WorldWideScience

Sample records for alternating current systems

  1. Electromechanical systems generating constant frequency alternating current

    Directory of Open Access Journals (Sweden)

    Т.А. Мазур

    2008-01-01

    Full Text Available  In the article we consider the usage of electromechanical drivers of constant speed rotation, which is based on many stepped electrodynamic reduction unit, in onboard main systems of electric supply of alternative current with constant frequency.

  2. Alternating current electrospinning for preparation of fibrous drug delivery systems.

    Science.gov (United States)

    Balogh, Attila; Cselkó, Richárd; Démuth, Balázs; Verreck, Geert; Mensch, Jürgen; Marosi, György; Nagy, Zsombor Kristóf

    2015-11-10

    Alternating current electrospinning (ACES) was compared to direct current electrospinning (DCES) for the preparation of drug-loaded nanofibrous mats. It is generally considered that DCES is the solely technique to produce nanofibers using the electrostatic force from polymer solutions, however, less studied and also capable ACES provides further advantages such as increased specific productivities. A poorly water-soluble drug (carvedilol) was incorporated into the fibers based on three different polymeric matrices (an acid-soluble terpolymer (Eudragit(®) E), a base-soluble copolymer (Eudragit(®) L 100-55) and a nonionic homopolymer (polyvinylpyrrolidone K90)) to improve the dissolution of the weak base drug under different pH conditions. Morphology and fiber diameter evaluation showed similar electrospun fibers regardless the type of the high voltage and the major differences in feeding rates. The amorphous ACES and DCES fibers provided fast and total drug dissolutions in all cases. The presented results show that ACES can be a more feasible novel alternative to formulate fibers for drug delivery purposes. PMID:26320549

  3. Alternating Current All-electrical Gun Control System in Tanks

    Directory of Open Access Journals (Sweden)

    Zang Kemao

    2004-07-01

    Full Text Available The ac all-electrical gun control system is composed of permanent magnetic synchronous machine-drive control systems and the ball-screw by replacing the complicated electrohydraulic systems. At the same time, the variable-structure system with sliding modes makes the gun control systems to have higher performances using the only rate flexure gyroscope. Thereby, vehicle hull gyroscope and angular gyroscope are left out.The new ac all-electrical gun control systems developed are reduced by 40 per cent in weight, decreased by 30 per cent in volume, increased by 35 per cent in efficiency, and enhanced by three times in service life as compared to the current gun control systems.

  4. Alternating Current All-electrical Gun Control System in Tanks

    OpenAIRE

    Zang Kemao; Ma Xiaojun; Li Changbing

    2004-01-01

    The ac all-electrical gun control system is composed of permanent magnetic synchronous machine-drive control systems and the ball-screw by replacing the complicated electrohydraulic systems. At the same time, the variable-structure system with sliding modes makes the gun control systems to have higher performances using the only rate flexure gyroscope. Thereby, vehicle hull gyroscope and angular gyroscope are left out.The new ac all-electrical gun control systems developed are reduced by 40 p...

  5. Methods, systems and apparatus for controlling operation of two alternating current (AC) machines

    Science.gov (United States)

    Gallegos-Lopez, Gabriel; Nagashima, James M.; Perisic, Milun; Hiti, Silva

    2012-06-05

    A system is provided for controlling two alternating current (AC) machines via a five-phase PWM inverter module. The system comprises a first control loop, a second control loop, and a current command adjustment module. The current command adjustment module operates in conjunction with the first control loop and the second control loop to continuously adjust current command signals that control the first AC machine and the second AC machine such that they share the input voltage available to them without compromising the target mechanical output power of either machine. This way, even when the phase voltage available to either one of the machines decreases, that machine outputs its target mechanical output power.

  6. A new system of alternating current motors and transformers and other essays

    CERN Document Server

    Tesla, Nikola

    2013-01-01

    Nikola Tesla was a genius who revolutionized how the world looks at electricity. During college his professors explained that it was impossible to design an engine without commutators or brushes. Tesla was unconvinced that such was necessary or even particularly desirable. It was then that Tesla began his work on the rotating field motor that ultimately gave birth to the modern age. In May of 1888, Tesla delivered his lecture ""A New System of Alternating Current Motors and Transformers"" before The American Institute of Electrical Engineers and the world has never been the same.

  7. Research on the variable speed system of large power alternating current motor%Research on the variable speed system of large power alternating current motor

    Institute of Scientific and Technical Information of China (English)

    Li Chongjian

    2012-01-01

    The development status of the variable speed system of large power AC (alternating current) motor drive in China is introduced. The large power AC drive fed by AC-AC converters (cycloconverters) has developed greatly, and some innovations on the theory and engineering technique have been realized. They have been applied to rolling mills, mine hoists, and so on, and remarkable economic and social benefit has been achieved. The development of AC drive fed by large power IGCT (integrated gate commutated thyristors) AC-DC-AC converter is also introduced. It has excellent performance and reliable operation, and has been used in traction.

  8. Improvement of immunoassay detection system by using alternating current magnetic susceptibility

    Science.gov (United States)

    Kawabata, R.; Mizoguchi, T.; Kandori, A.

    2016-03-01

    A major goal with this research was to develop a low-cost and highly sensitive immunoassay detection system by using alternating current (AC) magnetic susceptibility. We fabricated an improved prototype of our previously developed immunoassay detection system and evaluated its performance. The prototype continuously moved sample containers by using a magnetically shielded brushless motor, which passes between two anisotropic magneto resistance (AMR) sensors. These sensors detected the magnetic signal in the direction where each sample container passed them. We used the differential signal obtained from each AMR sensor's output to improve the signal-to-noise ratio (SNR) of the magnetic signal measurement. Biotin-conjugated polymer beads with avidin-coated magnetic particles were prepared to examine the calibration curve, which represents the relation between AC magnetic susceptibility change and polymer-bead concentration. For the calibration curve measurement, we, respectively, measured the magnetic signal caused by the magnetic particles by using each AMR sensor installed near the upper or lower part in the lateral position of the passing sample containers. As a result, the SNR of the prototype was 4.5 times better than that of our previous system. Moreover, the data obtained from each AMR sensor installed near the upper part in the lateral position of the passing sample containers exhibited an accurate calibration curve that represented good correlation between AC magnetic susceptibility change and polymer-bead concentration. The conclusion drawn from these findings is that our improved immunoassay detection system will enable a low-cost and highly sensitive immunoassay.

  9. Analysis of operations and cyber security policies for a system of cooperating Flexible Alternating Current Transmission System (FACTS) devices.

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, Laurence R.; Tejani, Bankim; Margulies, Jonathan; Hills, Jason L.; Richardson, Bryan T.; Baca, Micheal J.; Weiland, Laura

    2005-12-01

    Flexible Alternating Current Transmission Systems (FACTS) devices are installed on electric power transmission lines to stabilize and regulate power flow. Power lines protected by FACTS devices can increase power flow and better respond to contingencies. The University of Missouri Rolla (UMR) is currently working on a multi-year project to examine the potential use of multiple FACTS devices distributed over a large power system region in a cooperative arrangement in which the FACTS devices work together to optimize and stabilize the regional power system. The report describes operational and security challenges that need to be addressed to employ FACTS devices in this way and recommends references, processes, technologies, and policies to address these challenges.

  10. New algorithm to detect voltage disturbances in three phases alternative current systems

    Energy Technology Data Exchange (ETDEWEB)

    Benslimane, T.; Chetate, B. [University of Boumerdes (Algeria)

    2006-07-01

    In this paper is presented a new algorithm based on logical functions to detect different disturbances in alternative voltage in electrical power networks such as over-voltage, under-voltage, unbalanced voltage, short circuit besides the safe operating condition. This algorithm is based on RMS values of three phases voltages as input values to detection system that is basically based on logical functions. This system is applied on three phase electrical power network of sinusoidal voltage. It can also be applied on PWM voltage that must be filtered to get its fundamental RMS value. Simulation program was developed in Matlab/Simulinksoftware. Simulation results are presented. (orig.)

  11. ALTERNATING CURRENT ELECTROCOAGULATION FOR SUPERFUND SITE REMEDIATION

    Science.gov (United States)

    The technical and economical feasibility of alternating current electrocoagulation (ACE) developed by Electro-Pure Systems, Inc., was evaluated for a 2-year period. CE is an electrochemical technology where highly-charged aluminum polyhydroxide species are introduced into aqueous...

  12. Choice Of Input Data Type Of Artificial Neural Network To Detect Faults In Alternative Current Systems

    Directory of Open Access Journals (Sweden)

    T. Benslimane

    2006-01-01

    Full Text Available This paper present a study on different input data types of ANN used to detect faults such as over-voltage in AC systems (AC network , induction motor. The input data of ANN are AC voltage and current. In no fault condition, voltage and current are sinusoidal. The input data of the ANN may be the instantaneous values of voltage and current, their RMS values or their average values after been rectified. In this paper we presented different characteristics of each one of these data. A digital software C++ simulation program was developed and simulation results were presented.

  13. Development of alternating current transmitter of detection system for magnetic material in soil subsurface

    Science.gov (United States)

    Indrasari, Widyaningrum; Djamal, Mitra; Srigutomo, Wahyu; Ramli

    2016-03-01

    Generally, detection system for magnetic material in soil subsurface using electromagnetic induction method consists of two parts, they are transmitter and receiver unit. A transmitter must be able to produce a continuous and stable AC current at a certain frequency, meanwhile receiver should be able to catch the secondary magnetic field of magnetic material in soil subsurface. The aim of this study was to develop a new AC current transmitter of detection system for the magnetic material in soil subsurface. This paper will describe the results of the development of AC current transmitter systems, distance characterization of the sensor detection toward horizontal solenoid positions, and characterization of magnetic material in the soil subsurface. It has successfully made the AC current transmitter system, composed of a sinusoidal signal generator, power amplifier, and a source of AC magnetic field. The output of the generator has a frequency varies: 1 kHz, 2 kHz, 5 kHz, and 10 kHz. We found that the AC current transmitter that has been developed able to work properly up to a frequency of 10 kHz.

  14. Optimal power flow tool for mixed highvoltage alternating current and high-voltage direct current systems for grid integration of large wind power plants

    OpenAIRE

    Aragüés Peñalba, Mònica; Egea Àlvarez, Agustí; Galcerán Arellano, Samuel; Gomis Bellmunt, Oriol

    2015-01-01

    This study presents a tool for solving optimal power flows (OPFs) in hybrid high-voltage direct current (HVDC) and high-voltage alternating current (HVAC) systems for grid integration of large wind power plants, located either offshore or onshore. The OPF departs from the assumption that the power being produced from the wind power plants is known, as well as the demand from the AC grid. To model the interaction between the DC and AC grids, the active power conservation is expressed between t...

  15. Potential for using a six-phase alternating current power supply system for in situ vitrification

    International Nuclear Information System (INIS)

    In situ vitrification (ISV) has been identified as a potential treatment technology for stabilizing underground tanks at Hanford and other US Department of Energy (DOE) sites. A key requirement for this application is an electrical system that can supply the power needed to vitrify a tank in a single setting. This paper describes an engineering-scale test conducted at the Pacific Northwest Laboratory (PNL) to assess the efficiency of a six-electrode, six-phase energy supply system in melting soil. The test was conducted with a 30-kW six-phase system. Based on the test results, a six-electrode, six-phase system shows potential for scaleup to larger systems. 5 refs., 5 figs., 2 tabs

  16. Alternating current for the West

    International Nuclear Information System (INIS)

    In the framework of the reactor EPR construction in the Manche, the authors wonder on the pertinence of this energy choice for the economy and the environment of the West France. They show that there is an alternative to this choice. In a first part a state of the situation concerning the electricity supply and demand in the region is detailed. Then from the local potential of renewable electric power production and the electricity conservation, they propose many concrete actions. (A.L.B.)

  17. In situ measurement of alternating current magnetic susceptibility of Pd-hydrogen system for determination of hydrogen concentration in bulk

    Science.gov (United States)

    Akamaru, Satoshi; Hara, Masanori; Matsuyama, Masao

    2012-07-01

    An alternating current magnetic susceptometer for use as a hydrogen gauge for hydrogen-storage materials was designed and developed. The experimental system can simultaneously measure the hydrogen equilibrium pressure and the magnetic susceptibility of metal hydrides. The background voltage of the susceptometer was stabilized for a long period of time, without any adjustments, by attaching an efficient compensation circuit. The performance of the susceptometer at a static hydrogen concentration was demonstrated by measuring the magnetic susceptibility of a Pd-hydrogen system under equilibrium conditions. The in situ measurement of the magnetic susceptibility of Pd during hydrogen absorption was carried out using the susceptometer. Since the in situ magnetic susceptibility obtained at a lower initial hydrogen pressure agreed with the magnetic susceptibility measured at a static hydrogen concentration, the susceptometer could be used to determine the hydrogen concentration in Pd in situ. At a higher initial hydrogen pressure, enhancement of the magnetic susceptibility was observed at the beginning of hydrogen absorption because the magnetic moments induced by the large temporary strain generated in the Pd affected the magnetic susceptibility.

  18. Alternating current electrocoagulation for Superfund site remediation

    International Nuclear Information System (INIS)

    A study is being conducted by Electro-Pure Systems, Inc. (EPS) under the Emerging Technology portion of the U.S. Environmental Protection Agency's (EPA's) Superfund Innovative Technology Evaluation (SITE) Program to study alternating current electrocoagulation for Superfund site remediation. Alternating current electrocoagulation has proven to be effective in agglomerating and removing colloidal solids, metals and certain organic contaminants from surrogate soils prepared from the US EPA's Synthetic Soil Matrix. Treatments under a wide range of operating conditions have enabled the optimum parameter settings to be established for multiple phase separation. Electrocoagulation enables appreciably enhanced filtration and dewatering rates to be realized for metals- and diesel fuel-spiked surrogate soil slurries; such enhancements are prompted by growth in the mean particle size of the clays and particulates from typically < 10 microns to as much as 150 microns depending on the degree of electrocoagulation. Reduction in the total suspended solids content of clays in all slurries in excess of 90% can routinely be achieved. Bench-scale experiments of the metals-spiked surrogate soils indicate that electrocoagulation preferentially concentrates soluble metals into the sludge phase; excellent metals separation (Pb, Cr, Cu, Cd) can be realized. Experiments on surrogate wastes spiked with volatile organics suggest that this technology is not capable of effecting good volatile extractions from the aqueous phase. Reductions in excess of 80% in the total organic carbon (TOC) content of the diesel fuel-spiked surrogates can, however, be achieved

  19. Stability of alternating current gliding arcs

    DEFF Research Database (Denmark)

    Kusano, Yukihiro; Salewski, Mirko; Leipold, Frank;

    2014-01-01

    on Ohm’s law indicates that the critical length of alternating current (AC) gliding arc discharge columns can be larger than that of a corresponding direct current (DC) gliding arc. This finding is supported by previously published images of AC and DC gliding arcs. Furthermore, the analysis shows...

  20. Direct Current Contamination of Kilohertz Frequency Alternating Current Waveforms

    OpenAIRE

    Franke, Manfred; Bhadra, Niloy; Bhadra, Narendra; Kilgore, Kevin

    2014-01-01

    Kilohertz Frequency Alternating Current (KHFAC) waveforms are being evaluated in a variety of physiological settings because of their potential to modulate neural activity uniquely when compared to frequencies in the sub-kilohertz range. However, the use of waveforms in this frequency range presents some unique challenges regarding the generator output. In this study we explored the possibility of undesirable contamination of the KHFAC waveforms by direct current (DC). We evaluated current- a...

  1. Charging unit for magnetic system of the JINR collective accelerator power supply on the base of alternating current thyristor converter

    International Nuclear Information System (INIS)

    The described charging unit of the capacity store for magnetic system of the JINR collective accelerator is intended for recharging capacitor battery energy loss value in a discharge circuit for the time not exceeding 10 ms. The developed system of automatic voltage control (AVC) for the charging unit ensures operating frequency up to 20-40 Hz, and permits to realize voltage stabilization of the capacitor battery. The three-phase thyristor converter at the inlet of the step-up trasformer of the charging unit controllable by means of the central data handing processing unit GZ 800 (development and fabrication of the GDR) is used. The experimentally measured summarized constant of time of the systems with AVC is 5-8 ms, maximum voltage at the battery of the 100 μF capacity at the frequency of 20 Hz-17.5 kV. The average magnitude of the charge current in the given regime has attained 7A. The charging unit working ability at the frequency of 20 Hz and the 5 kA discharge current has been verified

  2. Enhancing liquid-liquid and solid-liquid phase separation by integrating alternating current electrocoagulators with processing and wastewater control systems

    International Nuclear Information System (INIS)

    Coal, pigments, pharmaceutical solids, ceramics, carbon, clays, metallic powders and ores are among the categorical groups of products which are wasted as suspended solids in aqueous-based wash solutions. Phase separation and recovery of these solids by conventional dewatering systems is costly and relatively inefficient. Alternating current can be used to neutralize the electrical charge on fine and ultra-fine particles in aqueous suspensions, and facilitate agglomeration and settling of these particulates without using chemicals while improving recovery efficiencies. This paper provides an overview of the technology and discusses applications and benefits in the areas of in-plant processing, industrial wastewater treatment, site remediation and water purification

  3. Tiling by rectangles and alternating current

    KAUST Repository

    Prasolov, M. V.

    2011-04-01

    This paper is on tilings of polygons by rectangles. A celebrated physical interpretation of such tilings by R.L. Brooks, C.A.B. Smith, A.H. Stone and W.T. Tutte uses direct-current circuits. The new approach of this paper is an application of alternating-current circuits. The following results are obtained: •a necessary condition for a rectangle to be tilable by rectangles of given shapes;•a criterion for a rectangle to be tilable by rectangles similar to it but not all homothetic to it;•a criterion for a "generic" polygon to be tilable by squares. These results generalize those of C. Freiling, R. Kenyon, M. Laczkovich, D. Rinne, and G. Szekeres. © 2010 Elsevier Inc.

  4. Alternate transportation system

    Science.gov (United States)

    Zertuche, Tony; Mckinnie, James

    1988-01-01

    Three missions have been identified by NASA for a Space Shuttle-supplementing Alternate Transportation System (ATS) encompassing combinations of booster vehicles, crew modules, and service modules: (1) to achieve manned access to orbit for Space Station crew rotation every 90 days, (2) the lofting of a logistics module resupplying the Space Station every 180 days, and (3) the simultaneous launch of both crews and logistics to the Space Station. A reentry glider is considered, in conjunction with the Space Shuttle's unmanned cargo version and the Apollo manned capsule, as an important ATS element. The Titan IV/NUS is used as a booster.

  5. Overview of current and alternative slaughter practices

    Directory of Open Access Journals (Sweden)

    Troeger K.

    2004-01-01

    Full Text Available The conventional cattle slaughtering process includes some critical stages where a dissemination of Specified Risk Material (SRM: brain, spinal cord within or onto the carcass and within the slaughterhouse environment can occur. These processes are captive bolt stunning, removal of the head and first of all carcass splitting (sawing the spine lengthways. Captive bolt (CB stunning results in massive brain tissue damage with bleeding, and in some cases brain tissue also emerges from the CB hole. As the heart is still functioning, there is a risk of brain tissue particles being transferred v i a the blood flow to heart and lungs or even in the whole carcass. This contamination risk is actually assessed to be low, but a continuing leakage of Central Nervous System (CNS material from the captive bolt aperture in the further slaughter process may lead to direct and indirect contamination of carcass, meat and equipment. Therefore alternative stunning methods like electrical stunning or concussion stunning are discussed. A further critical point is the treatment of the head. When the head is removed, the spinal cord is cut with a knife. There is a danger of cross contamination due to spinal protein that may adhere to the knife and because of liquid cerebralis, which leaks from the foramen occipitale magnum. Further head cleaning with hand-held hoses following skinning also includes the danger of cross contamination from cleaning water or aerosol. Therefore measures regarding the safe handling of head and harvesting of head meat are proposed. The most critical point in terms of contamination of the meat surface with SRM is the currently common practise of sawing the spine vertically in the middle with hand-guided belt-type saws. A m i x t u r e of sawing residues and rinsing water (“sawing sludge” collects in the housing of the saw, and if it contains infectious material this leads to contamination of the subsequent carcasses. The most promising

  6. Application of Adaptive Backstepping Sliding Mode Control in Alternative Current Servo System of Rocket Launcher%Application of Adaptive Backstepping Sliding Mode Control in Alternative Current Servo System of Rocket Launcher

    Institute of Scientific and Technical Information of China (English)

    郭亚军; 马大为; 王晓峰; 乐贵高

    2011-01-01

    An adaptive backstepping sliding mode control approach is introduced to control the pitch motion of a rocket launcher. Its control law is proposed to guarantee that the control system is ultimately bounded in a Lyapunov sense and make the servo system track the instruction of reference position globally and asymptotically. In addition, the sliding mode control can restrain the effects of parameter uncertainties and external disturbance. The functions of adaptive mechanism and sliding mode control are analyzed through the simulation in the different conditions. The simulation results illustrate that the method is applicable and robust.

  7. Alternating Current Influences Anaerobic Electroactive Biofilm Activity.

    Science.gov (United States)

    Wang, Xin; Zhou, Lean; Lu, Lu; Lobo, Fernanda Leite; Li, Nan; Wang, Heming; Park, Jaedo; Ren, Zhiyong Jason

    2016-09-01

    Alternating current (AC) is known to inactivate microbial growth in suspension, but how AC influences anaerobic biofilm activities has not been systematically investigated. Using a Geobacter dominated anaerobic biofilm growing on the electrodes of microbial electrochemical reactors, we found that high frequency AC ranging from 1 MHz to 1 kHz (amplitude of 5 V, 30 min) showed only temporary inhibition to the biofilm activity. However, lower frequency (100 Hz, 1.2 or 5 V) treatment led to 47 ± 19% permanent decrease in limiting current on the same biofilm, which is attributed to the action of electrohydrodynamic force that caused biofilm damage and loss of intercellular electron transfer network. Confocal microscopy images show such inactivation mainly occurred at the interface between the biofilm and the electrode. Reducing the frequency further to 1 Hz led to water electrolysis, which generated gas bubbles that flushed all attached cells out of the electrode. These findings provide new references on understanding and regulating biofilm growth, which has broader implications in biofouling control, anaerobic waste treatment, energy and product recovery, and general understanding of microbial ecology and physiology. PMID:27485403

  8. Experimental Study on Current Decay Characteristics of Persistent Current HTS Magnet by Alternating Magnetic Field

    Science.gov (United States)

    Park, Young Gun; Lee, Chang Young; Hwang, Young Jin; Lee, Woo Seung; Lee, Jiho; Jo, Hyun Chul; Chung, Yoon Do; Ko, Tae Kuk

    This paper deals with a current decay characteristics of a high temperature superconducting (HTS) magnet operated in persistent current mode (PCM). In superconducting synchronous machine applications such as linear synchronous motor (LSM), the superconducting coil is designed to operate in the PCM to obtain steady magnetic field with DC transport current. This superconducting magnet operates on a direct current, but it can be exposed to alternating magnetic field due to the armature winding. When the magnet is subjected to an external time-varying magnetic field, it is possible to result in a decay of the current in PCM system due to AC loss. In this research, a PCM system with armature coil which generates time-varying magnetic field was fabricated to verify current decay characteristics by external alternating magnetic field. The current decay rate was measured by using a hall sensor as functions of amplitude and frequency of armature coil.

  9. Changing Configuration of Alternative Energy Systems

    OpenAIRE

    Bhuyan, Radhika; Mytelka, Lynn K.

    2008-01-01

    Recent and rampant regulatory changes for sustainable development are seeking to transform current energy systems towards cleaner and greener forms of energy sources. In this scenario, alternative energy technologies are considered the building blocks towards this transformed energy system. This chapter will show how the alternative energy market since the 1970s changed, in response to external oil price shocks and to other selective pressures and institutions. It will observe that the config...

  10. Alternative Room Cooling System

    Directory of Open Access Journals (Sweden)

    Md. Fazle Rabbi

    2015-06-01

    Full Text Available The rapidly growing population results in an increasing demand for much more residential and commercial buildings, which leads to vertical growth of the buildings and needs proper ventilation of those buildings. Natural air ventilation system is not sufficient for conventional building structures. Hence fans and air-conditioners are must to meet the requirement of proper ventilation as well as space conditioning. Globally building sector consumes largest energy in heating, cooling, ventilation and space conditioning. This load can be minimized by the application of solar chimney and modification in building structure for heating, cooling, ventilation and space conditioning. Passive solar cooling is a subject of interest to provide cooling by using the sun, a powerful energy source. This is done for ensuring human comfort in hot climates. ASHRAE (American Society of Heating, Refrigerating and Air Conditioning Engineers defines Comfort as ‘that state of mind which expresses satisfaction with the thermal environment.’ The present paper describes the development of a solar passive cooling system, which can provide thermal cooling throughout the summer season in hot and humid climates. The constructed passive system works on natural convection mode of air. Such system reduces the inside temperature of up to 5°C from the atmospheric temperature. Temperature can further be reduced by the judicious use of night ventilation.

  11. Alternating current electromagnetic servo induction meter

    Science.gov (United States)

    Bogue, R. K.

    1968-01-01

    Electromagnetic device accurately indicates the responses of various sensors in high performance flight research aircraft to conditions encountered in flight. The device responds to sensor inputs to move a slideable armature along an indicator scale by the force of currents induced in the armature winding.

  12. Real-time control for long ohmic alternate current discharges

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Ivo S., E-mail: ivoc@ipfn.ist.utl.pt; Duarte, Paulo; Fernandes, Horácio; Valcárcel, Daniel F.; Carvalho, Pedro J.; Silva, Carlos; Duarte, André S.; Neto, André; Sousa, Jorge; Batista, António J.N.; Hekkert, Tiago; Carvalho, Bernardo B.; Gomes, Rui B.

    2014-05-15

    Highlights: • 40 Alternate plasma current (AC) semi-cycles without loss of ionization, more than 1 s of operation. • AC discharges automatic control: feedback loops, time-windows control strategy, goal oriented time-windows and exception handling. • Energy deposition and Carbon radiation evolution during the AC discharges. - Abstract: The ISTTOK tokamak has a long tradition on alternate plasma current (AC) discharges, but the old control system was limiting and lacked full system integration. In order to improve the AC discharges performance the ISTTOK fast control system was updated. This control system developed on site based on the Advanced Telecommunications Computing Architecture (ATCA) standard now integrates the information gathered by all the tokamak real-time diagnostics to produce an accurate observation of the plasma parameters. The real-time actuators were also integrated, allowing a Multiple Input Multiple Output (MIMO) control environment with several synchronization strategies available. The control system software was developed in C++ on top of a Linux system with the Multi-threaded Application Real-Time executor (MARTe) Framework to synchronize the real-time code execution under a 100μs control cycle. In addition, to simplify the discharge programming, a visual Human–Machine Interface (HMI) was also developed using the BaseLib2 libraries included in the MARTe Framework. This paper presents the ISTTOK control system and the optimizations that extended the AC current discharges duration to more than 1 s, corresponding to 40 semi-cycles without apparent degradation of the plasma parameters. This upgrade allows ISTTOK to be used as a low-cost material testing facility with long time exposures to nuclear fusion relevant plasmas, comparable (in duration) with medium size tokamaks.

  13. Real-time control for long ohmic alternate current discharges

    International Nuclear Information System (INIS)

    Highlights: • 40 Alternate plasma current (AC) semi-cycles without loss of ionization, more than 1 s of operation. • AC discharges automatic control: feedback loops, time-windows control strategy, goal oriented time-windows and exception handling. • Energy deposition and Carbon radiation evolution during the AC discharges. - Abstract: The ISTTOK tokamak has a long tradition on alternate plasma current (AC) discharges, but the old control system was limiting and lacked full system integration. In order to improve the AC discharges performance the ISTTOK fast control system was updated. This control system developed on site based on the Advanced Telecommunications Computing Architecture (ATCA) standard now integrates the information gathered by all the tokamak real-time diagnostics to produce an accurate observation of the plasma parameters. The real-time actuators were also integrated, allowing a Multiple Input Multiple Output (MIMO) control environment with several synchronization strategies available. The control system software was developed in C++ on top of a Linux system with the Multi-threaded Application Real-Time executor (MARTe) Framework to synchronize the real-time code execution under a 100μs control cycle. In addition, to simplify the discharge programming, a visual Human–Machine Interface (HMI) was also developed using the BaseLib2 libraries included in the MARTe Framework. This paper presents the ISTTOK control system and the optimizations that extended the AC current discharges duration to more than 1 s, corresponding to 40 semi-cycles without apparent degradation of the plasma parameters. This upgrade allows ISTTOK to be used as a low-cost material testing facility with long time exposures to nuclear fusion relevant plasmas, comparable (in duration) with medium size tokamaks

  14. Alternative strategies to prevent and control endoparasite diseases in organic sheep and goat farming systems – a review of current scientific knowledge

    OpenAIRE

    Rahmann, Gerold (Ed.); Seip, Hannah

    2006-01-01

    Infestation with gastro-intestinal nematodes in small ruminants can cause server economic losses and endanger animal welfare. The development of organic farming systems, the increased public awareness for drug residues in agricultural products and the development of resistant strains of parasites have enforced the search for sustainable alternatives. The aim of this paper was to provide information about endoparasite infecting small ruminants, to give an overview of the legal background and t...

  15. Dynamics of laser-guided alternating current high voltage discharges

    Science.gov (United States)

    Daigle, J.-F.; Théberge, F.; Lassonde, P.; Kieffer, J.-C.; Fujii, T.; Fortin, J.; Châteauneuf, M.; Dubois, J.

    2013-10-01

    The dynamics of laser-guided alternating current high voltage discharges are characterized using a streak camera. Laser filaments were used to trigger and guide the discharges produced by a commercial Tesla coil. The streaking images revealed that the dynamics of the guided alternating current high voltage corona are different from that of a direct current source. The measured effective corona velocity and the absence of leader streamers confirmed that it evolves in a pure leader regime.

  16. Alternating current electroluminescent properties of zinc sulfide powders

    OpenAIRE

    Salimian, Alireza

    2012-01-01

    In order to investigate the alternating current electroluminescent properties of zinc sulfide powders the following experiments were conducted: synthesis of zinc sulfide phosphors (comprised of zinc, sulfur and copper dopant); thermal shocking of phosphor materials (sudden cooling, using liquid nitrogen, of phosphor particles heated up to 500oC) and analysis of their alternating current electroluminescent properties as well as studies of particle crystal structures by synchrotron and conventi...

  17. Simulation Study on Alternative Current Fault at Inverter Side of Yunnan-Guangdong Ultrahigh Voltage Direct Current Island Operation System%云广直流孤岛系统逆变侧交流故障仿真研究

    Institute of Scientific and Technical Information of China (English)

    刘洪涛; 张勇; 梅勇; 周煜智; 徐政

    2015-01-01

    云广特高压直流孤岛运行时,送端电网短路比和有效惯性常数显著低于联网方式,承受扰动能力较弱。如果逆变侧交流系统发生接地故障导致逆变站换相失败,直流电压和直流功率将大幅降低,引起送端孤岛系统过电压和频率升高。利用 PSCAD/EMTDC 电磁仿真软件,针对云广直流孤岛系统两种典型运行方式,研究了逆变侧交流系统故障对送端孤岛系统的影响。仿真结果表明:逆变侧交流系统故障引起的直流换相失败持续时间越长,整流侧交流系统短路比和有效惯性常数越小,送端孤岛系统受故障影响越严重;云广直流在两种典型孤岛运行方式下,逆变侧交流系统发生故障时,送端孤岛系统都能保持暂态稳定。%Short circuit ratio and effective inertia constant of the sending end grid under island operation mode of Yunnan-Guangdong ultrahigh voltage direct current(UVDC)project is notably lower than that under networking mode which means weak ability to bear turbulence. If commutation of the inverter station fails caused by grounding fault of alternative current (AC)system at the inverter side ,DC voltage and DC power may substantially reduce and cause overvoltage and frequency of the island system at sending end rise. In allusion two typical running modes of Yunnan-Guangdong UVDC island system, PSCAD/EMTDC electromagnetic simulation software was used for studying affect on the island system at sending end by AC system fault at the inverter side. The simulation results indicate that duration time of DC commutation failure is longer caused by AC system fault at the inverter side,short circuit ratio and effective inertia constant at the rectification side is smaller and affect on island system at sending end by the fault is more serious. In addition,under these two typical island op-eration modes,when the AC system at inverter side develops a fault,island system at sending end

  18. Alternative Structures and Bihamiltonian Systems

    CERN Document Server

    Marmo, G; Simoni, A; Ventriglia, F

    2002-01-01

    In the study of bi-Hamiltonian systems (both classical and quantum) one starts with a given dynamics and looks for all alternative Hamiltonian descriptions it admits.In this paper we start with two compatible Hermitian structures (the quantum analog of two compatible classical Poisson brackets) and look for all the dynamical systems which turn out to be bi-Hamiltonian with respect to them.

  19. Business System Planning Project, Alternatives Analysis

    International Nuclear Information System (INIS)

    The CHG Chief Information Officer (CIO) requested a study of alternatives to the current business system computing environment. This Business Systems Planning (BSP) Project Alternatives Analysis document presents an analysis of the current Project Controls, Work Management, and Business Management systems environment and alternative solutions that support the business functions. The project team has collected requirements and priorities from stakeholders in each business area and documented them in the BSP System Requirements Specification (SRS), RPP-6297. The alternatives analysis process identifies and measures possible solutions in each of the business process areas against the requirements as documented in the SRS. The team gathered input from both internal and external sources to identify and grade the possible solutions. This document captures the results of that activity and recommends a suite of software products. This study was to select the best product based on how well the product met the requirements, not to determine the platform or hardware environment that would be used. Additional analysis documentation can be found in BSP project files

  20. Ground Return Current Behaviour in High Voltage Alternating Current Insulated Cables

    Directory of Open Access Journals (Sweden)

    Roberto Benato

    2014-12-01

    Full Text Available The knowledge of ground return current in fault occurrence plays a key role in the dimensioning of the earthing grid of substations and of cable sealing end compounds, in the computation of rise of earth potential at substation sites and in electromagnetic interference (EMI on neighbouring parallel metallic conductors (pipes, handrails, etc.. Moreover, the ground return current evaluation is also important in steady-state regime since this stray current can be responsible for EMI and also for alternating current (AC corrosion. In fault situations and under some assumptions, the ground return current value at a substation site can be computed by means of k-factors. The paper shows that these simplified and approximated approaches have a lot of limitations and only multiconductor analysis can show the ground return current behaviour along the cable (not only the two end values both in steady-state regime and in short circuit occurrence (e.g., phase-to-ground and phase-to-phase-to-ground. Multiconductor cell analysis (MCA considers the cable system in its real asymmetry without simplified and approximated hypotheses. The sensitivity of ground return current on circuit parameters (cross-bonding box resistances, substation earthing resistances, soil resistivity is presented in the paper.

  1. Alternative electrical transmission systems and their environmental impact

    Energy Technology Data Exchange (ETDEWEB)

    Schiefelbein, G.F.

    1977-08-01

    A general description is provided of electrical transmission systems as an aid in determining their environmental impacts. Alternating current, direct current, overhead systems, underground systems, and water crossings are treated. The cost, performance, reliability, safety, and environmental impact of these systems are compared.

  2. Electrical Characteristics of an Alternating Current Plasma Igniter in Airflow

    Science.gov (United States)

    Zhao, Bingbing; He, Liming; Du, Hongliang; Zhang, Hualei

    2014-04-01

    The electrical characteristics of an alternating current (AC) plasma igniter were investigated for a working gas of air at atmospheric pressure. The discharge voltage and current were measured in air in both breakdown and stable combustion processes, respectively, and the current-zero phenomena, voltage-current (V-I) characteristics were studied for different working gas flow rates. The results indicated that the working gas between anode and cathode could be ionized to generate gas discharge when the voltage reached 8 kV, and the maximum current was 33.36 A. When the current came to zero, current-zero phenomena appeared with duration of 2 μs. At the current-zero moment, dynamic resistance between electrodes became extremely high, and the maximum value could reach 445 kΩ, which was the main factor to restrain the current. With increasing working gas flow rates, the gradient of V-I characteristic curves was increased, as was the dynamic resistance. At a constant driven power, the discharge voltage increased.

  3. Electrical Characteristics of an Alternating Current Plasma Igniter in Airflow

    International Nuclear Information System (INIS)

    The electrical characteristics of an alternating current (AC) plasma igniter were investigated for a working gas of air at atmospheric pressure. The discharge voltage and current were measured in air in both breakdown and stable combustion processes, respectively, and the current-zero phenomena, voltage-current (V-I) characteristics were studied for different working gas flow rates. The results indicated that the working gas between anode and cathode could be ionized to generate gas discharge when the voltage reached 8 kV, and the maximum current was 33.36 A. When the current came to zero, current-zero phenomena appeared with duration of 2 μs. At the current-zero moment, dynamic resistance between electrodes became extremely high, and the maximum value could reach 445 kΩ, which was the main factor to restrain the current. With increasing working gas flow rates, the gradient of V-I characteristic curves was increased, as was the dynamic resistance. At a constant driven power, the discharge voltage increased. (plasma technology)

  4. Transcranial Alternating Current and Random Noise Stimulation: Possible Mechanisms

    Science.gov (United States)

    Antal, Andrea; Herrmann, Christoph S.

    2016-01-01

    Background. Transcranial alternating current stimulation (tACS) is a relatively recent method suited to noninvasively modulate brain oscillations. Technically the method is similar but not identical to transcranial direct current stimulation (tDCS). While decades of research in animals and humans has revealed the main physiological mechanisms of tDCS, less is known about the physiological mechanisms of tACS. Method. Here, we review recent interdisciplinary research that has furthered our understanding of how tACS affects brain oscillations and by what means transcranial random noise stimulation (tRNS) that is a special form of tACS can modulate cortical functions. Results. Animal experiments have demonstrated in what way neurons react to invasively and transcranially applied alternating currents. Such findings are further supported by neural network simulations and knowledge from physics on entraining physical oscillators in the human brain. As a result, fine-grained models of the human skull and brain allow the prediction of the exact pattern of current flow during tDCS and tACS. Finally, recent studies on human physiology and behavior complete the picture of noninvasive modulation of brain oscillations. Conclusion. In future, the methods may be applicable in therapy of neurological and psychiatric disorders that are due to malfunctioning brain oscillations. PMID:27242932

  5. Conventional alternating-current generators and engine generator sets

    Energy Technology Data Exchange (ETDEWEB)

    Segaser, C.L.

    1978-04-01

    Available data and techniques relevant to the selection and analysis of appropriate electrical generating equipment for application in the ICES program are presented. Of the general classes of commercially available a-c generators, the synchronous, rotating field alternator is most suited to ICES applications, and the focus of this technology evaluation. Conventional 60-Hz, alternating-current generators, with standard ratings ranging from 1.25 kVA to 10,000 kVA at voltages from 125 single-phase to 14,400 volts three-phase and speeds up to 1800 rpm are covered. Technical data for representative diesel engine-generator sets for continuous prime power ratings up to 6445 kW are presented. Approximate 1976 costs of standard electrical generating equipment are given for: (1) standard conventional alternating current generators and (2) packaged engine-generator sets. The data indicate a decrease in unit costs as the power ratings increase, with the cost of the slow-speed units somewhat greater than that of the higher speed units. Maintenance data for a typical total energy plant presently in operation indicate that the average cost of maintenance amounts to 41 cents/kWh. A plot of available data also indicates a trend to decreasing operating costs with increasing unit size.

  6. Renal perfusion evaluation by alternating current biosusceptometry of magnetic nanoparticles

    Science.gov (United States)

    Quini, Caio C.; Matos, Juliana F.; Próspero, André G.; Calabresi, Marcos Felipe F.; Zufelato, Nicholas; Bakuzis, Andris F.; Baffa, Oswaldo; Miranda, José Ricardo A.

    2015-04-01

    Alternating current susceptometry, a simple and affordable technique, was employed to study the sensitivity of this approach to assess rat kidney perfusion by the injection of 200 μL of magnetic nanoparticles with a concentration of 23 mg/mL in the femoral vein and the measurement of the signal above the kidney. The instrument was able to detect the signal and the transit time of the first and second pass were measured in five animals with average values of 13.6±4.3 s and 20.6±7.1 s.

  7. Nb-Ti base high-field superconductors with current capacities in excess of 3000 A for application in magnet systems with alternating field components

    International Nuclear Information System (INIS)

    Monolithical and fully transposed conductors with current capacities of up to 1000 A at 5 T and 4.2 K as well as measurement methods are described. For conductor technology, extrusion as well as bundling and sealing methods have been developed and tested, a number of different conductors with different substrate amounts and combinations with high-resistivity substrate have been produced and optimized. Fully transposed conductors have been developed as flat cables. A process for continuous soldering and an equipment for soldering cables have been developed and set up. (orig.)

  8. Thin-film Josephson junctions with alternating critical current density

    Science.gov (United States)

    Moshe, Maayan; Kogan, V. G.; Mints, R. G.

    2009-01-01

    We study the field dependence of the maximum current Im(H) in narrow edge-type thin-film Josephson junctions with alternating critical current density. Im(H) is evaluated within nonlocal Josephson electrodynamics taking into account the stray fields that affect the difference of the order-parameter phases across the junction and therefore the tunneling currents. We find that the phase difference along the junction is proportional to the applied field, depends on the junction geometry, but is independent of the Josephson critical current density gc , i.e., it is universal. An explicit form for this universal function is derived for small currents through junctions of the width W≪Λ , the Pearl length. The result is used to calculate Im(H) . It is shown that the maxima of Im(H)∝1/H and the zeros of Im(H) are equidistant but only in high fields. We find that the spacing between zeros is proportional to 1/W2 . The general approach is applied to calculate Im(H) for a superconducting quantum interference device with two narrow edge-type junctions. If gc changes sign periodically or randomly, as it does in grain boundaries of high- Tc materials and superconductor-ferromagnet-superconductor heterostructures, Im(H) not only acquires the major side peaks, but due to nonlocality the following peaks decay much slower than in bulk junctions.

  9. An Alternating Current Electroosmotic Pump Based on Conical Nanopore Membranes.

    Science.gov (United States)

    Wu, Xiaojian; Ramiah Rajasekaran, Pradeep; Martin, Charles R

    2016-04-26

    Electroosmotic flow (EOF) is used to pump solutions through microfluidic devices and capillary electrophoresis columns. We describe here an EOF pump based on membrane EOF rectification, an electrokinetic phenomenon we recently described. EOF rectification requires membranes with asymmetrically shaped pores, and conical pores in a polymeric membrane were used here. We show here that solution flow through the membrane can be achieved by applying a symmetrical sinusoidal voltage waveform across the membrane. This is possible because the alternating current (AC) carried by ions through the pore is rectified, and we previously showed that rectified currents yield EOF rectification. We have investigated the effect of both the magnitude and frequency of the voltage waveform on flow rate through the membrane, and we have measured the maximum operating pressure. Finally, we show that operating in AC mode offers potential advantages relative to conventional DC-mode EOF pumps. PMID:27046145

  10. Alternative donor transplants for severe aplastic anemia: current experience.

    Science.gov (United States)

    Bacigalupo, Andrea; Sica, Simona

    2016-04-01

    Patients with acquired severe aplastic anemia (SAA), who lack a human leukocyte antigen (HLA) identical sibling donor (SIB), have two therapeutic options: immunosuppressive therapy with anti-thymocyte globulin (ATG) and cyclosporine (CsA), or a transplant from an alternative donor. In these patients, the current guidelines of the European Group for Blood and Marrow Transplantation (EBMT) call for a course of ATG + CsA first and transplantation in case of no response. The alternative donor source can be an unrelated donor (UD), a cord blood (CB) unit, or a family mismatched member, in most instances genetically HLA haplo-mismatched (HAPLO). In the present review, we will discuss recent results of transplants from matched UD and SIB donors, with significantly improved outcome, especially with UD in the past decade. We will also be looking at CB transplants, and the problems of limited stem cell dose. Finally HAPLO grafts have been explored in patients lacking or having rejected an unrelated or CB graft: early results seem encouraging, though the procedure should still be considered experimental. PMID:27000736

  11. Alternatives to animal testing: current status and future perspectives.

    Science.gov (United States)

    Liebsch, Manfred; Grune, Barbara; Seiler, Andrea; Butzke, Daniel; Oelgeschläger, Michael; Pirow, Ralph; Adler, Sarah; Riebeling, Christian; Luch, Andreas

    2011-08-01

    On the occasion of the 20th anniversary of the Center for Alternative Methods to Animal Experiments (ZEBET), an international symposium was held at the German Federal Institute for Risk Assessment (BfR) in Berlin. At the same time, this symposium was meant to celebrate the 50th anniversary of the publication of the book "The Principles of Humane Experimental Technique" by Russell and Burch in 1959 in which the 3Rs principle (that is, Replacement, Reduction, and Refinement) has been coined and introduced to foster the development of alternative methods to animal testing. Another topic addressed by the symposium was the new vision on "Toxicology in the twenty-first Century", as proposed by the US-National Research Council, which aims at using human cells and tissues for toxicity testing in vitro rather than live animals. An overview of the achievements and current tasks, as well as a vision of the future to be addressed by ZEBET@BfR in the years to come is outlined in the present paper. PMID:21607681

  12. Renal perfusion evaluation by alternating current biosusceptometry of magnetic nanoparticles

    International Nuclear Information System (INIS)

    Alternating current susceptometry, a simple and affordable technique, was employed to study the sensitivity of this approach to assess rat kidney perfusion by the injection of 200 μL of magnetic nanoparticles with a concentration of 23 mg/mL in the femoral vein and the measurement of the signal above the kidney. The instrument was able to detect the signal and the transit time of the first and second pass were measured in five animals with average values of 13.6±4.3 s and 20.6±7.1 s. - Highlights: • Rat kidney transit time of magnetic nanoparticles was measured with biosusceptometry. • AC biosusceptometry has sensitivity to measure magnetic nanoparticles in rat kidney. • AC susceptometry has good potential for in vivo studies of magnetic nanoparticles

  13. Alternating-current relaxation of a rotating metallic particle

    Science.gov (United States)

    Guo-Xi, Nie; Wen-Jia, Tian; Ji-Ping, Huang; Guo-Qing, Gu

    2016-06-01

    Based on a first-principles approach, we establish an alternating-current (AC) relaxation theory for a rotating metallic particle with complex dielectric constant . Here is the real part, the conductivity, ω 0 the angular frequency of an AC electric field, and . Our theory yields an accurate interparticle force, which is in good agreement with the existing experiment. The agreement helps to show that the relaxations of two kinds of charges, namely, surface polarized charges (described by ) and free charges (corresponding to ), contribute to the unusually large reduction in the attracting interparticle force. This theory can be adopted to determine the relaxation time of dynamic particles in various fields. Project supported by the National Natural Science Foundation of China (Grant No. 11222544), the Fok Ying Tung Education Foundation (Grant No. 131008), the Program for New Century Excellent Talents in University, China (Grant No. NCET-12-0121), and the National Key Basic Research Program of China (Grant No. 2011CB922004).

  14. Current Pharmaceutical Treatments and Alternative Therapies of Parkinson's Disease.

    Science.gov (United States)

    Dong, Jie; Cui, Yanhua; Li, Song; Le, Weidong

    2016-01-01

    Over the decades, pharmaceutical treatments, particularly dopaminergic (DAergic) drugs have been considered as the main therapy against motor symptoms of Parkinson's disease (PD). It is proposed that DAergic drugs in combination with other medications, such as monoamine oxidase type B inhibitors, catechol-O-methyl transferase inhibitors, anticholinergics and other newly developed non-DAergic drugs can make a better control of motor symptoms or alleviate levodopa-induced motor complications. Moreover, non-motor symptoms of PD, such as cognitive, neuropsychiatric, sleep, autonomic and sensory disturbances caused by intrinsic PD pathology or drug-induced side effects, are gaining increasing attention and urgently need to be taken care of due to their impact on quality of life. Currently, neuroprotective therapies have been investigated extensively in pre-clinical studies, and some of them have been subjected to clinical trials. Furthermore, non-pharmaceutical treatments, including deep brain stimulation (DBS), gene therapy, cell replacement therapy and some complementary managements, such as Tai chi, Yoga, traditional herbs and molecular targeted therapies have also been considered as effective alternative therapies to classical pharmaceutics. This review will provide us updated information regarding the current drugs and non-drugs therapies for PD. PMID:26585523

  15. Development of an alternative plutonium canister assay system (APCA) using He-3 alternative neutron detector

    International Nuclear Information System (INIS)

    In order to deal with the global shortage of He-3 gas, He-3 alternative neutron detectors using ZnS/10B2O3 ceramic scintillators for nuclear security and the safeguards, and a demonstrator of Alternative Plutonium Canister Assay System (APCA) for the safeguards NDA in which the alternative detectors are employed, have been developed with the support of Japanese government (the Ministry of Education, Culture, Sports, Science and Technology). The results of the optical guide property of scintillation lights in the alternative detector tubes derived from the simulations using a ray-tracing code are presented in comparison with the test results of the developed alternative detectors. Furthermore, the fundamental performance of APCA estimated from the neutron Monte-Carlo code MVP and the comparison with the performance of the current PCAS are also described, respectively, together with the future plan of the APCA demonstration test. (author)

  16. HLS bunch current measurement system

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Bunch current is an important parameter for studying the injection fill-pattern in the storage ring and the instability threshold of the bunch, and the bunch current monitor also is an indispensable tool for the top-up injection. A bunch current measurement (BCM) system has been developed to meet the needs of the upgrade project of Hefei Light Source (HLS). This paper presents the layout of the BCM system. The system based on a high-speed digital oscilloscope can be used to measure the bunch current and synchronous phase shift. To obtain the absolute value of bunch-by-bunch current, the calibration coefficient is measured and analyzed. Error analysis shows that the RMS of bunch current is less than 0.01 mA when bunch current is about 5 mA, which can meet project requirement.

  17. A semi-Markov reliability analysis of alternating systems

    International Nuclear Information System (INIS)

    Current nuclear power plants must be highly reliable with respect to safety and economy. Consequently, development of a new safety evaluation methodology is desired for the accurate evaluation of safety and economy. A nuclear power plant consists of many systems. This paper is concerned with the reliability evaluation of alternating systems. An alternating system usually consists of multitrains, and its operation alternates from one train to another. Examples of these are the nuclear service cooling water system, the component cooling water system, and the chemical and volume control system. The alternating systems exhibit strong dynamic time-dependent reliability characteristics because of the alternating operational mode and the technical specification requirements that are particularly difficult to analyze by static fault-tree techniques. The method used in this paper is based on the semi-Markov reliability analysis. The system performance measures evaluated are its contribution to the total risk of the plant (e.g., core damage probability) and to plant unavailability (reactor downtime). It is concluded that the methodology developed in this study can be applied to existing alternating systems for plant-specific evaluation of the various alternatives in technical specifications

  18. Josephson effects in an alternating current biased transition edge sensor

    CERN Document Server

    Gottardi, Luciano; Akamatsu, Hiroki; van der Kuur, Jan; Bruijn, Marcel P; Hartog, Roland H den; Hijmering, Richard; Khosropanah, Pourya; Lambert, Colin; van der Linden, Anton J; Ridder, Marcel L; Suzuki, Toyo; Gao, Jan R

    2016-01-01

    We report the experimental evidence of the ac Josephson effect in a transition edge sensor (TES) operating in a frequency domain multiplexer and biased by ac voltage at MHz frequencies. The effect is observed by measuring the non-linear impedance of the sensor. The TES is treated as a weakly linked superconducting system and within the resistively shunted junction model framework. We provide a full theoretical explanation of the results by finding the analytic solution of the non-inertial Langevian equation of the system and calculating the non-linear response of the detector to a large ac bias current in the presence of noise.

  19. Alternating-current conductivity and dielectric relaxation of bulk iodoargentate

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Hai-Bao, E-mail: duanhaibao4660@163.com; Yu, Shan-Shan; Zhou, Hong

    2015-05-15

    Graphical abstract: The electric modulus shows single dielectric relaxation process in the measured frequency range. - Highlights: • The conduction mechanism is described by quantum mechanical tunneling model. • The applications of dielectric modulus give a simple method for evaluating the activation energy of the dielectric relaxation. • The [Ag{sub 2}I{sub 4}]{sup 2−}1-D chain and [Cu(en){sub 2}]{sup 2+} cation column form the layered stacks by hydrogen bond interactions. - Abstract: An inorganic-organic hybrid compound Cu(en){sub 2}Ag{sub 2}I{sub 4} (en = ethylenediamine) (1) was synthesized and single crystal structurally characterized. Along the [001] direction, the inorganic parts form an infinite 1-D chain and [Cu(en){sub 2}]{sup 2+} cations are separated by inorganic chain. The electrical conductivity and dielectric properties of 1 have been investigated over wide ranges of frequency. The alternating-current conductivities have been fitted to the Almond–West type power law expression with use of a single value of S. It is found that S values for 1 are nearly temperature-independent, which indicates that the conduction mechanism could be quantum mechanical tunneling (QMT) model. The dielectric loss and electric modulus show single dielectric relaxation process. The activation energy obtained from temperature-dependent electric modulus compare with the calculated from the dc conductivity plots.

  20. Inflammatory bowel diseases: an update of current treatment alternatives.

    Directory of Open Access Journals (Sweden)

    Lucrecia Suárez

    2009-11-01

    Full Text Available Inflammatory bowel diseases (IBD are characterized for having an unpredictable clinical course with periods of inactivity alternating with relapses, a very variable response to treatment and the constant threat of diverse complications. Management of IBD in children may be of particular complexity, added to the fact that published clinical trials are limited, and scientific evidence seems contradictory, explain in part why to current date there is no international consensus regarding treatment in this age group. A suitable therapy should aim at inducing and maintaining remission for as long as possible, encourage adequate growth and preventing potential complications from appearing. In more recent years, development of new therapeutic agents has allowed a more integrative approach which takes in consideration other aspects of the disease such as nutritional status, psychological welfare and general quality of life. One must also keep in mind that none of these therapeutic resources is exempt of side effects on short and long term basis, consequently, it is imperative to be thoughtful of individual features in order to make accurate clinical decisions and offer a tailored management plan which should be able to modify the disease evolution.

  1. TO THE MATTER OF APPRAISAL OF TECHNICAL-ECONOMIC INDICES OF STEEL-MELTING FURNACES OF CONSTANT AND ALTERNATING CURRENT

    Directory of Open Access Journals (Sweden)

    Andrej I. Rozhkov

    2010-01-01

    Full Text Available It is shown that using of static thyristor compensation systems improves efficiency, decreases consumption of power and electrodes, but increases the cost of furnaces of alternating current.

  2. Public concerns and alternative nuclear power systems

    International Nuclear Information System (INIS)

    The basic task undertaken in this study was to assess the relative public acceptability of three general types of nuclear power systems as alternatives to the existing Light Water Reactor (LWR) system. Concerns registered toward nuclear power constituted the basic data for this assessment. The primary measure adopted for determining the significance of concerns was the degree of difficulty posed by the concern to the nuclear power decisional structure in the establishment and maintenance of norms to control risks or to advance intended energy objectives. Alleviations or exacerbations of concern resulting from particular attributes of alternative systems were measured from an LWR baseline

  3. Speed Control of a Three Phase Alternating Current Induction Motor Using Space Vector Pulse Width Modulation

    OpenAIRE

    Angelo A. Beltran Jr.

    2014-01-01

    Sinusoidal pulse width modulation is a popular modulation for most alternating current induction motor. It only requires fewer calculations and is easy to implement. However, the shortcomings of using it are low DC voltage utilization, and poor inverter transmission capability. In recent years, there is an increasing trend and more research concentration of using space vector pulse width modulation in adjustable speed drives and renewable energy systems because...

