannual SPE/DOE Symposium on IOR, Tulsa, April 2004; one paper accepted for the fall 2004 SPE ATCE in Houston; and a paper submitted to an international journal Journal of Colloid and Interface Science which is being revised after peer review

  17. Improving building energy efficiency in India: State-level analysis of building energy efficiency policies

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Sha; Tan, Qing; Evans, Meredydd; Kyle, Page; Vu, Linh; Patel, Pralit L.

    2017-11-01

    India is expected to add 40 billion m2 of new buildings till 2050. Buildings are responsible for one third of India’s total energy consumption today and building energy use is expected to continue growing driven by rapid income and population growth. The implementation of the Energy Conservation Building Code (ECBC) is one of the measures to improve building energy efficiency. Using the Global Change Assessment Model, this study assesses growth in the buildings sector and impacts of building energy policies in Gujarat, which would help the state adopt ECBC and expand building energy efficiency programs. Without building energy policies, building energy use in Gujarat would grow by 15 times in commercial buildings and 4 times in urban residential buildings between 2010 and 2050. ECBC improves energy efficiency in commercial buildings and could reduce building electricity use in Gujarat by 20% in 2050, compared to the no policy scenario. Having energy codes for both commercial and residential buildings could result in additional 10% savings in electricity use. To achieve these intended savings, it is critical to build capacity and institution for robust code implementation.

  18. An efficiency improvement in warehouse operation using simulation analysis

    Science.gov (United States)

    Samattapapong, N.

    2017-11-01

    In general, industry requires an efficient system for warehouse operation. There are many important factors that must be considered when designing an efficient warehouse system. The most important is an effective warehouse operation system that can help transfer raw material, reduce costs and support transportation. By all these factors, researchers are interested in studying about work systems and warehouse distribution. We start by collecting the important data for storage, such as the information on products, information on size and location, information on data collection and information on production, and all this information to build simulation model in Flexsim® simulation software. The result for simulation analysis found that the conveyor belt was a bottleneck in the warehouse operation. Therefore, many scenarios to improve that problem were generated and testing through simulation analysis process. The result showed that an average queuing time was reduced from 89.8% to 48.7% and the ability in transporting the product increased from 10.2% to 50.9%. Thus, it can be stated that this is the best method for increasing efficiency in the warehouse operation.

  19. Improving computational efficiency of Monte Carlo simulations with variance reduction

    International Nuclear Information System (INIS)

    Turner, A.; Davis, A.

    2013-01-01

    CCFE perform Monte-Carlo transport simulations on large and complex tokamak models such as ITER. Such simulations are challenging since streaming and deep penetration effects are equally important. In order to make such simulations tractable, both variance reduction (VR) techniques and parallel computing are used. It has been found that the application of VR techniques in such models significantly reduces the efficiency of parallel computation due to 'long histories'. VR in MCNP can be accomplished using energy-dependent weight windows. The weight window represents an 'average behaviour' of particles, and large deviations in the arriving weight of a particle give rise to extreme amounts of splitting being performed and a long history. When running on parallel clusters, a long history can have a detrimental effect on the parallel efficiency - if one process is computing the long history, the other CPUs complete their batch of histories and wait idle. Furthermore some long histories have been found to be effectively intractable. To combat this effect, CCFE has developed an adaptation of MCNP which dynamically adjusts the WW where a large weight deviation is encountered. The method effectively 'de-optimises' the WW, reducing the VR performance but this is offset by a significant increase in parallel efficiency. Testing with a simple geometry has shown the method does not bias the result. This 'long history method' has enabled CCFE to significantly improve the performance of MCNP calculations for ITER on parallel clusters, and will be beneficial for any geometry combining streaming and deep penetration effects. (authors)

  20. Restructuring and energy efficiency improvement of the Bulgarian energy economy

    International Nuclear Information System (INIS)

    Moumdjian, G.

    1993-01-01

    The structure of the national energy economy of Bulgaria implies characteristic features that specify low efficiency as regards power production, ecology and economics. Even the qualitative assessments show that these indices stand far away from the standards established in developed countries like Denmark, Finland, Sweden, etc. The best starting position for harmful energy efficiency improvement as well as emission reduction must be based on the restructuring of energy economy. The strategy of restructuring and development of energy economy covers the whole integrated national energy flow system 'resources - end user'. The preliminary study shows that energy efficiency can be increased by 25-30% within a period of 6-10 years using the least-cost investment strategy (including the research and development activities expenses). The study covers the existing structure of energy sector. Scenarios are being elaborated for its development and restructuring in respect to: heat production and transfer; electricity generation and transmission; energy consumption and conservation in residential buildings, public buildings and commercial sector; energy consumption in transport sector and agriculture. The approach for identification of the real potential opportunities in relation to the above stated areas is based on mathematical statistics and stochastic differential equations, multicriterial assessments, approach of self organisation systems and demand-side management. (author)

  1. Evaluating the Management System Approach for Industrial Energy Efficiency Improvements

    Directory of Open Access Journals (Sweden)

    Thomas Zobel

    2016-09-01

    Full Text Available Voluntary environmental management systems (EMS based on the international standard ISO 14001 have become widespread globally in recent years. The purpose of this study is to assess the impact of voluntary management systems on energy efficiency in the Swedish manufacturing industry by means of objective industrial energy data derived from mandatory annual environmental reports. The study focuses on changes in energy efficiency over a period of 12 years and includes both ISO 14001-certified companies and non-certified companies. Consideration is given to energy improvement efforts in the companies before the adoption of ISO 14001. The analysis has been carried out using statistical methods for two different industrial energy parameters: electricity and fossil fuel consumption. The results indicate that ISO 14001 adoption and certification has increased energy efficiency regarding the use of fossil fuel. In contrast, no effect of the management systems has been found concerning the use of electricity. The mixed results of this study are only partly in line with the results of previous studies based on perceptions of company representatives.

  2. Mixing of phosphorescent and exciplex emission in efficient organic electroluminescent devices.

    Science.gov (United States)

    Cherpak, Vladyslav; Stakhira, Pavlo; Minaev, Boris; Baryshnikov, Gleb; Stromylo, Evgeniy; Helzhynskyy, Igor; Chapran, Marian; Volyniuk, Dmytro; Hotra, Zenon; Dabuliene, Asta; Tomkeviciene, Ausra; Voznyak, Lesya; Grazulevicius, Juozas Vidas

    2015-01-21

    We fabricated a yellow organic light-emitting diode (OLED) based on the star-shaped donor compound tri(9-hexylcarbazol-3-yl)amine, which provides formation of the interface exciplexes with the iridium(III) bis[4,6-difluorophenyl]-pyridinato-N,C2']picolinate (FIrpic). The exciplex emission is characterized by a broad band and provides a condition to realize the highly effective white OLED. It consists of a combination of the blue phosphorescent emission from the FIrpic complex and a broad efficient delayed fluorescence induced by thermal activation with additional direct phosphorescence from the triplet exciplex formed at the interface. The fabricated exciplex-type device exhibits a high brightness of 38 000 cd/m(2) and a high external quantum efficiency.

  3. RADIO FREQUENCY IDENTIFICATION DEVICES: EFFECTIVENESS IN IMPROVING SAFEGUARDS AT GAS-CENTRIFUGE URANIUM-ENRICHMENT PLANTS

    International Nuclear Information System (INIS)

    JOE, J.

    2007-01-01

    Recent advances in radio frequency identification devices (RFIDs) have engendered a growing interest among international safeguards experts. Potentially, RFIDs could reduce inspection work, viz. the number of inspections, number of samples, and duration of the visits, and thus improve the efficiency and effectiveness of international safeguards. This study systematically examined the applications of RFIDs for IAEA safeguards at large gas-centrifuge enrichment plants (GCEPs). These analyses are expected to help identify the requirements and desirable properties for RFIDs, to provide insights into which vulnerabilities matter most, and help formulate the required assurance tests. This work, specifically assesses the application of RFIDs for the ''Option 4'' safeguards approach, proposed by Bruce Moran, U. S. Nuclear Regulatory Commission (NRC), for large gas-centrifuge uranium-enrichment plants. The features of ''Option 4'' safeguards include placing RFIDs on all feed, product and tails (F/P/T) cylinders, along with WID readers in all FP/T stations and accountability scales. Other features of Moran's ''Option 4'' are Mailbox declarations, monitoring of load-cell-based weighing systems at the F/P/T stations and accountability scales, and continuous enrichment monitors. Relevant diversion paths were explored to evaluate how RFIDs improve the efficiency and effectiveness of safeguards. Additionally, the analysis addresses the use of RFIDs in conjunction with video monitoring and neutron detectors in a perimeter-monitoring approach to show that RFIDs can help to detect unidentified cylinders

  4. Improving thermoelectric energy harvesting efficiency by using graphene

    Directory of Open Access Journals (Sweden)

    Muhammad Usman

    2016-05-01

    Full Text Available This study is aimed at enhancing the efficiency of a thermoelectric (TE energy harvesting system by using a thick graphene layer. This method is a simple yet effective way to increase the temperature gradient across a conventional TE module by accelerating heat dissipation on the cold side of the system. Aqueous dispersions of graphene were used to prepare a 112-μm thick graphene layer on the cold side of the TE system with aluminum as the substrate material. The maximum efficiency of the proposed system was improved by 25.45 %, as compared to the conventional TE system, which does not have a graphene layer. Additionally, the proposed system shows very little performance deterioration (2.87 % in the absence of enough air flow on the cold side of the system, compared to the case of the conventional system (10.59 %. Hence, the proposed system, when coupled with the latest research on high performance TE materials, presents a groundbreaking improvement in the practical application of the TE energy harvesting systems.

  5. Assembly Line Efficiency Improvement by Using WITNESS Simulation Software

    Science.gov (United States)

    Yasir, A. S. H. M.; Mohamed, N. M. Z. N.

    2018-03-01

    In the nowadays-competitive world, efficiencies and the productivity of the assembly line are essential in manufacturing company. This paper demonstrates the study of the existing production line performance. The actual cycle time observed and recorded during the working process. The current layout was designed and analysed using Witness simulation software. The productivity and effectiveness for every single operator are measured to determine the operator idle time and busy time. Two new alternatives layout were proposed and analysed by using Witness simulation software to improve the performance of production activities. This research provided valuable and better understanding of production effectiveness by adjusting the line balancing. After analysing the data, simulation result from the current layout and the proposed plan later been tabulated to compare the improved efficiency and productivity. The proposed design plan has shown an increase in yield and productivity compared to the current arrangement. This research has been carried out in company XYZ, which is one of the automotive premises in Pahang, Malaysia.

  6. Enhanced policies for the improvement of electricity efficiencies

    International Nuclear Information System (INIS)

    Blok, Kornelis

    2005-01-01

    Energy-efficiency improvement is considered as an important option to limit greenhouse gas emissions. In this paper, the possibilities to implement new policies to improve the efficiency of electricity end-use are explored. The following policy actions are considered: - introduction of a '1 W standard' for standby power consumption of appliances;- incremental standards for large electric appliances;- design guidelines for small electric appliances;- a technology-forcing standard for lighting;- a motor-drive program;- a program directed at the reduction of electricity use during empty-office hours;- actual energy performance requirements for service-sector buildings. The implementation of these programs will contribute substantially to reaching greenhouse gas emission targets in the European Union (total estimated effect to be 200-350 Mton CO 2 emission reduction in the year 2020). However, to reach these targets a very substantial effort is required, both in terms of policy ambition, force of the applied instruments, and implementation efforts. In the case of electric appliances, regulatory instruments may need wider application. And, in order to attain the substantial potential savings in motor-drive systems, an effort comparable to the effort to promote renewable electricity in the European Union may be both justified and necessary

  7. Training directionally selective motion pathways can significantly improve reading efficiency

    Science.gov (United States)

    Lawton, Teri

    2004-06-01

    This study examined whether perceptual learning at early levels of visual processing would facilitate learning at higher levels of processing. This was examined by determining whether training the motion pathways by practicing leftright movement discrimination, as found previously, would improve the reading skills of inefficient readers significantly more than another computer game, a word discrimination game, or the reading program offered by the school. This controlled validation study found that practicing left-right movement discrimination 5-10 minutes twice a week (rapidly) for 15 weeks doubled reading fluency, and significantly improved all reading skills by more than one grade level, whereas inefficient readers in the control groups barely improved on these reading skills. In contrast to previous studies of perceptual learning, these experiments show that perceptual learning of direction discrimination significantly improved reading skills determined at higher levels of cognitive processing, thereby being generalized to a new task. The deficits in reading performance and attentional focus experienced by the person who struggles when reading are suggested to result from an information overload, resulting from timing deficits in the direction-selectivity network proposed by Russell De Valois et al. (2000), that following practice on direction discrimination goes away. This study found that practicing direction discrimination rapidly transitions the inefficient 7-year-old reader to an efficient reader.

  8. Maximum Efficiency of Thermoelectric Heat Conversion in High-Temperature Power Devices

    Directory of Open Access Journals (Sweden)

    V. I. Khvesyuk

    2016-01-01

    Full Text Available Modern trends in development of aircraft engineering go with development of vehicles of the fifth generation. The features of aircrafts of the fifth generation are motivation to use new high-performance systems of onboard power supply. The operating temperature of the outer walls of engines is of 800–1000 K. This corresponds to radiation heat flux of 10 kW/m2 . The thermal energy including radiation of the engine wall may potentially be converted into electricity. The main objective of this paper is to analyze if it is possible to use a high efficiency thermoelectric conversion of heat into electricity. The paper considers issues such as working processes, choice of materials, and optimization of thermoelectric conversion. It presents the analysis results of operating conditions of thermoelectric generator (TEG used in advanced hightemperature power devices. A high-temperature heat source is a favorable factor for the thermoelectric conversion of heat. It is shown that for existing thermoelectric materials a theoretical conversion efficiency can reach the level of 15–20% at temperatures up to 1500 K and available values of Ioffe parameter being ZT = 2–3 (Z is figure of merit, T is temperature. To ensure temperature regime and high efficiency thermoelectric conversion simultaneously it is necessary to have a certain match between TEG power, temperature of hot and cold surfaces, and heat transfer coefficient of the cooling system. The paper discusses a concept of radiation absorber on the TEG hot surface. The analysis has demonstrated a number of potentialities for highly efficient conversion through using the TEG in high-temperature power devices. This work has been implemented under support of the Ministry of Education and Science of the Russian Federation; project No. 1145 (the programme “Organization of Research Engineering Activities”.

  9. Improved efficiency in organic/inorganic hybrid solar cells by interfacial modification of ZnO nanowires with small molecules

    International Nuclear Information System (INIS)

    Chang, Sehoon; Park, Hyesung; Cheng, Jayce J; Rekemeyer, Paul H; Gradečak, Silvija

    2014-01-01

    We demonstrate improved photovoltaic performance of ZnO nanowire/poly(3-hexylthiophene) (P3HT) nanofiber hybrid devices using an interfacial modification of ZnO nanowires. Formation of cascade energy levels between the ZnO nanowire and P3HT nanofiber was achieved by interfacial modification of ZnO nanowires using small molecules tetraphenyldibenzoperiflanthene (DBP) and 3,4,9,10-perylenetetracarboxylic bisbenzimidazole (PTCBI). The successful demonstration of improved device performance owing to the cascade energy levels by small molecule modification is a promising approach toward highly efficient organic/inorganic hybrid solar cells. (paper)

  10. [Study on the reform and improvement of the medical device registration system in China].

    Science.gov (United States)

    Wang, Lanming

    2012-11-01

    Based on the theories of the Government Regulation and Administrative Licensure, aiming at the current situations of medical device registration system in China, some policy suggestions for future reform and improvement were provided as follows. (1) change the concepts of medical device registration administration. (2) perfect the regulations of medical device registration administration. (3) reform the medical device review organizational system. (4) Optimize the procedure of review and approval. (5) set up and maintain a professional team of review and approval staff. (6) reinforce the post-marketing supervision of medical devices. (7) foster and bring into play of the role of non-government organizations.

  11. Device Engineering Towards Improved Tin Sulfide Solar Cell Performance and Performance Reproducibility

    Energy Technology Data Exchange (ETDEWEB)

    Steinmann, Vera; Chakraborty, Rupak; Rekemeyer, Paul; Siol, Sebastian; Martinot, Loic; Polizzotti, Alex; Yang, Chuanxi; Hartman, Katy; Gradecak, Silvija; Zakutayev, Andriy; Gordon, Roy G.; Buonassisi, Tonio

    2016-11-21

    As novel absorber materials are developed and screened for their photovoltaic (PV) properties, the challenge remains to rapidly test promising candidates in high-performing PV devices. There is a need to engineer new compatible device architectures, including the development of novel transparent conductive oxides and buffer layers. Here, we consider the two approaches of a substrate-style and a superstrate-style device architecture for novel thin-film solar cells. We use tin sulfide as a test absorber material. Upon device engineering, we demonstrate new approaches to improve device performance and performance reproducibility.

  12. Influence of the ambient temperature on the cooling efficiency of the high performance cooling device with thermosiphon effect

    Science.gov (United States)

    Nemec, Patrik; Malcho, Milan

    2018-06-01

    This work deal with experimental measurement and calculation cooling efficiency of the cooling device working with a heat pipe technology. The referred device in the article is cooling device capable transfer high heat fluxes from electric elements to the surrounding. The work contain description, working principle and construction of cooling device. The main factor affected the dissipation of high heat flux from electronic elements through the cooling device to the surrounding is condenser construction, its capacity and option of heat removal. Experimental part describe the measuring method cooling efficiency of the cooling device depending on ambient temperature in range -20 to 40°C and at heat load of electronic components 750 W. Measured results are compared with results calculation based on physical phenomena of boiling, condensation and natural convection heat transfer.

  13. Device for improved air and fuel distribution to a combustor

    Science.gov (United States)

    Laster, Walter R.; Schilp, Reinhard

    2016-05-31

    A flow conditioning device (30, 50, 70, 100, 150) for a can annular gas turbine engine, including a plurality of flow elements (32, 34, 52, 54, 72, 74, 102) disposed in a compressed air flow path (42, 60, 80, 114, 122) leading to a combustor (12), configured such that relative adjustment of at least one flow directing element (32, 52, 72, 110) with respect to an adjacent flow directing element (34, 54, 74, 112, 120) during operation of the gas turbine engine is effective to adjust a level of choking of the compressed air flow path (42, 60, 80, 114, 122).

  14. Improvement of a device for monitoring the contamination of surfaces

    International Nuclear Information System (INIS)

    Barbier, Albert.

    1981-01-01

    The purpose of this invention is to make it possible to monitor the contamination of surfaces by a light weight portable device and enabling the alpha, beta and gamma radiation contamination to be detected. The detection probe which is connected by a single lead to the box is adapted, in each particular case, to the radiation mode emitted by the contaminated surfaces and the box is provided with a special leak-proof socket for connecting the probe and includes means for assessing the counting rate of the radiation given off, depending on the mode of the radiations emitted by the contaminated surfaces and the intensity of the count rate [fr

  15. Field Performance versus Standard Test Condition Efficiency of Tandem Solar Cells and the Specific Case of Perovskites/Silicon Devices

    KAUST Repository

    Dupre, Olivier; Niesen, Bjö rn; De Wolf, Stefaan; Ballif, Christophe

    2018-01-01

    efficiencies and calculate their energy yields using field data from Denver. We find that annual losses due to differences between operating conditions and standard test conditions are similar for single-junction and four-terminal tandem devices. The additional

  16. Energy-Efficient Scheduling for Hybrid Tasks in Control Devices for the Internet of Things

    Science.gov (United States)

    Gao, Zhigang; Wu, Yifan; Dai, Guojun; Xia, Haixia

    2012-01-01

    In control devices for the Internet of Things (IoT), energy is one of the critical restriction factors. Dynamic voltage scaling (DVS) has been proved to be an effective method for reducing the energy consumption of processors. This paper proposes an energy-efficient scheduling algorithm for IoT control devices with hard real-time control tasks (HRCTs) and soft real-time tasks (SRTs). The main contribution of this paper includes two parts. First, it builds the Hybrid tasks with multi-subtasks of different function Weight (HoW) task model for IoT control devices. HoW describes the structure of HRCTs and SRTs, and their properties, e.g., deadlines, execution time, preemption properties, and energy-saving goals, etc. Second, it presents the Hybrid Tasks' Dynamic Voltage Scaling (HTDVS) algorithm. HTDVS first sets the slowdown factors of subtasks while meeting the different real-time requirements of HRCTs and SRTs, and then dynamically reclaims, reserves, and reuses the slack time of the subtasks to meet their ideal energy-saving goals. Experimental results show HTDVS can reduce energy consumption about 10%–80% while meeting the real-time requirements of HRCTs, HRCTs help to reduce the deadline miss ratio (DMR) of systems, and HTDVS has comparable performance with the greedy algorithm and is more favorable to keep the subtasks' ideal speeds. PMID:23112659

  17. Energy-Efficient Scheduling for Hybrid Tasks in Control Devices for the Internet of Things

    Directory of Open Access Journals (Sweden)

    Guojun Dai

    2012-08-01

    Full Text Available In control devices for the Internet of Things (IoT, energy is one of the critical restriction factors. Dynamic voltage scaling (DVS has been proved to be an effective method for reducing the energy consumption of processors. This paper proposes an energy-efficient scheduling algorithm for IoT control devices with hard real-time control tasks (HRCTs and soft real-time tasks (SRTs. The main contribution of this paper includes two parts. First, it builds the Hybrid tasks with multi-subtasks of different function Weight (HoW task model for IoT control devices. HoW describes the structure of HRCTs and SRTs, and their properties, e.g., deadlines, execution time, preemption properties, and energy-saving goals, etc. Second, it presents the Hybrid Tasks’ Dynamic Voltage Scaling (HTDVS algorithm. HTDVS first sets the slowdown factors of subtasks while meeting the different real-time requirements of HRCTs and SRTs, and then dynamically reclaims, reserves, and reuses the slack time of the subtasks to meet their ideal energy-saving goals. Experimental results show HTDVS can reduce energy consumption about 10%–80% while meeting the real-time requirements of HRCTs, HRCTs help to reduce the deadline miss ratio (DMR of systems, and HTDVS has comparable performance with the greedy algorithm and is more favorable to keep the subtasks’ ideal speeds.

  18. Efficient perturbation theory to improve the density matrix renormalization group

    Science.gov (United States)

    Tirrito, Emanuele; Ran, Shi-Ju; Ferris, Andrew J.; McCulloch, Ian P.; Lewenstein, Maciej

    2017-02-01

    The density matrix renormalization group (DMRG) is one of the most powerful numerical methods available for many-body systems. It has been applied to solve many physical problems, including the calculation of ground states and dynamical properties. In this work, we develop a perturbation theory of the DMRG (PT-DMRG) to greatly increase its accuracy in an extremely simple and efficient way. Using the canonical matrix product state (MPS) representation for the ground state of the considered system, a set of orthogonal basis functions {| ψi> } is introduced to describe the perturbations to the ground state obtained by the conventional DMRG. The Schmidt numbers of the MPS that are beyond the bond dimension cutoff are used to define these perturbation terms. The perturbed Hamiltonian is then defined as H˜i j= ; its ground state permits us to calculate physical observables with a considerably improved accuracy compared to the original DMRG results. We benchmark the second-order perturbation theory with the help of a one-dimensional Ising chain in a transverse field and the Heisenberg chain, where the precision of the DMRG is shown to be improved O (10 ) times. Furthermore, for moderate L the errors of the DMRG and PT-DMRG both scale linearly with L-1 (with L being the length of the chain). The linear relation between the dimension cutoff of the DMRG and that of the PT-DMRG at the same precision shows a considerable improvement in efficiency, especially for large dimension cutoffs. In the thermodynamic limit we show that the errors of the PT-DMRG scale with √{L-1}. Our work suggests an effective way to define the tangent space of the ground-state MPS, which may shed light on the properties beyond the ground state. This second-order PT-DMRG can be readily generalized to higher orders, as well as applied to models in higher dimensions.

