30 CFR 75.511 - Low-, medium-, or high-voltage distribution circuits and equipment; repair.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Low-, medium-, or high-voltage distribution... Electrical Equipment-General § 75.511 Low-, medium-, or high-voltage distribution circuits and equipment; repair. [Statutory Provision] No electrical work shall be performed on low-, medium-, or high-voltage...

Analysis Impact of Distributed Generation Injection to Profile of Voltage and Short-Circuit Fault in 20 kV Distribution Network System

NASA Astrophysics Data System (ADS)

Mulyadi, Y.; Sucita, T.; Rahmawan, M. D.

2018-01-01

This study was a case study in PT. PLN (Ltd.) APJ Bandung area with the subject taken was the installation of distributed generation (DG) on 20-kV distribution channels. The purpose of this study is to find out the effect of DG to the changes in voltage profile and three-phase short circuit fault in the 20-kV distribution system with load conditions considered to be balanced. The reason for this research is to know how far DG can improve the voltage profile of the channel and to what degree DG can increase the three-phase short circuit fault on each bus. The method used in this study was comparing the simulation results of power flow and short-circuit fault using ETAP Power System software with manual calculations. The result obtained from the power current simulation before the installation of DG voltage was the drop at the end of the channel at 2.515%. Meanwhile, the three-phase short-circuit current fault before the DG installation at the beginning of the channel was 13.43 kA. After the installation of DG with injection of 50%, DG power obtained voltage drop at the end of the channel was 1.715% and the current fault at the beginning network was 14.05 kA. In addition, with injection of 90%, DG power obtained voltage drop at the end of the channel was 1.06% and the current fault at the beginning network was 14.13%.

Beyond the temporal pole: limbic memory circuit in the semantic variant of primary progressive aphasia.

PubMed

Tan, Rachel H; Wong, Stephanie; Kril, Jillian J; Piguet, Olivier; Hornberger, Michael; Hodges, John R; Halliday, Glenda M

2014-07-01

Despite accruing evidence for relative preservation of episodic memory in the semantic variant of primary progressive aphasia (previously semantic dementia), the neural basis for this remains unclear, particularly in light of their well-established hippocampal involvement. We recently investigated the Papez network of memory structures across pathological subtypes of behavioural variant frontotemporal dementia and demonstrated severe degeneration of all relay nodes, with the anterior thalamus in particular emerging as crucial for intact episodic memory. The present study investigated the status of key components of Papez circuit (hippocampus, mammillary bodies, anterior thalamus, cingulate cortex) and anterior temporal cortex using volumetric and quantitative cell counting methods in pathologically-confirmed cases with semantic variant of primary progressive aphasia (n = 8; 61-83 years; three males), behavioural variant frontotemporal dementia with TDP pathology (n = 9; 53-82 years; six males) and healthy controls (n = 8, 50-86 years; four males). Behavioural variant frontotemporal dementia cases with TDP pathology were selected because of the association between the semantic variant of primary progressive aphasia and TDP pathology. Our findings revealed that the semantic variant of primary progressive aphasia and behavioural variant frontotemporal dementia show similar degrees of anterior thalamic atrophy. The mammillary bodies and hippocampal body and tail were preserved in the semantic variant of primary progressive aphasia but were significantly atrophic in behavioural variant frontotemporal dementia. Importantly, atrophy in the anterior thalamus and mild progressive atrophy in the body of the hippocampus emerged as the main memory circuit regions correlated with increasing dementia severity in the semantic variant of primary progressive aphasia. Quantitation of neuronal populations in the cingulate cortices confirmed the selective loss of anterior cingulate

Integrated-Circuit Pseudorandom-Number Generator

NASA Technical Reports Server (NTRS)

Steelman, James E.; Beasley, Jeff; Aragon, Michael; Ramirez, Francisco; Summers, Kenneth L.; Knoebel, Arthur

1992-01-01

Integrated circuit produces 8-bit pseudorandom numbers from specified probability distribution, at rate of 10 MHz. Use of Boolean logic, circuit implements pseudorandom-number-generating algorithm. Circuit includes eight 12-bit pseudorandom-number generators, outputs are uniformly distributed. 8-bit pseudorandom numbers satisfying specified nonuniform probability distribution are generated by processing uniformly distributed outputs of eight 12-bit pseudorandom-number generators through "pipeline" of D flip-flops, comparators, and memories implementing conditional probabilities on zeros and ones.

Cognitive Consilience: Primate Non-Primary Neuroanatomical Circuits Underlying Cognition

PubMed Central

Solari, Soren Van Hout; Stoner, Rich

2011-01-01

Interactions between the cerebral cortex, thalamus, and basal ganglia form the basis of cognitive information processing in the mammalian brain. Understanding the principles of neuroanatomical organization in these structures is critical to understanding the functions they perform and ultimately how the human brain works. We have manually distilled and synthesized hundreds of primate neuroanatomy facts into a single interactive visualization. The resulting picture represents the fundamental neuroanatomical blueprint upon which cognitive functions must be implemented. Within this framework we hypothesize and detail 7 functional circuits corresponding to psychological perspectives on the brain: consolidated long-term declarative memory, short-term declarative memory, working memory/information processing, behavioral memory selection, behavioral memory output, cognitive control, and cortical information flow regulation. Each circuit is described in terms of distinguishable neuronal groups including the cerebral isocortex (9 pyramidal neuronal groups), parahippocampal gyrus and hippocampus, thalamus (4 neuronal groups), basal ganglia (7 neuronal groups), metencephalon, basal forebrain, and other subcortical nuclei. We focus on neuroanatomy related to primate non-primary cortical systems to elucidate the basis underlying the distinct homotypical cognitive architecture. To display the breadth of this review, we introduce a novel method of integrating and presenting data in multiple independent visualizations: an interactive website (http://www.frontiersin.org/files/cognitiveconsilience/index.html) and standalone iPhone and iPad applications. With these tools we present a unique, annotated view of neuroanatomical consilience (integration of knowledge). PMID:22194717

Silicon photonic transceiver circuit for high-speed polarization-based discrete variable quantum key distribution

DOE PAGES

Cai, Hong; Long, Christopher M.; DeRose, Christopher T.; ...

2017-01-01

We demonstrate a silicon photonic transceiver circuit for high-speed discrete variable quantum key distribution that employs a common structure for transmit and receive functions. The device is intended for use in polarization-based quantum cryptographic protocols, such as BB84. Our characterization indicates that the circuit can generate the four BB84 states (TE/TM/45°/135° linear polarizations) with >30 dB polarization extinction ratios and gigabit per second modulation speed, and is capable of decoding any polarization bases differing by 90° with high extinction ratios.

Silicon photonic transceiver circuit for high-speed polarization-based discrete variable quantum key distribution.

PubMed

Cai, Hong; Long, Christopher M; DeRose, Christopher T; Boynton, Nicholas; Urayama, Junji; Camacho, Ryan; Pomerene, Andrew; Starbuck, Andrew L; Trotter, Douglas C; Davids, Paul S; Lentine, Anthony L

2017-05-29

We demonstrate a silicon photonic transceiver circuit for high-speed discrete variable quantum key distribution that employs a common structure for transmit and receive functions. The device is intended for use in polarization-based quantum cryptographic protocols, such as BB84. Our characterization indicates that the circuit can generate the four BB84 states (TE/TM/45°/135° linear polarizations) with >30 dB polarization extinction ratios and gigabit per second modulation speed, and is capable of decoding any polarization bases differing by 90° with high extinction ratios.

Silicon photonic transceiver circuit for high-speed polarization-based discrete variable quantum key distribution

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cai, Hong; Long, Christopher M.; DeRose, Christopher T.

We demonstrate a silicon photonic transceiver circuit for high-speed discrete variable quantum key distribution that employs a common structure for transmit and receive functions. The device is intended for use in polarization-based quantum cryptographic protocols, such as BB84. Our characterization indicates that the circuit can generate the four BB84 states (TE/TM/45°/135° linear polarizations) with >30 dB polarization extinction ratios and gigabit per second modulation speed, and is capable of decoding any polarization bases differing by 90° with high extinction ratios.

Multiple output power supply circuit for an ion engine with shared upper inverter

NASA Technical Reports Server (NTRS)

Cardwell, Jr., Gilbert I. (Inventor); Phelps, Thomas K. (Inventor)

2001-01-01

A power supply circuit for an ion engine suitable for a spacecraft is coupled to a bus having a bus input and a bus return. The power supply circuit has a first primary winding of a first transformer. An upper inverter circuit is coupled to the bus input and the first primary winding. The power supply circuit further includes a first lower inverter circuit coupled to the bus return and the first primary winding. The second primary winding of a second transformer is coupled to the upper inverter circuit. A second lower inverter circuit is coupled to the bus return and the second primary winding.

The modelling of carbon-based supercapacitors: Distributions of time constants and Pascal Equivalent Circuits

NASA Astrophysics Data System (ADS)

Fletcher, Stephen; Kirkpatrick, Iain; Dring, Roderick; Puttock, Robert; Thring, Rob; Howroyd, Simon

2017-03-01

Supercapacitors are an emerging technology with applications in pulse power, motive power, and energy storage. However, their carbon electrodes show a variety of non-ideal behaviours that have so far eluded explanation. These include Voltage Decay after charging, Voltage Rebound after discharging, and Dispersed Kinetics at long times. In the present work, we establish that a vertical ladder network of RC components can reproduce all these puzzling phenomena. Both software and hardware realizations of the network are described. In general, porous carbon electrodes contain random distributions of resistance R and capacitance C, with a wider spread of log R values than log C values. To understand what this implies, a simplified model is developed in which log R is treated as a Gaussian random variable while log C is treated as a constant. From this model, a new family of equivalent circuits is developed in which the continuous distribution of log R values is replaced by a discrete set of log R values drawn from a geometric series. We call these Pascal Equivalent Circuits. Their behaviour is shown to resemble closely that of real supercapacitors. The results confirm that distributions of RC time constants dominate the behaviour of real supercapacitors.

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

NASA Astrophysics Data System (ADS)

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.

Modeling the transport of nitrogen in an NPP-2006 reactor circuit

NASA Astrophysics Data System (ADS)

Stepanov, O. E.; Galkin, I. Yu.; Sledkov, R. M.; Melekh, S. S.; Strebnev, N. A.

2016-07-01

Efficient radiation protection of the public and personnel requires detecting an accident-initiating event quickly. Specifically, if a heat-exchange tube in a steam generator is ruptured, the 16N radioactive nitrogen isotope, which contributes to a sharp increase in the steam activity before the turbine, may serve as the signaling component. This isotope is produced in the core coolant and is transported along the circulation circuit. The aim of the present study was to model the transport of 16N in the primary and the secondary circuits of a VVER-1000 reactor facility (RF) under nominal operation conditions. KORSAR/GP and RELAP5/Mod.3.2 codes were used to perform the calculations. Computational models incorporating the major components of the primary and the secondary circuits of an NPP-2006 RF were constructed. These computational models were subjected to cross-verification, and the calculation results were compared to the experimental data on the distribution of the void fraction over the steam generator height. The models were proven to be valid. It was found that the time of nitrogen transport from the core to the heat-exchange tube leak was no longer than 1 s under RF operation at a power level of 100% N nom with all primary circuit pumps activated. The time of nitrogen transport from the leak to the γ-radiation detection unit under the same operating conditions was no longer than 9 s, and the nitrogen concentration in steam was no less than 1.4% (by mass) of its concentration at the reactor outlet. These values were obtained using conservative approaches to estimating the leak flow and the transport time, but the radioactive decay of nitrogen was not taken into account. Further research concerned with the calculation of thermohydraulic processes should be focused on modeling the transport of nitrogen under RF operation with some primary circuit pumps deactivated.

Development and Analysis of Cold Trap for Use in Fission Surface Power-Primary Test Circuit

NASA Technical Reports Server (NTRS)

Wolfe, T. M.; Dervan, C. A.; Pearson, J. B.; Godfroy, T. J.

2012-01-01

The design and analysis of a cold trap proposed for use in the purification of circulated eutectic sodium potassium (NaK-78) loops is presented. The cold trap is designed to be incorporated into the Fission Surface Power-Primary Test Circuit (FSP-PTC), which incorporates a pumped NaK loop to simulate in-space nuclear reactor-based technology using non-nuclear test methodology as developed by the Early Flight Fission-Test Facility. The FSP-PTC provides a test circuit for the development of fission surface power technology. This system operates at temperatures that would be similar to those found in a reactor (500-800 K). By dropping the operating temperature of a specified percentage of NaK flow through a bypass containing a forced circulation cold trap, the NaK purity level can be increased by precipitating oxides from the NaK and capturing them within the cold trap. This would prevent recirculation of these oxides back through the system, which may help prevent corrosion.

The Voltage Distribution Characteristics of a Hybrid Circuit Breaker During High Current Interruption

NASA Astrophysics Data System (ADS)

Cheng, Xian; Duan, Xiongying; Liao, Minfu; Huang, Zhihui; Luo, Yan; Zou, Jiyan

2013-08-01

Hybrid circuit breaker (HCB) technology based on a vacuum interrupter and a SF6 interrupter in series has become a new research direction because of the low-carbon requirements for high voltage switches. The vacuum interrupter has an excellent ability to deal with the steep rising part of the transient recovery voltage (TRV), while the SF6 interrupter can withstand the peak part of the voltage easily. An HCB can take advantage of the interrupters in the current interruption process. In this study, an HCB model based on the vacuum ion diffusion equations, ion density equation, and modified Cassie-Mayr arc equation is explored. A simulation platform is constructed by using a set of software called the alternative transient program (ATP). An HCB prototype is also designed, and the short circuit current is interrupted by the HCB under different action sequences of contacts. The voltage distribution of the HCB is analyzed through simulations and tests. The results demonstrate that if the vacuum interrupter withstands the initial TRV and interrupts the post-arc current first, then the recovery speed of the dielectric strength of the SF6 interrupter will be fast. The voltage distribution between two interrupters is determined by their post-arc resistance, which happens after current-zero, and subsequently, it is determined by the capacitive impedance after the post-arc current decays to zero.

Power dissipation in fractal AC circuits

NASA Astrophysics Data System (ADS)

Chen, Joe P.; Rogers, Luke G.; Anderson, Loren; Andrews, Ulysses; Brzoska, Antoni; Coffey, Aubrey; Davis, Hannah; Fisher, Lee; Hansalik, Madeline; Loew, Stephen; Teplyaev, Alexander

2017-08-01

We extend Feynman’s analysis of an infinite ladder circuit to fractal circuits, providing examples in which fractal circuits constructed with purely imaginary impedances can have characteristic impedances with positive real part. Using (weak) self-similarity of our fractal structures, we provide algorithms for studying the equilibrium distribution of energy on these circuits. This extends the analysis of self-similar resistance networks introduced by Fukushima, Kigami, Kusuoka, and more recently studied by Strichartz et al.

30 CFR 56.6402 - Deenergized circuits near detonators.

Code of Federal Regulations, 2010 CFR

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... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Deenergized circuits near detonators. 56.6402...

Pain distribution in primary care patients with hip osteoarthritis.

PubMed

Poulsen, Erik; Overgaard, Søren; Vestergaard, Jacob T; Christensen, Henrik W; Hartvigsen, Jan

2016-12-01

Hip osteoarthritis (OA) is the most common diagnosis in primary care adult patients presenting with hip pain but pain location and pain distribution in primary care patients with hip OA have been reported inadequately. To describe pain location and pain distribution in primary care patients with clinical and radiographic confirmed hip OA. Primary care patients with unilateral clinical and radiographic hip OA living on the island of Funen, Denmark were recruited from primary care to participate in a randomized clinical trial. At baseline, patients recorded pain intensity using an 11-box numeric rating scale and the distribution of hip pain using a manikin displaying three separate views: front, back and lateral. Pain drawings were analysed using a template to determine the most frequent pain locations and distribution of pain. Pain drawings were completed by 109 patients of which 108 (99%) were valid. The mean age of patients was 65 (SD 9) years and 44% were females. The mean pain intensity was 5.4 (SD 2.0). A total of 77% had marked the greater trochanter area, 53% the groin area, 42% the anterior/lateral thigh area, 38% the buttock area, 17% the knee and 15% the lower leg area. No patients marked pain exclusively in the areas of the knee, posterior thigh or lower leg. The most common pain locations of patients with hip OA presenting to primary care are the greater trochanter, groin, thigh and buttock areas. No patients recorded pain exclusively in the knee or lower leg. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Modulation of distributed feedback (DFB) laser diode with the autonomous Chua's circuit: Theory and experiment

NASA Astrophysics Data System (ADS)

Talla Mbé, Jimmi Hervé; Woafo, Paul

2018-03-01

We report on a simple way to generate complex optical waveforms with very cheap and accessible equipments. The general idea consists in modulating a laser diode with an autonomous electronic oscillator, and in the case of this study, we use a distributed feedback (DFB) laser diode pumped with an electronic Chua's circuit. Based on the adiabatic P-I characteristics of the laser diode at low frequencies, we show that when the total pump is greater than the laser threshold, it is possible to convert the electrical waveforms of the Chua's circuit into optical carriers. But, if that is not the case, the on-off dynamical behavior of the laser permits to obtain many other optical waveform signals, mainly pulses. Our numerical results are consistent with experimental measurements. The work presents the advantage of extending the range of possible chaotic dynamics of the laser diodes in the time domains (millisecond) where it is not usually expected with conventional modulation techniques. Moreover, this new technique of laser diodes modulation brings a general benefit in the physical equipment, reduces their cost and congestion so that, it can constitute a step towards photonic integrated circuits.

Cellular complexity in subcortical white matter: a distributed control circuit?

PubMed

Colombo, Jorge A

2018-03-01

The subcortical white matter (SWM) has been traditionally considered as a site for passive-neutral-information transfer through cerebral cortex association and projection fibers. Yet, the presence of subcortical neuronal and glial "interstitial" cells expressing immunolabelled neurotransmitters/neuromodulators and synaptic vesicular proteins, and recent immunohistochemical and electrophysiological observations on the rat visual cortex as well as interactive regulation of myelinating processes support the possibility that SWM nests subcortical, regionally variable, distributed neuronal-glial circuits, that could influence information transfer. Their hypothetical involvement in regulating the timing and signal transfer probability at the SWM axonal components ought to be considered and experimentally analysed. Thus, the "interstitial" neuronal cells-associated with local glial cells-traditionally considered to be vestigial and functionally inert under normal conditions, they may well turn to be critical in regulating information transfer at the SWM.

PCSIM: A Parallel Simulation Environment for Neural Circuits Fully Integrated with Python

PubMed Central

Pecevski, Dejan; Natschläger, Thomas; Schuch, Klaus

2008-01-01

The Parallel Circuit SIMulator (PCSIM) is a software package for simulation of neural circuits. It is primarily designed for distributed simulation of large scale networks of spiking point neurons. Although its computational core is written in C++, PCSIM's primary interface is implemented in the Python programming language, which is a powerful programming environment and allows the user to easily integrate the neural circuit simulator with data analysis and visualization tools to manage the full neural modeling life cycle. The main focus of this paper is to describe PCSIM's full integration into Python and the benefits thereof. In particular we will investigate how the automatically generated bidirectional interface and PCSIM's object-oriented modular framework enable the user to adopt a hybrid modeling approach: using and extending PCSIM's functionality either employing pure Python or C++ and thus combining the advantages of both worlds. Furthermore, we describe several supplementary PCSIM packages written in pure Python and tailored towards setting up and analyzing neural simulations. PMID:19543450

14 CFR 25.1357 - Circuit protective devices.

Code of Federal Regulations, 2013 CFR

2013-01-01

... designed to de-energize and disconnect faulty power sources and power transmission equipment from their... malfunctioning. (c) Each resettable circuit protective device must be designed so that, when an overload or... must be designed so that circuit breakers are not the primary means to remove or reset system power...

14 CFR 25.1357 - Circuit protective devices.

Code of Federal Regulations, 2012 CFR

2012-01-01

... designed to de-energize and disconnect faulty power sources and power transmission equipment from their... malfunctioning. (c) Each resettable circuit protective device must be designed so that, when an overload or... must be designed so that circuit breakers are not the primary means to remove or reset system power...

14 CFR 25.1357 - Circuit protective devices.

Code of Federal Regulations, 2014 CFR

2014-01-01

... designed to de-energize and disconnect faulty power sources and power transmission equipment from their... malfunctioning. (c) Each resettable circuit protective device must be designed so that, when an overload or... must be designed so that circuit breakers are not the primary means to remove or reset system power...

14 CFR 25.1357 - Circuit protective devices.

Code of Federal Regulations, 2011 CFR

2011-01-01

... designed to de-energize and disconnect faulty power sources and power transmission equipment from their... malfunctioning. (c) Each resettable circuit protective device must be designed so that, when an overload or... must be designed so that circuit breakers are not the primary means to remove or reset system power...

Experimental investigation of localized stress-induced leakage current distribution in gate dielectrics using array test circuit

NASA Astrophysics Data System (ADS)

Park, Hyeonwoo; Teramoto, Akinobu; Kuroda, Rihito; Suwa, Tomoyuki; Sugawa, Shigetoshi

2018-04-01

Localized stress-induced leakage current (SILC) has become a major problem in the reliability of flash memories. To reduce it, clarifying the SILC mechanism is important, and statistical measurement and analysis have to be carried out. In this study, we applied an array test circuit that can measure the SILC distribution of more than 80,000 nMOSFETs with various gate areas at a high speed (within 80 s) and a high accuracy (on the 10-17 A current order). The results clarified that the distributions of localized SILC in different gate areas follow a universal distribution assuming the same SILC defect density distribution per unit area, and the current of localized SILC defects does not scale down with the gate area. Moreover, the distribution of SILC defect density and its dependence on the oxide field for measurement (E OX-Measure) were experimentally determined for fabricated devices.

Eco-friendly preparation of large-sized graphene via short-circuit discharge of lithium primary battery.

PubMed

Kang, Shaohong; Yu, Tao; Liu, Tingting; Guan, Shiyou

2018-02-15

We proposed a large-sized graphene preparation method by short-circuit discharge of the lithium-graphite primary battery for the first time. LiC x is obtained through lithium ions intercalation into graphite cathode in the above primary battery. Graphene was acquired by chemical reaction between LiC x and stripper agents with dispersion under sonication conditions. The gained graphene is characterized by Raman spectrum, X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Atomic force microscope (AFM) and Scanning electron microscopy (SEM). The results indicate that the as-prepared graphene has a large size and few defects, and it is monolayer or less than three layers. The quality of graphene is significant improved compared to the reported electrochemical methods. The yield of graphene can reach 8.76% when the ratio of the H 2 O and NMP is 3:7. This method provides a potential solution for the recycling of waste lithium ion batteries. Copyright © 2017 Elsevier Inc. All rights reserved.

30 CFR 57.6402 - Deenergized circuits near detonators.

Code of Federal Regulations, 2010 CFR

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...

46 CFR 169.682 - Distribution and circuit loads.

Code of Federal Regulations, 2010 CFR

2010-10-01

... the rating of the overcurrent protective device, computed using the greater of— (1) The lamp sizes to be installed; or (2) 50 watts per outlet. (b) Circuits supplying electrical discharge lamps must be...

Single event upset protection circuit and method

DOEpatents

Wallner, John; Gorder, Michael

2016-03-22

An SEU protection circuit comprises first and second storage means for receiving primary and redundant versions, respectively, of an n-bit wide data value that is to be corrected in case of an SEU occurrence; the correction circuit requires that the data value be a 1-hot encoded value. A parity engine performs a parity operation on the n bits of the primary data value. A multiplexer receives the primary and redundant data values and the parity engine output at respective inputs, and is arranged to pass the primary data value to an output when the parity engine output indicates `odd` parity, and to pass the redundant data value to the output when the parity engine output indicates `even` parity. The primary and redundant data values are suitably state variables, and the parity engine is preferably an n-bit wide XOR or XNOR gate.

Modifications to the Fission Surface Power Primary Test Circuit (FSP-PTC)

NASA Technical Reports Server (NTRS)

Garber, Anne E.

2008-01-01

An actively pumped alkali metal flow circuit, designed and fabricated at the NASA Marshall Space Flight Center, underwent a range of tests at MSFC in early 2007. During this period, system transient responses and the performance of the liquid metal pump were evaluated. In May of 2007, the circuit was drained and cleaned to prepare for multiple modifications: the addition of larger upper and lower reservoirs, the installation of an annular linear induction pump (ALIP), and the inclusion of a closeable orifice in the test section. Modifications are now complete and testing has resumed. Performance of the ALIp, provided by Idaho National Laboratory (INL), is the subject of the first round ofexperimentation. This paper provides a summary of the tests conducted on the original circuit, details the physical changes that have since been made to it, and describes the current test program.

New equivalent lumped electrical circuit for piezoelectric transformers.

PubMed

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.

The Challenges of Distributing Leadership in Irish Post-Primary Schools

ERIC Educational Resources Information Center

O'Donovan, Margaret

2015-01-01

This study explores the challenges and opportunities in relation to developing distributed leadership practice in Irish post-primary schools. It considers school leadership within the context of contemporary distributed leadership theory. Associated concepts such as distributed cognition and activity theory are used to frame the study. The study…

Characteristic and intermingled neocortical circuits encode different visual object discriminations.

PubMed

Zhang, Guo-Rong; Zhao, Hua; Cook, Nathan; Svestka, Michael; Choi, Eui M; Jan, Mary; Cook, Robert G; Geller, Alfred I

2017-07-28

Synaptic plasticity and neural network theories hypothesize that the essential information for advanced cognitive tasks is encoded in specific circuits and neurons within distributed neocortical networks. However, these circuits are incompletely characterized, and we do not know if a specific discrimination is encoded in characteristic circuits among multiple animals. Here, we determined the spatial distribution of active neurons for a circuit that encodes some of the essential information for a cognitive task. We genetically activated protein kinase C pathways in several hundred spatially-grouped glutamatergic and GABAergic neurons in rat postrhinal cortex, a multimodal associative area that is part of a distributed circuit that encodes visual object discriminations. We previously established that this intervention enhances accuracy for specific discriminations. Moreover, the genetically-modified, local circuit in POR cortex encodes some of the essential information, and this local circuit is preferentially activated during performance, as shown by activity-dependent gene imaging. Here, we mapped the positions of the active neurons, which revealed that two image sets are encoded in characteristic and different circuits. While characteristic circuits are known to process sensory information, in sensory areas, this is the first demonstration that characteristic circuits encode specific discriminations, in a multimodal associative area. Further, the circuits encoding the two image sets are intermingled, and likely overlapping, enabling efficient encoding. Consistent with reconsolidation theories, intermingled and overlapping encoding could facilitate formation of associations between related discriminations, including visually similar discriminations or discriminations learned at the same time or place. Copyright © 2017 Elsevier B.V. All rights reserved.

Mapping sensory circuits by anterograde trans-synaptic transfer of recombinant rabies virus

PubMed Central

Zampieri, Niccolò; Jessell, Thomas M.; Murray, Andrew J.

2014-01-01

Summary Primary sensory neurons convey information from the external world to relay circuits within the central nervous system (CNS), but the identity and organization of the neurons that process incoming sensory information remains sketchy. Within the CNS viral tracing techniques that rely on retrograde trans-synaptic transfer provide a powerful tool for delineating circuit organization. Viral tracing of the circuits engaged by primary sensory neurons has, however, been hampered by the absence of a genetically tractable anterograde transfer system. In this study we demonstrate that rabies virus can infect sensory neurons in the somatosensory system, is subject to anterograde trans-synaptic transfer from primary sensory to spinal target neurons, and can delineate output connectivity with third-order neurons. Anterograde trans-synaptic transfer is a feature shared by other classes of primary sensory neurons, permitting the identification and potentially the manipulation of neural circuits processing sensory feedback within the mammalian CNS. PMID:24486087

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

NASA Astrophysics Data System (ADS)

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.

Electric Vehicle Interaction at the Electrical Circuit Level

DOT National Transportation Integrated Search

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...