  4. Current Status of Helium-3 Alternative Technologies for Nuclear Safeguards

    Energy Technology Data Exchange (ETDEWEB)

    Henzlova, Daniela [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kouzes, R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); McElroy, R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Peerani, P. [European Commission, Ispra (Italy). Joint Research Centre; Aspinall, M. [Hybrid Instruments Ltd., Birmingham (United Kingdom); Baird, K. [Intl Atomic Energy Agency (IAEA), Vienna (Austria); Bakel, A. [National Nuclear Security Administration (NNSA), Washington, DC (United States); Borella, M. [SCK.CEN, Mol (Belgium); Bourne, M. [Univ. of Michigan, Ann Arbor, MI (United States); Bourva, L. [Canberra Ltd., Oxford (United Kingdom); Cave, F. [Hybrid Instruments Ltd., Birmingham (United Kingdom); Chandra, R. [Arktis Radiation Detectors Ltd., Zurich (Sweden); Chernikova, D. [Chalmers Univ. of Technology (Sweden); Croft, S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dermody, G. [Symetrica Inc., Maynard, MA (United States); Dougan, A. [National Nuclear Security Administration (NNSA), Washington, DC (United States); Ely, J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fanchini, E. [Istituto Nazionale di Fisica Nucleare (INFN), Milano (Italy); Finocchiaro, P. [Istituto Nazionale di Fisica Nucleare (INFN), Milano (Italy); Gavron, Victor [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kureta, M. [Japan Atomic Energy Agency (JAEA), Tokai (Japan); Ianakiev, Kiril Dimitrov [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ishiyama, K. [Japan Atomic Energy Agency (JAEA), Tokai (Japan); Lee, T. [Intl Atomic Energy Agency (IAEA), Vienna (Austria); Martin, Ch. [Symetrica Inc., Maynard, MA (United States); McKinny, K. [GE Reuter-Stokes, Twinsburg, OH (United States); Menlove, Howard Olsen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Orton, Ch. [National Nuclear Security Administration (NNSA), Washington, DC (United States); Pappalardo, A. [Istituto Nazionale di Fisica Nucleare (INFN), Milano (Italy); Pedersen, B. [European Commission, Ispra (Italy). Joint Research Centre; Peranteau, D. [National Nuclear Security Administration (NNSA), Washington, DC (United States); Plenteda, R. [Intl Atomic Energy Agency (IAEA), Vienna (Austria); Pozzi, S. [Univ. of Michigan, Ann Arbor, MI (United States); Schear, M. [Symetrica Inc., Maynard, MA (United States); Seya, M. [Japan Atomic Energy Agency (JAEA), Tokai (Japan); Siciliano, E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Stave, S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sun, L. [Proportional Technologies Inc., Houston, TX (United States); Swinhoe, Martyn Thomas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tagziria, H. [European Commission, Ispra (Italy). Joint Research Centre; Vaccaro, S. [DG Energy (Luxembourg); Takamine, J. [Japan Atomic Energy Agency (JAEA), Tokai (Japan); Weber, A. -L. [Inst. for Radiological Protection and Nuclear Safety (IRSN), Fontenay-aux-Roses (France); Yamaguchi, T. [Japan Atomic Energy Agency (JAEA), Tokai (Japan); Zhu, H. [National Nuclear Security Administration (NNSA), Washington, DC (United States)

    2015-12-01

    International safeguards inspectorates (e.g., International Atomic Energy Agency {IAEA}, or Euratom) rely heavily on neutron assay techniques, and in particular, on coincidence counters for the verification of declared nuclear materials under safeguards and for monitoring purposes. While 3He was readily available, the reliability, safety, ease of use, gamma-ray insensitivity, and high intrinsic thermal neutron detection efficiency of 3He-based detectors obviated the need for alternative detector technologies. However, the recent decline of the 3He gas supply has triggered international efforts to develop and field neutron detectors that make use of alternative materials. In response to this global effort, the U.S. Department of Energy’s (DOE) National Nuclear Security Administration (NNSA) and Euratom launched a joint effort aimed at bringing together international experts, technology users and developers in the field of nuclear safeguards to discuss and evaluate the proposed 3He alternative materials and technologies. The effort involved a series of two workshops focused on detailed overviews and viability assessments of various 3He alternative technologies for use in nuclear safeguards applications. The key objective was to provide a platform for collaborative discussions and technical presentations organized in a compact, workshop-like format to stimulate interactions among the participants. The meetings culminated in a benchmark exercise providing a unique opportunity for the first inter-comparison of several available alternative technologies. This report provides an overview of the alternative technology efforts presented during the two workshops along with a summary of the benchmarking activities and results. The workshop recommendations and key consensus observations are discussed in the report, and used to outline a proposed path forward and future needs foreseeable in the area of 3He-alternative

  5. Current Status of Helium-3 Alternative Technologies for Nuclear Safeguards

    International Nuclear Information System (INIS)

    International safeguards inspectorates (e.g., International Atomic Energy Agency, or Euratom) rely heavily on neutron assay techniques, and in particular, on coincidence counters for the verification of declared nuclear materials under safeguards and for monitoring purposes. While 3He was readily available, the reliability, safety, ease of use, gamma-ray insensitivity, and high intrinsic thermal neutron detection efficiency of 3He-based detectors obviated the need for alternative detector technologies. However, the recent decline of the 3He gas supply has triggered international efforts to develop and field neutron detectors that make use of alternative materials. In response to this global effort, the U.S. Department of Energy's (DOE) National Nuclear Security Administration (NNSA) and Euratom launched a joint effort aimed at bringing together international experts, technology users and developers in the field of nuclear safeguards to discuss and evaluate the proposed 3He alternative materials and technologies. The effort involved a series of two workshops focused on detailed overviews and viability assessments of various 3He alternative technologies for use in nuclear safeguards applications. The key objective was to provide a platform for collaborative discussions and technical presentations organized in a compact, workshop-like format to stimulate interactions among the participants. The meetings culminated in a benchmark exercise providing a unique opportunity for the first inter-comparison of several available alternative technologies. This report provides an overview of the alternative technology efforts presented during the two workshops along with a summary of the benchmarking activities and results. The workshop recommendations and key consensus observations are discussed in the report, and used to outline a proposed path forward and future needs foreseeable in the area of 3He-alternative technologies.

  6. Direct current power delivery system and method

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Di; Garces, Luis Jose; Dai, Jian; Lai, Rixin

    2016-09-06

    A power transmission system includes a first unit for carrying out the steps of receiving high voltage direct current (HVDC) power from an HVDC power line, generating an alternating current (AC) component indicative of a status of the first unit, and adding the AC component to the HVDC power line. Further, the power transmission system includes a second unit for carrying out the steps of generating a direct current (DC) voltage to transfer the HVDC power on the HVDC power line, wherein the HVDC power line is coupled between the first unit and the second unit, detecting a presence or an absence of the added AC component in the HVDC power line, and determining the status of the first unit based on the added AC component.

  7. Alternate current characteristics of SiC powders

    Science.gov (United States)

    Mârtensson, E.; Gäfvert, U.; Önneby, C.

    2001-09-01

    Silicon carbide (SiC) powder is used in nonlinear field grading materials. The composite material, consisting of an insulating polymer matrix filled with the SiC grains, is usually a percolated system with established conducting paths. In order to explain the properties, the electrical characteristic of the SiC powder itself is of interest. The ac characteristics of SiC powders have been studied by dielectric response, capacitance-voltage, and ac-pulse measurements. The frequency, electric field, and pressure dependencies have been analyzed for green and black SiC, which have different doping. The ac characteristics of green and black SiC powders are governed by both the barrier regions at the SiC-grain contacts and the surrounding matrix. The nonlinear loss is determined by the conduction current at the contacts. Depending on the doping level of the SiC grains, the capacitance may be controlled by either the nonlinear capacitance of the barrier region or the linear capacitance of the surrounding matrix. Each contact zone may be modeled by a nonlinear resistance in parallel with both a nonlinear and a linear capacitance. The components are considered to be frequency independent. However, in order to explain the macroscopic frequency and field dependencies of the SiC powders, the use of a network of unique contact zones with dissimilar properties is suggested.

  8. A comparison of alternating current and direct current electrospray ionization for mass spectrometry.

    Science.gov (United States)

    Sarver, Scott A; Chetwani, Nishant; Dovichi, Norman J; Go, David B; Gartner, Carlos A

    2014-04-01

    A series of studies comparing the performance of alternating current electrospray ionization (AC ESI) mass spectrometry (MS) and direct current electrospray ionization (DC ESI) MS have been conducted, exploring the absolute signal intensity and signal-to-background ratios produced by both methods using caffeine and a model peptide as targets. Because the high-voltage AC signal was more susceptible to generating gas discharges, the operating voltage range of AC ESI was significantly smaller than that for DC ESI, such that the absolute signal intensities produced by DC ESI at peak voltages were one to two orders of magnitude greater than those for AC ESI. Using an electronegative nebulizing gas, sulfur hexafluoride (SF6), instead of nitrogen (N2) increased the operating range of AC ESI by ~50%, but did not appreciably improve signal intensities. While DC ESI generated far greater signal intensities, both ionization methods produced comparable signal-to-background noise, with AC ESI spectra appearing qualitatively cleaner. A quantitative calibration analysis was performed for two analytes, caffeine and the peptide MRFA. AC ESI utilizing SF6 outperforms all other techniques for the detection of MRFA, producing chromatographic limits of detection nearly one order of magnitude lower than that of DC ESI utilizing N2, and one-half that of DC ESI utilizing SF6. However, DC ESI outperforms AC ESI for the analysis of caffeine, indicating that improvements in spectral quality may benefit certain compounds or classes of compounds, on an individual basis. PMID:24464359

  9. Experiments with alternate currents of very high frequency

    CERN Document Server

    Tesla, Nikola

    2013-01-01

    Here is one of Nikola Tesla's most important lectures; it brightened the world and everything in it. Of all these phenomena the most important to study' are the current phenomena, on account of the already extensive and evergrowing use of currents for industrial purposes. It is now a century since the first practical source of current was produced, and, ever since, the phenomena which accompany the flow of currents have been diligently studied, and through the untiring efforts of scientific men the simple laws which govern them have been discovered.

  10. Alternatives to animal testing: current status and future perspectives

    OpenAIRE

    Liebsch, Manfred; Grune, Barbara; Seiler, Andrea; Butzke, Daniel; Oelgeschläger, Michael; Pirow, Ralph; Adler, Sarah; Riebeling, Christian; Luch, Andreas

    2011-01-01

    On the occasion of the 20th anniversary of the Center for Alternative Methods to Animal Experiments (ZEBET), an international symposium was held at the German Federal Institute for Risk Assessment (BfR) in Berlin. At the same time, this symposium was meant to celebrate the 50th anniversary of the publication of the book “The Principles of Humane Experimental Technique” by Russell and Burch in 1959 in which the 3Rs principle (that is, Replacement, Reduction, and Refinement) has been coined and...

  11. Fiske steps in Josephson junctions with alternating critical current density

    International Nuclear Information System (INIS)

    We have developed a simple model, in the framework of the Kulik theory of Fiske steps in Josephson junctions, for the electromagnetic resonances observed in the current voltage characteristics of certain high temperature superconductor grain boundary junctions. Some preliminary results are illustrated

  12. Teaching Electrical Energy, Voltage and Current: An Alternative Approach.

    Science.gov (United States)

    Licht, Pieter

    1991-01-01

    A program for teaching the concepts of electric energy, voltage, and current is proposed. The ideas and concepts are introduced in a sequence that places more emphasis on some aspects that are normally treated very briefly. A phenomenological orientation, qualitative and quantitative micro- and macroscopic treatments, and the inclusion of the…

  13. Taxation of Fringe Benefits: Alternative Approaches to Current Problems.

    Science.gov (United States)

    Cohen, Anita E.

    1979-01-01

    The current IRS tax treatment of fringe benefits is seen as inadequate, and the judicial precept confusing, because groups of employee benefits are inappropriately excluded from taxation as perquisites. A tax equalization approach is proposed. Available from Suffolk University Law Review Office, 41 Temple St., Boston, MA 02114. (MSE)

  14. Alternating-Current Motor Drive for Electric Vehicles

    Science.gov (United States)

    Krauthamer, S.; Rippel, W. E.

    1982-01-01

    New electric drive controls speed of a polyphase as motor by varying frequency of inverter output. Closed-loop current-sensing circuit automatically adjusts frequency of voltage-controlled oscillator that controls inverter frequency, to limit starting and accelerating surges. Efficient inverter and ac motor would give electric vehicles extra miles per battery charge.

  15. Alternating current calorimetry at very high pressure and low temperature

    CERN Document Server

    Wilhelm, H

    2002-01-01

    The specific heat of CePd sub 2 sub . sub 0 sub 2 Ge sub 1 sub . sub 9 sub 8 has been measured with an ac calorimetric technique up to 22 GPa for temperatures in the range 0.3 K <=T <=10 K. A thermocouple allowed the temperature oscillations to be read when an ac heating current was sent through the sample. The inverse of the thermovoltage V sub a sub c recorded at low temperature exhibits a pronounced anomaly as a function of pressure. It is shown that 1/V sub a sub c extrapolated to zero temperature is a measure of the Sommerfeld coefficient gamma.

  16. Alternating Pulse Current in Electrocoagulation for Wastewater Treatment to Prevent the Passivation or Al Electrode

    Institute of Scientific and Technical Information of China (English)

    MAO Xuhui; HONG Song; ZHU Hua; LIN Hui; WEI Lin; GAN Fuxing

    2008-01-01

    A novel current feed style, alternating pulse current, was proposed in electrocoagulation aiming at preventing the passivation of electrode materials. The open circuit potential (OCP) measurements after anodic and cathodic potentiodynamic polarization showed that cathodic polarization could activate Al electrode. The surface of Al electrode after alternating pulse current electrocoagulation was investigated by scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS), and the results indicate that passivation of Al is not observed. Furthermore, the simulated wastewater treatment tests show that alternating pulse current electrocoagulation has a visible energy saving effect and is worthy of generalization.

  17. The Flexible Exchange Rate System: Experience and Alternatives

    OpenAIRE

    Dornbusch, Rudiger; Frankel, Jeffrey

    1988-01-01

    We review ten aspects of how floating exchange rates have worked in practice, contrasted with ten characteristics that the system was supposed to have in theory. We conclude that the foreign exchange market is characterized by high transactions-volume, short-term horizons, and an absence of stabilizing speculation. As a result, the exchange rate at times strays from the equilibrium level dictated by fundamentals, contrary to theory. We then look at ten proposed alternatives to the current sys...

  18. Selection of alternative material for common rail direct injection system

    Directory of Open Access Journals (Sweden)

    N. Senguttuvan

    2014-03-01

    Full Text Available Common rail direct fuel injection is a modern variant of direct fuel injection system for petrol and diesel engines. The common rail system prototype was developed in the late 1960s by Robert Huber of Switzerland and the technology further developed by Dr. Marco. In petrol engine MPFI technology was developed and implemented in earlier days. Basically common rail tube was fabricated by steel for petrol engines. In the current study Steel, Brass, Aluminum alloy a356 and ABS materials were analyzed separately and aluminum is found the best material among the steel, brass and ABS material for common rail injection tube. Keywords: Common Rail Injection System, Alternate Material.

  19. SSME engine system integration of the alternate turbopump program

    Science.gov (United States)

    Sander, E. J.; Leahy, J. C.

    1993-01-01

    The effect of the engine level integration of the alternate High Pressure Oxidizer Turbopump (HPOTP) on the performance of the Space Shuttle Main Engine (SSME) is examined with reference to the results of the current engine system ground test data analysis. In particular, attention is given to the observed steady state and transient mainstage engine system effects with respect to various engine hardware combinations. It is concluded that none of the engine system concerns eliminate the turbomump from consideration as a permanent addition to the flight program pending certification.

  20. Laser agitates probability flow in atoms to form alternating current and its peak-dip phenomenon

    CERN Document Server

    Cui, Huai-Yang

    2016-01-01

    By using trajectory-based approaches to quantum transition, it is found that laser can agitate the probability flow in atoms to form alternating current with the frequency of the laser. The detailed physical process of quantum transition is investigated, during which the alternating current in atomic probability flow becomes a key role connecting the external electromagnetic wave with the evolution of the quantum states in atoms. Computer was employed to simulate the physical process. The atomic alternating current may have the peak-dip phenomenon.

  1. 17 CFR 242.301 - Requirements for alternative trading systems.

    Science.gov (United States)

    2010-04-01

    ... trading systems. 242.301 Section 242.301 Commodity and Securities Exchanges SECURITIES AND EXCHANGE... FUTURES Regulation Ats-Alternative Trading Systems § 242.301 Requirements for alternative trading systems. (a) Scope of section. An alternative trading system shall comply with the requirements in...

  2. Alternatives Generation Analysis Long Length Contaminated Equipment Removal System Storage

    International Nuclear Information System (INIS)

    Major pieces of Characterization sampling equipment are currently stored outdoors. This includes the Long Length Contaminated Equipment receiver trailer and transportation trailer. A decision is required to determine the preferred alternative for facilities to store and maintain this equipment. The Long Length Contaminated Equipment Removal System (LLCERS) consists of many tools, mechanisms, and controllers currently stored in various locations. Much of this equipment should be protected from the elements while being stored. Some of the LLCERS equipment should be protected with some kind of roof cover. This decision analysis is to determine the best alternative for weather protection for the large equipment requiring a cover. Additional details are included in Sections 2.0 and 5.0. Key assumptions used in this analysis are detailed in Section 3.2

  3. Regional economic impacts of current and proposed management alternatives for Charles M. Russell National Wildlife Refuge

    Science.gov (United States)

    Koontz, Lynne; Sexton, Natalie; Ishizaki, Asuka; Ritten, John

    2013-01-01

    The National Wildlife Refuge System Improvement Act of 1997 requires all units of the National Wildlife Refuge System to be managed under a Comprehensive Conservation Plan (CCP). The CCP must describe the desired future conditions of a refuge and provide long-range guidance and management direction to achieve refuge purposes. Charles M. Russell (CMR) National Wildlife Refuge, located in north-central Montana, is in the process of developing a range of management goals, objectives, and strategies for the CCP. The CCP for the Refuge must contain an analysis of expected effects associated with current and proposed refuge-management strategies. For refuge CCP planning, an economic analysis provides a means of estimating how current management (No Action Alternative) and proposed management activities (Alternatives) affect the local economy. This type of analysis provides two critical pieces of information: (1) it illustrates a refuge’s contribution to the local community; and (2) it can help in determining whether economic effects are or are not a real concern in choosing among management alternatives. It is important to note that the economic value of a refuge encompasses more than just the impacts on the regional economy. Refuges also provide substantial nonmarket values (values for items not exchanged in established markets) such as maintaining endangered species, preserving wetlands, educating future generations, and adding stability to the ecosystem (Carver and Caudill, 2007). However, quantifying these types of nonmarket values is beyond the scope of this study. This report first presents a description of the local community and economy near the Refuge. Next, the methods used to conduct a regional economic impact analysis are described. An analysis of the final CCP management strategies that could affect stakeholders and residents and the local economy is then presented. The refuge management activities of economic concern in this analysis are:

  4. Regional economic impacts of current and proposed management alternatives for Don Edwards National Wildlife Refuge

    Science.gov (United States)

    Richardson, Leslie; Huber, Chris; Koontz, Lynne

    2012-01-01

    The National Wildlife Refuge System Improvement Act of 1997 requires all units of the National Wildlife Refuge System to be managed under a Comprehensive Conservation Plan. The Comprehensive Conservation Plan must describe the desired future conditions of a Refuge and provide long-range guidance and management direction to achieve refuge purposes. The Don Edwards San Francisco Bay National Wildlife Refuge, located at the south end of California's San Francisco Bay and one of seven refuges in the San Francisco Bay National Wildlife Refuge Complex, is in the process of developing a range of management goals, objectives, and strategies for the Comprehensive Conservation Plan. The Comprehensive Conservation Plan must contain an analysis of expected effects associated with current and proposed Refuge management strategies. For Refuge Comprehensive Conservation Plan planning, a regional economic analysis provides a means of estimating how current management (No Action Alternative) and proposed management activities (alternatives) affect the local economy. This type of analysis provides two critical pieces of information: (1) it illustrates the Don Edwards San Francisco Bay National Wildlife Refuge's contribution to the local community, and (2) it can help in determining whether economic effects are or are not a real concern in choosing among management alternatives. This report first presents a description of the local community and economy near the Don Edwards San Francisco Bay National Wildlife Refuge. Next, the methods used to conduct a regional economic impact analysis are described. An analysis of the final Comprehensive Conservation Plan management strategies that could affect stakeholders, residents, and the local economy is then presented. The management activities of economic concern in this analysis are: * Spending in the local community by Refuge visitors; * Refuge personnel salary spending; and * Refuge purchases of goods and services within the local

  5. Modular Energy Storage System for Alternative Energy Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Janice [Magna Electronics Inc., Auburn Hills, MI (United States); Ervin, Frank [Magna Electronics Inc., Auburn Hills, MI (United States)

    2012-05-15

    An electrical vehicle environment was established to promote research and technology development in the area of high power energy management. The project incorporates a topology that permits parallel development of an alternative energy delivery system and an energy storage system. The objective of the project is to develop technologies, specifically power electronics, energy storage electronics and controls that provide efficient and effective energy management between electrically powered devices in alternative energy vehicles plugin electric vehicles, hybrid vehicles, range extended vehicles, and hydrogen-based fuel cell vehicles. In order to meet the project objectives, the Vehicle Energy Management System (VEMS) was defined and subsystem requirements were obtained. Afterwards, power electronics, energy storage electronics and controls were designed. Finally, these subsystems were built, tested individually, and integrated into an electric vehicle system to evaluate and optimize the subsystems performance. Phase 1 of the program established the fundamental test bed to support development of an electrical environment ideal for fuel cell application and the mitigation of many shortcomings of current fuel cell technology. Phase 2, continued development from Phase 1, focusing on implementing subsystem requirements, design and construction of the energy management subsystem, and the integration of this subsystem into the surrogate electric vehicle. Phase 2 also required the development of an Alternative Energy System (AES) capable of emulating electrical characteristics of fuel cells, battery, gen set, etc. Under the scope of the project, a boost converter that couples the alternate energy delivery system to the energy storage system was developed, constructed and tested. Modeling tools were utilized during the design process to optimize both component and system design. This model driven design process enabled an iterative process to track and evaluate the impact

  6. Alternative Electrochemical Systems for Ozonation of Water

    Science.gov (United States)

    Andrews, Craig C.; Murphy, Oliver J.

    2003-01-01

    Electrochemical systems that are especially well suited for the small-scale generation of ozone and ozonated water for local use have been invented. These systems can operate with very little maintenance, and the only inputs needed during operation are electric power and water. Ozonated water produced by these systems can be used in diverse industrial applications: A few examples include sterilization in the brewing industry, general disinfection, and treatment of sewage and recycled water. The basic principle of operation admits of several alternative system configurations. The heart of the system is a stack of electrolytic cells, each containing a proton-exchange membrane (which serves as a solid electrolyte) sandwiched between a catalytic anode and a catalytic cathode. Preferably, the proton-exchange membrane is made of a perfluorinated sulfonic acid polymer. During electrolysis, a mixture of O2 and O3 gases is generated at the anode and H2 is generated at the cathode. Some of the O3 generated at the anode becomes dissolved in the water. The proportion of O3 in the O2/O3 mixture can be maximized by the selection of suitable electrode materials and the use of a high overpotential. Although the proton-exchange membrane conducts protons, it does not conduct electrons. It is also impermeable by gases; consequently, it maintains separation between the O2/O3 mixture evolved at the anode and the H2 evolved at the cathode.

  7. Cost analysis of Navy acquisition alternatives for the NAVSTAR Global Positioning System

    Science.gov (United States)

    Darcy, T. F.; Smith, G. P.

    1982-12-01

    This research analyzes the life cycle cost (LCC) of the Navy's current and two hypothetical procurement alternatives for NAVSTAR Global Positioning System (GPS) user equipment. Costs are derived by the ARINC Research Corporation ACBEN cost estimating system. Data presentation is in a comparative format describing individual alternative LCC and differential costs between alternatives. Sensitivity analysis explores the impact receiver-processor unit (RPU) first unit production cost has on individual alternative LCC, as well as cost differentials between each alternative. Several benefits are discussed that might provide sufficient cost savings and/or system effectiveness improvements to warrant a procurement strategy other than the existing proposal.

  8. SISTEMAS INMUNES ALTERNATIVOS Alternative Immune Systems

    Directory of Open Access Journals (Sweden)

    LUIS F. CADAVID

    Full Text Available El sistema inmune en animales es una red compleja de moléculas, células y tejidos que de manera conjunta mantienen la integridad fisiológica y genética de los organismos. Convencionalmente se ha considerado la existencia de dos clases de inmunidad, la innata y la adaptativa. La primera es ancestral, con variabilidad limitada y baja discriminación, mientras que la segunda es altamente variable, específica y restringida a vertebra-dos mandibulados. La inmunidad adaptativa se basa en receptores de antígeno que se rearreglan somáticamente para generar una diversidad casi ilimitada de moléculas. Este mecanismo de recombinación somática muy probablemente emergió como consecuencia de un evento de transferencia horizontal de transposones y transposasas bacterianas en el ancestro de los vertebrados mandibulados. El reciente descubrimiento en vertebrados no mandibulados e invertebrados de mecanismos alternativos de inmunidad adaptativa, sugiere que en el transcurso de la evolución distintos grupos animales han encontrado soluciones alternativas al problema del reconocimiento inmunológico.The immune system in animals is a complex network of molecules, cells and tissues that coordinately maintain the physiological and genetic integrity of the organism. Traditionally, two classes of immunity have been considered, the innate immunity and the adaptive immunity. The former is ancestral, with limited variability and low discrimination. The latter is highly variable, specific and limited to jawed vertebrates. Adaptive immunity is based on antigen receptors that rearrange somatically to generate a nearly unlimited diversity of molecules. Likely, this mechanism of somatic recombination arose as a consequence of horizontal transfer of transposons and transposases from bacterial genomes in the ancestor of jawed vertebrates. The recent discovery in jawless vertebrates and invertebrates of alternative adaptive immune mechanisms, suggests that during

  9. Lightning current waveform measuring system

    Science.gov (United States)

    Wojtasinski, R. J.; Fuchs, J. C.; Grove, C. H. (Inventor)

    1978-01-01

    An apparatus is described for monitoring current waveforms produced by lightning strikes which generate currents in an elongated cable. These currents are converted to voltages and to light waves for being transmitted over an optical cable to a remote location. At the remote location, the waves are reconstructed back into electrical waves for being stored into a memory. The information is stored within the memory with a timing signal so that only different signals need be stored in order to reconstruct the wave form.

  10. Current in open quantum systems.

    Science.gov (United States)

    Gebauer, Ralph; Car, Roberto

    2004-10-15

    We show that a dissipative current component is present in the dynamics generated by a Liouville-master equation, in addition to the usual component associated with Hamiltonian evolution. The dissipative component originates from coarse graining in time, implicit in a master equation, and needs to be included to preserve current continuity. We derive an explicit expression for the dissipative current in the context of the Markov approximation. Finally, we illustrate our approach with a simple numerical example, in which a quantum particle is coupled to a harmonic phonon bath and dissipation is described by the Pauli master equation. PMID:15524960

  11. Project on Alternative Systems Study - PASS. Cost comparison of repository systems

    International Nuclear Information System (INIS)

    The development of alternative repository systems and different canister alternatives is being studied by SKB within the frame of the 'Project on Alternative Systems Study, PASS', with the objective of presenting a ranking of systems being currently studied. The rankings is primarily made for three different headings: technology, long-term performance and safety, and costs. The ranking for each of these headings are eventually to be merged into one ranking. The present report presents the basis for the ranking regarding costs. The following four systems have been studied and are presented in order of cost (the less expensive first): Medium Long Holes (MLH), KBS-3 (Modified Plan 92 system), Very Long Holes (VLH), and Very Deep Holes (VDH). A significant outcome of the study was the clear difference in cost between the very expensive system VDH and the other three

  12. Efficacy of lidocaine lontophoresis using either alternating or direct current in hairless rats.

    Science.gov (United States)

    Nakajima, Atsushi; Wakita, Ryo; Haida, Haruka; Fukayama, Haruhisa

    2013-01-01

    The aim of this study was to determine transport of lidocaine ions through a hairless rat skin in vivo and to compare the efficacy of alternating current (AC) with that of direct current (DC) iontophoresis (IOP). We measured the concentration of lidocaine transported through a cellophane membrane or a hairless rat dorsal skin applying either AC-IOP or DC-IOP. The results revealed that lidocaine concentration increased in a time-dependent manner in vitro in both DC-IOP and AC-IOP. However, the in vivo study showed different tendencies in lidocaine concentration. In the DCIOP group, lidocaine concentration reached its maximum 20 min after current application and then decreased rapidly; the AC-IOP group showed an increase in lidocaine concentration in a time-dependent manner. There were no side effects such as electrical burns in the rats. In conclusion, AC can be applied for long periods and DC for short periods, or their application time can be appropriately scheduled. Our study also suggests the mechanism by which voltage waveforms affect the skin when applied by IOP. In the future, these findings will be a solid foundation for developing various kinds of medical equipment such as scheduled drug delivery system that can easily deliver various types of drug. PMID:24146168

  13. Determination of complex formation constants by phase sensitive alternating current polarography: Cadmium-polymethacrylic acid and cadmium-polygalacturonic acid.

    Science.gov (United States)

    Garrigosa, Anna Maria; Gusmão, Rui; Ariño, Cristina; Díaz-Cruz, José Manuel; Esteban, Miquel

    2007-10-15

    The use of phase sensitive alternating current polarography (ACP) for the evaluation of complex formation constants of systems where electrodic adsorption is present has been proposed. The applicability of the technique implies the previous selection of the phase angle where contribution of capacitive current is minimized. This is made using Multivariate Curve Resolution by Alternating Least Squares (MCR-ALS) in the analysis of ACP measurements at different phase angles. The method is checked by the study of the complexation of Cd by polymethacrylic (PMA) and polygalacturonic (PGA) acids, and the optimal phase angles have been ca. -10 degrees for Cd-PMA and ca. -15 degrees for Cd-PGA systems. The goodness of phase sensitive ACP has been demonstrated comparing the determined complex formation constants with those obtained by reverse pulse polarography, a technique that minimizes the electrode adsorption effects on the measured currents. PMID:19073101

  14. 30 CFR 77.900 - Low- and medium-voltage circuits serving portable or mobile three-phase alternating current...

    Science.gov (United States)

    2010-07-01

    ... portable or mobile three-phase alternating current equipment; circuit breakers. 77.900 Section 77.900... mobile three-phase alternating current equipment; circuit breakers. Low- and medium-voltage circuits supplying power to portable or mobile three-phase alternating current equipment shall be protected...

  15. Antibacterial effect of alternating current against Staphylococcus aureus and Pseudomonas aeroginos

    Directory of Open Access Journals (Sweden)

    Mehdi Mirzaii

    2015-05-01

    Full Text Available Background — The use of physical means as an aid for modern medicine in the champion against pathogenic microorganisms holds new approach that recently have begun to be widely recognized. The use of an additional physical means, alternating currents, introduced to inhibit bacterial growth and enhance disinfectant potency. The present study aimed to determine the best frequency of alternating currents in prevention of bacterial growth and to detect the efficacy of alternating currents on disinfectant bactericidal potency. Material and Methods — Electric field strength of 6 and 10 V/cm2 at 50 KHz, 1 MHz, 10 MHz and 20 MHz was applied continuously during lag phases of staphylococcus aureus and pseudomonas aeroginosa. Then Changes in bacterial growth were investigated by the time kill method. Efficacy alternating currents on the current disinfectants bactericidal potency (microzed, deconex, Dettol and glutaraldehyde were evaluated by MIC and MBC. Results — Alternating current at the low voltage and high frequency (10 V/cm2 at 20 MHz reduced the growth of S. aureus and P. aeruginosa effectively. Electric field strength of 10 V/cm2 at 20 MHz showed a better effect on the low level disinfectants such as Dettol and Deconex compared to the high level disinfectants such as Glutaraldehyde, Microzed GP-H and Aniosyme. Conclusion — Detection of a suitable form of alternating current is necessary in the future. This method may be applied as a complementary for eliminating of conductive and semi-conductive surfaces of hospital and increase disinfectant bactericidal potency.

  16. Regional economic analysis of current and proposed management alternatives for Rappahannock River Valley National Wildlife Refuge

    Science.gov (United States)

    Koontz, Lynne; Sexton, Natalie; Donovan, Ryan

    2009-01-01

    The National Wildlife Refuge System Improvement Act of 1997 requires all units of the National Wildlife Refuge System to be managed under a Comprehensive Conservation Plan. The Comprehensive Conservation Plan must describe the desired future conditions of a refuge and provide long-range guidance and management direction to achieve refuge purposes. The Rappahannock River Valley National Wildlife Refuge (refuge) is in the process of developing a range of management goals, objectives, and strategies for the Comprehensive Conservation Plan. The Comprehensive Conservation Plan for the refuge must contain an analysis of expected effects associated with current and proposed refuge management strategies. The purpose of this study was to assess the regional economic implications associated with draft Comprehensive Conservation Plan management strategies. Special interest groups and local residents often criticize a change in refuge management, especially if there is a perceived negative impact to the local economy. Having objective data on economic impacts may show that these fears are overstated. Quite often, the extent of economic benefits a refuge provides to a local community is not fully recognized, yet at the same time the effects of negative changes is overstated. Spending associated with refuge recreational activities, such as wildlife viewing and hunting, can generate considerable tourist activity for surrounding communities. Additionally, refuge personnel typically spend considerable amounts of money purchasing supplies in local stores, repairing equipment and purchasing fuel at the local service stations, and reside and spend their salaries in the local community. For refuge Comprehensive Conservation Plan planning, a regional economic assessment provides a means of estimating how current management (no action alternative) and proposed management activities (alternatives) could affect the local economy. This type of analysis provides two critical pieces of

  17. Method and apparatus for reducing the harmonic currents in alternating-current distribution networks

    Science.gov (United States)

    Beverly, Leon H.; Hance, Richard D.; Kristalinski, Alexandr L.; Visser, Age T.

    1996-01-01

    An improved apparatus and method reduce the harmonic content of AC line and neutral line currents in polyphase AC source distribution networks. The apparatus and method employ a polyphase Zig-Zag transformer connected between the AC source distribution network and a load. The apparatus and method also employs a mechanism for increasing the source neutral impedance of the AC source distribution network. This mechanism can consist of a choke installed in the neutral line between the AC source and the Zig-Zag transformer.

  18. Theoretical modeling of NO electrochemical reduction on multifunctional layer electrode by alternating/direct current electrolysis

    International Nuclear Information System (INIS)

    Highlights: • Mechanistic modeling of nitrogen oxide electrochemical reduction. • Fundamentals of both alternative and direct current electrolysis. • Theoretical optimal frequency in alternative current electrolysis. - Abstract: A one-dimensional symmetric model on NO electrochemical reduction in solid oxide electrolysis cell(SOEC) considering gas transport, electronic conduction, ionic conduction, and electrochemical process based on multifunctional layer electrode is developed. The simulation results agree well with the experimental results both in the direct current(DC) and alternative current(AC) electrolysis. The distributions of the NO concentration in the electrode are predicted in both DC and AC electrolysis. The effects of temperature, voltage, and O2 concentration were investigated on NO alternative current electrolysis and direct current electrolysis processes. The modeling results show that the optimal frequency of 0.3 Hz is corresponded to the maximum NO decomposition rate in different temperatures and voltages. The NO decomposition increases with increasing temperature and decreasing O2 concentration in most cases. At 450 °C, the NO decomposition presents first increased and then decreased trend with different voltages at the frequency of 0.3 Hz. This is similar to the effects of O2 concentration at 450 °C and 475 °C at the same frequency

  19. Defining and resolving current systems in geospace

    Science.gov (United States)

    Ganushkina, N. Y.; Liemohn, M. W.; Dubyagin, S.; Daglis, I. A.; Dandouras, I.; De Zeeuw, D. L.; Ebihara, Y.; Ilie, R.; Katus, R.; Kubyshkina, M.; Milan, S. E.; Ohtani, S.; Ostgaard, N.; Reistad, J. P.; Tenfjord, P.; Toffoletto, F.; Zaharia, S.; Amariutei, O.

    2015-11-01

    Electric currents flowing through near-Earth space (R ≤ 12 RE) can support a highly distorted magnetic field topology, changing particle drift paths and therefore having a nonlinear feedback on the currents themselves. A number of current systems exist in the magnetosphere, most commonly defined as (1) the dayside magnetopause Chapman-Ferraro currents, (2) the Birkeland field-aligned currents with high-latitude "region 1" and lower-latitude "region 2" currents connected to the partial ring current, (3) the magnetotail currents, and (4) the symmetric ring current. In the near-Earth nightside region, however, several of these current systems flow in close proximity to each other. Moreover, the existence of other temporal current systems, such as the substorm current wedge or "banana" current, has been reported. It is very difficult to identify a local measurement as belonging to a specific system. Such identification is important, however, because how the current closes and how these loops change in space and time governs the magnetic topology of the magnetosphere and therefore controls the physical processes of geospace. Furthermore, many methods exist for identifying the regions of near-Earth space carrying each type of current. This study presents a robust collection of these definitions of current systems in geospace, particularly in the near-Earth nightside magnetosphere, as viewed from a variety of observational and computational analysis techniques. The influence of definitional choice on the resulting interpretation of physical processes governing geospace dynamics is presented and discussed.

  20. Current tests of alternative gravity theories: the Modified Newtonian Dynamics case

    OpenAIRE

    Paramos, Jorge; Bertolami, Orfeu

    2006-01-01

    We address the possibility of taking advantage of high accuracy gravitational space experiments in the Solar System and complementary cosmological tests to distinguish between the usual general relativistic theory from the alternative modified Newtonian dynamics paradigm.

  1. Effect of decreasing electrical resistance in Characeae cell membranes caused by the flow of alternating current

    Directory of Open Access Journals (Sweden)

    Edward Śpiewla

    2014-02-01

    Full Text Available By means of the techniques of external electrodes and microelectrodes, it was found that evanescent flow of an alternating current through plasmalemma of Characeae cells neutralises oscillatory change in their electrical resistance and reversibly diminishes its value. This effect is particularly significant in the case of "high resistance cells", but it weakens with increasing temperature. The value of the estimated activation energy indicates that, after flow of the alternating current through the membrane, a rapid increase in the conductivity may be caused by an increase in conductivity of potassium channels. This result seems to support the hypothesis of electroconformational feedback.

  2. Analysis of the dynamic response improvement of a turbocharged diesel engine driven alternating current generating set

    International Nuclear Information System (INIS)

    Reliability of electric supply systems is among the most required necessities of modern society. Turbocharged diesel engine driven alternating current generating sets are often used to prevent electric black outs and/or as prime electric energy suppliers. It is well known that turbocharged diesel engines suffer from an inadequate response to a sudden load increase, this being a consequence of the nature of the energy exchange between the engine and the turbocharger. The dynamic response of turbocharged diesel engines could be improved by electric assisting systems, either by direct energy supply with an integrated starter-generator-booster (ISG) mounted on the engine flywheel, or by an indirect energy supply with an electrically assisted turbocharger. An experimentally verified zero dimensional computer simulation method was used for the analysis of both types of electrical assistance. The paper offers an analysis of the interaction between a turbocharged diesel engine and different electric assisting systems, as well as the requirements for the supporting electric motors that could improve the dynamic response of a diesel engine while driving an AC generating set. When performance class compliance is a concern, it is evident that an integrated starter-generator-booster outperforms an electrically assisted turbocharger for the investigated generating set. However, the electric energy consumption and frequency recovery times are smaller when an electrically assisted turbocharger is applied

  3. Optimal current loop systems for producing uniform magnetic fields

    International Nuclear Information System (INIS)

    This article presents magnetic field uniformity design data for several alternative current loop systems. Universal field symmetry properties of the class of current loop systems that is being considered are elucidated. A common property of the five loop systems that are investigated in detail is that they are all in a sense optimal. This 'Nth order' optimality criterion is defined and discussed. Parameters of selected Nth order current loop systems are quoted. Computations of the field uniformity of these loop systems are presented in graphical form, as 'isogauss' contours, and in tabular form, as the 'normalised volumes' enclosed by the isogauss contours. Information is provided about a current loop system that was actually constructed on the basis of the design data presented here

  4. Alternative drives for motor cars. Hybrid systems, fuel cells, alternative energy sources. 3. ed.; Alternative Antriebe fuer Automobile. Hybridsysteme, Brennstoffzellen, alternative Energietraeger

    Energy Technology Data Exchange (ETDEWEB)

    Stan, Cornel [California Univ., Berkeley, CA (United States); Paris-1 Univ., 75 (France); Pisa Univ. (Italy); Perugia Univ. (Italy); Kronstadt Univ. (Russian Federation)

    2012-07-01

    This book describes and assesses on the basis of the latest research and development projects worldwide what the possibilities are for the realisation of future drive concepts, ranging from battery-driven electromotors to hybrid systems combining electromotor and combustion engine to alternative energy resources such as hydrogen or alcohol. Power density, torque band, acceleration characteristics, specific energy consumption and chemical and noise emissions are the most important criteria for assessing the quality of a drive configuration. The boundary conditions for the introduction of alternative automotive drives are determined by the availability or production characteristics and the storability of the energy resources in question as well as by the degree of technical complexity, costs, safety, infrastructure and service. This book provides an updated overview and analysis of the processes, prime movers and energy resources that can be combined in complex energy management systems for automobiles. Up-to-date information of this kind is indispensable for the development of new concepts. The contents in overview: current data and facts on the development of new concepts; compact overview and analysis of processes, prime movers and energy resources; methods and solutions in designing alternative drives. [German] Die Realisierungsmoeglichkeiten zukuenftiger Antriebskonzepte - von batteriebetriebenen Elektromotoren und Hybridsystemen bestehend aus Elektro- und Verbrennungsmotor ueber Brennstoffzellen bis hin zu alternativen Energietraegern wie Wasserstoff oder Alkohol - werden auf Basis neuesten Forschungs- und Entwicklungsarbeiten weltweit praesentiert und bewertet. Leistungsdichte, Drehmomentverlauf, Beschleunigungscharakteristik, spezifischer Energieverbrauch sowie Emission chemischer Stoffe und Geraeusche sind wichtige Merkmale zur Beurteilung der Qualitaet einer Antriebskonfiguration. Die Verfuegbarkeit oder die Herstellungsmerkmale sowie die Speicherfaehigkeit

  5. On the possible role of stimulation duration for after-effects of transcranial alternating current stimulation

    OpenAIRE

    Stefan Rach; Toralf Neuling; Herrmann, Christoph S.

    2015-01-01

    Transcranial alternating current stimulation is a novel method that allows application of sinusoidal currents to modulate brain oscillations and cognitive processes. Studies in humans have demonstrated tACS after-effects following stimulation durations in the range of minutes. However, such after-effects are absent in animal studies using much shorter stimulation protocols in the range of seconds. Thus, stimulation duration might be a critical parameter for after-effects to occur. To test thi...

  6. Studying Effects of Transcranial Alternating Current Stimulation on Hearing and Auditory Scene Analysis

    NARCIS (Netherlands)

    Riecke, Lars

    2016-01-01

    Recent studies have shown that perceptual detection of near-threshold auditory events may depend on the relative timing of the event and ongoing brain oscillations. Furthermore, transcranial alternating current stimulation (tACS), a non-invasive and silent brain stimulation technique, can entrain co

  7. An investigation of the dynamic behaviors of an MRE isolator subjected to constant and alternating currents

    Science.gov (United States)

    Shi, H. F.; Yu, M.; Zhu, M.; Fu, J.; Choi, S. B.; Xing, Z. W.

    2016-07-01

    This paper presents the dynamic behaviors of a magneto-rheological elastomer (MRE) isolator by applying constant and time-varying exciting currents. As the first step, a shear type of the MRE isolator is devised with a simplified design. Then, the distributions of the magnetic field in the MRE isolator under both constant and alternating exciting currents are analyzed by commercial software (ANSYS). Subsequently, the dynamic performances of the isolator are experimentally evaluated by applying three different inputs: constant, square and sinusoidal exciting current. It has been identified from the experimental results that the constant exciting current can provide optimal performances in static control, while the MRE isolator presents more advantages in dynamic control with the sine wave current excitation. This means that an attenuation coefficient of alternating current should be considered to achieve a better dynamic control effect. On the other hand, it has also been demonstrated that alternating the magnetic field can provide a broader variable range of the viscous damping coefficient than that under constant magnetic field.

  8. Systems impacts of spent fuel disassembly alternatives

    International Nuclear Information System (INIS)

    Three studies were completed to evaluate four alternatives to the disposal of intact spent fuel assemblies in a geologic repository. A preferred spent fuel waste form for disposal was recommended on consideration of (1) package design and fuel/package interaction, (2) long-term, in-repository performance of the waste form, and (3) overall process performance and costs for packaging, handling, and emplacement. The four basic alternative waste forms considered were (1) end fitting removal, (2) fission gas venting, (3) disassembly and close packing, and (4) shearing/immobilization. None of the findings ruled out any alternative on the basis of waste package considerations or long-term performance of the waste form. The third alternative offers flexibility in loading that may prove attractive in the various geologic media under consideration, greatly reduces the number of packages, and has the lowest unit cost. These studies were completed in October, 1981. Since then Westinghouse Electric Corporation and the Office of Nuclear Waste Isolation have completed studies in related fields. This report is now being published to provide publicly the background material that is contained within. 47 references, 28 figures, 31 tables

  9. Alternant Leadership: Increasing School System Effectiveness.

    Science.gov (United States)

    Knoop, Robert; Wagner, James

    1986-01-01

    A model of "alternant leadership"--leading and succeeding one another by turn--is presented that proposes a democratic, collegial, multivoter, team approach to electing educational leaders. The rationale is based on contingency theories of administration and studies on leadership succession. Related articles are EA 519 583 and 584. (MLF)

  10. Systems impacts of spent fuel disassembly alternatives

    Energy Technology Data Exchange (ETDEWEB)

    1984-07-01

    Three studies were completed to evaluate four alternatives to the disposal of intact spent fuel assemblies in a geologic repository. A preferred spent fuel waste form for disposal was recommended on consideration of (1) package design and fuel/package interaction, (2) long-term, in-repository performance of the waste form, and (3) overall process performance and costs for packaging, handling, and emplacement. The four basic alternative waste forms considered were (1) end fitting removal, (2) fission gas venting, (3) disassembly and close packing, and (4) shearing/immobilization. None of the findings ruled out any alternative on the basis of waste package considerations or long-term performance of the waste form. The third alternative offers flexibility in loading that may prove attractive in the various geologic media under consideration, greatly reduces the number of packages, and has the lowest unit cost. These studies were completed in October, 1981. Since then Westinghouse Electric Corporation and the Office of Nuclear Waste Isolation have completed studies in related fields. This report is now being published to provide publicly the background material that is contained within. 47 references, 28 figures, 31 tables.

  11. An Investigation of the Role of Alternate Numeration Systems in Preservice Teacher Mathematics Content Courses

    Science.gov (United States)

    Fasteen, Jodi I.

    Alternate numeration systems are common in preservice teacher (PST) mathematics curricula, but there is limited research on how to leverage alternate systems to promote the development of mathematical knowledge for teaching. I analyzed the role of alternate numeration systems in three ways. I conducted a thematic analysis of current PST textbooks to consider the role of alternate numeration systems in written curricula. I conducted a teaching experiment to analyze PSTs' mathematical activity as they engaged with a base five task sequence to reinvent an algorithm for multiplication. And I introduced problematizing mathematical contexts as a design heuristic, situating this within the design theory of Realistic Mathematics Education. I found that alternate numeration systems can be leveraged to create opportunities for PSTs to (a) engage in guided reinvention of an algorithm, (b) improve understanding of base ten by comparing it to other numeration systems, and (c) reflect on their learning experience and the learning experiences of children.

  12. Nephrogenic systemic fibrosis: Current concepts

    Directory of Open Access Journals (Sweden)

    Prasanta Basak

    2011-01-01

    Full Text Available Nephrogenic systemic fibrosis (NSF was first described in 2000 as a scleromyxedema-like illness in patients on chronic hemodialysis. The relationship between NSF and gadolinium contrast during magnetic resonance imaging was postulated in 2006, and subsequently, virtually all published cases of NSF have had documented prior exposure to gadolinium-containing contrast agents. NSF has been reported in patients from a variety of ethnic backgrounds from America, Europe, Asia and Australia. Skin lesions may evolve into poorly demarcated thickened plaques that range from erythematous to hyperpigmented. With time, the skin becomes markedly indurated and tethered to the underlying fascia. Extracutaneous manifestations also occur. The diagnosis of NSF is based on the presence of characteristic clinical features in the setting of chronic kidney disease, and substantiated by skin histology. Differential diagnosis is with scleroderma, scleredema, scleromyxedema, graft-versus-host disease, etc. NSF has a relentlessly progressive course. While there is no consistently successful treatment for NSF, improving renal function seems to slow or arrest the progression of this condition. Because essentially all cases of NSF have developed following exposure to a gadolinium-containing contrast agent, prevention of this devastating condition involves the careful avoidance of administering these agents to individuals at risk.

  13. Alfalfa Hay Quality and Alternative Pricing Systems

    OpenAIRE

    Hopper, Jared A.; Peterson, Hikaru Hanawa; Burton, Robert O., Jr.

    2004-01-01

    Price-quality relationships for alfalfa hay were analyzed by hedonic pricing models using 1996-2001 Wisconsin auction data. Individual nutrients included in the analysis all affected alfalfa price, with acid detergent fiber accounting for the largest impact. Alternative pricing models, based on an aggregate quality index or detailed quality information, were similar in their ability to predict price. However, disaggregating price predictions to account for differences in relative feed value (...

  14. Direct-current arc and alternating-current spark emission spectrographic field methods for the semiquantitative analysis of geologic materials

    Science.gov (United States)

    Grimes, D.J.; Marranzino, A.P.

    1968-01-01

    Two spectrographic methods are used in mobile field laboratories of the U. S. Geological Survey. In the direct-current arc method, the ground sample is mixed with graphite powder, packed into an electrode crater, and burned to completion. Thirty elements are determined. In the spark method, the sample, ground to pass a 150-mesh screen, is digested in hydrofluoric acid followed by evaporation to dryness and dissolution in aqua regia. The solution is fed into the spark gap by means of a rotating-disk electrode arrangement and is excited with an alternating-current spark discharge. Fourteen elements are determined. In both techniques, light is recorded on Spectrum Analysis No. 1, 35-millimeter film, and the spectra are compared visually with those of standard films.

  15. Current and Future Flight Operating Systems

    Science.gov (United States)

    Cudmore, Alan

    2007-01-01

    This viewgraph presentation reviews the current real time operating system (RTOS) type in use with current flight systems. A new RTOS model is described, i.e. the process model. Included is a review of the challenges of migrating from the classic RTOS to the Process Model type.

  16. Luminescence evolution from alumina ceramic surface before flashover under direct and alternating current voltage in vacuum

    Science.gov (United States)

    Su, Guo-Qiang; Wang, Yi-Bo; Song, Bai-Peng; Mu, Hai-Bao; Zhang, Guan-Jun; Li, Feng; Wang, Meng

    2016-06-01

    The luminescence evolution phenomena from alumina ceramic surface in vacuum under high voltage of direct and alternating current are reported, with the voltage covering a large range from far below to close to the flashover voltage. Its time resolved and spatial distributed behaviors are examined by a photon counting system and an electron-multiplying charge-coupled device (EMCCD) together with a digital camera, respectively. The luminescence before flashover exhibits two stages as voltage increasing, i.e., under a relative low voltage (Stage A), the luminescence is ascribed to radiative recombination of hetero-charges injected into the sample surface layer by Schottky effect; under a higher voltage (Stage B), a stable secondary electron emission process, resulting from the Fowler-Nordheim emission at the cathode triple junction (CTJ), is responsible for the luminescence. Spectrum analysis implies that inner secondary electrons within the surface layer of alumina generated during the SSEE process also participate in the luminescence of Stage B. A comprehensive interpretation of the flashover process is formulated, which might promote a better understanding of flashover issue in vacuum.

  17. Alternative Systemic Treatments for Vitiligo: A Review.

    Science.gov (United States)

    Cohen, Brandon E; Elbuluk, Nada; Mu, Euphemia W; Orlow, Seth J

    2015-12-01

    Vitiligo is a common, acquired disorder of skin pigmentation that can significantly impact quality of life. It often represents a therapeutic challenge, which has resulted in interest in alternative treatments such as herbal and vitamin supplements. In this review, we provide an overview of the most commonly studied complementary agents, describe proposed mechanisms of action, identify potential adverse effects, and discuss the primary evidence supporting their use. Our discussion focuses on L-phenylalanine, Polypodium leucotomos, khellin, Ginkgo biloba, and vitamins and minerals, including vitamins B12, C, and E, folic acid, and zinc used as monotherapy or in combination with other treatments for the management of vitiligo. PMID:26329814

  18. Use of Biosensors as Alternatives to Current Regulatory Methods for Marine Biotoxins

    Directory of Open Access Journals (Sweden)

    Luis M. Botana

    2009-11-01

    Full Text Available Marine toxins are currently monitored by means of a bioassay that requires the use of many mice, which poses a technical and ethical problem in many countries. With the exception of domoic acid, there is a legal requirement for the presence of other toxins (yessotoxin, saxitoxin and analogs, okadaic acid and analogs, pectenotoxins and azaspiracids in seafood to be controlled by bioassay, but other toxins, such as palytoxin, cyclic imines, ciguatera and tetrodotoxin are potentially present in European food and there are no legal requirements or technical approaches available to identify their presence. The need for alternative methods to the bioassay is clearly important, and biosensors have become in recent years a feasible alternative to animal sacrifice. This review will discuss the advantages and disadvantages of using biosensors as alternatives to animal assays for marine toxins, with particular focus on surface plasmon resonance (SPR technology.

  19. Control of marine current energy conversion system

    OpenAIRE

    Nyhlén, Erik

    2010-01-01

    This thesis involves the development of a system for control of a marine current energy conversion system. The control system is developed on the principles of load control, i.e. it aims to control the rotational speed of the turbine by controlling the power extracted from the generator. The system operates by feedback of the generator DC-voltage and current as well as the speed of the water current passing through the turbine. An IGBT-transistor controlled by an AVR-microcontroller executes ...

  20. Effects of alternating and direct current in electrocoagulation process on the removal of cadmium from water

    International Nuclear Information System (INIS)

    Highlights: → Very high removal efficiency of cadmium was achieved by electrocoagulation. → Alternating current (AC) avoids oxide layer and corrosion on anode surface. → Good current transfer between anode and cathode results more removal efficiency. → Compact treatment facility and complete automation. → Aluminum alloy anode prevents residual aluminum in treated water. - Abstract: In practice, direct current (DC) is used in an electrocoagulation processes. In this case, an impermeable oxide layer may form on the cathode as well as corrosion formation on the anode due to oxidation. This prevents the effective current transfer between the anode and cathode, so the efficiency of electrocoagulation processes declines. These disadvantages of DC have been diminished by adopting alternating current (AC) in electrocoagulation processes. The main objective of this study is to investigate the effects of AC and DC on the removal of cadmium from water using aluminum alloy as anode and cathode. The results showed that the removal efficiency of 97.5 and 96.2% with the energy consumption of 0.454 and 1.002 kWh kl-1 was achieved at a current density of 0.2 A/dm2 and pH of 7.0 using aluminum alloy as electrodes using AC and DC, respectively. For both AC and DC, the adsorption of cadmium was preferably fitting Langmuir adsorption isotherm, the adsorption process follows second order kinetics and the temperature studies showed that adsorption was exothermic and spontaneous in nature.

  1. Effects of alternating and direct current in electrocoagulation process on the removal of cadmium from water

    Energy Technology Data Exchange (ETDEWEB)

    Vasudevan, Subramanyan, E-mail: vasudevan65@gmail.com [CSIR-Central Electrochemical Research Institute, Karaikudi 630 006 (India); Lakshmi, Jothinathan; Sozhan, Ganapathy [CSIR-Central Electrochemical Research Institute, Karaikudi 630 006 (India)

    2011-08-15

    Highlights: {yields} Very high removal efficiency of cadmium was achieved by electrocoagulation. {yields} Alternating current (AC) avoids oxide layer and corrosion on anode surface. {yields} Good current transfer between anode and cathode results more removal efficiency. {yields} Compact treatment facility and complete automation. {yields} Aluminum alloy anode prevents residual aluminum in treated water. - Abstract: In practice, direct current (DC) is used in an electrocoagulation processes. In this case, an impermeable oxide layer may form on the cathode as well as corrosion formation on the anode due to oxidation. This prevents the effective current transfer between the anode and cathode, so the efficiency of electrocoagulation processes declines. These disadvantages of DC have been diminished by adopting alternating current (AC) in electrocoagulation processes. The main objective of this study is to investigate the effects of AC and DC on the removal of cadmium from water using aluminum alloy as anode and cathode. The results showed that the removal efficiency of 97.5 and 96.2% with the energy consumption of 0.454 and 1.002 kWh kl{sup -1} was achieved at a current density of 0.2 A/dm{sup 2} and pH of 7.0 using aluminum alloy as electrodes using AC and DC, respectively. For both AC and DC, the adsorption of cadmium was preferably fitting Langmuir adsorption isotherm, the adsorption process follows second order kinetics and the temperature studies showed that adsorption was exothermic and spontaneous in nature.

  2. Operational evaluation of the high flow alternative filter test system

    International Nuclear Information System (INIS)

    An alternative to the current filter test system (Q107) used to test Size 4 (500 cubic feet per min rated flow) and larger nuclear grade high efficiency particulate air (HEPA) filters at DOE Filter Test Facilities (FTFs) has been developed. This new test system, called the High Flow Alternative Filter Test System (HFATS), has undergone a long-term operational evaluation at the Oak Ridge FTF (ORFTF) for: comparison between HEPA filter penetration measurements made with the HFATS and with the Q107; assessment of the HFATS' long-term routine operational performance in the FTF environment; and determination of the potential operational impacts of the HFATS on the FTFs. Data for the operational evaluation were collected by the Oak Ridge staff using both test systems. These data were analyzed and interpreted by Los Alamos staff. A total of 849 filters were tested in the evaluation. The data provided by the HFATS easily permits filter penetration to be reported in terms of: penetration at the size of maximum penetration; number, surface area, or mass penetration; or penetration at 0.3 μm for reference to historical data. Results of the penetration measurement comparisons show that the HFATS measurements at about 0.3 μm aerosol diameter do not differ significantly from the Q107 measurements. Analysis of the HFATS penetration data indicates that for the 100% flow tests maximum penetration most frequently occurs at an aerosol diameter of about 0.15 μm as measured by a laser aerosol spectrometer (LAS). The 0.15 μm HFATS measurements at 100% test flow were markedly higher than the corresponding Q107 measurements. These measurements resulted in over 18% of the filters being rejected by the HFATS only, compared to no filters being rejected only by the Q107 and approximately 0.2% being rejected by both systems

  3. Integrated Alternative Source of Energy System with Grid Substation

    OpenAIRE

    Shyamsundar Gupta; Sankalp Saurabh; A.K. Akella

    2015-01-01

    This paper discusses the modeling, simulation and optimization of integrated alternative source of energy system with grid substation. When there is a lack of energy in grid substation to meet the demand of customer load then alternative source of energy compensates energy deficiency and after that if there is excess energy available then remaining energy is stored in battery bank or sells to grid according to need. In another case when required energy is not generated by alternative sources ...

  4. Unusual Oils from Norway : Alternative petroleum systems?

    OpenAIRE

    2008-01-01

    Some highly atypical oils from Scandinavia have been analysed and compared with some normal oils from the NOCS. The question is whether these atypical oils can represent additional petroleum systems in addition the the well known Mesozoic petroleum system.

  5. Eyes wide shut: Transcranial alternating current stimulation drives alpha rhythm in a state dependent manner

    OpenAIRE

    Philipp Ruhnau; Toralf Neuling; Marco Fuscá; Herrmann, Christoph S.; Gianpaolo Demarchi; Nathan Weisz

    2016-01-01

    Transcranial alternating current stimulation (tACS) is used to modulate brain oscillations to measure changes in cognitive function. It is only since recently that brain activity in human subjects during tACS can be investigated. The present study aims to investigate the phase relationship between the external tACS signal and concurrent brain activity. Subjects were stimulated with tACS at individual alpha frequency during eyes open and eyes closed resting states. Electrodes were placed at Cz...

