WorldWideScience

Sample records for global electric circuit

  1. A Global Electric Circuit on Mars

    Science.gov (United States)

    Delory, G. T.; Farrell, W. M.; Desch, M. D.

    2001-01-01

    We describe conditions on the surface of Mars conducive to the formation of a martian global electric circuit, in a direct analogy to the terrestrial case where atmospheric currents and electric fields are generated worldwide through the charging in thunderstorms. Additional information is contained in the original extended abstract.

  2. The atmospheric electric global circuit. [thunderstorm activity

    Science.gov (United States)

    Kasemir, H. W.

    1979-01-01

    The hypothesis that world thunderstorm activity represents the generator for the atmospheric electric current flow in the earth atmosphere between ground and the ionosphere is based on a close correlation between the magnitude and the diurnal variation of the supply current (thunderstorm generator current) and the load current (fair weather air-earth current density integrated over the earth surface). The advantages of using lightning survey satellites to furnish a base for accepting or rejecting the thunderstorm generator hypothesis are discussed.

  3. Comment on 'Current Budget of the Atmospheric Electric Global Circuit'

    Science.gov (United States)

    Driscoll, Kevin T.; Blakeslee, Richard J.

    1996-01-01

    In this paper, three major issues relevant to Kasemir's new model will be addressed. The first concerns Kasemir's assertion that there are significant differences between the potentials associated with the new model and the conventional model. A recalculation of these potentials reveals that both models provide equivalent results for the potential difference between the Earth and ionosphere. The second issue to be addressed is Kasemir's assertion that discrepancies in the electric potentials associated with both models can be attributed to modeling the Earth as a sphere, instead of as a planar surface. A simple analytical comparison will demonstrate that differences in the equations for the potentials of the atmosphere derived with a spherical and a planar Earth are negligible for applications to global current flow. Finally, the third issue to be discussed is Kasemir's claim that numerous aspects of the conventional model are incorrect, including the role of the ionosphere in global current flow as well as the significance of cloud-to-ground lightning in supplying charge to the global circuit. In order to refute these misconceptions, it will be shown that these aspects related to the flow of charge in the atmosphere are accurately described by the conventional model of the global circuit.

  4. Coupling of magnetospheric electrical effects into the global atmospheric electrical circuit

    International Nuclear Information System (INIS)

    Hays, P.B.; Roble, R.G.

    1979-01-01

    A quasi-static model of global atmospheric electricity has been constructed (Hays and Roble, 1978) to study the electrical processes in the lower atmosphere and the coupling between solar- and upper- atmosphere-induced variations superimposed upon the global electrical circuit. The paper reviews the essential features of this model and discusses the results obtained thus far on the effects of magnetospheric convection and substorms on the global atmospheric electrical circuit. A schematic diagram of the global quasi-static model is given. It is assumed that thunderstorms act as dipole generators, each with a positive center at the top of the cloud and a negative center a few kilometers lower than the positive center

  5. Global Electric Circuit Diurnal Variation Derived from Storm Overflight and Satellite Optical Lightning Datasets

    Science.gov (United States)

    Mach, Douglas M.; Blakeslee, R. J.; Bateman, M. J.; Bailey, J. C.

    2011-01-01

    We have combined analyses of over 1000 high altitude aircraft observations of electrified clouds with diurnal lightning statistics from the Lightning Imaging Sensor (LIS) and Optical Transient Detector (OTD) to produce an estimate of the diurnal variation in the global electric circuit. Using basic assumptions about the mean storm currents as a function of flash rate and location, and the global electric circuit, our estimate of the current in the global electric circuit matches the Carnegie curve diurnal variation to within 4% for all but two short periods of time. The agreement with the Carnegie curve was obtained without any tuning or adjustment of the satellite or aircraft data. Mean contributions to the global electric circuit from land and ocean thunderstorms are 1.1 kA (land) and 0.7 kA (ocean). Contributions to the global electric circuit from ESCs are 0.22 kA for ocean storms and 0.04 kA for land storms. Using our analysis, the mean total conduction current for the global electric circuit is 2.0 kA.

  6. In situ measurements of contributions to the global electrical circuit by a thunderstorm in southeastern Brazil

    Science.gov (United States)

    Thomas, J.N.; Holzworth, R.H.; McCarthy, M.P.

    2009-01-01

    The global electrical circuit, which maintains a potential of about 280??kV between the earth and the ionosphere, is thought to be driven mainly by thunderstorms and lightning. However, very few in situ measurements of electrical current above thunderstorms have been successfully obtained. In this paper, we present dc to very low frequency electric fields and atmospheric conductivity measured in the stratosphere (30-35??km altitude) above an active thunderstorm in southeastern Brazil. From these measurements, we estimate the mean quasi-static conduction current during the storm period to be 2.5 ?? 1.25??A. Additionally, we examine the transient conduction currents following a large positive cloud-to-ground (+ CG) lightning flash and typical - CG flashes. We find that the majority of the total current is attributed to the quasi-static thundercloud charge, rather than lightning, which supports the classical Wilson model for the global electrical circuit.

  7. Global Electric Circuit Implications of Total Current Measurements over Electrified Clouds

    Science.gov (United States)

    Mach, Douglas M.; Blakeslee, Richard J.; Bateman, Monte G.

    2009-01-01

    We determined total conduction (Wilson) currents and flash rates for 850 overflights of electrified clouds spanning regions including the Southeastern United States, the Western Atlantic Ocean, the Gulf of Mexico, Central America and adjacent oceans, Central Brazil, and the South Pacific. The overflights include storms over land and ocean, with and without lightning, and with positive and negative Wilson currents. We combined these individual storm overflight statistics with global diurnal lightning variation data from the Lightning Imaging Sensor (LIS) and Optical Transient Detector (OTD) to estimate the thunderstorm and electrified shower cloud contributions to the diurnal variation in the global electric circuit. The contributions to the global electric circuit from lightning producing clouds are estimated by taking the mean current per flash derived from the overflight data for land and ocean overflights and combining it with the global lightning rates (for land and ocean) and their diurnal variation derived from the LIS/OTD data. We estimate the contribution of non-lightning producing electrified clouds by assuming several different diurnal variations and total non-electrified storm counts to produce estimates of the total storm currents (lightning and non-lightning producing storms). The storm counts and diurnal variations are constrained so that the resultant total current diurnal variation equals the diurnal variation in the fair weather electric field (+/-15%). These assumptions, combined with the airborne and satellite data, suggest that the total mean current in the global electric circuit ranges from 2.0 to 2.7 kA, which is greater than estimates made by others using other methods.

  8. The global atmospheric electric circuit and its effects on cloud microphysics

    International Nuclear Information System (INIS)

    Tinsley, B A

    2008-01-01

    This review is an overview of progress in understanding the theory and observation of the global atmospheric electric circuit, with the focus on its dc aspects, and its short and long term variability. The effects of the downward ionosphere-earth current density, J z , on cloud microphysics, with its variability as an explanation for small observed changes in weather and climate, will also be reviewed. The global circuit shows responses to external as well as internal forcing. External forcing arises from changes in the distribution of conductivity due to changes in the cosmic ray flux and other energetic space particle fluxes, and at high magnetic latitudes from solar wind electric fields. Internal forcing arises from changes in the generators and changes in volcanic and anthropogenic aerosols in the troposphere and stratosphere. All these result in spatial and temporal variation in J z . Variations in J z affect the production of space charge in layer clouds, with the charges being transferred to droplets and aerosol particles. New observations and new analyses are consistent with non-negligible effects of the charges on the microphysics of such clouds. Observed effects are small, but of high statistical significance for cloud cover and precipitation changes, with resulting atmospheric temperature, pressure and dynamics changes. These effects are detectable on the day-to-day timescale for repeated J z changes of order 10%, and are thus second order electrical effects. The implicit first order effects have not, as yet, been incorporated into basic cloud and aerosol physics. Long term (multidecadal through millennial) global circuit changes, due to solar activity modulating the galactic cosmic ray flux, are an order of magnitude greater at high latitudes and in the stratosphere, as can be inferred from geological cosmogenic isotope records. Proxies for climate change in the same stratified depositories show strong correlations of climate with the inferred global

  9. The global atmospheric electric circuit and its effects on cloud microphysics

    Energy Technology Data Exchange (ETDEWEB)

    Tinsley, B A [Physics Department and Center for Space Sciences, WT15, University of Texas at Dallas, 800 W Campbell Road, Richardson, TX, 75080-3021 (United States)], E-mail: Tinsley@UTDallas.edu

    2008-06-15

    This review is an overview of progress in understanding the theory and observation of the global atmospheric electric circuit, with the focus on its dc aspects, and its short and long term variability. The effects of the downward ionosphere-earth current density, J{sub z}, on cloud microphysics, with its variability as an explanation for small observed changes in weather and climate, will also be reviewed. The global circuit shows responses to external as well as internal forcing. External forcing arises from changes in the distribution of conductivity due to changes in the cosmic ray flux and other energetic space particle fluxes, and at high magnetic latitudes from solar wind electric fields. Internal forcing arises from changes in the generators and changes in volcanic and anthropogenic aerosols in the troposphere and stratosphere. All these result in spatial and temporal variation in J{sub z}. Variations in J{sub z} affect the production of space charge in layer clouds, with the charges being transferred to droplets and aerosol particles. New observations and new analyses are consistent with non-negligible effects of the charges on the microphysics of such clouds. Observed effects are small, but of high statistical significance for cloud cover and precipitation changes, with resulting atmospheric temperature, pressure and dynamics changes. These effects are detectable on the day-to-day timescale for repeated J{sub z} changes of order 10%, and are thus second order electrical effects. The implicit first order effects have not, as yet, been incorporated into basic cloud and aerosol physics. Long term (multidecadal through millennial) global circuit changes, due to solar activity modulating the galactic cosmic ray flux, are an order of magnitude greater at high latitudes and in the stratosphere, as can be inferred from geological cosmogenic isotope records. Proxies for climate change in the same stratified depositories show strong correlations of climate with the

  10. Analysis of the Diurnal Variation of the Global Electric Circuit Obtained From Different Numerical Models

    Science.gov (United States)

    Jánský, Jaroslav; Lucas, Greg M.; Kalb, Christina; Bayona, Victor; Peterson, Michael J.; Deierling, Wiebke; Flyer, Natasha; Pasko, Victor P.

    2017-12-01

    This work analyzes different current source and conductivity parameterizations and their influence on the diurnal variation of the global electric circuit (GEC). The diurnal variations of the current source parameterizations obtained using electric field and conductivity measurements from plane overflights combined with global Tropical Rainfall Measuring Mission satellite data give generally good agreement with measured diurnal variation of the electric field at Vostok, Antarctica, where reference experimental measurements are performed. An approach employing 85 GHz passive microwave observations to infer currents within the GEC is compared and shows the best agreement in amplitude and phase with experimental measurements. To study the conductivity influence, GEC models solving the continuity equation in 3-D are used to calculate atmospheric resistance using yearly averaged conductivity obtained from the global circulation model Community Earth System Model (CESM). Then, using current source parameterization combining mean currents and global counts of electrified clouds, if the exponential conductivity is substituted by the conductivity from CESM, the peak to peak diurnal variation of the ionospheric potential of the GEC decreases from 24% to 20%. The main reason for the change is the presence of clouds while effects of 222Rn ionization, aerosols, and topography are less pronounced. The simulated peak to peak diurnal variation of the electric field at Vostok is increased from 15% to 18% from the diurnal variation of the global current in the GEC if conductivity from CESM is used.

  11. Global Electric Circuit Implications of Combined Aircraft Storm Electric Current Measurements and Satellite-Based Diurnal Lightning Statistics

    Science.gov (United States)

    Mach, Douglas M.; Blakeslee, Richard J.; Bateman, Monte G.

    2011-01-01

    Using rotating vane electric field mills and Gerdien capacitors, we measured the electric field profile and conductivity during 850 overflights of thunderstorms and electrified shower clouds (ESCs) spanning regions including the Southeastern United States, the Western Atlantic Ocean, the Gulf of Mexico, Central America and adjacent oceans, Central Brazil, and the South Pacific. The overflights include storms over land and ocean, and with positive and negative fields above the storms. Over three-quarters (78%) of the land storms had detectable lightning, while less than half (43%) of the oceanic storms had lightning. Integrating our electric field and conductivity data, we determined total conduction currents and flash rates for each overpass. With knowledge of the storm location (land or ocean) and type (with or without lightning), we determine the mean currents by location and type. The mean current for ocean thunderstorms is 1.7 A while the mean current for land thunderstorms is 1.0 A. The mean current for ocean ESCs 0.41 A and the mean current for land ESCs is 0.13 A. We did not find any significant regional or latitudinal based patterns in our total conduction currents. By combining the aircraft derived storm currents and flash rates with diurnal flash rate statistics derived from the Lightning Imaging Sensor (LIS) and Optical Transient Detector (OTD) low Earth orbiting satellites, we reproduce the diurnal variation in the global electric circuit (i.e., the Carnegie curve) to within 4% for all but two short periods of time. The agreement with the Carnegie curve was obtained without any tuning or adjustment of the satellite or aircraft data. Given our data and assumptions, mean contributions to the global electric circuit are 1.1 kA (land) and 0.7 kA (ocean) from thunderstorms, and 0.22 kA (ocean) and 0.04 (land) from ESCs, resulting in a mean total conduction current estimate for the global electric circuit of 2.0 kA. Mean storm counts are 1100 for land

  12. Simulation of the Universal-Time Diurnal Variation of the Global Electric Circuit Charging Rate

    Science.gov (United States)

    Mackerras, D.; Darvenzia, M.; Orville, R. E.; Williams, E. R.; Goodman, S. J.

    1999-01-01

    A global lightning model that includes diurnal and annual lightning variation, and total flash density versus latitude for each major land and ocean, has been used as the basis for simulating the global electric circuit charging rate. A particular objective has been to reconcile the difference in amplitude ratios [AR=(max-min)/mean] between global lightning diurnal variation (AR approx. = 0.8) and the diurnal variation of typical atmospheric potential gradient curves (AR approx. = 0.35). A constraint on the simulation is that the annual mean charging current should be about 1000 A. The global lightning model shows that negative ground flashes can contribute, at most, about 10-15% of the required current. For the purpose of the charging rate simulation, it was assumed that each ground flash contributes 5 C to the charging process. It was necessary to assume that all electrified clouds contribute to charging by means other than lightning, that the total flash rate can serve as an indirect indicator of the rate of charge transfer, and that oceanic electrified clouds contribute to charging even though they are relatively inefficient in producing lightning. It was also found necessary to add a diurnally invariant charging current component. By trial and error it was found that charging rate diurnal variation curves in Universal time (UT) could be produced with amplitude ratios and general shapes similar to those of the potential gradient diurnal variation curves measured over ocean and arctic regions during voyages of the Carnegie Institute research vessels.

  13. A TRMM/GPM retrieval of the total mean generator current for the global electric circuit

    Science.gov (United States)

    Peterson, Michael; Deierling, Wiebke; Liu, Chuntao; Mach, Douglas; Kalb, Christina

    2017-09-01

    A specialized satellite version of the passive microwave electric field retrieval algorithm (Peterson et al., 2015) is applied to observations from the Tropical Rainfall Measuring Mission (TRMM) and Global Precipitation Measurement (GPM) satellites to estimate the generator current for the Global Electric Circuit (GEC) and compute its temporal variability. By integrating retrieved Wilson currents from electrified clouds across the globe, we estimate a total mean current of between 1.4 kA (assuming the 7% fraction of electrified clouds producing downward currents measured by the ER-2 is representative) to 1.6 kA (assuming all electrified clouds contribute to the GEC). These current estimates come from all types of convective weather without preference, including Electrified Shower Clouds (ESCs). The diurnal distribution of the retrieved generator current is in excellent agreement with the Carnegie curve (RMS difference: 1.7%). The temporal variability of the total mean generator current ranges from 110% on semi-annual timescales (29% on an annual timescale) to 7.5% on decadal timescales with notable responses to the Madden-Julian Oscillation and El Nino Southern Oscillation. The geographical distribution of current includes significant contributions from oceanic regions in addition to the land-based tropical chimneys. The relative importance of the Americas and Asia chimneys compared to Africa is consistent with the best modern ground-based observations and further highlights the importance of ESCs for the GEC.

  14. Electric circuits essentials

    CERN Document Server

    REA, Editors of

    2012-01-01

    REA's Essentials provide quick and easy access to critical information in a variety of different fields, ranging from the most basic to the most advanced. As its name implies, these concise, comprehensive study guides summarize the essentials of the field covered. Essentials are helpful when preparing for exams, doing homework and will remain a lasting reference source for students, teachers, and professionals. Electric Circuits I includes units, notation, resistive circuits, experimental laws, transient circuits, network theorems, techniques of circuit analysis, sinusoidal analysis, polyph

  15. Combined Aircraft and Satellite-Derived Storm Electric Current and Lightning Rates Measurements and Implications for the Global Electric Circuit

    Science.gov (United States)

    Mach, Douglas M.; Blakeslee, Richard J.; Bateman, Monte G.

    2010-01-01

    Using rotating vane electric field mills and Gerdien capacitors, we measured the electric field profile and conductivity during 850 overflights of electrified shower clouds and thunderstorms spanning regions including the Southeastern United States, the Western Atlantic Ocean, the Gulf of Mexico, Central America and adjacent oceans, Central Brazil, and the South Pacific. The overflights include storms over land and ocean, with and without lightning, and with positive and negative fields above the storms. The measurements were made with the NASA ER-2 and the Altus-II high altitude aircrafts. Peak electric fields, with lightning transients removed, ranged from -1.0 kV/m to 16 kV/m, with a mean value of 0.9 kV/m. The median peak field was 0.29 kV/m. Integrating our electric field and conductivity data, we determined total conduction currents and flash rates for each overpass. With knowledge of the storm location (land or ocean) and type (with or without lightning), we determine the mean currents by location and type. The mean current for ocean storms with lightning is 1.6 A while the mean current for land storms with lightning is 1.0 A. The mean current for oceanic storms without lightning (i.e., electrified shower clouds) is 0.39 A and the mean current for land storms without lightning is 0.13 A. Thus, on average, land storms with or without lightning have about half the mean current as their corresponding oceanic storm counterparts. Over three-quarters (78%) of the land storms had detectable lightning, while less than half (43%) of the oceanic storms had lightning. We did not find any significant regional or latitudinal based patterns in our total conduction currents. By combining the aircraft derived storm currents and flash rates with diurnal lightning statistics derived from the Lightning Imaging Sensor (LIS) and Optical Transient Detector (OTD) low Earth orbiting satellites, we reproduce the diurnal variation in the global electric circuit (i.e., the Carnegie

  16. Electrical Circuits and Water Analogies

    Science.gov (United States)

    Smith, Frederick A.; Wilson, Jerry D.

    1974-01-01

    Briefly describes water analogies for electrical circuits and presents plans for the construction of apparatus to demonstrate these analogies. Demonstrations include series circuits, parallel circuits, and capacitors. (GS)

  17. Electric circuits and signals

    CERN Document Server

    Sabah, Nassir H

    2007-01-01

    Circuit Variables and Elements Overview Learning Objectives Electric Current Voltage Electric Power and Energy Assigned Positive Directions Active and Passive Circuit Elements Voltage and Current Sources The Resistor The Capacitor The Inductor Concluding Remarks Summary of Main Concepts and Results Learning Outcomes Supplementary Topics on CD Problems and Exercises Basic Circuit Connections and Laws Overview Learning Objectives Circuit Terminology Kirchhoff's Laws Voltage Division and Series Connection of Resistors Current Division and Parallel Connection of Resistors D-Y Transformation Source Equivalence and Transformation Reduced-Voltage Supply Summary of Main Concepts and Results Learning Outcomes Supplementary Topics and Examples on CD Problems and Exercises Basic Analysis of Resistive Circuits Overview Learning Objectives Number of Independent Circuit Equations Node-Voltage Analysis Special Considerations in Node-Voltage Analysis Mesh-Current Analysis Special Conside...

  18. Time dependent charging of layer clouds in the global electric circuit

    Science.gov (United States)

    Zhou, Limin; Tinsley, Brian A.

    2012-09-01

    There is much observational data consistent with the hypothesis that the ionosphere-earth current density (Jz) in the global electric circuit, which is modulated by both solar activity and thunderstorm activity, affects atmospheric dynamics and cloud cover. One candidate mechanism involves Jz causing the accumulation of space charge on droplets and aerosol particles, that affects the rate of scavenging of the latter, notably those of Cloud Condensation Nuclei (CCN) and Ice Forming Nuclei (IFN) (Tinsley, 2008, 2010). Space charge is the difference, per unit volume, between total positive and total negative electrical charge that is on droplets, aerosol particles (including the CCN and IFN) and air ions. The cumulative effects of the scavenging in stratiform clouds and aerosol layers in an air mass over the lifetime of the aerosol particles of 1-10 days affects the concentration and size distribution of the CCN, so that in subsequent episodes of cloud formation (including deep convective clouds) there can be effects on droplet size distribution, coagulation, precipitation processes, and even storm dynamics.Because the time scales for charging for some clouds can be long compared to cloud lifetimes, the amount of charge at a given time, and its effect on scavenging, depend more on the charging rate than on the equilibrium charge that would eventually be attained. To evaluate this, a new time-dependent charging model has been developed. The results show that for typical altostratus clouds with typical droplet radii 10 μm and aerosol particles of radius of 0.04 μm, the time constant for charging in response to a change in Jz is about 800 s, which is comparable to cloud formation and dissipation timescales for some cloud situations. The charging timescale is found to be strong functions of altitude and aerosol concentration, with the time constant for droplet charging at 2 km in air with a high concentration of aerosols being about an hour, and for clouds at 10 km in

  19. Electric circuits problem solver

    CERN Document Server

    REA, Editors of

    2012-01-01

    Each Problem Solver is an insightful and essential study and solution guide chock-full of clear, concise problem-solving gems. All your questions can be found in one convenient source from one of the most trusted names in reference solution guides. More useful, more practical, and more informative, these study aids are the best review books and textbook companions available. Nothing remotely as comprehensive or as helpful exists in their subject anywhere. Perfect for undergraduate and graduate studies.Here in this highly useful reference is the finest overview of electric circuits currently av

  20. Electric circuit theory applied electricity and electronics

    CERN Document Server

    Yorke, R

    1981-01-01

    Electric Circuit Theory provides a concise coverage of the framework of electrical engineering. Comprised of six chapters, this book emphasizes the physical process of electrical engineering rather than abstract mathematics. Chapter 1 deals with files, circuits, and parameters, while Chapter 2 covers the natural and forced response of simple circuit. Chapter 3 talks about the sinusoidal steady state, and Chapter 4 discusses the circuit analysis. The fifth chapter tackles frequency response of networks, and the last chapter covers polyphase systems. This book will be of great help to electrical

  1. New model simulations of the global atmospheric electric circuit driven by thunderstorms and electrified shower clouds: The roles of lightning and sprites

    DEFF Research Database (Denmark)

    Rycroft, Michael J.; Odzimek, Anna; Arnold, Neil F.

    2007-01-01

    discharge from the base of a thunderstorm increases the ionospheric potential above the thundercloud by 0.0013%. Assuming the ionosphere to be an equipotential surface, this discharge increases the current flowing in the global circuit and the fair-weather electric field also by 0.0013%. A moderate positive...

  2. Variational integrators for electric circuits

    International Nuclear Information System (INIS)

    Ober-Blöbaum, Sina; Tao, Molei; Cheng, Mulin; Owhadi, Houman; Marsden, Jerrold E.

    2013-01-01

    In this contribution, we develop a variational integrator for the simulation of (stochastic and multiscale) electric circuits. When considering the dynamics of an electric circuit, one is faced with three special situations: 1. The system involves external (control) forcing through external (controlled) voltage sources and resistors. 2. The system is constrained via the Kirchhoff current (KCL) and voltage laws (KVL). 3. The Lagrangian is degenerate. Based on a geometric setting, an appropriate variational formulation is presented to model the circuit from which the equations of motion are derived. A time-discrete variational formulation provides an iteration scheme for the simulation of the electric circuit. Dependent on the discretization, the intrinsic degeneracy of the system can be canceled for the discrete variational scheme. In this way, a variational integrator is constructed that gains several advantages compared to standard integration tools for circuits; in particular, a comparison to BDF methods (which are usually the method of choice for the simulation of electric circuits) shows that even for simple LCR circuits, a better energy behavior and frequency spectrum preservation can be observed using the developed variational integrator

  3. The temperature signature of an IMF-driven change to the global atmospheric electric circuit (GEC) in the Antarctic troposphere

    Science.gov (United States)

    Freeman, Mervyn; Lam, Mai Mai; Chisham, Gareth

    2017-04-01

    We use National Centers for Environmental Prediction (NCEP)/National Center for Atmospheric Research (NCAR) reanalysis data to show that Antarctic surface air temperature anomalies result from differences in the daily-mean duskward component,By, of the interplanetary magnetic field (IMF). We find the anomalies have strong geographical and seasonal variations. Regional anomalies are evident poleward of 60˚ S and are of diminishing representative peak amplitude from autumn (3.2˚ C) to winter (2.4˚ C) to spring (1.6˚ C) to summer (0.9˚ C). We demonstrate that anomalies of statistically-significant amplitude are due to geostrophic wind anomalies, resulting from the same By changes, moving air across large meridional gradients in zonal mean air temperature between 60 and 80˚ S. Additionally, we find that the mean tropospheric temperature anomaly for geographical latitudes ≤ -70˚ peaks at about 0.7 K and is statistically significant at the 1 - 5% level between air pressures of 1000 and 500 hPa (i.e., ˜0.1 to 5.6 km altitude above sea level) and for time lags with respect to the IMF of up to 7 days. The signature propagates vertically between air pressure p ≥ 850 hPa (≤ 1.5 km) and p = 500 hPa (˜5.6 km). The characteristics of prompt response and vertical propagation within the troposphere have previously been seen in the correlation between the IMF and high-latitude air pressure anomalies, known as the Mansurov effect, at higher statistical significances (1%). We conclude that we have identified the temperature signature of the Mansurov effect in the Antarctic troposphere. Since these tropospheric anomalies have been associated with By-driven anomalies in the electric potential of the ionosphere, we further conclude that they are caused by IMF-induced changes to the global atmospheric electric circuit (GEC). Our results support the view that variations in the ionospheric potential act on the troposphere via the action of resulting variations in the

  4. Electric Vehicle Interaction at the Electrical Circuit Level

    Science.gov (United States)

    2018-01-01

    The objective of the Electric Vehicle Interaction at the Electrical Circuit Level project was to investigate electric vehicle (EV) charging as a means of mitigating transient over-voltages (TOVs) on the circuit level electric utility distribution gri...

  5. Project Circuits in a Basic Electric Circuits Course

    Science.gov (United States)

    Becker, James P.; Plumb, Carolyn; Revia, Richard A.

    2014-01-01

    The use of project circuits (a photoplethysmograph circuit and a simple audio amplifier), introduced in a sophomore-level electric circuits course utilizing active learning and inquiry-based methods, is described. The development of the project circuits was initiated to promote enhanced engagement and deeper understanding of course content among…

  6. Dynamic theory for the mesoscopic electric circuit

    International Nuclear Information System (INIS)

    Chen Bin; Shen Xiaojuan; Li Youquan; Sun LiLy; Yin Zhujian

    2005-01-01

    The quantum theory for mesoscopic electric circuit with charge discreteness is briefly described. The minibands of quasienergy in LC design mesoscopic electric circuit have been found. In the mesoscopic 'pure' inductance design circuit, just like in the mesoscopic metallic rings, the quantum dynamic characteristics have been obtained explicitly. In the 'pure' capacity design circuit, the Coulomb blockade had also been addressed

  7. Electrical circuit theory and technology

    CERN Document Server

    Bird, John

    2014-01-01

    This much-loved textbook explains the principles of electrical circuit theory and technology so that students of electrical and mechanical engineering can master the subject. Real-world situations and engineering examples put the theory into context. The inclusion of worked problems with solutions help you to learn and further problems then allow you to test and confirm you have fully understood each subject. In total the book contains 800 worked problems, 1000 further problems and 14 revision tests with answers online. This an ideal text for foundation and undergraduate degree students and those on upper level vocational engineering courses, in particular electrical and mechanical. It provides a sound understanding of the knowledge required by technicians in fields such as electrical engineering, electronics and telecommunications. This edition has been updated with developments in key areas such as semiconductors, transistors, and fuel cells, along with brand new material on ABCD parameters and Fourier's An...

  8. Realizing a supercapacitor in an electrical circuit

    International Nuclear Information System (INIS)

    Fukuhara, Mikio; Kuroda, Tomoyuki; Hasegawa, Fumihiko

    2014-01-01

    Capacitors are commonly used in electronic resonance circuits; however, capacitors have not been used for storing large amounts of electrical energy in electrical circuits. Here, we report a superior RC circuit which serves as an electrical storage system characterized by quick charging and long-term discharging of electricity. The improved energy storage characteristics in this mixed electric circuit (R 1  + R 2 C 1 ) with small resistor R 1 , large resistor R 2 , and large capacitor C 1 are derived from the damming effect by large R 2 in simple parallel R 2 C 1 circuit. However, no research work has been carried out previously on the use of capacitors as electrical energy storage devices in circuits. Combined with nanotechnology, we hope that our finding will play a remarkable role in a variety of applications such as hybrid electric vehicles and backup power supplies

  9. Trip electrical circuit of the gyrotion

    International Nuclear Information System (INIS)

    Rossi, J.O.

    1987-09-01

    The electron cyclotron resonance heating system of INPE/LAP is shown and the trip electrical circuit of the gyrotron is described, together with its fundamental aspects. The trip electrical circuit consists basically of a series regulator circuit which regulates the output voltage level and controls the pulse width time. Besides that, a protection circuit for both tubes, regulator and gyrotron, against faults in the system. (author) [pt

  10. On equivalent resistance of electrical circuits

    Science.gov (United States)

    Kagan, Mikhail

    2015-01-01

    While the standard (introductory physics) way of computing the equivalent resistance of nontrivial electrical circuits is based on Kirchhoff's rules, there is a mathematically and conceptually simpler approach, called the method of nodal potentials, whose basic variables are the values of the electric potential at the circuit's nodes. In this paper, we review the method of nodal potentials and illustrate it using the Wheatstone bridge as an example. We then derive a closed-form expression for the equivalent resistance of a generic circuit, which we apply to a few sample circuits. The result unveils a curious interplay between electrical circuits, matrix algebra, and graph theory and its applications to computer science. The paper is written at a level accessible by undergraduate students who are familiar with matrix arithmetic. Additional proofs and technical details are provided in appendices.

  11. Aging evaluation of electrical circuits using the ECCAD [Electrical Circuit Characterization and Diagnostic] system

    International Nuclear Information System (INIS)

    Edson, J.L.

    1988-01-01

    As a part of the Nuclear Regulatory Commission Nuclear Plant Aging Research Program, an aging assessment of electrical circuits was conducted at the Shippingport Atomic Power Station Decommissioning Project. The objective of this work was to evaluate the effectiveness of the Electrical Circuit Characterization and Diagnostic (ECCAD) system in identifying circuit conditions, to determine the present condition of selected electrical circuits, and correlate the results with aging effects. To accomplish this task, a series of electrical tests was performed on each circuit using the ECCAD system, which is composed of commercially available electronic test equipment under computer control. Test results indicate that the ECCAD system is effective in detecting and identifying aging and service wear in selected electrical circuits. The major area of degradation in the circuits tested was at the termination/connection points, whereas the cables were in generally good condition

  12. Realizing a supercapacitor in an electrical circuit

    Energy Technology Data Exchange (ETDEWEB)

    Fukuhara, Mikio, E-mail: fukuhara@niche.tohoku.ac.jp; Kuroda, Tomoyuki; Hasegawa, Fumihiko [New Industry Creation Hatchery Center, Tohoku University, Sendai 980-8579 (Japan)

    2014-11-17

    Capacitors are commonly used in electronic resonance circuits; however, capacitors have not been used for storing large amounts of electrical energy in electrical circuits. Here, we report a superior RC circuit which serves as an electrical storage system characterized by quick charging and long-term discharging of electricity. The improved energy storage characteristics in this mixed electric circuit (R{sub 1} + R{sub 2}C{sub 1}) with small resistor R{sub 1}, large resistor R{sub 2}, and large capacitor C{sub 1} are derived from the damming effect by large R{sub 2} in simple parallel R{sub 2}C{sub 1} circuit. However, no research work has been carried out previously on the use of capacitors as electrical energy storage devices in circuits. Combined with nanotechnology, we hope that our finding will play a remarkable role in a variety of applications such as hybrid electric vehicles and backup power supplies.

  13. Fuel Cell Equivalent Electric Circuit Parameter Mapping

    DEFF Research Database (Denmark)

    Jeppesen, Christian; Zhou, Fan; Andreasen, Søren Juhl

    In this work a simple model for a fuel cell is investigated for diagnostic purpose. The fuel cell is characterized, with respect to the electrical impedance of the fuel cell at non-faulty conditions and under variations in load current. Based on this the equivalent electrical circuit parameters can...

  14. 29 CFR 1915.181 - Electrical circuits and distribution boards.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Electrical circuits and distribution boards. 1915.181... Electrical Machinery § 1915.181 Electrical circuits and distribution boards. (a) The provisions of this... employee is permitted to work on an electrical circuit, except when the circuit must remain energized for...

  15. Electrical circuit modeling of reversed field pinches

    International Nuclear Information System (INIS)

    Sprott, J.C.

    1988-02-01

    Equations are proposed to describe the radial variation of the magnetic field and current density in a circular, cylindrical RFP. These equations are used to derive the electrical circuit parameters (inductance, resistance, and coupling coefficient) for an RFP discharge. The circuit parameters are used to evaluate the flux and energy consumption for various startup modes and for steady-state operation using oscillating field current drive. The results are applied to the MST device. 32 refs., 14 figs., 1 tab

  16. 30 CFR 75.518 - Electric equipment and circuits; overload and short circuit protection.

    Science.gov (United States)

    2010-07-01

    ... short circuit protection. 75.518 Section 75.518 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... Equipment-General § 75.518 Electric equipment and circuits; overload and short circuit protection... installed so as to protect all electric equipment and circuits against short circuit and overloads. Three...

  17. Chemical Detection using Electrically Open Circuits having no Electrical Connections

    Science.gov (United States)

    Woodward, Stanley E.; Olgesby, Donald M.; Taylor, Bryant D.; Shams, Qamar A.

    2008-01-01

    This paper presents investigations to date on chemical detection using a recently developed method for designing, powering and interrogating sensors as electrically open circuits having no electrical connections. In lieu of having each sensor from a closed circuit with multiple electrically connected components, an electrically conductive geometric pattern that is powered using oscillating magnetic fields and capable of storing an electric field and a magnetic field without the need of a closed circuit or electrical connections is used. When electrically active, the patterns respond with their own magnetic field whose frequency, amplitude and bandwidth can be correlated with the magnitude of the physical quantities being measured. Preliminary experimental results of using two different detection approaches will be presented. In one method, a thin film of a reactant is deposited on the surface of the open-circuit sensor. Exposure to a specific targeted reactant shifts the resonant frequency of the sensor. In the second method, a coating of conductive material is placed on a thin non-conductive plastic sheet that is placed over the surface of the sensor. There is no physical contact between the sensor and the electrically conductive material. When the conductive material is exposed to a targeted reactant, a chemical reaction occurs that renders the material non-conductive. The change in the material s electrical resistance within the magnetic field of the sensor alters the sensor s response bandwidth and amplitude, allowing detection of the reaction without having the reactants in physical contact with the sensor.

  18. Intrinsically safe electrical installations, auxiliary circuits and electric communication equipment

    Energy Technology Data Exchange (ETDEWEB)

    Herms, C D

    1981-11-19

    Technical progress has not stopped short of electrical systems in mining, so that three new chapters are new included in the VDE regulations leaflet No. 0118 on 'Installation of electrical systems in underground coal mining'. The regulations on intrinsically safe electric systems, auxiliary circuits and communication systems are briefly described, and grounds for the regulations are presented. The regulations already take account of European regulations on intrinsic safety which will soon be published in a European Regulation on Mine Explosions. In the chapters on auxiliary circuits and communication systems, protection against direct contact, fires, and explosions is discussed as well as the further goal of reliable signal transmission.

  19. 30 CFR 77.506 - Electric equipment and circuits; overload and short-circuit protection.

    Science.gov (United States)

    2010-07-01

    ... short-circuit protection. 77.506 Section 77.506 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... circuits; overload and short-circuit protection. Automatic circuit-breaking devices or fuses of the correct type and capacity shall be installed so as to protect all electric equipment and circuits against short...

  20. 30 CFR 57.4011 - Abandoned electric circuits.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Abandoned electric circuits. 57.4011 Section 57.4011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... and Control § 57.4011 Abandoned electric circuits. Abandoned electric circuits shall be deenergized...

  1. 30 CFR 77.500 - Electric power circuits and electric equipment; deenergization.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric power circuits and electric equipment... OF UNDERGROUND COAL MINES Electrical Equipment-General § 77.500 Electric power circuits and electric equipment; deenergization. Power circuits and electric equipment shall be deenergized before work is done on...

  2. Influence of Solar Wind on the Global Electric Circuit, and Inferred Effects on Cloud Microphysics, Temperature, and Dynamics in the Troposphere

    Science.gov (United States)

    Tinsley, Brian A.

    2000-11-01

    There are at least three independent ways in which the solar wind modulates the flow of current density (Jz) in the global electric circuit. These are (A) changes in the galactic cosmic ray energy spectrum, (B) changes in the precipitation of relativistic electrons from the magnetosphere, and (C) changes in the ionospheric potential distribution in the polar caps due to magnetosphere-ionosphere coupling. The current density J_z flows between the ionosphere and the surface, and as it passes through conductivity gradients it generates space charge concentrations dependent on J_z and the conductivity gradient. The gradients are large at the surfaces of clouds and space charge concentrations of order 1000 to 10,000 elementary charges per cm^3 can be generated at cloud tops. The charge transfers to droplets, many of which are evaporating at the cloud-clear air interface. The charge remains on the residual evaporation nuclei with a lifetime against leakage of order 1000 sec, and for a longer period the nuclei also retain coatings of sulfate and organic compounds adsorbed by the droplet while in the cloud. The charged evaporation nuclei become well mixed with more droplets in many types of clouds with penetrative mixing. The processes of entrainment and evaporation are also efficient for these clouds. The collection of such nuclei by nearby droplets is greatly increased by the electrical attraction between the charge on the particle and the image charge that it creates on the droplet. This process is called electroscavenging. Because the charge on the evaporation nuclei is derived from the original space charge, it depends on J_z, giving a rate of electroscavenging responsive to the solar wind inputs. There may be a number of ways in which the electroscavenging has consequences for weather and climate. One possibility is enhanced production of ice. The charged evaporation nuclei have been found to be good ice forming nuclei because of their coatings, and so in supercooled

  3. Fractional RC and LC Electrical Circuits

    Directory of Open Access Journals (Sweden)

    Gómez-Aguilar José Francisco

    2014-04-01

    Full Text Available In this paper we propose a fractional differential equation for the electrical RC and LC circuit in terms of the fractional time derivatives of the Caputo type. The order of the derivative being considered is 0 < ɣ ≤1. To keep the dimensionality of the physical parameters R, L, C the new parameter σ is introduced. This parameter characterizes the existence of fractional structures in the system. A relation between the fractional order time derivative ɣ and the new parameter σ is found. The numeric Laplace transform method was used for the simulation of the equations results. The results show that the fractional differential equations generalize the behavior of the charge, voltage and current depending of the values of ɣ. The classical cases are recovered by taking the limit when ɣ = 1. An analysis in the frequency domain of an RC circuit shows the application and use of fractional order differential equations.

  4. How Young Children Understand Electric Circuits: Prediction, Explanation and Exploration

    Science.gov (United States)

    Glauert, Esme Bridget

    2009-01-01

    This paper reports findings from a study of young children's views about electric circuits. Twenty-eight children aged 5 and 6 years were interviewed. They were shown examples of circuits and asked to predict whether they would work and explain why. They were then invited to try out some of the circuit examples or make circuits of their own…

  5. Visual construction of characteristic equations of linear electric circuits

    Directory of Open Access Journals (Sweden)

    V.V. Kostyukov

    2013-12-01

    Full Text Available A visual identification method with application of partial circuits is developed for characteristic equation coefficients of transients in linear electric circuits. The method is based on interrelationship between the roots of algebraic polynomial and its coefficients. The method is illustrated with an example of a third-order linear electric circuit.

  6. Mobile Learning Based Worked Example in Electric Circuit (WEIEC) Application to Improve the High School Students' Electric Circuits Interpretation Ability

    Science.gov (United States)

    Yadiannur, Mitra; Supahar

    2017-01-01

    This research aims to determine the feasibility and effectivity of mobile learning based Worked Example in Electric Circuits (WEIEC) application in improving the high school students' electric circuits interpretation ability on Direct Current Circuits materials. The research method used was a combination of Four-D Models and ADDIE model. The…

  7. Aging evaluation of electrical circuits using the ECCAD system

    International Nuclear Information System (INIS)

    Edson, J.L.

    1988-01-01

    As a part of the Nuclear Regulator Commission Nuclear Plant Aging Research Program, an aging assessment of electrical circuits was conducted at the Shippingport atomic power station decommissioning project. The objective of this work was to evaluate the effectiveness of the electrical circuit characterization and diagnostic (ECCAD) system in identifying circuit conditions, to determine the present condition of selected electrical circuits, and correlate the results with aging effects. To accomplish this task, a series of electrical tests was performed on each circuit using the ECCAD system, which is composed of commercially available electronic test equipment under computer control. Test results indicate that the ECCAD system is effective in detecting and identifying aging and service wear in selected electrical circuits. The major area of degradation in the circuits tested was at the termination/connection points, whereas the cables were in generally good condition

  8. 49 CFR 236.308 - Mechanical or electric locking or electric circuits; requisites.

    Science.gov (United States)

    2010-10-01

    ..., AND APPLIANCES Interlocking Standards § 236.308 Mechanical or electric locking or electric circuits; requisites. Mechanical or electric locking or electric circuits shall be installed to prevent signals from... 49 Transportation 4 2010-10-01 2010-10-01 false Mechanical or electric locking or electric...

  9. Circuit drawings in electrical energy technology. 6. rev. ed.

    International Nuclear Information System (INIS)

    Weinert, J.

    1991-01-01

    This book contains a survey of the most important standards for graphical symbols and circuit documents for the area of electrical energy technology; it explains the circuit symbols in their construction and in their material and mental contents of terms; it contains a comparison of the circuit symbols from the DIN standards and the new DINTEC symbols taken from harmonisation, produced by arrangement in the picture column with the addition of the letters IEC; it contains a selection of circuit symbols of the IEC, USA, Canada and Great Britain; it supplements the necessary standards for producing circuit documents by extracts and references; it shows examples for the symbols of electrical equipment by using circuit symbols; it develops and explains the various kinds of representation of electrical circuits by circuit diagrams; it leads to reading and understanding the functioning of circuits by descriptions of functions; it gives examples of applications for designing and producing circuit documents, as used in practice; it contributes to arranging electrical plant according to the 'recognised rules of electrical engineering' and increasing safety by reference to the DIN-VDE regulations connected with representation, and it is a great help in designing electrical energy plant by its technical and electrical data. (orig.) [de

  10. The Elusive Memristor: Properties of Basic Electrical Circuits

    Science.gov (United States)

    Joglekar, Yogesh N.; Wolf, Stephen J.

    2009-01-01

    We present an introduction to and a tutorial on the properties of the recently discovered ideal circuit element, a memristor. By definition, a memristor M relates the charge "q" and the magnetic flux [phi] in a circuit and complements a resistor R, a capacitor C and an inductor L as an ingredient of ideal electrical circuits. The properties of…

  11. 30 CFR 75.509 - Electric power circuit and electric equipment; deenergization.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric power circuit and electric equipment... LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.509 Electric power circuit and electric equipment; deenergization. [Statutory Provisions] All...

  12. Device, system and method for a sensing electrical circuit

    Science.gov (United States)

    Vranish, John M. (Inventor)

    2009-01-01

    The invention relates to a driven ground electrical circuit. A driven ground is a current-measuring ground termination to an electrical circuit with the current measured as a vector with amplification. The driven ground module may include an electric potential source V.sub.S driving an electric current through an impedance (load Z) to a driven ground. Voltage from the source V.sub.S excites the minus terminal of an operational amplifier inside the driven ground which, in turn, may react by generating an equal and opposite voltage to drive the net potential to approximately zero (effectively ground). A driven ground may also be a means of passing information via the current passing through one grounded circuit to another electronic circuit as input. It may ground one circuit, amplify the information carried in its current and pass this information on as input to the next circuit.

  13. Secondary School Students' Misconceptions about Simple Electric Circuits

    Science.gov (United States)

    Küçüközer, Hüseyin; Kocakülah, Sabri

    2007-01-01

    The aim of this study is to reveal secondary school students' misconceptions about simple electric circuits and to define whether specific misconceptions peculiar to Turkish students exist within those identified. Data were obtained with a conceptual understanding test for simple electric circuits and semi-structured interviews. Conceptual…

  14. Beam dynamics requirements for HL–LHC electrical circuits

    CERN Document Server

    Gamba, Davide; Cerqueira Bastos, Miguel; Coello De Portugal - Martinez Vazquez, Jaime Maria; De Maria, Riccardo; Giovannozzi, Massimo; Martino, Michele; Tomas Garcia, Rogelio

    2017-01-01

    A certain number of LHC magnets and relative electrical circuits will be replaced for the HL-LHC upgrade. The performance of the new circuits will need to be compatible with the current installation, and to provide the necessary improvements to meet the tight requirements of the new operational scenario. This document summarises the present knowledge of the performance and use of the LHC circuits and, based on this and on the new optics requirements, provides the necessary specifications for the new HL-LHC electrical circuits.

  15. Pre-assembling electric circuits of braided conductors

    International Nuclear Information System (INIS)

    Mercado Gomez, Martin Elias

    1999-01-01

    The present article has for object to give to know an innovative concept of pre-assembling electric circuits for distribution of normal and regulated power, to the work position like integral subsystems of the calls intelligent buildings

  16. The elusive memristor: properties of basic electrical circuits

    International Nuclear Information System (INIS)

    Joglekar, Yogesh N; Wolf, Stephen J

    2009-01-01

    We present an introduction to and a tutorial on the properties of the recently discovered ideal circuit element, a memristor. By definition, a memristor M relates the charge q and the magnetic flux φ in a circuit and complements a resistor R, a capacitor C and an inductor L as an ingredient of ideal electrical circuits. The properties of these three elements and their circuits are a part of the standard curricula. The existence of the memristor as the fourth ideal circuit element was predicted in 1971 based on symmetry arguments, but was clearly experimentally demonstrated just last year. We present the properties of a single memristor, memristors in series and parallel, as well as ideal memristor-capacitor (MC), memristor-inductor (ML) and memristor-capacitor-inductor (MCL) circuits. We find that the memristor has hysteretic current-voltage characteristics. We show that the ideal MC (ML) circuit undergoes non-exponential charge (current) decay with two time scales and that by switching the polarity of the capacitor, an ideal MCL circuit can be tuned from overdamped to underdamped. We present simple models which show that these unusual properties are closely related to the memristor's internal dynamics. This tutorial complements the pedagogy of ideal circuit elements (R, C and L) and the properties of their circuits, and is aimed at undergraduate physics and electrical engineering students

  17. The elusive memristor: properties of basic electrical circuits

    Energy Technology Data Exchange (ETDEWEB)

    Joglekar, Yogesh N; Wolf, Stephen J [Department of Physics, Indiana University Purdue University Indianapolis, Indianapolis, IN 46202 (United States)], E-mail: yojoglek@iupui.edu

    2009-07-15

    We present an introduction to and a tutorial on the properties of the recently discovered ideal circuit element, a memristor. By definition, a memristor M relates the charge q and the magnetic flux {phi} in a circuit and complements a resistor R, a capacitor C and an inductor L as an ingredient of ideal electrical circuits. The properties of these three elements and their circuits are a part of the standard curricula. The existence of the memristor as the fourth ideal circuit element was predicted in 1971 based on symmetry arguments, but was clearly experimentally demonstrated just last year. We present the properties of a single memristor, memristors in series and parallel, as well as ideal memristor-capacitor (MC), memristor-inductor (ML) and memristor-capacitor-inductor (MCL) circuits. We find that the memristor has hysteretic current-voltage characteristics. We show that the ideal MC (ML) circuit undergoes non-exponential charge (current) decay with two time scales and that by switching the polarity of the capacitor, an ideal MCL circuit can be tuned from overdamped to underdamped. We present simple models which show that these unusual properties are closely related to the memristor's internal dynamics. This tutorial complements the pedagogy of ideal circuit elements (R, C and L) and the properties of their circuits, and is aimed at undergraduate physics and electrical engineering students.

  18. Electrical circuits in biomedical engineering problems with solutions

    CERN Document Server

    Keskin, Ali Ümit

    2017-01-01

    This authored monograph presents a comprehensive and in-depth analysis of electrical circuit theory in biomedical engineering, ideally suited as textbook for a course program. The book contains methods and theory, but the topical focus is placed on practical applications of circuit theory, including problems, solutions and case studies. The target audience primarily comprises researchers and experts in electrical engineering who intend to embark on biomedical applications. The book is also very well suited for graduate students in the field. .

  19. Energy pumping in electrical circuits under avalanche noise.

    Science.gov (United States)

    Kanazawa, Kiyoshi; Sagawa, Takahiro; Hayakawa, Hisao

    2014-07-01

    We theoretically study energy pumping processes in an electrical circuit with avalanche diodes, where non-Gaussian athermal noise plays a crucial role. We show that a positive amount of energy (work) can be extracted by an external manipulation of the circuit in a cyclic way, even when the system is spatially symmetric. We discuss the properties of the energy pumping process for both quasistatic and finite-time cases, and analytically obtain formulas for the amounts of the work and the power. Our results demonstrate the significance of the non-Gaussianity in energetics of electrical circuits.

  20. An Unsolved Electric Circuit: A Common Misconception

    Science.gov (United States)

    Harsha, N. R. Sree; Sreedevi, A.; Prakash, Anupama

    2015-01-01

    Despite a number of theories in circuit analysis, little is known about the behaviour of ideal equal voltage sources in parallel, connected across a resistive load. We neither have any theory that can predict the voltage source that provides the load current, nor is there any method to test it experimentally. In a series of experiments performed…

  1. Stochastic Resonance Induced by Dichotomous Resistor in an Electric Circuit

    International Nuclear Information System (INIS)

    Li Jinghui; Han Yinxia

    2007-01-01

    An electric circuit with dichotomous resistor is investigated. It is shown that the amplitude of the average electric current washing the resistor represents the phenomenon of stochastic resonance, which is the response as a function of the correlation time of the dichotomous resistor.

  2. Electrical circuit model of ITO/AZO/Ge photodetector.

    Science.gov (United States)

    Patel, Malkeshkumar; Kim, Joondong

    2017-10-01

    In this data article, ITO/AZO/Ge photodetector was investigated for electrical circuit model. Due to the double (ITO and AZO) transparent metal-oxide films (DOI:10.1016/j.mssp.2016.03.007) (Yun et al., 2016) [1], the Ge heterojunction device has a better interface quality due to the AZO layer with a low electrical resistance due to the ITO layer (Yun et al., 2015) [2]. The electrical and interfacial benefitted ITO/AZO/Ge heterojunction shows the quality Schottky junction. In order to investigate the device, the ITO/AZO/Ge heterojunction was analyzed by R-C circuit model using the impedance spectroscopy.

  3. Introduction to Biosensors From Electric Circuits to Immunosensors

    CERN Document Server

    Yoon, Jeong-Yeol

    2013-01-01

    Introduction to Biosensors: From Electric Circuits to Immunosensors discusses underlying circuitry of sensors for biomedical and biological engineers as well as biomedical sensing modalities for electrical engineers while providing an applications-based approach to the study of biosensors with over 13 extensive, hands-on labs. The material is presented using a building-block approach, beginning with the fundamentals of sensor design and temperature sensors and ending with more complicated biosensors. This book also: Provides electrical engineers with the specific knowledge they need to understand biological sensing modalities Provides biomedical engineers with a solid background in circuits and systems Includes complete coverage of temperature sensors, electrochemical sensors, DNA and immunosensors, piezoelectric sensors and immunosensing in a micofluidic device Introduction to Biosensors: From Electric Circuits to Immunosensors aims to provide an interdisciplinary approach to biosensors that will be apprecia...

  4. Switchless charge-discharge circuit for electrical capacitance tomography

    International Nuclear Information System (INIS)

    Kryszyn, J; Smolik, W T; Radzik, B; Olszewski, T; Szabatin, R

    2014-01-01

    The main factor limiting the performance of electrical capacitance tomography (ECT) is an extremely low value of inter-electrode capacitances. The charge-discharge circuit is a well suited circuit for a small capacitance measurement due to its immunity to noise and stray capacitance, although it has a problem associated with a charge injected by the analogue switches, which results in a dc offset. This paper presents a new diode-based circuit for capacitance measurement in which a charge transfer method is realized without switches. The circuit was built and tested in one channel configuration with 16 multiplexed electrodes. The performance of the elaborated circuit and a comparison with a classic charge-discharge circuit are presented. The elaborated circuit can be used for sensors with inter-electrode capacitances not lower than 10 fF. The presented approach allows us to obtain a similar performance to the classic charge-discharge circuit, but has a simplified design. A lack of the need to synchronize the analogue switches in the transmitter and the receiver part of this circuit could be a desirable feature in the design of measurement systems integrated with electrodes. (paper)

  5. High-speed Integrated Circuits for electrical/Optical Interfaces

    DEFF Research Database (Denmark)

    Jespersen, Christoffer Felix

    2008-01-01

    This thesis is a continuation of the effort to increase the bandwidth of communicationnetworks. The thesis presents the results of the design of several high-speed electrical ircuits for an electrical/optical interface. These circuits have been a contribution to the ESTA project in collaboration...... circuits at the receiver interface, though VCOs are also found in the transmitter where a multitude of independent sources have to be mutually synchronized before multiplexing. The circuits are based on an InP DHBT process (VIP-2) supplied by Vitesse and made publicly available as MPW. The VIP-2 process...... represents the avant-garde of InP technology, with ft and fmax well above 300 GHz. Principles of high speed design are presented and described as a useful background before proceeding to circuits. A static divider is used as an example to illustrate many of the design principles. Theory and fundamentals...

  6. [Electric short-circuit incident observed with "Upsher" laryngoscopes].

    Science.gov (United States)

    Tritsch, L; Vailly, B

    2006-01-01

    We observed an electrical short-circuit between a fasten screw of the printed circuit and the handle of an Upsher universal laryngoscope (serial number UQ1). The isolating Silicone layer was broken above the screw. This isolation defect was found all over our Upsher laryngoscopes of the UQ1 series. No doubt that if accumulators were used instead of batteries, emitted heat would be in largest amount and perhaps dangerous.

  7. Power amplifier circuits for functional electrical stimulation systems

    Directory of Open Access Journals (Sweden)

    Delmar Carvalho de Souza

    Full Text Available Abstract Introduction: Functional electrical stimulation (FES is a technique that has been successfully employed in rehabilitation treatment to mitigate problems after spinal cord injury (SCI. One of the most relevant modules in a typical FES system is the power or output amplifier stage, which is responsible for the application of voltage or current pulses of proper intensity to the biological tissue, applied noninvasively via electrodes, placed on the skin surface or inside the muscular tissue, closer to the nervous fibers. The goals of this paper are to describe and discuss about the main power output designs usually employed in transcutaneous functional electrical stimulators as well as safety precautions taken to protect patients. Methods A systematic review investigated the circuits of papers published in IEEE Xplore and ScienceDirect databases from 2000 to 2016. The query terms were “((FES or Functional electric stimulator and (circuit or design” with 274 papers retrieved from IEEE Xplore and 29 from ScienceDirect. After the application of exclusion criteria the amount of papers decreased to 9 and 2 from IEEE Xplore and ScienceDirect, respectively. One paper was inserted in the results as a technological contribution to the field. Therefore, 12 papers presented power stage circuits suitable to stimulate great muscles. Discussion The retrieved results presented relevant circuits with different electronic strategies and circuit components. Some of them considered patient safety strategies or aimed to preserve muscle homeostasis such as biphasic current application, which prevents charge accumulation in stimulated tissues as well as circuits that dealt with electrical impedance variation to keep the electrode-tissue interface within an electrochemical safe regime. The investigation revealed a predominance of design strategies using operational amplifiers in power circuits, current outputs, and safety methods to reduce risks of electrical

  8. 30 CFR 77.506-1 - Electric equipment and circuits; overload and short circuit protection; minimum requirements.

    Science.gov (United States)

    2010-07-01

    ... short circuit protection; minimum requirements. 77.506-1 Section 77.506-1 Mineral Resources MINE SAFETY...-1 Electric equipment and circuits; overload and short circuit protection; minimum requirements. Devices providing either short circuit protection or protection against overload shall conform to the...

  9. 30 CFR 75.518-1 - Electric equipment and circuits; overload and short circuit protection; minimum requirements.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric equipment and circuits; overload and short circuit protection; minimum requirements. 75.518-1 Section 75.518-1 Mineral Resources MINE SAFETY... short circuit protection; minimum requirements. A device to provide either short circuit protection or...