  19. Implementing electronic handover: interventions to improve efficiency, safety and sustainability.

    Science.gov (United States)

    Alhamid, Sharifah Munirah; Lee, Desmond Xue-Yuan; Wong, Hei Man; Chuah, Matthew Bingfeng; Wong, Yu Jun; Narasimhalu, Kaavya; Tan, Thuan Tong; Low, Su Ying

    2016-10-01

    Effective handovers are critical for patient care and safety. Electronic handover tools are increasingly used today to provide an effective and standardized platform for information exchange. The implementation of an electronic handover system in tertiary hospitals can be a major challenge. Previous efforts in implementing an electronic handover tool failed due to poor compliance and buy-in from end-users. A new electronic handover tool was developed and incorporated into the existing electronic medical records (EMRs) for medical patients in Singapore General Hospital (SGH). There was poor compliance by on-call doctors in acknowledging electronic handovers, and lack of adherence to safety rules, raising concerns about the safety and efficiency of the electronic handover tool. Urgent measures were needed to ensure its safe and sustained use. A quality improvement group comprising stakeholders, including end-users, developed multi-faceted interventions using rapid PDSA (P-Plan, D-Do, S-Study, A-Act ) cycles to address these issues. Innovative solutions using media and online software provided cost-efficient measures to improve compliance. The percentage of unacknowledged handovers per day was used as the main outcome measure throughout all PDSA cycles. Doctors were also assessed for improvement in their knowledge of safety rules and their perception of the electronic handover tool. An electronic handover tool complementing daily clinical practice can be successfully implemented using solutions devised through close collaboration with end-users supported by the senior leadership. A combined 'bottom-up' and 'top-down' approach with regular process evaluations is crucial for its long-term sustainability. © The Author 2016. Published by Oxford University Press in association with the International Society for Quality in Health Care. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. Improved energy efficiency in juice production through waste heat recycling

    International Nuclear Information System (INIS)

    Anderson, J.-O.; Elfgren, E.; Westerlund, L.

    2014-01-01

    Highlights: • A heating system at a juice production was investigated and improved. • Different impacts of drying cycle improvements at the energy usage were explored. • The total heat use for drying could thereby be decreased with 52%. • The results point out a significant decrease of heat consumption with low investment costs. - Abstract: Berry juice concentrate is produced by pressing berries and heating up the juice. The by-products are berry skins and seeds in a press cake. Traditionally, these by-products have been composted, but due to their valuable nutrients, it could be profitable to sell them instead. The skins and seeds need to be separated and dried to a moisture content of less than 10 %wt (on dry basis) in order to avoid fermentation. A berry juice plant in the north of Sweden has been studied in order to increase the energy and resource efficiency, with special focus on the drying system. This was done by means of process integration with mass and energy balance, theory from thermodynamics and psychrometry along with measurements of the juice plant. Our study indicates that the drying system could be operated at full capacity without any external heat supply using waste heat supplied from the juice plant. This would be achieved by increasing the efficiency of the dryer by recirculation of the drying air and by heat supply from the flue gases of the industrial boiler. The recirculation would decrease the need of heat in the dryer with about 52%. The total heat use for the plant could thereby be decreased from 1262 kW to 1145 kW. The improvements could be done without compromising the production quality

  1. The effect of device-based cardiac contractility modulation therapy on myocardial efficiency and oxidative metabolism in patients with heart failure

    International Nuclear Information System (INIS)

    Goliasch, Georg; Khorsand, Aliasghar; Sochor, Heinz; Schmidinger, Herwig; Graf, Senta; Schuetz, Matthias; Karanikas, Georgios; Khazen, Cesar; Wolzt, Michael

    2012-01-01

    Cardiac contractility modulation (CCM) is a device-based therapy that involves delivery of nonexcitatory electrical signals resulting in improved ventricular function and a reversal of maladaptive cardiac fetal gene programmes. Our aim was to evaluate whether acute application of CCM leads to an increase in myocardial oxygen consumption (MVO 2 ) in patients with chronic heart failure using 11 C-acetate positron emission tomography (PET). We prospectively enrolled 21 patients with severe heart failure. 11 C-acetate PET was performed before and after activation of the CCM device. In 12 patients an additional stress study with dobutamine was performed. Under resting conditions, the values of myocardial blood flow (MBF), MVO 2 and work metabolic index (WMI, reflecting myocardial efficiency) with the CCM device activated did not differ significantly from the values with the device deactivated. MBF was 0.81 ± 0.18 ml min -1 g -1 with the device off and 0.80 ± 0.15 ml min -1 g -1 with the device on (p = 0.818), MVO 2 was 6.81 ± 1.69 ml/min/100 g with the device off and 7.15 ± 1.62 ml/min/100 g with the device on (p = 0.241) and WMI was 4.94 ± 1.14 mmHg ml/m 2 with the device off and 5.21 ± 1.36 mmHg ml/m 2 with the device on (p = 0.344). Under dobutamine stress, the values of MBF, MVO 2 and WMI with the CCM device activated did not differ from the values with the device deactivated, but were significantly increased compared with the values obtained under resting conditions. These results indicate that CCM does not induce increased MVO 2 , even under stress conditions. (orig.)

  2. The effect of device-based cardiac contractility modulation therapy on myocardial efficiency and oxidative metabolism in patients with heart failure

    Energy Technology Data Exchange (ETDEWEB)

    Goliasch, Georg; Khorsand, Aliasghar; Sochor, Heinz; Schmidinger, Herwig; Graf, Senta [Vienna General Hospital/Medical University of Vienna, Department of Cardiology, Vienna (Austria); Schuetz, Matthias; Karanikas, Georgios [Vienna General Hospital/Medical University of Vienna, Department of Nuclear Medicine, Vienna (Austria); Khazen, Cesar [Vienna General Hospital/ Medical University of Vienna, Department of Cardiothoracic Surgery, Vienna (Austria); Wolzt, Michael [Vienna General Hospital/Medical University of Vienna, Department of Cardiology, Vienna (Austria); Vienna General Hospital/ Medical University of Vienna, Department of Clinical Pharmacology, Vienna (Austria)

    2012-03-15

    Cardiac contractility modulation (CCM) is a device-based therapy that involves delivery of nonexcitatory electrical signals resulting in improved ventricular function and a reversal of maladaptive cardiac fetal gene programmes. Our aim was to evaluate whether acute application of CCM leads to an increase in myocardial oxygen consumption (MVO{sub 2}) in patients with chronic heart failure using {sup 11}C-acetate positron emission tomography (PET). We prospectively enrolled 21 patients with severe heart failure. {sup 11}C-acetate PET was performed before and after activation of the CCM device. In 12 patients an additional stress study with dobutamine was performed. Under resting conditions, the values of myocardial blood flow (MBF), MVO{sub 2} and work metabolic index (WMI, reflecting myocardial efficiency) with the CCM device activated did not differ significantly from the values with the device deactivated. MBF was 0.81 {+-} 0.18 ml min{sup -1} g{sup -1} with the device off and 0.80 {+-} 0.15 ml min{sup -1} g{sup -1} with the device on (p = 0.818), MVO{sub 2} was 6.81 {+-} 1.69 ml/min/100 g with the device off and 7.15 {+-} 1.62 ml/min/100 g with the device on (p = 0.241) and WMI was 4.94 {+-} 1.14 mmHg ml/m{sup 2} with the device off and 5.21 {+-} 1.36 mmHg ml/m{sup 2} with the device on (p = 0.344). Under dobutamine stress, the values of MBF, MVO{sub 2} and WMI with the CCM device activated did not differ from the values with the device deactivated, but were significantly increased compared with the values obtained under resting conditions. These results indicate that CCM does not induce increased MVO{sub 2}, even under stress conditions. (orig.)

  3. Improvement in the diffraction efficiency of a polymer using an ionic liquid

    Directory of Open Access Journals (Sweden)

    Kim Sung Ho

    2018-01-01

    Full Text Available In this paper, photosensitive materials for information storage devices are presented. The polymers were prepared using surface relief-grating (SRG fabrication with a diode-pumped solid-state (DPSS laser of 532 nm, and the diffraction efficiency (DE of the polymers were assessed with a low-power DPSS laser at 633 nm. However, the diffraction efficiency of the azo-functionalized epoxy-based polymer was low, even after 15 min of exposure. To improve the efficiency and reduce the time it takes for the DE measurements of the photosensitive polymer, the polymer was combined ionic liquids (ILs. Various ILs, i.e., 1-methylimidazolium chloride ([Mim]Cl from the imidazolium family of ILs and diethylammonium dihydrogen phosphate (DEAP, triethylammonium 4-aminotoluene-3-sulfonic acid (TASA and tributylmethylammonium methyl sulphate (TBMS from the ammonium family of ILs, were investigated. For the first time, it was observed that DE dramatically increased the DEAP–polymer mixture in 4 min compared to the polymer (alone and other polymer–IL mixtures. Therefore, DEAP IL could help improve the efficiency of DE measurements in a shorter time.

  4. Improving The Efficiency Of Ammonia Electrolysis For Hydrogen Production

    Science.gov (United States)

    Palaniappan, Ramasamy

    Given the abundance of ammonia in domestic and industrial wastes, ammonia electrolysis is a promising technology for remediation and distributed power generation in a clean and safe manner. Efficiency has been identified as one of the key issues that require improvement in order for the technology to enter the market phase. Therefore, this research was performed with the aim of improving the efficiency of hydrogen production by finding alternative materials for the cathode and electrolyte. 1. In the presence of ammonia the activity for hydrogen evolution reaction (HER) followed the trend Rh>Pt>Ru>Ni. The addition of ammonia resulted in lower rates for HER for Pt, Ru, and Ni, which have been attributed to competition from the ammonia adsorption reaction. 2. The addition of ammonia offers insight into the role of metal-hydrogen underpotential deposition (M-Hupd) on HER kinetics. In addition to offering competition via ammonia adsorption it resulted in fewer and weaker M-Hupd bonds for all metals. This finding substantiates the theory that M-Hupd bonds favor HER on Pt electrocatalyst. However, for Rh results suggest that M-Hupd bond may hinder the HER. In addition, the presence of unpaired valence shell electrons is suggested to provide higher activity for HER in the presence of ammonia. 3. Bimetals PtxM1-x (M = Ir, Ru, Rh, and Ni) offered lower overpotentials for HER compared to the unalloyed metals in the presence of ammonia. The activity of HER in the presence of ammonia follows the trend Pt-Ir>Pt-Rh>Pt-Ru>Pt-Ni. The higher activity of HER is attributed to the synergistic effect of the alloy, where ammonia adsorbs onto the more electropositive alloying metal leaving Pt available for Hupd formation and HER to take place. Additionally, this supports the theory that the presence of a higher number of unpaired electrons favors the HER in the presence of ammonia. 4. Potassium polyacrylate (PAA-K) was successfully used as a substitute for aqueous KOH for ammonia

  5. Loop heat pipes - highly efficient heat-transfer devices for systems of sun heat supply

    Energy Technology Data Exchange (ETDEWEB)

    Maydanik, Yu. [Ural Branch of the Russian Academy of Sciences, Ekaterinburg (Russian Federation). Inst. of Thermophysics

    2004-07-01

    Loop heat pipes (LHPs) are hermetic heat-transfer devices operating on a closed evaporation-condensation cycle with the use of capillary pressure for pumping the working fluid [1]. In accordance with this, they possess all the main advantages of conventional heat pipes, but, as distinct from the latter, have a considerably higher heat-transfer capacity, especially when operating in the ''antigravity'' regime, when heat is transferred from above downwards. Besides, LHPs possess a higher functional versatility, are adaptable to different operating conditions and provide great scope for various design embodiments. This is achieved at the expense of both the original design of the device and the properties of the wick - a special capillary structure used for the creation of capillary pressure. The LHP schematic diagram is given in Fig. 1. The device contains an evaporator and a condenser - heat exchanger connected by means of smooth-walled pipe-lines with a relatively small diameter intended for separate motion of vapor and liquid. At present loop heat pipes are most extensively employed in thermoregulation systems of spacecrafts. Miniature LHPs are used for cooling electronics and computers. At the same time there exists a considerable potential of using these devices for the recovery of low-grade (waste) heat from different sources, and also in systems of sun heat supply. In the latter case LHPs may serve as an efficient heat-transfer link between a sun collector and a heat accumulator, which has a low thermal resistance and does not consume any additional energy for pumping the working fluid between them. (orig.)

  6. High-efficiency and heavily doped organic light-emitting devices based on quench-resistant red iridium complex

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Qi [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu 610054 (China); Yu, Junsheng, E-mail: jsyu@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu 610054 (China); Zhao, Juan; Wang, Jun [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China, Chengdu 610054 (China); Li, Ming [College of Chemistry, Sichuan University, Chengdu 610064 (China); Lu, Zhiyun, E-mail: luzhiyun@scu.edu.cn [College of Chemistry, Sichuan University, Chengdu 610064 (China)

    2013-02-15

    Highly efficient red phosphorescent organic light-emitting devices had been fabricated using a new iridium complex, bis[2-(9,9-dimethyl-9H-fluoren-2-yl) benzothiazolato-N,C{sup 2'}]iridium(III) (acetylacetonate) [(fbt){sub 2}Ir(acac)] as phosphor. With a high doping concentration of 15 wt%, the device exhibited a maximum luminance efficiency, power efficiency and external quantum efficiency (EQE) of 35.2 cd/A, 21.3 lm/W, 18.2%, respectively, indicating an excellent quench-resistant property of (fbt){sub 2}Ir(acac). The results are appealing towards the development of 'easy-to-make' OLEDs. It has been demonstrated that the high efficiency arises from more balanced charge carriers in the emissive layer. - Highlight: Black-Right-Pointing-Pointer We obtained efficient OLEDs based on newly synthesized quench-resistant phosphor. Black-Right-Pointing-Pointer Peak performance was obtained with 15 wt% (fbt){sub 2}Ir(acac) doped device. Black-Right-Pointing-Pointer Our devices gave one of the best performance among heavily-doped red devices. Black-Right-Pointing-Pointer Balanced carrier transport is crucial for the high performance of our devices.

  7. The improving of sodium cleaning device with atomized water

    International Nuclear Information System (INIS)

    Guo Huanfang; Zhang Xiufeng; Yu Chunli; Hong Shunzhang; Xing Chaoqing; Yuan Waimei

    1999-04-01

    The atomized water in N 2 under pressure can react with sodium on the sodium-soiled surfaces under control. This method has the following main advantages: The reaction proceeds at room temperature; high efficiency; fast reaction velocity; small quantity of water; the mechanical and/or corrosion damage by sodium reaction products can be avoided. The results of washing fuel element of CEFR (China Experimental Fast Reactor) were satisfactory

  8. Improving Dryer and Press Efficiencies Through Combustion of Hydrocarbon Emissions

    Energy Technology Data Exchange (ETDEWEB)

    Sujit Banerjee

    2005-10-31

    Emission control devices on dryers and presses have been legislated into the industry, and are now an integral part of the drying system. These devices consume large quantities of natural gas and electricity and down-sizing or eliminating them will provide major energy savings. The principal strategy taken here focuses on developing process changes that should minimize (and in some cases eliminate) the need for controls. A second approach is to develop lower-cost control options. It has been shown in laboratory and full-scale work that Hazardous Air Pollutants (HAPs) emerge mainly at the end of the press cycle for particleboard, and, by extension, to other prod-ucts. Hence, only the air associated with this point of the cycle need be captured and treated. A model for estimating terpene emissions in the various zones of veneer dryers has been developed. This should allow the emissions to be concentrated in some zones and minimized in others, so that some of the air could be directly released without controls. Low-cost catalysts have been developed for controlling HAPs from dryers and presses. Catalysts conventionally used for regenerative catalytic oxidizers can be used at much lower temperatures for treating press emissions. Fluidized wood ash is an especially inexpensive mate-rial for efficiently reducing formaldehyde in dryer emissions. A heat transfer model for estimating pinene emissions from hot-pressing strand for the manufacture of flakeboard has been constructed from first principles and validated. The model shows that most of the emissions originate from the 1-mm layer of wood adjoining the platen surface. Hence, a simple control option is to surface a softwood mat with a layer of hardwood prior to pressing. Fines release a disproportionate large quantity of HAPs, and it has been shown both theo-retically and in full-scale work that particles smaller than 400 µm are principally responsible. Georgia-Pacific is considering green

  9. Efficiency improvement for a sustainable agriculture : the integration of agronomic and farm economics approaches

    OpenAIRE

    Koeijer, de, T.J.

    2002-01-01

    Keywords: Sustainable farming systems, Agronomic efficiency, Economic efficiency, Environmental efficiency, Sustainability index, Interdisciplinary analysis.

    The objective of the research described in this thesis was to determine what role improved agronomic efficiency can play in the transition towards more sustainable production systems. Agronomic efficiency measures the technical performance. If it could be improved, environmental damage could be reduced while, at the sam...

  10. Three-dimensional ordered titanium dioxide-zirconium dioxide film-based microfluidic device for efficient on-chip phosphopeptide enrichment.

    Science.gov (United States)

    Zhao, De; He, Zhongyuan; Wang, Gang; Wang, Hongzhi; Zhang, Qinghong; Li, Yaogang

    2016-09-15

    Microfluidic technology plays a significant role in separating biomolecules, because of its miniaturization, integration, and automation. Introducing micro/nanostructured functional materials can improve the properties of microfluidic devices, and extend their application. Inverse opal has a three-dimensional ordered net-like structure. It possesses a large surface area and exhibits good mass transport, making it a good candidate for bio-separation. This study exploits inverse opal titanium dioxide-zirconium dioxide films for on-chip phosphopeptide enrichment. Titanium dioxide-zirconium dioxide inverse opal film-based microfluidic devices were constructed from templates of 270-, 340-, and 370-nm-diameter poly(methylmethacrylate) spheres. The phosphopeptide enrichments of these devices were determined by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. The device constructed from the 270-nm-diameter sphere template exhibited good comprehensive phosphopeptide enrichment, and was the best among these three devices. Because the size of opal template used in construction was the smallest, the inverse opal film therefore had the smallest pore sizes and the largest surface area. Enrichment by this device was also better than those of similar devices based on nanoparticle films and single component films. The titanium dioxide-zirconium dioxide inverse opal film-based device provides a promising approach for the efficient separation of various biomolecules. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Improved Light Extraction Efficiency by Photonic Crystal Arrays on Transparent Contact Layer Using Focused Ion Beams

    International Nuclear Information System (INIS)

    Wu, G.M.; Tsai, B.H.; Kung, S.F.; Wu, C.F.

    2011-01-01

    Nitride-based thin-film materials have become increasingly important for the high brightness light-emitting diode applications. The improvements in light extraction and lower power consumption are highly desired. Although the internal quantum efficiency of GaN-based LED has been relatively high, only a small fraction of light can be extracted. In this study, a new design of two-dimensional photonic crystal array has been prepared on the top transparent contact layer of indium-tin oxide film to improve the light extraction efficiency using focused ion beam. The acceleration voltage of the Ga dual-beam nanotechnology system SMI 3050 was 30 kV and the ion beam current was 100 pA. The cylindrical air holes had the diameter of 150 nm and depth of 100 nm. The micro photoluminescence analysis results showed that the light output intensity could be 1.5 times of that of the non-patterned control sample. In addition, the structural damage from the focused ion beam drilling of GaN step could be eliminated. The excellent I-V characteristics have been maintained, and the external light extraction efficiency would be still improved for the LED devices. (author)

  12. Highway-runoff quality, and treatment efficiencies of a hydrodynamic-settling device and a stormwater-filtration device in Milwaukee, Wisconsin

    Science.gov (United States)

    Horwatich, Judy A.; Bannerman, Roger T.; Pearson, Robert

    2011-01-01

    The treatment efficiencies of two prefabricated stormwater-treatment devices were tested at a freeway site in a high-density urban part of Milwaukee, Wisconsin. One treatment device is categorized as a hydrodynamic-settling device (HSD), which removes pollutants by sedimentation and flotation. The other treatment device is categorized as a stormwater-filtration device (SFD), which removes pollutants by filtration and sedimentation. During runoff events, flow measurements were recorded and water-quality samples were collected at the inlet and outlet of each device. Efficiency-ratio and summation-of-load (SOL) calculations were used to estimate the treatment efficiency of each device. Event-mean concentrations and loads that were decreased by passing through the HSD include total suspended solids (TSS), suspended sediment (SS), total phosphorus (TP), total copper (TCu), and total zinc (TZn). The efficiency ratios for these constituents were 42, 57, 17, 33, and 23 percent, respectively. The SOL removal rates for these constituents were 25, 49, 10, 27, and 16 percent, respectively. Event-mean concentrations and loads that increased by passing through the HSD include chloride (Cl), total dissolved solids (TDS), and dissolved zinc (DZn). The efficiency ratios for these constituents were -347, -177, and 20 percent, respectively. Four constituents—dissolved phosphorus (DP), chemical oxygen demand (COD), total polycyclic aromatic hydrocarbon (PAH), and dissolved copper (DCu)—are not included in the list of computed efficiency ratio and SOL because the variability between sampled inlet and outlet pairs were not significantly different. Event-mean concentrations and loads that decreased by passing through the SFD include TSS, SS, TP, DCu, TCu, DZn, TZn, and COD. The efficiency ratios for these constituents were 59, 90, 40, 21, 66, 23, 66, and 18, respectively. The SOLs for these constituents were 50, 89, 37, 19, 60, 20, 65, and 21, respectively. Two constituents—DP and

  13. Evaluation of economic efficiency of process improvement in food packaging

    Directory of Open Access Journals (Sweden)

    Jana Hron

    2012-01-01

    Full Text Available In general, we make gains in process by the three fundamental ways. First, we define or redefine our process in a strategic sense. Second, once defined or redefined, we commence process operations and use process control methods to target and stabilize our process. Third, we use process improvement methods, as described in this paper, along with process control to fully exploit our process management and/or technology. Process improvement is focused primarily in our subprocesses and sub-subprocesses. Process leverage is the key to process improvement initiatives. This means that small improvements of the basic manufacturing operations can have (with the assumption of mass repetition of the operation a big impact on the functioning of the whole production unit. The complexity within even small organizations, in people, products, and processes, creates significant challenges in effectively and efficiently using these initiatives tools. In this paper we are going to place process purposes in the foreground and initiatives and tools in the background as facilitator to help accomplish process purpose. Initiatives and tools are not the ends we are seeking; result/outcomes in physical, economics, timeliness, and customer service performance matter. In the paper process boundaries (in a generic sense are set by our process purpose and our process definition. Process improvement is initiated within our existing process boundaries. For example, in a fast-food restaurant, if we define our cooking process around a frying technology, then we provide process improvements within our frying technology. On the other hand, if we are considering changing to a broiling technology, then we are likely faced with extensive change, impacting our external customers, and a process redefinition may be required. The result / aim of the paper are based on the example of the process improving of a food packaging quality. Specifically, the integration of two approaches

  14. Leanergy(TM): how lean manufacturing can improve energy efficiency.

    Science.gov (United States)

    Riche, Jean-Pierre

    2013-01-01

    Energy efficiency has become a competitive issue for industrial companies. The evolution of energy prices and regulation will make this issue even more important in the future. For several years, the energy-intensive chemical industry has been implementing corrective actions. Helped by the absorption of base load energy consumption by larger production volumes, specific energy consumption (KWh per production unit) has been significantly reduced in recent years. However, most plants have reached the end of their first action plan based on improving the utilities performance. The Leanergy(TM) method developed by the consultancy company Okavango-energy, is a structured approach based on lean manufacturing which widens the scope of saving sources to process and operations. Starting from the analysis of actual production requirements, Okavango is able to adjust consumption to minimum requirements and so remove any energy consumption that does not contribute to the added value creation.