  6. Corporate Bond Financing of Real Estate Investments - A currently viable alternative to bank loans in Sweden?

    OpenAIRE

    Mårtensson, Viktor; Åström., Ragnar

    2013-01-01

    After the recent financial crisis real estate companies in Sweden experienced difficulties obtaining funding for both new projects as well as refinancing of current investments. The situation in the credit market has since then improved but the refinancing problems that real estate companies experienced during this time has made firms aware of this risk and many companies now seek to diversify their funding sources. This thesis discusses the usage of corporate bonds as an alternative funding ...

  7. Effects of direct and alternating current on the treatment of oily water in an electroflocculation process

    OpenAIRE

    A. A. Cerqueira; P. S. A. Souza; M. R. C. Marques

    2014-01-01

    In the direct current mode (DC), widely used in electroflocculation (EC), the formation of an impermeable oxide layer on the cathode causes the declining of the efficiency of this process. This disadvantage has been reduced by adopting alternating current (AC). In this study, the effects of AC and DC on operational parameters such as the removal of oils and greases (O&G), color and turbidity from oil-in-water (O/W) emulsions of the petroleum industry using aluminum electrodes were investigate...

  8. Sustained diffusive alternating current gliding arc discharge in atmospheric pressure air

    DEFF Research Database (Denmark)

    Zhu, Jiajian; Gao, Jinlong; Li, Zhongshan;

    2014-01-01

    Rapid transition from glow discharge to thermal arc has been a common problem in generating stable high-power non-thermal plasmas especially at ambient conditions. A sustained diffusive gliding arc discharge was generated in a large volume in atmospheric pressure air, driven by an alternating......, synchronized with simultaneously recorded current and voltage waveforms. Dynamic details of the novel non-equilibrium discharge are revealed, which is characterized by a sinusoidal current waveform with amplitude stabilized at around 200 mA intermediate between thermal arc and glow discharge, shedding light to...

  9. Alternative energy systems design and analysis with induction generators

    CERN Document Server

    Sime̳s, M Godoy

    2011-01-01

    New perspectives on using induction generators in alternative energy technologies Durable and cost-effective, induction power generators have undergone numerous improvements that make them an increasingly attractive option for renewable energy applications, particularly for wind and hydropower generation systems. From fundamental concepts to the latest technologies, Alternative Energy Systems: Design and Analysis with Induction Generators, Second Edition provides detailed and accurate coverage of all aspects related to the design, operation, and overall analysis of such systems. Plac

  10. Alternative Algebraic Structures from Bi-Hamiltonian Quantum Systems

    CERN Document Server

    Marmo, G; Simoni, A; Ventriglia, F

    2005-01-01

    We discuss the alternative algebraic structures on the manifold of quantum states arising from alternative Hermitian structures associated with quantum bi-Hamiltonian systems. We also consider the consequences at the level of the Heisenberg picture in terms of deformations of the associative product on the space of observables.

  11. Alternative methods for the design of jet engine control systems

    Science.gov (United States)

    Sain, M. K.; Leake, R. J.; Basso, R.; Gejji, R.; Maloney, A.; Seshadri, V.

    1976-01-01

    Various alternatives to linear quadratic design methods for jet engine control systems are discussed. The main alternatives are classified into two broad categories: nonlinear global mathematical programming methods and linear local multivariable frequency domain methods. Specific studies within these categories include model reduction, the eigenvalue locus method, the inverse Nyquist method, polynomial design, dynamic programming, and conjugate gradient approaches.

  12. Quantum Systems and Alternative Unitary Descriptions

    CERN Document Server

    Marmo, G; Ventriglia, F

    2003-01-01

    Motivated by the existence of bi-Hamiltonian classical systems and the correspondence principle, in this paper we analyze the problem of finding Hermitian scalar products which turn a given flow on a Hilbert space into a unitary one. We show how different invariant Hermitian scalar products give rise to different descriptions of a quantum system in the Ehrenfest and Heisenberg picture.

  13. Alternatives to FORTRAN in control systems

    International Nuclear Information System (INIS)

    Control system software has traditionally been written in assembly language, FORTRAN, or Basic. Today there exist several high-level languages with features that make them convenient and effective in control systems. These features include bit manipulation, user-defined data types, character manipulation, and high-level logical operations. Some of theses languages are quite different from FORTRAN and yet are easy to read and use. We discuss several languages, their features that make them convenient for control systems, and give examples of their use. We focus particular attention on the language C, developed by Bell Laboratories

  14. Alternative energy technologies: integrated energy systems

    International Nuclear Information System (INIS)

    This paper describes the smart energy technology which refers to fully integrated energy systems from generation through distribution and consumption. The main thrust of this approach is to make energy systems more reliable, intelligent and more eco-friendly. Population growth will increase the demand for energy. Climate change is driving the need for carbon dioxide reduction and increase demand for renewable energy sources. Canada's electricity infrastructure deficit is significant and there is a need to replace outdate infrastructure.

  15. Concurrent Electroencephalography Recording During Transcranial Alternating Current Stimulation (tACS).

    Science.gov (United States)

    Fehér, Kristoffer D; Morishima, Yosuke

    2016-01-01

    Oscillatory brain activities are considered to reflect the basis of rhythmic changes in transmission efficacy across brain networks and are assumed to integrate cognitive neural processes. Transcranial alternating current stimulation (tACS) holds the promise to elucidate the causal link between specific frequencies of oscillatory brain activity and cognitive processes. Simultaneous electroencephalography (EEG) recording during tACS would offer an opportunity to directly explore immediate neurophysiological effects of tACS. However, it is not trivial to measure EEG signals during tACS, as tACS creates a huge artifact in EEG data. Here we explain how to set up concurrent tACS-EEG experiments. Two necessary considerations for successful EEG recording while applying tACS are highlighted. First, bridging of the tACS and EEG electrodes via leaking EEG gel immediately saturates the EEG amplifier. To avoid bridging via gel, the viscosity of the EEG gel is the most important parameter. The EEG gel must be viscous to avoid bridging, but at the same time sufficiently fluid to create contact between the tACS electrode and the scalp. Second, due to the large amplitude of the tACS artifact, it is important to consider using an EEG system with a high resolution analog-to-digital (A/D) converter. In particular, the magnitude of the tACS artifact can exceed 100 mV at the vicinity of a stimulation electrode when 1 mA tACS is applied. The resolution of the A/D converter is of importance to measure good quality EEG data from the vicinity of the stimulation site. By following these guidelines for the procedures and technical considerations, successful concurrent EEG recording during tACS will be realized. PMID:26862814

  16. An Alternative Ice Protection System for Turbine Engine Inlets Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal presents a dual approach to the development and certification of an alternative system for ice protection of turbine engine inlets. It combines a new...

  17. Transcranial alternating current stimulation with sawtooth waves: simultaneous stimulation and EEG recording

    Directory of Open Access Journals (Sweden)

    James eDowsett

    2016-03-01

    Full Text Available Transcranial alternating current stimulation (tACS has until now mostly been administered as an alternating sinusoidal wave. Despite modern tACS stimulators being able to deliver alternating current with any arbitrary shape there has been no systematic exploration into the relative benefits of different waveforms. As tACS is a relatively new technique there is a huge parameter space of unexplored possibilities which may prove superior or complimentary to the traditional sinusoidal waveform. Here we begin to address this with an investigation into the effects of sawtooth wave tACS on individual alpha power. Evidence from animal models suggests that the gradient and direction of an electric current should be important factors for the subsequent neural firing rate; we compared positive and negative ramp sawtooth waves to test this. An additional advantage of sawtooth waves is that the resulting artefact in the electroencephalogram (EEG recording is significantly simpler to remove than a sine wave; accordingly we were able to observe alpha oscillations both during and after stimulation.We found that positive ramp sawtooth, but not negative ramp sawtooth, significantly enhanced alpha power during stimulation relative to sham (p<0.01. In addition we tested for an after-effect of both sawtooth and sinusoidal stimulation on alpha power but in this case did not find any significant effect. This preliminary study paves the way for further investigations into the effect of the gradient and direction of the current in tACS which could significantly improve the usefulness of this technique.

  18. Continuous electromagnetic separation of inclusion from aluminum melt using alternating current

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A novel scheme about the continuous electromagnetic purification of aluminum melt was put forward based on the utilization of a square separation pipe and a 50 Hz alternating current to produce electromagnetic force. It is experimentally found that with electrical current of 400 A/cm2, it takes only 10 s to remove 95% inclusion from aluminum melt. Comprehensive numerical simulations were carried out to investigate the dynamics mechanisms behind the process. The results show that the removal of inclusion is attributed to the cooperative effects of electromagnetic buoyancy and the secondary flow induced by the rotational electromagnetic force, and the removal efficient increases with the size of inclusion and the electrical current imposed. Theoretical predictions on the distribution and removal efficiency of inclusion were supported by the experiments.

  19. Alternative food systems and the citizen-consumer

    OpenAIRE

    Lehner, Matthias

    2013-01-01

    Ethically informed and committed consumers are crucial to the functioning of many alternative food systems. These consumers are poorly understood, though, and their common description as informed and democratically minded finds little resemblance to the real world. Few individuals fit the ideal of the concept of the so-called citizen-consumer. This commentary therefore argues that both researchers and practitioners interested in the success of alternative food systems must rethink the concept...

  20. Assessment of a satellite power system and six alternative technologies

    Energy Technology Data Exchange (ETDEWEB)

    Wolsko, T.; Whitfield, R.; Samsa, M.; Habegger, L.S.; Levine, E.; Tanzman, E.

    1981-04-01

    The satellite power system is assessed in comparison to six alternative technologies. The alternatives are: central-station terrestrial photovoltaic systems, conventional coal-fired power plants, coal-gasification/combined-cycle power plants, light water reactor power plants, liquid-metal fast-breeder reactors, and fusion. The comparison is made regarding issues of cost and performance, health and safety, environmental effects, resources, socio-economic factors, and insitutional issues. The criteria for selecting the issues and the alternative technologies are given, and the methodology of the comparison is discussed. Brief descriptions of each of the technologies considered are included. (LEW)

  1. 30 CFR 75.900 - Low- and medium-voltage circuits serving three-phase alternating current equipment; circuit...

    Science.gov (United States)

    2010-07-01

    ... Low- and medium-voltage circuits serving three-phase alternating current equipment; circuit breakers. Low- and medium-voltage power circuits serving three-phase alternating current equipment shall be... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Low- and medium-voltage circuits serving...

  2. Environmental cost-effectiveness of bio diesel production in Greece: Current policies and alternative scenarios

    International Nuclear Information System (INIS)

    Following European Directive 2003/30/EC, the Greek Government adapted legislation that introduces and regulates the bio diesel market. The implemented quota scheme allocates the country's annual, predetermined, tax exempt production of bio diesel to industries based on their ability to meet several criteria. A number of bio diesel supply chain stakeholders have criticized this policy for being efficiency-robbing and vague. This paper uses 2007 data from energy crop farms and three bio diesel-producing companies in order to assess these criticisms. We study the economic and environmental aspects of the currently adopted policy and compare them to three alternative scenarios. We conclude that such criticisms have a merit and that policy makers need to reconsider their alternative options regarding the promotion of bio diesel in transport. Permission of sales directly to local consumers and promotion of forward integration by farmers are efficiency enhancing and environment-friendly means of promoting the use of bio diesel in transport.

  3. Environmental cost-effectiveness of bio diesel production in Greece. Current policies and alternative scenarios

    International Nuclear Information System (INIS)

    Following European Directive 2003/30/EC, the Greek Government adapted legislation that introduces and regulates the bio diesel market. The implemented quota scheme allocates the country's annual, predetermined, tax exempt production of bio diesel to industries based on their ability to meet several criteria. A number of bio diesel supply chain stakeholders have criticized this policy for being efficiency-robbing and vague. This paper uses 2007 data from energy crop farms and three bio diesel-producing companies in order to assess these criticisms. We study the economic and environmental aspects of the currently adopted policy and compare them to three alternative scenarios. We conclude that such criticisms have a merit and that policy makers need to reconsider their alternative options regarding the promotion of bio diesel in transport. Permission of sales directly to local consumers and promotion of forward integration by farmers are efficiency enhancing and environment-friendly means of promoting the use of bio diesel in transport. (author)

  4. Alternative (non-animal) methods for cosmetics testing: current status and future prospects-2010

    DEFF Research Database (Denmark)

    Adler, Sarah; Basketter, David; Creton, Stuart;

    2011-01-01

    The 7th amendment to the EU Cosmetics Directive prohibits to put animal-tested cosmetics on the market in Europe after 2013. In that context, the European Commission invited stakeholder bodies (industry, non-governmental organisations, EU Member States, and the Commission's Scientific Committee on...... methods would not be available in time. The selected experts were asked to analyse the status and prospects of alternative methods and to provide a scientifically sound estimate of the time necessary to achieve full replacement of animal testing. In summary, the experts confirmed that it will take at...... least another 7-9 years for the replacement of the current in vivo animal tests used for the safety assessment of cosmetic ingredients for skin sensitisation. However, the experts were also of the opinion that alternative methods may be able to give hazard information, i.e. to differentiate between...

  5. 自适应反演滑模控制在火箭炮交流伺服系统中的应用%Application of Adaptive Backstepping Sliding Mode Controlin in Alternative Current Servo System of Rocket Gun

    Institute of Scientific and Technical Information of China (English)

    郭亚军; 王晓锋; 马大为; 乐贵高

    2011-01-01

    A adaptive backstepping sliding mode control approach was introduced to control the pitch motion of a rocket gun. Its control law was proposed to guarantee that the control system was ultimately bounded in a Lyapunov sense and make the servo system could track the instruction of reference position globally and asymptotically. In addition, the sliding mode control can restrain effects of parameter uncertainties and external disturbance. The functions of adaptive mechanism and sliding mode control were analyzed by using simulation under different conditions. The simulation results illustrate that the method is applicable and robust.%针对某火箭炮俯仰运动的位置控制问题,采用了一种自适应反演滑模控制方法.自适应反演控制律保证了闭环系统最终有界,使伺服系统能够全局渐进跟踪参考位置指令,从而达到交流伺服系统稳定跟踪控制的目的,滑模控制抑制了模型参数摄动和外界干扰的影响.通过不同条件下的仿真研究,分析了自适应机制和滑模控制在运动控制中的作用,结果表明该方法具有较强的适应性及鲁棒性.

  6. Small Water System Alternatives: Media and Membrane Filtration Alternatives for Small Communities and Households

    Science.gov (United States)

    This webinar presentation will highlight research case studies on innovative drinking water treatment alternatives for small community water systems. Emphasis will be placed on media and membrane filtration technologies capable of meeting the requirements of the Long-Term 2 Enha...

  7. Alternate current interference in pipeline; Interferencia por corrente alternada em dutos

    Energy Technology Data Exchange (ETDEWEB)

    Oliver, Joao Hipolito de Lima [TRANSPETRO - PETROBRAS Transporte S.A., Rio de Janeiro, RJ (Brazil)

    2003-07-01

    This paper regards to the concerning that the pipeline operators should take in to account to better understand and control the alternate current interference (AC- interference). Pipelines sharing rights-of-way with AC high voltage power lines are subjected to AC interference that can cause risk for personnel, operational safety and environment. The AC-interference shall be evaluated, in such way that mitigating action can be applied in order to assure the pipeline is operated in a safety way. The AC-interference evaluation should take in to account the pipeline and the electrical generation/transmission design data. Three approaches are considered: the coating integrity, the personnel chock hazards and the pipeline integrity. The coating integrity is affected by the possibility of high-voltage be induced on the pipeline during power line current fault. The operation and maintenance personnel can be prone to chock hazards (touch voltage and step voltage), depending upon the level of the induced voltage on the pipeline and the ground current. An induced voltage evaluation is then necessary to identify AC potentials in pipeline higher than the safe criteria. The pipeline integrity is concerning to the possibility of occurring alternate current corrosion (AC-corrosion) on the pipe wall. This kind of corrosion is still been investigated, and although it is less critical than the direct current corrosion, it can happen in specific situation. Parameters that affect AC-corrosion are discussed in this paper. Finely it is presented a brief guide to evaluate the possibility of occurring AC- interference in a pipeline and a mitigation measures summary. (author)

  8. Satellite power system salvage and disposal alternatives

    Science.gov (United States)

    1980-11-01

    A wide range of salvage options for the SPS satellite, ranging from use in and beyond geosynchronous orbit to use in low Earth orbit in return and use on Earth are presented. The satellite can be used intact to provide power for various purposes, it can be cannibalized or it can be melted down to supply materials for space or ground based products. The use of SPS beyond its nominal lifetime provides value that can be deducted from the SPS capital investment cost. The present value of the salvage value of the SPS satellites, referenced to the system initial operation data, is on the order of five to ten percent of its on-orbit capital cost. (Given a 30 year satellite lifetime and a four percent discount rate, the theoretical maximum salvage value is 30.8 percent of the capital cost.) The SPS demonstration satellite is available some 30 years earlier than the first full scale SPS satellite and has a salvage value on the order of 80 percent of its on-orbit capital cost. In the event that it becomes desirable to dispose of either the demonstration of full scale SPS satellite, a number of disposal options is presented for which intact disposal costs are less than one percent of capital costs.

  9. Proposed alternatives for a DOE-wide occupational radiation exposure information system

    International Nuclear Information System (INIS)

    The Radiation Exposure Information Reporting System (REIRS) was initiated by the Atomic Energy Commission (AEC) in 1968. While the system has provided a general overview of radiation exposures associated with AEC/ERDA/DOE operations and has satisfied the original intent for a central information system, the need for more detailed information has become evident. The alternatives addressed for a radiation exposure information system were no change in current system, clarification of DOE Order for current system, increased summary information from sites, centralized annual individual dose (exposure) system, and annual dose summary and locator files. A majority of the DOE Ad Hoc Committee has concurred to recommend the annual dose summary and locator files (ADSLF). The acceptance of the ADSLF alternative as the DOE-wide radiation exposure system would give DOE added capability and flexibility in responding to requests for information and would reduce the impact on the sites of special survey requests

  10. Thermally stimulated currents in glassy systems

    CERN Document Server

    Halpern, V

    2003-01-01

    A common interpretation of the results of thermally stimulated current experiments is in terms of a fixed set of states present in the system with a range of activation energies, of which specific subsets are selected and identified by thermal slicing (TS) (or fractional polarization) experiments at different polarization temperatures T sub p. On the other hand, such an interpretation is not consistent with many current theories of supercooled liquids and of the glass transition. The results are presented of our calculations on thermally activated Fredrickson-Andersen model systems, which indicate that the TS technique does identify the isothermal response of the system at T sub p. However, this response need not be associated with specific states present in the system, but can arise for instance from a competition between different relaxation paths for the dipole moments of the individual particles. In addition, the compensation law is found to be obeyed for systems with and without cooperative effects, so t...

  11. Dynamics of single vortex line in the field of external alternative current

    International Nuclear Information System (INIS)

    Motion of a single vortex line in steady state under action of an external force due to alternate transport current, viscosity and pinning forces as well as the Magnus force has been investigated. The presence of the effective vortex mass was also taken into account. The vibrational spectrum of the line had two branches: the low- and high-frequency ones. The latter branch appears due to taking the effective vortex mass into consideration. In present report, the absorption of energy by the vortex, depending on the frequency of external transport current, has been calculated. The frequency dependence of the absorption demonstrates two typical resonance maxima, one of them being due to depinning frequency of the vortex, and the other one due to its cyclotron resonance. The influences of other forces on dynamics of the single vortex line were considered

  12. Air pollution control residues from waste incineration: Current UK situation and assessment of alternative technologies

    International Nuclear Information System (INIS)

    Current disposal options for APC residues in the UK and alternative treatment technologies developed world-wide have been reviewed. APC residues are currently landfilled in the UK where they undergo in situ solidification, although the future acceptability of this option is uncertain because the EU waste acceptance criteria (WAC) introduce strict limits on leaching that are difficult to achieve. Other APC residue treatment processes have been developed which are reported to reduce leaching to below relevant regulatory limits. The Ferrox process, the VKI process, the WES-PHix process, stabilisation/solidification using cementitious binders and a range of thermal treatment processes are reviewed. Thermal treatment technologies convert APC residues combined with other wastes into inert glass or glass-ceramics that encapsulate heavy metals. The waste management industry will inevitably use the cheapest available option for treating APC residues and strict interpretation and enforcement of waste legislation is required if new, potentially more sustainable technologies are to become commercially viable

  13. Preparation of scanning tunneling microscopy tips using pulsed alternating current etching

    International Nuclear Information System (INIS)

    An electrochemical method using pulsed alternating current etching (PACE) to produce atomically sharp scanning tunneling microscopy (STM) tips is presented. An Arduino Uno microcontroller was used to control the number and duration of the alternating current (AC) pulses, allowing for ready optimization of the procedures for both Pt:Ir and W tips using a single apparatus. W tips prepared using constant and pulsed AC power were compared. Tips fashioned using PACE were sharper than those etched with continuous AC power alone. Pt:Ir tips were prepared with an initial coarse etching stage using continuous AC power followed by fine etching using PACE. The number and potential of the finishing AC pulses was varied and scanning electron microscope imaging was used to compare the results. Finally, tip quality using the optimized procedures was verified by UHV-STM imaging. With PACE, at least 70% of the W tips and 80% of the Pt:Ir tips were of sufficiently high quality to obtain atomically resolved images of HOPG or Ni(111)

  14. Preparation of scanning tunneling microscopy tips using pulsed alternating current etching

    Energy Technology Data Exchange (ETDEWEB)

    Valencia, Victor A.; Thaker, Avesh A.; Derouin, Jonathan; Valencia, Damian N.; Farber, Rachael G.; Gebel, Dana A.; Killelea, Daniel R., E-mail: dkillelea@luc.edu [Department of Chemistry and Biochemistry, Loyola University Chicago, 1068 W. Sheridan Rd., Chicago, Illinois 60660 (United States)

    2015-03-15

    An electrochemical method using pulsed alternating current etching (PACE) to produce atomically sharp scanning tunneling microscopy (STM) tips is presented. An Arduino Uno microcontroller was used to control the number and duration of the alternating current (AC) pulses, allowing for ready optimization of the procedures for both Pt:Ir and W tips using a single apparatus. W tips prepared using constant and pulsed AC power were compared. Tips fashioned using PACE were sharper than those etched with continuous AC power alone. Pt:Ir tips were prepared with an initial coarse etching stage using continuous AC power followed by fine etching using PACE. The number and potential of the finishing AC pulses was varied and scanning electron microscope imaging was used to compare the results. Finally, tip quality using the optimized procedures was verified by UHV-STM imaging. With PACE, at least 70% of the W tips and 80% of the Pt:Ir tips were of sufficiently high quality to obtain atomically resolved images of HOPG or Ni(111)

  15. MARAS - a computer code for semi-Markov reliability analysis of alternating systems

    International Nuclear Information System (INIS)

    It is now recognized that current testing and maintenance requirements invoke too many inadvertent reactor trips and that operating staff must devote significant amount of time and effort to comply with the requirements. With this recognition, the value and the impact of the proposed changes in the allowed outage time (AOT) and surveillance test interval(STI) are evaluated for the alternating system. Because of the testing and AOT requirements, the alternating system exhibits semi-Markovian characteristics which change states in accordance with a Markov chain but take a nonexponentially distributed amount of time between changes. It is observed from the results that there is an optimal point that gives lowest core damage probability and that the optimal point depends on input parameters. With these results, we can conclude that the methodology developed in this study can be applied to the existing alternating systems to evaluate accurately the various alternatives in the technical specifications

  16. PERFORMANCE OF ALTERNATIVE COMPONENT PRICING SYSTEMS FOR PORK

    OpenAIRE

    Brorsen, B. Wade; Akridge, Jay T.; Boland, Michael A.; Mauney, Sean; Forrest, John C.

    1998-01-01

    One method of implementing value-based marketing is a component pricing system. This research develops and evaluates alternative component pricing systems for pork. Two electronic technologies for estimating carcass components (optical probe and electromagnetic scanner) were evaluated on two sets of data representing different populations. Model accuracy increased as additional components were added.

  17. Integrated Photovoltaic System Used as an Alternative Power Source

    Directory of Open Access Journals (Sweden)

    Ionel Laurentiu Alboteanu

    2014-09-01

    Full Text Available This paper presents a solution to use solar energy as an alternative source of electricity to conventional sources. The solution is to use a compact photovoltaic system integrated into a micro smart grid. The studied photovoltaic system is used into concrete application for the power supply lighting in a didactic laboratory.

  18. Using Alternative Silvicultural Systems to Integrate Mountain Caribou and Timber Management in British Columbia

    Directory of Open Access Journals (Sweden)

    Harold M. Armleder

    1996-01-01

    Full Text Available Even-aged forest management using the clearcutting silvicultural system as it is currently applied threatens mountain caribou habitat in British Columbia. Since neither complete preservation nor maximum development of timber resources are socially acceptable alternatives, forest managers are anxious to find integrated management options. We describe alternative silvicultural systems currently being tested, including single-tree and group selection. All the treatments have the goal of periodically extracting viable timber volumes while perpetually retaining stand characteristics necessary for caribou. The effects of these logging prescriptions on lichen biomass and growth rates are being tested. Alternative silvicultural systems may become part of a larger strategy to maintain caribou habitat in managed forests.

  19. Heat-flow properties of systems with alternate masses or alternate on-site potentials

    Science.gov (United States)

    Pereira, Emmanuel; Santana, Leonardo M.; Ávila, Ricardo

    2011-07-01

    We address a central issue of phononics: the search of properties or mechanisms to manage the heat flow in reliable materials. We analytically study standard and simple systems modeling the heat flow in solids, namely, the harmonic, self-consistent harmonic and also anharmonic chains of oscillators, and we show an interesting insulating effect: While in the homogeneous models the heat flow decays as the inverse of the particle mass, in the chain with alternate masses it decays as the inverse of the square of the mass difference, that is, it decays essentially as the mass ratio (between the smaller and the larger one) for a large mass difference. A similar effect holds if we alternate on-site potentials instead of particle masses. The existence of such behavior in these different systems, including anharmonic models, indicates that it is a ubiquitous phenomenon with applications in the heat flow control.

  20. CURRENT TRENDS IN PULSATILE DRUG DELIVERY SYSTEMS

    Directory of Open Access Journals (Sweden)

    S. R. Tajane et al.

    2012-01-01

    Full Text Available The purpose for this review on pulsatile drug delivery systems (PDDS is to compile the recent literatures with special focus on the different types and approaches involved in the development of the formulation. Pulsatile drug delivery system is the most interesting time and site-specific system. This system is designed for chronopharmacotherapy. Thus, to mimic the function of living systems and in view of emerging chronotherapeutic approaches, pulsatile delivery, which is meant to release a drug following programmed lag phase, has increasing interest in the recent years. Diseases wherein PDDS are promising include asthma, peptic ulcer, cardiovascular diseases, arthritis, and attention deficit syndrome in children, cancer, diabetes, and hypercholesterolemia. Pulsatile drug delivery system divided into 2 types’ preplanned systems and stimulus induced system, preplanned systems based on osmosis, rupturable layers, and erodible barrier coatings. Stimuli induced system based on electrical, temperature and chemically induced systems. This review also summarizes some current PDDS already available in the market. These systems are useful to several problems encountered during the development of a pharmaceutical dosage form.

  1. Medical Robots: Current Systems and Research Directions

    Directory of Open Access Journals (Sweden)

    Ryan A. Beasley

    2012-01-01

    Full Text Available First used medically in 1985, robots now make an impact in laparoscopy, neurosurgery, orthopedic surgery, emergency response, and various other medical disciplines. This paper provides a review of medical robot history and surveys the capabilities of current medical robot systems, primarily focusing on commercially available systems while covering a few prominent research projects. By examining robotic systems across time and disciplines, trends are discernible that imply future capabilities of medical robots, for example, increased usage of intraoperative images, improved robot arm design, and haptic feedback to guide the surgeon.

  2. Matching bunched beams to alternating gradient focusing systems

    International Nuclear Information System (INIS)

    A numerical procedure for generating phase-space distributions matched to alternating gradient focusing systems has been tested. For a smooth-focusing system a matched distribution can be calculated. With a particle tracing simulation code such a distribution can be followed while adiabatically deforming the focusing forces until an alternating gradient configuration is reached. The distribution remains matched; the final distribution is periodic with the structure period. External nonlinearities, including nonlinear couplings, were included in our examples but space charge was not. This procedure is expected to work with space charge but will require a 3-D space-charge calculation in the simulation code

  3. Project on Alternative Systems Study - PASS. Final report

    International Nuclear Information System (INIS)

    Alternative repository systems for deep disposal of spent fuel and different types of canisters are studied regarding technical aspects in Project on Alternative System Study (PASS). The objective is to present a ranking of repository systems as well as of canister types for each system. The studies and compared systems are: KBS-3, Medium Long Tunnels (MLH), Long tunnels (VLH) and Deep Boreholes (VDH). For KBS-3 and MLH five canister types are compared (copper/steel, copper/lead, copper (HIP), steel/lead and steel), for VLH two types (copper/steel and steel), and for VDH three types (titanium/concrete with non-consolidated fuel assemblies, titanium/concrete with consolidated assemblies and copper (HIP) with non-consolidated assemblies). The comparison is separated into three sub-comparisons (Technology, Long-term performance and safety, and Costs), which eventually are merged into one ranking. With respect to canister alternatives the result is that the copper/steel canister is ranked first for KBS-3, MLH and VLH, while the titanium/concrete canister is ranked first for VDH (non-consolidated as well as consolidated assemblies. With these canister alternatives the merged ranking of repository systems results in placing KBS-3 slightly in front of MLH. VLH comes thereafter and VDH last. (32 refs.)

  4. Plasma current resonance in asymmetric toroidal systems

    Energy Technology Data Exchange (ETDEWEB)

    Hazeltine, R. D. [Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States); Catto, Peter J. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, 167 Albany Street, Cambridge, Massachusetts 02139 (United States)

    2015-09-15

    The well-known singularity in the magnetic differential equation for plasma current in an asymmetric toroidal confinement system is resolved by including in the pressure tensor corrections stemming from finite Larmor radius. The result provides an estimate of the amplitude of spikes in the parallel current that occur on rational magnetic surfaces. Resolution of the singularity is shown to depend on both the ambipolarity condition—the requirement of zero surface-averaged radial current—and the form of the magnetic differential equation near the rational surface.

  5. Advantages of Thesaurus Representation Using the Simple Knowledge Organization System (SKOS) Compared with Proposed Alternatives

    Science.gov (United States)

    Pastor-Sanchez, Juan-Antonio; Martinez Mendez, Francisco Javier; Rodriguez-Munoz, Jose Vicente

    2009-01-01

    Introduction: This paper presents an analysis of the Simple Knowledge Organization System (SKOS) compared with other alternatives for thesaurus representation in the Semantic Web. Method: Based on functional and structural changes of thesauri, provides an overview of the current context in which lexical paradigm is abandoned in favour of the…

  6. European Credit Transfer and Accumulation System: An Alternative Way to Calculate the ECTS Grades

    Science.gov (United States)

    Grosges, Thomas; Barchiesi, Dominique

    2007-01-01

    The European Credit Transfer and Accumulation System (ECTS) has been developed and instituted to facilitate student mobility and academic recognition. This paper presents, discusses, and illustrates the pertinence and the limitation of the current statistical distribution of the ECTS grades, and we propose an alternative way to calculate the ECTS…

  7. OXYGEN BUBBLE DEVELOPMENT ON A PLATINUM ELECTRODE IN BOROSILICATE GLASS MELT BY THE EFFECT OF ALTERNATING CURRENT

    Directory of Open Access Journals (Sweden)

    Jiri Matej

    2014-10-01

    or on alternating reduction and re-forming of oxidic layer on the electrode in the transition range, has been suggested. Start of bubble evolution at low alternating current density has also been observed in simple sodium-calcium-silicate glass melt. A relation between bubble release and platinum corrosion caused by reduced silicon has been suggested

  8. Effects of direct and alternating current on the treatment of oily water in an electroflocculation process

    Directory of Open Access Journals (Sweden)

    A. A. Cerqueira

    2014-09-01

    Full Text Available In the direct current mode (DC, widely used in electroflocculation (EC, the formation of an impermeable oxide layer on the cathode causes the declining of the efficiency of this process. This disadvantage has been reduced by adopting alternating current (AC. In this study, the effects of AC and DC on operational parameters such as the removal of oils and greases (O&G, color and turbidity from oil-in-water (O/W emulsions of the petroleum industry using aluminum electrodes were investigated. Removal efficiencies of 95%, 97% and 99% of O&G, color and turbidity with energy consumption of 0.280 kWh/m³ and electrode consumption of 0.12 g and 0.18 g were achieved at a current density of 3 A, operation time of 3 minutes and initial pH of 9.0 using AC and DC, respectively. In continuous flow tests performed with the same experimental conditions, the electrode consumption at times up to 60 minutes were 1.6 g and 3.4 g using AC and DC, respectively.

  9. Alternative low-level radioactive waste disposal system

    International Nuclear Information System (INIS)

    The alternative disposal system concept suggested by the author is called ARDF, above ground retrievable disposal facility and can be adapted to any humid region. The system consists of a cellular reinforced concrete structure with surface layers of compacted low permeability concrete. The advantages are discussed and the design is detailed. Three volume reduction systems are recommended for collating with the ARDF: supercompactor, pathological and scintillation fluid incinerator, and decontamination

  10. Rapid determination of phenolic compounds in water samples by alternating-current oscillopolarographic titration

    Institute of Scientific and Technical Information of China (English)

    XIAO Jun-ping; WANG Xue-feng; ZHOU Qing-xiang; FAN Xiao-yuan; SU Xian-fa; Bai Hua-hua; DUAN Hai-jing

    2007-01-01

    A rapid, simple and sensitive method was demonstrated for the determination of phenolic compounds in water samples by alternating-current oscillopolarographic titration. With the presence of sulfuric acid, phenol could be transferred into a nitroso-compound by reacting with NaNO2. The titration end-point was obtained by the formation of a sharp cut in the oscillopolarographic with infinitesimal NaNO2 on double platinum electrodes. The results showed that phenol had an excellent linear relationship over the range of 4.82×10-6 -9.65×10-3 mol/L, the RSD of the proposed method was lower than 1.5%, and the spiked recoveries of three real water samples were in the range of 95.6%-106.9%.

  11. Alternating Current Dielectrophoresis Optimization of Pt-Decorated Graphene Oxide Nanostructures for Proficient Hydrogen Gas Sensor.

    Science.gov (United States)

    Wang, Jianwei; Rathi, Servin; Singh, Budhi; Lee, Inyeal; Joh, Han-Ik; Kim, Gil-Ho

    2015-07-01

    Alternating current dielectrophoresis (DEP) is an excellent technique to assemble nanoscale materials. For efficient DEP, the optimization of the key parameters like peak-to-peak voltage, applied frequency, and processing time is required for good device. In this work, we have assembled graphene oxide (GO) nanostructures mixed with platinum (Pt) nanoparticles between the micro gap electrodes for a proficient hydrogen gas sensors. The Pt-decorated GO nanostructures were well located between a pair of prepatterned Ti/Au electrodes by controlling the DEP technique with the optimized parameters and subsequently thermally reduced before sensing. The device fabricated using the DEP technique with the optimized parameters showed relatively high sensitivity (∼10%) to 200 ppm hydrogen gas at room temperature. The results indicates that the device could be used in several industry applications, such as gas storage and leak detection. PMID:26042360

  12. Determination of europium(3) in the presence of Chrome Azurol S by alternating-current polarography

    International Nuclear Information System (INIS)

    The behavior of Eu(3) ions are studied by alternating-current polarography in the presence of a triphenylmethane dye Chrome Azurol S (CAS) in an ammonia buffer solution in a wide range of pH and concentrations. The mechanism of CAS reduction at a dropping mercury electrode is suggested. The studies performed by the saturation curve method and by the method of isomolar series indicate that the ratio of components in the complex formed is 1 : 1. The determination limit for Eu(3) in a 0.1 M NH4Cl solution (pH 7.0) in the presence of CAS is 2.2 x 10-6 M

  13. Digital driver of alternate current motors of the control rods in a nuclear research reactor

    International Nuclear Information System (INIS)

    The updating of the instruments as the operation console of the TRIGA Mark III Salazar Reactor is based on the use of a personal computer that works as data acquisition and control device. The power changes on the reactor have been made through the inserting or extraction of four control rods, that they are operated by mechanisms based in alternate current motors. That is with the object to handling each of the bars and so avoiding too the degradation about the performance of the computer of process. Also it is using four drives of smart kind which do the basic duties for generating the control signals and verifying the sensors state of the limits in continuous form. The computer and drivers are organized as a ring net using the serial port R S-232. The computer of process sends the orders and the identification of destination instrument throughout the net. (Author)

  14. Modeling alternative clad behavior for accident tolerant systems

    International Nuclear Information System (INIS)

    The US Department of Energy Fuel Cycle Research and Development program has a key goal of helping develop accident tolerant fuels (ATF) through investigating fuel and clad forms. In the current work thermochemical modeling and experiment are being used to assess fuel and clad alternatives. Cladding alternatives that have promise to improve fuel performance under accident conditions include the FeCrAl family of alloys and SiC-based composites. These are high strength and radiation resistant alloys and ceramics that have increased resistance to oxidation as compared to zirconium alloys. Accident modeling codes have indicated substantially increased time to failure and resulting effects. In the current work the thermochemical behavior of these materials are being assessed and the work reported here. (author)

  15. Review of Current Nuclear Vacuum System Technologies

    International Nuclear Information System (INIS)

    Nearly all industrial operations generate unwanted dust, particulate matter, and/or liquid wastes. Waste dust and particulates can be readily tracked to other work locations, and airborne particulates can be spread through ventilation systems to all locations within a building, and even vented outside the building - a serious concern for processes involving hazardous, radioactive, or nuclear materials. Several varieties of vacuum systems have been proposed and/or are commercially available for clean up of both solid and liquid hazardous and nuclear materials. A review of current technologies highlights both the advantages and disadvantages of the various systems, and demonstrates the need for a system designed to address issues specific to hazardous and nuclear material cleanup. A review of previous and current hazardous/nuclear material cleanup technologies is presented. From simple conventional vacuums modified for use in industrial operations, to systems specifically engineered for such purposes, the advantages and disadvantages are examined in light of the following criteria: minimal worker exposure; minimal secondary waste generation;reduced equipment maintenance and consumable parts; simplicity of design, yet fully compatible with all waste types; and ease of use. The work effort reviews past, existing and proposed technologies in light of such considerations. Accomplishments of selected systems are presented, including identified areas where technological improvements could be suggested

  16. Rip current monitoring using GPS buoy system

    Science.gov (United States)

    Song, DongSeob; Kim, InHo; Kang, DongSoo

    2014-05-01

    The occurrence of rip current in the Haeundae beach, which is one of the most famous beaches in South Korea, has been threatening beach-goers security in summer season annually. Many coastal scientists have been investigating rip currents by using field observations and measurements, laboratory measurements and wave tank experiments, and computer and numerical modeling. Rip current velocity is intermittent and may rapidly increase within minutes due to larger incoming wave groups or nearshore circulation instabilities. It is important to understand that changes in rip current velocity occur in response to changes in incoming wave height and period as well as changes in water level. GPS buoys have been used to acquire sea level change data, atmospheric parameters and other oceanic variables in sea for the purposes of vertical datum determination, tide correction, radar altimeter calibration, ocean environment and marine pollution monitoring. Therefore, we adopted GPS buoy system for an experiment which is to investigate rip current velocity; it is sporadic and may quickly upsurge within minutes due to larger arriving wave groups or nearshore flow uncertainties. In this study, for high accurate positioning of buy equipment, a Satellite Based Argumentation System DGPS data logger was deployed to investigate within floating object, and it can be acquired three-dimensional coordinate or geodetic position of buoy with continuous NMEA-0183 protocol during 24 hours. The wave height measured by in-situ hydrometer in a cross-shore array clearly increased before and after occurrence of rip current, and wave period also was lengthened around an event. These results show that wave height and period correlate reasonably well with long-shore current interaction in the Haeundae beach. Additionally, current meter data and GPS buoy data showed that rip current velocities, about 0.2 m/s, may become dangerously strong under specific conditions. Acknowledgement This research was

  17. On the possible role of stimulation duration for after-effects of transcranial alternating current stimulation

    Directory of Open Access Journals (Sweden)

    Stefan Rach

    2015-08-01

    Full Text Available Transcranial alternating current stimulation is a novel method that allows application of sinusoidal currents to modulate brain oscillations and cognitive processes. Studies in humans have demonstrated tACS after-effects following stimulation durations in the range of minutes. However, such after-effects are absent in animal studies using much shorter stimulation protocols in the range of seconds. Thus, stimulation duration might be a critical parameter for after-effects to occur. To test this hypothesis, we repeated a recent human tACS experiment with a short duration. We applied alpha tACS intermittently for one second duration while keeping other parameters identical. The results demonstrate that this very short intermittent protocol did not produce after-effects on amplitude or phase of the electroencephalogram. Since synaptic plasticity has been suggested as a possible mechanism for after-effects, our results indicate that a stimulation duration of one second is too short to induce synaptic plasticity. Future studies in animals are required that use extended stimulation durations to reveal the neuronal underpinnings. A better understanding of the mechanisms of tACS after-effects is crucial for potential clinical applications.

  18. Alternating current electrical stimulation enhanced chemotherapy: a novel strategy to bypass multidrug resistance in tumor cells

    International Nuclear Information System (INIS)

    Tumor burden can be pharmacologically controlled by inhibiting cell division and by direct, specific toxicity to the cancerous tissue. Unfortunately, tumors often develop intrinsic pharmacoresistance mediated by specialized drug extrusion mechanisms such as P-glycoprotein. As a consequence, malignant cells may become insensitive to various anti-cancer drugs. Recent studies have shown that low intensity very low frequency electrical stimulation by alternating current (AC) reduces the proliferation of different tumor cell lines by a mechanism affecting potassium channels while at intermediate frequencies interfere with cytoskeletal mechanisms of cell division. The aim of the present study is to test the hypothesis that permeability of several MDR1 over-expressing tumor cell lines to the chemotherapic agent doxorubicin is enhanced by low frequency, low intensity AC stimulation. We grew human and rodent cells (C6, HT-1080, H-1299, SKOV-3 and PC-3) which over-expressed MDR1 in 24-well Petri dishes equipped with an array of stainless steel electrodes connected to a computer via a programmable I/O board. We used a dedicated program to generate and monitor the electrical stimulation protocol. Parallel cultures were exposed for 3 hours to increasing concentrations (1, 2, 4, and 8 μM) of doxorubicin following stimulation to 50 Hz AC (7.5 μA) or MDR1 inhibitor XR9576. Cell viability was assessed by determination of adenylate kinase (AK) release. The relationship between MDR1 expression and the intracellular accumulation of doxorubicin as well as the cellular distribution of MDR1 was investigated by computerized image analysis immunohistochemistry and Western blot techniques. By the use of a variety of tumor cell lines, we show that low frequency, low intensity AC stimulation enhances chemotherapeutic efficacy. This effect was due to an altered expression of intrinsic cellular drug resistance mechanisms. Immunohistochemical, Western blot and fluorescence analysis revealed

  19. Alternating current electrical stimulation enhanced chemotherapy: a novel strategy to bypass multidrug resistance in tumor cells

    Directory of Open Access Journals (Sweden)

    Dini Gabriele

    2006-03-01

    Full Text Available Abstract Background Tumor burden can be pharmacologically controlled by inhibiting cell division and by direct, specific toxicity to the cancerous tissue. Unfortunately, tumors often develop intrinsic pharmacoresistance mediated by specialized drug extrusion mechanisms such as P-glycoprotein. As a consequence, malignant cells may become insensitive to various anti-cancer drugs. Recent studies have shown that low intensity very low frequency electrical stimulation by alternating current (AC reduces the proliferation of different tumor cell lines by a mechanism affecting potassium channels while at intermediate frequencies interfere with cytoskeletal mechanisms of cell division. The aim of the present study is to test the hypothesis that permeability of several MDR1 over-expressing tumor cell lines to the chemotherapic agent doxorubicin is enhanced by low frequency, low intensity AC stimulation. Methods We grew human and rodent cells (C6, HT-1080, H-1299, SKOV-3 and PC-3 which over-expressed MDR1 in 24-well Petri dishes equipped with an array of stainless steel electrodes connected to a computer via a programmable I/O board. We used a dedicated program to generate and monitor the electrical stimulation protocol. Parallel cultures were exposed for 3 hours to increasing concentrations (1, 2, 4, and 8 μM of doxorubicin following stimulation to 50 Hz AC (7.5 μA or MDR1 inhibitor XR9576. Cell viability was assessed by determination of adenylate kinase (AK release. The relationship between MDR1 expression and the intracellular accumulation of doxorubicin as well as the cellular distribution of MDR1 was investigated by computerized image analysis immunohistochemistry and Western blot techniques. Results By the use of a variety of tumor cell lines, we show that low frequency, low intensity AC stimulation enhances chemotherapeutic efficacy. This effect was due to an altered expression of intrinsic cellular drug resistance mechanisms. Immunohistochemical

  20. An alternative technical education system : a case study of Mexico

    OpenAIRE

    Kye Woo Lee

    1998-01-01

    Many developing countries have relied on the varied forms of diversified secondary technical education as the main venue for training skilled workers and mid-level technicians. But there have been numerous and strong critics against this mode of technical education. As an alternative, the Mexican government established the CONALEP system (el Colegio National de Educacion Profesional Tecnica), a new vocational and technical education system) in the late 1970's. This report tests the viability ...

  1. An alternative method to estimate refrigeration system inventory

    International Nuclear Information System (INIS)

    Refrigeration system performance is directly related to the refrigerant mass charge in the equipment. This means that there is an optimum fluid amount that requires less power usage and contributes indirectly to a reduction in greenhouse gas output. Another important factor in fluid charge optimization is that it protects against compressor failure. The best approach for predicting refrigeration system inventory is to find the distribution of refrigerant mass in the evaporator and condenser. This work presents an alternative method for estimation of the refrigeration system inventory based on the first law of thermodynamics and the void fraction correlation of Hughmark. The average error of this alternative method was 5.1% and 7.2% for the first and second experimental validations, respectively, whereas the classical method of Otaki produced an error of 10%. Additionally, a convergence study and a sensitivity test were carried out. This alternative method is especially relevant for unusual heat exchanger geometries, when the external heat transfer coefficient is difficult to obtain from the literature. -- Highlights: ► We create an alternative method to determine the refrigerant charge inventory. ► We carried out experimental validations of this new method. ► We performed a convergence test and sensitivity test to verify the accuracy of the method. ► The results show that the new method generates excellent results. ► The new method has a relevant application in cases of uncommon external geometry

  2. Alternating Current Stimulation for Vision Restoration after Optic Nerve Damage: A Randomized Clinical Trial

    Science.gov (United States)

    Schittkowski, Michael P.; Antal, Andrea; Ambrus, Géza Gergely; Paulus, Walter; Dannhauer, Moritz; Michalik, Romualda; Mante, Alf; Bola, Michal; Lux, Anke; Kropf, Siegfried; Brandt, Stephan A.; Sabel, Bernhard A.

    2016-01-01

    Background Vision loss after optic neuropathy is considered irreversible. Here, repetitive transorbital alternating current stimulation (rtACS) was applied in partially blind patients with the goal of activating their residual vision. Methods We conducted a multicenter, prospective, randomized, double-blind, sham-controlled trial in an ambulatory setting with daily application of rtACS (n = 45) or sham-stimulation (n = 37) for 50 min for a duration of 10 week days. A volunteer sample of patients with optic nerve damage (mean age 59.1 yrs) was recruited. The primary outcome measure for efficacy was super-threshold visual fields with 48 hrs after the last treatment day and at 2-months follow-up. Secondary outcome measures were near-threshold visual fields, reaction time, visual acuity, and resting-state EEGs to assess changes in brain physiology. Results The rtACS-treated group had a mean improvement in visual field of 24.0% which was significantly greater than after sham-stimulation (2.5%). This improvement persisted for at least 2 months in terms of both within- and between-group comparisons. Secondary analyses revealed improvements of near-threshold visual fields in the central 5° and increased thresholds in static perimetry after rtACS and improved reaction times, but visual acuity did not change compared to shams. Visual field improvement induced by rtACS was associated with EEG power-spectra and coherence alterations in visual cortical networks which are interpreted as signs of neuromodulation. Current flow simulation indicates current in the frontal cortex, eye, and optic nerve and in the subcortical but not in the cortical regions. Conclusion rtACS treatment is a safe and effective means to partially restore vision after optic nerve damage probably by modulating brain plasticity. This class 1 evidence suggests that visual fields can be improved in a clinically meaningful way. Trial Registration ClinicalTrials.gov NCT01280877 PMID:27355577

  3. Alternative comparison, analysis, and evaluation of solid waste and materials system alternatives

    International Nuclear Information System (INIS)

    This paper presents a comprehensive analysis of the impact of solid waste technical options on values and objectives that are important to the public. It is written in support of the Solid Waste and Materials Systems Alternatives Study (WHC, 1995). Described are the values that were identified, the major programmatic risks, how the impacts were measured, the performance of alternatives, the methodology used for the analysis, and the implications of the results. Decision analysis was used to guide the collection and analysis of data and the logic of the evaluation. Decision analysis is a structured process for the analysis and evaluation of alternatives. It is theoretically grounded in a set of axioms that capture the basic principles of decision making (von Neuman and Morgenstern 1947). Decision analysis objectively specifies what factors are to be considered, how they are to be measured and evaluated, and heir relative importance. The result is an analysis in which the underlying rationale or logic upon which the decision is based is made explicit. This makes possible open discussion of the decision basis in which facts and values are clearly distinguished, resulting in a well- documented decision that can be clearly explained and justified. The strategy of decision analysis is to analyze the various components relevant to the decision separately and then integrate the individual judgments to arrive at an overall decision. This assures that all the relevant factors are identified and their relative importance is considered. The procedure for obtaining the individual judgments, and the decision rules, for combining them and evaluating alternatives, have both theoretical and empirical foundation in mathematics, economics, and psychology

  4. Resistivity measured by direct and alternating current: why are they different?

    Directory of Open Access Journals (Sweden)

    V. Y. Zadorozhnaya

    2008-11-01

    current. As a result the resistivity measured by direct and alternating current is different. The new algorithm was tested on laboratory measurements data showing its good agreement with theory. The calculation of pore size distribution using IP laboratory data has been presented. The definition of the membrane IP effect is: "Membrane IP is the successive blockage of inter-pore connections due to the excess distribution of ions during current flow".

  5. Convection displacement current and alternative form of Maxwell-Lorentz equations

    CERN Document Server

    Chubykalo, A E; Chubykalo, Andrew E.; Smirnov-Rueda, Roman

    1996-01-01

    Some mathematical inconsistencies in the conventional form of Maxwell's equations extended by Lorentz for a single charge system are discussed. To surmount these in framework of Maxwellian theory, a novel convection displacement current is considered as additional and complementary to the famous Maxwell displacement current. It is shown that this form of the Maxwell-Lorentz equations is similar to that proposed by Hertz for electrodynamics of bodies in motion. Original Maxwell's equations can be considered as a valid approximation for a continuous and closed (or going to infinity) conduction current. It is also proved that our novel form of the Maxwell-Lorentz equations is relativistically invariant. In particular, a relativistically invariant gauge for quasistatic fields has been found to replace the non-invariant Coulomb gauge. The new gauge condition contains the famous relationship between electric and magnetic potentials for one uniformly moving charge that is usually a! ttributed to the Lorentz transfor...

  6. Semi-Markov reliability analysis of alternating systems in a nuclear power plant

    International Nuclear Information System (INIS)

    Nuclear power plant operations that follow current testing and maintenance requirements sometimes result in inadvertent reactor trips, and operating staffs devote a significant amount of time and effort in complying with these requirements. Significant benefits could result from changes in current technical specifications. In this paper the benefits and impacts of changes in allowed outage times (AOTs) and surveillance test intervals (STIs) are evaluated for an alternative system that consists of multiple trains and whose operation is alternated train by train. because of testing and AOT requirements, the alternating system exhibits semi-Markovian characteristics that change states in accordance with a Markov process but take an arbitrarily distributed amount of time between changes. The state probabilities are quantified by memorizing the necessary number of past state probabilities. Two measures of plant performance, namely, core damage probability and plant unavailability (reactor downtime), were calculated for the evaluation of AOT and STI. Results indicate that there is an optimal point that gives the lowest core damage probability and that the methodology developed in this study can be applied to existing alternating systems to evaluate accurately the various alternatives in the technical specifications

  7. Development of motion capture system using alternating magnetic field

    Science.gov (United States)

    Kumagai, Masaaki; Akamatsu, Kazuyoshi

    2005-12-01

    Motion capture systems are widely used for virtual reality, motion acquisition for medical researches, for humanoid robots, for video games, etc. Several types of them have been developed and used for applications considering their advantages and restrictions. Another type of motion capture system that uses alternating magnetic field is proposed in this paper. The system uses a field exciting coil that covers measuring area and a pickup coil attached to target. First, six alternating fields are generated simultaneously in measuring area, and signals are induced on pickup coils according to attitude and position of it. These signals are processed to extract amplitude of exciting components, and state of the pickup coil is calculated from those components. It can detect attitude and displacement of target with high resolution and fast response speed. The principles of detection and brief experimental results are described.

  8. Characterization of interference thin films grown on stainless steel surface by alternate pulse current in a sulphochromic solution

    Directory of Open Access Journals (Sweden)

    Rosa Maria Rabelo Junqueira

    2008-12-01

    Full Text Available The aim of this work was to characterize thin interference films grown on the surface of AISI 304 stainless steel for decorative purposes. Films were grown in a sulphochromic solution at room temperature by an alternating pulse current method. The morphology and chemical state of the elements in the films were investigated by field emission scanning electron microscopy (FESEM, atomic force microscopy (AFM, glow discharge optical emission spectrometry (GDOES, and infrared Fourier transform spectroscopy (FTIR. Depth-sensing indentation (DSI experiments and wear abrasion tests were employed to assess the mechanical resistance of the films. The coloration process resulted in porous thin films which increased the surface roughness of the substrate. The interference films mainly consisted of hydrated chromium oxide containing iron. Increasing film thickness produced different colors and affected the mechanical properties of the coating-substrate system. Thicker films, such as those producing gold and green colors, were softer but more abrasion resistant.

  9. DC bias effect on alternating current electrical conductivity of poly(ethylene terephthalate)/alumina nanocomposites

    Science.gov (United States)

    Nikam, Pravin N.; Deshpande, Vineeta D.

    2016-05-01

    Polymer nanocomposites based on metal oxide (ceramic) nanoparticles are a new class of materials with unique properties and designed for various applications such as electronic device packaging, insulation, fabrication and automotive industries. Poly(ethylene terephthalate) (PET)/alumina (Al2O3) nanocomposites with filler content between 1 wt% and 5 wt% were prepared by melt compounding method using co-rotating twin screw extruder and characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and precision LCR meter techniques. The results revealed that proper uniform dispersion at lower content up to 2 wt% of nano-alumina observed by using TEM. Aggregation of nanoparticles was observed at higher content of alumina examined by using SEM and TEM. The frequency dependences of the alternating current (AC) conductivity (σAC) of PET/alumina nanocomposites on the filler content and DC bias were investigated in the frequency range of 20Hz - 1MHz. The results showed that the AC and direct current (DC) conductivity increases with increasing DC bias and nano-alumina content upto 3 wt%. It follows the Jonscher's universal power law of solids. It revealed that σAC of PET/alumina nanocomposites can be well characterized by the DC conductivity (σDC), critical frequency (ωc), critical exponent of the power law (s). Roll of DC bias potential led to an increase of DC conductivity (σDC) due to the creation of additional conducting paths with the polymer nanocomposites and percolation behavior achieved through co-continuous morphology.

  10. Alternating Current Electrophoretic Deposition of Antibacterial Bioactive Glass-Chitosan Composite Coatings

    Directory of Open Access Journals (Sweden)

    Sigrid Seuss

    2014-07-01

    Full Text Available Alternating current (AC electrophoretic deposition (EPD was used to produce multifunctional composite coatings combining bioactive glass (BG particles and chitosan. BG particles of two different sizes were used, i.e., 2 μm and 20–80 nm in average diameter. The parameter optimization and characterization of the coatings was conducted by visual inspection and by adhesion strength tests. The optimized coatings were investigated in terms of their hydroxyapatite (HA forming ability in simulated body fluid (SBF for up to 21 days. Fourier transform infrared (FTIR spectroscopy results showed the successful HA formation on the coatings after 21 days. The first investigations were conducted on planar stainless steel sheets. In addition, scaffolds made from a TiAl4V6 alloy were considered to show the feasibility of coating of three dimensional structures by EPD. Because both BG and chitosan are antibacterial materials, the antibacterial properties of the as-produced coatings were investigated using E. coli bacteria cells. It was shown that the BG particle size has a strong influence on the antibacterial properties of the coatings.

  11. Bi-frontal transcranial alternating current stimulation in the ripple range reduced overnight forgetting

    Directory of Open Access Journals (Sweden)

    Géza Gergely Ambrus

    2015-09-01

    Full Text Available High frequency oscillations in the hippocampal structures recorded during sleep have been proved to be essential for long-term episodic memory consolidation in both animals and in humans. The aim of this study was to test if transcranial Alternating Current Stimulation (tACS of the dorsolateral prefrontal cortex (DLPFC in the hippocampal ripple range, applied bi-frontally during encoding, could modulate declarative memory performance, measured immediately after encoding, and after a night’s sleep. An associative word-pair learning test, taken from Marshall and colleagues, was used. During an evening encoding phase, participants received 1 mA 140 Hz tACS or sham stimulation over both DLPFCs for 10 minutes while being presented twice with a list of word-pairs. Cued recall performance was investigated 10 minutes after training and the morning following the training session. Forgetting from evening to morning was observed in the sham condition, but not in the 140 Hz stimulation condition. 140 Hz tACS during encoding may have an effect on the consolidation of declarative material.