Highly localized distributed Brillouin scattering response in a photonic integrated circuit

NASA Astrophysics Data System (ADS)

Zarifi, Atiyeh; Stiller, Birgit; Merklein, Moritz; Li, Neuton; Vu, Khu; Choi, Duk-Yong; Ma, Pan; Madden, Stephen J.; Eggleton, Benjamin J.

2018-03-01

The interaction of optical and acoustic waves via stimulated Brillouin scattering (SBS) has recently reached on-chip platforms, which has opened new fields of applications ranging from integrated microwave photonics and on-chip narrow-linewidth lasers, to phonon-based optical delay and signal processing schemes. Since SBS is an effect that scales exponentially with interaction length, on-chip implementation on a short length scale is challenging, requiring carefully designed waveguides with optimized opto-acoustic overlap. In this work, we use the principle of Brillouin optical correlation domain analysis to locally measure the SBS spectrum with high spatial resolution of 800 μm and perform a distributed measurement of the Brillouin spectrum along a spiral waveguide in a photonic integrated circuit. This approach gives access to local opto-acoustic properties of the waveguides, including the Brillouin frequency shift and linewidth, essential information for the further development of high quality photonic-phononic waveguides for SBS applications.

46 CFR 28.860 - Overcurrent protection and switched circuits.

Code of Federal Regulations, 2010 CFR

2010-10-01

... current carrying conductor must be protected in accordance with its current carrying capacity by a circuit breaker or fuse at the connection to the switchboard or distribution panel bus. (d) Each circuit breaker...

46 CFR 28.860 - Overcurrent protection and switched circuits.

Code of Federal Regulations, 2011 CFR

2011-10-01

... current carrying conductor must be protected in accordance with its current carrying capacity by a circuit breaker or fuse at the connection to the switchboard or distribution panel bus. (d) Each circuit breaker...

Power supply circuit for an ion engine sequentially operated power inverters

NASA Technical Reports Server (NTRS)

Cardwell, Jr., Gilbert I. (Inventor)

2000-01-01

A power supply circuit for an ion engine suitable for a spacecraft has a voltage bus having input line and a return line. The power supply circuit includes a pulse width modulation circuit. A plurality of bridge inverter circuits is coupled to the bus and the pulse width modulation circuit. The pulse width modulation circuit generates operating signals having a variable duty cycle. Each bridge inverter has a primary winding and a secondary winding. Each secondary winding is coupled to a rectifier bridge. Each secondary winding is coupled in series with another of the plurality of rectifier bridges.

The primary visual cortex in the neural circuit for visual orienting

NASA Astrophysics Data System (ADS)

Zhaoping, Li

The primary visual cortex (V1) is traditionally viewed as remote from influencing brain's motor outputs. However, V1 provides the most abundant cortical inputs directly to the sensory layers of superior colliculus (SC), a midbrain structure to command visual orienting such as shifting gaze and turning heads. I will show physiological, anatomical, and behavioral data suggesting that V1 transforms visual input into a saliency map to guide a class of visual orienting that is reflexive or involuntary. In particular, V1 receives a retinotopic map of visual features, such as orientation, color, and motion direction of local visual inputs; local interactions between V1 neurons perform a local-to-global computation to arrive at a saliency map that highlights conspicuous visual locations by higher V1 responses. The conspicuous location are usually, but not always, where visual input statistics changes. The population V1 outputs to SC, which is also retinotopic, enables SC to locate, by lateral inhibition between SC neurons, the most salient location as the saccadic target. Experimental tests of this hypothesis will be shown. Variations of the neural circuit for visual orienting across animal species, with more or less V1 involvement, will be discussed. Supported by the Gatsby Charitable Foundation.

Distributed information system architecture for Primary Health Care.

PubMed

Grammatikou, M; Stamatelopoulos, F; Maglaris, B

2000-01-01

We present a distributed architectural framework for Primary Health Care (PHC) Centres. Distribution is handled through the introduction of the Roaming Electronic Health Care Record (R-EHCR) and the use of local caching and incremental update of a global index. The proposed architecture is designed to accommodate a specific PHC workflow model. Finally, we discuss a pilot implementation in progress, which is based on CORBA and web-based user interfaces. However, the conceptual architecture is generic and open to other middleware approaches like the DHE or HL7.

The Global Circuit.

ERIC Educational Resources Information Center

Lansford, Henry

1983-01-01

Discusses the nature of and research related to a theory explaining the earth's electric budget. The theory suggests a global electric circuit completed by a positive current flowing up into thunderstorm clouds, from clouds to ionosphere, distributed around the globe, and down to earth through the lower atmosphere in fair-weather regions. (JN)

30 CFR 75.800-3 - Testing, examination and maintenance of circuit breakers; procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... High-Voltage Distribution § 75.800-3 Testing, examination and maintenance of circuit breakers; procedures. (a) Circuit breakers and their auxiliary devices protecting underground high-voltage circuits...

Implementation of Complex Biological Logic Circuits Using Spatially Distributed Multicellular Consortia

PubMed Central

Urrios, Arturo; de Nadal, Eulàlia; Solé, Ricard; Posas, Francesc

2016-01-01

Engineered synthetic biological devices have been designed to perform a variety of functions from sensing molecules and bioremediation to energy production and biomedicine. Notwithstanding, a major limitation of in vivo circuit implementation is the constraint associated to the use of standard methodologies for circuit design. Thus, future success of these devices depends on obtaining circuits with scalable complexity and reusable parts. Here we show how to build complex computational devices using multicellular consortia and space as key computational elements. This spatial modular design grants scalability since its general architecture is independent of the circuit’s complexity, minimizes wiring requirements and allows component reusability with minimal genetic engineering. The potential use of this approach is demonstrated by implementation of complex logical functions with up to six inputs, thus demonstrating the scalability and flexibility of this method. The potential implications of our results are outlined. PMID:26829588

Working Memory and Decision-Making in a Frontoparietal Circuit Model

PubMed Central

2017-01-01

Working memory (WM) and decision-making (DM) are fundamental cognitive functions involving a distributed interacting network of brain areas, with the posterior parietal cortex (PPC) and prefrontal cortex (PFC) at the core. However, the shared and distinct roles of these areas and the nature of their coordination in cognitive function remain poorly understood. Biophysically based computational models of cortical circuits have provided insights into the mechanisms supporting these functions, yet they have primarily focused on the local microcircuit level, raising questions about the principles for distributed cognitive computation in multiregional networks. To examine these issues, we developed a distributed circuit model of two reciprocally interacting modules representing PPC and PFC circuits. The circuit architecture includes hierarchical differences in local recurrent structure and implements reciprocal long-range projections. This parsimonious model captures a range of behavioral and neuronal features of frontoparietal circuits across multiple WM and DM paradigms. In the context of WM, both areas exhibit persistent activity, but, in response to intervening distractors, PPC transiently encodes distractors while PFC filters distractors and supports WM robustness. With regard to DM, the PPC module generates graded representations of accumulated evidence supporting target selection, while the PFC module generates more categorical responses related to action or choice. These findings suggest computational principles for distributed, hierarchical processing in cortex during cognitive function and provide a framework for extension to multiregional models. SIGNIFICANCE STATEMENT Working memory and decision-making are fundamental “building blocks” of cognition, and deficits in these functions are associated with neuropsychiatric disorders such as schizophrenia. These cognitive functions engage distributed networks with prefrontal cortex (PFC) and posterior parietal

Working Memory and Decision-Making in a Frontoparietal Circuit Model.

PubMed

Murray, John D; Jaramillo, Jorge; Wang, Xiao-Jing

2017-12-13

Working memory (WM) and decision-making (DM) are fundamental cognitive functions involving a distributed interacting network of brain areas, with the posterior parietal cortex (PPC) and prefrontal cortex (PFC) at the core. However, the shared and distinct roles of these areas and the nature of their coordination in cognitive function remain poorly understood. Biophysically based computational models of cortical circuits have provided insights into the mechanisms supporting these functions, yet they have primarily focused on the local microcircuit level, raising questions about the principles for distributed cognitive computation in multiregional networks. To examine these issues, we developed a distributed circuit model of two reciprocally interacting modules representing PPC and PFC circuits. The circuit architecture includes hierarchical differences in local recurrent structure and implements reciprocal long-range projections. This parsimonious model captures a range of behavioral and neuronal features of frontoparietal circuits across multiple WM and DM paradigms. In the context of WM, both areas exhibit persistent activity, but, in response to intervening distractors, PPC transiently encodes distractors while PFC filters distractors and supports WM robustness. With regard to DM, the PPC module generates graded representations of accumulated evidence supporting target selection, while the PFC module generates more categorical responses related to action or choice. These findings suggest computational principles for distributed, hierarchical processing in cortex during cognitive function and provide a framework for extension to multiregional models. SIGNIFICANCE STATEMENT Working memory and decision-making are fundamental "building blocks" of cognition, and deficits in these functions are associated with neuropsychiatric disorders such as schizophrenia. These cognitive functions engage distributed networks with prefrontal cortex (PFC) and posterior parietal

Electronic circuits and systems: A compilation. [including integrated circuits, logic circuits, varactor diode circuits, low pass filters, and optical equipment circuits

NASA Technical Reports Server (NTRS)

1975-01-01

Technological information is presented electronic circuits and systems which have potential utility outside the aerospace community. Topics discussed include circuit components such as filters, converters, and integrators, circuits designed for use with specific equipment or systems, and circuits designed primarily for use with optical equipment or displays.

30 CFR 75.802 - Protection of high-voltage circuits extending underground.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Protection of high-voltage circuits extending...-Voltage Distribution § 75.802 Protection of high-voltage circuits extending underground. (a) Except as provided in paragraph (b) of this section, high-voltage circuits extending underground and supplying...

30 CFR 75.802 - Protection of high-voltage circuits extending underground.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Protection of high-voltage circuits extending...-Voltage Distribution § 75.802 Protection of high-voltage circuits extending underground. (a) Except as provided in paragraph (b) of this section, high-voltage circuits extending underground and supplying...

30 CFR 75.802 - Protection of high-voltage circuits extending underground.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Protection of high-voltage circuits extending...-Voltage Distribution § 75.802 Protection of high-voltage circuits extending underground. (a) Except as provided in paragraph (b) of this section, high-voltage circuits extending underground and supplying...

30 CFR 75.800-4 - Testing, examination, and maintenance of circuit breakers; record.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Underground High-Voltage Distribution § 75.800-4 Testing, examination, and maintenance of circuit breakers... adjustment of all circuit breakers protecting high-voltage circuits which enter any underground area of the...

Low Insertion HVDC Circuit Breaker: Magnetically Pulsed Hybrid Breaker for HVDC Power Distribution Protection

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2012-01-09

GENI Project: General Atomics is developing a direct current (DC) circuit breaker that could protect the grid from faults 100 times faster than its alternating current (AC) counterparts. Circuit breakers are critical elements in any electrical system. At the grid level, their main function is to isolate parts of the grid where a fault has occurred—such as a downed power line or a transformer explosion—from the rest of the system. DC circuit breakers must interrupt the system during a fault much faster than AC circuit breakers to prevent possible damage to cables, converters and other grid-level components. General Atomics’ high-voltagemore » DC circuit breaker would react in less than 1/1,000th of a second to interrupt current during a fault, preventing potential hazards to people and equipment.« less

Input clustering in the normal and learned circuits of adult barn owls.

PubMed

McBride, Thomas J; DeBello, William M

2015-05-01

Experience-dependent formation of synaptic input clusters can occur in juvenile brains. Whether this also occurs in adults is largely unknown. We previously reconstructed the normal and learned circuits of prism-adapted barn owls and found that changes in clustering of axo-dendritic contacts (putative synapses) predicted functional circuit strength. Here we asked whether comparable changes occurred in normal and prism-removed adults. Across all anatomical zones, no systematic differences in the primary metrics for within-branch or between-branch clustering were observed: 95-99% of contacts resided within clusters (<10-20 μm from nearest neighbor) regardless of circuit strength. Bouton volumes, a proxy measure of synaptic strength, were on average larger in the functionally strong zones, indicating that changes in synaptic efficacy contributed to the differences in circuit strength. Bootstrap analysis showed that the distribution of inter-contact distances strongly deviated from random not in the functionally strong zones but in those that had been strong during the sensitive period (60-250 d), indicating that clusters formed early in life were preserved regardless of current value. While cluster formation in juveniles appeared to require the production of new synapses, cluster formation in adults did not. In total, these results support a model in which high cluster dynamics in juveniles sculpt a potential connectivity map that is refined in adulthood. We propose that preservation of clusters in functionally weak adult circuits provides a storage mechanism for disused but potentially useful pathways. Copyright © 2015 Elsevier Inc. All rights reserved.

Preparation of Power Distribution System for High Penetration of Renewable Energy Part I. Dynamic Voltage Restorer for Voltage Regulation Pat II. Distribution Circuit Modeling and Validation

NASA Astrophysics Data System (ADS)

Khoshkbar Sadigh, Arash

by simulation and experimental tests under various conditions considering all possible cases such as different amounts of voltage sag depth (VSD), different amounts of point-on-wave (POW) at which voltage sag occurs, harmonic distortion, line frequency variation, and phase jump (PJ). Furthermore, the ripple amount of fundamental voltage amplitude calculated by the proposed method and its error is analyzed considering the line frequency variation together with harmonic distortion. The best and worst detection time of proposed method were measured 1ms and 8.8ms, respectively. Finally, the proposed method has been compared with other voltage sag detection methods available in literature. Part 2: Power System Modeling for Renewable Energy Integration: As power distribution systems are evolving into more complex networks, electrical engineers have to rely on software tools to perform circuit analysis. There are dozens of powerful software tools available in the market to perform the power system studies. Although their main functions are similar, there are differences in features and formatting structures to suit specific applications. This creates challenges for transferring power system circuit models data (PSCMD) between different software and rebuilding the same circuit in the second software environment. The objective of this part of thesis is to develop a Unified Platform (UP) to facilitate transferring PSCMD among different software packages and relieve the challenges of the circuit model conversion process. UP uses a commonly available spreadsheet file with a defined format, for any home software to write data to and for any destination software to read data from, via a script-based application called PSCMD transfer application. The main considerations in developing the UP are to minimize manual intervention and import a one-line diagram into the destination software or export it from the source software, with all details to allow load flow, short circuit and

CIRCUS--A digital computer program for transient analysis of electronic circuits

NASA Technical Reports Server (NTRS)

Moore, W. T.; Steinbert, L. L.

1968-01-01

Computer program simulates the time domain response of an electronic circuit to an arbitrary forcing function. CIRCUS uses a charge-control parameter model to represent each semiconductor device. Given the primary photocurrent, the transient behavior of a circuit in a radiation environment is determined.

Unbiased simulation of near-Clifford quantum circuits

DOE PAGES

Bennink, Ryan S.; Ferragut, Erik M.; Humble, Travis S.; ...

2017-06-28

Modeling and simulation are essential for predicting and verifying the behavior of fabricated quantum circuits, but existing simulation methods are either impractically costly or require an unrealistic simplification of error processes. In this paper, we present a method of simulating noisy Clifford circuits that is both accurate and practical in experimentally relevant regimes. In particular, the cost is weakly exponential in the size and the degree of non-Cliffordness of the circuit. Our approach is based on the construction of exact representations of quantum channels as quasiprobability distributions over stabilizer operations, which are then sampled, simulated, and weighted to yield unbiasedmore » statistical estimates of circuit outputs and other observables. As a demonstration of these techniques, we simulate a Steane [[7,1,3

Computer modeling of batteries from nonlinear circuit elements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Waaben, S.; Dyer, C.K.; Federico, J.

1985-06-01

Circuit analogs for a single battery cell have previously been composed of resistors, capacitors, and inductors. This work introduces a nonlinear circuit model for cell behavior. The circuit is configured around the PIN junction diode, whose charge-storage behavior has features similar to those of electrochemical cells. A user-friendly integrated circuit simulation computer program has reproduced a variety of complex cell responses including electrica isolation effects causing capacity loss, as well as potentiodynamic peaks and discharge phenomena hitherto thought to be thermodynamic in origin. However, in this work, they are shown to be simply due to spatial distribution of stored chargemore » within a practical electrode.« less

Test results management and distributed cognition in electronic health record-enabled primary care.

PubMed

Smith, Michael W; Hughes, Ashley M; Brown, Charnetta; Russo And, Elise; Giardina, Traber D; Mehta, Praveen; Singh, Hardeep

2018-06-01

Managing abnormal test results in primary care involves coordination across various settings. This study identifies how primary care teams manage test results in a large, computerized healthcare system in order to inform health information technology requirements for test results management and other distributed healthcare services. At five US Veterans Health Administration facilities, we interviewed 37 primary care team members, including 16 primary care providers, 12 registered nurses, and 9 licensed practical nurses. We performed content analysis using a distributed cognition approach, identifying patterns of information transmission across people and artifacts (e.g. electronic health records). Results illustrate challenges (e.g. information overload) as well as strategies used to overcome challenges. Various communication paths were used. Some team members served as intermediaries, processing information before relaying it. Artifacts were used as memory aids. Health information technology should address the risks of distributed work by supporting awareness of team and task status for reliable management of results.

Analysis of a Distributed Pulse Power System Using a Circuit Analysis Code

DTIC Science & Technology

1979-06-01

dose rate was then integrated to give a number that could be compared with measure- ments made using thermal luminescent dosimeters ( TLD ’ s). Since...NM 8 7117 AND THE BDM CORPORATION, ALBUQUERQUE, NM 87106 Abstract A sophisticated computer code (SCEPTRE), used to analyze electronic circuits...computer code (SCEPTRE), used to analyze electronic circuits, was used to evaluate the performance of a large flash X-ray machine. This device was

Applying analog integrated circuits for HERO protection

NASA Technical Reports Server (NTRS)

Willis, Kenneth E.; Blachowski, Thomas J.

1994-01-01

One of the most efficient methods for protecting electro-explosive devices (EED's) from HERO and ESD is to shield the EED in a conducting shell (Faraday cage). Electrical energy is transferred to the bridge by means of a magnetic coupling which passes through a portion of the conducting shell that is made from a magnetically permeable but electrically conducting material. This technique was perfected by ML Aviation, a U.K. company, in the early 80's, and was called a Radio Frequency Attenuation Connector (RFAC). It is now in wide use in the U.K. Previously, the disadvantage of RFAC over more conventional methods was its relatively high cost, largely driven by a thick film hybrid circuit used to switch the primary of the transformer. Recently, through a licensing agreement, this technology has been transferred to the U.S. and significant cost reductions and performance improvements have been achieved by the introduction of analog integrated circuits. An integrated circuit performs the following functions: (1) Chops the DC input to a signal suitable for driving the primary of the transformer; (2) Verifies the input voltage is above a threshold; (3) Verifies the input voltage is valid for a pre set time before enabling the device; (4) Provides thermal protection of the circuit; and (5) Provides an external input for independent logic level enabling of the power transfer mechanism. This paper describes the new RFAC product and its applications.

30 CFR 77.803-1 - Fail safe ground check circuits; maximum voltage.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fail safe ground check circuits; maximum... OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.803-1 Fail safe ground check circuits; maximum voltage. The maximum voltage used for ground check circuits under § 77.803 shall not...

30 CFR 77.803-1 - Fail safe ground check circuits; maximum voltage.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Fail safe ground check circuits; maximum... OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.803-1 Fail safe ground check circuits; maximum voltage. The maximum voltage used for ground check circuits under § 77.803 shall not...

Impact of physician distribution policies on primary care practices in rural Quebec.

PubMed

Da Silva, Roxane Borgès; Pineault, Raynald

2012-01-01

Accessibility and continuity of primary health care in rural Canada are inadequate, mainly because of a relative shortage of family physicians. To alleviate the uneven distribution of physicians in rural and urban regions, Quebec has implemented measures associated with 3 types of physician practices in rural areas. The objectives of our study were to describe the practices of these types of physicians in a rural area and to analyze the impact of physician distribution policies aimed at offsetting the lack of resources. Data were drawn from a medical administrative database and included information related to physicians' practices in the rural area of Beauce, Que., in 2007. The practices of permanently settled physicians in rural areas differ from those of physicians who substitute for short periods. Permanently settled physicians offer mostly primary care services, whereas physicians who temporarily substitute devote much of their time to hospital-based practice. Physician distribution policies implemented in Quebec to compensate for the lack of medical resources in rural areas have reduced the deficit in hospital care but not in primary care.

Commutation circuit for an HVDC circuit breaker

DOEpatents

Premerlani, William J.

1981-01-01

A commutation circuit for a high voltage DC circuit breaker incorporates a resistor capacitor combination and a charging circuit connected to the main breaker, such that a commutating capacitor is discharged in opposition to the load current to force the current in an arc after breaker opening to zero to facilitate arc interruption. In a particular embodiment, a normally open commutating circuit is connected across the contacts of a main DC circuit breaker to absorb the inductive system energy trapped by breaker opening and to limit recovery voltages to a level tolerable by the commutating circuit components.

Commutation circuit for an HVDC circuit breaker

DOEpatents

Premerlani, W.J.

1981-11-10

A commutation circuit for a high voltage DC circuit breaker incorporates a resistor capacitor combination and a charging circuit connected to the main breaker, such that a commutating capacitor is discharged in opposition to the load current to force the current in an arc after breaker opening to zero to facilitate arc interruption. In a particular embodiment, a normally open commutating circuit is connected across the contacts of a main DC circuit breaker to absorb the inductive system energy trapped by breaker opening and to limit recovery voltages to a level tolerable by the commutating circuit components. 13 figs.

Entanglement distribution schemes employing coherent photon-to-spin conversion in semiconductor quantum dot circuits

NASA Astrophysics Data System (ADS)

Gaudreau, Louis; Bogan, Alex; Korkusinski, Marek; Studenikin, Sergei; Austing, D. Guy; Sachrajda, Andrew S.

2017-09-01

Long distance entanglement distribution is an important problem for quantum information technologies to solve. Current optical schemes are known to have fundamental limitations. A coherent photon-to-spin interface built with quantum dots (QDs) in a direct bandgap semiconductor can provide a solution for efficient entanglement distribution. QD circuits offer integrated spin processing for full Bell state measurement (BSM) analysis and spin quantum memory. Crucially the photo-generated spins can be heralded by non-destructive charge detection techniques. We review current schemes to transfer a polarization-encoded state or a time-bin-encoded state of a photon to the state of a spin in a QD. The spin may be that of an electron or that of a hole. We describe adaptations of the original schemes to employ heavy holes which have a number of attractive properties including a g-factor that is tunable to zero for QDs in an appropriately oriented external magnetic field. We also introduce simple throughput scaling models to demonstrate the potential performance advantage of full BSM capability in a QD scheme, even when the quantum memory is imperfect, over optical schemes relying on linear optical elements and ensemble quantum memories.

Distribution of androgen receptor mRNA expression in vocal, auditory, and neuroendocrine circuits in a teleost fish.

PubMed

Forlano, Paul M; Marchaterre, Margaret; Deitcher, David L; Bass, Andrew H

2010-02-15

Across all major vertebrate groups, androgen receptors (ARs) have been identified in neural circuits that shape reproductive-related behaviors, including vocalization. The vocal control network of teleost fishes presents an archetypal example of how a vertebrate nervous system produces social, context-dependent sounds. We cloned a partial cDNA of AR that was used to generate specific probes to localize AR expression throughout the central nervous system of the vocal plainfin midshipman fish (Porichthys notatus). In the forebrain, AR mRNA is abundant in proposed homologs of the mammalian striatum and amygdala, and in anterior and posterior parvocellular and magnocellular nuclei of the preoptic area, nucleus preglomerulosus, and posterior, ventral and anterior tuberal nuclei of the hypothalamus. Many of these nuclei are part of the known vocal and auditory circuitry in midshipman. The midbrain periaqueductal gray, an essential link between forebrain and hindbrain vocal circuitry, and the lateral line recipient nucleus medialis in the rostral hindbrain also express abundant AR mRNA. In the caudal hindbrain-spinal vocal circuit, high AR mRNA is found in the vocal prepacemaker nucleus and along the dorsal periphery of the vocal motor nucleus congruent with the known pattern of expression of aromatase-containing glial cells. Additionally, abundant AR mRNA expression is shown for the first time in the inner ear of a vertebrate. The distribution of AR mRNA strongly supports the role of androgens as modulators of behaviorally defined vocal, auditory, and neuroendocrine circuits in teleost fish and vertebrates in general. 2009 Wiley-Liss, Inc.

30 CFR 75.809 - Identification of circuit breakers and disconnecting switches.

Code of Federal Regulations, 2012 CFR

2012-07-01

... disconnecting switches. 75.809 Section 75.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... High-Voltage Distribution § 75.809 Identification of circuit breakers and disconnecting switches. [Statutory Provisions] Circuit breakers and disconnecting switches underground shall be marked for...

30 CFR 75.809 - Identification of circuit breakers and disconnecting switches.

Code of Federal Regulations, 2010 CFR

2010-07-01

... disconnecting switches. 75.809 Section 75.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... High-Voltage Distribution § 75.809 Identification of circuit breakers and disconnecting switches. [Statutory Provisions] Circuit breakers and disconnecting switches underground shall be marked for...

30 CFR 75.809 - Identification of circuit breakers and disconnecting switches.

Code of Federal Regulations, 2011 CFR

2011-07-01

... disconnecting switches. 75.809 Section 75.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... High-Voltage Distribution § 75.809 Identification of circuit breakers and disconnecting switches. [Statutory Provisions] Circuit breakers and disconnecting switches underground shall be marked for...

30 CFR 75.809 - Identification of circuit breakers and disconnecting switches.

Code of Federal Regulations, 2013 CFR

2013-07-01

... disconnecting switches. 75.809 Section 75.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... High-Voltage Distribution § 75.809 Identification of circuit breakers and disconnecting switches. [Statutory Provisions] Circuit breakers and disconnecting switches underground shall be marked for...

30 CFR 75.809 - Identification of circuit breakers and disconnecting switches.

Code of Federal Regulations, 2014 CFR

2014-07-01

... disconnecting switches. 75.809 Section 75.809 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... High-Voltage Distribution § 75.809 Identification of circuit breakers and disconnecting switches. [Statutory Provisions] Circuit breakers and disconnecting switches underground shall be marked for...

30 CFR 75.800 - High-voltage circuits; circuit breakers.

Code of Federal Regulations, 2010 CFR

2010-07-01

... shall be equipped with devices to provide protection against under-voltage grounded phase, short circuit... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-voltage circuits; circuit breakers. 75.800... § 75.800 High-voltage circuits; circuit breakers. [Statutory Provisions] High-voltage circuits entering...

Size distributions of secondary and primary aerosols in Asia: A 3-D modeling

NASA Astrophysics Data System (ADS)

Yu, F.; Luo, G.; Wang, Z.

2009-12-01

Asian aerosols have received increasing attention because of their potential health and climate effects and the rapid increasing of Asian emissions associated with accelerating economic expansion. Aerosol particles appear in the atmosphere due to either in-situ nucleation (i.e, secondary particles) or direct emissions (i.e., primary particles), and their environmental impacts depend strongly on their concentrations, sizes, compositions, and mixing states. A size-resolved (sectional) particle microphysics model with a number of computationally efficient schemes has been incorporated into a global chemistry transport model (GEOS-Chem) to simulate the number size distributions of secondary and primary particles in the troposphere (Yu and Luo, Atmos. Chem. Phys. Discuss., 9, 10597-10645, 2009). The growth of nucleated particles through the condensation of sulfuric acid vapor and equilibrium uptake of nitrate, ammonium, and secondary organic aerosol is explicitly simulated, along with the coating of primary particles (dust, black carbon, organic carbon, and sea salt) by volatile components via condensation and coagulation with secondary particles. Here we look into the spatiotemporal variations of the size distributions of secondary and primary aerosols in Asia. The annual mean number concentration of the accumulation mode particles (dry diameter > ~ 100 nm) in the lower troposphere over Asia (especially China) is very high and is dominated (~70-90%) by carbonaceous primary particles (with coated condensable species). Coagulation and condensation turn the primary particles into mixed particles and on average increase the dry sizes of primary particles by a factor of ~ 2-2.5. Despite of high condensation sink, sulfuric acid vapor concentration in many parts of Asian low troposphere is very high (annual mean values above 1E7/cm3) and significant new particle formation still occurs. Secondary particles generally dominate the particles small than 100 nm and the equilibrium

Error Mitigation for Short-Depth Quantum Circuits

NASA Astrophysics Data System (ADS)

Temme, Kristan; Bravyi, Sergey; Gambetta, Jay M.