  15. Renewable energy: An efficient mechanism to improve GDP

    International Nuclear Information System (INIS)

    Chien Taichen; Hu Jinli

    2008-01-01

    This article analyzes the effects of renewable energy on GDP for 116 economies in 2003 through Structural Equation Modeling (SEM) approach. In order to decipher the mechanism of how the use of renewables improves macroeconomic efficiency, we decompose GDP by the 'expenditure approach'. Although previous theory predicts positive effects of renewables on capital formation and trade balance, the SEM results show that renewables have a significant positive influence on capital formation only. The result that renewables do not have a significant impact on trade balance implies that renewables do not have an import substitution effect. Thus, we confirm the positive relationship between renewable energy and GDP through the path of increasing capital formation, but not for the path of increasing trade balance

  16. Challenges in biobutanol production: How to improve the efficiency?

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Veronica; Paekkilae, Johanna; Muurinen, Esa; Keiski, Riitta L. [Mass and Heat Transfer Process Laboratory, Department of Process and Environmental Engineering, POB 4300, FI-90014 University of Oulu, Oulu (Finland); Ojamo, Heikki [Bioprocess Engineering Laboratory, Department of Process and Environmental Engineering, POB 4300, FI-90014 University of Oulu, Oulu (Finland)

    2011-02-15

    There is an increasing interest in the production of chemicals and fuels from renewable resources due to the continuing price increase of fossil resources, the insecurity of the availability of fossil resources in the future, and additionally environmental concerns and legislations. Biobutanol may be produced by the acetone-butanol-ethanol (ABE) fermentation. This paper reviews the biobutanol production bringing up the problems and challenges to overcome. The aim of the paper is to help in finding opportunities to make the process feasible in the near future. The analysis stresses the idea of improving the efficiency of the fermentation stage by altering the up (pretreatment of the raw material) and downstream (product recovery and purification) processes. The paper also explores the biobutanol production from the biorefinery perspective. Finally the review brings up the important role of research in developing and implementing the production of biobutanol by the ABE fermentation. (author)

  17. Challenges in biobutanol production: How to improve the efficiency?

    International Nuclear Information System (INIS)

    Garcia, Veronica; Paekkilae, Johanna; Muurinen, Esa; Keiski, Riitta L.; Ojamo, Heikki

    2011-01-01

    There is an increasing interest in the production of chemicals and fuels from renewable resources due to the continuing price increase of fossil resources, the insecurity of the availability of fossil resources in the future, and additionally environmental concerns and legislations. Biobutanol may be produced by the acetone-butanol-ethanol (ABE) fermentation. This paper reviews the biobutanol production bringing up the problems and challenges to overcome. The aim of the paper is to help in finding opportunities to make the process feasible in the near future. The analysis stresses the idea of improving the efficiency of the fermentation stage by altering the up (pretreatment of the raw material) and downstream (product recovery and purification) processes. The paper also explores the biobutanol production from the biorefinery perspective. Finally the review brings up the important role of research in developing and implementing the production of biobutanol by the ABE fermentation. (author)

  18. Improving robustness and computational efficiency using modern C++

    International Nuclear Information System (INIS)

    Paterno, M; Kowalkowski, J; Green, C

    2014-01-01

    For nearly two decades, the C++ programming language has been the dominant programming language for experimental HEP. The publication of ISO/IEC 14882:2011, the current version of the international standard for the C++ programming language, makes available a variety of language and library facilities for improving the robustness, expressiveness, and computational efficiency of C++ code. However, much of the C++ written by the experimental HEP community does not take advantage of the features of the language to obtain these benefits, either due to lack of familiarity with these features or concern that these features must somehow be computationally inefficient. In this paper, we address some of the features of modern C+-+, and show how they can be used to make programs that are both robust and computationally efficient. We compare and contrast simple yet realistic examples of some common implementation patterns in C, currently-typical C++, and modern C++, and show (when necessary, down to the level of generated assembly language code) the quality of the executable code produced by recent C++ compilers, with the aim of allowing the HEP community to make informed decisions on the costs and benefits of the use of modern C++.

  19. Improvement of powertrain efficiency through energy breakdown analysis

    International Nuclear Information System (INIS)

    Damiani, Lorenzo; Repetto, Matteo; Prato, Alessandro Pini

    2014-01-01

    Highlights: • Energy breakdown analysis for the vehicular powertrain. • Model for road vehicles simulation in different missions. • Implemented powertrain management strategies: intelligent gearbox, Stop and Start, free wheel. • Innovative hybrid powertrain turned to engine thermodynamic cycles minimization. • Evaluation of fuel savings associated to each management strategy. - Abstract: A vehicular powertrain can be thought as an energy conversion chain, each component being characterized by its efficiency. Significant global efficiency improvements can be achieved once is identified the system energy breakdown, individuating the losses connected to each powertrain component; it is then possible to carry out the most appropriate interventions. This paper presents a simulation study of a diesel-fuelled commercial vehicle powertrain based on the above summarized point of view. The work aims at individuating the energy flows involved in the system during different missions, proposing an intelligent combination of technical solutions which minimize fuel consumption. Through a validated Matlab–Simulink model, able to indicate the powertrain energy breakdown, simulations are carried out to evaluate the fuel saving associated to a series of powertrain management logics which lead to the minimization of engine losses, the recovery of reverse power in deceleration and braking, the elimination of useless engine cycles. Tests were performed for different real missions (urban, extra-urban and highway). The results obtained point out a –23% fuel consumption (average value for urban, extra-urban and highway missions) compared to the traditional powertrain. Clearly, such result affects positively the CO 2 emission

  20. Improving Remote Species Identification through Efficient Training Data Collection

    Directory of Open Access Journals (Sweden)

    Claire A. Baldeck

    2014-03-01

    Full Text Available Plant species identification and mapping based on remotely-sensed spectral signatures is a challenging task with the potential to contribute enormously to ecological studies. Success in this task rests upon the appropriate collection and use of costly field-based training data, and researchers are in need of ways to improve collection efficiency based on quantitative evidence. Using imaging spectrometer data collected by the Carnegie Airborne Observatory for hundreds of field-identified tree crowns in Kruger National Park, South Africa, we developed woody plant species classification models and evaluated how classification accuracy increases with increasing numbers of training crowns. First, we show that classification accuracy must be estimated while respecting the crown as the basic unit of data; otherwise, accuracy will be overestimated and the amount of training data needed to perform successful classification will be underestimated. We found that classification accuracy and the number of training crowns needed to perform successful classification varied depending on the number and spectral separability of species in the model. We also used a modified Michaelis-Menten function to describe the empirical relationship between training crowns and model accuracy, and show how this function may be useful for predicting accuracy. This framework can assist researchers in designing field campaigns to maximize the efficiency of field data collection, and thus the amount of biodiversity information gained from remote species identification models.

  1. Improve photocurrent quantum efficiency of carbon nanotube by chemical treatment

    International Nuclear Information System (INIS)

    Wang Hongguang; Wei Jinquan; Jia Yi; Li Zhen; Zhu Hongwei; Wang Kunlin; Wu Dehai

    2012-01-01

    Highlights: ► The QE of photocurrent for the H 2 O 2 -treated CNTs reaches to 5.28% at U bias = 0.1 V. ► Moderate chemical treatment can enhance the QE of photocurrent of CNTs. ► Excessive chemical treatment decreases the photocurrent quantum efficiency of CNTs. - Abstract: High photocurrent quantum efficiency (QE) of carbon nanotubes (CNTs) is important to their photovoltaic applications. The ability of photocurrent generation of CNTs depends on their band structure and surface state. For given CNTs, it is possible to improve the QE of photocurrent by chemical modification. Here, we study the effects of simple chemical treatment on the QE of CNTs by measuring the photocurrent of macroscopic CNT bundles. The QE of the H 2 O 2 -treated CNT bundle reaches 5.28% at 0.1 V bias voltage at a laser (λ = 473 nm) illumination, which is 85% higher than that of the pristine sample. But the QE of the CNTs treated in concentrated HNO 3 is lower than that of the pristine sample. It shows that moderate chemical treatment can enhance the photocurrent QE and excessive chemical treatment will decrease the QE because of introducing lots of structural defects.

  2. Improving labeling efficiency in automatic quality control of MRSI data.

    Science.gov (United States)

    Pedrosa de Barros, Nuno; McKinley, Richard; Wiest, Roland; Slotboom, Johannes

    2017-12-01

    To improve the efficiency of the labeling task in automatic quality control of MR spectroscopy imaging data. 28'432 short and long echo time (TE) spectra (1.5 tesla; point resolved spectroscopy (PRESS); repetition time (TR)= 1,500 ms) from 18 different brain tumor patients were labeled by two experts as either accept or reject, depending on their quality. For each spectrum, 47 signal features were extracted. The data was then used to run several simulations and test an active learning approach using uncertainty sampling. The performance of the classifiers was evaluated as a function of the number of patients in the training set, number of spectra in the training set, and a parameter α used to control the level of classification uncertainty required for a new spectrum to be selected for labeling. The results showed that the proposed strategy allows reductions of up to 72.97% for short TE and 62.09% for long TE in the amount of data that needs to be labeled, without significant impact in classification accuracy. Further reductions are possible with significant but minimal impact in performance. Active learning using uncertainty sampling is an effective way to increase the labeling efficiency for training automatic quality control classifiers. Magn Reson Med 78:2399-2405, 2017. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  3. Improving the energy efficiency of industrial refrigeration systems

    International Nuclear Information System (INIS)

    Oh, Jin-Sik; Binns, Michael; Park, Sangmin; Kim, Jin-Kuk

    2016-01-01

    Various retrofit design options are available for improving the energy efficiency and economics of industrial refrigeration systems. This study considers a novel retrofit option using a mixed refrigerant (MR) in refrigeration cycles designed for use with a pure refrigerant (PR). In this way energy savings can be realized by switching refrigerants without requiring extensive and expensive reconfiguration of equipment. Hence, the aim here is to test the common thinking that equipment should always be extensively reconfigured when switching from pure to mixed refrigerants. To determine the most energy-efficient operating conditions for each refrigeration design an optimization framework is utilized linking a process simulator with an external optimization method. A case study is presented to demonstrate how the proposed process modeling and optimization framework can be applied and to illustrate the economic benefits of using the retrofit design options considered here. For the case considered in this paper, savings of shaft power required for the refrigeration cycle can be achieved from 16.3% to 27.2% when the pure refrigerant is replaced with mixed refrigerants and operating conditions are re-optimized. - Highlights: • Design methods for the design of refrigeration cycles in retrofit cases. • Consideration of mixed refrigerants to the existing multi-level pure-refrigerant cycles. • Optimization of refrigeration cycles with integrated use of a process simulator with an optimizer.

  4. High Efficiency Three-phase Power Factor Correction Rectifier using Wide Band-Gap Devices

    DEFF Research Database (Denmark)

    Kouchaki, Alireza

    Improving the conversion efficiency of power factor correction (PFC) rectifiers has become compelling due to their wide applications such as adjustable speed drives, uninterruptible power supplies (UPS), and battery chargers for electric vehicles (EVs). The attention to PFCs has increased even more....... Therefore, current controllers are also important to be investigated in this project. In this PhD research work, a comprehensive design of a two-level three-phase PFC rectifier using silicon-carbide (SiC) switches to achieve high efficiency is presented. The work is divided into two main parts: 1) Optimum...

  5. Improved vascularization of planar membrane diffusion devices following continuous infusion of vascular endothelial growth factor.

    Science.gov (United States)

    Trivedi, N; Steil, G M; Colton, C K; Bonner-Weir, S; Weir, G C

    2000-01-01

    Improving blood vessel formation around an immunobarrier device should improve the survival of the encapsulated tissue. In the present study we investigated the formation of new blood vessels around a planar membrane diffusion device (the Baxter Theracyte System) undergoing a continuous infusion of vascular endothelial growth factor through the membranes and into the surrounding tissue. Each device (20 microl) had both an inner immunoisolation membrane and an outer vascularizing membrane. Human recombinant vascular endothelial growth factor-165 was infused at 100 ng/day (low dose: n = 6) and 500 ng/day (high dose: n = 7) for 10 days into devices implanted s.c. in Sprague-Dawley rats; noninfused devices transplanted for an identical period were used as controls (n = 5). Two days following the termination of VEGF infusion, devices were loaded with 20 microl of Lispro insulin (1 U/kg) and the kinetics of insulin release from the lumen of the device was assessed. Devices were then explanted and the number of blood vessels (capillary and noncapillary) was quantified using morphometry. High-dose vascular endothelial growth factor infusion resulted in two- to threefold more blood vessels around the device than that obtained with the noninfused devices and devices infused with low-dose vascular endothelial growth factor. This increase in the number of blood vessels was accompanied by a modest increase in insulin diffusion from the device in the high-dose vascular endothelial growth factor infusion group. We conclude that vascular endothelial growth factor can be used to improve blood vessel formation adjacent to planar membrane diffusion devices.

  6. CSA: An efficient algorithm to improve circular DNA multiple alignment

    Directory of Open Access Journals (Sweden)

    Pereira Luísa

    2009-07-01

    Full Text Available Abstract Background The comparison of homologous sequences from different species is an essential approach to reconstruct the evolutionary history of species and of the genes they harbour in their genomes. Several complete mitochondrial and nuclear genomes are now available, increasing the importance of using multiple sequence alignment algorithms in comparative genomics. MtDNA has long been used in phylogenetic analysis and errors in the alignments can lead to errors in the interpretation of evolutionary information. Although a large number of multiple sequence alignment algorithms have been proposed to date, they all deal with linear DNA and cannot handle directly circular DNA. Researchers interested in aligning circular DNA sequences must first rotate them to the "right" place using an essentially manual process, before they can use multiple sequence alignment tools. Results In this paper we propose an efficient algorithm that identifies the most interesting region to cut circular genomes in order to improve phylogenetic analysis when using standard multiple sequence alignment algorithms. This algorithm identifies the largest chain of non-repeated longest subsequences common to a set of circular mitochondrial DNA sequences. All the sequences are then rotated and made linear for multiple alignment purposes. To evaluate the effectiveness of this new tool, three different sets of mitochondrial DNA sequences were considered. Other tests considering randomly rotated sequences were also performed. The software package Arlequin was used to evaluate the standard genetic measures of the alignments obtained with and without the use of the CSA algorithm with two well known multiple alignment algorithms, the CLUSTALW and the MAVID tools, and also the visualization tool SinicView. Conclusion The results show that a circularization and rotation pre-processing step significantly improves the efficiency of public available multiple sequence alignment

  7. Rapeseed is an efficient energy crop which can still improve

    Directory of Open Access Journals (Sweden)

    Flenet Francis

    2007-11-01

    Full Text Available The ability of biofuels to contribute efficiently to the replacement of fossil energy and to the reduction of greenhouse gas emissions has been a matter of debate. Hence, there is a need to assess accurately the energy balance of biofuels and their ability to reduce greenhouse gas emissions, in order to evaluate and to improve the benefit for society. In rapeseed, the energy ratio (energy produced per unit of non-renewable energy input is well above 2 whatever the method of calculation. In order to investigate the variability of energy ratios and to identify ways of improvement, a study was conducted in France in 2005 and 2006. The method of mass allocation of input energy was used for calculations, instead of the substitution method, because with this method the results do not depend on the utilization of co-products. Hence, this method is better adapted to follow improvements. A great variability in the energy ratio was observed in 2005 and 2006. Seed yields and energy cost of fertilizer N explained most of this variability. Hence, improvements should focus on increasing yield with little increase in energy cost, and on decreasing wasting of N fertilizer. However the farmer incomes, and the net production of energy per hectare, must also be a matter of concern. The inventories of greenhouse gas emissions of biofuels are still uncertain because of the great variability of soil emissions, due to environmental and management factors. Hence, in order to assess the effect of rapeseed on greenhouse gas emissions, methods based on process-oriented models accounting for these factors must be used. Such models give promising results, but further testing is still needed.

  8. Energy-Efficient Real-Time Human Activity Recognition on Smart Mobile Devices

    Directory of Open Access Journals (Sweden)

    Jin Lee

    2016-01-01

    Full Text Available Nowadays, human activity recognition (HAR plays an important role in wellness-care and context-aware systems. Human activities can be recognized in real-time by using sensory data collected from various sensors built in smart mobile devices. Recent studies have focused on HAR that is solely based on triaxial accelerometers, which is the most energy-efficient approach. However, such HAR approaches are still energy-inefficient because the accelerometer is required to run without stopping so that the physical activity of a user can be recognized in real-time. In this paper, we propose a novel approach for HAR process that controls the activity recognition duration for energy-efficient HAR. We investigated the impact of varying the acceleration-sampling frequency and window size for HAR by using the variable activity recognition duration (VARD strategy. We implemented our approach by using an Android platform and evaluated its performance in terms of energy efficiency and accuracy. The experimental results showed that our approach reduced energy consumption by a minimum of about 44.23% and maximum of about 78.85% compared to conventional HAR without sacrificing accuracy.

  9. Efficiency improvement of technological preparation of power equipment manufacturing

    Science.gov (United States)

    Milukov, I. A.; Rogalev, A. N.; Sokolov, V. P.; Shevchenko, I. V.

    2017-11-01

    Competitiveness of power equipment primarily depends on speeding-up the development and mastering of new equipment samples and technologies, enhancement of organisation and management of design, manufacturing and operation. Actual political, technological and economic conditions cause the acute need in changing the strategy and tactics of process planning. At that the issues of maintenance of equipment with simultaneous improvement of its efficiency and compatibility to domestically produced components are considering. In order to solve these problems, using the systems of computer-aided process planning for process design at all stages of power equipment life cycle is economically viable. Computer-aided process planning is developed for the purpose of improvement of process planning by using mathematical methods and optimisation of design and management processes on the basis of CALS technologies, which allows for simultaneous process design, process planning organisation and management based on mathematical and physical modelling of interrelated design objects and production system. An integration of computer-aided systems providing the interaction of informative and material processes at all stages of product life cycle is proposed as effective solution to the challenges in new equipment design and process planning.

  10. Efficiency improvement of flat plate solar collector using reflector

    Directory of Open Access Journals (Sweden)

    Himangshu Bhowmik

    2017-11-01

    Full Text Available Solar collectors are the main components of a solar heating system. The collectors collect the sun’s energy, transform this radiation into heat, and then transfer this heat into a fluid, water or air, which has many household or industrial applications. This paper introduces a new technology to improve the performance of the solar thermal collectors. The solar reflector used here with the solar collector to increase the reflectivity of the collector. Thus, the reflector concentrates both direct and diffuse radiation of the sun toward the collector. To maximize the intensity of incident radiation, the reflector was allowed to change its angle with daytime. The radiations coming from the sun’s energy were converted into heat, and then this heat was transferred to the collector fluid, water. A prototype of a solar water heating system was constructed and obtained the improvement of the collector efficiency around 10% by using the reflector. Thus, the present solar water heating systems having the best thermal performance compared to the available systems.

  11. Modified Dirac Hamiltonian for efficient quantum mechanical simulations of micron sized devices

    Energy Technology Data Exchange (ETDEWEB)

    Habib, K. M. Masum, E-mail: masum.habib@virginia.edu; Ghosh, Avik W. [Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States); Sajjad, Redwan N. [Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2016-03-14

    Representing massless Dirac fermions on a spatial lattice poses a potential challenge known as the Fermion Doubling problem. Addition of a quadratic term to the Dirac Hamiltonian provides a possible way to circumvent this problem. We show that the modified Hamiltonian with the additional term results in a very small Hamiltonian matrix when discretized on a real space square lattice. The resulting Hamiltonian matrix is considerably more efficient for numerical simulations without sacrificing on accuracy and is several orders of magnitude faster than the atomistic tight binding model. Using this Hamiltonian and the non-equilibrium Green's function formalism, we show several transport phenomena in graphene, such as magnetic focusing, chiral tunneling in the ballistic limit, and conductivity in the diffusive limit in micron sized graphene devices. The modified Hamiltonian can be used for any system with massless Dirac fermions such as Topological Insulators, opening up a simulation domain that is not readily accessible otherwise.

  12. Study of organic light emitting devices (OLEDs) with optimal emission efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Jai [School of Engineering and IT, B-purple 12, Faculty of EHS, Charles Darwin University, Darwin, NT 0909 (Australia)

    2010-04-15

    The external emission efficiency of organic light emitting devices (OLEDs) is analysed by studying the rate of spontaneous emission of both singlet and triplet excitons and their corresponding radiative lifetimes. Rates of spontaneous emissions are calculated from the first order perturbation theory using the newly discovered time-dependent spin-orbit-exciton-photon interaction operator as the perturbation operator. It is clearly shown how the new interaction operator is responsible for attracting triplet excitons to a phosphor (heavy metal atom) and then it flips the spins to a singlet configuration. Thus, the spin forbidden transition becomes spin allowed. Calculated rates agree with the experimental results qualitatively. Results are of general interests for OLED studies. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  13. Modified Dirac Hamiltonian for efficient quantum mechanical simulations of micron sized devices

    International Nuclear Information System (INIS)

    Habib, K. M. Masum; Ghosh, Avik W.; Sajjad, Redwan N.

    2016-01-01

    Representing massless Dirac fermions on a spatial lattice poses a potential challenge known as the Fermion Doubling problem. Addition of a quadratic term to the Dirac Hamiltonian provides a possible way to circumvent this problem. We show that the modified Hamiltonian with the additional term results in a very small Hamiltonian matrix when discretized on a real space square lattice. The resulting Hamiltonian matrix is considerably more efficient for numerical simulations without sacrificing on accuracy and is several orders of magnitude faster than the atomistic tight binding model. Using this Hamiltonian and the non-equilibrium Green's function formalism, we show several transport phenomena in graphene, such as magnetic focusing, chiral tunneling in the ballistic limit, and conductivity in the diffusive limit in micron sized graphene devices. The modified Hamiltonian can be used for any system with massless Dirac fermions such as Topological Insulators, opening up a simulation domain that is not readily accessible otherwise.