  12. From amusic to musical?--Improving pitch memory in congenital amusia with transcranial alternating current stimulation.

    Science.gov (United States)

    Schaal, Nora K; Pfeifer, Jasmin; Krause, Vanessa; Pollok, Bettina

    2015-11-01

    Brain imaging studies highlighted structural differences in congenital amusia, a life-long perceptual disorder that is associated with pitch perception and pitch memory deficits. A functional anomaly characterized by decreased low gamma oscillations (30-40 Hz range) in the right dorsolateral prefrontal cortex (DLPFC) during pitch memory has been revealed recently. Thus, the present study investigates whether applying transcranial alternating current stimulation (tACS) at 35 Hz to the right DLPFC would improve pitch memory. Nine amusics took part in two tACS sessions (either 35 Hz or 90 Hz) and completed a pitch and visual memory task before and during stimulation. 35 Hz stimulation facilitated pitch memory significantly. No modulation effects were found with 90 Hz stimulation or on the visual task. While amusics showed a selective impairment of pitch memory before stimulation, the performance during 35 Hz stimulation was not significantly different to healthy controls anymore. Taken together, the study shows that modulating the right DLPFC with 35 Hz tACS in congenital amusia selectively improves pitch memory performance supporting the hypothesis that decreased gamma oscillations within the DLPFC are causally involved in disturbed pitch memory and highlight the potential use of tACS to interact with cognitive processes. PMID:26254878

  13. 40Hz-Transcranial alternating current stimulation (tACS) selectively modulates speech perception.

    Science.gov (United States)

    Rufener, Katharina S; Zaehle, Tino; Oechslin, Mathias S; Meyer, Martin

    2016-03-01

    The present study investigated the functional relevance of gamma oscillations for the processing of rapidly changing acoustic features in speech signals. For this purpose we analyzed repetition-induced perceptual learning effects in 18 healthy adult participants. The participants received either 6Hz or 40Hz tACS over the bilateral auditory cortex, while repeatedly performing a phoneme categorization task. In result, we found that 40Hz tACS led to a specific alteration in repetition-induced perceptual learning. While participants in the non-stimulated control group as well as those in the experimental group receiving 6Hz tACS considerably improved their perceptual performance, the application of 40Hz tACS selectively attenuated the repetition-induced improvement in phoneme categorization abilities. Our data provide causal evidence for a functional relevance of gamma oscillations during the perceptual learning of acoustic speech features. Moreover, we demonstrate that even less than twenty minutes of alternating current stimulation below the individual perceptual threshold is sufficient to affect speech perception. This finding is relevant in that this novel approach might have implications with respect to impaired speech processing in dyslexics and older adults. PMID:26779822

  14. Flicker-Driven Responses in Visual Cortex Change during Matched-Frequency Transcranial Alternating Current Stimulation

    Science.gov (United States)

    Ruhnau, Philipp; Keitel, Christian; Lithari, Chrysa; Weisz, Nathan; Neuling, Toralf

    2016-01-01

    We tested a novel combination of two neuro-stimulation techniques, transcranial alternating current stimulation (tACS) and frequency tagging, that promises powerful paradigms to study the causal role of rhythmic brain activity in perception and cognition. Participants viewed a stimulus flickering at 7 or 11 Hz that elicited periodic brain activity, termed steady-state responses (SSRs), at the same temporal frequency and its higher order harmonics. Further, they received simultaneous tACS at 7 or 11 Hz that either matched or differed from the flicker frequency. Sham tACS served as a control condition. Recent advances in reconstructing cortical sources of oscillatory activity allowed us to measure SSRs during concurrent tACS, which is known to impose strong artifacts in magnetoencephalographic (MEG) recordings. For the first time, we were thus able to demonstrate immediate effects of tACS on SSR-indexed early visual processing. Our data suggest that tACS effects are largely frequency-specific and reveal a characteristic pattern of differential influences on the harmonic constituents of SSRs. PMID:27199707

  15. Atmospheric pressure chemical ionization of explosives using alternating current corona discharge ion source.

    Science.gov (United States)

    Usmanov, D T; Chen, L C; Yu, Z; Yamabe, S; Sakaki, S; Hiraoka, K

    2015-04-01

    The high-sensitive detection of explosives is of great importance for social security and safety. In this work, the ion source for atmospheric pressure chemical ionization/mass spectrometry using alternating current corona discharge was newly designed for the analysis of explosives. An electromolded fine capillary with 115 µm inner diameter and 12 mm long was used for the inlet of the mass spectrometer. The flow rate of air through this capillary was 41 ml/min. Stable corona discharge could be maintained with the position of the discharge needle tip as close as 1 mm to the inlet capillary without causing the arc discharge. Explosives dissolved in 0.5 µl methanol were injected to the ion source. The limits of detection for five explosives with 50 pg or lower were achieved. In the ion/molecule reactions of trinitrotoluene (TNT), the discharge products of NOx (-) (x = 2,3), O3 and HNO3 originating from plasma-excited air were suggested to contribute to the formation of [TNT - H](-) (m/z 226), [TNT - NO](-) (m/z 197) and [TNT - NO + HNO3 ](-) (m/z 260), respectively. Formation processes of these ions were traced by density functional theory calculations. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26149109

  16. Eyes wide shut: Transcranial alternating current stimulation drives alpha rhythm in a state dependent manner.

    Science.gov (United States)

    Ruhnau, Philipp; Neuling, Toralf; Fuscá, Marco; Herrmann, Christoph S; Demarchi, Gianpaolo; Weisz, Nathan

    2016-01-01

    Transcranial alternating current stimulation (tACS) is used to modulate brain oscillations to measure changes in cognitive function. It is only since recently that brain activity in human subjects during tACS can be investigated. The present study aims to investigate the phase relationship between the external tACS signal and concurrent brain activity. Subjects were stimulated with tACS at individual alpha frequency during eyes open and eyes closed resting states. Electrodes were placed at Cz and Oz, which should affect parieto-occipital areas most strongly. Source space magnetoencephalography (MEG) data were used to estimate phase coherence between tACS and brain activity. Phase coherence was significantly increased in areas in the occipital pole in eyes open resting state only. The lag between tACS and brain responses showed considerable inter-individual variability. In conclusion, tACS at individual alpha frequency entrains brain activity in visual cortices. Interestingly, this effect is state dependent and is clearly observed with eyes open but only to a lesser extent with eyes closed. PMID:27252047

  17. Matching bunched beams to alternating gradient focusing systems

    International Nuclear Information System (INIS)

    A numerical procedure for generating phase-space distributions matched to alternating gradient focusing systems has been tested. For a smooth-focusing system a matched distribution can be calculated. With a particle tracing simulation code such a distribution can be followed while adiabatically deforming the focusing forces until an alternating gradient configuration is reached. The distribution remains matched; that is, the final distribution is periodic with the structure period. This method is useful because it can produce distributions matched to nonlinear forces. This is a feature that elliptical distributions, with ellipse parameters obtained from the Courant-Snyder theory, do not have. External nonlinearities, including nonlinear couplings, were included in our examples but space charge was not. This procedure is expected to work with space charge but will require a three-dimensional space charge calculation in the simulation code

  18. Current Concept and Epidemiology of Systemic Vasculitides

    Directory of Open Access Journals (Sweden)

    Takayuki Katsuyama

    2014-01-01

    Full Text Available Although a new classification algorithm for systemic vasculitides was proposed by Watts et al. and the Chapel Hill Consensus Conference (CHCC was updated in 2012, there are currently no validated diagnostic criteria for systemic vasculitides. The Diagnostic and Classification Criteria for Vasculitis study (DCVAS is a global study to develop and improve the diagnostic criteria for systemic vasculitides. The epidemiology of systemic vasculitides differs widely among countries. For example, in the case of anti-neutrophil cytoplasmic antibody (ANCA-associated vasculitis, patients with microscopic polyangiitis (MPA and with positivity for MPO-ANCA are predominant in Asian countries, whereas patients with granulomatosis with polyangiitis (GPA and with positivity for PR3-ANCA are predominant in northern Europe and the United States. Interstitial lung disease (ILD occurs more frequently in Asian patients compared with patients in Europe. The incidence and the prevalence of large-vessel vasculitis also differ significantly. Giant cell arteritis (GCA occurs frequently in northern Europe, unlike Takayasu arteritis (TAK. The ethnic and regional differences in the incidence, prevalence and clinical characteristics of patients with vasculitis should be recognized when we diagnose and treat patients with vasculitis using criteria, and should also be considered when interpreting the results from clinical studies.

  19. Methodology for simulation of geomagnetically induced currents in power systems

    Directory of Open Access Journals (Sweden)

    Boteler David

    2014-07-01

    Full Text Available To assess the geomagnetic hazard to power systems it is useful to be able to simulate the geomagnetically induced currents (GIC that are produced during major geomagnetic disturbances. This paper examines the methodology used in power system analysis and shows how it can be applied to modelling GIC. Electric fields in the area of the power network are used to determine the voltage sources or equivalent current sources in the transmission lines. The power network can be described by a mesh impedance matrix which is combined with the voltage sources to calculate the GIC in each loop. Alternatively the power network can be described by a nodal admittance matrix which is combined with the sum of current sources into each node to calculate the nodal voltages which are then used to calculate the GIC in the transmission lines and GIC flowing to ground at each substation. Practical calculations can be made by superposition of results calculated separately for northward and eastward electric fields. This can be done using magnetic data from a single observatory to calculate an electric field that is a uniform approximation of the field over the area of the power system. It is also shown how the superposition of results can be extended to use data from two observatories: approximating the electric field by a linear variation between the two observatory locations. These calculations provide an efficient method for simulating the GIC that would be produced by historically significant geomagnetic storm events.

  20. A Comparison of Five Alternative Approaches to Information Systems Development

    Directory of Open Access Journals (Sweden)

    Rudy Hirschheim

    1997-11-01

    Full Text Available The field of information systems (IS has grown dramatically over the past three decades. Recent trends have transformed the IS landscape. These trends include: the evolution of implementation technology from centralized mainframe environments towards distributed client-server architectures, embracing the internet and intranets; changes in user interface technology from character-based to graphical user interfaces, multimedia, and the World Wide Web; changes in applications from transaction processing systems towards systems supporting collaborative work; and the use of information technology as an enabler of business process reengineering and redesign. These technology changes coupled with changes in organizations and their operating environment, such as the growth of the network and virtual organization, internationalization and globalization of many organizations, intensified global competition, changes in values such as customer orientation (service quality and Quality of Working Life, have imposed new demands on the development of information systems. These changes have led to an increasing discussion about information systems development (ISO, and in particular, the various methods, tools, methodologies, and approaches for ISD. We believe such discussion has opened the door for new, alternative IS development approaches and methodologies. Our paper takes up this theme by describing five alternative ISD approaches, namely the Interactionist approach, the Speech Act-based approach, Soft Systems Methodology, the Trade Unionist approach, and the Professional Work Practices approach. Despite the fact that most of these approaches have a history of over 15 years, their relevance to IS development is not well recognized in the mainstream of IS practice and research, nor is their institutional status comparable to traditional approaches such as structured analysis and design methods. Therefore we characterize the five approaches as 'alternative' in

  1. Alternate design of ITER cryostat skirt support system

    International Nuclear Information System (INIS)

    The skirt support of ITER cryostat is a support system which takes all the load of cryostat cylinder and dome during normal and operational condition. The present design of skirt support has full penetration weld joints at the bottom (shell to horizontal plate joint). To fulfill the requirements of tolerances and control the welding distortions, we have proposed to change the full penetration weld into fillet weld. A detail calculation is done to check the feasibility and structural impact due to proposed design. The calculations provide the size requirements of fillet weld. To verify the structural integrity during most severe load case, finite element analysis (FEA) has been done in line with ASME section VIII division 2. By FEA 'Plastic Collapse' and 'Local Failure' modes has been assessed. 5° sector of skirt clamp has been modeled in CATIA V5 R21 and used in FEA. Fillet weld at shell to horizontal plate joint has been modeled and symmetry boundary condition at ± 2.5° applied. 'Elastic Plastic Analysis' has been performed for the most severe loading case i.e. Category IV loading. The alternate design of Cryostat Skirt support system has been found safe by analysis against Plastic collapse and Local Failure Modes with load proportionality factor 2.3. Alternate design of Cryostat skirt support system has been done and validated by FEA. As per alternate design, the proposal of fillet weld has been implemented in manufacturing. (author)

  2. Susceptibility of CoFeB/AlOx/Co Magnetic Tunnel Junctions to Low-Frequency Alternating Current

    Directory of Open Access Journals (Sweden)

    Yuan-Tsung Chen

    2013-10-01

    Full Text Available This investigation studies CoFeB/AlOx/Co magnetic tunneling junction (MTJ in the magnetic field of a low-frequency alternating current, for various thicknesses of the barrier layer AlOx. The low-frequency alternate-current magnetic susceptibility (χac and phase angle (θ of the CoFeB/AlOx/Co MTJ are determined using an cac analyzer. The driving frequency ranges from 10 to 25,000 Hz. These multilayered MTJs are deposited on a silicon substrate using a DC and RF magnetron sputtering system. Barrier layer thicknesses are 22, 26, and 30 Å. The X-ray diffraction patterns (XRD include a main peak at 2θ = 44.7° from hexagonal close-packed (HCP Co with a highly (0002 textured structure, with AlOx and CoFeB as amorphous phases. The full width at half maximum (FWHM of the Co(0002 peak, decreases as the AlOx thickness increases; revealing that the Co layer becomes more crystalline with increasing thickness. χac result demonstrates that the optimal resonance frequency (fres that maximizes the χac value is 500 Hz. As the frequency increases to 1000 Hz, the susceptibility decreases rapidly. However, when the frequency increases over 1000 Hz, the susceptibility sharply declines, and almost closes to zero. The experimental results reveal that the mean optimal susceptibility is 1.87 at an AlOx barrier layer thickness of 30 Å because the Co(0002 texture induces magneto-anisotropy, which improves the indirect CoFeB and Co spin exchange-coupling strength and the χac value. The results concerning magnetism indicate that the magnetic characteristics are related to the crystallinity of Co.

  3. Expression of an alternative nitrogen fixation system in Azotobacter vinelandii.

    OpenAIRE

    Bishop, P E; Jarlenski, D M; Hetherington, D R

    1982-01-01

    Nitrogenase activities were determined from maximum acetylene reduction rates for mutant strains of Azotobacter vinelandii which are unable to fix N2 in the presence of molybdenum (Nif-) but undergo phenotypic reversal to Nif+ under conditions of Mo deficiency. The system responsible for N2 fixation under these conditions is thought to be an alternative N2 fixation system (Bishop et al., Proc. Natl. Acad. Sci. U.S.A. 77:7342-7346, 1980). Phenotypic reversal of Nif- strains to Nif+ strains was...

  4. Alternative drives for motor cars. Hybrid systems, fuel cells, alternative energy sources. 2. enl. ed.; Alternative Antriebe fuer Automobile. Hybridsysteme, Brennstoffzellen, alternative Energietraeger

    Energy Technology Data Exchange (ETDEWEB)

    Stan, Cornel [Berkeley Univ., CA (United States)]|[Paris Univ. (France)]|[Pisa Univ. (Italy)]|[Perugia Univ. (Italy)]|[Westsaechsischen Hochschule Zwickau (Germany)

    2008-07-01

    The implementation possibilities of future drive concepts - from hybrid systems comprising an electric motor and an internal combustion engine to fuel cells to alternative fuels like hydrogen or alcohol - will depend largely on quality criteria, e.g. power density, rotary momentum, acceleration characteristics, specific energy consumption, emissions of chemical substances, and noise. The boundary criteria for the introduction of realizeable concepts of alternative drives for motor cars will be defined by the availability and storability of the envisaged fuels, technical complexity, cost, safety, infrastructure and service. The book presents and analyzes the processes, drives and energy sources that can be combined in complex energy management systems for motor cars in accordance with the aforementioned criteria. Knowledge about these facts is indispensable for the development of new concepts. The 2nd edition describes many new developments in car propulsion systems as well as their combinations, new energy sources, energy converters and energy stores. All contents and literature reflect the latest state of science and technology. (orig.) [German] Ueber die Realisierungsmoeglichkeiten zukuenftiger Antriebskonzepte - von Hybridsystemen Elektro-/Verbrennungsmotor ueber Brennstoffzellen bis zu alternativen Energietraegern wie Wasserstoff oder Alkohol - werden fundierte Kriterien der Qualitaet eines Antriebs entscheiden. Leistungsdichte, Drehmomentverlauf, Beschleunigungscharakteristik, spezifischer Energieverbrauch sowie Emission chemischer Stoffe und Geraeusche sind dafuer wichtige Merkmale zur Qualitaetsbeurteilung. Die Verfuegbarkeit und die Speicherfaehigkeit vorgesehener Energietraeger, die technische Komplexitaet, Kosten, Sicherheit, Infrastruktur und Service werden die Randbedingungen fuer die Einfuehrung realisierbarer Konzepte alternativer Antriebe fuer Automobile stellen. Die Uebersicht und die Analyse der Prozesse, Antriebsmaschinen und Energietraeger, die

  5. California current system - Predators and the preyscape

    Science.gov (United States)

    Ainley, David G.; Adams, Peter B.; Jahncke, Jaime

    2015-06-01

    The preyscape of the California Current System (CCS), one of the most productive marine areas on Earth (Glantz and Thompson, 1981), is highly variable, as evidenced by the papers in this issue, and as such presents a challenge to Ecosystem-based fishery management (EBFM), which attempts to integrate ecosystem considerations as part of fishery management and conservation decisions. Approaches to EBFM for the waters off Washington, Oregon, and California, the CCS, have been initiated (PFMC, 2007, 2013), and are continually being developed. To inform this process, a workshop was held in September 2013 to: i) gather together the existing information on forage fish and predator dynamics in the CCS; ii) consider temporal (seasonal, annual, decadal) and spatial availability of prey complexes and why these patterns of availability occur and change; iii) summarize and present that information for discussion to a large range of experts in oceanography, fish and fisheries management, seabirds, marine mammals, and ecosystem management; and, iv) synthesize this information to be useable by fishery agencies. The papers in this special Journal of Marine Systems issue address these four points. While the full results and recommendations can be found here - "http://www.pointblue.org/uploads/assets/calcurrent/REPORT_Forage_Fish_Workshop_FINAL.pdf"

  6. Combined alternating gradient force magnetometer and susceptometer system.

    Science.gov (United States)

    Pérez, M; Ranchal, R; de Mendizábal Vázquez, I; Cobos, P; Aroca, C

    2015-01-01

    We report the design, fabrication, and characterization of a new system that combines the performances of two different types of magnetic characterization systems, Alternating Gradient Force Magnetometers (AGFM) and susceptometers. The flexibility of our system is demonstrated by its capability to be used as any of them, AGFM or susceptometer, without any modification in the experimental set-up because of the electronics we have developed. Our system has a limit of sensitivity lower than 5 × 10(-7) emu. Moreover, its main advantage is demonstrated by the possibility of measuring small quantities of materials under DC or AC magnetic fields that cannot properly be measured with a commercial vibrating sample magnetometers or AGFM. PMID:25638125

  7. Combined alternating gradient force magnetometer and susceptometer system

    International Nuclear Information System (INIS)

    We report the design, fabrication, and characterization of a new system that combines the performances of two different types of magnetic characterization systems, Alternating Gradient Force Magnetometers (AGFM) and susceptometers. The flexibility of our system is demonstrated by its capability to be used as any of them, AGFM or susceptometer, without any modification in the experimental set-up because of the electronics we have developed. Our system has a limit of sensitivity lower than 5 × 10−7 emu. Moreover, its main advantage is demonstrated by the possibility of measuring small quantities of materials under DC or AC magnetic fields that cannot properly be measured with a commercial vibrating sample magnetometers or AGFM

  8. Combined alternating gradient force magnetometer and susceptometer system

    Energy Technology Data Exchange (ETDEWEB)

    Pérez, M.; Mendizábal Vázquez, I. de; Aroca, C. [Dpto. Física Aplicada, E.T.S.I. Telecomunicación, Universidad Politécnica de Madrid, Ciudad Universitaria s/n, Madrid 28040 (Spain); Ranchal, R. [Dpto. Física de Materiales, Facultad Ciencias Físicas, Universidad Complutense de Madrid, Ciudad Universitaria s/n, Madrid 28040 (Spain); Cobos, P. [ISOM, Universidad Politécnica de Madrid, Ciudad Universitaria s/n, Madrid 28040 (Spain)

    2015-01-15

    We report the design, fabrication, and characterization of a new system that combines the performances of two different types of magnetic characterization systems, Alternating Gradient Force Magnetometers (AGFM) and susceptometers. The flexibility of our system is demonstrated by its capability to be used as any of them, AGFM or susceptometer, without any modification in the experimental set-up because of the electronics we have developed. Our system has a limit of sensitivity lower than 5 × 10{sup −7} emu. Moreover, its main advantage is demonstrated by the possibility of measuring small quantities of materials under DC or AC magnetic fields that cannot properly be measured with a commercial vibrating sample magnetometers or AGFM.

  9. Influence of a Transverse Electric Field on the Alternating Currents Rectification Effect in Superstructures with Non-additive Energy Spectrum

    Directory of Open Access Journals (Sweden)

    V.I. Konchenkov

    2015-12-01

    Full Text Available It is investigated the effect of mutual rectification of alternating currents, induced by an electric field of two uniformly polarized electromagnetic waves with different frequencies in two-dimensional superlattice with non-additive energy spectrum under the influence of a constant transverse electric field. The possibility of control of constant component of electric current (amplification, change of sign, suppression by the transverse electric field is shown. The abilities of the practical use of the results are discussed.

  10. Phase separation in carbon-doped MgB2 studied by means of alternating current susceptibility measurements

    International Nuclear Information System (INIS)

    Alternating-current susceptibility measurements were performed on ternary MgB2-xCx (0≤x≤0.1) superconducting compounds. The results are consistent with the presence of macroscopic phase inhomogeneities at extremely low levels of carbon doping (x≥0.04) in agreement with high-resolution synchrotron x-ray powder diffraction measurements. (author)

  11. Alternate suspension system for space shuttle avionics shelf

    Science.gov (United States)

    Biele, Frank H., III

    This thesis examines an equipment stowage shelf suspended from a frame in the cargo bay (mid fuselage) of the U.S. Space Shuttle, and three alternative designs. The first design is a conventional truss, representing the "tried and true" approach. The second is a cable dome type structure consisting of struts and pre-stressed cables. The third and fourth are double layer tensegrity systems consisting of contiguous struts of the order k=1 and k=2 respectively. The four options are compared to each other with an emphasis placed on weight, size, and approximate cost of each option. Results indicate the 4-Way Double Layer Tensegrity grid utilizing carbon fiber composite cables is the most efficient (lightest weight) tensegrity system, however for this particular application the most cost effective design was proven to be the optimized conventional truss. It was determined that the scale of the structure would have to increase substantially or tensegrity structures complexity must decrease for these alternative systems to compete with conventional designs.

  12. Integrated alternative energy systems for use in small communities

    Science.gov (United States)

    Thornton, J.

    1982-01-01

    This paper summarizes the principles and conceptual design of an integrated alternative energy system for use in typical farming communities in developing countries. A system is described that, utilizing the Sun and methane produced from crop waste, would supply sufficient electric and thermal energy to meet the basic needs of villagers for water pumping, lighting, and cooking. The system is sized to supply enough pumping capacity to irrigate 101 ha (249 acres) sufficiently to optimize annual crop yields for the community. Three economic scenarios were developed, showing net benefits to the community of $3,578 to $15,547 anually, payback periods of 9.5 to 20 years, and benefit-to-cost ratios of 1.1 to 1.9.

  13. Current-potential characteristics of electrochemical systems

    Energy Technology Data Exchange (ETDEWEB)

    Battaglia, V.S.

    1993-07-01

    This dissertation contains investigations in three distinct areas. Chapters 1 and 2 provide an analysis of the effects of electromagnetic phenomena during the initial stages of cell discharge. Chapter 1 includes the solution to Maxwell`s equations for the penetration of the axial component of an electric field into an infinitely long cylindrical conductor. Chapter 2 contains the analysis of the conductor included in a radial circuit. Chapter 3 provides a complete description of the equations that describe the growth of an oxide film. A finite difference program was written to solve the equations. The system investigated is the iron/iron oxide in a basic, aqueous solution. Chapters 4 and 5 include the experimental attempts for replacing formaldehyde with an innocuous reducing agent for electroless deposition. In chapter 4, current-versus-voltage curves are provided for a sodium thiosulfate bath in the presence of a copper disk electrode. Also provided are the cathodic polarization curves of a copper/EDTA bath in the presence of a copper electrode. Chapter 5 contains the experimental results of work done with sodium hypophosphite as a reducing agent. Mixed-potential-versus-time curves for solutions containing various combinations of copper sulfate, nickel chloride, and hypophosphite in the presence of a palladium disk electrode provide an indication of the reducing power of the solutions.

  14. Alternating current impedance spectroscopic analysis of biofunctionalized vertically-aligned silica nanospring surface for biosensor applications

    Science.gov (United States)

    Timalsina, Yukta P.

    In this dissertation, a process of vertically-aligned (silica) nanosprings (VANS) based biosensor development is presented. Alternating current (AC) impedance spectroscopy has been used to analyze sensor response as a function of saline phosphate (SP) buffer and biological solutions. The sensor is a parallel plate capacitor consisting of two glass substrates coated with indium tin oxide (ITO), where the VANS [or randomly-aligned nanosprings (RANS)] grown on one substrate serve as the dielectric spacer layer. The response of a VANS device as a function of ionic concentration in SP buffer was examined and an equivalent circuit model was developed. The results demonstrated that VANS sensors exhibited greater sensitivity to the changes in SP concentration relative to the ITO sensors, which serve as controls. The biofunctionalized VANS surface via physisorption and the cross-linker method demonstrates the repeatability, specificity, and selectivity of the binding. The physisorption of biotinylated immunoglobulin G (B-IgG) onto the VANS surface simplifies the whole sensing procedure for the detection of glucose oxidase, since the avidin-conjugated glucose oxidase (Av-GOx) can directly be immobilized on the B-IgG. The cross linker method involves the covalent attachment of antibodies onto the functionalized VANS surface via imine bond. The experiments revealed that the VANS sensor response is solely the result of the interaction of target molecule i.e. mouse IgG with the probe layer, i.e. goat antimouse IgG (GalphaM IgG). It was determined that VANS-based sensors exhibit a greater magnitude of change between successive bio-layers relative to the controls above 100 Hz, which indicates that the addition of biomolecules inhibits the diffusion of ions and changes the effective dielectric response of the VANS via biomolecular polarization. The study of ionic transport in nanosprings suggested that conductance follows a scaling law. It was demonstrated that a VANS-based device

  15. Alternating current thin film electroluminescence in the near infrared from zinc sulfide doped with rare earths

    Science.gov (United States)

    Kale, Ajay

    Near infrared emission (0.7--1.5 mum) of zinc sulfide (ZnS) doped with erbium (Er) or neodymium (Nd) has been studied in alternating current thin film electroluminescent devices (ACTFELDs). The electroluminescent (EL) thin film phosphors were radio frequency planar magnetron sputter deposited by co-sputtering an undoped ZnS target together with a ZnS: 1.5 mole% ErF 3 or ZnS: 1.5 mole% NdF3 target. The ZnS:ErF3 and ZnS:NdF3 thin film phosphors were annealed for one hour in ultra high purity N2 at temperatures ranging from 350--475°C. Annealing at 425°C for 1 hour in nitrogen was the optimal post-deposition treatment for both the ZnS:ErF3, and ZnS:NdF3 thin film phosphors, resulting in EL power densities of 7.5 and 28 muW/cm2 for the 990nm and the 1550nm emission of ZnS:ErF3, respectively. The power densities were 7.5 (750%) and 28 (2800%) times larger than those from the as-deposited films, which exhibited a power density ˜1muW/cm 2 at both wavelengths. In the case of ZnS:NdF3, 26 and 15 muW/cm2 deposited samples. Post-deposition annealing resulted in a 8 and 1.5 times increase in total device efficiency to 0.42 W/W and 0.7 W/W) for ZnS:ErF3 and ZnS:NdF3, respectively. This was attributed to a reduction in the concentration of shallow defects, which leads to a larger effective phosphor field and band bending, an increase in the conduction charge, and a reduction of inelastic scattering of ballistic electrons. While the peak emission wavelengths from Er were independent of annealing temperature, peak shifts were observed for Nd due to hybridization of the 5d-4f orbitals. At annealing temperatures 425°C, the shallow defect states are annealed out, leading to more efficient direct radiative relaxation from the higher lying excited states, and more intense visible luminescence is observed.

  16. Kilowatt Isotope Power System: component test report for the Ground Demonstration System Alternator Stator

    International Nuclear Information System (INIS)

    Results are presented of acceptance tests conducted on the Alternator Stator, S/N 002, for the Kilowatt Isotope Power System. These results show that the Alternator Stator, S/N 002 for the Kilowatt Isotope Power System has satisfactorily completed the testing set forth within Sundstrand Test Specification 2538. Test requirements of TS 2538 were extracted from the Kilowatt Isotope Power System, and Phase I Test Plan

  17. Accelerator-Driven System with Current Technology

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hee Seok; Lee, Tae Yeon [Pohang Accelerator Laboratory, Pohang (Korea, Republic of)

    2013-10-15

    World needs a safer and cleaner nuclear power plant. A nuclear power plant that will not cause a disaster and that will produce radiotoxic nuclear waste as small as possible. At the moment, the closest system is the accelerator driven system (ADS) making use of the Thorium fuel. First of all, it is safer in a disaster such as an earthquake, because the deriving accelerator stops immediately by the earthquake. And, there won't be a Fukushima-like accident, because this Thorium ADS reactor uses air cooling. It also minimizes the nuclear waste problem by reducing the amount of the toxic waste and shortening their half lifetime to only a few hundred years. Finally, it solves the Uranium reserve problem. The Thorium reserve is much larger than that of Uranium. Although the idea of ADS was proposed long time ago, it has not been utilized yet first by technical difficulty of accelerator. The accelerator-based system needs 0.6-1 GeV and at least a few MW power proton beam, which is an unprecedentedly high power. The most powerful 1 GeV proton linear accelerator is the Spallation Neutron Source, USA, which operates now at the power of 1.5 MW with the length of 350 m. A conventional linear accelerator would need several hundred m length, which is highly costly particularly in Korea because of the high land cost. Another difficulty is reliability of accelerator operation. To be used as a power plant facility, accelerator should obviously operate such that the power plant may continuously generate electricity at least for months with no interruption. However, the reality is that a high power proton accelerator is hardly operated even a few hours without interruption, although very short interruptions are tolerable. Anyway, it will take a time to develop an accelerator sufficiently reliable to be used for power generation. Now the question is if it is possible to realize ADS with the current level of accelerator technology. This paper seeks the possibility.

  18. Accelerator-Driven System with Current Technology

    International Nuclear Information System (INIS)

    World needs a safer and cleaner nuclear power plant. A nuclear power plant that will not cause a disaster and that will produce radiotoxic nuclear waste as small as possible. At the moment, the closest system is the accelerator driven system (ADS) making use of the Thorium fuel. First of all, it is safer in a disaster such as an earthquake, because the deriving accelerator stops immediately by the earthquake. And, there won't be a Fukushima-like accident, because this Thorium ADS reactor uses air cooling. It also minimizes the nuclear waste problem by reducing the amount of the toxic waste and shortening their half lifetime to only a few hundred years. Finally, it solves the Uranium reserve problem. The Thorium reserve is much larger than that of Uranium. Although the idea of ADS was proposed long time ago, it has not been utilized yet first by technical difficulty of accelerator. The accelerator-based system needs 0.6-1 GeV and at least a few MW power proton beam, which is an unprecedentedly high power. The most powerful 1 GeV proton linear accelerator is the Spallation Neutron Source, USA, which operates now at the power of 1.5 MW with the length of 350 m. A conventional linear accelerator would need several hundred m length, which is highly costly particularly in Korea because of the high land cost. Another difficulty is reliability of accelerator operation. To be used as a power plant facility, accelerator should obviously operate such that the power plant may continuously generate electricity at least for months with no interruption. However, the reality is that a high power proton accelerator is hardly operated even a few hours without interruption, although very short interruptions are tolerable. Anyway, it will take a time to develop an accelerator sufficiently reliable to be used for power generation. Now the question is if it is possible to realize ADS with the current level of accelerator technology. This paper seeks the possibility

  19. Alternative irradiation system for efficiency manganese bath determination

    International Nuclear Information System (INIS)

    The Manganese Sulphate Bath (MSB) is the main method used in most metrological laboratories to measure the neutron sources emission rate Q(t) . The MSB technique consists, basically, in dipping a neutron source in the center of a large tank (∼500 L) containing a concentrated aqueous solution of manganese sulphate. The neutron source emission rate is determined through the activity solution measurement produced by captured neutrons in manganese nuclei. In order to obtain the value of Q(t) it must be taken into account the detection system efficiency and still determine some corrections. The MSB system efficiency is usually determined by irradiating a solution sample from MSB system in a reactor or accelerator. This paper proposes an alternative irradiation system (Irradiation Bath), which works with a radionuclide neutron source and manganese sulphate solution volume for efficiency determination of MSB system. This irradiation system was designed by simulation with MCNP code, considering a californium neutron source in several manganese sulphate volumes and different neutron reflectors. The goal of this simulation was to determine the materials and dimensions of Irradiation Bath which will derive the maximum manganese neutron capture. Although the specific activated irradiated samples are less than those in reactors, the simulation results for optimized Irradiation Bath have showed a manganese neutron capture increase up to 100 times with dimensions less than 15 cm in diameter when it compared to manganese neutron capture in a MSB System whose diameter is about 100 cm . (author)

  20. Justice Dispensation through the Alternative Dispute Resolution System in India

    Directory of Open Access Journals (Sweden)

    Krishna Agrawal

    2015-02-01

    Full Text Available The Law Commission of India in its 222nd report emphasized the need for Alternative Disputes Resolution (ADR for the dispensation of justice, because the courts are inaccessible owing to various factors, e.g., poverty, social and political backwardness, illiteracy, ignorance, procedural formalities and inordinate delay in judgments. During the ancient period the disputes were resolved in an informal manner by neutral third persons or people’s court in villages and it continued till the middle of the 20th century. Unfortunately, after the Independence of India in 1947, this system was dissuaded and the government permitted to continue the adversarial system of justice. In 1980, a committee was set up. It recommended Lok Adalats (People’s Courts. In 1987, the Legal Services Authorities Act was enacted. This Act obligates the states to provide free legal aid to poor persons. Besides this, the Act provides for the establishment of permanent Lok Adalats.This is one of the important modes of ADR. Lok Adalats have been established in all the districts of the country. They bring conciliatory settlement in complicated cases arising out of matrimonial, landlord-tenants, property, insurance and commercial disputes. There are four methods of ADR, viz., negotiation, mediation, conciliation and arbitration. Mediation and arbitration are widely preferred. They are alternatives to litigation. The Arbitration Act for the first time was enacted in 1889 and it was subsequently amended many times. On the objections raised by the Supreme Court of India and also on the adoption of UNCITRAL Model Law on International Commercial Arbitration, in 1996 Arbitration and Conciliation Act was enacted. This law is almost the same as is almost in all the countries.Further, the Government of India established International Centre for Alternative Disputes Resolution (CADR with the objectives of promotion, propagation, and popularizing the settlement of domestic and

  1. Condition responsive truck rollover warning systems: Alternative system designs

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, S. [Oak Ridge National Lab., TN (United States); Richards, S.H. [Univ. of Tennessee, Knoxville, TN (United States). Transportation Research Center

    1997-10-01

    Truck rollover is a serious highway safety problem, with consequences that make the occurrences important despite their relative infrequency. Truck accidents on urban freeways occur more frequently at interchange off-ramps that at any other location, accounting for about 5% of fatal truck accidents, according to accident statistics summarized in a study performed by Bellomo-McGee, Inc., for FHWA. Severe traffic disruption often results from truck rollover, and the severity of incidents can be sorely multiplied by the type of cargo the truck is hauling. Some hazardous cargos have the potential to cause true disaster is they are spilled as a result of truck rollover. Because of the severity of consequences of truck rollover accidents, it is important to seek ways to avoid such accidents. In the near-term future, the most likely means to prevent such rollover accidents is a condition responsive system that can warn truck drivers of impending rollover in time for them to take corrective actions.

  2. Selection of alternative material for common rail direct injection system

    OpenAIRE

    Senguttuvan, N.; Raja, S; R. Sasidharan

    2014-01-01

    Common rail direct fuel injection is a modern variant of direct fuel injection system for petrol and diesel engines. The common rail system prototype was developed in the late 1960s by Robert Huber of Switzerland and the technology further developed by Dr. Marco. In petrol engine MPFI technology was developed and implemented in earlier days. Basically common rail tube was fabricated by steel for petrol engines. In the current study Steel, Brass, Aluminum alloy a356 and ABS materials were anal...

  3. Study of an alternative system for manganese bath efficiency determination

    International Nuclear Information System (INIS)

    An alternative irradiation system, using radioisotope neutron sources and a small MnSO4 solution volume, was proposed m this work to determine the Manganese Bath System (MBS) efficiency. The irradiation system was characterized through simulations with the MCNP radiation transport code from the modeling of 252Cf(f,n) and 238PuBe(alpha,n) neutron sources in several MnSO4 solution volumes and different neutron reflector medium for this solution. The parameter calculated in the simulations was the manganese neutron specific capture (MNSC), which is related to the MnSO4 solution specific activity. From the proposed systems for 252Cf (f, n) and 238PuBe (alpha,n) the NSCM was increased hundred times, in relation with that achieved in the LN/LNMRI/IRD MBS system simulation when irradiated by each these neutron sources. During study for irradiation system characterization its concept was verified using a assemble of test irradiation (ATI), which were spherical glass cavities, with few centimeter in radius, filled with MnSO4 solution, with and without presence of a neutron reflector medium. These TIA were used in four efficiency measurements and the average value was obtained. (author)

  4. Alternative Suspension System for Space Shuttle Avionics Shelf

    Science.gov (United States)

    Biele, Frank H., III

    2010-01-01

    Engineers working in the Aerospace field under deadlines and strict budgets often miss the opportunity to design something that is considered new or innovative, favoring instead to use the tried-and-true design over those that may, in fact, be more efficient. This thesis examines an electronic equipment stowage shelf suspended from a frame in the cargo bay (mid fuselage) of the United States Space Transportation System (STS), the Space Shuttle, and 3 alternative designs. Four different designs are examined and evaluated. The first design is a conventional truss, representing the tried and true approach. The second is a cable dome type structure consisting of struts and pre-stressed wiring. The third and fourth are double layer tensegrity systems consisting of contiguous struts of the order k=1 and k=2 respectively.

  5. Energy absorbing supports - an alternative piping support system

    International Nuclear Information System (INIS)

    An extensive development effort has resulted in the successful application of energy absorbers as alternative supports. Several installations of energy absorbers demonstrating the feasibility of this support concept have been successfully completed. Designed in accordance with the ASME Code Case N-420, these ductile supports undergo limited and controlled yielding under dynamic conditions, thereby dissipating energy. The design methodology determines the specific damping ratios applicable for a given piping system on the basis of the energy absorbers used. Thus, using energy absorbers permits predictable damping to be engineered into the system desing. They can be used in operating plants to replace existing snubbers. In plants under construction, they can be used in place of both snubbers and rigid supports. In both applications, fewer energy absorbers are required as compared to snubbers and rigid supports. (orig.)

  6. Energy absorbing supports - An alternative piping support system

    International Nuclear Information System (INIS)

    An extensive development effort has resulted in the successful application of energy absorbers as alternative supports. Several installations of energy absorbers demonstrating the feasibility of this support concept have been successfully completed. Designed in accordance with the ASME Code Case N-420, these ductile supports undergo limited and controlled yielding under dynamic conditions, thereby dissipating energy. The design methodology determines the specific damping ratios applicable for a given piping system on the basis of the energy absorbers used. Thus, using energy absorbers permits predictable damping to be engineered into the system design. They can be used in operating plants to replace existing snubbers. In plants under construction, they can be used in place of both snubbers and rigid supports. In both applications, fewer energy absorbers are required as compared to snubbers and rigid supports

  7. Total System Performance Assessment: Enhanced Design Alternative IV

    Energy Technology Data Exchange (ETDEWEB)

    P.D. Mattie

    1999-06-23

    The purpose of this calculation is to document total system performance assessment modeling of Enhanced Design Alternative (EDA) Feature IV. Total System Performance Assessment (TSPA) calculations for EDA IV are based on the TSPA-VA Base Case which has been modified with a quartz sand invert, quartz sand backfill, line loading and 21 PWR waste packages that have 2-cm thick titanium grade 7 corrosion resistant material (CRM) drip shields that are placed over a 30 cm thick carbon steel (A5 16) waste package with an integral filler material (CRWMS M&O 1999a & 1999b). This document details the changes and assumptions made to the VA reference Performance Assessment Model (CRWMS M&O 1998a) to incorporate the design changes detailed for EDA IV. The performance measure for this evaluation is the expected value dose-rate history at 20 km from the repository boundary.

  8. Space Industry Commercialization: A Systems Engineering Evaluation of Alternatives

    Science.gov (United States)

    Dinally, Jihan

    The Constellation Program cancellation reversed the government and commercial space industry's roles and relationships by dedicating the majority of the federal funding and opportunities to the commercial space industry and left the government space industry in search of an approach to collaborate with the dominant organization, the commercial space industry service providers. The space industry government agencies, Air Force Space Command (AFSPC) and National Aeronautics and Space Administration (NASA) had realized that to gain resources in the new commercially oriented economic environment, they had to work together and possess the capabilities aligned with the National Space Policy's documented goals. Multi-organizational collaboration in space industry programs is challenging, as NASA, AFSPC, and commercial providers, follow different [1] enterprise architecture guidance such as the NASA systems engineering Handbook, MIL-STD-499 and "A Guide to the systems engineering Body of Knowledge" by the International Council on systems engineering [2] [3]. A solution to streamline their enterprise architecture documentation and meet National Space Policy goals is the Multi-User Architecture Maturity Model Methodology (MAM3), which offers a tailored systems engineering technique the government agencies and private companies can implement for the program's maturity level. In order to demonstrate the MAM3, a CubeSat motivated study was conducted partnering a commercial provider with a government agency. A survey of the commercial space industry service providers' capabilities was performed to select the private companies for the study. Using the survey results, the commercial space industry service providers were ranked using the Analytic Hierarchy Process (AHP) [4]. The AHP is a structured technique for making complex decisions for representing and quantifying its weights, relating those weights to overall goals, and evaluating alternative solutions [5] - [8]. The weights

  9. Including alternative resources in state renewable portfolio standards: Current design and implementation experience

    International Nuclear Information System (INIS)

    As of October 2012, 29 states, the District of Columbia, and Puerto Rico have instituted a renewable portfolio standard (RPS). Each state policy is unique, varying in percentage targets, timetables, and eligible resources. Increasingly, new RPS polices have included alternative resources. Alternative resources have included energy efficiency, thermal resources, and, to a lesser extent, non-renewables. This paper examines state experience with implementing renewable portfolio standards that include energy efficiency, thermal resources, and non-renewable energy and explores compliance experience, costs, and how states evaluate, measure, and verify energy efficiency and convert thermal energy. It aims to gain insights from the experience of states for possible federal clean energy policy as well as to share experience and lessons for state RPS implementation. - Highlights: • Increasingly, new RPS policies have included alternative resources. • Nearly all states provide a separate tier or cap on the quantity of eligible alternative resources. • Where allowed, non-renewables and energy efficiency are being heavily utilized

  10. EVALUATION OF CURRENTLY AVAILABLE ALTERNATIVES TO METHYL BROMIDE FOR ORNAMENTAL CROP PRODUCTION IN FLORIDA

    Science.gov (United States)

    Studies were designed to test the efficacy of the chemical alternatives, Midas™ (iodomethane:chloropicrin (pic) 50:50 [MI 50:50] and 98:2 [MI 98:2], Arysta LifeScience Corp., Cary, NC) and dimethyl disulfide:pic (Paladin™ 79:21 [DMDS], United Phosphorous, Inc., King of Prussia, PA) compared with met...

  11. Superconducting Current Leads for Cryogenic Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Space flight cryocoolers will be able to handle limited heat loads at their expected operating temperatures and the current leads may be the dominant contributor to...

  12. BUCCAL DRUG DELIVERY SYSTEM: THE CURRENT INTEREST

    Directory of Open Access Journals (Sweden)

    Patel Mitul

    2011-12-01

    Full Text Available This review highlights the several advantages of buccal drug delivery system (BDDS over the conventional and systemic formulation majorly. It helps to enhance bioavailability through bypassing the first pass metabolism. On this drug delivery system the formulation keeps in contact with the mucosal surface resulting in better absorption and prolonged resident time. Though all drugs are not suitable for this drug delivery system yet is useful for most of the drugs. Bioadhesive polymers roles a major part in this drug delivery system because the extent of Mucoadhesion is a very important phenomena for the buccal drug delivery system. This review covers merits and demerits of buccal drug delivery system, anatomy of oral mucosa, mechanism of drug permeation, polymers and permeation enhancer used in buccal drug delivery system. This review also covers available marketed product as buccal drug delivery system and future aspects of buccal drug delivery system.

  13. Feedback-Controlled Transcranial Alternating Current Stimulation Reveals a Functional Role of Sleep Spindles in Motor Memory Consolidation.

    Science.gov (United States)

    Lustenberger, Caroline; Boyle, Michael R; Alagapan, Sankaraleengam; Mellin, Juliann M; Vaughn, Bradley V; Fröhlich, Flavio

    2016-08-22

    Transient episodes of brain oscillations are a common feature of both the waking and the sleeping brain. Sleep spindles represent a prominent example of a poorly understood transient brain oscillation that is impaired in disorders such as Alzheimer's disease and schizophrenia. However, the causal role of these bouts of thalamo-cortical oscillations remains unknown. Demonstrating a functional role of sleep spindles in cognitive processes has, so far, been hindered by the lack of a tool to target transient brain oscillations in real time. Here, we show, for the first time, selective enhancement of sleep spindles with non-invasive brain stimulation in humans. We developed a system that detects sleep spindles in real time and applies oscillatory stimulation. Our stimulation selectively enhanced spindle activity as determined by increased sigma activity after transcranial alternating current stimulation (tACS) application. This targeted modulation caused significant enhancement of motor memory consolidation that correlated with the stimulation-induced change in fast spindle activity. Strikingly, we found a similar correlation between motor memory and spindle characteristics during the sham night for the same spindle frequencies and electrode locations. Therefore, our results directly demonstrate a functional relationship between oscillatory spindle activity and cognition. PMID:27476602

  14. CURRENT TRENDS IN PULSATILE DRUG DELIVERY SYSTEMS

    OpenAIRE

    S. R. Tajane et al.

    2012-01-01

    The purpose for this review on pulsatile drug delivery systems (PDDS) is to compile the recent literatures with special focus on the different types and approaches involved in the development of the formulation. Pulsatile drug delivery system is the most interesting time and site-specific system. This system is designed for chronopharmacotherapy. Thus, to mimic the function of living systems and in view of emerging chronotherapeutic approaches, pulsatile delivery, which is meant to release a ...

  15. local alternative sources for cogeneration combined heat and power system

    Science.gov (United States)

    Agll, Abdulhakim Amer

    Global demand for energy continues to grow while countries around the globe race to reduce their reliance on fossil fuels and greenhouse gas emissions by implementing policy measures and advancing technology. Sustainability has become an important issue in transportation and infrastructure development projects. While several agencies are trying to incorporate a range of sustainability measures in their goals and missions, only a few planning agencies have been able to implement these policies and they are far from perfect. The low rate of success in implementing sustainable policies is primarily due to incomplete understanding of the system and the interaction between various elements of the system. The conventional planning efforts focuses mainly on performance measures pertaining to the system and its impact on the environment but seldom on the social and economic impacts. The objective of this study is to use clean and alternative energy can be produced from many sources, and even use existing materials for energy generation. One such pathway is using wastewater, animal and organic waste, or landfills to create biogas for energy production. There are three tasks for this study. In topic one evaluated the energy saving that produced from combined hydrogen, heat, and power and mitigate greenhouse gas emissions by using local sustainable energy at the Missouri S&T campus to reduce energy consumption and fossil fuel usage. Second topic aimed to estimate energy recovery and power generation from alternative energy source by using Rankin steam cycle from municipal solid waste at Benghazi-Libya. And the last task is in progress. The results for topics one and two have been presented.

  16. Alternative system design concepts for the ITER core CXRS upper port plug front end

    International Nuclear Information System (INIS)

    Highlights: → System design for the core CXRS diagnostic port plug for ITER is investigated. → Dependencies of the sub-systems are given. → Overall system lifetime and recent mechanical changes are taken into account. → System configurations are derived for the current ITER design. - Abstract: The upper port no. 3 in ITER will be used by the core Charge Exchange Recombination Spectroscopy (core CXRS) to channel out light from the inside of the vacuum vessel. Recent research about the lifetime of the first two mirrors and changes in the upper port plug geometry initiated further investigations into possible alternative system design concepts. Two new variants of the optical system were chosen for further investigation. The different sub-systems of core CXRS such as optical system, retractable tube and shutter are introduced together with their impact on the system design and their interactions. Space constraints originating from the envelope of the UPP and requirements emerging from the ITER environment such as remote handling and other maintenance considerations are also included in the investigation. Alternative system concepts taking the constraints into account are presented and discussed. Implications for further design work on the subsystems are derived from the results.

  17. Advanced transportation system studies. Alternate propulsion subsystem concepts: Propulsion database

    Science.gov (United States)

    Levack, Daniel

    1993-01-01

    The Advanced Transportation System Studies alternate propulsion subsystem concepts propulsion database interim report is presented. The objective of the database development task is to produce a propulsion database which is easy to use and modify while also being comprehensive in the level of detail available. The database is to be available on the Macintosh computer system. The task is to extend across all three years of the contract. Consequently, a significant fraction of the effort in this first year of the task was devoted to the development of the database structure to ensure a robust base for the following years' efforts. Nonetheless, significant point design propulsion system descriptions and parametric models were also produced. Each of the two propulsion databases, parametric propulsion database and propulsion system database, are described. The descriptions include a user's guide to each code, write-ups for models used, and sample output. The parametric database has models for LOX/H2 and LOX/RP liquid engines, solid rocket boosters using three different propellants, a hybrid rocket booster, and a NERVA derived nuclear thermal rocket engine.

  18. 17 CFR 242.302 - Recordkeeping requirements for alternative trading systems.

    Science.gov (United States)

    2010-04-01

    ... alternative trading systems. 242.302 Section 242.302 Commodity and Securities Exchanges SECURITIES AND... SECURITY FUTURES Regulation Ats-Alternative Trading Systems § 242.302 Recordkeeping requirements for alternative trading systems. To comply with the condition set forth in paragraph (b)(8) of § 242.301,...

  19. 17 CFR 242.303 - Record preservation requirements for alternative trading systems.

    Science.gov (United States)

    2010-04-01

    ... requirements for alternative trading systems. 242.303 Section 242.303 Commodity and Securities Exchanges... REQUIREMENTS FOR SECURITY FUTURES Regulation Ats-Alternative Trading Systems § 242.303 Record preservation requirements for alternative trading systems. (a) To comply with the condition set forth in paragraph (b)(9)...

  20. Promising freeze protection alternatives in solar domestic hot water systems

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, D.E.

    1997-12-31

    Since the gains associated with solar thermal energy technologies are comparatively small in relation to the required capital investment, it is vital to maximize conversion efficiency. While providing the necessary function of freeze protection, the heat exchanger commonly included in solar domestic water heating systems represents a system inefficiency. This thesis explores two alternate methods of providing freeze protection without resorting to a heat exchanger. Commonly, collectors are made of rigid copper tubes separated by copper or aluminum fins. Cracking damage can occur when water is allowed to freeze and expand inside the non compliant tubes. The possibility of making collectors out of an elastic material was investigated and shown to be effective. Since unlike copper, elastomers typically have low thermal conductivities, the standard collector performance prediction equations do not apply. Modified thermal performance prediction equations were developed which can be used for both low and high thermal conductivity materials to provide accurate predictions within a limited range of plate geometries. An elastomeric collector plate was then designed and shown to have comparable performance to a copper plate collector whose aperture area is approximately 33% smaller. Another options for providing freeze protection to an SDHW system is to turn it off during the winter. Choosing a three-season operating period means two things. First, the system will have different optimums such as slope and collector area. Second, the wintertime solar energy incident on the collector is unavailable for meeting a heating load. However, the system`s heat exchanger becomes unnecessary and removing it increases the amount of energy that arrives at the storage tank during those periods in which the system is operating.

  1. BUCCAL DRUG DELIVERY SYSTEM: THE CURRENT INTEREST

    OpenAIRE

    Patel Mitul; Karigar Asif; Savaliya Pratik; Ramana MV; Dubal Ashwini

    2011-01-01

    This review highlights the several advantages of buccal drug delivery system (BDDS) over the conventional and systemic formulation majorly. It helps to enhance bioavailability through bypassing the first pass metabolism. On this drug delivery system the formulation keeps in contact with the mucosal surface resulting in better absorption and prolonged resident time. Though all drugs are not suitable for this drug delivery system yet is useful for most of the drugs. Bioadhesive polymers roles a...

  2. Validation and quality control of replacement alternatives ?€“ current status and future challenges

    OpenAIRE

    Leist, Marcel; Hasiwa, Nina; Daneshian, Mardas; Hartung, Thomas

    2012-01-01

    Alternatives to animal testing have been developed mainly in the fields of toxicology and vaccine testing. Typical examples are the evaluation of phototoxicity, eye irritation or skin corrosion/irritation of cosmetics and industrial chemicals. However, examples can also be found in other biomedical areas, such the control of the quality of drug preparations for pyrogens or for the control of the production process of biologics, such as botulinum neurotoxin. For regulatory purposes, the qualit...

  3. Characterization of Alternative Hybrid Solar Thermal Electric Systems

    International Nuclear Information System (INIS)

    Hybrid power towers offer a number of advantages over solar-only power tower systems for early commercial deployment of the technology. These advantages include enhanced modularity, reduced financial and technical risks, and lower energy costs. With the changes in the domestic and world markets for bulk power, hybrid power towers are likely to have the best opportunities for power projects. This paper discusses issues that are likely to be important to the deployment of hybrid power towers in the near future. A large number of alternative designs are possible, and it is likely that there is no single approach that can be considered best or optimal for all project opportunities. The preferred design will depend on the application, as well as the unique objectives and perspectives of the person evaluating the design

  4. Current Mode Data Converters for Sensor Systems

    DEFF Research Database (Denmark)

    Jørgensen, Ivan Herald Holger

    This thesis is mainly concerned with data conversion. Especially data conversion using current mode signal processing is treated.A tutorial chapter introducing D/A conversion is presented. In this chapter the effects that cause static and dynamic nonlinearities are discussed along with methods to...

  5. Oxygen bubble development on a platinum electrode in borosilicate glass melt by the effect of alternating current

    Czech Academy of Sciences Publication Activity Database

    Matěj, J.; Jebavá, Marcela

    2014-01-01

    Roč. 58, č. 4 (2014), s. 249-259. ISSN 0862-5468 R&D Projects: GA TA ČR TA01010844 Institutional support: RVO:67985891 Keywords : glass melt * platinum electrode * alternating current * oxygen bubble Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass Impact factor: 0.435, year: 2014 http://www.ceramics-silikaty.cz/2014/pdf/2014_04_249.pdf

  6. Overview of Alternative Bunching and Current-shaping Techniques for Low-Energy Electron Beams

    Energy Technology Data Exchange (ETDEWEB)

    Piot, Philippe [Northern Illinois U.

    2015-12-01

    Techniques to bunch or shape an electron beam at low energies (E <15 MeV) have important implications toward the realization of table-top radiation sources [1] or to the design of compact multi-user free-electron lasers[2]. This paper provides an overview of alternative methods recently developed including techniques such as wakefield-based bunching, space-charge-driven microbunching via wave-breaking [3], ab-initio shaping of the electron-emission process [4], and phase space exchangers. Practical applications of some of these methods to foreseen free-electron-laser configurations are also briefly discussed [5].

  7. Alternating current for the West; Un courant alternatif pour le grand ouest

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    In the framework of the reactor EPR construction in the Manche, the authors wonder on the pertinence of this energy choice for the economy and the environment of the West France. They show that there is an alternative to this choice. In a first part a state of the situation concerning the electricity supply and demand in the region is detailed. Then from the local potential of renewable electric power production and the electricity conservation, they propose many concrete actions. (A.L.B.)

  8. Regional economic effects of current and proposed management alternatives for Sand Lake National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report first provides a description of the local community and economy near Sand Lake NWR. An analysis of current and proposed management strategies that could...

  9. Alternative BWR plant shutdown system using fire protection system and containment vent

    International Nuclear Information System (INIS)

    In certain severe accidents, caused by factors beyond the plant design bases, a loss of operability in the systems normally used to attain safe shutdown of the plant could occur. For such situations, Cofrentes NPP has carried out a series of studied and modifications that aim to attain safe shutdown using alternative systems which have their own power supply systems and are not dependent on external or emergency networks. These alternative systems include some existing plant systems (fire protection system, FPS) which have been validated to perform new operations, as well as other systems wich have been developed recently (containment venting system, CVS). Reactor cooling is restored through the injection of water using the FPS system (diesel pump), and the residual heat removal function is performed by discharging water through the relief valves into the suppression pool and from there into the external atmosphere by means of the CVS. (Author) 6 refs

  10. Transition challenges for alternative fuel vehicle and transportation systems

    OpenAIRE

    Jeroen Struben; John D. Sterman

    2008-01-01

    Automakers are now developing alternatives to internal combustion engines (ICE), including hydrogen fuel cells and ICE – electric hybrids. Adoption dynamics for alternative vehicles are complex, owing to the size and importance of the auto industry and vehicle installed base. Diffusion of alternative vehicles is both enabled and constrained by powerful positive feedbacks arising from scale and scope economies, research and development, learning by doing, driver experience, word of mouth, and ...