  10. Hydraulic actuator for an electric circuit breaker

    Science.gov (United States)

    Imam, Imdad [Colonie, NY

    1983-01-01

    This actuator comprises a fluid motor having a piston, a breaker-opening space at one side of the piston, and a breaker-closing space at its opposite side. An accumulator freely communicates with the breaker-opening space for supplying pressurized fluid thereto during a circuit breaker opening operation. The breaker-opening space and the breaker-closing space are connected by an impeded flow passage. A pilot valve opens to allow the pressurized liquid in the breaker-closing space to flow to a back chamber of a normally closed main valve to cause the main valve to be opened during a circuit breaker opening operation to release the pressurized liquid from the breaker-closing space. An impeded passage affords communication between the back chamber and a sump located on the opposite side of the main valve from the back chamber. The pilot valve and impeded passage allow rapid opening of the main valve with pressurized liquid from the breaker closing side of the piston.

  11. 30 CFR 77.501 - Electric distribution circuits and equipment; repair.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric distribution circuits and equipment... OF UNDERGROUND COAL MINES Electrical Equipment-General § 77.501 Electric distribution circuits and equipment; repair. No electrical work shall be performed on electric distribution circuits or equipment...

  12. Electrical circuits of an electromagnetic isotope separator

    International Nuclear Information System (INIS)

    Neyron, A.

    1959-01-01

    After an outline of the general principles governing the operation of an electromagnetic isotope separator, the electrical characteristics necessary to this operation are given. First the electrical characteristics of the ion source are briefly presented. The author then gives a detailed account of the construction of the H.T. acceleration supply of which the maxima characteristics are 80 kV and 150 mA with stabilisation of the order of 4.10 -4 . Reprint of a paper published in 'Industries Atomiques' - n. 3-4, 1959

  13. Electrical overstress (EOS) devices, circuits and systems

    CERN Document Server

    Voldman, Steven H

    2013-01-01

    Electrical Overstress (EOS) continues to impact semiconductor manufacturing, semiconductor components and systems as technologies scale from micro- to nano-electronics.  This bookteaches the fundamentals of electrical overstress  and how to minimize and mitigate EOS failures. The text provides a clear picture of EOS phenomena, EOS origins, EOS sources, EOS physics, EOS failure mechanisms, and EOS on-chip and system design.  It provides an illuminating insight into the sources of EOS in manufacturing, integration of on-chip, and system level EOS protection networks, followed by examples in spe

  14. Students conception and perception of simple electrical circuit

    Science.gov (United States)

    Setyani, ND; Suparmi; Sarwanto; Handhika, J.

    2017-11-01

    This research aims to describe the profile of the students’ conception and perception on the simple electrical circuit. The results of this research suppose to be used as a reference by teachers to use learning models or strategies to improve understanding the physics concept. The research method used is descriptive qualitative. Research subjects are the students of physics education program, Universitas Sebelas Maret, Surakarta, Indonesia (49 students). The results showed that students have alternative conceptions. Their conceptions are (1) a high-voltage wire has an electric current and can cause electric shock, (2) the potential difference and the value of resistance used in a circuit is influenced by electric current, (3) the value of resistance of a lamp is proportional to the filament thickness, (4) the amount of electric current that coming out from the positive pole battery is the same for all type of circuit, in series or parallel (battery is constant current sources), (5) the current at any resistor in the series circuit is influenced by the resistor used, (6) the resistor consume the current through it. This incorrect conception can cause misconceptions.

  15. Electric power globalization and reforming

    International Nuclear Information System (INIS)

    Soares Neto, Jose Lino

    1999-01-01

    The central issue of debate was the need to align the energy sector's options and organization with changing global patterns of economic and social development, characterized by the increasing role played by the private sector, greater integration in the world economy, and new economic and social priorities such as efficiency, decentralization, deregulation, and a closer attention to environmental issues. The aim of the work was to define the economic and political forces of the electric power sector regulation restructuring

  16. Electrical short circuit and current overload tests on aircraft wiring

    Science.gov (United States)

    Cahill, Patricia

    1995-01-01

    The findings of electrical short circuit and current overload tests performed on commercial aircraft wiring are presented. A series of bench-scale tests were conducted to evaluate circuit breaker response to overcurrent and to determine if the wire showed any visible signs of thermal degradation due to overcurrent. Three types of wire used in commercial aircraft were evaluated: MIL-W-22759/34 (150 C rated), MIL-W-81381/12 (200 C rated), and BMS 1360 (260 C rated). A second series of tests evaluated circuit breaker response to short circuits and ticking faults. These tests were also meant to determine if the three test wires behaved differently under these conditions and if a short circuit or ticking fault could start a fire. It is concluded that circuit breakers provided reliable overcurrent protection. Circuit breakers may not protect wire from ticking faults but can protect wire from direct shorts. These tests indicated that the appearance of a wire subjected to a current that totally degrades the insulation looks identical to a wire subjected to a fire; however the 'fire exposed' conductor was more brittle than the conductor degraded by overcurrent. Preliminary testing indicates that direct short circuits are not likely to start a fire. Preliminary testing indicated that direct short circuits do not erode insulation and conductor to the extent that ticking faults did. Circuit breakers may not safeguard against the ignition of flammable materials by ticking faults. The flammability of materials near ticking faults is far more important than the rating of the wire insulation material.

  17. Integrated electric circuit CAD system in Minolta Camera Co. Ltd

    Energy Technology Data Exchange (ETDEWEB)

    Nakagami, Tsuyoshi; Hirata, Sumiaki; Matsumura, Fumihiko

    1988-08-26

    Development background, fundamental concept, details and future plan of the integrated electric circuit CAD system for OA equipment are presented. The central integrated database is basically intended to store experiences or know-hows, to cover the wide range of data required for designs, and to provide a friendly interface. This easy-to-use integrated database covers the drawing data, parts information, design standards, know-hows and system data. The system contains the circuit design function to support drawing circuit diagrams, the wiring design function to support the wiring and arrangement of printed circuit boards and various parts integratedly, and the function to verify designs, to make full use of parts or technical information, to maintain the system security. In the future, as the system will be wholly in operation, the design period reduction, quality improvement and cost saving will be attained by this integrated design system. (19 figs, 2 tabs)

  18. On the Possibility of the Jerk Derivative in Electrical Circuits

    Directory of Open Access Journals (Sweden)

    J. F. Gómez-Aguilar

    2016-01-01

    Full Text Available A subclass of dynamical systems with a time rate of change of acceleration are called Newtonian jerky dynamics. Some mechanical and acoustic systems can be interpreted as jerky dynamics. In this paper we show that the jerk dynamics are naturally obtained for electrical circuits using the fractional calculus approach with order γ. We consider fractional LC and RL electrical circuits with 1⩽γ<2 for different source terms. The LC circuit has a frequency ω dependent on the order of the fractional differential equation γ, since it is defined as ω(γ=ω0γγ1-γ, where ω0 is the fundamental frequency. For γ=3/2, the system is described by a third-order differential equation with frequency ω~ω03/2, and assuming γ=2 the dynamics are described by a fourth differential equation for jerk dynamics with frequency ω~ω02.

  19. Regulated Electric Drainage and its Interference with Track Circuits

    Directory of Open Access Journals (Sweden)

    Vaclav Kolar

    2018-01-01

    Full Text Available Electric drainage is a power electronic device used to protect underground metal devices (such as piping from the corrosive effects of stray currents. Stray currents are usually caused by DC electric traction, such as trams or railways. In places where stray currents leave the underground device and return into rails, they cause significant electrochemical corrosion of buried devices. The principle of electric drainage is based on electrical connection between the underground device and electric traction rails, which ensures that current flows through this connection, instead of flowing into the ground. Nowadays, the most widely used type is regulated electric drainage, where current is regulated by means of Pulse Width Modulation (PWM. Because of this modulation, current flowing through the drainage contains harmonic components with different frequencies. In modern railways, track circuits are often used as an important part of the track security system. For safe operation, it is necessary to ensure that frequencies generated by the drainage do not interfere with track circuits. This paper describes the design of a regulated drainage control system, with regard to its compatibility with track circuits and this paper contains related computer simulations and discussion of the results

  20. Calibration of capacitance probe sensors using Electric Circuit Theory

    NARCIS (Netherlands)

    Kelleners, T.J.; Soppe, R.W.O.; Robinson, D.A.; Schaap, M.G.; Ayars, J.E.; Skaggs, T.H.

    2004-01-01

    Capacitance probe sensors are an attractive electromagnetic technique for estimating soil water content. There is concern, however, about the influence of soil salinity and soil temperature on the sensors. We present an electric circuit model that relates the sensor frequency to the permittivity of

  1. Web-Based Trainer for Electrical Circuit Analysis

    Science.gov (United States)

    Weyten, L.; Rombouts, P.; De Maeyer, J.

    2009-01-01

    A Web-based system for training electric circuit analysis is presented in this paper. It is centered on symbolic analysis techniques and it not only verifies the student's final answer, but it also tracks and coaches him/her through all steps of his/her reasoning path. The system mimics homework assignments, enhanced by immediate personalized…

  2. Turkish Students' Conceptions about the Simple Electric Circuits

    Science.gov (United States)

    Cepni, Salih; Keles, Esra

    2006-01-01

    In this study, the Turkish students' understanding level of electric circuits consisting of two bulbs and one battery was investigated by using open-ended questions. Two-hundred fifty students, whose ages range from 11 to 22, were chosen from five different groups at primary, secondary and university levels in Trabzon in Turkey. In analyzing…

  3. 30 CFR 56.4011 - Abandoned electric circuits.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Abandoned electric circuits. 56.4011 Section 56.4011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Fire Prevention and...

  4. A Computer Program for Short Circuit Analysis of Electric Power ...

    African Journals Online (AJOL)

    The Short Circuit Analysis Program (SCAP) is to be used to assess the composite effects of unbalanced and balanced faults on the overall reliability of electric power system. The program uses the symmetrical components method to compute all phase and sequence quantities for any bus or branch of a given power network ...

  5. Structure preserving port-Hamiltonian model reduction of electrical circuits

    NARCIS (Netherlands)

    Polyuga, R.; Schaft, van der A.J.; Benner, P.; Hinze, M.; Maten, ter E.J.W.

    2011-01-01

    This paper discusses model reduction of electrical circuits based on a port-Hamiltonian representation. It is shown that by the use of the Kalman decomposition an uncontrollable and/or unobservable port-Hamiltonian system is reduced to a controllable/observable system that inherits the

  6. Student generated assignments about electrical circuits in a computer simulation

    NARCIS (Netherlands)

    Vreman-de Olde, Cornelise; de Jong, Anthonius J.M.

    2004-01-01

    In this study we investigated the design of assignments by students as a knowledge-generating activity. Students were required to design assignments for 'other students' in a computer simulation environment about electrical circuits. Assignments consisted of a question, alternatives, and feedback on

  7. Electrical circuit model of ITO/AZO/Ge photodetector

    Directory of Open Access Journals (Sweden)

    Malkeshkumar Patel

    2017-10-01

    Full Text Available In this data article, ITO/AZO/Ge photodetector was investigated for electrical circuit model. Due to the double (ITO and AZO transparent metal-oxide films (DOI:10.1016/j.mssp.2016.03.007 (Yun et al., 2016 [1], the Ge heterojunction device has a better interface quality due to the AZO layer with a low electrical resistance due to the ITO layer (Yun et al., 2015 [2]. The electrical and interfacial benefitted ITO/AZO/Ge heterojunction shows the quality Schottky junction. In order to investigate the device, the ITO/AZO/Ge heterojunction was analyzed by R–C circuit model using the impedance spectroscopy.

  8. Chaotic behaviour of a fourth-order autonomous electric circuit

    International Nuclear Information System (INIS)

    Koliopanos, Ch.L.; Kyprianidis, I.M.; Stouboulos, I.N.; Anagnostopoulos, A.N.; Magafas, L.

    2003-01-01

    The chaotic dynamics of a fourth-order autonomous nonlinear electric circuit was studied by measuring its response in the form of chaotic time series. The circuit consists of two active elements, one linear negative conductance and one nonlinear resistor exhibiting a symmetrical piecewise-linear v-i characteristic and two capacitances C 1 and C 2 , which serve as the control parameters of the system. From the experimental time series the minimum embedding dimensions m min =4, correlation dimensions ν, with positive noninteger values, and Kolmogorov entropies, tending to constant positive values, were determined by numerical evaluation for the examined states of the system

  9. Using graph theory for automated electric circuit solving

    International Nuclear Information System (INIS)

    Toscano, L; Stella, S; Milotti, E

    2015-01-01

    Graph theory plays many important roles in modern physics and in many different contexts, spanning diverse topics such as the description of scale-free networks and the structure of the universe as a complex directed graph in causal set theory. Graph theory is also ideally suited to describe many concepts in computer science. Therefore it is increasingly important for physics students to master the basic concepts of graph theory. Here we describe a student project where we develop a computational approach to electric circuit solving which is based on graph theoretic concepts. This highly multidisciplinary approach combines abstract mathematics, linear algebra, the physics of circuits, and computer programming to reach the ambitious goal of implementing automated circuit solving. (paper)

  10. Printed Graphene Derivative Circuits as Passive Electrical Filters.

    Science.gov (United States)

    Sinar, Dogan; Knopf, George K

    2018-02-23

    The objective of this study is to inkjet print resistor-capacitor ( RC ) low pass electrical filters, using a novel water-based cellulose graphene ink, and compare the voltage-frequency and transient behavior to equivalent circuits constructed from discrete passive components. The synthesized non-toxic graphene-carboxymethyl cellulose (G-CMC) ink is deposited on mechanically flexible polyimide substrates using a customized printer that dispenses functionalized aqueous solutions. The design of the printed first-order and second-order low-pass RC filters incorporate resistive traces and interdigitated capacitors. Low pass filter characteristics, such as time constant, cut-off frequency and roll-off rate, are determined for comparative analysis. Experiments demonstrate that for low frequency applications (graphene derivative circuits performed as well as the circuits constructed from discrete resistors and capacitors for both low pass filter and RC integrator applications. The impact of mechanical stress due to bending on the electrical performance of the flexible printed circuits is also investigated.

  11. Printed Graphene Derivative Circuits as Passive Electrical Filters

    Directory of Open Access Journals (Sweden)

    Dogan Sinar

    2018-02-01

    Full Text Available The objective of this study is to inkjet print resistor-capacitor (RC low pass electrical filters, using a novel water-based cellulose graphene ink, and compare the voltage-frequency and transient behavior to equivalent circuits constructed from discrete passive components. The synthesized non-toxic graphene-carboxymethyl cellulose (G-CMC ink is deposited on mechanically flexible polyimide substrates using a customized printer that dispenses functionalized aqueous solutions. The design of the printed first-order and second-order low-pass RC filters incorporate resistive traces and interdigitated capacitors. Low pass filter characteristics, such as time constant, cut-off frequency and roll-off rate, are determined for comparative analysis. Experiments demonstrate that for low frequency applications (<100 kHz the printed graphene derivative circuits performed as well as the circuits constructed from discrete resistors and capacitors for both low pass filter and RC integrator applications. The impact of mechanical stress due to bending on the electrical performance of the flexible printed circuits is also investigated.

  12. Mathematical Modelling and Simulation of Electrical Circuits and Semiconductor Devices

    CERN Document Server

    Merten, K; Bulirsch, R

    1990-01-01

    Numerical simulation and modelling of electric circuits and semiconductor devices are of primal interest in today's high technology industries. At the Oberwolfach Conference more than forty scientists from around the world, in­ cluding applied mathematicians and electrical engineers from industry and universities, presented new results in this area of growing importance. The contributions to this conference are presented in these proceedings. They include contributions on special topics of current interest in circuit and device simulation, as well as contributions that present an overview of the field. In the semiconductor area special lectures were given on mixed finite element methods and iterative procedures for the solution of large linear systems. For three dimensional models new discretization procedures including software packages were presented. Con­ nections between semiconductor equations and the Boltzmann equation were shown as well as relations to the quantum transport equation. Other issues dis...

  13. 49 CFR 236.16 - Electric lock, main track releasing circuit.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Electric lock, main track releasing circuit. 236... Rules and Instructions: All Systems General § 236.16 Electric lock, main track releasing circuit. When an electric lock releasing circuit is provided on the main track to permit a train or an engine to...

  14. Azerbaijan Technical University’s Experience in Teaching Linear Electrical Circuit Theory

    Directory of Open Access Journals (Sweden)

    G. A. Mamedov

    2006-01-01

    Full Text Available An experience in teaching linear electrical circuit theory at the Azerbaijan Technical University is presented in the paper. The paper describes structure of the Linear Electrical Circuit Theory course worked out by the authors that contains a section on electrical calculation of track circuits, information on electro-magnetic compatibility and typical tests for better understanding of the studied subject.

  15. Basic Guidelines to Introduce Electric Circuit Simulation Software in a General Physics Course

    Science.gov (United States)

    Moya, A. A.

    2018-01-01

    The introduction of electric circuit simulation software for undergraduate students in a general physics course is proposed in order to contribute to the constructive learning of electric circuit theory. This work focuses on the lab exercises based on dc, transient and ac analysis in electric circuits found in introductory physics courses, and…

  16. Electrical circuit modeling of conductors with skin effect

    International Nuclear Information System (INIS)

    Kerst, D.W.; Sprott, J.C.

    1986-01-01

    The electrical impedance of a lossy conductor is a complicated function of time (or frequency) because of the skin effect. By solving the diffusion equation for magnetic fields in conductors of several prototypical shapes, the impedance can be calculated as a function of time for a step function of current. The solution suggests an electrical circuit representation that allows calculation of time-dependent voltages and currents of arbitrary waveforms. A technique using an operational amplifier to determine the current in such a conductor by measuring some external voltage is described. Useful analytical approximations to the results are derived

  17. Electrical circuit modeling and analysis of microwave acoustic interaction with biological tissues.

    Science.gov (United States)

    Gao, Fei; Zheng, Qian; Zheng, Yuanjin

    2014-05-01

    Numerical study of microwave imaging and microwave-induced thermoacoustic imaging utilizes finite difference time domain (FDTD) analysis for simulation of microwave and acoustic interaction with biological tissues, which is time consuming due to complex grid-segmentation and numerous calculations, not straightforward due to no analytical solution and physical explanation, and incompatible with hardware development requiring circuit simulator such as SPICE. In this paper, instead of conventional FDTD numerical simulation, an equivalent electrical circuit model is proposed to model the microwave acoustic interaction with biological tissues for fast simulation and quantitative analysis in both one and two dimensions (2D). The equivalent circuit of ideal point-like tissue for microwave-acoustic interaction is proposed including transmission line, voltage-controlled current source, envelop detector, and resistor-inductor-capacitor (RLC) network, to model the microwave scattering, thermal expansion, and acoustic generation. Based on which, two-port network of the point-like tissue is built and characterized using pseudo S-parameters and transducer gain. Two dimensional circuit network including acoustic scatterer and acoustic channel is also constructed to model the 2D spatial information and acoustic scattering effect in heterogeneous medium. Both FDTD simulation, circuit simulation, and experimental measurement are performed to compare the results in terms of time domain, frequency domain, and pseudo S-parameters characterization. 2D circuit network simulation is also performed under different scenarios including different sizes of tumors and the effect of acoustic scatterer. The proposed circuit model of microwave acoustic interaction with biological tissue could give good agreement with FDTD simulated and experimental measured results. The pseudo S-parameters and characteristic gain could globally evaluate the performance of tumor detection. The 2D circuit network

  18. Tin Whisker Electrical Short Circuit Characteristics. Part 2

    Science.gov (United States)

    Courey, Karim J.; Asfour, Shihab S.; Onar, Arzu; Bayliss, Jon A.; Ludwig, Lawrence L.; Wright, Maria C.

    2009-01-01

    Existing risk simulations make the assumption that when a free tin whisker has bridged two adjacent exposed electrical conductors, the result is an electrical short circuit. This conservative assumption is made because shorting is a random event that has an unknown probability associated with it. Note however that due to contact resistance electrical shorts may not occur at lower voltage levels. In our first article we developed an empirical probability model for tin whisker shorting. In this paper, we develop a more comprehensive empirical model using a refined experiment with a larger sample size, in which we studied the effect of varying voltage on the breakdown of the contact resistance which leads to a short circuit. From the resulting data we estimated the probability distribution of an electrical short, as a function of voltage. In addition, the unexpected polycrystalline structure seen in the focused ion beam (FIB) cross section in the first experiment was confirmed in this experiment using transmission electron microscopy (TEM). The FIB was also used to cross section two card guides to facilitate the measurement of the grain size of each card guide's tin plating to determine its finish.

  19. Java Based Symbolic Circuit Solver For Electrical Engineering Curriculum

    Directory of Open Access Journals (Sweden)

    Ruba Akram Amarin

    2012-11-01

    Full Text Available The interactive technical electronic book, TechEBook, currently under development at the University of Central Florida (UCF, introduces a paradigm shift by replacing the traditional electrical engineering course with topic-driven modules that provide a useful tool for engineers and scientists. The TechEBook comprises the two worlds of classical circuit books and interactive operating platforms such as iPads, laptops and desktops. The TechEBook provides an interactive applets screen that holds many modules, each of which has a specific application in the self learning process. This paper describes one of the interactive techniques in the TechEBook known as Symbolic Circuit Solver (SymCirc. The SymCirc develops a versatile symbolic based linear circuit with a switches solver. The solver works by accepting a Netlist and the element that the user wants to find the voltage across or current on, as input parameters. Then it either produces the plot or the time domain expression of the output. Frequency domain plots or Symbolic Transfer Functions are also produced. The solver gets its input from a Web-based GUI circuit drawer developed at UCF. Typical simulation tools that electrical engineers encounter are numerical in nature, that is, when presented with an input circuit they iteratively solve the circuit across a set of small time steps. The result is represented as a data set of output versus time, which can be plotted for further inspection. Such results do not help users understand the ultimate nature of circuits as Linear Time Invariant systems with a finite dimensional basis in the solution space. SymCirc provides all simulation results as time domain expressions composed of the basic functions that exclusively include exponentials, sines, cosines and/or t raised to any power. This paper explains the motivation behind SymCirc, the Graphical User Interface front end and how the solver actually works. The paper also presents some examples and

  20. ELECTRICAL EQUIVALENT CIRCUIT OF BIOLOGICAL OBJECTS OF VEGETABLE

    Directory of Open Access Journals (Sweden)

    I. M. Golev

    2014-01-01

    Full Text Available Summary.The results of measurements of complex biological tissues electrical resistance of vegetable origin are presented. The measurements were performed at T=296 K in the frequency range from 5 to 500 kHz. As the electrodes were covered with tin (purity of 99.9% copper plates.. Experimentally investigated the following objects: samples parenchymal tissue of Apple in the form of cylinders with a diameter of 20 mm and a length of 20 mm; Apple juice, obtained by mechanical destruction of cells; pressed Apple pulp (juice content of not more than 20%obtained by the centrifugal separation, which destroyed the system of cells. For plant tissue with a holistic system of cells in the field 103 - 105 Hz is observed pronounced minimum angle of phase shift. In the absence of cells and its value is greatly reduced .The equivalent electrical circuit fabrics are considered. The calculation of all its elements is made. The equivalent capacitance of the electrical double layer at the interface of metal measuring electrode and extracellular fluid is element of C1 . The electrical resistance of this layer alternating current is characterized by the element R1 . Chain parallel connected resistance and capacitance describes the system of plant cells. The capacitance C2 is due to the electrical capacity of the cell membranes, and the resistance R2 is the electrical resistance of the membranes and intracellular space.The coincidence of experimental and calculated data in a frequency range of more than 103 Hz satisfactory. In the region of lower frequencies is observed differences. This may be due to the specific behavior of the electrical double layer. However, in the frequency region where the electrical properties of the cell structure of the investigated tissue match good, which proves the validity of the considered equivalent circuit. It is shown that the value of the complex electrical impedance of vegetable tissue in the frequency range from 103 Hz to 105

  1. On the electrical equivalent circuits of gravitational-wave antennas

    International Nuclear Information System (INIS)

    Pallottino, G.V.; Pizzella, G.; Rome Univ.

    1978-01-01

    The electrical equivalent circuit of a Weber gravitational-wave antenna with piezoelectric transducers is derived for the various longitudinal normal modes by using the Lagrangian formalism. The analysis is applied to the antenna without piezoelectric ceramics, as well as with one or more ceramics operated in both passive and active mode. Particular attention is given to the dissipation problem in order to obtain an expression of the overall merit factor directly related to the physics of the actual dissipation processes. As an example the results are applied to a cylindrical bar with two ceramics: one for calibrating the antenna, the other as sensor of the motion. The values of the physical parameters and of the pertinent parameters of the equivalent circuit for the small antenna (20 kg) and those (predicted) for the intermediate antenna (390 kg) of the Rome group are given in the appendix. (author)

  2. Global Current Circuit Structure in a Resistive Pulsar Magnetosphere Model

    Science.gov (United States)

    Kato, Yugo. E.

    2017-12-01

    Pulsar magnetospheres have strong magnetic fields and large amounts of plasma. The structures of these magnetospheres are studied using force-free electrodynamics. To understand pulsar magnetospheres, discussions must include their outer region. However, force-free electrodynamics is limited in it does not handle dissipation. Therefore, a resistive pulsar magnetic field model is needed. To break the ideal magnetohydrodynamic (MHD) condition E\\cdot B=0, Ohm’s law is used. This work introduces resistivity depending upon the distance from the star and obtain a self-consistent steady state by time integration. Poloidal current circuits form in the magnetosphere while the toroidal magnetic field region expands beyond the light cylinder and the Poynting flux radiation appears. High electric resistivity causes a large space scale poloidal current circuit and the magnetosphere radiates a larger Poynting flux than the linear increase outside of the light cylinder radius. The formed poloidal-current circuit has width, which grows with the electric conductivity. This result contributes to a more concrete dissipative pulsar magnetosphere model.

  3. Equivalent Electrical Circuits of Thermoelectric Generators under Different Operating Conditions

    Directory of Open Access Journals (Sweden)

    Saima Siouane

    2017-03-01

    Full Text Available Energy harvesting has become a promising and alternative solution to conventional energy generation patterns to overcome the problem of supplying autonomous electrical systems. More particularly, thermal energy harvesting technologies have drawn a major interest in both research and industry. Thermoelectric Generators (TEGs can be used in two different operating conditions, under constant temperature gradient or constant heat flow. The commonly used TEG electrical model, based on a voltage source in series with an electrical resistance, shows its limitations especially under constant heat flow conditions. Here, the analytical electrical modeling, taking into consideration the internal and contact thermal resistances of a TEG under constant temperature gradient and constant heat flow conditions, is first given. To give further insight into the electrical behavior of a TEG module in different operating conditions, we propose a new and original way of emulating the above analytical expressions with usual electronics components (voltage source, resistors, diode, whose values are determined with the TEG’s parameters. Note that such a TEG emulation is particularly suited when designing the electronic circuitry commonly associated to the TEG, to realize both Maximum Power Point Tracking and output voltage regulation. First, the proposed equivalent electrical circuits are validated through simulation with a SPICE environment in static operating conditions using only one value of either temperature gradient or heat flow. Then, they are also analyzed in dynamic operating conditions where both temperature gradient and heat flow are considered as time-varying functions.

  4. An electrical circuit model for simulation of indoor radon concentration.

    Science.gov (United States)

    Musavi Nasab, S M; Negarestani, A

    2013-01-01

    In this study, a new model based on electric circuit theory was introduced to simulate the behaviour of indoor radon concentration. In this model, a voltage source simulates radon generation in walls, conductivity simulates migration through walls and voltage across a capacitor simulates radon concentration in a room. This simulation considers migration of radon through walls by diffusion mechanism in one-dimensional geometry. Data reported in a typical Greek house were employed to examine the application of this technique of simulation to the behaviour of radon.

  5. ECAP-370/IFIN - A program for the analysis of electrical and electronic circuits

    International Nuclear Information System (INIS)

    Marinescu, C.D.

    1978-05-01

    A program to be used as a tool for electrical and electronic circuit design is presented. The program performs the DC, AC, and transient analysis for circuits with a given topological structure. (author)

  6. Effects of energetic particle precipitation on the atmospheric electric circuit

    International Nuclear Information System (INIS)

    Reagan, J.B.; Meyerott, R.E.; Evans, J.E.; Imhof, W.L.; Joiner, R.G.

    1983-01-01

    The solar particle event (SPE) of August 1972 is one of the largest that has occurred in the last 20 years. Since it is so well documented, it can serve as a good example of a major perturbation to the atmospheric electric system. In this paper, ion production rates and conductivities from the ground to 80 km at the peak intensity of the event on August 4 and for 30, 35, and 40 km for the 6-day duration of the event are presented. At the peak of the event, the proton and electron precipitation currents, the ohmic current, and the vertical electric field are calculated inside the polar cap. The particle precipitation currents at this time greatly exceed the normal air earth current at altitudes above 30 km and produce reversals in the vertical electric field at 28 km and above. Calculations are presented of the vertical electric field at altitudes near 30 km where balloon measurements were made. Good agreement between the calculated and the measured vertical electric field verifies our ability to calculate disturbed conductivities at these altitudes from satellite measurements of proton spectra incident on the atmosphere. Despite the fact that at the peak of the event the vertical electric field near 30 km was shorted out by the solar particles and that the current carried by the solar particles exceeded the fair weather air-earth current density in the stratosphere by large factors, it is concluded that the largest effect of an SPE of this magnitude on the atmospheric electric circuit is due to the Forbush decrease in the galactic cosmic ray flux rather than to the large increase in solar proton flux

  7. Adaptive Electronic Quizzing Method for Introductory Electrical Circuit Course

    Directory of Open Access Journals (Sweden)

    Issa Batarseh

    2009-08-01

    Full Text Available The interactive technical electronic book, TechEBook, currently under development at the University of Central Florida, provides a useful tool for engineers and scientists through unique features compared to the most used traditional electrical circuit textbooks available in the market. TechEBook has comprised the two worlds of classical circuit books and an interactive operating platform such as laptops and desktops utilizing Java Virtual Machine operator. The TechEBook provides an interactive applets screen that holds many modules, in which each had a specific application in the self learning process. This paper describes one of the interactive techniques in the TechEBook known as, QuizMe, for evaluating the readers’ performance and the overall understanding for all subjects at any stage. The QuizMe will be displayed after each section in the TechEBook for the user to evaluate his/her understanding, which introduces the term me-learning, as a comprehensive full experience for self or individualized education. In this paper, a practical example of applying the QuizMe feature is discussed as part of a basic electrical engineering course currently given at the University of Central Florida.

  8. 30 CFR 18.51 - Electrical protection of circuits and equipment.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electrical protection of circuits and equipment... TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.51 Electrical protection of circuits and equipment. (a) An automatic...

  9. Electrical equivalent circuit of an ion-exchange membrane system

    Energy Technology Data Exchange (ETDEWEB)

    Nikonenko, Victor V., E-mail: v_nikonenko@mail.r [Membrane Institute, Kuban State University, Krasnodar (Russian Federation); Kozmai, Anton E. [Membrane Institute, Kuban State University, Krasnodar (Russian Federation)

    2011-01-01

    Usually, the current flowing through an electrochemical cell is divided into the faradaic current going to an electrochemical interface reaction, and the current charging electric double layer (EDL). This division leads to the Randles-Ershler equivalent circuit with an EDL capacitance in one branch, and the faradaic impedance in the other, specific for each particular system. However, the physics of the separation of the impedance into faradaic and capacitive components for different electrochemical systems is not sufficiently clear. The most of derivations resulting in the formal construction of the Randles-Ershler or similar equivalent circuits are based on the a priori separation of the electroneutral and the double-layer regions. In this paper, we derive an equation for the impedance of a three-layer system consisted of an ion-exchange membrane and two adjoining diffusion boundary layers (DBL) starting from the Poisson equation. The system is polarized by a constant electric current over which a small sinusoidal signal is applied. The equation shows that the impedance of the considered system can be formally interpreted via an equivalent circuit with a frequency dependent capacitance in one branch and a finite-length Warburg-type impedance in the other. To take into account this dependence, the impedance of the system may be presented as a series connection of five circuits. Three of them are consisted of a geometric capacitance connected in parallel with an ohmic resistance, respectively, for both diffusion layers and for the membrane bulk; the two others being the double-layer capacitance in parallel with the finite-length Warburg impedance for the left and the right interfaces, respectively. The comparison of the impedance spectra calculated within our analytical approach with those obtained by the full numerical solution of the Nernst-Planck-Poisson (NPP) equations shows a good agreement. Different possible situations, which might arise in real systems

  10. Improvement of diagnostic techniques and electrical circuit in azo dye degradation by high voltage electrical discharge

    International Nuclear Information System (INIS)

    Shen Yongjun; Lei Lecheng; Zhang Xingwang; Zhou Minghua; Zhang Yi

    2008-01-01

    Fast electrical diagnostics and improvement of electrical circuits for methyl orange (MO) degradation by high voltage pulsed electrical discharge were investigated. To eliminate electromagnetic radiation, several effective methods were employed. RG 218 coaxial cable was substituted for the common transmission lines to transmit high voltage pulses, and multi-lines in parallel were earthed to avoid electromagnetic interference and, additionally, to reduce the stray inductance of the electrical circuit and increase the pulse rise rate to reduce the energy losses in the transmission system. The problem of the differences in the bandwidths of voltage and current probes causing an error in the calculation of energy dissipation was avoided by reducing the bandwidths of voltage and current measurements to the same value. The real discharge current was obtained by subtracting the capacitive current from the total current. The energy per pulse obtained in the reactor before and after improvement of the diagnostics and electrical circuit were 15.5 mJ and 26.8 mJ, respectively, and the energy efficiencies of MO degradation were 1.34 x 10 -9 mol/J and 1.95 x 10 -9 mol/J, respectively

  11. Analogue Electrical Circuit for Simulation of the Duffing-Holmes Equation

    DEFF Research Database (Denmark)

    Tamaseviciute, E.; Tamasevicius, A.; Mykolaitis, G.

    2008-01-01

    An extremely simple second order analogue electrical circuit for simulating the two-well Duffing-Holmes mathematical oscillator is described. Numerical results and analogue electrical simulations are illustrated with the snapshots of chaotic waveforms, phase portraits (Lissajous figures...

  12. Global Electricity Trade Network: Structures and Implications

    Science.gov (United States)

    Ji, Ling; Jia, Xiaoping; Chiu, Anthony S. F.; Xu, Ming

    2016-01-01

    Nations increasingly trade electricity, and understanding the structure of the global power grid can help identify nations that are critical for its reliability. This study examines the global grid as a network with nations as nodes and international electricity trade as links. We analyze the structure of the global electricity trade network and find that the network consists of four sub-networks, and provide a detailed analysis of the largest network, Eurasia. Russia, China, Ukraine, and Azerbaijan have high betweenness measures in the Eurasian sub-network, indicating the degrees of centrality of the positions they hold. The analysis reveals that the Eurasian sub-network consists of seven communities based on the network structure. We find that the communities do not fully align with geographical proximity, and that the present international electricity trade in the Eurasian sub-network causes an approximately 11 million additional tons of CO2 emissions. PMID:27504825

  13. Method of boundary testing of the electric circuits and its application for calculating electric tolerances. [electric equipment tests

    Science.gov (United States)

    Redkina, N. P.

    1974-01-01

    Boundary testing of electric circuits includes preliminary and limiting tests. Preliminary tests permit determination of the critical parameters causing the greatest deviation of the output parameter of the system. The boundary tests offer the possibility of determining the limits of the fitness of the system with simultaneous variation of its critical parameters.

  14. Application of group theory to proper vibrations in an electric circuit

    OpenAIRE

    Hosoya, Masahiko; 細谷, 将彦

    2010-01-01

    Group-theoretical analysis is first presented to three-dimensional behavior of an electric circuit. All the modes of proper vibration are found and assigned to each irreducible representation of symmetrical group of the circuit without solving its circuit equations. In order that an electromagnetic radiation from the outside may induce each vibration, a selection rule which is similar to that in infrared absorption must be fulfilled. The circuit may be used as a directive antenna.

  15. The Electron Runaround: Understanding Electric Circuit Basics through a Classroom Activity

    Science.gov (United States)

    Singh, Vandana

    2010-01-01

    Several misconceptions abound among college students taking their first general physics course, and to some extent pre-engineering physics students, regarding the physics and applications of electric circuits. Analogies used in textbooks, such as those that liken an electric circuit to a piped closed loop of water driven by a water pump, do not…

  16. Pre-Service and In-Service Physics Teachers' Ideas about Simple Electric Circuits

    Science.gov (United States)

    Kucukozer, Huseyin; Demirci, Neset

    2008-01-01

    The aim of the study is to determine pre-service and high school physics teachers' ideas about simple electric circuits. In this study, a test containing eight questions related to simple electric circuits was given to the pre-service physics teachers (32 subjects) that had graduated from Balikesir University, Necatibey Faculty of Education, the…

  17. Basic guidelines to introduce electric circuit simulation software in a general physics course

    Science.gov (United States)

    Moya, A. A.

    2018-05-01

    The introduction of electric circuit simulation software for undergraduate students in a general physics course is proposed in order to contribute to the constructive learning of electric circuit theory. This work focuses on the lab exercises based on dc, transient and ac analysis in electric circuits found in introductory physics courses, and shows how students can use the simulation software to do simple activities associated with a lab exercise itself and with related topics. By introducing electric circuit simulation programs in a general physics course as a brief activitiy complementing lab exercise, students develop basic skills in using simulation software, improve their knowledge on the topology of electric circuits and perceive that the technology contributes to their learning, all without reducing the time spent on the actual content of the course.

  18. New equivalent lumped electrical circuit for piezoelectric transformers.

    Science.gov (United States)

    Gonnard, Paul; Schmitt, P M; Brissaud, Michel

    2006-04-01

    A new equivalent circuit is proposed for a contour-vibration-mode piezoelectric transformer (PT). It is shown that the usual lumped equivalent circuit derived from the conventional Mason approach is not accurate. The proposed circuit, built on experimental measurements, makes an explicit difference between the elastic energies stored respectively on the primary and secondary parts. The experimental and theoretical resonance frequencies with the secondary in open or short circuit are in good agreement as well as the output "voltage-current" characteristic and the optimum efficiency working point. This circuit can be extended to various PT configurations and appears to be a useful tool for modeling electronic devices that integrate piezoelectric transformers.

  19. Effect of a Diagram on Primary Students' Understanding About Electric Circuits

    Science.gov (United States)

    Preston, Christine Margaret

    2017-09-01

    This article reports on the effect of using a diagram to develop primary students' conceptual understanding about electric circuits. Diagrammatic representations of electric circuits are used for teaching and assessment despite the absence of research on their pedagogical effectiveness with young learners. Individual interviews were used to closely analyse Years 3 and 5 (8-11-year-old) students' explanations about electric circuits. Data was collected from 20 students in the same school providing pre-, post- and delayed post-test dialogue. Students' thinking about electric circuits and changes in their explanations provide insights into the role of diagrams in understanding science concepts. Findings indicate that diagram interaction positively enhanced understanding, challenged non-scientific views and promoted scientific models of electric circuits. Differences in students' understanding about electric circuits were influenced by prior knowledge, meta-conceptual awareness and diagram conventions including a stylistic feature of the diagram used. A significant finding that students' conceptual models of electric circuits were energy rather than current based has implications for electricity instruction at the primary level.

  20. Unit: Electric Circuits, Inspection Pack, National Trial Print.

    Science.gov (United States)

    Australian Science Education Project, Toorak, Victoria.

    As a part of the unit materials in the series produced by the Australian Science Education Project, this teacher edition is primarily composed of a core relating to simple circuits, a test form, and options. Options are given under the headings: Your Invention; "How Long Does a Call Last?"; One, Two, Three Wires; Parallel Circuits; More…

  1. The creation of a global electricity market

    International Nuclear Information System (INIS)

    DePinto, D.; Anderson, A.

    1998-01-01

    The global embrace of market-based economics has led to significant growth and prosperity resulting in increased needs for electricity. The burgeoning demand for energy has created requirements for capital investment at time when the state-owned energy companies cannot provide it. Governments, busy trying to find ways to manage already inflated debt burdens, have little capacity for funding the capital needed to expand energy production. In these strategic industries, governments are beginning to embrace the principles of free market capitalism and private ownership, recognizing the significant benefits to be realized: reduced national deficits, a more efficient energy sector, access to foreign capital, greater internal capital generation, and more energy to fuel economic growth. This is driving the governments to embrace privatization and is creating a market for the sale of electric utilities. On the other side of this equation are the fast developing global electric companies that are prepared to expand in both developing and developed countries through significant acquisitions of either companies or strategic assets. This scenario is further enhanced as the Independent Power Developers chase projects from Brazil to China and bring competition to the development of new generation. Never before has there been such a movement to the complete transformation of the energy industry. Countries on every continent are exploring how they can reform and restructure the energy sector. The analysis will address: Global transformation sweeping the various regions of the world; Impact on developers and the strategy required for success; Global electric companies and their impact on the transformation process; and Future of the electric power industry: Will it bring the world closer together?

  2. Formalization, equivalence and generalization of basic resonance electrical circuits

    Science.gov (United States)

    Penev, Dimitar; Arnaudov, Dimitar; Hinov, Nikolay

    2017-12-01

    In the work are presented basic resonance circuits, which are used in resonance energy converters. The following resonant circuits are considered: serial, serial with parallel load parallel capacitor, parallel and parallel with serial loaded inductance. For the circuits under consideration, expressions are generated for the frequencies of own oscillations and for the equivalence of the active power emitted in the load. Mathematical expressions are graphically constructed and verified using computer simulations. The results obtained are used in the model based design of resonant energy converters with DC or AC output. This guaranteed the output indicators of power electronic devices.

  3. Students' Reasoning When Tackling Electric Field and Potential in Explanation of DC Resistive Circuits

    Science.gov (United States)

    Leniz, Ane; Zuza, Kristina; Guiasola, Jenaro

    2017-01-01

    This study examines the causal reasoning that university students use to explain how dc circuits work. We analyze how students use the concepts of electric field and potential difference in their explanatory models of dc circuits, and what kinds of reasoning they use at the macroscopic and microscopic levels in their explanations. This knowledge…

  4. Technological Literacy Learning with Cumulative and Stepwise Integration of Equations into Electrical Circuit Diagrams

    Science.gov (United States)

    Ozogul, G.; Johnson, A. M.; Moreno, R.; Reisslein, M.

    2012-01-01

    Technological literacy education involves the teaching of basic engineering principles and problem solving, including elementary electrical circuit analysis, to non-engineering students. Learning materials on circuit analysis typically rely on equations and schematic diagrams, which are often unfamiliar to non-engineering students. The goal of…

  5. High school physics teacher forms of thought about simple electric circuits

    International Nuclear Information System (INIS)

    Kucukozer, H.

    2005-01-01

    According to some researches on students and on science teachers, they have same conceptual difficulties about simple electric circuits and these affect their further learning or/and teaching. [2], [5], [8], [9], [11], [13]. The main aim of this study was to investigate in-service high school physics teachers form of thought about simple electric circuits. In this purpose a test that was developed by Kucukozer [7], contains eight questions related to simple electric circuits was applied to in-service physics teachers (25 subjects) in various Anatolian Teacher High School in Turkey. After analyzing and evaluating of their data, it was found that, the physics teachers have conceptual difficulties about simple electric circuits, especially the concepts about source of stationary current and current usage

  6. Experimental and numerical study of electrical crosstalk in photonic integrated circuits

    NARCIS (Netherlands)

    Yao, W.; Gilardi, G.; Calabretta, N.; Smit, M.K.; Wale, M.J.

    2015-01-01

    This paper presents measurement results on electrical crosstalk between interconnect lines and electro-optical phaseshifters in photonic integrated circuits. The results indicate that overall crosstalk originates from radiative and substrate coupling between lines and from shared ground connections.

  7. THE RATE OF CURRENT CHANGE DURING A SHORT CIRCUIT IN THE POWER CIRCUITS OF THE ELECTRIC ROLLING STOCK WITH REGARD TO EDDY CURRENTS

    Directory of Open Access Journals (Sweden)

    L. V. Dubinets

    2010-04-01

    Full Text Available In the article the issue of influence of vortical currents on rate of change of short circuit current is considered, a mathematical model for the calculation of short circuit currents in the traction mode in the power circuits of DC electric rolling stock is presented, and the research results are given.

  8. Electric Circuit Model Analogy for Equilibrium Lattice Relaxation in Semiconductor Heterostructures

    Science.gov (United States)

    Kujofsa, Tedi; Ayers, John E.

    2018-01-01

    The design and analysis of semiconductor strained-layer device structures require an understanding of the equilibrium profiles of strain and dislocations associated with mismatched epitaxy. Although it has been shown that the equilibrium configuration for a general semiconductor strained-layer structure may be found numerically by energy minimization using an appropriate partitioning of the structure into sublayers, such an approach is computationally intense and non-intuitive. We have therefore developed a simple electric circuit model approach for the equilibrium analysis of these structures. In it, each sublayer of an epitaxial stack may be represented by an analogous circuit configuration involving an independent current source, a resistor, an independent voltage source, and an ideal diode. A multilayered structure may be built up by the connection of the appropriate number of these building blocks, and the node voltages in the analogous electric circuit correspond to the equilibrium strains in the original epitaxial structure. This enables analysis using widely accessible circuit simulators, and an intuitive understanding of electric circuits can easily be extended to the relaxation of strained-layer structures. Furthermore, the electrical circuit model may be extended to continuously-graded epitaxial layers by considering the limit as the individual sublayer thicknesses are diminished to zero. In this paper, we describe the mathematical foundation of the electrical circuit model, demonstrate its application to several representative structures involving In x Ga1- x As strained layers on GaAs (001) substrates, and develop its extension to continuously-graded layers. This extension allows the development of analytical expressions for the strain, misfit dislocation density, critical layer thickness and widths of misfit dislocation free zones for a continuously-graded layer having an arbitrary compositional profile. It is similar to the transition from circuit

  9. Analysis of electrical circuits with variable load regime parameters projective geometry method

    CERN Document Server

    Penin, A

    2015-01-01

    This book introduces electric circuits with variable loads and voltage regulators. It allows to define invariant relationships for various parameters of regime and circuit sections and to prove the concepts characterizing these circuits. Generalized equivalent circuits are introduced. Projective geometry is used for the interpretation of changes of operating regime parameters. Expressions of normalized regime parameters and their changes are presented. Convenient formulas for the calculation of currents are given. Parallel voltage sources and the cascade connection of multi-port networks are d

  10. Josephson junction in the quantum mesoscopic electric circuits with charge discreteness

    Science.gov (United States)

    Pahlavani, H.

    2018-04-01

    A quantum mesoscopic electrical LC-circuit with charge discreteness including a Josephson junction is considered and a nonlinear Hamiltonian that describing the dynamic of such circuit is introduced. The quantum dynamical behavior (persistent current probability) is studied in the charge and phase regimes by numerical solution approaches. The time evolution of charge and current, number-difference and the bosonic phase and also the energy spectrum of a quantum mesoscopic electric LC-circuit with charge discreteness that coupled with a Josephson junction device are investigated. We show the role of the coupling energy and the electrostatic Coulomb energy of the Josephson junction in description of the quantum behavior and the spectral properties of a quantum mesoscopic electrical LC-circuits with charge discreteness.

  11. Variant of multimodal vibration damping of electroviscoelastic structures by appropriate choice of external electric circuit parameters

    Directory of Open Access Journals (Sweden)

    Dmitrii A. Oshmarin

    2016-09-01

    Full Text Available In technical applications it takes place the problem of vibration damping in certain regions of the structure, at the location of optical sensors for instance, at any external dynamic excitations with no mass increase and no changes in spectral portrait. In order to solve these problems it is widespread the use of special damping devices: piezoelectric elements connected to external electric circuits and attached to the structure. It became possible due to piezoelectric effect, which provides transformation of part of energy of vibrations into electric one, which is dissipated in external electric circuit. So that by using appropriate electric circuits one may dissipate internal energy and therefore reduce structural vibrations in definite frequency range. As a rule, external circuit of single branch, which shunts single piezoelectric element, allows vibration damping on one certain frequency. Due to the fact, that practical applications usually include requirements of damping of several modes by one and the same technical devices, the problem of multimodal vibration damping in smart-structures is rather acute. The objective of this paper is the study of possibility of vibration damping on several modes by using single external series RL-circuit, connected to electrodes of single piezoelectric element on the basis of solution of problems on natural and forced steady-state vibrations of electroelastic systems with external electric circuits.

  12. Physical and electrical characterization of corundum substrates and epitaxial silicon layers in view of fabricating integrated circuits

    International Nuclear Information System (INIS)

    Trilhe, J.; Legal, H.; Rolland, G.

    1975-01-01

    The S.O.S. technology (silicon on insulating substrate) allows compact, radiation hard, fast integrated circuits to be fabricated. It is noticeable that complex integrated circuits on corundum substrates obtained with various fabrication processes have various electrical characteristics. Possible correlations between the macroscopic defects of the substrate and the electrical characteristics of the circuit were investigated [fr

  13. The Use of Enhanced Guided Notes in an Electric Circuit Class: An Exploratory Study

    Science.gov (United States)

    Lawanto, O.

    2012-01-01

    This study was conducted to evaluate students' (n=70) learning performance after their participation in lectures using enhanced guided notes (EGN) in an electric circuits course for non-electrical engineering students. Unlike traditional guided notes, EGN include questions that prompt students to evaluate their metacognitive knowledge. The results…

  14. Conceptual understanding of electrical circuits in secondary vocational engineering education: combining traditional instruction with inquiry learning in a virtual lab

    NARCIS (Netherlands)

    Kolloffel, Bas Jan; de Jong, Anthonius J.M.

    2013-01-01

    Background: Traditionally, engineering curricula about electrical circuits use textbook instruction and hands-on lessons, which are effective approaches for teaching terms and definitions, the procedural use of formulas, and how to build circuits. Nonetheless, students often lack conceptual

  15. Design of pressure-driven microfluidic networks using electric circuit analogy.

    Science.gov (United States)

    Oh, Kwang W; Lee, Kangsun; Ahn, Byungwook; Furlani, Edward P

    2012-02-07

    This article reviews the application of electric circuit methods for the analysis of pressure-driven microfluidic networks with an emphasis on concentration- and flow-dependent systems. The application of circuit methods to microfluidics is based on the analogous behaviour of hydraulic and electric circuits with correlations of pressure to voltage, volumetric flow rate to current, and hydraulic to electric resistance. Circuit analysis enables rapid predictions of pressure-driven laminar flow in microchannels and is very useful for designing complex microfluidic networks in advance of fabrication. This article provides a comprehensive overview of the physics of pressure-driven laminar flow, the formal analogy between electric and hydraulic circuits, applications of circuit theory to microfluidic network-based devices, recent development and applications of concentration- and flow-dependent microfluidic networks, and promising future applications. The lab-on-a-chip (LOC) and microfluidics community will gain insightful ideas and practical design strategies for developing unique microfluidic network-based devices to address a broad range of biological, chemical, pharmaceutical, and other scientific and technical challenges.

  16. The Electron Runaround: Understanding Electric Circuit Basics Through a Classroom Activity

    Science.gov (United States)

    Singh, Vandana

    2010-05-01

    Several misconceptions abound among college students taking their first general physics course, and to some extent pre-engineering physics students, regarding the physics and applications of electric circuits. Analogies used in textbooks, such as those that liken an electric circuit to a piped closed loop of water driven by a water pump, do not completely resolve these misconceptions. Mazur and Knight,2 in particular, separately note that such misconceptions include the notion that electric current on either side of a light bulb in a circuit can be different. Other difficulties and confusions involve understanding why the current in a parallel circuit exceeds the current in a series circuit with the same components, and include the role of the battery (where students may assume wrongly that a dry cell battery is a fixed-current rather than a fixed-voltage device). A simple classroom activity that students can play as a game can resolve these misconceptions, providing an intellectual as well as a hands-on understanding. This paper describes the "Electron Runaround," first developed by the author to teach extremely bright 8-year-old home-schooled children the basics of electric circuits and subsequently altered (according to the required level of instruction) and used for various college physics courses.

  17. THE ANALYSIS OF STRUCTURAL RELIABILITY OF THE MAIN ELECTRIC CONNECTION CIRCUITS OF NUCLEAR POWER PLANTS

    Directory of Open Access Journals (Sweden)

    M. A. Korotkevich

    2017-01-01

    Full Text Available The reliability of the main circuit of electrical connections at a nuclear electric power plant that has two units with a capacity of 1,200 MW each has been determined. Reliability, economical, maneuverable properties of the atomic power plant under study are largely determined by its main circuit, so the choice of the circuit for the design and its status in the process of operation occur to be critical objectives. Main electrical connection circuits in nuclear electric power plants are selected on the basis of the schematic networks of the energy system and the land attached to the plant. The circuit of the connection of a nuclear power plant to the grid in the original normal operating modes at all stages of the construction of such a plant should provide the outcome of the full added capacity of a nuclear power plant and the preservation of its stability in the power system without the influence of the emergency system automatics when any outgoing transmission line is disabled. When selecting the main circuit the individual capacity of the installed units and their number are taken into account as well as the order of development of the plant and power supply system; the voltage on which the power of a plant is delivered; a shortcircuit current for switchgear high voltage and the need for their limitation by circuit means; the most power that can be lost when damage to any switch. A model of reliability of the main circuit of electrical connections is designed to detect all types of accidents that are possible at the coincidence of failures of elements with the repair and operational modes that differs in composition and damageability of the equipment, as well as under conditions of the development of accidents due to failure of operation of devices of relay protection and automation.

  18. Electrical Quality Assurance of the Superconducting Circuits during LHC Machine Assembly

    CERN Document Server

    Bozzini, D; Desebe, O; Mess, K H; Russenschuck, Stephan; Bednarek, M; Dworak, D; Górnicki, E; Jurkiewicz, P; Kapusta, P; Kotarba, A; Ludwin, J; Olek, S; Talach, M; Zieblinski, M; Klisch, M; Prochal, B

    2008-01-01

    Based on the LHC powering reference database, all-together 1750 superconducting circuits were connected in the various cryogenic transfer lines of the LHC machine. Testing the continuity, magnet polarity, and the quality of the electrical insulation were the main tasks of the Electrical Quality Assurance (ELQA) activities during the LHC machine assembly. With the assembly of the LHC now complete, the paper reviews the work flow, resources, and the qualification results including the different types of electrical non-conformities.

  19. Measuring user similarity using electric circuit analysis: application to collaborative filtering.

    Science.gov (United States)

    Yang, Joonhyuk; Kim, Jinwook; Kim, Wonjoon; Kim, Young Hwan

    2012-01-01

    We propose a new technique of measuring user similarity in collaborative filtering using electric circuit analysis. Electric circuit analysis is used to measure the potential differences between nodes on an electric circuit. In this paper, by applying this method to transaction networks comprising users and items, i.e., user-item matrix, and by using the full information about the relationship structure of users in the perspective of item adoption, we overcome the limitations of one-to-one similarity calculation approach, such as the Pearson correlation, Tanimoto coefficient, and Hamming distance, in collaborative filtering. We found that electric circuit analysis can be successfully incorporated into recommender systems and has the potential to significantly enhance predictability, especially when combined with user-based collaborative filtering. We also propose four types of hybrid algorithms that combine the Pearson correlation method and electric circuit analysis. One of the algorithms exceeds the performance of the traditional collaborative filtering by 37.5% at most. This work opens new opportunities for interdisciplinary research between physics and computer science and the development of new recommendation systems.

  20. Measuring user similarity using electric circuit analysis: application to collaborative filtering.

    Directory of Open Access Journals (Sweden)

    Joonhyuk Yang

    Full Text Available We propose a new technique of measuring user similarity in collaborative filtering using electric circuit analysis. Electric circuit analysis is used to measure the potential differences between nodes on an electric circuit. In this paper, by applying this method to transaction networks comprising users and items, i.e., user-item matrix, and by using the full information about the relationship structure of users in the perspective of item adoption, we overcome the limitations of one-to-one similarity calculation approach, such as the Pearson correlation, Tanimoto coefficient, and Hamming distance, in collaborative filtering. We found that electric circuit analysis can be successfully incorporated into recommender systems and has the potential to significantly enhance predictability, especially when combined with user-based collaborative filtering. We also propose four types of hybrid algorithms that combine the Pearson correlation method and electric circuit analysis. One of the algorithms exceeds the performance of the traditional collaborative filtering by 37.5% at most. This work opens new opportunities for interdisciplinary research between physics and computer science and the development of new recommendation systems.