2017-11-01

Two schemes are presented that mitigate the effect of errors and decoherence in short-depth quantum circuits. The size of the circuits for which these techniques can be applied is limited by the rate at which the errors in the computation are introduced. Near-term applications of early quantum devices, such as quantum simulations, rely on accurate estimates of expectation values to become relevant. Decoherence and gate errors lead to wrong estimates of the expectation values of observables used to evaluate the noisy circuit. The two schemes we discuss are deliberately simple and do not require additional qubit resources, so to be as practically relevant in current experiments as possible. The first method, extrapolation to the zero noise limit, subsequently cancels powers of the noise perturbations by an application of Richardson's deferred approach to the limit. The second method cancels errors by resampling randomized circuits according to a quasiprobability distribution.

Measuring circuit

DOEpatents

Sun, Shan C.; Chaprnka, Anthony G.

1977-01-11

An automatic gain control circuit functions to adjust the magnitude of an input signal supplied to a measuring circuit to a level within the dynamic range of the measuring circuit while a log-ratio circuit adjusts the magnitude of the output signal from the measuring circuit to the level of the input signal and optimizes the signal-to-noise ratio performance of the measuring circuit.

30 CFR 75.803 - Fail safe ground check circuits on high-voltage resistance grounded systems.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fail safe ground check circuits on high-voltage... High-Voltage Distribution § 75.803 Fail safe ground check circuits on high-voltage resistance grounded... shall include a fail safe ground check circuit to monitor continuously the grounding circuit to assure...

30 CFR 75.803 - Fail safe ground check circuits on high-voltage resistance grounded systems.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Fail safe ground check circuits on high-voltage... High-Voltage Distribution § 75.803 Fail safe ground check circuits on high-voltage resistance grounded... shall include a fail safe ground check circuit to monitor continuously the grounding circuit to assure...

30 CFR 75.803 - Fail safe ground check circuits on high-voltage resistance grounded systems.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Fail safe ground check circuits on high-voltage... High-Voltage Distribution § 75.803 Fail safe ground check circuits on high-voltage resistance grounded... shall include a fail safe ground check circuit to monitor continuously the grounding circuit to assure...

30 CFR 75.803 - Fail safe ground check circuits on high-voltage resistance grounded systems.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Fail safe ground check circuits on high-voltage... High-Voltage Distribution § 75.803 Fail safe ground check circuits on high-voltage resistance grounded... shall include a fail safe ground check circuit to monitor continuously the grounding circuit to assure...

Distribution of essential medicines to primary care institutions in Hubei of China: effects of centralized procurement arrangements.

PubMed

Yang, Lianping; Huang, Cunrui; Liu, Chaojie

2017-11-14

Poor distribution of essential medicines to primary care institutions has attracted criticism since China adopted provincial centralized regional tendering and procurement systems. This study evaluated the impact of new procurement arrangements that limit the number of distributors at the county level in Hubei province, China. Procurement ordering and distribution data were collected from four counties that pioneered a new distribution arrangement (commencing September 2012) compared with six counties that continued the existing arrangement over the period from August 2011 to September 2013. The new arrangement allowed primary care institutions and/or suppliers to select a local distributor from a limited panel (from 3 to 5) of government nominated distributors. Difference-in-differences analyses were performed to assess the impact of the new arrangements on delivery and receipt of essential medicines. Overall, the new distribution arrangement has not improved distribution of essential medicines to primary care institutions. On the contrary, we found a 7.78-19.85 percentage point (p < 0.01) decrease in distribution rates to rural primary care institutions. Similar results were demonstrated using the indicator of received rates, with a 7.89-19.65 percentage point (p < 0.01) decrease. Simply limiting the number of distributors does not offer a solution to the poor performance of delivery of essential medicines for primary care institutions, especially those located in rural areas. Procurement arrangements need to consider the special characteristics of rural facilities. In a county, there are more rural primary care institutions than urban ones. On average, rural primary care institutions demand more and are more geographically dispersed compared to their urban counterparts, which may impose increased distribution costs.

Project Circuits in a Basic Electric Circuits Course

ERIC Educational Resources Information Center

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…

Electronic circuits

NASA Technical Reports Server (NTRS)

1976-01-01

Twenty-nine circuits and circuit techniques developed for communications and instrumentation technology are described. Topics include pulse-code modulation, phase-locked loops, data coding, data recording, detection circuits, logic circuits, oscillators, and amplifiers.

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

PubMed

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.

CHEETAH: circuit-switched high-speed end-to-end transport architecture

NASA Astrophysics Data System (ADS)

Veeraraghavan, Malathi; Zheng, Xuan; Lee, Hyuk; Gardner, M.; Feng, Wuchun

2003-10-01

Leveraging the dominance of Ethernet in LANs and SONET/SDH in MANs and WANs, we propose a service called CHEETAH (Circuit-switched High-speed End-to-End Transport ArcHitecture). The service concept is to provide end hosts with high-speed, end-to-end circuit connectivity on a call-by-call shared basis, where a "circuit" consists of Ethernet segments at the ends that are mapped into Ethernet-over-SONET long-distance circuits. This paper focuses on the file-transfer application for such circuits. For this application, the CHEETAH service is proposed as an add-on to the primary Internet access service already in place for enterprise hosts. This allows an end host that is sending a file to first attempt setting up an end-to-end Ethernet/EoS circuit, and if rejected, fall back to the TCP/IP path. If the circuit setup is successful, the end host will enjoy a much shorter file-transfer delay than on the TCP/IP path. To determine the conditions under which an end host with access to the CHEETAH service should attempt circuit setup, we analyze mean file-transfer delays as a function of call blocking probability in the circuit-switched network, probability of packet loss in the IP network, round-trip times, link rates, and so on.

Preliminary investigation on the effects of primary airflow to coal particle distribution in coal-fired boilers

NASA Astrophysics Data System (ADS)

Noor, N. A. W. Mohd; Hassan, H.; Hashim, M. F.; Hasini, H.; Munisamy, K. M.

2017-04-01

This paper presents an investigation on the effects of primary airflow to coal fineness in coal-fired boilers. In coal fired power plant, coal is pulverized in a pulverizer, and it is then transferred to boiler for combustion. Coal need to be ground to its desired size to obtain maximum combustion efficiency. Coarse coal particle size may lead to many performance problems such as formation of clinker. In this study, the effects of primary airflow to coal particles size and coal flow distribution were investigated by using isokinetic coal sampling and computational fluid dynamic (CFD) modelling. Four different primary airflows were tested and the effects to resulting coal fineness were recorded. Results show that the optimum coal fineness distribution is obtained at design primary airflow. Any reduction or increase of air flow rate results in undesirable coal fineness distribution.

Circuit-Host Coupling Induces Multifaceted Behavioral Modulations of a Gene Switch.

PubMed

Blanchard, Andrew E; Liao, Chen; Lu, Ting

2018-02-06

Quantitative modeling of gene circuits is fundamentally important to synthetic biology, as it offers the potential to transform circuit engineering from trial-and-error construction to rational design and, hence, facilitates the advance of the field. Currently, typical models regard gene circuits as isolated entities and focus only on the biochemical processes within the circuits. However, such a standard paradigm is getting challenged by increasing experimental evidence suggesting that circuits and their host are intimately connected, and their interactions can potentially impact circuit behaviors. Here we systematically examined the roles of circuit-host coupling in shaping circuit dynamics by using a self-activating gene switch as a model circuit. Through a combination of deterministic modeling, stochastic simulation, and Fokker-Planck equation formalism, we found that circuit-host coupling alters switch behaviors across multiple scales. At the single-cell level, it slows the switch dynamics in the high protein production regime and enlarges the difference between stable steady-state values. At the population level, it favors cells with low protein production through differential growth amplification. Together, the two-level coupling effects induce both quantitative and qualitative modulations of the switch, with the primary component of the effects determined by the circuit's architectural parameters. This study illustrates the complexity and importance of circuit-host coupling in modulating circuit behaviors, demonstrating the need for a new paradigm-integrated modeling of the circuit-host system-for quantitative understanding of engineered gene networks. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Compensated gain control circuit for buck regulator command charge circuit

DOEpatents

Barrett, David M.

1996-01-01

A buck regulator command charge circuit includes a compensated-gain control signal for compensating for changes in the component values in order to achieve optimal voltage regulation. The compensated-gain control circuit includes an automatic-gain control circuit for generating a variable-gain control signal. The automatic-gain control circuit is formed of a precision rectifier circuit, a filter network, an error amplifier, and an integrator circuit.

The NATO III 5 MHz Distribution System

NASA Technical Reports Server (NTRS)

Vulcan, A.; Bloch, M.

1981-01-01

A high performance 5 MHz distribution system is described which has extremely low phase noise and jitter characteristics and provides multiple buffered outputs. The system is completely redundant with automatic switchover and is self-testing. Since the 5 MHz reference signals distributed by the NATO III distribution system are used for up-conversion and multiplicative functions, a high degree of phase stability and isolation between outputs is necessary. Unique circuit design and packaging concepts insure that the isolation between outputs is sufficient to quarantee a phase perturbation of less than 0.0016 deg when other outputs are open circuited, short circuited or terminated in 50 ohms. Circuit design techniques include high isolation cascode amplifiers. Negative feedback stabilizes system gain and minimizes circuit phase noise contributions. Balanced lines, in lieu of single ended coaxial transmission media, minimize pickup.

Circuit for Communication Over Power Lines

NASA Technical Reports Server (NTRS)

Krasowski, Michael J.; Prokop, Normal F.; Greer, Lawrence C., III; Nappier, Jennifer

2011-01-01

Many distributed systems share common sensors and instruments along with a common power line supplying current to the system. A communication technique and circuit has been developed that allows for the simple inclusion of an instrument, sensor, or actuator node within any system containing a common power bus. Wherever power is available, a node can be added, which can then draw power for itself, its associated sensors, and actuators from the power bus all while communicating with other nodes on the power bus. The technique modulates a DC power bus through capacitive coupling using on-off keying (OOK), and receives and demodulates the signal from the DC power bus through the same capacitive coupling. The circuit acts as serial modem for the physical power line communication. The circuit and technique can be made of commercially available components or included in an application specific integrated circuit (ASIC) design, which allows for the circuit to be included in current designs with additional circuitry or embedded into new designs. This device and technique moves computational, sensing, and actuation abilities closer to the source, and allows for the networking of multiple similar nodes to each other and to a central processor. This technique also allows for reconfigurable systems by adding or removing nodes at any time. It can do so using nothing more than the in situ power wiring of the system.

Compensated gain control circuit for buck regulator command charge circuit

DOEpatents

Barrett, D.M.

1996-11-05

A buck regulator command charge circuit includes a compensated-gain control signal for compensating for changes in the component values in order to achieve optimal voltage regulation. The compensated-gain control circuit includes an automatic-gain control circuit for generating a variable-gain control signal. The automatic-gain control circuit is formed of a precision rectifier circuit, a filter network, an error amplifier, and an integrator circuit. 5 figs.

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

PubMed

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.

A three-limb amorphous magnetic circuit for three-phase 200 kVA distribution transformers

NASA Astrophysics Data System (ADS)

Kolano, R.; Wójcik, N.; Gawior, W.

1996-07-01

This paper describes the construction and method of preparation of a three-limb amorphous magnetic circuit. The circuit consists of three single cores: two smaller cores of the same size, surrounded by a third larger one with appropriate window dimensions. The no-load loss and exciting power of the single cores have been investigated as a function of the magnetic induction and stresses applied to the third core.

From Whole-Brain Data to Functional Circuit Models: The Zebrafish Optomotor Response.

PubMed

Naumann, Eva A; Fitzgerald, James E; Dunn, Timothy W; Rihel, Jason; Sompolinsky, Haim; Engert, Florian

2016-11-03

Detailed descriptions of brain-scale sensorimotor circuits underlying vertebrate behavior remain elusive. Recent advances in zebrafish neuroscience offer new opportunities to dissect such circuits via whole-brain imaging, behavioral analysis, functional perturbations, and network modeling. Here, we harness these tools to generate a brain-scale circuit model of the optomotor response, an orienting behavior evoked by visual motion. We show that such motion is processed by diverse neural response types distributed across multiple brain regions. To transform sensory input into action, these regions sequentially integrate eye- and direction-specific sensory streams, refine representations via interhemispheric inhibition, and demix locomotor instructions to independently drive turning and forward swimming. While experiments revealed many neural response types throughout the brain, modeling identified the dimensions of functional connectivity most critical for the behavior. We thus reveal how distributed neurons collaborate to generate behavior and illustrate a paradigm for distilling functional circuit models from whole-brain data. Copyright © 2016 Elsevier Inc. All rights reserved.

Sub-millimeter-Wave Equivalent Circuit Model for External Parasitics in Double-Finger HEMT Topologies

NASA Astrophysics Data System (ADS)

Karisan, Yasir; Caglayan, Cosan; Sertel, Kubilay

2018-02-01

We present a novel distributed equivalent circuit that incorporates a three-way-coupled transmission line to accurately capture the external parasitics of double-finger high electron mobility transistor (HEMT) topologies up to 750 GHz. A six-step systematic parameter extraction procedure is used to determine the equivalent circuit elements for a representative device layout. The accuracy of the proposed approach is validated in the 90-750 GHz band through comparisons between measured data (via non-contact probing) and full-wave simulations, as well as the equivalent circuit response. Subsequently, a semi-distributed active device model is incorporated into the proposed parasitic circuit to demonstrate that the three-way-coupled transmission line model effectively predicts the adverse effect of parasitic components on the sub-mmW performance in an amplifier setting.

Development of circuit model for arcing on solar panels

NASA Astrophysics Data System (ADS)

Mehta, Bhoomi K.; Deshpande, S. P.; Mukherjee, S.; Gupta, S. B.; Ranjan, M.; Rane, R.; Vaghela, N.; Acharya, V.; Sudhakar, M.; Sankaran, M.; Suresh, E. P.

2010-02-01

The increased requirements of payload capacity of the satellites have resulted in much higher power requirements of the satellites. In order to minimize the energy loss during power transmission due to cable loss, use of high voltage solar panels becomes necessary. When a satellite encounters space plasma it floats negatively with respect to the surrounding space plasma environment. At high voltage, charging and discharging on solar panels causes the power system breakdown. Once a solar panel surface is charged and potential difference between surface insulator and conductor exceeds certain value, electrostatic discharge (ESD) may occur. This ESD may trigger a secondary arc that can destroy the solar panel circuit. ESD is also called as primary or minor arc and secondary is called major arc. The energy of minor arc is supplied by the charge stored in the coverglass of solar array and is a pulse of typically several 100 ns to several 100 μs duration. The damage caused by minor arc is less compared to major arcs, but it is observed that the minor arc is cause of major arc. Therefore it is important to develop an understanding of minor arc and mitigation techniques. In this paper we present a linear circuit analysis for minor arcs on solar panels. To study arcing event, a ground experimental facility to simulate space plasma environment has been developed at Facilitation Centre for Industrial Plasma Technologies (Institute for Plasma Research) in collaboration with Indian Space Research Organization's ISRO Satellite Technology Centre (ISAC). A linear circuit model has been developed to explain the experimental results by representing the coverglass, solar cell interconnect and wiring by an LCR circuit and the primary arc by an equivalent LR circuit. The aim of the circuit analysis is to predict the arc current which flows through the arc plasma. It is established from the model that the current depends on various parameters like potential difference between insulator

Initial Testing of the Stainless Steel NaK-Cooled Circuit (SNaKC)

NASA Technical Reports Server (NTRS)

Garber, Anne; Godfroy, Thomas

2007-01-01

An actively pumped alkali metal flow circuit, designed and fabricated at the NASA Marshall Space Flight Center, is currently undergoing testing in the Early Flight Fission Test Facility (EFF-TF). Sodium potassium (NaK) was selected as the primary coolant. Basic circuit components include: simulated reactor core, NaK to gas heat exchanger, electromagnetic liquid metal pump, liquid metal flowmeter, load/drain reservoir, expansion reservoir, test section, and instrumentation. Operation of the circuit is based around the 37-pin partial-array core (pin and flow path dimensions are the same as those in a full core), designed to operate at 33 kWt. This presentation addresses the construction, fill and initial testing of the Stainless Steel NaK-Cooled Circuit (SNaKC).

Theoretical and Experimental Study of the Primary Current Distribution in Parallel-Plate Electrochemical Reactors

ERIC Educational Resources Information Center

Vazquez Aranda, Armando I.; Henquin, Eduardo R.; Torres, Israel Rodriguez; Bisang, Jose M.

2012-01-01

A laboratory experiment is described to determine the primary current distribution in parallel-plate electrochemical reactors. The electrolyte is simulated by conductive paper and the electrodes are segmented to measure the current distribution. Experiments are reported with the electrolyte confined to the interelectrode gap, where the current…

ADDER CIRCUIT

DOEpatents

Jacobsohn, D.H.; Merrill, L.C.

1959-01-20

An improved parallel addition unit is described which is especially adapted for use in electronic digital computers and characterized by propagation of the carry signal through each of a plurality of denominationally ordered stages within a minimum time interval. In its broadest aspects, the invention incorporates a fast multistage parallel digital adder including a plurality of adder circuits, carry-propagation circuit means in all but the most significant digit stage, means for conditioning each carry-propagation circuit during the time period in which information is placed into the adder circuits, and means coupling carry-generation portions of thc adder circuit to the carry propagating means.

46 CFR 28.365 - Overcurrent protection and switched circuits.

Code of Federal Regulations, 2011 CFR

2011-10-01

.... (c) Each ungrounded current carrying conductor must be protected in accordance with its current carrying capacity by a circuit breaker or fuse at the connection to the switchboard or distribution panel...

Color Coding of Circuit Quantities in Introductory Circuit Analysis Instruction

ERIC Educational Resources Information Center

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…

Design of an improved RCD buffer circuit for full bridge circuit

NASA Astrophysics Data System (ADS)

Yang, Wenyan; Wei, Xueye; Du, Yongbo; Hu, Liang; Zhang, Liwei; Zhang, Ou

2017-05-01

In the full bridge inverter circuit, when the switch tube suddenly opened or closed, the inductor current changes rapidly. Due to the existence of parasitic inductance of the main circuit. Therefore, the surge voltage between drain and source of the switch tube can be generated, which will have an impact on the switch and the output voltage. In order to ab sorb the surge voltage. An improve RCD buffer circuit is proposed in the paper. The peak energy will be absorbed through the buffer capacitor of the circuit. The part energy feedback to the power supply, another part release through the resistor in the form of heat, and the circuit can absorb the voltage spikes. This paper analyzes the process of the improved RCD snubber circuit, According to the specific parameters of the main circuit, a reasonable formula for calculating the resistance capacitance is given. A simulation model will be modulated in Multisim, which compared the waveform of tube voltage and the output waveform of the circuit without snubber circuit with the improved RCD snubber circuit. By comparing and analyzing, it is proved that the improved buffer circuit can absorb surge voltage. Finally, experiments are demonstrated to validate that the correctness of the RC formula and the improved RCD snubber circuit.

30 CFR 75.800-3 - Testing, examination and maintenance of circuit breakers; procedures.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Testing, examination and maintenance of circuit breakers; procedures. 75.800-3 Section 75.800-3 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... High-Voltage Distribution § 75.800-3 Testing, examination and maintenance of circuit breakers...

Fault-tolerant computer study. [logic designs for building block circuits

NASA Technical Reports Server (NTRS)

Rennels, D. A.; Avizienis, A. A.; Ercegovac, M. D.

1981-01-01

A set of building block circuits is described which can be used with commercially available microprocessors and memories to implement fault tolerant distributed computer systems. Each building block circuit is intended for VLSI implementation as a single chip. Several building blocks and associated processor and memory chips form a self checking computer module with self contained input output and interfaces to redundant communications buses. Fault tolerance is achieved by connecting self checking computer modules into a redundant network in which backup buses and computer modules are provided to circumvent failures. The requirements and design methodology which led to the definition of the building block circuits are discussed.

The circuit of polychromator for Experimental Advanced Superconducting Tokamak edge Thomson scattering diagnostic.

PubMed

Zang, Qing; Hsieh, C L; Zhao, Junyu; Chen, Hui; Li, Fengjuan

2013-09-01

The detector circuit is the core component of filter polychromator which is used for scattering light analysis in Thomson scattering diagnostic, and is responsible for the precision and stability of a system. High signal-to-noise and stability are primary requirements for the diagnostic. Recently, an upgraded detector circuit for weak light detecting in Experimental Advanced Superconducting Tokamak (EAST) edge Thomson scattering system has been designed, which can be used for the measurement of large electron temperature (T(e)) gradient and low electron density (n(e)). In this new circuit, a thermoelectric-cooled avalanche photodiode with the aid circuit is involved for increasing stability and enhancing signal-to-noise ratio (SNR), especially the circuit will never be influenced by ambient temperature. These features are expected to improve the accuracy of EAST Thomson diagnostic dramatically. Related mechanical construction of the circuit is redesigned as well for heat-sinking and installation. All parameters are optimized, and SNR is dramatically improved. The number of minimum detectable photons is only 10.

Teachers' Perception of Distributed Leadership in Hong Kong Primary Schools

ERIC Educational Resources Information Center

Wan, Sally Wai-Yan; Law, Edmond Hau-Fai; Chan, Keith Ki

2018-01-01

The purpose of the study is to examine Hong Kong teachers' perceptions of distributed leadership. Data were collected from six primary schools with a total of 155 teachers responding to a self-developed survey. Descriptive, reliability, and MANOVA data analyses were done with the application of the Statistical Package for Social Sciences (SPSS)…

Optical printed circuit board (O-PCB) and VLSI photonic integrated circuits: visions, challenges, and progresses

NASA Astrophysics Data System (ADS)

Lee, El-Hang; Lee, S. G.; O, B. H.; Park, S. G.; Noh, H. S.; Kim, K. H.; Song, S. H.

2006-09-01

A collective overview and review is presented on the original work conducted on the theory, design, fabrication, and in-tegration of micro/nano-scale optical wires and photonic devices for applications in a newly-conceived photonic systems called "optical printed circuit board" (O-PCBs) and "VLSI photonic integrated circuits" (VLSI-PIC). These are aimed for compact, high-speed, multi-functional, intelligent, light-weight, low-energy and environmentally friendly, low-cost, and high-volume applications to complement or surpass the capabilities of electrical PCBs (E-PCBs) and/or VLSI electronic integrated circuit (VLSI-IC) systems. These consist of 2-dimensional or 3-dimensional planar arrays of micro/nano-optical wires and circuits to perform the functions of all-optical sensing, storing, transporting, processing, switching, routing and distributing optical signals on flat modular boards or substrates. The integrated optical devices include micro/nano-scale waveguides, lasers, detectors, switches, sensors, directional couplers, multi-mode interference devices, ring-resonators, photonic crystal devices, plasmonic devices, and quantum devices, made of polymer, silicon and other semiconductor materials. For VLSI photonic integration, photonic crystals and plasmonic structures have been used. Scientific and technological issues concerning the processes of miniaturization, interconnection and integration of these systems as applicable to board-to-board, chip-to-chip, and intra-chip integration, are discussed along with applications for future computers, telecommunications, and sensor-systems. Visions and challenges toward these goals are also discussed.

Turkish Students' Conceptions about the Simple Electric Circuits

ERIC Educational Resources Information Center

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…

Optimization of discharge circuit of the TEA CO II laser with two discharge channels

NASA Astrophysics Data System (ADS)

Hu, Xiao Yong; Zhang, LiLi; Ren, DeMing; Qu, YanChen; Zhao, WeiJiang; Song, BaoAn

2007-01-01

In order to achieve the highest peak power of radiation pulse and highest output energy, the primary circuit parameters are investigated to optimize the discharge circuit performance of the laser. The structure and the discharge circuit of the laser are discussed at first. To realize synchronous discharge in two discharge channels, the conjunct electrode device for two pairs of discharge electrodes is designed. Finally, the results of the experiments on the primary circuit parameters are given. The discharge is most stable at a pressure of 5.33×10 4Pa when the pressure of gaseous mixture CO II:N II:He=1:1:3 is changed from 2.67×10 4 Pa to 6.67×10 4 Pa. The ratio of storage capacitance to peak capacitance is chosen to be about 1.5-7/3, because residual voltage is lower on this condition and residual voltage is adverse to discharge. When the inductance 330μH is used, the homogeneous glow discharge in a widest voltage range is obtained. The duration of when the stimuli voltage is increased in homogeneous glow discharge condition. The discharge circuit allows charge and discharge and the magnitude of residual voltage decrease the homogeneous glow discharge in a wide range of pressure of gaseous mixture when these circuit parameters are used. Thus it offers reference to the improvement of output characteristic of TEA CO II laser with two discharge channels.

High accuracy switched-current circuits using an improved dynamic mirror

NASA Technical Reports Server (NTRS)

Zweigle, G.; Fiez, T.

1991-01-01

The switched-current technique, a recently developed circuit approach to analog signal processing, has emerged as an alternative/compliment to the well established switched-capacitor circuit technique. High speed switched-current circuits offer potential cost and power savings over slower switched-capacitor circuits. Accuracy improvements are a primary concern at this stage in the development of the switched-current technique. Use of the dynamic current mirror has produced circuits that are insensitive to transistor matching errors. The dynamic current mirror has been limited by other sources of error including clock-feedthrough and voltage transient errors. In this paper we present an improved switched-current building block using the dynamic current mirror. Utilizing current feedback the errors due to current imbalance in the dynamic current mirror are reduced. Simulations indicate that this feedback can reduce total harmonic distortion by as much as 9 dB. Additionally, we have developed a clock-feedthrough reduction scheme for which simulations reveal a potential 10 dB total harmonic distortion improvement. The clock-feedthrough reduction scheme also significantly reduces offset errors and allows for cancellation with a constant current source. Experimental results confirm the simulated improvements.

VLSI circuits implementing computational models of neocortical circuits.

PubMed

Wijekoon, Jayawan H B; Dudek, Piotr

2012-09-15

This paper overviews the design and implementation of three neuromorphic integrated circuits developed for the COLAMN ("Novel Computing Architecture for Cognitive Systems based on the Laminar Microcircuitry of the Neocortex") project. The circuits are implemented in a standard 0.35 μm CMOS technology and include spiking and bursting neuron models, and synapses with short-term (facilitating/depressing) and long-term (STDP and dopamine-modulated STDP) dynamics. They enable execution of complex nonlinear models in accelerated-time, as compared with biology, and with low power consumption. The neural dynamics are implemented using analogue circuit techniques, with digital asynchronous event-based input and output. The circuits provide configurable hardware blocks that can be used to simulate a variety of neural networks. The paper presents experimental results obtained from the fabricated devices, and discusses the advantages and disadvantages of the analogue circuit approach to computational neural modelling. Copyright © 2012 Elsevier B.V. All rights reserved.

DISTRIBUTED RC NETWORKS WITH RATIONAL TRANSFER FUNCTIONS,

DTIC Science & Technology

A distributed RC circuit analogous to a continuously tapped transmission line can be made to have a rational short-circuit transfer admittance and...one rational shortcircuit driving-point admittance. A subcircuit of the same structure has a rational open circuit transfer impedance and one rational ...open circuit driving-point impedance. Hence, rational transfer functions may be obtained while considering either generator impedance or load

Synthesis of energy-efficient FSMs implemented in PLD circuits

NASA Astrophysics Data System (ADS)

Nawrot, Radosław; Kulisz, Józef; Kania, Dariusz

2017-11-01

The paper presents an outline of a simple synthesis method of energy-efficient FSMs. The idea consists in using local clock gating to selectively block the clock signal, if no transition of a state of a memory element is required. The research was dedicated to logic circuits using Programmable Logic Devices as the implementation platform, but the conclusions can be applied to any synchronous circuit. The experimental section reports a comparison of three methods of implementing sequential circuits in PLDs with respect to clock distribution: the classical fully synchronous structure, the structure exploiting the Enable Clock inputs of memory elements, and the structure using clock gating. The results show that the approach based on clock gating is the most efficient one, and it leads to significant reduction of dynamic power consumed by the FSM.