  14. Experimental study of elementary collection efficiency of aerosols by spray: Design of the experimental device

    Energy Technology Data Exchange (ETDEWEB)

    Ducret, D.; Vendel, J.; Garrec. S.L.

    1995-02-01

    The safety of a nuclear power plant containment building, in which pressure and temperature could increase because of a overheating reactor accident, can be achieved by spraying water drops. The spray reduces the pressure and the temperature levels by condensation of steam on cold water drops. The more stringent thermodynamic conditions are a pressure of 5.10{sup 5} Pa (due to steam emission) and a temperature of 413 K. Moreover its energy dissipation function, the spray leads to the washout of fission product particles emitted in the reactor building atmosphere. The present study includes a large program devoted to the evaluation of realistic washout rates. The aim of this work is to develop experiments in order to determine the collection efficiency of aerosols by a single drop. To do this, the experimental device has to be designed with fundamental criteria:-Thermodynamic conditions have to be representative of post-accident atmosphere. Thermodynamic equilibrium has to be attained between the water drops and the gaseous phase. Thermophoretic, diffusiophoretic and mechanical effects have to be studied independently. Operating conditions have to be homogenous and constant during each experiment. This paper presents the design of the experimental device. In practice, the consequences on the design of each of the criteria given previously and the necessity of being representative of the real conditions will be described.

  15. Study on collection efficiency of fission products by spray: Experimental device and modelling

    Energy Technology Data Exchange (ETDEWEB)

    Ducret, D.; Roblot, D.; Vendel, J. [Institut de Protection et de Surete Nucleaire, Gif-Sur-Yvette (France); Billarand, Y. [ECCO Pharmacie et Chimie, Neuilly (France)

    1997-08-01

    Consequences of an hypothetical overheating reactor accident in nuclear power plants can be limited by spraying cold water drops into containment building. The spray reduces the pressure and the temperature levels by condensation of steam and leads to the washout of fission products (aerosols and gaseous iodine). The present study includes a large program devoted to the evaluation of realistic washout rates. An experimental device (named CARAIDAS) was designed and built in order to determine the collection efficiency of aerosols and iodine absorption by drops with representative conditions of post-accident atmosphere. This experimental device is presented in the paper and more particularly: (1) the experimental enclosure in which representative thermodynamic conditions can be achieved, (2) the monosized drops generator, the drops diameter measurement and the drops collector, (3) the cesium iodide aerosols generator and the aerosols measurements. Modelling of steam condensation on drops aerosols collection and iodine absorption are described. First experimental and code results on drops and aerosols behaviour are compared. 8 refs., 18 figs.

  16. Berkeley Lab Sheds Light on Improving Solar Cell Efficiency

    International Nuclear Information System (INIS)

    Lawrence Berkeley National Laboratory

    2007-01-01

    Typical manufacturing methods produce solar cells with an efficiency of 12-15%; and 14% efficiency is the bare minimum for achieving a profit. In work performed at the Ernest Orlando Lawrence Berkeley National Laboratory (Berkeley, CA, 5 10-486-577 1)--a US Department of Energy national laboratory that conducts unclassified scientific research and is managed by the University of California--scientist Scott McHugo has obtained keen insights into the impaired performance of solar cells manufactured from polycrystalline silicon. The solar cell market is potentially vast, according to Berkeley Lab. Lightweight solar panels are highly beneficial for providing electrical power to remote locations in developing nations, since there is no need to build transmission lines or truck-in generator fuel. Moreover, industrial nations confronted with diminishing resources have active programs aimed at producing improved, less expensive solar cells. 'In a solar cell, there is a junction between p-type silicon and an n-type layer, such as diffused-in phosphorous', explained McHugo, who is now with Berkeley Lab's Accelerator and Fusion Research Division. 'When sunlight is absorbed, it frees electrons, which start migrating in a random-walk fashion toward that junction. If the electrons make it to the junction; they contribute to the cell's output of electric current. Often, however, before they reach the junction, they recombine at specific sites in the crystal' (and, therefore, cannot contribute to current output). McHugo scrutinized a map of a silicon wafer in which sites of high recombination appeared as dark regions. Previously, researchers had shown that such phenomena occurred not primarily at grain boundaries in the polycrystalline material, as might be expected, but more often at dislocations in the crystal. However, the dislocations themselves were not the problem. Using a unique heat treatment technique, McHugo performed electrical measurements to investigate the material

  17. Improving efficiency and reducing administrative burden through electronic communication.

    Science.gov (United States)

    Cook, Katlyn E; Ludens, Gail M; Ghosh, Amit K; Mundell, William C; Fleming, Kevin C; Majka, Andrew J

    2013-01-01

    The InBox messaging system is an internal, electronic program used at Mayo Clinic, Rochester, MN, to facilitate the sending, receiving, and answering of patient-specific messages and alerts. A standardized InBox was implemented in the Division of General Internal Medicine to decrease the time physicians, physician assistants, and nurse practitioners (clinicians) spend on administrative tasks and to increase efficiency. Clinicians completed surveys and a preintervention InBox pilot test to determine inefficiencies related to administrative burdens and defects (message entry errors). Results were analyzed using Pareto diagrams, value stream mapping, and root cause analysis to prioritize administrative-burden inefficiencies to develop a new, standardized InBox. Clinicians and allied health staff were the target of this intervention and received standardized InBox training followed by a postintervention pilot test for clinicians. Sixteen of 28 individuals (57%) completed the preintervention survey. Twenty-eight clinicians participated in 2 separate 8-day pilot tests (before and after intervention) for the standardized InBox. The number of InBox defects was substantially reduced from 37 (Pilot 1) to 7 (Pilot 2). Frequent InBox defects decreased from 25% to 10%. More than half of clinicians believed the standardized InBox positively affected their work, and 100% of clinicians reported no negative affect on their work. This project demonstrated the successful implementation of the standardized InBox messaging system. Initial assessments show substantial reduction of InBox entry defects and administrative tasks completed by clinicians. The findings of this project suggest increased clinician and allied health staff efficiency, satisfaction, improved clinician work-life balance, and decreased clinician burden caused by administrative tasks.

  18. A model to improve efficiency and effectiveness of safeguards measures

    International Nuclear Information System (INIS)

    D'Amato, Eduardo; Llacer, Carlos; Vicens, Hugo

    2001-01-01

    Full text: The main purpose of our current studies is to analyse the measures to be adopted tending to integrate the traditional safeguard measures to the ones stated in the Additional Protocol (AP). A simplified nuclear fuel cycle model is considered to draw some conclusions on the application of integrated safeguard measures. This paper includes a briefing, describing the historical review that gave birth to the A.P. and proposes a model to help the control bodies in the making decision process. In May 1997, the Board of Governors approved the Model Additional Protocol (MAP) which aimed at strengthening the effectiveness and improving the efficiency of safeguard measures. For States under a comprehensive safeguard agreement the measures adopted provide credible assurance on the absence of undeclared nuclear material and activities. In September 1999, the governments of Argentina and Brazil formally announced in the Board of Governors that both countries would start preliminary consultations on one adapted MAP applied to the Agreement between the Republic of Argentina, the Federative Republic of Brazil, the Brazilian-Argentine Agency for Accounting and Control of Nuclear Materials and the International Atomic Energy Agency for the Application of Safeguards (Quatripartite Agreement/INFCIRC 435). In December 1999, a first draft of the above mentioned document was provided as a starting point of discussion. During the year 2000 some modifications to the original draft took place. These were the initial steps in the process aiming at reaching the adequate conditions to adhere to the A.P. in each country in a future Having in mind the future AP implementation, the safeguards officers of the Regulatory Body of Argentina (ARN) began to think about the future simultaneous application of the two types of safeguards measures, the traditional and the non traditional ones, what should converge in an integrated system. By traditional safeguards it is understood quantitative

  19. The X-ARAPUCA: an improvement of the ARAPUCA device

    Science.gov (United States)

    Machado, A. A.; Segreto, E.; Warner, D.; Fauth, A.; Gelli, B.; Máximo, R.; Pissolatti, A.; Paulucci, L.; Marinho, F.

    2018-04-01

    The ARAPUCA is a novel technology for the detection of liquid argon scintillation light, which has been proposed for the far detector of the Deep Underground Neutrino Experiment. The X-ARAPUCA is an improvement to the original ARAPUCA design, retaining the original ARAPUCA concept of photon trapping inside a highly reflective box while using a wavelength shifting slab inside the box to increase the probability of collecting trapped photons onto a silicon photomultiplier array. The X-ARAPUCA concept is presented and its performances are compared to those of a standard ARAPUCA by means of analytical calculations and Monte Carlo simulations.

  20. Three-Dimensional Hetero-Integration of Faceted GaN on Si Pillars for Efficient Light Energy Conversion Devices.

    Science.gov (United States)

    Kim, Dong Rip; Lee, Chi Hwan; Cho, In Sun; Jang, Hanmin; Jeon, Min Soo; Zheng, Xiaolin

    2017-07-25

    An important pathway for cost-effective light energy conversion devices, such as solar cells and light emitting diodes, is to integrate III-V (e.g., GaN) materials on Si substrates. Such integration first necessitates growth of high crystalline III-V materials on Si, which has been the focus of many studies. However, the integration also requires that the final III-V/Si structure has a high light energy conversion efficiency. To accomplish these twin goals, we use single-crystalline microsized Si pillars as a seed layer to first grow faceted Si structures, which are then used for the heteroepitaxial growth of faceted GaN films. These faceted GaN films on Si have high crystallinity, and their threading dislocation density is similar to that of GaN grown on sapphire. In addition, the final faceted GaN/Si structure has great light absorption and extraction characteristics, leading to improved performance for GaN-on-Si light energy conversion devices.

  1. Recombination region improvement for reduced efficiency roll-off in phosphorescent OLEDs with dual emissive layers

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Zhu; Zhou, Shunliang [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054 (China); Hu, Song [Chengdu Institute of Optics and Electronics, Chinese Academy of Sciences, Chengdu 610209 (China); Yu, Junsheng, E-mail: jsyu@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054 (China)

    2014-10-15

    High-performance phosphorescent organic light-emitting diodes (PhOLEDs) by using dual-emissive-layer (DEL) structure to reduce efficiency roll-off were fabricated. The DEL was comprised of a hole-transport-type host of N, N′-bis(naphthalen-1-yl)-N, N′-bis(phenyl)-benzidine (NPB) and a bipolar host of 4,4′-bis(carbazol-9-yl)biphenyl (CBP), which were both doped with an orange phosphorescent dopant of bis[2-(4-tert-butylphenyl)-benzothiazolato-N,C2′]iridium (acetylacetonate) [(t-bt){sub 2}Ir(acac)]. After the optimization of doping concentration of the first emissive layer (FEL), the device with DEL exhibited 11% lower roll-off power efficiency than single emissive layer devices (SED) when the luminance increased from 1000 cd/m{sup 2} to 10,000 cd/m{sup 2}. The hole–electron recombination zone in DEL was illuminated by inserting an ultrathin fluorescent probe of 4-(dicyanomethylene)-2-tert-butyl-6 (1,1,7,7-tetramethyljulolidin-4-yl-vinyl)-4H-pyran (DCJTB) in different emissive regions. The performance improvement was attributed to the optimization of energy barrier and the expansion of exciton formation zone within the DEL. - Highlights: • PhOLEDs by using a dual-emissive-layer structure to reduce efficiency roll-off were fabricated. • The DED exhibited 11% lower efficiency roll-off, 57% lower turn-on voltage, and 174% higher brightness than SED. • A DCJTB fluorescent probe was inserted at different positions of DED to investigate the expansion of exciton formation zone.

  2. Accuracy of an improved device for remote measuring of tree-trunk diameters

    International Nuclear Information System (INIS)

    Matsushita, T.; Kato, S.; Komiyama, A.

    2000-01-01

    For measuring the diameters of tree trunks from a distant position, a recent device using a laser beam was developed by Kantou. We improved this device to serve our own practical purposes. The improved device consists of a 1-m-long metal caliper and a small telescope sliding smoothly onto it. Using the cross hairs in the scope, one can measure both edges of an object on the caliper and calculate its length. The laser beam is used just for guiding the telescopic sights to the correct positions on the object. In this study, the accuracy of this new device was examined by measuring objects of differing lengths, the distance from the object, and the angle of elevation to the object. Since each result of the experiment predicted absolute errors of measurement of less than 3 mm, this new device will be suitable for the measurement of trunk diameters in the field

  3. Highly efficient and heavily-doped organic light-emitting devices based on an orange phosphorescent iridium complex

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Shunliang; Wang, Qi [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054 (China); Li, Ming [College of Chemistry, Sichuan University, Chengdu, 610064 (China); Lu, Zhiyun, E-mail: luzhiyun@scu.edu.cn [College of Chemistry, Sichuan University, Chengdu, 610064 (China); Yu, Junsheng, E-mail: jsyu@uestc.edu.cn [State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, University of Electronic Science and Technology of China (UESTC), Chengdu 610054 (China)

    2014-10-15

    Heavily doped and highly efficient phosphorescent organic light-emitting devices (PhOLEDs) had been fabricated by utilizing an orange iridium complex, bis[2-(3′,5′-di-tert-butylbiphenyl-4-yl)benzothiazolato-N,C{sup 2'}]iridium(III) (acetylacetonate) [(tbpbt){sub 2}Ir(acac)], as a phosphor. When the doping concentration of [(tbpbt){sub 2}Ir(acac)] reached as high as 15 wt%, the PhOLEDs exhibited a power efficiency, current efficiency, and external quantum efficiency of 24.5 lm/W, 32.1 cd/A, 15.7%, respectively, implying a promising quenching-resistant characteristics of this novel phosphor. Furthermore, the efficient white PhOLEDs had been obtained by employing (tbpbt){sub 2}Ir(acac) as a self-host orange emitter, indicating that (tbpbt){sub 2}Ir(acac) could serve as a promising phosphor to fabricate white organic light-emitting devices with simplified manufacturing process. - Highlights: • Efficient phosphorescent devices were fabricated. • Optimized phosphor doping ratio reached as high as 15 wt%. • The results proved a promising quench-resistant property of the phosphor. • Efficient white devices based on this phosphor as self-host layer had been realized.

  4. Highly efficient and heavily-doped organic light-emitting devices based on an orange phosphorescent iridium complex

    International Nuclear Information System (INIS)

    Zhou, Shunliang; Wang, Qi; Li, Ming; Lu, Zhiyun; Yu, Junsheng

    2014-01-01

    Heavily doped and highly efficient phosphorescent organic light-emitting devices (PhOLEDs) had been fabricated by utilizing an orange iridium complex, bis[2-(3′,5′-di-tert-butylbiphenyl-4-yl)benzothiazolato-N,C 2' ]iridium(III) (acetylacetonate) [(tbpbt) 2 Ir(acac)], as a phosphor. When the doping concentration of [(tbpbt) 2 Ir(acac)] reached as high as 15 wt%, the PhOLEDs exhibited a power efficiency, current efficiency, and external quantum efficiency of 24.5 lm/W, 32.1 cd/A, 15.7%, respectively, implying a promising quenching-resistant characteristics of this novel phosphor. Furthermore, the efficient white PhOLEDs had been obtained by employing (tbpbt) 2 Ir(acac) as a self-host orange emitter, indicating that (tbpbt) 2 Ir(acac) could serve as a promising phosphor to fabricate white organic light-emitting devices with simplified manufacturing process. - Highlights: • Efficient phosphorescent devices were fabricated. • Optimized phosphor doping ratio reached as high as 15 wt%. • The results proved a promising quench-resistant property of the phosphor. • Efficient white devices based on this phosphor as self-host layer had been realized

  5. Use of Physics Innovative Device for Improving Students‟ Motivation and Performance in Learning Selected Concepts in Physics

    Directory of Open Access Journals (Sweden)

    Virginia Songalia Sobremisana

    2017-11-01

    Full Text Available This research was focused on the development and evaluation of physics innovative device in enhancing students’ motivation and performance in learning selected concepts in physics. The Physics innovative device was developed based upon research on student difficulties in learning relevant concepts in physics and their attitudes toward the subject. Basic concepts in mechanics were also made as baselines in the development of the locally-produced Physics innovative learning device. Such learning devices are valuable resources when used either in lecture or demonstration classes. The developmental, descriptive and quasi-experimental research methods were utilized to determine the effectiveness, in terms of motivation and performance, of the innovative device in Physics. The instruments used for the data collection were the Instructional Materials Motivational Scale (IMMS developed by Keller and the students’ performance test. Pretest and posttest mean scores were measured to determine if there is a mean gain score difference between the experimental and control groups. The study revealed that the group taught with the Physics innovative device performed significantly better than those taught in the traditional method and also the use of Physics innovative device generally improved students’ understanding of concepts and led to higher academic achievements. Analysis of the students’ level of motivation showed that their interests were captured, the instructions they received were relevant to their personal goals and motives, their confidence to learn on their own were build-up, and learning for them was rewarding and important. In the four dimensions (ARCS of IMMS students were found to be attentive, confident, and in agreement in using the fun-learning tool having realize its applicability and relevance in learning their Physics lessons. Results of the study disclosed students and teachers consider the novel device acceptable because it is

  6. Use-related risk analysis for medical devices based on improved FMEA.

    Science.gov (United States)

    Liu, Long; Shuai, Ma; Wang, Zhu; Li, Ping

    2012-01-01

    In order to effectively analyze and control use-related risk of medical devices, quantitative methodologies must be applied. Failure Mode and Effects Analysis (FMEA) is a proactive technique for error detection and risk reduction. In this article, an improved FMEA based on Fuzzy Mathematics and Grey Relational Theory is developed to better carry out user-related risk analysis for medical devices. As an example, the analysis process using this improved FMEA method for a certain medical device (C-arm X-ray machine) is described.

  7. Improving efficiency (optimization) of CIGS thin film solar cell using ...

    African Journals Online (AJOL)

    Jsc ,Voc , FF and Quantum efficiency (QE) decrease due to absorption of electrons of electrons to the surface of back connection and their participation in recomposition. Efficiency increases from 20.3399% to 21.3721% by increasing impurity density of absorbent layer and efficiency increases to 28.9266% and the quantum ...

  8. 75 FR 27341 - Increasing Market and Planning Efficiency Through Improved Software; Notice of Technical...

    Science.gov (United States)

    2010-05-14

    ..., ramp rates, and network topology), flexible dispatch, settlement calculations, transmission switching... Market and Planning Efficiency Through Improved Software; Notice of Technical Conference To Discuss Increasing Market and Planning Efficiency Through Improved Software May 7, 2010. Take notice that Commission...

  9. High-Efficiency Multiscale Modeling of Cell Deformations in Confined Microenvironments in Microcirculation and Microfluidic Devices

    Science.gov (United States)

    Lu, Huijie; Peng, Zhangli

    2017-11-01

    Our goal is to develop a high-efficiency multiscale modeling method to predict the stress and deformation of cells during the interactions with their microenvironments in microcirculation and microfluidic devices, including red blood cells (RBCs) and circulating tumor cells (CTCs). There are more than 1 billion people in the world suffering from RBC diseases, e.g. anemia, sickle cell diseases, and malaria. The mechanical properties of RBCs are changed in these diseases due to molecular structure alternations, which is not only important for understanding the disease pathology but also provides an opportunity for diagnostics. On the other hand, the mechanical properties of cancer cells are also altered compared to healthy cells. This can lead to acquired ability to cross the narrow capillary networks and endothelial gaps, which is crucial for metastasis, the leading cause of cancer mortality. Therefore, it is important to predict the deformation and stress of RBCs and CTCs in microcirculations. We are developing a high-efficiency multiscale model of cell-fluid interaction to study these two topics.

  10. Configuration of dishwasher to improve energy efficiency of water heating

    Science.gov (United States)

    Gluesenkamp, Kyle R.

    2018-04-24

    A washing machine includes a sealed tub for accepting articles to be washed. A liquid circulation circuit sprays a pressurized liquid (e.g. water, detergent, solvent) around the articles to clean them. The liquid circulation circuit is in thermal contact with a hot side of a thermoelectric device. A heat sink is in thermal contact with both a cold side of the thermoelectric device and a heat sink charging circuit. A liquid is successively directed one or more times through the liquid circulation circuit with the thermoelectric device powered on, and then directed one or more times through the heat sink charging circuit with the thermoelectric device powered off. Finally, the liquid is discharged from the tub after having its temperature lowered by heat exchange to the heat sink.

  11. Improved efficiency of lifting freight on inclined mine shafts

    Energy Technology Data Exchange (ETDEWEB)

    Molchanov, A A

    1980-01-01

    Design and operating principles are described for a self-propelled inclined lifter with hinged-lever mechanism of forced compression of the drive wheels to the rails. Limit values are defined for the main parameters of the traction device.

  12. Process Cycle Efficiency Improvement Through Lean: A Case Study

    Directory of Open Access Journals (Sweden)

    P.V. Mohanram

    2011-06-01

    Full Text Available Lean manufacturing is an applied methodology of scientific, objective techniques that cause work tasks in a process to be performed with a minimum of non-value adding activities resulting in greatly reduced wait time, queue time, move time, administrative time, and other delays. This work addresses the implementation of lean principles in a construction equipment company. The prime objective is to evolve and test several strategies to eliminate waste on the shop floor. This paper describes an application of value stream mapping (VSM. Consequently, the present and future states of value stream maps are constructed to improve the production process by identifying waste and its sources. A noticeable reduction in cycle time and increase in cycle efficiency is confirmed. The production flow was optimized thus minimizing several non-value added activities/times such as bottlenecking time, waiting time, material handling time, etc. This case study can be useful in developing a more generic approach to design lean environment.

  13. Improving the efficiency of natural draft cooling towers

    Energy Technology Data Exchange (ETDEWEB)

    Smrekar, J. [Faculty of Mechanical Engineering, Askerceva 6, SI-1000 Ljubljana (Slovenia); Oman, J. [Faculty of Mechanical Engineering, Askerceva 6, SI-1000 Ljubljana (Slovenia)]. E-mail: janez.oman@fs.uni-lj.si; Sirok, B. [Faculty of Mechanical Engineering, Askerceva 6, SI-1000 Ljubljana (Slovenia)

    2006-06-15

    This study shows how the efficiency of a natural draft cooling tower can be improved by optimising the heat transfer along the cooling tower (CT) packing using a suitable water distribution across the plane area of the cooling tower. On the basis of cooling air measurements, it is possible to distribute the water in such a way that it approaches the optimal local water/air mass flow ratio and ensures the homogeneity of the heat transfer and a reduction of entropy generation, thus minimising the amount of exergy lost. The velocity and temperature fields of the air flow were measured with the aid of a remote control mobile robot unit that was developed to enable measurements at an arbitrary point above the spray zone over the entire plane area of the cooling tower. The topological structures of the moist air velocity profiles and the temperature profiles above the spray zone were used as input data for calculation of the local entropy generation in the tower. On the basis of the measured boundary conditions, a numerical analysis of the influence of the water distribution across the cooling tower's plane area on entropy generation and exergy destruction in the cooling tower was conducted.