  11. Determination of aniline in environmental water samples by alternating-current oscillopolarographic titration

    Institute of Scientific and Technical Information of China (English)

    Jun Ping Xiao; Qing Xiang Zhou; Xiao Ke Tian; Hua Hua Bai; Xian Fa Su

    2007-01-01

    A new method for the determination of aniline in environmental water based on oscillopolarographic titration was presented in this paper.Several factors including the kind, concentration, and volume of acid, the dosage of potassium bromide, the temperature and concentration of concomitant substances were investigated in detail.The experimental results indicated that this method was simple, rapid, and sensitive.The linear range was 8.367 x 10-4 to 2.789 x 10-2 mol L-1, the relative standard deviation (R.S.D.) was lower than 0.96%, and the spiked recoveries of aniline in environmental water samples were in the range of 99.4-106.9% under the optimal conditions.The results indicated that the present method could be used as an alternative method for aniline determination in realworld water samples.

  12. Characterization of CdS thin films electrodeposited by an alternating current electrolysis method

    International Nuclear Information System (INIS)

    Conventional electrochemical methods of making CdS films are anodic oxidation of cadmium in a solution containing sulfide ions, and cathodic reduction from solutions containing soluble metal and sulfur compounds. In this paper a method is presented in which a CdS layer is deposited by a.c. electrolysis. The substrate is a glass plate covered by a layer of tin oxide. The electrolyte is an aqueous solution containing cadmium sulphate, ammonium sulphate, sodium thiosulphate, sodium chloride and glycerol. The applied a.c. voltages correspond to symmetrical and asymmetrical rectangular waves. During the electrolysis two electrodes are alternately connected to positive and negative potentials. As a result, Cd/sup 2+/ and S/sup 2-/ particles deposit at each electrode by turns, which results in the formation of a CdS layer

  13. Research of resisting of the biological active point for constant and alternative current

    Directory of Open Access Journals (Sweden)

    S. N. Peregudov

    2008-05-01

    Full Text Available Is conducted research of resistance of biologically active point (BAT on a direct and variable current. Research results are presented. The estimation of intercommunication between resistance of skin and by an electromagnetic radiation in BAT is done. Is shown possibility of the use of experimental information for diagnostics of the state of human to the organism.

  14. Use of Superimposed Alternating Currents in Quadrupoles to Measure Beam Position with Respect to their Magnetic Centre

    CERN Document Server

    Marks, N

    2000-01-01

    The positional stability of the electron beam in a modern state-of-the-art synchrotron radiation source is critical, as the many experimental users require consistency in the position and dimensions of the incoming photon beams which are incident on their experimental samples. At the Daresbury Synchrotron Radiation Source (SRS), inaccuracies in the measurements of the positions of both beam position monitors and the lattice quadrupoles can be overcome by measuring the position of the electron beam with respect to the magnetic centres of the quadrupoles. This was achieved by superimposing an alternating ('ripple') current on the direct current excitation of a single lattice quadrupole and examining the resulting beam oscillations at remote positions in the storage ring. If the electron beam is then subjected to a local distortion at the position of this quadrupole, the amplitude of the beam oscillation induced by the superimposed current is minimised (nominally zero) when the beam is at the quadrupole's magnet...

  15. Current guidelines for the laboratory diagnosis of thyroid diseases (radioimmunoassay and alternative immunoassays)

    International Nuclear Information System (INIS)

    The improvements in the sensitivity and specificity of biochemical thyroid tests have dramatically impacted clinical strategies for diagnosis and treating thyroid disorders. This article is designed to give an overview of the current strengths and limitations of the in vitro thyroid tests most commonly used in clinical practice. Despite recent methodological achievements, current thyroid tests still exhibit wide variability and are prone to a variety of technical limitations of which physicians are often unaware. Such problems include binding protein abnormalities that affect the FT4 tests, thyroglobulin autoantibodies that interfere with serum Tg measurement, medications or sever non thyroid illness that have myriad effects on thyroid tests. It is recommended that an active laboratory-physician interface be maintained to ensure that quality, cost-effective assays are used in a logical sequence and to assess abnormal thyroid test results and investigate discordance. These discordance need to be interpreted with care using a collaborative approach between laboratory and physicians. (author)

  16. Total System Performance Assessment: Enhanced Design Alternative V

    International Nuclear Information System (INIS)

    This calculation documents the total system performance assessment modeling of Enhanced Design Analysis (EDA) V. EDA V is based on the TSPA-VA base design which has been modified with higher thermal loading, a quartz sand invert, and line loading with 21 PWR waste packages that have 2-cm thick titanium grade 7 corrosion resistance material (CRM) drip shields placed over dual-layer waste packages composed of 'inside out' VA reference material (CRWMS M and O 1999a). This document details the changes and assumptions made to the VA reference Performance Assessment Model (CRWMS M and O 1998a) to incorporate the design changes detailed for EDA V. The performance measure for this evaluation is expected value dose-rate history. Time histories of dose rate are presented for EDA V and a Defense in Depth (DID) analysis base on EDA V. Additional details concerning the Enhanced Design Alternative II are provided in the 'LADS 3-12 Requests' interoffice correspondence (CRWMS M and O 1999a)

  17. Conduction Block of Peripheral Nerve Using High Frequency Alternating Currents Delivered through an Intrafascicular Electrode

    OpenAIRE

    Ackermann, D. Michael; Foldes, Emily L.; Bhadra, Niloy; Kilgore, Kevin L.

    2010-01-01

    Many diseases are characterized by undesired or pathological neural activity. The local delivery of high frequency currents has been shown to be an effective method for blocking neural conduction in peripheral nerves and may provide a therapy for these conditions. To date, all studies of high frequency conduction block have utilized extraneural (cuff) electrodes to achieve conduction block. In this study we show that high frequency conduction block is feasible using intrafascicular electrodes.

  18. Use of Biosensors as Alternatives to Current Regulatory Methods for Marine Biotoxins

    OpenAIRE

    Botana, Luis M.; M. Carmen Louzao; Natalia Vilariño; Fonfría, Eva S.

    2009-01-01

    Marine toxins are currently monitored by means of a bioassay that requires the use of many mice, which poses a technical and ethical problem in many countries. With the exception of domoic acid, there is a legal requirement for the presence of other toxins (yessotoxin, saxitoxin and analogs, okadaic acid and analogs, pectenotoxins and azaspiracids) in seafood to be controlled by bioassay, but other toxins, such as palytoxin, cyclic imines, ciguatera and tetrodotoxin are potentially present in...

  19. Hunger for iron: the alternative siderophore iron scavenging systems in highly virulent Yersinia.

    Directory of Open Access Journals (Sweden)

    Alexander eRakin

    2012-11-01

    Full Text Available Low molecular weight siderophores are used by many living organisms to scavenge scarcely available ferric iron. Presence of at least a single siderophore-based iron acquisition system is usually acknowledged as a virulence-associated trait and a prerequisite to become an efficient and successful pathogen. Currently it is assumed that yersiniabactin (Ybt is the solely functional endogenous siderophore iron uptake system in highly virulent Yersinia (Yersinia pestis, Y. pseudotuberculosis and Y. enterocolitica biotype 1B. Genes responsible for biosynthesis, transport and regulation of the yersiniabactin (ybt production are clustered on a mobile genetic element, the High Pathogenicity Island (HPI that is responsible for broad dissemination of the ybt genes in Enterobacteriaceae. However, the ybt gene cluster is absent from nearly half of Y. pseudotuberculosis O3 isolates and epidemic Y. pseudotuberculosis O1 isolates responsible for the Far East Scarlet-like Fever. Several potential siderophore-mediated iron uptake gene clusters are documented in Yersinia genomes, however neither of them have been proven to be functional. It has been suggested that at least two siderophores alternative to Ybt may operate in the highly virulent Yersinia pestis / Y. pseudotuberculosis group, and are referred to as pseudochelin (Pch and yersiniachelin (Ych. Furthermore, most sporadic Y. pseudotuberculosis O1 strains possess gene clusters encoding all three iron scavenging systems. Thus, the Ybt system appears not to be the sole endogenous siderophore iron uptake system in the highly virulent yersiniae and may be efficiently substituted and / or supplemented by alternative iron scavenging systems.

  20. Current major cancer targets for nanoparticle systems.

    Science.gov (United States)

    Wesselinova, Diana

    2011-02-01

    This review presents some common features of nanoparticles - activity, toxicity and biological activity. Humans are exposed to tiny particles via dust storms, volcanic ash, and other natural processes and the body systems are well adapted to protect from these potentially harmful intruders. Technological advancement has also changed the character of particulate pollution, increasing the proportion of nanometer-sized particles - "nanoparticles" and expanding the variety of chemical compositions. Studies have shown a strong correlation between particulate air pollution levels, respiratory and cardiovascular diseases, various cancers, and mortality. Adverse effects of nanoparticles on human health depend on individual factors such as genetics and existing disease, as well as exposure, and nanoparticle chemistry, size, shape, agglomeration state, and electromagnetic properties. The key to understand the toxicity of nanoparticles is their size, smaller than cells and cellular organelles, which allows them to penetrate these basic biological structures, disrupting their normal function. Examples of toxic effects include tissue inflammation, and altered cellular redox balance toward oxidation, causing abnormal function or cell death. Some of these materials have desirable characteristics for industrial applications, as nanostructured materials often exhibit beneficial properties, from UV absorbance in sunscreen to oil-less lubrication of motors. In the sense of the huge surrounding positive and negative influence of known and unknown NP-impacts it seems very important to understand and forecast the processes in the body, due to the interaction between these two sides - organism. How nanoparticles can be used as drug delivery systems and imaging devices to increase the efficacy per dose of therapeutic or imaging contrast agents; how nanoparticles will be further developed to improve their functionality in cancer treatment and imaging? How reacts the immune system of the

  1. Eddy Current System and Method for Crack Detection

    Science.gov (United States)

    Wincheski, Russell A. (Inventor); Simpson, John W. (Inventor)

    2012-01-01

    An eddy current system and method enables detection of sub-surface damage in a cylindrical object. The invention incorporates a dual frequency, orthogonally wound eddy current probe mounted on a stepper motor-controlled scanning system. The system is designed to inspect for outer surface damage from the interior of the cylindrical object.

  2. Financing alternatives and incentives for solar-thermal central-receiver systems

    Energy Technology Data Exchange (ETDEWEB)

    Bos, P.B.

    1982-07-01

    As a result of various recently enacted incentive and regulatory legislation combined with the new administration policy and budgetary guidelines, the commercialization of solar thermal central receiver systems will involve financing alternatives other than conventional utility financing. This study was conducted to identify these potential financing alternatives and the associated requirements and impacts on the Department of Energy program. Based upon this analysis, it is concluded that the current alternative financing window is extremely short (through 1985), and that an extension or at the least a gradual phasing out, of the solar tax credits is necessary for the successful transfer of the central receiver technology to the private sector. Furthermore, throughout this time period, continued government support of the R and D activities is necessary to provide the necessary confidence in this technology for the private (financial) sector to underwrite this technology transfer. Consequently, even though the central receiver technology shows high promise for replacing a significant fraction of the oil/gas-fired utility industry peaking and intermediate generation, the current readiness status of this technology still requires further direct and indirect government support for a successful technology transfer. The direct government research and development support will provide the basis for a technological readiness and confidence, whereas the indirect tax incentive support serves to underwrite the extraordinary risks associated with the technology transfer. These support requirements need only be limited to and decreasing during this technology transfer phase, since as the systems approach successful full-scale commercialization, the extraordinary risks will be gradually eliminated. At the time of commercialization the system's value should be on a par with the installed system's cost.

  3. Effects of alternating current imposition and alkaline earth elements on modification of primary Mg_2Si crystals in hypereutectic Mg-Si alloy

    Institute of Scientific and Technical Information of China (English)

    DU Jun; K. IWAI; LI Wen-fang; PENG Ji-hua

    2009-01-01

    The effects of alternating current imposition and/or alkaline earth elements on modification of the primary Mg_2Si crystals in the hypereutectic Mg-Si alloy were investigated. An alternating current of 60 A with frequency of 1 kHz was applied into the hypereutectic Mg-Si melt which was alloyed with alkaline earth elements or not in the fixed temperature range from 700 to 630 ℃. The results show that the primary Mg_2Si crystals could be refined by imposing alternating current or adding alkaline elements. Compared with the samples treated by adding 0.4% Ca or 0.4% Sr, higher modification efficiency could be obtained for the samples treated by imposing alternating current. No further modification efficiency could be obtained for the samples treated by imposing alternating current combined with 0.4% Ca or 0.4% Sr addition.

  4. Current status of nephrogenic systemic fibrosis

    International Nuclear Information System (INIS)

    Nephrogenic systemic fibrosis (NSF) occurs in patients with advanced chronic kidney disease (CKD) or acute renal failure, most commonly following exposure to gadolinium-based contrast agents (GBCAs). NSF can be debilitating and associated with increased mortality. The putative association of NSF with GBCAs prompted the development of guidelines to limit the use of these contrast agents in at-risk patients. Indeed, the incidence of NSF has decreased dramatically following application of these guidelines, which appears to be the only effective means of decreasing NSF incidence. Thus, increasing clinician awareness of these updated guidelines is important. The present review introduces and compares updated guidelines for GBCA use and discusses the latest advances in the understanding of the pathogenic mechanisms and treatment of NSF

  5. Internal heating of lithium-ion batteries using alternating current based on the heat generation model in frequency domain

    Science.gov (United States)

    Zhang, Jianbo; Ge, Hao; Li, Zhe; Ding, Zhanming

    2015-01-01

    This study develops a method to internally preheat lithium-ion batteries at low temperatures with sinusoidal alternating current (AC). A heat generation rate model in frequency domain is developed based on the equivalent electrical circuit. Using this model as the source term, a lumped energy conservation model is adopted to predict the temperature rise. These models are validated against the experimental results of preheating an 18650 cell at different thermal insulation conditions. The effects of current amplitude and frequency on the heating rate are illustrated with a series of simulated contours of heating time. These contours indicate that the heating rate increases with higher amplitude, lower frequency and better thermal insulation. The cell subjected to an alternating current with an amplitude of 7 A (2.25 C) and a frequency of 1 Hz, under a calibrated heat transfer coefficient of 15.9 W m-2 K-1, can be heated from -20 °C to 5 °C within 15 min and the temperature distribution remains essentially uniform. No capacity loss is found after repeated AC preheating tests, indicating this method incurs little damage to the battery health. These models are computationally-efficient and can be used in real time to control the preheating devices in electric vehicles.

  6. System for verification in situ of current transformers in high voltage substations; Sistema para verificacao in situ de transformadores de corrente em substacoes de alta tensao

    Energy Technology Data Exchange (ETDEWEB)

    Mendonca, Pedro Henrique; Costa, Marcelo M. da; Dahlke, Diogo B.; Ikeda, Minoru [LACTEC - Instituto de Tecnologia para o Desenvolvimento, Curitiba, PR (Brazil)], Emails: pedro.henrique@lactec.org.br, arinos@lactec.org.br, diogo@lactec.org.br, minoru@lactec.org.br, Celso.melo@copel.com; Carvalho, Joao Claudio D. de [ELETRONORTE, Belem, PR (Brazil)], E-mail: marcelo.melo@eln.gov.br; Teixeira Junior, Jose Arinos [ELETROSUL, Florianopolis, SC (Brazil)], E-mail: jclaudio@eletrosul.gov.br; Melo, Celso F. [Companhia Paranaense de Energia (COPEL), Curitiba, PR (Brazil)], E-mail: Celso.melo@copel.com

    2009-07-01

    This work presents an alternative proposal to the execute the calibration of conventional current transformer at the field, using a verification system composed by a optical current transformer as a reference standard, able to installation in extra high voltage bars.

  7. A superconducting transformer system for high current cable testing.

    Science.gov (United States)

    Godeke, A; Dietderich, D R; Joseph, J M; Lizarazo, J; Prestemon, S O; Miller, G; Weijers, H W

    2010-03-01

    This article describes the development of a direct-current (dc) superconducting transformer system for the high current test of superconducting cables. The transformer consists of a core-free 10,464 turn primary solenoid which is enclosed by a 6.5 turn secondary. The transformer is designed to deliver a 50 kA dc secondary current at a dc primary current of about 50 A. The secondary current is measured inductively using two toroidal-wound Rogowski coils. The Rogowski coil signal is digitally integrated, resulting in a voltage signal that is proportional to the secondary current. This voltage signal is used to control the secondary current using a feedback loop which automatically compensates for resistive losses in the splices to the superconducting cable samples that are connected to the secondary. The system has been commissioned up to 28 kA secondary current. The reproducibility in the secondary current measurement is better than 0.05% for the relevant current range up to 25 kA. The drift in the secondary current, which results from drift in the digital integrator, is estimated to be below 0.5 A/min. The system's performance is further demonstrated through a voltage-current measurement on a superconducting cable sample at 11 T background magnetic field. The superconducting transformer system enables fast, high resolution, economic, and safe tests of the critical current of superconducting cable samples. PMID:20370213

  8. A Superconducting transformer system for high current cable testing

    Energy Technology Data Exchange (ETDEWEB)

    Godeke, A.; Dietderich, D. R.; Joseph, J. M.; Lizarazo, J.; Prestemon, S. O.; Miller, G.; Weijers, H. W.

    2010-02-15

    This article describes the development of a direct-current (dc) superconducting transformer system for the high current test of superconducting cables. The transformer consists of a core-free 10 464 turn primary solenoid which is enclosed by a 6.5 turn secondary. The transformer is designed to deliver a 50 kA dc secondary current at a dc primary current of about 50 A. The secondary current is measured inductively using two toroidal-wound Rogowski coils. The Rogowski coil signal is digitally integrated, resulting in a voltage signal that is proportional to the secondary current. This voltage signal is used to control the secondary current using a feedback loop which automatically compensates for resistive losses in the splices to the superconducting cable samples that are connected to the secondary. The system has been commissioned up to 28 kA secondary current. The reproducibility in the secondary current measurement is better than 0.05% for the relevant current range up to 25 kA. The drift in the secondary current, which results from drift in the digital integrator, is estimated to be below 0.5 A/min. The system's performance is further demonstrated through a voltage-current measurement on a superconducting cable sample at 11 T background magnetic field. The superconducting transformer system enables fast, high resolution, economic, and safe tests of the critical current of superconducting cable samples.

  9. Palm oil production in Peruvian Amazon Basin. A case study of current effects and emerging localized alternatives in Loreto district

    OpenAIRE

    Jensen, Charlotte Bratberget

    2015-01-01

    An analysis of palm oil production in the Peruvian Amazon basin was carried out in a systemic way, as part of a whole, with its complexities. With an agroecological perspective, the social, ecological and economic effects of this production are discussed. Additionally, alternatives that could better fulfil the necessities of farmers were explored. The oil palm, Elaeis guineensis, originally from West Africa, is a common plant in an enormous industry that is extensive in South East Asia, ma...

  10. One shots and alternatives in synchronous digital system design

    International Nuclear Information System (INIS)

    Undesirable features of nonostable multivibrators (one shots) in digital integrated circuits are described and some alternatives to their use are discussed. These include flip-flops and gates, delay lines, and other methods

  11. ALTERNATIVE SYSTEM OF MEDICINE IN INDIA: A REVIEW

    OpenAIRE

    Memon Shakeel; Pathan Dilnawaz; Ziyaurrrahman; Kamal Safura; Bora Chanderprakash

    2011-01-01

    Alternative Medicine is a term commonly used to include all the healing practice "that does not fall within the realm of conventional medicine". It can be defined as "a variety of therapeutic or preventive health care practices, such as homeopathy, naturopathy, chiropractic, and herbal medicine that do not follow generally accepted medical methods and may not have a scientific explanation for their effectiveness.” Complementary and alternative medicine (CAM) is the term for medical products a...

  12. Citizenship and Consumption: Mobilisation in Alternative Food Systems in France

    OpenAIRE

    Dubuisson-Quellier, Sophie; Lamine, Claire; Le Velly, Ronan

    2011-01-01

    Contemporary alternative food movement implement various means of action, which were previously developed by movements that were striving to construct citizenship through consumption. Drawing on the results of in-depth ethnographic studies, this article analyses the main fields of action of three French organisations: consumer edu¬cation, implementation of alternative forms of trade and consumer mobilisation in protest campaigns. It shows that these actions require the movement to build repres...

  13. Potential alternatives to edible oils for biodiesel production - A review of current work

    International Nuclear Information System (INIS)

    Biodiesel production is a very modern and technological area for researchers due to the relevance that it is winning everyday because of the increase in the petroleum price and the environmental advantages. Currently, biodiesel is mainly prepared from conventionally grown edible oils such as rapeseed, soybean, sunflower and palm thus leading to alleviate food versus fuel issue. About 7% of global vegetable oil supplies were used for biodiesel production in 2007. Extensive use of edible oils may cause other significant problems such as starvation in developing countries. The use of non-edible plant oils when compared with edible oils is very significant in developing countries because of the tremendous demand for edible oils as food, and they are far too expensive to be used as fuel at present. The production of biodiesel from different non-edible oilseed crops has been extensively investigated over the last few years.

  14. Potential alternatives to edible oils for biodiesel production - A review of current work

    International Nuclear Information System (INIS)

    Biodiesel production is a very modern and technological area for researchers due to the relevance that it is winning everyday because of the increase in the petroleum price and the environmental advantages. Currently, biodiesel is mainly prepared from conventionally grown edible oils such as rapeseed, soybean, sunflower and palm thus leading to alleviate food versus fuel issue. About 7% of global vegetable oil supplies were used for biodiesel production in 2007. Extensive use of edible oils may cause other significant problems such as starvation in developing countries. The use of non-edible plant oils when compared with edible oils is very significant in developing countries because of the tremendous demand for edible oils as food, and they are far too expensive to be used as fuel at present. The production of biodiesel from different non-edible oilseed crops has been extensively investigated over the last few years. (author)

  15. Including Alternative Resources in State Renewable Portfolio Standards: Current Design and Implementation Experience

    Energy Technology Data Exchange (ETDEWEB)

    Heeter, J.; Bird, L.

    2012-11-01

    Currently, 29 states, the District of Columbia, and Puerto Rico have instituted a renewable portfolio standard (RPS). An RPS sets a minimum threshold for how much renewable energy must be generated in a given year. Each state policy is unique, varying in percentage targets, timetables, and eligible resources. This paper examines state experience with implementing renewable portfolio standards that include energy efficiency, thermal resources, and non-renewable energy and explores compliance experience, costs, and how states evaluate, measure, and verify energy efficiency and convert thermal energy. It aims to gain insights from the experience of states for possible federal clean energy policy as well as to share experience and lessons for state RPS implementation.

  16. Investigation of alternate power source for Space Shuttle Orbiter hydraulic system

    Science.gov (United States)

    Simon, William E.; Young, Fred M.

    1993-05-01

    This investigation consists of a short-term feasibility study to determine whether or not an alternate electrical power source would trade favorably from a performance, reliability, safety, operation, and weight standpoint in replacing the current auxiliary power unit subsystems with its attendant components (water spray boiler, hydrazine fuel and tanks, feed and vent lines, controls, etc.), operating under current flight rules. Results of this feasibility study are used to develop recommendations for the next step (e.g., to determine if such an alternate electrical power source would show an advantage given that the current operational flight mode of the system could be modified in such a way as not to constrain the operational capability and safety of the vehicle). However, this next step is not within the scope of this investigation. This study does not include a cost analysis, nor does it include investigation of the integration aspects involved in such a trade, except in a qualitative sense for the determination of concept feasibility.

  17. Equivalency assessment for an eddy current system used for steam generator tubing inspection

    International Nuclear Information System (INIS)

    Eddy current testing is widely used for inspecting steam generator tubing in nuclear power plants (NPPs). The inspection technique for steam generator tubing in NPPs should be qualified in accordance with examination guidelines. When the components of a qualified system such as eddy current tester, probe, and data analysis program, are changed, the equivalency of the modified system to the originally qualified system must be verified. The eddy current tester is the most important part of an eddy current testing system because it excites and transmits alternating currents to the probe, receives coil impedance of the probe and generates signals for anomalies. The Korea Hydro and Nuclear Power Co., Ltd. (KHNP) developed an eddy current testing system with an eddy current tester and data acquisition-analysis program for inspecting the steam generator tubing in NPPs; this system can be used for an array probe and as a bobbin and rotating probes. The equivalency assessment for the currently developed system was carried out, and we describe the results in this paper

  18. Equivalency assessment for an eddy current system used for steam generator tubing inspection

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Chan Hee; Lee, Tae Hun; Yoo, Hyun Ju; Moon, Gyoon Young [Korea Hydro and Nuclear Power Company Ltd., Central Research Institute, Daejeon (Korea, Republic of)

    2015-08-15

    Eddy current testing is widely used for inspecting steam generator tubing in nuclear power plants (NPPs). The inspection technique for steam generator tubing in NPPs should be qualified in accordance with examination guidelines. When the components of a qualified system such as eddy current tester, probe, and data analysis program, are changed, the equivalency of the modified system to the originally qualified system must be verified. The eddy current tester is the most important part of an eddy current testing system because it excites and transmits alternating currents to the probe, receives coil impedance of the probe and generates signals for anomalies. The Korea Hydro and Nuclear Power Co., Ltd. (KHNP) developed an eddy current testing system with an eddy current tester and data acquisition-analysis program for inspecting the steam generator tubing in NPPs; this system can be used for an array probe and as a bobbin and rotating probes. The equivalency assessment for the currently developed system was carried out, and we describe the results in this paper.

  19. Alternating-current measurements in scanning electrochemical microscopy, part 1: principle and theory.

    Science.gov (United States)

    Trinh, Dao; Keddam, Michel; Novoa, Xosé R; Vivier, Vincent

    2011-08-01

    The development of the scanning electrochemical microscope in ac mode is presented from both experimental and theoretical point of views. The experiments are performed with the ferri/ferrocyanide redox mediator as model system. Based on analysis of the frequency-dependent collection efficiency, diffusion between the probe and the substrate is investigated, and analysis of time constants allows evaluation of the size of the sensing area under investigation. The experimental results are in good agreement with numerical simulations. PMID:21633998

  20. A high-Tc superconducting quantum interference device with an alternating current bias DOIT and additional positive feedback

    International Nuclear Information System (INIS)

    This study shows that the alternating current (AC) bias direct offset integrated technique (DOIT) reduces low-frequency noise without increasing the level of white noise in a high-Tc DC superconducting quantum interference device (SQUID). Additional positive feedback (APF), which can improve the effective flux-to-voltage transfer function, it used to reduce the equivalent flux noise due to the voltage noise of the preamplifier of the magnetometer. The use of APF combined with the AC bias DOIT reduced the noise of the magnetometer by factors of 1.5 at 100 Hz, 3.5 at 10 Hz, and 5.3 at 1 Hz when compared with noise levels obtained with the static current bias DOIT. (author)

  1. The Comparison of Selected Alternative Schools' Pedagogical Systems with the Don Bosco Preventive System

    OpenAIRE

    LAŇKA, Jiří

    2008-01-01

    The Paper discusses the education and upbringing as a system, and is especially aimed at the Preventive system of Saint John Bosco. The Bosco{\\crq}s system is then compared to the selected alternative schools{\\crq} pedagogical systems, which take humanism as the core of approach to the child{\\crq}s soul. The aim of this baccalaureate paper is to compare the selected issues, which the author sees as being important. It is the specification of target group, to which the pedagogical system is ai...

  2. Silver eel migration, wind power and alternating current fields; Blankaalsvandring, vindkraft och vaexelstroemsfaelt, 2011

    Energy Technology Data Exchange (ETDEWEB)

    Lagenfelt, Ingvar; Andersson, Ingemar; Westerberg, Haakan

    2012-02-15

    How are eels affected by large offshore wind farms? The study follows the silver eels' migration and behavior at Lillgrund wind farm in Oeresund and the passage over an 130 kV AC cable between the mainland and Oeland. The aim is to see if the AC cable precludes or otherwise affects the eel's ability to reach its destination. Eels migrate up to 7500 km from the Baltic Sea to spawn in the Sargasso Sea. Every delay is of importance for the silver eels, which must be able to travel the entire distance on a single energy reserve. Fish, which make use of the earth's magnetic field for navigation or which are sensitive to electromagnetic fields, may be affected by AC cables on the seabed. The study shows that the silver eels swimming speed was reduced when there was more current in the cable and there was an average delay of 40 minutes before they passed it

  3. The effects of ultrasound and alternating current on the laser penetration in the tissue.

    Science.gov (United States)

    Dawood, Munqith Saleem

    2016-07-01

    The visible (VIS) and near-infrared (NIR) lasers are now widely used in therapeutic and other medical applications. Some of these applications require to deliver the laser energy deep toward the desired tissue target or organ. The aim of this in vitro study is to investigate practically whether the modulation of laser energy by employing the therapeutic ultrasound or electrical energies can increase the penetration depth of the laser light inside the tissue. Such modulation was implemented in this study by coupling the (c.w.) diode and Nd:YAG laser energies with the ultrasound or AC current simultaneously as they pass through preprepared ex vivo bovine muscular tissue strips. Two wavelengths of diode lasers were used, 637 and 808 nm beside the 1064-nm Nd:YAG laser. The results showed a noticeable decrease of these laser attenuation factors as they pass through the tissue strips in the presence of the ultrasound or AC energies. By using this coupling modulation, the capability of increasing the laser penetration depths inside the tissue was confirmed without having to increase their applied power. PMID:27098338

  4. A Study on Measurement Error during Alternating Current Induced Voltage Tests on Large Transformers

    Institute of Scientific and Technical Information of China (English)

    WANG Xuan; LI Yun-ge; CAO Xiao-long; LIU Ying

    2006-01-01

    The large transformer is pivotal equipment in an electric power supply system; Its partial discharge test and the induced voltage withstand test on large transformers are carried out at a frequency about twice the working frequency. If the magnetizing inductance cannot compensate for the stray capacitance, the test sample turns into a capacitive load and a capacitive rise exhibits in the testing circuit. For self-restoring insulation, a method has been recommended in IEC60-1 that an unapproved measuring system be calibrated by an approved system at a voltage not less than 50% of the rated testing voltage, and the result then be extrapolated linearly. It has been found that this method leads to great error due to the capacitive rise if it is not correctly used during a withstand voltage test under certain testing conditions, especially for a test on high voltage transformers with large capacity. Since the withstand voltage test is the most important means to examine the operation reliability of a transformer, and it can be destructive to the insulation, a precise measurement must be guaranteed. In this paper a factor, named as the capacitive rise factor, is introduced to assess the rise. The voltage measurement error during the calibration is determined by the parameters of the test sample and the testing facilities, as well as the measuring point. Based on theoretical analysis in this paper, a novel method is suggested and demonstrated to estimate the error by using the capacitive rise factor and other known parameters of the testing circuit.

  5. Nuclear proliferation and civilian nuclear power: report of the Nonproliferation Alternative Systems Assessment Program. Executive summary

    International Nuclear Information System (INIS)

    The Nonproliferation Alternative Systems Assessment Program (NASAP) assessed alternative nuclear systems to find those with the lowest proliferation risk. The findings of the NASAP studies are: current and future nuclear-power systems can be made more proliferation-resistant. As long as doubts about security and fuel supply remain, more resource-efficient (and potentially less proliferation-resistant) systems will be attractive to some nations. Under some scenarios, domestic uranium supply/demand imbalances are possible beyond the year 2010. The worldwide uranium supply/demand balance is even less certain than the domestic picture. Other nuclear resources are less of a problem than uranium. Doubts about fuel supply can be alleviated in several ways. The approaches available to provide security of supply fall into three categories: resource extenders; supply improvements; and institutional and technical measures. Resource extension options include improvements to once-through cycles, advanced converters, recycle, and breeder reactors. The most promising resource extension options are light water reactor improvements (including reduced enrichment tails assay) and continued development of the plutonium-fueled breeder reactors. Uranium-supply initiatives include measures to reduce uncertainty in the estimated size of the resource base, to exploit it efficiently, and to ensure equitable access. An international nonproliferation regime will require institutional measures and technical approaches

  6. Rapid architecture alternative modeling (RAAM): A framework for capability-based analysis of system of systems architectures

    Science.gov (United States)

    Iacobucci, Joseph V.

    The research objective for this manuscript is to develop a Rapid Architecture Alternative Modeling (RAAM) methodology to enable traceable Pre-Milestone A decision making during the conceptual phase of design of a system of systems. Rather than following current trends that place an emphasis on adding more analysis which tends to increase the complexity of the decision making problem, RAAM improves on current methods by reducing both runtime and model creation complexity. RAAM draws upon principles from computer science, system architecting, and domain specific languages to enable the automatic generation and evaluation of architecture alternatives. For example, both mission dependent and mission independent metrics are considered. Mission dependent metrics are determined by the performance of systems accomplishing a task, such as Probability of Success. In contrast, mission independent metrics, such as acquisition cost, are solely determined and influenced by the other systems in the portfolio. RAAM also leverages advances in parallel computing to significantly reduce runtime by defining executable models that are readily amendable to parallelization. This allows the use of cloud computing infrastructures such as Amazon's Elastic Compute Cloud and the PASTEC cluster operated by the Georgia Institute of Technology Research Institute (GTRI). Also, the amount of data that can be generated when fully exploring the design space can quickly exceed the typical capacity of computational resources at the analyst's disposal. To counter this, specific algorithms and techniques are employed. Streaming algorithms and recursive architecture alternative evaluation algorithms are used that reduce computer memory requirements. Lastly, a domain specific language is created to provide a reduction in the computational time of executing the system of systems models. A domain specific language is a small, usually declarative language that offers expressive power focused on a particular

  7. Alternatives generation and analysis for phase I intermediate waste feed staging system design requirements

    Energy Technology Data Exchange (ETDEWEB)

    Britton, M.D.

    1996-10-02

    This document provides; a decision analysis summary; problem statement; constraints, requirements, and assumptions; decision criteria; intermediate waste feed staging system options and alternatives generation and screening; intermediate waste feed staging system design concepts; intermediate waste feed staging system alternative evaluation and analysis; and open issues and actions.

  8. Emission current control system for multiple hollow cathode devices

    Science.gov (United States)

    Beattie, John R. (Inventor); Hancock, Donald J. (Inventor)

    1988-01-01

    An emission current control system for balancing the individual emission currents from an array of hollow cathodes has current sensors for determining the current drawn by each cathode from a power supply. Each current sensor has an output signal which has a magnitude proportional to the current. The current sensor output signals are averaged, the average value so obtained being applied to a respective controller for controlling the flow of an ion source material through each cathode. Also applied to each controller are the respective sensor output signals for each cathode and a common reference signal. The flow of source material through each hollow cathode is thereby made proportional to the current drawn by that cathode, the average current drawn by all of the cathodes, and the reference signal. Thus, the emission current of each cathode is controlled such that each is made substantially equal to the emission current of each of the other cathodes. When utilized as a component of a multiple hollow cathode ion propulsion motor, the emission current control system of the invention provides for balancing the thrust of the motor about the thrust axis and also for preventing premature failure of a hollow cathode source due to operation above a maximum rated emission current.

  9. Tests of an alternating current propulsion subsystem for electric vehicles on a road load simulator

    Science.gov (United States)

    Stenger, F. J.

    1982-01-01

    The test results of a breadboard version of an ac electric-vehicle propulsion subsystem are presented. The breadboard was installed in the NASA Lewis Research Center Road Load Simulator facility and tested under steady-state and transient conditions. Steady-state tests were run to characterize the system and component efficiencies over the complete speed-torque range within the capability of the propulsion subsystem in the motoring mode of operation. Transient tests were performed to determine the energy consumption of the breadboard over the acceleration and cruise portions of SAE J227 and driving schedules B, C, and D. Tests in the regenerative mode were limited to the low-gear-speed range of the two speed transaxle used in the subsystem. The maximum steady-state subsystem efficiency observed for the breadboard was 81.5 percent in the high-gear-speed range in the motoring mode, and 76 percent in the regenerative braking mode (low gear). The subsystem energy efficiency during the transient tests ranged from 49.2 percent for schedule B to 68.4 percent for Schedule D.

  10. Electro-optically responsive composites of gold nanospheres in 5CB liquid crystal under direct current and alternating current joint action

    Energy Technology Data Exchange (ETDEWEB)

    Hadjichristov, Georgi B.; Marinov, Yordan G.; Petrov, Alexander G. [Institute of Solid State Physics, Bulgarian Academy of Sciences, Sofia 1784 (Bulgaria); Bruno, Emanuela [Dipartimento di Fisica, Università della Calabria, Via Pietro Bucci, Cubo 31C, 87036 Rende (CS) (Italy); Marino, Lucia, E-mail: lucia.marino@fis.unical.it [CNR-IPCF UoS di Cosenza, Licryl Laboratory, and Centro di Eccellenza CEMIF.CAL, Università della Calabria, 87036 Rende (CS) (Italy); Scaramuzza, Nicola [Dipartimento di Fisica, Università della Calabria, Via Pietro Bucci, Cubo 31C, 87036 Rende (CS) (Italy); CNR-IPCF UoS di Cosenza, Licryl Laboratory, and Centro di Eccellenza CEMIF.CAL, Università della Calabria, 87036 Rende (CS) (Italy)

    2014-02-28

    Direct current (DC) electro-optical (EO) control of transmitted laser beam intensity based on EO controlled coherent light scattering and diffraction by stationary longitudinal texture pattern (LTP) is achieved in planar-oriented cells with a composite mixture of polymer-coated gold spherical nanoparticles (Au-NPs) with a mean diameter of about 12 nm and the room-temperature nematic pentylcyanobiphenyl (5CB). At relatively low DC voltage of about 5 V, the effective scattering/diffraction by Au-NPs/5CB composites leads to a spatial spreading of transmitted coherent light from a low-power continuous wave laser beam, resulting in a drastic reduction of its local intensity. The effect is polarization dependent and is strongest when the polarization of the input laser beam is along the LTP. The EO response of Au-NPs/5CB mixtures is studied under DC and alternating current (AC) joint action with the aim of the potential use of these composite materials as EO controlled diffusers. The specific V-shaped sharp dip in the DC voltage-dependent coherent light transmittance of Au-NPs/5CB planar films, as well as the possibility for erasing the scattering/diffractive LTP in the films by joint low AC voltage, can be useful for EO applications in the field of process control and for detection of weak dynamic electric fields.

  11. Control strategy minimizing the converter-alternating current motor losses: application to electric traction; Strategies de commande minimisant les pertes d'un ensemble convertisseur - machine alternative: application a la traction electrique

    Energy Technology Data Exchange (ETDEWEB)

    Bastiani, Ph.

    2001-02-01

    Improving the efficiency of the converter-alternating current motor system is a major task in electric traction. Global energy optimisation implies a specific approach at system scale. To reach this goal, we have chosen an algebraic method using sub-system models. To start with, a synchronous machine Park model is developed to take account magnetic saturation and iron losses. Then, an averaged model of the voltage inverter is used in order to obtain a simplified model of the losses to be implemented in our optimisation method. This is how the global model is built including losses in the synchronous machine along with the losses of the power converter. Experimental results are there to validate our approach. This study proposes a method based on algebraic formulation of the general laws to control torque. Algorithms take into account magnetic circuits saturation and power losses in both the machine and its converter. Here again, experimental results validate the algorithm on several test benches. Achieved efficiency improvement is important compared to existing usual control strategies. The proposed method can be generalised to other machine-converter systems. As a matter of fact we have extended our study to the induction machine. As a complement ti this study we have looked at the effects natural limitations of voltages and currents in the torque-speed plane. Therefore algebraic formulation of the torque-speed plane and optimisation strategies are proposed including those constraints. (author)

  12. Alternative Design Concepts for Multi-Circuit HTS Link Systems

    CERN Document Server

    Ballarino, A

    2011-01-01

    Superconducting cables for power transmission usually contain two conductors for DC application, or three conductors for AC, with high voltage insulation. In contrast, for some applications related to accelerators it is convenient to transfer high currents via superconducting links feeding a number of circuits at relatively low voltage, of the order of a kilovolt, over distances of up to a few hundred meters. For power transmission applications based on cooling via sub-cooled liquid nitrogen, suitable HTS conductors are only available in the form of tape, and a multi-layer variant can be envisaged for the multi-circuit links. However, where cooling to temperatures of the order of 20 K is feasible, MgB2 conductor, available in the form of both tape and wire, can also be envisaged and in the latter case used to assemble round cables. There are, therefore, two distinct topologies - based on the use of wires or tapes - that can be envisaged for use in applications to multi-circuit link systems. In this paper the ...

  13. Sizing Performance of the Newly Developed Eddy Current System

    International Nuclear Information System (INIS)

    This paper describes the comparison results of sizing performance for two systems. The KHNP developed a new eddy current testing system for the inspection of steam generator tubing in domestic nuclear power plants. The equivalency assessment of the newly developed system with the EPRI-qualified system was already carried out. In this paper, the comparisons of depth-sizing performance for the artificial flaws between two systems were performed. The results show that the newly developed system is in good agreement with the qualified system. Therefore, it is expected that the newly developed eddy current system can be used for the inspection of steam generator tubing in nuclear power plants. There are some non-destructive examination (NDE) methods for the inspection of components in nuclear power plants, such as ultrasonic, radiographic, eddy current testing, etc. The eddy current testing is widely used for the inspection of steam generator (SG) tubing because it offers a relatively low cost approach for high speed, large scale testing of metallic materials in high pressure and temperature engineering systems. The Korea Hydro and Nuclear Power Co., Ltd. (KHNP) developed an eddy current testing system for the inspection of steam generator tubing in nuclear power plants. This system includes not only hardware but software such as the frequency generator and data acquisition-analysis program. The foreign eddy current system developed by ZETEC is currently used for the inspection of steam generator tubing in domestic nuclear power plants. The equivalency assessment between two systems was already carried out in accordance with the EPRI steam generator examination guidelines

  14. SAGE SOLVENT ALTERNATIVES GUIDE: SYSTEM IMPROVEMENTS FOR SELECTING INDUSTRIAL SURFACE CLEANING ALTERNATIVES

    Science.gov (United States)

    The paper describes computer software, called SAGE, that can provide not only cleaning recommendations but also general information on various surface cleaning options. In short, it is an advisory system which can provide users with vital information on the cleaning process optio...

  15. Alternating-Current InGaN/GaN Tunnel Junction Nanowire White-Light Emitting Diodes.

    Science.gov (United States)

    Sadaf, S M; Ra, Y-H; Nguyen, H P T; Djavid, M; Mi, Z

    2015-10-14

    The current LED lighting technology relies on the use of a driver to convert alternating current (AC) to low-voltage direct current (DC) power, a resistive p-GaN contact layer to inject positive charge carriers (holes) for blue light emission, and rare-earth doped phosphors to down-convert blue photons into green/red light, which have been identified as some of the major factors limiting the device efficiency, light quality, and cost. Here, we show that multiple-active region phosphor-free InGaN nanowire white LEDs connected through a polarization engineered tunnel junction can fundamentally address the afore-described challenges. Such a p-GaN contact-free LED offers the benefit of carrier regeneration, leading to enhanced light intensity and reduced efficiency droop. Moreover, through the monolithic integration of p-GaN up and p-GaN down nanowire LED structures on the same substrate, we have demonstrated, for the first time, AC operated LEDs on a Si platform, which can operate efficiently in both polarities (positive and negative) of applied voltage. PMID:26384135

  16. Justice dispensation through the alternative dispute resolution system in India

    OpenAIRE

    Krishna Agrawal

    2014-01-01

    The Law Commission of India in its 222nd report emphasized the need for Alternative Disputes Resolution (ADR) for the dispensation of justice, because the courts are inaccessible owing to various factors, e.g., poverty, social and political backwardness, illiteracy, ignorance, procedural formalities and inordinate delay in judgments. During the ancient period the disputes were resolved in an informal manner by neutral third persons or people’s court in villages and it continued till the middl...

  17. ALTERNATIVE FLUID MILK PROCUREMENT SYSTEMS FOR FLORIDA DAIRY FARMERS

    OpenAIRE

    Nubern, Christopher A.; Kilmer, Richard L.

    1995-01-01

    This article evaluates the effects of alternative fluid milk procurement strategies on the aggregate net revenue of Florida cooperative members. They are (1) supplemental milk obtained from import sources, (2) supplemental milk obtained from a supply plant, (3) increased supply as a result of an expanded production area, and (4) supplemental milk obtained through pooling arrangements with regional dairy cooperatives. The final ranking of a scenario appears to be dependent primarily on the tot...

  18. Optimization of cogeneration systems under alternative performance criteria

    International Nuclear Information System (INIS)

    In this study, a performance analysis based on alternative performance criteria has been performed for a reversible Carnot cycle, modified for cogeneration, with external irreversibilities. The optimum values of the design parameters of the cogeneration cycle were determined for different criteria. In this context, the effects of design parameters on the exergetic performance are investigated, and the results are discussed. The obtained results may guide towards a more realistic criterion for actual cogeneration plants

  19. A decision support system for regional hazardous waste management alternatives

    OpenAIRE

    Amouzegar, Mahyar A.; Jacobsen, Stephen E.

    1998-01-01

    With the passage of the Resource Conservation and Recovery Act (RCRA), and the subsequent amendments to RCRA, efforts to provide tighter controls on the transportation and disposal of hazardous waste have been steadily gaining ground. This paper, intended as a decision support tool for regional planning, incorporates information on the hazardous waste generation, treatment capacity and the costs of waste treatment alternatives into an optimization problem of finding the relationship between g...

  20. Revisiting Bourdieu: Alternative Educational Systems in the Light of the Theory of Social and Cultural Reproduction

    Science.gov (United States)

    Azaola, Marta Cristina

    2012-01-01

    The paper reflects upon the principles and practice of an alternative educational system operating in rural Mexico in the light of Bourdieu's theory of cultural and social reproduction. Bourdieu's theory seeks to explain processes of reproduction of power relations within schools and society; whereas alternative educational systems seek to expand…

  1. PECULIARITIES OF THE RISK MANAGEMENT SYSTEM ORGANIZATION IN CURRENT CONDITIONS

    OpenAIRE

    MIKHIN P.O.

    2014-01-01

    Risk-management system organization problem is topical nowadays. The innovation activity is defined as an activity vulnerable to risk and needs more attention. The basic approaches and elements of organization structure development in risk-management system are considered to find out the best structure for business modelling usage. Balance and combination of risk-management system types are required in current conditions.

  2. Signature of cluster disruption within magnetic fluid samples: The key information provided by low frequency alternating current susceptibility measurements

    Science.gov (United States)

    Du, Zhongzhou; Liu, Wenzhong; Zhong, Jing; Zhou, Ming; Zhang, Pu; Cesar Morais, Paulo

    2014-05-01

    This paper is focused on the signature of thermal-assisted cluster disruption while analyzing the inverse alternating current (AC) susceptibility (1/χ) versus temperature (T) curves recorded at lower AC frequencies (f), below 300 Hz. A commercial oil-based magnetic fluid (MF) sample was used in the experiments to investigate the critical temperature (T*) that characterizes the thermal disruption of aggregates suspended within the MF sample. T* was found to reduce as f increased within the frequency range of our investigation (63-263 Hz). Furthermore, T* was found to scale with the square of the applied AC frequency. Both theoretical and experimental evidences support that the excitation field frequency (f) dependence of the critical temperature (T*) is well described by T*(f)=T*(0)-Af/21+Bf2. The model is based on energy absorption of magnetic nanoparticles in an AC magnetic field.

  3. Elicitors as alternative strategy to pesticides in grapevine? Current knowledge on their mode of action from controlled conditions to vineyard.

    Science.gov (United States)

    Delaunois, Bertrand; Farace, Giovanni; Jeandet, Philippe; Clément, Christophe; Baillieul, Fabienne; Dorey, Stéphan; Cordelier, Sylvain

    2014-04-01

    Development and optimisation of alternative strategies to reduce the use of classic chemical inputs for protection against diseases in vineyard is becoming a necessity. Among these strategies, one of the most promising consists in the stimulation and/or potentiation of the grapevine defence responses by the means of elicitors. Elicitors are highly diverse molecules both in nature and origins. This review aims at providing an overview of the current knowledge on these molecules and will highlight their potential efficacy from the laboratory in controlled conditions to vineyards. Recent findings and concepts (especially on plant innate immunity) and the new terminology (microbe-associated molecular patterns, effectors, etc.) are also discussed in this context. Other objectives of this review are to highlight the difficulty of transferring elicitors use and results from the controlled conditions to the vineyard, to determine their practical and effective use in viticulture and to propose ideas for improving their efficacy in non-controlled conditions. PMID:23719689

  4. A new laser direct etching method of indium tin oxide electrode for application to alternative current plasma display panel

    International Nuclear Information System (INIS)

    For cost effective fabrication and time of alternative current plasma display panels (AC PDPs), an indium tin oxide (ITO) layer was patterned directly with a Q-switched diode pumped Nd:YVO4 laser (λ = 1064 nm). As experimental results, 500 mm/s scan speed with 40 kHz repetition rate was suitable for the application to AC PDP ITO electrode. In comparison with the chemically wet-etched ITO patterns by photolithography method, laser-ablated ITO patterns showed the formation of shoulders at the edge of the ITO lines and a ripple-like structure of the etched bottom. By dipping the laser-ablated ITO films in the chemical etching solution for 30 s at 50 deg. C, the shoulders were effectively removed without affecting the discharging properties of AC PDP.

  5. A reference current source for the calibration of current measuring systems in dosimetry using ionisation chambers

    International Nuclear Information System (INIS)

    This work describes a newly developed, easily handled current source containing one 90Sr + 90Y Y beta emitter. Four different currents from 7x10-11A to 4x10-14A are supplied. From 5 to 10 control measurements were performed for each of the four currents during a period of eight months. The standard deviation of the values of these control measurements, corrected to a reference air density and for radioactive decay, was between 0,07% and 0,4% with respect to the mean values obtained during the eight months. The relative standard deviation of the single values belonging to a control measurement carried out on one day under constant ambient conditions amounts to approximately one fourth of the values quoted above. The current source was utilized in a number of laboratories in the PTB and proved its reliability for checking current measuring systems in dosimetry with ionization chambers. (orig.)

  6. Alternating Anderson-Richardson method: An efficient alternative to preconditioned Krylov methods for large, sparse linear systems

    CERN Document Server

    Suryanarayana, Phanish; Pask, John E

    2016-01-01

    We generalize the recently proposed Alternating Anderson-Jacobi (AAJ) method (Pratapa et al., J. Comput. Phys. (2016), 306, 43--54) to include preconditioning, and demonstrate its efficiency and scaling in the solution of large, sparse linear systems on parallel computers. The resulting preconditioned Alternating Anderson-Richardson (AAR) method reduces to the AAJ method for a particular choice of preconditioner. The AAR method employs Anderson extrapolation at periodic intervals within a preconditioned Richardson iteration to accelerate convergence. In this work, we develop a version of the method that is particularly well suited for scalable high-performance computing. In applications to Helmholtz and Poisson equations, we show that the strong and weak parallel scaling of AAR is superior to both Generalized Minimal Residual (GMRES) and Conjugate Gradient (CG) methods, using the same preconditioning, in large-scale parallel calculations employing up to 110,592 computational cores. Moreover, we find that the ...

  7. Ideal dosimetry system: dosimetry systems in current use

    International Nuclear Information System (INIS)

    In radiation processing - validation and process control (sterilization, food irradiation, etc.) depend on the measurement of absorbed dose. Measurements of absorbed dose shall be performed using a dosimetric system or systems having a known level of accuracy and precision (European standard EN552:1994). Lecture describes application of different dosimetry systems in the radiation processing of different materials

  8. West Coast Observing System (WCOS) ADCP Currents Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The West Coast Observing System (WCOS) project provides access to temperature and currents data collected at four of the five National Marine Sanctuary sites,...

  9. Current levels and composition profiles of PBDEs and alternative flame retardants in surface sediments from the Pearl River Delta, southern China: Comparison with historical data

    International Nuclear Information System (INIS)

    Polybrominated diphenyl ethers (PBDEs) and alternative flame retardants were measured in surface sediments collected during 2009–2010 from the Pearl River Delta, southern China (a large manufacturing base for electronics/electrical products), to evaluate the influence of China's RoHS directive (adopted in 2006) on their environmental occurrence. The concentrations in sediments from different water systems ranged from 3.67 to 2520 ng/g (average of 17.1–588 ng/g) for PBDEs and from 0.22 to 5270 ng/g (average of 11.3–454 ng/g) for the alternative retardants. Although the PBDE levels have decreased significantly compared with those in sediments collected in 2002 in this region, the levels of alternative decabromodiphenyl ethane (DBDPE) have exceeded those of BDE209 (two predominant halogenated flame retardants (HFRs) in China) in the majority of sediments. This finding suggests a different contaminant pattern of HFRs in current sediments due to the replacement of the deca-BDE mixture with DBDPE in this region. In addition, sediment concentrations of discontinued PBDEs in the rural area are clearly elevated due to e-waste dismantling. The congener profiles of PBDEs in the current sediments (with more abundant lower-brominated congeners) differed substantially from those in 2002 and from the technical products, suggesting that biological or photolytic debromination of PBDEs may have occurred in the environment. - Highlights: ► PBDE levels in sediments have decreased substantially since China's RoHS directive. ► Contamination of novel DBDPE has exceeded that of deca-BDE in the PRD sediments. ► The congener profiles of PBDEs in the sediments have changed significantly. ► Significant biological or photolytic degradation of PBDEs may occur in the environment

  10. Eddy Current System for Material Inspection and Flaw Visualization

    Science.gov (United States)

    Bachnak, R.; King, S.; Maeger, W.; Nguyen, T.

    2007-01-01

    Eddy current methods have been successfully used in a variety of non-destructive evaluation applications including detection of cracks, measurements of material thickness, determining metal thinning due to corrosion, measurements of coating thickness, determining electrical conductivity, identification of materials, and detection of corrosion in heat exchanger tubes. This paper describes the development of an eddy current prototype that combines positional and eddy-current data to produce a C-scan of tested material. The preliminary system consists of an eddy current probe, a position tracking mechanism, and basic data visualization capability. Initial test results of the prototype are presented in this paper.

  11. EVALUATION OF ALTERNATE STAINLESS STEEL SURFACE TREATMENTS FOR MASS SPECTROSCOPY AND OTHER TRITIUM SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Clark, E.; Mauldin, C.; Neikirk, K.

    2012-02-29

    There are specific components in the SRS Tritium Facilities that are required to introduce as few chemical impurities (such as protium and methane) as possible into the process gas. Two such components are the inlet systems for the mass spectroscopy facilities and hydrogen isotope mix standard containers. Two vendors now passivate stainless steel components for these systems, and both are relatively small businesses whose future viability can be questioned, which creates the need for new sources. Stainless steel containers were designed to evaluate alternate surface treatment vendors for tritium storage and handling for these high purity tritium systems. Five vendors applied their own 'best' surface treatments to two containers each - one was a current vendor, another was a chemical vapor deposited silicon coating, and the other three were electropolishing and chemical cleaning vendors. Pure tritium gas was introduced into all ten containers and the composition was monitored over time. The only observed impurities in the gas were some HT, less CT{sub 4}, and very small amounts of T{sub 2}O in all cases. The currently used vendor treated containers contained the least impurities. The chemical vapor deposited silicon treatment resulted in the highest impurity levels. Sampling one set of containers after about one month of tritium exposure revealed the impurity level to be nearly the same as that after more than a year of exposure - this result suggests that cleaning new stainless steel components by tritium gas contact for about a month may be a worthy operation.

  12. Alternating and direct current electrochemical studies of a wool wax-based corrosion preventive coating on aluminum alloy 2024

    Energy Technology Data Exchange (ETDEWEB)

    Su, P.C.; Devereux, O.F. [Univ. of Connecticut, Storrs, CT (United States). Dept. of Metallurgy and Materials Engineering

    1998-06-01

    The corrosion behavior of Al 2024-T3 treated with a wool wax (lanolin)-based corrosion preventive coating in aqueous 0.5 M sodium chloride was studied using electrochemical impedance spectroscopy (EIS) and direct current electrode polarization. DC measurements were modeled by three reactions: oxidation of aluminum, reduction of oxygen, and reduction of hydrogen. Alternating current behavior of untreated specimens was modeled using the Randles circuit, and that of inhibited specimens was modeled using parallel resistance-capacitance circuits representing the coating and the charge-transfer process. AC and DC estimates of the polarization resistance of coated specimens were 50 M{Omega}-cm{sup 2} and 32 M{Omega}-cm{sup 2}, respectively. AC and DC values for bare control specimens were of the order of 3 k{Omega}-cm{sup 2} and 15 k{Omega}-cm{sup 2}, respectively. The wool wax coating was found to be a very effective corrosion preventative for this alloy in the aqueous saline environment whether applied to freshly prepared surfaces or to corroded specimens removed from simulated service.

  13. Aneurysm Sac Pressure Measurement with Minimally Invasive Implantable Pressure Sensors: An Alternative to Current Surveillance Regimes after EVAR?