Current limiter circuit system

DOEpatents

Witcher, Joseph Brandon; Bredemann, Michael V.

2017-09-05

An apparatus comprising a steady state sensing circuit, a switching circuit, and a detection circuit. The steady state sensing circuit is connected to a first, a second and a third node. The first node is connected to a first device, the second node is connected to a second device, and the steady state sensing circuit causes a scaled current to flow at the third node. The scaled current is proportional to a voltage difference between the first and second node. The switching circuit limits an amount of current that flows between the first and second device. The detection circuit is connected to the third node and the switching circuit. The detection circuit monitors the scaled current at the third node and controls the switching circuit to limit the amount of the current that flows between the first and second device when the scaled current is greater than a desired level.

Spatial information outflow from the hippocampal circuit: distributed spatial coding and phase precession in the subiculum.

PubMed

Kim, Steve M; Ganguli, Surya; Frank, Loren M

2012-08-22

Hippocampal place cells convey spatial information through a combination of spatially selective firing and theta phase precession. The way in which this information influences regions like the subiculum that receive input from the hippocampus remains unclear. The subiculum receives direct inputs from area CA1 of the hippocampus and sends divergent output projections to many other parts of the brain, so we examined the firing patterns of rat subicular neurons. We found a substantial transformation in the subicular code for space from sparse to dense firing rate representations along a proximal-distal anatomical gradient: neurons in the proximal subiculum are more similar to canonical, sparsely firing hippocampal place cells, whereas neurons in the distal subiculum have higher firing rates and more distributed spatial firing patterns. Using information theory, we found that the more distributed spatial representation in the subiculum carries, on average, more information about spatial location and context than the sparse spatial representation in CA1. Remarkably, despite the disparate firing rate properties of subicular neurons, we found that neurons at all proximal-distal locations exhibit robust theta phase precession, with similar spiking oscillation frequencies as neurons in area CA1. Our findings suggest that the subiculum is specialized to compress sparse hippocampal spatial codes into highly informative distributed codes suitable for efficient communication to other brain regions. Moreover, despite this substantial compression, the subiculum maintains finer scale temporal properties that may allow it to participate in oscillatory phase coding and spike timing-dependent plasticity in coordination with other regions of the hippocampal circuit.

Trend in distribution of primary health care professionals in Jiangsu province of eastern China.

PubMed

Xu, Kang; Zhang, Kaijin; Wang, Dan; Zhou, Ling

2014-11-28

Since the late 1990 s, the Chinese government has carried out several reforms on the primary health care, which is greatly improved but still left much to be desired, especially for the health workforces. The aim of this study was to analyze the number of health workforces and the trends in distribution of health workforces in Jiangsu province of eastern China from 2008 to 2012. The time trends in number and distribution of health professionals were compared in study period. Lorenz curves were plotted and Gini coefficient, Atkinson index and Theil index were calculated for inequalities in the distribution of health workforces to population and area. The number of health workforces increased every year and the inequality in the distribution of health workforces showed a decline trend from 2008 to 2012. After 2009, these trends changed more rapidly. There was the disproportionality between physicians and nurses. The values of three inequality indicators based on area were larger than those based on population. The health reform in 2009 might play an important role in increasing the number of health workforces and improving the distribution of health workforces in primary health care facilities. The disproportionality between physicians and nurses was related to the shortage of number of nurses.

The circuit of polychromator for Experimental Advanced Superconducting Tokamak edge Thomson scattering diagnostic

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zang, Qing; Zhao, Junyu; Chen, Hui

2013-09-15

The detector circuit is the core component of filter polychromator which is used for scattering light analysis in Thomson scattering diagnostic, and is responsible for the precision and stability of a system. High signal-to-noise and stability are primary requirements for the diagnostic. Recently, an upgraded detector circuit for weak light detecting in Experimental Advanced Superconducting Tokamak (EAST) edge Thomson scattering system has been designed, which can be used for the measurement of large electron temperature (T{sub e}) gradient and low electron density (n{sub e}). In this new circuit, a thermoelectric-cooled avalanche photodiode with the aid circuit is involved for increasingmore » stability and enhancing signal-to-noise ratio (SNR), especially the circuit will never be influenced by ambient temperature. These features are expected to improve the accuracy of EAST Thomson diagnostic dramatically. Related mechanical construction of the circuit is redesigned as well for heat-sinking and installation. All parameters are optimized, and SNR is dramatically improved. The number of minimum detectable photons is only 10.« less

An electronic circuit that detects left ventricular ejection events by processing the arterial pressure waveform

NASA Technical Reports Server (NTRS)

Gebben, V. D.; Webb, J. A., Jr.

1972-01-01

An electronic circuit for processing arterial blood pressure waveform signals is described. The circuit detects blood pressure as the heart pumps blood through the aortic valve and the pressure distribution caused by aortic valve closure. From these measurements, timing signals for use in measuring the left ventricular ejection time is determined, and signals are provided for computer monitoring of the cardiovascular system. Illustrations are given of the circuit and pressure waveforms.

Coexistence of Multiple Attractors in an Active Diode Pair Based Chua’s Circuit

NASA Astrophysics Data System (ADS)

Bao, Bocheng; Wu, Huagan; Xu, Li; Chen, Mo; Hu, Wen

This paper focuses on the coexistence of multiple attractors in an active diode pair based Chua’s circuit with smooth nonlinearity. With dimensionless equations, dynamical properties, including boundness of system orbits and stability distributions of two nonzero equilibrium points, are investigated, and complex coexisting behaviors of multiple kinds of disconnected attractors of stable point attractors, limit cycles and chaotic attractors are numerically revealed. The results show that unlike the classical Chua’s circuit, the proposed circuit has two stable nonzero node-foci for the specified circuit parameters, thereby resulting in the emergence of multistability phenomenon. Based on two general impedance converters, the active diode pair based Chua’s circuit with an adjustable inductor and an adjustable capacitor is made in hardware, from which coexisting multiple attractors are conveniently captured.

Circuit-based versus full-wave modelling of active microwave circuits

NASA Astrophysics Data System (ADS)

Bukvić, Branko; Ilić, Andjelija Ž.; Ilić, Milan M.

2018-03-01

Modern full-wave computational tools enable rigorous simulations of linear parts of complex microwave circuits within minutes, taking into account all physical electromagnetic (EM) phenomena. Non-linear components and other discrete elements of the hybrid microwave circuit are then easily added within the circuit simulator. This combined full-wave and circuit-based analysis is a must in the final stages of the circuit design, although initial designs and optimisations are still faster and more comfortably done completely in the circuit-based environment, which offers real-time solutions at the expense of accuracy. However, due to insufficient information and general lack of specific case studies, practitioners still struggle when choosing an appropriate analysis method, or a component model, because different choices lead to different solutions, often with uncertain accuracy and unexplained discrepancies arising between the simulations and measurements. We here design a reconfigurable power amplifier, as a case study, using both circuit-based solver and a full-wave EM solver. We compare numerical simulations with measurements on the manufactured prototypes, discussing the obtained differences, pointing out the importance of measured parameters de-embedding, appropriate modelling of discrete components and giving specific recipes for good modelling practices.

Gate drive latching circuit for an auxiliary resonant commutation circuit

NASA Technical Reports Server (NTRS)

Delgado, Eladio Clemente (Inventor); Kheraluwala, Mustansir Hussainy (Inventor)

1999-01-01

A gate drive latching circuit for an auxiliary resonant commutation circuit for a power switching inverter includes a current monitor circuit providing a current signal to a pair of analog comparators to implement latching of one of a pair of auxiliary switching devices which are used to provide commutation current for commutating switching inverters in the circuit. Each of the pair of comparators feeds a latching circuit which responds to an active one of the comparators for latching the associated gate drive circuit for one of the pair of auxiliary commutating switches. An initial firing signal is applied to each of the commutating switches to gate each into conduction and the resulting current is monitored to determine current direction and therefore the one of the switches which is carrying current. The comparator provides a latching signal to the one of the auxiliary power switches which is actually conducting current and latches that particular power switch into an on state for the duration of current through the device. The latching circuit is so designed that the only time one of the auxiliary switching devices can be latched on is during the duration of an initial firing command signal.

Shared neural circuits for mentalizing about the self and others.

PubMed

Lombardo, Michael V; Chakrabarti, Bhismadev; Bullmore, Edward T; Wheelwright, Sally J; Sadek, Susan A; Suckling, John; Baron-Cohen, Simon

2010-07-01

Although many examples exist for shared neural representations of self and other, it is unknown how such shared representations interact with the rest of the brain. Furthermore, do high-level inference-based shared mentalizing representations interact with lower level embodied/simulation-based shared representations? We used functional neuroimaging (fMRI) and a functional connectivity approach to assess these questions during high-level inference-based mentalizing. Shared mentalizing representations in ventromedial prefrontal cortex, posterior cingulate/precuneus, and temporo-parietal junction (TPJ) all exhibited identical functional connectivity patterns during mentalizing of both self and other. Connectivity patterns were distributed across low-level embodied neural systems such as the frontal operculum/ventral premotor cortex, the anterior insula, the primary sensorimotor cortex, and the presupplementary motor area. These results demonstrate that identical neural circuits are implementing processes involved in mentalizing of both self and other and that the nature of such processes may be the integration of low-level embodied processes within higher level inference-based mentalizing.

Modifications and Modelling of the Fission Surface Power Primary Test Circuit (FSP-PTC)

NASA Technical Reports Server (NTRS)

Garber, Ann E.

2008-01-01

An actively pumped alkali metal flow circuit, designed and fabricated at the NASA Marshall Space Flight Center, underwent a range of tests at MSFC in early 2007. During this period, system transient responses and the performance of the liquid metal pump were evaluated. In May of 2007, the circuit was drained and cleaned to prepare for multiple modifications: the addition of larger upper and lower reservoirs, the installation of an annular linear induction pump (ALIP), and the inclusion of the Single Flow Cell Test Apparatus (SFCTA) in the test section. Performance of the ALIP, provided by Idaho National Laboratory (INL), will be evaluated when testing resumes. The SFCTA, which will be tested simultaneously, will provide data on alkali metal flow behavior through the simulated core channels and assist in the development of a second generation thermal simulator. Additionally, data from the first round of testing has been used to refine the working system model, developed using the Generalized Fluid System Simulation Program (GFSSP). This paper covers the modifications of the FSP-PTC and the updated GFSSP system model.

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

Code of Federal Regulations, 2010 CFR

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...

Distributed coupling and multi-frequency microwave accelerators

DOEpatents

Tantawi, Sami G.; Li, Zenghai; Borchard, Philipp

2016-07-05

A microwave circuit for a linear accelerator has multiple metallic cell sections, a pair of distribution waveguide manifolds, and a sequence of feed arms connecting the manifolds to the cell sections. The distribution waveguide manifolds are connected to the cell sections so that alternating pairs of cell sections are connected to opposite distribution waveguide manifolds. The distribution waveguide manifolds have concave modifications of their walls opposite the feed arms, and the feed arms have portions of two distinct widths. In some embodiments, the distribution waveguide manifolds are connected to the cell sections by two different types of junctions adapted to allow two frequency operation. The microwave circuit may be manufactured by making two quasi-identical parts, and joining the two parts to form the microwave circuit, thereby allowing for many manufacturing techniques including electron beam welding, and thereby allowing the use of un-annealled copper alloys, and hence greater tolerance to high gradient operation.

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

Code of Federal Regulations, 2010 CFR

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...

Early Disruption of Extracellular Pleiotrophin Distribution Alters Cerebellar Neuronal Circuit Development and Function.

PubMed

Hamza, M M; Rey, S A; Hilber, P; Arabo, A; Collin, T; Vaudry, D; Burel, D

2016-10-01

The cerebellum is a structure of the central nervous system involved in balance, motor coordination, and voluntary movements. The elementary circuit implicated in the control of locomotion involves Purkinje cells, which receive excitatory inputs from parallel and climbing fibers, and are regulated by cerebellar interneurons. In mice as in human, the cerebellar cortex completes its development mainly after birth with the migration, differentiation, and synaptogenesis of granule cells. These cellular events are under the control of numerous extracellular matrix molecules including pleiotrophin (PTN). This cytokine has been shown to regulate the morphogenesis of Purkinje cells ex vivo and in vivo via its receptor PTPζ. Since Purkinje cells are the unique output of the cerebellar cortex, we explored the consequences of their PTN-induced atrophy on the function of the cerebellar neuronal circuit in mice. Behavioral experiments revealed that, despite a normal overall development, PTN-treated mice present a delay in the maturation of their flexion reflex. Moreover, patch clamp recording of Purkinje cells revealed a significant increase in the frequency of spontaneous excitatory postsynaptic currents in PTN-treated mice, associated with a decrease of climbing fiber innervations and an abnormal perisomatic localization of the parallel fiber contacts. At adulthood, PTN-treated mice exhibit coordination impairment on the rotarod test associated with an alteration of the synchronization gait. Altogether these histological, electrophysiological, and behavior data reveal that an early ECM disruption of PTN composition induces short- and long-term defaults in the establishment of proper functional cerebellar circuit.

Inequality in the distribution of health resources and health services in China: hospitals versus primary care institutions.

PubMed

Zhang, Tao; Xu, Yongjian; Ren, Jianping; Sun, Liqi; Liu, Chaojie

2017-03-03

Equity is one of the major goals of China's recent health system reform. This study aimed to evaluate the equality of the distribution of health resources and health services between hospitals and primary care institutions. Data of this study were drawn from the China Health Statistical Year Books. We calculated Gini coefficients based on population size and geographic size, respectively, for the indicators: number of institutions, number of health workers and number of beds; and the concentration index (CI) for the indicators: per capita outpatient visits and annual hospitalization rates. The Gini coefficients against population size ranged between 0.17 and 0.44 in the hospital sector, indicating a relatively good equality. The primary care sector showed a slightly higher level of Gini coefficients (around 0.45) in the number of health workers. However, inequality was evident in the geographic distribution of health resources. The Gini coefficients exceeded 0.7 in the geographic distribution of institutions, health workers and beds in both the hospital and the primary care sectors, indicating high levels of inequality. The CI values of hospital inpatient care and outpatient visits to primary care institutions were small (ranging from -0.02 to 0.02), indicating good wealth-related equality. The CI values of outpatient visits to hospitals ranged from 0.16 to 0.21, indicating a concentration of services towards the richer populations. By contrast, the CI values of inpatient care in primary care institutions ranged from -0.24 to -0.22, indicating a concentration of services towards the poorer populations. The eastern developed region also had a high internal inequality compared with the other less developed regions. Significant inequality in the geographic distribution of health resources is evident, despite a more equitable per capita distribution of resources. Richer people are more likely to use well-resourced hospitals for outpatient care. By contrast, poorer

Three-phase short circuit calculation method based on pre-computed surface for doubly fed induction generator

NASA Astrophysics Data System (ADS)

Ma, J.; Liu, Q.

2018-02-01

This paper presents an improved short circuit calculation method, based on pre-computed surface to determine the short circuit current of a distribution system with multiple doubly fed induction generators (DFIGs). The short circuit current, injected into power grid by DFIG, is determined by low voltage ride through (LVRT) control and protection under grid fault. However, the existing methods are difficult to calculate the short circuit current of DFIG in engineering practice due to its complexity. A short circuit calculation method, based on pre-computed surface, was proposed by developing the surface of short circuit current changing with the calculating impedance and the open circuit voltage. And the short circuit currents were derived by taking into account the rotor excitation and crowbar activation time. Finally, the pre-computed surfaces of short circuit current at different time were established, and the procedure of DFIG short circuit calculation considering its LVRT was designed. The correctness of proposed method was verified by simulation.

Thermocouple-Signal-Conditioning Circuit

NASA Technical Reports Server (NTRS)

Simon, Richard A.

1991-01-01

Thermocouple-signal-conditioning circuit acting in conjunction with thermocouple, exhibits electrical behavior of voltage in series with resistance. Combination part of input bridge circuit of controller. Circuit configured for either of two specific applications by selection of alternative resistances and supply voltages. Includes alarm circuit detecting open circuit in thermocouple and provides off-scale output to signal malfunctions.

Intracortical circuits amplify sound-evoked activity in primary auditory cortex following systemic injection of salicylate in the rat

PubMed Central

Chrostowski, Michael; Salvi, Richard J.; Allman, Brian L.

2012-01-01

A high dose of sodium salicylate temporarily induces tinnitus, mild hearing loss, and possibly hyperacusis in humans and other animals. Salicylate has well-established effects on cochlear function, primarily resulting in the moderate reduction of auditory input to the brain. Despite decreased peripheral sensitivity and output, salicylate induces a paradoxical enhancement of the sound-evoked field potential at the level of the primary auditory cortex (A1). Previous electrophysiologic studies have begun to characterize changes in thalamorecipient layers of A1; however, A1 is a complex neural circuit with recurrent intracortical connections. To describe the effects of acute systemic salicylate treatment on both thalamic and intracortical sound-driven activity across layers of A1, we applied current-source density (CSD) analysis to field potentials sampled across cortical layers in the anesthetized rat. CSD maps were normally characterized by a large, short-latency, monosynaptic, thalamically driven sink in granular layers followed by a lower amplitude, longer latency, polysynaptic, intracortically driven sink in supragranular layers. Following systemic administration of salicylate, there was a near doubling of both granular and supragranular sink amplitudes at higher sound levels. The supragranular sink amplitude input/output function changed from becoming asymptotic at approximately 50 dB to sharply nonasymptotic, often dominating the granular sink amplitude at higher sound levels. The supragranular sink also exhibited a significant decrease in peak latency, reflecting an acceleration of intracortical processing of the sound-evoked response. Additionally, multiunit (MU) activity was altered by salicylate; the normally onset/sustained MU response type was transformed into a primarily onset response type in granular and infragranular layers. The results from CSD analysis indicate that salicylate significantly enhances sound-driven response via intracortical circuits

Engineering a robust DNA split proximity circuit with minimized circuit leakage

PubMed Central

Ang, Yan Shan; Tong, Rachel; Yung, Lin-Yue Lanry

2016-01-01

DNA circuit is a versatile and highly-programmable toolbox which can potentially be used for the autonomous sensing of dynamic events, such as biomolecular interactions. However, the experimental implementation of in silico circuit designs has been hindered by the problem of circuit leakage. Here, we systematically analyzed the sources and characteristics of various types of leakage in a split proximity circuit which was engineered to spatially probe for target sites held within close proximity. Direct evidence that 3′-truncated oligonucleotides were the major impurity contributing to circuit leakage was presented. More importantly, a unique strategy of translocating a single nucleotide between domains, termed ‘inter-domain bridging’, was introduced to eliminate toehold-independent leakages while enhancing the strand displacement kinetics across a three-way junction. We also analyzed the dynamics of intermediate complexes involved in the circuit computation in order to define the working range of domain lengths for the reporter toehold and association region respectively. The final circuit design was successfully implemented on a model streptavidin-biotin system and demonstrated to be robust against both circuit leakage and biological interferences. We anticipate that this simple signal transduction strategy can be used to probe for diverse biomolecular interactions when used in conjunction with specific target recognition moieties. PMID:27207880

Temperature-Dependent Short-Circuit Capability of Silicon Carbide Power MOSFETs

DOE PAGES

Wang, Zhiqiang; Shi, Xiaojie; Tolbert, Leon M.; ...

2016-02-01

Our paper presents a comprehensive short-circuit ruggedness evaluation and numerical investigation of up-to-date commercial silicon carbide (SiC) MOSFETs. The short-circuit capability of three types of commercial 1200-V SiC MOSFETs is tested under various conditions, with case temperatures from 25 to 200 degrees C and dc bus voltages from 400 to 750 V. It is found that the commercial SiC MOSFETs can withstand short-circuit current for only several microseconds with a dc bus voltage of 750 V and case temperature of 200 degrees C. Moreover, the experimental short-circuit behaviors are compared, and analyzed through numerical thermal dynamic simulation. Specifically, an electrothermalmore » model is built to estimate the device internal temperature distribution, considering the temperature-dependent thermal properties of SiC material. Based on the temperature information, a leakage current model is derived to calculate the main leakage current components (i.e., thermal, diffusion, and avalanche generation currents). Finally, numerical results show that the short-circuit failure mechanisms of SiC MOSFETs can be thermal generation current induced thermal runaway or high-temperature-related gate oxide damage.« less

SEMICONDUCTOR INTEGRATED CIRCUITS: A quasi-3-dimensional simulation method for a high-voltage level-shifting circuit structure

NASA Astrophysics Data System (ADS)

Jizhi, Liu; Xingbi, Chen

2009-12-01

A new quasi-three-dimensional (quasi-3D) numeric simulation method for a high-voltage level-shifting circuit structure is proposed. The performances of the 3D structure are analyzed by combining some 2D device structures; the 2D devices are in two planes perpendicular to each other and to the surface of the semiconductor. In comparison with Davinci, the full 3D device simulation tool, the quasi-3D simulation method can give results for the potential and current distribution of the 3D high-voltage level-shifting circuit structure with appropriate accuracy and the total CPU time for simulation is significantly reduced. The quasi-3D simulation technique can be used in many cases with advantages such as saving computing time, making no demands on the high-end computer terminals, and being easy to operate.

Development, Integration and Testing of Automated Triggering Circuit for Hybrid DC Circuit Breaker

NASA Astrophysics Data System (ADS)

Kanabar, Deven; Roy, Swati; Dodiya, Chiragkumar; Pradhan, Subrata

2017-04-01

A novel concept of Hybrid DC circuit breaker having combination of mechanical switch and static switch provides arc-less current commutation into the dump resistor during quench in superconducting magnet operation. The triggering of mechanical and static switches in Hybrid DC breaker can be automatized which can effectively reduce the overall current commutation time of hybrid DC circuit breaker and make the operation independent of opening time of mechanical switch. With this view, a dedicated control circuit (auto-triggering circuit) has been developed which can decide the timing and pulse duration for mechanical switch as well as static switch from the operating parameters. This circuit has been tested with dummy parameters and thereafter integrated with the actual test set up of hybrid DC circuit breaker. This paper deals with the conceptual design of the auto-triggering circuit, its control logic and operation. The test results of Hybrid DC circuit breaker using this circuit have also been discussed.

The Italian primary school-size distribution and the city-size: a complex nexus

PubMed Central

Belmonte, Alessandro; Di Clemente, Riccardo; Buldyrev, Sergey V.

2014-01-01

We characterize the statistical law according to which Italian primary school-size distributes. We find that the school-size can be approximated by a log-normal distribution, with a fat lower tail that collects a large number of very small schools. The upper tail of the school-size distribution decreases exponentially and the growth rates are distributed with a Laplace PDF. These distributions are similar to those observed for firms and are consistent with a Bose-Einstein preferential attachment process. The body of the distribution features a bimodal shape suggesting some source of heterogeneity in the school organization that we uncover by an in-depth analysis of the relation between schools-size and city-size. We propose a novel cluster methodology and a new spatial interaction approach among schools which outline the variety of policies implemented in Italy. Different regional policies are also discussed shedding lights on the relation between policy and geographical features. PMID:24954714

The Italian primary school-size distribution and the city-size: a complex nexus

NASA Astrophysics Data System (ADS)

Belmonte, Alessandro; di Clemente, Riccardo; Buldyrev, Sergey V.

2014-06-01

We characterize the statistical law according to which Italian primary school-size distributes. We find that the school-size can be approximated by a log-normal distribution, with a fat lower tail that collects a large number of very small schools. The upper tail of the school-size distribution decreases exponentially and the growth rates are distributed with a Laplace PDF. These distributions are similar to those observed for firms and are consistent with a Bose-Einstein preferential attachment process. The body of the distribution features a bimodal shape suggesting some source of heterogeneity in the school organization that we uncover by an in-depth analysis of the relation between schools-size and city-size. We propose a novel cluster methodology and a new spatial interaction approach among schools which outline the variety of policies implemented in Italy. Different regional policies are also discussed shedding lights on the relation between policy and geographical features.

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

PubMed

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

2012-09-01

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

Fault diagnosis for analog circuits utilizing time-frequency features and improved VVRKFA

NASA Astrophysics Data System (ADS)

He, Wei; He, Yigang; Luo, Qiwu; Zhang, Chaolong

2018-04-01

This paper proposes a novel scheme for analog circuit fault diagnosis utilizing features extracted from the time-frequency representations of signals and an improved vector-valued regularized kernel function approximation (VVRKFA). First, the cross-wavelet transform is employed to yield the energy-phase distribution of the fault signals over the time and frequency domain. Since the distribution is high-dimensional, a supervised dimensionality reduction technique—the bilateral 2D linear discriminant analysis—is applied to build a concise feature set from the distributions. Finally, VVRKFA is utilized to locate the fault. In order to improve the classification performance, the quantum-behaved particle swarm optimization technique is employed to gradually tune the learning parameter of the VVRKFA classifier. The experimental results for the analog circuit faults classification have demonstrated that the proposed diagnosis scheme has an advantage over other approaches.

Stripline/Microstrip Transition in Multilayer Circuit Board

NASA Technical Reports Server (NTRS)

Epp, Larry; Khan, Abdur

2005-01-01

A stripline-to-microstrip transition has been incorporated into a multilayer circuit board that supports a distributed solid-state microwave power amplifier, for the purpose of coupling the microwave signal from a buried-layer stripline to a top-layer microstrip. The design of the transition could be adapted to multilayer circuit boards in such products as cellular telephones (for connecting between circuit-board signal lines and antennas), transmitters for Earth/satellite communication systems, and computer mother boards (if processor speeds increase into the range of tens of gigahertz). The transition is designed to satisfy the following requirements in addition to the basic coupling requirement described above: (1) The transition must traverse multiple layers, including intermediate layers that contain DC circuitry. (2) The transition must work at a frequency of 32 GHz with low loss and low reflection. (3) The power delivered by the transition to top-layer microstrip must be split equally in opposite directions along the microstrip. Referring to the figure, this amounts to a requirement that when power is supplied to input port 1, equal amounts of power flow through output ports 2 and 3. (4) The signal-line via that is necessarily a part of such a transition must not be what is known in the art as a blind via; that is, it must span the entire thickness of the circuit board.

Approximate circuits for increased reliability

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hamlet, Jason R.; Mayo, Jackson R.

2015-08-18

Embodiments of the invention describe a Boolean circuit having a voter circuit and a plurality of approximate circuits each based, at least in part, on a reference circuit. The approximate circuits are each to generate one or more output signals based on values of received input signals. The voter circuit is to receive the one or more output signals generated by each of the approximate circuits, and is to output one or more signals corresponding to a majority value of the received signals. At least some of the approximate circuits are to generate an output value different than the referencemore » circuit for one or more input signal values; however, for each possible input signal value, the majority values of the one or more output signals generated by the approximate circuits and received by the voter circuit correspond to output signal result values of the reference circuit.« less

Waveshaping electronic circuit

NASA Technical Reports Server (NTRS)

Harper, T. P.

1971-01-01

Circuit provides output signal with sinusoidal function in response to bipolar transition of input signal. Instantaneous transition shapes into linear rate of change and linear rate of change shapes into sinusoidal rate of change. Circuit contains only active components; therefore, compatibility with integrated circuit techniques is assured.

Design of low loss helix circuits for interference fitted and brazed circuits

NASA Technical Reports Server (NTRS)

Jacquez, A.