  1. Electrical breakthrough effect for end pointing in 90 and 45 nm node circuit edit

    International Nuclear Information System (INIS)

    Liu, Kun; Soskov, Alex; Scipioni, Larry; Bassom, Neil; Sijbrandij, Sybren; Smith, Gerald

    2006-01-01

    The interaction between high-energy Ga + ions and condensed matter is studied for circuit edit applications. A new 'electrical breakthrough effect' due to charging of, and Ga + penetration/doping into, dielectrics is discovered. This new effect is proposed for end pointing in 90 and 45 nm node circuit edits where integrated circuit device dimensions are of a few hundred nanometers. This new end point approach is very sensitive, reliable, and precise. Most importantly, it is not sensitive to device dimensions. A series of circuit edits involving milling holes of high aspect ratio (5-30) and small cross-section area (0.01-0.25 μm 2 ) on real chips has been successfully performed using the electrical breakthrough effect as the end point method

  2. Joule-Thief Circuit Performance for Electricity Energy Saving of Emergency Lamps

    Science.gov (United States)

    Nuryanto Budisusila, Eka; Arifin, Bustanul

    2017-04-01

    The alternative energy such as battery as power source is required as energy source failures. The other need is outdoor lighting. The electrical power source is expected to be a power saving, optimum and has long life operating. The Joule-Thief circuit is one of solution method for energy saving by using raised electromagnetic force on cored coil when there is back-current. This circuit has a transistor operated as a switch to cut voltage and current flowing along the coils. The present of current causing magnetic induction and generates energy. Experimental prototype was designed by using battery 1.5V to activate Light Emitting Diode or LED as load. The LED was connected in parallel or serial circuit configuration. The result show that the joule-thief circuit able to supply LED circuits up to 40 LEDs.

  3. In situ testing of the Shippingport Atomic Power Station electrical circuits

    International Nuclear Information System (INIS)

    Dinsel, M.R.; Donaldson, M.R.; Soberano, F.T.

    1987-04-01

    This report discusses the results of electrical in situ testing of selected circuits and components at the Shippingport Atomic Power Station in Shippingport, Pennsylvania. Testing was performed by EG and G Idaho in support of the United States Nuclear Regulatory Commission (USNRC) Nuclear Plant Aging Research (NPAR) Program. The goal was to determine the extent of aging or degradation of various circuits from the original plant, and the two major coreplant upgrades (representing three distinct age groups), as well as to evaluate previously developed surveillance technology. The electrical testing was performed using the Electrical Circuit Characterization and Diagnostic (ECCAD) system developed by EG and G for the US Department of Energy to use at TMI-2. Testing included measurements of voltage, effective series capacitance, effective series inductance, impedance, effective series resistance, dc resistance, insulation resistance and time domain reflectometry (TDR) parameters. The circuits evaluated included pressurizer heaters, control rod position indicator cables, miscellaneous primary system Resistance Temperature Detectors (RTDs), nuclear instrumentation cables, and safety injection system motor operated valves. It is to be noted that the operability of these circuits was tested after several years had elapsed because plant operations had concluded at Shippingport. There was no need following plant shutdown to retain the circuits in working condition, so no effort was expended for that purpose. The in situ measurements and analysis of the data confirmed the effectiveness of the ECCAD system for detecting degradation of circuit connections and splices because of high resistance paths, with most of the problems caused by corrosion. Results indicate a correlation between the chronological age of circuits and circuit degradation

  4. Crisis induced intermittency in a fourth-order autonomous electric circuit

    International Nuclear Information System (INIS)

    Stouboulos, I.N.; Miliou, A.N.; Valaristos, A.P.; Kyprianidis, I.M.; Anagnostopoulos, A.N.

    2007-01-01

    The chaotic dynamics of a fourth-order autonomous nonlinear electric circuit has been studied. The circuit consists of two active elements, one linear negative conductance and one nonlinear resistor exhibiting a symmetrical piecewise-linear v-i characteristic and two capacitances C 1 and C 2 , which serve as the control parameters of the system. Experimental time series and the corresponding phase portraits were used to register the intermittent behaviour of the corresponding dynamical system between two interacting subattractors. The distribution of the times τ, between successive transitions from the one subattractor to the other indicates that a crisis induced intermittency occurs in the studied circuit

  5. New equivalent-electrical circuit model and a practical measurement method for human body impedance.

    Science.gov (United States)

    Chinen, Koyu; Kinjo, Ichiko; Zamami, Aki; Irei, Kotoyo; Nagayama, Kanako

    2015-01-01

    Human body impedance analysis is an effective tool to extract electrical information from tissues in the human body. This paper presents a new measurement method of impedance using armpit electrode and a new equivalent circuit model for the human body. The lowest impedance was measured by using an LCR meter and six electrodes including armpit electrodes. The electrical equivalent circuit model for the cell consists of resistance R and capacitance C. The R represents electrical resistance of the liquid of the inside and outside of the cell, and the C represents high frequency conductance of the cell membrane. We propose an equivalent circuit model which consists of five parallel high frequency-passing CR circuits. The proposed equivalent circuit represents alpha distribution in the impedance measured at a lower frequency range due to ion current of the outside of the cell, and beta distribution at a high frequency range due to the cell membrane and the liquid inside cell. The calculated values by using the proposed equivalent circuit model were consistent with the measured values for the human body impedance.

  6. Factors influencing the reliability of non-electric detonating circuit in underground uranium mines and preventive measures of misfiring

    International Nuclear Information System (INIS)

    Li Qin

    2010-01-01

    Characteristics of non-electric detonating circuit are introduced. The main factors influencing the reliability of non-electric detonating circuit are described. Taking an underground blasting of a uranium mine for example, the reliability of various kinds of detonating network system is calculated using the reliability theory and numerical analysis method. The reasons that cause the misfiring in non-electric detonating circuit system are analyzed, and preventive measures are put forward.(authors)

  7. Hydraulically-activated operating system for an electric circuit breaker

    Science.gov (United States)

    Imam, Imdad; Barkan, Philip

    1979-01-01

    This operating system comprises a fluid motor having a piston, a breaker-opening space at one side of the piston, and a breaker-closing space at its opposite side. An accumulator freely communicates with the breaker-opening space for supplying pressurized fluid thereto during a circuit-breaker opening operation. A normally-closed valve located on the breaker-closing-side of the piston is openable to release liquid from the breaker-closing space so that pressurized liquid in the breaker-opening space can drive the piston in an opening direction. Means is provided for restoring the valve to its closed position following the circuit-breaker opening operation. An impeded passage affords communication between the accumulator and the breaker-closing space to allow pressurized liquid to flow from the accumulator to the breaker-closing space and develop a pressure therein substantially equal to accumulator pressure when the valve is restored to closed position following breaker-opening. This passage is so impeded that the flow therethrough from the accumulator into the breaker-closing space is sufficiently low during initial opening motion of the piston through a substantial portion of its opening stroke as to avoid interference with said initial opening motion of the piston.

  8. Hydraulically-actuated operating system for an electric circuit breaker

    Science.gov (United States)

    Barkan, Philip; Imam, Imdad

    1978-01-01

    This hydraulically-actuated operating system comprises a cylinder, a piston movable therein in an opening direction to open a circuit breaker, and an accumulator for supplying pressurized liquid to a piston-actuating space within the cylinder. A normally-closed valve between the accumulator and the actuating space is openable to allow pressurized liquid from the accumulator to flow through the valve into the actuating space to drive the piston in an opening direction. A vent is located hydraulically between the actuating space and the valve for affording communication between said actuating space and a low pressure region. Flow control means is provided for restricting leakage through said vent to a rate that prevents said leakage from substantially detracting from the development of pressure within said actuatng space during the period from initial opening of the valve to the time when said piston has moved through most of its opening stroke. Following such period and while the valve is still open, said flow control means allows effective leakage through said vent. The accumulator has a limited capacity that results in the pressure within said actuating space decaying promptly to a low value as a result of effective leakage through said vent after the piston has moved through a circuit-breaker opening stroke and while the valve is in its open state. Means is provided for resetting the valve to its closed state in response to said pressure decay in the actuating space.

  9. Development of 3-D Mechanical Models of Electric Circuits and Their Effect on Students' Understanding of Electric Potential Difference

    Science.gov (United States)

    Balta, Nuri

    2015-01-01

    Visualizing physical concepts through models is an essential method in many sciences. While students are mostly proficient in handling mathematical aspects of problems, they frequently lack the ability to visualize and interpret abstract physical concepts in a meaningful way. In this paper, initially the electric circuits and related concepts were…

  10. Experience with the Quality Assurance of the Superconducting Electrical Circuits of the LHC Machine

    CERN Document Server

    Bozzini, D; Kotarba, A; Mess, Karl Hubert; Olek, S; Russenschuck, Stephan

    2006-01-01

    The coherence between the powering reference database for the LHC and the Electrical Quality Assurance (ELQA) is guaranteed on the procedural level. However, a challenge remains the coherence between the database, the magnet test and assembly procedures, and the connection of all superconducting circuits in the LHC machine. In this paper, the methods, tooling, and procedures for the ELQA during the assembly phase of the LHC will be presented in view of the practical experience gained in the LHC tunnel. Some examples of detected polarity errors and electrical non-conformities will be presented. The parameters measured at ambient temperature, such as the dielectric insulation of circuits, will be discussed.

  11. Surface charges and J H Poynting’s disquisitions on energy transfer in electrical circuits

    Science.gov (United States)

    Matar, M.; Welti, R.

    2017-11-01

    In this paper we review applications given by J H Poynting (1884) on the transfer of electromagnetic energy in DC circuits. These examples were strongly criticized by O Heaviside (1887). Heaviside stated that Poynting had a misconception about the nature of the electric field in the vicinity of a wire through which a current flows. The historical review of this conflict and its resolution based on the consideration of electrical charges on the surface of the wires can be useful for student courses on electromagnetism or circuit theory.

  12. Optimal design of RTCs in digital circuit fault self-repair based on global signal optimization

    Institute of Scientific and Technical Information of China (English)

    Zhang Junbin; Cai Jinyan; Meng Yafeng

    2016-01-01

    Since digital circuits have been widely and thoroughly applied in various fields, electronic systems are increasingly more complicated and require greater reliability. Faults may occur in elec-tronic systems in complicated environments. If immediate field repairs are not made on the faults, elec-tronic systems will not run normally, and this will lead to serious losses. The traditional method for improving system reliability based on redundant fault-tolerant technique has been unable to meet the requirements. Therefore, on the basis of (evolvable hardware)-based and (reparation balance technology)-based electronic circuit fault self-repair strategy proposed in our preliminary work, the optimal design of rectification circuits (RTCs) in electronic circuit fault self-repair based on global sig-nal optimization is deeply researched in this paper. First of all, the basic theory of RTC optimal design based on global signal optimization is proposed. Secondly, relevant considerations and suitable ranges are analyzed. Then, the basic flow of RTC optimal design is researched. Eventually, a typical circuit is selected for simulation verification, and detailed simulated analysis is made on five circumstances that occur during RTC evolution. The simulation results prove that compared with the conventional design method based RTC, the global signal optimization design method based RTC is lower in hardware cost, faster in circuit evolution, higher in convergent precision, and higher in circuit evolution success rate. Therefore, the global signal optimization based RTC optimal design method applied in the elec-tronic circuit fault self-repair technology is proven to be feasible, effective, and advantageous.

  13. Successfully Mapping the U-Tank to an Electric Circuit

    Science.gov (United States)

    Hong, Seok-In

    2010-01-01

    Water-flow analogies are helpful in understanding electricity. For example, in the Lodge model, the constant DC voltage source (a battery) is represented by a U-tank with two water columns of the same cross-sectional area connected by a horizontal duct in which a pump is installed. The pump maintains the difference of the levels of the two water…

  14. Estimating the Probability of Electrical Short Circuits from Tin Whiskers. Part 2

    Science.gov (United States)

    Courey, Karim J.; Asfour, Shihab S.; Onar, Arzu; Bayliss, Jon A.; Ludwig, Larry L.; Wright, Maria C.

    2010-01-01

    To comply with lead-free legislation, many manufacturers have converted from tin-lead to pure tin finishes of electronic components. However, pure tin finishes have a greater propensity to grow tin whiskers than tin-lead finishes. Since tin whiskers present an electrical short circuit hazard in electronic components, simulations have been developed to quantify the risk of said short circuits occurring. Existing risk simulations make the assumption that when a free tin whisker has bridged two adjacent exposed electrical conductors, the result is an electrical short circuit. This conservative assumption is made because shorting is a random event that had an unknown probability associated with it. Note however that due to contact resistance electrical shorts may not occur at lower voltage levels. In our first article we developed an empirical probability model for tin whisker shorting. In this paper, we develop a more comprehensive empirical model using a refined experiment with a larger sample size, in which we studied the effect of varying voltage on the breakdown of the contact resistance which leads to a short circuit. From the resulting data we estimated the probability distribution of an electrical short, as a function of voltage. In addition, the unexpected polycrystalline structure seen in the focused ion beam (FIB) cross section in the first experiment was confirmed in this experiment using transmission electron microscopy (TEM). The FIB was also used to cross section two card guides to facilitate the measurement of the grain size of each card guide's tin plating to determine its finish .

  15. Wireless Sensing System Using Open-circuit, Electrically-conductive Spiral-trace Sensor

    Science.gov (United States)

    Woodard, Stanley E. (Inventor); Taylor, Bryant D. (Inventor)

    2013-01-01

    A wireless sensing system includes a sensor made from an electrical conductor shaped to form an open-circuit, electrically-conductive spiral trace having inductance and capacitance. In the presence of a time-varying magnetic field, the sensor resonates to generate a harmonic response having a frequency, amplitude and bandwidth. A magnetic field response recorder wirelessly transmits the time-varying magnetic field to the sensor and wirelessly detects the sensor's response frequency, amplitude and bandwidth.

  16. Equivalent circuit and characteristic simulation of a brushless electrically excited synchronous wind power generator

    Science.gov (United States)

    Wang, Hao; Zhang, Fengge; Guan, Tao; Yu, Siyang

    2017-09-01

    A brushless electrically excited synchronous generator (BEESG) with a hybrid rotor is a novel electrically excited synchronous generator. The BEESG proposed in this paper is composed of a conventional stator with two different sets of windings with different pole numbers, and a hybrid rotor with powerful coupling capacity. The pole number of the rotor is different from those of the stator windings. Thus, an analysis method different from that applied to conventional generators should be applied to the BEESG. In view of this problem, the equivalent circuit and electromagnetic torque expression of the BEESG are derived on the basis of electromagnetic relation of the proposed generator. The generator is simulated and tested experimentally using the established equivalent circuit model. The experimental and simulation data are then analyzed and compared. Results show the validity of the equivalent circuit model.

  17. Integrated electric circuit engineering system in LSI design center, Konami Kogyo Co. Ltd

    Energy Technology Data Exchange (ETDEWEB)

    Kamitsuki, Kagehiko; Tanaka, Tomiaki

    1988-08-26

    Development of the integrated engineering system is presented which designs and manufactures the hardwares, softwares and cases of electronic game products with LSI integratedly as an experiment. The system is intended to reduce the number of each development of the parts, to verify each other by comparing each parts with the product concept during the development, to reduce modifications, and to shorten development periods. The main subsystems are an electric circuit CAD for LSI designs and a mechanical CAD for case or printed circuit board designs. The LSI development period has been shortened up to one month by a larger capacity computer and higher speed simulator, and the electric circuit engineering system capable of keeping step with the software development has been approximately completed. In the future, the system will be intended to introduce an expert system or a visual system capable of predicting the final product during a logical design period. (10 figs, 1 photo)

  18. The Effect of Herrmann Whole Brain Teaching Method on Students' Understanding of Simple Electric Circuits

    Science.gov (United States)

    Bawaneh, Ali Khalid Ali; Nurulazam Md Zain, Ahmad; Salmiza, Saleh

    2011-01-01

    The purpose of this study was to investigate the effect of Herrmann Whole Brain Teaching Method over conventional teaching method on eight graders in their understanding of simple electric circuits in Jordan. Participants (N = 273 students; M = 139, F = 134) were randomly selected from Bani Kenanah region-North of Jordan and randomly assigned to…

  19. Identifying and Investigating Difficult Concepts in Engineering Mechanics and Electric Circuits. Research Brief

    Science.gov (United States)

    Streveler, Ruth; Geist, Monica; Ammerman, Ravel; Sulzbach, Candace; Miller, Ronald; Olds, Barbara; Nelson, Mary

    2007-01-01

    This study extends ongoing work to identify difficult concepts in thermal and transport science and measure students' understanding of those concepts via a concept inventory. Two research questions provided the focal point: "What important concepts in electric circuits and engineering mechanics do students find difficult to learn?" and…

  20. An Analysis of Science Textbooks for Grade 6: The Electric Circuit Lesson

    Science.gov (United States)

    Sothayapetch, Pavinee; Lavonen, Jari; Juuti, Kalle

    2013-01-01

    Textbooks are a major tool in the teaching and learning process. This paper presents the results of an analysis of the Finnish and Thai 6th grade science textbooks: electric circuit lesson. Textual and pictorial information from the textbooks were analyzed under four main categories: 1) introduction of the concepts, 2) type of knowledge, 3)…

  1. Questions about Answers: Probing Teachers' Awareness and Planned Remediation of Learners' Misconceptions about Electric Circuits

    Science.gov (United States)

    Gaigher, Estelle

    2014-01-01

    This article reports an exploratory multi-case study on how science teachers understand and envisage addressing learners' misconceptions about electric circuits. Four teachers from schools in and around a large South African city participated in the study. An open-ended questionnaire was designed in a novel way, questioning teachers about wrong…

  2. Creating a Simple Electric Circuit with Children between the Ages of Five and Six

    Science.gov (United States)

    Kada, Vasiliki; Ravanis, Kostantinos

    2016-01-01

    This paper presents a study of how preschool-aged children go about creating and operating a simple electric circuit (wires, light bulb, and battery), and how they view the elements that comprise it, particularly how they view the role of the battery. The research involved 108 children aged between five and six, who were individually interviewed.…

  3. Development of a Three-Tier Test to Assess Misconceptions about Simple Electric Circuits

    Science.gov (United States)

    Pesman, Haki; Eryilmaz, Ali

    2010-01-01

    The authors aimed to propose a valid and reliable diagnostic instrument by developing a three-tier test on simple electric circuits. Based on findings from the interviews, open-ended questions, and the related literature, the test was developed and administered to 124 high school students. In addition to some qualitative techniques for…

  4. Encountering the Expertise Reversal Effect with a Computer-Based Environment on Electrical Circuit Analysis

    Science.gov (United States)

    Reisslein, Jana; Atkinson, Robert K.; Seeling, Patrick; Reisslein, Martin

    2006-01-01

    This study examined the effectiveness of a computer-based environment employing three example-based instructional procedures (example-problem, problem-example, and fading) to teach series and parallel electrical circuit analysis to learners classified by two levels of prior knowledge (low and high). Although no differences between the…

  5. Comparison of Parametrization Techniques for an Electrical Circuit Model of Lithium-Sulfur Batteries

    DEFF Research Database (Denmark)

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

    2015-01-01

    on the comparison of different parametrization methods of electrical circuit models (ECMs) for Li-S batteries. These methods are used to parametrize an ECM based on laboratory measurements performed on a Li-S pouch cell. Simulation results of ECMs are presented and compared against measurement values...

  6. EQUATIONS OF ELECTRIC MOTOR POWER SUPPLY UNIT DISSYMMETRY UNDER PHASE SHORT-CIRCUIT FAULT

    Directory of Open Access Journals (Sweden)

    V.Y. Tchaban

    2013-04-01

    Full Text Available In the paper, a formula is introduced for calculating electric motor supply unit voltage under feeding by a common transformer in the condition of a phase short-circuit in one of the motors. The formula is used in every time step of electromechanical state equations integration.

  7. Text Based Analogy in Overcoming Student Misconception on Simple Electricity Circuit Material

    Science.gov (United States)

    Hesti, R.; Maknun, J.; Feranie, S.

    2017-09-01

    Some researcher have found that the use of analogy in learning and teaching physics was effective enough in giving comprehension in a complicated physics concept such as electrical circuits. Meanwhile, misconception become main cause that makes students failed when learning physics. To provide teaching physics effectively, the misconception should be resolved. Using Text Based Analogy is one of the way to identifying misconceptions and it is enough to assist teachers in conveying scientific truths in order to overcome misconceptions. The purpose of the study to investigate the use of text based analogy in overcoming students misconception on simple electrical circuit material. The samples of this research were 28 of junior high school students taken purposively from one high school in South Jakarta. The method use in this research is pre-experimental and design in one shot case study. Students who are the participants of sample have been identified misconception on the electrical circuit material by using the Diagnostic Test of Simple Electricity Circuit. The results of this study found that TBA can replace the misconceptions of the concept possessed by students with scientific truths conveyed in the text in a way that is easily understood so that TBA is strongly recommended to use in other physics materials.

  8. Electrical impedance tomography system: an open access circuit design

    Directory of Open Access Journals (Sweden)

    Soleimani Manuchehr

    2006-05-01

    Full Text Available Abstract Background This paper reports a simple 2-D system for electrical impedance tomography EIT, which works efficiently and is low cost. The system has been developed in the Sharif University of Technology Tehran-Iran (for the author's MSc Project. Methods The EIT system consists of a PC in which an I/O card is installed with an external current generator, a multiplexer, a power supply and a phantom with an array of electrodes. The measurement system provides 12-bit accuracy and hence, suitable data acquisition software has been prepared accordingly. The synchronous phase detection method has been implemented for voltage measurement. Different methods of image reconstruction have been used with this instrument to generate electrical conductivity images. Results The results of simulation and real measurement of the system are presented. The reconstruction programs were written in MATLAB and the data acquisition software in C++. The system has been tested with both static and dynamic mode in a 2-D domain. Better results have been produced in the dynamic mode of operation, due to the cancellation of errors. Conclusion In the spirit of open access publication the design details of this simple EIT system are made available here.

  9. A Comparison of Experienced and Preservice Elementary School Teachers' Content Knowledge and Pedagogical Content Knowledge about Electric Circuits

    Science.gov (United States)

    Lin, Jing-Wen

    2017-01-01

    This study investigated the differences between Taiwanese experienced and preservice elementary school science teachers' content knowledge (CK) about electric circuits and their ability to predict students' preconceptions about electric circuits as an indicator of their pedagogical content knowledge (PCK). An innovative web-based recruitment and…

  10. Linear electrical circuits. Definitions - General theorems; Circuits electriques lineaires. Definitions - Theoremes generaux

    Energy Technology Data Exchange (ETDEWEB)

    Escane, J.M. [Ecole Superieure d' Electricite, 91 - Gif-sur-Yvette (France)

    2005-04-01

    The first part of this article defines the different elements of an electrical network and the models to represent them. Each model involves the current and the voltage as a function of time. Models involving time functions are simple but their use is not always easy. The Laplace transformation leads to a more convenient form where the variable is no more directly the time. This transformation leads also to the notion of transfer function which is the object of the second part. The third part aims at defining the fundamental operation rules of linear networks, commonly named 'general theorems': linearity principle and superimposition theorem, duality principle, Thevenin theorem, Norton theorem, Millman theorem, triangle-star and star-triangle transformations. These theorems allow to study complex power networks and to simplify the calculations. They are based on hypotheses, the first one is that all networks considered in this article are linear. (J.S.)

  11. Carbon emission intensity in electricity production: A global analysis

    International Nuclear Information System (INIS)

    Ang, B.W.; Su, Bin

    2016-01-01

    We study changes in the aggregate carbon intensity (ACI) for electricity at the global and country levels. The ACI is defined as the energy-related CO_2 emissions in electricity production divided by the electricity produced. It is a performance indicator since a decrease in its value is a desirable outcome from the environmental and climate change viewpoints. From 1990 to 2013, the ACI computed at the global level decreased only marginally. However, fairly substantial decreases were observed in many countries. This apparent anomaly arises from a geographical shift in global electricity production with countries having a high ACI increasingly taking up a larger electricity production share. It is found that globally and in most major electricity producing countries, reduction in their ACI was due mainly to improvements in the thermal efficiency of electricity generation rather than to fuel switching. Estimates of the above-mentioned effects are made using LMDI decomposition analysis. Our study reveals several challenges in reducing global CO_2 emissions from the electricity production sector although technically the reduction potential for the sector is known to be great. - Highlights: •Variations of aggregate carbon intensity (ACI) for electricity of world countries are analysed. •Main drivers of changes in ACI of major electricity producing countries are studied using index decomposition analysis. •Geographical shift in electricity production had a significant impact on global ACI. •Improvements in the thermal efficiency of generation were the main driver of reduction in ACI.

  12. Theoretical modeling and equivalent electric circuit of a bimorph piezoelectric micromachined ultrasonic transducer.

    Science.gov (United States)

    Sammoura, Firas; Kim, Sang-Gook

    2012-05-01

    An electric circuit model for a circular bimorph piezoelectric micromachined ultrasonic transducer (PMUT) was developed for the first time. The model was made up of an electric mesh, which was coupled to a mechanical mesh via a transformer element. The bimorph PMUT consisted of two piezoelectric layers of the same material, having equal thicknesses, and sandwiched between three thin electrodes. The piezoelectric layers, having the same poling axis, were biased with electric potentials of the same magnitude but opposite polarity. The strain mismatches between the two layers created by the converse piezoelectric effect caused the membrane to vibrate and, hence, transmit a pressure wave. Upon receiving the echo of the acoustic wave, the membrane deformation led to the generation of electric charges as a result of the direct piezoelectric phenomenon. The membrane angular velocity and electric current were related to the applied electric field, the impinging acoustic pressure, and the moment at the edge of the membrane using two canonical equations. The transduction coefficients from the electrical to the mechanical domain and vice-versa were shown to be bilateral and the system was shown to be reversible. The circuit parameters of the derived model were extracted, including the transformer ratio, the clamped electric impedance, the spring-softening impedance, and the open-circuit mechanical impedance. The theoretical model was fully examined by generating the electrical input impedance and average plate displacement curves versus frequency under both air and water loading conditions. A PMUT composed of piezoelectric material with a lossy dielectric was also investigated and the maximum possible electroacoustical conversion efficiency was calculated.

  13. Understanding the Pathophysiology of Portosystemic Shunt by Simulation Using an Electric Circuit.

    Science.gov (United States)

    Kim, Moonhwan; Lee, Keon-Young

    2016-01-01

    Portosystemic shunt (PSS) without a definable cause is a rare condition, and most of the studies on this topic are small series or based on case reports. Moreover, no firm agreement has been reached on the definition and classification of various forms of PSS, which makes it difficult to compare and analyze the management. The blood flow can be seen very similar to an electric current, governed by Ohm's law. The simulation of PSS using an electric circuit, combined with the interpretation of reported management results, can provide intuitive insights into the underlying mechanism of PSS development. In this article, we have built a model of PSS using electric circuit symbols and explained clinical manifestations as well as the possible mechanisms underlying a PSS formation.

  14. Electrical characterization and an equivalent circuit model of a microhollow cathode discharge reactor

    International Nuclear Information System (INIS)

    Taylan, O.; Berberoglu, H.

    2014-01-01

    This paper reports the electrical characterization and an equivalent circuit of a microhollow cathode discharge (MHCD) reactor in the self-pulsing regime. A MHCD reactor was prototyped for air plasma generation, and its current-voltage characteristics were measured experimentally in the self-pulsing regime for applied voltages from 2000 to 3000 V. The reactor was modeled as a capacitor in parallel with a variable resistor. A stray capacitance was also introduced to the circuit model to represent the capacitance of the circuit elements in the experimental setup. The values of the resistor and capacitors were recovered from experimental data, and the proposed circuit model was validated with independent experiments. Experimental data showed that increasing the applied voltage increased the current, self-pulsing frequency and average power consumption of the reactor, while it decreased the peak voltage. The maximum and the minimum voltages obtained using the model were in agreement with the experimental data within 2.5%, whereas the differences between peak current values were less than 1%. At all applied voltages, the equivalent circuit model was able to accurately represent the peak and average power consumption as well as the self-pulsing frequency within the experimental uncertainty. Although the results shown in this paper was for atmospheric air pressures, the proposed equivalent circuit model of the MHCD reactor could be generalized for other gases at different pressures.

  15. Background voltage distortion influence on power electric systems in the presence of the Steinmetz circuit

    Energy Technology Data Exchange (ETDEWEB)

    Sainz, Luis; Pedra, Joaquin [Department of Electrical Engineering, ETSEIB-UPC, Av. Diagonal 647, 08028 Barcelona (Spain); Caro, Manuel [IDOM Ingenieria y Arquitectura, C. Barcas 2, 46002 Valencia (Spain)

    2009-01-15

    In traction systems, it is usual to connect reactances in delta configuration with single-phase loads to reduce voltage unbalances and avoid electric system operation problems. This set is known as Steinmetz circuit. Parallel and series resonances can occur due to the capacitive reactance of the Steinmetz circuit and affect power quality. In this paper, the series resonance ''observed'' from the supply system is numerically located. The study of this resonance is important to avoid problems due to background voltage distortion. Experimental measurements are also presented to validate the obtained numerical results. (author)

  16. Importance of Practical Relevance and Design Modules in Electrical Circuits Education

    Directory of Open Access Journals (Sweden)

    Kalpathy Sundaram

    2011-05-01

    Full Text Available The interactive technical electronic book, TechEBook, currently under development at the University of Central Florida (UCF, provides a useful tool for engineers and scientists through unique features compared to the most used traditional electrical circuit textbooks available in the market. TechEBook has comprised the two worlds of classical circuit books and an interactive operating platform such as iPads, laptops and desktops utilizing Java Virtual Machine operator. The TechEBook provides an interactive applets screen that holds many modules, in which each had a specific application in the self learning process. This paper describes two of the interactive techniques in the TechEBook known as, Practical Relevance Modules (PRM and Design Modules (DM. The Practical Relevance Module will assist the readers to learn electrical circuit analysis and to understand the practical application of the electrical network theory through solving real world examples and problems. The Design Module will help students design real-life problems. These modules will be displayed after each section in the TechEBook for the user to relate his/her understanding with the outside world, which introduces the term me-applying and me-designing, as a comprehensive full experience for self or individualized education. The main emphasis of this paper is the PRM while the DM will be discussed in brief. A practical example of applying the PRM and DM features is discussed as part of a basic electrical engineering course currently given at UCF and results show improved student performances in learning materials in Electrical Circuits. In the future, such modules can be redesigned to become highly interactive with illustrated animations.

  17. Wireless Open-Circuit In-Plane Strain and Displacement Sensor Requiring No Electrical Connections

    Science.gov (United States)

    Woodard, Stanley E. (Inventor)

    2014-01-01

    A wireless in-plane strain and displacement sensor includes an electrical conductor fixedly coupled to a substrate subject to strain conditions. The electrical conductor is shaped between its ends for storage of an electric field and a magnetic field, and remains electrically unconnected to define an unconnected open-circuit having inductance and capacitance. In the presence of a time-varying magnetic field, the electrical conductor so-shaped resonates to generate harmonic electric and magnetic field responses. The sensor also includes at least one electrically unconnected electrode having an end and a free portion extending from the end thereof. The end of each electrode is fixedly coupled to the substrate and the free portion thereof remains unencumbered and spaced apart from a portion of the electrical conductor so-shaped. More specifically, at least some of the free portion is disposed at a location lying within the magnetic field response generated by the electrical conductor. A motion guidance structure is slidingly engaged with each electrode's free portion in order to maintain each free portion parallel to the electrical conductor so-shaped.

  18. Silicon photonic integrated circuits with electrically programmable non-volatile memory functions.

    Science.gov (United States)

    Song, J-F; Lim, A E-J; Luo, X-S; Fang, Q; Li, C; Jia, L X; Tu, X-G; Huang, Y; Zhou, H-F; Liow, T-Y; Lo, G-Q

    2016-09-19

    Conventional silicon photonic integrated circuits do not normally possess memory functions, which require on-chip power in order to maintain circuit states in tuned or field-configured switching routes. In this context, we present an electrically programmable add/drop microring resonator with a wavelength shift of 426 pm between the ON/OFF states. Electrical pulses are used to control the choice of the state. Our experimental results show a wavelength shift of 2.8 pm/ms and a light intensity variation of ~0.12 dB/ms for a fixed wavelength in the OFF state. Theoretically, our device can accommodate up to 65 states of multi-level memory functions. Such memory functions can be integrated into wavelength division mutiplexing (WDM) filters and applied to optical routers and computing architectures fulfilling large data downloading demands.

  19. Mechanically and electrically robust metal-mask design for organic CMOS circuits

    Science.gov (United States)

    Shintani, Michihiro; Qin, Zhaoxing; Kuribara, Kazunori; Ogasahara, Yasuhiro; Hiromoto, Masayuki; Sato, Takashi

    2018-04-01

    The design of metal masks for fabricating organic CMOS circuits requires the consideration of not only the electrical property of the circuits, but also the mechanical strength of the masks. In this paper, we propose a new design flow for metal masks that realizes coanalysis of the mechanical and electrical properties and enables design exploration considering the trade-off between the two properties. As a case study, we apply a “stitching technique” to the mask design of a ring oscillator and explore the best design. With this technique, mask patterns are divided into separate parts using multiple mask layers to improve the mechanical strength at the cost of high resistance of the vias. By a numerical experiment, the design trade-off of the stitching technique is quantitatively analyzed, and it is demonstrated that the proposed flow is useful for the exploration of the designs of metal masks.

  20. A general circuit model for spintronic devices under electric and magnetic fields

    KAUST Repository

    Alawein, Meshal

    2017-10-25

    In this work, we present a circuit model of diffusive spintronic devices capable of capturing the effects of both electric and magnetic fields. Starting from a modified version of the well-established drift-diffusion equations, we derive general equivalent circuit models of semiconducting/metallic nonmagnets and metallic ferromagnets. In contrast to other models that are based on steady-state transport equations which might also neglect certain effects such as thermal fluctuations, spin dissipation in the ferromagnets, and spin precession under magnetic fields, our model incorporates most of the important physics and is based on a time-dependent formulation. An application of our model is shown through simulations of a nonlocal spin-valve under the presence of a magnetic field, where we reproduce experimental results of electrical measurements that demonstrate the phenomena of spin precession and dephasing (“Hanle effect”).

  1. Simulation of Higher-Order Electrical Circuits with Stochastic Parameters via SDEs

    Directory of Open Access Journals (Sweden)

    BRANCIK, L.

    2013-02-01

    Full Text Available The paper deals with a technique for the simulation of higher-order electrical circuits with parameters varying randomly. The principle consists in the utilization of the theory of stochastic differential equations (SDE, namely the vector form of the ordinary SDEs. Random changes of both excitation voltage and some parameters of passive circuit elements are considered, and circuit responses are analyzed. The voltage and/or current responses are computed and represented in the form of the sample means accompanied by their confidence intervals to provide reliable estimates. The method is applied to analyze responses of the circuit models of optional orders, specially those consisting of a cascade connection of the RLGC networks. To develop the model equations the state-variable method is used, afterwards a corresponding vector SDE is formulated and a stochastic Euler numerical method applied. To verify the results the deterministic responses are also computed by the help of the PSpice simulator or the numerical inverse Laplace transforms (NILT procedure in MATLAB, while removing random terms from the circuit model.

  2. Numerical simulation for arc-plasma dynamics during contact opening process in electrical circuit-breakers

    International Nuclear Information System (INIS)

    Gupta, D N; Srinivas, D; Patil, G N; Kale, S S; Potnis, S B

    2010-01-01

    The high-energy, high-current thermal plasma that develops between electric contacts in a gas circuit-breaker during circuit interruption is an important phenomenon in the power transmission industry. The high temperature and pressure arc dissipates the tremendous amount of energy generated by the fault current. Simultaneously, this energy has to be transferred away from the contacts to build the dielectric strength level of the circuit-breaker. In order to interrupt the current, the arc must be weakened and finally extinguished. We model these phenomena by using a computer software code based on the solution of the unsteady Euler equations of gas dynamics. We consider the equations of fluid flows. These equations are solved numerically in complex circuit breaker geometries using a finite-volume method. The domain is initially filled with SF 6 gas. We begin our simulations from cold mode, where the fault current is not present (hence no arc). An axis-symmetric geometry of a 145 kV gas circuit-breaker is considered to study the pressure, density, and temperature profile during contact opening process.

  3. An Empirical Model for Estimating the Probability of Electrical Short Circuits from Tin Whiskers. Part 2

    Science.gov (United States)

    Courey, Karim; Wright, Clara; Asfour, Shihab; Onar, Arzu; Bayliss, Jon; Ludwig, Larry

    2009-01-01

    In this experiment, an empirical model to quantify the probability of occurrence of an electrical short circuit from tin whiskers as a function of voltage was developed. This empirical model can be used to improve existing risk simulation models. FIB and TEM images of a tin whisker confirm the rare polycrystalline structure on one of the three whiskers studied. FIB cross-section of the card guides verified that the tin finish was bright tin.

  4. Parameterization of electrical equivalent circuits for pem fuel cells; Parametrierung elektrischer Aequivalentschaltbilder von PEM Brennstoffzellen

    Energy Technology Data Exchange (ETDEWEB)

    Haubrock, J.

    2007-12-13

    Fuel cells are a very promising technology for energy conversion. For optimization purpose, useful simulation tools are needs. Simulation tools should simulate the static and dynamic electrical behaviour and the models should parameterized by measurment results which should be done easily. In this dissertation, a useful model for simulating a pem fuel cell is developed. the model should parametrizes by V-I curve measurment and by current step respond. The model based on electrical equivalent circuits and it is shown, that it is possible to simulate the dynamic behaviour of a pem fuel cell stack. The simulation results are compared by measurment results. (orig.)

  5. Laser cooling and optical detection of excitations in a LC electrical circuit

    DEFF Research Database (Denmark)

    Taylor, J. M.; Sørensen, Anders Søndberg; Marcus, Charles Masamed

    2011-01-01

    We explore a method for laser cooling and optical detection of excitations in a room temperature LC electrical circuit. Our approach uses a nanomechanical oscillator as a transducer between optical and electronic excitations. An experimentally feasible system with the oscillator capacitively...... coupled to the LC and at the same time interacting with light via an optomechanical force is shown to provide strong electromechanical coupling. Conditions for improved sensitivity and quantum limited readout of electrical signals with such an “optical loud speaker” are outlined....

  6. Development and Implementation of an Electric Circuits On-Line Course

    Directory of Open Access Journals (Sweden)

    Ahmed Hussain

    2009-02-01

    Full Text Available An electric circuit on-line course has been developed at KFUPM to support student centered learning. The course has been used in the first stage to supplement the class room face-to-face instruction. This paper describes the development stages of the on-line course and highlights its fundamental features that are not available in the traditional methods of instruction. The paper also includes the results of a survey conducted among students who have utilized the on-line material to supplement their traditional study of the electric circuits’ course. The results of the survey showed a general satisfaction with the course content and the instructional effectiveness.

  7. An Investigation of the Electrical Short Circuit Characteristics of Tin Whiskers

    Science.gov (United States)

    Courey, Karim J.

    2008-01-01

    Existing risk simulations make the assumption that when a free tin whisker has bridged two adjacent exposed electrical conductors, the result is an electrical short circuit. This conservative assumption is made because shorting is a random event that has a currently unknown probability associated with it. Due to contact resistance electrical shorts may not occur at lower voltage levels. In this experiment, we study the effect of varying voltage on the breakdown of the contact resistance which leads to a short circuit. From this data we can estimate the probability of an electrical short, as a function of voltage, given that a free tin whisker has bridged two adjacent exposed electrical conductors. Also, three tin whiskers grown from the same Space Shuttle Orbiter card guide used in the aforementioned experiment were cross-sectioned and studied using a focused ion beam (FIB). The rare polycrystalline structure seen in the FIB cross section was confirmed using transmission electron microscopy (TEM). The FIB was also used to cross section two card guides to facilitate the measurement of the grain size to determine that the tin plating on the card guides had a bright finish.

  8. A global model of thunderstorm electricity and the prediction of whistler duct formation

    International Nuclear Information System (INIS)

    Stansbery, E.K.

    1989-01-01

    A two-dimensional numerical model is created to calculate the electric field and current that flow from a thunderstorm source into the global electrical circuit. The model includes a hemisphere in which the thunderstorm is located, an equalization layer, and a passive magnetic conjugate hemisphere. To maintain the fair weather electric field, the output current from the thunderstorm is allowed to spread out in the ionosphere or flow along the magnetic field lines into the conjugate hemisphere. The vertical current is constant up to approximately 65 km, decays and is redirected horizontally in the ionosphere. Approximately half of the current that reaches the ionosphere flows along magnetic field lines into the conjugate hemisphere while the rest is spread out in the ionosphere and redirected to the fair weather portion of the storm hemisphere. Our results show that it is important to include a realistic model of the equalization layer to evaluate the role of thunderstorm charging of the global circuit. The mapping of thunderstorm electric fields at middle and subauroral latitudes into the magnetic equatorial plane is studied. The geomagnetic field lines are assumed to be dipolar above approximately 150 km. The horizontal electric field computed in the ionosphere by our model is of sufficient size and shape for the formation of electron density irregularities in the magnetosphere. The mechanism involves a localized convection of ionization tubes by ExB drift. It is shown that the horizontal range of the electric field disturbance in the ionosphere must be within approximately 160 km to produce density irregularities necessary for the formation of whistler ducts. Although the electric field strength at ionospheric heights depends sensitively on the conductivity profile, the results presented show that whistler duct formation is possible by thunderstorm generated electric fields.*

  9. On Global Electricity Usage of Communication Technology: Trends to 2030

    Directory of Open Access Journals (Sweden)

    Anders S. G. Andrae

    2015-04-01

    Full Text Available This work presents an estimation of the global electricity usage that can be ascribed to Communication Technology (CT between 2010 and 2030. The scope is three scenarios for use and production of consumer devices, communication networks and data centers. Three different scenarios, best, expected, and worst, are set up, which include annual numbers of sold devices, data traffic and electricity intensities/efficiencies. The most significant trend, regardless of scenario, is that the proportion of use-stage electricity by consumer devices will decrease and will be transferred to the networks and data centers. Still, it seems like wireless access networks will not be the main driver for electricity use. The analysis shows that for the worst-case scenario, CT could use as much as 51% of global electricity in 2030. This will happen if not enough improvement in electricity efficiency of wireless access networks and fixed access networks/data centers is possible. However, until 2030, globally-generated renewable electricity is likely to exceed the electricity demand of all networks and data centers. Nevertheless, the present investigation suggests, for the worst-case scenario, that CT electricity usage could contribute up to 23% of the globally released greenhouse gas emissions in 2030.

  10. Global electricity strategy: the twilight zone

    Energy Technology Data Exchange (ETDEWEB)

    Sack, J B

    1998-12-31

    Directions for the electric power industry in the wake of deregulation are discussed, with mention of independent power producers and distributed generation, and with analogies from the effect of deregulation on gas companies, telephone companies and airlines. The author considers that most electrical utilities are in poor shape to face change, because they have no adequately detailed cost breakdown. Management skills will be at a premium.

  11. Global electricity strategy: the twilight zone

    International Nuclear Information System (INIS)

    Sack, J.B.

    1997-01-01

    Directions for the electric power industry in the wake of deregulation are discussed, with mention of independent power producers and distributed generation, and with analogies from the effect of deregulation on gas companies, telephone companies and airlines. The author considers that most electrical utilities are in poor shape to face change, because they have no adequately detailed cost breakdown. Management skills will be at a premium

  12. [A case of the fatal injury by technical electricity from a mobile device (cell phone) connected to the circuit].

    Science.gov (United States)

    Rudenko, I A; Kil'dyushov, E M; Koludarova, E M; Morozov, V Yu; Fetisov, V A

    2015-01-01

    The authors report a case of the fatal injury by technical electricity from a mobile device (cell phone) attached to the circuit in a moist environment as a result of the unsafe handling of the gadget (when taking the bath).

  13. The Effect of Current-Limiting Reactors on the Tripping of Short Circuits in High-Voltage Electrical Equipment

    International Nuclear Information System (INIS)

    Volkov, M. S.; Gusev, Yu. P.; Monakov, Yu. V.; Cho, Gvan Chun

    2016-01-01

    The insertion of current-limiting reactors into electrical equipment operating at a voltage of 110 and 220 kV produces a change in the parameters of the transient recovery voltages at the contacts of the circuit breakers for disconnecting short circuits, which could be the reason for the increase in the duration of the short circuit, damage to the electrical equipment and losses in the power system. The results of mathematical modeling of the transients, caused by tripping of the short circuit in a reactive electric power transmission line are presented, and data are given on the negative effect of a current-limiting resistor on the rate of increase and peak value of the transient recovery voltages. Methods of ensuring the standard requirements imposed on the parameters of the transient recovery voltages when using current-limiting reactors in the high-voltage electrical equipment of power plants and substations are proposed and analyzed

  14. Circuit Mechanisms Governing Local vs. Global Motion Processing in Mouse Visual Cortex

    Directory of Open Access Journals (Sweden)

    Rune Rasmussen

    2017-12-01

    Full Text Available A withstanding question in neuroscience is how neural circuits encode representations and perceptions of the external world. A particularly well-defined visual computation is the representation of global object motion by pattern direction-selective (PDS cells from convergence of motion of local components represented by component direction-selective (CDS cells. However, how PDS and CDS cells develop their distinct response properties is still unresolved. The visual cortex of the mouse is an attractive model for experimentally solving this issue due to the large molecular and genetic toolbox available. Although mouse visual cortex lacks the highly ordered orientation columns of primates, it is organized in functional sub-networks and contains striate- and extrastriate areas like its primate counterparts. In this Perspective article, we provide an overview of the experimental and theoretical literature on global motion processing based on works in primates and mice. Lastly, we propose what types of experiments could illuminate what circuit mechanisms are governing cortical global visual motion processing. We propose that PDS cells in mouse visual cortex appear as the perfect arena for delineating and solving how individual sensory features extracted by neural circuits in peripheral brain areas are integrated to build our rich cohesive sensory experiences.

  15. [Work accidents and automatic circuit reclosers in the electricity sector: beyond the immediate causes].

    Science.gov (United States)

    Silva, Alessandro Jose Nunes da; Almeida, Ildeberto Muniz de; Vilela, Rodolfo Andrade de Gouveia; Mendes, Renata Wey Berti; Hurtado, Sandra Lorena Beltran

    2018-05-10

    The Brazilian electricity sector has recorded high work-related mortality rates that have been associated with outsourcing, used to cut costs. In order to decrease the power outage time for consumers, the industry adopted the automatic circuit recloser as the technical solution. The device has hazardous implications for maintenance workers. The aim of this study was to analyze the origins and consequences of work accidents in power systems with automatic circuit recloser, using the Accident Analysis and Prevention (AAP) model. The AAP model was used to investigate two work accidents, aimed to explore the events' organizational origins. Case 1 - when changing a deenergized secondary line, a worker received a shock from the energized primary cable (13.8kV). The system reclosed three times, causing severe injury to the worker (amputation of a lower limb). Case 2 - a fatal work accident occurred during installation of a new crosshead on a partially insulated energized line. The tip of a metal cross arm section strap touched the energized secondary line and electrocuted the maintenance operator. The circuit breaker component of the automatic circuit recloser failed. The analyses revealed how business management logic can participate in the root causes of work accidents through failures in maintenance management, outsourced workforce management, and especially safety management in systems with reclosers. Decisions to adopt automation to guarantee power distribution should not overlook the risks to workers in overhead power lines or fail to acknowledge the importance of ensuring safe conditions.

  16. Circuit Mechanisms Governing Local vs. Global Motion Processing in Mouse Visual Cortex

    DEFF Research Database (Denmark)

    Rasmussen, Rune; Yonehara, Keisuke

    2017-01-01

    components represented by component direction-selective (CDS) cells. However, how PDS and CDS cells develop their distinct response properties is still unresolved. The visual cortex of the mouse is an attractive model for experimentally solving this issue due to the large molecular and genetic toolbox...... literature on global motion processing based on works in primates and mice. Lastly, we propose what types of experiments could illuminate what circuit mechanisms are governing cortical global visual motion processing. We propose that PDS cells in mouse visual cortex appear as the perfect arena...

  17. Stretchable Transparent Electrode Arrays for Simultaneous Electrical and Optical Interrogation of Neural Circuits in Vivo.

    Science.gov (United States)

    Zhang, Jing; Liu, Xiaojun; Xu, Wenjing; Luo, Wenhan; Li, Ming; Chu, Fangbing; Xu, Lu; Cao, Anyuan; Guan, Jisong; Tang, Shiming; Duan, Xiaojie

    2018-04-09

    Recent developments of transparent electrode arrays provide a unique capability for simultaneous optical and electrical interrogation of neural circuits in the brain. However, none of these electrode arrays possess the stretchability highly desired for interfacing with mechanically active neural systems, such as the brain under injury, the spinal cord, and the peripheral nervous system (PNS). Here, we report a stretchable transparent electrode array from carbon nanotube (CNT) web-like thin films that retains excellent electrochemical performance and broad-band optical transparency under stretching and is highly durable under cyclic stretching deformation. We show that the CNT electrodes record well-defined neuronal response signals with negligible light-induced artifacts from cortical surfaces under optogenetic stimulation. Simultaneous two-photon calcium imaging through the transparent CNT electrodes from cortical surfaces of GCaMP-expressing mice with epilepsy shows individual activated neurons in brain regions from which the concurrent electrical recording is taken, thus providing complementary cellular information in addition to the high-temporal-resolution electrical recording. Notably, the studies on rats show that the CNT electrodes remain operational during and after brain contusion that involves the rapid deformation of both the electrode array and brain tissue. This enables real-time, continuous electrophysiological monitoring of cortical activity under traumatic brain injury. These results highlight the potential application of the stretchable transparent CNT electrode arrays in combining electrical and optical modalities to study neural circuits, especially under mechanically active conditions, which could potentially provide important new insights into the local circuit dynamics of the spinal cord and PNS as well as the mechanism underlying traumatic injuries of the nervous system.

  18. An Equivalent Electrical Circuit Model of Proton Exchange Membrane Fuel Cells Based on Mathematical Modelling

    Directory of Open Access Journals (Sweden)

    Dinh An Nguyen

    2012-07-01

    Full Text Available Many of the Proton Exchange Membrane Fuel Cell (PEMFC models proposed in the literature consist of mathematical equations. However, they are not adequately practical for simulating power systems. The proposed model takes into account phenomena such as activation polarization, ohmic polarization, double layer capacitance and mass transport effects present in a PEM fuel cell. Using electrical analogies and a mathematical modeling of PEMFC, the circuit model is established. To evaluate the effectiveness of the circuit model, its static and dynamic performances under load step changes are simulated and compared to the numerical results obtained by solving the mathematical model. Finally, the applicability of our model is demonstrated by simulating a practical system.

  19. Estimation of Operating Condition of Appliances Using Circuit Current Data on Electric Distribution Boards

    Science.gov (United States)

    Iwafune, Yumiko; Ogimoto, Kazuhiko; Yagita, Yoshie

    The Energy management systems (EMS) on demand sides are expected as a method to enhance the capability of supply and demand balancing of a power system under the anticipated penetration of renewable energy generation such as Photovoltaics (PV). Elucidation of energy consumption structure in a building is one of important elements for realization of EMS and contributes to the extraction of potential energy saving. In this paper, we propose the estimation method of operating condition of household appliances using circuit current data on an electric distribution board. Circuit current data are broken down by their shape using a self-organization map method and aggregated by appliance based on customers' information of appliance possessed. Proposed method is verified using residential energy consumption measurement survey data.

  20. Modeling of electrical and mesoscopic circuits at quantum nanoscale from heat momentum operator

    Science.gov (United States)

    El-Nabulsi, Rami Ahmad

    2018-04-01

    We develop a new method to study electrical circuits at quantum nanoscale by introducing a heat momentum operator which reproduces quantum effects similar to those obtained in Suykens's nonlocal-in-time kinetic energy approach for the case of reversible motion. The series expansion of the heat momentum operator is similar to the momentum operator obtained in the framework of minimal length phenomenologies characterized by the deformation of Heisenberg algebra. The quantization of both LC and mesoscopic circuits revealed a number of motivating features like the emergence of a generalized uncertainty relation and a minimal charge similar to those obtained in the framework of minimal length theories. Additional features were obtained and discussed accordingly.

  1. Factors influencing the renal arterial Doppler waveform: a simulation study using an electrical circuit model (secondary publication)

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Chang Kyu [Dept. of Radiology, SMG-SNU Boramae Medical Center, Seoul National University College of Medicine, Seoul (Korea, Republic of); Han, Bong Soo [Dept. of Radiological Science, College of Health Science, Yonsei University, Wonju (Korea, Republic of); Kim, Seung Hyup [Dept. of Radiology, Institute of Radiation Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul (Korea, Republic of)

    2016-01-15

    The goal of this study was to evaluate the effect of vascular compliance, resistance, and pulse rate on the resistive index (RI) by using an electrical circuit model to simulate renal blood flow. In order to analyze the renal arterial Doppler waveform, we modeled the renal blood-flow circuit with an equivalent simple electrical circuit containing resistance, inductance, and capacitance. The relationships among the impedance, resistance, and compliance of the circuit were derived from well-known equations, including Kirchhoff’s current law for alternating current circuits. Simulated velocity-time profiles for pulsatile flow were generated using Mathematica (Wolfram Research) and the influence of resistance, compliance, and pulse rate on waveforms and the RI was evaluated. Resistance and compliance were found to alter the waveforms independently. The impedance of the circuit increased with increasing proximal compliance, proximal resistance, and distal resistance. The impedance decreased with increasing distal compliance. The RI of the circuit decreased with increasing proximal compliance and resistance. The RI increased with increasing distal compliance and resistance. No positive correlation between impedance and the RI was found. Pulse rate was found to be an extrinsic factor that also influenced the RI. This simulation study using an electrical circuit model led to a better understanding of the renal arterial Doppler waveform and the RI, which may be useful for interpreting Doppler findings in various clinical settings.

  2. Factors influencing the renal arterial Doppler waveform: a simulation study using an electrical circuit model (secondary publication)

    International Nuclear Information System (INIS)

    Sung, Chang Kyu; Han, Bong Soo; Kim, Seung Hyup

    2016-01-01

    The goal of this study was to evaluate the effect of vascular compliance, resistance, and pulse rate on the resistive index (RI) by using an electrical circuit model to simulate renal blood flow. In order to analyze the renal arterial Doppler waveform, we modeled the renal blood-flow circuit with an equivalent simple electrical circuit containing resistance, inductance, and capacitance. The relationships among the impedance, resistance, and compliance of the circuit were derived from well-known equations, including Kirchhoff’s current law for alternating current circuits. Simulated velocity-time profiles for pulsatile flow were generated using Mathematica (Wolfram Research) and the influence of resistance, compliance, and pulse rate on waveforms and the RI was evaluated. Resistance and compliance were found to alter the waveforms independently. The impedance of the circuit increased with increasing proximal compliance, proximal resistance, and distal resistance. The impedance decreased with increasing distal compliance. The RI of the circuit decreased with increasing proximal compliance and resistance. The RI increased with increasing distal compliance and resistance. No positive correlation between impedance and the RI was found. Pulse rate was found to be an extrinsic factor that also influenced the RI. This simulation study using an electrical circuit model led to a better understanding of the renal arterial Doppler waveform and the RI, which may be useful for interpreting Doppler findings in various clinical settings

  3. 76 FR 19174 - In the Matter of Circuit Systems, Inc., Global Energy Group, Inc., Integrated Medical Resources...

    Science.gov (United States)

    2011-04-06

    ... SECURITIES AND EXCHANGE COMMISSION File No. 500-1 In the Matter of Circuit Systems, Inc., Global Energy Group, Inc., Integrated Medical Resources, Inc., iNTELEFILM Corp., and Lot$off Corp.; Order of... lack of current and accurate information concerning the securities of Circuit Systems, Inc. because it...

  4. Current, voltage and temperature distribution modeling of light-emitting diodes based on electrical and thermal circuit analysis

    International Nuclear Information System (INIS)

    Yun, J; Shim, J-I; Shin, D-S

    2013-01-01

    We demonstrate a modeling method based on the three-dimensional electrical and thermal circuit analysis to extract current, voltage and temperature distributions of light-emitting diodes (LEDs). In our model, the electrical circuit analysis is performed first to extract the current and voltage distributions in the LED. Utilizing the result obtained from the electrical circuit analysis as distributed heat sources, the thermal circuit is set up by using the duality between Fourier's law and Ohm's law. From the analysis of the thermal circuit, the temperature distribution at each epitaxial film is successfully obtained. Comparisons of experimental and simulation results are made by employing an InGaN/GaN multiple-quantum-well blue LED. Validity of the electrical circuit analysis is confirmed by comparing the light distribution at the surface. Since the temperature distribution at each epitaxial film cannot be obtained experimentally, the apparent temperature distribution is compared at the surface of the LED chip. Also, experimentally obtained average junction temperature is compared with the value calculated from the modeling, yielding a very good agreement. The analysis method based on the circuit modeling has an advantage of taking distributed heat sources as inputs, which is essential for high-power devices with significant self-heating. (paper)

  5. Design of Strain-Compensated Epitaxial Layers Using an Electrical Circuit Model

    Science.gov (United States)

    Kujofsa, Tedi; Ayers, John E.

    2017-12-01

    The design of heterostructures that exhibit desired strain characteristics is critical for the realization of semiconductor devices with improved performance and reliability. The control of strain and dislocation dynamics requires an understanding of the relaxation processes associated with mismatched epitaxy, and the starting point for this analysis is the equilibrium strain profile, because the difference between the actual strain and the equilibrium value determines the driving force for dislocation glide and relaxation. Previously, we developed an electrical circuit model approach for the equilibrium analysis of semiconductor heterostructures, in which an epitaxial layer may be represented by a stack of subcircuits, each of which involves an independent current source, a resistor, an independent voltage source, and an ideal diode. In this work, we have applied the electrical circuit model to study the strain compensation mechanism and show that, for a given compositionally uniform device layer with fixed mismatch and layer thickness, a buffer layer may be designed (in terms of thickness and mismatch) to tailor the strain in the device layer. A special case is that in which the device layer will exhibit zero residual strain in equilibrium (complete strain compensation). In addition, the application of the electrical circuit analogy enables the determination of exact expressions for the residual strain characteristics of both the buffer and device layers in the general case where the device layer may exhibit partial strain compensation. On the basis of this framework, it is possible to develop design equations for the tailoring of the strain in a device layer grown on a uniform composition buffer.