    International Nuclear Information System (INIS)

    Current protocols for surveillance after endovascular repair (EVAR) of abdominal aortic aneurysms are mostly based on costly and time-consuming imaging procedures and aim to detect adverse events such as graft migration, endoleaks or aneurysm sac enlargement. These imaging procedures are either associated with radiation exposure to the patients or may be harmful to the patient due to the use of iodine- or gadolinium-containing contrast agents. Furthermore the advantages of EVAR in the short term might be negated by the necessity for endograft surveillance over years. Thus, alternative modalities for follow-up are being investigated. One of these technologies provides pressure information directly from the aneurysm sac. This noninvasive, telemetric pressure sensing was tested in vitro as well as in first clinical trials and was able to identify successful aneurysm exclusion after EVAR. The telemetric pressure sensors showed a promising efficacy and accuracy in detecting type I and type III endoleaks and will help to clarify the clinical relevance of type II endoleaks. This article provides an overview of the in vitro sensors investigated as well as the first clinical trials and the sensors' potential to change the current endograft surveillance regimes

  14. Two-way shape memory effect and alternating current driving characteristics of a TiNi alloy spring

    Institute of Scientific and Technical Information of China (English)

    WANG Zhiguo; ZU Xiaotao

    2004-01-01

    Two-way shape memory effect (TWSME) was induced into the TiNi shape memory alloys (SMAs) spring by thermomechanical training after annealing treatment, which has promising application in micro-actuating fields. The TWSME spring can contract upon heating and extend upon cooling. The results show that there is an increase of the recovery ratio up to a maximum TWSME of 45%. During the training procedure, transformation temperatures and hysteresis were measured by different scanning calorimetry (DSC). The results show that As (reverse transformation start temperature) and Af (revere transformation finish temperature) shift to lower temperature after training. The intervals of Af-As and Ms-Mr (Ms and Mf are the martensite start and finish temperatures, respectively) increase and the heat of transformation decreases after training. The electrothermal driving characteristics of the TWSME springs were also investigated with alternating current density of 3.2-14.7 A/mm2. It is found that the time response and the maximum contraction ratio greatly depend on the magnitude of the electrical current density.

  15. Distributed Voltage and Current Control of Multi-Terminal High-Voltage Direct Current Transmission Systems

    OpenAIRE

    Andreasson, Martin; Nazari, Mohammad; Dimarogonas, Dimos V.; Sandberg, Henrik; Johansson, Karl H.; Ghandhari, Mehrdad

    2014-01-01

    High-voltage direct current (HVDC) is a commonly used technology for long-distance power transmission, due to its low resistive losses and low costs. In this paper, a novel distributed controller for multi-terminal HVDC (MTDC) systems is proposed. Under certain conditions on the controller gains, it is shown to stabilize the MTDC system. The controller is shown to always keep the voltages close to the nominal voltage, while assuring that the injected power is shared fairly among the converter...

  16. Large-scale current systems in the dayside Venus ionosphere

    Science.gov (United States)

    Luhmann, J. G.; Elphic, R. C.; Brace, L. H.

    1981-01-01

    The occasional observation of large-scale horizontal magnetic fields within the dayside ionosphere of Venus by the flux gate magnetometer on the Pioneer Venus orbiter suggests the presence of large-scale current systems. Using the measured altitude profiles of the magnetic field and the electron density and temperature, together with the previously reported neutral atmosphere density and composition, it is found that the local ionosphere can be described at these times by a simple steady state model which treats the unobserved quantities, such as the electric field, as parameters. When the model is appropriate, the altitude profiles of the ion and electron velocities and the currents along the satellite trajectory can be inferred. These results elucidate the configurations and sources of the ionospheric current systems which produce the observed large-scale magnetic fields, and in particular illustrate the effect of ion-neutral coupling in the determination of the current system at low altitudes.

  17. Design of air-core transformer for pulsed current system

    International Nuclear Information System (INIS)

    In this paper, a strip air-core pulse transformer is designed to convert the current. And, how it works and the process of making is elaborated in detail. The transformer contains leads, insulator, copper strip and supporting core. Under the conditions of the charging voltage 2500 V, 5.52 kA and 1.48 kA peak current of primary and secondary windings are obtained, and correspondingly, the current rising rate is 37 A/μs and 138 A/μs. It is supported by analysis and experiment that the transformer can reduce the requirement of the rising rate of the switching current effectively. So, the thyristor can be used in the pulse current system which has a high current rising rate and improve its performance on repetition and stability. (authors)

  18. Comparison of alternative offshore wind farms and HVDC systems

    Energy Technology Data Exchange (ETDEWEB)

    Bruns, M. [Technische Univ. Dresden (Germany); Lilje, P.; Poeller, M. [DIgSILENT GmbH, Gomaringen (Germany); Basteck, A. [Voith Turbo Wind GmbH und Co. KG, Crailsheim (Germany)

    2010-07-01

    This paper investigates the stability of offshore wind farms connected to the main power system via HVDC systems. Wind farms consisting of different ratios of directly connected synchronous machines and doubly-fed induction machines are considered. In addition, both conventional LCC- and VSC-type HVDC systems are considered. Furthermore, different control strategies are considered. Furthermore, different control strategies are considered for the VSC-based system, including constant frequency control and frequency regulation. The stability analysis is done by means of time-domain simulation. The maximum and minimum ratio of the two wind turbine technologies is found for each of the different HVDC systems. (orig.)

  19. Nuclear proliferation and civilian nuclear power. Report of the Nonproliferation Alternative Systems Assessment Program. Volume V. Economics and systems analysis

    International Nuclear Information System (INIS)

    This NASAP assessment considers the economics of alternative nuclear reactor and fuel-cycle systems in the light of possible patterns of uranium supply and energy demand, as well as the economic implications of improvng the proliferation resistance of the various systems. The assessment focuses on the costs of alternative nuclear technologies and the possible timing of their implementation, based on their economic attractiveness

  20. Current perspectives on post systems: a literature review.

    Science.gov (United States)

    Goracci, C; Ferrari, M

    2011-06-01

    This literature review summarizes the most recent and reliable evidence on post systems. A search was limited to review articles published over the last 10 years in dental journals with an impact factor. Papers cited in the initially retrieved review articles were also included if significant. Preservation of tooth tissue, presence of a ferrule effect, and adhesion are regarded as the most effective conditions for long-term success of post-endodontic restorations. Adhesively luted fibre-reinforced composite post restorations have demonstrated satisfactory survival rates over relatively long follow-up periods. The clinical effectiveness of such restorations has been mainly ascribed to the more biomimetic behaviour of fibre-reinforced composite posts that reduces the risk of vertical root fractures. The most common type of failure when using fibre posts is post debonding and it is generally agreed that achieving stable adhesion to intraradicular dentine is more challenging than to coronal dentine. Several factors related to endodontic treatment, root canal shape, post space preparation, post translucency, adhesive cement handling and curing may have an influence on the outcome of the luting procedure. The most reliable results in fibre post cementation are obtained by etch-and-rinse adhesives in combination with dual-cure resin cements. The use of self-adhesive resin cements has also been proposed. Simplification is an obvious advantage of these new materials. However, the durability of their bond still needs to be verified with long-term clinical studies. Several techniques for pre-treating the fibre-reinforced composite post surface have been tested with the aim of improving the bond strength at the post-core and post-cement interfaces. Silicoating followed by silanization currently appears to be the most effective and convenient method for this purpose. In conclusion, the available evidence validates the use of fibre posts as an alternative to metal posts and

  1. Evaluation of Current Controllers for Distributed Power Generation Systems

    DEFF Research Database (Denmark)

    Timbus, Adrian; Liserre, Marco; Teodorescu, Remus;

    2009-01-01

    This paper discusses the evaluation of different current controllers employed for grid-connected distributed power generation systems having variable input power, such as wind turbines and photovoltaic systems. The focus is mainly set on linear controllers such as proportional-integral, proportio......This paper discusses the evaluation of different current controllers employed for grid-connected distributed power generation systems having variable input power, such as wind turbines and photovoltaic systems. The focus is mainly set on linear controllers such as proportional....... First, in steady-state conditions, the contribution of controllers to the total harmonic distortion of the grid current is pursued. Further on, the behavior of controllers in the case of transient conditions like input power variations and grid voltage faults is also examined. Experimental results in...

  2. Preliminary Assessment of Equivalency for a New Eddy Current System

    International Nuclear Information System (INIS)

    The Steam Generator Management Program (SGMP) guidelines require that Examination Technique Specification Sheets (ETSS) define essential variables for equipment, techniques, and analysis. Examination techniques with essential variables that vary within the ranges identified in the ETSS are considered equivalent. Steam generator tubes have been inspected using the ZETEC system, which is qualified in ETSSs, in Korea. The Korea Hydro and Nuclear Power Co., Ltd. (KHNP) has developed a new eddy current testing system for steam generator tubing inspection. This system is composed of SM-25 fixture controller, eddy current tester, probe push-puller control system, data acquisition and analysis software. The control system of SM-25 remote fixture is used to place the guide-tube at the correct and accurate position of each steam generator tube. The eddy current tester is composed of synthesizer, analog processor, and analog-to digital conversion board. The probe push-puller system is used to move the bobbin and rotating probe for data acquisition. The newly developed data acquisition, analysis, and management programs are based on the Windows operating system, while the ZETEC on the Unix-based. This paper describes characteristics of the new system and preliminary assessment of equivalency to the qualified system in detail. The KHNP is developing a new eddy current testing system for steam generator tubing inspection. Performance of the new system should be verified in accordance with requirements for the equivalency in order to be used for field inspections. Preliminary assessment of equivalency was carried out in this study. The results show that the new system is satisfied with the equivalency requirements for bobbin probe data. Further study for rotating probe data will be conducted to determine whether the new system can be used for steam generator tubing inspection in nuclear power plants

  3. Nuclear-fueled circulatory support systems. XII. Current status

    International Nuclear Information System (INIS)

    Our laboratories have been engaged in development and in vivo testing of nuclear-fueled circulatory support systems. These efforts have focused on 4 major areas: (1) evaluations of the biologic effects of chronic intracorporeal heat and radiation; (2) the development of efficient and reliable energy converters (engines); (3) evaluations of the biocompatibility of the various system components, and (4) investigations of the hemodynamic effectiveness of the system in vivo. Previous in vivo experiments have been reported. Three systems are currently under investigation; each has undergone a number of modifications to improve overall thermal-mechanical efficiencies or to decrease physiologic alterations resulting from system size, intracorporeal heat and interactions between the prostheses and experimental animals. The purpose of this paper is to characterize the current systems and describe recent in vivo experiments

  4. Alternative schemes for low-footprint operating systems building

    OpenAIRE

    Rippert, Christophe; Deville, Damien; Grimaud, Gilles

    2004-01-01

    This paper presents two ways of building dedicated embedded operating systems. The constructive approach consists in starting from a minimal kernel and adding abstractions as they are needed, whereas the destructive approach promotes the idea of customizing an existing operating system by removing unnecessary abstractions. We compare these two approaches on the example of building an embedded Java operating system and discuss the pros and cons of each method. We conclude by exhibiting the wea...

  5. Wind-forced modeling studies of currents, meanders, eddies, and filaments of the Canary Current System

    OpenAIRE

    Buch, Eric J.

    1997-01-01

    Approved for public release; distribution is unlimited A high-resolution, multi-level, primitive equation ocean model is used to examine the response of an eastern boundary oceanic regime to both wind forcing and irregular coastline geometry. The focus of this study is the coastal region from 300 N to 42.50 N, a portion of the Canary Current System (CCS). To study the generation, evolution, and sustainment of the currents, meanders, eddies and filaments of the CCS, the model is forced from...

  6. Alternative Methodologies for LiDAR System Calibration

    OpenAIRE

    Jacky Chow; Ana Paula Kersting; Ki In Bang; Ayman Habib

    2010-01-01

    Over the last few years, LiDAR has become a popular technology for the direct acquisition of topographic information. In spite of the increasing utilization of this technology in several applications, its accuracy potential has not been fully explored. Most of current LiDAR calibration techniques are based on empirical and proprietary procedures that demand the system’s raw measurements, which may not be always available to the end-user. As a result, we can still observe systematic discrepanc...

  7. Optimization of simulated inventory systems: OptQuest and alternatives

    NARCIS (Netherlands)

    Kleijnen, J.P.C.; Wan, J.

    2006-01-01

    This article illustrates simulation optimization through an (s, S) inventory manage- ment system. In this system, the goal function to be minimized is the expected value of speci…c inventory costs. Moreover, speci…c constraints must be satis…ed for some random simulation responses, namely the servic

  8. Environmental impacts of alternative pricing systems for transport

    International Nuclear Information System (INIS)

    The Dutch Minister of Transport requested a platform of Dutch non-governmental organizations to recommend a new vehicle taxation scheme supported by the general public. This report documents an analysis of the environmental impacts of alternative pricing scenarios for car and freight traffic formulated by the platform, including congestion charges, car kilometre charges, and heavy duty vehicle charges. Major conclusions drawn from this analysis are, firstly, that kilometre charges for car owners, replacing today's road and vehicle purchase taxes, are effective in reducing emissions from road traffic. The size of environmental benefit of the proposed kilometre charge, however, is strongly determined by the design of the policy measure. Secondly, congestion charges on the main motorway network have minor effects on emissions from road traffic at a national scale and local air quality along motorways, both on the short (2010) and longer term (2020). Thirdly, the introduction of an environmental-performance related kilometre charge for heavy duty vehicles on the short term will result in a quicker renovation of the truck fleet and reduce emissions and improve local air quality along motorways. Introduction on the longer term will result in much smaller environmental impacts

  9. Nonequilibrium Microscopic Distribution of Thermal Current in Particle Systems

    KAUST Repository

    Yukawa, Satoshi

    2009-02-15

    A nonequilibrium distribution function of microscopic thermal current is studied by a direct numerical simulation in a thermal conducting steady state of particle systems. Two characteristic temperatures of the thermal current are investigated on the basis of the distribution. It is confirmed that the temperature depends on the current direction; Parallel temperature to the heat-flux is higher than antiparallel one. The difference between the parallel temperature and the antiparallel one is proportional to a macroscopic temperature gradient. ©2009 The Physical Society of Japan.

  10. Automatic control system for measuring currents produced by ionization chambers

    International Nuclear Information System (INIS)

    Ionization Chambers in current mode operation are usually used in Nuclear Metrology. Activity measurements are quickly performed by Ionization Chambers, with very good precision. For this purpose measurements of very low ionization currents, carried out by high quality instrumentation, are required. Usually, electrometers perform the current integration method under command of signals from an automation system, in order to reduce the measurement uncertainties. Among the measurement systems at the Laboratorio de Metrologia Nuclear (LMN) of IPEN, there are two ionization chamber systems. In the present work, an automation system developed for current integration measurements is described. This automation system is composed by software (graphic interface and control) and an electronic module connected to a microcomputer, by means of a commercial data acquisition card. Several test measurements were performed in order to determine the intrinsic uncertainty, linearity and stability of the system. Using calibrated radioactive solutions, the IG12/A20 chamber calibration factors for 18F and 153Sm were obtained, making possible to determine activities of these radionuclides. (author)

  11. Output Current Ripple Reduction Algorithms for Home Energy Storage Systems

    Directory of Open Access Journals (Sweden)

    Jin-Hyuk Park

    2013-10-01

    Full Text Available This paper proposes an output current ripple reduction algorithm using a proportional-integral (PI controller for an energy storage system (ESS. In single-phase systems, the DC/AC inverter has a second-order harmonic at twice the grid frequency of a DC-link voltage caused by pulsation of the DC-link voltage. The output current of a DC/DC converter has a ripple component because of the ripple of the DC-link voltage. The second-order harmonic adversely affects the battery lifetime. The proposed algorithm has an advantage of reducing the second-order harmonic of the output current in the variable frequency system. The proposed algorithm is verified from the PSIM simulation and experiment with the 3 kW ESS model.

  12. Transcranial alternating current stimulation (tACS increases risk taking behavior in the Balloon Analogue Risk Task

    Directory of Open Access Journals (Sweden)

    MichalLavidor

    2012-02-01

    Full Text Available The process of evaluating risks and benefits involves a complex neural network that includes the dorsolateral prefrontal cortex (DLPFC. It has been proposed that in conflict and reward situations, theta-band (4–8 Hz oscillatory activity in the frontal cortex may reflect an electrophysiological mechanism for coordinating neural networks monitoring behavior, as well as facilitating task-specific adaptive changes. The goal of the present study was to investigate the hypothesis that theta-band oscillatory balance between right and left frontal and prefrontal regions, with a predominance role to the right hemisphere, is crucial for regulatory control during decision-making under risk. In order to explore this hypothesis, we used transcranial Alternating Current Stimulation (tACS, a novel technique that provides the opportunity to explore the functional role of neuronal oscillatory activities and to establish a causal link between specific oscillations and functional lateralization in risky decision-making situations. For this aim, healthy participants were randomly allocated to one of three stimulation groups (LH stimulation / RH stimulation / Sham stimulation, with active AC stimulation delivered in a frequency-dependent manner (at 6.5 Hz; 1mA peak to-peak. During the AC stimulation, participants performed the Balloon Analog Risk Task. This experiment revealed that participants receiving LH stimulation displayed riskier decision-making style compared to sham and RH stimulation groups. However, there was no difference in decision-making behaviors between sham and RH stimulation groups. The current study extends the notion that DLPFC activity is critical for adaptive decision-making in the context of risk-taking and emphasis the role of theta-band oscillatory activity during risky decision-making situations.

  13. Alternatives for the battery cage system: a comparison of economic, environmental and societal performance

    NARCIS (Netherlands)

    Zijpp, van der A.J.; Mollenhorst, H.; Berentsen, P.B.M.; Boer, de I.J.M.

    2006-01-01

    The ban on the battery cage system in the European Union after 2012, mainly due to impaired hen welfare, forces farmers to change to alternative housing systems for laying hens. Large-scale introduction of more hen-friendly systems, however, requires a comparison of these systems on their economic,

  14. An Alternative Ice Protection System for Turbine Engine Inlets Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The innovation combines a new generation low power ice protection system with a novel path to certification that is based upon requirements that turbine engines be...

  15. Alternating current calorimeter for specific heat capacity measurements at temperatures below 10 K and pressures up to 10 GPa.

    Science.gov (United States)

    Umeo, Kazunori

    2016-06-01

    A developed alternating current calorimeter for measuring the absolute value of specific heat C of a very small sample under a pressure up to 10 GPa and low temperature below 10 K is described. A Bridgman anvil cell made of tungsten carbide with a top diameter of 3 mm is used. A hollow at the top prevents expansion of the sample space over the anvil top. Two chip resistors, which act as a thermometer and a heater, are mounted on the outer part of a copper-beryllium gasket with a frying pan-like shape. Thus, the thermometer is not pressurized. In order to isolate the gasket from the anvil thermally, diamond powder with a grain size of 0.25 μm is placed on the anvil top. Two jumps of C at the superconducting transitions of Pb (3.3 mg) and In (5.0 mg) are observed under various pressures up to 9 GPa, as clearly as those at the ambient pressure. PMID:27370464

  16. Enhancing Protein Capture Using a Combination of Nanoyeast Single-Chain Fragment Affinity Reagents and Alternating Current Electrohydrodynamic Forces.

    Science.gov (United States)

    Vaidyanathan, Ramanathan; Rauf, Sakandar; Grewal, Yadveer S; Spadafora, Lauren J; Shiddiky, Muhammad J A; Cangelosi, Gerard A; Trau, Matt

    2015-12-01

    New high-performance detection technologies and more robust protein capture agents can be combined to both rapidly and specifically capture and detect protein biomarkers associated with disease in complex biological samples. Here we demonstrate the use of recently developed recombinant affinity reagents, namely nanoyeast-scFv, in combination with alternating current electrohydrodynamic (ac-EHD)-induced shear forces, to enhance capture performance during protein biomarker analysis. The use of ac-EHD significantly improves fluid transport across the capture domain, resulting in enhanced sensor-target interaction and simultaneous displacement of nonspecific molecules from the electrode surface. We demonstrate this simple proof-of-concept approach for the capture and detection of Entamoeba histolytica antigens from disinfected stool, within a span of 5 min using an ac-EHD microfluidic device. Under an ac-EHD field, antigens were captured on a nanoyeast-scFv immobilized device and subsequently detected using a quantum dot conjugated antibody. This immunosensor specifically detected antigen in disinfected stool with low background noise at concentrations down to 58.8 fM with an interassay reproducibility (%RSD of n = 3) gold electrodes in disinfected stool. We predict this rapid and sensitive approach using these stable affinity reagents may offer a new methodology to detect protein disease biomarkers from biological matrices. PMID:26551436

  17. Alternating current characterization of nano-Pt(II) octaethylporphyrin (PtOEP) thin film as a new organic semiconductor

    Science.gov (United States)

    M, Dongol; M, M. El-Nahass; A, El-Denglawey; A, A. Abuelwafa; T, Soga

    2016-06-01

    Alternating current (AC) conductivity and dielectric properties of thermally evaporated Au/PtOEP/Au thin films are investigated each as a function of temperature (303 K–473 K) and frequency (50 Hz–5 MHz). The frequency dependence of AC conductivity follows the Jonscher universal dynamic law. The AC-activation energies are determined at different frequencies. It is found that the correlated barrier hopping (CBH) model is the dominant conduction mechanism. The variation of the frequency exponent s with temperature is analyzed in terms of the CBH model. Coulombic barrier height W m , hopping distance R ω , and the density of localized states N(E F) are valued at different frequencies. Dielectric constant ε 1(ω,T) and dielectric loss ε 2(ω,T) are discussed in terms of the dielectric polarization process. The dielectric modulus shows the non-Debye relaxation in the material. The extracted relaxation time by using the imaginary part of modulus (M″) is found to follow the Arrhenius law.

  18. Alternating current calorimeter for specific heat capacity measurements at temperatures below 10 K and pressures up to 10 GPa

    Science.gov (United States)

    Umeo, Kazunori

    2016-06-01

    A developed alternating current calorimeter for measuring the absolute value of specific heat C of a very small sample under a pressure up to 10 GPa and low temperature below 10 K is described. A Bridgman anvil cell made of tungsten carbide with a top diameter of 3 mm is used. A hollow at the top prevents expansion of the sample space over the anvil top. Two chip resistors, which act as a thermometer and a heater, are mounted on the outer part of a copper-beryllium gasket with a frying pan-like shape. Thus, the thermometer is not pressurized. In order to isolate the gasket from the anvil thermally, diamond powder with a grain size of 0.25 μm is placed on the anvil top. Two jumps of C at the superconducting transitions of Pb (3.3 mg) and In (5.0 mg) are observed under various pressures up to 9 GPa, as clearly as those at the ambient pressure.

  19. Transcranial Alternating Current Stimulation in Patients with Chronic Disorder of Consciousness: A Possible Way to Cut the Diagnostic Gordian Knot?

    Science.gov (United States)

    Naro, Antonino; Bramanti, Placido; Leo, Antonino; Russo, Margherita; Calabrò, Rocco Salvatore

    2016-07-01

    Unresponsive wakefulness syndrome (UWS) is a chronic disorder of consciousness (DOC) characterized by a lack of awareness and purposeful motor behaviors, owing to an extensive brain connectivity impairment. Nevertheless, some UWS patients may retain residual brain connectivity patterns, which may sustain a covert awareness, namely functional locked-in syndrome (fLIS). We evaluated the possibility of bringing to light such residual neural networks using a non-invasive neurostimulation protocol. To this end, we enrolled 15 healthy individuals and 26 DOC patients (minimally conscious state-MCS- and UWS), who underwent a γ-band transcranial alternating current stimulation (tACS) over the right dorsolateral prefrontal cortex. We measured the effects of tACS on power and partial-directed coherence within local and long-range cortical networks, before and after the protocol application. tACS was able to specifically modulate large-scale cortical effective connectivity and excitability in all the MCS participants and some UWS patients, who could be, therefore, considered as suffering from fLIS. Hence, tACS could be a useful approach in supporting a DOC differential diagnosis, depending on the level of preservation of the cortical large-scale effective connectivity. PMID:27062669

  20. W-314, waste transfer alternative piping system description

    International Nuclear Information System (INIS)

    It is proposed that the reliability, operability, and flexibility of the Retrieval Transfer System be substantially upgraded by replacing the planned single in-farm pipeline from the AN-AY-AZ-(SY) Tank Farm Complex to the AP Farm with three parallel pipelines outside the tank farms. The proposed system provides simplified and redundant routes for the various transfer missions, and prevents the risk of transfer gridlock when the privatization effort swings into full operation

  1. W-314, waste transfer alternative piping system description

    Energy Technology Data Exchange (ETDEWEB)

    Papp, I.G.

    1998-04-30

    It is proposed that the reliability, operability, and flexibility of the Retrieval Transfer System be substantially upgraded by replacing the planned single in-farm pipeline from the AN-AY-AZ-(SY) Tank Farm Complex to the AP Farm with three parallel pipelines outside the tank farms. The proposed system provides simplified and redundant routes for the various transfer missions, and prevents the risk of transfer gridlock when the privatization effort swings into full operation.

  2. ALTERNATIVE METHODS FOR CONDUCTING COMPARATIVE ANALYSES OF CADASTRAL SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The conception of an efficient cadastral system is an important element in the development of each coun-try. It is crucial for the efficient operation of the real estate market-the security and liberty of making transactions, register-ing a property, planning operations, the introduction of an ad valorem tax on property and more rational use of space. InEurope there are different types of cadastral systems, because the countries in Europe have different cultural back-grounds, different economical and social backgrounds. Through the centuries, many types of cadastral systems evolvedand their differences often depend upon local cultural heritage, physical geography, land use, technology, etc. Compara-tive analyses of cadastral systems have been the subjects of many publications and studies in world literature. It was as-sessed that the useful tools in conducting comparative analyses of various cadastral systems include the procedures of statisti-cal inference. This paper presents the results of a project to compare the performance of ten cadastral systems international-ly by creating appropriate integrated indicators of a cadastral system using statistical technique. Such indicators willmake it possible to compare different cadastral systems and present them hierarchically in relation to their quality, struc-ture, as well as legal, organizational and technological solutions. From a good number of methods available, techniquesoriginating from two spheres of statistic inference were selected: distribution free methods and multivariate analysis meth-ods. For analyses with the distribution free methods, FRIEDMAN's test (FRIENDMAN's non-parametric variance analy-sis) as well as KENDALL's test (KENDALL's compatibility ratio) were selected. For analyses with the multivariate analy-sis methods, factor analysis was selected.

  3. Alternatives to speech in low bit rate communication systems

    OpenAIRE

    Lopes, Cristina Videira; Aguiar, Pedro M. Q.

    2010-01-01

    This paper describes a framework and a method with which speech communication can be analyzed. The framework consists of a set of low bit rate, short-range acoustic communication systems, such as speech, but that are quite different from speech. The method is to systematically compare these systems according to different objective functions such as data rate, computational overhead, psychoacoustic effects and semantics. One goal of this study is to better understand the nature of human commun...

  4. System study of alternative waste management techniques: Final report

    International Nuclear Information System (INIS)

    This report summarizes the important results achieved in conjunction with the Research and Development Priority ''Alternative Waste Management Techniques'' sponsored by the Federal Ministry of Research and Technology from 1981 to 1984. The subject of these studies was solely ''direct disposal'' of spent fuel elements. For this purpose a reference concept was selected from a variety of possible processes and engineered in detailed form by firms in the nuclear industry. Those who worked on the engineering concepts consider this waste management method technically feasible. Several disposal casks have been fabricated. The basic licensability of direct disposal can be evaluated on the basis of the documentation developed by the companies. The direct disposal method was compared with the ''integrated waste management concept'' using reference fuel cycles with respect to the following criteria: radiological safety and nuclear material safeguards and, in addition, economic and energy-policy aspects. It was found that with respect to radiological safety, including the long-term safety of the final repository, there are no significant differences between the two fuel cycles with and without reprocessing. With respect to the nuclear material safeguards of a final repository containing spent fuel elements, there are still a number of unanswered questions. From an economic standpoint, direct disposal will be more economical in the foreseeable future than integrated waste management. Quantification of the effects of one or the other waste management method on the national economy is not necessarily possible. Reprocessing is supported primarily by technological and energy-policy considerations. On the basis of the results, the conclusion is reached that reprocessing should be pursued further, but that at the same time direct disposal should be developed to the point of practical maturity

  5. Output Current Ripple Reduction Algorithms for Home Energy Storage Systems

    OpenAIRE

    Jin-Hyuk Park; Kyo-Beum Lee; Hae-Gwang Jeong

    2013-01-01

    This paper proposes an output current ripple reduction algorithm using a proportional-integral (PI) controller for an energy storage system (ESS). In single-phase systems, the DC/AC inverter has a second-order harmonic at twice the grid frequency of a DC-link voltage caused by pulsation of the DC-link voltage. The output current of a DC/DC converter has a ripple component because of the ripple of the DC-link voltage. The second-order harmonic adversely affects the battery lifetime. The propos...

  6. Current distribution in systems with anomalous diffusion: renormalization group approach

    International Nuclear Information System (INIS)

    We investigate the asymptotic properties of the large deviation function of the integrated particle current in systems, in or out of thermal equilibrium, whose dynamics exhibits anomalous diffusion. The physical systems covered by our study include mutually repelling particles with a drift, a driven lattice gas displaying a continuous nonequilibrium phase transition and particles diffusing in an anisotropic random advective field. It is exemplified how renormalization group techniques allow for a systematic determination of power laws in the corresponding current large deviation functions. We show that the latter are governed by known universal scaling exponents, specifically the anomalous dimension of the noise correlators

  7. Experimental study on superconducting fault current limiting transformer for fault current suppression and system stability improvement

    Science.gov (United States)

    Kagawa, H.; Hayakawa, N.; Kashima, N.; Nagaya, S.; Okubo, H.

    2002-08-01

    We have been developing a superconducting fault current limiting transformer (SFCLT) with 3-phase, 500/275 kV, 625 MVA and optimized the main parameters by EMTP simulation. In this paper, we designed and fabricated an experimental scale-down model of SFCLT with 3-phase, 275/105 V, 6.25 kVA, using NbTi superconducting wire. We introduced the experimental model SFCLT into a transient network analyzer consisted of synchronous generators, transformers, transmission lines, circuit breakers and an infinite bus. It was revealed that experimental model had effective function-parameters as was simulated and experimental results clarified the effectiveness of SFCLT having both functions of the fault current suppression and the system stability improvement in a future superconducting power system.

  8. GREEN CATALYZED OXIDATION OF HYDROCARBONS IN ALTERNATIVE SOLVENT SYSTEMS GENERATED BY PARIS II

    Science.gov (United States)

    Green Catalyzed Oxidation of Hydrocarbons in Alternative Solvent Systems Generated by PARIS IIMichael A. Gonzalez*, Thomas M. Becker, and Paul F. Harten; Sustainable Technology Division, Office of Research and Development; United States Environmental Protection Agency, 26...

  9. Use of Augmentative and Alternative Communication Systems in Preschool: teacher perceptions

    Directory of Open Access Journals (Sweden)

    Munique Massaro

    2013-06-01

    Full Text Available Augmentative and Alternative Communication Resources have proven to be helpful in the insertion of students with disabilities and complex communication needs into a variety of pedagogical activities and expand the skills and competencies of the teacher in the teaching-learning. The objective of this research was to identify the perception of teachers regarding the use of augmentative and alternative communication during an intervention program in Preschool. Participants were a special class of Preschool students with disabilities and severe communication complexity, along with their teacher and the researcher. For the development of this research, a Alternative Communication Program was applied. The teacher was provided with systematic guidance concerning language and communication. In a collaborative process, three children’s songs were selected according to the teacher’s pedagogical planning and adapted resources through Augmentative and Alternative Communication Systems. During the intervention program, assisted evaluations also took place immediately after the activities with the music. The data were collected in audio recordings. For data analysis, content analysis was carried out resulting in the outlining of themes and sub-themes. Results indicated that the teacher identified that Augmentative and Alternative Communication Systems can to facilitate expression abilities of students with disabilities; that Augmentative and Alternative Communication Systems can be used by children in Preschool; and that resources adapted through augmentative and alternative communication systems should be in accordance with the specificities of students.

  10. Environmental and economic comparisons of the satellite power system and six alternative energy technologies

    Science.gov (United States)

    Whitfield, R. G.; Habegger, L. J.; Levine, E. P.; Tanzman, E.

    1981-04-01

    The satellite power system (SPS) was compared with alternative systems on life cycle cost and environmental impacts. Environmental and economic effects are evaluated and subdivided into the following issue areas: human health and safety, environmental welfare, resources (land, materials, energy, water, labor), macroeconomics, socioeconomics, and institutional. These evaluations are based on technology characterization data and alternative futures scenarios, developed as part of CDEP. The technologies and the scenarios are described. The cost and performance of the SPS and the alternative technologies provide the basis of the macroeconomic analyses.

  11. Measurement system of high voltage and high current measurements at INMETRO - Brazilian Institute for Metrology, Standardization and Industrial Quality; Sistema de medicao de alta tensao e alta corrente do INMETRO - Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Vitorio, Patricia Cals de O.; Franca, Ademir Martins de; Soares, Marco Aurelio; Pereira, Luiz Napoleao; Costa, Danielli Guimaraes; Moreira, Giselle Cobica; Nascimento, Paulo Roberto Mesquita [Instituto Nacional de Metrologia, Normalizacao e Qualidade Industrial (DIMCI/INMETRO), Duque de Caxias, RJ (Brazil). Diretoria de Metrologia Cientifica e Industrial], E-mail: latra@inmetro.gov.br

    2009-07-01

    This work presents the basic characteristics and uncertainties of the calibration equipment in high voltage and high current available at the INMETRO: system of measurement in alternating high voltage up to 200 kV, system of measurement in alternating current up to 2 k A, and system of measurement in continuous high voltage up to 150 kV.

  12. Coherent Structures and Larval Transport in the California Current System

    OpenAIRE

    Harrison, Cheryl S.

    2012-01-01

    In the California Current system (CCS), coherent structures such as jets and eddies strongly control the biological response to coastal upwelling. One of the outstanding problems in marine ecology is to understand the mechanisms of larval transport. Details of transport dynamics from nearshore to offshore, and subsequent delivery of coastally spawned propagules back to favorable settlement areas, strongly control marine population dynamics. Recent developments in applied dynamical systems all...

  13. An accurate continuous calibration system for high voltage current transformer

    International Nuclear Information System (INIS)

    A continuous calibration system for high voltage current transformers is presented in this paper. The sensor of this system is based on a kind of electronic instrument current transformer, which is a clamp-shape air core coil. This system uses an optical fiber transmission system for its signal transmission and power supply. Finally the digital integrator and fourth-order convolution window algorithm as error calculation methods are realized by the virtual instrument with a personal computer. It is found that this system can calibrate a high voltage current transformer while energized, which means avoiding a long calibrating period in the power system and the loss of power metering expense. At the same time, it has a wide dynamic range and frequency band, and it can achieve a high accuracy measurement in a complex electromagnetic field environment. The experimental results and the on-site operation results presented in the last part of the paper, prove that it can reach the 0.05 accuracy class and is easy to operate on site.

  14. Testing Alternative Dynamic Systems for Modelling Tourism Demand

    OpenAIRE

    Maria M. De Mello; Natercia Fortuna

    2005-01-01

    The goals in this paper are to contribute an empirical study of tourism demand dynamics, and to point out areas where the scrutiny of relationships between theoretical and empirical considerations are likely to produce new insights in this area of research. A flexible general form of a Dynamic Almost Ideal Demand System (DAIDS) is derived to analyse the UK tourism demand for its geographically proximate neighbours Portugal, Spain and France, in the period 1969-1997. Nested within the general ...

  15. Banana production systems: identification of alternative systems for more sustainable production.

    Science.gov (United States)

    Bellamy, Angelina Sanderson

    2013-04-01

    Large-scale, monoculture production systems dependent on synthetic fertilizers and pesticides, increase yields, but are costly and have deleterious impacts on human health and the environment. This research investigates variations in banana production practices in Costa Rica, to identify alternative systems that combine high productivity and profitability, with reduced reliance on agrochemicals. Farm workers were observed during daily production activities; 39 banana producers and 8 extension workers/researchers were interviewed; and a review of field experiments conducted by the National Banana Corporation between 1997 and 2002 was made. Correspondence analysis showed that there is no structured variation in large-scale banana producers' practices, but two other banana production systems were identified: a small-scale organic system and a small-scale conventional coffee-banana intercropped system. Field-scale research may reveal ways that these practices can be scaled up to achieve a productive and profitable system producing high-quality export bananas with fewer or no pesticides. PMID:23055273

  16. Social response to nuclear power and alternative energy systems

    International Nuclear Information System (INIS)

    Phase I of this study analyzed attitudes and beliefs of respondents drawn from Metro Manila. The second phase utilized a sample drawn from residents near a geothermal power plant site in the Southern Philippines. Four dimensions of beliefs (psychological environmental risks, technological benefits/development, economic benefits/implications, and socio-political/implications/benefit) were identified through factor analysis of beliefs items on nuclear energy and refined empirically to determine perceptions of respondents about all other energy systems. Identification of the relationship between dimensions provided insight into the shared perceptions about each energy system held by the various groups of respondents. The overall attitude of the respondents towards energy systems (nuclear, solar, hydro, geothermal and oil) was determined using three attitude measures: the Fishbein model, Osgood's semantic differential technique, and direct response to unfavorability/favorability scale. The belief dimensions were correlated with the attitude measures to determine the degree of contribution to attitude. A comparative analysis was made to different attitudes and beliefs held by the PRO and CON nuclear groups and by the subsamples: university students, science teachers and barangay leaders of Metro Manila sample. Attitudes and beliefs relating to the demographic variables were also examined for the two samples. (author)

  17. Public attitudes towards nuclear power and alternative energy systems

    International Nuclear Information System (INIS)

    Phase I of this study analyzed attitudes and beliefs of respondents drawn from Metro-Manila. The second phase utilized a sample drawn from residents near a geothermal power plant site in Southern Philippines. Four dimensions of beliefs (psychological/environmental risks, technological benefits/development, economic benefits/implications and socio-political implications/benefits) were identified through factor analysis of belief items on nuclear energy and refined empirically to determine perceptions of respondents about all energy systems. Identification of the relationships between dimensions provided insight into the shared perceptions about each energy system held by the various groups of respondents. The overall attitude of the respondents towards energy systems (nuclear, solar, hydro, geothermal and oil) was determined using three attitude measures: Fishbein model, Osgood's semantic differential technique, and direct response to unfavorability/favorability scale. The belief dimensions were correlated with the attitude measures to determine the degree of contribution of each dimension to attitude. A comparative analysis was made to differentiate attitudes and beliefs held by the PRO and CON nuclear groups, and by the subsamples: university students, science teachers and barangay leaders of the Metro-Manila sample. Attitudes and beliefs relating to the demographic variables were also examined for the two samples. (author)

  18. LLNL current meter array--concept and system description

    Energy Technology Data Exchange (ETDEWEB)

    Mantrom, D.D. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    A measurement capability using a horizontal array of 10 S4 current meters mounted on a stiff floating structure with 35 m aperture has been developed to support interpretation of radar imaging of surface effects associated with internal waves. This system has been fielded three times and most recently, has collected data alongside the sea-surface footprint of a land-fixed radar imaging ship-generated internal waves. The underlying need for this measurement capability is described. The specifications resulting from this need are presented and the engineering design and deployment procedures of the platform and systems that resulted are described The current meter data are multiplexed along with meteorological and system status data on board the floating platform and are telemetered to a shore station and on to a data acquisition system. The raw data are recorded, and are then processed to form space-time images of current and strain rate (a spatial derivative of the current field). Examples of raw and processed data associated with ship-generated internal waves are presented.

  19. Current Strategic Business Plan for the Implementation of Digital Systems.

    Science.gov (United States)

    Library of Congress, Washington, DC. National Library Service for the Blind and Physically Handicapped.

    This document presents a current strategic business plan for the implementation of digital systems and services for the free national library program operated by the National Library Service for the Blind and Physically Handicapped, Library of Congress, its network of cooperating regional and local libraries, and the United States Postal Service.…

  20. Multiple pole electromagnetic propulsion system with separated ballistic guidance and electrical current contact surfaces

    Science.gov (United States)

    Sims, Jr., James R.

    2008-07-15

    An electromagnetic propulsion system is disclosed having separate rails for ballistic guidance and for carrying current. In this system, one or more pairs of ballistic guidance rails are provided, with each ballistic guidance rail having a pair of current carrying rails joined to it to form a combined rail. Each combined rail is separated electrically from adjacent combined rails by electrically insulating blocks. Each of the current carrying rails in a given combined rail pair have the same electrical polarity, and the polarities alternate between adjacent combined rails. Armatures contact current carrying rails to complete the circuit to generate the accelerating Lorentz force on the armatures. Bore riders on the sabot and/or projectile are in contact with the ballistic guide rails. Separation of the current carrying and ballistic guidance functions increases resistance of the system to rail movement and bending, as well as reduced wear/damage to the rails. In further embodiments, a circumferential over wrap providing compressive force on the rails further increases resistance of the system to rail movement and bending.

  1. Groundwater thermal-effective injection systems in shallow aquifers: possible alternatives to vertical water wells

    Science.gov (United States)

    Lo Russo, Stefano; Taddia, Glenda; Cerino Abdin, Elena

    2014-05-01

    Urbanized areas have environmental features that may influence the development of low-enthalpy geothermal systems and the choice of the most suitable among the available (roughly earth-coupled closed-loop and groundwater open-loop type). In particular, if compared to less anthropized areas, some characteristic urban elements require particular attention: underground extensive use, contamination of groundwater, interference between the systems, authorization procedures and planning restrictions, the competition with cogeneration systems and the impact on emissions of pollutants. In this general context, the increasing implementation in several areas of the world of the open-loop groundwater heat pumps technology which discharge into the aquifer for cooling and heating buildings, could potentially cause, even in the short term, a significant environmental impact associated with thermal interference with groundwater, particularly in the shallow aquifers. The discharge of water at different temperatures compared to baseline (warmer in summer and colder in winter) poses a number of problems in relation to the potential functionality of many existing situations of use of the groundwater (drinking water wells, agricultural, industrial, etc.). In addition, there may be cases of interference between systems, especially in the more densely urbanized areas. Appropriate hydrogeological investigations should be performed for the characterization of the main hydrogeological parameters of the subsoil at the considered site in order to minimize the environmental impact of discharges into aquifers. The current Italian legislation related to withdrawals and discharges into aquifers designs a framework suitable for the protection of groundwater and induce deciding the best configuration of the plant with a case by case approach. An increased contact area between the dispersant system and the ground makes it possible to affect a greater volume of aquifer and, consequently, reduce the

  2. Market scenarios and alternative administrative frameworks for US educational satellite systems

    Science.gov (United States)

    Walkmeyer, J. E., Jr.; Morgan, R. P.; Singh, J. P.

    1975-01-01

    Costs and benefits of developing an operational educational satellite system in the U.S. are analyzed. Scenarios are developed for each educational submarket and satellite channel and ground terminal requirements for a large-scale educational telecommunications system are estimated. Alternative organizational frameworks for such a system are described.

  3. ALTERNATE HIGH EFFICIENCY PARTICULATE AIR (HEPA) FILTRATION SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Bruce Bishop; Robert Goldsmith; Karsten Nielsen; Phillip Paquette

    2002-08-16

    In Phase IIA of this project, CeraMem has further developed and scaled up ceramic HEPA filters that are appropriate for use on filtration of vent gas from HLW tanks at DOE sites around the country. This work included procuring recrystallized SiC monoliths, developing membrane and cement materials, and defining a manufacturing process for the production of prototype full sizes HEPA filters. CeraMem has demonstrated that prototype full size filters can be manufactured by producing 9 full size filters that passed DOP aerosol testing at the Oak Ridge Filter Test Facility. One of these filters was supplied to the Savannah River Technical Center (SRTC) for process tests using simulated HLW tank waste. SRTC has reported that the filter was regenerable (with some increase in pressure drop) and that the filter retained its HEPA retention capability. CeraMem has also developed a Regenerable HEPA Filter System (RHFS) design and acceptance test plan that was reviewed by DOE personnel. The design and acceptance test plan form the basis of the system proposal for follow-on work in Phase IIB of this project.

  4. An alternative respiratory sounds classification system utilizing artificial neural networks

    Directory of Open Access Journals (Sweden)

    Rami J Oweis

    2015-04-01

    Full Text Available Background: Computerized lung sound analysis involves recording lung sound via an electronic device, followed by computer analysis and classification based on specific signal characteristics as non-linearity and nonstationarity caused by air turbulence. An automatic analysis is necessary to avoid dependence on expert skills. Methods: This work revolves around exploiting autocorrelation in the feature extraction stage. All process stages were implemented in MATLAB. The classification process was performed comparatively using both artificial neural networks (ANNs and adaptive neuro-fuzzy inference systems (ANFIS toolboxes. The methods have been applied to 10 different respiratory sounds for classification. Results: The ANN was superior to the ANFIS system and returned superior performance parameters. Its accuracy, specificity, and sensitivity were 98.6%, 100%, and 97.8%, respectively. The obtained parameters showed superiority to many recent approaches. Conclusions: The promising proposed method is an efficient fast tool for the intended purpose as manifested in the performance parameters, specifically, accuracy, specificity, and sensitivity. Furthermore, it may be added that utilizing the autocorrelation function in the feature extraction in such applications results in enhanced performance and avoids undesired computation complexities compared to other techniques.

  5. ALTERNATE HIGH EFFICIENCY PARTICULATE AIR (HEPA) FILTRATION SYSTEM

    International Nuclear Information System (INIS)

    In Phase IIA of this project, CeraMem has further developed and scaled up ceramic HEPA filters that are appropriate for use on filtration of vent gas from HLW tanks at DOE sites around the country. This work included procuring recrystallized SiC monoliths, developing membrane and cement materials, and defining a manufacturing process for the production of prototype full sizes HEPA filters. CeraMem has demonstrated that prototype full size filters can be manufactured by producing 9 full size filters that passed DOP aerosol testing at the Oak Ridge Filter Test Facility. One of these filters was supplied to the Savannah River Technical Center (SRTC) for process tests using simulated HLW tank waste. SRTC has reported that the filter was regenerable (with some increase in pressure drop) and that the filter retained its HEPA retention capability. CeraMem has also developed a Regenerable HEPA Filter System (RHFS) design and acceptance test plan that was reviewed by DOE personnel. The design and acceptance test plan form the basis of the system proposal for follow-on work in Phase IIB of this project

  6. Increase in short-term memory capacity induced by down-regulating individual theta frequency via transcranial alternating current stimulation.

    Science.gov (United States)

    Vosskuhl, Johannes; Huster, René J; Herrmann, Christoph S

    2015-01-01

    Working memory (WM) and short-term memory (STM) supposedly rely on the phase-amplitude coupling (PAC) of neural oscillations in the theta and gamma frequency ranges. The ratio between the individually dominant gamma and theta frequencies is believed to determine an individual's memory capacity. The aim of this study was to establish a causal relationship between the gamma/theta ratio and WM/STM capacity by means of transcranial alternating current stimulation (tACS). To achieve this, tACS was delivered at a frequency below the individual theta frequency. Thereby the individual ratio of gamma to theta frequencies was changed, resulting in an increase of STM capacity. Healthy human participants (N = 33) were allocated to two groups, one receiving verum tACS, the other underwent a sham control protocol. The electroencephalogram (EEG) was measured before stimulation and analyzed with regard to the properties of PAC between theta and gamma frequencies to determine individual stimulation frequencies. After stimulation, EEG was recorded again in order to find after-effects of tACS in the oscillatory features of the EEG. Measures of STM and WM were obtained before, during and after stimulation. Frequency spectra and behavioral data were compared between groups and different measurement phases. The tACS- but not the sham stimulated group showed an increase in STM capacity during stimulation. WM was not affected in either groups. An increase in task-related theta amplitude after stimulation was observed only for the tACS group. These augmented theta amplitudes indicated that the manipulation of individual theta frequencies was successful and caused the increase in STM capacity. PMID:26005411

  7. Increase in short-term memory capacity induced by down-regulating individual theta frequency via transcranial alternating current stimulation

    Directory of Open Access Journals (Sweden)

    Johannes Vosskuhl

    2015-05-01

    Full Text Available Working memory (WM and short-term memory (STM supposedly rely on the phase-amplitude coupling of neural oscillations in the theta and gamma frequency ranges. The ratio between the individually dominant gamma and theta frequencies is believed to determine an individual’s memory capacity. The aim of this study was to establish a causal relationship between the gamma/theta ratio and WM/STM capacity by means of transcranial alternating current stimulation (tACS. To achieve this, tACS was delivered at a frequency below the individual theta frequency. Thereby the individual ratio of gamma to theta frequencies was changed, resulting in an increase of STM capacity. Healthy human participants (N=33 were allocated to two groups, one receiving verum tACS, the other underwent a sham control protocol. The electroencephalogram (EEG was measured before stimulation and analyzed with regard to the properties of phase-amplitude coupling between theta and gamma frequencies to determine individual stimulation frequencies. After stimulation, EEG was recorded again in order to find after-effects of tACS in the oscillatory features of the EEG. Measures of STM and WM were obtained before, during and after stimulation. Frequency spectra and behavioral data were compared between groups and different measurement phases. The tACS- but not the sham stimulated group showed an increase in STM capacity during stimulation. WM was not affected in either groups. An increase in task-related theta amplitude after stimulation was observed only for the tACS group. These augmented theta amplitudes indicated that the manipulation of individual theta frequencies was successful and caused the increase in STM capacity.

  8. Survey of Digital Feedback Systems in High Current Storage Rings

    International Nuclear Information System (INIS)

    In the last decade demand for brightness in synchrotron light sources and luminosity in circular colliders led to construction of multiple high current storage rings. Many of these new machines require feedback systems to achieve design stored beam currents. In the same time frame the rapid advances in the technology of digital signal processing allowed the implementation of these complex feedback systems. In this paper I concentrate on three applications of feedback to storage rings: orbit control in light sources, coupled-bunch instability control, and low-level RF control. Each of these applications is challenging in areas of processing bandwidth, algorithm complexity, and control of time-varying beam and system dynamics. I will review existing implementations as well as comment on promising future directions

  9. Self-Organizing Maps-based ocean currents forecasting system

    Science.gov (United States)

    Vilibić, Ivica; Šepić, Jadranka; Mihanović, Hrvoje; Kalinić, Hrvoje; Cosoli, Simone; Janeković, Ivica; Žagar, Nedjeljka; Jesenko, Blaž; Tudor, Martina; Dadić, Vlado; Ivanković, Damir

    2016-03-01

    An ocean surface currents forecasting system, based on a Self-Organizing Maps (SOM) neural network algorithm, high-frequency (HF) ocean radar measurements and numerical weather prediction (NWP) products, has been developed for a coastal area of the northern Adriatic and compared with operational ROMS-derived surface currents. The two systems differ significantly in architecture and algorithms, being based on either unsupervised learning techniques or ocean physics. To compare performance of the two methods, their forecasting skills were tested on independent datasets. The SOM-based forecasting system has a slightly better forecasting skill, especially during strong wind conditions, with potential for further improvement when data sets of higher quality and longer duration are used for training.

  10. Self-Organizing Maps-based ocean currents forecasting system.

    Science.gov (United States)

    Vilibić, Ivica; Šepić, Jadranka; Mihanović, Hrvoje; Kalinić, Hrvoje; Cosoli, Simone; Janeković, Ivica; Žagar, Nedjeljka; Jesenko, Blaž; Tudor, Martina; Dadić, Vlado; Ivanković, Damir

    2016-01-01

    An ocean surface currents forecasting system, based on a Self-Organizing Maps (SOM) neural network algorithm, high-frequency (HF) ocean radar measurements and numerical weather prediction (NWP) products, has been developed for a coastal area of the northern Adriatic and compared with operational ROMS-derived surface currents. The two systems differ significantly in architecture and algorithms, being based on either unsupervised learning techniques or ocean physics. To compare performance of the two methods, their forecasting skills were tested on independent datasets. The SOM-based forecasting system has a slightly better forecasting skill, especially during strong wind conditions, with potential for further improvement when data sets of higher quality and longer duration are used for training. PMID:26979129

  11. Ecology of Fungus Gnats (Bradysia spp. in Greenhouse Production Systems Associated with Disease-Interactions and Alternative Management Strategies

    Directory of Open Access Journals (Sweden)

    Raymond A. Cloyd

    2015-04-01

    Full Text Available Fungus gnats (Bradysia spp. are major insect pests of greenhouse-grown horticultural crops mainly due to the direct feeding damage caused by the larvae, and the ability of larvae to transmit certain soil-borne plant pathogens. Currently, insecticides and biological control agents are being used successively to deal with fungus gnat populations in greenhouse production systems. However, these strategies may only be effective as long as greenhouse producers also implement alternative management strategies such as cultural, physical, and sanitation. This includes elimination of algae, and plant and growing medium debris; placing physical barriers onto the growing medium surface; and using materials that repel fungus gnat adults. This article describes the disease-interactions associated with fungus gnats and foliar and soil-borne diseases, and the alternative management strategies that should be considered by greenhouse producers in order to alleviate problems with fungus gnats in greenhouse production systems.

  12. Alternative definitions of kinetic parameters for accelerator driven systems

    International Nuclear Information System (INIS)

    Highlights: ► New definition of kinetic parameters for accelerator driven systems. ► Difference between effective and average delayed neutron fraction. ► Difference between effective and average prompt neutron lifetime. ► Effect of the neutron source (Cf, D–D, D–T) on ksrc. ► Effect of the (n, xn) reactions and source energy-angle distribution on ksrc. - Abstract: This study introduces a new formulation of kinetic parameters for accelerator driven systems and it is structured into two parts. The first part is dedicated to the classic definition of the kinetic parameters and compares different calculation methodologies. The second part considers a new definition of the kinetic parameters for subcritical assemblies, with particular emphasis on the delayed neutron fraction and the prompt neutron lifetime. This new definition takes into account neutrons from the external neutron source and (n, xn) reactions, which increase the fraction of prompt neutrons. The developed theoretical framework has been applied by Monte Carlo and deterministic calculations to the YALINA Thermal subcritical assembly located in Belarus. This facility can be driven by californium, deuterium–deuterium (D–D), or deuterium–tritium (D–T) external neutron sources. For the D–T neutron source, (n, xn) reactions must be taken into account in order to produce accurate results because the average energy of D–T source neutrons is 14.1 MeV, a value which is much higher than the threshold energy of the (n, 2n) cross section of uranium isotopes.

  13. Study on the Current Status of Medical Alternative Animal Researches%医学动物替代研究发展现状研究

    Institute of Scientific and Technical Information of China (English)

    卫茂玲

    2016-01-01

    目的:了解我国动物替代研究发展现状,发现问题,提出对策。方法文献检索与定性描述法。以主题、篇名或关键词“动物替代”或“动物减少”或“动物优化”精确检索中文医学常用数据库中国知网、维普数据和万方数据库,补充查找相关研究参考文献。纳入分析组织建设、立法、医学教育和替代研究方法文献,并进行定性描述概括,检索时间截止2015年7月20日。结果初检引文219条,文献发表于1999-2014年,以描述性研究为主。动物替代研究领域包括皮肤刺激、眼刺激毒理学检测、热敏试验和动物模型替代等。替代研究信息交流平台已建立,部分教师已经在实践运用替代原则,相关专著已出版,但法规建设和验证体系滞后,替代研究认识还不乐观,验证方法研究不多。结论国内动物替代研究不多,缺乏系统化建设。未来应加强动物替代研究体系研究,重点在立法、政策引导、医学教育、人才培养和研究方法等。%Objective:To investigate the current status of alternative animal researches in China and thus find the problems and put forward countermeasures. Method: This study was carried out by the methods of literature search and qualitative description. The authors precisely searched the medicine databases commonly used in China ( CNKI, VIP, and Wanfang Data) using the MeSH word, title, or keyword namely"animal alternative","animal decrease" or"animal optimization", and added to find the related researches′references. Then the author included the literature regarding to the organization construction, legislation, medical education, and alternative research methods, and conducted a qualitative description. The deadline was July 20, 2015. Results:There were 219 ini-tial quotations published from 1999 to 2014, and mainly were descriptive researches. The fields of alternative ani-mal researches included skin

  14. Parametric Optimization of Some Critical Operating System Functions--An Alternative Approach to the Study of Operating Systems Design

    Science.gov (United States)

    Sobh, Tarek M.; Tibrewal, Abhilasha

    2006-01-01

    Operating systems theory primarily concentrates on the optimal use of computing resources. This paper presents an alternative approach to teaching and studying operating systems design and concepts by way of parametrically optimizing critical operating system functions. Detailed examples of two critical operating systems functions using the…

  15. Alternative to the Conventional Heating and Cooling Systems in Public Buildings

    OpenAIRE

    Košir, Mitja; Krainer, Aleš; Dovjak, Mateja; Perdan, Rudolf; Kristl, Živa

    2015-01-01

    The paper presents an alternative system for heating and cooling in public buildings. The system was designed for the retrofitted building of the Slovene Ethnographic Museum (SEM) where it was also extensively tested. The installed system includes radiant wall mounted panels for heating and cooling, localized automated tangential fans for cooling and ventilation and a centralized building management system for the regulation and supervision of the performance. The efficiency of the system was...

  16. Nitrogen abatement cost comparison for cropping systems under alternative management choices

    OpenAIRE

    Amon-Armah, Frederick; Yiridoe, Emmanuel K.; Hebb, Dale; Jamieson, Rob

    2013-01-01

    There is a need for cost-effective methods to reduce nitrogen pollution from agriculture. Marginal abatement cost (MAC) curves for nitrate-nitrogen pollution in an agricultural watershed are evaluated using estimated crop yield and nitrate pollution production functions for alternative cropping systems. The cropping systems considered in this study included i) two grain corn-based cropping systems; ii) two potato-based cropping systems; and iii) a vegetable-horticulture system, managed under ...