1983-01-01

The RF loss properties and thermal capability of brazed helix circuits and interference fitted circuits were evaluated. The objective was to produce design circuits with minimum RF loss and maximum heat transfer. These circuits were to be designed to operate at 10 kV and at 20 GHz using a gamma a approximately equal to 1.0. This represents a circuit diameter of only 0.75 millimeters. The fabrication of this size circuit and the 0.48 millimeter high support rods required considerable refinements in the assembly techniques and fixtures used on lower frequency circuits. The transition from the helices to the waveguide was designed and the circuits were matched from 20 to 40 GHz since the helix design is a broad band circuit and at a gamma a of 1.0 will operate over this band. The loss measurement was a transmission measurement and therefore had two such transitions. This resulting double-ended match required tuning elements to achieve the broad band match and external E-H tuners at each end to optimize the match for each frequency where the loss measurement was made. The test method used was a substitution method where the test fixture was replaced by a calibrated attenuator.

Cell type-specific genetic and optogenetic tools reveal hippocampal CA2 circuits.

PubMed

Kohara, Keigo; Pignatelli, Michele; Rivest, Alexander J; Jung, Hae-Yoon; Kitamura, Takashi; Suh, Junghyup; Frank, Dominic; Kajikawa, Koichiro; Mise, Nathan; Obata, Yuichi; Wickersham, Ian R; Tonegawa, Susumu

2014-02-01

The formation and recall of episodic memory requires precise information processing by the entorhinal-hippocampal network. For several decades, the trisynaptic circuit entorhinal cortex layer II (ECII)→dentate gyrus→CA3→CA1 and the monosynaptic circuit ECIII→CA1 have been considered the primary substrates of the network responsible for learning and memory. Circuits linked to another hippocampal region, CA2, have only recently come to light. Using highly cell type-specific transgenic mouse lines, optogenetics and patch-clamp recordings, we found that dentate gyrus cells, long believed to not project to CA2, send functional monosynaptic inputs to CA2 pyramidal cells through abundant longitudinal projections. CA2 innervated CA1 to complete an alternate trisynaptic circuit, but, unlike CA3, projected preferentially to the deep, rather than to the superficial, sublayer of CA1. Furthermore, contrary to existing knowledge, ECIII did not project to CA2. Our results allow a deeper understanding of the biology of learning and memory.

Distributed Circuit Plasticity: New Clues for the Cerebellar Mechanisms of Learning.

PubMed

D'Angelo, Egidio; Mapelli, Lisa; Casellato, Claudia; Garrido, Jesus A; Luque, Niceto; Monaco, Jessica; Prestori, Francesca; Pedrocchi, Alessandra; Ros, Eduardo

2016-04-01

The cerebellum is involved in learning and memory of sensory motor skills. However, the way this process takes place in local microcircuits is still unclear. The initial proposal, casted into the Motor Learning Theory, suggested that learning had to occur at the parallel fiber-Purkinje cell synapse under supervision of climbing fibers. However, the uniqueness of this mechanism has been questioned, and multiple forms of long-term plasticity have been revealed at various locations in the cerebellar circuit, including synapses and neurons in the granular layer, molecular layer and deep-cerebellar nuclei. At present, more than 15 forms of plasticity have been reported. There has been a long debate on which plasticity is more relevant to specific aspects of learning, but this question turned out to be hard to answer using physiological analysis alone. Recent experiments and models making use of closed-loop robotic simulations are revealing a radically new view: one single form of plasticity is insufficient, while altogether, the different forms of plasticity can explain the multiplicity of properties characterizing cerebellar learning. These include multi-rate acquisition and extinction, reversibility, self-scalability, and generalization. Moreover, when the circuit embeds multiple forms of plasticity, it can easily cope with multiple behaviors endowing therefore the cerebellum with the properties needed to operate as an effective generalized forward controller.

Towards circuit optogenetics.

PubMed

Chen, I-Wen; Papagiakoumou, Eirini; Emiliani, Valentina

2018-06-01

Optogenetics neuronal targeting combined with single-photon wide-field illumination has already proved its enormous potential in neuroscience, enabling the optical control of entire neuronal networks and disentangling their role in the control of specific behaviors. However, establishing how a single or a sub-set of neurons controls a specific behavior, or how functionally identical neurons are connected in a particular task, or yet how behaviors can be modified in real-time by the complex wiring diagram of neuronal connections requires more sophisticated approaches enabling to drive neuronal circuits activity with single-cell precision and millisecond temporal resolution. This has motivated on one side the development of flexible optical methods for two-photon (2P) optogenetic activation using either, or a hybrid of two approaches: scanning and parallel illumination. On the other side, it has stimulated the engineering of new opsins with modified spectral characteristics, channel kinetics and spatial distribution of expression, offering the necessary flexibility of choosing the appropriate opsin for each application. The need for optical manipulation of multiple targets with millisecond temporal resolution has imposed three-dimension (3D) parallel holographic illumination as the technique of choice for optical control of neuronal circuits organized in 3D. Today 3D parallel illumination exists in several complementary variants, each with a different degree of simplicity, light uniformity, temporal precision and axial resolution. In parallel, the possibility to reach hundreds of targets in 3D volumes has prompted the development of low-repetition rate amplified laser sources enabling high peak power, while keeping low average power for stimulating each cell. All together those progresses open the way for a precise optical manipulation of neuronal circuits with unprecedented precision and flexibility. Copyright © 2018 Elsevier Ltd. All rights reserved.

Laminar circuit organization and response modulation in mouse visual cortex

PubMed Central

Olivas, Nicholas D.; Quintanar-Zilinskas, Victor; Nenadic, Zoran; Xu, Xiangmin

2012-01-01

The mouse has become an increasingly important animal model for visual system studies, but few studies have investigated local functional circuit organization of mouse visual cortex. Here we used our newly developed mapping technique combining laser scanning photostimulation (LSPS) with fast voltage-sensitive dye (VSD) imaging to examine the spatial organization and temporal dynamics of laminar circuit responses in living slice preparations of mouse primary visual cortex (V1). During experiments, LSPS using caged glutamate provided spatially restricted neuronal activation in a specific cortical layer, and evoked responses from the stimulated layer to its functionally connected regions were detected by VSD imaging. In this study, we first provided a detailed analysis of spatiotemporal activation patterns at specific V1 laminar locations and measured local circuit connectivity. Then we examined the role of cortical inhibition in the propagation of evoked cortical responses by comparing circuit activity patterns in control and in the presence of GABAa receptor antagonists. We found that GABAergic inhibition was critical in restricting layer-specific excitatory activity spread and maintaining topographical projections. In addition, we investigated how AMPA and NMDA receptors influenced cortical responses and found that blocking AMPA receptors abolished interlaminar functional projections, and the NMDA receptor activity was important in controlling visual cortical circuit excitability and modulating activity propagation. The NMDA receptor antagonist reduced neuronal population activity in time-dependent and laminar-specific manners. Finally, we used the quantitative information derived from the mapping experiments and presented computational modeling analysis of V1 circuit organization. Taken together, the present study has provided important new information about mouse V1 circuit organization and response modulation. PMID:23060751

30 CFR 77.803 - Fail safe ground check circuits on high-voltage resistance grounded systems.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Fail safe ground check circuits on high-voltage... WORK AREAS OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.803 Fail safe ground check..., resistance grounded systems shall include a fail safe ground check circuit or other no less effective device...

30 CFR 77.803 - Fail safe ground check circuits on high-voltage resistance grounded systems.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fail safe ground check circuits on high-voltage... WORK AREAS OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.803 Fail safe ground check..., resistance grounded systems shall include a fail safe ground check circuit or other no less effective device...

30 CFR 77.803 - Fail safe ground check circuits on high-voltage resistance grounded systems.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Fail safe ground check circuits on high-voltage... WORK AREAS OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.803 Fail safe ground check..., resistance grounded systems shall include a fail safe ground check circuit or other no less effective device...

30 CFR 77.803 - Fail safe ground check circuits on high-voltage resistance grounded systems.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Fail safe ground check circuits on high-voltage... WORK AREAS OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.803 Fail safe ground check..., resistance grounded systems shall include a fail safe ground check circuit or other no less effective device...

Parallelizing quantum circuit synthesis

NASA Astrophysics Data System (ADS)

Di Matteo, Olivia; Mosca, Michele

2016-03-01

Quantum circuit synthesis is the process in which an arbitrary unitary operation is decomposed into a sequence of gates from a universal set, typically one which a quantum computer can implement both efficiently and fault-tolerantly. As physical implementations of quantum computers improve, the need is growing for tools that can effectively synthesize components of the circuits and algorithms they will run. Existing algorithms for exact, multi-qubit circuit synthesis scale exponentially in the number of qubits and circuit depth, leaving synthesis intractable for circuits on more than a handful of qubits. Even modest improvements in circuit synthesis procedures may lead to significant advances, pushing forward the boundaries of not only the size of solvable circuit synthesis problems, but also in what can be realized physically as a result of having more efficient circuits. We present a method for quantum circuit synthesis using deterministic walks. Also termed pseudorandom walks, these are walks in which once a starting point is chosen, its path is completely determined. We apply our method to construct a parallel framework for circuit synthesis, and implement one such version performing optimal T-count synthesis over the Clifford+T gate set. We use our software to present examples where parallelization offers a significant speedup on the runtime, as well as directly confirm that the 4-qubit 1-bit full adder has optimal T-count 7 and T-depth 3.

Sequential circuit design for radiation hardened multiple voltage integrated circuits

DOEpatents

Clark, Lawrence T [Phoenix, AZ; McIver, III, John K.

2009-11-24

The present invention includes a radiation hardened sequential circuit, such as a bistable circuit, flip-flop or other suitable design that presents substantial immunity to ionizing radiation while simultaneously maintaining a low operating voltage. In one embodiment, the circuit includes a plurality of logic elements that operate on relatively low voltage, and a master and slave latches each having storage elements that operate on a relatively high voltage.

Engineering-Aligned 3D Neural Circuit in Microfluidic Device.

PubMed

Bang, Seokyoung; Na, Sangcheol; Jang, Jae Myung; Kim, Jinhyun; Jeon, Noo Li

2016-01-07

The brain is one of the most important and complex organs in the human body. Although various neural network models have been proposed for in vitro 3D neuronal networks, it has been difficult to mimic functional and structural complexity of the in vitro neural circuit. Here, a microfluidic model of a simplified 3D neural circuit is reported. First, the microfluidic device is filled with Matrigel and continuous flow is delivered across the device during gelation. The fluidic flow aligns the extracellular matrix (ECM) components along the flow direction. Following the alignment of ECM fibers, neurites of primary rat cortical neurons are grown into the Matrigel at the average speed of 250 μm d(-1) and form axon bundles approximately 1500 μm in length at 6 days in vitro (DIV). Additionally, neural networks are developed from presynaptic to postsynaptic neurons at 14 DIV. The establishment of aligned 3D neural circuits is confirmed with the immunostaining of PSD-95 and synaptophysin and the observation of calcium signal transmission. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Genetic circuit design automation.

PubMed

Nielsen, Alec A K; Der, Bryan S; Shin, Jonghyeon; Vaidyanathan, Prashant; Paralanov, Vanya; Strychalski, Elizabeth A; Ross, David; Densmore, Douglas; Voigt, Christopher A

2016-04-01

Computation can be performed in living cells by DNA-encoded circuits that process sensory information and control biological functions. Their construction is time-intensive, requiring manual part assembly and balancing of regulator expression. We describe a design environment, Cello, in which a user writes Verilog code that is automatically transformed into a DNA sequence. Algorithms build a circuit diagram, assign and connect gates, and simulate performance. Reliable circuit design requires the insulation of gates from genetic context, so that they function identically when used in different circuits. We used Cello to design 60 circuits forEscherichia coli(880,000 base pairs of DNA), for which each DNA sequence was built as predicted by the software with no additional tuning. Of these, 45 circuits performed correctly in every output state (up to 10 regulators and 55 parts), and across all circuits 92% of the output states functioned as predicted. Design automation simplifies the incorporation of genetic circuits into biotechnology projects that require decision-making, control, sensing, or spatial organization. Copyright © 2016, American Association for the Advancement of Science.

Piezoelectric drive circuit

DOEpatents

Treu, Jr., Charles A.

1999-08-31

A piezoelectric motor drive circuit is provided which utilizes the piezoelectric elements as oscillators and a Meacham half-bridge approach to develop feedback from the motor ground circuit to produce a signal to drive amplifiers to power the motor. The circuit automatically compensates for shifts in harmonic frequency of the piezoelectric elements due to pressure and temperature changes.

30 CFR 75.601-1 - Short circuit protection; ratings and settings of circuit breakers.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Trailing Cables § 75.601-1 Short circuit protection; ratings and settings of circuit breakers. Circuit breakers providing short circuit protection for trailing cables shall be set so as not to exceed the...

CUGatesDensity—Quantum circuit analyser extended to density matrices

NASA Astrophysics Data System (ADS)

Loke, T.; Wang, J. B.

2013-12-01

CUGatesDensity is an extension of the original quantum circuit analyser CUGates (Loke and Wang, 2011) [7] to provide explicit support for the use of density matrices. The new package enables simulation of quantum circuits involving statistical ensemble of mixed quantum states. Such analysis is of vital importance in dealing with quantum decoherence, measurements, noise and error correction, and fault tolerant computation. Several examples involving mixed state quantum computation are presented to illustrate the use of this package. Catalogue identifier: AEPY_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEPY_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 5368 No. of bytes in distributed program, including test data, etc.: 143994 Distribution format: tar.gz Programming language: Mathematica. Computer: Any computer installed with a copy of Mathematica 6.0 or higher. Operating system: Any system with a copy of Mathematica 6.0 or higher installed. Classification: 4.15. Nature of problem: To simulate arbitrarily complex quantum circuits comprised of single/multiple qubit and qudit quantum gates with mixed state registers. Solution method: A density matrix representation for mixed states and a state vector representation for pure states are used. The construct is based on an irreducible form of matrix decomposition, which allows a highly efficient implementation of general controlled gates with multiple conditionals. Running time: The examples provided in the notebook CUGatesDensity.nb take approximately 30 s to run on a laptop PC.

Full circuit calculation for electromagnetic pulse transmission in a high current facility

NASA Astrophysics Data System (ADS)

Zou, Wenkang; Guo, Fan; Chen, Lin; Song, Shengyi; Wang, Meng; Xie, Weiping; Deng, Jianjun

2014-11-01

We describe herein for the first time a full circuit model for electromagnetic pulse transmission in the Primary Test Stand (PTS)—the first TW class pulsed power driver in China. The PTS is designed to generate 8-10 MA current into a z -pinch load in nearly 90 ns rise time for inertial confinement fusion and other high energy density physics research. The PTS facility has four conical magnetic insulation transmission lines, in which electron current loss exists during the establishment of magnetic insulation. At the same time, equivalent resistance of switches and equivalent inductance of pinch changes with time. However, none of these models are included in a commercially developed circuit code so far. Therefore, in order to characterize the electromagnetic transmission process in the PTS, a full circuit model, in which switch resistance, magnetic insulation transmission line current loss and a time-dependent load can be taken into account, was developed. Circuit topology and an equivalent circuit model of the facility were introduced. Pulse transmission calculation of shot 0057 was demonstrated with the corresponding code FAST (full-circuit analysis and simulation tool) by setting controllable parameters the same as in the experiment. Preliminary full circuit simulation results for electromagnetic pulse transmission to the load are presented. Although divergences exist between calculated and experimentally obtained waveforms before the vacuum section, consistency with load current is satisfactory, especially at the rising edge.

Distribution system model calibration with big data from AMI and PV inverters

DOE PAGES

Peppanen, Jouni; Reno, Matthew J.; Broderick, Robert J.; ...

2016-03-03

Efficient management and coordination of distributed energy resources with advanced automation schemes requires accurate distribution system modeling and monitoring. Big data from smart meters and photovoltaic (PV) micro-inverters can be leveraged to calibrate existing utility models. This paper presents computationally efficient distribution system parameter estimation algorithms to improve the accuracy of existing utility feeder radial secondary circuit model parameters. The method is demonstrated using a real utility feeder model with advanced metering infrastructure (AMI) and PV micro-inverters, along with alternative parameter estimation approaches that can be used to improve secondary circuit models when limited measurement data is available. Lastly, themore » parameter estimation accuracy is demonstrated for both a three-phase test circuit with typical secondary circuit topologies and single-phase secondary circuits in a real mixed-phase test system.« less

Distribution system model calibration with big data from AMI and PV inverters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peppanen, Jouni; Reno, Matthew J.; Broderick, Robert J.

Efficient management and coordination of distributed energy resources with advanced automation schemes requires accurate distribution system modeling and monitoring. Big data from smart meters and photovoltaic (PV) micro-inverters can be leveraged to calibrate existing utility models. This paper presents computationally efficient distribution system parameter estimation algorithms to improve the accuracy of existing utility feeder radial secondary circuit model parameters. The method is demonstrated using a real utility feeder model with advanced metering infrastructure (AMI) and PV micro-inverters, along with alternative parameter estimation approaches that can be used to improve secondary circuit models when limited measurement data is available. Lastly, themore » parameter estimation accuracy is demonstrated for both a three-phase test circuit with typical secondary circuit topologies and single-phase secondary circuits in a real mixed-phase test system.« less

Computer aided design of monolithic microwave and millimeter wave integrated circuits and subsystems

NASA Astrophysics Data System (ADS)

Ku, Walter H.

1989-05-01

The objectives of this research are to develop analytical and computer aided design techniques for monolithic microwave and millimeter wave integrated circuits (MMIC and MIMIC) and subsystems and to design and fabricate those ICs. Emphasis was placed on heterojunction-based devices, especially the High Electron Mobility Transition (HEMT), for both low noise and medium power microwave and millimeter wave applications. Circuits to be considered include monolithic low noise amplifiers, power amplifiers, and distributed and feedback amplifiers. Interactive computer aided design programs were developed, which include large signal models of InP MISFETs and InGaAs HEMTs. Further, a new unconstrained optimization algorithm POSM was developed and implemented in the general Analysis and Design program for Integrated Circuit (ADIC) for assistance in the design of largesignal nonlinear circuits.

Circuit Design Optimization Using Genetic Algorithm with Parameterized Uniform Crossover

NASA Astrophysics Data System (ADS)

Bao, Zhiguo; Watanabe, Takahiro

Evolvable hardware (EHW) is a new research field about the use of Evolutionary Algorithms (EAs) to construct electronic systems. EHW refers in a narrow sense to use evolutionary mechanisms as the algorithmic drivers for system design, while in a general sense to the capability of the hardware system to develop and to improve itself. Genetic Algorithm (GA) is one of typical EAs. We propose optimal circuit design by using GA with parameterized uniform crossover (GApuc) and with fitness function composed of circuit complexity, power, and signal delay. Parameterized uniform crossover is much more likely to distribute its disruptive trials in an unbiased manner over larger portions of the space, then it has more exploratory power than one and two-point crossover, so we have more chances of finding better solutions. Its effectiveness is shown by experiments. From the results, we can see that the best elite fitness, the average value of fitness of the correct circuits and the number of the correct circuits of GApuc are better than that of GA with one-point crossover or two-point crossover. The best case of optimal circuits generated by GApuc is 10.18% and 6.08% better in evaluating value than that by GA with one-point crossover and two-point crossover, respectively.

GATING CIRCUITS

DOEpatents

Merrill, L.C.

1958-10-14

Control circuits for vacuum tubes are described, and a binary counter having an improved trigger circuit is reported. The salient feature of the binary counter is the application of the input signal to the cathode of each of two vacuum tubes through separate capacitors and the connection of each cathode to ground through separate diodes. The control of the binary counter is achieved in this manner without special pulse shaping of the input signal. A further advantage of the circuit is the simplicity and minimum nuruber of components required, making its use particularly desirable in computer machines.

Flexible Circuits

NASA Technical Reports Server (NTRS)

1986-01-01

Adflex Solutions, Inc.'s flexible circuits may be molded to the shape of a chassis for bulk reduction. Particularly valuable when circuitry must be moved. They are produced by combining a plastic film, a metallic conductor and an adhesive. One adhesive, LARC-TPI, developed by the Langley Research Center, is a thermoplastic polyimide resin used to produce laminates by Rogers Corporation. It can be processed at a lower temperature, has good moisture resistance and excellent adherence. It is used to bond film to copper foil conductor materials in flexible circuits. The circuits have both aerospace and commercial applications.

Piezoelectric drive circuit

DOEpatents

Treu, C.A. Jr.

1999-08-31

A piezoelectric motor drive circuit is provided which utilizes the piezoelectric elements as oscillators and a Meacham half-bridge approach to develop feedback from the motor ground circuit to produce a signal to drive amplifiers to power the motor. The circuit automatically compensates for shifts in harmonic frequency of the piezoelectric elements due to pressure and temperature changes. 7 figs.

Targeting circuits

PubMed Central

Rajasethupathy, Priyamvada; Ferenczi, Emily; Deisseroth, Karl

2017-01-01

Current optogenetic methodology enables precise inhibition or excitation of neural circuits, spanning timescales as needed from the acute (milliseconds) to the chronic (many days or more), for experimental modulation of network activity and animal behavior. Such broad temporal versatility, unique to optogenetic control, is particularly powerful when combined with brain activity measurements that span both acute and chronic timescales as well. This enables, for instance, the study of adaptive circuit dynamics across the intact brain, and tuning interventions to match activity patterns naturally observed during behavior in the same individual. Although the impact of this approach has been greater on basic research than on clinical translation, it is natural to ask if specific neural circuit activity patterns discovered to be involved in controlling adaptive or maladaptive behaviors could become targets for treatment of neuropsychiatric diseases. Here we consider the landscape of such ideas related to therapeutic targeting of circuit dynamics, taking note of developments not only in optical but also in ultrasonic, magnetic, and thermal methods. We note the recent emergence of first-in-kind optogenetically-guided clinical outcomes, as well as opportunities related to the integration of interventions and readouts spanning diverse circuit-physiology, molecular, and behavioral modalities. PMID:27104976

Decoding Grasping Movements from the Parieto-Frontal Reaching Circuit in the Nonhuman Primate.

PubMed

Nelissen, Koen; Fiave, Prosper Agbesi; Vanduffel, Wim

2018-04-01

Prehension movements typically include a reaching phase, guiding the hand toward the object, and a grip phase, shaping the hand around it. The dominant view posits that these components rely upon largely independent parieto-frontal circuits: a dorso-medial circuit involved in reaching and a dorso-lateral circuit involved in grasping. However, mounting evidence suggests a more complex arrangement, with dorso-medial areas contributing to both reaching and grasping. To investigate the role of the dorso-medial reaching circuit in grasping, we trained monkeys to reach-and-grasp different objects in the dark and determined if hand configurations could be decoded from functional magnetic resonance imaging (MRI) responses obtained from the reaching and grasping circuits. Indicative of their established role in grasping, object-specific grasp decoding was found in anterior intraparietal (AIP) area, inferior parietal lobule area PFG and ventral premotor region F5 of the lateral grasping circuit, and primary motor cortex. Importantly, the medial reaching circuit also conveyed robust grasp-specific information, as evidenced by significant decoding in parietal reach regions (particular V6A) and dorsal premotor region F2. These data support the proposed role of dorso-medial "reach" regions in controlling aspects of grasping and demonstrate the value of complementing univariate with more sensitive multivariate analyses of functional MRI (fMRI) data in uncovering information coding in the brain.

PARALYZER FOR PULSE HEIGHT DISTRIBUTION ANALYZER

DOEpatents

Fairstein, E.

1960-01-19

A paralyzer circuit is described for use with a pulseheight distribution analyzer to prevent the analyzer from counting overlapping pulses where they would serve to provide a false indication. The paralyzer circuit comprises a pair of cathode-coupled amplifiers for amplifying pulses of opposite polarity. Diodes are provided having their anodes coupled to the separate outputs of the amplifiers to produce only positive signals, and a trigger circuit is coupled to the diodes ior operation by input pulses of either polarity from the amplifiers. A delay network couples the output of the trigger circuit for delaying the pulses.

Analysis and synthesis of distributed-lumped-active networks by digital computer

NASA Technical Reports Server (NTRS)

1973-01-01

The use of digital computational techniques in the analysis and synthesis of DLA (distributed lumped active) networks is considered. This class of networks consists of three distinct types of elements, namely, distributed elements (modeled by partial differential equations), lumped elements (modeled by algebraic relations and ordinary differential equations), and active elements (modeled by algebraic relations). Such a characterization is applicable to a broad class of circuits, especially including those usually referred to as linear integrated circuits, since the fabrication techniques for such circuits readily produce elements which may be modeled as distributed, as well as the more conventional lumped and active ones.

A hybrid analytical model for open-circuit field calculation of multilayer interior permanent magnet machines

NASA Astrophysics Data System (ADS)

Zhang, Zhen; Xia, Changliang; Yan, Yan; Geng, Qiang; Shi, Tingna

2017-08-01

Due to the complicated rotor structure and nonlinear saturation of rotor bridges, it is difficult to build a fast and accurate analytical field calculation model for multilayer interior permanent magnet (IPM) machines. In this paper, a hybrid analytical model suitable for the open-circuit field calculation of multilayer IPM machines is proposed by coupling the magnetic equivalent circuit (MEC) method and the subdomain technique. In the proposed analytical model, the rotor magnetic field is calculated by the MEC method based on the Kirchhoff's law, while the field in the stator slot, slot opening and air-gap is calculated by subdomain technique based on the Maxwell's equation. To solve the whole field distribution of the multilayer IPM machines, the coupled boundary conditions on the rotor surface are deduced for the coupling of the rotor MEC and the analytical field distribution of the stator slot, slot opening and air-gap. The hybrid analytical model can be used to calculate the open-circuit air-gap field distribution, back electromotive force (EMF) and cogging torque of multilayer IPM machines. Compared with finite element analysis (FEA), it has the advantages of faster modeling, less computation source occupying and shorter time consuming, and meanwhile achieves the approximate accuracy. The analytical model is helpful and applicable for the open-circuit field calculation of multilayer IPM machines with any size and pole/slot number combination.

Two-dimensional thermal modeling of power monolithic microwave integrated circuits (MMIC's)

NASA Technical Reports Server (NTRS)

Fan, Mark S.; Christou, Aris; Pecht, Michael G.

1992-01-01

Numerical simulations of the two-dimensional temperature distributions for a typical GaAs MMIC circuit are conducted, aiming at understanding the heat conduction process of the circuit chip and providing temperature information for device reliability analysis. The method used is to solve the two-dimensional heat conduction equation with a control-volume-based finite difference scheme. In particular, the effects of the power dissipation and the ambient temperature are examined, and the criterion for the worst operating environment is discussed in terms of the allowed highest device junction temperature.

Mapping Inhibitory Neuronal Circuits by Laser Scanning Photostimulation

PubMed Central

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

2011-01-01

Inhibitory neurons are crucial to cortical function. They comprise about 20% of the entire cortical neuronal population and can be further subdivided into diverse subtypes based on their immunochemical, morphological, and physiological properties1-4. Although previous research has revealed much about intrinsic properties of individual types of inhibitory neurons, knowledge about their local circuit connections is still relatively limited3,5,6. Given that each individual neuron's function is shaped by its excitatory and inhibitory synaptic input within cortical circuits, we have been using laser scanning photostimulation (LSPS) to map local circuit connections to specific inhibitory cell types. Compared to conventional electrical stimulation or glutamate puff stimulation, LSPS has unique advantages allowing for extensive mapping and quantitative analysis of local functional inputs to individually recorded neurons3,7-9. Laser photostimulation via glutamate uncaging selectively activates neurons perisomatically, without activating axons of passage or distal dendrites, which ensures a sub-laminar mapping resolution. The sensitivity and efficiency of LSPS for mapping inputs from many stimulation sites over a large region are well suited for cortical circuit analysis. Here we introduce the technique of LSPS combined with whole-cell patch clamping for local inhibitory circuit mapping. Targeted recordings of specific inhibitory cell types are facilitated by use of transgenic mice expressing green fluorescent proteins (GFP) in limited inhibitory neuron populations in the cortex3,10, which enables consistent sampling of the targeted cell types and unambiguous identification of the cell types recorded. As for LSPS mapping, we outline the system instrumentation, describe the experimental procedure and data acquisition, and present examples of circuit mapping in mouse primary somatosensory cortex. As illustrated in our experiments, caged glutamate is activated in a spatially

[Shunt and short circuit].