  6. Variations in the electrical short-circuit current decay for recombination lifetime and velocity measurements

    Science.gov (United States)

    Jung, Tae-Won; Lindholm, Fredrik A.; Neugroschel, Arnost

    1987-01-01

    An improved measurement system for electrical short-circuit current decay is presented that extends applicability of the method to silicon solar cells having an effective lifetime as low as 1 microsec. The system uses metal/oxide/semiconductor transistors as voltage-controlled switches. Advances in theory developed here increase precision and sensitivity in the determination of the minority-carrier recombination lifetime and recombination velocity. A variation of the method, which exploits measurements made on related back-surface field and back-ohmic contact devices, further improves precision and sensitivity. The improvements are illustrated by application to 15 different silicon solar cells.

  7. Web-based eTutor for learningn electrical circuit analysis

    OpenAIRE

    Debono, Jason; Muscat, Adrian; Porter, Chris; Connections

    2018-01-01

    This paper discusses a web-based eTutor for learning electrical circuit analysis. The eTutor system components, mainly the user-interface and the assessment model, are described. The system architecture developed provides a framework to support interactive sessions between the human and the machine for the case when the human is a student and the machine a tutor and also for the case when the roles of the human and the machine are swapped. To motivate the usefulness of the data...

  8. MoREK: The learning media to improve students understanding about electrical circuit in informatics

    Science.gov (United States)

    Indrianto; Nur Indah Susanti, Meilia; Arianto, Rakhmat

    2018-03-01

    The needs for labor in the world is already increasing especially in Indonesia. According to the World Bank, Indonesia is a country that ranks 9th in the world’s largest economic growth. To meet that needs, Indonesia needs 55 million workers who are experts in the field of electricity. Therefore, it takes a lot of human resources and has been equipped with knowledge and expertise in the field of electricity. To be able to meet these needs, it takes a better method of learning to increase knowledge and expertise in the field of electricity since college, especially in the field of informatics. Prototype of Electrical Module (The MoREK) requires a Prototype method for the Practicum Module to be created as desired. This method is often used in the real world or it could be said Prototype method is part of the product that expresses the logic and physical external interface that is displayed. For data retrieval is used Pre-experimental method where students will be given pre-test and post-test. The Design of Electrical Module has a purpose to improve the students understanding of Electric Circuit Engineering Courses with the creation of The MoREK so that students are more competent to the course and can meet the needs of manpower or Human Resources (SDM) in the field of electricity. By using The Morek, the score of student learning outcomes increased by 7.8% and informatics students who conduct research in the field of electricity increased to 21%.

  9. Bidirectional global spontaneous network activity precedes the canonical unidirectional circuit organization in the developing hippocampus.

    Science.gov (United States)

    Shi, Yulin; Ikrar, Taruna; Olivas, Nicholas D; Xu, Xiangmin

    2014-06-15

    Spontaneous network activity is believed to sculpt developing neural circuits. Spontaneous giant depolarizing potentials (GDPs) were first identified with single-cell recordings from rat CA3 pyramidal neurons, but here we identify and characterize a large-scale spontaneous network activity we term global network activation (GNA) in the developing mouse hippocampal slices, which is measured macroscopically by fast voltage-sensitive dye imaging. The initiation and propagation of GNA in the mouse is largely GABA-independent and dominated by glutamatergic transmission via AMPA receptors. Despite the fact that signal propagation in the adult hippocampus is strongly unidirectional through the canonical trisynaptic circuit (dentate gyrus [DG] to CA3 to CA1), spontaneous GNA in the developing hippocampus originates in distal CA3 and propagates both forward to CA1 and backward to DG. Photostimulation-evoked GNA also shows prominent backward propagation in the developing hippocampus from CA3 to DG. Mouse GNA is strongly correlated to electrophysiological recordings of highly localized single-cell and local field potential events. Photostimulation mapping of neural circuitry demonstrates that the enhancement of local circuit connections to excitatory pyramidal neurons occurs over the same time course as GNA and reveals the underlying pathways accounting for GNA backward propagation from CA3 to DG. The disappearance of GNA coincides with a transition to the adult-like unidirectional circuit organization at about 2 weeks of age. Taken together, our findings strongly suggest a critical link between GNA activity and maturation of functional circuit connections in the developing hippocampus. Copyright © 2013 Wiley Periodicals, Inc.

  10. Rocket measurements within a polar cap arc: Plasma, particle, and electric circuit parameters

    International Nuclear Information System (INIS)

    Weber, E.J.; Ballenthin, J.O.; Basu, S.; Carlson, H.C.; Hardy, D.A.; Maynard, N.C.; Smiddy, M.; Kelley, M.C.; Fleischman, J.R.; Sheehan, R.E.; Pfaff, R.F.; Rodriguez, P.

    1989-01-01

    An instrumented rocket payload was launched into a polar cap F layer aurora to investigate the energetic particle, plasma, and electric circuit parameters of a Sun-aligned arc. On-board instruments measured energetic electron flux, ion composition and density fluctuations, electron density and temperature, electron density fluctuations, and ac and dc electric fields. Real-time all-sky imaging photometer measurements of the location and motion of the aurora, were used to determine the proper geophysical situation for launch. Comparison of the in situ measurements with remote optical measurements shows that the arc was produced by fluxes of low-energy (< 1 keV) electrons. Field-aligned potentials in the arc inferred from the electron spectra had a maximum value of approximately 300 V, and from the spectral shape a parent population of preaccelerated electrons characteristic of the boundary plasma sheet or magnetosheath was inferred. Electric field components along and across the arc show sunward flow within the arc and duskward drift of the arc consistent with the drift direction and speed determined from optical imaging. Thus this arc is drifting duskward under the influence of the convection electric field. Three possible explanations for this (field-aligned currents, chemistry, and transport) are considered. Finally, ionospheric irregularity and electric field fluctuations indicate two different generation mechanisms on the dawnside and duskside of the arc. On the duskside, parameters are suggestive of an interchange process, while on the dawnside, fluctuation parameters are consistent with a velocity shear instability

  11. Mode of the short circuit in the direct current electric traction network with different feed charts of fyder area

    Directory of Open Access Journals (Sweden)

    P. Mihalichenko

    2012-12-01

    Full Text Available In the article the results of mathematical design of the system of electric traction of direct current are represented in the mode of short circuit and different feed charts of fyder area: two-sided; one-sided. Comparison of transitional electric sizes which characterize electromagnetic processes during these malfunctions is analysed and executed.

  12. Unexpected ICD pulse generator failure due to electronic circuit damage caused by electrical overstress.

    Science.gov (United States)

    Hauser, R G; Hayes, D L; Almquist, A K; Epstein, A E; Parsonnet, V; Tyers, G F; Vlay, S C; Schoenfeld, M H

    2001-07-01

    Because it is a lifesaving device, the unexpected failure of an ICD can be catastrophic. We report ICD electronic circuit failure due to electrical overstress damage (EOS) to the high voltage hybird circuit and other electronic components in a series of ICD pulse generator models. Data were obtained from the Multicenter Registry of Pacemaker and ICD Pacemaker and Lead Failures, and from the manufactures' adverse event reports, that were in the FDA's Manufacturer and User Facility Device Experience (MAUDE) database. Of 16 nonbattery Guidant/CPI ICD pulse generator failures reported to the registry, 6 (38%) have been confirmed by the manufacturer to be EOS related, and Guidant/CPI has reported 273 such failures to the FDA as of 12/29/00. The signs of failure included loss of telemetry and inability to deliver therapy, and some patients have experienced serious adverse events. Hybrid circuit damage may have occurred during capacitor charging or reform, and the majority appears to have happened during normal ICD function. While the incidence of this problem is unknown, a management strategy should be adopted that includes routine follow-up every 3 months and device evaluation after a shock or exposure to external defibrillation or electrosurgical devices. This study suggests that additional data are needed to determine the incidence of this problem, and that our present methods for monitoring the performance of ICD's following market release are inadequate.

  13. A study on the equivalent electric circuit simulation model of DBD streamer and glow alternate discharge

    International Nuclear Information System (INIS)

    Yao, J; Zhang, Z T; Xu, S J; Yu, Q X; Yu, Z; Zhao, J S

    2013-01-01

    This paper presents a dynamic simulating model of the dielectric barrier discharge (DBD), structured as an equivalent electric circuit of the streamer and glow discharge generated alternately in DBD. The main parameters of DBD have been established by means of analysing the structural characteristics of a single discharge cell. An electrical comprehensive Simulink /MATLAB model was developed in order to reveal the interaction of the adjacent two discharge cell. A series of simulations was carried out in order to estimate the key structural parameters that affect the alternate streamer and glow discharge mode. The comparison results of experimental and simulate indicate that there exists a close similarity of the current waveforms graphic. Therefore, we can grasp a deep understanding mechanism of the dielectric barrier discharge and optimize the plasma reactor.

  14. Equivalence between classical and quantum dynamics. Neutral kaons and electric circuits

    International Nuclear Information System (INIS)

    Caruso, M.; Fanchiotti, H.; Canal, C.A. Garcia

    2011-01-01

    An equivalence between the Schroedinger dynamics of a quantum system with a finite number of basis states and a classical dynamics is presented. The equivalence is an isomorphism that connects in univocal way both dynamical systems. We treat the particular case of neutral kaons and found a class of electric networks uniquely related to the kaon system finding the complete map between the matrix elements of the effective Hamiltonian of kaons and those elements of the classical dynamics of the networks. As a consequence, the relevant ε parameter that measures CP violation in the kaon system is completely determined in terms of network parameters. - Highlights: → We provide a formal equivalence between classical and quantum dynamics. → We make use of the decomplexification concept. → Neutral kaon systems can be represented by electric circuits. → CP symmetry violation can be taken into account by non-reciprocity. → Non-reciprocity is represented by gyrators.

  15. New electric technologies to reduce global warming impacts

    International Nuclear Information System (INIS)

    Courtright, H.A.

    1994-01-01

    Advanced electric technologies hold significant potential to reduce global warming impact through reduction of primary fuel needed to power end-use applications. These reductions can occur in two forms: (1) reduced kilowatt-hour usage and power plant emissions through efficiency improvements and technological enhancements of existing electrically-driven applications; (2) the development of new electric technologies to replace traditional fossil-fuel driven applications which can result in less overall primary energy consumption and lower overall emissions. Numerous new electric technologies are presently being developed by the Electric Power Research Institute. The technologies reviewed in this paper include: Microwave Fabric Dryer, Advanced Heat Pumps, Heat Pump Water Heater, Infrared Sand Reclaimer, Freeze Concentration, Membrane Water Recovery, Microwave Petrochemical Production, Infrared Drying, and Electric Vehicles. Full commercialization of these technologies can result in significant energy savings and CO 2 reductions, in addition to improving the competitiveness of businesses using these technologies

  16. Relative Contributions of Electrified Shower Clouds and Thunderstorms to the Global Circuit: Can 10 Years of TRMM Data Help Solve an Old Puzzle? (Invited)

    Science.gov (United States)

    Zipser, E. J.; Liu, C.; Williams, E.; Burns, G. B.

    2010-12-01

    The long-standing mainstay of support for C.T.R. Wilson’s global circuit hypothesis is the similarity between the diurnal variation of thunderstorm days in universal time, and the Carnegie curve of electrical potential gradient (Whipple, 1929). This rough agreement has sustained the widespread view that thunderstorms are the “batteries” for the global electrical circuit. This study utilizes 10 years of Tropical Rainfall Measuring Mission (TRMM) observations to quantify the global occurrence of thunderstorms with much better accuracy and validate the comparison by Whipple 80 years ago. The results support Wilson’s (1920) original ideas that both thunderstorms and electrified shower clouds contribute to the DC global circuit by virtue of negative charge carried downward by precipitation. First, the precipitation features (PFs) are defined by grouping the pixels with rain using 10 years of TRMM observations. Thunderstorms are identified from these PFs with lightning flashes observed by the Lightning Imaging Sensor. PFs without lightning flashes but with the 30 dBZ radar echo top temperature below -10oC over land and -17 oC over ocean are selected as possibly electrified shower clouds. The universal diurnal variation of rainfall, raining area from the thunderstorms and possibly electrified shower clouds in different seasons are derived and compared with the diurnal variations of the electric field observed at Vostok, Antarctica. The result shows a substantially better match from the updated diurnal variations of the thunderstorm area to the Carnegie curve than Whipple showed. One reason for the improvement is that the TRMM data are able to distinguish the relatively larger contributions from electrified shower clouds than thunderstorms over tropical oceans and over the Amazon. Potential further refinements to the current algorithm defining electrified convective cells are discussed.

  17. NRC Information No. 90-41: Potential failure of General Electric Magne-Blast circuit breakers and AK circuit breakers

    International Nuclear Information System (INIS)

    Rossi, C.E.

    1992-01-01

    This information notice is intended to alert addressees to potential safety concerns that may result from failures of GE vertical lift (AM) and horizontal draw-out (AMH) Magne-Blast circuit breakers utilizing ML-13 operating mechanisms to open or close them and AK circuit breakers. The particular breaker failures reported herein were caused by operating problems with prop springs, snap rings and lubricating grease. GE Nuclear Energy has informed the NRC that it is aware of these problems and that GE routinely checks and corrects them if the circuit breakers are serviced at one of the four GE nuclear service centers in the US. However, the NRC is aware that some utilities may have their circuit breakers repaired or serviced at facilities other than the four GE nuclear service centers

  18. Enhancing Communication Skills of Pre-service Physics Teacher through HOT Lab Related to Electric Circuit

    Science.gov (United States)

    Malik, A.; Setiawan, A.; Suhandi, A.; Permanasari, A.; Dirgantara, Y.; Yuniarti, H.; Sapriadil, S.; Hermita, N.

    2018-01-01

    This study aimed to investigate the improvement to pre-service teacher’s communication skills through Higher Order Thinking Laboratory (HOT Lab) on electric circuit topic. This research used the quasi-experiment method with pretest-posttest control group design. Research subjects were 60 students of Physics Education in UIN Sunan Gunung Djati Bandung. The sample was chosen by random sampling technique. Students’ communication skill data collected using a communication skills test instruments-essays form and observations sheets. The results showed that pre-service teacher communication skills using HOT Lab were higher than verification lab. Student’s communication skills in groups using HOT Lab were not influenced by gender. Communication skills could increase due to HOT Lab based on problems solving that can develop communication through hands-on activities. Therefore, the conclusion of this research shows the application of HOT Lab is more effective than the verification lab to improve communication skills of pre-service teachers in electric circuit topic and gender is not related to a person’s communication skills.

  19. A new method for electric impedance imaging using an eddy current with a tetrapolar circuit.

    Science.gov (United States)

    Ahsan-Ul-Ambia; Toda, Shogo; Takemae, Tadashi; Kosugi, Yukio; Hongo, Minoru

    2009-02-01

    A new contactless technique for electrical impedance imaging, using an eddy current managed along with the tetrapolar circuit method, is proposed. The eddy current produced by a magnetic field is superimposed on a constant current that is normally used in the tetrapolar circuit method, and thus is used to control the current distribution in the body. By changing the current distribution, a set of voltage differences is measured with a pair of electrodes. This set of voltage differences is used in the image reconstruction of the resistivity distribution. The least square error minimization method is used in the reconstruction algorithm. The principle of this method is explained theoretically. A backprojection algorithm was used to get 2-D images. Based on this principle, a measurement system was developed and model experiments were conducted with a saline-filled phantom. The estimated shape of each model in the reconstructed image was similar to that of the corresponding model. From the results of these experiments, it is confirmed that the proposed method is applicable to the realization of electrical conductivity imaging.

  20. Global EV Outlook: Understanding the Electric Vehicle Landscape to 2020

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-06-01

    The Global EV Outlook represents the collective efforts of two years of primary data gathering and analysis from the Electric Vehicles Initiative (EVI) and IEA. Key takeaways and insights include landscape analysis of electric vehicle (EV) stock/sales and charging station deployment. Existing policy initiatives are delineated and future opportunities highlighted in an ''Opportunity Matrix: Pathways to 2020''. Together EVI countries accounted for more than 90% of world EV stock at the end of 2012. Strong government support in EVI countries on both the supply and demand sides are contributing to rising market penetration. 12 out of 15 EVI countries offer financial support for vehicle purchases, and most employ a mix of financial and non-financial incentives (such as access to restricted highway lanes) to help drive adoption. The Global EV Outlook is a unique and data-rich overview of the state of electric vehicles today, and offers an understanding of the electric vehicle landscape to 2020.

  1. An improved electrical and thermal model of a microbolometer for electronic circuit simulation

    Science.gov (United States)

    Würfel, D.; Vogt, H.

    2012-09-01

    The need for uncooled infrared focal plane arrays (IRFPA) for imaging systems has increased since the beginning of the nineties. Examples for the application of IRFPAs are thermography, pedestrian detection for automotives, fire fighting, and infrared spectroscopy. It is very important to have a correct electro-optical model for the simulation of the microbolometer during the development of the readout integrated circuit (ROIC) used for IRFPAs. The microbolometer as the sensing element absorbs infrared radiation which leads to a change of its temperature due to a very good thermal insulation. In conjunction with a high temperature coefficient of resistance (TCR) of the sensing material (typical vanadium oxide or amorphous silicon) this temperature change results in a change of the electrical resistance. During readout, electrical power is dissipated in the microbolometer, which increases the temperature continuously. The standard model for the electro-optical simulation of a microbolometer includes the radiation emitted by an observed blackbody, radiation emitted by the substrate, radiation emitted by the microbolometer itself to the surrounding, a heat loss through the legs which connect the microbolometer electrically and mechanically to the substrate, and the electrical power dissipation during readout of the microbolometer (Wood, 1997). The improved model presented in this paper takes a closer look on additional radiation effects in a real IR camera system, for example the radiation emitted by the casing and the lens. The proposed model will consider that some parts of the radiation that is reflected from the casing and the substrate is also absorbed by the microbolometer. Finally, the proposed model will include that some fraction of the radiation is transmitted through the microbolometer at first and then absorbed after the reflection at the surface of the substrate. Compared to the standard model temperature and resistance of the microbolometer can be

  2. Modeling the dynamic and thermodynamic operation of Stirling engines by means of an equivalent electrical circuit

    International Nuclear Information System (INIS)

    Cascella, Franco; Sorin, Mikhail; Formosa, Fabien; Teyssedou, Alberto

    2017-01-01

    Highlights: • A model based on the electrical analogy theory has been developed to predict the operation of a Stirling engine. • The models takes into account the continuity, the momentum and the energy conservation equations. • The model predicts the operating conditions of the RE100 Free piston Stirling engine. • The model is sensible to the modeling of the effects of the machine load. - Abstract: The Stirling engines are inherently efficient; their thermodynamic cycles reach the Carnot efficiency. These technologies are suitable to operate under any low temperature difference between the hot and the cold sources. For these reasons, these engines can be considered as reliable power conversion systems to promote the conversion of low-grade waste heat generated by industrial plants. The need of a model to predict the behavior of these engines is of primary importance. Nevertheless, a great difficulty is encountered in developing such a model since it is not simple to take into account coupled thermodynamic and dynamic effects. This is the main reason why several models make use of electrical analogies to describe Stirling engines (in particular, free-piston machines): by assuming the pressure equivalent to a voltage and the flow rate to an electrical current, a coupled dynamic-thermodynamic analysis of the engine can be performed. In this paper, an electrical circuit whose behavior is equivalent to that of the engine is derived from the electrical analogy theory. To this aim, we propose an electrical analogy model based on the three conservation laws (mass, momentum and energy). Since limited experimental information is available in the open literature, the results obtained with the proposed model are compared with the experimental data collected at the NASA Lewis Research center for a free-piston Stirling engine i.e., the RE-1000 engine.

  3. Method for heating of the primary circuit of WWER electric power units at cold start-up

    International Nuclear Information System (INIS)

    Ivanov, I.N.; Dimitrov, B.D.; Korkinova, M.I.

    1982-01-01

    The method increases the heating rate and shorten the start-up time of the electric power units. It comprises a primary stopping of the reactor core heating and provides a forced circulation of the heat-carrier through the circulation cycles of the primary circuit. The thermal energy is supplied in one or several steam generators in the secondary circuit of an NPP operating unit. 1 cl., 3 figs

  4. A comparative mathematical analysis of RL and RC electrical circuits via Atangana-Baleanu and Caputo-Fabrizio fractional derivatives

    Science.gov (United States)

    Abro, Kashif Ali; Memon, Anwar Ahmed; Uqaili, Muhammad Aslam

    2018-03-01

    This research article is analyzed for the comparative study of RL and RC electrical circuits by employing newly presented Atangana-Baleanu and Caputo-Fabrizio fractional derivatives. The governing ordinary differential equations of RL and RC electrical circuits have been fractionalized in terms of fractional operators in the range of 0 ≤ ξ ≤ 1 and 0 ≤ η ≤ 1. The analytic solutions of fractional differential equations for RL and RC electrical circuits have been solved by using the Laplace transform with its inversions. General solutions have been investigated for periodic and exponential sources by implementing the Atangana-Baleanu and Caputo-Fabrizio fractional operators separately. The investigated solutions have been expressed in terms of simple elementary functions with convolution product. On the basis of newly fractional derivatives with and without singular kernel, the voltage and current have interesting behavior with several similarities and differences for the periodic and exponential sources.

  5. An Empirical Model for Estimating the Probability of Electrical Short Circuits from Tin Whiskers-Part I

    Science.gov (United States)

    Courey, Karim; Wright, Clara; Asfour, Shihab; Bayliss, Jon; Ludwig, Larry

    2008-01-01

    Existing risk simulations make the assumption that when a free tin whisker has bridged two adjacent exposed electrical conductors, the result is an electrical short circuit. This conservative assumption is made because shorting is a random event that has a currently unknown probability associated with it. Due to contact resistance, electrical shorts may not occur at lower voltage levels. In this experiment, we study the effect of varying voltage on the breakdown of the contact resistance which leads to a short circuit. From this data, we can estimate the probability of an electrical short, as a function of voltage, given that a free tin whisker has bridged two adjacent exposed electrical conductors. In addition, three tin whiskers grown from the same Space Shuttle Orbiter card guide used in the aforementioned experiment were cross sectioned and studied using a focused ion beam (FIB).

  6. Circuit modeling of the electrical impedance: part III. Disuse following bone fracture

    International Nuclear Information System (INIS)

    Shiffman, C A

    2013-01-01

    Multifrequency measurements of the electrical impedance of muscle have been extended to the study of disuse following bone fracture, and analyzed using the five-element circuit model used earlier in the study of the effects of disease. Eighteen subjects recovering from simple fractures on upper or lower limbs were examined (ten males, eight females, aged 18–66). Muscles on uninjured contralateral limbs were used as comparison standards, and results are presented in terms of the ratios p(injured)/p(uninjured), where p stands for the circuit parameter r 1 , r 2 , r 3 , 1/c 1 or 1/c 2 . These are strikingly similar to the diseased-to-healthy ratios for patients with neuromuscular disease, reported in part I of this series. In particular, r 1 is virtually unaffected and the ratios for r 2 , r 3 , 1/c 1 and 1/c 2 can be as large as in serious disease. Furthermore, the same pattern of relationships between the parameters is found, suggesting that there is a common underlying mechanism for the impedance changes. Atrophy and fibrosis are examined as candidates for that mechanism, but it is argued that their effects are too small to explain the observed changes. Fundamental considerations aside, the sensitivity, reproducibility and technical simplicity of the technique recommend its use for in-flight assessments of muscles during orbital or interplanetary missions. (paper)

  7. Automatic analysis at the commissioning of the LHC superconducting electrical circuits

    International Nuclear Information System (INIS)

    Reymond, H.; Andreassen, O.O.; Charrondiere, C.; Rijllart, A.; Zerlauth, M.

    2012-01-01

    Since the beginning of 2010 the LHC has been operating in a routinely manner, starting with a commissioning phase and then an operation for physics phase. The commissioning of the superconducting electrical circuits requires rigorous test procedures before entering into operation. To maximize the beam operation time of the LHC, these tests should be done as fast as procedures allow. A full commissioning need 12000 tests and is required after circuits have been warmed above liquid nitrogen temperature. Below this temperature, after an end of year break of two months, commissioning needs about 6000 tests. As the manual analysis of the tests takes a major part of the commissioning time, we automated existing analysis tools. We present here how these LabVIEW TM applications were automated, the evaluation of the gain in commissioning time and reduction of experts on night shift observed during the LHC hardware commissioning campaign of 2011 compared to 2010. We end with an outlook at what can be further optimized. (authors)

  8. Automatic Analysis at the Commissioning of the LHC Superconducting Electrical Circuits

    CERN Document Server

    Reymond, H; Charrondiere, C; Rijllart, A; Zerlauth, M

    2011-01-01

    Since the beginning of 2010 the LHC has been operating in a routinely manner, starting with a commissioning phase and then an operation for physics phase. The commissioning of the superconducting electrical circuits requires rigorous test procedures before entering into operation. To maximize the beam operation time of the LHC, these tests should be done as fast as procedures allow. A full commissioning need 12000 tests and is required after circuits have been warmed above liquid nitrogen temperature. Below this temperature, after an end of year break of two months, commissioning needs about 6000 tests. As the manual analysis of the tests takes a major part of the commissioning time, we automated existing analysis tools. We present here how these LabVIEW™ applications were automated, the evaluation of the gain in commissioning time and reduction of experts on night shift observed during the LHC hardware commissioning campaign of 2011 compared to 2010. We end with an outlook at what can be further optimized.

  9. Investigating the role of socially mediated metacognition during collaborative troubleshooting of electric circuits

    Science.gov (United States)

    Van De Bogart, Kevin L.; Dounas-Frazer, Dimitri R.; Lewandowski, H. J.; Stetzer, MacKenzie R.

    2017-12-01

    Developing students' ability to troubleshoot is an important learning outcome for many undergraduate physics lab courses, especially electronics courses. In other work, metacognition has been identified as an important feature of troubleshooting. However, that work has focused primarily on individual students' metacognitive processes or troubleshooting abilities. In contrast, electronics courses often require students to work in pairs, and hence students' in-class experiences likely have significant social dimensions that are not well understood. In this work, we use an existing framework for socially mediated metacognition to analyze audiovisual data from think-aloud activities in which eight pairs of students from two institutions attempted to diagnose and repair a malfunctioning electric circuit. In doing so, we provide insight into some of the social metacognitive dynamics that arise during collaborative troubleshooting. We find that students engaged in socially mediated metacognition at multiple key transitions during the troubleshooting process. Reciprocated metacognitive dialogue arose when students were collectively strategizing about which measurements to perform, or reaching a shared understanding of the circuit's behavior. Our research demonstrates the value of the framework of socially mediated metacognition in providing insight into the nature of collaborative student troubleshooting in the context of electronics. As such, this framework may be a useful resource for future efforts to examine and support the development of student troubleshooting skills in other upper-division laboratory courses.

  10. Quantifying Demyelination in NK venom treated nerve using its electric circuit model.

    Science.gov (United States)

    Das, H K; Das, D; Doley, R; Sahu, P P

    2016-03-02

    Reduction of myelin in peripheral nerve causes critical demyelinating diseases such as chronic inflammatory demyelinating polyneuropathy, Guillain-Barre syndrome, etc. Clinical monitoring of these diseases requires rapid and non-invasive quantification of demyelination. Here we have developed formulation of nerve conduction velocity (NCV) in terms of demyelination considering electric circuit model of a nerve having bundle of axons for its quantification from NCV measurements. This approach has been validated and demonstrated with toad nerve model treated with crude Naja kaouthia (NK) venom and also shows the effect of Phospholipase A2 and three finger neurotoxin from NK-venom on peripheral nerve. This opens future scope for non-invasive clinical measurement of demyelination.

  11. Rocket measurements within a polar cap arc - Plasma, particle, and electric circuit parameters

    Science.gov (United States)

    Weber, E. J.; Ballenthin, J. O.; Basu, S.; Carlson, H. C.; Hardy, D. A.; Maynard, N. C.; Kelley, M. C.; Fleischman, J. R.; Pfaff, R. F.

    1989-01-01

    Results are presented from the Polar Ionospheric Irregularities Experiment (PIIE), conducted from Sondrestrom, Greenland, on March 15, 1985, designed for an investigation of processes which lead to the generation of small-scale (less than 1 km) ionospheric irregularities within polar-cap F-layer auroras. An instrumented rocket was launched into a polar cap F layer aurora to measure energetic electron flux, plasma, and electric circuit parameters of a sun-aligned arc, coordinated with simultaneous measurements from the Sondrestrom incoherent scatter radar and the AFGL Airborne Ionospheric Observatory. Results indicated the existence of two different generation mechanisms on the dawnside and duskside of the arc. On the duskside, parameters are suggestive of an interchange process, while on the dawnside, fluctuation parameters are consistent with a velocity shear instability.

  12. Power electronic interface circuits for batteries and ultracapacitors in electric vehicles and battery storage systems

    Science.gov (United States)

    King, Robert Dean; DeDoncker, Rik Wivina Anna Adelson

    1998-01-01

    A method and apparatus for load leveling of a battery in an electrical power system includes a power regulator coupled to transfer power between a load and a DC link, a battery coupled to the DC link through a first DC-to-DC converter and an auxiliary passive energy storage device coupled to the DC link through a second DC-to-DC converter. The battery is coupled to the passive energy storage device through a unidirectional conducting device whereby the battery can supply power to the DC link through each of the first and second converters when battery voltage exceeds voltage on the passive storage device. When the load comprises a motor capable of operating in a regenerative mode, the converters are adapted for transferring power to the battery and passive storage device. In this form, resistance can be coupled in circuit with the second DC-to-DC converter to dissipate excess regenerative power.

  13. Quantifying Demyelination in NK venom treated nerve using its electric circuit model

    Science.gov (United States)

    Das, H. K.; Das, D.; Doley, R.; Sahu, P. P.

    2016-03-01

    Reduction of myelin in peripheral nerve causes critical demyelinating diseases such as chronic inflammatory demyelinating polyneuropathy, Guillain-Barre syndrome, etc. Clinical monitoring of these diseases requires rapid and non-invasive quantification of demyelination. Here we have developed formulation of nerve conduction velocity (NCV) in terms of demyelination considering electric circuit model of a nerve having bundle of axons for its quantification from NCV measurements. This approach has been validated and demonstrated with toad nerve model treated with crude Naja kaouthia (NK) venom and also shows the effect of Phospholipase A2 and three finger neurotoxin from NK-venom on peripheral nerve. This opens future scope for non-invasive clinical measurement of demyelination.

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

    DEFF Research Database (Denmark)

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

    2015-01-01

    emerging technology for various applications, there is a need for Li-S battery performance model; however, developing such models represents a challenging task due to batteries' complex ongoing chemical reactions. Therefore, the literature review was performed to summarize electrical circuit models (ECMs......) used for modeling the performance behavior of Li-S batteries. The studied Li-S pouch cell was tested in the laboratory in order to parametrize four basic ECM topologies. These topologies were compared by analyzing their voltage estimation accuracy values, which were obtained for different battery...... current profiles. Based on these results, the 3 R-C ECM was chosen and the Li-S battery cell discharging performance model with current dependent parameters was derived and validated....

  15. Electricity

    CERN Document Server

    Basford, Leslie

    2013-01-01

    Electricity Made Simple covers the fundamental principles underlying every aspect of electricity. The book discusses current; resistance including its measurement, Kirchhoff's laws, and resistors; electroheat, electromagnetics and electrochemistry; and the motor and generator effects of electromagnetic forces. The text also describes alternating current, circuits and inductors, alternating current circuits, and a.c. generators and motors. Other methods of generating electromagnetic forces are also considered. The book is useful for electrical engineering students.

  16. Developing an Empirical Model for Estimating the Probability of Electrical Short Circuits from Tin Whiskers. Part 2

    Science.gov (United States)

    Courey, Karim J.; Asfour, Shihab S.; Onar, Arzu; Bayliss, Jon A.; Ludwig, Larry L.; Wright, Maria C.

    2009-01-01

    To comply with lead-free legislation, many manufacturers have converted from tin-lead to pure tin finishes of electronic components. However, pure tin finishes have a greater propensity to grow tin whiskers than tin-lead finishes. Since tin whiskers present an electrical short circuit hazard in electronic components, simulations have been developed to quantify the risk of said short circuits occurring. Existing risk simulations make the assumption that when a free tin whisker has bridged two adjacent exposed electrical conductors, the result is an electrical short circuit. This conservative assumption is made because shorting is a random event that had an unknown probability associated with it. Note however that due to contact resistance electrical shorts may not occur at lower voltage levels. In our first article we developed an empirical probability model for tin whisker shorting. In this paper, we develop a more comprehensive empirical model using a refined experiment with a larger sample size, in which we studied the effect of varying voltage on the breakdown of the contact resistance which leads to a short circuit. From the resulting data we estimated the probability distribution of an electrical short, as a function of voltage. In addition, the unexpected polycrystalline structure seen in the focused ion beam (FIB) cross section in the first experiment was confirmed in this experiment using transmission electron microscopy (TEM). The FIB was also used to cross section two card guides to facilitate the measurement of the grain size of each card guide's tin plating to determine its finish.

  17. Maximizing the short circuit current of organic solar cells by partial decoupling of electrical and optical properties

    Science.gov (United States)

    Qarony, Wayesh; Hossain, Mohammad I.; Jovanov, Vladislav; Knipp, Dietmar; Tsang, Yuen Hong

    2018-03-01

    The partial decoupling of electronic and optical properties of organic solar cells allows for realizing solar cells with increased short circuit current and energy conversion efficiency. The proposed device consists of an organic solar cell conformally prepared on the surface of an array of single and double textured pyramids. The device geometry allows for increasing the optical thickness of the organic solar cell, while the electrical thickness is equal to the nominal thickness of the solar cell. By increasing the optical thickness of the solar cell, the short circuit current is distinctly increased. The quantum efficiency and short circuit current are determined using finite-difference time-domain simulations of the 3D solar cell structure. The influence of different solar cell designs on the quantum efficiency and short circuit current is discussed and optimal device dimensions are proposed.

  18. Highly conductive and ultrastretchable electric circuits from covered yarns and silver nanowires.

    Science.gov (United States)

    Cheng, Yin; Wang, Ranran; Sun, Jing; Gao, Lian

    2015-04-28

    Stretchable electronics, as a promising research frontier, has achieved progress in a variety of sophisticated applications. The realization of stretchable electronics frequently involves the demand for a stretchable conductor as an electrical circuit. However, it still remains a challenge to fabricate high-performance (working strain exceeding 200%) stretchable conductors. Here, we present for the first time a facile, cost-effective, and scalable method for manufacturing ultrastretchable composite fibers with a "twining spring" configuration: cotton fibers twining spirally around a polyurethane fiber. The composite fiber possesses a high conductivity up to 4018 S/cm, which remains as high as 688 S/cm at 500% tensile strain. In addition, the conductivity of the composite fiber (initial conductivity of 4018 S/cm) remains perfectly stable after 1000 bending events and levels off at 183 S/cm after 1000 cyclic stretching events of 200% strain. Stretchable LED arrays are integrated efficiently utilizing the composite fibers as a stretchable electric wiring system, demonstrating the potential applications in large-area stretchable electronics. The biocompatibility of the composite fiber is verified, opening up its prospects in the field of implantable devices. Our fabrication strategy is also versatile for the preparation of other specially functionalized composite fibers with superb stretchability.

  19. Conceptions of Pupils of the Primary on the Topic of an Electric Circuit in Three Countries (Canada, France and Morocco)

    Science.gov (United States)

    Métioui, Abdeljalil; MacWillie, Mireille Baulu; Trudel, Louis

    2016-01-01

    Qualitative research conducted with 237 pupils from Canada, France, and Morocco, between 10 and 12 years of age, on the setting and functioning of simple electric circuits, demonstrates that similar explanatory systems of the students. For this, we had given them a paper and pencil questionnaire of a sixty minutes duration. The first question was…

  20. The Effects on Students' Conceptual Understanding of Electric Circuits of Introducing Virtual Manipulatives within a Physical Manipulatives-Oriented Curriculum

    Science.gov (United States)

    Zacharia, Zacharias C.; de Jong, Ton

    2014-01-01

    This study investigates whether Virtual Manipulatives (VM) within a Physical Manipulatives (PM)-oriented curriculum affect conceptual understanding of electric circuits and related experimentation processes. A pre-post comparison study randomly assigned 194 undergraduates in an introductory physics course to one of five conditions: three…

  1. Using a Conflict Map as an Instructional Tool To Change Student Conceptions in Simple Series Electric-Circuits.

    Science.gov (United States)

    Tsai, Chin-Chung

    2003-01-01

    Examines the effects of using a conflict map on 8th grade students' conceptual change and ideational networks about simple series electric circuits. Analyzes student interview data through a flow map method. Shows that the use of conflict maps could help students construct greater, richer, and more integrated ideational networks about electric…

  2. Analogy for Drude's Free Electron Model to Promote Students' Understanding of Electric Circuits in Lower Secondary School

    Science.gov (United States)

    de Almeida, Maria José B. M.; Salvador, Andreia; Costa, Maria Margarida R. R.

    2014-01-01

    Aiming at a deep understanding of some basic concepts of electric circuits in lower secondary schools, this work introduces an analogy between the behavior of children playing in a school yard with a central lake, subject to different conditions, rules, and stimuli, and Drude's free electron model of metals. Using this analogy from the first…

  3. Self-Regulated Learning Strategies of Engineering College Students While Learning Electric Circuit Concepts with Enhanced Guided Notes

    Science.gov (United States)

    Lawanto, Oenardi; Santoso, Harry

    2013-01-01

    The current study evaluated engineering college students' self-regulated learning (SRL) strategies while learning electric circuit concepts using enhanced guided notes (EGN). Our goal was to describe how students exercise SRL strategies and how their grade performance changes after using EGN. Two research questions guided the study: (1) To what…

  4. The Confidence-Accuracy Relationship in Diagnostic Assessment: The Case of the Potential Difference in Parallel Electric Circuits

    Science.gov (United States)

    Saglam, Murat

    2015-01-01

    This study explored the relationship between accuracy of and confidence in performance of 114 prospective primary school teachers in answering diagnostic questions on potential difference in parallel electric circuits. The participants were required to indicate their confidence in their answers for each question. Bias and calibration indices were…

  5. A Comparison of Students' Conceptual Understanding of Electric Circuits in Simulation Only and Simulation-Laboratory Contexts

    Science.gov (United States)

    Jaakkola, Tomi; Nurmi, Sami; Veermans, Koen

    2011-01-01

    The aim of this experimental study was to compare learning outcomes of students using a simulation alone (simulation environment) with outcomes of those using a simulation in parallel with real circuits (combination environment) in the domain of electricity, and to explore how learning outcomes in these environments are mediated by implicit (only…

  6. Analogy for Drude’s free electron model to promote students’ understanding of electric circuits in lower secondary school

    Directory of Open Access Journals (Sweden)

    Maria José BM de Almeida

    2014-09-01

    Full Text Available Aiming at a deep understanding of some basic concepts of electric circuits in lower secondary schools, this work introduces an analogy between the behavior of children playing in a school yard with a central lake, subject to different conditions, rules, and stimuli, and Drude’s free electron model of metals. Using this analogy from the first school contacts with electric phenomena, one can promote students’ understanding of concepts such as electric current, the role of generators, potential difference effects, energy transfer, open and closed circuits, resistances, and their combinations in series and parallel. One believes that through this analogy well-known previous misconceptions of young students about electric circuit behaviors can be overcome. Furthermore, students’ understanding will enable them to predict, and justify with self-constructed arguments, the behavior of different elementary circuits. The students’ predictions can be verified—as a challenge of self-produced understanding schemes—using laboratory experiments. At a preliminary stage, our previsions were confirmed through a pilot study with three classrooms of 9th level Portuguese students.

  7. The Effects oF 4C-ID Model Approach on Acquisition and Transfer of Knowledge about Electric Circuits

    Science.gov (United States)

    Melo, Mário; Miranda, Guilhermina Lobato

    2018-01-01

    This paper reports the first results of an experimental research, carried out in a private school with 9th grade students, where the 4C/ID-model was used for teaching and learning electric circuits. The authors describe the principles and features of the instructional model, that is suitability for the teaching and learning of complex knowledge…

  8. EQUATIONS OF ELECTRIC MOTOR POWER SUPPLY UNIT DISSYMMETRY UNDER PHASE-TO-PHASE SHORT-CIRCUIT FAULT

    Directory of Open Access Journals (Sweden)

    V.Y. Tchaban

    2013-10-01

    Full Text Available In the paper, a formula is introduced to calculate electric motor supply unit voltage under feeding by a common transformer in the condition of a phase-to-phase short-circuit. The formula is used in every time step of electromechanical state equations integration.

  9. High Resolution Global Electrical Conductivity Variations in the Earth's Mantle

    Science.gov (United States)

    Kelbert, A.; Sun, J.; Egbert, G. D.

    2013-12-01

    Electrical conductivity of the Earth's mantle is a valuable constraint on the water content and melting processes. In Kelbert et al. (2009), we obtained the first global inverse model of electrical conductivity in the mantle capable of providing constraints on the lateral variations in mantle water content. However, in doing so we had to compromise on the problem complexity by using the historically very primitive ionospheric and magnetospheric source assumptions. In particular, possible model contamination by the auroral current systems had greatly restricted our use of available data. We have now addressed this problem by inverting for the external sources along with the electrical conductivity variations. In this study, we still focus primarily on long period data that are dominated by quasi-zonal source fields. The improved understanding of the ionospheric sources allows us to invert the magnetic fields directly, without a correction for the source and/or the use of transfer functions. It allows us to extend the period range of available data to 1.2 days - 102 days, achieving better sensitivity to the upper mantle and transition zone structures. Finally, once the source effects in the data are accounted for, a much larger subset of observatories may be used in the electrical conductivity inversion. Here, we use full magnetic fields at 207 geomagnetic observatories, which include mid-latitude, equatorial and high latitude data. Observatory hourly means from the years 1958-2010 are employed. The improved quality and spatial distribution of the data set, as well as the high resolution modeling and inversion using degree and order 40 spherical harmonics mapped to a 2x2 degree lateral grid, all contribute to the much improved resolution of our models, representing a conceptual step forward in global electromagnetic sounding. We present a fully three-dimensional, global electrical conductivity model of the Earth's mantle as inferred from ground geomagnetic

  10. Global EV Outlook: Understanding the Electric Vehicle Landscape to 2020

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-06-01

    The Global EV Outlook represents the collective efforts of two years of primary data gathering and analysis from the Electric Vehicles Initiative (EVI) and IEA. Key takeaways and insights include landscape analysis of electric vehicle (EV) stock/sales and charging station deployment. Existing policy initiatives are delineated and future opportunities highlighted in an ''Opportunity Matrix: Pathways to 2020''. Together EVI countries accounted for more than 90% of world EV stock at the end of 2012. Strong government support in EVI countries on both the supply and demand sides are contributing to rising market penetration. 12 out of 15 EVI countries offer financial support for vehicle purchases, and most employ a mix of financial and non-financial incentives (such as access to restricted highway lanes) to help drive adoption. The Global EV Outlook is a unique and data-rich overview of the state of electric vehicles today, and offers an understanding of the electric vehicle landscape to 2020.

  11. Module Seven: Combination Circuits and Voltage Dividers; Basic Electricity and Electronics Individualized Learning System.

    Science.gov (United States)

    Bureau of Naval Personnel, Washington, DC.

    In this module the student will learn to apply the rules previously learned for series and parallel circuits to more complex circuits called series-parallel circuits, discover the utility of a common reference when making reference to voltage values, and learn how to obtain a required voltage from a voltage divider network. The module is divided…

  12. Verification and Analysis of Implementing Virtual Electric Devices in Circuit Simulation of Pulsed DC Electrical Devices in the NI MULTISIM 10.1 Environment

    Directory of Open Access Journals (Sweden)

    V. A. Solov'ev

    2015-01-01

    Full Text Available The paper presents the analysis results of the implementation potential and evaluation of the virtual electric devices reliability when conducting circuit simulation of pulsed DC electrical devices in the NI Multisim 10.1environment. It analyses metrological properties of electric measuring devices and sensors of the NI Multisim 10.1environment. To calculate the reliable parameters of periodic non-sinusoidal electrical values based on their physical feasibility the mathematical expressions have been defined.To verify the virtual electric devices a circuit model of the power section of buck DC converter with enabled devices under consideration at its input and output is used as a consumer of pulse current of trapezoidal or triangular form. It is used as an example to show a technique to verify readings of virtual electric measuring devices in the NI Multisim 10.1environment.It is found that when simulating the pulsed DC electric devices to measure average and RMS voltage supply and current consumption values it is advisable to use the probe. Electric device power consumption read from the virtual power meter is equal to its average value, and its displayed power factor is inversely proportional to the input current form factor. To determine the RMS pulsed DC current by ammeter and multi-meter it is necessary to measure current by these devices in DC and AC modes, and then determine the RMS value of measurement results.Virtual electric devices verification has proved the possibility of their application to determine the energy performance of transistor converters for various purposes in the circuit simulation in the NI 10.1 Multisim environment, thus saving time of their designing.

  13. Electrical circuits of an electromagnetic isotope separator; Circuits electriques d'un separateur d'isotopes electromagnetique

    Energy Technology Data Exchange (ETDEWEB)

    Neyron, A. [Commissariat a l' energie atomique et aux energies alternatives - CEA, Centre d' etudes nucleaires de Saclay (France)

    1959-07-01

    After an outline of the general principles governing the operation of an electromagnetic isotope separator, the electrical characteristics necessary to this operation are given. First the electrical characteristics of the ion source are briefly presented. The author then gives a detailed account of the construction of the H.T. acceleration supply of which the maxima characteristics are 80 kV and 150 mA with stabilisation of the order of 4.10{sup -4}. Reprint of a paper published in 'Industries Atomiques' - n. 3-4, 1959.

  14. A Practical Circuit-based Model for State of Health Estimation of Li-ion Battery Cells in Electric Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Lam, Long

    2011-08-23

    In this thesis the development of the state of health of Li-ion battery cells under possible real-life operating conditions in electric cars has been characterised. Furthermore, a practical circuit-based model for Li-ion cells has been developed that is capable of modelling the cell voltage behaviour under various operating conditions. The Li-ion cell model can be implemented in simulation programs and be directly connected to a model of the rest of the electronic system in electric vehicles. Most existing battery models are impractical for electric vehicle system designers and require extensive background knowledge of electrochemistry to be implemented. Furthermore, many models do not take the effect of regenerative braking into account and are obtained from testing fully charged cells. However, in real-life applications electric vehicles are not always fully charged and utilise regenerative braking to save energy. To obtain a practical circuit model based on real operating conditions and to model the state of health of electric vehicle cells, numerous 18650 size LiFePO4 cells have been tested under possible operating conditions. Capacity fading was chosen as the state of health parameter, and the capacity fading of different cells was compared with the charge processed instead of cycles. Tests have shown that the capacity fading rate is dependent on temperature, charging C-rate, state of charge and depth of discharge. The obtained circuit model is capable of simulating the voltage behaviour under various temperatures and C-rates with a maximum error of 14mV. However, modelling the effect of different temperatures and C-rates increases the complexity of the model. The model is easily adjustable and the choice is given to the electric vehicle system designer to decide which operating conditions to take into account. By combining the test results for the capacity fading and the proposed circuit model, recommendations to optimise the battery lifetime are proposed.

  15. Displacement damage analysis and modified electrical equivalent circuit for electron and photon-irradiated silicon solar cells

    Science.gov (United States)

    Arjhangmehr, Afshin; Feghhi, Seyed Amir Hossein

    2014-10-01

    Solar modules and arrays are the conventional energy resources of space satellites. Outside the earth's atmosphere, solar panels experience abnormal radiation environments and because of incident particles, photovoltaic (PV) parameters degrade. This article tries to analyze the electrical performance of electron and photon-irradiated mono-crystalline silicon (mono-Si) solar cells. PV cells are irradiated by mono-energetic electrons and poly-energetic photons and immediately characterized after the irradiation. The mean degradation of the maximum power (Pmax) of silicon solar cells is presented and correlated using the displacement damage dose (Dd) methodology. This method simplifies evaluation of cell performance in space radiation environments and produces a single characteristic curve for Pmax degradation. Furthermore, complete analysis of the results revealed that the open-circuit voltage (Voc) and the filling factor of mono-Si cells did not significantly change during the irradiation and were independent of the radiation type and fluence. Moreover, a new technique is developed that adapts the irradiation-induced effects in a single-cell equivalent electrical circuit and adjusts its elements. The "modified circuit" is capable of modeling the "radiation damage" in the electrical behavior of mono-Si solar cells and simplifies the designing of the compensation circuits.

  16. Study of time dependence and spectral composition of the signal in circuit of ac electric point motors

    Directory of Open Access Journals (Sweden)

    S. Yu. Buryak

    2014-12-01

    Full Text Available Purpose. The paper is aimed to establish the dependence of changes in the time domain and spectral components of the current in the circuit of the AC electric point motor on its technical condition, to identify the common features for the same type of damage. It is necessary using the analysis of the received signals to carry out the remote diagnosis and determination of faults and defects of electric point motors. In addition it suggested to accelerate the process of the failure, malfunction and damage search. Authors propose the automated approach to the service of remote floor automation equipment, which is located in the envelope of trains. Reduction of the threat to life and health of staff by reducing the residence time in the zone of train movement. Reduce the impact of human factors on the result of service. Methodology. The paper studies the structure, parameters and characteristics, the operation and maintenance characteristics of the AC electric point motors. Determination of the main types of possible faults in the process depending on the operating conditions. Presentation of the electric motor as an object of diagnosis. Findings. The time dependences of the current in the circuit of electric point motor for its various states was obtained. The connection between the technical condition of electric point motor and the performance of current curve in time and spectral domains was established. The revealed deviations from the reference signal were justified. According to the obtained results it was made the conclusion. Originality. A method for diagnosing the state of the AC electric point motor by the time dependence and the spectral composition of the current in its circuit was proposed. The connection diagram to the motor windings based on non-infringement of electric parameters of connection circuit in the actual operating conditions was applied. Practical value. The obtained results suggest the possibility and feasibility of

  17. Circuit analysis for dummies

    CERN Document Server

    Santiago, John

    2013-01-01

    Circuits overloaded from electric circuit analysis? Many universities require that students pursuing a degree in electrical or computer engineering take an Electric Circuit Analysis course to determine who will ""make the cut"" and continue in the degree program. Circuit Analysis For Dummies will help these students to better understand electric circuit analysis by presenting the information in an effective and straightforward manner. Circuit Analysis For Dummies gives you clear-cut information about the topics covered in an electric circuit analysis courses to help

  18. Real-time monitoring of a microbial electrolysis cell using an electrical equivalent circuit model.

    Science.gov (United States)

    Hussain, S A; Perrier, M; Tartakovsky, B

    2018-04-01

    Efforts in developing microbial electrolysis cells (MECs) resulted in several novel approaches for wastewater treatment and bioelectrosynthesis. Practical implementation of these approaches necessitates the development of an adequate system for real-time (on-line) monitoring and diagnostics of MEC performance. This study describes a simple MEC equivalent electrical circuit (EEC) model and a parameter estimation procedure, which enable such real-time monitoring. The proposed approach involves MEC voltage and current measurements during its operation with periodic power supply connection/disconnection (on/off operation) followed by parameter estimation using either numerical or analytical solution of the model. The proposed monitoring approach is demonstrated using a membraneless MEC with flow-through porous electrodes. Laboratory tests showed that changes in the influent carbon source concentration and composition significantly affect MEC total internal resistance and capacitance estimated by the model. Fast response of these EEC model parameters to changes in operating conditions enables the development of a model-based approach for real-time monitoring and fault detection.

  19. Microdosimetric study for nanosecond pulsed electric fields on a cell circuit model with nucleus.

    Science.gov (United States)

    Denzi, Agnese; Merla, Caterina; Camilleri, Paola; Paffi, Alessandra; d'Inzeo, Guglielmo; Apollonio, Francesca; Liberti, Micaela

    2013-10-01

    Recently, scientific interest in electric pulses, always more intense and shorter and able to induce biological effects on both plasma and nuclear membranes, has greatly increased. Hence, microdosimetric models that include internal organelles like the nucleus have assumed increasing importance. In this work, a circuit model of the cell including the nucleus is proposed, which accounts for the dielectric dispersion of all cell compartments. The setup of the dielectric model of the nucleus is of fundamental importance in determining the transmembrane potential (TMP) induced on the nuclear membrane; here, this is demonstrated by comparing results for three different sets of nuclear dielectric properties present in the literature. The results have been compared, even including or disregarding the dielectric dispersion of the nucleus. The main differences have been found when using pulses shorter than 10 ns. This is due to the fact that the high spectral components of the shortest pulses are differently taken into account by the nuclear membrane transfer functions computed with and without nuclear dielectric dispersion. The shortest pulses are also the most effective in porating the intracellular structures, as confirmed by the time courses of the TMP calculated across the plasma and nuclear membranes. We show how dispersive nucleus models are unavoidable when dealing with pulses shorter than 10 ns because of the large spectral contents arriving above 100 MHz, i.e., over the typical relaxation frequencies of the dipolar mechanism of the molecules constituting the nuclear membrane and the subcellular cell compartments.

  20. Investigating the role of socially mediated metacognition during collaborative troubleshooting of electric circuits

    Directory of Open Access Journals (Sweden)

    Kevin L. Van De Bogart

    2017-09-01

    Full Text Available Developing students’ ability to troubleshoot is an important learning outcome for many undergraduate physics lab courses, especially electronics courses. In other work, metacognition has been identified as an important feature of troubleshooting. However, that work has focused primarily on individual students’ metacognitive processes or troubleshooting abilities. In contrast, electronics courses often require students to work in pairs, and hence students’ in-class experiences likely have significant social dimensions that are not well understood. In this work, we use an existing framework for socially mediated metacognition to analyze audiovisual data from think-aloud activities in which eight pairs of students from two institutions attempted to diagnose and repair a malfunctioning electric circuit. In doing so, we provide insight into some of the social metacognitive dynamics that arise during collaborative troubleshooting. We find that students engaged in socially mediated metacognition at multiple key transitions during the troubleshooting process. Reciprocated metacognitive dialogue arose when students were collectively strategizing about which measurements to perform, or reaching a shared understanding of the circuit’s behavior. Our research demonstrates the value of the framework of socially mediated metacognition in providing insight into the nature of collaborative student troubleshooting in the context of electronics. As such, this framework may be a useful resource for future efforts to examine and support the development of student troubleshooting skills in other upper-division laboratory courses.

  1. 76 FR 30325 - Application to Export Electric Energy; E-T Global Energy, LLC

    Science.gov (United States)

    2011-05-25

    ... Export Electric Energy; E-T Global Energy, LLC AGENCY: Office of Electricity Delivery and Energy... authority to transmit electric energy from the United States to Mexico pursuant to section 202(e) of the... an application from E-T Global for authority to transmit electric energy from the United States to...

  2. On global environment problems in electric power business

    International Nuclear Information System (INIS)

    Sugi, Masashi

    1992-01-01

    The former environmental problems were atmospheric pollution, water quality contamination, noise and vibration nuisance, waste disposal and so on mainly at interior or district level, but now, the influence that the problems such as the global warming due to carbon dioxide emission, the ozone layer breaking due to freon gas, acid rain going over boundaries and so on exert to environment spreads to wide areas, therefore, various research and investigation have been carried out as the environmental problems on global scale at national and international levels. It has become an important subject to make the preservation of global environment and durable economical development compatible by effectively utilizing limited resources and energy. The electric power companies have advanced positively the prevention of pollution and the preservation of environment, and attained the environment preservation of top level in the world. The consciousness of people on environmental problems has heightened, therefore the construction and operation of power plants harmonized to districts are important. The countermeasures to environmental problems taken by electric power companies are reported. (K.I.)

  3. AC and DC electrical behavior of MWCNT/epoxy nanocomposite near percolation threshold: Equivalent circuits and percolation limits

    Science.gov (United States)

    Alizadeh Sahraei, Abolfazl; Ayati, Moosa; Baniassadi, Majid; Rodrigue, Denis; Baghani, Mostafa; Abdi, Yaser

    2018-03-01

    This study attempts to comprehensively investigate the effects of multi-walled carbon nanotubes (MWCNTs) on the AC and DC electrical conductivity of epoxy nanocomposites. The samples (0.2, 0.3, and 0.5 wt. % MWCNT) were produced using a combination of ultrason and shear mixing methods. DC measurements were performed by continuous measurement of the current-voltage response and the results were analyzed via a numerical percolation approach, while for the AC behavior, the frequency response was studied by analyzing phase difference and impedance in the 10 Hz to 0.2 MHz frequency range. The results showed that the dielectric parameters, including relative permittivity, impedance phase, and magnitude, present completely different behaviors for the frequency range and MWCNT weight fractions studied. To better understand the nanocomposites electrical behavior, equivalent electric circuits were also built for both DC and AC modes. The DC equivalent networks were developed based on the current-voltage curves, while the AC equivalent circuits were proposed by using an optimization problem according to the impedance magnitude and phase at different frequencies. The obtained equivalent electrical circuits were found to be highly useful tools to understand the physical mechanisms involved in MWCNT filled polymer nanocomposites.