  14. Improve the efficiency of PEMFC using neutron imaging

    International Nuclear Information System (INIS)

    Kim, Tae Joo; Shim, Chulmuu

    2010-01-01

    The water management is one of the most critical issues for PEMFC commercialization. In order to make a proper scheme for water management, the information of water distribution and behavior is very important. But the visualization is difficult due to metallic coverage. Recently, neutron imaging has joined the canon of diagnostic methods for fuel cell research and is applied worldwide with qualitative and quantitative results. In this investigation, we prepared 3-parallel serpentine single PEMFC. The active area is 250 mm 2 and channel size is 1 Χ 1 mm, respectively. Distribution and transport of water in an operating PEMFC were observed as functions of flow directions and differential pressures between anode and cathodes. This investigation was performed at BST-2, Nest. The collimation ratio is 600 and neutron fluence of BST-2 is 7.2 Χ 10 6 n/s, respectively. Neutron image was captured by A-Si detector with 1 sec expsosure time. The PEMFC has different performances for each differential pressure and flow directions. When the neutron images are compared with operating conditions, the distribution and behavior of water are different. Total water fraction is increased and then decreases as the current density increases. This situation is similar trend for the flow directions. It is shown that neutron imaging technique is powerful tool to visualize the PEMFC and the water distribution and behavior of an operating PEMFC helps improve the efficiency of PEMFC

  15. Improving the efficiency of natural draft cooling towers

    International Nuclear Information System (INIS)

    Smrekar, J.; Oman, J.; Sirok, B.

    2006-01-01

    This study shows how the efficiency of a natural draft cooling tower can be improved by optimising the heat transfer along the cooling tower (CT) packing using a suitable water distribution across the plane area of the cooling tower. On the basis of cooling air measurements, it is possible to distribute the water in such a way that it approaches the optimal local water/air mass flow ratio and ensures the homogeneity of the heat transfer and a reduction of entropy generation, thus minimising the amount of exergy lost. The velocity and temperature fields of the air flow were measured with the aid of a remote control mobile robot unit that was developed to enable measurements at an arbitrary point above the spray zone over the entire plane area of the cooling tower. The topological structures of the moist air velocity profiles and the temperature profiles above the spray zone were used as input data for calculation of the local entropy generation in the tower. On the basis of the measured boundary conditions, a numerical analysis of the influence of the water distribution across the cooling tower's plane area on entropy generation and exergy destruction in the cooling tower was conducted

  16. Retrofit of ammonia plant for improving energy efficiency

    International Nuclear Information System (INIS)

    Panjeshahi, M.H.; Ghasemian Langeroudi, E.; Tahouni, N.

    2008-01-01

    The aim of this work is to perform a retrofit study of an ammonia plant, in purpose of improving energy efficiency. As a common practice, one can divide an ammonia plant into two parts: the hot-end and the cold-end. In the hot section, two different options are investigated that both lead to a threshold condition and achieve maximum energy saving. The first option covers only process-to-process energy integration, while the second option considers some modification in the convection section of the primary reformer through a new arrangement of the heating coils. Thus, a considerable reduction in cooling water, HP steam and fuel gas consumption is achieved. In the cold section, retrofit study is dominated by reducing the amount of shaft work or power consumption in the refrigeration system. Application of the Combined Pinch and Exergy Analysis revealed that part of the shaft work, which was originally being used, was inefficient and could have been avoided in a well-integrated design. Therefore, by proposing optimum refrigeration levels, reasonable saving (15%) in power consumption was observed without the need for new investment

  17. CERAMIC MEMBRANE ENABLING TECHNOLOGY FOR IMPROVED IGCC EFFICIENCY

    International Nuclear Information System (INIS)

    Ravi Prasad

    2000-01-01

    The objective of this program is to conduct a technology development program to advance the state-of-the-art in ceramic Oxygen Transport Membranes (OTM) to the level required to produce step change improvements in process economics, efficiency, and environmental benefits for commercial IGCC systems and other applications. The IGCC program is focused on addressing key issues in materials, processing, manufacturing, engineering and system development that will make the OTM a commercial reality. The objective of the OTM materials development task is to identify a suitable material that can be formed into a thin film to produce the target oxygen flux. This requires that the material have an adequate permeation rate, and thermo-mechanical and thermo-chemical properties such that the material is able to be supported on the desired substrate and sufficient mechanical strength to survive the stresses involved in operation. The objective of the composite OTM development task is to develop the architecture and fabrication techniques necessary to construct stable, high performance, thin film OTMs supported on suitable porous, load bearing substrates. The objective of the process development task of this program to demonstrate the program objectives on a single OTM tube under test conditions simulating those of the optimum process cycle for the power plant

  18. A Retrofit Tool for Improving Energy Efficiency of Commercial Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Levine, Mark; Feng, Wei; Ke, Jing; Hong, Tianzhen; Zhou, Nan

    2013-06-06

    Existing buildings will dominate energy use in commercial buildings in the United States for three decades or longer and even in China for the about two decades. Retrofitting these buildings to improve energy efficiency and reduce energy use is thus critical to achieving the target of reducing energy use in the buildings sector. However there are few evaluation tools that can quickly identify and evaluate energy savings and cost effectiveness of energy conservation measures (ECMs) for retrofits, especially for buildings in China. This paper discusses methods used to develop such a tool and demonstrates an application of the tool for a retrofit analysis. The tool builds on a building performance database with pre-calculated energy consumption of ECMs for selected commercial prototype buildings using the EnergyPlus program. The tool allows users to evaluate individual ECMs or a package of ECMs. It covers building envelope, lighting and daylighting, HVAC, plug loads, service hot water, and renewable energy. The prototype building can be customized to represent an actual building with some limitations. Energy consumption from utility bills can be entered into the tool to compare and calibrate the energy use of the prototype building. The tool currently can evaluate energy savings and payback of ECMs for shopping malls in China. We have used the tool to assess energy and cost savings for retrofit of the prototype shopping mall in Shanghai. Future work on the tool will simplify its use and expand it to cover other commercial building types and other countries.

  19. Improving power conversion efficiency of perovskite solar cells by cooperative LSPR of gold-silver dual nanoparticles

    Institute of Scientific and Technical Information of China (English)

    Peng Liu; Cong-hua Zhou; Bing-chu Yang; Gang Liu; Run-sheng Wu; Chu-jun Zhang; Fang Wan; Shui-gen Li; Jun-liang Yang; Yong-li Gao

    2017-01-01

    Enhancing optical and electrical performances is effective in improving power conversion efficiency of photovoltaic devices.Here,gold and silver dual nanoparticles were imported and embedded in the hole transport layer of perovskite solar cells.Due to the cooperative localized surface plasmon resonance of these two kinds of metal nanostructures,light harvest of perovskite material layer and the electrical performance of device were improved,which finally upgraded short circuit current density by 10.0%,and helped to increase power conversion efficiency from 10.4% to 11.6% under AM 1.5G illumination with intensity of 100 mW/cm2.In addition,we explored the influence of silver and gold nanoparticles on charge carrier generation,dissociation,recombination,and transportation inside perovskite solar cells.

  20. Improved power efficiency of blue fluorescent organic light-emitting diode with intermixed host structure

    Energy Technology Data Exchange (ETDEWEB)

    Yue, Shouzhen; Zhang, Shiming; Zhang, Zhensong; Wu, Yukun; Wang, Peng; Guo, Runda; Chen, Yu; Qu, Dalong; Wu, Qingyang; Zhao, Yi, E-mail: yizhao@jlu.edu.cn; Liu, Shiyong

    2013-11-15

    High power efficiency (PE) p-bis(p-N,N-diphenyl-aminostyryl)benzene (DSA-ph) based fluorescent blue organic light-emitting diode (OLED) is demonstrated by utilizing intermixed host (IH) structure. The PE outperforms those devices based on single host (SH), mixed host (MH), and double emitting layers (DELs). By further optimizing the intermixed layer, peak PE of the IH device is increased up to 8.7 lm/W (1.7 times higher than conventional SH device), which is the highest value among the DSA-ph based blue device reported so far. -- Highlights: • DSA-ph based blue fluorescent OLEDs are fabricated. • The intermixed host structure is first introduced into the blue devices. • Blue device with the highest power efficiency based on DSA-ph is obtained.

  1. IMPROVING CO2 EFFICIENCY FOR RECOVERING OIL IN HETEROGENEOUS RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Reid B. Grigg

    2003-10-31

    The second annual report of ''Improving CO{sub 2} Efficiency for Recovery Oil in Heterogeneous Reservoirs'' presents results of laboratory studies with related analytical models for improved oil recovery. All studies have been undertaken with the intention to optimize utilization and extend the practice of CO{sub 2} flooding to a wider range of reservoirs. Many items presented in this report are applicable to other interest areas: e.g. gas injection and production, greenhouse gas sequestration, chemical flooding, reservoir damage, etc. Major areas of studies include reduction of CO{sub 2} mobility to improve conformance, determining and understanding injectivity changes in particular injectivity loses, and modeling process mechanisms determined in the first two areas. Interfacial tension (IFT) between a high-pressure, high-temperature CO{sub 2} and brine/surfactant and foam stability are used to assess and screen surfactant systems. In this work the effects of salinity, pressure, temperature, surfactant concentration, and the presence of oil on IFT and CO{sub 2} foam stability were determined on the surfactant (CD1045{trademark}). Temperature, pressure, and surfactant concentration effected both IFT and foam stability while oil destabilized the foam, but did not destroy it. Calcium lignosulfonate (CLS) can be used as a sacrificial and an enhancing agent. This work indicates that on Berea sandstone CLS concentration, brine salinity, and temperature are dominant affects on both adsorption and desorption and that adsorption is not totally reversible. Additionally, CLS adsorption was tested on five minerals common to oil reservoirs; it was found that CLS concentration, salinity, temperature, and mineral type had significant effects on adsorption. The adsorption density from most to least was: bentonite > kaolinite > dolomite > calcite > silica. This work demonstrates the extent of dissolution and precipitation from co-injection of CO{sub 2} and

  2. Improved quantum efficiency models of CZTSe: GE nanolayer solar cells with a linear electric field.

    Science.gov (United States)

    Lee, Sanghyun; Price, Kent J; Saucedo, Edgardo; Giraldo, Sergio

    2018-02-08

    We fabricated and characterized CZTSe:Ge nanolayer (quantum efficiency for Ge doped CZTSe devices. The linear electric field model is developed with the incomplete gamma function of the quantum efficiency as compared to the empirical data at forward bias conditions. This model is characterized with a consistent set of parameters from a series of measurements and the literature. Using the analytical modelling method, the carrier collection profile in the absorber is calculated and closely fitted by the developed mathematical expressions to identify the carrier dynamics during the quantum efficiency measurement of the device. The analytical calculation is compared with the measured quantum efficiency data at various bias conditions.

  3. InP/ZnSe/ZnS core-multishell quantum dots for improved luminescence efficiency

    Science.gov (United States)

    Greco, Tonino; Ippen, Christian; Wedel, Armin

    2012-04-01

    Semiconductor quantum dots (QDs) exhibit unique optical properties like size-tunable emission color, narrow emission peak, and high luminescence efficiency. QDs are therefore investigated towards their application in light-emitting devices (QLEDs), solar cells, and for bio-imaging purposes. In most cases QDs made from cadmium compounds like CdS, CdSe or CdTe are studied because of their facile and reliable synthesis. However, due to the toxicity of Cd compounds and the corresponding regulation (e.g. RoHS directive in Europe) these materials are not feasible for customer applications. Indium phosphide is considered to be the most promising alternative because of the similar band gap (InP 1.35 eV, CdSe 1.73 eV). InP QDs do not yet reach the quality of CdSe QDs, especially in terms of photoluminescence quantum yield and peak width. Typically, QDs are coated with another semiconductor material of wider band gap, often ZnS, to passivate surface defects and thus improve luminescence efficiency. Concerning CdSe QDs, multishell coatings like CdSe/CdS/ZnS or CdSe/ZnSe/ZnS have been shown to be advantageous due to the improved compatibility of lattice constants. Here we present a method to improve the luminescence efficiency of InP QDs by coating a ZnSe/ZnS multishell instead of a ZnS single shell. ZnSe exhibits an intermediate lattice constant of 5.67 Å between those of InP (5.87 Å) and ZnS (5.41 Å) and thus acts as a wetting layer. As a result, InP/ZnSe/ZnS is introduced as a new core-shell quantum dot material which shows improved photoluminescence quantum yield (up to 75 %) compared to the conventional InP/ZnS system.

  4. Wild Band Edges: The Role of Bandgap Grading and Band-Edge Fluctuations in High-Efficiency Chalcogenide Devices: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Repins, Ingrid; Mansfield, Lorelle; Kanevce, Ana; Jensen, Soren A.; Kuciauskas, Darius; Glynn, Stephen; Barnes, Teresa; Metzger, Wyatt; Burst, James; Jiang, Chun-Sheng; Dippo, Patricia; Harvey, Steve; Teeter, Glenn; Perkins, Craig; Egaas, Brian; Zakutayev, Andriy; Alsmeier, J.-H.; Lussky, T.; Korte, L.; Wilks, R. G.; Bar, M.; Yan, Y.; Lany, Stephan; Zawadzki, Pawel; Park, Ji-Sang; Wei, Suhuai

    2016-06-16

    Band-edge effects -- including grading, electrostatic fluctuations, bandgap fluctuations, and band tails -- affect chalcogenide device efficiency. These effects now require more careful consideration as efficiencies increase beyond 20%. Several aspects of the relationships between band-edge phenomena and device performance for NREL absorbers are examined. For Cu(In,Ga)Se2 devices, recent increases in diffusion length imply changes to optimum bandgap profile. The origin, impact, and modification of electrostatic and bandgap fluctuations are also discussed. The application of the same principles to devices based on CdTe, kesterites, and emerging absorbers (Cu2SnS3, CuSbS2), considering differences in materials properties and defect formation energies, is examined.

  5. Interplay between efficiency and device architecture for small molecule organic solar cells.

    Science.gov (United States)

    Williams, Graeme; Sutty, Sibi; Aziz, Hany

    2014-06-21

    Small molecule organic solar cells (OSCs) have experienced a resurgence of interest over their polymer solar cell counterparts, owing to their improved batch-to-batch (thus, cell-to-cell) reliability. In this systematic study on OSC device architecture, we investigate five different small molecule OSC structures, including the simple planar heterojunction (PHJ) and bulk heterojunction (BHJ), as well as several planar-mixed structures. The different OSC structures are studied over a wide range of donor:acceptor mixing concentrations to gain a comprehensive understanding of their charge transport behavior. Transient photocurrent decay measurements provide crucial information regarding the interplay between charge sweep-out and charge recombination, and ultimately hint toward space charge effects in planar-mixed structures. Results show that the BHJ/acceptor architecture, comprising a BHJ layer with high C60 acceptor content, generates OSCs with the highest performance by balancing charge generation with charge collection. The performance of other device architectures is largely limited by hole transport, with associated hole accumulation and space charge effects.

  6. Field Performance versus Standard Test Condition Efficiency of Tandem Solar Cells and the Specific Case of Perovskites/Silicon Devices

    KAUST Repository

    Dupre, Olivier

    2018-01-05

    Multijunction cells may offer a cost-effective route to boost the efficiency of industrial photovoltaics. For any technology to be deployed in the field, its performance under actual operating conditions is extremely important. In this perspective, we evaluate the impact of spectrum, light intensity, and module temperature variations on the efficiency of tandem devices with crystalline silicon bottom cells with a particular focus on perovskite top cells. We consider devices with different efficiencies and calculate their energy yields using field data from Denver. We find that annual losses due to differences between operating conditions and standard test conditions are similar for single-junction and four-terminal tandem devices. The additional loss for the two-terminal tandem configuration caused by current mismatch reduces its performance ratio by only 1.7% when an optimal top cell bandgap is used. Additionally, the unusual bandgap temperature dependence of perovskites is shown to have a positive, compensating effect on current mismatch.

  7. Power Factor Improvement Using Automatic Power Factor Compensation (APFC Device for Medical Industries in Malaysia

    Directory of Open Access Journals (Sweden)

    Zaidi Maryam Nabihah

    2018-01-01

    Full Text Available This paper present the project designed to correcting power factor for medical industries in Malaysia automatically. Which with hope to make the cost and energy usage efficient, because the energy source are depleting due to increase in population. Power factor is the ratio of real power and apparent power. This definition is mathematically represented as kW/kVA where kW is active power and kVA is apparent power (active + reactive. Reactive power is the non-working power generated by the magnetic and inductive load to generate magnetic flux. The increase in reactive power increase the apparent power so the power factor will decrease. Low pF will cause the industry to meet high demand thus making it less efficient. The main aim of this project is to increasing the current power factor of medical industries from 0.85 to 0.90. Power factor compensation contribute to reduction in current-dependent losses and increase energy efficiency while expanding the reliability of planning for future energy network. As technology develops, the gradual cost and efficiency penalty should reduce. Therefore, automatic power factor compensation device should become cost-effective and smaller device over time. That is the reason this project is using programmable device as it is a miniature architecture device.

  8. Improvement in distance and near visual acuities using low vision devices in diabetic retinopathy

    Directory of Open Access Journals (Sweden)

    Sarika Gopalakrishnan

    2017-01-01

    Full Text Available Purpose: The aim of this study is to elucidate the causes and level of visual impairment (VI in patients with different pathologies of diabetic retinopathy (DR who presented to a low vision care (LVC clinic, to analyze the type of distant and near devices prescribed to them and the visual benefits thereof. Methods: A retrospective chart review was done for 100 consecutive patients with DR who were referred to the LVC clinic from June 2015 to June 2016. The reason for referral was assessed from the electronic medical records and available fundus photographs, fundus fluorescein angiograms, and optical coherence tomography images by a retina specialist. The details of low-vision devices and subsequent improvements were noted. Results: Of the 100 patients, 52% had moderate VI, 19% mild VI, 16% severe VI, and 13% had profound VI or blindness. The most commonly prescribed low vision device was half-eye spectacles (38.4%. The pathologies which had statistically significant improvement (P < 0.05 in distance vision with low vision devices were DR with disc pallor (4.4% improvement, ischemic maculopathy (11.9% improvement, and plaque of hard exudate (10.1% improvement. However, in all pathologies, there was statistically significant improvement (P < 0.05 in near vision. Conclusion: Usually, the patients with DR presented to the LVC clinic with moderate VI. The use of low vision devices can help these patients in cases where medical and surgical treatment have no or a limited role in restoring useful vision.

  9. Charge collection efficiency degradation induced by MeV ions in semiconductor devices: Model and experiment

    Energy Technology Data Exchange (ETDEWEB)

    Vittone, E., E-mail: ettore.vittone@unito.it [Department of Physics, NIS Research Centre and CNISM, University of Torino, via P. Giuria 1, 10125 Torino (Italy); Pastuovic, Z. [Centre for Accelerator Science (ANSTO), Locked bag 2001, Kirrawee DC, NSW 2234 (Australia); Breese, M.B.H. [Centre for Ion Beam Applications (CIBA), Department of Physics, National University of Singapore, Singapore 117542 (Singapore); Garcia Lopez, J. [Centro Nacional de Aceleradores (CNA), Sevilla University, J. Andalucia, CSIC, Av. Thomas A. Edison 7, 41092 Sevilla (Spain); Jaksic, M. [Department for Experimental Physics, Ruder Boškovic Institute (RBI), P.O. Box 180, 10002 Zagreb (Croatia); Raisanen, J. [Department of Physics, University of Helsinki, Helsinki 00014 (Finland); Siegele, R. [Centre for Accelerator Science (ANSTO), Locked bag 2001, Kirrawee DC, NSW 2234 (Australia); Simon, A. [International Atomic Energy Agency (IAEA), Vienna International Centre, P.O. Box 100, 1400 Vienna (Austria); Institute of Nuclear Research of the Hungarian Academy of Sciences (ATOMKI), Debrecen (Hungary); Vizkelethy, G. [Sandia National Laboratories (SNL), PO Box 5800, Albuquerque, NM (United States)

    2016-04-01

    Highlights: • We study the electronic degradation of semiconductors induced by ion irradiation. • The experimental protocol is based on MeV ion microbeam irradiation. • The radiation induced damage is measured by IBIC. • The general model fits the experimental data in the low level damage regime. • Key parameters relevant to the intrinsic radiation hardness are extracted. - Abstract: This paper investigates both theoretically and experimentally the charge collection efficiency (CCE) degradation in silicon diodes induced by energetic ions. Ion Beam Induced Charge (IBIC) measurements carried out on n- and p-type silicon diodes which were previously irradiated with MeV He ions show evidence that the CCE degradation does not only depend on the mass, energy and fluence of the damaging ion, but also depends on the ion probe species and on the polarization state of the device. A general one-dimensional model is derived, which accounts for the ion-induced defect distribution, the ionization profile of the probing ion and the charge induction mechanism. Using the ionizing and non-ionizing energy loss profiles resulting from simulations based on the binary collision approximation and on the electrostatic/transport parameters of the diode under study as input, the model is able to accurately reproduce the experimental CCE degradation curves without introducing any phenomenological additional term or formula. Although limited to low level of damage, the model is quite general, including the displacement damage approach as a special case and can be applied to any semiconductor device. It provides a method to measure the capture coefficients of the radiation induced recombination centres. They can be considered indexes, which can contribute to assessing the relative radiation hardness of semiconductor materials.

  10. Case study: improving efficiency in a large hospital laboratory.

    Science.gov (United States)

    Bartel, Marilynn

    2004-01-01

    Saint Francis Health System (SFHS) consists of three hospitals and one clinic: Saint Francis Hospital (SFH); Broken Arrow Medical Center; Laureate Psychiatric Hospital; and Warren Clinic. SFHS has 670 physicians on staff and serves medical (oncology, orthopedic, neurology, and renal), surgical, cardiac, women and infant, pediatric, transplant, and trauma patients in Tulsa County, Oklahoma, which has a population of 660,000. SFH incorporates 706 staffed beds, including 126 pediatric beds and 119 critical care beds. Each year, the health system averages 38,000 admissions, 70,000 emergency department visits, 25,000 surgeries, and 3,500 births. Saint Francis Laboratory is located within the main hospital facility (SFH) and functions as a core lab for the health system. The lab also coordinates lab services with Saint Francis Heart Hospital, a physician-system joint venture. The Optimal Equipment Configuration (OEC) Project was designed by the Clinical Laboratory Services division of Premier, a group purchasing organization, with the goal of determining whether laboratories could improve efficiency and decrease unit cost by using a single-source vendor. Participants included seven business partners (Abbott, Bayer, Beckman/Coulter, Dade/Behring, J&J/ Ortho, Olympus, and Roche) and 21 laboratory sites (a small, mid-sized, and large site for each vendor). SFH laboratory staff embraced Premier's concept and viewed the OEC project as an opportunity to "energize" laboratory operations. SFH partnered with Abbott, their primary equipment vendor, for the project. Using resources and tools made available through the project, the laboratory was re-engineered to simplify workflow, increase productivity, and decrease costs by adding automation and changing to centralized specimen processing. Abbott and SFH shared a common vision for the project and enhanced their partnership through increased communication and problem solving. Abbott's area representatives provided for third

  11. Identify: Improving industrial energy efficiency and mitigating global climate change

    Energy Technology Data Exchange (ETDEWEB)

    Lazarus, M.; Hill, D.; Cornland, D.W.; Heaps, C.; Hippel, D. von; Williams, R.