PubMed

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.

Fault-tolerant power distribution system

NASA Technical Reports Server (NTRS)

Volp, Jeffrey A. (Inventor)

1987-01-01

A fault-tolerant power distribution system which includes a plurality of power sources and a plurality of nodes responsive thereto for supplying power to one or more loads associated with each node. Each node includes a plurality of switching circuits, each of which preferably uses a power field effect transistor which provides a diode operation when power is first applied to the nodes and which thereafter provides bi-directional current flow through the switching circuit in a manner such that a low voltage drop is produced in each direction. Each switching circuit includes circuitry for disabling the power field effect transistor when the current in the switching circuit exceeds a preselected value.

Automatic recloser circuit breaker integrated with GSM technology for power system notification

NASA Astrophysics Data System (ADS)

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.

Macromodels of digital integrated circuits for program packages of circuit engineering design

NASA Astrophysics Data System (ADS)

Petrenko, A. I.; Sliusar, P. B.; Timchenko, A. P.

1984-04-01

Various aspects of the generation of macromodels of digital integrated circuits are examined, and their effective application in program packages of circuit engineering design is considered. Three levels of macromodels are identified, and the application of such models to the simulation of circuit outputs is discussed.

49 CFR 236.5 - Design of control circuits on closed circuit principle.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 4 2014-10-01 2014-10-01 false Design of control circuits on closed circuit... THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems General § 236.5 Design of control circuits on...

49 CFR 236.5 - Design of control circuits on closed circuit principle.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Design of control circuits on closed circuit... THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems General § 236.5 Design of control circuits on...

49 CFR 236.5 - Design of control circuits on closed circuit principle.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 4 2012-10-01 2012-10-01 false Design of control circuits on closed circuit... THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems General § 236.5 Design of control circuits on...

49 CFR 236.5 - Design of control circuits on closed circuit principle.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Design of control circuits on closed circuit... THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems General § 236.5 Design of control circuits on...

49 CFR 236.5 - Design of control circuits on closed circuit principle.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 4 2013-10-01 2013-10-01 false Design of control circuits on closed circuit... THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems General § 236.5 Design of control circuits on...

Supply and distribution of primary healthcare registered nurses in british columbia.

PubMed

Wong, Sabrina T; Watson, Diane E; Young, Ella; Mooney, Dawn

2009-11-01

WHAT DID WE DO?: This study uses an existing data source to (a) describe the population and geographic distribution of registered nurses (RNs) working in primary healthcare (PHC) in British Columbia, (b) compare this workforce to PHC physicians and (c) assess the distribution of PHC-RNs relative to population health status. WHAT DID WE LEARN?: Of the 27,570 practising RNs in British Columbia in 2000, there were 3,179 (12%) in the PHC workforce. This translates into 147 people per practising RN and 1,277 people per PHC-RN. In 2000, there were 990 people per PHC physician. PHC-RNs represented 43% of the combined PHC workforce of physicians and RNs. A large proportion (47%) of PHC-RNs worked in community health centres, whereas less than 2% worked in physicians' offices. Geographic distribution of PHC-RNs is similar to the distribution of PHC physicians and is not associated with population health status. WHAT ARE THE IMPLICATIONS?: There seem to be sufficient PHC-RNs to implement policy objectives in support of interdisciplinary PHC teams, but physicians and nurses will increasingly need to practice in the same location or have access to electronic information systems to support coordination, continuity and comprehensiveness of PHC. The PHC workforce could be better deployed to align with population health status.

MULTIPLIER CIRCUIT

DOEpatents

Thomas, R.E.

1959-01-20

An electronic circuit is presented for automatically computing the product of two selected variables by multiplying the voltage pulses proportional to the variables. The multiplier circuit has a plurality of parallel resistors of predetermined values connected through separate gate circults between a first input and the output terminal. One voltage pulse is applied to thc flrst input while the second voltage pulse is applied to control circuitry for the respective gate circuits. Thc magnitude of the second voltage pulse selects the resistors upon which the first voltage pulse is imprcssed, whereby the resultant output voltage is proportional to the product of the input voltage pulses

Digital circuits using universal logic gates

NASA Technical Reports Server (NTRS)

Whitaker, Sterling R. (Inventor); Miles, Lowell H. (Inventor); Cameron, Eric G. (Inventor); Donohoe, Gregory W. (Inventor); Gambles, Jody W. (Inventor)

2004-01-01

According to the invention, a digital circuit design embodied in at least one of a structural netlist, a behavioral netlist, a hardware description language netlist, a full-custom ASIC, a semi-custom ASIC, an IP core, an integrated circuit, a hybrid of chips, one or more masks, a FPGA, and a circuit card assembly is disclosed. The digital circuit design includes first and second sub-circuits. The first sub-circuits comprise a first percentage of the digital circuit design and the second sub-circuits comprise a second percentage of the digital circuit design. Each of the second sub-circuits is substantially comprised of one or more kernel circuits. The kernel circuits are comprised of selection circuits. The second percentage is at least 5%. In various embodiments, the second percentage could be at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 95%.

Remote reset circuit

DOEpatents

Gritzo, Russell E.

1987-01-01

A remote reset circuit acts as a stand-alone monitor and controller by clocking in each character sent by a terminal to a computer and comparing it to a given reference character. When a match occurs, the remote reset circuit activates the system's hardware reset line. The remote reset circuit is hardware based centered around monostable multivibrators and is unaffected by system crashes, partial serial transmissions, or power supply transients.

Optimization study on inductive-resistive circuit for broadband piezoelectric energy harvesters

NASA Astrophysics Data System (ADS)

Tan, Ting; Yan, Zhimiao

2017-03-01

The performance of cantilever-beam piezoelectric energy harvester is usually analyzed with pure resistive circuit. The optimal performance of such a vibration-based energy harvesting system is limited by narrow bandwidth around its modified natural frequency. For broadband piezoelectric energy harvesting, series and parallel inductive-resistive circuits are introduced. The electromechanical coupled distributed parameter models for such systems under harmonic base excitations are decoupled with modified natural frequency and electrical damping to consider the coupling effect. Analytical solutions of the harvested power and tip displacement for the electromechanical decoupled model are confirmed with numerical solutions for the coupled model. The optimal performance of piezoelectric energy harvesting with inductive-resistive circuits is revealed theoretically as constant maximal power at any excitation frequency. This is achieved by the scenarios of matching the modified natural frequency with the excitation frequency and equating the electrical damping to the mechanical damping. The inductance and load resistance should be simultaneously tuned to their optimal values, which may not be applicable for very high electromechanical coupling systems when the excitation frequency is higher than their natural frequencies. With identical optimal performance, the series inductive-resistive circuit is recommended for relatively small load resistance, while the parallel inductive-resistive circuit is suggested for relatively large load resistance. This study provides a simplified optimization method for broadband piezoelectric energy harvesters with inductive-resistive circuits.

Sensor readout detector circuit

DOEpatents

Chu, Dahlon D.; Thelen, Jr., Donald C.

1998-01-01

A sensor readout detector circuit is disclosed that is capable of detecting sensor signals down to a few nanoamperes or less in a high (microampere) background noise level. The circuit operates at a very low standby power level and is triggerable by a sensor event signal that is above a predetermined threshold level. A plurality of sensor readout detector circuits can be formed on a substrate as an integrated circuit (IC). These circuits can operate to process data from an array of sensors in parallel, with only data from active sensors being processed for digitization and analysis. This allows the IC to operate at a low power level with a high data throughput for the active sensors. The circuit may be used with many different types of sensors, including photodetectors, capacitance sensors, chemically-sensitive sensors or combinations thereof to provide a capability for recording transient events or for recording data for a predetermined period of time following an event trigger. The sensor readout detector circuit has applications for portable or satellite-based sensor systems.

Sensor readout detector circuit

DOEpatents

Chu, D.D.; Thelen, D.C. Jr.

1998-08-11

A sensor readout detector circuit is disclosed that is capable of detecting sensor signals down to a few nanoamperes or less in a high (microampere) background noise level. The circuit operates at a very low standby power level and is triggerable by a sensor event signal that is above a predetermined threshold level. A plurality of sensor readout detector circuits can be formed on a substrate as an integrated circuit (IC). These circuits can operate to process data from an array of sensors in parallel, with only data from active sensors being processed for digitization and analysis. This allows the IC to operate at a low power level with a high data throughput for the active sensors. The circuit may be used with many different types of sensors, including photodetectors, capacitance sensors, chemically-sensitive sensors or combinations thereof to provide a capability for recording transient events or for recording data for a predetermined period of time following an event trigger. The sensor readout detector circuit has applications for portable or satellite-based sensor systems. 6 figs.

Comparison of modified driver circuit and capacitor-transfer circuit in longitudinally excited N2 laser.

PubMed

Uno, Kazuyuki; Akitsu, Tetsuya; Nakamura, Kenshi; Jitsuno, Takahisa

2013-04-01

We developed a modified driver circuit composed of a capacitance and a spark gap, called a direct-drive circuit, for a longitudinally excited gas laser. The direct-drive circuit uses a large discharge impedance caused by a long discharge length of the longitudinal excitation scheme and eliminates the buffer capacitance used in the traditional capacitor-transfer circuit. We compared the direct-drive circuit and the capacitor-transfer circuit in a longitudinally excited N2 laser (wavelength: 337 nm). Producing high output energy with the capacitor-transfer circuit requires a large storage capacitance and a discharge tube with optimum dimensions (an inner diameter of 4 mm and a length of 10 cm in this work); in contrast, the direct-drive circuit requires a high breakdown voltage, achieved with a small storage capacitance and a large discharge tube. Additionally, for the same input energy of 792 mJ, the maximum output energy of the capacitor-transfer circuit was 174.2 μJ, and that of the direct-drive circuit was 344.7 μJ.

A Flipped First-Year Digital Circuits Course for Engineering and Technology Students

ERIC Educational Resources Information Center

Yelamarthi, Kumar; Drake, Eron

2015-01-01

This paper describes a flipped and improved first-year digital circuits (DC) course that incorporates several active learning strategies. With the primary objective of increasing student interest and learning, an integrated instructional design framework is proposed to provide first-year engineering and technology students with practical knowledge…

Separating OR, SUM, and XOR Circuits.

PubMed

Find, Magnus; Göös, Mika; Järvisalo, Matti; Kaski, Petteri; Koivisto, Mikko; Korhonen, Janne H

2016-08-01

Given a boolean n × n matrix A we consider arithmetic circuits for computing the transformation x ↦ Ax over different semirings. Namely, we study three circuit models: monotone OR-circuits, monotone SUM-circuits (addition of non-negative integers), and non-monotone XOR-circuits (addition modulo 2). Our focus is on separating OR-circuits from the two other models in terms of circuit complexity: We show how to obtain matrices that admit OR-circuits of size O ( n ), but require SUM-circuits of size Ω( n 3/2 /log 2 n ).We consider the task of rewriting a given OR-circuit as a XOR-circuit and prove that any subquadratic-time algorithm for this task violates the strong exponential time hypothesis.

CIRCUITS FOR CURRENT MEASUREMENTS

DOEpatents

Cox, R.J.

1958-11-01

Circuits are presented for measurement of a logarithmic scale of current flowing in a high impedance. In one form of the invention the disclosed circuit is in combination with an ionization chamber to measure lonization current. The particular circuit arrangement lncludes a vacuum tube having at least one grid, an ionization chamber connected in series with a high voltage source and the grid of the vacuum tube, and a d-c amplifier feedback circuit. As the ionization chamber current passes between the grid and cathode of the tube, the feedback circuit acts to stabilize the anode current, and the feedback voltage is a measure of the logaritbm of the ionization current.

Method of determining the open circuit voltage of a battery in a closed circuit

DOEpatents

Brown, William E.

1980-01-01

The open circuit voltage of a battery which is connected in a closed circuit is determined without breaking the circuit or causing voltage upsets therein. The closed circuit voltage across the battery and the current flowing through it are determined under normal load and then a fractional change is made in the load and the new current and voltage values determined. The open circuit voltage is then calculated, according to known principles, from the two sets of values.

The Drosophila Circadian Pacemaker Circuit: Pas de Deux or Tarantella?

PubMed Central

Sheeba, Vasu; Kaneko, Maki; Sharma, Vijay Kumar; Holmes, Todd C.

2008-01-01

Molecular genetic analysis of the fruit fly Drosophila melanogaster has revolutionized our understanding of the transcription/translation loop mechanisms underlying the circadian molecular oscillator. More recently, Drosophila has been used to understand how different neuronal groups within the circadian pacemaker circuit interact to regulate the overall behavior of the fly in response to daily cyclic environmental cues as well as seasonal changes. Our present understanding of circadian timekeeping at the molecular and circuit level is discussed with a critical evaluation of the strengths and weaknesses of present models. Two models for circadian neural circuits are compared: one that posits that two anatomically distinct oscillators control the synchronization to the two major daily morning and evening transitions, versus a distributed network model that posits that many cell-autonomous oscillators are coordinated in a complex fashion and respond via plastic mechanisms to changes in environmental cues. PMID:18307108

Selective Manipulation of Neural Circuits.

PubMed

Park, Hong Geun; Carmel, Jason B

2016-04-01

Unraveling the complex network of neural circuits that form the nervous system demands tools that can manipulate specific circuits. The recent evolution of genetic tools to target neural circuits allows an unprecedented precision in elucidating their function. Here we describe two general approaches for achieving circuit specificity. The first uses the genetic identity of a cell, such as a transcription factor unique to a circuit, to drive expression of a molecule that can manipulate cell function. The second uses the spatial connectivity of a circuit to achieve specificity: one genetic element is introduced at the origin of a circuit and the other at its termination. When the two genetic elements combine within a neuron, they can alter its function. These two general approaches can be combined to allow manipulation of neurons with a specific genetic identity by introducing a regulatory gene into the origin or termination of the circuit. We consider the advantages and disadvantages of both these general approaches with regard to specificity and efficacy of the manipulations. We also review the genetic techniques that allow gain- and loss-of-function within specific neural circuits. These approaches introduce light-sensitive channels (optogenetic) or drug sensitive channels (chemogenetic) into neurons that form specific circuits. We compare these tools with others developed for circuit-specific manipulation and describe the advantages of each. Finally, we discuss how these tools might be applied for identification of the neural circuits that mediate behavior and for repair of neural connections.

Remote reset circuit

DOEpatents

Gritzo, R.E.

1985-09-12

A remote reset circuit acts as a stand-along monitor and controller by clocking in each character sent by a terminal to a computer and comparing it to a given reference character. When a match occurs, the remote reset circuit activates the system's hardware reset line. The remote reset circuit is hardware based centered around monostable multivibrators and is unaffected by system crashes, partial serial transmissions, or power supply transients. 4 figs.

A Circuit to Demonstrate Phase Relationships in "RLC" Circuits

ERIC Educational Resources Information Center

Sokol, P. E.; Warren, G.; Zheng, B.; Smith, P.

2013-01-01

We have developed a circuit to demonstrate the phase relationships between resistive and reactive elements in series "RLC" circuits. We utilize a differential amplifier to allow the phases of the three elements and the current to be simultaneously displayed on an inexpensive four channel oscilloscope. We have included a novel circuit…

Polymorphic Electronic Circuits

NASA Technical Reports Server (NTRS)

Stoica, Adrian

2004-01-01

Polymorphic electronics is a nascent technological discipline that involves, among other things, designing the same circuit to perform different analog and/or digital functions under different conditions. For example, a circuit can be designed to function as an OR gate or an AND gate, depending on the temperature (see figure). Polymorphic electronics can also be considered a subset of polytronics, which is a broader technological discipline in which optical and possibly other information- processing systems could also be designed to perform multiple functions. Polytronics is an outgrowth of evolvable hardware (EHW). The basic concepts and some specific implementations of EHW were described in a number of previous NASA Tech Briefs articles. To recapitulate: The essence of EHW is to design, construct, and test a sequence of populations of circuits that function as incrementally better solutions of a given design problem through the selective, repetitive connection and/or disconnection of capacitors, transistors, amplifiers, inverters, and/or other circuit building blocks. The evolution is guided by a search-and-optimization algorithm (in particular, a genetic algorithm) that operates in the space of possible circuits to find a circuit that exhibits an acceptably close approximation of the desired functionality. The evolved circuits can be tested by computational simulation (in which case the evolution is said to be extrinsic), tested in real hardware (in which case the evolution is said to be intrinsic), or tested in random sequences of computational simulation and real hardware (in which case the evolution is said to be mixtrinsic).

Visualizing Metal Content and Intracellular Distribution in Primary Hippocampal Neurons with Synchrotron X-Ray Fluorescence

PubMed Central

2016-01-01

Increasing evidence suggests that metal dyshomeostasis plays an important role in human neurodegenerative diseases. Although distinctive metal distributions are described for mature hippocampus and cortex, much less is known about metal levels and intracellular distribution in individual hippocampal neuronal somata. To solve this problem, we conducted quantitative metal analyses utilizing synchrotron radiation X-Ray fluorescence on frozen hydrated primary cultured neurons derived from rat embryonic cortex (CTX) and two regions of the hippocampus: dentate gyrus (DG) and CA1. Comparing average metal contents showed that the most abundant metals were calcium, iron, and zinc, whereas metals such as copper and manganese were less than 10% of zinc. Average metal contents were generally similar when compared across neurons cultured from CTX, DG, and CA1, except for manganese that was larger in CA1. However, each metal showed a characteristic spatial distribution in individual neuronal somata. Zinc was uniformly distributed throughout the cytosol, with no evidence for the existence of previously identified zinc-enriched organelles, zincosomes. Calcium showed a peri-nuclear distribution consistent with accumulation in endoplasmic reticulum and/or mitochondria. Iron showed 2–3 distinct highly concentrated puncta only in peri-nuclear locations. Notwithstanding the small sample size, these analyses demonstrate that primary cultured neurons show characteristic metal signatures. The iron puncta probably represent iron-accumulating organelles, siderosomes. Thus, the metal distributions observed in mature brain structures are likely the result of both intrinsic neuronal factors that control cellular metal content and extrinsic factors related to the synaptic organization, function, and contacts formed and maintained in each region. PMID:27434052

Method and Circuit for Injecting a Precise Amount of Charge onto a Circuit Node

NASA Technical Reports Server (NTRS)

Hancock, Bruce R. (Inventor)

2016-01-01

A method and circuit for injecting charge into a circuit node, comprising (a) resetting a capacitor's voltage through a first transistor; (b) after the resetting, pre-charging the capacitor through the first transistor; and (c) after the pre-charging, further charging the capacitor through a second transistor, wherein the second transistor is connected between the capacitor and a circuit node, and the further charging draws charge through the second transistor from the circuit node, thereby injecting charge into the circuit node.

Highly Uniform Carbon Nanotube Field-Effect Transistors and Medium Scale Integrated Circuits.

PubMed

Chen, Bingyan; Zhang, Panpan; Ding, Li; Han, Jie; Qiu, Song; Li, Qingwen; Zhang, Zhiyong; Peng, Lian-Mao

2016-08-10

Top-gated p-type field-effect transistors (FETs) have been fabricated in batch based on carbon nanotube (CNT) network thin films prepared from CNT solution and present high yield and highly uniform performance with small threshold voltage distribution with standard deviation of 34 mV. According to the property of FETs, various logical and arithmetical gates, shifters, and d-latch circuits were designed and demonstrated with rail-to-rail output. In particular, a 4-bit adder consisting of 140 p-type CNT FETs was demonstrated with higher packing density and lower supply voltage than other published integrated circuits based on CNT films, which indicates that CNT based integrated circuits can reach to medium scale. In addition, a 2-bit multiplier has been realized for the first time. Benefitted from the high uniformity and suitable threshold voltage of CNT FETs, all of the fabricated circuits based on CNT FETs can be driven by a single voltage as small as 2 V.

A novel surrogate-based approach for optimal design of electromagnetic-based circuits

NASA Astrophysics Data System (ADS)

Hassan, Abdel-Karim S. O.; Mohamed, Ahmed S. A.; Rabie, Azza A.; Etman, Ahmed S.

2016-02-01

A new geometric design centring approach for optimal design of central processing unit-intensive electromagnetic (EM)-based circuits is introduced. The approach uses norms related to the probability distribution of the circuit parameters to find distances from a point to the feasible region boundaries by solving nonlinear optimization problems. Based on these normed distances, the design centring problem is formulated as a max-min optimization problem. A convergent iterative boundary search technique is exploited to find the normed distances. To alleviate the computation cost associated with the EM-based circuits design cycle, space-mapping (SM) surrogates are used to create a sequence of iteratively updated feasible region approximations. In each SM feasible region approximation, the centring process using normed distances is implemented, leading to a better centre point. The process is repeated until a final design centre is attained. Practical examples are given to show the effectiveness of the new design centring method for EM-based circuits.

Multi-Layer E-Textile Circuits

NASA Technical Reports Server (NTRS)

Dunne, Lucy E.; Bibeau, Kaila; Mulligan, Lucie; Frith, Ashton; Simon, Cory

2012-01-01

Stitched e-textile circuits facilitate wearable, flexible, comfortable wearable technology. However, while stitched methods of e-textile circuits are common, multi-layer circuit creation remains a challenge. Here, we present methods of stitched multi-layer circuit creation using accessible tools and techniques.

Experimental Performance of a Frequency Measurement Circuit.

DTIC Science & Technology

1984-12-01

STANDARDS 1963-A NAVAL POSTGRADUATE SCHOOL Monterey, California N O In DTISEL ECTE. APR 26 1985 THESIS EXPERIMENTAL PERFORMANCE OF A FREQUENCY MEASUREMENT...CIRCUIT by CO George H. Eastwood December 198𔃾 Thesis Advisor: G. A. Myers * Approved for public release; distribution is unlimited. * 85 4 2 105...ACCESSION NO. 3. RECIPIENT’S CATALOG NUMBER 4. TITLE (and Subtitle) S. TYPE OF REPORT & PERIOD COVERED Experimental Performance of a Master’s Thesis

Compact atmospheric pressure plasma self-resonant drive circuits

NASA Astrophysics Data System (ADS)

Law, V. J.; Anghel, S. D.

2012-02-01

This paper reports on compact solid-state self-resonant drive circuits that are specifically designed to drive an atmospheric pressure plasma jet and a parallel-plate dielectric barrier discharge of small volume (0.5 cm3). The atmospheric pressure plasma (APP) device can be operated with helium, argon or a mixture of both. Equivalent electrical models of the self-resonant drive circuits and discharge are developed and used to estimate the plasma impedance, plasma power density, current density or electron number density of three APP devices. These parameters and the kinetic gas temperature are dependent on the self-resonant frequency of the APP device. For a fixed switching frequency and APP device geometry, the plasma parameters are controlled by adjusting the dc voltage at the primary coil and the gas flow rate. The resonant frequency is controlled by the selection of the switching power transistor and means of step-up voltage transformation (ferrite core, flyback transformer, or Tesla coil). The flyback transformer operates in the tens of kHz, the ferrite core in the hundreds of kHz and Tesla coil in the MHz range. Embedded within this work is the principle of frequency pulling which is exemplified in the flyback transformer circuit that utilizes a pickup coil for feedback control of the switching frequency.

Automatic circuit interrupter

NASA Technical Reports Server (NTRS)

Dwinell, W. S.

1979-01-01

In technique, voice circuits connecting crew's cabin to launch station through umbilical connector disconnect automatically unused, or deadened portion of circuits immediately after vehicle is launched, eliminating possibility that unused wiring interferes with voice communications inside vehicle or need for manual cutoff switch and its associated wiring. Technique is applied to other types of electrical actuation circuits, also launch of mapped vehicles, such as balloons, submarines, test sleds, and test chambers-all requiring assistance of ground crew.

Superior model for fault tolerance computation in designing nano-sized circuit systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, N. S. S., E-mail: narinderjit@petronas.com.my; Muthuvalu, M. S., E-mail: msmuthuvalu@gmail.com; Asirvadam, V. S., E-mail: vijanth-sagayan@petronas.com.my

2014-10-24

As CMOS technology scales nano-metrically, reliability turns out to be a decisive subject in the design methodology of nano-sized circuit systems. As a result, several computational approaches have been developed to compute and evaluate reliability of desired nano-electronic circuits. The process of computing reliability becomes very troublesome and time consuming as the computational complexity build ups with the desired circuit size. Therefore, being able to measure reliability instantly and superiorly is fast becoming necessary in designing modern logic integrated circuits. For this purpose, the paper firstly looks into the development of an automated reliability evaluation tool based on the generalizationmore » of Probabilistic Gate Model (PGM) and Boolean Difference-based Error Calculator (BDEC) models. The Matlab-based tool allows users to significantly speed-up the task of reliability analysis for very large number of nano-electronic circuits. Secondly, by using the developed automated tool, the paper explores into a comparative study involving reliability computation and evaluation by PGM and, BDEC models for different implementations of same functionality circuits. Based on the reliability analysis, BDEC gives exact and transparent reliability measures, but as the complexity of the same functionality circuits with respect to gate error increases, reliability measure by BDEC tends to be lower than the reliability measure by PGM. The lesser reliability measure by BDEC is well explained in this paper using distribution of different signal input patterns overtime for same functionality circuits. Simulation results conclude that the reliability measure by BDEC depends not only on faulty gates but it also depends on circuit topology, probability of input signals being one or zero and also probability of error on signal lines.« less

Gustatory and reward brain circuits in the control of food intake

PubMed Central

Oliveira-Maia, Albino J.; Roberts, Craig D.; Simon, Sidney A.; Nicolelis, Miguel A.L.

2012-01-01

Gustation is a multisensory process allowing for the selection of nutrients and the rejection of irritating and/or toxic compounds. Since obesity is a highly prevalent condition that is critically dependent on food intake and energy expenditure, a deeper understanding of gustatory processing is an important objective in biomedical research. Recent findings have provided evidence that central gustatory processes are distributed across several cortical and sub-cortical brain areas. Furthermore, these gustatory sensory circuits are closely related to the circuits that process reward. Here, we present an overview of the activation and connectivity between central gustatory and reward areas. Moreover, and given the limitations in number and effectiveness of treatments currently available for overweight patients, we discuss the possibility of modulating neuronal activity in these circuits as an alternative in the treatment of obesity. PMID:21197607

Exchange circuits for FASTBUS slaves

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bratskii, A.A.; Matseev, M.Y.; Rybakov, V.G.

1985-09-01

This paper describes general-purpose circuits for FASTBUS interfacing of the functional part of a slave device. The circuits contain buffered receivers and transmitters, addressrecognition and data-transfer logic, and the required control/status registers. The described circuits are implemented with series-K500 integrated circuits.

Distribution and utilization of curative primary healthcare services in Lahej, Yemen.

PubMed

Bawazir, A A; Bin Hawail, T S; Al-Sakkaf, K A Z; Basaleem, H O; Muhraz, A F; Al-Shehri, A M

2013-09-01

No evidence-based data exist on the availability, accessibility and utilization of healthcare services in Lahej Governorate, Yemen. The aim of this study was to assess the distribution and utilization of curative services in primary healthcare units and centres in Lahej. Cross-sectional study (clustering sample). This study was conducted in three of the 15 districts in Lahej between December 2009 and August 2010. Household members were interviewed using a questionnaire to determine sociodemographic characteristics and types of healthcare services available in the area. The distribution of health centres, health units and hospitals did not match the size of the populations or areas of the districts included in this study. Geographical accessibility was the main obstacle to utilization. Factors associated with the utilization of curative services were significantly related to the time required to reach the nearest facility, seeking curative services during illness and awareness of the availability of health facilities (P < 0.01). There is an urgent need to look critically and scientifically at the distribution of healthcare services in the region in order to ensure accessibility and quality of services. Copyright © 2013 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Standardization of Schwarz-Christoffel transformation for engineering design of semiconductor and hybrid integrated-circuit elements

NASA Astrophysics Data System (ADS)

Yashin, A. A.