  4. Electrical and electronic waste: a global environmental problem.

    Science.gov (United States)

    Ramesh Babu, Balakrishnan; Parande, Anand Kuber; Ahmed Basha, Chiya

    2007-08-01

    The production of electrical and electronic equipment (EEE) is one of the fastest growing global manufacturing activities. This development has resulted in an increase of waste electric and electronic equipment (WEEE). Rapid economic growth, coupled with urbanization and growing demand for consumer goods, has increased both the consumption of EEE and the production of WEEE, which can be a source of hazardous wastes that pose a risk to the environment and to sustainable economic growth. To address potential environmental problems that could stem from improper management of WEEE, many countries and organizations have drafted national legislation to improve the reuse, recycling and other forms of material recovery from WEEE to reduce the amount and types of materials disposed in landfills. Recycling of waste electric and electronic equipment is important not only to reduce the amount of waste requiring treatment, but also to promote the recovery of valuable materials. EEE is diverse and complex with respect to the materials and components used and waste streams from the manufacturing processes. Characterization of these wastes is of paramount importance for developing a cost-effective and environmentally sound recycling system. This paper offers an overview of electrical and e-waste recycling, including a description of how it is generated and classified, strategies and technologies for recovering materials, and new scientific developments related to these activities. Finally, the e-waste recycling industry in India is also discussed.

  5. NRC Information No. 87-41: Failures of certain Brown Boveri Electric circuit breakers

    International Nuclear Information System (INIS)

    Rossi, C.E.

    1992-01-01

    On April 20, 1987, Duquesne Light Company, the Beaver Valley Unit 2 licensee, notified the NRC of the failure of a BBE Type 5HK Class IE 4-KV circuit breaker. When the circuit breaker was racked onto the bus and 125-V DC control power was applied to the breaker's control circuit, the closing spring charged and the circuit breaker immediately closed and opened several times before the control power could be turned off. The licensee determined by field testing that the closing coil was not being energized. Another problem with BBE circuit breakers occurred at River Bend and was reported March 6, 1987. On February 6, 1987, with the unit at full power, the Division I diesel generator 4.16-KV output circuit breaker (Gould-Brown Boveri Type 5HK) failed to close during a weekly surveillance test. The licensee's inspection of the output circuit breaker revealed that a mounting bolt had fallen out of the closing spring charging motor, rendering the motor inoperable. Further investigation revealed several other circuit breakers that contained loose or missing charging motor mounting bolts. The licensee also stated that the River Bend circuit breaker preventive maintenance program, which the licensee believes to be in accordance with the vendor's recommendations, did not detect this problem. The licensee believes the root cause of the problem to be insufficient torquing of the charging motor mounting bolts by the vendor

  6. Acquiring Knowledge in Learning Concepts from Electrical Circuits: The Use of Multiple Representations in Technology-Based Learning Environments

    Directory of Open Access Journals (Sweden)

    Abdeljalil Métioui

    2012-04-01

    Full Text Available The constructivists approach on the conception of relative software of modelling to training and teaching of the concepts of current and voltage requires appraisal of several disciplinary fields in order to provide to the learners a training adapted to their representations. Thus, this approach requires the researchers to have adequate knowledge or skills in data processing, didactics and science content. In this regard, several researches underline that the acquisition of basic concepts that span a field of a given knowledge, must take into account the student and the scientific representations. The present research appears in this perspective, and aims to present the interactive computer environments that take into account the students (secondary and college and scientific representations related to simple electric circuits. These computer environments will help the students to analyze the functions of the electric circuits adequately.

  7. A LabVIEW-based electrical bioimpedance spectroscopic data interpreter (LEBISDI) for biological tissue impedance analysis and equivalent circuit modelling

    KAUST Repository

    Bera, Tushar Kanti

    2016-12-05

    Under an alternating electrical signal, biological tissues produce a complex electrical bioimpedance that is a function of tissue composition and applied signal frequencies. By studying the bioimpedance spectra of biological tissues over a wide range of frequencies, we can noninvasively probe the physiological properties of these tissues to detect possible pathological conditions. Electrical impedance spectroscopy (EIS) can provide the spectra that are needed to calculate impedance parameters within a wide range of frequencies. Before impedance parameters can be calculated and tissue information extracted, impedance spectra should be processed and analyzed by a dedicated software program. National Instruments (NI) Inc. offers LabVIEW, a fast, portable, robust, user-friendly platform for designing dataanalyzing software. We developed a LabVIEW-based electrical bioimpedance spectroscopic data interpreter (LEBISDI) to analyze the electrical impedance spectra for tissue characterization in medical, biomedical and biological applications. Here, we test, calibrate and evaluate the performance of LEBISDI on the impedance data obtained from simulation studies as well as the practical EIS experimentations conducted on electronic circuit element combinations and the biological tissue samples. We analyze the Nyquist plots obtained from the EIS measurements and compare the equivalent circuit parameters calculated by LEBISDI with the corresponding original circuit parameters to assess the accuracy of the program developed. Calibration studies show that LEBISDI not only interpreted the simulated and circuitelement data accurately, but also successfully interpreted tissues impedance data and estimated the capacitive and resistive components produced by the compositions biological cells. Finally, LEBISDI efficiently calculated and analyzed variation in bioimpedance parameters of different tissue compositions, health and temperatures. LEBISDI can also be used for human tissue

  8. A LabVIEW-based electrical bioimpedance spectroscopic data interpreter (LEBISDI) for biological tissue impedance analysis and equivalent circuit modelling

    KAUST Repository

    Bera, Tushar Kanti; Jampana, Nagaraju; Lubineau, Gilles

    2016-01-01

    Under an alternating electrical signal, biological tissues produce a complex electrical bioimpedance that is a function of tissue composition and applied signal frequencies. By studying the bioimpedance spectra of biological tissues over a wide range of frequencies, we can noninvasively probe the physiological properties of these tissues to detect possible pathological conditions. Electrical impedance spectroscopy (EIS) can provide the spectra that are needed to calculate impedance parameters within a wide range of frequencies. Before impedance parameters can be calculated and tissue information extracted, impedance spectra should be processed and analyzed by a dedicated software program. National Instruments (NI) Inc. offers LabVIEW, a fast, portable, robust, user-friendly platform for designing dataanalyzing software. We developed a LabVIEW-based electrical bioimpedance spectroscopic data interpreter (LEBISDI) to analyze the electrical impedance spectra for tissue characterization in medical, biomedical and biological applications. Here, we test, calibrate and evaluate the performance of LEBISDI on the impedance data obtained from simulation studies as well as the practical EIS experimentations conducted on electronic circuit element combinations and the biological tissue samples. We analyze the Nyquist plots obtained from the EIS measurements and compare the equivalent circuit parameters calculated by LEBISDI with the corresponding original circuit parameters to assess the accuracy of the program developed. Calibration studies show that LEBISDI not only interpreted the simulated and circuitelement data accurately, but also successfully interpreted tissues impedance data and estimated the capacitive and resistive components produced by the compositions biological cells. Finally, LEBISDI efficiently calculated and analyzed variation in bioimpedance parameters of different tissue compositions, health and temperatures. LEBISDI can also be used for human tissue

  9. Performance evaluation of parallel electric field tunnel field-effect transistor by a distributed-element circuit model

    Science.gov (United States)

    Morita, Yukinori; Mori, Takahiro; Migita, Shinji; Mizubayashi, Wataru; Tanabe, Akihito; Fukuda, Koichi; Matsukawa, Takashi; Endo, Kazuhiko; O'uchi, Shin-ichi; Liu, Yongxun; Masahara, Meishoku; Ota, Hiroyuki

    2014-12-01

    The performance of parallel electric field tunnel field-effect transistors (TFETs), in which band-to-band tunneling (BTBT) was initiated in-line to the gate electric field was evaluated. The TFET was fabricated by inserting an epitaxially-grown parallel-plate tunnel capacitor between heavily doped source wells and gate insulators. Analysis using a distributed-element circuit model indicated there should be a limit of the drain current caused by the self-voltage-drop effect in the ultrathin channel layer.

  10. Pulse mode of operation of a spherical piezoceramic transducer filled with liquid and having a correcting electric circuit.

    Science.gov (United States)

    Konovalov, S I; Kuz'menko, A G

    2010-12-01

    By means of a computational method, the possibility of radiating a short acoustic pulse by a transducer in the form of a piezoceramic sphere internally filled with liquid is investigated. An electric inductive-resistive circuit is connected to the electric input of the transducer. Solution is obtained based on scheme-analogs theory for piezoceramic transducers, and spectral Fourier transform theory. The values of parameters of the system, providing minimal durations of radiated signals, are determined. Computation was carried out for different values of relative thicknesses of the transducer wall. The estimates of durations and amplitudes of the acoustic signals radiated into the external medium are obtained.

  11. Electronic circuit SG-6 type for electric differential manometer in the flow rate measuring system

    Energy Technology Data Exchange (ETDEWEB)

    Glowacki, S W; Pytel, K; Beldzikowski, W

    1978-01-01

    A system measuring the flow rate of a liquid or gas employing a ruft and a differential manometer needs the square rooting circuit providing the linearity of the output signal to the measured flow rate ratio. The paper describes the electronic circuit developed for this purpose.

  12. Module Six: Parallel Circuits; Basic Electricity and Electronics Individualized Learning System.

    Science.gov (United States)

    Bureau of Naval Personnel, Washington, DC.

    In this module the student will learn the rules that govern the characteristics of parallel circuits; the relationships between voltage, current, resistance and power; and the results of common troubles in parallel circuits. The module is divided into four lessons: rules of voltage and current, rules for resistance and power, variational analysis,…

  13. Disassembly and physical separation of electric/electronic components layered in printed circuit boards (PCB).

    Science.gov (United States)

    Lee, Jaeryeong; Kim, Youngjin; Lee, Jae-chun

    2012-11-30

    Although printed circuit boards (PCBs) contain various elements, only the major elements (i.e., those with content levels in wt% or over grade) of and precious metals (e.g., Ag, Au, and platinum groups) contained within PCBs can be recycled. To recover other elements from PCBs, the PCBs should be properly disassembled as the first step of the recycling process. The recovery of these other elements would be beneficial for efforts to conserve scarce resources, reuse electric/electronic components (EECs), and eliminate environmental problems. This paper examines the disassembly of EECs from wasted PCBs (WPCBs) and the physical separation of these EECs using a self-designed disassembling apparatus and a 3-step separation process of sieving, magnetic separation, and dense medium separation. The disassembling efficiencies were evaluated by using the ratio of grinding area (E(area)) and the weight ratio of the detached EECs (E(weight)). In the disassembly treatment, these efficiencies were improved with an increase of grinder speed and grinder height. 97.7% (E(area)) and 98% (E(weight)) could be accomplished ultimately by 3 repetitive treatments at a grinder speed of 5500 rpm and a grinder height of 1.5mm. Through a series of physical separations, most groups of the EECs (except for the diode, transistor, and IC chip groups) could be sorted at a relatively high separation efficiency of about 75% or more. To evaluate the separation efficiency with regard to the elemental composition, the distribution ratio (R(dis)) and the concentration ratio (R(conc)) were used. 15 elements could be separated with the highest R(dis) and R(conc) in the same separated division. This result implies that the recyclability of the elements is highly feasible, even though the initial content in EECs is lower than several tens of mg/kg. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. Various mechanisms and clinical phenotypes in electrical short circuits of high-voltage devices: report of four cases and review of the literature.

    Science.gov (United States)

    Tsurugi, Takuo; Matsui, Shogo; Nakajima, Hiroshi; Nishii, Nobuhiro; Honda, Toshihiro; Kaneko, Yoshiaki

    2015-06-01

    An electrical short circuit is a rare complication in a high-voltage implantable cardioverter-defibrillator (ICD). However, the inability of an ICD to deliver appropriate shock therapy can be life-threatening. During the last 2 years, four cases of serious complications related to an electrical short circuit have been reported in Japan. A spark due to an electrical short circuit resulted in the failure of an ICD shock to terminate ventricular tachycardia and total damage to the ICD generator in three of four cases. Two of the four patients died from an electrical short circuit between the right ventricle and superior vena cava (SVC) leads. The others had audible sounds from the ICD generator site and were diagnosed with a lead-to-can abrasion, which was manifested by the arc mark on the surface of the can. It is still difficult to predict the occurrence of an electrical short circuit in current ICD systems. To reduce the probability of an electrical short circuit, we suggest the following: (i) avoid lead stress at ICD implantation, (ii) select a single-coil lead instead of a dual-coil lead, or (iii) use a unique algorithm which automatically disconnect can or SVC lead from shock deliver circuit when excessive current was detected. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  15. Resources transfer and centralization in Brazilian electrical sector: the reversion global reserve (RGR) and the guarantee global reserve (GGR)

    International Nuclear Information System (INIS)

    Souza Amaral Filho, J.B. de.

    1991-01-01

    This dissertation makes the analysis of resources transfer and centralization in Brazilian electrical sector, through reversion global reserve (RGR) and guarantee global reserve (GGR). RGR and GGR are funds. RGR finances sectorial investments in electric power and GGR aims the supply of deficient concessionaires. Governmental investments and the results of this application are showing. (M.V.M.). 55 refs, 2 figs, 61 tabs

  16. Effects of the Physical Laboratory versus the Virtual Laboratory in Teaching Simple Electric Circuits on Conceptual Achievement and Attitudes Towards the Subject

    Science.gov (United States)

    Tekbiyik, Ahmet; Ercan, Orhan

    2015-01-01

    Current study examined the effects of virtual and physical laboratory practices on students' conceptual achievement in the subject of electricity and their attitudes towards simple electric circuits. Two groups (virtual and physical) selected through simple random sampling was taught with web-aided material called "Electricity in Our…

  17. The principle of elaboration of the relay protection against short circuits between the closely placed phases of high voltage electrical line

    Directory of Open Access Journals (Sweden)

    Kiorsak M.

    2015-12-01

    Full Text Available The article is devoted to the elaboration of the principle of relay protection against short circuits between the closely placed phases of higher voltage electrical line with self-compensation, based on the six phase’s symmetrical components. It is shown that the unsymmetrical short circuits between the closely placed phases are characterized by appearance of zero and tertiary sequences of symmetrical components. This fact can be used to choose them for relay protection. The electrical basic circuits and formulas for calculation of the passive parameters of zero and tertiary filters of currents (voltages are done. It is presented the structural-functional basic circuit scheme for relay protection against short circuits between the closely placed phases of higher voltage electrical line with self-compensation.

  18. CIRCUIT-DESIGN SOLUTIONS AND INFORMATION SUPPORT OF CITY ELECTRIC NETWORKS IN THE CONDITIONS OF THE SMART GRID

    Directory of Open Access Journals (Sweden)

    M. I. Fursanov

    2017-01-01

    Full Text Available The structure, circuit-design solutions and information support of the city electric networks in the conditions of the SMART GRID have been analyzed. It is demonstrated that the new conditions of functioning of electric power engineering, increasing demands for its technological state and reliability in most countries determined the transition to a restructuring of electrical networks to be based on the SMART GRID (intelligent power networks innovative new structure. The definitions of the SMART GRID, its various attributes and characteristics in most developed countries including Belarus are presented. It is revealed that the existing and future circuit and constructive solutions that can automate the process of managing modes of urban electric networks under the SMART GRID conditions are manifold. At present, the most common in distribution networks are the sources of distributed generation (combustion turbines, wind turbines, photovoltaic installations, mini-hydro, etc.. The patterns and problems of information traceability of a traditional urban networks of the unified energy system of Belarus have been analyzed, and it is demonstrated that in the conditions of the SMART GRID most of the problems of the control mode that are characteristic for traditional distribution networks 6–10 kV and 0.38 kV, lose their relevance. Therefore, the present article presents and features the main directions of development of automatic control modes of the SMART GRID.

  19. Comparison of the AWA lumped-circuit model of electrical discharges with empirical data

    International Nuclear Information System (INIS)

    Maier, W.B. II; Kadish, A.; Robiscoe, R.T.

    1990-01-01

    The authors compare experimental data for three 1.7-m-long transient discharges with an AWA lumped- circuit discharge model in which the arc resistance is taken from the Arc Welder's Ansatz, R a = V*/|I |, where V* is a positive constant and I is the discharge current. In addition to the arc resistance, there is a small series resistance R present in the external circuit. A single value for each of R and V* is deduced from the data, and these values are used to characterize all three discharges. Adequate agreement with the experimental data is obtained; for example, the authors predict the proper number of current reversals for each discharge and abrupt termination of current flow after a finite time. The authors suggest that the AWA lumped circuit provides a better representation of the data than a standard lumped-circuit RLC model and hence is more useful as a tool for prediction and interpretation of discharges

  20. Short-Circuit Fault Detection and Classification Using Empirical Wavelet Transform and Local Energy for Electric Transmission Line.

    Science.gov (United States)

    Huang, Nantian; Qi, Jiajin; Li, Fuqing; Yang, Dongfeng; Cai, Guowei; Huang, Guilin; Zheng, Jian; Li, Zhenxin

    2017-09-16

    In order to improve the classification accuracy of recognizing short-circuit faults in electric transmission lines, a novel detection and diagnosis method based on empirical wavelet transform (EWT) and local energy (LE) is proposed. First, EWT is used to deal with the original short-circuit fault signals from photoelectric voltage transformers, before the amplitude modulated-frequency modulated (AM-FM) mode with a compactly supported Fourier spectrum is extracted. Subsequently, the fault occurrence time is detected according to the modulus maxima of intrinsic mode function (IMF₂) from three-phase voltage signals processed by EWT. After this process, the feature vectors are constructed by calculating the LE of the fundamental frequency based on the three-phase voltage signals of one period after the fault occurred. Finally, the classifier based on support vector machine (SVM) which was constructed with the LE feature vectors is used to classify 10 types of short-circuit fault signals. Compared with complementary ensemble empirical mode decomposition with adaptive noise (CEEMDAN) and improved CEEMDAN methods, the new method using EWT has a better ability to present the frequency in time. The difference in the characteristics of the energy distribution in the time domain between different types of short-circuit faults can be presented by the feature vectors of LE. Together, simulation and real signals experiment demonstrate the validity and effectiveness of the new approach.

  1. Improving the electromagnetic compatibility of track circuits with electric rolling stock of double power supply with induction traction motors and electrictraction network

    Directory of Open Access Journals (Sweden)

    N.G. Visin

    2012-04-01

    Full Text Available In this article the research results of many authors on the effect of current interference from the existing electric rolling stock with induction traction motors (ITM on the track circuits and the possibility of exceeding the train traffic safety standards are used. The new promising scheme of power circuit for electric locomotive of double power supply with an ITM applying the intermediary high-frequency transformer for reducing significantly the interference effects to SCB and communication devices is developed.

  2. Effects of a parallel resistor on electrical characteristics of a piezoelectric transformer in open-circuit transient state.

    Science.gov (United States)

    Chang, Kuo-Tsai

    2007-01-01

    This paper investigates electrical transient characteristics of a Rosen-type piezoelectric transformer (PT), including maximum voltages, time constants, energy losses and average powers, and their improvements immediately after turning OFF. A parallel resistor connected to both input terminals of the PT is needed to improve the transient characteristics. An equivalent circuit for the PT is first given. Then, an open-circuit voltage, involving a direct current (DC) component and an alternating current (AC) component, and its related energy losses are derived from the equivalent circuit with initial conditions. Moreover, an AC power control system, including a DC-to-AC resonant inverter, a control switch and electronic instruments, is constructed to determine the electrical characteristics of the OFF transient state. Furthermore, the effects of the parallel resistor on the transient characteristics at different parallel resistances are measured. The advantages of adding the parallel resistor also are discussed. From the measured results, the DC time constant is greatly decreased from 9 to 0.04 ms by a 10 k(omega) parallel resistance under open output.

  3. Europe in the global race for electrical batteries

    International Nuclear Information System (INIS)

    Mathieu, Carole

    2017-07-01

    This study weighs up the different strategic approaches that Europe may adopt in the industrial race for electrical batteries, taking into account the demand potential for e-mobility and stationary storage, the global competitive landscape and the policy support for local players in Asia and the U.S. The future looks bright for battery storage technologies. They could be the answer to the grid constraints that come with the rise of intermittent renewable electricity, while opening the door to the electrification of the transport sector and a reduction of its carbon footprint. Significant improvements in terms of performance and manufacturing costs have been achieved in recent years, thanks to the development of portable electronic devices and the push for lithium-ion solutions. The prospect of widening the client base to the automobile and energy industries is now triggering a massive wave of investment in battery manufacturing capacities. Economies of scale and increasing pressure on margins should make battery technologies even more affordable, and facilitate their adoption beyond public support schemes. A true industrial race is launched, but it takes place primarily in Asia, and to a lesser extent in North America. In these regions, public authorities are already proactive in promoting local industrial players on a global market that is buoyant but still highly risky. Unless the European Union reacts swiftly, it could see its internal demand being primarily covered by non-European manufacturers. While the EU has strong academic and industrial assets in the battery field, it risks being left behind the new mass markets if it proves unable to support the European battery industry with concerted efforts. The challenge is twofold: seizing a major opportunity in terms of growth and job creation, while preventing the emergence of major technology dependence

  4. Performance of the electrical generator cell by the ferrous alloys of printed circuit board scrap and Iron Metal 1020

    Science.gov (United States)

    Sahan, Y.; Sudarsono, S.; Silviana, E.; Chairul; Wisrayetti

    2018-04-01

    Galvani cell is one of thealternative energy. This cell can be used as an electric resources. In this research, the generator cell was designed and builds to generate the electric. The generator cell consisted of the iron metal 1020 were used as anode, the ferrous alloys of printed circuit board scrapwas then used as chatode, and NaCl solution as an electrolyte. The aim of this research is to estimate the performance of this generator cell by using variation of NaCl concentration (i.e. 1%, 3%, 5%, 7%, and 9%) with the electrodes pair ( 1 and 8 pairs). The performance of the cell was measured with a multi tester equipment and a LED bulb (5-watt 3Volt). The Results shown that the generator cell can produce the electric power of 3.679 Volt maximally by using NaCl 9% and 8 electrode pairs applied for this condition.

  5. IMPROVING THE RELIABILITY OF THE POWER CIRCUIT OF THE ELECTRIC TRAINS ЕР2Т AND ЕПЛ2Т

    Directory of Open Access Journals (Sweden)

    N. H. Visin

    2010-02-01

    Full Text Available The transitional processes in shunt circuit of traction engines, which armatures and excitation windings are connected in non-conducting direction as to the flowing power current, are considered in this paper. The changes in the control circuits of braking switch and in the shunt power circuit of traction engines with additional mounting a resistor of 0.5 Ohm are proposed. All this modernization will allow increasing greatly the operation reliability of power circuit of ЭР2Т and ЕПЛ2Т electric locomotives during their service life.

  6. Nuclear and global warming issues at a deregulated electricity market

    International Nuclear Information System (INIS)

    Mesarovic, M.

    2001-01-01

    The present challenge is to develop such an energy mix that best supports industrial and societal development and improves the quality of life, while simultaneously minimizing health and environmental impacts. Although two decades ago nuclear was considered to be the energy of the future, it is often overlooked in this context and is now even being questioned in many parts of the world. But, for a world facing increased energy demand and growing concerns about global warming due to the emissions of the 'greenhouse' gasses from burning fossil fuels, nuclear power may become the first priority again, since the nuclear power plants proved to be a reliable and safe source of electricity that produce no greenhouse or acid rain gases, and have already demonstrated their economic competitiveness with alternative generating sources of electrical energy. The competitiveness of nuclear power depends essentially on capital investments which must remain low enough to secure its competitive position. However, nuclear electricity in most countries is less competitive than coal and gas, particularly so after deregulation and liberalization of electricity markets have taken place. In the European Union (EU) there are at present 151 reactor blocks and 68 more in the rest of the European continent. Nuclear power plants in EU currently generate about 35% of electricity, but with the new competitive markets, a major decline in the use of coal is compensated for by an increase in gas because of its lower carbon content, and thus almost all new power stations fully or partially use gas as fuel. However, nuclear power is expected to remain a necessary component of the EU's energy mix for the next 20 years and beyond, and in Central and Eastern Europe it is continuing its growth. While Hungary recently gave up plans to construct two more blocks in its 'Pacs' plant, the Czech government agreed to continue construction of two blocks at its 'Temelin' plant. In Rumania, the second unit of

  7. Functional end-arterial circulation of the choroid assessed by using fat embolism and electric circuit simulation.

    Science.gov (United States)

    Lee, Ji Eun; Ahn, Ki Su; Park, Keun Heung; Pak, Kang Yeun; Kim, Hak Jin; Byon, Ik Soo; Park, Sung Who

    2017-05-30

    The discrepancy in the choroidal circulation between anatomy and function has remained unsolved for several decades. Postmortem cast studies revealed extensive anastomotic channels, but angiographic studies indicated end-arterial circulation. We carried out experimental fat embolism in cats and electric circuit simulation. Perfusion defects were observed in two categories. In the scatter perfusion defects suggesting an embolism at the terminal arterioles, fluorescein dye filled the non-perfused lobule slowly from the adjacent perfused lobule. In the segmental perfusion defects suggesting occlusion of the posterior ciliary arteries, the hypofluorescent segment became perfused by spontaneous resolution of the embolism without subsequent smaller infarction. The angiographic findings could be simulated with an electric circuit. Although electric currents flowed to the disconnected lobule, the level was very low compared with that of the connected ones. The choroid appeared to be composed of multiple sectors with no anastomosis to other sectors, but to have its own anastomotic arterioles in each sector. Blood flows through the continuous choriocapillaris bed in an end-arterial nature functionally to follow a pressure gradient due to the drainage through the collector venule.

  8. System and method to determine electric motor efficiency using an equivalent circuit

    Science.gov (United States)

    Lu, Bin [Kenosha, WI; Habetler, Thomas G [Snellville, GA

    2011-06-07

    A system and method for determining electric motor efficiency includes a monitoring system having a processor programmed to determine efficiency of an electric motor under load while the electric motor is online. The determination of motor efficiency is independent of a rotor speed measurement. Further, the efficiency is based on a determination of stator winding resistance, an input voltage, and an input current. The determination of the stator winding resistance occurs while the electric motor under load is online.

  9. The use of mathematics and electric circuit simulator software in the learning process of wireless power transfer for electrical engineering students

    Science.gov (United States)

    Habibi, Muhammad Afnan; Fall, Cheikh; Setiawan, Eko; Hodaka, Ichijo; Wijono, Hasanah, Rini Nur

    2017-09-01

    Wireless Power Transfer (WPT) isa technique to deliver the electrical power from the source to the load without using wires or conductors. The physics of WPT is well known and basically learned as a course in high school. However, it is very recent that WPT is useful in practical situation: it should be able to transfer electric power in a significant efficiency. It means that WPT requires not much knowledge to university students but may attract students because of cutting edge technique of WPT. On the other hand, phenomena of WPT is invisible and sometimes difficult to imagine. The objective of this paper is to demonstrate the use of mathematics and an electric circuit simulator using MATHEMATICA software and LT-SPICE software in designing a WPT system application. It brings to a conclusion that the students as well the designer can take the benefit of the proposed method. By giving numerical values to circuit parameters, students acquires the power output and efficiency of WPT system. The average power output as well as the efficiency of the designed WPT which resonance frequency set on the system,leads it to produce high output power and better efficiency.

  10. Electronic meter with custom integrated circuit for electric energy measurement; Medidor eletronico de energia eletrica com circuito integrado dedicado

    Energy Technology Data Exchange (ETDEWEB)

    Caldas, Roberto Pereira

    1990-04-01

    The design and implementation of an electrical energy electronic meter for operation at low voltages, according to two steps of development carried out in Centro de Pesquisas de Energia Eletrica - CEPEL is described. In the first step, an electronic meter with discrete commercial components has been developed, in order to demonstrate to the Brazilian power suppliers the feasibility of such a device for electrical energy metering and charging. The second step was constituted by the design of an integrated circuit, aiming the reduction of the cost of the meter as well as the enhancement of its reliability. Several techniques of electrical energy measurement are presented. The meter with discrete components makes use of a time division multiplier (TDM), in order to determine the active power in the load. Voltage and current levels have been reduced through the use of voltage and current sensors compatible with the TDM's inputs. A V-F converter employing continuos integration, has been used for the determination of the energy consumed by the load through the integration of the TDM's output signal. Most of the discrete components of the meter have been replaced by the dedicated integrated circuit. The TDM has remained essentially the same, but the V-F converter has been changed into a dual-slope one, which is more adequate for implementation in a single chip. The tests performed with the prototypes of the meter including both the meter with discrete components and the meter with the custom-made integrated circuit have presented measurement errors of less the 0,2 %. The initial goal, according to Brazilian specifications of electromechanical meters and international specifications for electronic meters, was 1 %. (author)

  11. Electronic meter with custom integrated circuit for electric energy measurement; Medidor eletronico de energia eletrica com circuito integrado dedicado

    Energy Technology Data Exchange (ETDEWEB)

    Caldas, Roberto Pereira

    1990-04-01

    The design and implementation of an electrical energy electronic meter for operation at low voltages, according to two steps of development carried out in Centro de Pesquisas de Energia Eletrica - CEPEL is described. In the first step, an electronic meter with discrete commercial components has been developed, in order to demonstrate to the Brazilian power suppliers the feasibility of such a device for electrical energy metering and charging. The second step was constituted by the design of an integrated circuit, aiming the reduction of the cost of the meter as well as the enhancement of its reliability. Several techniques of electrical energy measurement are presented. The meter with discrete components makes use of a time division multiplier (TDM), in order to determine the active power in the load. Voltage and current levels have been reduced through the use of voltage and current sensors compatible with the TDM's inputs. A V-F converter employing continuos integration, has been used for the determination of the energy consumed by the load through the integration of the TDM's output signal. Most of the discrete components of the meter have been replaced by the dedicated integrated circuit. The TDM has remained essentially the same, but the V-F converter has been changed into a dual-slope one, which is more adequate for implementation in a single chip. The tests performed with the prototypes of the meter including both the meter with discrete components and the meter with the custom-made integrated circuit have presented measurement errors of less the 0,2 %. The initial goal, according to Brazilian specifications of electromechanical meters and international specifications for electronic meters, was 1 %. (author)

  12. Short- circuit tests of circuit breakers

    OpenAIRE

    Chorovský, P.

    2015-01-01

    This paper deals with short-circuit tests of low voltage electrical devices. In the first part of this paper, there are described basic types of short- circuit tests and their principles. Direct and indirect (synthetic) tests with more details are described in the second part. Each test and principles are explained separately. Oscilogram is obtained from short-circuit tests of circuit breakers at laboratory. The aim of this research work is to propose a test circuit for performing indirect test.

  13. Comparison of global storm activity rate calculated from Schumann resonance background components to electric field intensity E0 Z

    Science.gov (United States)

    Nieckarz, Zenon; Kułak, Andrzej; Zięba, Stanisław; Kubicki, Marek; Michnowski, Stanisław; Barański, Piotr

    2009-02-01

    This work presents the results of a comparison between the global storm activity rate IRS and electric field intensity E0 Z. The permanent analysis of the IRS may become an important tool for testing Global Electric Circuit models. IRS is determined by a new method that uses the background component of the first 7 Schumann resonances (SR). The rate calculations are based on ELF observations carried out in 2005 and 2006 in the observatory station "Hylaty" of the Jagiellonian University in the Eastern Carpathians (Kułak, A., Zięba, S., Micek, S., Nieckarz, Z., 2003. Solar variations in extremely low frequency propagation parameters: I. A two-dimensional telegraph equation (TDTE) model of ELF propagation and fundamental parameters of Schumann resonances, J. Geophys. Res., 108, 1270, doi:10.1029/2002JA009304). Diurnal runs of the IRS rate were compared with diurnal runs of E0 Z amplitudes registered at the Earth's surface in the Geophysical Observatory of the Polish Academy of Sciences in Świder (Kubicki, M., 2005. Results of Atmospheric Electricity and Meteorological Observations, S. Kalinowski Geophysical Observatory at Świder 2004, Pub. Inst. Geophysics Polish Academy of Sciences, D-68 (383), Warszawa.). The days with the highest values of the correlation coefficient ( R) between amplitudes of both observed parameters characterizing atmosphere electric activity are shown. The seasonal changes of R, IRS and E0 Z are also presented.

  14. Network model and short circuit program for the Kennedy Space Center electric power distribution system

    Science.gov (United States)

    1976-01-01

    Assumptions made and techniques used in modeling the power network to the 480 volt level are discussed. Basic computational techniques used in the short circuit program are described along with a flow diagram of the program and operational procedures. Procedures for incorporating network changes are included in this user's manual.

  15. Color Coding of Circuit Quantities in Introductory Circuit Analysis Instruction

    Science.gov (United States)

    Reisslein, Jana; Johnson, Amy M.; Reisslein, Martin

    2015-01-01

    Learning the analysis of electrical circuits represented by circuit diagrams is often challenging for novice students. An open research question in electrical circuit analysis instruction is whether color coding of the mathematical symbols (variables) that denote electrical quantities can improve circuit analysis learning. The present study…

  16. Multistage and multiobjective formulations of globally optimal upgradable expansions for electric power distribution systems

    Science.gov (United States)

    Vaziri Yazdi Pin, Mohammad

    Electric power distribution systems are the last high voltage link in the chain of production, transport, and delivery of the electric energy, the fundamental goals of which are to supply the users' demand safely, reliably, and economically. The number circuit miles traversed by distribution feeders in the form of visible overhead or imbedded underground lines, far exceed those of all other bulk transport circuitry in the transmission system. Development and expansion of the distribution systems, similar to other systems, is directly proportional to the growth in demand and requires careful planning. While growth of electric demand has recently slowed through efforts in the area of energy management, the need for a continued expansion seems inevitable for the near future. Distribution system and expansions are also independent of current issues facing both the suppliers and the consumers of electrical energy. For example, deregulation, as an attempt to promote competition by giving more choices to the consumers, while it will impact the suppliers' planning strategies, it cannot limit the demand growth or the system expansion in the global sense. Curiously, despite presence of technological advancements and a 40-year history of contributions in the area, many of the major utilities still relay on experience and resort to rudimentary techniques when planning expansions. A comprehensive literature review of the contributions and careful analyses of the proposed algorithms for distribution expansion, confirmed that the problem is a complex, multistage and multiobjective problem for which a practical solution remains to be developed. In this research, based on the 15-year experience of a utility engineer, the practical expansion problem has been clearly defined and the existing deficiencies in the previous work identified and analyzed. The expansion problem has been formulated as a multistage planning problem in line with a natural course of development and industry

  17. Towards Practical Application of Paper based Printed Circuits: Capillarity Effectively Enhances Conductivity of the Thermoplastic Electrically Conductive Adhesives

    Science.gov (United States)

    Wu, Haoyi; Chiang, Sum Wai; Lin, Wei; Yang, Cheng; Li, Zhuo; Liu, Jingping; Cui, Xiaoya; Kang, Feiyu; Wong, Ching Ping

    2014-09-01

    Direct printing nanoparticle-based conductive inks onto paper substrates has encountered difficulties e.g. the nanoparticles are prone to penetrate into the pores of the paper and become partially segmented, and the necessary low-temperature-sintering process is harmful to the dimension-stability of paper. Here we prototyped the paper-based circuit substrate in combination with printed thermoplastic electrically conductive adhesives (ECA), which takes the advantage of the capillarity of paper and thus both the conductivity and mechanical robustness of the printed circuitsweredrastically improved without sintering process. For instance, the electrical resistivity of the ECA specimen on a pulp paper (6 × 10-5Ω.cm, with 50 wt% loading of Ag) was only 14% of that on PET film than that on PET film. This improvement has been found directly related to the sizing degree of paper, in agreement with the effective medium approximation simulation results in this work. The thermoplastic nature also enables excellent mechanical strength of the printed ECA to resist repeated folding. Considering the generality of the process and the wide acceptance of ECA technique in the modern electronic packages, this method may find vast applications in e.g. circuit boards, capacitive touch pads, and radio frequency identification antennas, which have been prototyped in the manuscript.

  18. A simple electric circuit model for proton exchange membrane fuel cells

    Science.gov (United States)

    Lazarou, Stavros; Pyrgioti, Eleftheria; Alexandridis, Antonio T.

    A simple and novel dynamic circuit model for a proton exchange membrane (PEM) fuel cell suitable for the analysis and design of power systems is presented. The model takes into account phenomena like activation polarization, ohmic polarization, and mass transport effect present in a PEM fuel cell. The proposed circuit model includes three resistors to approach adequately these phenomena; however, since for the PEM dynamic performance connection or disconnection of an additional load is of crucial importance, the proposed model uses two saturable inductors accompanied by an ideal transformer to simulate the double layer charging effect during load step changes. To evaluate the effectiveness of the proposed model its dynamic performance under load step changes is simulated. Experimental results coming from a commercial PEM fuel cell module that uses hydrogen from a pressurized cylinder at the anode and atmospheric oxygen at the cathode, clearly verify the simulation results.

  19. Electric circuit breaker comprising a plurality of vacuum interrupters simultaneously operated by a common operator

    Science.gov (United States)

    Barkan, Philip; Imam, Imdad

    1980-01-01

    This circuit breaker comprises a plurality of a vacuum-type circuit interrupters, each having a movable contact rod. A common operating device for the interrupters comprises a linearly-movable operating member. The interrupters are mounted at one side of the operating member with their movable contact rods extending in a direction generally toward the operating member. Means is provided for mechanically coupling the operating member to the contact rods, and this means comprises a plurality of insulating operating rods, each connected at one end to the operating member and at its opposite end to one of the movable contact rods. The operating rods are of substantially equal length and have longitudinal axes that converge and intersect at substantially a common point.

  20. Student use of model-based reasoning when troubleshooting an electric circuit

    Science.gov (United States)

    Dounas-Frazer, Dimitri

    2016-05-01

    Troubleshooting systems is an integral part of experimental physics in both research and educational settings. Accordingly, ability to troubleshoot is an important learning goal for undergraduate physics lab courses. We investigate students' model-based reasoning on a troubleshooting task using data collected in think-aloud interviews during which pairs of students from two institutions attempted to diagnose and repair a malfunctioning circuit. Our analysis scheme was informed by the Experimental Modeling Framework, which describes physicists' use of mathematical and conceptual models when reasoning about experimental systems. We show that system and subsystem models were crucial for the evaluation of repairs to the circuit and played an important role in some troubleshooting strategies. Finally, drawing on data from interviews with electronics instructors from a broad range of institution types, we outline recommendations for model-based approaches to teaching and learning troubleshooting skills.

  1. Charge Yield at Low Electric Fields: Considerations for Bipolar Integrated Circuits

    Science.gov (United States)

    Johnston, A. H.; Swimm, R. T.; Thorbourn, D. O.

    2013-01-01

    A significant reduction in total dose damage is observed when bipolar integrated circuits are irradiated at low temperature. This can be partially explained by the Onsager theory of recombination, which predicts a strong temperature dependence for charge yield under low-field conditions. Reduced damage occurs for biased as well as unbiased devices because the weak fringing field in thick bipolar oxides only affects charge yield near the Si/SiO2 interface, a relatively small fraction of the total oxide thickness. Lowering the temperature of bipolar ICs - either continuously, or for time periods when they are exposed to high radiation levels - provides an additional degree of freedom to improve total dose performance of bipolar circuits, particularly in space applications.

  2. Non-Contact Circuit for Real-Time Electric and Magnetic Field Measurements

    Science.gov (United States)

    2015-10-01

    response, noise spectral density, and dynamic range. 15. SUBJECT TERMS electric field, magnetic field, 1Wire, low-power microcontroller 16. SECURITY...4 Fig. 4 Altium DesignerTM schematic showing the pin connections of our MSP430 microcontroller ...electrical characteristics of the attached cable. 2. Methods and Procedures The circuit’s primary design consists of a microcontroller , 8-channel digital-to

  3. Electrical Differentiation of Mesenchymal Stem Cells into Schwann-Cell-Like Phenotypes Using Inkjet-Printed Graphene Circuits.

    Science.gov (United States)

    Das, Suprem R; Uz, Metin; Ding, Shaowei; Lentner, Matthew T; Hondred, John A; Cargill, Allison A; Sakaguchi, Donald S; Mallapragada, Surya; Claussen, Jonathan C

    2017-04-01

    Graphene-based materials (GBMs) have displayed tremendous promise for use as neurointerfacial substrates as they enable favorable adhesion, growth, proliferation, spreading, and migration of immobilized cells. This study reports the first case of the differentiation of mesenchymal stem cells (MSCs) into Schwann cell (SC)-like phenotypes through the application of electrical stimuli from a graphene-based electrode. Electrical differentiation of MSCs into SC-like phenotypes is carried out on a flexible, inkjet-printed graphene interdigitated electrode (IDE) circuit that is made highly conductive (sheet resistance electrically stimulated/treated (etMSCs) display significant enhanced cellular differentiation and paracrine activity above conventional chemical treatment strategies [≈85% of the etMSCs differentiated into SC-like phenotypes with ≈80 ng mL -1 of nerve growth factor (NGF) secretion vs. 75% and ≈55 ng mL -1 for chemically treated MSCs (ctMSCs)]. These results help pave the way for in vivo peripheral nerve regeneration where the flexible graphene electrodes could conform to the injury site and provide intimate electrical simulation for nerve cell regrowth. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Circuit modification in electrical field flow fractionation systems generating higher resolution separation of nanoparticles.

    Science.gov (United States)

    Tasci, Tonguc O; Johnson, William P; Fernandez, Diego P; Manangon, Eliana; Gale, Bruce K

    2014-10-24

    Compared to other sub-techniques of field flow fractionation (FFF), cyclical electrical field flow fractionation (CyElFFF) is a relatively new method with many opportunities remaining for improvement. One of the most important limitations of this method is the separation of particles smaller than 100nm. For such small particles, the diffusion rate becomes very high, resulting in severe reductions in the CyElFFF separation efficiency. To address this limitation, we modified the electrical circuitry of the ElFFF system. In all earlier ElFFF reports, electrical power sources have been directly connected to the ElFFF channel electrodes, and no alteration has been made in the electrical circuitry of the system. In this work, by using discrete electrical components, such as resistors and diodes, we improved the effective electric field in the system to allow high resolution separations. By modifying the electrical circuitry of the ElFFF system, high resolution separations of 15 and 40nm gold nanoparticles were achieved. The effects of applying different frequencies, amplitudes and voltage shapes have been investigated and analyzed through experiments. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. Anterior wrist and medial malleolus as the novel sites of tissue selection: a retrospective study on electric shock death through the hand-to-foot circuit pathway.

    Science.gov (United States)

    Xu, Guangtao; Su, Ruibing; Lv, Junyao; Hu, Bo; Gu, Huan; Li, Xianxian; Gu, Jiang; Yu, Xiaojun

    2017-05-01

    Our previous work demonstrated that characteristic changes could occur in the anterior wrist and medial malleolus in electric deaths through the hand-to-foot electric circuit pathway in an electric shock rat model. However, whether the same phenomenon occurs in humans is unknown. The aim of the present retrospective study was to ascertain whether the anterior wrist and medial malleolus could also be selected as the promising and significant sites in electric death through the hand-to-foot circuit pathway. Nineteen human cases from the autopsy and one clinical survivor who sustained a severe electric shock through the hand-to-foot circuit pathway were analyzed. Additional ten autopsy patients who died from traffic accidents and sudden cardiac attacks were used as the control group. Histopathological changes in the soft tissues of the anterior wrist and medial malleolus in all autopsy patients, as well as the electric current pathway of the survivor, were observed. The results showed that the nuclear polarizations in the anterior wrist and medial malleolus soft tissues of the electric death were extremely noticeable as compared with the controls. The most severe electrical injury in the survivor occurred in the anterior wrist. These findings suggest that the soft tissues of the anterior wrist and/or the medial malleolus as the narrowest parts of the limbs could be used as the complementary sites for tissue selection and considered as necessary locations for examinations to assess the electric death in medicolegal identification.

  6. Model-based fault diagnosis approach on external short circuit of lithium-ion battery used in electric vehicles

    International Nuclear Information System (INIS)

    Chen, Zeyu; Xiong, Rui; Tian, Jinpeng; Shang, Xiong; Lu, Jiahuan

    2016-01-01

    Highlights: • The characteristics of ESC fault of lithium-ion battery are investigated experimentally. • The proposed method to simulate the electrical behavior of ESC fault is viable. • Ten parameters in the presented fault model were optimized using a DPSO algorithm. • A two-layer model-based fault diagnosis approach for battery ESC is proposed. • The effective and robustness of the proposed algorithm has been evaluated. - Abstract: This study investigates the external short circuit (ESC) fault characteristics of lithium-ion battery experimentally. An experiment platform is established and the ESC tests are implemented on ten 18650-type lithium cells considering different state-of-charges (SOCs). Based on the experiment results, several efforts have been made. (1) The ESC process can be divided into two periods and the electrical and thermal behaviors within these two periods are analyzed. (2) A modified first-order RC model is employed to simulate the electrical behavior of the lithium cell in the ESC fault process. The model parameters are re-identified by a dynamic-neighborhood particle swarm optimization algorithm. (3) A two-layer model-based ESC fault diagnosis algorithm is proposed. The first layer conducts preliminary fault detection and the second layer gives a precise model-based diagnosis. Four new cells are short-circuited to evaluate the proposed algorithm. It shows that the ESC fault can be diagnosed within 5 s, the error between the model and measured data is less than 0.36 V. The effectiveness of the fault diagnosis algorithm is not sensitive to the precision of battery SOC. The proposed algorithm can still make the correct diagnosis even if there is 10% error in SOC estimation.

  7. Single cell wound generates electric current circuit and cell membrane potential variations that requires calcium influx.

    Science.gov (United States)

    Luxardi, Guillaume; Reid, Brian; Maillard, Pauline; Zhao, Min

    2014-07-24

    Breaching of the cell membrane is one of the earliest and most common causes of cell injury, tissue damage, and disease. If the compromise in cell membrane is not repaired quickly, irreversible cell damage, cell death and defective organ functions will result. It is therefore fundamentally important to efficiently repair damage to the cell membrane. While the molecular aspects of single cell wound healing are starting to be deciphered, its bio-physical counterpart has been poorly investigated. Using Xenopus laevis oocytes as a model for single cell wound healing, we describe the temporal and spatial dynamics of the wound electric current circuitry and the temporal dynamics of cell membrane potential variation. In addition, we show the role of calcium influx in controlling electric current circuitry and cell membrane potential variations. (i) Upon wounding a single cell: an inward electric current appears at the wound center while an outward electric current is observed at its sides, illustrating the wound electric current circuitry; the cell membrane is depolarized; calcium flows into the cell. (ii) During cell membrane re-sealing: the wound center current density is maintained for a few minutes before decreasing; the cell membrane gradually re-polarizes; calcium flow into the cell drops. (iii) In conclusion, calcium influx is required for the formation and maintenance of the wound electric current circuitry, for cell membrane re-polarization and for wound healing.

  8. High speed hydraulically-actuated operating system for an electric circuit breaker

    Science.gov (United States)

    Iman, Imdad

    1983-06-07

    This hydraulically-actuated operating system comprises a cylinder, a piston movable therein in an opening direction to open a circuit breaker, and an accumulator for supplying pressurized liquid to a breaker-opening piston-actuating space within the cylinder. A normally-closed valve between the accumulator and the actuating space is openable to allow pressurized liquid from the accumulator to flow through the valve into the actuating space to drive the piston in an opening direction. A dashpotting mechanism operating separately from the hydraulic actuating system is provided, thereby reducing flow restriction interference with breaker opening.

  9. Feasibility study of superconducting power cables for DC electric railway feeding systems in view of thermal condition at short circuit accident

    Science.gov (United States)

    Kumagai, Daisuke; Ohsaki, Hiroyuki; Tomita, Masaru

    2016-12-01

    A superconducting power cable has merits of a high power transmission capacity, transmission losses reduction, a compactness, etc., therefore, we have been studying the feasibility of applying superconducting power cables to DC electric railway feeding systems. However, a superconducting power cable is required to be cooled down and kept at a very low temperature, so it is important to reveal its thermal and cooling characteristics. In this study, electric circuit analysis models of the system and thermal analysis models of superconducting cables were constructed and the system behaviors were simulated. We analyzed the heat generation by a short circuit accident and transient temperature distribution of the cable to estimate the value of temperature rise and the time required from the accident. From these results, we discussed a feasibility of superconducting cables for DC electric railway feeding systems. The results showed that the short circuit accident had little impact on the thermal condition of a superconducting cable in the installed system.

  10. Experimental verification of a thermal equivalent circuit dynamic model on an extended range electric vehicle battery pack

    Science.gov (United States)

    Ramotar, Lokendra; Rohrauer, Greg L.; Filion, Ryan; MacDonald, Kathryn

    2017-03-01

    The development of a dynamic thermal battery model for hybrid and electric vehicles is realized. A thermal equivalent circuit model is created which aims to capture and understand the heat propagation from the cells through the entire pack and to the environment using a production vehicle battery pack for model validation. The inclusion of production hardware and the liquid battery thermal management system components into the model considers physical and geometric properties to calculate thermal resistances of components (conduction, convection and radiation) along with their associated heat capacity. Various heat sources/sinks comprise the remaining model elements. Analog equivalent circuit simulations using PSpice are compared to experimental results to validate internal temperature nodes and heat rates measured through various elements, which are then employed to refine the model further. Agreement with experimental results indicates the proposed method allows for a comprehensive real-time battery pack analysis at little computational expense when compared to other types of computer based simulations. Elevated road and ambient conditions in Mesa, Arizona are simulated on a parked vehicle with varying quiescent cooling rates to examine the effect on the diurnal battery temperature for longer term static exposure. A typical daily driving schedule is also simulated and examined.

  11. All-metallic electrically gated 2H-TaSe2 thin-film switches and logic circuits

    International Nuclear Information System (INIS)

    Renteria, J.; Jiang, C.; Yan, Z.; Samnakay, R.; Goli, P.; Pope, T. R.; Salguero, T. T.; Wickramaratne, D.; Lake, R. K.; Khitun, A. G.; Balandin, A. A.

    2014-01-01

    We report the fabrication and performance of all-metallic three-terminal devices with tantalum diselenide thin-film conducting channels. For this proof-of-concept demonstration, the layers of 2H-TaSe 2 were exfoliated mechanically from single crystals grown by the chemical vapor transport method. Devices with nanometer-scale thicknesses exhibit strongly non-linear current-voltage characteristics, unusual optical response, and electrical gating at room temperature. We have found that the drain-source current in thin-film 2H-TaSe 2 –Ti/Au devices reproducibly shows an abrupt transition from a highly resistive to a conductive state, with the threshold tunable via the gate voltage. Such current-voltage characteristics can be used, in principle, for implementing radiation-hard all-metallic logic circuits. These results may open new application space for thin films of van der Waals materials

  12. All-metallic electrically gated 2H-TaSe2 thin-film switches and logic circuits

    Science.gov (United States)

    Renteria, J.; Samnakay, R.; Jiang, C.; Pope, T. R.; Goli, P.; Yan, Z.; Wickramaratne, D.; Salguero, T. T.; Khitun, A. G.; Lake, R. K.; Balandin, A. A.

    2014-01-01

    We report the fabrication and performance of all-metallic three-terminal devices with tantalum diselenide thin-film conducting channels. For this proof-of-concept demonstration, the layers of 2H-TaSe2 were exfoliated mechanically from single crystals grown by the chemical vapor transport method. Devices with nanometer-scale thicknesses exhibit strongly non-linear current-voltage characteristics, unusual optical response, and electrical gating at room temperature. We have found that the drain-source current in thin-film 2H-TaSe2-Ti/Au devices reproducibly shows an abrupt transition from a highly resistive to a conductive state, with the threshold tunable via the gate voltage. Such current-voltage characteristics can be used, in principle, for implementing radiation-hard all-metallic logic circuits. These results may open new application space for thin films of van der Waals materials.

  13. All-metallic electrically gated 2H-TaSe{sub 2} thin-film switches and logic circuits

    Energy Technology Data Exchange (ETDEWEB)

    Renteria, J.; Jiang, C.; Yan, Z. [Nano-Device Laboratory, Department of Electrical Engineering, Bourns College of Engineering, University of California–Riverside, Riverside, California 92521 (United States); Samnakay, R.; Goli, P. [Materials Science and Engineering Program, Bourns College of Engineering, University of California–Riverside, Riverside, California 92521 (United States); Pope, T. R.; Salguero, T. T. [Department of Chemistry, University of Georgia, Athens, Georgia 30602 (United States); Wickramaratne, D.; Lake, R. K. [Laboratory for Terascale and Terahertz Electronics, Department of Electrical Engineering, Bourns College of Engineering, University of California–Riverside, Riverside, California 92521 (United States); Khitun, A. G. [Nano-Device Laboratory, Department of Electrical Engineering, Bourns College of Engineering, University of California–Riverside, Riverside, California 92521 (United States); Materials Science and Engineering Program, Bourns College of Engineering, University of California–Riverside, Riverside, California 92521 (United States); Balandin, A. A., E-mail: balandin@ee.ucr.edu [Nano-Device Laboratory, Department of Electrical Engineering, Bourns College of Engineering, University of California–Riverside, Riverside, California 92521 (United States); Department of Chemistry, University of Georgia, Athens, Georgia 30602 (United States)

    2014-01-21

    We report the fabrication and performance of all-metallic three-terminal devices with tantalum diselenide thin-film conducting channels. For this proof-of-concept demonstration, the layers of 2H-TaSe{sub 2} were exfoliated mechanically from single crystals grown by the chemical vapor transport method. Devices with nanometer-scale thicknesses exhibit strongly non-linear current-voltage characteristics, unusual optical response, and electrical gating at room temperature. We have found that the drain-source current in thin-film 2H-TaSe{sub 2}–Ti/Au devices reproducibly shows an abrupt transition from a highly resistive to a conductive state, with the threshold tunable via the gate voltage. Such current-voltage characteristics can be used, in principle, for implementing radiation-hard all-metallic logic circuits. These results may open new application space for thin films of van der Waals materials.

  14. Thermoelectric cooling of microelectronic circuits and waste heat electrical power generation in a desktop personal computer

    International Nuclear Information System (INIS)

    Gould, C.A.; Shammas, N.Y.A.; Grainger, S.; Taylor, I.

    2011-01-01

    Thermoelectric cooling and micro-power generation from waste heat within a standard desktop computer has been demonstrated. A thermoelectric test system has been designed and constructed, with typical test results presented for thermoelectric cooling and micro-power generation when the computer is executing a number of different applications. A thermoelectric module, operating as a heat pump, can lower the operating temperature of the computer's microprocessor and graphics processor to temperatures below ambient conditions. A small amount of electrical power, typically in the micro-watt or milli-watt range, can be generated by a thermoelectric module attached to the outside of the computer's standard heat sink assembly, when a secondary heat sink is attached to the other side of the thermoelectric module. Maximum electrical power can be generated by the thermoelectric module when a water cooled heat sink is used as the secondary heat sink, as this produces the greatest temperature difference between both sides of the module.

  15. Fusion power in a future low carbon global electricity system

    DEFF Research Database (Denmark)

    Cabal, H.; Lechón, Y.; Bustreo, C.

    2017-01-01

    Fusion is one of the technologies that may contribute to a future, low carbon, global energy supply system. In this article we investigate the role that it may play under different scenarios. The global energy model ETM (originally EFDA TIMES Model) has been used to analyse the participation...

  16. The Materialist Circuits and the Quest for Environmental Justice in ICT’s Global Expansion

    Directory of Open Access Journals (Sweden)

    Sibo Chen

    2016-02-01

    Full Text Available This article builds on and contributes to research on the material impacts of Information and Communication Technology and Consumer Electronics (ICT/CE by proposing a holistic framework addressing labour exploitation and environmental destruction in the production, consumption, and disposal of digital devices. Although the emerging media scholarship on digital labour have critically analyzed the material impacts of ICT/CE in terms of labour issues emerged from the production and consumption stages, relatively little research attention has been paid to the end-of-life issues of digital devices and other environmental issues caused by the ICT industry’s global expansion. Based upon previous research on digital labour, environmental management and ecological justice, this article proposes a political economic understanding of the environmental dimension of the ICT industry and how it has contributed to the escalation of environmental crisis and social injustice in developing coun-tries, especially in terms of the urging situation of the global e-waste challenge. The article argues that the critical standpoints taken by political economy of communication and environmental justice re-search provide valuable and promising theoretical connections between labour activism and ecological struggles; and future inquiries on digital economy, in this regard, should combine both perspectives, pay more attention to the enormous social and ecological tensions in the Global South, and make explicit connections between the regressions in labour rights and global environmental justice and ICT’s aggressive and unsustainable expansion.

  17. IE Information Notice No. 85-93: Westinghouse Type DS circuit breakers, potential failure of electric closing feature because of broken spring release latch lever

    International Nuclear Information System (INIS)

    Jordan, E.L.