    1997-07-01

    The use of energy in the industrial sectors of nations with both industrialized and developing economies will continue to be, a major source of greenhouse gas (GHG) emissions, particularly carbon dioxide. The patterns of industrial-sector energy use--energy provided primarily by the combustion of fossil fuels-have shifted both within the between countries in recent decades. Projections of future energy use and carbon-dioxide (CO{sub 2}) emissions suggest continued shifts in these patterns, as industrial production in developed countries stabilizes and declines, while industrial output in the developing world continues to expand. This expansion of industrial-sector activity and CO{sub 2} emissions in developing countries presents both a challenge and an opportunity. To seize this opportunity and contribute to international efforts to mitigate global climate change, the United National Industrial Development Organization (UNIDO) recently initiated a two-phase effort to help improve the efficiency of energy-intensive industries (iron and steel, chemicals, refining, paper and pulp, and cement) in developing countries. As part of the Phase I, the authors reviewed industrial sector scenarios and to initiated development of a software-based toolkit for identifying and assessing GHG mitigating technologies. This toolkit, called IDENTIFY, is comprised of a technology inventory and a companion economic analysis tool. In addition, UNIDO commissioned institutions in India, South Africa, and Argentina to review energy use patterns and savings opportunities in selected industries across nine developing countries, and contribute to the development of the IDENTIFY toolkit. UNIDO is now preparing to launch Phase 2, which will focus on full development and dissemination of the IDENTIFY toolkit through seminars and case studies around the world. This paper describes Phase 1 of the UNIDO project.

  12. Identify: Improving industrial energy efficiency and mitigating global climate change

    International Nuclear Information System (INIS)

    Lazarus, M.; Hill, D.; Cornland, D.W.; Heaps, C.; Hippel, D. von; Williams, R.

    1997-01-01

    The use of energy in the industrial sectors of nations with both industrialized and developing economies will continue to be, a major source of greenhouse gas (GHG) emissions, particularly carbon dioxide. The patterns of industrial-sector energy use--energy provided primarily by the combustion of fossil fuels-have shifted both within the between countries in recent decades. Projections of future energy use and carbon-dioxide (CO 2 ) emissions suggest continued shifts in these patterns, as industrial production in developed countries stabilizes and declines, while industrial output in the developing world continues to expand. This expansion of industrial-sector activity and CO 2 emissions in developing countries presents both a challenge and an opportunity. To seize this opportunity and contribute to international efforts to mitigate global climate change, the United National Industrial Development Organization (UNIDO) recently initiated a two-phase effort to help improve the efficiency of energy-intensive industries (iron and steel, chemicals, refining, paper and pulp, and cement) in developing countries. As part of the Phase I, the authors reviewed industrial sector scenarios and to initiated development of a software-based toolkit for identifying and assessing GHG mitigating technologies. This toolkit, called IDENTIFY, is comprised of a technology inventory and a companion economic analysis tool. In addition, UNIDO commissioned institutions in India, South Africa, and Argentina to review energy use patterns and savings opportunities in selected industries across nine developing countries, and contribute to the development of the IDENTIFY toolkit. UNIDO is now preparing to launch Phase 2, which will focus on full development and dissemination of the IDENTIFY toolkit through seminars and case studies around the world. This paper describes Phase 1 of the UNIDO project

  13. Developing concepts for improved efficiency of robot work preparation

    NARCIS (Netherlands)

    Essers, M.S.; Vaneker, Thomas H.J.

    2013-01-01

    SInBot[1] is a large research project that focuses on maximizing the efficient use of mobile industrial robots during medium sized production runs. The system that will be described in this paper will focusses on the development and validation of concepts for efficient work preparation for cells of

  14. Efficient, air-stable quantum dots light-emitting devices with MoO3 modifying the anode

    International Nuclear Information System (INIS)

    Meng, Xiangdong; Ji, Wenyu; Hua, Jie; Yu, Zhaoliang; Zhang, Yan; Li, Haibo; Zhao, Jialong

    2013-01-01

    In this work, we fabricated quantum dots light-emitting devices with hole-injection layer, molybdenum oxide (MoO 3 ) substituting for poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) which is hygroscopic and acidic and, therefore, a source of interface instability. A significant enhancement in luminance and current efficiency in MoO 3 -containing devices was observed. In addition, MoO 3 -containing devices were more stable in the air than those with PEDOT:PSS as the hole injection layer. The hole injection and transport of the devices were studied by the J–V characteristics of the hole-only devices. The excellent performance of the devices was principally a result of MoO 3 possessing lower injection barrier for the hole and better stability than PEDOT:PSS. -- Highlights: • We fabricated QD-LEDs with MoO 3 substituting for PEDOT:PSS as hole-injection layer. • A enhancement in luminance and efficiency in MoO 3 -containing device was observed. • The enhancement was originated from the stability and easy hole injection of MoO 3

  15. Functionalized carbon nanotube doping of P3HT:PCBM photovoltaic devices for enhancing short circuit current and efficiency

    Directory of Open Access Journals (Sweden)

    Rohit Bhatia

    2017-03-01

    Full Text Available We have successfully functionalized multiwalled carbon nanotubes (MWCNTs using nitrene approach employing the two aryl azides as a precursor for nitrene generation. The dispersion of functionalized MWCNTs has been enhanced in various organic solvents. These functionalized MWCNTs have been successfully doped in various concentrations in the bulk heterojunction (BHJ organic photovoltaic (OPV cells with a poly (3-hexyl thiophene (P3HT and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM photoactive blended layer. The incorporation of MWCNTs with aryl functional groups, in active the layer, results in enhanced performance with respect to a reference cell. The maximum power conversion efficiency of 1.86% is achieved with adduct I while in the case of adduct II it gets double to 2.0% in comparison with a reference cell. This improvement in the device performance is attributed to enhanced exciton dissociation and improved charge transport properties due to the formation of a nanotube percolation network in the photoactive composite layer.

  16. Energy-Efficient Multicast Transmission for Underlay Device-to-Device Communications: A Social-Aware Perspective

    Directory of Open Access Journals (Sweden)

    Fan Jiang

    2017-01-01

    Full Text Available In this paper, by utilizing the social relationships among mobile users, we present a framework of energy-efficient cluster formation and resource allocation for multicast D2D transmission. In particular, we first deal with D2D multicast cluster/group formation strategy from both physical distance and social trust level. Then we aim to maximize the overall energy-efficiency of D2D multicast groups through resource allocation and power control scheme, which considers the quality-of-service (QoS requirements of both cellular user equipment and D2D groups. A heuristic algorithm is proposed to solve above energy-efficiency problem with less complexity. After that, considering the limited battery capacity of mobile users, we propose an energy and social aware cluster head update algorithm, which incorporates both the energy constraint and social centrality measurement. Numerical results indicate that the proposed social-tie based D2D multicast group formation and update algorithm form a multicast group in an energy efficient way. Moreover, the proposed resource and power allocation scheme achieves better energy efficiency in terms of throughput per energy consumption. These results show that, by exploiting social domain information, underlay D2D multicast transmission has high practical potential in saving the source on wireless links and in the backhaul.

  17. Monolayer-Mediated Growth of Organic Semiconductor Films with Improved Device Performance.

    Science.gov (United States)

    Huang, Lizhen; Hu, Xiaorong; Chi, Lifeng

    2015-09-15

    Increased interest in wearable and smart electronics is driving numerous research works on organic electronics. The control of film growth and patterning is of great importance when targeting high-performance organic semiconductor devices. In this Feature Article, we summarize our recent work focusing on the growth, crystallization, and device operation of organic semiconductors intermediated by ultrathin organic films (in most cases, only a monolayer). The site-selective growth, modified crystallization and morphology, and improved device performance of organic semiconductor films are demonstrated with the help of the inducing layers, including patterned and uniform Langmuir-Blodgett monolayers, crystalline ultrathin organic films, and self-assembled polymer brush films. The introduction of the inducing layers could dramatically change the diffusion of the organic semiconductors on the surface and the interactions between the active layer with the inducing layer, leading to improved aggregation/crystallization behavior and device performance.

  18. Study to Improve Security for IoT Smart Device Controller: Drawbacks and Countermeasures

    Directory of Open Access Journals (Sweden)

    Xin Su

    2018-01-01

    Full Text Available Including mobile environment, conventional security mechanisms have been adapted to satisfy the needs of users. However, the device environment-IoT-based number of connected devices is quite different to the previous traditional desktop PC- or mobile-based environment. Based on the IoT, different kinds of smart and mobile devices are fully connected automatically via device controller, such as smartphone. Therefore, controller must be secure compared to conventional security mechanism. According to the existing security threats, these are quite different from the previous ones. Thus, the countermeasures applied should be changed. However, the smart device-based authentication techniques that have been proposed to date are not adequate in terms of usability and security. From the viewpoint of usability, the environment is based on mobility, and thus devices are designed and developed to enhance their owners’ efficiency. Thus, in all applications, there is a need to consider usability, even when the application is a security mechanism. Typically, mobility is emphasized over security. However, considering that the major characteristic of a device controller is deeply related to its owner’s private information, a security technique that is robust to all kinds of attacks is mandatory. In this paper, we focus on security. First, in terms of security achievement, we investigate and categorize conventional attacks and emerging issues and then analyze conventional and existing countermeasures, respectively. Finally, as countermeasure concepts, we propose several representative methods.

  19. Availability and improvement of a vacuum-type immobilization device in pediatric CT

    International Nuclear Information System (INIS)

    Tani, Shoji; Mizuno, Naoto; Abe, Syuji

    2002-01-01

    The essential factors for an immobilization device in pediatric CT are absence of artifacts, safety, no disturbance of the patient's sedation, and ease of handling. We evaluated the suitability of a commercially available vacuum-type immobilization device designed for radiation therapy (Vac-Lok) that meets these requisites. There were no artifacts in scans of the water phantom. The device easily immobilized the patient, was quick to release, and was superior to previous immobilization systems, according to replies to a questionnaire administered to physicians, technologists, and nurses. Schedule delays were reduced by using this device to examine sedated patients (up to 1 year of age). Despite these advantages, the device was too small to immobilize both extremities together when examining older patients. In order to overcome this problem, we invented a special immobilization device for pediatric CT. The new device could be applied to taller patients, up to 85 cm in height (the average height of 2-year-old infants), and was able to contribute to efficient utilization of the examination room. (author)

  20. The development of furrower model blade to paddlewheel aerator for improving aeration efficiency

    Science.gov (United States)

    Bahri, Samsul; Praeko Agus Setiawan, Radite; Hermawan, Wawan; Zairin Junior, Muhammad

    2018-05-01

    The successful of intensive aquaculture is strongly influenced by the ability of the farmers to overcome the deterioration of water quality. The problem is low dissolved oxygen through aeration process. The aerator device which widely used in pond farming is paddle wheel aerator because it is the best aerator in aeration mechanism and usable driven power. However, this aerator still has a low performance of aeration, so that the cost of aerator operational for aquaculture is still high. Up to now, the effort to improve the performance of aeration was made by two-dimensional blade design. Obviously, it does not provide the optimum result due to the power requirements for aeration is directly proportional to the increase of aeration rate. The aim of this research is to develop three-dimensional model furrowed blades. Design of Furrower model blades was 1.6 cm diameter hole, 45º of vertical angle blade position and 30º of the horizontal position. The optimum performance furrowed model blades operated on the submerged blade 9 cm with 567.54 Watt of electrical power consumption and 4.322 m3 of splash coverage volume. The standard efficiency aeration is 2.72 kg O2 kWh-1. The furrowed model blades can improve the aeration efficiency of paddlewheel aerator.

  1. Cermet insert high voltage holdoff improvement for ceramic/metal vacuum devices

    Science.gov (United States)

    Ierna, W.F.

    1986-03-11

    An improved metal-to-ceramic seal is provided wherein the ceramic body of the seal contains an integral region of cermet material in electrical contact with the metallic member, e.g., an electrode, of the seal. The seal is useful in high voltage vacuum devices, e.g., vacuum switches, and increases the high-voltage holdoff capabilities of such devices. A method of fabricating such seals is also provided.

  2. Improvement of cosmic ray ruggedness of hybrid vehicles power semiconductor devices

    International Nuclear Information System (INIS)

    Nishida, Shuichi; Ohnishi, Toyokazu; Fujikawa, Touma; Nose, Noboru; Hamada, Kimimori; Shoji, Tomoyuki; Ishiko, Masayasu

    2010-01-01

    Power semiconductors which are used under high voltage conditions in HVs (Hybrid Vehicles) are required to have high destruction tolerance against cosmic rays as well as to meet conventional quality standards. In this paper, an SEB (Single Event Burnout) failure mechanism induced by cosmic rays in IGBTs (Insulated Gate Bipolar Transistors) was investigated. Through an optimized device design in which thyristor action was suppressed, the device destruction tolerance was greatly improved. (author)

  3. Feasibility Study of Interactive Game Technologies to Improve Experience with Inhaler Spacer Devices in Young Children

    OpenAIRE

    Aslam, Tariq; Shakir, Savana; Murray, Clare

    2016-01-01

    IntroductionThe correct use of inhaler devices with facemasks and spacers in young children can be difficult for both children and parents, resulting in distress for both, poor adherence and ineffective drug delivery. The aim of this study was to develop and assess the utility and impact of an interactive electronic game designed to improve the experience of spacer devices in young asthmatic children.MethodsThe Respiratory Aid For Inhaler (RAFIhaler) technology consists of a smartphone mounte...

  4. EFFICIENCY IMPROVEMENT IN INDUSTRIAL BOILER BY FLUE GAS DUCT INSULATION

    OpenAIRE

    Sanjay H. Zala

    2017-01-01

    Now a days in industry major losses are find out so here we calculate these losses and find out efficiency of boiler. Boiler efficiency and energy losses from boiler are important parameter for any industry using boiler. In this work a detailed analysis was carried out for boiler at Anish Chemicals Bhavnagar. It is a combined water and fire tube boiler using biomass coal as fuel. Boiler efficiency calculated by direct method is in range of (78.5% to 81.6%). Major losses from boiler are heat ...

  5. Development of energy-saving devices for a full slow-speed ship through improving propulsion performance

    Directory of Open Access Journals (Sweden)

    Jung-Hun Kim

    2015-03-01

    Full Text Available Energy-saving devices for 317 K VLCC have been developed from a propulsion standpoint. Two ESD candidates were designed via computational tools. The first device WAFon composes of flow-control fins adapted for the ship wake to reduce the loss of rotational energy. The other is WAFon-D, which is a WAFon with a duct to obtain additional thrust and to distribute the inflow velocity on the propeller plane uniform. After selecting the candidates from the computed results, the speed performances were validated with model-tests. The hydrodynamic characteristics of the ESDs may be found in improved hull and propulsive efficiencies through increased wake fraction.

  6. Combined cycle power plants: technological prospects for improving the efficiency

    International Nuclear Information System (INIS)

    Lauri, R.

    2009-01-01

    The combined cycle power plants characteristics are better than one course open to a closed loop presenting an electrical efficiency close to 60% do not reach for gas turbine engines for power plants and conventional steam engines. [it

  7. An Improved, Highly Efficient Method for the Synthesis of Bisphenols

    Directory of Open Access Journals (Sweden)

    L. S. Patil

    2011-01-01

    Full Text Available An efficient synthesis of bisphenols is described by condensation of substituted phenols with corresponding cyclic ketones in presence of cetyltrimethylammonium chloride and 3-mercaptopropionic acid as a catalyst in extremely high purity and yields.

  8. Efficient Generation and Selection of Combined Features for Improved Classification

    KAUST Repository

    Shono, Ahmad N.

    2014-01-01

    This study contributes a methodology and associated toolkit developed to allow users to experiment with the use of combined features in classification problems. Methods are provided for efficiently generating combined features from an original

  9. Developing concepts for improved efficiency of robot work preparation

    OpenAIRE

    Essers, M.S.; Vaneker, Thomas H.J.

    2013-01-01

    SInBot[1] is a large research project that focuses on maximizing the efficient use of mobile industrial robots during medium sized production runs. The system that will be described in this paper will focusses on the development and validation of concepts for efficient work preparation for cells of intelligent mobile robots that execute medium sized production runs. For a wide range of products, the machining tasks will be defined on an appropriate level, enabling control over the robots beha...

  10. Fertigation for improved water use efficiency and crop yield

    International Nuclear Information System (INIS)

    Al-Wabel, M.I.; Al-Jaloud, A.A.; Hussain, G.; Karimulla, S.

    2002-01-01

    A greenhouse experiment was carried out at the Al-Muzahmiya Research Station, King Abdulaziz City for Science and Technology, Riyadh, to evaluate the effect of fertigation on cucumber yield. Five labelled N ( 15 N) treatments namely a control, soil application (120 mg N L -1 ), N-1 (60 mg N L -1 ), N-2 (120 mg N L -1 ) and N-3 (180 mg N L -1 ) were tried for their effect on greenhouse cucumber yield. A cucumber cultivar (Figaro F-1) was sown as test crop. The experiment was carried out during the period from April to July, 1997. The mean fresh fruit cucumber yield ranged between 7.73 to 33.74 t ha -1 . Highest yield was obtained with the labelled N application of 180 mg L -1 . The mean ranges for the different elements in the plant leaves were 1.33- 2.70% (N), 0.364-0.515% (P) and 1.57-3.82% (K). Whereas, in the plant shoot these ranges were 1.26-2.42% (N), 0.28-0.49% (P) and 4.74-9.45% (K). The mean content of the different elements in the cucumber fruit was 2.15-3.70% (N), 0.47-0.73% (P) and 4.40-5.23% (K). The soil salinity varied between 2.23-4.66 dS m -1 in the top soil (0-20 cm depth) and 0.95-2.62 dS m -1 in the sub-surface (20-40 cm depth) soil. The application did not affect significantly the soil salinity and was found well below the hazardous limit for most crops. The evolution of the other elements was different.. For example, elements such as Ca, P and K showed an increase while Na showed a decrease, whereas the Mg content did not respond with increasing N application. The soil moisture ranged between 8.06-9.15% (0-20 cm depth) and 5.51-9.36% (20-40 cm depth) and did not show any effect of N application. The nitrogen use efficiency (NUE) varied between 72.70 to 129.53 kg kg -1 N in the different N treatments. The mean 15 N a.e. ranged from 0.010 to 0.844% (leaves), 0.058 to 0.855% (shoots), 0.044 to 0.747 (roots) and 0.07 to 0.823 % (fruits). In conclusion, the mean highest yield of cucumber as fresh fruit was 33.74 t ha -1 , obtained with 180 mg N L

  11. IMPROVING CO2 EFFICIENCY FOR RECOVERING OIL IN HETEROGENEOUS RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Reid B. Grigg; Robert K. Svec; Zhengwen Zeng; Baojun Bai; Yi Liu

    2004-09-27

    The third annual report of ''Improving CO{sub 2} Efficiency for Recovery Oil in Heterogeneous Reservoirs'' presents results of laboratory studies with related analytical models for improved oil recovery. All studies were designed to optimize utilization and extend the practice of CO{sub 2} flooding to a wider range of reservoirs. Chapter 1 describes the behavior at low concentrations of the surfactant Chaser International CD1045{trademark} (CD) versus different salinity, pressure and temperature. Results of studies on the effects of pH and polymer (hydrolyzed polyacrylamide?HPAM) and CO{sub 2} foam stability after adsorption in the core are also reported. Calcium lignosulfonate (CLS) transport mechanisms through sandstone, description of the adsorption of CD and CD/CLS onto three porous media (sandstone, limestone and dolomite) and five minerals, and the effect of adsorption on foam stability are also reported. In Chapter 2, the adsorption kinetics of CLS in porous Berea sandstone and non-porous minerals are compared by monitoring adsorption density change with time. Results show that adsorption requires a much longer time for the porous versus non-porous medium. CLS adsorption onto sandstone can be divided into three regions: adsorption controlled by dispersion, adsorption controlled by diffusion and adsorption equilibrium. NaI tracer used to characterize the sandstone had similar trends to earlier results for the CLS desorption process, suggesting a dual porosity model to simulate flow through Berea sandstone. The kinetics and equilibrium test for CD adsorption onto five non-porous minerals and three porous media are reported in Chapter 3. CD adsorption and desorption onto non-porous minerals can be established in less than one hour with adsorption densities ranging from 0.4 to 1.2 mg of CD per g of mineral in decreasing order of montmorillonite, dolomite, kaolinite, silica and calcite. The surfactant adsorption onto three porous media takes

  12. Si Hybrid Solar Cells with 13% Efficiency via Concurrent Improvement in Optical and Electrical Properties by Employing Graphene Quantum Dots

    KAUST Repository

    Tsai, Meng Lin; Wei, Wan-Rou; Tang, Libin; Chang, Hung Chih; Tai, Shih Hsiang; Yang, Po Kang; Lau, Shu Ping; Chen, Lih Juann; He, Jr-Hau

    2015-01-01

    By employing graphene quantum dots (GQDs) in PEDOT:PSS, we have achieved an efficiency of 13.22% in Si/PEDOT:PSS hybrid solar cells. The efficiency enhancement is based on concurrent improvement in optical and electrical properties by the photon downconversion process and the improved conductivity of PEDOT:PSS via appropriate incorporation of GQDs. After introducing GQDs into PEDOT:PSS, the short circuit current and the fill factor of rear-contact optimized hybrid cells are increased from 32.11 to 36.26 mA/cm and 62.85% to 63.87%, respectively. The organic-inorganic hybrid solar cell obtained herein holds the promise for developing photon-managing, low-cost, and highly efficient photovoltaic devices.

  13. Si Hybrid Solar Cells with 13% Efficiency via Concurrent Improvement in Optical and Electrical Properties by Employing Graphene Quantum Dots

    KAUST Repository

    Tsai, Meng Lin

    2015-12-18

    By employing graphene quantum dots (GQDs) in PEDOT:PSS, we have achieved an efficiency of 13.22% in Si/PEDOT:PSS hybrid solar cells. The efficiency enhancement is based on concurrent improvement in optical and electrical properties by the photon downconversion process and the improved conductivity of PEDOT:PSS via appropriate incorporation of GQDs. After introducing GQDs into PEDOT:PSS, the short circuit current and the fill factor of rear-contact optimized hybrid cells are increased from 32.11 to 36.26 mA/cm and 62.85% to 63.87%, respectively. The organic-inorganic hybrid solar cell obtained herein holds the promise for developing photon-managing, low-cost, and highly efficient photovoltaic devices.

  14. A Process Improvement Evaluation of Sequential Compression Device Compliance and Effects of Provider Intervention.

    Science.gov (United States)

    Beachler, Jason A; Krueger, Chad A; Johnson, Anthony E

    This process improvement study sought to evaluate the compliance in orthopaedic patients with sequential compression devices and to monitor any improvement in compliance following an educational intervention. All non-intensive care unit orthopaedic primary patients were evaluated at random times and their compliance with sequential compression devices was monitored and recorded. Following a 2-week period of data collection, an educational flyer was displayed in every patient's room and nursing staff held an in-service training event focusing on the importance of sequential compression device use in the surgical patient. Patients were then monitored, again at random, and compliance was recorded. With the addition of a simple flyer and a single in-service on the importance of mechanical compression in the surgical patient, a significant improvement in compliance was documented at the authors' institution from 28% to 59% (p < .0001).