1985-04-01

A semiconductor or hybrid structure into a calculable two-dimensional region mapped by the Schwarz-Christoffel transformation and a universal algorithm can be constructed on the basis of Maxwell's electro-magnetic-thermal similarity principle for engineering design of integrated-circuit elements. The design procedure involves conformal mapping of the original region into a polygon and then the latter into a rectangle with uniform field distribution, where conductances and capacitances are calculated, using tabulated standard mapping functions. Subsequent synthesis of a device requires inverse conformal mapping. Devices adaptable as integrated-circuit elements are high-resistance film resistors with periodic serration, distributed-resistance film attenuators with high transformation ratio, coplanar microstrip lines, bipolar transistors, directional couplers with distributed coupling to microstrip lines for microwave bulk devices, and quasirregular smooth matching transitions from asymmetric to coplanar microstrip lines.

Superconducting flux flow digital circuits

DOEpatents

Hietala, Vincent M.; Martens, Jon S.; Zipperian, Thomas E.

1995-01-01

A NOR/inverter logic gate circuit and a flip flop circuit implemented with superconducting flux flow transistors (SFFTs). Both circuits comprise two SFFTs with feedback lines. They have extremely low power dissipation, very high switching speeds, and the ability to interface between Josephson junction superconductor circuits and conventional microelectronics.

Digital MOS integrated circuits

NASA Astrophysics Data System (ADS)

Elmasry, M. I.

MOS in digital circuit design is considered along with aspects of digital VLSI, taking into account a comparison of MOSFET logic circuits, 1-micrometer MOSFET VLSI technology, a generalized guide for MOSFET miniaturization, processing technologies, novel circuit structures for VLSI, and questions of circuit and system design for VLSI. MOS memory cells and circuits are discussed, giving attention to a survey of high-density dynamic RAM cell concepts, one-device cells for dynamic random-access memories, variable resistance polysilicon for high density CMOS Ram, high performance MOS EPROMs using a stacked-gate cell, and the optimization of the latching pulse for dynamic flip-flop sensors. Programmable logic arrays are considered along with digital signal processors, microprocessors, static RAMs, and dynamic RAMs.

Multiple components of surround modulation in primary visual cortex: multiple neural circuits with multiple functions?

PubMed Central

Nurminen, Lauri; Angelucci, Alessandra

2014-01-01

The responses of neurons in primary visual cortex (V1) to stimulation of their receptive field (RF) are modulated by stimuli in the RF surround. This modulation is suppressive when the stimuli in the RF and surround are of similar orientation, but less suppressive or facilitatory when they are cross-oriented. Similarly, in human vision surround stimuli selectively suppress the perceived contrast of a central stimulus. Although the properties of surround modulation have been thoroughly characterized in many species, cortical areas and sensory modalities, its role in perception remains unknown. Here we argue that surround modulation in V1 consists of multiple components having different spatio-temporal and tuning properties, generated by different neural circuits and serving different visual functions. One component arises from LGN afferents, is fast, untuned for orientation, and spatially restricted to the surround region nearest to the RF (the near-surround); its function is to normalize V1 cell responses to local contrast. Intra-V1 horizontal connections contribute a slower, narrowly orientation-tuned component to near-surround modulation, whose function is to increase the coding efficiency of natural images in manner that leads to the extraction of object boundaries. The third component is generated by topdown feedback connections to V1, is fast, broadly orientation-tuned, and extends into the far-surround; its function is to enhance the salience of behaviorally relevant visual features. Far- and near-surround modulation, thus, act as parallel mechanisms: the former quickly detects and guides saccades/attention to salient visual scene locations, the latter segments object boundaries in the scene. PMID:25204770

The test of VLSI circuits

NASA Astrophysics Data System (ADS)

Baviere, Ph.

Tests which have proven effective for evaluating VLSI circuits for space applications are described. It is recommended that circuits be examined after each manfacturing step to gain fast feedback on inadequacies in the production system. Data from failure modes which occur during operational lifetimes of circuits also permit redefinition of the manufacturing and quality control process to eliminate the defects identified. Other tests include determination of the operational envelope of the circuits, examination of the circuit response to controlled inputs, and the performance and functional speeds of ROM and RAM memories. Finally, it is desirable that all new circuits be designed with testing in mind.

Flexible Simulation E-Learning Environment for Studying Digital Circuits and Possibilities for It Deployment as Semantic Web Service

ERIC Educational Resources Information Center

Radoyska, P.; Ivanova, T.; Spasova, N.

2011-01-01

In this article we present a partially realized project for building a distributed learning environment for studying digital circuits Test and Diagnostics at TU-Sofia. We describe the main requirements for this environment, substantiate the developer platform choice, and present our simulation and circuit parameter calculation tools.…

Basal Ganglia Circuits as Targets for Neuromodulation in Parkinson Disease.

PubMed

DeLong, Mahlon R; Wichmann, Thomas

2015-11-01

The revival of stereotactic surgery for Parkinson disease (PD) in the 1990s, with pallidotomy and then with high-frequency deep brain stimulation (DBS), has led to a renaissance in functional surgery for movement and other neuropsychiatric disorders. To examine the scientific foundations and rationale for the use of ablation and DBS for treatment of neurologic and psychiatric diseases, using PD as the primary example. A summary of the large body of relevant literature is presented on anatomy, physiology, pathophysiology, and functional surgery for PD and other basal ganglia disorders. The signs and symptoms of movement disorders appear to result largely from signature abnormalities in one of several parallel and largely segregated basal ganglia thalamocortical circuits (ie, the motor circuit). The available evidence suggests that the varied movement disorders resulting from dysfunction of this circuit result from propagated disruption of downstream network activity in the thalamus, cortex, and brainstem. Ablation and DBS act to free downstream networks to function more normally. The basal ganglia thalamocortical circuit may play a key role in the expression of disordered movement, and the basal ganglia-brainstem projections may play roles in akinesia and disturbances of gait. Efforts are under way to target circuit dysfunction in brain areas outside of the traditionally implicated basal ganglia thalamocortical system, in particular, the pedunculopontine nucleus, to address gait disorders that respond poorly to levodopa and conventional DBS targets. Deep brain stimulation is now the treatment of choice for many patients with advanced PD and other movement disorders. The success of DBS and other forms of neuromodulation for neuropsychiatric disorders is the result of the ability to modulate circuit activity in discrete functional domains within the basal ganglia circuitry with highly focused interventions, which spare uninvolved areas that are often disrupted with

PRECISION TIME-DELAY CIRCUIT

DOEpatents

Creveling, R.

1959-03-17

A tine-delay circuit which produces a delay time in d. The circuit a capacitor, an te back resistance, connected serially with the anode of the diode going to ground. At the start of the time delay a negative stepfunction is applied to the series circuit and initiates a half-cycle transient oscillatory voltage terminated by a transient oscillatory voltage of substantially higher frequency. The output of the delay circuit is taken at the junction of the inductor and diode where a sudden voltage rise appears after the initiation of the higher frequency transient oscillations.

Common-signal-induced synchronization in photonic integrated circuits and its application to secure key distribution.

PubMed

Sasaki, Takuma; Kakesu, Izumi; Mitsui, Yusuke; Rontani, Damien; Uchida, Atsushi; Sunada, Satoshi; Yoshimura, Kazuyuki; Inubushi, Masanobu

2017-10-16

We experimentally achieve common-signal-induced synchronization in two photonic integrated circuits with short external cavities driven by a constant-amplitude random-phase light. The degree of synchronization can be controlled by changing the optical feedback phase of the two photonic integrated circuits. The change in the optical feedback phase leads to a significant redistribution of the spectral energy of optical and RF spectra, which is a unique characteristic of PICs with the short external cavity. The matching of the RF and optical spectra is necessary to achieve synchronization between the two PICs, and stable synchronization can be obtained over an hour in the presence of optical feedback. We succeed in generating information-theoretic secure keys and achieving the final key generation rate of 184 kb/s using the PICs.

Photonic integrated circuits unveil crisis-induced intermittency.

PubMed

Karsaklian Dal Bosco, Andreas; Akizawa, Yasuhiro; Kanno, Kazutaka; Uchida, Atsushi; Harayama, Takahisa; Yoshimura, Kazuyuki

2016-09-19

We experimentally investigate an intermittent route to chaos in a photonic integrated circuit consisting of a semiconductor laser with time-delayed optical feedback from a short external cavity. The transition from a period-doubling dynamics to a fully-developed chaos reveals a stage intermittently exhibiting these two dynamics. We unveil the bifurcation mechanism underlying this route to chaos by using the Lang-Kobayashi model and demonstrate that the process is based on a phenomenon of attractor expansion initiated by a particular distribution of the local Lyapunov exponents. We emphasize on the crucial importance of the distribution of the steady-state solutions introduced by the time-delayed feedback on the existence of this intermittent dynamics.

Superconducting flux flow digital circuits

DOEpatents

Hietala, V.M.; Martens, J.S.; Zipperian, T.E.

1995-02-14

A NOR/inverter logic gate circuit and a flip flop circuit implemented with superconducting flux flow transistors (SFFTs) are disclosed. Both circuits comprise two SFFTs with feedback lines. They have extremely low power dissipation, very high switching speeds, and the ability to interface between Josephson junction superconductor circuits and conventional microelectronics. 8 figs.

Auto-programmable impulse neural circuits

NASA Technical Reports Server (NTRS)

Watula, D.; Meador, J.

1990-01-01

Impulse neural networks use pulse trains to communicate neuron activation levels. Impulse neural circuits emulate natural neurons at a more detailed level than that typically employed by contemporary neural network implementation methods. An impulse neural circuit which realizes short term memory dynamics is presented. The operation of that circuit is then characterized in terms of pulse frequency modulated signals. Both fixed and programmable synapse circuits for realizing long term memory are also described. The implementation of a simple and useful unsupervised learning law is then presented. The implementation of a differential Hebbian learning rule for a specific mean-frequency signal interpretation is shown to have a straightforward implementation using digital combinational logic with a variation of a previously developed programmable synapse circuit. This circuit is expected to be exploited for simple and straightforward implementation of future auto-adaptive neural circuits.

Visualizing Metal Content and Intracellular Distribution in Primary Hippocampal Neurons with Synchrotron X-Ray Fluorescence

DOE PAGES

Colvin, Robert A.; Jin, Qiaoling; Lai, Barry; ...

2016-07-19

Increasing evidence suggests that metal dyshomeostasis plays an important role in human neurodegenerative diseases. Although distinctive metal distributions are described for mature hippocampus and cortex, much less is known about metal levels and intracellular distribution in individual hippocampal neuronal somata. To solve this problem, we conducted quantitative metal analyses utilizing synchrotron radiation X-Ray fluorescence on frozen hydrated primary cultured neurons derived from rat embryonic cortex (CTX) and two regions of the hippocampus: dentate gyrus (DG) and CA1. Also, comparing average metal contents showed that the most abundant metals were calcium, iron, and zinc, whereas metals such as copper and manganesemore » were less than 10% of zinc. Average metal contents were generally similar when compared across neurons cultured from CTX, DG, and CA1, except for manganese that was larger in CA1. However, each metal showed a characteristic spatial distribution in individual neuronal somata. Zinc was uniformly distributed throughout the cytosol, with no evidence for the existence of previously identified zinc-enriched organelles, zincosomes. Calcium showed a peri-nuclear distribution consistent with accumulation in endoplasmic reticulum and/or mitochondria. Iron showed 2-3 distinct highly concentrated puncta only in peri-nuclear locations. Notwithstanding the small sample size, these analyses demonstrate that primary cultured neurons show characteristic metal signatures. The iron puncta probably represent iron-accumulating organelles, siderosomes. Thus, the metal distributions observed in mature brain structures are likely the result of both intrinsic neuronal factors that control cellular metal content and extrinsic factors related to the synaptic organization, function, and contacts formed and maintained in each region.« less

Electronic Circuit Analysis Language (ECAL)

NASA Astrophysics Data System (ADS)

Chenghang, C.

1983-03-01

The computer aided design technique is an important development in computer applications and it is an important component of computer science. The special language for electronic circuit analysis is the foundation of computer aided design or computer aided circuit analysis (abbreviated as CACD and CACA) of simulated circuits. Electronic circuit analysis language (ECAL) is a comparatively simple and easy to use circuit analysis special language which uses the FORTRAN language to carry out the explanatory executions. It is capable of conducting dc analysis, ac analysis, and transient analysis of a circuit. Futhermore, the results of the dc analysis can be used directly as the initial conditions for the ac and transient analyses.

Diode-quad bridge circuit means

NASA Technical Reports Server (NTRS)

Harrison, D. R.; Dimeff, J. (Inventor)

1975-01-01

Diode-quad bridge circuit means is described for use as a transducer circuit or as a discriminator circuit. It includes: (1) a diode bridge having first, second, third, and fourth bridge terminals consecutively coupled together by four diodes polarized in circulating relationship; (2) a first impedance connected between the second bridge terminal and a circuit ground; (3) a second impedance connected between the fourth bridge terminal and the circuit ground; (4) a signal source having a first source terminal capacitively coupled to the first and third bridge terminals, and a second source terminal connected to the circuit ground; and (5) an output terminal coupled to the first bridge terminal and at which an output signal may be taken.

Charge regulation circuit

DOEpatents

Ball, Don G.

1992-01-01

A charge regulation circuit provides regulation of an unregulated voltage supply in the range of 0.01%. The charge regulation circuit is utilized in a preferred embodiment in providing regulated voltage for controlling the operation of a laser.

An Electronics Course Emphasizing Circuit Design

ERIC Educational Resources Information Center

Bergeson, Haven E.

1975-01-01

Describes a one-quarter introductory electronics course in which the students use a variety of inexpensive integrated circuits to design and construct a large number of useful circuits. Presents the subject matter of the course in three parts: linear circuits, digital circuits, and more complex circuits. (GS)

Electrical Circuits and Water Analogies

ERIC Educational Resources Information Center

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)

Soldering Tool for Integrated Circuits

NASA Technical Reports Server (NTRS)

Takahashi, Ted H.

1987-01-01

Many connections soldered simultaneously in confined spaces. Improved soldering tool bonds integrated circuits onto printed-circuit boards. Intended especially for use with so-called "leadless-carrier" integrated circuits.

Ladder-Type Circuits Revisited

ERIC Educational Resources Information Center

Yoon, Sung Hyun

2007-01-01

Ladder-type circuits where a given unit is repeated infinitely many times are dealt with in many textbooks on electromagnetism as examples of filter circuits. Determining the impedance of such circuits seems to be regarded as simple, which may be due to the fact that the invariance of the infinite system under the operation of adding one more unit…

Maximum Acceleration Recording Circuit

NASA Technical Reports Server (NTRS)

Bozeman, Richard J., Jr.

1995-01-01

Coarsely digitized maximum levels recorded in blown fuses. Circuit feeds power to accelerometer and makes nonvolatile record of maximum level to which output of accelerometer rises during measurement interval. In comparison with inertia-type single-preset-trip-point mechanical maximum-acceleration-recording devices, circuit weighs less, occupies less space, and records accelerations within narrower bands of uncertainty. In comparison with prior electronic data-acquisition systems designed for same purpose, circuit simpler, less bulky, consumes less power, costs and analysis of data recorded in magnetic or electronic memory devices. Circuit used, for example, to record accelerations to which commodities subjected during transportation on trucks.

Four-junction superconducting circuit

PubMed Central

Qiu, Yueyin; Xiong, Wei; He, Xiao-Ling; Li, Tie-Fu; You, J. Q.

2016-01-01

We develop a theory for the quantum circuit consisting of a superconducting loop interrupted by four Josephson junctions and pierced by a magnetic flux (either static or time-dependent). In addition to the similarity with the typical three-junction flux qubit in the double-well regime, we demonstrate the difference of the four-junction circuit from its three-junction analogue, including its advantages over the latter. Moreover, the four-junction circuit in the single-well regime is also investigated. Our theory provides a tool to explore the physical properties of this four-junction superconducting circuit. PMID:27356619

Solid state remote circuit selector switch

NASA Technical Reports Server (NTRS)

Peterson, V. S.

1970-01-01

Remote switching circuit utilizes voltage logic to switch on desired circuit. Circuit controls rotating multi-range pressure transducers in jet engine testing and can be used in coded remote circuit activator where sequence of switching has to occur in defined length of time to prevent false or undesired circuit activation.

Vibration Damping Circuit Card Assembly

NASA Technical Reports Server (NTRS)

Hunt, Ronald Allen (Inventor)

2016-01-01

A vibration damping circuit card assembly includes a populated circuit card having a mass M. A closed metal container is coupled to a surface of the populated circuit card at approximately a geometric center of the populated circuit card. Tungsten balls fill approximately 90% of the metal container with a collective mass of the tungsten balls being approximately (0.07) M.

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

Code of Federal Regulations, 2011 CFR

2011-07-01

...-phase alternating current equipment; circuit breakers. 75.900 Section 75.900 Mineral Resources MINE... Low- and medium-voltage circuits serving three-phase alternating current equipment; circuit breakers. [Statutory Provisions] Low- and medium-voltage power circuits serving three-phase alternating current...

Electric Circuit Model Analogy for Equilibrium Lattice Relaxation in Semiconductor Heterostructures

NASA Astrophysics Data System (ADS)

Kujofsa, Tedi; Ayers, John E.

2018-01-01

theory, using lumped circuit elements, to electromagnetics, using distributed electrical quantities. We show this development using first principles, but, in a more general sense, Maxwell's equations of electromagnetics could be applied.

TRIPPING CIRCUIT

DOEpatents

Lees, G.W.; McCormick, E.D.

1962-05-22

A tripping circuit employing a magnetic amplifier for tripping a reactor in response to power level, period, or instrument failure is described. A reference winding and signal winding are wound in opposite directions on the core. Current from an ion chamber passes through both windings. If the current increases at too fast a rate, a shunt circuit bypasses one or the windings and the amplifier output reverses polarity. (AEC)

Integrated coherent matter wave circuits

DOE PAGES

Ryu, C.; Boshier, M. G.

2015-09-21

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 theirmore » 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.« less

Liquid detection circuit

DOEpatents

Regan, Thomas O.

1987-01-01

Herein is a circuit which is capable of detecting the presence of liquids, especially cryogenic liquids, and whose sensor will not overheat in a vacuum. The circuit parameters, however, can be adjusted to work with any liquid over a wide range of temperatures.

Amplifier improvement circuit

NASA Technical Reports Server (NTRS)

Sturman, J.

1968-01-01

Stable input stage was designed for the use with a integrated circuit operational amplifier to provide improved performance as an instrumentation-type amplifier. The circuit provides high input impedance, stable gain, good common mode rejection, very low drift, and low output impedance.

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

Code of Federal Regulations, 2010 CFR

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...

A neural circuit for gamma-band coherence across the retinotopic map in mouse visual cortex

PubMed Central

Hakim, Richard; Shamardani, Kiarash

2018-01-01

Cortical gamma oscillations have been implicated in a variety of cognitive, behavioral, and circuit-level phenomena. However, the circuit mechanisms of gamma-band generation and synchronization across cortical space remain uncertain. Using optogenetic patterned illumination in acute brain slices of mouse visual cortex, we define a circuit composed of layer 2/3 (L2/3) pyramidal cells and somatostatin (SOM) interneurons that phase-locks ensembles across the retinotopic map. The network oscillations generated here emerge from non-periodic stimuli, and are stimulus size-dependent, coherent across cortical space, narrow band (30 Hz), and depend on SOM neuron but not parvalbumin (PV) neuron activity; similar to visually induced gamma oscillations observed in vivo. Gamma oscillations generated in separate cortical locations exhibited high coherence as far apart as 850 μm, and lateral gamma entrainment depended on SOM neuron activity. These data identify a circuit that is sufficient to mediate long-range gamma-band coherence in the primary visual cortex. PMID:29480803

Research on burnout fault of moulded case circuit breaker based on finite element simulation

NASA Astrophysics Data System (ADS)

Xue, Yang; Chang, Shuai; Zhang, Penghe; Xu, Yinghui; Peng, Chuning; Shi, Erwei

2017-09-01

In the failure event of molded case circuit breaker, overheating of the molded case near the wiring terminal has a very important proportion. The burnout fault has become an important factor restricting the development of molded case circuit breaker. This paper uses the finite element simulation software to establish the model of molded case circuit breaker by coupling multi-physics field. This model can simulate the operation and study the law of the temperature distribution. The simulation results show that the temperature near the wiring terminal, especially the incoming side of the live wire, of the molded case circuit breaker is much higher than that of the other areas. The steady-state and transient simulation results show that the temperature at the wiring terminals is abnormally increased by increasing the contact resistance of the wiring terminals. This is consistent with the frequent occurrence of burnout of the molded case in this area. Therefore, this paper holds that the burnout failure of the molded case circuit breaker is mainly caused by the abnormal increase of the contact resistance of the wiring terminal.

Life cycle assessment of overhead and underground primary power distribution.

PubMed

Bumby, Sarah; Druzhinina, Ekaterina; Feraldi, Rebe; Werthmann, Danae; Geyer, Roland; Sahl, Jack

2010-07-15

Electrical power can be distributed in overhead or underground systems, both of which generate a variety of environmental impacts at all stages of their life cycles. While there is considerable literature discussing the trade-offs between both systems in terms of aesthetics, safety, cost, and reliability, environmental assessments are relatively rare and limited to power cable production and end-of-life management. This paper assesses environmental impacts from overhead and underground medium voltage power distribution systems as they are currently built and managed by Southern California Edison (SCE). It uses process-based life cycle assessment (LCA) according to ISO 14044 (2006) and SCE-specific primary data to the extent possible. Potential environmental impacts have been calculated using a wide range of midpoint indicators, and robustness of the results has been investigated through sensitivity analysis of the most uncertain and potentially significant parameters. The studied underground system has higher environmental impacts in all indicators and for all parameter values, mostly due to its higher material intensity. For both systems and all indicators the majority of impact occurs during cable production. Promising strategies for impact reduction are thus cable failure rate reduction for overhead and cable lifetime extension for underground systems.

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

Code of Federal Regulations, 2010 CFR

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...

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

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Low- and medium-voltage circuits serving three... STANDARDS-UNDERGROUND COAL MINES Underground Low- and Medium-Voltage Alternating Current Circuits § 75.900 Low- and medium-voltage circuits serving three-phase alternating current equipment; circuit breakers...

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

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Low- and medium-voltage circuits serving three... STANDARDS-UNDERGROUND COAL MINES Underground Low- and Medium-Voltage Alternating Current Circuits § 75.900 Low- and medium-voltage circuits serving three-phase alternating current equipment; circuit breakers...

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

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Low- and medium-voltage circuits serving three... STANDARDS-UNDERGROUND COAL MINES Underground Low- and Medium-Voltage Alternating Current Circuits § 75.900 Low- and medium-voltage circuits serving three-phase alternating current equipment; circuit breakers...

Reconfigurable Optical Directed-Logic Circuits

DTIC Science & Technology

2015-11-20

AFRL-AFOSR-VA-TR-2016-0053 Reconfigurable Optical Directed-Logic Circuits Jacob Robinson WILLIAM MARSH RICE UNIV HOUSTON TX Final Report 11/20/2015...2015 Reconfigurable Optical Directed-Logic Circuits FA9550-12-1-0261 FA9550-12-1-0261 Robinson, Jacob Rice University 6100 Main Street Houston...Optical Directed-Logic Circuits Jacob T. Robinson and Qianfan Xu Rice University 1. Motivation for Directed-Logic Circuits Directed-logic is

Modeling of corrosion product migration in the secondary circuit of nuclear power plants with WWER-1200

NASA Astrophysics Data System (ADS)

Kritskii, V. G.; Berezina, I. G.; Gavrilov, A. V.; Motkova, E. A.; Zelenina, E. V.; Prokhorov, N. A.; Gorbatenko, S. P.; Tsitser, A. A.

2016-04-01

Models of corrosion and mass transfer of corrosion products in the pipes of the condensate-feeding and steam paths of the secondary circuit of NPPs with WWER-1200 are presented. The mass transfer and distribution of corrosion products over the currents of the working medium of the secondary circuit were calculated using the physicochemical model of mass transfer of corrosion products in which the secondary circuit is regarded as a cyclic system consisting of a number of interrelated elements. The circuit was divided into calculated regions in which the change in the parameters (flow rate, temperature, and pressure) was traced and the rates of corrosion and corrosion products entrainment, high-temperature pH, and iron concentration were calculated. The models were verified according to the results of chemical analyses at Kalinin NPP and iron corrosion product concentrations in the feed water at different NPPs depending on pH at 25°C (pH25) for service times τ ≥ 5000 h. The calculated pH values at a coolant temperature t (pH t ) in the secondary circuit of NPPs with WWER-1200 were presented. The calculation of the distribution of pH t and ethanolamine and ammonia concentrations over the condensate feed (CFC) and steam circuits is given. The models are designed for developing the calculation codes. The project solutions of ATOMPROEKT satisfy the safety and reliability requirements for power plants with WWER-1200. The calculated corrosion and corrosion product mass transfer parameters showed that the model allows the designer to choose between the increase of the correcting reagent concentration, the use of steel with higher chromium contents, and intermittent washing of the steam generator from sediments as the best solution for definite regions of the circuit.

Power-Switching Circuit

NASA Technical Reports Server (NTRS)

Praver, Gerald A.; Theisinger, Peter C.; Genofsky, John

1987-01-01

Functions of circuit breakers, meters, and switches combined. Circuit that includes power field-effect transistors (PFET's) provides on/off switching, soft starting, current monitoring, current tripping, and protection against overcurrent for 30-Vdc power supply at normal load currents up to 2 A. Has no moving parts.

Primary and Aggregate Size Distributions of PM in Tail Pipe Emissions form Diesel Engines

NASA Astrophysics Data System (ADS)

Arai, Masataka; Amagai, Kenji; Nakaji, Takayuki; Hayashi, Shinji

Particulate matter (PM) emission exhausted from diesel engine should be reduced to keep the clean air environment. PM emission was considered that it consisted of coarse and aggregate particles, and nuclei-mode particles of which diameter was less than 50nm. However the detail characteristics about these particles of the PM were still unknown and they were needed for more physically accurate measurement and more effective reduction of exhaust PM emission. In this study, the size distributions of solid particles in PM emission were reported. PMs in the tail-pipe emission were sampled from three type diesel engines. Sampled PM was chemically treated to separate the solid carbon fraction from other fractions such as soluble organic fraction (SOF). The electron microscopic and optical-manual size measurement procedures were used to determine the size distribution of primary particles those were formed through coagulation process from nuclei-mode particles and consisted in aggregate particles. The centrifugal sedimentation method was applied to measure the Stokes diameter of dry-soot. Aerodynamic diameters of nano and aggregate particles were measured with scanning mobility particle sizer (SMPS). The peak aggregate diameters detected by SMPS were fallen in the same size regime as the Stokes diameter of dry-soot. Both of primary and Stokes diameters of dry-soot decreased with increases of engine speed and excess air ratio. Also, the effects of fuel properties and engine types on primary and aggregate particle diameters were discussed.

Striatal Circuits as a Common Node for Autism Pathophysiology

PubMed Central

Fuccillo, Marc V.