    1992-01-01

    On April 14, 1985, the Westinghouse Nuclear Services Integration Division (NSID) issued Technical Bulletin No. NSID-TB-85-17 advising their customers of a potential malfunction in Westinghouse Type DS Class 1E circuit breakers because of broken spring release latch levers. These electrically operated type DS breakers will not close electrically when the spring release latch lever has been broken off. Twenty-five broken levers have been reported and evaluated. This evaluation shows concentrations of incidents traceable to manufacturing in the following periods of time: early 1975, April 1976, and early 1978. This circuit breaker failure, as discussed, adversely affects the safety function (closing on demand) when the circuit breaker is used in the Engineered Safety Features Systems. However, this failure mode will not affect the safety trip function when it is used in the reactor protection system

  18. Equatorial electrojet as part of the global circuit: a case-study from the IEEY

    Directory of Open Access Journals (Sweden)

    A. T. Kobea

    1998-06-01

    Full Text Available Geomagnetic storm-time variations often occur coherently at high latitude and the day-side dip equator where they affect the normal eastward Sq field. This paper presents an analysis of ground magnetic field and ionospheric electrodynamic data related to the geomagnetic storm which occured on 27 May 1993 during the International Equatorial Electrojet Year (IEEY experiment. This storm-signature analysis on the auroral, mid-latitude and equatorial ground field and ionospheric electrodynamic data leads to the identification of a sensitive response of the equatorial electrojet (EEJ to large-scale auroral return current: this response consists in a change of the eastward electric field during the pre-sunrise hours (0400-0600 UT coherently to the high-, mid-, and equatorial-latitude H decrease and the disappearance of the EEJ irregularities between the time-interval 0800-0950 UT. Subsequent to the change in h'F during pre-sunrise hours, the observed foF2 increase revealed an enhancement of the equatorial ionization anomaly (EIA caused by the high-latitude penetrating electric field. The strengthening of these irregularities attested by the Doppler frequency increase tracks the H component at the equator which undergoes a rapid increase around 0800 UT. The ∆H variations observed at the equator are the sum of the following components: SR, DP, DR, DCF and DT.Keywords. Equatorial electrojet · Magnetosphere-ionosphere interactions · Electric fields and currents · Auroral ionosphere · Ionospheric disturbances

  19. Do Skilled Elementary Teachers Hold Scientific Conceptions and Can They Accurately Predict the Type and Source of Students' Preconceptions of Electric Circuits?

    Science.gov (United States)

    Lin, Jing-Wen

    2016-01-01

    Holding scientific conceptions and having the ability to accurately predict students' preconceptions are a prerequisite for science teachers to design appropriate constructivist-oriented learning experiences. This study explored the types and sources of students' preconceptions of electric circuits. First, 438 grade 3 (9 years old) students were…

  20. Military Curricula for Vocational & Technical Education. Basic Electricity and Electronics Individualized Learning System. CANTRAC A-100-0010. Module Fourteen: Parallel AC Resistive-Reactive Circuits. Study Booklet.

    Science.gov (United States)

    Chief of Naval Education and Training Support, Pensacola, FL.

    This individualized learning module on parallel alternating current resistive-reaction circuits is one in a series of modules for a course in basic electricity and electronics. The course is one of a number of military-developed curriculum packages selected for adaptation to vocational instructional and curriculum development in a civilian…

  1. Military Curricula for Vocational & Technical Education. Basic Electricity and Electronics Individualized Learning System. CANTRAC A-100-0010. Module Six: Parallel Circuits. Study Booklet.

    Science.gov (United States)

    Chief of Naval Education and Training Support, Pensacola, FL.

    This individualized learning module on parallel circuits is one in a series of modules for a course in basic electricity and electronics. The course is one of a number of military-developed curriculum packages selected for adaptation to vocational instructional and curriculum development in a civilian setting. Four lessons are included in the…

  2. Military Curricula for Vocational & Technical Education. Basic Electricity and Electronics. CANTRAC A-100-0010. Module 34: Linear Integrated Circuits. Study Booklet.

    Science.gov (United States)

    Chief of Naval Education and Training Support, Pensacola, FL.

    This individualized learning module on linear integrated circuits is one in a series of modules for a course in basic electricity and electronics. The course is one of a number of military-developed curriculum packages selected for adaptation to vocational instructional and curriculum development in a civilian setting. Two lessons are included in…

  3. MATHEMATICAL MODELING OF TRANSIENT EMERGENCY ELECTROMAGNETIC PROCESSES IN THE SYSTEM OF THE ELECTROMAGNETIC TRACTION DC. 2. SHORT CIRCUIT WITH ELECTRIC ROLLING STOCK

    Directory of Open Access Journals (Sweden)

    P. E. Mihalichenko

    2010-04-01

    Full Text Available The article deals with the description of mathematical model of the system of traction electric power supply with load in the short circuit condition as well as the calculation results of this emergency process. The transition values as well as the character of their change, which can be used for detection of emergency processes, have been determined.

  4. Room Temperature Magnetic Field Measurements as a Tool to Localize Inter-turns Electrical Short Circuits in the LHC Main Dipole coils

    CERN Document Server

    Bellesia, B; Todesco, E

    2006-01-01

    In this report the method for the localization of the electric shorts circuits in the main LHC dipoles using the magnetic measurements at room temperature is presented. The steps of the method are discussed, and two cases are studied in detail. A complete statistics of the 12 cases analyzed up to now is given.

  5. Calculation of cooling internal circuits loss of load curve in giant electric machines; Calculo da curva de perda de carga dos circuitos axiais internos de refrigeracao de maquinas eletricas gigantes

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Hilton Penha [Parana Univ., Curitiba, PR (Brazil). Dept. de Engenharia Mecanica. Dept. de Engenharia do Produto; Passos, Alex Sandro Barbosa [Parana Univ., Curitiba, PR (Brazil). Dept. de Engenharia Mecanica. Dept. de Pesquisa e Desenvolvimento do Produto

    2001-07-01

    This article describes a method for calculation of the loss of load curve for the ventilation axial circuits. The method assumes the ventilation circuit representation in a way similar to the electrical circuits. The great difficulty of circuit solution resides in the non linearity of the loss of load resistances and the equations relating the pressures and flows. The method is based on the association of the resistance curves of loss of load in a such way that, when the resistance curve of the total circuit loss of load is obtained, the blower operation point can be easily obtained and, consequently, the individual flows for each section of the circuit.

  6. Exploring the Technological Collaboration Characteristics of the Global Integrated Circuit Manufacturing Industry

    Directory of Open Access Journals (Sweden)

    Yun Liu

    2018-01-01

    Full Text Available With the intensification of international competition, there are many international technological collaborations in the integrated circuit manufacturing (ICM industry. The importance of improving the level of international technological collaboration is becoming more and more prominent. Therefore, it is vital for a country, a region, or an institution to understand the international technological collaboration characteristics of the ICM industry and, thus, to know how to enhance its own international technological collaboration. This paper depicts the international technological collaboration characteristics of the ICM industry based on patent analysis. Four aspects, which include collaboration patterns, collaboration networks, collaboration institutions, and collaboration impacts, are analyzed by utilizing patent association analysis and social network analysis. The findings include the following: first, in regard to international technological collaboration, the USA has the highest level, while Germany has great potential for future development; second, Asia and Europe have already formed clusters, respectively, in the cooperative network; last, but not least, research institutions, colleges, and universities should also actively participate in international collaboration. In general, this study provides an objective reference for policy making, competitiveness, and sustainability in the ICM industry. The framework presented in this paper could be applied to examine other industrial international technological collaborations.

  7. Does Global Astrocytic Calcium Signaling Participate in Awake Brain State Transitions and Neuronal Circuit Function?

    DEFF Research Database (Denmark)

    Kjaerby, Celia; Rasmussen, Rune; Andersen, Mie

    2017-01-01

    of the neuromodulators, noradrenaline and acetylcholine. Astrocytes have emerged as a new player participating in the regulation of brain activity, and have recently been implicated in brain state shifts. Astrocytes display global Ca(2+) signaling in response to activation of the noradrenergic system, but whether...... astrocytic Ca(2+) signaling is causative or correlative for shifts in brain state and neural activity patterns is not known. Here we review the current available literature on astrocytic Ca(2+) signaling in awake animals in order to explore the role of astrocytic signaling in brain state shifts. Furthermore......We continuously need to adapt to changing conditions within our surrounding environment, and our brain needs to quickly shift between resting and working activity states in order to allow appropriate behaviors. These global state shifts are intimately linked to the brain-wide release...

  8. Closing of water circuits – a global benchmark on sustainable water management

    Directory of Open Access Journals (Sweden)

    Fröhlich Siegmund

    2017-01-01

    Full Text Available Access to clean water resources has always been a crucial factor in the history of mankind. Now, in the 21st century, water, as an increasingly scarce resource, will take a strategic role for the future development of global populations. As the former UN Secretary General Dr. Dr. Boutrous Boutrous Ghali predicts: “The wars of the 21st century will be fought not over oil, they will be fought over water.” [1]. In nine global examples will be demonstrated the different ways of dealing with water resources. That are: Mexico City, Egypt, Libya, DOW Terneuzen, Los Angeles, Israel, China and Singapore and also global trends, such as, scarcity & rural exodus and salinization of soil. Thereby, he explains the different kinds of water management to be observed. The most relevant prognosis of the WHO is, that to the end of 21st century Africa's population will grow over proportionally from 1 billion now up to nearly 4 billion [9]. That is why all efforts need to be concentrated on helping Africa create a sustainable economic development. The first and by far most important strategic step is to assure access to clean water resources in the rural and mostly arid regions of the continent. The lecturer shows several technological proposals on how to overcame problems like: water scarcity, rural exodus, salinization of soil and others. Such technologies could be successfully implemented in sustainable development programs in African countries.

  9. Closing of water circuits - a global benchmark on sustainable water management

    Science.gov (United States)

    Fröhlich, Siegmund

    2017-11-01

    Access to clean water resources has always been a crucial factor in the history of mankind. Now, in the 21st century, water, as an increasingly scarce resource, will take a strategic role for the future development of global populations. As the former UN Secretary General Dr. Dr. Boutrous Boutrous Ghali predicts: "The wars of the 21st century will be fought not over oil, they will be fought over water." [1]. In nine global examples will be demonstrated the different ways of dealing with water resources. That are: Mexico City, Egypt, Libya, DOW Terneuzen, Los Angeles, Israel, China and Singapore and also global trends, such as, scarcity & rural exodus and salinization of soil. Thereby, he explains the different kinds of water management to be observed. The most relevant prognosis of the WHO is, that to the end of 21st century Africa's population will grow over proportionally from 1 billion now up to nearly 4 billion [9]. That is why all efforts need to be concentrated on helping Africa create a sustainable economic development. The first and by far most important strategic step is to assure access to clean water resources in the rural and mostly arid regions of the continent. The lecturer shows several technological proposals on how to overcame problems like: water scarcity, rural exodus, salinization of soil and others. Such technologies could be successfully implemented in sustainable development programs in African countries.

  10. One watt initiative: A global effort to reduce leaking electricity

    International Nuclear Information System (INIS)

    Meier, Alan K.; LeBot, Benoit

    1999-01-01

    Many domestic appliances and commercial equipment consume some electric power when they are switched off or not performing their primary purpose. The typical loss per appliance is low (from 1 to 25 W) but, when multiplied by the billions of appliances in houses and in commercial buildings, standby losses represent a significant fraction of total electricity use. Several initiatives to reduce standby losses have appeared in different parts of the world. One proposal, the 1-watt plan, seeks to harmonize these initiatives by establishing a single target for all appliances. This paper explains the background to the 1-watt plan, identifies some unresolved aspects, and gives some estimates of energy savings

  11. Equatorial electrojet as part of the global circuit: a case-study from the IEEY

    Directory of Open Access Journals (Sweden)

    A. T. Kobea

    Full Text Available Geomagnetic storm-time variations often occur coherently at high latitude and the day-side dip equator where they affect the normal eastward Sq field. This paper presents an analysis of ground magnetic field and ionospheric electrodynamic data related to the geomagnetic storm which occured on 27 May 1993 during the International Equatorial Electrojet Year (IEEY experiment. This storm-signature analysis on the auroral, mid-latitude and equatorial ground field and ionospheric electrodynamic data leads to the identification of a sensitive response of the equatorial electrojet (EEJ to large-scale auroral return current: this response consists in a change of the eastward electric field during the pre-sunrise hours (0400-0600 UT coherently to the high-, mid-, and equatorial-latitude H decrease and the disappearance of the EEJ irregularities between the time-interval 0800-0950 UT. Subsequent to the change in h'F during pre-sunrise hours, the observed foF2 increase revealed an enhancement of the equatorial ionization anomaly (EIA caused by the high-latitude penetrating electric field. The strengthening of these irregularities attested by the Doppler frequency increase tracks the H component at the equator which undergoes a rapid increase around 0800 UT. The ∆H variations observed at the equator are the sum of the following components: SR, DP, DR, DCF and DT.

    Keywords. Equatorial electrojet · Magnetosphere-ionosphere interactions · Electric fields and currents · Auroral ionosphere · Ionospheric disturbances

  12. NRC Information No. 89-63: Possible submergence of electrical circuits located above the flood level because of water intrusion and lack of drainage

    International Nuclear Information System (INIS)

    Rossi, C.E.

    1992-01-01

    This information notice is being provided to alert addressees that electrical circuits located above the plant flood level within electrical enclosures may become submerged in water because appropriate drainage has not been provided. Failure of electrical circuits during service conditions, including postulated accidents, can occur due to submergence if water enters these enclosures and there is no provision for drainage. The electrical enclosures addressed by this notice include terminal boxes, junction boxes, pull boxes, conduits, Condulets, and other enclosures for end-use equipment (such as limit switches, motor operators, and electrical penetrations), the contents of which may include cables, terminal blocks, electrical splices and connectors. Information Notice 84-57, ''Operating Experience Related to Moisture Intrusion on Safety-Related Electrical Equipment at Commercial Power Plants,'' addressed watertight sealing of all electrical conduits to junction boxes and conduit-to-terminal box connection points for safety-related equipment located in areas of the reactor building as well as for areas that are potentially subject to high temperature steam or water impingement. This notice further addressed the importance of ensuring that box drain holes and equipment interfaces are in conformance with the test setup established during equipment qualification testing and with the vendor's recommendations

  13. Cellular and circuit properties supporting different sensory coding strategies in electric fish and other systems.

    Science.gov (United States)

    Marsat, Gary; Longtin, André; Maler, Leonard

    2012-08-01

    Neural codes often seem tailored to the type of information they must carry. Here we contrast the encoding strategies for two different communication signals in electric fish and describe the underlying cellular and network properties that implement them. We compare an aggressive signal that needs to be quickly detected, to a courtship signal whose quality needs to be evaluated. The aggressive signal is encoded by synchronized bursts and a predictive feedback input is crucial in separating background noise from the communication signal. The courtship signal is accurately encoded through a heterogenous population response allowing the discrimination of signal differences. Most importantly we show that the same strategies are used in other systems arguing that they evolved similar solutions because they faced similar tasks. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. A bidirectional soft switched ultracapacitor interface circuit for hybrid electric vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Farzanehfard, Hosein; Beyragh, Dawood Shekari; Adib, Ehsan [Electrical and Computer Engineering Department, Isfahan University of Technology, Isfahan 84156 (Iran)

    2008-12-15

    Ultracapacitors are used as auxiliary elements beside batteries to increase peak power capability and battery life in hybrid electric vehicles. In such a configuration, a bidirectional high efficiency converter is required as an interface between ultracapacitors and batteries. Since the voltage level of ultracapacitors and batteries are different, the interface must be able to increase or decrease the voltage level in each power flow direction while limiting the current. This paper presents a zero voltage transition (ZVT) buck-and-boost converter for ultracapacitors interface. All the switches in the proposed converter are soft switched to reduce switching losses and increase efficiency. The converter operational modes are analyzed and its performance is discussed. Finally, the experimental results from a 150 W laboratory prototype are presented which justify the theoretical analysis. (author)

  15. Electric circuit modeling of lithium-sulfur batteries during discharging state

    DEFF Research Database (Denmark)

    Stroe, Daniel-Ioan; Knap, Vaclav; Swierczynski, Maciej Jozef

    2017-01-01

    Lithium-ion batteries are characterized by having very good performance in terms of efficiency, lifetime, and selfdischarge, which allowed them to become the major player in the electric vehicle applications. However, they were not able to totally overcome the EV range anxiety. Thus, research...... is carried out nowadays to develop batteries with even higher gravimetric energy density, which should allow a substantial range increase. One of the technologies, which should be able to meet the range requirements is the Lithium-Sulfur (Li-S) battery. Thanks to the extensive research and development...... static and pulse discharge profiles, showing a good accuracy in predicting the voltage of the tested Li-S battery cell....

  16. Global long-term cost dynamics of offshore wind electricity generation

    NARCIS (Netherlands)

    Gernaat, David E H J; Van Vuuren, Detlef P.; Van Vliet, Jasper; Sullivan, Patrick; Arent, Douglas J.

    2014-01-01

    Using the IMAGE/TIMER (The Targets IMage Energy Regional) long-term integrated assessment model, this paper explores the regional and global potential of offshore wind to contribute to global electricity production. We develop long-term cost supply curve for offshore wind, a representation of the

  17. 'Gatekeepers' of Islamic financial circuits: analysing urban geographies of the global Shari'a elite

    OpenAIRE

    Bassens, David; Derudder, Ben; Witlox, Frank

    2012-01-01

    This paper analyses the importance of 'Shari'a scholars' in the Islamic Financial Services (IFS) sector, which has been a growing global practice since the 1970s. Based on Shari'a Law, IFS firms provide banking, finance and insurance respecting faith-based prohibitions on interest, speculation and risk taking. Although IFS firms operate across a variety of scales and involve a range of actors, this paper focuses on the transnational capacities of Shari'a experts employed by IFS firms. These s...

  18. Experimental Device for Learning of Logical Circuit Design using Integrated Circuits

    OpenAIRE

    石橋, 孝昭

    2012-01-01

    This paper presents an experimental device for learning of logical circuit design using integrated circuits and breadboards. The experimental device can be made at a low cost and can be used for many subjects such as logical circuits, computer engineering, basic electricity, electrical circuits and electronic circuits. The proposed device is effective to learn the logical circuits than the usual lecture.

  19. Hydropower's future, the environment, and global electricity systems

    Energy Technology Data Exchange (ETDEWEB)

    Sternberg, R. [Department of Earth and Environmental Studies, Montclair State University, 1 Normal Ave, Montclair, NJ 07043-1624 (United States)

    2010-02-15

    Hydropower is a well established electricity system on the global scene. Global electricity needs by far exceed the amount of electricity that hydrosystems can provide to meet global electricity needs. Much of the world's hydropower remains to be brought into production. Improved technology, better calibrated environmental parameters for large projects have become the norm in the past 15 years. How and why does hydropower retain a prominent role in electricity production? How and why does hydropower find social acceptance in diverse social systems? How does hydropower project planning address issues beyond electricity generation? How does the systems approach to hydropower installations further analysis of comparative energy sources powering electricity systems? Attention to the environmental impact of hydropower facilities forms an integral part of systems analysis. Similarly, the technical, political and economic variables call for balanced analysis to identify the viability status of hydro projects. Economic competition among energy systems requires in context assessments as these shape decision making in planning of hydropower systems. Moreover, technological change has to be given a time frame during which the sector advances in productivity and share in expanding electricity generation. The low production costs per kWh assure hydropower at this juncture, 2009, a very viable future. (author)

  20. Transient behavior of redox flow battery connected to circuit based on global phase structure

    Science.gov (United States)

    Mannari, Toko; Hikihara, Takashi

    A Redox Flow Battery (RFB) is one of the promising energy storage systems in power grid. An RFB has many advantages such as a quick response, a large capacity, and a scalability. Due to these advantages, an RFB can operate in mixed time scale. Actually, it has been demonstrated that an RFB can be used for load leveling, compensating sag, and smoothing the output of the renewable sources. An analysis on transient behaviors of an RFB is a key issue for these applications. An RFB is governed by electrical, chemical, and fluid dynamics. The hybrid structure makes the analysis difficult. To analyze transient behaviors of an RFB, the exact model is necessary. In this paper, we focus on a change in a concentration of ions in the electrolyte, and simulate the change with a model which is mainly based on chemical kinetics. The simulation results introduces transient behaviors of an RFB in a response to a load variation. There are found three kinds of typical transient behaviors including oscillations. As results, it is clarified that the complex transient behaviors, due to slow and fast dynamics in the system, arise by the quick response to load.

  1. Modeling and interpretation of electrical impedance spectra of dye solar cells operated under open-circuit conditions

    International Nuclear Information System (INIS)

    Kern, R.; Sastrawan, R.; Ferber, J.; Stangl, R.; Luther, J.

    2002-01-01

    Electrical impedance spectroscopy (EIS) was applied in order to investigate electrochemical nanocrystalline TiO 2 dye solar cells (DSC). Typically, three characteristic frequency peaks were observed in the spectra. These frequency peaks could be explained by variations of cell parameters and by comparison with intensity-modulated photovoltage spectroscopy (IMVS). It was shown that the low-frequency peak (in the mHz range) corresponds to the Nernstian diffusion within the electrolyte, while the middle-frequency peak (in the 10-100 Hz range) reflects the properties of the photoinjected electrons within the TiO 2 . The high-frequency peak (in the kHz range) corresponds to the charge-transfer at the platinum counter electrode. For a detailed analysis of the spectra, a model was developed which allows the evaluation of EIS spectra, measured under bias illumination and under open-circuit conditions. The influence of cell parameters such as the TiO 2 layer thickness, cell thickness, charge-transfer resistance of the platinum counter electrode, and the lifetime of the photoinjected electrons, on the impedance spectra was studied both experimentally and theoretically. Finally, it is shown that EIS is a measurement method suited well for the investigation of the long-term stability of DSC, as changes of the inner cell parameters can be revealed

  2. Learning Electrical Circuits: The Effects of the 4C-ID Instructional Approach in the Acquisition and Transfer of Knowledge

    Directory of Open Access Journals (Sweden)

    Mario Melo

    2015-07-01

    Full Text Available This study was designed to investigate the effects of two instructional approaches (4C-ID versus conventional on learners’ knowledge-acquisition and learning transfer of the electrical circuits content in Physics. Participants were 129 9th graders from a secondary school in Lisbon, M = 14.3 years, SD = 0.54. The participants were divided in two groups: an experimental group constituted three intact classes (n = 78; and a control group constituted two intact classes (n = 51. The experimental group was taught using a digital learning environment designed with the 4C-ID model principles while the control group learned the same contents through a conventional method. We assessed the students’ performance (knowledge-acquisition and transfer, the perceived cognitive load, and the instructional efficiency. Results indicated that the experimental group performed significantly better than the control group on a knowledge-acquisition test and in a learning transfer test. They also perceived a less cognitive load in the transfer test and the learning environment developed with the 4C-ID model proved to be more instructional efficient than the conventional method.

  3. An Examination of AC/HVDC Power Circuits for Interconnecting Bulk Wind Generation with the Electric Grid

    Directory of Open Access Journals (Sweden)

    Daniel Ludois

    2010-06-01

    Full Text Available The application of high voltage dc (HVDC transmission for integrating large scale and/or off-shore wind generation systems with the electric grid is attractive in comparison to extra high voltage (EHV ac transmission due to a variety of reasons. While the technology of classical current sourced converters (CSC using thyristors is well established for realization of large HVDC systems, the technology of voltage sourced converters (VSC is emerging to be an alternative approach, particularly suitable for multi-terminal interconnections. More recently, a more modular scheme that may be termed ‘bridge of bridge’ converters (BoBC has been introduced to realize HVDC systems. While all these three approaches are functionally capable of realizing HVDC systems, the converter power circuit design trade-offs between these alternatives are not readily apparent. This paper presents an examination of these topologies from the point of view of power semiconductor requirements, reactive component requirements, operating losses, fault tolerance, multi-terminal operation, modularity, complexity, etc. Detailed analytical models will be used along with a benchmark application to develop a comparative evaluation of the alternatives that maybe used by wind energy/bulk transmission developers for performing engineering trade-off studies.

  4. Comprehensive characterization of printed circuit boards of various end-of-life electrical and electronic equipment for beneficiation investigation.

    Science.gov (United States)

    Anshu Priya; Hait, Subrata

    2018-05-01

    Comprehensive characterization of printed circuit board (PCB) of end-of-life electrical and electronic equipment (EEE) is obligatory for prospective profitable beneficiation. In this study, beneficiation oriented comprehensive characterization of two brands of PCBs each of 16 end-of-life EEE was conducted in terms of their physicochemical characteristics with special emphasis on the content of 16 general elements, 2 precious metals and 15 rare earth elements (REEs). General elements and their highest weight percent composition found in different PCBs of the EEEs were Cu (23% in laptop), Al (6% in computer), Pb (15% in DVD player) and Ba (7% in TV). The high abundant of precious metals such as Au (316 g/ton) and Ag (636 g/ton) in mobile phone and laptop, respectively coupled with rapid obsolescence age makes waste PCBs of information technology and telecommunication equipment the most potent resource reservoir. Additionally, most of the waste PCBs were observed to contain REEs in considerable quantity with Sc up to 31 g/ton and Ce up to 13 g/ton being the major constituents. Comprehensive characterization of waste PCBs therefore will systematically help towards better understanding of e-waste recycling processes for beneficiation purpose and sustainable resource circulation and conservation. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Measuring for enhancing high school students’ cooperative attitude and responsibilities in learning closed electrical circuits through STEM approach

    Science.gov (United States)

    Rusnayati, H.; Masripah, I.; Suwarma, I. R.

    2018-05-01

    This study conducted by the finding of the lack of students’ cooperative attitude that gained 35.29% and the students’ responsibility 29.41%. It also looks at the preliminary study that conducted by the observation group obtained the students’ cooperative attitude (34%) and student’s responsibility (30%). The purpose of this study to determine students’ cooperative attitude and responsibility at the time of learning a closed electrical circuit through STEM approach. This research method is the descriptive study with the pre-experimental design and the paradigm of one shot case study. The population of this study is the tenth-grade high school students with a sample size of 40 students that consist of 24 female and 16 male. The data collection techniques that utilized is the attitude rubric and the attitude measurement format. The result of this study showed that the percentage of students’ cooperative attitude in the first and second meeting is 83% and 81% with very high criteria. Meanwhile, the attitude of responsibility answerable for the first and second meeting was 81% and 79% with very high and high criteria. This indicates that the STEM approach can improve students’ cooperative attitude and responsibility.

  6. Description of Self-efficacy and Initial Cognitive Abilities on the Students’ Physics Learning of the Direct Current Electrical Circuits

    Science.gov (United States)

    Zaenudin; Maknun, J.; Muslim

    2017-03-01

    This study aims to determine description of self -efficacy and initial cognitive abilities on the students of MAN 1 Bandung (senior high school) in learning physics on the subject of electrical circuits Direct Current (DC) before they get academy ask assigned in the classroom. From the results of this research can be used as a reference to provide appropriate measures for the advancement of student learning. The theory used in this research is the theory of Bandura. The design in this study using case study and data collection is done by tests and questionnaires, sampling techniques used by random sampling, the study was conducted on 10th grade students of MAN 1 Bandung by the amount of students 35 participants. The results of data analysis showed that the percentage of students who have moderate self-efficacy amounted to 67.05 %, and cognitive ability 50 %, this shows that the process of learning that takes place in school before that junior high school is not much scientific implement processes that provide students the opportunity to discover new things, then learning approaches of right is Problem Based Learning (PBL).

  7. Global changes in total and wind electricity (1990–2014

    Directory of Open Access Journals (Sweden)

    María del P. Pablo-Romero

    2017-03-01

    Full Text Available Wind energy is one of the renewable energies which have less adverse environmental impact and is becoming economically affordable long before several other renewable energies. Over recent years, substantial additions have been noted in wind energy capacity, although many differences can be observed between countries. Using the latest available data, this paper provides a concise analysis of wind energy and electricity consumption trends for the period 1990–2014 in a dual perspective, by principal world regions and by per capita gross national income levels in 2014. Electricity consumption has been divided into three types of energy: non-renewable, renewable excluding wind and wind energy. Annual rates of change, energy intensity, energy in per capita terms and some ratios have been analyzed. Notable regional differences and trends are observed in the studied variables. The first 15 European Union countries, other developed countries (ODC and East Asian (EAS and South Asian countries (SAS are the regions which currently have the highest wind capacity.

  8. Global distribution of grid connected electrical energy storage systems

    Directory of Open Access Journals (Sweden)

    Katja Buss

    2016-06-01

    Full Text Available This article gives an overview of grid connected electrical energy storage systems worldwide, based on public available data. Technologies considered in this study are pumped hydroelectric energy storage (PHES, compressed air energy storage (CAES, sodium-sulfur batteries (NaS, lead-acid batteries, redox-flow batteries, nickel-cadmium batteries (NiCd and lithium-ion batteries. As the research indicates, the worldwide installed capacity of grid connected electrical energy storage systems is approximately 154 GW. This corresponds to a share of 5.5 % of the worldwide installed generation capacity. Furthermore, the article gives an overview of the historical development of installed and used storage systems worldwide. Subsequently, the focus is on each considered technology concerning the current storage size, number of plants and location. In summary it can be stated, PHES is the most commonly used technology worldwide, whereas electrochemical technologies are increasingly gaining in importance. Regarding the distribution of grid connected storage systems reveals the share of installed storage capacity is in Europe and Eastern Asia twice as high as in North America.

  9. Electrical circuit for checking the state of charge of a vehicle battery. Elektrische Schaltung zur Kontrolle des Ladezustandes einer Batterie in Kraftfahrzeugen

    Energy Technology Data Exchange (ETDEWEB)

    Gamulescu, A

    1981-05-27

    The invention concerns an electrical circuit for checking the state of charge of a vehicle battery. The circuit consists of a transistor, whose collector is connected via a series resistance and a Zener diode to the positive pole of the battery. The breakdown voltage of the Zener diode is about 12 volts. The emitter of the transistor is connected via an LED to earth. A second LED is connected in parallel with the collector-emitter circuit of the transistor, which works via a voltage divider. This voltage divider reduces the voltage at the LED with the transistor which is conducting to about 0.7 volts. A second Zener diode connected via a series resistance to the positive pole is also provided. Its breakdown voltage is 15 volts.

  10. Effect of the depth base along the vertical on the electrical parameters of a vertical parallel silicon solar cell in open and short circuit

    Directory of Open Access Journals (Sweden)

    Gokhan Sahin

    2018-03-01

    Full Text Available This article presented a modeling study of effect of the depth base initiating on vertical parallel silicon solar cell’s photovoltaic conversion efficiency. After the resolution of the continuity equation of excess minority carriers, we calculated the electrical parameters such as the photocurrent density, the photovoltage, series resistance and shunt resistances, diffusion capacitance, electric power, fill factor and the photovoltaic conversion efficiency. We determined the maximum electric power, the operating point of the solar cell and photovoltaic conversion efficiency according to the depth z in the base. We showed that the photocurrent density decreases with the depth z. The photovoltage decreased when the depth base increases. Series and shunt resistances were deduced from electrical model and were influenced and the applied the depth base. The capacity decreased with the depth z of the base. We had studied the influence of the variation of the depth z on the electrical parameters in the base. Keywords: Depth base, Conversion efficiency, Electrical parameters, Open circuit, Short circuit

  11. Electric theory

    International Nuclear Information System (INIS)

    Gong, Ha Seong

    2006-02-01

    This book explains electric theory which is divided into four chapters. The first chapter includes electricity and material, electric field, capacitance, magnetic field and electromagnetic force, inductance. The second chapter mentions electronic circuit analysis, electric resistance,heating and power, chemical activity on current and battery with electrolysis. The third chapter deals with an alternating current circuit about the basics of an AC circuit, operating of resistance, inductance and capacitance, series circuit and parallel circuit of PLC, an alternating current circuit, Three-phase Alternating current, two terminal pair network and voltage and current of non-linearity circuit. The last explains transient phenomena of RC series circuit, RL series circuit, transient phenomena of an alternating current circuit and transient phenomena of RLC series circuit.

  12. "ONE PERCENT INSPIRATION AND 99 PERCENT TRACING PAPER”: THE PAN-ELECTRIC SCANDAL AND THE MAKING OF A CIRCUIT COURT JUDGE, APRIL-NOVEMBER 1886

    OpenAIRE

    Harvey Gresham Hudspeth

    2005-01-01

    The Pan-Electric scandal of 1886 grew out of a plot by prominent Southern Democrats to seize control of the fledgling telephone industry by filing suit in federal court to invalidate patents held by Alexander Graham Bell and Bell Telephone. The suit led to President Grover Cleveland's appointment of Tennessee senator Howell Edmunds Jackson to the Sixth Circuit federal court and a ruling by Jackson that led to the final court victory for Bell.

  13. "ONE PERCENT INSPIRATION AND 99 PERCENT TRACING PAPER”: THE PAN-ELECTRIC SCANDAL AND THE MAKING OF A CIRCUIT COURT JUDGE, APRIL-NOVEMBER 1886

    Directory of Open Access Journals (Sweden)

    Harvey Gresham Hudspeth

    2005-01-01

    Full Text Available The Pan-Electric scandal of 1886 grew out of a plot by prominent Southern Democrats to seize control of the fledgling telephone industry by filing suit in federal court to invalidate patents held by Alexander Graham Bell and Bell Telephone. The suit led to President Grover Cleveland's appointment of Tennessee senator Howell Edmunds Jackson to the Sixth Circuit federal court and a ruling by Jackson that led to the final court victory for Bell.

  14. Assessing the global sustainability of different electricity generation systems

    International Nuclear Information System (INIS)

    Cartelle Barros, Juan José; Lara Coira, Manuel; Cruz López, María Pilar de la; Caño Gochi, Alfredo del

    2015-01-01

    A model is presented for assessing the global sustainability of power plants. It uses requirement trees, value functions and the analytic hierarchy process. The model consists of 27 parameters and makes it possible to obtain a sustainability index for each conventional or renewable energy plant, throughout its life-cycle. Here the aim is to make society aware of the sustainability level for each type of power system. As a result, decision making can be done with greater objectivity in both the public and private sectors. The model can be useful for engineers, researchers and, in general, decision makers in the energy policy field. With the exception of biomass fuels, the results obtained reinforce the idea that renewable energies make a greater contribution to sustainable development than their conventional counterparts. Renewable energies have a sustainability index that varies between 0.39 and 0.80; 0 and 1 being the lowest and highest contribution to sustainability, respectively. On the other hand, conventional power plants obtained results that fall between 0.29 and 0.57. High temperature solar-thermal plants, wind farms, photovoltaic solar plants and mini-hydroelectric power plants occupy the first four places, in this order. - Highlights: • A model for assessing the integral sustainability of power plants is proposed. • Different energy alternatives are ordered according to sustainability criteria. • Except for biomass, renewable energies contribute more to sustainable development. • The model aids the decision making process in the energy policy field

  15. Lithium Ion Batteries—Development of Advanced Electrical Equivalent Circuit Models for Nickel Manganese Cobalt Lithium-Ion

    Directory of Open Access Journals (Sweden)

    Alexandros Nikolian

    2016-05-01

    Full Text Available In this paper, advanced equivalent circuit models (ECMs were developed to model large format and high energy nickel manganese cobalt (NMC lithium-ion 20 Ah battery cells. Different temperatures conditions, cell characterization test (Normal and Advanced Tests, ECM topologies (1st and 2nd Order Thévenin model, state of charge (SoC estimation techniques (Coulomb counting and extended Kalman filtering and validation profiles (dynamic discharge pulse test (DDPT and world harmonized light vehicle profiles have been incorporated in the analysis. A concise state-of-the-art of different lithium-ion battery models existing in the academia and industry is presented providing information about model classification and information about electrical models. Moreover, an overview of the different steps and information needed to be able to create an ECM model is provided. A comparison between begin of life (BoL and aged (95%, 90% state of health ECM parameters (internal resistance (Ro, polarization resistance (Rp, activation resistance (Rp2 and time constants (τ is presented. By comparing the BoL to the aged parameters an overview of the behavior of the parameters is introduced and provides the appropriate platform for future research in electrical modeling of battery cells covering the ageing aspect. Based on the BoL parameters 1st and 2nd order models were developed for a range of temperatures (15 °C, 25 °C, 35 °C, 45 °C. The highest impact to the accuracy of the model (validation results is the temperature condition that the model was developed. The 1st and 2nd order Thévenin models and the change from normal to advanced characterization datasets, while they affect the accuracy of the model they mostly help in dealing with high and low SoC linearity problems. The 2nd order Thévenin model with advanced characterization parameters and extended Kalman filtering SoC estimation technique is the most efficient and dynamically correct ECM model developed.

  16. Potential for reducing global carbon emissions from electricity production-A benchmarking analysis

    International Nuclear Information System (INIS)

    Ang, B.W.; Zhou, P.; Tay, L.P.

    2011-01-01

    We present five performance indicators for electricity generation for 129 countries using the 2005 data. These indicators, measured at the national level, are the aggregate CO 2 intensity of electricity production, the efficiencies of coal, oil and gas generation and the share of electricity produced from non-fossil fuels. We conduct a study on the potential for reducing global energy-related CO 2 emissions from electricity production through simple benchmarking. This is performed based on the last four performance indicators and the construction of a cumulative curve for each of these indicators. It is found that global CO 2 emissions from electricity production would be reduced by 19% if all these indicators are benchmarked at the 50th percentile. Not surprisingly, the emission reduction potential measured in absolute terms is the highest for large countries such as China, India, Russia and the United States. When the potential is expressed as a percentage of a country's own emissions, few of these countries appear in the top-five list. - Research highlights: → We study variations in emissions per kWh of electricity generated among countries. → We analyze emissions from electricity production through benchmarking. → Estimates of reduction in emissions are made based on different assumptions.

  17. Modeling the UT effect in global distribution of ionospheric electric fields

    DEFF Research Database (Denmark)

    Lukianova, R.; Christiansen, Freddy

    2008-01-01

    A new approach for modeling the global distribution of ionospheric electric potentials utilizing high-precision maps of field-aligned currents (FACs) derived from measurements by the Orsted and Magsat satellites as input to a comprehensive numerical scheme is presented. We simulate the universal ...

  18. Examining global electricity supply vulnerability to climate change using a high-fidelity hydropower dam model.

    Science.gov (United States)

    Turner, Sean W D; Ng, Jia Yi; Galelli, Stefano

    2017-07-15

    An important and plausible impact of a changing global climate is altered power generation from hydroelectric dams. Here we project 21st century global hydropower production by forcing a coupled, global hydrological and dam model with three General Circulation Model (GCM) projections run under two emissions scenarios. Dams are simulated using a detailed model that accounts for plant specifications, storage dynamics, reservoir bathymetry and realistic, optimized operations. We show that the inclusion of these features can have a non-trivial effect on the simulated response of hydropower production to changes in climate. Simulation results highlight substantial uncertainty in the direction of change in globally aggregated hydropower production (~-5 to +5% change in mean global production by the 2080s under a high emissions scenario, depending on GCM). Several clearly impacted hotspots are identified, the most prominent of which encompasses the Mediterranean countries in southern Europe, northern Africa and the Middle East. In this region, hydropower production is projected to be reduced by approximately 40% on average by the end of the century under a high emissions scenario. After accounting for each country's dependence on hydropower for meeting its current electricity demands, the Balkans countries emerge as the most vulnerable (~5-20% loss in total national electricity generation depending on country). On the flipside, a handful of countries in Scandinavia and central Asia are projected to reap a significant increase in total electrical production (~5-15%) without investing in new power generation facilities. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Resistor Combinations for Parallel Circuits.

    Science.gov (United States)

    McTernan, James P.

    1978-01-01

    To help simplify both teaching and learning of parallel circuits, a high school electricity/electronics teacher presents and illustrates the use of tables of values for parallel resistive circuits in which total resistances are whole numbers. (MF)

  20. Electric engineering introduction

    International Nuclear Information System (INIS)

    An, Byeong Won; Eom, Sang Ho

    1999-03-01

    It is divided into nine chapters, which includes electricity theory such as structure of material and current, nature of electricity, static, magnetic force and magnetic attraction, attraction of current and a storage battery, electric circuit on a direct current circuit, single phase circuit and 3-phase current circuit electricity machine like DC generator, DC motor, alternator, electric transformer, single-phase induction motor, 3-phase induction motor, synchronous motor, synchro electric machine, semiconductor such as diode, transistor, FET, UJT, silicon symmetrical switch, electronic circuit like smoothing circuit and Bistable MV. circuit, automatic control, measurement of electricity, electric application and safety.

  1. A New Approach for Modeling Darrieus-Type Vertical Axis Wind Turbine Rotors Using Electrical Equivalent Circuit Analogy: Basis of Theoretical Formulations and Model Development

    Directory of Open Access Journals (Sweden)

    Pierre Tchakoua

    2015-09-01

    Full Text Available Models are crucial in the engineering design process because they can be used for both the optimization of design parameters and the prediction of performance. Thus, models can significantly reduce design, development and optimization costs. This paper proposes a novel equivalent electrical model for Darrieus-type vertical axis wind turbines (DTVAWTs. The proposed model was built from the mechanical description given by the Paraschivoiu double-multiple streamtube model and is based on the analogy between mechanical and electrical circuits. This work addresses the physical concepts and theoretical formulations underpinning the development of the model. After highlighting the working principle of the DTVAWT, the step-by-step development of the model is presented. For assessment purposes, simulations of aerodynamic characteristics and those of corresponding electrical components are performed and compared.

  2. 77 FR 13367 - General Electric-Hitachi Global Laser Enrichment, LLC, Proposed Laser-Based Uranium Enrichment...

    Science.gov (United States)

    2012-03-06

    ... NUCLEAR REGULATORY COMMISSION [NRC-2009-0157] General Electric-Hitachi Global Laser Enrichment, LLC, Proposed Laser-Based Uranium Enrichment Facility, Wilmington, NC AGENCY: Nuclear Regulatory... Impact Statement (EIS) for the proposed General Electric- Hitachi Global Laser Enrichment, LLC (GLE...

  3. Dynamics of global supply chain and electric power networks: Models, pricing analysis, and computations

    Science.gov (United States)

    Matsypura, Dmytro

    In this dissertation, I develop a new theoretical framework for the modeling, pricing analysis, and computation of solutions to electric power supply chains with power generators, suppliers, transmission service providers, and the inclusion of consumer demands. In particular, I advocate the application of finite-dimensional variational inequality theory, projected dynamical systems theory, game theory, network theory, and other tools that have been recently proposed for the modeling and analysis of supply chain networks (cf. Nagurney (2006)) to electric power markets. This dissertation contributes to the extant literature on the modeling, analysis, and solution of supply chain networks, including global supply chains, in general, and electric power supply chains, in particular, in the following ways. It develops a theoretical framework for modeling, pricing analysis, and computation of electric power flows/transactions in electric power systems using the rationale for supply chain analysis. The models developed include both static and dynamic ones. The dissertation also adds a new dimension to the methodology of the theory of projected dynamical systems by proving that, irrespective of the speeds of adjustment, the equilibrium of the system remains the same. Finally, I include alternative fuel suppliers, along with their behavior into the supply chain modeling and analysis framework. This dissertation has strong practical implications. In an era in which technology and globalization, coupled with increasing risk and uncertainty, complicate electricity demand and supply within and between nations, the successful management of electric power systems and pricing become increasingly pressing topics with relevance not only for economic prosperity but also national security. This dissertation addresses such related topics by providing models, pricing tools, and algorithms for decentralized electric power supply chains. This dissertation is based heavily on the following

  4. Hybrid finite difference/finite element solution method development for non-linear superconducting magnet and electrical circuit breakdown transient analysis

    International Nuclear Information System (INIS)

    Kraus, H.G.; Jones, J.L.

    1986-01-01

    The problem of non-linear superconducting magnet and electrical protection circuit system transients is formulated. To enable studying the effects of coil normalization transients, coil distortion (due to imbalanced magnetic forces), internal coil arcs and shorts, and other normal and off-normal circuit element responses, the following capabilities are included: temporal, voltage and current-dependent voltage sources, current sources, resistors, capacitors and inductors. The concept of self-mutual inductance, and the form of the associated inductance matrix, is discussed for internally shorted coils. This is a Kirchhoff's voltage loop law and Kirchhoff's current node law formulation. The non-linear integrodifferential equation set is solved via a unique hybrid finite difference/integral finite element technique. (author)

  5. Inverted Fuel Cell: Room-Temperature Hydrogen Separation from an Exhaust Gas by Using a Commercial Short-Circuited PEM Fuel Cell without Applying any Electrical Voltage.

    Science.gov (United States)

    Friebe, Sebastian; Geppert, Benjamin; Caro, Jürgen

    2015-06-26

    A short-circuited PEM fuel cell with a Nafion membrane has been evaluated in the room-temperature separation of hydrogen from exhaust gas streams. The separated hydrogen can be recovered or consumed in an in situ olefin hydrogenation when the fuel cell is operated as catalytic membrane reactor. Without applying an outer electrical voltage, there is a continuous hydrogen flux from the higher to the lower hydrogen partial pressure side through the Nafion membrane. On the feed side of the Nafion membrane, hydrogen is catalytically split into protons and electrons by the Pt/C electrocatalyst. The protons diffuse through the Nafion membrane, the electrons follow the short-circuit between the two brass current collectors. On the cathode side, protons and electrons recombine, and hydrogen is released. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Analog circuits cookbook

    CERN Document Server

    Hickman, Ian

    2013-01-01

    Analog Circuits Cookbook presents articles about advanced circuit techniques, components and concepts, useful IC for analog signal processing in the audio range, direct digital synthesis, and ingenious video op-amp. The book also includes articles about amplitude measurements on RF signals, linear optical imager, power supplies and devices, and RF circuits and techniques. Professionals and students of electrical engineering will find the book informative and useful.

  7. Potential for reducing global carbon emissions from electricity production-A bench marking analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ang, B.W.; Zhou, P.; Tay, L.P. [National University of Singapore (Singapore). Department of Industrial and Systems Engineering

    2011-05-15

    We present five performance indicators for electricity generation for 129 countries using the 2005 data. These indicators, measured at the national level, are the aggregate CO{sub 2} intensity of electricity production, the efficiencies of coal, oil and gas generation and the share of electricity produced from non-fossil fuels. We conduct a study on the potential for reducing global energy-related CO{sub 2} emissions from electricity production through simple bench marking. This is performed based on the last four performance indicators and the construction of a cumulative curve for each of these indicators. It is found that global CO{sub 2} emissions from electricity production would be reduced by 19% if all these indicators are benchmarked at the 50th percentile. Not surprisingly, the emission reduction potential measured in absolute terms is the highest for large countries such as China, India, Russia and the United States. When the potential is expressed as a percentage of a country's own emissions, few of these countries appear in the top-five list. 14 refs., 8 figs., 4 tabs.

  8. Perspectives of the electric power industry amid the transforming global power generation markets

    Science.gov (United States)

    Makarov, A. A.; Mitrova, T. A.; Veselov, F. V.; Galkina, A. A.; Kulagin, V. A.

    2017-10-01

    A scenario-based prognosis of the evolution of global power generation markets until 2040, which was developed using the Scaner model-and-information complex, was given. The perspective development of fuel markets, vital for the power generation industry, was considered, and an attempt to predict the demand, production, and prices of oil, gas, coal, and noncarbon resources across various regions of the world was made. The anticipated decline in the growth of the global demand for fossil fuels and their sufficiency with relatively low extraction expenses will maintain the fuel prices (the data hereinafter are given as per 2014 prices) lower than their peak values in 2012. The outrunning growth of demand for electric power is shown in comparison with other power resources by regions and large countries in the world. The conditions of interfuel competition in the electric power industry considering the changes in anticipated fuel prices and cost indicators for various power generation technologies were studied. For this purpose, the ratios of discounted costs of electric power production by new gas and coal TPPs and wind and solar power plants were estimated. It was proven that accounting the system effects (operation modes, necessary duplicating and reserving the power of electric power plants using renewable energy sources) notably reduces the competitiveness of the renewable power industry and is not always compensated by the expected lowering of its capital intensity and growth of fuel for TPPs. However, even with a moderate (in relation to other prognoses) growth of the role of power plants using renewable energy sources, they will triple electric power production. In this context, thermal power plants will preserve their leadership covering up to 60% of the global electric power production, approximately half using gas.

  9. The electric sector and its insert in a global scenery; O setor eletrico e sua insercao num cenario globalizado

    Energy Technology Data Exchange (ETDEWEB)

    Serrano, Ricardo Oliveira Lopes

    1999-11-01

    The document discusses the following issues of the Brazilian electric power sector: historical aspects; the creation of the ELETROBRAS and the sectorial debts process; financial and productive globalization; electric industry and the new environment and the new businesses. The author concludes the work detaching the new business appearance in the Brazilian electric power sector.

  10. Electric power and the global economy: Advances in database construction and sector representation

    Science.gov (United States)

    Peters, Jeffrey C.

    The electricity sector plays a crucial role in the global economy. The sector is a major consumer of fossil fuel resources, producer of greenhouse gas emissions, and an important indicator and correlate of economic development. As such, the sector is a primary target for policy-makers seeking to address these issues. The sector is also experiencing rapid technological change in generation (e.g. renewables), primary inputs (e.g. horizontal drilling and hydraulic fracturing), and end-use efficiency. This dissertation seeks to further our understanding of the role of the electricity sector as part of the dynamic global energy-economy, which requires significant research advances in both database construction and modeling techniques. Chapter 2 identifies useful engineering-level data and presents a novel matrix balancing method for integrating these data in global economic databases. Chapter 3 demonstrates the relationship between matrix balancing method and modeling results, and Chapter 4 presents the full construction methodology for GTAP-Power, the foremost, publicly-available global computable general equilibrium database. Chapter 5 presents an electricity-detailed computational equilibrium model that explicitly and endogenously captures capacity utilization, capacity expansion, and their interdependency - important aspects of technological substitution in the electricity sector. The individual, but interrelated, research contributions to database construction and electricity modeling in computational equilibrium are placed in the context of analyzing the US EPA Clean Power Plan (CPP) CO 2 target of 32 percent reduction of CO2 emissions in the US electricity sector from a 2005 baseline by 2030. Assuming current fuel prices, the model predicts an almost 28 percent CO2 reduction without further policy intervention. Next, a carbon tax and investment subsidies for renewable technologies to meet the CPP full targets are imposed and compared (Chapter 6). The carbon tax

  11. Printed circuit for ATLAS

    CERN Multimedia

    Laurent Guiraud

    1999-01-01

    A printed circuit board made by scientists in the ATLAS collaboration for the transition radiaton tracker (TRT). This will read data produced when a high energy particle crosses the boundary between two materials with different electrical properties.

  12. Forecast and analysis of the ratio of electric energy to terminal energy consumption for global energy internet

    Science.gov (United States)

    Wang, Wei; Zhong, Ming; Cheng, Ling; Jin, Lu; Shen, Si

    2018-02-01

    In the background of building global energy internet, it has both theoretical and realistic significance for forecasting and analysing the ratio of electric energy to terminal energy consumption. This paper firstly analysed the influencing factors of the ratio of electric energy to terminal energy and then used combination method to forecast and analyse the global proportion of electric energy. And then, construct the cointegration model for the proportion of electric energy by using influence factor such as electricity price index, GDP, economic structure, energy use efficiency and total population level. At last, this paper got prediction map of the proportion of electric energy by using the combination-forecasting model based on multiple linear regression method, trend analysis method, and variance-covariance method. This map describes the development trend of the proportion of electric energy in 2017-2050 and the proportion of electric energy in 2050 was analysed in detail using scenario analysis.

  13. Sustainability of sources of electric generation: indicators and global qualification using fuzzy logic

    International Nuclear Information System (INIS)

    Martin del Campo M, C.; Francois L, J.L.

    2005-01-01

    A methodology developed to evaluate the sustainability of sources of electric generation but used in Mexico and in the World is presented. For it was applied one matrix of sustainability indicators that considers the principles and criteria of general sustainability as 'not exhaustion of natural resources', 'non production of non degradable waste', and 'not high sensibility to social and environmental factors'. The approaches to evaluate in a wide way these principles are numerous and to each approach associates an indicator, call sustainability indicator. The contribution of this work consists on the development of a methodology to qualify globally the sustainability of each option of electric generation, combining all the sustainability indicators. The methodology applies a system of diffuse control to build the function of global qualification of sustainability dependent of all the indicators. (Author)

  14. The role of electricity storage and hydrogen technologies in enabling global low-carbon energy transitions

    OpenAIRE

    McPherson, M.; Johnson, N.; Strubegger, M.

    2018-01-01

    Previous studies have noted the importance of electricity storage and hydrogen technologies for enabling large-scale variable renewable energy (VRE) deployment in long-term climate change mitigation scenarios. However, global studies, which typically use integrated assessment models, assume a fixed cost trajectory for storage and hydrogen technologies; thereby ignoring the sensitivity of VRE deployment and/or mitigation costs to uncertainties in future storage and hydrogen technology costs. Y...

  15. Electric power globalization and reforming; Globalizacao e reforma do setor eletrico

    Energy Technology Data Exchange (ETDEWEB)

    Soares Neto, Jose Lino [PETROBRAS Distribuidora, Rio de Janeiro, RJ (Brazil)

    1999-07-01

    The central issue of debate was the need to align the energy sector's options and organization with changing global patterns of economic and social development, characterized by the increasing role played by the private sector, greater integration in the world economy, and new economic and social priorities such as efficiency, decentralization, deregulation, and a closer attention to environmental issues. The aim of the work was to define the economic and political forces of the electric power sector regulation restructuring.

  16. The supply and demand on fuel energy and electricity. Global environmental impact

    International Nuclear Information System (INIS)

    Leydon, K.; and others.

    1992-01-01

    The material is one of four review articles presented at Senior Expert Symposium on Electricity and Environment, Helsinki, Finland, 13-17 May 1991. The present impact and future prognosis of influence of power industry on global environment have been performed. The possibility of improvement by application of environment friendly technologies and energy sources have been discussed in respect to different countries and world regions. 14 refs, 12 figs, 9 tabs

  17. Electric circuit coupling of a slotted semi-analytical model for induction motors based on harmonic modeling

    NARCIS (Netherlands)

    Sprangers, R.L.J.; Paulides, J.J.H.; Gysen, B.L.J.; Waarma, J.; Lomonova, E.A.

    2014-01-01

    The use of empirically determined coefficients to include the effects of leakage and fringing flux is a large drawback of traditional induction motor (IM) models, such as lumped parameter, magnetic equivalent circuit and anisotropic layer models. As an alternative, Finite Element Analysis (FEA) is

  18. A Study of University Students' Understanding of Simple Electric Circuits. Part 2: Batteries, Ohm's Law, Power Dissipated, Resistors in Parallel.

    Science.gov (United States)

    Picciarelli, V.; And Others

    1991-01-01

    Results of a systematic investigation into university students' (n=236) misunderstandings of d.c. simple circuit operations are reported. These results provide evidence of various misconceptions present before and after teaching the following topics: a battery as a source of constant current; the functional relation expressed by Ohm's law; power…

  19. Global environmental issues and electric power in the twenty-first century

    International Nuclear Information System (INIS)

    Hidy, G.M.; Spencer, D.F.

    1993-01-01

    Development of the electric utility industry in the 21st Century will be central to the well-being of mankind. Electricity worldwide is still likely to be produced mainly from fossil fuel combustion for the foreseeable future. On a global scale, this energy sector will contribute to growing carbon dioxide (CO 2 ) emissions through most of the next century. A potential for global climate alteration has been identified with accumulation of CO 2 and other greenhouse gases (GHGs) in the Earth's atmosphere. If climate changes, adverse environmental effects are possible, acting on human systems, as well as on managed and natural ecosystems. Projected rates of increase in atmospheric CO 2 levels for the next century have motivated decision makers to consider early strategies for beginning to aggressively manage GHG emissions. The objective of this paper is to review the global issues associated with expected increases in gaseous emissions, particularly carbon dioxide from increased energy use, indicating the nature and significance of the issue. The authors emphasize a methodology integrating information on environmental issues with social and economic factors to develop informed international policies. The paper summarizes the technological choices available worldwide that could minimize the environmental impact of increasing energy use, particularly with respect to enhanced electricity production

  20. Flip-flop logic circuit based on fully solution-processed organic thin film transistor devices with reduced variations in electrical performance

    Science.gov (United States)

    Takeda, Yasunori; Yoshimura, Yudai; Adib, Faiz Adi Ezarudin Bin; Kumaki, Daisuke; Fukuda, Kenjiro; Tokito, Shizuo

    2015-04-01

    Organic reset-set (RS) flip-flop logic circuits based on pseudo-CMOS inverters have been fabricated using full solution processing at a relatively low process temperatures of 150 °C or less. The work function for printed silver electrodes was increased from 4.7 to 5.4 eV through surface modification with a self-assembled monolayer (SAM) material. A bottom-gate, bottom-contact organic thin-film transistor (OTFT) device using a solution-processable small-molecular semiconductor material exhibited field-effect mobility of 0.40 cm2 V-1 s-1 in the saturation region and a threshold voltage (VTH) of -2.4 V in ambient air operation conditions. In order to reduce the variations in mobility and VTH, we designed a circuit with six transistors arranged in parallel, in order to average out their electrical characteristics. As a result, we have succeeded in reducing these variations without changing the absolute values of the mobility and VTH. The fabricated RS flip-flop circuits were functioned well and exhibited short delay times of 3.5 ms at a supply voltage of 20 V.