  17. Comparison of costs for three hypothetical alternative kitchen waste management systems.

    Science.gov (United States)

    Schiettecatte, Wim; Tize, Ronald; De Wever, Heleen

    2014-11-01

    Urban water and waste management continues to be a major challenge, with the Earth's population projected to rise to 9 billion by 2050, with 70% of this population expected to live in cities. A combined treatment of wastewater and the organic fraction of municipal solid waste offers opportunities for improved environmental protection and energy recovery, but the collection and transport of organic wastes must be cost effective. This study compares three alternative kitchen waste collection and transportation systems for a virtual modern urban area with 300,000 residents and a population density of 10,000 persons per square kilometre. Door-to-door collection, being the standard practice in modern urban centres, remains the most economically advantageous at a cost of 263 euros per tonne of kitchen waste. Important drawbacks are the difficult logistics, increased city traffic, air and noise pollution. The quieter, cleaner and more hygienic vacuum transport of kitchen waste comes with a higher cost of 367 euros per tonne, mainly resulting from a higher initial investment cost for the system installation. The third option includes the well-known use of under-sink food waste disposers (often called garbage grinders) that are connected to the kitchen's wastewater piping system, with a total yearly cost of 392 euros per tonne. Important advantages with this system are the clean operation and the current availability of a city-wide sewage conveyance pipeline system. Further research is recommended, for instance the application of a life cycle assessment approach, to more fully compare the advantages and disadvantages of each option. PMID:25341873

  18. Current status of technology development on remote monitoring system

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Wan Ki; Lee, Y. K.; Lee, Y. D.; Na, W. W

    1997-03-01

    IAEA is planning to perform the remote monitoring system in nuclear facility in order to reinforce the economical and efficient inspection. National lab. in U.S. is developing the corresponding core technology and field trial will be done to test the remote monitoring system by considering the case that it replace the current safeguards system. U.S. setup the International Remote Monitoring Project to develop the technology. IAEA makes up remote monitoring team and setup the detail facility to apply remote monitoring system. Therefore, early participation in remote monitoring technology development will make contribution in international remote monitoring system and increase the transparency and confidence in domestic nuclear activities. (author). 12 refs., 20 figs

  19. A high-energy, high-current ion implantation system

    International Nuclear Information System (INIS)

    High current (Pre-Depsup(TM)) ion implanters, operating at 80 keV, have met a need in the semiconductor industry. For certain processes, higher energies are required, either to penetrate a surface layer or to place the dopant ion at a greater depth. The Eaton/Nova Model NV10-160 Pre-Dpsup(TM) Ion Implanter has been developed to meet those special needs. Beam currents as high as 10.0 mA are available at energies up to 160 keV for routine production applications. The system has also been qualified for low current, low dose operation (1011 ions cm-2) and this unique versatility provides the Process and Equipment Engineers with a powerful new tool. The Model NV10-160 also utilizes the Nova-designed, double disk interchange processing system to minimize inactive beam time so that wafer throughputs, up to 300 wafers/h, are achievable on a routine basis. Datalocksup(TM), a computer driven implant monitoring system and AT-4, the Nova cassette-to-cassette wafer loader, are available as standard options. As a production machine, the Model NV10-160 with its high throughput capability, will reduce the implant cost per wafer significantly for doses above 10 x 1015 ions/cm2. Performance patterns are now emerging as some twenty-five systems have now been shipped. This paper summarizes the more important characteristics and reviews the major design features of the NV10-160. (orig.)

  20. A high-energy, high-current ion implantation system

    Science.gov (United States)

    Rose, Peter H.; Faretra, Ronald; Ryding, Geoffery

    1985-01-01

    High current (Pre-DepTM) ion implanters, operating at 80 keV, have met a need in the semiconductor industry. For certain processes, higher energies are required, either to penetrate a surface layer or to place the dopant ion at a greater depth. The Eaton/Nova Model NV10-160 Pre-DepTM Ion Implanter has been developed to meet those special needs. Beam currents as high as 10.0 mA are available at energies up to 160 keV for routine production applications. The system has also been qualified for low current, low dose operation (1011 ions cm-2) and this unique versatility provides the Process and Equipment Engineers with a powerful new tool. The Model NV10-160 also utilizes the Nova-designed, double disk interchange processing system to minimize inactive beam time so that wafer throughputs, up to 300 wafers/h, are achievable on a routine basis. DatalockTM, a computer driven implant monitoring system and AT-4, the Nova cassette-to-cassette wafer loader, are available as standard options. As a production machine, the Model NV10-160 with its high throughput capability, will reduce the implant cost per wafer significantly for doses above 10 × 1015 ions/cm2. Performance patterns are now emerging as some twenty-five systems have now been shipped. This paper summarizes the more important characteristics and reviews the major design features of the NV10-160.

  1. Nuclear proliferation and civilian nuclear power: report of the Nonproliferation Alternative Systems Assessment Program. Volume V. Economics and systems analysis

    International Nuclear Information System (INIS)

    This assessment considers the economics of alternative nuclear reactor and fuel-cycle systems in the light of possible patterns of uranium supply and energy demand, as well as the economic implications of improving the proliferation resistance of the various systems. The assessment focuses on the costs of alternative nuclear technologies and the possible timing of their implementation, based on their economic attractiveness. The objectives of this assessment are to identify when economic incentives to deploy advanced nuclear power systems might exist, to estimate the costs of using technologies that would reduce the risk of proliferation, to assess the impact of major economic uncertainties on the transition to new technologies, and to compare the investments required for alternative systems. This information can then be used to assess the potential economic benefits of alternative research, development, and demonstration programs and the timing of those programs

  2. Intense relativistic electron beam injector system for tokamak current drive

    International Nuclear Information System (INIS)

    We report experimental and theoretical studies of an intense relativistic electron beam (REB) injection system designed for tokamak current drive experiments. The injection system uses a standard high-voltage pulsed REB generator and a magnetically insulated transmission line (MITL) to drive an REB-accelerating diode in plasma. A series of preliminary experiments has been carried out to test the system by injecting REBs into a test chamber with preformed plasma and applied magnetic field. REBs were accelerated from two types of diodes: a conventional vacuum diode with foil anode, and a plasma diode, i.e., an REB cathode immersed in the plasma. REB current was in the range of 50 to 100 kA and REB particle energy ranged from 0.1 to 1.0 MeV. MITL power density exceeded 10 GW/cm2. Performance of the injection system and REB transport properties is documented for plasma densities from 5 x 1012 to 2 x 1014 cm-3. Injection system data are compared with numerical calculations of the performance of the coupled system consisting of the generator, MITL, and diode

  3. New thermodynamical systems. Alternative of compression-absorption; Nouveaux systemes thermodynamiques. Alternative de la compression-absorption

    Energy Technology Data Exchange (ETDEWEB)

    Feidt, M.; Brunin, O.; Lottin, O.; Vidal, J.F. [Universite Henri Poincare Nancy, 54 - Vandoeuvre-les-Nancy (France); Hivet, B. [Electricite de France, 77 - Moret sur Loing (France)

    1996-12-31

    This paper describes a 5 years joint research work carried out by Electricite de France (EdF) and the ESPE group of the LEMTA on compression-absorption heat pumps. It shows how a thermodynamical model of machinery, completed with precise exchanger-reactor models, allows to simulate and dimension (and eventually optimize) the system. A small power prototype has been tested and the first results are analyzed with the help of the models. A real scale experiment in industrial sites is expected in the future. (J.S.) 20 refs.

  4. Modelling the transport system in China and evaluating the current strategies towards the sustainable transport development

    DEFF Research Database (Denmark)

    Liu, W.; Lund, H.; Mathiesen, B.V.

    2013-01-01

    Transport is one of the most challenge sectors when addressing energy security and climate change due to its high reliance on oil products and lack of the alternative fuels. This paper explores the ability of three transport strategies to contribute to the development of a sustainable transport...... in China. With this purpose in mind, a Chinese transport model has been created and three current transport strategies which are high speed railway (HSR), urban rail transit (URT) and electric vehicle (EV) were evaluated together with a reference transport system in 2020. As conservative results, 13...

  5. Cost comparison of the satellite power system and six alternative technologies

    Energy Technology Data Exchange (ETDEWEB)

    Wolsko, T.; Samsa, M.

    1981-04-01

    A framework is described for comparing the Satellite Power System (SPS) with various projected alternative energy sources on the basis of technical possibility, economic viability, and social and environmental acceptability. Each of the following energy sources is briefly described: conventional coal, light water reactor, coal gasification/combined cycle, liquid-metal fast-breeder reactor, central station terrestrial photovoltaic, fusion, and the SPS. The analysis consists of comparison of characterizations, side-by-side analysis, and alternative futures analysis. (LEW)

  6. A magnetospheric magnetic field model with flexible internal current systems

    International Nuclear Information System (INIS)

    A three dimensional B-field model of the Earth's magnetosphere satisfying the condition ∇ · B = 0 is described. Highly flexible ring and cross-tail current systems are combined with the vacuum B-field model of Voigt [1981], a fully shielded dipole within a fixed magnetopause geometry. The ring current consists of nested eastward and westward flowing current distributions which tilt with and remain axially symmetric about the magnetic dipole axis. To include realistic flexing of the current sheet with dipole tilt, the intensity and position of the westward flowing cross-tail current in the midnight meridian can be represented by arbitrary functions of the distance along the magnetotail. Model configurations are completely specified by four initial physical input parameters: the dipole tilt angle, the magnetopause stand-off distance, the geomagnetic index Dst, and the midnight equatorward boundary of the diffuse aurora. These parameters determine the relative position and strength of both the ring and cross-tail currents and provide for a diverse array of configurations including many degrees of magnetotail field stretching. The resulting equatorial flux levels, ΔB profiles, and the dipole tilt-dependent shape and position of the neutral sheet compare well with observations. With additional input parameters, the reconfiguration of the geomagnetic tail during magnetospheric substorms is modeled and incorporated into a magnetic field simulation of an observed substorm event. The ring and cross-tail currents, as prescribed by the set of initial input parameters, follow a physically reasonable sequence of development and magnetic flux densities are in general agreement with geosynchronous observations of the event

  7. Informal Online Decision Making: Current Practices and Support System Design

    OpenAIRE

    André, Paul; Drucker, Steven; schraefel, m.c.

    2007-01-01

    Existing group decision support systems are too complex to support lightweight, informal decision making made popular by the amount of information available on the Web. From an examination of related work, an online survey and a formative study to examine how people currently use the Web for decision support, we present a set of design recommendations towards the development of an informal Web decision support tool.

  8. The TS 600: automatic control system for eddy currents

    International Nuclear Information System (INIS)

    In the scope of fabrication and in service inspection of the PWR steam generator tubing bendle, FRAMATOME developed an automatic Eddy Current testing system: TS600. Based on a mini-computer, TS600 allows to digitize, to store and to process data in various ways, so it is possible to perform several kinds of inspection: conventional inservice inspection, roll area profilometry...... TS600 can also be used to develop new methods of examination

  9. Thermodynamics of currents in nonequilibrium diffusive systems: theory and simulation

    OpenAIRE

    Hurtado, Pablo I.; Espigares, Carlos P.; del Pozo, Jesus J.; Garrido, Pedro L.

    2013-01-01

    Understanding the physics of nonequilibrium systems remains as one of the major challenges of theoretical physics. This problem can be cracked in part by investigating the macroscopic fluctuations of the currents characterizing nonequilibrium behavior, their statistics and associated structures. This fundamental line of research has been severely hampered by the overwhelming complexity of this problem. However, during the last years two new general methods have appeared to investigate fluctua...

  10. Demonstration of a free piston Stirling engine driven linear alternator system. Annual report

    International Nuclear Information System (INIS)

    The objective of the program is to develop a 2 kW Free Piston Stirling Engine/Linear Alternator Energy Conversion System for an isotopic heat source with a greater than 30% overall efficiency. The work was broken up into two phases. Phase I demonstrated the feasibility of the energy conversion system through analysis and experimental testing of the individual components. Phase II is a two-year effort to design, fabricate, and test a prototype demonstrator energy conversion system. The reprt documents the work performed during October 1976 through September 1977, the first year of Phase II. Details of the tasks are presented in five major sections: (1) Linear Alternator Development; (2) Engine/Alternator System Demonstration; (3) Demonstrator Preliminary Design; (4) Demonstrator Detailed Design; and (5) Development of Free Piston Stirling Engine Computer Simulation

  11. Development of the Model of Decision Support for Alternative Choice in the Transportation Transit System

    Directory of Open Access Journals (Sweden)

    Kabashkin Igor

    2015-02-01

    Full Text Available The decision support system is one of the instruments for choosing the most effective decision for cargo owner in constant fluctuated business environment. The objective of this Paper is to suggest the multiple-criteria approach for evaluation and choice the alternatives of cargo transportation in the large scale transportation transit system for the decision makers - cargo owners. The large scale transportation transit system is presented by directed finite graph. Each of 57 alternatives is represented by the set of key performance indicators Kvi and set of parameters Paj. There has been developed a two-level hierarchy system of criteria with ranging expert evaluations based on Analytic Hierarchy Process Method. The best alternatives were suggested according to this method.

  12. Separated feature display system for eddy current inspection data

    International Nuclear Information System (INIS)

    A system is described which organizes the display of analog data on X-Y recorders or storage oscilloscopes. As many as 64 discrete X-Y plots may be displayed in a regular, repeatable 8x8 matrix format. Developed to rapidly display and plot eddy current inspection data from heat exchanger tubes, it may be used on line, but is more efficiently used to transcribe inspection data stored on magnetic tape. The value of the separated feature display system has been extensively demonstrated in field inspections; it generates permanent visible characteristics of anomalies and permits one data analyst to keep up with two inspection teams. (author)

  13. Skewness of steady-state current fluctuations in nonequilibrium systems

    Science.gov (United States)

    Belousov, Roman; Cohen, E. G. D.; Wong, Chun-Shang; Goree, John A.; Feng, Yan

    2016-04-01

    A skewness of the probability for instantaneous current fluctuations, in a nonequilibrium steady state, is observed experimentally in a dusty plasma. This skewness is attributed to the spatial asymmetry, which is imminent to the nonequilibrium systems due to the external hydrodynamic gradient. Using the modern framework of the large deviation theory, we extend the Onsager-Machlup ansatz for equilibrium fluctuations to systems with a preferred spatial direction, and provide a modulated Gaussian probability distribution, which is tested by simulations. This probability distribution is also of potential interest for other statistical disciplines. Connections with the principles of statistical mechanics, due to Boltzmann and Gibbs, are discussed as well.

  14. Research on Low Power Marine Current Power Generation System

    Directory of Open Access Journals (Sweden)

    Dongkai Peng

    2013-09-01

    Full Text Available This study proposes a simple topological structure and power control method for a small scale stand alone marine current system, in which a diode rectifier, DC/DC boost converter for the maximum power control, battery as a storage element and a single phase inverter to link with load. The study establishes the steady-state mathematical model of marine current power generation system and derives the formula between the maximum power point and dc battery voltage. Then use the measurements of DC voltage and DC current to obtain Maximum Power Point Tracking (MPPT by controlling the duty cycle of the boost converter switch in order to simplify the system structure and the control strategies. In this case, the hill climbing searching algorithm is employed to get maximum power point and the double closed loops control strategy is used to improve the dynamic and static performance of single phase inverter. The simulation model is developed in MATLAB/Simulink. And the control method is executed in dSPACE1104 real-time platform. The simulation and experimental results demonstrate the feasibility and validity of the proposed control strategies.

  15. Enhancing the versatility of alternate current biosusceptometry (ACB) through the synthesis of a dextrose-modified tracer and a magnetic muco-adhesive cellulose gel

    International Nuclear Information System (INIS)

    Alternate Current Biosusceptometry (ACB) is a promising bio-magnetic method, radiation free and easily performed used for gastric emptying exams. Due to development on its sensitivity level, interesting nature, noninvasiveness and low cost it has attracted a lot of attention. In this work, magnetic nanoparticles of Mn–Zn ferrite as well as dextrose-modified nanoparticles were synthesized to be used as possible tracers in ACB gastric emptying exams. In addition, a magnetic muco-adhesive gel was obtained by modifying the ferrite nanoparticles with cellulose. Based on in-vivo tests in rats, we show that the pure ferrite nanoparticles, whose isoelectric point was found to be at pH = 3.2, present a great sensitivity to pH variations along the gastrointestinal tract, while the reduction of the isoelectric point by the dextrose modification leads to suitable nanoparticles for rapid gastric emptying examinations. On the other hand, the in-vivo tests show that the muco-adhesive cellulose gel presents substantial stomach adhesion and is a potential drug delivery system easily traceable by the ACB system

  16. Enhancing the versatility of alternate current biosusceptometry (ACB) through the synthesis of a dextrose-modified tracer and a magnetic muco-adhesive cellulose gel

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Murillo L., E-mail: murillolongo@gmail.com [Niels Bohr Institute, University of Copenhagen, DK-2100 Copenhagen (Denmark); Instituto de Biociências, Universidade Estadual Paulista, CP 510, 18618–970 Botucatu SP (Brazil); Calabresi, Marcos F.; Quini, Caio; Matos, Juliana F.; Miranda, José R.A.; Saeki, Margarida J. [Instituto de Biociências, Universidade Estadual Paulista, CP 510, 18618–970 Botucatu SP (Brazil); Bordallo, Heloisa N. [Niels Bohr Institute, University of Copenhagen, DK-2100 Copenhagen (Denmark)

    2015-03-01

    Alternate Current Biosusceptometry (ACB) is a promising bio-magnetic method, radiation free and easily performed used for gastric emptying exams. Due to development on its sensitivity level, interesting nature, noninvasiveness and low cost it has attracted a lot of attention. In this work, magnetic nanoparticles of Mn–Zn ferrite as well as dextrose-modified nanoparticles were synthesized to be used as possible tracers in ACB gastric emptying exams. In addition, a magnetic muco-adhesive gel was obtained by modifying the ferrite nanoparticles with cellulose. Based on in-vivo tests in rats, we show that the pure ferrite nanoparticles, whose isoelectric point was found to be at pH = 3.2, present a great sensitivity to pH variations along the gastrointestinal tract, while the reduction of the isoelectric point by the dextrose modification leads to suitable nanoparticles for rapid gastric emptying examinations. On the other hand, the in-vivo tests show that the muco-adhesive cellulose gel presents substantial stomach adhesion and is a potential drug delivery system easily traceable by the ACB system.

  17. Technical Evaluation Report 24: Open Source Software: an alternative to costly Learning Management Systems

    Directory of Open Access Journals (Sweden)

    Jim Depow

    2003-10-01

    Full Text Available This is the first in a series of two reports discussing the use of open source software (OSS and free software (FS in online education as an alternative to expensive proprietary software. It details the steps taken in a Canadian community college to download and install the Linux Operating System in order to support an OSS/ FS learning management system (LMS.

  18. What Can We Learn from Chaos Theory? An Alternative Approach to Instructional Systems Design.

    Science.gov (United States)

    You, Yeongmahn

    1993-01-01

    Explains chaos theory; compares a conventional instructional systems design (ISD) approach with chaos theory and dynamic nonlinear systems, including deterministic predictability and indeterministic unpredictability and negative and positive feedback; explores theoretical implications for developing an alternative ISD model; and recommends future…

  19. Economic performance of alternative tillage systems in the northern Corn Belt

    Science.gov (United States)

    While no-till (NT) cropping systems can provide conservation benefits in the northern Corn Belt, adoption has been low due to concerns about potential yield reductions and economic risk. Strip-tillage (ST) systems have been proposed as an alternative that may provide many of the conservation benefit...

  20. Medical telerobotic systems: current status and future trends.

    Science.gov (United States)

    Avgousti, Sotiris; Christoforou, Eftychios G; Panayides, Andreas S; Voskarides, Sotos; Novales, Cyril; Nouaille, Laurence; Pattichis, Constantinos S; Vieyres, Pierre

    2016-01-01

    Teleoperated medical robotic systems allow procedures such as surgeries, treatments, and diagnoses to be conducted across short or long distances while utilizing wired and/or wireless communication networks. This study presents a systematic review of the relevant literature between the years 2004 and 2015, focusing on medical teleoperated robotic systems which have witnessed tremendous growth over the examined period. A thorough insight of telerobotics systems discussing design concepts, enabling technologies (namely robotic manipulation, telecommunications, and vision systems), and potential applications in clinical practice is provided, while existing limitations and future trends are also highlighted. A representative paradigm of the short-distance case is the da Vinci Surgical System which is described in order to highlight relevant issues. The long-distance telerobotics concept is exemplified through a case study on diagnostic ultrasound scanning. Moreover, the present review provides a classification into short- and long-distance telerobotic systems, depending on the distance from which they are operated. Telerobotic systems are further categorized with respect to their application field. For the reviewed systems are also examined their engineering characteristics and the employed robotics technology. The current status of the field, its significance, the potential, as well as the challenges that lie ahead are thoroughly discussed. PMID:27520552

  1. Assessment of the impacts of spent fuel disassembly alternatives on the Nuclear Waste Isolation System

    International Nuclear Information System (INIS)

    The objective of this report was to evaluate four possible alternative methods of preparing and packaging spent fuel assemblies for geologic disposal against the Reference Process of unmodified spent fuel. The four alternative processes were: (1) End fitting removal, (2) Fission gas venting and resealing, (3) Fuel bundle disassembly and close packing of fuel pins, and (4) Fuel shearing and immobilization. Systems analysis was used to develop a basis of comparison of the alternatives. Conceptual processes and facility layouts were devised for each of the alternatives, based on technology deemed feasible for the purpose. Assessments were made of 15 principal attributes from the technical, operational, safety/risk, and economic considerations related to each of the alternatives, including both the surface packaging and underground repository operations. Specific attributes of the alternative processes were evaluated by assigning a number for each that expressed its merit relative to the corresponding attribute of the Reference Process. Each alternative process was then ranked by summing the numbers for attributes in each of the four assessment areas and collectively. Fuel bundle disassembly and close packing of fuel pins was ranked the preferred method of disposal of spent fuel. 63 references, 46 figures, 46 tables

  2. 77 FR 67348 - Privacy Act of 1974; System of Records-Alternative Dispute Resolution (ADR) Center Case Tracking...

    Science.gov (United States)

    2012-11-09

    ... Privacy Act of 1974; System of Records--Alternative Dispute Resolution (ADR) Center Case Tracking System AGENCY: Office of Management (OM), Alternative Dispute Resolution Center, Department of Education. ACTION... Resolution Center'' (IDR Center) (18-05-12), including revising the title to ``Alternative Dispute...

  3. Technology assessment of disposal alternatives to determine a reference geological repository system for HLW

    International Nuclear Information System (INIS)

    This study is to determine the most promising alternative, that will be developed further as a reference HLW repository system, by comparing the 7 alternatives that were proposed based on the spent fuel packaging options concerning the characteristics of spent PWR and CANDU fuel generated from the domestic NPP and the waste package arrangements and repository layout options. It should be determined by comparing the proposed alternatives from the aspects of technology, safety and economics. In this study, however, the comparison of alternatives was just based on the technology assessment because of the lack of the relevant information. The comparison criteria includes the degree of difficulty, development and maturity of the technology to be applied in repository system construction, operation, retrieval, etc. and the safety during the repository construction and operation. Based on such comparison criteria, the alternative comparison study was performed by a typical pair-wise comparison method. The result showed that, from the aspect of the construction, vertical emplacement options ranked high so that HSA and HCop ranked first and second, respectively. On the other hand, from the aspect of operation, the vertical emplacement options ranked high and VSA and VAT were ranked first and second. Depending upon the degree of importance of construction and operation of the repository, the final results of the alternatives comparison could be changed. (author). 19 refs., 6 tabs., 13 figs

  4. High-energy, high-current ion implantation system

    Energy Technology Data Exchange (ETDEWEB)

    Rose, P.H.; Faretra, R.; Ryding, G. (Eaton Corp., Beverly, MA (USA). Ion Beam Systems Div.)

    1985-01-01

    High current (Pre-Depsup(TM)) ion implanters, operating at 80 keV, have met a need in the semiconductor industry. For certain processes, higher energies are required, either to penetrate a surface layer or to place the dopant ion at a greater depth. The Eaton/Nova Model NV10-160 Pre-Dpsup(TM) Ion Implanter has been developed to meet those special needs. Beam currents as high as 10.0 mA are available at energies up to 160 keV for routine production applications. The system has also been qualified for low current, low dose operation (10/sup 11/ ions cm/sup -2/) and this unique versatility provides the Process and Equipment Engineers with a powerful new tool. The Model NV10-160 also utilizes the Nova-designed, double disk interchange processing system to minimize inactive beam time so that wafer throughputs, up to 300 wafers/h, are achievable on a routine basis. Datalocksup(TM), a computer driven implant monitoring system and AT-4, the Nova cassette-to-cassette wafer loader, are available as standard options. As a production machine, the Model NV10-160 with its high throughput capability, will reduce the implant cost per wafer significantly for doses above 10 x 10/sup 15/ ions/cm/sup 2/. Performance patterns are now emerging as some twenty-five systems have now been shipped. This paper summarizes the more important characteristics and reviews the major design features of the NV10-160.

  5. Characteristics of the terrestrial field-aligned current system

    Directory of Open Access Journals (Sweden)

    J. W. Gjerloev

    2011-10-01

    Full Text Available We present the first ever comprehensive statistical study of the spatiotemporal characteristics of field-aligned currents in the terrestrial magnetosphere-ionosphere system using multi point measurements. We determine how the FAC density, variability and scale size are coupled. The three ST 5 satellites were in a pearls-on-a-string formation making measurements of the magnetic field with variable inter-spacecraft separations ranging from a few seconds to about 10 min. More than 4700 sets of satellite passes are analyzed using a robust correlation analysis aimed at determining the variability of the FAC system as a function of scale size and satellite spacing. We find significant differences between the FAC characteristics on the dayside and on the nightside in terms of dynamics of the current systems. On the dayside the FAC characteristics are found to be independent of IMF Bz and geomagnetic activity while the nightside indicates increased variability during disturbed conditions. The boundary separating highly and poorly correlated FACs can be fitted by a linear line for satellite separations shorter than 60 s (dayside and 160 s (nightside. We interpret this as the dayside and nightside magnetospheric reconfiguration times respectively. For times exceeding this the FAC characteristics are suggested to be controlled by the solar wind (dayside and plasma sheet (nightside dynamics. Finally, the characteristics of FAC system with scale sizes larger than ~200 km (at ionospheric altitude appear to be stable and repeatable on time scales of the order of a minute (i.e. comparable to the low-altitude orbiting satellite's traverse time across the auroral belt. In this sense, our results effectively validate the Iijima and Potemra (1978 assumption that on average the large-scale currents with scale sizes of the Region1 and Region2 are quasi-persistently significant in the transport of energy and momentum between the magnetosphere and the

  6. The Current State and Perspectives of Systems Biology

    Institute of Scientific and Technical Information of China (English)

    Tielui Shi; Yixue Li

    2006-01-01

    Emerging as a new field in biology recently, Systems Biology provides a branch new way to study the biological activities in organisms. In order to decode the complexity of life systematically,systems biology integrates the "-omics" and uses the high throughput methods from transcriptomics,protomics and metabonomics to detect the dynamic activities in cell; and then, it incorporates bioinformatics methods to integrate and analyze those data, and simulate the biological processes based on the model built from those integrated data. In this paper, the current state, the research field and the methods for the Systems Biology are introduced briefly, and then, several ideas about future development in this field are also proposed.

  7. Investigation of parameters of the three phase high-voltage alternating current plasma generator with power up to 100 kW working on steam

    Science.gov (United States)

    Rutberg, Ph G.; Lukyanov, S. A.; Kiselev, A. A.; Kuschev, S. A.; Nakonechny, Gh V.; Nikonov, A. V.; Popov, S. D.; Serba, E. O.; Spodobin, V. A.; Surov, A. V.

    2011-01-01

    The paper presents the results of experimental investigation of parameters of the three-phase high voltage alternating current plasma generator with power up to 100 kW operating on steam with gas protection of the electrodes. Researches were carried out over a range of arc current from 25 to 50 A and range of steam consumption of 3-5 g/s. Current-voltage and volt consumable characteristics, operation oscillograms and dependence of power versus the flow rate of steam and protective gas are presented.

  8. Alternative splicing at C terminus of Ca(V)1.4 calcium channel modulates calcium-dependent inactivation, activation potential, and current density.

    Science.gov (United States)

    Tan, Gregory Ming Yeong; Yu, Dejie; Wang, Juejin; Soong, Tuck Wah

    2012-01-01

    The Ca(V)1.4 voltage-gated calcium channel is predominantly expressed in the retina, and mutations to this channel have been associated with human congenital stationary night blindness type-2. The L-type Ca(V)1.4 channel displays distinct properties such as absence of calcium-dependent inactivation (CDI) and slow voltage-dependent inactivation (VDI) due to the presence of an autoinhibitory domain (inhibitor of CDI) in the distal C terminus. We hypothesized that native Ca(V)1.4 is subjected to extensive alternative splicing, much like the other voltage-gated calcium channels, and employed the transcript scanning method to identify alternatively spliced exons within the Ca(V)1.4 transcripts isolated from the human retina. In total, we identified 19 alternative splice variations, of which 16 variations have not been previously reported. Characterization of the C terminus alternatively spliced exons using whole-cell patch clamp electrophysiology revealed a splice variant that exhibits robust CDI. This splice variant arose from the splicing of a novel alternate exon (43*) that can be found in 13.6% of the full-length transcripts screened. Inclusion of exon 43* inserts a stop codon that truncates half the C terminus. The Ca(V)1.4 43* channel exhibited robust CDI, a larger current density, a hyperpolarized shift in activation potential by ∼10 mV, and a slower VDI. Through deletional experiments, we showed that the inhibitor of CDI was responsible for modulating channel activation and VDI, in addition to CDI. Calcium currents in the photoreceptors were observed to exhibit CDI and are more negatively activated as compared with currents elicited from heterologously expressed full-length Ca(V)1.4. Naturally occurring alternative splice variants may in part contribute to the properties of the native Ca(V)1.4 channels. PMID:22069316

  9. Nuclear proliferation and civilian nuclear power. Report of the Nonproliferation Alternative Systems Assessment Program. Volume VII. International perspectives

    International Nuclear Information System (INIS)

    The purpose of this volume is to assess the proliferation vulnerabilities of the present deployment of civilian nuclear-power systems within the current nonproliferation regime and, in light of their prospective deployment, to consider technical and institutional measures and alternatives which may contribute to an improved regime in which nuclear power could play a significant part. An assessment of these measures must include consideration of their nonproliferation effectiveness as well as their bearing upon energy security, and their operational, economic, and political implications. The nature of these considerations can provide some measure of their likely acceptability to various nations

  10. Army Gas-Cooled Reactor Systems program: alternator final design report

    Energy Technology Data Exchange (ETDEWEB)

    1964-06-01

    The development and testing of a demonstration brushless alternator for the ML-1 mobile nuclear power plant is described. The brushless concept was selected after it became apparent that a conventional power generator could not satisfy the ML-1 weight and size requirements. The demonstration alternator fabricated and tested under this program did not meet all performance specifications; the efficiency was low and the unit could not be operated for significant periods of time without overheating. However, a large body of useful data was accumulated during the extensive development program. Of special interest are data on the rotor and stator design, the cooling requirements and on the distribution of eddy current losses. Analysis of the data indicates that a brushless alternator, only slightly larger and heavier than was specified for the ML-1, could be developed with a modest additional effort.

  11. Comparing current cluster, massively parallel, and accelerated systems

    Energy Technology Data Exchange (ETDEWEB)

    Barker, Kevin J [Los Alamos National Laboratory; Davis, Kei [Los Alamos National Laboratory; Hoisie, Adolfy [Los Alamos National Laboratory; Kerbyson, Darren J [Los Alamos National Laboratory; Pakin, Scott [Los Alamos National Laboratory; Lang, Mike [Los Alamos National Laboratory; Sancho Pitarch, Jose C [Los Alamos National Laboratory

    2010-01-01

    Currently there is large architectural diversity in high perfonnance computing systems. They include 'commodity' cluster systems that optimize per-node performance for small jobs, massively parallel processors (MPPs) that optimize aggregate perfonnance for large jobs, and accelerated systems that optimize both per-node and aggregate performance but only for applications custom-designed to take advantage of such systems. Because of these dissimilarities, meaningful comparisons of achievable performance are not straightforward. In this work we utilize a methodology that combines both empirical analysis and performance modeling to compare clusters (represented by a 4,352-core IB cluster), MPPs (represented by a 147,456-core BG/P), and accelerated systems (represented by the 129,600-core Roadrunner) across a workload of four applications. Strengths of our approach include the ability to compare architectures - as opposed to specific implementations of an architecture - attribute each application's performance bottlenecks to characteristics unique to each system, and to explore performance scenarios in advance of their availability for measurement. Our analysis illustrates that application performance is essentially unrelated to relative peak performance but that application performance can be both predicted and explained using modeling.

  12. Architecture and control of a high current ion implanter system

    International Nuclear Information System (INIS)

    The design of an ion implant system for use in production requires that special attention be given to areas of design which normally are not emphasized on research or development type ion implanters. Manually operated, local controls are replaced by remote controls, automatic sequencing, and digital displays. For ease of maintenance and replication the individual components are designed as simply as possible and are contained in modules of separate identities, joined only by the beam line and electrical interconnections. A production environment also imposes requirements for the control of contamination and maintainability of clean room integrity. For that reason the major portion of the hardware is separated from the clean operator area and is housed in a maintenance core area. The controls of a production system should also be such that relatively unskilled technicians are able to operate the system with optimum repeatability and minimum operator intervention. An extensive interlock system is required. Most important, for use in production the ion implant system has to have a relatively high rate of throughput. Since the rate of throughput at a given dose is a function of beam current, pumpdown time and wafer handling capacity, design of components affecting these parameters has been optimized. Details of the system are given. (U.K.)

  13. A Power Supply System with ZVS and Current-Doubler Features for Hybrid Renewable Energy Conversion

    Directory of Open Access Journals (Sweden)

    Jye-Chau Su

    2013-09-01

    Full Text Available In this paper, a power supply system for hybrid renewable energy conversion is proposed, which can process PV (photovoltaic power and wind-turbine energy simultaneously for step-down voltage and high current applications. It is a dual-input converter and mainly contains a PV energy source, a wind turbine energy source, a zero-voltage-switching (ZVS forward converter, and a current-doubler rectifier. The proposed power supply system has the following advantages: (1 PV-arrays and wind-energy sources can alternatively deliver power to the load during climate or season alteration; (2 maximum power point tracking (MPPT can be accomplished for both different kinds of renewable-energy sources; (3 ZVS and synchronous rectification techniques for the active switches of the forward converter are embedded so as to reduce switching and conducting losses; and (4 electricity isolation is naturally obtained. To achieve an optimally dynamic response and to increase control flexibility, a digital signal processor (DSP is investigated and presented to implement MPPT algorithm and power regulating scheme. Finally, a 240 W prototype power supply system with ZVS and current-doubler features to deal with PV power and wind energy is built and implemented. Experimental results are presented to verify the performance and the feasibility of the proposed power supply system.

  14. Alternate Data Acquisition and Real-time Monitoring System on HT-7 Tokamak

    Institute of Scientific and Technical Information of China (English)

    Wei Peijie; Luo Jiarong; Wang Hua; Li Guiming

    2005-01-01

    A new system called alternate data acquisition and real-time monitoring system has been developed for long-time discharge in tokamak operation. It can support continuous on-line data acquisition at a high sampling rate and a graphic display of the plasma parameters during the discharge. Thus operators can monitor and control the plasma state in real time. An application of this system has been demonstrated on the HT-7 tokamak.

  15. Researching alternative, sustainable agricultural systems: A modelling approach by examples from Denmark

    OpenAIRE

    Alrøe, Hugo Fjelsted; Kristensen, Erik Steen

    2000-01-01

    In recent decades agriculture has undergone rapid technological and structural changes. This development has raised concerns about the sustainability of modern agriculture and motivated an interest in alternative and, perhaps, more sustainable agricultural systems. Agriculture involves both ecological and social systems, and research in agricultural systems therefore faces the dual challenge of understanding complex agro-ecosystem interactions and handling the involvement of human actors, the...

  16. Current approach for urinary system stone disease in pregnant women

    Directory of Open Access Journals (Sweden)

    Orcun Celik

    2016-01-01

    Full Text Available Urinary system stones can be classified according to size, location, X-ray characteristics, aetiology of formation, composition, and risk of recurrence. Especially urolithiasis during pregnancy is a diagnostic and therapeutic challenge. In most cases, it becomes symptomatic in the second or third trimester. Diagnostic options in pregnant women are limited due to the possible teratogenic, carcinogenic, and mutagenic risk of foetal radiation exposure. Clinical management of a pregnant urolithiasis patient is complex and demands close collaboration between patient, obstetrician and urologist. We would like to review current diagnosis and treatment modalities of stone disease of pregnant woman.

  17. Seasonal Variability in the Kuroshio Extension Current System

    Institute of Scientific and Technical Information of China (English)

    LAN Jian; XU Long; GUO Peifang

    2003-01-01

    Based on the GDEM hydrographic data with a resolution of 0.5°× 0.5°, the current system (Kuroshio south of Japan and Kuroshio Extension east of Japan) is determined by using the P-Vector Method, and its seasonal variability is investigated. The Kuroshio Meander south of Japan, the two lee-wave meanders in the Kuroshio Extension and the bifurcation of the Kuroshio Extension are properly presented. The path of the Kuroshio Meander, the position of the second (east) meander in the Kuroshio Extension and the bifurcation of the Kuroshio Extension display evident seasonal variation.

  18. An evaluation of current EIA system in Pakistan

    International Nuclear Information System (INIS)

    The challenge of reducing poverty and increasing economic growth has often led Pakistan to overlook environmental sustainability. Consequently, Pakistan, is suffering from severe environmental problems. This has spurred an increasing demand for and effective Environmental Impact Assessment (EIA) System with environmental management tools and techniques that can help the country to adequately diagnose their risks and suggest mitigation options. In the past few years Pakistan has begun implementing EIA' s as a preventive tool. However, given the judiciary, institutional and structural predicament, the outcome of the EIA process has resulted in great disparities. Given the growing regional environmental problems it is now a priority to seek an effective EIA systems, principles, and procedures in the country. This paper seeks to distinguish the Pakistan EIA strengths and weaknesses; it also focuses on identifying common positive and negative characteristics of the Pakistan EIA system. Furthermore, differences between the interested parties of the EIA system in the country were evaluated via a survey to ensure a good understanding of the factors of a comprehensive and effective EIA system. Analytical comparisons were made among the different interested parties of the EIA system in Pakistan. Statistical methods were used to analyze the data received and recommendations were made based on the outcome of the data results. These results will assist: (i) Pakistan to improve its EIA system (ii) other South Asian countries which may have a similar EIA systems in developing policy, planning and reforms and (iii) International organizations that work or invest in the region to enhance the attainment of environ- mental protection objectives on a broader, more cost effective, and realistic scale than current practices. (author)

  19. Alternative current conduction mechanisms of organic-inorganic compound [N(CH3)3H]2ZnCl4

    Science.gov (United States)

    Ben Bechir, M.; Karoui, K.; Tabellout, M.; Guidara, K.; Ben Rhaiem, A.

    2014-04-01

    [N(CH3)3H]2ZnCl4 has been studied by X-ray powder diffraction patterns, differential scanning calorimetry (DSC), and impedance spectroscopy. The [N(CH3)3H]2ZnCl4 hybrid compound is crystallized at room temperature (T ≈ 300 K) in the orthorhombic system with Pnma space group. Five phase transitions (T1 = 255 K, T2 = 282 K, T3 = 302 K, T4 = 320 K, and T5 = 346 K) have been proved by DSC measurements. The electrical technique was measured in the 10-1-107 Hz frequency range and 233-363 K temperature interval. The frequency dependence of alternative current (AC) conductivity is interpreted in terms of Jonscher's law. The AC electrical conduction in [N(CH3)3H]2ZnCl4 is analyzed by different processes, which can be attributed to several models: the correlated barrier hopping model in phase I, the overlapping large polaron tunneling model in phase II, the quantum mechanical tunneling model in phase IV, and the non-overlapping small polaron tunneling model in phases III, V, and VI. The conduction mechanism is studied with the help of Elliot's theory, and the Elliot's parameters are determined.

  20. Comments on Current Space Systems Observing the Climate

    Science.gov (United States)

    Fisk, L. A.

    2016-07-01

    The Global Climate Observing System (GCOS), which was established in 1992, has been effective in specifying the observations needed for climate studies, and advocating that these observations be made. As a result, there are essential climate variables being observed, particularly from space, and these have formed the basis for our ever-improving models of how the Earth system functions and the human impact on it. We cannot conclude, however, that the current observing system in space is adequate. Climate change is accelerating, and we need to ensure that our observations capture, with completeness and with proper resolution and cadence, the most important changes. Perhaps of most significance, we need to use observations from space to guide the mitigation and adaptation strategies on which at last our civilization seems prepared to embark. And we need to use our observations to educate particularly policy makers on the reality of climate change, so that none deny the need to act. COSPAR is determined to play its part in highlighting the need to strengthen the climate observing system and notably its research component. This is being accomplished through events like the present roundtable, through the work of its Scientific Commission A, its Task Group on GEO (where COSPAR is serving as a member of its Program Board), and by promoting among space agencies and policy-makers the recently released scientific roadmap on Integrated Earth System Science for the period 2016-2025.

  1. System performance characteristics of superconducting alternators for electric utility power generation

    International Nuclear Information System (INIS)

    This paper reviews the reasons for the low synchronous reactance attributable to the use of superconducting field winding, and compares the expected performance characteristics of a superconducting alternator in the 1000 MVA range with those of a conventional power system generator of comparable rating. Among the specific topics discussed are performance with regard to dynamic stability, transient stability, voltage regulation, and excitation control. The principal operational advantages of a superconducting alternator appear to be (1) the absence of a dynamic stability limit within its MVA capability, (2) significantly greater transient stability when operating at leading power factors, (3) superior voltage regulation, and (4) no degradation of dynamic stability due to automatic voltage regulator action. Consequently, superconducting alternators appear to be ideally matched to modern power system applications that require operation of generators at leading power factors. (U.S.)

  2. Alternative Drive Systems as a Part of a GHG Emission Reduction

    Directory of Open Access Journals (Sweden)

    Jevto Lučić

    2011-09-01

    Full Text Available Air pollution as a consequence of a modern way of life contaminates the natural environment and brings us the global warming which poses a clear and present danger to civilization. The main causes of global warming are greenhouse gasses, which arise of reliance on fossil fuels, deforestation, agriculture, industrial processes and transport. The transport itself makes 14% of the main causes of greenhouse gasses. Its dependence on fossil fuels, together with the decrease of a world fossil fuels reserves, force us to look for alternative fuels and to develop alternative drive systems, which can stabilize and reduce the greenhouse effect, and at the same time offer us new technologies, independent on a fossil fuels. This paper will try to present potential solutions for this problem, and to show the development of alternative drive systems

  3. Request for plot approval: Final leakage current measurements with HVPP4-Current Monitor System for 2011 - 2012

    CERN Document Server

    Wang, R; The ATLAS collaboration; Girolamo, B; Gorelov, I; Hoeferkamp, M; Kersten, S; Kovalenko, S; Lantzsch, K; Metcalfe, J; Muenstermann, D; Boyd, G; Skubic, P; Sicho, P; Toms, K; Seidel, S

    2014-01-01

    Final leakage current measurements with HVPP4-Current Monitor System for full 2011 - 2012 data taking. The results are in good agreement with the Hamburg model for all three Layers. The dependence of the leakage current on #eta and #phi has been studied.

  4. Ionospheric heating, upwelling, and depletions in auroral current systems

    Science.gov (United States)

    Zettergren, M. D.; Semeter, J. L.

    2010-12-01

    This research investigates aspects of ionospheric dynamics relevant to magnetosphere-ionosphere coupling in auroral arc current systems. Auroral electric fields and particle precipitation deposit energy in the ionosphere, often resulting in enhanced ion or electron temperatures. This heating has a wide variety of consequences for the ionosphere. High ion temperatures alter chemical balance in the lower F-region, resulting in conversion to a molecular ion plasma, faster recombination, and plasma depletions. Pressure enhancements resulting from both ion and electron heating are capable of generating intense ion upflows. Ion upflow and depletion processes redistribute and structure the auroral plasma in ways that are likely of consequence to wave coupling of the magnetosphere and ionosphere. These implications are examined through the use of a fluid-kinetic model of the auroral ionosphere and new incoherent scatter radar data analysis techniques. Results indicate that enhanced recombination of molecular ions in auroral downward current regions may work in concert with well-known electrodynamic depletion processes, in the F-region ionosphere. Furthermore, ionospheric upflows in auroral upward and downward current regions may be quite different in terms of intensity and types of upflowing ions.

  5. A compact analytical formalism for current transients in electrochemical systems

    CERN Document Server

    Nair, Pradeep R

    2011-01-01

    Micro and nanostructured electrodes form an integral part of a wide variety of electrochemical systems for biomolecule detection, batteries, solar cells, scanning electrochemical microscopy, etc. Given the complexity of the electrode structures, the Butler-Volmer formalism of redox reactions, and the diffusion transport of redox species, it is hardly surprising that only a few problems are amenable to closed form, compact analytical solutions. While numerical solutions are widely used, it is often difficult to integrate the insights gained to the design and optimization of electrochemical systems. In this article, we develop a comprehensive analytical formalism for current transients that not only anticipate the response of complex electrode structures to complicated voltammetry measurements, but also intuitively interpret diverse experiments such as redox detection of molecules at nanogap electrodes, scanning electrochemical microscopy, etc. The results from the analytical model, well supported through detai...

  6. CURRENT TRENDS IN β-CYCLODEXTRIN BASED DRUG DELIVERY SYSTEMS

    Directory of Open Access Journals (Sweden)

    Lala Rita

    2011-05-01

    Full Text Available Many compounds identified through various screening programs are poorly soluble in the water. These molecules are difficult to formulate using the conventional formulation approaches. An important tool in this regard is the use of cyclodextrins, especially chemically modified cyclodextrins. These starch derivatives interact via dynamic complex formation and other mechanisms in a way that camouflages undesirable physicochemical properties, including low aqueous solubility, poor dissolution rate and limited drug stability, which leads to additional benefits such as increased solubility, increased bioavaibility, protection of active molecules from physicochemical degradation and decreased side-effects. This review aims to assess the use of cyclodextrins in newer drug delivery systems such as nanosponges, nanoparticles, nanospheres, nanoassemblies, drug-in cyclodextrin-in deformable liposomes and other drug delivery systems. These approaches are useful for resolving many of the current issues associated with developing and commercializing poorly water soluble drugs.

  7. Statistical detection model for eddy-current systems

    International Nuclear Information System (INIS)

    This chapter presents a detailed analysis of some measured noise data and the results of using those data with a probe-flaw interaction model to compute the surface-crack detection characteristics of two different air-core coil probes. The objective is to develop a statistical model for determining the probability of detecting a given flaw using an eddy-current system. The basis for developing a statistical detection model is a measurement model that relates the output voltage of the system to its various signal and noise components. Topics considered include statistics of the measured background voltage, calibration of the probe-flaw interaction model and signal-to-noise ratio (SNR) definition, the operating characteristic, and a comparison of air-core probes

  8. Differential distributions of Synechococcus subgroups across the California Current System.

    Directory of Open Access Journals (Sweden)

    RyanWilliamPaerl

    2011-04-01

    Full Text Available Synechococcus is an abundant marine cyanobacterial genus composed of different populations that vary physiologically. Synechococcus narB gene sequences (encoding for nitrate reductase in cyanobacteria obtained previously from isolates and the environment (e.g. North Pacific Gyre Station ALOHA, Hawaii or Monterey Bay, California were used to develop quantitative PCR (qPCR assays. These qPCR assays were used to quantify populations from specific narB phylogenetic clades across the California Current System (CCS, a region composed of dynamic zones between a coastal-upwelling zone and the oligotrophic Pacific Ocean. Targeted populations (narB subgroups had different biogeographic patterns across the CCS, which appear to be driven by environmental conditions. Subgroups C_C1, D_C1 and D_C2 were abundant in coastal-upwelling to coastal-transition zone waters with relatively high to intermediate ammonium, nitrate and chl. a concentrations. Subgroups A_C1 and F_C1 were most abundant in coastal-transition zone waters with intermediate nutrient concentrations. E_O1 and G_O1 were most abundant at different depths of oligotrophic open-ocean waters (either in the upper mixed layer or just below. E_O1, A_C1 and F_C1 distributions differed from other narB subgroups and likely possess unique ecologies enabling them to be most abundant in waters between coastal and open-ocean waters. Different CCS zones possessed distinct Synechococcus communities. Core California Current (CC water possessed low numbers of narB subgroups relative to counted Synechococcus cells, and coastal-transition waters contained high abundances of Synechococcus cells and total number of narB subgroups. The presented biogeographic data provides insight on the distributions and ecologies of Synechococcus present in an eastern boundary current system.

  9. A Hydraulic Motor-Alternator System for Ocean-Submersible Vehicles

    Science.gov (United States)

    Aintablian, Harry O.; Valdez, Thomas I.; Jones, Jack A.

    2012-01-01

    An ocean-submersible vehicle has been developed at JPL that moves back and forth between sea level and a depth of a few hundred meters. A liquid volumetric change at a pressure of 70 bars is created by means of thermal phase change. During vehicle ascent, the phase-change material (PCM) is melted by the circulation of warm water and thus pressure is increased. During vehicle descent, the PCM is cooled resulting in reduced pressure. This pressure change is used to generate electric power by means of a hydraulic pump that drives a permanent magnet (PM) alternator. The output energy of the alternator is stored in a rechargeable battery that powers an on-board computer, instrumentation and other peripherals.The focus of this paper is the performance evaluation of a specific hydraulic motor-alternator system. Experimental and theoretical efficiency data of the hydraulic motor and the alternator are presented. The results are used to evaluate the optimization of the hydraulic motor-alternator system. The integrated submersible vehicle was successfully operated in the Pacific Ocean near Hawaii. A brief overview of the actual test results is presented.

  10. Science, Systems, and Theoretical Alternatives in Educational Administration: The Road Less Travelled

    Science.gov (United States)

    Evers, Colin W.; Lakomski, Gabriele

    2012-01-01

    Purpose: The purpose of this paper is to offer a critical reflection on ideas that have been published in the "Journal of Educational Administration" over the last 50 years that present perspectives on the nature of educational administration and its various aspects, that are alternatives to the mainstream systems-scientific view of educational…

  11. Modeling of a sedimentary rock alternative for the siting of the radioactive waste disposal system

    International Nuclear Information System (INIS)

    Here are described the main concepts, the approximations, and all those simulation aspects that characterize the modeling performed using the unsaturated saturated approach for porous media. The objective of this work is to obtain a generic description of a sedimentary rock soil as an alternative site for the low and intermediate level radioactive waste disposal system. (author)

  12. Waste management system alternatives for treatment of wastes from spent fuel reprocessing

    International Nuclear Information System (INIS)

    This study was performed to help identify a preferred TRU waste treatment alternative for reprocessing wastes with respect to waste form performance in a geologic repository, near-term waste management system risks, and minimum waste management system costs. The results were intended for use in developing TRU waste acceptance requirements that may be needed to meet regulatory requirements for disposal of TRU wastes in a geologic repository. The waste management system components included in this analysis are waste treatment and packaging, transportation, and disposal. The major features of the TRU waste treatment alternatives examined here include: (1) packaging (as-produced) without treatment (PWOT); (2) compaction of hulls and other compactable wastes; (3) incineration of combustibles with cementation of the ash plus compaction of hulls and filters; (4) melting of hulls and failed equipment plus incineration of combustibles with vitrification of the ash along with the HLW; (5a) decontamination of hulls and failed equipment to produce LLW plus incineration and incorporation of ash and other inert wastes into HLW glass; and (5b) variation of this fifth treatment alternative in which the incineration ash is incorporated into a separate TRU waste glass. The six alternative processing system concepts provide progressively increasing levels of TRU waste consolidation and TRU waste form integrity. Vitrification of HLW and intermediate-level liquid wastes (ILLW) was assumed in all cases

  13. Waste management system alternatives for treatment of wastes from spent fuel reprocessing

    Energy Technology Data Exchange (ETDEWEB)

    McKee, R.W.; Swanson, J.L.; Daling, P.M.; Clark, L.L.; Craig, R.A.; Nesbitt, J.F.; McCarthy, D.; Franklin, A.L.; Hazelton, R.F.; Lundgren, R.A.

    1986-09-01

    This study was performed to help identify a preferred TRU waste treatment alternative for reprocessing wastes with respect to waste form performance in a geologic repository, near-term waste management system risks, and minimum waste management system costs. The results were intended for use in developing TRU waste acceptance requirements that may be needed to meet regulatory requirements for disposal of TRU wastes in a geologic repository. The waste management system components included in this analysis are waste treatment and packaging, transportation, and disposal. The major features of the TRU waste treatment alternatives examined here include: (1) packaging (as-produced) without treatment (PWOT); (2) compaction of hulls and other compactable wastes; (3) incineration of combustibles with cementation of the ash plus compaction of hulls and filters; (4) melting of hulls and failed equipment plus incineration of combustibles with vitrification of the ash along with the HLW; (5a) decontamination of hulls and failed equipment to produce LLW plus incineration and incorporation of ash and other inert wastes into HLW glass; and (5b) variation of this fifth treatment alternative in which the incineration ash is incorporated into a separate TRU waste glass. The six alternative processing system concepts provide progressively increasing levels of TRU waste consolidation and TRU waste form integrity. Vitrification of HLW and intermediate-level liquid wastes (ILLW) was assumed in all cases.

  14. Nuclear proliferation and civilian nuclear power: report of the Nonproliferation Alternative Systems Assessment Program. Volume VII. International perspectives

    International Nuclear Information System (INIS)

    The purpose of this volume is to assess the proliferation vulnerabilities of the present deployment of civilian nuclear-power systems within the current nonproliferation regime and, in light of their prospective deployment, to consider technical and institutional measures and alternatives which may contribute to an improved regime in which nuclear power could play a significant part. An assessment of these measures must include consideration of their nonproliferation effectiveness as well as their bearing upon energy security, and their operational, economic, and political implications. The nature of these considerations can provide some measure of their likely acceptability to various nations. While any final assessment of such measures and alternatives would have to examine the circumstances particular to each nation, it is hoped that the more generic assessments conducted here will be useful in suggesting guidelines for developing an improved nonproliferation regime which also helps to meet nuclear-energy needs. One chapter outlines the existing nonproliferation regime, including the Treaty for the Non-Proliferation of Nuclear Weapons (NPT), International Atomic Energy Agency (IAEA) safeguards, bilateral and multilateral requirements for agreements of cooperation and transfers of technology, and existing provisons for sanctions for violation of nonproliferation commitments. The chapter then proceeds to an assessment of various alternatives for providing assurance of fuel supply in light of this current regime. Another chapter examines a set of technical and institutional measures and alternatives for various components of once-through and closed fuel cycles. The components of the once-through fuel cycle assessed are enrichment services and spent-fuel management; the components of closed fuel cycles assessed are reprocessing and plutonium management and fast-breeder reactor (FBR) deployment

  15. Agri-environmental evaluation of traditional and alternative corn production systems in Chiapas, Mexico

    Directory of Open Access Journals (Sweden)

    Carlos Ernesto Aguilar-Jiménez

    2011-12-01

    Full Text Available This study evaluates the effects of environmental variables on traditional and alternative agroecosystems in three Ejidos (communal lands in the Chiapas rainforest in Mexico. The tests occurred within two seasonal agricultural cycles. In spring-summer, experiments were performed with the traditional slash, fell and burn (S-F-B system, no-burn systems and rotating systems with Mucuna deeringiana Bort., and in the autumn-winter agricultural cycle, three no-burn systems were compared to evaluate the effect of alternative sowing with corn (no-burn and topological modification of sowing. The results show a high floristic diversity in the study area (SS = 4 - 23%, with no significant differences among the systems evaluated. In the first cycle, the analysis of the agronomical variables of the corn indicated better properties in the fallowing systems, with an average yield of 1950 kg ha‑1, but there was variation related to the number of years left fallow. In the second cycle, the yields were positive for the alternative technology (average yield 3100 kg ha‑1. The traditional S-F-B systems had reduced pests and increased organic matter and soil phosphorous content. These results are the consequence of fallow periods and adaptation to the environment; thus, this practice in the Chiapas rainforest constitutes an ethnocultural reality, which is unlikely to change in the near future if the agrosystems are managed based on historical principles.

  16. Real time Aanderaa current meter data collection system

    Digital Repository Service at National Institute of Oceanography (India)

    AshokKumar, K.; Diwan, S.G.

    Aanderaa current meters are widely used for recording the current speed and such other 4 parameters by deploying them over extended period of time. Normally data are recorded on magnetic tape and after recovery of current meters, data are read...

  17. Life Cycle Multi-Criteria Analysis Of Alternative Energy Supply Systems For A Residential Building

    Directory of Open Access Journals (Sweden)

    Artur Rogoža

    2013-12-01

    Full Text Available The article analyses energy supply alternatives for a partially renovated residential building. In addition to the existing district heating (base case alternative systems, gas boilers, heat pumps (air-water and ground-water, solar collectors, solar cells, and combinations of these systems have been examined. Actual heat consumption of the building and electricity demand determined by the statistical method are used for simulating the systems. The process of simulation is performed using EnergyPro software. In order to select an optimal energy supply option, the life cycle analysis of all systems has been carried out throughout a life span of the building, and the estimated results of energy, environmental and economic evaluation have been converted into non-dimensional variables (3E using multi–criteria analysis.Article in Lithuanian

  18. Well-To-Wheel based fiscal systems. Can a WTW fiscal basis accelerate the introduction of alternative fuels?

    International Nuclear Information System (INIS)

    This report explores to which extent alternative, (partially) Well-To-Wheel based fiscal systems may accelerate the introduction of low-carbon fuels and vehicles. The design of two alternative fiscal systems is described, as well as the challenges that any fiscal system must meet. The alternative systems are compared to the existing fiscal system with regard to (1) the extent to which they honour the 'polluter pays' principle, (2) the extent to which they are expected to accelerate the introduction of (alternative) gaseous fuels, liquid biofuels, and zero-emission vehicles, (3) their expected impact on the vehicle stock, and (4) a number of (undesired) side-effects. The results show that the alternative systems provide a stronger fiscal support for some alternative fuels and vehicles, but not for all.

  19. High Voltage Resistive Divider Based on Cast Microwire in Glass Insulation on 6–24 kV Alternating Current of Commercial Frequency.

    Directory of Open Access Journals (Sweden)

    Juravleov A.

    2008-12-01

    Full Text Available It is presented the analysis and description of the construction of the high voltage resistive divider on the base of cast microwire in glass insulation on 6–24 kV alternating current of commercial frequency. It is presented the procedure of compensation of frequency error during the process of fabrication of divides and results of tests of the sample model of the divider as well.