  15. Improving hemodynamics of cardiovascular system under a novel intraventricular assist device support via modeling and simulations.

    Science.gov (United States)

    Zhu, Shidong; Luo, Lin; Yang, Bibo; Li, Xinghui; Wang, Xiaohao

    2017-12-01

    Ventricular assist devices (LVADs) are increasingly recognized for supporting blood circulation in heart failure patients who are non-transplant eligible. Because of its volume, the traditional pulsatile device is not easy to implant intracorporeally. Continuous flow LVADs (CF-LVADs) reduce arterial pulsatility and only offer continuous flow, which is different from physiological flow, and may cause long-term complications in the cardiovascular system. The aim of this study was to design a new pulsatile assist device that overcomes this disadvantage, and to test this device in the cardiovascular system. Firstly, the input and output characteristics of the new device were tested in a simple cardiovascular mock system. A detailed mathematical model was established by fitting the experimental data. Secondly, the model was tested in four pathological cases, and was simulated and coupled with a fifth-order cardiovascular system and a new device model using Matlab software. Using assistance of the new device, we demonstrated that the left ventricle pressure, aortic pressure, and aortic flow of heart failure patients improved to the levels of a healthy individual. Especially, in state IV level heart failure patients, the systolic blood pressure increased from 81.34 mmHg to 132.1 mmHg, whereas the diastolic blood pressure increased from 54.28 mmHg to 78.7 mmHg. Cardiac output increased from 3.21 L/min to 5.16 L/min. The newly-developed assist device not only provided a physiological flow that was similar to healthy individuals, but also effectively improved the ability of the pathological ventricular volume. Finally, the effects of the new device on other hemodynamic parameters are discussed.

  16. Kinetic Monte Carlo modeling of the efficiency roll-off in a multilayer white organic light-emitting device

    NARCIS (Netherlands)

    Mesta, M.; van Eersel, H.; Coehoorn, R.; Bobbert, P.A.

    2016-01-01

    Triplet-triplet annihilation (TTA) and triplet-polaron quenching (TPQ) in organic light-emitting devices (OLEDs) lead to a roll-off of the internal quantum efficiency (IQE) with increasing current density J. We employ a kinetic Monte Carlo modeling study to analyze the measured IQE and color balance

  17. Device Performance and Reliability Improvements of AlGaBN/GaN/Si MOSFET

    Science.gov (United States)

    2016-02-04

    AFRL-AFOSR-JP-TR-2016-0037 Device Performance and Reliablity Improvements of AlGaBN/GaN/Si MOSFET Robert Wallace UNIVERSITY OF TEXAS AT DALLAS Final...GaN/Si MOSFET 5a.  CONTRACT NUMBER 5b.  GRANT NUMBER FA2386-14-1-4069 5c.  PROGRAM ELEMENT NUMBER 61102F 6. AUTHOR(S) Robert Wallace 5d.  PROJECT...AOARD Grant FA2386-14-1-4069 Device Performance and Reliability Improvements of AlGaN/GaN/Si MOSFET US 12 month extension (2014 – 2015) for current

  18. Efficient Use of Geothermal Energy in Spas - Call for Improvements

    Science.gov (United States)

    Straka, W.; Ponweiser, K.; Gollob, K.; Götzl, G.; Schneider, J. F.

    2009-04-01

    European partners contributed to the attempt to develop the energy flow calculation model designed for said spa into a numerical planning tool with broad applicability to other technical boundary conditions. This aim could not yet be fully achieved with the given means, by virtue of the fact that huge differences exist among spas, regarding technical design (sometimes accumulations of ad-hoc solutions to past technical problems) as well as characteristic energy demand of the various functional units of the investigated facilities. What could be achieved, though, was a better understanding how the communication between clients and consultants shall be conducted and what steps have to be taken in order to reach the original goal in a subsequent project. Furthermore, it was the ideational aim of our work to set up a network of established players, capable of influencing national developments, and make it a proponent of the envisaged improvements in their home countries and beyond. Among the recommended measures to improve on the energy management of existing thermal spas, on the one hand, there are those that only specialized knowledge can reveal or the proper application of which only painstaking monitoring and calculation can ascertain and which, therefore, will not easily be at the hand of many planners. These include, for example, combining geothermal heat with advanced heating technology (gas condensing boiler, cogeneration plant) for peak load conditions, deciding on the kind of advanced technology to be used (condensing boiler or cogeneration plus heat pump), making consistent said technology with the temperature control system (e.g. substitution of bypass design of heat exchanger control by volume flow control); introducing solar energy, in particular, has to be carefully designed. On the other hand, there are some improvements to be called for, which are meaningful and applicable even as belated additions, and in cases would, on top of this, be obvious to most non

  19. Energy efficiency improvements in electric motors and drives

    Energy Technology Data Exchange (ETDEWEB)

    Bertoldi, P. [Commission of the European Communities, Brussels (Belgium). Directorate General for Energy; Ameida, A.T. de [Coimbra Univ. (Portugal). Dept. de Engenharia Electrotecnica; Falkner, H. [eds.] [AEA Technolgy, Harwell (United Kingdom). ETSU

    2000-07-01

    This book covers the state of the art of energy-efficient electric motor technologies, which can be used now and in the near future to achieve significant and cost-effective energy savings. Recent developments in advanced motor technologies by some of the largest manufacturers of motors and drives are also presented. Although energy-efficient motor technologies can save a huge amount of electricity, they still have not been widely adopted. The barriers which can hinder the adoption of those technologies are presented. Policies and programmes to promote the large scale penetration of energy-efficient technologies and the market transformation are featured in the book, describing the experiences carried out in different parts of the world. This extensive coverage includes contributions from relevant institutions in the European Union, North America, Latin America, Japan, Australia and New Zealand. (orig.)

  20. Regional hospital improves efficiency with co-generation retrofit.

    Science.gov (United States)

    Knutson, D; Anderson, L

    1999-11-01

    Feasibility analysis of the co-generation retrofit of the Red Deer Regional Hospital pointed to a reasonable payback of capital cost and increased efficiency in operation of the facility. Budget restrictions nearly stopped the project from proceeding. Innovative construction procedures proposed by the Facility Management Group, in particular, Mr Keith Metcalfe, Director of Maintenance, allowed a worthwhile project to reach successful completion. We feel that this model can perhaps be used by similar facilities in the future to achieve their energy efficiency goals.

  1. A high-efficiency low-voltage CMOS rectifier for harvesting energy in implantable devices.

    Science.gov (United States)

    Hashemi, S Saeid; Sawan, Mohamad; Savaria, Yvon

    2012-08-01

    We present, in this paper, a new full-wave CMOS rectifier dedicated for wirelessly-powered low-voltage biomedical implants. It uses bootstrapped capacitors to reduce the effective threshold voltage of selected MOS switches. It achieves a significant increase in its overall power efficiency and low voltage-drop. Therefore, the rectifier is good for applications with low-voltage power supplies and large load current. The rectifier topology does not require complex circuit design. The highest voltages available in the circuit are used to drive the gates of selected transistors in order to reduce leakage current and to lower their channel on-resistance, while having high transconductance. The proposed rectifier was fabricated using the standard TSMC 0.18 μm CMOS process. When connected to a sinusoidal source of 3.3 V peak amplitude, it allows improving the overall power efficiency by 11% compared to the best recently published results given by a gate cross-coupled-based structure.

  2. Integration of quality improvement and cost-efficiency through industrial improvement techniques

    Directory of Open Access Journals (Sweden)

    Vink JP

    2016-06-01

    Full Text Available Jasper P Vink,1 Maxime T Rigaudy,1,2 Karl O Elmqvist11Imperial College Business School, Imperial College London, London, 2Hull York Medical School, York, UKIn this journal, Crema and Verbano1 discussed the importance of defining quality of health care and how quality can be improved through various industrial instruments and techniques. Quality of health care is a heavily debated topic that requires a wide scope of considerations across the many stakeholders of the health system. We acknowledge Crema and Verbano’s arguments that patient safety is a basic pillar of quality, upon which we would like to expand by highlighting the clinical effectiveness and patient-reported outcomes, which are the two further crucial components of quality. The arguments made regarding quality improvement techniques and cost efficiency in health care provision are insightful, yet appear to make a distinction between efforts to improve quality, eliminate waste from processes, and cut costs in health care provision. We would argue that in fact these achievements are all closely related and can be achieved simultaneously, if the industrial techniques of quality management are applied adequately.View the original paper by Crema and Verbano.

  3. Improving Farmers' Efficiency in Rice Production In Nigeria: The ...

    African Journals Online (AJOL)

    This paper assesses the effects of extension services on farmers' efficiency and productivity in rice production in Kano State, Nigeria. Data for the study were collected from 126 rice farmers selected using multi stage sampling technique. Stochastic production frontier function was estimated to ascertain the effects of ...

  4. Innovative financing for energy-efficiency improvements. Phase I report

    Energy Technology Data Exchange (ETDEWEB)

    Klepper, M.; Schwartz, H.K.; Feder, J.M.; Smith, D.C.; Green, R.H.; Williams, J.; Sherman, J.L.; Carroll, M.

    1982-01-01

    The use of utility-assisted financing, tax-exempt financing, bank financing, leasing, and joint venture financing to promote energy efficiency investments for each of three different categories of buildings (multifamily, commercial, and industrial) is discussed in separate chapters. (MCW)

  5. Improving the efficiency of deconvolution algorithms for sound source localization

    DEFF Research Database (Denmark)

    Lylloff, Oliver Ackermann; Fernandez Grande, Efren; Agerkvist, Finn T.

    2015-01-01

    of the unknown acoustic source distribution and the beamformer's response to a point source, i.e., point-spread function. A significant limitation of deconvolution is, however, an additional computational effort compared to beamforming. In this paper, computationally efficient deconvolution algorithms...

  6. Taxing energy to improve the environment : Efficiency and distributional effects

    NARCIS (Netherlands)

    Heijdra, BJ; van der Horst, A

    We study the effects of environmental tax policy in a dynamic overlapping generations model of a small open economy with environmental quality incorporated as a durable consumption good. Raising the energy tax may yield an efficiency gain if agents care enough about the environment. The benefits are

  7. Cambridge journals blog: Improving feed efficiency in dairy production

    Science.gov (United States)

    Because the cost of feeding animals is one of the greatest expenses in dairy production (40-60% of production costs), research focused on ways to identify and select for animals that are the most efficient at converting feed into milk has greatly expanded during the last decade. The animal Article o...

  8. ALTERNATIVES TO IMPROVE HYBRIDIZATION EFFICIENCY IN Eucalyptus BREEDING PROGRAMS

    Directory of Open Access Journals (Sweden)

    Roselaine Cristina Pereira

    2002-01-01

    Full Text Available Simple and quick hybridization procedures and ways to keep pollen grains viable for long periods are sought in plant breeding programs to provide greater work flexibility. The presentstudy was carried out to assess the efficiency of pollinations made shortly after flower emasculationand the viability of stored pollen from Eucalyptus camaldulensis and Eucalyptus urophylla clones cultivated in Northwestern Minas Gerais State. Controlled pollinations were carried out at zero, one,three, five and seven days after emasculation. Hybridization efficiency was assessed by thepercentage of viable fruits, number of seeds produced per fruit, percentage of viable seeds and also bycytological observation of the pollen development along the style. Flower buds from clones of the twospecies were collected close to anthesis to assess the viability of pollen grain storage. Pollen was thencollected and stored in a freezer (-18oC for 1, 2 and 3 months. Pollen assessed was carried out by invitro and in vivo germination tests. The efficiency of the pollinations varied with their delay and alsobetween species. The greatest pollination efficiency was obtained when they were carried out on thethird and fifth day after emasculation, but those performed simultaneously with emasculationproduced enough seeds to allow this practice in breeding programs. The decrease in pollen viabilitywith storage was not sufficiently significant to preclude the use of this procedure in artificialhybridization.

  9. Policies for improving energy efficiency in the European housing stock

    NARCIS (Netherlands)

    Sunikka, M.M.

    2006-01-01

    According to EC forecasts, if energy efficiency could be increased 1% annually until 2010, two-thirds of the potential energy saving in the EU could be achieved. This would comply with 40% of the EU's Kyoto obligation to reduce greenhouse gas emissions by 8% on the 1990 level by 2010-12, by cutting

  10. Design Strategies for Efficient Access to Mobile Device Users via Amazon Mechanical Turk

    OpenAIRE

    Jacques, Jason; Kristensson, Per Ola

    2017-01-01

    It is often challenging to access a pool of mobile device users and instruct them to perform an interactive task. Yet such data is often vital to provide design insight at various stages of the design process of a mobile application, service or system. We propose accessing a pool of mobile device users via the microtask market Amazon Mechanical Turk (MTurk). While mobile device users are still a minority on MTurk, they provide unique opportunities for requesters. Not only does catering to mob...

  11. Strategies for Improving siRNA-Induced Gene Silencing Efficiency.

    Science.gov (United States)

    Safari, Fatemeh; Rahmani Barouji, Solmaz; Tamaddon, Ali Mohammad

    2017-12-01

    Purpose: Human telomerase reverse transcriptase (hTERT) plays a crucial role in tumorigenesis and progression of cancers. Gene silencing of hTERT by short interfering RNA (siRNA) is considered as a promising strategy for cancer gene therapy. Various algorithms have been devised for designing a high efficient siRNA which is a significant issue in the clinical usage. Thereby, in the present study, the relation of siRNA designing criteria and the gene silencing efficiency was evaluated. Methods: The siRNA sequences were designed and characterized by using on line soft wares. Cationic co-polymer (polyethylene glycol-g-polyethylene imine (PEG-g-PEI)) was used for the construction of polyelectrolyte complexes (PECs) containing siRNAs. The cellular uptake of the PECs was evaluated. The gene silencing efficiency of different siRNA sequences was investigated and the effect of observing the rational designing on the functionality of siRNAs was assessed. Results: The size of PEG-g-PEI siRNA with N/P (Nitrogen/Phosphate) ratio of 2.5 was 114 ± 0.645 nm. The transfection efficiency of PECs was desirable (95.5% ± 2.4%.). The results of Real-Time PCR showed that main sequence (MS) reduced the hTERT expression up to 90% and control positive sequence (CPS) up to 63%. These findings demonstrated that the accessibility to the target site has priority than the other criteria such as sequence preferences and thermodynamic features. Conclusion: siRNA opens a hopeful window in cancer therapy which provides a convenient and tolerable therapeutic approach. Thereby, using the set of criteria and rational algorithms in the designing of siRNA remarkably affect the gene silencing efficiency.

  12. Efficiency of a gyroscopic device for conversion of mechanical wave energy to electrical energy

    DEFF Research Database (Denmark)

    Carlsen, Martin; Darula, Radoslav; Gravesen, Jens

    2011-01-01

    We consider a recently proposed gyroscopic device for conversion of mechanical ocean wave energy to electrical energy. Two models of the device derived from standard engineering mechanics from the literature are analysed, and a model is derived from analytical mechanics considerations. From...... these models, estimates of the power production, eciency, forces and moments are made. We nd that it is possible to extract a signicant amount of energy from an ocean wave using the described device. Further studies are required for a full treatment of the device....

  13. Measure of the volumetric efficiency and evaporator device performance for a liquefied petroleum gas spark ignition engine

    International Nuclear Information System (INIS)

    Masi, Massimo; Gobbato, Paolo

    2012-01-01

    Highlights: ► Measure of the effect of LPG fuel on volumetric efficiency of a SI petrol ICE. ► Steady-state and transient performance of a LPG evaporator device on a SI ICE. ► Volume displaced by LPG causes slight performance loss in SI petrol engines. ► LPG reveals peak efficiency and high-efficiency range wider than petrol in SI ICE’s. ► One-stage pressure reducer for LPG performs satisfactorily during SI ICE transients. - Abstract: The use of Liquefied Petroleum Gas (LPG) as fuel for spark ignition engines originally designed to be gasoline fuelled is common practice in many countries. Despite this, some questions remain still open. The present paper deals with the two main problems related to LPG port-fuel SI engines: the volumetric efficiency drop and the LPG evaporator device performance. A passengers car SI engine equipped with a “third generation” kit for the dual-fuel operation was tested using a dynamometer test rig. A single-stage pressure reducer was selected as LPG evaporator, to take advantage of an additional pre-heating of the liquid LPG that allows higher power output than a two-stage device of the same size. Engine performance, volumetric efficiency and change of LPG thermodynamic states in the evaporator were measured both in steady-state and transient operation of the engine. Steady-state measurements show the advantage of LPG in terms of engine efficiency, and quantify the drop in steady-state brake torque due to the volume swept by gaseous fuel in the fresh charge admission process. On the other hand, transient measurements show that a single-stage evaporator device is capable to match overall simplicity and satisfactory performance during strong changes in engine load.

  14. Enabling factors for the improvement of nitride-based LED efficiency

    International Nuclear Information System (INIS)

    Laubsch, Ansgar; Bergbauer, Werner; Sabathil, Matthias; Peter, Matthias; Meyer, Tobias; Bruederl, Georg; Linder, Norbert; Streubel, Klaus; Oberschmid, Raimund; Hahn, Berthold; Wagner, Joachim

    2008-01-01

    Recent progress in the epitaxial growth of LEDs with InGaN/GaN quantum-well heterostructures has led to a significant enhancement of output power. In this talk, we will discuss the mechanisms limiting the devices' internal efficiency and identify enabling factors for further improvements. We compare samples with different Indium content as well as different design of the active layer. Although heteroepitaxial growth of GaN on sapphire generates high defect densities, non-radiative defect-related Shockley-Read-Hall recombination does not seem to substantially limit the efficiency of standard InGaN/GaN LED structures. We rather discuss a supplemental Auger-like non-radiative path for carrier recombination that becomes dominant at quantum-well carrier densities typical for LED operation. Additionally, the piezo-field induced reduced overlap of electron and hole wavefunction in standard c-plane grown InGaN quantum wells reduces the radiative recombination rate

  15. A Game-Theoretical Approach for Spectrum Efficiency Improvement in Cloud-RAN

    Directory of Open Access Journals (Sweden)

    Zhuofu Zhou

    2016-01-01

    Full Text Available As tremendous mobile devices access to the Internet in the future, the cells which can provide high data rate and more capacity are expected to be deployed. Specifically, in the next generation of mobile communication 5G, cloud computing is supposed to be applied to radio access network. In cloud radio access network (Cloud-RAN, the traditional base station is divided into two parts, that is, remote radio heads (RRHs and base band units (BBUs. RRHs are geographically distributed and densely deployed, so as to achieve high data rate and low latency. However, the ultradense deployment inevitably deteriorates spectrum efficiency due to the severer intercell interference among RRHs. In this paper, the downlink spectrum efficiency can be improved through the cooperative transmission based on forming the coalitions of RRHs. We formulate the problem as a coalition formation game in partition form. In the process of coalition formation, each RRH can join or leave one coalition to maximize its own individual utility while taking into account the coalition utility at the same time. Moreover, the convergence and stability of the resulting coalition structure are studied. The numeric simulation result demonstrates that the proposed approach based on coalition formation game is superior to the noncooperative method in terms of the aggregate coalition utility.

  16. Optimized pulsed write schemes improve linearity and write speed for low-power organic neuromorphic devices

    Science.gov (United States)

    Keene, Scott T.; Melianas, Armantas; Fuller, Elliot J.; van de Burgt, Yoeri; Talin, A. Alec; Salleo, Alberto

    2018-06-01

    Neuromorphic devices are becoming increasingly appealing as efficient emulators of neural networks used to model real world problems. However, no hardware to date has demonstrated the necessary high accuracy and energy efficiency gain over CMOS in both (1) training via backpropagation and (2) in read via vector matrix multiplication. Such shortcomings are due to device non-idealities, particularly asymmetric conductance tuning in response to uniform voltage pulse inputs. Here, by formulating a general circuit model for capacitive ion-exchange neuromorphic devices, we show that asymmetric nonlinearity in organic electrochemical neuromorphic devices (ENODes) can be suppressed by an appropriately chosen write scheme. Simulations based upon our model suggest that a nonlinear write-selector could reduce the switching voltage and energy, enabling analog tuning via a continuous set of resistance states (100 states) with extremely low switching energy (~170 fJ · µm‑2). This work clarifies the pathway to neural algorithm accelerators capable of parallelism during both read and write operations.

  17. The improving efficiency frontier of religious not-for-profit hospitals.

    Science.gov (United States)

    Harrison, Jeffrey P; Sexton, Christopher

    2006-01-01

    By using data-envelopment analysis (DEA), this study evaluates the efficiency of religious not-for-profit hospitals. Hospital executives, healthcare policy makers, taxpayers, and other stakeholders benefit from studies that improve hospital efficiency. Results indicate that overall efficiency in religious hospitals improved from 72% in 1998 to 74% in 2001. What is more important is that the number of religious hospitals operating on the efficiency frontier increased from 40 in 1998 to 47 in 2001. This clearly documents that religious hospitals are becoming more efficient in the management of resources. From a policy perspective, this study highlights the economic importance of encouraging increased efficiency throughout the healthcare industry.

  18. Improving efficiencies of irrigation and nitrogen uptake in wheat

    International Nuclear Information System (INIS)

    Bazza, M.

    2000-01-01

    Three years of field studies and lysimeter experiments on irrigated wheat had the objective of finding ways of managing irrigation and N fertilization to minimize losses and reduce contamination of groundwater. Applied N had significant positive effects on crop-water consumptive use. The highest N losses occurred during early growth. Irrigation had little effect on N loss when it was practiced efficiently. Under the prevailing conditions, it is recommended that no N be applied to wheat at planting, in order to limit N losses by leaching caused by the high precipitation that usually occurs during early development when crop-N requirements are small. No more than 120 kg N ha -1 should be applied in total to minimize groundwater pollution and maximize N-uptake efficiency and economic returns. Also, for economic and environmental reasons, irrigation should be limited to 80% of the total requirement and to depths of 40 to 60 mm. (author)

  19. Evaluation and Improvement of Lighting Efficiency in Working Spaces

    OpenAIRE

    Ana Castillo-Martinez; Jose-Amelio Medina-Merodio; Jose-Maria Gutierrez-Martinez; Juan Aguado-Delgado; Carmen de-Pablos-Heredero; Salvador Otón

    2018-01-01

    Lighting is an essential element for modern life, promoting a sense of wellbeing for users. However, bad illumination may produce health problems such as headaches and fatigue, among other vision problems. For that reason, this paper proposes the development of a smartphone-based application to help in lighting evaluation to guarantee the compliance of illumination regulations and to help increase illuminance efficiency, reducing its energy consumption. To perform this evaluation, the smartph...