  1. Electric Circuit Model for the Aerodynamic Performance Analysis of a Three-Blade Darrieus-Type Vertical Axis Wind Turbine: The Tchakoua Model

    Directory of Open Access Journals (Sweden)

    Pierre Tchakoua

    2016-10-01

    Full Text Available The complex and unsteady aerodynamics of vertical axis wind turbines (VAWTs pose significant challenges for simulation tools. Recently, significant research efforts have focused on the development of new methods for analysing and optimising the aerodynamic performance of VAWTs. This paper presents an electric circuit model for Darrieus-type vertical axis wind turbine (DT-VAWT rotors. The novel Tchakoua model is based on the mechanical description given by the Paraschivoiu double-multiple streamtube model using a mechanical‑electrical analogy. Model simulations were conducted using MATLAB for a three-bladed rotor architecture, characterized by a NACA0012 profile, an average Reynolds number of 40,000 for the blade and a tip speed ratio of 5. The results obtained show strong agreement with findings from both aerodynamic and computational fluid dynamics (CFD models in the literature.

  2. MOS integrated circuit design

    CERN Document Server

    Wolfendale, E

    2013-01-01

    MOS Integral Circuit Design aims to help in the design of integrated circuits, especially large-scale ones, using MOS Technology through teaching of techniques, practical applications, and examples. The book covers topics such as design equation and process parameters; MOS static and dynamic circuits; logic design techniques, system partitioning, and layout techniques. Also featured are computer aids such as logic simulation and mask layout, as well as examples on simple MOS design. The text is recommended for electrical engineers who would like to know how to use MOS for integral circuit desi

  3. Linking neuroscientific research on decision making to the educational context of novice students assigned to a multiple-choice scientific task involving common misconceptions about electrical circuits

    Directory of Open Access Journals (Sweden)

    Patrice ePotvin

    2014-01-01

    Full Text Available Functional magnetic resonance imaging was used to identify the brain-based mechanisms of uncertainty and certainty associated with answers to multiple-choice questions involving common misconceptions about electric circuits. Twenty-two (22 scientifically novice participants (humanities and arts college students were asked, in an fMRI study, whether or not they thought the light bulbs in images presenting electric circuits were lighted up correctly, and if they were certain or uncertain of their answers. When participants reported that they were unsure of their responses, analyses revealed significant activations in brain areas typically involved in uncertainty (anterior cingulate cortex, anterior insula cortex, and superior/dorsomedial frontal cortex and in the left middle/superior temporal lobe. Certainty was associated with large bilateral activations in the occipital and parietal regions usually involved in visuospatial processing. Correct-and-certain answers were associated with activations that suggest a stronger mobilization of visual attention resources when compared to incorrect-and-certain answers. These findings provide insights into brain-based mechanisms of uncertainty that are activated when common misconceptions, identified as such by science education research literature, interfere in decision making in a school-like task. We also discuss the implications of these results from an educational perspective.

  4. Online model-based estimation of state-of-charge and open-circuit voltage of lithium-ion batteries in electric vehicles

    International Nuclear Information System (INIS)

    He, Hongwen; Zhang, Xiaowei; Xiong, Rui; Xu, Yongli; Guo, Hongqiang

    2012-01-01

    This paper presents a method to estimate the state-of-charge (SOC) of a lithium-ion battery, based on an online identification of its open-circuit voltage (OCV), according to the battery’s intrinsic relationship between the SOC and the OCV for application in electric vehicles. Firstly an equivalent circuit model with n RC networks is employed modeling the polarization characteristic and the dynamic behavior of the lithium-ion battery, the corresponding equations are built to describe its electric behavior and a recursive function is deduced for the online identification of the OCV, which is implemented by a recursive least squares (RLS) algorithm with an optimal forgetting factor. The models with different RC networks are evaluated based on the terminal voltage comparisons between the model-based simulation and the experiment. Then the OCV-SOC lookup table is built based on the experimental data performed by a linear interpolation of the battery voltages at the same SOC during two consecutive discharge and charge cycles. Finally a verifying experiment is carried out based on nine Urban Dynamometer Driving Schedules. It indicates that the proposed method can ensure an acceptable accuracy of SOC estimation for online application with a maximum error being less than 5.0%. -- Highlights: ► An equivalent circuit model with n RC networks is built for lithium-ion batteries. ► A recursive function is deduced for the online estimation of the model parameters like OCV and R O . ► The relationship between SOC and OCV is built with a linear interpolation method by experiments. ► The experiments show the online model-based SOC estimation is reasonable with enough accuracy.

  5. [Shunt and short circuit].

    Science.gov (United States)

    Rangel-Abundis, Alberto

    2006-01-01

    Shunt and short circuit are antonyms. In French, the term shunt has been adopted to denote the alternative pathway of blood flow. However, in French, as well as in Spanish, the word short circuit (court-circuit and cortocircuito) is synonymous with shunt, giving rise to a linguistic and scientific inconsistency. Scientific because shunt and short circuit made reference to a phenomenon that occurs in the field of the physics. Because shunt and short circuit are antonyms, it is necessary to clarify that shunt is an alternative pathway of flow from a net of high resistance to a net of low resistance, maintaining the stream. Short circuit is the interruption of the flow, because a high resistance impeaches the flood. This concept is applied to electrical and cardiovascular physiology, as well as to the metabolic pathways.

  6. Oscillator circuits

    CERN Document Server

    Graf, Rudolf F

    1996-01-01

    This series of circuits provides designers with a quick source for oscillator circuits. Why waste time paging through huge encyclopedias when you can choose the topic you need and select any of the specialized circuits sorted by application?This book in the series has 250-300 practical, ready-to-use circuit designs, with schematics and brief explanations of circuit operation. The original source for each circuit is listed in an appendix, making it easy to obtain additional information.Ready-to-use circuits.Grouped by application for easy look-up.Circuit source listing

  7. Measuring circuits

    CERN Document Server

    Graf, Rudolf F

    1996-01-01

    This series of circuits provides designers with a quick source for measuring circuits. Why waste time paging through huge encyclopedias when you can choose the topic you need and select any of the specialized circuits sorted by application?This book in the series has 250-300 practical, ready-to-use circuit designs, with schematics and brief explanations of circuit operation. The original source for each circuit is listed in an appendix, making it easy to obtain additional information.Ready-to-use circuits.Grouped by application for easy look-up.Circuit source listings

  8. EV City Casebook: A Look At The Global Electric Vehicle Movement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    Electric vehicles (EVs) hold the potential of transforming the way the world moves. EVs can increase energy security by diversifying the fuel mix and decreasing dependence on petroleum, while also reducing emissions of greenhouse gases and other pollutants. Just as important, EVs can unlock innovation and create new advanced industries that spur job growth and enhance economic prosperity. However, the mass deployment of EVs will require transportation systems capable of integrating and fostering this new technology. To accelerate this transition, cities and metropolitan regions around the world are creating EV-friendly ecosystems and building the foundation for widespread adoption. In recognition of the importance of urban areas in the introduction and scale-up of electric vehicles, the EV City Casebook presents informative case studies on city and regional EV deployment efforts around the world. These case studies are illustrative examples of how pioneering cities are preparing the ground for mass market EV deployment. They offer both qualitative and quantitative information on cities' EV goals, progress, policies, incentives, and lessons learned to date. The purpose of the EV City Casebook is to share experiences on EV demonstration and deployment, identify challenges and opportunities, and highlight best practices for creating thriving EV ecosystems. These studies seek to enhance understanding of the most effective policy measures to foster the uptake of electric vehicles in urban areas. The cities represented here are actively engaging in a variety of initiatives that share the goal of accelerating EV adoption. This publication is the result of an effort to coordinate those initiatives and provide a global perspective on the electric vehicle movement. This international knowledge-sharing network consists of the Electric Vehicles Initiative (EVI), a multi-government initiative of the Clean Energy Ministerial; Project Get Ready, a Rocky Mountain Institute (RMI

  9. EV City Casebook: A Look At The Global Electric Vehicle Movement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    Electric vehicles (EVs) hold the potential of transforming the way the world moves. EVs can increase energy security by diversifying the fuel mix and decreasing dependence on petroleum, while also reducing emissions of greenhouse gases and other pollutants. Just as important, EVs can unlock innovation and create new advanced industries that spur job growth and enhance economic prosperity. However, the mass deployment of EVs will require transportation systems capable of integrating and fostering this new technology. To accelerate this transition, cities and metropolitan regions around the world are creating EV-friendly ecosystems and building the foundation for widespread adoption. In recognition of the importance of urban areas in the introduction and scale-up of electric vehicles, the EV City Casebook presents informative case studies on city and regional EV deployment efforts around the world. These case studies are illustrative examples of how pioneering cities are preparing the ground for mass market EV deployment. They offer both qualitative and quantitative information on cities' EV goals, progress, policies, incentives, and lessons learned to date. The purpose of the EV City Casebook is to share experiences on EV demonstration and deployment, identify challenges and opportunities, and highlight best practices for creating thriving EV ecosystems. These studies seek to enhance understanding of the most effective policy measures to foster the uptake of electric vehicles in urban areas. The cities represented here are actively engaging in a variety of initiatives that share the goal of accelerating EV adoption. This publication is the result of an effort to coordinate those initiatives and provide a global perspective on the electric vehicle movement. This international knowledge-sharing network consists of the Electric Vehicles Initiative (EVI), a multi-government initiative of the Clean Energy Ministerial; Project Get Ready, a Rocky Mountain Institute

  10. "Printed-circuit" rectenna

    Science.gov (United States)

    Dickinson, R. M.

    1977-01-01

    Rectifying antenna is less bulky structure for absorbing transmitted microwave power and converting it into electrical current. Printed-circuit approach, using microstrip technology and circularly polarized antenna, makes polarization orientation unimportant and allows much smaller arrays for given performance. Innovation is particularly useful with proposed electric vehicles powered by beam microwaves.

  11. Source-circuit design overview

    Science.gov (United States)

    Ross, R. G., Jr.

    1983-01-01

    The source circuit is the fundamental electrical building block of a large central-station array; it consists of a series-parallel network of solar cells that develops full system voltage. The array field is generally made up of a large number of parallel source circuits. Source-circuit electrical configuration is driven by a number of design considerations, which must be considered simultaneously. Array fault tolerance and hot spot heating endurance are examined in detail.

  12. GOING GLOBAL — ACTING LOCAL: SIEMENS IN THE CHINESE ELECTRICAL MARKET, 1904-1937

    Directory of Open Access Journals (Sweden)

    Mathias Mutz

    2011-01-01

    Full Text Available The German electrical manufacturer Siemens has been active in the Chinese market since the 1870s and established its first office in Shanghai in 1904. Focusing on marketing, the paper analyzes Siemens' business activities in China in the period from 1904 to 1937, and argues that the company exemplified a strategy of "glocalization," i.e. combining global business objectives and local adjustments. At the same time, the growing importance of international markets affected the development of the company as a whole. Referring to the contributions of "product," "price, "place" and "promotion" to the enterprise's development, this paper emphasizes the close connection between marketing and internationalization.

  13. Investigations of radial electric field and global circulation layer in limiter tokamaks

    International Nuclear Information System (INIS)

    Zagorski, R.; Gerhauser, H.; Lehnen, M.; Loarer, T.

    2002-01-01

    An updated version of the 2D multifluid code TECXY is used to study the radial electric field structure and the appearance of a global circulation layer (GCL) inside the separatrix of the limiter tokamaks TEXTOR-94 and Tore-Supra-CIEL. The dependence of the driving forces on device geometry, limiter position, magnetic field orientation, impurity content and other parameters is investigated. The centrifugal force in the vicinity of the limiter head always determines the direction of the poloidal velocity in the GCL. There is good agreement with experimentally measured profiles of the poloidal velocity at the TEXTOR low field side. (orig.)

  14. Robustness of edge states in topological quantum dots against global electric field

    Science.gov (United States)

    Qu, Jin-Xian; Zhang, Shu-Hui; Liu, Ding-Yang; Wang, Ping; Yang, Wen

    2017-07-01

    The topological insulator has attracted increasing attention as a new state of quantum matter featured by the symmetry-protected edge states. Although the qualitative robustness of the edge states against local perturbations has been well established, it is not clear how these topological edge states respond quantitatively to a global perturbation. Here, we study the response of topological edge states in a HgTe quantum dot to an external in-plane electric field—a paradigmatic global perturbation in solid-state environments. We find that the stability of the topological edge state could be larger than that of the ground bulk state by several orders of magnitudes. This robustness may be verified by standard transport measurements in the Coulomb blockage regime. Our work may pave the way towards utilizing these topological edge states as stable memory devices for charge and/or spin information and stable emitter of single terahertz photons or entangled terahertz photon pairs for quantum communication.

  15. Climate impacts on hydropower and consequences for global electricity supply investment needs

    Energy Technology Data Exchange (ETDEWEB)

    Turner, Sean W. D.; Hejazi, Mohamad; Kim, Son H.; Clarke, Leon; Edmonds, Jae

    2017-12-01

    Recent progress in global scale hydrological and dam modeling has allowed for the study of climate change impacts on global hydropower production. Here we explore the possible consequences of these impacts for the electricity supply sector. Regional hydropower projections are developed for two emissions scenarios by forcing a coupled global hydrological and dam model with downscaled, bias-corrected climate realizations derived from sixteen general circulation models. Consequent impacts on power sector composition and associated emissions and investment costs are explored using the Global Change Assessment Model (GCAM). Changes in hydropower generation resulting from climate change can shift power demands onto and away from carbon intensive technologies, resulting in significant impacts on power sector CO2 emissions for certain world regions—primarily those located in Latin America, as well as Canada and parts of Europe. Reduced impacts of climate change on hydropower production under a low emissions scenario coincide with increased costs of marginal power generating capacity—meaning impacts on power sector investment costs are similar for high and low emissions scenarios. Individual countries where impacts on investment costs imply significant risks or opportunities are identified.

  16. Workers' exposure to electric fields during the task 'maintenance of an operating device of circuit breaker from a service platform' at 110-kV substations.

    Science.gov (United States)

    Korpinen, Leena; Pääkkönen, Rauno

    2018-02-26

    The objective of the study was to investigate occupational exposure to electric fields during the task 'maintenance of an operating device of circuit breaker from a service platform' at 110-kV substations. The aim was also to compare the results to Directive 2013/35/EU. At 16 substations, 255 electric field measurements were performed. The highest mean value of the electric fields was 9.6 kV⋅m -1 . At 63% of substations the maximum values were over 10.0 kV⋅m -1 , and at 31% of the substations the 75th percentiles were over 10.0 kV⋅m -1 , which is the low action level (AL) according to Directive 2013/35/EU. All measured values were below the high AL (20.0 kV⋅m -1 ). In the future, it is important to take into account that the measurements were only taken at Finnish 110-kV substations; therefore, it is not possible to generalize these results to other countries and different types of substations.

  17. Anterior wrist and medial malleolus: the optimal sites for tissue selection in electric death through hand-to-foot circuit pathway.

    Science.gov (United States)

    Xu, Guangtao; Su, Ruibing; Lv, Junyao; Lai, Xiaoping; Li, Xianxian; Wu, Jiayan; Hu, Bo; Xu, Long; Shen, Ruilin; Gu, Jiang; Yu, Xiaojun

    2017-03-01

    Specific morphological changes may be absent in some cases of electrocution shocked by the voltage of 220 V or lower. In this study, we attempted to demonstrate that the anterior wrist and medial malleolus were the optimal sites with promising and significant changes in electric death through the hand-to-foot circuit pathway. We established an electric shock rat model and observed histopathologic changes in the anterior wrist and medial malleolus. The results showed that the current intensities in the left anterior wrist and right medial malleolus were remarkably higher than those in the other sites, and the nuclei long/short (L/S) axis ratios of the arterial endotheliocyte and the skeletal muscle cell in these two areas were significantly higher than those in other parts of the body. These findings suggested that the anterior wrist and/or medial malleolus soft tissues as the narrowest parts of the limbs could be used as promising and useful sites for the assessment of electrical shock death, especially in forensic pathologic evaluation.

  18. Evolution of short circuit levels in the National Electric System, years 2007 to 2011; Evolucion de los niveles de cortocircuito del Sistema Electrico Nacional, anos 2007 al 2011

    Energy Technology Data Exchange (ETDEWEB)

    Quintana Castaneda, J; Reyes Escobedo, G [Instituto de Investigaciones Electricas (Mexico)]. E-mails: jqc@iie.org.mx; gustavo.reyes@iie.org.mx; Ibarra Romo, F.G. [Comision Federal de Electricidad (Mexico)]. E-mail: federico.ibarra@cfe.gob.mx

    2013-03-15

    The present document shows an analysis of 2011 short-circuit levels on the different nodes (substations) that integrate the National Electric System. This analysis presents the figures of short-circuit levels on past years, stating on 2007, with the purpose of detecting the variation on each one of these nodes and identify the cases that because it's high levels are considered as critical nodes of the transmission system. At the end of the analysis some recommendations to minimize the potential risks are given on those substations classified as critical nodes. [Spanish] En este documento se expone un analisis de los niveles de cortocircuito que se presentaron en el 2011 en los distintos nodos (subestaciones) que conforman la red del Sistema Electrico Nacional (SEN). Este analisis muestra las cifras de los niveles de cortocircuito que se han presentado desde el ano 2007, a fin de estudiar el comportamiento y evolucion que han tenido los nodos de la red electrica, identificando aquellos puntos que por sus altos niveles de cortocircuito se consideran como nodos criticos. En la parte final del analisis se dan algunas recomendaciones para disminuir los riesgos que se pudieran presentar en aquellas subestaciones clasificadas como nodos criticos.

  19. Metallurgical features of the formation of a solid-phase metal joint upon electric-circuit heating

    Science.gov (United States)

    Latypov, R. A.; Bulychev, V. V.; Zybin, I. N.

    2017-06-01

    The thermodynamic conditions of formation of a joint between metals using the solid-phase methods of powder metallurgy, welding, and deposition of functional coatings upon electric-current heating of the surfaces to be joined are studied. Relations are obtained to quantitatively estimate the critical sizes of the circular and linear active centers that result in the formation of stable bonding zones.

  20. Circuital characteristics and radiation properties of an UWB electric-magnetic planar antenna for Ku-band applications

    NARCIS (Netherlands)

    Haider, S.N.; Caratelli, D.; Yarovoy, A.G.

    2013-01-01

    A planar, directive antenna with large fractional bandwidth is introduced in this paper. A detailed discussion on the proposed antenna topology and its architecture is reported. The proposed element is a combination of a patch and a loop radiator. A proper combination of the electric field radiator

  1. Nanosecond pulsed electric fields (nsPEFs) low cost generator design using power MOSFET and Cockcroft-Walton multiplier circuit as high voltage DC source

    International Nuclear Information System (INIS)

    Sulaeman, M. Y.; Widita, R.

    2014-01-01

    Purpose: Non-ionizing radiation therapy for cancer using pulsed electric field with high intensity field has become an interesting field new research topic. A new method using nanosecond pulsed electric fields (nsPEFs) offers a novel means to treat cancer. Not like the conventional electroporation, nsPEFs able to create nanopores in all membranes of the cell, including membrane in cell organelles, like mitochondria and nucleus. NsPEFs will promote cell death in several cell types, including cancer cell by apoptosis mechanism. NsPEFs will use pulse with intensity of electric field higher than conventional electroporation, between 20–100 kV/cm and with shorter duration of pulse than conventional electroporation. NsPEFs requires a generator to produce high voltage pulse and to achieve high intensity electric field with proper pulse width. However, manufacturing cost for creating generator that generates a high voltage with short duration for nsPEFs purposes is highly expensive. Hence, the aim of this research is to obtain the low cost generator design that is able to produce a high voltage pulse with nanosecond width and will be used for nsPEFs purposes. Method: Cockcroft-Walton multiplier circuit will boost the input of 220 volt AC into high voltage DC around 1500 volt and it will be combined by a series of power MOSFET as a fast switch to obtain a high voltage with nanosecond pulse width. The motivation using Cockcroft-Walton multiplier is to acquire a low-cost high voltage DC generator; it will use capacitors and diodes arranged like a step. Power MOSFET connected in series is used as voltage divider to share the high voltage in order not to damage them. Results: This design is expected to acquire a low-cost generator that can achieve the high voltage pulse in amount of −1.5 kV with falltime 3 ns and risetime 15 ns into a 50Ω load that will be used for nsPEFs purposes. Further detailed on the circuit design will be explained at presentation

  2. 49 CFR 236.721 - Circuit, control.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, control. 236.721 Section 236.721..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.721 Circuit, control. An electrical circuit between a source of electric energy and a device which it operates. ...

  3. Circuit analysis with Multisim

    CERN Document Server

    Baez-Lopez, David

    2011-01-01

    This book is concerned with circuit simulation using National Instruments Multisim. It focuses on the use and comprehension of the working techniques for electrical and electronic circuit simulation. The first chapters are devoted to basic circuit analysis.It starts by describing in detail how to perform a DC analysis using only resistors and independent and controlled sources. Then, it introduces capacitors and inductors to make a transient analysis. In the case of transient analysis, it is possible to have an initial condition either in the capacitor voltage or in the inductor current, or bo

  4. Extra high speed modified Lundell alternator parameters and open/short-circuit characteristics from global 3D-FE magnetic field solutions

    Science.gov (United States)

    Wang, R.; Demerdash, N. A.

    1992-06-01

    The combined magnetic vector potential - magnetic scalar potential method of computation of 3D magnetic fields by finite elements, introduced in a companion paper, is used for global 3D field analysis and machine performance computations under open-circuit and short-circuit conditions for an example 14.3 kVA modified Lundell alternator, whose magnetic field is of intrinsic 3D nature. The computed voltages and currents under these machine test conditions were verified and found to be in very good agreement with corresponding test data. Results of use of this modelling and computation method in the study of a design alteration example, in which the stator stack length of the example alternator is stretched in order to increase voltage and volt-ampere rating, are given here. These results demonstrate the inadequacy of conventional 2D-based design concepts and the imperative of use of this type of 3D magnetic field modelling in the design and investigation of such machines.

  5. Extra high speed modified Lundell alternator parameters and open/short-circuit characteristics from global 3D-FE magnetic field solutions

    Science.gov (United States)

    Wang, R.; Demerdash, N. A.

    1992-01-01

    The combined magnetic vector potential - magnetic scalar potential method of computation of 3D magnetic fields by finite elements, introduced in a companion paper, is used for global 3D field analysis and machine performance computations under open-circuit and short-circuit conditions for an example 14.3 kVA modified Lundell alternator, whose magnetic field is of intrinsic 3D nature. The computed voltages and currents under these machine test conditions were verified and found to be in very good agreement with corresponding test data. Results of use of this modelling and computation method in the study of a design alteration example, in which the stator stack length of the example alternator is stretched in order to increase voltage and volt-ampere rating, are given here. These results demonstrate the inadequacy of conventional 2D-based design concepts and the imperative of use of this type of 3D magnetic field modelling in the design and investigation of such machines.

  6. A globally nonsingular quaternion-based formulation for all-electric satellite trajectory optimization

    Science.gov (United States)

    Libraro, Paola

    The general electric propulsion orbit-raising maneuver of a spacecraft must contend with four main limiting factors: the longer time of flight, multiple eclipses prohibiting continuous thrusting, long exposure to radiation from the Van Allen belt and high power requirement of the electric engines. In order to optimize a low-thrust transfer with respect to these challenges, the choice of coordinates and corresponding equations of motion used to describe the kinematical and dynamical behavior of the satellite is of critical importance. This choice can potentially affect the numerical optimization process as well as limit the set of mission scenarios that can be investigated. To increase the ability to determine the feasible set of mission scenarios able to address the challenges of an all-electric orbit-raising, a set of equations free of any singularities is required to consider a completely arbitrary injection orbit. For this purpose a new quaternion-based formulation of a spacecraft translational dynamics that is globally nonsingular has been developed. The minimum-time low-thrust problem has been solved using the new set of equations of motion inside a direct optimization scheme in order to investigate optimal low-thrust trajectories over the full range of injection orbit inclinations between 0 and 90 degrees with particular focus on high-inclinations. The numerical results consider a specific mission scenario in order to analyze three key aspects of the problem: the effect of the initial guess on the shape and duration of the transfer, the effect of Earth oblateness on transfer time and the role played by, radiation damage and power degradation in all-electric minimum-time transfers. Finally trade-offs between mass and cost savings are introduced through a test case.

  7. Open circuit V-I characteristics of a coreless ironless electric generator for low density wind power generation

    Science.gov (United States)

    Razali, Akhtar; Rahman, Fadhlur; Azlan, Syaiful; Razali Hanipah, Mohd; Azri Hizami, Mohd

    2018-04-01

    Cogging is an attraction of magnetism between permanent magnets and soft ironcore lamination in a conventional electric ironcore generator. The presence of cog in the generator is seen somehow restricted the application of the generator in an application where low rotational torque is required. Cog torque requires an additional input power to overcome, hence became one of the power loss sources. With the increasing of power output, the cogging is also proportionally increased. This leads to the increasing of the supplied power of the driver motor to overcome the cog. Therefore, this research is embarked to study fundamentally about the possibility of removing ironcore lamination in an electric generator. This research deals with removal of ironcore lamination in electric generator to eliminate cog torque. A confinement technique is proposed to confine and focus magnetic flux by introducing opposing permanent magnets arrangement. The concept is then fabricated and experimentally validated to qualify its no-load characteristics. The rotational torque and power output are measured and efficiency is then analyzed. Results indicated that the generator produced RMS voltage of 416VAC at rotational speed of 1762 RPM. Torque required to rotate the generator was at 2Nm for various rotational speed. The generator has shown 30% lesser rotational torque compared to the conventional ironcore type generator due to the absent of cogging torque in the system. Lesser rotational torque required to rotate has made this type of generator has a potential to be used for low wind density wind turbine application.

  8. Electrical principles 3 checkbook

    CERN Document Server

    Bird, J O

    2013-01-01

    Electrical Principles 3 Checkbook aims to introduce students to the basic electrical principles needed by technicians in electrical engineering, electronics, and telecommunications.The book first tackles circuit theorems, single-phase series A.C. circuits, and single-phase parallel A.C. circuits. Discussions focus on worked problems on parallel A.C. circuits, worked problems on series A.C. circuits, main points concerned with D.C. circuit analysis, worked problems on circuit theorems, and further problems on circuit theorems. The manuscript then examines three-phase systems and D.C. transients

  9. Preparation of hierarchical porous carbon from waste printed circuit boards for high performance electric double-layer capacitors

    Science.gov (United States)

    Du, Xuan; Wang, Li; Zhao, Wei; Wang, Yi; Qi, Tao; Li, Chang Ming

    2016-08-01

    Renewable clean energy and resources recycling have become inevitable choices to solve worldwide energy shortages and environmental pollution problems. It is a great challenge to recycle tons of waste printed circuit boards (PCB) produced every year for clean environment while creating values. In this work, low cost, high quality activated carbons (ACs) were synthesized from non-metallic fractions (NMF) of waste PCB to offer a great potential for applications of electrochemical double-layer capacitors (EDLCs). After recovering metal from waste PCB, hierarchical porous carbons were produced from NMF by carbonization and activation processes. The experimental results exhibit that some pores were formed after carbonization due to the escape of impurity atoms introduced by additives in NMF. Then the pore structure was further tailored by adjusting the activation parameters. Roles of micropores and non-micropores in charge storage were investigated when the hierarchical porous carbons were applied as electrode of EDLCs. The highest specific capacitance of 210 F g-1 (at 50 mA g-1) and excellent rate capability were achieved when the ACs possessing a proper micropores/non-micropores ratio. This work not only provides a promising method to recycle PCB, but also investigates the structure tailoring arts for a rational hierarchical porous structure in energy storage/conversion.

  10. Optimizing the operating parameters of corona electrostatic separation for recycling waste scraped printed circuit boards by computer simulation of electric field.

    Science.gov (United States)

    Li, Jia; Lu, Hongzhou; Liu, Shushu; Xu, Zhenming

    2008-05-01

    The printed circuit board (PCB) has a metal content of nearly 28% metal, including an abundance of nonferrous metals such as copper, lead, and tin. The purity of precious metals in PCBs is more than 10 times that of rich-content minerals. Therefore, the recycling of PCBs is an important subject, not only from the viewpoint of waste treatment, but also with respect to the recovery of valuable materials. Compared with traditional process the corona electrostatic separation (CES) had no waste water or gas during the process and it had high productivity with a low-energy cost. In this paper, the roll-type corona electrostatic separator was used to separate metals and nonmetals from scraped waste PCBs. The software MATLAB was used to simulate the distribution of electric field in separating space. It was found that, the variations of parameters of electrodes and applied voltages directly influenced the distribution of electric field. Through the correlation of simulated and experimental results, the good separation results were got under the optimized operating parameter: U=20-30 kV, L=L(1)=L(2)=0.21 m, R(1)=0.114, R(2)=0.019 m, theta(1)=20 degrees and theta(2)=60 degrees .

  11. Global solar energy radiation in relation with electricity supply in Romania

    International Nuclear Information System (INIS)

    Zoran, Maria

    2001-01-01

    Solar energy is one of the most viable source of renewable energy being both clean and nonpolluting. Spiraling energy use and other human activities have led to measurable effects upon the global environment and climatic changes. There is increasing international concern particularly in the areas of global warming owing to the increase of carbon dioxide (CO 2 ) in the atmosphere and of other greenhouse gases as sulfur dioxide (SO 2 ), oxides of nitrogen (NOx), hydrogen sulfide H 2 S, diethyl sulfide (DMS), chlorofluorocarbons (CFCs), methane CH 4 , as well in the effect of depletion of ozone (O 3 ) layer in the stratosphere. Climatological and global solar radiation analysis for some Romanian zones with great solar energy potential are presented. Remote sensing data provided by satellites are used for radiative fluxes monitoring and solar energy mapping as well as for solar energy use assessment. The realistic technical potential for solar energy applications in Romania is substantial, over 40000 TJyear -1 . As average energy global solar radiation in horizontal plane lies between 1100 and 1300 kWhm -2 year -1 , solar energy using for electrical power supply being a reliable alternative. More than one half of Romania's area has a range of insolation period between 1200 and 1500 hours year -1 , at an overall average daily irradiation of 1000 - 1200 kWh m -2 . The most favorable area in Romania is the North - Western part of Black Sea coast with an insolation period above 2300 hours year -1 . A small part 140 TJyear -1 are used profitably and almost 10% of the installed 10 6 m 2 of collector area, is still in operation. (author)

  12. An assessment of alternatives for replacing Freon 113 in bench type electrical circuit board cleaning at Fermi National Accelerator Laboratory

    International Nuclear Information System (INIS)

    Isakson, K.; Vessell, A.L.

    1994-07-01

    Fermilab is presently phasing out all solvents containing Freon-113 (CFC-113) as part of the continuing Waste Minimization Program. These solvents are used primarily in cleaning the flux off of electronic circuit boards after soldering, specifically in bench type work. Title VI of the Clean Air Act mandates a production phase-out for ozone depleting substances, like CFC-113, by the year 2000. Our study addresses this issue by evaluating and choosing alternative non-CFC solvents to replace the CFC-1 13 solvents at Fermilab. Several potential non-CFC cleaning solvents were tested. The evaluation took place in three parts: controlled experimental evaluation, chemical composition evaluation, and employee performed evaluation. First, we performed a controlled nine-step procedure with the potential solvents where each was evaluated in categories such as cleaning effectiveness, odor, residue, type of output and drying time. Next, we listed the chemical composition of each solvent. We noted which solvents contained hydrochlorofluorocarbons because they are targeted for phase-out in the future and will be recognized as interim solutions only. Finally, after preliminary testing, five solvents were chosen as the best options. These solvents were sent to be tested by Fermilab employees who use such materials. Their opinions are valuable not only because they are knowledgeable in this field, but also because they will be using the solvents chosen to replace the CFC-113 solvents. The results favored two ''best alternatives'': Safezone Solvent Flux Remover by Miller-Stephenson and E-Series CFC Free Flux-Off 2000 by Chemtech. Another possible solution also pursued is the no-clean solder option. In our study, we were not able to thoroughly investigate the many types of no-clean solders because of time and financial constraints. The testing that was done, however, showed that no-clean solder was a viable alternative in many cases

  13. 30 CFR 56.6402 - Deenergized circuits near detonators.

    Science.gov (United States)

    2010-07-01

    ... Electric Blasting § 56.6402 Deenergized circuits near detonators. Electrical distribution circuits within 50 feet of electric detonators at the blast site shall be deenergized. Such circuits need not be deenergized between 25 to 50 feet of the electric detonators if stray current tests, conducted as frequently...

  14. 30 CFR 57.6402 - Deenergized circuits near detonators.

    Science.gov (United States)

    2010-07-01

    ... Electric Blasting-Surface and Underground § 57.6402 Deenergized circuits near detonators. Electrical distribution circuits within 50 feet of electric detonators at the blast site shall be deenergized. Such circuits need not be deenergized between 25 to 50 feet of the electric detonators if stray current tests...

  15. Fair weather atmospheric electricity

    International Nuclear Information System (INIS)

    Harrison, R G

    2011-01-01

    Not long after Franklin's iconic studies, an atmospheric electric field was discovered in 'fair weather' regions, well away from thunderstorms. The origin of the fair weather field was sought by Lord Kelvin, through development of electrostatic instrumentation and early data logging techniques, but was ultimately explained through the global circuit model of C.T.R. Wilson. In Wilson's model, charge exchanged by disturbed weather electrifies the ionosphere, and returns via a small vertical current density in fair weather regions. New insights into the relevance of fair weather atmospheric electricity to terrestrial and planetary atmospheres are now emerging. For example, there is a possible role of the global circuit current density in atmospheric processes, such as cloud formation. Beyond natural atmospheric processes, a novel practical application is the use of early atmospheric electrostatic investigations to provide quantitative information on past urban air pollution.

  16. Electricity sequence control

    International Nuclear Information System (INIS)

    Shin, Heung Ryeol

    2010-03-01

    The contents of the book are introduction of control system, like classification and control signal, introduction of electricity power switch, such as push-button and detection switch sensor for induction type and capacitance type machinery for control, solenoid valve, expression of sequence and type of electricity circuit about using diagram, time chart, marking and term, logic circuit like Yes, No, and, or and equivalence logic, basic electricity circuit, electricity sequence control, added condition, special program control about choice and jump of program, motor control, extra circuit on repeat circuit, pause circuit in a conveyer, safety regulations and rule about classification of electricity disaster and protective device for insulation.

  17. Effect of global warming on willingness to pay for uninterrupted electricity supply in European nations

    Science.gov (United States)

    Cohen, Jed; Moeltner, Klaus; Reichl, Johannes; Schmidthaler, Michael

    2018-01-01

    Predicted changes in temperature and other weather events may damage the electricity grid and cause power outages. Understanding the costs of power outages and how these costs change over time with global warming can inform outage-mitigation-investment decisions. Here we show that across 19 EU nations the value of uninterrupted electricity supply is strongly related to local temperatures, and will increase as the climate warms. Bayesian hierarchical modelling of data from a choice experiment and respondent-specific temperature measures reveals estimates of willingness to pay (WTP) to avoid an hour of power outage between €0.32 and €1.86 per household. WTP varies on the basis of season and is heterogeneous between European nations. Winter outages currently cause larger per household welfare losses than summer outages per hour of outage. However, this dynamic will begin to shift under plausible future climates, with summer outages becoming substantially more costly and winter outages becoming slightly less costly on a per-household, per-hour basis.

  18. Power Deals. Mergers and acquisitions activity within the global electricity and gas market. 2010 Annual Review

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-02-15

    The global power deal market is finally seeing an upward trend in momentum from the lows reached in 2009, with the total deal value in the non-renewable electricity and gas sectors up 19% year on year from USD 97.6bn to USD 116bn in 2010 - a year which also saw an end to the deal stalemate in the US with a renewed deal flow that looks set to continue this year. Compared to the heady mountain of power deals transacted between 2005-2008, deal values remain low but conditions are in place for a return at least to the foothills of these peaks, according to PwC's annual Power Deals review. Globalisation of the power sector is moving forward on a number of fronts with, for example, companies looking at gaining a larger presence in growth markets, acquisitions of global network asset portfolios with strong international interest in infrastructure assets and signs of greater Chinese involvement, not just from grid companies but also independent power producers.

  19. Electrical, Magnetic, Thermal Modeling and Analysis of a 5000A Solid-State Switch Module and Its Application as a DC Circuit Breaker

    OpenAIRE

    Zhou, Xigen

    2005-01-01

    This dissertation presents a systematic design and demonstration of a novel solid-state DC circuit breaker. The mechanical circuit breaker is widely used in power systems to protect industrial equipment during fault or abnormal conditions. Compared with the slow and high-maintenance mechanical circuit breaker, the solid-state circuit breaker is capable of high-speed interruption of high currents without generating an arc, hence it is maintenance-free. Both the switch and the tripping unit ...

  20. Electricity: the new millennium. A global gathering of the new electric industry -- an unparalleled conference... for a unique moment in time

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2000-05-01

    'Electricity: The New Millennium' is a conference sponsored by four major industry associations -- Edison Electric Institute of the United States, the International Union of Producers of Electrical Energy in Europe, the Canadian Electricity Association and Japan's Federation of Electric Power Companies. The International Energy Agency and the host company, Hydro-Quebec, were also co-sponsors of this crucial and memorable event to provide company CEOs and other top executives of electric companies with opportunities to equip themselves with the facts and viewpoints essential to success in the restructured electrical business environment. The meeting and the accompanying exhibit took place in Montreal, Quebec, on June 18-21, 2000, and drew attendees and exhibitors from all over the world to discuss the radical changes that are affecting the industry in terms of the organization of production and delivery of electric power. Opportunities were also be provided to explore the challenges facing the industry on a global basis, including exploring ways to use emerging technologies for delivering the benefits of electric power to under-served regions of the world's population that has yet to enjoy the most basic quality of life improvements that electricity can afford. Critical issues sessions also explored issues such as building stronger customer relations, organizing and financing the industry's transition, mastering cultural change, the relationship between meeting society's goals and market forces, and transmission systems in transition. Commensurate with the vast range of topics, speakers and session leaders have been recruited from the ranks of chief executives of major energy companies from America to Zambia, government agencies, leaders of major power users, and industry associations. Also appended to this description of the conference are an exhibition floor plan,a directory of exhibitors, and a description of sponsoring organizations

  1. How are WEEE doing? A global review of the management of electrical and electronic wastes.

    Science.gov (United States)

    Ongondo, F O; Williams, I D; Cherrett, T J

    2011-04-01

    This paper presents and critically analyses the current waste electrical and electronic equipment (WEEE) management practices in various countries and regions. Global trends in (i) the quantities and composition of WEEE; and (ii) the various strategies and practices adopted by selected countries to handle, regulate and prevent WEEE are comprehensively examined. The findings indicate that for (i), the quantities of WEEE generated are high and/or on the increase. IT and telecommunications equipment seem to be the dominant WEEE being generated, at least in terms of numbers, in Africa, in the poorer regions of Asia and in Latin/South America. However, the paper contends that the reported figures on quantities of WEEE generated may be grossly underestimated. For (ii), with the notable exception of Europe, many countries seem to be lacking or are slow in initiating, drafting and adopting WEEE regulations. Handling of WEEE in developing countries is typified by high rate of repair and reuse within a largely informal recycling sector. In both developed and developing nations, the landfilling of WEEE is still a concern. It has been established that stockpiling of unwanted electrical and electronic products is common in both the USA and less developed economies. The paper also identifies and discusses four common priority areas for WEEE across the globe, namely: (i) resource depletion; (ii) ethical concerns; (iii) health and environmental issues; and (iv) WEEE takeback strategies. Further, the paper discusses the future perspectives on WEEE generation, treatment, prevention and regulation. Four key conclusions are drawn from this review: global amounts of WEEE will continue unabated for some time due to emergence of new technologies and affordable electronics; informal recycling in developing nations has the potential of making a valuable contribution if their operations can be changed with strict safety standards as a priority; the pace of initiating and enacting WEEE

  2. How are WEEE doing? A global review of the management of electrical and electronic wastes

    International Nuclear Information System (INIS)

    Ongondo, F.O.; Williams, I.D.; Cherrett, T.J.

    2011-01-01

    This paper presents and critically analyses the current waste electrical and electronic equipment (WEEE) management practices in various countries and regions. Global trends in (i) the quantities and composition of WEEE; and (ii) the various strategies and practices adopted by selected countries to handle, regulate and prevent WEEE are comprehensively examined. The findings indicate that for (i), the quantities of WEEE generated are high and/or on the increase. IT and telecommunications equipment seem to be the dominant WEEE being generated, at least in terms of numbers, in Africa, in the poorer regions of Asia and in Latin/South America. However, the paper contends that the reported figures on quantities of WEEE generated may be grossly underestimated. For (ii), with the notable exception of Europe, many countries seem to be lacking or are slow in initiating, drafting and adopting WEEE regulations. Handling of WEEE in developing countries is typified by high rate of repair and reuse within a largely informal recycling sector. In both developed and developing nations, the landfilling of WEEE is still a concern. It has been established that stockpiling of unwanted electrical and electronic products is common in both the USA and less developed economies. The paper also identifies and discusses four common priority areas for WEEE across the globe, namely: (i) resource depletion; (ii) ethical concerns; (iii) health and environmental issues; and (iv) WEEE takeback strategies. Further, the paper discusses the future perspectives on WEEE generation, treatment, prevention and regulation. Four key conclusions are drawn from this review: global amounts of WEEE will continue unabated for some time due to emergence of new technologies and affordable electronics; informal recycling in developing nations has the potential of making a valuable contribution if their operations can be changed with strict safety standards as a priority; the pace of initiating and enacting WEEE

  3. Global electric-field determination in the Earth's outer magnetosphere using charged particles. Progress Report No. 1, 1991

    International Nuclear Information System (INIS)

    Eastman, T.; Sheldon, R.; Hamilton, D.; Mcilwain, C.

    1992-03-01

    Although many properties of the Earth's magnetosphere have been measured and quantified in the past 30 years since it was discovered, one fundamental (for a zeroeth order magnetohydrodynamic (MHD) equilibrium) measurement was made infrequently and with poor spatial coverage: the global electric field. This oversight is in part due to the difficulty of measuring a plasma electric field, and in part due to the difficulty of measuring a plasma electric field, and in part due to the neglect of theorists. However, there is renewed interest in the convection electric field, since it has been realized that it is vital for understanding many aspects of the magnetosphere: the global MHD equilibrium, reconnection rates, Region 2 Birkeland currents, magnetosphere-ionosphere coupling, ring current and radiation belt transport, substorm injections, acceleration mechanisms, etc. Unfortunately the standard experimental methods have not been able to synthesize a global field (excepting the pioneering work of McIlwain's geostationary models), and we are left with an overly simplistic theoretical field, the Volland-Stern electric field mode. Again, single point measurements of the plasma pause were used to infer the appropriate amplitudes of the model, parameterized by Kp (Maynard and Chen, JGR 1975). Although this result was never intended to be the definitive electric field model, it has gone nearly unchanged for 15 years. However, the data sets being taken today require a great deal more accuracy than can be provided by the Volland-Stern model. Nor has the variability of the electric field shielding been properly addressed, although effects of penetrating magnetospheric electric fields has been seen in mid- and low-latitude ionospheric data sets. The growing interests in substorm dynamics also requires a much better assessment of the electric fields responsible for particle injections

  4. Magnonic logic circuits

    International Nuclear Information System (INIS)

    Khitun, Alexander; Bao Mingqiang; Wang, Kang L

    2010-01-01

    We describe and analyse possible approaches to magnonic logic circuits and basic elements required for circuit construction. A distinctive feature of the magnonic circuitry is that information is transmitted by spin waves propagating in the magnetic waveguides without the use of electric current. The latter makes it possible to exploit spin wave phenomena for more efficient data transfer and enhanced logic functionality. We describe possible schemes for general computing and special task data processing. The functional throughput of the magnonic logic gates is estimated and compared with the conventional transistor-based approach. Magnonic logic circuits allow scaling down to the deep submicrometre range and THz frequency operation. The scaling is in favour of the magnonic circuits offering a significant functional advantage over the traditional approach. The disadvantages and problems of the spin wave devices are also discussed.

  5. Integrated coherent matter wave circuits

    International Nuclear Information System (INIS)

    Ryu, C.; Boshier, M. G.

    2015-01-01

    An integrated coherent matter wave circuit is a single device, analogous to an integrated optical circuit, in which coherent de Broglie waves are created and then launched into waveguides where they can be switched, divided, recombined, and detected as they propagate. Applications of such circuits include guided atom interferometers, atomtronic circuits, and precisely controlled delivery of atoms. We report experiments demonstrating integrated circuits for guided coherent matter waves. The circuit elements are created with the painted potential technique, a form of time-averaged optical dipole potential in which a rapidly moving, tightly focused laser beam exerts forces on atoms through their electric polarizability. Moreover, the source of coherent matter waves is a Bose-Einstein condensate (BEC). Finally, we launch BECs into painted waveguides that guide them around bends and form switches, phase coherent beamsplitters, and closed circuits. These are the basic elements that are needed to engineer arbitrarily complex matter wave circuitry

  6. A Magnetic Circuit Demonstration.

    Science.gov (United States)

    Vanderkooy, John; Lowe, June

    1995-01-01

    Presents a demonstration designed to illustrate Faraday's, Ampere's, and Lenz's laws and to reinforce the concepts through the analysis of a two-loop magnetic circuit. Can be made dramatic and challenging for sophisticated students but is suitable for an introductory course in electricity and magnetism. (JRH)

  7. Virtual CO2 Emission Flows in the Global Electricity Trade Network.

    Science.gov (United States)

    Qu, Shen; Li, Yun; Liang, Sai; Yuan, Jiahai; Xu, Ming

    2018-05-14

    Quantifying greenhouse gas emissions due to electricity consumption is crucial for climate mitigation in the electric power sector. Current practices primarily use production-based emission factors to quantify emissions for electricity consumption, assuming production and consumption of electricity take place within the same region. The increasingly intensified cross-border electricity trade complicates the accounting for emissions of electricity consumption. This study employs a network approach to account for the flows in the whole electricity trade network to estimate CO 2 emissions of electricity consumption for 137 major countries/regions in 2014. Results show that in some countries, especially those in Europe and Southern Africa, the impacts of electricity trade on the estimation of emission factors and embodied emissions are significant. The changes made to emission factors by considering intergrid electricity trade can have significant implications for emission accounting and climate mitigation when multiplied by total electricity consumption of the corresponding countries/regions.

  8. Electrical Qualification of the Pre-production of Analogue Opto-Hybrid Circuits for the CMS Tracker Inner Barrel and Inner Disks.

    CERN Document Server

    Brunetti, Maria Teresa; Postolache, Vasile; Ricci, Daniel

    2003-01-01

    A pre-production of 50 analogue opto-hybrid (AOH) circuits to be used in the front-end electronics of the CMS tracker was extensively tested before the incoming start of the massive production. A total of 4000 AOHs are required for the tracker inner barrel (TIB) and inner disk (TID) construction. The electrical response of the TIB/TID AOH pre-production was tested at 25°C both for the static and dynamic behavior. A subset of five AOHs was cooled and tested at -10°C and -15°C. A passive thermal cycle test from -20°C to 25°C was done on a sample of 22 pre-production AOHs, including the previous subset, to measure the mechanical response at possible variations of the nominal tracker temperature of -10°C. Four AOHs from the subset were also kept at -15°C for 20 hours in order to check the long-term stability of the response. The measurements were obtained with the automatic test equip ment (ATE) built for the fast qualification during the massive AOH production and with a custom setup dedicat...

  9. 77 FR 14838 - General Electric-Hitachi Global Laser Enrichment LLC, Commercial Laser-Based Uranium Enrichment...

    Science.gov (United States)

    2012-03-13

    ... Laser Enrichment LLC, Commercial Laser-Based Uranium Enrichment Facility, Wilmington, North Carolina... a license to General Electric-Hitachi Global Laser Enrichment LLC (GLE or the applicant) to authorize construction of a laser-based uranium enrichment facility and possession and use of byproduct...

  10. Time domain analog circuit simulation

    NARCIS (Netherlands)

    Fijnvandraat, J.G.; Houben, S.H.M.J.; Maten, ter E.J.W.; Peters, J.M.F.

    2006-01-01

    Recent developments of new methods for simulating electric circuits are described. Emphasis is put on methods that fit existing datastructures for backward differentiation formulae methods. These methods can be modified to apply to hierarchically organized datastructures, which allows for efficient

  11. Power Deals. Mergers and acquisitions activity within the global electricity and gas market. 2006 Annual Review

    International Nuclear Information System (INIS)

    2007-01-01

    2006 was another recordbreaking year in the electricity and gas utilities sector. Total deal values shot through the record level set in 2005 to reach a dizzying USD 298.8bn. This is nearly seven times the USD 43bn level of transactions recorded in the sector only three years earlier in 2003. The rise is all the more astonishing as it comes in a year when deal activity from corporate US utility players plummeted. The sharp downturn in North America came as companies took stock of aggressive regulatory stances from some state regulators during a US midterm election year that coincided with the ending of rate freezes and reaction to the repeal of the Public Utilities Holding Company Act. North American electricity deal values by bidder fell 64% to USD 20.7bn, not far above the USD 16.7bn level of 2003. The picture in Europe and the Asia Pacific region was very different. Both regions recorded record levels of power deal activities as utility companies continued to strive for super regional'' scale. Deal activity in Europe was given extra momentum by the countdown to the July 2007 implementation of full retail market liberalisation. This report examines the rationale behind the overall trends and the key individual deals. We also highlight, in a series of deal dialogues throughout the report, some of the critical issues for companies engaging in deal activity within the sector drawing on our global experience as an adviser to players in major deals throughout the sector in all key power and gas markets. Looking to the future, the regulatory environment will play a key role in determining the course of deal activity. Companies entering into big deals need to be ready more than ever for the long haul. However, the underpinning momentum in the sector remains strong and this is likely to create continued buoyancy in the period ahead

  12. Power Deals. Mergers and acquisitions activity within the global electricity and gas market. 2006 Annual Review

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-01-15

    2006 was another recordbreaking year in the electricity and gas utilities sector. Total deal values shot through the record level set in 2005 to reach a dizzying USD 298.8bn. This is nearly seven times the USD 43bn level of transactions recorded in the sector only three years earlier in 2003. The rise is all the more astonishing as it comes in a year when deal activity from corporate US utility players plummeted. The sharp downturn in North America came as companies took stock of aggressive regulatory stances from some state regulators during a US midterm election year that coincided with the ending of rate freezes and reaction to the repeal of the Public Utilities Holding Company Act. North American electricity deal values by bidder fell 64% to USD 20.7bn, not far above the USD 16.7bn level of 2003. The picture in Europe and the Asia Pacific region was very different. Both regions recorded record levels of power deal activities as utility companies continued to strive for super regional'' scale. Deal activity in Europe was given extra momentum by the countdown to the July 2007 implementation of full retail market liberalisation. This report examines the rationale behind the overall trends and the key individual deals. We also highlight, in a series of deal dialogues throughout the report, some of the critical issues for companies engaging in deal activity within the sector drawing on our global experience as an adviser to players in major deals throughout the sector in all key power and gas markets. Looking to the future, the regulatory environment will play a key role in determining the course of deal activity. Companies entering into big deals need to be ready more than ever for the long haul. However, the underpinning momentum in the sector remains strong and this is likely to create continued buoyancy in the period ahead.

  13. Development of a global electricity supply model and investigation of electricity supply by renewable energies with a focus on energy storage requirements for Europe

    Energy Technology Data Exchange (ETDEWEB)

    Troendle, Tobias Wolfgang

    2014-12-12

    Electricity supply at present requires about 38% of the global primary energy demand and it is likely to rise further in the coming decades. Facing major problems, such as limited resources of fuels and an ongoing anthropogenic climate change, a sustainable electricity supply based on renewable energies is absolutely vital. Wind and solar power will play an extensive role in future supplies but require energy storage capacities to meet electricity demand. To investigate the relationship of power plant mix and required energy storage capacity, a computer model based on global weather data has been developed to enable the simulation of electricity supply scenarios by up to ten different power plant types for various regions. The focus of the investigation has been on the energy storage requirements of an electricity supply for Europe by wind and solar power. The minimum required energy storage capacity for a totally weather dependent electricity supply occurs at a ratio of 30% wind and 70% photovoltaic (PV) power plant capacity installed. Thus, the required energy storage capacity rises from a transition of to-day's electricity supply to the afore-mentioned 100% renewable wind and PV scenario exponentially to about 150 TWh (3.8% of the annual electricity demand). The installation of additional excess wind and PV power plant capacity was seen to be an efficient way to reduce the required energy storage. Already 10% excess capacity lead to a reduction by 50% of the required storage capacity. To use different storage technologies in an optimised way in terms of storage capacity and efficiency, the storage tasks can be separated into a daily and a seasonal usage. While the seasonal storage capacity has to be about two orders of magnitude larger than the required capacity of the storage for the daily cycle, the sum of stored energy during one year is almost equal for the long and short time storage. In summary, an electricity supply by wind and PV power was shown to

  14. Development of a global electricity supply model and investigation of electricity supply by renewable energies with a focus on energy storage requirements for Europe

    International Nuclear Information System (INIS)

    Troendle, Tobias Wolfgang

    2014-01-01

    Electricity supply at present requires about 38% of the global primary energy demand and it is likely to rise further in the coming decades. Facing major problems, such as limited resources of fuels and an ongoing anthropogenic climate change, a sustainable electricity supply based on renewable energies is absolutely vital. Wind and solar power will play an extensive role in future supplies but require energy storage capacities to meet electricity demand. To investigate the relationship of power plant mix and required energy storage capacity, a computer model based on global weather data has been developed to enable the simulation of electricity supply scenarios by up to ten different power plant types for various regions. The focus of the investigation has been on the energy storage requirements of an electricity supply for Europe by wind and solar power. The minimum required energy storage capacity for a totally weather dependent electricity supply occurs at a ratio of 30% wind and 70% photovoltaic (PV) power plant capacity installed. Thus, the required energy storage capacity rises from a transition of to-day's electricity supply to the afore-mentioned 100% renewable wind and PV scenario exponentially to about 150 TWh (3.8% of the annual electricity demand). The installation of additional excess wind and PV power plant capacity was seen to be an efficient way to reduce the required energy storage. Already 10% excess capacity lead to a reduction by 50% of the required storage capacity. To use different storage technologies in an optimised way in terms of storage capacity and efficiency, the storage tasks can be separated into a daily and a seasonal usage. While the seasonal storage capacity has to be about two orders of magnitude larger than the required capacity of the storage for the daily cycle, the sum of stored energy during one year is almost equal for the long and short time storage. In summary, an electricity supply by wind and PV power was shown to

  15. Sustainability of sources of electric generation: indicators and global qualification using fuzzy logic; Sustentabilidad de fuentes de generacion electrica: indicadores y calificacion global empleando logica difusa

    Energy Technology Data Exchange (ETDEWEB)

    Martin del Campo M, C.; Francois L, J L [Facultad de Ingenieria, UNAM, Laboratorio de Analisis en Ingenieria de Reactores Nucleares, Paseo Cuauhnahuac 8532, 62550 Jiutepec, Morelos (Mexico)

    2005-07-01

    A methodology developed to evaluate the sustainability of sources of electric generation but used in Mexico and in the World is presented. For it was applied one matrix of sustainability indicators that considers the principles and criteria of general sustainability as 'not exhaustion of natural resources', 'non production of non degradable waste', and 'not high sensibility to social and environmental factors'. The approaches to evaluate in a wide way these principles are numerous and to each approach associates an indicator, call sustainability indicator. The contribution of this work consists on the development of a methodology to qualify globally the sustainability of each option of electric generation, combining all the sustainability indicators. The methodology applies a system of diffuse control to build the function of global qualification of sustainability dependent of all the indicators. (Author)

  16. Sustainability of sources of electric generation: indicators and global qualification using fuzzy logic; Sustentabilidad de fuentes de generacion electrica: indicadores y calificacion global empleando logica difusa

    Energy Technology Data Exchange (ETDEWEB)

    Martin del Campo M, C.; Francois L, J.L. [Facultad de Ingenieria, UNAM, Laboratorio de Analisis en Ingenieria de Reactores Nucleares, Paseo Cuauhnahuac 8532, 62550 Jiutepec, Morelos (Mexico)]. e-mail: cmcm@fi-b.unam.mx

    2005-07-01

    A methodology developed to evaluate the sustainability of sources of electric generation but used in Mexico and in the World is presented. For it was applied one matrix of sustainability indicators that considers the principles and criteria of general sustainability as 'not exhaustion of natural resources', 'non production of non degradable waste', and 'not high sensibility to social and environmental factors'. The approaches to evaluate in a wide way these principles are numerous and to each approach associates an indicator, call sustainability indicator. The contribution of this work consists on the development of a methodology to qualify globally the sustainability of each option of electric generation, combining all the sustainability indicators. The methodology applies a system of diffuse control to build the function of global qualification of sustainability dependent of all the indicators. (Author)

  17. Fire protection electrical engineering

    International Nuclear Information System (INIS)

    Oh, Jung Min

    2000-03-01

    This book concentrates of electricity with current, voltage, power, ohms law, access of resistance, electrolytic analysis and battery, static on frictional electricity and electrostatic induction, coulomb's law, Gauss's law, condenser and capacity, magmatism on magnetic field and magnetic line of force, magnetic circuit, electromagnetic force, electromotive current, basic alternating current circuit, circuit network analysis, three-phase current, non-sinusoidal alternating current, transient phenomena, semiconductor, electric measurement on measurement over resistance, power, power rate and circuit tester, automatic control on introduction, term, classification, foundation of sequence control, logic circuit and basic logic circuit and electric equipment.