  20. Endotoxin concentration in poultry houses for laying hens kept in cages or in alternative housing systems

    OpenAIRE

    Huneau-Salaün, Adeline; Le Bouquin, Sophie; Bex-Capelle, Valérie; Huonnic, Didier; Balaine, Loïc; Guillam, Marie-Thérèse; Squizani, Fabrice; Ségala, Claire; Michel, Virginie

    2011-01-01

    Abstract 1. Endotoxins as components of organic dust may have adverse effects on the respiratory health of workers in poultry buildings. The move towards more welfare-friendly housing systems for layers may increase worker exposure to air contaminants due to the use of litter. 2. The endotoxin concentrations in the inhalable fraction of airborne dust (below 100 ?m) from cage and alternative system henhouses (on-floor, free range and aviaries) were compared under both experiment...

  1. Optimality Properties of Alternative Systems of Taxation of Foreign Capital Income

    OpenAIRE

    1994-01-01

    Foreign source capital income taxes are examined from the point of view of of optimal taxation. In the framework of a simple economy with international real capital flows, a taxonomy of alternative systems of such taxation is first presented, showing how crediting and other tax parameters induce what are called source-based, residence-based and related systems. Next, tax rates are determined that are optimal from a single country's point of view, given those of the others. The achievability o...

  2. Optimality properties of alternative systems of taxation of foreign capital income. J. Public Econ.

    OpenAIRE

    Mintz, J

    1996-01-01

    Foreign source capital income taxes are examined from the point of view of optimal taxation. In the framework of a simple economy with international real capital flows, a taxonomy of alternative systems of such taxation is first presented, showing how crediting and other tax parameters induce what are called source-based, residence-based and related systems. Next, tax rates are determined that are optimal from a single country's point of view, given those of the others. The achievability of t...

  3. ALTERNATIVE WHEAT COLLECTION AND TRANSPORTATION SYSTEMS FOR THE SOUTHERN U.S. PLAINS

    OpenAIRE

    Fuller, Stephen W.; Sorenson, L. Orlo; Johnson, Marc A.; Oehrtman, Robert L.

    1981-01-01

    This study examines means of improving efficiency of the transportation portion of the export wheat handling system in the southern Plains. Analysis focuses on the feasibility of restructuring grain handling facilities to accommodate unit train movements to port locations. To accomplish this, a cost-minimizing network flow model was developed. Results show that the alternative transportation systems would have substantial effects on costs, wheat flow patterns and the economic variability of c...

  4. Evidence of Encapsulated Learning Systems in an Alternating Serial Reaction Time Task

    OpenAIRE

    McConville, Dan

    2011-01-01

    A model of learning systems that has received wide acknowledgment is that promulgated by Squire (1992). The model describes explicit and implicit learning systems as being encapsulated and operating in parallel. This paper aimed to investigate if implicit procedural sequence learning could be affected by explicit learning processes in an alternating serial reaction time task (ASRTT). The ASRTT involved visual-stimuli appearing in one of four spatial-locations placed horizo...

  5. Discrete changes of current statistics in periodically driven stochastic systems

    International Nuclear Information System (INIS)

    We demonstrate that the counting statistics of currents in periodically driven ergodic stochastic systems can show sharp changes of some of its properties in response to continuous changes of the driving protocol. To describe this effect, we introduce a new topological phase factor in the evolution of the moment generating function which is akin to the topological geometric phase in the evolution of a periodically driven quantum mechanical system with time-reversal symmetry. This phase leads to the prediction of a sign change for the difference of the probabilities to find even and odd numbers of particles transferred in a stochastic system in response to cyclic evolution of control parameters. The driving protocols that lead to this sign change should enclose specific degeneracy points in the space of control parameters. The relation between the topology of the paths in the control parameter space and the sign changes can be described in terms of the first Stiefel–Whitney class of topological invariants. (letter)

  6. Central neural control of the cardiovascular system: current perspectives.

    Science.gov (United States)

    Dampney, Roger A L

    2016-09-01

    This brief review, which is based on a lecture presented at the American Physiological Society Teaching Refresher Course on the Brain and Systems Control as part of the Experimental Biology meeting in 2015, aims to summarize current concepts of the principal mechanisms in the brain that regulate the autonomic outflow to the cardiovascular system. Such cardiovascular regulatory mechanisms do not operate in isolation but are closely coordinated with respiratory and other regulatory mechanisms to maintain homeostasis. The brain regulates the cardiovascular system by two general means: 1) feedforward regulation, often referred to as "central command," and 2) feedback or reflex regulation. In most situations (e.g., during exercise, defensive behavior, sleep, etc.), both of these general mechanisms contribute to overall cardiovascular homeostasis. The review first describes the mechanisms and central circuitry subserving the baroreceptor, chemoreceptor, and other reflexes that work together to regulate an appropriate level of blood pressure and blood oxygenation and then considers the brain mechanisms that defend the body against more complex environmental challenges, using dehydration and cold and heat stress as examples. The last section of the review considers the central mechanisms regulating cardiovascular function associated with different behaviors, with a specific focus on defensive behavior and exercise. PMID:27445275

  7. OPEN AND DISTANCE LEARNING: An Emerging System for Alternative Higher Education in Nigeria

    Directory of Open Access Journals (Sweden)

    Emmanuel Chisa IBARA

    2008-01-01

    Full Text Available ABSTRACT Nigeria no doubt is at the threshold of transformation in information and communication technology (ICT, a development that should be utilized to meet the demand of time, especially in the education sector. One area in which ICT has made enormous impact is in open and distance learning. Undoubtedly, the demand on the conventional higher education delivery system in the country is high and ever increasing that the system at the moment is unable to accommodate the number of candidates seeking admission. This paper, therefore, attempts some definition of open and distance learning as well as its practices with a view to advancing the prospects of open and distance as alternative system of higher education in Nigeria. Furthermore, it concludes that considering the level of infrastructural decay in the conventional higher education system, open and distance learning as an alternative system of education has become imperative for the realization of the primary objectives of higher education in Nigeria. Recommendations that will enhance the prospects of open and distance learning as viable alternative system of higher education were proffered.

  8. Alternatives generation and analysis for the Phase I intermediate waste feed staging system design requirements

    Energy Technology Data Exchange (ETDEWEB)

    Claghorn, R.D., Fluor Daniel Hanford

    1997-02-06

    This alternatives generation and analysis (AGA) addresses the question: What is the design basis for the facilities required to stage low-level waste (LLW) feed to the Phase I private contractors? Alternative designs for the intermediate waste feed staging system were developed, analyzed, and compared. Based on these analyses, this document recommends installing mixer pumps in the central pump pit of double-shell tanks 241-AP-102 and 241-AP-104. Also recommended is installing decant/transfer pumps at these tanks. These recommendations have clear advantages in that they provide a low shedule impact/risk and the highest operability of all the alternatives investigated. This revision incorporates comments from the decision board.

  9. Impacts of Western Area Power Administration's power marketing alternatives on electric utility systems

    International Nuclear Information System (INIS)

    This technical memorandum estimates the effects of alternative contractual commitments that may be initiated by the Western Area Power Administration's Salt Lake City Area Office. It also studies hydropower operational restrictions at the Salt Lake City Area Integrated Projects in combination with these alternatives. Power marketing and hydropower operational effects are estimated in support of Western's Electric Power Marketing Environmental Impact Statement (EIS). Electricity production and capacity expansion for utility systems that will be directly affected by alternatives specified in the EIS are simulated. Cost estimates are presented by utility type and for various activities such as capacity expansion, generation, long-term firm purchases and sales, fixed operation and maintenance expenses, and spot market activities. Operational changes at hydropower facilities are also investigated

  10. Numerical and theoretical evaluations of AC losses for single and infinite numbers of superconductor strips with direct and alternating transport currents in external AC magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Kajikawa, K., E-mail: kajikawa@sc.kyushu-u.ac.j [Research Institute of Superconductor Science and Systems, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395 (Japan); Funaki, K. [Research Institute of Superconductor Science and Systems, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395 (Japan); Shikimachi, K.; Hirano, N.; Nagaya, S. [Chubu Electric Power Co., Inc., 20-1 Kitasekiyama, Ohdaka-cho, Midori-ku, Nagoya 459-8522 (Japan)

    2010-11-01

    AC losses in a superconductor strip are numerically evaluated by means of a finite element method formulated with a current vector potential. The expressions of AC losses in an infinite slab that corresponds to a simple model of infinitely stacked strips are also derived theoretically. It is assumed that the voltage-current characteristics of the superconductors are represented by Bean's critical state model. The typical operation pattern of a Superconducting Magnetic Energy Storage (SMES) coil with direct and alternating transport currents in an external AC magnetic field is taken into account as the electromagnetic environment for both the single strip and the infinite slab. By using the obtained results of AC losses, the influences of the transport currents on the total losses are discussed quantitatively.

  11. Numerical and theoretical evaluations of AC losses for single and infinite numbers of superconductor strips with direct and alternating transport currents in external AC magnetic field

    Science.gov (United States)

    Kajikawa, K.; Funaki, K.; Shikimachi, K.; Hirano, N.; Nagaya, S.

    2010-11-01

    AC losses in a superconductor strip are numerically evaluated by means of a finite element method formulated with a current vector potential. The expressions of AC losses in an infinite slab that corresponds to a simple model of infinitely stacked strips are also derived theoretically. It is assumed that the voltage-current characteristics of the superconductors are represented by Bean’s critical state model. The typical operation pattern of a Superconducting Magnetic Energy Storage (SMES) coil with direct and alternating transport currents in an external AC magnetic field is taken into account as the electromagnetic environment for both the single strip and the infinite slab. By using the obtained results of AC losses, the influences of the transport currents on the total losses are discussed quantitatively.

  12. Fast Decoupled Power Flow for Power System with High Voltage Direct Current Transmission Line System

    OpenAIRE

    Prechanon Kumkratug

    2010-01-01

    Problem statement: High voltage direct current transmission line system has been widely applied for control power flow in power system. The power flow analysis was the one of powerful tools by which the power system equipped was analyzed both for planning and operation strategies. Approach: This study presented the method to analyze power flow of power system consisted of HVDC system. HVDC was modeled as the complex power injections. The presented complex power injected was incorporated into ...

  13. Global modeling of Hanford tank waste pretreatment alternatives within a total cleanup system using ASPEN PLUS trademark

    International Nuclear Information System (INIS)

    The purpose of this work is to evaluate and compare radionuclide separations/processing technologies being developed or considered as Hanford tank waste pretreatment alternatives. These technologies are integrated into a total cleanup system that includes tank waste retrieval, treatment, and disposal. Current Hanford flowsheets typically include only mature, developed technologies, not new technologies. Thus, this work examines the impact/benefits of inserting new technologies into Hanford flowsheets. Waste treatment must produce disposal fractions which are less troublesome than the original material. Researchers seeking effective treatment methods may lack the tools or expertise to fully understand the implications of their approach in terms of secondary and tertiary waste streams or the extent to which a unique new process will affect upstream or downstream processes. This work has developed and demonstrated mass balance methods that clarify the effect of including individual processes in an integrated waste treatment system, such as the Hanford cleanup system. The methods provide a measure of treatment effectiveness and a format for the researcher to understand waste stream interrelationships and determine how a particular treatment technology can best be used in a cleanup system. A description of the Hanford tank waste cleanup model developed using the ASPEN PLUS flowsheet simulation tool is given. Important aspects of the modeling approach are discussed along with a description of how performance measures were developed and integrated within the simulation to evaluate and compare various Hanford tank waste pretreatment alternatives

  14. Current views on etiopathogenesis of systemic lupus erythematosus

    Directory of Open Access Journals (Sweden)

    Agnieszka Klonowska-Szymczyk

    2011-11-01

    Full Text Available The article is a review of information concerning etiopathogenesis of systemic lupus erythematosus (SLE. Due to the risk of serious complications, including death, the clarification of etiology could result in substantial improvement or even complete cure of the disease. Progress in scientific research of observed disorder mechanisms together with implementation of appropriate therapies contributed to a higher detection rate, improved course and decreased mortality in SLE. However, there are still many doubts, which legitimate the need of further research. A significant role in development of the disease and further exacerbations is played by environmental factors. Therefore, decreased exposure to UV light, female sex hormone and microbial antigens is associated with improved course and decreased frequency of exacerbations. Less is known about the genetic basis of SLE, which results from a multigene disease background and complex hereditary mechanisms. It is estimated that the disease may be conditioned by around 100 genes, that only in part are functionally determined. Only part of them is already functionally characterized. The role played by most of them is still unknown. Research currently being conducted is aimed at detecting genetic polymorphism in large and genetically diverse populations. It will allow evaluation of the role of a particular gene in protein biosynthesis, which is responsible for development of regulatory process disturbances, commonly observed in the course of SLE. The article presents current directions of research and the latest advances in epidemiology as well as environmental and genetic risk factors of SLE.

  15. Equilibrium balking strategies for a clearing queueing system in alternating environment

    CERN Document Server

    Economou, Antonis

    2011-01-01

    We consider a Markovian clearing queueing system, where the customers are accumulated according to a Poisson arrival process and the server removes all present customers at the completion epochs of exponential service cycles. This system may represent the visits of a transportation facility with unlimited capacity at a certain station. The system evolves in an alternating environment that influences the arrival and the service rates. We assume that the arriving customers decide whether to join the system or balk, based on a natural linear reward-cost structure. We study the balking behavior of the customers and derive the corresponding Nash equilibrium strategies under various levels of information.

  16. [Current cell therapy strategies for repairing the central nervous system].

    Science.gov (United States)

    Féron, F

    2007-09-01

    One of the chief contemporary goals of neurologists and neuroscientists is to find a way to overcome the debilitating effects of brain diseases, especially neurodegenerative diseases. Since very few molecules have been found to be efficient in curing the patients and even halting the progression of the symptoms, cell therapy is now seen as an attractive alternative. Two therapeutic strategies are currently under investigation: i) the "substitution" strategy, based on grafts of cells capable of differentiating in the appropriate cells and restoring lost functions and ii) the "neuroprotective" or "conservative" strategy aiming to increase the resistance of spared cells to the toxicity of their environment and to reinforce the body's own mechanisms of healing. Twenty years ago, foetal neuroblasts were the first cells to be transplanted in the brains of patients with Parkinson's or Huntington disease. A phase II clinical trial is presently conducted in France for the latter disorder. However, the numerous ethical and technical issues raised by the use of embryonic and foetal cells have directed the focus of clinicians and researchers towards substitute cell types. In this review, we summarise the main findings of the most recent basic studies and clinical trials based on: i) the grafting of surrogate adult cells such as bone marrow mesenchymal stem cells and olfactory ensheathing cells; ii) the potential therapeutic applications of neuropoiesis - the persistent neurogenesis in the brain - as a source for tissue engraftment and as self-repair by a person's own indigenous population of pluripotent cells and iii) immune-based therapy (autologous activated macrophages and T cell vaccination) as well as administration of immunomodulatory molecules. Unexpectedly, it has been found that undifferentiated adult stem cells can display immune-like functions when they home in on an inflamed brain area while immune cells and immunosuppressors can improve functional and

  17. Yaw Systems for wind turbines – Overview of concepts, current challenges and design methods

    International Nuclear Information System (INIS)

    Looking at the upscaling of the rotor diameter not only the loss in power production but the aerodynamic loads arising from yaw misalignment will have an increasing impact on the yaw system design in future wind turbines. This paper presents an overview of yaw systems used in current wind turbines and a review of patents with regards to the yaw system. The current state of the art of yaw systems has been analyzed through a systematic literature review. Further a patent analysis has been done through the European Patent Office. Todays design and strength requirements as per IEC and GL standards will be reviewed and alternative design calculations will be discussed. Over 100 patents have been identified as relevant to the yaw system and have been analyzed. It has been found that most patents are dealing with load reduction possibilities on the yaw system, where fatigue loads seem more of a problem than ultimate loads. Most of these patents concern especially the yaw actuator, which consists of multiple electrical motors, reduction gears and shaft pinions. This is due to the nature of the gearing in the actuator and the gearing between the shaft pinion and the ring gear. This coincides with the patents for yaw brakes, which mostly aim to reduce the fatigue loads during yaw maneuverer and during nacelle standstill. Patents for the yaw bearing are incorporating the reduction of loads through the usage of friction bearings or different bearing arrangement approaches. The paper shows that the conventional yaw system designs are still trying to meet the high requirements regarding the lifetime of a wind turbine and turbulent wind loads. New designs for yaw systems in general are hard to find. Many patents concentrate on control algorithms that depend on additional instruments and incorporate electromechanical systems

  18. Evaluation of advanced and current leak detection systems

    International Nuclear Information System (INIS)

    U.S. Nuclear Regulatory Commission Guide 1.45 recommends the use of at least three different detection methods in reactors to detect leakage. Monitoring of both sump-flow and airborne particulate radioactivity is mandatory. A third method can involve either monitoring of condensate flow rate from air coolers or monitoring of airborne gaseous radioactivity. Although the methods currently used for leak detection reflect the state of the art, other techniques may be developed and used. Since the recommendations of Regulatory Guide 1.45 are not mandatory, Licensee Event Report Compilations have been reviewed to help establish actual capabilities for leak detection. The review of event reports, which had previously covered the period of June 1985 to August 1986 has been extended, and now covers events to June 1987. The total number of significant events is now 83. These reports have provided documented, sometimes detailed, summaries of reactor leaks. They have helped establish the capabilities of existing systems to detect and locate leaks. Differences between PWRs and BWRs with regard to leak detection have now been analyzed. With regard to detection methods, the greatest differences between reactor types are as follows: (a) The sump pump is reported as the detection method more frequently in BWRs than in PWRs (64% vs. 35%). (b) The radiation monitor is reported as the detection method (excluding false alarms) more frequently in PWRs. Current efforts at Argonne National Laboratory (ANL) to evaluate advanced acoustic leak detection methods are directed toward the generation and analysis of acoustic data from large (0.5 to 10 gal/min) leaks and modification of the software of the GARD/ANL advanced acoustic leak detection system. In order to reach the goal of 10 gal/min leaks, the Steam Generator Test Facility at ANL has been modified to carry out the leak testing. Tests were carried out with water at 525 deg. F and 1100 psi leaking through a fatigue crack in a 4-in

  19. Study on an alternating current electrothermal micropump for microneedle-based fluid delivery systems

    Science.gov (United States)

    Zhang, Rumi; Jullien, Graham A.; Dalton, Colin

    2013-07-01

    In this paper, we report on a modeling study of an AC electrothermal (ACET) micropump with high operating pressures as well as fast flow rates. One specific application area is for fluid delivery using microneedle arrays which require higher pressures and faster flow rates than have been previously reported with ACET devices. ACET is very suitable for accurate actuation and control of fluid flow, since the technique has been shown to be very effective in high conductivity fluids and has the ability to create a pulsation free flow. However, AC electrokinetic pumps usually can only generate low operating pressures of 1 to 100 Pa, where flow reversal is likely to occur with an external load. In order to realize a high performance ACET micropump for continuous fluid delivery, applying relatively high AC operating voltages (20 to 36 Vrms) to silicon substrate ACET actuators and using long serpentine channel allows the boosting of operating pressure as well as increasing the flow rates. Fast pumping flow rates (102-103 nl/s) and high operating pressures (1-12 kPa) can be achieved by applying both methods, making them of significant importance for continuous fluid delivery applications using microneedle arrays and other such biomedical devices.

  20. Environmental effects of cooling system alternatives at inland and coastal sites

    International Nuclear Information System (INIS)

    The environmental effects of alternative cooling systems for power plants in California were analyzed. At inland sites evaporative cooling systems must be used, with fresh water or waste water used as makeup. Because fresh water is scarce, most new plants would need to use agricultural or municipal waste waters. For agricultural waste water systems, disposing of the blowdown and dispersion of drift containing total dissolved solids are two significant problems requiring resolution. At coastal sites, once-through cooling systems or recirculating systems could be used. Once--through cooling causes fewer effects on the marine environment than do recirculating systems on the air and marine environment when oceans water makeup is used. In general, for a recirculating system, dispersing high-salinity blowdown in marine waters and the effects of salt water drift on the terrestrial ecology outweigh the effects of once-through warm water on marine life. (U.S.)

  1. A Study of Second-Year Engineering Students' Alternative Conceptions about Electric Potential, Current Intensity and Ohm's Law

    Science.gov (United States)

    Periago, M. Cristina; Bohigas, Xavier

    2005-01-01

    The aim of this research was to evaluate and analyse second-year industrial engineering and chemical engineering students prior knowledge of conceptual aspects of "circuit theory". Specifically, we focused on the basic concepts of electric potential and current intensity and on the fundamental relationship between them as expressed by Ohm's law.…

  2. The Optimal Interest Rates and the Current Interest Rate System

    Directory of Open Access Journals (Sweden)

    Ioannis N. Kallianiotis

    2014-12-01

    Full Text Available The paper discusses the current target interest rate, which is closed to zero with the new experiment of quantitative easing since 2009 and has reduced the rate of return and the income and has made the real savings rate negative. This target rate has not reduced unemployment and has not improved growth (it is not optimal, but has increased the debt of individuals and the low taxes on businesses have magnified the budget deficits and the national debt. People were borrowing the present value of their uncertain future wealth and their high debt and low income raise the risk and this high risk premium heighten the interest rate on loans, especially on credit cards. The current monetary system needs to be changed and an interest rate floor on deposits (savings and an interest rate ceiling on individuals‟ loans (borrowings is necessary to improve social welfare, fairness, and justice in our society and not to support only disintermediation (financial markets. The middle class cannot work only to pay taxes and interest on its debt (redistribution of their wealth to government and banks or worse to be in chronic unemployment. Many home owners defaulted on their loans payments and their homes are foreclosed. They will end up without property (real assets. The unconcern towards the middle class will affect negatively the entire socio-economic structure of the nation and after losing its productive power, it will start declining, as history has shown to us with so many empires that do not exist anymore. We hope the leaders (the democratic governments to improve public policies, to regulate the financial market and institutions, and to satisfy their policy ultimate objective, which is citizens‟ perfection and the nation‟s highest point of prosperity.

  3. The two-dimensional alternative binary L-J system: liquid-gas phase diagram

    Institute of Scientific and Technical Information of China (English)

    张陟; 陈立溁

    2003-01-01

    A two-dimensional (2D) binary system without considering the Lennard-Jones (L-J) potential has been studied by using the Collins model. In this paper, we introduce the L-J potential into the 2D binary system and consider the existence of the holes that are called the "molecular fraction". The liquid-gas phase diagram of the 2D alternative binary L-J system is obtained. The results are quite analogous to the behaviour of 3D substances.

  4. Chitosan and Sodium Alginate Combinations Are Alternative, Efficient, and Safe Natural Adjuvant Systems for Hepatitis B Vaccine in Mouse Model

    Science.gov (United States)

    AbdelAllah, Nourhan H.; Boseila, Abeer A.; Amin, Magdy A.

    2016-01-01

    Hepatitis B viral (HBV) infections represent major public health problem and are an occupational hazard for healthcare workers. Current alum-adjuvanted HBV vaccine is the most effective measure to prevent HBV infection. However, the vaccine has some limitations including poor response in some vaccinee and being a frost-sensitive suspension. The goal of our study was to use an alternative natural adjuvant system strongly immunogenic allowing for a reduction in dose and cost. We tested HBV surface antigen (HBsAg) adjuvanted with chitosan (Ch) and sodium alginate (S), both natural adjuvants, either alone or combined with alum in mouse model. Mice groups were immunized subcutaneously with HBsAg adjuvanted with Ch or S, or triple adjuvant formula with alum (Al), Ch, and S, or double formulations with AlCh or AlS. These were compared to control groups immunized with current vaccine formula or unadjuvanted HBsAg. We evaluated the rate of seroconversion, serum HBsAg antibody, IL-4, and IFN-γ levels. The results showed that the solution formula with Ch or S exhibited comparable immunogenic responses to Al-adjuvanted suspension. The AlChS gave significantly higher immunogenic response compared to controls. Collectively, our results indicated that Ch and S are effective HBV adjuvants offering natural alternatives, potentially reducing dose. PMID:27493674

  5. A Floquet description of phase alternated sequences for efficient homonuclear recoupling in solid perdeuterated systems

    Science.gov (United States)

    Jayanthi, Sundaresan; Akbey, Ümit; Uluca, Boran; Oschkinat, Hartmut; Vega, Shimon

    2013-09-01

    A Floquet description of a phase alternated homonuclear recoupling scheme for perdeuterated systems is presented. As a result, we demonstrate improvements in the recoupling efficiency of the DOuble Nucleus Enhanced Recoupling [DONER; J. Am. Chem. Soc. 131 (2009) 17054] technique by utilizing Phase Alternated Recoupling Irradiation Schemes [PARIS; Chem. Phys. Lett. 469 (2009) 342]. The effect of proton and deuterium radio frequency irradiation during recoupling has been systematically studied and theoretical observations have been verified experimentally using a deuterated model compound, L-Alanine, at 10 and 20 kHz magic angle spinning frequency. Experimental results are well in agreement with theoretical observations, thereby significantly increasing the recoupling efficiency of conventional DONER in perdeuterated systems.

  6. From a Literature Review to an Alternative Treatment System for Landfill Gas and Leachate

    Directory of Open Access Journals (Sweden)

    Tao Huang

    2012-12-01

    Full Text Available This paper provides an alternative treatment system for landfill gas and leachate control in order to reduce the energy consumption and disposal cost, using the recycled landfill gas as the combustion promoter for incineration of the leachate. This study starts by providing a literature review to summarize and analyze different approaches being applied to landfill leachate treatment. Subsequently, a conceptual prototype is proposed, which can be built using existing technology by means of technical possibility analysis, whilst economic benefits could be returned through preliminary comparison. With the proposed introduction of a “waste treatment park”, this alternative treatment system could provide a template for leachate and landfill gas control. This study may provide an insight for landfill operators and engineers to promote the transformation from the conceptual framework to the real achievement. Finally, the limitations of the conceptual model and analysis are discussed, laying a foundation for further work.

  7. Alternating current losses of a 10 metre long low loss superconducting cable conductor determined from phase sensitive measurements

    DEFF Research Database (Denmark)

    Olsen, Søren Krüger; Kühle (fratrådt), Anders Van Der Aa; Træholt, Chresten;

    1999-01-01

    The ac loss of a superconducting cable conductor carrying an ac current is small. Therefore the ratio between the inductive (out-of-phase) and the resistive (in-phase) voltages over the conductor is correspondingly high. In vectorial representations this results in phase angles between the current...... and the voltage over the cable close to 90 degrees. This has the effect that the loss cannot be derived directly using most commercial lock-in amplifiers due to their limited absolute accuracy. However, by using two lock-in amplifiers and an appropriate correction scheme the high relative accuracy of...... such lock-in amplifiers can be exploited. In this paper we present the results from ac-loss measurements on a low loss 10 metre long high temperature superconducting cable conductor using such a correction scheme. Measurements were carried out with and without a compensation circuit that could reduce...

  8. Development of Alternative Crab Claw Processing Systems to Minimize Environmental Impact

    OpenAIRE

    Benning, Jennifer Lyn

    1997-01-01

    Development of Alternative Crab Claw Processing Systems to Minimize Environmental Impact by Jennifer Lyn Benning Chair: Dr. Gregory Boardman Environemental Engineering (ABSTRACT) In the recent years, environmental regulations enforced by federal,state, and local agencies have increasingly addressed water quality issues through progressively more stringent regulations. These regulations have raised concerns in the blue crab industry because processors are now subject to regulations u...

  9. Alternatives generation and analysis for double-shell tank primary ventilation systems emissions control and monitoring

    Energy Technology Data Exchange (ETDEWEB)

    SEDERBURG, J.P.

    1999-09-30

    This AGA addresses the question: ''What equipment upgrades, operational changes, and/or other actions are required relative to the DST tanks farms' ventilation systems to support retrieval, staging (including feed sampling), and delivery of tank waste to the Phase I private contractor?'' Issues and options for the various components within the ventilation subsystem affect each other. Recommended design requirements are presented and the preferred alternatives are detailed.

  10. Alternatives generation and analysis for double-shell tank primary ventilation systems emissions control and monitoring

    International Nuclear Information System (INIS)

    This AGA addresses the question: ''What equipment upgrades, operational changes, and/or other actions are required relative to the DST tanks farms' ventilation systems to support retrieval, staging (including feed sampling), and delivery of tank waste to the Phase I private contractor?'' Issues and options for the various components within the ventilation subsystem affect each other. Recommended design requirements are presented and the preferred alternatives are detailed

  11. DataDotDNA: an alternative marking system for tortoises of genus Testudo

    Directory of Open Access Journals (Sweden)

    Luca Brugnola

    2013-12-01

    Full Text Available It was analyzed the effectiveness of one method of individual and unique marking, alternative to the application of microchip, on 17 specimens of Testudo hermanni through DataDotDNA technology. This technology has proven to be an effective system of marking of Testudo spp., answering the need for unambiguous identification of individuals. Further advantages are the easy application and reading, the long-term resistance as well as the difficulties of possible fraudulent tampering.

  12. From a Literature Review to an Alternative Treatment System for Landfill Gas and Leachate

    OpenAIRE

    Tao Huang; Michael McGuire; Rui Zhao

    2012-01-01

    This paper provides an alternative treatment system for landfill gas and leachate control in order to reduce the energy consumption and disposal cost, using the recycled landfill gas as the combustion promoter for incineration of the leachate. This study starts by providing a literature review to summarize and analyze different approaches being applied to landfill leachate treatment. Subsequently, a conceptual prototype is proposed, which can be built using existing technology by means of tec...

  13. Nuclear power systems: Their safety. Current issue review

    International Nuclear Information System (INIS)

    Human beings utilize energy in many forms and from a variety of sources. A number of countries have chosen nuclear-electric generation as a component of their energy system. At the end of 1992, there were 419 power reactors operating in 29 countries, accounting for more than 15% of the world's production of electricity. In 1992, 13 countries derived at least 25% of their electricity from nuclear units, with Lithuania leading at just over 78%, followed closely by France at 72%. In the same year, Canada produced about 16% of its electricity from nuclear units. Some 53 power reactors are under construction in 14 countries outside the former USSR. Within the ex-USSR countries, six new reactors are currently under construction. No human endeavour carries the guarantee of perfect safety and the question of whether of not nuclear-electric generation represents an 'acceptable' risk to society has long been vigorously debated. Until the events of late April 1986 in the then Soviet Union, nuclear safety had indeed been an issue for discussion, for some concern, but not for alarm. The accident at the Chernobyl reactor irrevocably changed all that. This disaster brought the matter of nuclear safety into the public mind in a dramatic fashion. Subsequent opening of the ex-Soviet nuclear power program to outside scrutiny has done little to calm people's concerns about the safety of nuclear power in that part of the world. This paper discusses the issue of safety in complex energy systems and provides brief accounts of some of the most serious reactor accidents that have occurred to date, as well as more recent, less dramatic events touching on the safety issue. (author). 7 refs

  14. Evaluation of advanced and current leak detection systems

    International Nuclear Information System (INIS)

    Differences between PWRs and BWRs with regard to leak detection have now been analyzed. With regard to detection methods, the greatest differences between reactor types are as follows: (a) the sump pump is reported as the detection method more frequently in BWRs than in PWRs (64% vs. 35%); (b) the radiation monitor is reported as the detection method (excluding false alarms) more frequently in PWRs. Current efforts at Argonne National Laboratory (ANL) to evaluate advanced acoustic leak detection methods are directed toward the generation and analysis of acoustic data from large (0.5 to 10 gal/min) leaks and modification of the software of the GARD/ANL advanced acoustic leak detection system. In order to reach the goal of 10 gal/min leaks, the Steam Generator Test Facility at ANL has been modified to carry out the leak testing. Tests were carried out with water at 5250F and 1100 psi leaking through a fatigue crack in a 4-in. schedule 80 pipe. The crack opening can be varied and was set to generate 0.6- to 8.5-gal/min leaks. Acoustic signals were analyzed with respect to rms values, frequency content, and cross-correlation functions. The GARD/ANL advanced acoustic leak detection system software has been modified to permit intelligent continuous acoustic leak monitoring of reactor components. In the monitor mode the computer continually evaluates the rms signal output of acoustic leak detection sensors placed on the primary circuit. If a leak is suspected, acoustic signals are captured and analyzed to determine the source of the leak, the location and estimated leak rate

  15. Monitoring tidal currents with a towed ADCP system

    Science.gov (United States)

    Sentchev, Alexei; Yaremchuk, Max

    2016-01-01

    The tidal circulation in the semi-enclosed Boulogne harbour (eastern English Channel) is measured during the various stages of the tidal cycle with a low-cost towed Acoustic Doppler Current Profiler (ADCP) system for the first time. The system is equipped with an interpolation algorithm which allows reconstructing space-time evolution of the velocity field for surveys whose duration is comparable or larger than the typical time of tidal variation (1-2 h). The method employs space-time velocity covariances derived from a numerical simulation of the surveyed area by a high-resolution relocatable model "Model for Applications on Regional Scale" (MARS). The covariances are utilized by the optimal interpolation algorithm to obtain the most likely evolution of the velocity field under the constraints provided by the ADCP observations and their error statistics. Technically, the MARS model run provides the first guess (background) evolution of the velocity field in the surveyed area which is then corrected by the data in a statistically consistent manner as it explicitly takes into the account both observational and modeling errors. The quality of the velocity reconstruction was validated against independent bottom-mounted ADCP data, the background model evolution, and against the results of spatial interpolation by Kriging technique. All tests demonstrated significant (30 to 60 %) reduction of the model-data misfit for the velocity field obtained as a result of space-time optimal interpolation. Although the method was applied to recover surface circulation, it can be extended for assessment of the full 4D tidal flow dynamics using the data recorded throughout the entire water column.

  16. Symbolic Models for Nonlinear Time-Varying Time-Delay Systems via Alternating Approximate Bisimulation

    CERN Document Server

    Pola, Giordano; Di Benedetto, Maria Domenica

    2010-01-01

    Time-delay systems are an important class of dynamical systems that provide a solid mathematical framework to deal with many application domains of interest. In this paper we focus on nonlinear control systems with unknown and time-varying delay signals and we propose one approach to the control design of such systems, which is based on the construction of symbolic models. Symbolic models are abstract descriptions of dynamical systems in which one symbolic state and one symbolic input correspond to an aggregate of states and an aggregate of inputs. We first introduce the notion of incremental input-delay-to-state stability and characterize it by means of Liapunov-Krasovskii functionals. We then derive sufficient conditions for the existence of symbolic models that are shown to be alternating approximately bisimilar to the original system. Further results are also derived which prove the computability of the proposed symbolic models in a finite number of steps.

  17. Energy and cost saving results for advanced technology systems from the Cogeneration Technology Alternatives Study (CTAS)

    Science.gov (United States)

    Sagerman, G. D.; Barna, G. J.; Burns, R. K.

    1979-01-01

    An overview of the organization and methodology of the Cogeneration Technology Alternatives Study is presented. The objectives of the study were to identify the most attractive advanced energy conversion systems for industrial cogeneration applications in the future and to assess the advantages of advanced technology systems compared to those systems commercially available today. Advanced systems studied include steam turbines, open and closed cycle gas turbines, combined cycles, diesel engines, Stirling engines, phosphoric acid and molten carbonate fuel cells and thermionics. Steam turbines, open cycle gas turbines, combined cycles, and diesel engines were also analyzed in versions typical of today's commercially available technology to provide a base against which to measure the advanced systems. Cogeneration applications in the major energy consuming manufacturing industries were considered. Results of the study in terms of plant level energy savings, annual energy cost savings and economic attractiveness are presented for the various energy conversion systems considered.

  18. Integrated Application of Active Controls (IAAC) technology to an advanced subsonic transport project: Current and advanced act control system definition study. Volume 2: Appendices

    Science.gov (United States)

    Hanks, G. W.; Shomber, H. A.; Dethman, H. A.; Gratzer, L. B.; Maeshiro, A.; Gangsaas, D.; Blight, J. D.; Buchan, S. M.; Crumb, C. B.; Dorwart, R. J.

    1981-01-01

    The current status of the Active Controls Technology (ACT) for the advanced subsonic transport project is investigated through analysis of the systems technical data. Control systems technologies under examination include computerized reliability analysis, pitch axis fly by wire actuator, flaperon actuation system design trade study, control law synthesis and analysis, flutter mode control and gust load alleviation analysis, and implementation of alternative ACT systems. Extensive analysis of the computer techniques involved in each system is included.

  19. The Performance Evaluation of Vapor Compression Heat Pump System Using HFC Alternative Refrigerant Mixtures

    Science.gov (United States)

    Taira, Shigeharu; Yazima, Ryuzaburo; Tarutani, Isamu; Koyama, Shigeru

    This paper deals with an experimental study on the performance evaluation of heat pump systems using HFC alternative refrigerants. The tested heat pump systems are modified from the R22 use to alternative refrigerants. Refrigerant mixtures of R410A, R407C. R32/125 and R32/134a are tested. where R410A and R407C launched into global market recently. Pure refrigerants of R22, R32, R125 and R134a are also tested. The experimental results of alternative refrigerants are evaluated in comparison with the result of R22, and the following are confirmed : (1) the performance of R32 is the highest. (2) adding R125 to R32 and R32/134a results into the deterioration of the performance, (3) the use of counter flow-like heat exchangers for a zeotropic refrigerant mixtures are effective, and (4) in case of R410A. the modification of the compressor to fit operating pressure heightens the performance. The effects of the performance of components on the COP are also analyzed based on the measured thermodynamic states at both ends of components in the system. Then, it is clarified that the most effective factor is irreversibility of compressors and the following is the pressure drop in low pressure side including the evaporator and the suction pipe.

  20. General Technical Approvals for Decentralised Sustainable Urban Drainage Systems (SUDS—The Current Situation in Germany

    Directory of Open Access Journals (Sweden)

    Carsten Dierkes

    2015-03-01

    Full Text Available The use of decentralised, sustainable urban drainage systems (SUDS for the treatment of stormwater runoff is becoming increasingly prevalent in Germany. Decentralised SUDS can offer a viable and attractive alternative to end of pipe treatment systems for stormwater runoff from urban areas. However, there is still some uncertainty regarding the long-term performance of SUDS, and the general legislative requirements for SUDS approval and testing. Whilst the allowable pollution levels in stormwater runoff that infiltrate into ground and/or water table are regulated across Germany by the Federal Soil Protection Law, there is presently no federal law addressing the discharge requirements for surface water runoff. The lack of clear guidance can make it difficult for planners and designers to implement these innovative and sustainable stormwater treatment systems. This study clarifies the current understanding of urban stormwater treatment requirements and new technical approval guidelines for decentralised SUDS devices in Germany. The study findings should assist researchers, designers and asset managers to better anticipate and understand the performance, effective life-spans, and the planning and maintenance requirements for decentralised SUDS systems. This should help promote even greater use of these systems in the future.

  1. Simulating greenhouse gas budgets of four California cropping systems under conventional and alternative management.

    Science.gov (United States)

    De Gryze, Steven; Wolf, Adam; Kaffka, Stephen R; Mitchell, Jeff; Rolston, Dennis E; Temple, Steven R; Lee, Juhwan; Six, Johan

    2010-10-01

    Despite the importance of agriculture in California's Central Valley, the potential of alternative management practices to reduce soil greenhouse gas (GHG) emissions has been poorly studied in California. This study aims at (1) calibrating and validating DAYCENT, an ecosystem model, for conventional and alternative cropping systems in California's Central Valley, (2) estimating CO2, N2O, and CH4 soil fluxes from these systems, and (3) quantifying the uncertainty around model predictions induced by variability in the input data. The alternative practices considered were cover cropping, organic practices, and conservation tillage. These practices were compared with conventional agricultural management. The crops considered were beans, corn, cotton, safflower, sunflower, tomato, and wheat. Four field sites, for which at least five years of measured data were available, were used to calibrate and validate the DAYCENT model. The model was able to predict 86-94% of the measured variation in crop yields and 69-87% of the measured variation in soil organic carbon (SOC) contents. A Monte Carlo analysis showed that the predicted variability of SOC contents, crop yields, and N2O fluxes was generally smaller than the measured variability of these parameters, in particular for N2O fluxes. Conservation tillage had the smallest potential to reduce GHG emissions among the alternative practices evaluated, with a significant reduction of the net soil GHG fluxes in two of the three sites of 336 +/- 47 and 550 +/- 123 kg CO2-eq x ha(-1) x yr(-1) (mean +/- SE). Cover cropping had a larger potential, with net soil GHG flux reductions of 752 +/- 10, 1072 +/- 272, and 2201 +/- 82 kg CO2-eq x ha(-1) x yr(-1). Organic practices had the greatest potential for soil GHG flux reduction, with 4577 +/- 272 kg CO2-eq x ha(-1) x yr(-1). Annual differences in weather or management conditions contributed more to the variance in annual GHG emissions than soil variability did. We concluded that the

  2. Replacement of the cross-site transfer system liquid waste transport alternatives evaluation, Project W-058

    International Nuclear Information System (INIS)

    This document examines high-/low-level radioactive liquid waste transport alternatives. Radioactive liquid waste will be transported from the 200 West Area to the 200 East Area and within the 200 East Areas for safe storage and disposal. The radioactive waste transport alternatives are the Aboveground Transport System (French LR-56 Cask System [3,800 L (1,000 gal)]), 19,000-L (5,000-gal) trailer tanker system, 75,700-L (20,000-gal) rail tanker system and Underground Transport System (buried pipe [unlimited transfer volume capability]). The evaluation focused on the following areas: initial project cost, operational cost, secondary waste generation, radiation exposure, and final decommissioning. The evaluation was based on the near term (1995 to 2005) estimated volume of 49.509 million L (13.063 million gal) and long term (1995 to 2028) estimated volume of 757.1 million L (200 million gal). The conclusion showed that the buried pipe (Underground Transport System) resulted in the lowest overall total cost for near and long term, the trailer container resulted in the highest total cost for near and long term, and the French truck was operationally impractical and cost prohibitive

  3. Visitor Assessment of the Mandatory Alternative Transportation System at Zion National Park

    Science.gov (United States)

    Mace, Britton L.; Marquit, Joshua D.; Bates, Scott C.

    2013-11-01

    Transportation infrastructure in national parks has historically been designed for the automobile. With more vehicles in the parks, visitors found themselves in circumstances more reminiscent of a city than a park. Traffic jams, overcrowding, illegal parking, horn honking, and idling vehicles became common, creating stress and contributing to air and noise pollution, the very things visitors were hoping to get away from. Park managers began searching for alternatives, including shuttle systems. Many national parks have implemented optional shuttle systems, but relatively few have completely closed roads to vehicles, transporting visitors on mandatory shuttles. Zion National Park instituted a mandatory shuttle system in May 2000 to relieve crowding and congestion in the main canyon and to protect natural resources. Taking a longitudinal approach, attributes of the shuttle (e.g., crowding, accessibility, freedom, efficiency, preference, and success) were assessed with experiential park factors (e.g., scenic beauty, naturalness, solitude, tranquility, air quality, and soundscape) in 2000, 2003, and 2010 by surveying shuttle-riding park visitors. While visitors initially reported a few reservations about the shuttle system, by 2003, the majority rated the system successful. Ratings of all shuttle-related variables, except crowding, improved over the decade. Improvements were greatest for freedom, accessibility, and efficiency. Multiple regression found overall shuttle success to be mediated by preference, freedom, accessibility, efficiency, and comfort. Experiential variables assessing park conditions followed a similar pattern, with improved ratings as the decade progressed. Results provide important insights into the visitor experience with mandatory alternative shuttle systems in national parks.

  4. Madagascar: A pacemaker for the Agulhas Current system?

    Science.gov (United States)

    Penven, P.; Lutjeharms, J. R. E.; Florenchie, P.

    2006-09-01

    Western boundary currents are driven by zonally integrated wind-stress curl over the width of subtropical basins. This cross-basin integration is interrupted in the South Indian Ocean where Madagascar presents a formidable barrier. Nevertheless, a western boundary current has been thought to exist in the Mozambique Channel, the Mozambique Current. Recent observations have however shown that no such current exists and that the flow in the channel instead consists of a train of eddies. Is this western boundary anomaly due to the presence of Madagascar? We have used a primitive equations model to investigate the flow in the South West Indian Ocean as if there were no Madagascar. We show that a normal, continuous western boundary current is then formed that constitutes a continuum with the Agulhas Current. The presence of Madagascar is shown to affect the frequency of inter-ocean exchange events south of Africa.

  5. Generator Systems for Marine Current Turbine Applications: A Comparative Study

    OpenAIRE

    Benelghali, Seifeddine; BENBOUZID, Mohamed; Charpentier, Jean-Frederic

    2012-01-01

    Emerging technologies for marine current turbines are mainly related to works that have been carried out on wind turbines and ship propellers. It is then obvious that many electric generator topologies could be used for marine current turbines. As in the wind turbine context, doubly-fed induction generators and permanent magnet generators seem to be attractive solutions for harnessing the tidal current energy. In this paper, a comparative study between these two generator types is presented a...

  6. Critical Josephson current in ballistic superconductor-graphene systems

    OpenAIRE

    I. Hagymási; Kormányos, A.; Cserti, J.

    2010-01-01

    We calculate the phase, the temperature and the junction length dependence of the supercurrent for ballistic graphene Josephson-junctions. For low temperatures we find non-sinusoidal dependence of the supercurrent on the superconductor phase difference for both short and long junctions. The skewness, which characterizes the deviation of the current-phase relation from a simple sinusoidal one, shows a linear dependence on the critical current for small currents. We discuss the similarities and...

  7. Josephson current in ballistic superconductor-graphene systems

    OpenAIRE

    Hagymasi, Imre; Kormanyos, Andor; Cserti, József

    2010-01-01

    We calculate the phase, the temperature and the junction length dependence of the supercurrent for ballistic graphene Josephson junctions. For low temperatures we find nonsinusoidal dependence of the supercurrent on the superconductor phase difference for both short and long junctions. The skewness, which characterizes the deviaton of the current-phase relation from a simple sinusoidal one, shows a linear dependence on the critical current for small currents. We discuss the similarities and d...

  8. Selective confinement of vibrations in composite systems with alternate quasi-regular sequences

    Energy Technology Data Exchange (ETDEWEB)

    Montalban, A. [Departamento de Ciencia y Tecnologia de Materiales, Division de Optica, Universidad Miguel Hernandez, 03202 Elche (Spain); Velasco, V.R. [Instituto de Ciencia de Materiales de Madrid, CSIC, Sor Juana Ines de la Cruz 3, 28049 Madrid (Spain)]. E-mail: vrvr@icmm.csic.es; Tutor, J. [Departamento de Fisica Aplicada, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Fernandez-Velicia, F.J. [Departamento de Fisica de los Materiales, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia, Senda del Rey 9, 28080 Madrid (Spain)

    2007-01-01

    We have studied the atom displacements and the vibrational frequencies of 1D systems formed by combinations of Fibonacci, Thue-Morse and Rudin-Shapiro quasi-regular stacks and their alternate ones. The materials are described by nearest-neighbor force constants and the corresponding atom masses, particularized to the Al, Ag systems. These structures exhibit differences in the frequency spectrum as compared to the original simple quasi-regular generations but the most important feature is the presence of separate confinement of the atom displacements in one of the sequences forming the total composite structure for different frequency ranges.

  9. Selective confinement of vibrations in composite systems with alternate quasi-regular sequences

    International Nuclear Information System (INIS)

    We have studied the atom displacements and the vibrational frequencies of 1D systems formed by combinations of Fibonacci, Thue-Morse and Rudin-Shapiro quasi-regular stacks and their alternate ones. The materials are described by nearest-neighbor force constants and the corresponding atom masses, particularized to the Al, Ag systems. These structures exhibit differences in the frequency spectrum as compared to the original simple quasi-regular generations but the most important feature is the presence of separate confinement of the atom displacements in one of the sequences forming the total composite structure for different frequency ranges

  10. Gasification/combined-cycle power generation: environmental assessment of alternative systems

    Energy Technology Data Exchange (ETDEWEB)

    1978-11-01

    This report provides a basis for the comparative assessment of the potential performance capability, technological development, and economic and environmental impact associated with the operation of integrated low-Btu coal-gasification/combined-cycle power systems. Characterization of the integrated power system in terms of fuel processing, power production, and auxiliary systems is followed up with comparisons of alternative integrated-plant-design/fuel combinations with reference to the conventional coal-fired power plant, taking into account both economic and environmental factors. The report includes an assessment of the effects of recent regulatory changes on the prospects for integrated power systems and establishes a timetable for the probable commercial development of such systems by the utilities.

  11. Bioactive forage and phytotherapy to cure and control endo-parasite diseases in sheep and goat farming systems – a review of current scientific knowledge

    OpenAIRE

    Rahmann, Gerold (Ed.); Seip, Hannah

    2007-01-01

    Infestation with gastro-intestinal nematodes (GIN) in small ruminants can cause severe economic losses and endanger animal welfare. The development of organic farming systems, the increased public awareness for drug residues in agricultural products and the development of resistant strains of parasites have enforced the search for sustainable alternatives. The aim of this review is to summarise the current scientific knowledge of alternative strategies to prevent and control endo-parasiti...

  12. Algorithm of Alternating Current Schedule Power Flow for Bulk Interconnected Grid%大型互联电网交流计划潮流算法

    Institute of Scientific and Technical Information of China (English)

    丁平; 李亚楼; 田芳; 李柏青; 严剑峰; 于之虹; 周孝信; 罗志强

    2014-01-01

    In China Power Grid, calculation of alternating current schedule power flow is an important foundation for checking security of schedule. An algorithm of AC schedule power flow applied to bulk interconnected power system was put forward in this paper. The principle of calculating was set firstly, which include four points, namely faithfulness, diversity by area, reality, selectable. Then solution based on interfaces controlling method was given. An approach to active schedule step by step was offered with three means of distributing unbalance power. To regulate reactive power, a method taking advantage of react power arranged in similar power flow was employed, which included using voltage of similar power flow as initial and determining parameter variation referring to closeness between active power of schedule and similar power flow. The algorithm was validated by cases from IEEE 39-node and China State Grid. The algorithm proposed is convergent well, can give power flow close to schedule data and situation appearing in power system, and owns good value for popularization and application.%在中国电网,交流计划潮流计算是校核计划安全性的重要基础。该文提出适用于大型互联电网的交流计划潮流算法。首先确立计算必须遵循的忠实性、分区域、真实性和可选择等4个原则;然后给出基于多断面控制法的实现方案。提出分阶段逐步逼近有功计划的方法,并给出3种不同的不平衡功率分配方式;提出以相似潮流中无功分布为初值并根据有功潮流相似度决定参数变化范围的无功调整方法。所提算法的有效性用 IEEE 39节点和中国国家电网的算例进行了验证。所提算法收敛性强,能给出与计划值和电网实际情况高度接近的潮流结果,具有良好的推广应用价值。

  13. Dynamical Localization in an Asymmetric Two-Electron Quantum Dot Molecule by an Alternating-Current Electric Field

    Institute of Scientific and Technical Information of China (English)

    LIU Yu-Shen; CHEN Hao

    2004-01-01

    @@ We investigate the dynamics of two interacting electrons in an asymmetric double coupled quantum dot under an ac electric field. The numerical results demonstrate that dynamical localization and Rabi oscillation still exist in such a system under the stronger electron correlation. The two electrons can be regarded as a quasiparticle,which move together between two dots similarly to a boson. The dynamics of two electrons in such a quantum system are mainly confined in a Q subspace, which is constructed by two double-occupied states.

  14. Comparison of Soil Respiration in Typical Conventional and New Alternative Cereal Cropping Systems on the North China Plain

    OpenAIRE

    Gao, B; Ju, X.T.; Su, F; Gao, F. B.; Q. S. Cao; Oenema, O.; P. Christie; Chen, X. P.; F. S. Zhang

    2013-01-01

    We monitored soil respiration (Rs), soil temperature (T) and volumetric water content (VWC%) over four years in one typical conventional and four alternative cropping systems to understand Rs in different cropping systems with their respective management practices and environmental conditions. The control was conventional double-cropping system (winter wheat and summer maize in one year - Con. W/M). Four alternative cropping systems were designed with optimum water and N management, i.e. opti...

  15. Evaluating energy-system alternatives in the context of sustainable development

    International Nuclear Information System (INIS)

    Growing awareness of the negative social, environmental and economic impacts caused by the production, distribution and end-use consumption of energy has led the search for alternatives to become increasingly urgent and complex. The need for analytical methods and tools for evaluating options and opportunities is particularly acute in rapidly developing countries. The aim of this article is to illustrate the broad range of issues and impacts that are important for evaluating and comparing energy-system alternatives in the context of sustainable development. The feasibility of producing and utilizing biomass-based ethanol as an alternative transportation fuel in Thailand is explored herein to provide examples and a forum for discussion of these issues. Scenarios describe the conditions under which a significant potential for fuel-switching to domestically-produced ethanol appears to exist. Harnessing this potential could lead to important improvements in the energy system's impacts on human health, Thailand's economy, and the environment. Achieving these improvements, however, would require comprehensive and long-term planning and support on the part of the Thai government

  16. Comparison of Alternatives to the 2004 Vacuum Vessel Heat Transfer System

    Energy Technology Data Exchange (ETDEWEB)

    Yoder Jr, Graydon L [ORNL; Carbajo, Juan J [ORNL; Kim, Seokho H [ORNL

    2010-12-01

    A study comparing different alternatives for the Vacuum Vessel Primary Heat Transfer System has been completed. Three alternatives were proposed in a Project Change Request (PCR-190) by relocating the heat exchangers (HXs) from the roof of the Tokamak building to inside the Vacuum Vessel Pressure Suppression System (VVPSS) tank. The study evaluated the three alternatives and recommended modifications to one of them to arrive at a preferred configuration that included relocating the HXs inside the Tokamak building but outside the VVPSS tank as well as including a small safety-rated pump and HX in parallel to the main circulation pump and HX. The Vacuum Vessel (VV) Primary Heat Transfer System (PHTS) removes heat generated in the VV during normal operation (10 MW, pulsed power) as well as the decay heat from the VV itself and from the structures/components attached to the VV (first wall, blanket, and divertor {approx}0.48 MW peak). Therefore, the VV PHTS has two safety functions: (1) contain contaminated cooling water (similar to the other PHTSs) and (2) provide passive cooling during an accident event. The 2004 design of the VV PHTS consists of two independent loops, each loop cooling half of the 18 VV segments with a nominal flow of 475 kg/s of water at about 1.1 MPa and 100 C. The total flow for both loops is 950 kg/s. Both loops are required to remove the heat load during normal plasma operation. During accident conditions, only one loop is needed to remove by natural convection (no pump needed) the decay heat of the complete VV and attached components. The heat is transferred to heat exchanger (HXs) located on top of the roof, outside the Tokamak building. These HXs are air-to-water (A/W) HXs. Three alternatives have been proposed for this cooling system. For a detailed discussion of these alternatives, please refer to Project Change Request, PCR-190 (Ref. 1). A brief introduction is given here. Alternative 1 includes only one main forced circulation loop with a

  17. Fault current analysis in JT-60 grounding system

    International Nuclear Information System (INIS)

    The determination of a ground fault current is described in the case where a ground fault occurs in JT-60 device. Specifically, a case in which six coils caused a simultaneous ground fault is investigated. It is found that when faults in vertical and toroidal magnetic field coils occur simultaneously, the resultant ground fault current is very large

  18. Waste management facility accident analysis (WASTE ACC) system: software for analysis of waste management alternatives

    International Nuclear Information System (INIS)

    This paper describes the Waste Management Facility Accident Analysis (WASTEunderscoreACC) software, which was developed at Argonne National Laboratory (ANL) to support the US Department of Energy's (DOE's) Waste Management (WM) Programmatic Environmental Impact Statement (PEIS). WASTEunderscoreACC is a decision support and database system that is compatible with Microsoft reg-sign Windows trademark. It assesses potential atmospheric releases from accidents at waste management facilities. The software provides the user with an easy-to-use tool to determine the risk-dominant accident sequences for the many possible combinations of process technologies, waste and facility types, and alternative cases described in the WM PEIS. In addition, its structure will allow additional alternative cases and assumptions to be tested as part of the future DOE programmatic decision-making process. The WASTEunderscoreACC system demonstrates one approach to performing a generic, systemwide evaluation of accident risks at waste management facilities. The advantages of WASTEunderscoreACC are threefold. First, the software gets waste volume and radiological profile data that were used to perform other WM PEIS-related analyses directly from the WASTEunderscoreMGMT system. Second, the system allows for a consistent analysis across all sites and waste streams, which enables decision makers to understand more fully the trade-offs among various policy options and scenarios. Third, the system is easy to operate; even complex scenario runs are completed within minutes

  19. Alternate transmission relaying based on interference alignment in 3-relay half-duplex MIMO systems

    KAUST Repository

    Park, Seongho

    2012-09-01

    In a half-duplex relaying, the capacity pre-log factor 1/2 is a major drawback in spectral efficiency. This paper proposes a linear precoding/decoding scheme and an alternate relaying protocol in a dual-hop half-duplex system where three relays help the communication between the source and the destination. In our proposed scheme, we consider a phase incoherent method in relays in which the source alternately transmits message signals to the different relays. In addition, we propose a linear interference alignment scheme which can suppress the inter-relay interference resulting from the phase incoherence of relaying. Based on our analysis of degrees of freedom and our simulation results, we show that our proposed scheme achieves additional degrees of freedom compared to the conventional half-duplex relaying. © 2012 IEEE.

  20. Alternatives for high-level waste forms, containers, and container processing systems

    International Nuclear Information System (INIS)

    This study evaluates alternatives for high-level waste forms, containers, container processing systems, and onsite interim storage. Glass waste forms considered are cullet, marbles, gems, and monolithic glass. Small and large containers configured with several combinations of overpack confinement and shield casks are evaluated for these waste forms. Onsite interim storage concepts including canister storage building, bore holes, and storage pad were configured with various glass forms and canister alternatives. All favorable options include the monolithic glass production process as the waste form. Of the favorable options the unshielded 4- and 7-canister overpack options have the greatest technical assurance associated with their design concepts due to their process packaging and storage methods. These canisters are 0.68 m and 0.54 m in diameter respectively and 4.57 m tall. Life-cycle costs are not a discriminating factor in most cases, varying typically less than 15 percent