  20. Alternative Practices to Improve Surface Fleet Fuel Efficiency

    Science.gov (United States)

    2014-09-01

    through changes in procedures and operational modifications. iENCON uses BBLs/hr (barrels per hour) to evaluate the change in fuel efficiency (Pehlivan...policies and procedures that can be changed to continue the Navy’s efforts in the reduction of fuel consumption. Chapter III addresses drift...and four main engines. In a “full power” lineup all four engines are online. In a “split plant” lineup two engines remain online, one per shaft

  1. Efficiency of hydrogen peroxide in improving disinfection of ICU rooms.

    Science.gov (United States)

    Blazejewski, Caroline; Wallet, Frédéric; Rouzé, Anahita; Le Guern, Rémi; Ponthieux, Sylvie; Salleron, Julia; Nseir, Saad

    2015-02-02

    The primary objective of this study was to determine the efficiency of hydrogen peroxide (H₂O₂) techniques in disinfection of ICU rooms contaminated with multidrug-resistant organisms (MDRO) after patient discharge. Secondary objectives included comparison of the efficiency of a vaporizator (HPV, Bioquell) and an aerosolizer using H₂O₂, and peracetic acid (aHPP, Anios) in MDRO environmental disinfection, and assessment of toxicity of these techniques. This prospective cross-over study was conducted in five medical and surgical ICUs located in one University hospital, during a 12-week period. Routine terminal cleaning was followed by H₂O₂ disinfection. A total of 24 environmental bacteriological samplings were collected per room, from eight frequently touched surfaces, at three time-points: after patient discharge (T0), after terminal cleaning (T1) and after H₂O₂ disinfection (T2). In total 182 rooms were studied, including 89 (49%) disinfected with aHPP and 93 (51%) with HPV. At T0, 15/182 (8%) rooms were contaminated with at least 1 MDRO (extended spectrum β-lactamase-producing Gram-negative bacilli 50%, imipenem resistant Acinetobacter baumannii 29%, methicillin-resistant Staphylococcus aureus 17%, and Pseudomonas aeruginosa resistant to ceftazidime or imipenem 4%). Routine terminal cleaning reduced environmental bacterial load (P disinfection efficiency.

  2. Efficiency and safety of percuSurge distal protection device in acute ...

    African Journals Online (AJOL)

    user

    2011-04-25

    Apr 25, 2011 ... myocardial infarction. The long-term effects of the distal protection device are still in controversy. The enhanced myocardial efficacy and recovery by aspiration of liberated debris (EMERALD) trial failed to show the effectiveness of the distal protection device in patients with AMI (Yamada and Topol, 2000).

  3. Effectiveness of the stormwater quality devices to improve water quality at Putrajaya

    International Nuclear Information System (INIS)

    Sidek, L M; Basri, H; Puad, A H Mohd; Noh, M N Md; Ainan, A

    2013-01-01

    Development of Putrajaya has changed the character of the natural landform by covering the land with impervious surfaces. Houses, office buildings, commercial place and shopping centres have provided places to live and work. The route between buildings is facilitated and encouraged by a complex network of roads and car parks. However, this change from natural landforms and vegetative cover to impervious surfaces has major effect on stormwater which are water quality (non-point source pollution). This paper describes the effectiveness of the stormwater quality devices to improve water quality at selected Putrajaya for demonstration in order to evaluate low cost storm inlet type devices in the Putrajaya Catchment. Five stormwater quality devices were installed and monitored during the study. The devices include Ultra Drain Guard Recycle model, Ultra Curb Guard Plus, Ultra Grate Guard, Absorbent Tarp and Ultra Passive Skimmer. This paper will provide information on the benefits and costs of these devices, including operations and maintenance requirements. Applicability of these devices in gas stations, small convenience stores, residential and small parking lots in the catchment are possible due to their low cost.

  4. Utility of a simple lighting device to improve chest compressions learning.

    Science.gov (United States)

    González-Calvete, L; Barcala-Furelos, R; Moure-González, J D; Abelairas-Gómez, C; Rodríguez-Núñez, A

    2017-11-01

    The recommendations on cardiopulmonary resuscitation (CPR) emphasize the quality of the manoeuvres, especially chest compressions (CC). Audiovisual feedback devices could improve the quality of the CC during CPR. The aim of this study was to evaluate the usefulness of a simple lighting device as a visual aid during CPR on a mannequin. Twenty-two paediatricians who attended an accredited paediatric CPR course performed, in random order, 2min of CPR on a mannequin without and with the help of a simple lighting device, which flashes at a frequency of 100 cycles per minute. The following CC variables were analyzed using a validated compression quality meter (CPRmeter ® ): depth, decompression, rate, CPR time and percentage of compressions. With the lighting device, participants increased average quality (60.23±54.50 vs. 79.24±9.80%; P=.005), percentage in target depth (48.86±42.67 vs. 72.95±20.25%; P=.036) and rate (35.82±37.54 vs. 67.09±31.95%; P=.024). A simple light device that flashes at the recommended frequency improves the quality of CC performed by paediatric residents on a mannequin. The usefulness of this CPR aid system should be assessed in real patients. Copyright © 2017 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

  5. Improved Selectivity From a Wavelength Addressable Device for Wireless Stimulation of Neural Tissue

    Directory of Open Access Journals (Sweden)

    Elif Ç. Seymour

    2014-02-01

    Full Text Available Electrical neural stimulation with micro electrodes is a promising technique for restoring lost functions in the central nervous system as a result of injury or disease. One of the problems related to current neural stimulators is the tissue response due to the connecting wires and the presence of a rigid electrode inside soft neural tissue. We have developed a novel, optically activated, microscale photovoltaic neurostimulator based on a custom layered compound semiconductor heterostructure that is both wireless and has a comparatively small volume. Optical activation provides a wireless means of energy transfer to the neurostimulator, eliminating wires and the associated complications. This neurostimulator was shown to evoke action potentials and a functional motor response in the rat spinal cord. In this work, we extend our design to include wavelength selectivity and thus allowing independent activation of devices. As a proof of concept, we fabricated two different microscale devices with different spectral responsivities in the near-infrared region. We assessed the improved addressability of individual devices via wavelength selectivity as compared to spatial selectivity alone through on-bench optical measurements of the devices in combination with an in vivo light intensity profile in the rat cortex obtained in a previous study. We show that wavelength selectivity improves the individual addressability of the floating stimulators, thus increasing the number of devices that can be implanted in close proximity to each other.

  6. Pulsatile operation of a continuous-flow right ventricular assist device (RVAD) to improve vascular pulsatility.

    Science.gov (United States)

    Ng, Boon C; Kleinheyer, Matthias; Smith, Peter A; Timms, Daniel; Cohn, William E; Lim, Einly

    2018-01-01

    Despite the widespread acceptance of rotary blood pump (RBP) in clinical use over the past decades, the diminished flow pulsatility generated by a fixed speed RBP has been regarded as a potential factor that may lead to adverse events such as vasculature stiffening and hemorrhagic strokes. In this study, we investigate the feasibility of generating physiological pulse pressure in the pulmonary circulation by modulating the speed of a right ventricular assist device (RVAD) in a mock circulation loop. A rectangular pulse profile with predetermined pulse width has been implemented as the pump speed pattern with two different phase shifts (0% and 50%) with respect to the ventricular contraction. In addition, the performance of the speed modulation strategy has been assessed under different cardiovascular states, including variation in ventricular contractility and pulmonary arterial compliance. Our results indicated that the proposed pulse profile with optimised parameters (Apulse = 10000 rpm and ωmin = 3000 rpm) was able to generate pulmonary arterial pulse pressure within the physiological range (9-15 mmHg) while avoiding undesirable pump backflow under both co- and counter-pulsation modes. As compared to co-pulsation, stroke work was reduced by over 44% under counter-pulsation, suggesting that mechanical workload of the right ventricle can be efficiently mitigated through counter-pulsing the pump speed. Furthermore, our results showed that improved ventricular contractility could potentially lead to higher risk of ventricular suction and pump backflow, while stiffening of the pulmonary artery resulted in increased pulse pressure. In conclusion, the proposed speed modulation strategy produces pulsatile hemodynamics, which is more physiologic than continuous blood flow. The findings also provide valuable insight into the interaction between RVAD speed modulation and the pulmonary circulation under various cardiovascular states.

  7. Development of Pneumatic Aerodynamic Devices to Improve the Performance, Economics, and Safety of Heavy Vehicles

    International Nuclear Information System (INIS)

    Robert J. Englar

    2000-01-01

    Under contract to the DOE Office of Heavy Vehicle Technologies, the Georgia Tech Research Institute (GTRI) is developing and evaluating pneumatic (blown) aerodynamic devices to improve the performance, economics, stability and safety of operation of Heavy Vehicles. The objective of this program is to apply the pneumatic aerodynamic aircraft technology previously developed and flight-tested by GTRI personnel to the design of an efficient blown tractor-trailer configuration. Recent experimental results obtained by GTRI using blowing have shown drag reductions of 35% on a streamlined automobile wind-tunnel model. Also measured were lift or down-load increases of 100-150% and the ability to control aerodynamic moments about all 3 axes without any moving control surfaces. Similar drag reductions yielded by blowing on bluff afterbody trailers in current US trucking fleet operations are anticipated to reduce yearly fuel consumption by more than 1.2 billion gallons, while even further reduction is possible using pneumatic lift to reduce tire rolling resistance. Conversely, increased drag and down force generated instantaneously by blowing can greatly increase braking characteristics and control in wet/icy weather due to effective ''weight'' increases on the tires. Safety is also enhanced by controlling side loads and moments caused on these Heavy Vehicles by winds, gusts and other vehicles passing. This may also help to eliminate the jack-knifing problem if caused by extreme wind side loads on the trailer. Lastly, reduction of the turbulent wake behind the trailer can reduce splash and spray patterns and rough air being experienced by following vehicles. To be presented by GTRI in this paper will be results developed during the early portion of this effort, including a preliminary systems study, CFD prediction of the blown flowfields, and design of the baseline conventional tractor-trailer model and the pneumatic wind-tunnel model

  8. Development of Pneumatic Aerodynamic Devices to Improve the Performance, Economics, and Safety of Heavy Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Robert J. Englar

    2000-06-19

    Under contract to the DOE Office of Heavy Vehicle Technologies, the Georgia Tech Research Institute (GTRI) is developing and evaluating pneumatic (blown) aerodynamic devices to improve the performance, economics, stability and safety of operation of Heavy Vehicles. The objective of this program is to apply the pneumatic aerodynamic aircraft technology previously developed and flight-tested by GTRI personnel to the design of an efficient blown tractor-trailer configuration. Recent experimental results obtained by GTRI using blowing have shown drag reductions of 35% on a streamlined automobile wind-tunnel model. Also measured were lift or down-load increases of 100-150% and the ability to control aerodynamic moments about all 3 axes without any moving control surfaces. Similar drag reductions yielded by blowing on bluff afterbody trailers in current US trucking fleet operations are anticipated to reduce yearly fuel consumption by more than 1.2 billion gallons, while even further reduction is possible using pneumatic lift to reduce tire rolling resistance. Conversely, increased drag and down force generated instantaneously by blowing can greatly increase braking characteristics and control in wet/icy weather due to effective ''weight'' increases on the tires. Safety is also enhanced by controlling side loads and moments caused on these Heavy Vehicles by winds, gusts and other vehicles passing. This may also help to eliminate the jack-knifing problem if caused by extreme wind side loads on the trailer. Lastly, reduction of the turbulent wake behind the trailer can reduce splash and spray patterns and rough air being experienced by following vehicles. To be presented by GTRI in this paper will be results developed during the early portion of this effort, including a preliminary systems study, CFD prediction of the blown flowfields, and design of the baseline conventional tractor-trailer model and the pneumatic wind-tunnel model.

  9. LEAN SIX SIGMA TECHNIQUES TO IMPROVE OPHTHALMOLOGY CLINIC EFFICIENCY.

    Science.gov (United States)

    Ciulla, Thomas A; Tatikonda, Mohan V; ElMaraghi, Yehya A; Hussain, Rehan M; Hill, Amanda L; Clary, Julie M; Hattab, Eyas

    2017-07-18

    Ophthalmologists serve an increasing volume of a growing elderly population undergoing increasingly complex outpatient medical care, including extensive diagnostic testing and treatment. The resulting prolonged patient visit times ("patient flow times") limit quality, patient and employee satisfaction, and represent waste. Lean Six Sigma process improvement was used in a vitreoretinal practice to decrease patient flow time, demonstrating that this approach can yield significant improvement in health care. Process flow maps were created to determine the most common care pathways within clinic. Three months' visits from the electronic medical record system, which tracks patient task times at each process step in the office were collected. Care tasks and care pathways consuming the greatest time and variation were identified and modified. Follow-up analysis from 6 weeks' visits was conducted to assess improvement. Nearly all patients took one of five paths through the office. Patient flow was redesigned to reduce waiting room time by having staff members immediately start patients into one of those five paths; staffing was adjusted to address high demand tasks, and scheduling was optimized around derived predictors of patient flow times. Follow-up analysis revealed a statistically significant decline in mean patient flow time by 18% and inpatient flow time SD by 4.6%. Patient and employee satisfaction scores improved. Manufacturing industry techniques, such as Lean and Six Sigma, can be used to improve patient care, minimize waste, and enhance patient and staff satisfaction in outpatient clinics.

  10. Expected Improvements in Work Truck Efficiency Through Connectivity and Automation

    Energy Technology Data Exchange (ETDEWEB)

    Walkowicz, Kevin A [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2018-03-12

    This presentation focuses on the potential impact of connected and automated technologies on commercial vehicle operations. It includes topics such as the U.S. Department of Energy's Energy Efficient Mobility Systems (EEMS) program and the Systems and Modeling for Accelerated Research in Transportation (SMART) Mobility Initiative. It also describes National Renewable Energy Laboratory (NREL) research findings pertaining to the potential energy impacts of connectivity and automation and stresses the need for integration and optimization to take advantage of the benefits offered by these transformative technologies while mitigating the potential negative consequences.

  11. Improving efficiency of polystyrene concrete production with composite binders

    Science.gov (United States)

    Lesovik, R. V.; Ageeva, M. S.; Lesovik, G. A.; Sopin, D. M.; Kazlitina, O. V.; Mitrokhina, A. A.

    2018-03-01

    According to leading marketing researchers, the construction market in Russia and CIS will continue growing at a rapid rate; this applies not only to a large-scale major construction, but to a construction of single-family houses and small-scale industrial facilities as well. Due to this, there are increased requirements for heat insulation of the building enclosures and a significant demand for efficient walling materials with high thermal performance. All these developments led to higher requirements imposed on the equipment that produces such materials.

  12. Diphosphonic acid complexants for improved separation efficiency of transuranic elements

    International Nuclear Information System (INIS)

    Nash, K.L.

    1994-01-01

    A study was made of the thermodynamics of protonation and complexation of Eu(III), Th(IV), and U(VI) by a series of simple diphosphonic acid chelating agents to assess the potential for application in actinide waste processing. It was found that the strongest complexes are formed with ligands having two phosphonate binding groups on the same C atom (1,1-diphosphonates) and that the water-soluble complexes are formed with protonated ligand species. More efficient separation/recovery processes could be designed using these ligands

  13. Efficiency and reliability improvement in wind turbine converters by grid converter adaptive control

    DEFF Research Database (Denmark)

    Trintis, Ionut; Munk-Nielsen, Stig; Abrahamsen, Flemming

    2013-01-01

    This paper presents a control method that reduces the losses in wind turbine converters adaptively controlling the grid converter. The dc-link voltage adapts its reference based on the system state and therefore reduces the stored energy, and is therefore kept at the minimum necessary for the grid...... and generator side. Operating in this way, the electrical and thermal stress factors are decreased on the power electronic devices, increasing their lifetime. The simulation results using this method show efficiency increase and devices temperature cycles slightly decreased. Experimental results on a wind...... turbine power stack shows efficiency increase in the high power region....

  14. Electrical Stress Influences the Efficiency of CH3 NH3 PbI3 Perovskite Light Emitting Devices.

    Science.gov (United States)

    Zhao, Lianfeng; Gao, Jia; Lin, YunHui L; Yeh, Yao-Wen; Lee, Kyung Min; Yao, Nan; Loo, Yueh-Lin; Rand, Barry P

    2017-06-01

    Organic-inorganic hybrid perovskite materials are emerging as semiconductors with potential application in optoelectronic devices. In particular, perovskites are very promising for light-emitting devices (LEDs) due to their high color purity, low nonradiative recombination rates, and tunable bandgap. Here, using pure CH 3 NH 3 PbI 3 perovskite LEDs with an external quantum efficiency (EQE) of 5.9% as a platform, it is shown that electrical stress can influence device performance significantly, increasing the EQE from an initial 5.9% to as high as 7.4%. Consistent with the enhanced device performance, both the steady-state photoluminescence (PL) intensity and the time-resolved PL decay lifetime increase after electrical stress, indicating a reduction in nonradiative recombination in the perovskite film. By investigating the temperature-dependent characteristics of the perovskite LEDs and the cross-sectional elemental depth profile, it is proposed that trap reduction and resulting device-performance enhancement is due to local ionic motion of excess ions, likely excess mobile iodide, in the perovskite film that fills vacancies and reduces interstitial defects. On the other hand, it is found that overstressed LEDs show irreversibly degraded device performance, possibly because ions initially on the perovskite lattice are displaced during extended electrical stress and create defects such as vacancies. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Tracking truck flows with programmable mobile devices for drayage efficiency analysis: [research brief].

    Science.gov (United States)

    2016-05-01

    The purpose of this project is to design and experiment on a technology to track, organize, : extract and analyze data on port drayage activities from which a clear understanding of drayage : efficiency can be gained. Drayage efficiency may point to ...

  16. Efficiency improvement of variable speed electrical drives for HVAC applications

    Energy Technology Data Exchange (ETDEWEB)

    Abrahamsen, F.; Blaabjerg, F.; Pedersen, J.K. [Aalborg Univ., Inst. of Energy Technology, Aalborg East (Denmark)

    2000-07-01

    A large part of the produced electrical energy is consumed by ventilators, pumps and compressors, the so-called HVAC applications. A lot of this energy can be saved by speed control, but even with the large saving obtained alone by introduction of variable speed, it is still essential to optimise the control of the variable speed drive and to optimise the electrical machine with respect to efficiency. Experiments are made with energy optimal induction motor control on a 2.2 kW variable speed pump system. It is demonstrated that 10% of the consumed energy can typically be saved by energy optimal motor control compared with constant V/Hz control. In a comparison of induction motors and permanent magnet synchronous motors for a variable speed pump application it is shown that for 2.2 kW motors an investment in high-efficiency or PM motors are typically paid back within 2.5 years and 7 years respectively. For a 90 kW PM motor the pay-back time would be 24 years. It is today not profitable to use PM motors for variable speed HVAC applications above 2 kW rated motor power. A further study is required to determine this limit in power rating more precisely. (orig.)

  17. Nuclear turbine efficiency improvement by wet steam study

    International Nuclear Information System (INIS)

    Nishikawa, Tsuyoshi; Morson, A.; Markytan, R.

    2000-01-01

    Most of the turbine used at the nuclear power plant are operated at environment of wet steam, which composes of a big factor of its inner loss in comparison with those of the thermal power plant. If an analytical method predictable on behavior of the wet steam is established, it could be upgraded efficiency of the turbine and also reliability against corrosion formed by moisture. This study, therefore, aims at understanding of physical property of the wet steam flow scarcely known at present, development of an optimum turbine cascade design tool reflected by the property, development of a turbine cascade design reducible of steam loss due to wet steam by using the tool, and development on a method of removing moisture in the turbine to its outer portion. For the tool, a new three dimensional flow numerical analysis is necessary to be developed, to aim at accurately and numerically understanding of the behavior of wet steam. As this study is in advancing now, by using a turbine cascade optimized on the wet steam flow and a developed moisture removing apparatus, about 0.6 % of upgrading in turbine efficiency can be predicted in comparison with that of the advanced aero-cascade of the GE Corporation. (G.K.)

  18. Layout design in order to improve efficiency in manufacturing

    Science.gov (United States)

    Siregar, I.; Tarigan, U.; Nasution, T. H.

    2018-02-01

    This research was conducted at the company that produces bobbins and ream type cigarette paper. Problems that found on the production process is the back and forth (back tracking) movement. Back and forth (back tracking) movement extending the total distance moved by the material and increase the total moment of transfer materials thus reducing the efficiency of the transfer of materials in the production process. The purpose of this study is to give design for the layout of production facilities in the company, so that the expected production produced by the company can reach the targets set by the management company. The method used in this research is the Graph-Based Construction and Travel Chart Method. The results of the analysis of the proposed layout with Graph-Based Construction was selected with a total value that is equal to the moment of transfer of 780 758 m / year. This result is better than the actual layout in the amount of 1,021,038.12 meters / year and the results of the method Travel Alternative Chart I of 826.236,60 meters/year, Alternative II of 1.004.433,56 meters / year, and Alternative III for 828,467.12 meters/year. The design layout of Graph-Based Construction material increases the transfer efficiency for 23.53%. With this layout proposal, expected production capacity will be increased along with the shortening of the distance of the displacement that must be passed by the material to be processed.

  19. Improvement of operational efficiency based on fast startup plant concepts

    Energy Technology Data Exchange (ETDEWEB)

    Kurz, Harald; Meinecke, Gero; Ohresser, Sylvia; Pickard, Andreas

    2010-09-15

    One of the major global challenges of the present time is the reduction of CO2 emissions. Provisions for integration of a CO2 capture plant are already required today in new power plant construction projects in order to enable current plants to also benefit from the possibilities of carbon capture systems to be developed in the future. These provisions for integration should account for the fact that the scrubbing processes are still in the optimization phase. Requisite process parameters may still change in the future. In the development of a plant interface, the paper describes a concept developed by Siemens which ensures maximum flexibility with simultaneous optimization of the plant for the capture process. Emphasis was placed on the following points in the development of this interface and the associated connection concepts: Maximum plant efficiency before and after modification; Maximum flexibility with regard to future process parameters; Optimization of customer investment cash flow; and, Applicability also to existing plants. According to the paper, Siemens can offer a concept which enables future conversion in accordance with the specified criteria. This concept requires no compromises with regard to plant efficiency in process optimization for either current power plant operation without carbon capture or for future operation with carbon capture. The concept also enables retrofitting of existing plants which are not yet capture-ready. However, retrofitting of power plants which are not prepared for operation with carbon capture is considerably more elaborate in most cases, as corridors must frequently still be cleared for the connecting piping.

  20. System solution to improve energy efficiency of HVAC systems

    Science.gov (United States)

    Chretien, L.; Becerra, R.; Salts, N. P.; Groll, E. A.

    2017-08-01

    According to recent surveys, heating and air conditioning systems account for over 45% of the total energy usage in US households. Three main types of HVAC systems are available to homeowners: (1) fixed-speed systems, where the compressor cycles on and off to match the cooling load; (2) multi-speed (typically, two-speed) systems, where the compressor can operate at multiple cooling capacities, leading to reduced cycling; and (3) variable-speed systems, where the compressor speed is adjusted to match the cooling load of the household, thereby providing higher efficiency and comfort levels through better temperature and humidity control. While energy consumption could reduce significantly by adopting variable-speed compressor systems, the market penetration has been limited to less than 10% of the total HVAC units and a vast majority of systems installed in new construction remains single speed. A few reasons may explain this phenomenon such as the complexity of the electronic circuitry required to vary compressor speed as well as the associated system cost. This paper outlines a system solution to boost the Seasonal Energy Efficiency Rating (SEER) of a traditional single-speed unit through using a low power electronic converter that allows the compressor to operate at multiple low capacity settings and is disabled at high compressor speeds.