  18. Flexible mechanisms in the corporate greenhouse: implementation of the Kyoto Protocol and the globalization of the electric power industry

    Energy Technology Data Exchange (ETDEWEB)

    Schreuder, Y.; Sherry, C. [University of Delaware, Newark, DE (United States). Center for Energy and Environmental Policy

    2001-07-01

    The contradictions and unresolved tensions between economic globalization and climate change negotiations have added urgency to the climate change debate. The paper argues that the declining role of the nation state in the global economy and the increasing reach of transnational corporations throughout the world present a serious challenge to the environmental integrity and success of international environmental treaties such as the Kyoto Protocol. In particular efficacy and equity of the flexible mechanism under the Kyoto Protocol are questioned as illustrated by the patterns of Foreign Direct Investment (FDI) of the US electric power industry in the developing world. US FDI in the electric power sectors of developing countries supports continued carbon-intensive development patterns which will make the long-term goals of the Kyoto Protocol more difficult to achieve. Consequently, FDI raises questions about justifiability of giving credit to Annex I countries through CDM projects undertaken by transnational electric power corporations. 13 refs.

  19. Power Deals. Mergers and acquisitions activity within the global electricity and gas market. 2008 Annual Review

    International Nuclear Information System (INIS)

    2009-01-01

    2008 was the year in which power deal values came down from their record-breaking highs of the two preceding years as the financial crisis and a number of market uncertainties had a negative impact on deal activity. Nonetheless, total deal numbers leapt by 24% as companies concentrated on smaller deals and took advantage of new opportunities that arose in the changed market conditions. Europe was least affected by the downturn in deal values and accounted for over half of all bidder and target power deal value. In contrast, power deals in Australia, which had previously been a main motor of growing M and A activity in the Asia Pacific region, virtually stalled as uncertainty over new carbon emission policies combined with the financial crisis to deter deal flow. In North America, like Europe, big deals were fewer but underlying deal activity was comparable with previous years. This report examines the rationale behind the overall trends and the key individual deals. We also highlight, in a series of deal dialogues throughout the report, some of the critical issues for companies engaging in deal activity within the sector, drawing on our global experience as an adviser to players in major deals throughout the sector in all key electricity and gas utilities markets. Looking to the future, the easing of the financial crisis will be key to deal flow but the near-term outlook looks less robust than the recent past, especially as debt markets will be further constrained by calls from the public financing required to support government bail-out programmes. Set against this, the underlying imperatives of consolidation, supply security and capitalisation remain in place and will create increasing pent-up deal demand. A lower energy price environment will change the metrics for more expensive cleaner power assets, placing an even higher importance on the outcome of global climate talks and the run-up to the December 2009 UN Climate Summit in Copenhagen

  20. Power Deals. Mergers and acquisitions activity within the global electricity and gas market. 2008 Annual Review

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-01-15

    2008 was the year in which power deal values came down from their record-breaking highs of the two preceding years as the financial crisis and a number of market uncertainties had a negative impact on deal activity. Nonetheless, total deal numbers leapt by 24% as companies concentrated on smaller deals and took advantage of new opportunities that arose in the changed market conditions. Europe was least affected by the downturn in deal values and accounted for over half of all bidder and target power deal value. In contrast, power deals in Australia, which had previously been a main motor of growing M and A activity in the Asia Pacific region, virtually stalled as uncertainty over new carbon emission policies combined with the financial crisis to deter deal flow. In North America, like Europe, big deals were fewer but underlying deal activity was comparable with previous years. This report examines the rationale behind the overall trends and the key individual deals. We also highlight, in a series of deal dialogues throughout the report, some of the critical issues for companies engaging in deal activity within the sector, drawing on our global experience as an adviser to players in major deals throughout the sector in all key electricity and gas utilities markets. Looking to the future, the easing of the financial crisis will be key to deal flow but the near-term outlook looks less robust than the recent past, especially as debt markets will be further constrained by calls from the public financing required to support government bail-out programmes. Set against this, the underlying imperatives of consolidation, supply security and capitalisation remain in place and will create increasing pent-up deal demand. A lower energy price environment will change the metrics for more expensive cleaner power assets, placing an even higher importance on the outcome of global climate talks and the run-up to the December 2009 UN Climate Summit in Copenhagen.

  1. Atmospheric Electricity

    Science.gov (United States)

    Aplin, Karen; Fischer, Georg

    2018-02-01

    Electricity occurs in atmospheres across the Solar System planets and beyond, spanning spectacular lightning displays in clouds of water or dust, to more subtle effects of charge and electric fields. On Earth, lightning is likely to have existed for a long time, based on evidence from fossilized lightning strikes in ancient rocks, but observations of planetary lightning are necessarily much more recent. The generation and observations of lightning and other atmospheric electrical processes, both from within-atmosphere measurements, and spacecraft remote sensing, can be readily studied using a comparative planetology approach, with Earth as a model. All atmospheres contain charged molecules, electrons, and/or molecular clusters created by ionization from cosmic rays and other processes, which may affect an atmosphere's energy balance both through aerosol and cloud formation, and direct absorption of radiation. Several planets are anticipated to host a "global electric circuit" by analogy with the circuit occurring on Earth, where thunderstorms drive current of ions or electrons through weakly conductive parts of the atmosphere. This current flow may further modulate an atmosphere's radiative properties through cloud and aerosol effects. Lightning could potentially have implications for life through its effects on atmospheric chemistry and particle transport. It has been observed on many of the Solar System planets (Earth, Jupiter, Saturn, Uranus, and Neptune) and it may also be present on Venus and Mars. On Earth, Jupiter, and Saturn, lightning is thought to be generated in deep water and ice clouds, but discharges can be generated in dust, as for terrestrial volcanic lightning, and on Mars. Other, less well-understood mechanisms causing discharges in non-water clouds also seem likely. The discovery of thousands of exoplanets has recently led to a range of further exotic possibilities for atmospheric electricity, though lightning detection beyond our Solar System

  2. Resonance circuits for adiabatic circuits

    Directory of Open Access Journals (Sweden)

    C. Schlachta

    2003-01-01

    Full Text Available One of the possible techniques to reduces the power consumption in digital CMOS circuits is to slow down the charge transport. This slowdown can be achieved by introducing an inductor in the charging path. Additionally, the inductor can act as an energy storage element, conserving the energy that is normally dissipated during discharging. Together with the parasitic capacitances from the circuit a LCresonant circuit is formed.

  3. How much electricity can we save by using direct current circuits in homes? Understanding the potential for electricity savings and assessing feasibility of a transition towards DC powered buildings

    International Nuclear Information System (INIS)

    Glasgo, Brock; Azevedo, Inês Lima; Hendrickson, Chris

    2016-01-01

    Highlights: • DC distribution systems are analyzed using monitored appliance and solar PV data. • DC-distributed PV energy generates savings under real-world load and solar profiles. • Savings from direct-DC are generally not cost-effective in current markets. • Non-technical hurdles remain before DC can be widely adopted in US homes. - Abstract: Advances in semiconductor-based power electronics and growing direct current loads in buildings have led researchers to reconsider whether buildings should be wired with DC circuits to reduce power conversions and facilitate a transition to efficient DC appliances. The feasibility, energy savings, and economics of such systems have been assessed and proven in data centers and commercial buildings, but the outcomes are still uncertain for the residential sector. In this work, we assess the technical and economic feasibility of DC circuits using data for 120 traditionally-wired AC homes in Austin, Texas to understand the effect of highly variable demand profiles on DC-powered residences, using appliance-level use and solar generation data, and performing a Monte Carlo simulation to quantify costs and benefits. Results show site energy savings between 9% and 20% when solar PV is distributed to all home appliances. When battery storage for excess solar energy is considered, these savings increase to 14–25%. At present DC equipment prices, converting all equipment to DC causes levelized annual costs of electricity to homeowners to roughly double. However, by converting only homes’ air conditioning condensing units to DC, the costs of direct-DC are greatly reduced and home site energy savings of 7–16% are generated. In addition to quantifying savings, we find major nontechnical barriers to implementing direct-DC in homes. These include a lack of standards for such systems, a relatively small market for DC appliances and components, utility programs designed for AC power, and a workforce unfamiliar with DC

  4. Identification of a new gene regulatory circuit involving B cell receptor activated signaling using a combined analysis of experimental, clinical and global gene expression data

    Science.gov (United States)

    Schrader, Alexandra; Meyer, Katharina; Walther, Neele; Stolz, Ailine; Feist, Maren; Hand, Elisabeth; von Bonin, Frederike; Evers, Maurits; Kohler, Christian; Shirneshan, Katayoon; Vockerodt, Martina; Klapper, Wolfram; Szczepanowski, Monika; Murray, Paul G.; Bastians, Holger; Trümper, Lorenz; Spang, Rainer; Kube, Dieter

    2016-01-01

    To discover new regulatory pathways in B lymphoma cells, we performed a combined analysis of experimental, clinical and global gene expression data. We identified a specific cluster of genes that was coherently expressed in primary lymphoma samples and suppressed by activation of the B cell receptor (BCR) through αIgM treatment of lymphoma cells in vitro. This gene cluster, which we called BCR.1, includes numerous cell cycle regulators. A reduced expression of BCR.1 genes after BCR activation was observed in different cell lines and also in CD10+ germinal center B cells. We found that BCR activation led to a delayed entry to and progression of mitosis and defects in metaphase. Cytogenetic changes were detected upon long-term αIgM treatment. Furthermore, an inverse correlation of BCR.1 genes with c-Myc co-regulated genes in distinct groups of lymphoma patients was observed. Finally, we showed that the BCR.1 index discriminates activated B cell-like and germinal centre B cell-like diffuse large B cell lymphoma supporting the functional relevance of this new regulatory circuit and the power of guided clustering for biomarker discovery. PMID:27166259

  5. Electrical and electronic principles

    CERN Document Server

    Knight, SA

    1988-01-01

    Electrical and Electronic Principles, 3 focuses on the principles involved in electrical and electronic circuits, including impedance, inductance, capacitance, and resistance.The book first deals with circuit elements and theorems, D.C. transients, and the series circuits of alternating current. Discussions focus on inductance and resistance in series, resistance and capacitance in series, power factor, impedance, circuit magnification, equation of charge, discharge of a capacitor, transfer of power, and decibels and attenuation. The manuscript then examines the parallel circuits of alternatin

  6. Resources transfer and centralization in Brazilian electrical sector: the reversion global reserve (RGR) and the guarantee global reserve (GGR); Centralizacao e transferencia de recursos no setor eletrico brasileiro: a reserva global de reversao (RGR) e a reserva global de garantia (RGG)

    Energy Technology Data Exchange (ETDEWEB)

    Souza Amaral Filho, J.B. de

    1991-12-31

    This dissertation makes the analysis of resources transfer and centralization in Brazilian electrical sector, through reversion global reserve (RGR) and guarantee global reserve (GGR). RGR and GGR are funds. RGR finances sectorial investments in electric power and GGR aims the supply of deficient concessionaires. Governmental investments and the results of this application are showing. (M.V.M.). 55 refs, 2 figs, 61 tabs.

  7. Resources transfer and centralization in Brazilian electrical sector: the reversion global reserve (RGR) and the guarantee global reserve (GGR); Centralizacao e transferencia de recursos no setor eletrico brasileiro: a reserva global de reversao (RGR) e a reserva global de garantia (RGG)

    Energy Technology Data Exchange (ETDEWEB)

    Souza Amaral Filho, J.B. de

    1992-12-31

    This dissertation makes the analysis of resources transfer and centralization in Brazilian electrical sector, through reversion global reserve (RGR) and guarantee global reserve (GGR). RGR and GGR are funds. RGR finances sectorial investments in electric power and GGR aims the supply of deficient concessionaires. Governmental investments and the results of this application are showing. (M.V.M.). 55 refs, 2 figs, 61 tabs.

  8. Energy balance of the global photovoltaic (PV) industry--is the PV industry a net electricity producer?

    Science.gov (United States)

    Dale, Michael; Benson, Sally M

    2013-04-02

    A combination of declining costs and policy measures motivated by greenhouse gas (GHG) emissions reduction and energy security have driven rapid growth in the global installed capacity of solar photovoltaics (PV). This paper develops a number of unique data sets, namely the following: calculation of distribution of global capacity factor for PV deployment; meta-analysis of energy consumption in PV system manufacture and deployment; and documentation of reduction in energetic costs of PV system production. These data are used as input into a new net energy analysis of the global PV industry, as opposed to device level analysis. In addition, the paper introduces a new concept: a model tracking energetic costs of manufacturing and installing PV systems, including balance of system (BOS) components. The model is used to forecast electrical energy requirements to scale up the PV industry and determine the electricity balance of the global PV industry to 2020. Results suggest that the industry was a net consumer of electricity as recently as 2010. However, there is a >50% that in 2012 the PV industry is a net electricity provider and will "pay back" the electrical energy required for its early growth before 2020. Further reducing energetic costs of PV deployment will enable more rapid growth of the PV industry. There is also great potential to increase the capacity factor of PV deployment. These conclusions have a number of implications for R&D and deployment, including the following: monitoring of the energy embodied within PV systems; designing more efficient and durable systems; and deploying PV systems in locations that will achieve high capacity factors.

  9. Electronic circuit encyclopedia 2

    International Nuclear Information System (INIS)

    Park, Sun Ho

    1992-10-01

    This book is composed of 15 chapters, which are amplification of weak signal and measurement circuit audio control and power amplification circuit, data transmission and wireless system, forwarding and isolation, signal converting circuit, counter and comparator, discriminator circuit, oscillation circuit and synthesizer, digital and circuit on computer image processing circuit, sensor drive circuit temperature sensor circuit, magnetic control and application circuit, motor driver circuit, measuring instrument and check tool and power control and stability circuit.

  10. Electronic circuit encyclopedia 2

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sun Ho

    1992-10-15

    This book is composed of 15 chapters, which are amplification of weak signal and measurement circuit audio control and power amplification circuit, data transmission and wireless system, forwarding and isolation, signal converting circuit, counter and comparator, discriminator circuit, oscillation circuit and synthesizer, digital and circuit on computer image processing circuit, sensor drive circuit temperature sensor circuit, magnetic control and application circuit, motor driver circuit, measuring instrument and check tool and power control and stability circuit.

  11. Long term energy and emission implications of a global shift to electricity-based public rail transportation system

    International Nuclear Information System (INIS)

    Chaturvedi, Vaibhav; Kim, Son H.

    2015-01-01

    With high reliance on light-duty vehicles in the present, the future of global transportation system is also geared towards private modes, which has significant energy and emission implications. Public transportation has been argued as an alternative strategy for meeting the rising transportation demands of the growing world, especially the poor, in a sustainable and energy efficient way. The present study analyzes an important yet under-researched question – what are the long-term energy and emission implications of an electric rail based passenger transportation system for meeting both long and short distance passenter transportation needs? We analyze a suite of electric rail share scenarios with and without climate policy. In the reference scenario, the transportation system will evolve towards dominance of fossil based light-duty vehicles. We find that an electric rail policy is more successful than an economy wide climate policy in reducing transport sector energy demand and emissions. Economy wide emissions however can only be reduced through a broader climate policy, the cost of which can be reduced by hundreds of billions of dollars across the century when implemented in combination with the transport sector focused electric rail policy. Moreover, higher share of electric rail enhances energy security for oil importing nations and reduces vehicular congestion and road infrastructure requirement as well. -- Highlights: •Economy wide carbon price policy will have little impact on transportation emissions. •Focused energy and emission mitigation policies required for transportation sector. •Large global shift towards electric rail based public transport is one possible option. •Transport sector focused policy will have marginal impact on total global emissions. •A combined transport sector and economy wide policy can reduce costs significantly

  12. CMOS digital integrated circuits a first course

    CERN Document Server

    Hawkins, Charles; Zarkesh-Ha, Payman

    2016-01-01

    This book teaches the fundamentals of modern CMOS technology and covers equal treatment to both types of MOSFET transistors that make up computer circuits; power properties of logic circuits; physical and electrical properties of metals; introduction of timing circuit electronics and introduction of layout; real-world examples and problem sets.

  13. The consumptive water footprint of electricity and heat: a global assessment

    NARCIS (Netherlands)

    Mekonnen, Mesfin; Gerbens-Leenes, Winnie; Hoekstra, Arjen Ysbert

    2015-01-01

    Water is essential for electricity and heat production. This study assesses the consumptive water footprint (WF) of electricity and heat generation per world region in the three main stages of the production chain, i.e. fuel supply, construction and operation. We consider electricity from power

  14. Arithmetic circuits for DSP applications

    CERN Document Server

    Stouraitis, Thanos

    2017-01-01

    Arithmetic Circuits for DSP Applications is a complete resource on arithmetic circuits for digital signal processing (DSP). It covers the key concepts, designs and developments of different types of arithmetic circuits, which can be used for improving the efficiency of implementation of a multitude of DSP applications. Each chapter includes various applications of the respective class of arithmetic circuits along with information on the future scope of research. Written for students, engineers, and researchers in electrical and computer engineering, this comprehensive text offers a clear understanding of different types of arithmetic circuits used for digital signal processing applications. The text includes contributions from noted researchers on a wide range of topics, including a review o circuits used in implementing basic operations like additions and multiplications; distributed arithmetic as a technique for the multiplier-less implementation of inner products for DSP applications; discussions on look ...

  15. Digital circuit boards mach 1 GHz

    CERN Document Server

    Morrison, Ralph

    2012-01-01

    A unique, practical approach to the design of high-speed digital circuit boards The demand for ever-faster digital circuit designs is beginning to render the circuit theory used by engineers ineffective. Digital Circuit Boards presents an alternative to the circuit theory approach, emphasizing energy flow rather than just signal interconnection to explain logic circuit behavior. The book shows how treating design in terms of transmission lines will ensure that the logic will function, addressing both storage and movement of electrical energy on these lines. It cove

  16. The dynamics of technology diffusion and the impacts of climate policy instruments in the decarbonisation of the global electricity sector

    International Nuclear Information System (INIS)

    Mercure, J.-F.; Pollitt, H.; Chewpreecha, U.; Salas, P.; Foley, A.M.; Holden, P.B.; Edwards, N.R.

    2014-01-01

    This paper presents an analysis of climate policy instruments for the decarbonisation of the global electricity sector in a non-equilibrium economic and technology diffusion perspective. Energy markets are driven by innovation, path-dependent technology choices and diffusion. However, conventional optimisation models lack detail on these aspects and have limited ability to address the effectiveness of policy interventions because they do not represent decision-making. As a result, known effects of technology lock-ins are liable to be underestimated. In contrast, our approach places investor decision-making at the core of the analysis and investigates how it drives the diffusion of low-carbon technology in a highly disaggregated, hybrid, global macroeconometric model, FTT:Power-E3MG. Ten scenarios to 2050 of the electricity sector in 21 regions exploring combinations of electricity policy instruments are analysed, including their climate impacts. We show that in a diffusion and path-dependent perspective, the impact of combinations of policies does not correspond to the sum of impacts of individual instruments: synergies exist between policy tools. We argue that the carbon price required to break the current fossil technology lock-in can be much lower when combined with other policies, and that a 90% decarbonisation of the electricity sector by 2050 is affordable without early scrapping. - Highlights: • Policy scenarios for decarbonising of the global electricity sector by 90%. • Strong synergies exist between different energy policy instruments. • Carbon pricing not a sufficient policy instrument for large emissions reductions. • Improved agent behaviour assumptions for energy modelling beyond cost-optimisation

  17. Does electricity consumption panel Granger cause GDP? A new global evidence

    Energy Technology Data Exchange (ETDEWEB)

    Narayan, Paresh Kumar [School of Accounting, Economics and Finance, Faculty of Business and Economics, Deakin University, Melbourne (Australia); Narayan, Seema [School of Economics, Finance, and Marketing, RMIT University, Melbourne (Australia); Popp, Stephan [Department of Economics, University of Duisburg-Essen (Germany)

    2010-10-15

    The goal of this paper is to undertake a panel data investigation of long-run Granger causality between electricity consumption and real GDP for seven panels, which together consist of 93 countries. We use a new panel causality test and find that in the long-run both electricity consumption and real GDP have a bidirectional Granger causality relationship except for the Middle East where causality runs only from GDP to electricity consumption. Finally, for the G6 panel the estimates reveal a negative sign effect, implying that increasing electricity consumption in the six most industrialised nations will reduce GDP. (author)

  18. Globalization

    Directory of Open Access Journals (Sweden)

    Tulio Rosembuj

    2006-12-01

    Full Text Available There is no singular globalization, nor is the result of an individual agent. We could start by saying that global action has different angles and subjects who perform it are different, as well as its objectives. The global is an invisible invasion of materials and immediate effects.

  19. Globalization

    OpenAIRE

    Tulio Rosembuj

    2006-01-01

    There is no singular globalization, nor is the result of an individual agent. We could start by saying that global action has different angles and subjects who perform it are different, as well as its objectives. The global is an invisible invasion of materials and immediate effects.

  20. Electrical energy in France in 2009

    International Nuclear Information System (INIS)

    2009-12-01

    The figures presented on this document account for the electricity flows recorded in Metropolitan France, including Corsica. Contents: national consumption; physical exchanges with foreign countries; electrical energy balance in France in 2009; net generation; noteworthy data for the year 2009 (daily maximum values of national consumption, thermal generation, hydro-electric generation, wind generation and balance of physical exchanges); electricity market: cross-borders contractual exchanges, balance responsible entities (Energy amount exchanged between balance responsible entities through the block exchange notifications), balancing mechanism (global amount of energy activated upwards and downwards), daily market coupling; power facilities: generating facilities in France (Nuclear, Fossil fuel thermal, Hydro-electric, Wind and Other renewable energy sources), transmission lines owned by RTE (circuit length in operation), transmission - transformers owned by RTE (installed capacity in operation); main transmission facilities commissioned during the year 2009 (substations connected to the RTE network and new or refurbished circuits)

  1. The role of nuclear power in the global electric power system

    International Nuclear Information System (INIS)

    Sidorenko, V.A.; Chernilin, Yu.F.

    1992-01-01

    Basic conclusions and recommendations developed in the process of preparing and conducting the symposium discussed are presented. All methods of electric power production, their prospects and effects on man and environment were discussed during the symposium. This paper is devoted mainly to nuclear power engineering only, its prospects and possible role in general electric power generation

  2. The Simulation Computer Based Learning (SCBL) for Short Circuit Multi Machine Power System Analysis

    Science.gov (United States)

    Rahmaniar; Putri, Maharani

    2018-03-01

    Strengthening Competitiveness of human resources become the reply of college as a conductor of high fomal education. Electrical Engineering Program UNPAB (Prodi TE UNPAB) as one of the department of electrical engineering that manages the field of electrical engineering expertise has a very important part in preparing human resources (HR), Which is required by where graduates are produced by DE UNPAB, Is expected to be able to compete globally, especially related to the implementation of Asean Economic Community (AEC) which requires the active participation of graduates with competence and quality of human resource competitiveness. Preparation of HR formation Competitive is done with the various strategies contained in the Seven (7) Higher Education Standard, one part of which is the implementation of teaching and learning process in Electrical system analysis with short circuit analysis (SCA) This course is a course The core of which is the basis for the competencies of other subjects in the advanced semester at Development of Computer Based Learning model (CBL) is done in the learning of interference analysis of multi-machine short circuit which includes: (a) Short-circuit One phase, (B) Two-phase Short Circuit Disruption, (c) Ground Short Circuit Disruption, (d) Short Circuit Disruption One Ground Floor Development of CBL learning model for Electrical System Analysis course provides space for students to be more active In learning in solving complex (complicated) problems, so it is thrilling Ilkan flexibility of student learning how to actively solve the problem of short-circuit analysis and to form the active participation of students in learning (Student Center Learning, in the course of electrical power system analysis.

  3. A new approach of optimization procedure for superconducting integrated circuits

    International Nuclear Information System (INIS)

    Saitoh, K.; Soutome, Y.; Tarutani, Y.; Takagi, K.

    1999-01-01

    We have developed and tested a new circuit simulation procedure for superconducting integrated circuits which can be used to optimize circuit parameters. This method reveals a stable operation region in the circuit parameter space in connection with the global bias margin by means of a contour plot of the global bias margin versus the circuit parameters. An optimal set of parameters with margins larger than these of the initial values has been found in the stable region. (author)

  4. Analysis of Surface Electric Field Measurements from an Array of Electric Field Mills

    Science.gov (United States)

    Lucas, G.; Thayer, J. P.; Deierling, W.

    2016-12-01

    Kennedy Space Center (KSC) has operated an distributed array of over 30 electric field mills over the past 18 years, providing a unique data set of surface electric field measurements over a very long timespan. In addition to the electric field instruments there are many meteorological towers around KSC that monitor the local meteorological conditions. Utilizing these datasets we have investigated and found unique spatial and temporal signatures in the electric field data that are attributed to local meteorological effects and the global electric circuit. The local and global scale influences on the atmospheric electric field will be discussed including the generation of space charge from the ocean surf, local cloud cover, and a local enhancement in the electric field that is seen at sunrise.

  5. High Performance Electrical Modeling and Simulation Verification Test Suite - Tier I; TOPICAL

    International Nuclear Information System (INIS)

    SCHELLS, REGINA L.; BOGDAN, CAROLYN W.; WIX, STEVEN D.

    2001-01-01

    This document describes the High Performance Electrical Modeling and Simulation (HPEMS) Global Verification Test Suite (VERTS). The VERTS is a regression test suite used for verification of the electrical circuit simulation codes currently being developed by the HPEMS code development team. This document contains descriptions of the Tier I test cases

  6. Globalization

    OpenAIRE

    Andru?cã Maria Carmen

    2013-01-01

    The field of globalization has highlighted an interdependence implied by a more harmonious understanding determined by the daily interaction between nations through the inducement of peace and the management of streamlining and the effectiveness of the global economy. For the functioning of the globalization, the developing countries that can be helped by the developed ones must be involved. The international community can contribute to the institution of the development environment of the gl...

  7. Differential transimpedance amplifier circuit for correlated differential amplification

    Science.gov (United States)

    Gresham, Christopher A [Albuquerque, NM; Denton, M Bonner [Tucson, AZ; Sperline, Roger P [Tucson, AZ

    2008-07-22

    A differential transimpedance amplifier circuit for correlated differential amplification. The amplifier circuit increase electronic signal-to-noise ratios in charge detection circuits designed for the detection of very small quantities of electrical charge and/or very weak electromagnetic waves. A differential, integrating capacitive transimpedance amplifier integrated circuit comprising capacitor feedback loops performs time-correlated subtraction of noise.

  8. 30 CFR 56.12065 - Short circuit and lightning protection.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Short circuit and lightning protection. 56... Electricity § 56.12065 Short circuit and lightning protection. Powerlines, including trolley wires, and telephone circuits shall be protected against short circuits and lightning. ...

  9. 30 CFR 57.12065 - Short circuit and lightning protection.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Short circuit and lightning protection. 57... MINES Electricity Surface Only § 57.12065 Short circuit and lightning protection. Powerlines, including trolley wires, and telephone circuits shall be protected against short circuits and lightning. ...

  10. 49 CFR 236.786 - Principle, closed circuit.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Principle, closed circuit. 236.786 Section 236.786 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Principle, closed circuit. The principle of circuit design where a normally energized electric circuit which...

  11. Estimating the global public health implications of electricity and coal consumption.

    Science.gov (United States)

    Gohlke, Julia M; Thomas, Reuben; Woodward, Alistair; Campbell-Lendrum, Diarmid; Prüss-Üstün, Annette; Hales, Simon; Portier, Christopher J

    2011-06-01

    The growing health risks associated with greenhouse gas emissions highlight the need for new energy policies that emphasize efficiency and low-carbon energy intensity. We assessed the relationships among electricity use, coal consumption, and health outcomes. Using time-series data sets from 41 countries with varying development trajectories between 1965 and 2005, we developed an autoregressive model of life expectancy (LE) and infant mortality (IM) based on electricity consumption, coal consumption, and previous year's LE or IM. Prediction of health impacts from the Greenhouse Gas and Air Pollution Interactions and Synergies (GAINS) integrated air pollution emissions health impact model for coal-fired power plants was compared with the time-series model results. The time-series model predicted that increased electricity consumption was associated with reduced IM for countries that started with relatively high IM (> 100/1,000 live births) and low LE (electricity consumption regardless of IM and LE in 1965. Increasing coal consumption was associated with increased IM and reduced LE after accounting for electricity consumption. These results are consistent with results based on the GAINS model and previously published estimates of disease burdens attributable to energy-related environmental factors, including indoor and outdoor air pollution and water and sanitation. Increased electricity consumption in countries with IM consumption has significant detrimental health impacts.

  12. Controllable circuit

    DEFF Research Database (Denmark)

    2010-01-01

    A switch-mode power circuit comprises a controllable element and a control unit. The controllable element is configured to control a current in response to a control signal supplied to the controllable element. The control unit is connected to the controllable element and provides the control...

  13. Circuit Training.

    Science.gov (United States)

    Nelson, Jane B.

    1998-01-01

    Describes a research-based activity for high school physics students in which they build an LC circuit and find its resonant frequency of oscillation using an oscilloscope. Includes a diagram of the apparatus and an explanation of the procedures. (DDR)

  14. Electric generation situation through hybrid systems in Para state and perspectives in face of the global supply of electric power; Situacao da geracao eletrica atraves de sistemas hibridos no estado do Para e perspectivas frente a universalizacao da energia eletrica

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, Claudomiro Fabio de Oliveira; Pinho, Joao Tavares; Pereira, Edinaldo Jose da Silva; Galhardo, Marcos Andre Barros; Vale, Silvio Bispo do; Maranhao, Wilson Monteiro de Albuquerque [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Grupo de Estudos e Desenvolvimento de Alternativas Energeticas], e-mail: gedae@ufpa.br

    2004-07-01

    This work presents an analysis of the hybrid systems for electricity generation installed in the State of Para, emphasizing the profile of the supplied localities, the conversion technologies in the several configurations used for electric power generation, the social, economic and environmental impacts caused by such systems, the management and sustainability of the systems, and their perspectives in face of the global supply of electric power in Brazil. (author)

  15. Automatic recloser circuit breaker integrated with GSM technology for power system notification

    Science.gov (United States)

    Lada, M. Y.; Khiar, M. S. A.; Ghani, S. A.; Nawawi, M. R. M.; Rahim, N. H.; Sinar, L. O. M.

    2015-05-01

    Lightning is one type of transient faults that usually cause the circuit breaker in the distribution board trip due to overload current detection. The instant tripping condition in the circuit breakers clears the fault in the system. Unfortunately most circuit breakers system is manually operated. The power line will be effectively re-energized after the clearing fault process is finished. Auto-reclose circuit is used on the transmission line to carry out the duty of supplying quality electrical power to customers. In this project, an automatic reclose circuit breaker for low voltage usage is designed. The product description is the Auto Reclose Circuit Breaker (ARCB) will trip if the current sensor detects high current which exceeds the rated current for the miniature circuit breaker (MCB) used. Then the fault condition will be cleared automatically and return the power line to normal condition. The Global System for Mobile Communication (GSM) system will send SMS to the person in charge if the tripping occurs. If the over current occurs in three times, the system will fully trip (open circuit) and at the same time will send an SMS to the person in charge. In this project a 1 A is set as the rated current and any current exceeding a 1 A will cause the system to trip or interrupted. This system also provides an additional notification for user such as the emergency light and warning system.

  16. Wireless system for location of permanent faults by short circuit current monitoring in electric power distribution network; Sistema wireless para localizacao de faltas permanentes atraves da monitoracao da corrente de curto-circuito em redes de distribuicao de energia eletrica

    Energy Technology Data Exchange (ETDEWEB)

    Machado, A.G.; Correa, A.C.; Machado, R.N. das M.; Ferreira, A.M.D.; Pinto, J.A.C. [Instituto Federal de Educacao, Ciencia e Tecnologia do Para (IFPA), Belem, PA (Brazil)], E-mail: alcidesmachado000@yahoo.com.br; Barra Junior, W. [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Inst. de Tecnologia. Faculdade de Engenharia Eletrica], E-mail: walbarra@ufpa.br

    2009-07-01

    This paper presents the development of an automatic system for permanent short-circuits location in medium voltage (13.8 kV) electric power system distribution feeders, by indirect monitoring of the line current. When a permanent failure occurs, the developed system uses mobile telephony (GSM) text messages (SMS) to inform the power company operation center where the failure most likely took place. With this information in real time, the power company operation center may provide the network restoration in a faster and efficient way. (author)

  17. Investigation of Equivalent Circuit for PEMFC Assessment

    International Nuclear Information System (INIS)

    Myong, Kwang Jae

    2011-01-01

    Chemical reactions occurring in a PEMFC are dominated by the physical conditions and interface properties, and the reactions are expressed in terms of impedance. The performance of a PEMFC can be simply diagnosed by examining the impedance because impedance characteristics can be expressed by an equivalent electrical circuit. In this study, the characteristics of a PEMFC are assessed using the AC impedance and various equivalent circuits such as a simple equivalent circuit, equivalent circuit with a CPE, equivalent circuit with two RCs, and equivalent circuit with two CPEs. It was found in this study that the characteristics of a PEMFC could be assessed using impedance and an equivalent circuit, and the accuracy was highest for an equivalent circuit with two CPEs

  18. Developing a Domain Model for Relay Circuits

    DEFF Research Database (Denmark)

    Haxthausen, Anne Elisabeth

    2009-01-01

    In this paper we stepwise develop a domain model for relay circuits as used in railway control systems. First we provide an abstract, property-oriented model of networks consisting of components that can be glued together with connectors. This model is strongly inspired by a network model...... for railways madeby Bjørner et.al., however our model is more general: the components can be of any kind and can later be refined to e.g. railway components or circuit components. Then we show how the abstract network model can be refined into an explicit model for relay circuits. The circuit model describes...... the statics as well as the dynamics of relay circuits, i.e. how a relay circuit can be composed legally from electrical components as well as how the components may change state over time. Finally the circuit model is transformed into an executable model, and we show how a concrete circuit can be defined...

  19. Integrated life-cycle assessment of electricity-supply scenarios confirms global environmental benefit of low-carbon technologies.

    Science.gov (United States)

    Hertwich, Edgar G; Gibon, Thomas; Bouman, Evert A; Arvesen, Anders; Suh, Sangwon; Heath, Garvin A; Bergesen, Joseph D; Ramirez, Andrea; Vega, Mabel I; Shi, Lei

    2015-05-19

    Decarbonization of electricity generation can support climate-change mitigation and presents an opportunity to address pollution resulting from fossil-fuel combustion. Generally, renewable technologies require higher initial investments in infrastructure than fossil-based power systems. To assess the tradeoffs of increased up-front emissions and reduced operational emissions, we present, to our knowledge, the first global, integrated life-cycle assessment (LCA) of long-term, wide-scale implementation of electricity generation from renewable sources (i.e., photovoltaic and solar thermal, wind, and hydropower) and of carbon dioxide capture and storage for fossil power generation. We compare emissions causing particulate matter exposure, freshwater ecotoxicity, freshwater eutrophication, and climate change for the climate-change-mitigation (BLUE Map) and business-as-usual (Baseline) scenarios of the International Energy Agency up to 2050. We use a vintage stock model to conduct an LCA of newly installed capacity year-by-year for each region, thus accounting for changes in the energy mix used to manufacture future power plants. Under the Baseline scenario, emissions of air and water pollutants more than double whereas the low-carbon technologies introduced in the BLUE Map scenario allow a doubling of electricity supply while stabilizing or even reducing pollution. Material requirements per unit generation for low-carbon technologies can be higher than for conventional fossil generation: 11-40 times more copper for photovoltaic systems and 6-14 times more iron for wind power plants. However, only two years of current global copper and one year of iron production will suffice to build a low-carbon energy system capable of supplying the world's electricity needs in 2050.

  20. Local Design & Global Dreams - Emerging Business Models creating the Emergent Electric Vehicle Industry

    DEFF Research Database (Denmark)

    Rask, Morten; Andersen, Poul Houman; Linneberg, Mai Skjøtt

    Electric cars hold the potential to completely alter the interrelationship among actors in the automobile industry architecture. As such they may not only be able to alleviate environmental externalities but also revolutionise the automobile industry as such. This paper is concerned...... with the processes of industry creation for the electric car industry, which is a particular fascinating topic matter as it allows the analysis to provide an understanding of the processes of innovation and of some of its inventors in concert. In continuation of this, the aim of this paper is to describe and analyse...... which emergent business models and corresponding value capturing capabilities can be found in the emerging market for electric cars....

  1. Scenarios for the hierarchical evaluation of the global sustainability of electric generator plants

    International Nuclear Information System (INIS)

    Roldan A, M.C.; Martinez F, M.

    2007-01-01

    The AHP multi criteria method was applied (Analytic Hierarchy Process-Analytic process of Hierarchization) to evaluate the sustainability in the whole life cycle of the electricity generation technologies (hydroelectric, carboelectric, thermoelectric natural fuel oil, natural gas thermoelectric, geothermal, nucleo electric, wind electric, photo thermic and photovoltaic) with the purpose of offering an useful method in the taking of decisions to impel the sustainable development. Eight scenarios are analyzed. The results in most of the scenarios reflect the benefit of the renewable energy: the hydroelectric energy, photo thermic and wind driven its are those more sustainable. To reach the sustainable development in Mexico, the energy politicians should be more near to the use of the renewable energy. (Author)

  2. Electric power generated by fossil fuels: Impact and environmental administration at global and local level

    International Nuclear Information System (INIS)

    Moscarella, John Paul

    1999-01-01

    An analysis is presented on the derived environmental implications of the current and future structure in the electric power market at international level. The reduced prices of the hydrocarbons determine that the fossil electricity is imposed on other generation forms, that which generates serious challenges to the companies and the governments as regards control and handling of gases emissions. By means of a comparative sample of eight electric companies of developed countries and in development, the tendencies are evaluated in the local and regional markets, as well as the environmental effects of different generating systems of electricity. The mechanism of well-known market is analyzed as activities implemented jointly (AIJ) referred to activities to be implemented jointly to combat the greenhouse gases effect. It concludes that in the short and medium term the conditions of the market will continue favoring the generation of fossil energy, reason why they should strengthen mechanisms of the climatic change control and to impel toward the long term the development of renewable and alternative energy

  3. Balanced calibration of resonant shunt circuits for piezoelectric vibration control

    DEFF Research Database (Denmark)

    Høgsberg, Jan; Krenk, Steen

    2012-01-01

    Shunting of piezoelectric transducers and suitable electric circuits constitutes an effective passive approach to resonant vibration damping of structures. Most common design concepts for resonant resistor-inductor (RL) shunt circuits rely on either maximization of the attainable modal damping...

  4. Electrical energy in France in 2008

    International Nuclear Information System (INIS)

    2008-12-01

    The figures presented on this document account for the electricity flows recorded in Metropolitan France, including Corsica. Contents: national consumption; physical exchanges with foreign countries; electrical energy balance in France in 2008; net generation; noteworthy data for the year 2008 (daily maximum values of National consumption, Hydroelectric generation and non-Hydroelectric generation, Balance of physical exchanges); electricity market: cross-border contractual exchanges, balance responsible entities (Energy amount exchanged between balance responsible entities through the block exchange notifications), balancing mechanism (Global amount of energy activated upwards and downwards); power facilities: generating facilities in France (Nuclear, Fossil fuel thermal, Hydro-electric, Wind and Other renewable energy sources), transmission lines (circuit length in operation), transmission - transformers (installed capacity in operation); main transmission facilities commissioned during the year 2008 (substations connected to the RTE network and new or refurbished circuits)

  5. Electrical and electronic principles

    CERN Document Server

    Knight, S A

    1991-01-01

    Electrical and Electronic Principles, 2, Second Edition covers the syllabus requirements of BTEC Unit U86/329, including the principles of control systems and elements of data transmission. The book first tackles series and parallel circuits, electrical networks, and capacitors and capacitance. Discussions focus on flux density, electric force, permittivity, Kirchhoff's laws, superposition theorem, arrangement of resistors, internal resistance, and powers in a circuit. The text then takes a look at capacitors in circuit, magnetism and magnetization, electromagnetic induction, and alternating v

  6. Electrical machines with Matlab

    CERN Document Server

    Gonen, Turan

    2011-01-01

    Basic ConceptsDistribution SystemImpact of Dispersed Storage and GenerationBrief Overview of Basic Electrical MachinesReal and Reactive Powers in Single-Phase AC CircuitsThree-Phase CircuitsThree-Phase SystemsUnbalanced Three-Phase LoadsMeasurement of Average Power in Three-Phase CircuitsPower Factor CorrectionMagnetic CircuitsMagnetic Field of Current-Carrying ConductorsAmpère's Magnetic Circuital LawMagnetic CircuitsMagnetic Circuit with Air GapBrief Review of FerromagnetismMagnetic Core LossesHow to Determine Flux for a Given MMFPermanent MagnetsTransformersTransformer ConstructionBrief Rev

  7. Electricity

    International Nuclear Information System (INIS)

    Tombs, F.

    1983-01-01

    The subject is discussed, with particular reference to the electricity industry in the United Kingdom, under the headings; importance and scope of the industry's work; future fuel supplies (estimated indigenous fossil fuels reserves); outlook for UK energy supplies; problems of future generating capacity and fuel mix (energy policy; construction programme; economics and pricing; contribution of nuclear power - thermal and fast reactors; problems of conversion of oil-burning to coal-burning plant). (U.K.)

  8. Global freshwater thermal emissions from steam-electric power plants with once-through cooling systems

    International Nuclear Information System (INIS)

    Raptis, Catherine E.; Pfister, Stephan

    2016-01-01

    Large quantities of heat are rejected into freshwater bodies from power plants employing once-through cooling systems, often leading to temperature increases that disturb aquatic ecosystems. The objective of this work was to produce a high resolution global picture of power-related freshwater thermal emissions and to analyse the technological, geographical and chronological patterns behind them. The Rankine cycle was systematically solved for ∼2400 generating units with once-through cooling systems, distinguishing between simple and cogenerative cycles, giving the rejected heat as a direct output. With large unit sizes, low efficiencies, and high capacity factors, nuclear power plants reject 3.7 GW heat into freshwater on average, contrasting with 480 MW rejected from coal and gas power plants. Together, nuclear and coal-fuelled power plants from the 1970s and 1980s account for almost 50% of the rejected heat worldwide, offering motivation for their phasing out in the future. Globally, 56% of the emissions are rejected into rivers, pointing to potential areas of high thermal pollution, with the rest entering lakes and reservoirs. The outcome of this work can be used to further investigate the identified thermal emission hotspots, and to calculate regionalized water temperature increase and related impacts in environmental, energy-water nexus studies and beyond. - Highlights: • The thermodynamic cycles of ∼2400 power units with once-through cooling were solved. • Global freshwater heat emissions depend on technology, geography & chronology. • Half the global emissions come from nuclear and coal plants from the 70s & 80s. • Hotspots of freshwater thermal emissions were identified globally. • Global georeferenced emissions are available for use in water temperature models.

  9. The Local Structure of Globalization. The Network Dynamics of Foreign Direct Investments in the International Electricity Industry

    Science.gov (United States)

    Koskinen, Johan; Lomi, Alessandro

    2013-05-01

    We study the evolution of the network of foreign direct investment (FDI) in the international electricity industry during the period 1994-2003. We assume that the ties in the network of investment relations between countries are created and deleted in continuous time, according to a conditional Gibbs distribution. This assumption allows us to take simultaneously into account the aggregate predictions of the well-established gravity model of international trade as well as local dependencies between network ties connecting the countries in our sample. According to the modified version of the gravity model that we specify, the probability of observing an investment tie between two countries depends on the mass of the economies involved, their physical distance, and the tendency of the network to self-organize into local configurations of network ties. While the limiting distribution of the data generating process is an exponential random graph model, we do not assume the system to be in equilibrium. We find evidence of the effects of the standard gravity model of international trade on evolution of the global FDI network. However, we also provide evidence of significant dyadic and extra-dyadic dependencies between investment ties that are typically ignored in available research. We show that local dependencies between national electricity industries are sufficient for explaining global properties of the network of foreign direct investments. We also show, however, that network dependencies vary significantly over time giving rise to a time-heterogeneous localized process of network evolution.

  10. Global electricity transformation: The critical need for integrated market design and risk management research

    International Nuclear Information System (INIS)

    Hung-po Chao

    2006-01-01

    The past three decades transformed the electricity industry. The essential goals of liberalization have been to lower costs, improve reliability, and stimulate investment and innovations through establishment of competitive electricity markets, while also relying on market mechanisms to provide creative solutions to environmental and security problems. In many instances, these goals have been achieved, but the occurrence of some spectacular market failures have brought into question the whole restructuring effort. This paper reviews recent experiences with market reform and concludes that a significant cause of failure has been the rush to unbundle vertically integrated utilities without sufficient consideration of alternative ways to manage the risk of electricity market restructuring. In particular, there is a critical need for integrated market design and risk management research to improve the process of market transformation by taking a more evolutionary approach to discover a 'Third Way' above vertical integration and full unbundling. Such research can offer a crucial feedback link to the restructuring process by identifying important lessons to be learned from past experience and developing new analytical tools to help introduce more successful market designs for the future. (author)

  11. Global environmental problems in the electric industry. Denki jigyo ni okeru chikyu kankyo mondai ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Sugi, T [Tokyo Electric Power Co., Inc. (Japan)

    1992-09-30

    Since the electric industry has grappled with a prevention of the environmental pollution such as the air pollution and water contamination as a forerunner in case of construction and operation of the power facilities, and at the same time has conducted actively the environmental conservation countermeasures, it has consequently achieved the environmental conservation level as a top level in the world. On the other hand, as for the emission quantity of CO2 relating to the earth warming, the power field occupies about one fourth of total Japan. Therefore the electric industry should aim at the electric energy supply considering the influence on the environment, such as the power supply structure to restrain CO2 emission as less as possible, higher efficiency of equipments, higher efficiency of energy utilization by using the unused energy and so forth. In addition to it, the consumer side should aim at the social structure with a recycle type such as saving resources and saving energy, and aim at changeover of life style. It is hoped to conduct the overall measure including the items mentioned above. In this report, the recent trend of earth enviromental problems, grappling with the environmental problems as a forerunner such as the prevention measure of air pollution in the thermal power plant, etc., and the correspondence to the earth warming problems are outlined. 11 refs., 9 figs., 3 tabs.

  12. Light duty vehicle transportation and global climate policy: The importance of electric drive vehicles

    International Nuclear Information System (INIS)

    Bosetti, Valentina; Longden, Thomas

    2013-01-01

    With a focus on the interaction between long-term climate targets and personal transport we review the electrification of light duty vehicles (LDVs) within a model that utilizes a learning-by-researching structure. By modeling the demand of vehicles, the use of fuels and emissions implied, the model solves for the optimum RD and D investments that decrease the cost of hybrid, plug-in hybrid and electric vehicles. A range of technology and climate policy scenarios provide long term projections of vehicle use that highlight the potential synergies between innovation in the transportation sector and the energy sector. We find that even when the capital cost of electric drive vehicles (EDVs) remains higher than that of traditional combustion engine alternatives, EDVs are likely to play a key role in the decarbonisation implied by stringent climate policy. Limited innovation in batteries results in notable increases in policy costs consistent with a two degree climate policy target. - Highlights: • Significant increase in vehicles across regions in the medium to long term future. • Climate policy costs are sensitive to a lack of electric drive vehicles (EDVs). • Achieving 450ppm with no change in battery costs has a policy cost that is 2.86 percentage points higher than the base 450ppm scenario. • Climate policy hastens the introduction of electrified vehicles, however EDVs do not become the dominant vehicle of choice before the middle of the century

  13. Globalization

    DEFF Research Database (Denmark)

    Plum, Maja

    Globalization is often referred to as external to education - a state of affair facing the modern curriculum with numerous challenges. In this paper it is examined as internal to curriculum; analysed as a problematization in a Foucaultian sense. That is, as a complex of attentions, worries, ways...... of reasoning, producing curricular variables. The analysis is made through an example of early childhood curriculum in Danish Pre-school, and the way the curricular variable of the pre-school child comes into being through globalization as a problematization, carried forth by the comparative practices of PISA...

  14. Globalization

    OpenAIRE

    F. Gerard Adams

    2008-01-01

    The rapid globalization of the world economy is causing fundamental changes in patterns of trade and finance. Some economists have argued that globalization has arrived and that the world is “flat†. While the geographic scope of markets has increased, the author argues that new patterns of trade and finance are a result of the discrepancies between “old†countries and “new†. As the differences are gradually wiped out, particularly if knowledge and technology spread worldwide, the t...

  15. Specific features of design and electric circuit of the pulse modulator of the amplification channel of second-section linear accelerator for a meson factory

    International Nuclear Information System (INIS)

    Dyukov, L.V.; Fedorov, A.F.; Terekhov, V.F.

    1977-01-01

    The circuit and design of a modulator at pulse power of 15 MW and average power of 300 kW, intended for supplying a klystron generator, are described. The modulator is designed for operating in a lengthy mode. The capacitance storage-former is made in the form of three parallel sections of artificial shaping lines in order to lower the specific loads on the elements of the shaping line and thyristors. The thyristor spark gaps are made in the form of a unified water-cooled assembly composed of 12 series TD-320 thyristors. An assessment of the modulator reliability has shown that the average time-to-fault is 800 hr. Modulator tests confirm that the choice of the circuit solution is correct. The modulator total efficiency equals to approximately 0.9

  16. Analysis of the treatment of plastic from electrical and electronic waste in the Republic of Serbia and the testing of the recycling potential of non-metallic fractions of printed circuit boards

    Directory of Open Access Journals (Sweden)

    Vučinić Aleksandra S.

    2017-01-01

    Full Text Available This paper presents the analysis of the quantity of plastic and waste printed circuit boards obtained after the mechanical treatment of electrical and electronic waste (E-waste in the Republic of Serbia, as well as the recycling of non-metallic fractions of waste printed circuit boards. The aim is to analyze the obtained recycled material and recommendation for possible application of recyclables. The data on the quantities and treatment of plastics and printed circuit boards obtained after the mechanical treatment of WEEE, were gained through questionnaires sent to the operators who treat this type of waste. The results of the questionnaire analysis showed that in 2014 the dismantling of E-waste isolated 1,870.95 t of plastic and 499.85 t of printed circuit boards. In the Republic of Serbia, E-waste recycling is performed exclusively by using mechanical methods. Mechanical methods consist of primary crushing and separation of the materials which have a utility value as secondary raw materials, from the components and materials that have hazardous properties. Respect to that, the recycling of printed circuit boards using some of the metallurgical processes with the aim of extracting copper, precious metals and non-metallic fraction is completely absent, and the circuit boards are exported as a whole. Given the number of printed circuit boards obtained by E-waste dismantling, and the fact that from an economic point of view, hydrometallurgical methods are very suitable technological solutions in the case of a smaller capacity, there is a possibility for establishing the facilities in the Republic of Serbia for the hydrometallurgical treatment that could be used for metals extraction, and non-metallic fractions, which also have their own value. Printed circuit boards granulate obtained after the mechanical pretreatment and the selective removal of metals by hydrometallurgical processes was used for the testing of the recycling potential

  17. Potential applications for nuclear energy besides electricity generation: A global perspective

    International Nuclear Information System (INIS)

    Gauthier, Jean Claude; Ballot, Bernard; Lebrun, Jean Philippe; Lecomte, Michel; Hittner, Dominique; Carre, Frank

    2007-01-01

    Energy supply is increasingly showing up as a major issue for electricity supply, transportation, settlement, and process heat industrial supply including hydrogen production. Nuclear power is part of the solution. For electricity supply, as exemplified in Finland and France, the EPR brings an immediate answer; HTR could bring another solution in some specific cases. For other supply, mostly heat, the HTR brings a solution inaccessible to conventional nuclear power plants for very high or even high temperature. As fossil fuels costs increase and efforts to avoid generation of Greenhouse gases are implemented, a market for nuclear generated process heat will be developed. Following active developments in the 80's, HTR have been put on the back burner up to 5 years ago. Light water reactors are widely dominating the nuclear production field today. However, interest in the HTR technology was renewed in the past few years. Several commercial projects are actively promoted, most of them aiming at electricity production. ANTARES is today AREVA's response to the cogeneration market. It distinguishes itself from other concepts with its indirect cycle design powering a combined cycle power plant. Several reasons support this design choice, one of the most important of which is the design flexibility to adapt readily to combined heat and power applications. From the start, AREVA made the choice of such flexibility with the belief that the HTR market is not so much in competition with LWR in the sole electricity market but in the specific added value market of cogeneration and process heat. In view of the volatility of the costs of fossil fuels, AREVA's choice brings to the large industrial heat applications the fuel cost predictability of nuclear fuel with the efficiency of a high temperature heat sources free of Greenhouse gases emissions. The ANTARES module produces 600 MWth which can be split into the required process heat, the remaining power drives an adapted prorated

  18. Potential Applications for Nuclear Energy besides Electricity Generation: AREVA Global Perspective of HTR Potential Market

    International Nuclear Information System (INIS)

    Soutworth, Finis; Gauthier, Jean-Claude; Lecomte, Michel; Carre, Franck

    2007-01-01

    Energy supply is increasingly showing up as a major issue for electricity supply, transportation, settlement, and process heat industrial supply including hydrogen production. Nuclear power is part of the solution. For electricity supply, as exemplified in Finland and France, the EPR brings an immediate answer; HTR could bring another solution in some specific cases. For other supply, mostly heat, the HTR brings a solution inaccessible to conventional nuclear power plants for very high or even high temperature. As fossil fuels costs increase and efforts to avoid generation of Greenhouse gases are implemented, a market for nuclear generated process heat will develop. Following active developments in the 80's, HTR have been put on the back burner up to 5 years ago. Light water reactors are widely dominating the nuclear production field today. However, interest in the HTR technology was renewed in the past few years. Several commercial projects are actively promoted, most of them aiming at electricity production. ANTARES is today AREVA's response to the cogeneration market. It distinguishes itself from other concepts with its indirect cycle design powering a combined cycle power plant. Several reasons support this design choice, one of the most important of which is the design flexibility to adapt readily to combined heat and power applications. From the start, AREVA made the choice of such flexibility with the belief that the HTR market is not so much in competition with LWR in the sole electricity market but in the specific added value market of cogeneration and process heat. In view of the volatility of the costs of fossil fuels, AREVA's choice brings to the large industrial heat applications the fuel cost predictability of nuclear fuel with the efficiency of a high temperature heat source free of greenhouse gases emissions. The ANTARES module produces 600 MWth which can be split into the required process heat, the remaining power drives an adapted prorated

  19. Neuroelectric Tuning of Cortical Oscillations by Apical Dendrites in Loop Circuits

    Directory of Open Access Journals (Sweden)

    David LaBerge

    2017-06-01

    Full Text Available Bundles of relatively long apical dendrites dominate the neurons that make up the thickness of the cerebral cortex. It is proposed that a major function of the apical dendrite is to produce sustained oscillations at a specific frequency that can serve as a common timing unit for the processing of information in circuits connected to that apical dendrite. Many layer 5 and 6 pyramidal neurons are connected to thalamic neurons in loop circuits. A model of the apical dendrites of these pyramidal neurons has been used to simulate the electric activity of the apical dendrite. The results of that simulation demonstrated that subthreshold electric pulses in these apical dendrites can be tuned to specific frequencies and also can be fine-tuned to narrow bandwidths of less than one Hertz (1 Hz. Synchronous pulse outputs from the circuit loops containing apical dendrites can tune subthreshold membrane oscillations of neurons they contact. When the pulse outputs are finely tuned, they function as a local “clock,” which enables the contacted neurons to synchronously communicate with each other. Thus, a shared tuning frequency can select neurons for membership in a circuit. Unlike layer 6 apical dendrites, layer 5 apical dendrites can produce burst firing in many of their neurons, which increases the amplitude of signals in the neurons they contact. This difference in amplitude of signals serves as basis of selecting a sub-circuit for specialized processing (e.g., sustained attention within the typically larger layer 6-based circuit. After examining the sustaining of oscillations in loop circuits and the processing of spikes in network circuits, we propose that cortical functioning can be globally viewed as two systems: a loop system and a network system. The loop system oscillations influence the network system’s timing and amplitude of pulse signals, both of which can select circuits that are momentarily dominant in cortical activity.

  20. 30 CFR 57.6407 - Circuit testing.

    Science.gov (United States)

    2010-07-01

    ...) Continuity of each electric detonator in the blasthole prior to stemming and connection to the blasting line... connection of electric detonator series; and (4) Total blasting circuit resistance prior to connection to the...) Continuity of blasting lines prior to the connection of electric detonators. Nonelectric Blasting—Surface and...