2016-01-01

Autism spectrum disorders (ASD) are characterized by two seemingly unrelated symptom domains—deficits in social interactions and restrictive, repetitive patterns of behavioral output. Whether the diverse nature of ASD symptomatology represents distributed dysfunction of brain networks or abnormalities within specific neural circuits is unclear. Striatal dysfunction is postulated to underlie the repetitive motor behaviors seen in ASD, and neurological and brain-imaging studies have supported this assumption. However, as our appreciation of striatal function expands to include regulation of behavioral flexibility, motivational state, goal-directed learning, and attention, we consider whether alterations in striatal physiology are a central node mediating a range of autism-associated behaviors, including social and cognitive deficits that are hallmarks of the disease. This review investigates multiple genetic mouse models of ASD to explore whether abnormalities in striatal circuits constitute a common pathophysiological mechanism in the development of autism-related behaviors. Despite the heterogeneity of genetic insult investigated, numerous genetic ASD models display alterations in the structure and function of striatal circuits, as well as abnormal behaviors including repetitive grooming, stereotypic motor routines, deficits in social interaction and decision-making. Comparative analysis in rodents provides a unique opportunity to leverage growing genetic association data to reveal canonical neural circuits whose dysfunction directly contributes to discrete aspects of ASD symptomatology. The description of such circuits could provide both organizing principles for understanding the complex genetic etiology of ASD as well as novel treatment routes. Furthermore, this focus on striatal mechanisms of behavioral regulation may also prove useful for exploring the pathogenesis of other neuropsychiatric diseases, which display overlapping behavioral deficits with ASD

Mercury distribution characteristics in primary manganese smelting plants.

PubMed

Back, Seung-Ki; Sung, Jin-Ho; Moon, Young-Hoon; Kim, Young-Hee; Seok, Kwang-Seol; Song, Geum-Ju; Seo, Yong-Chil

2017-08-01

The mercury (Hg) distribution characteristics were investigated in three primary manganese smelting plants in Korea for the assessment of anthropogenic Hg released. Input and output materials were sampled from each process, and Hg concentrations in the samples were analyzed. Among the input materials, the most mercury was found in the manganese ore (83.1-99.7%) and mercury was mainly released through fly ash or off gas, depending on the condition of off gas cleaning system. As off gas temperature decreases, proportion and concentration of emitted gaseous elemental mercury (Hg 0 ) in off gas decreases. Based on mass balance study from these three plants and national manganese production data, the total amount of mercury released from those Korean plants was estimated to 644 kg/yr. About half of it was emitted into the air while the rest was released to waste as fly ash. With the results of this investigation, national inventory for Hg emission and release could be updated for the response to Minamata Convention on Mercury. Copyright © 2017. Published by Elsevier Ltd.

46 CFR 111.97-7 - Distribution.

Code of Federal Regulations, 2012 CFR

2012-10-01

... REQUIREMENTS Electric Power-Operated Watertight Door Systems § 111.97-7 Distribution. (a) Each distribution... locking. (b) Each feeder supplying a watertight door operating system must be above the uppermost continuous deck. (c) Each watertight door operating system must have a separate branch circuit. ...

46 CFR 111.97-7 - Distribution.

Code of Federal Regulations, 2011 CFR

2011-10-01

... REQUIREMENTS Electric Power-Operated Watertight Door Systems § 111.97-7 Distribution. (a) Each distribution... locking. (b) Each feeder supplying a watertight door operating system must be above the uppermost continuous deck. (c) Each watertight door operating system must have a separate branch circuit. ...

46 CFR 111.97-7 - Distribution.

Code of Federal Regulations, 2010 CFR

2010-10-01

... REQUIREMENTS Electric Power-Operated Watertight Door Systems § 111.97-7 Distribution. (a) Each distribution... locking. (b) Each feeder supplying a watertight door operating system must be above the uppermost continuous deck. (c) Each watertight door operating system must have a separate branch circuit. ...

46 CFR 111.97-7 - Distribution.

Code of Federal Regulations, 2014 CFR

2014-10-01

... REQUIREMENTS Electric Power-Operated Watertight Door Systems § 111.97-7 Distribution. (a) Each distribution... locking. (b) Each feeder supplying a watertight door operating system must be above the uppermost continuous deck. (c) Each watertight door operating system must have a separate branch circuit. ...

46 CFR 111.97-7 - Distribution.

Code of Federal Regulations, 2013 CFR

2013-10-01

... REQUIREMENTS Electric Power-Operated Watertight Door Systems § 111.97-7 Distribution. (a) Each distribution... locking. (b) Each feeder supplying a watertight door operating system must be above the uppermost continuous deck. (c) Each watertight door operating system must have a separate branch circuit. ...

Protective Socket For Integrated Circuits

NASA Technical Reports Server (NTRS)

Wilkinson, Chris; Henegar, Greg

1988-01-01

Socket for intergrated circuits (IC's) protects from excessive voltages and currents or from application of voltages and currents in wrong sequence during insertion or removal. Contains built-in switch that opens as IC removed, disconnecting leads from signals and power. Also protects other components on circuit board from transients produced by insertion and removal of IC. Makes unnecessary to turn off power to entire circuit board so other circuits on board continue to function.

A Quantitative Study of the Relationship between Distributed Leadership and Organizational Citizenship Behavior: Perceptions of Turkish Primary School Teachers

ERIC Educational Resources Information Center

Kilinç, Ali Çagatay

2014-01-01

The purpose of this study was to determine the relationship between primary school teachers' perceptions on distributed leadership and organizational citizenship behaviors (OCBs). A total of 258 teachers employed in 14 primary schools located in Kastamonu, Turkey participated in this study. Data of the study was collected through "Distributed…

Submicrosecond Power-Switching Test Circuit

NASA Technical Reports Server (NTRS)

Folk, Eric N.

2006-01-01

A circuit that changes an electrical load in a switching time shorter than 0.3 microsecond has been devised. This circuit can be used in testing the regulation characteristics of power-supply circuits . especially switching power-converter circuits that are supposed to be able to provide acceptably high degrees of regulation in response to rapid load transients. The combination of this power-switching circuit and a known passive constant load could be an attractive alternative to a typical commercially available load-bank circuit that can be made to operate in nominal constant-voltage, constant-current, and constant-resistance modes. The switching provided by a typical commercial load-bank circuit in the constant-resistance mode is not fast enough for testing of regulation in response to load transients. Moreover, some test engineers do not trust the test results obtained when using commercial load-bank circuits because the dynamic responses of those circuits are, variously, partly unknown and/or excessively complex. In contrast, the combination of this circuit and a passive constant load offers both rapid switching and known (or at least better known) load dynamics. The power-switching circuit (see figure) includes a signal-input section, a wide-hysteresis Schmitt trigger that prevents false triggering in the event of switch-contact bounce, a dual-bipolar-transistor power stage that drives the gate of a metal oxide semiconductor field-effect transistor (MOSFET), and the MOSFET, which is the output device that performs the switching of the load. The MOSFET in the specific version of the circuit shown in the figure is rated to stand off a potential of 100 V in the "off" state and to pass a current of 20 A in the "on" state. The switching time of this circuit (the characteristic time of rise or fall of the potential at the drain of the MOSFET) is .300 ns. The circuit can accept any of three control inputs . which one depending on the test that one seeks to perform: a

Distribution of Primary School Enrollments in Eastern Africa. World Bank Staff Working Papers Number 511.

ERIC Educational Resources Information Center

Maas, Jacob van Lutsenburg; Criel, Geert

Distribution of primary school enrollments within and among 15 countries of the Eastern African region was examined by drawing exclusively on routine annual statistics and by emphasizing simple computer-generated indicators. In its first phase, the study made inter-country comparisons that indicated which countries and which areas in the region…

Development and Simulation of Increased Generation on a Secondary Circuit of a Microgrid

NASA Astrophysics Data System (ADS)

Reyes, Karina

As fossil fuels are depleted and their environmental impacts remain, other sources of energy must be considered to generate power. Renewable sources, for example, are emerging to play a major role in this regard. In parallel, electric vehicle (EV) charging is evolving as a major load demand. To meet reliability and resiliency goals demanded by the electricity market, interest in microgrids are growing as a distributed energy resource (DER). In this thesis, the effects of intermittent renewable power generation and random EV charging on secondary microgrid circuits are analyzed in the presence of a controllable battery in order to characterize and better understand the dynamics associated with intermittent power production and random load demands in the context of the microgrid paradigm. For two reasons, a secondary circuit on the University of California, Irvine (UCI) Microgrid serves as the case study. First, the secondary circuit (UC-9) is heavily loaded and an integral component of a highly characterized and metered microgrid. Second, a unique "next-generation" distributed energy resource has been deployed at the end of the circuit that integrates photovoltaic power generation, battery storage, and EV charging. In order to analyze this system and evaluate the impact of the DER on the secondary circuit, a model was developed to provide a real-time load flow analysis. The research develops a power management system applicable to similarly integrated systems. The model is verified by metered data obtained from a network of high resolution electric meters and estimated load data for the buildings that have unknown demand. An increase in voltage is observed when the amount of photovoltaic power generation is increased. To mitigate this effect, a constant power factor is set. Should the real power change dramatically, the reactive power is changed to mitigate voltage fluctuations.

Electroshock protection circuit

NASA Technical Reports Server (NTRS)

Heskett, H.; Meincer, J.; Inglis, A. L.

1973-01-01

Circuit was developed to prevent accidental shock through electrodes used to test subjects as part of Skylab program. This circuit is placed between electrical apparatus and electrode that is attached to patient's body. Thus, patient is effectively protected from dangerous electrical shock that might be caused by failure in electrical apparatus.

Methods of fabricating applique circuits

DOEpatents

Dimos, Duane B.; Garino, Terry J.

1999-09-14

Applique circuits suitable for advanced packaging applications are introduced. These structures are particularly suited for the simple integration of large amounts (many nanoFarads) of capacitance into conventional integrated circuit and multichip packaging technology. In operation, applique circuits are bonded to the integrated circuit or other appropriate structure at the point where the capacitance is required, thereby minimizing the effects of parasitic coupling. An immediate application is to problems of noise reduction and control in modern high-frequency circuitry.

Integrated circuit cooled turbine blade

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Ching-Pang; Jiang, Nan; Um, Jae Y.

A turbine rotor blade includes at least two integrated cooling circuits that are formed within the blade that include a leading edge circuit having a first cavity and a second cavity and a trailing edge circuit that includes at least a third cavity located aft of the second cavity. The trailing edge circuit flows aft with at least two substantially 180-degree turns at the tip end and the root end of the blade providing at least a penultimate cavity and a last cavity. The last cavity is located along a trailing edge of the blade. A tip axial cooling channelmore » connects to the first cavity of the leading edge circuit and the penultimate cavity of the trailing edge circuit. At least one crossover hole connects the penultimate cavity to the last cavity substantially near the tip end of the blade.« less

Automated Design of Quantum Circuits

NASA Technical Reports Server (NTRS)

Williams, Colin P.; Gray, Alexander G.

2000-01-01

In order to design a quantum circuit that performs a desired quantum computation, it is necessary to find a decomposition of the unitary matrix that represents that computation in terms of a sequence of quantum gate operations. To date, such designs have either been found by hand or by exhaustive enumeration of all possible circuit topologies. In this paper we propose an automated approach to quantum circuit design using search heuristics based on principles abstracted from evolutionary genetics, i.e. using a genetic programming algorithm adapted specially for this problem. We demonstrate the method on the task of discovering quantum circuit designs for quantum teleportation. We show that to find a given known circuit design (one which was hand-crafted by a human), the method considers roughly an order of magnitude fewer designs than naive enumeration. In addition, the method finds novel circuit designs superior to those previously known.

Parallelism in integrated fluidic circuits

NASA Astrophysics Data System (ADS)

Bousse, Luc J.; Kopf-Sill, Anne R.; Parce, J. W.

1998-04-01

Many research groups around the world are working on integrated microfluidics. The goal of these projects is to automate and integrate the handling of liquid samples and reagents for measurement and assay procedures in chemistry and biology. Ultimately, it is hoped that this will lead to a revolution in chemical and biological procedures similar to that caused in electronics by the invention of the integrated circuit. The optimal size scale of channels for liquid flow is determined by basic constraints to be somewhere between 10 and 100 micrometers . In larger channels, mixing by diffusion takes too long; in smaller channels, the number of molecules present is so low it makes detection difficult. At Caliper, we are making fluidic systems in glass chips with channels in this size range, based on electroosmotic flow, and fluorescence detection. One application of this technology is rapid assays for drug screening, such as enzyme assays and binding assays. A further challenge in this area is to perform multiple functions on a chip in parallel, without a large increase in the number of inputs and outputs. A first step in this direction is a fluidic serial-to-parallel converter. Fluidic circuits will be shown with the ability to distribute an incoming serial sample stream to multiple parallel channels.

Data on the natural ventilation performance of windcatcher with anti-short-circuit device (ASCD).

PubMed

Nejat, Payam; Calautit, John Kaiser; Majid, Muhd Zaimi Abd; Hughes, Ben Richard; Jomehzadeh, Fatemeh

2016-12-01

This article presents the datasets which were the results of the study explained in the research paper 'Anti-short-circuit device: a new solution for short-circuiting in windcatcher and improvement of natural ventilation performance' (P. Nejat, J.K. Calautit, M.Z. Abd. Majid, B.R. Hughes, F. Jomehzadeh, 2016) [1] which introduces a new technique to reduce or prevent short-circuiting in a two-sided windcatcher and also lowers the indoor CO2 concentration and improve the ventilation distribution. Here, we provide details of the numerical modeling set-up and data collection method to facilitate reproducibility. The datasets includes indoor airflow, ventilation rates and CO2 concentration data at several points in the flow field. The CAD geometry of the windcatcher models are also included.

Habenula Circuit Development: Past, Present, and Future

PubMed Central

Beretta, Carlo A.; Dross, Nicolas; Guiterrez-Triana, Jose A.; Ryu, Soojin; Carl, Matthias

2012-01-01

The habenular neural circuit is attracting increasing attention from researchers in fields as diverse as neuroscience, medicine, behavior, development, and evolution. Recent studies have revealed that this part of the limbic system in the dorsal diencephalon is involved in reward, addiction, and other behaviors and its impairment is associated with various neurological conditions and diseases. Since the initial description of the dorsal diencephalic conduction system (DDC) with the habenulae in its center at the end of the nineteenth century, increasingly sophisticated techniques have resolved much of its anatomy and have shown that these pathways relay information from different parts of the forebrain to the tegmentum, midbrain, and hindbrain. The first part of this review gives a brief historical overview on how the improving experimental approaches have allowed the stepwise uncovering much of the architecture of the habenula circuit as we know it today. Our brain distributes tasks differentially between left and right and it has become a paradigm that this functional lateralization is a universal feature of vertebrates. Moreover, task dependent differential brain activities have been linked to anatomical differences across the left–right axis in humans. A good way to further explore this fundamental issue will be to study the functional consequences of subtle changes in neural network formation, which requires that we fully understand DDC system development. As the habenular circuit is evolutionarily highly conserved, researchers have the option to perform such difficult experiments in more experimentally amenable vertebrate systems. Indeed, research in the last decade has shown that the zebrafish is well suited for the study of DDC system development and the phenomenon of functional lateralization. We will critically discuss the advantages of the zebrafish model, available techniques, and others that are needed to fully understand habenular circuit

Habenula circuit development: past, present, and future.

PubMed

Beretta, Carlo A; Dross, Nicolas; Guiterrez-Triana, Jose A; Ryu, Soojin; Carl, Matthias

2012-01-01

The habenular neural circuit is attracting increasing attention from researchers in fields as diverse as neuroscience, medicine, behavior, development, and evolution. Recent studies have revealed that this part of the limbic system in the dorsal diencephalon is involved in reward, addiction, and other behaviors and its impairment is associated with various neurological conditions and diseases. Since the initial description of the dorsal diencephalic conduction system (DDC) with the habenulae in its center at the end of the nineteenth century, increasingly sophisticated techniques have resolved much of its anatomy and have shown that these pathways relay information from different parts of the forebrain to the tegmentum, midbrain, and hindbrain. The first part of this review gives a brief historical overview on how the improving experimental approaches have allowed the stepwise uncovering much of the architecture of the habenula circuit as we know it today. Our brain distributes tasks differentially between left and right and it has become a paradigm that this functional lateralization is a universal feature of vertebrates. Moreover, task dependent differential brain activities have been linked to anatomical differences across the left-right axis in humans. A good way to further explore this fundamental issue will be to study the functional consequences of subtle changes in neural network formation, which requires that we fully understand DDC system development. As the habenular circuit is evolutionarily highly conserved, researchers have the option to perform such difficult experiments in more experimentally amenable vertebrate systems. Indeed, research in the last decade has shown that the zebrafish is well suited for the study of DDC system development and the phenomenon of functional lateralization. We will critically discuss the advantages of the zebrafish model, available techniques, and others that are needed to fully understand habenular circuit development.

Matrix Metalloproteinase-9 regulates neuronal circuit development and excitability

PubMed Central

Murase, Sachiko; Lantz, Crystal; Kim, Eunyoung; Gupta, Nitin; Higgins, Richard; Stopfer, Mark; Hoffman, Dax A.; Quinlan, Elizabeth M.

2015-01-01

In early postnatal development, naturally occurring cell death, dendritic outgrowth and synaptogenesis sculpt neuronal ensembles into functional neuronal circuits. Here we demonstrate that deletion of the extracellular proteinase MMP-9 affects each of these processes, resulting in maladapted neuronal circuitry. MMP-9 deletion increases the number of CA1 pyramidal neurons, but decreases dendritic length and complexity while dendritic spine density is unchanged. Parallel changes in neuronal morphology are observed in primary visual cortex, and persist into adulthood. Individual CA1 neurons in MMP-9−/− mice have enhanced input resistance and a significant increase in the frequency, but not amplitude, of miniature excitatory postsynaptic currents (mEPSCs). Additionally, deletion of MMP-9 significant increases spontaneous neuronal activity in awake MMP-9−/− mice and enhances response to acute challenge by the excitotoxin kainate. Thus MMP-9-dependent proteolysis regulates several aspects of circuit maturation to constrain excitability throughout life. PMID:26093382

Digital model of a vacuum circuit breaker for the analysis of switching waveforms in electrical circuits

NASA Astrophysics Data System (ADS)

Budzisz, Joanna; Wróblewski, Zbigniew

2016-03-01

The article presents a method of modelling a vaccum circuit breaker in the ATP/EMTP package, the results of the verification of the correctness of the developed digital circuit breaker model operation and its practical usefulness for analysis of overvoltages and overcurrents occurring in commutated capacitive electrical circuits and also examples of digital simulations of overvoltages and overcurrents in selected electrical circuits.

Muscle spindle feedback directs locomotor recovery and circuit reorganization after spinal cord injury.

PubMed

Takeoka, Aya; Vollenweider, Isabel; Courtine, Grégoire; Arber, Silvia

2014-12-18

Spinal cord injuries alter motor function by disconnecting neural circuits above and below the lesion, rendering sensory inputs a primary source of direct external drive to neuronal networks caudal to the injury. Here, we studied mice lacking functional muscle spindle feedback to determine the role of this sensory channel in gait control and locomotor recovery after spinal cord injury. High-resolution kinematic analysis of intact mutant mice revealed proficient execution in basic locomotor tasks but poor performance in a precision task. After injury, wild-type mice spontaneously recovered basic locomotor function, whereas mice with deficient muscle spindle feedback failed to regain control over the hindlimb on the lesioned side. Virus-mediated tracing demonstrated that mutant mice exhibit defective rearrangements of descending circuits projecting to deprived spinal segments during recovery. Our findings reveal an essential role for muscle spindle feedback in directing basic locomotor recovery and facilitating circuit reorganization after spinal cord injury. Copyright © 2014 Elsevier Inc. All rights reserved.

A plausible neural circuit for decision making and its formation based on reinforcement learning.

PubMed

Wei, Hui; Dai, Dawei; Bu, Yijie

2017-06-01

A human's, or lower insects', behavior is dominated by its nervous system. Each stable behavior has its own inner steps and control rules, and is regulated by a neural circuit. Understanding how the brain influences perception, thought, and behavior is a central mandate of neuroscience. The phototactic flight of insects is a widely observed deterministic behavior. Since its movement is not stochastic, the behavior should be dominated by a neural circuit. Based on the basic firing characteristics of biological neurons and the neural circuit's constitution, we designed a plausible neural circuit for this phototactic behavior from logic perspective. The circuit's output layer, which generates a stable spike firing rate to encode flight commands, controls the insect's angular velocity when flying. The firing pattern and connection type of excitatory and inhibitory neurons are considered in this computational model. We simulated the circuit's information processing using a distributed PC array, and used the real-time average firing rate of output neuron clusters to drive a flying behavior simulation. In this paper, we also explored how a correct neural decision circuit is generated from network flow view through a bee's behavior experiment based on the reward and punishment feedback mechanism. The significance of this study: firstly, we designed a neural circuit to achieve the behavioral logic rules by strictly following the electrophysiological characteristics of biological neurons and anatomical facts. Secondly, our circuit's generality permits the design and implementation of behavioral logic rules based on the most general information processing and activity mode of biological neurons. Thirdly, through computer simulation, we achieved new understanding about the cooperative condition upon which multi-neurons achieve some behavioral control. Fourthly, this study aims in understanding the information encoding mechanism and how neural circuits achieve behavior control

49 CFR 236.303 - Control circuits for signals, selection through circuit controller operated by switch points or...

Code of Federal Regulations, 2010 CFR

2010-10-01

... circuit controller operated by switch points or by switch locking mechanism. 236.303 Section 236.303... § 236.303 Control circuits for signals, selection through circuit controller operated by switch points or by switch locking mechanism. The control circuit for each aspect with indication more favorable...

49 CFR 236.303 - Control circuits for signals, selection through circuit controller operated by switch points or...

Code of Federal Regulations, 2012 CFR

2012-10-01

... circuit controller operated by switch points or by switch locking mechanism. 236.303 Section 236.303... § 236.303 Control circuits for signals, selection through circuit controller operated by switch points or by switch locking mechanism. The control circuit for each aspect with indication more favorable...

49 CFR 236.303 - Control circuits for signals, selection through circuit controller operated by switch points or...

Code of Federal Regulations, 2013 CFR

2013-10-01

... circuit controller operated by switch points or by switch locking mechanism. 236.303 Section 236.303... § 236.303 Control circuits for signals, selection through circuit controller operated by switch points or by switch locking mechanism. The control circuit for each aspect with indication more favorable...

49 CFR 236.303 - Control circuits for signals, selection through circuit controller operated by switch points or...

Code of Federal Regulations, 2014 CFR

2014-10-01

... circuit controller operated by switch points or by switch locking mechanism. 236.303 Section 236.303... § 236.303 Control circuits for signals, selection through circuit controller operated by switch points or by switch locking mechanism. The control circuit for each aspect with indication more favorable...

49 CFR 236.303 - Control circuits for signals, selection through circuit controller operated by switch points or...

Code of Federal Regulations, 2011 CFR

2011-10-01

... circuit controller operated by switch points or by switch locking mechanism. 236.303 Section 236.303... § 236.303 Control circuits for signals, selection through circuit controller operated by switch points or by switch locking mechanism. The control circuit for each aspect with indication more favorable...

Microfluidic Serial Dilution Circuit

PubMed Central

Paegel, Brian M.; Grover, William H.; Skelley, Alison M.; Mathies, Richard A.; Joyce, Gerald F.

2008-01-01

In vitro evolution of RNA molecules requires a method for executing many consecutive serial dilutions. To solve this problem, a microfluidic circuit has been fabricated in a three-layer glass-PDMS-glass device. The 400-nL serial dilution circuit contains five integrated membrane valves: three two-way valves arranged in a loop to drive cyclic mixing of the diluent and carryover, and two bus valves to control fluidic access to the circuit through input and output channels. By varying the valve placement in the circuit, carryover fractions from 0.04 to 0.2 were obtained. Each dilution process, which is comprised of a diluent flush cycle followed by a mixing cycle, is carried out with no pipeting, and a sample volume of 400 nL is sufficient for conducting an arbitrary number of serial dilutions. Mixing is precisely controlled by changing the cyclic pumping rate, with a minimum mixing time of 22 s. This microfluidic circuit is generally applicable for integrating automated serial dilution and sample preparation in almost any microfluidic architecture. PMID:17073422

Transfer-matrices for series-type microwave antenna circuits. [L-band radiometer

NASA Technical Reports Server (NTRS)

Schmidt, R. F.

1981-01-01

Transfer matrices are developed which permit analysis and computer evaluation of certain series type microwave antenna circuits associated with an L-Band microwave radiometer (LBMR) under investigation at Goddard Space Flight Center. This radiometer is one of several diverse instrument designs to be used for the determination of soil moisture, sea state, salinity, and temperature data. Four port matrix notation is used throughout for the evaluation of LBMR circuits with mismatched couplers and lossy transmission lines. Matrix parameters in examples are predicted on an impedance analysis and an assumption of an array aperture distribution. The notation presented is easily adapted to longer and more varied chains of matrices, and to matrices of larger dimension.

Novel high-gain, improved-bandwidth, finned-ladder V-band Traveling-Wave Tube slow-wave circuit design

NASA Technical Reports Server (NTRS)

Kory, Carol L.; Wilson, Jeffrey D.

1994-01-01

The V-band frequency range of 59-64 GHz is a region of the millimeter-wave spectrum that has been designated for inter-satellite communications. As a first effort to develop a high-efficiency V-band Traveling-Wave Tube (TWT), variations on a ring-plane slow-wave circuit were computationally investigated to develop an alternative to the more conventional ferruled coupled-cavity circuit. The ring-plane circuit was chosen because of its high interaction impedance, large beam aperture, and excellent thermal dissipation properties. Despite these advantages, however, low bandwidth and high voltage requirements have, until now, prevented its acceptance outside the laboratory. In this paper, the three-dimensional electrodynamic simulation code MAFIA (solution of MAxwell's Equation by the Finite-Integration-Algorithm) is used to investigate methods of increasing the bandwidth and lowering the operating voltage of the ring-plane circuit. Calculations of frequency-phase dispersion, beam on-axis interaction impedance, attenuation and small-signal gain per wavelength were performed for various geometric variations and loading distributions of the ring-plane TWT slow-wave circuit. Based on the results of the variations, a circuit termed the finned-ladder TWT slow-wave circuit was designed and is compared here to the scaled prototype ring-plane and a conventional ferruled coupled-cavity TWT circuit over the V-band frequency range. The simulation results indicate that this circuit has a much higher gain, significantly wider bandwidth, and a much lower voltage requirement than the scaled ring-plane prototype circuit, while retaining its excellent thermal dissipation properties. The finned-ladder circuit has a much larger small-signal gain per wavelength than the ferruled coupled-cavity circuit, but with a moderate sacrifice in bandwidth.

46 CFR 169.670 - Circuit breakers.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Gross Tons § 169.670 Circuit breakers. Each circuit breaker must be of the manually reset type designed for— (a) Inverse time delay; (b) Instantaneous short circuit protection; and (c) Repeated opening of... 46 Shipping 7 2010-10-01 2010-10-01 false Circuit breakers. 169.670 Section 169.670 Shipping COAST...

Integrated circuits, and design and manufacture thereof

DOEpatents

Auracher, Stefan; Pribbernow, Claus; Hils, Andreas

2006-04-18

A representation of a macro for an integrated circuit layout. The representation may define sub-circuit cells of a module. The module may have a predefined functionality. The sub-circuit cells may include at least one reusable circuit cell. The reusable circuit cell may be configured such that when the predefined functionality of the module is not used, the reusable circuit cell is available for re-use.

Computer Power: Part 1: Distribution of Power (and Communications).

ERIC Educational Resources Information Center

Price, Bennett J.

1988-01-01

Discussion of the distribution of power to personal computers and computer terminals addresses options such as extension cords, perimeter raceways, and interior raceways. Sidebars explain: (1) the National Electrical Code; (2) volts, amps, and watts; (3) transformers, circuit breakers, and circuits; and (4) power vs. data wiring. (MES)

Human Cerebrospinal Fluid Promotes Neuronal Viability and Activity of Hippocampal Neuronal Circuits In Vitro

PubMed Central

Perez-Alcazar, Marta; Culley, Georgia; Lyckenvik, Tim; Mobarrez, Kristoffer; Bjorefeldt, Andreas; Wasling, Pontus; Seth, Henrik; Asztely, Frederik; Harrer, Andrea; Iglseder, Bernhard; Aigner, Ludwig; Hanse, Eric; Illes, Sebastian

2016-01-01

For decades it has been hypothesized that molecules within the cerebrospinal fluid (CSF) diffuse into the brain parenchyma and influence the function of neurons. However, the functional consequences of CSF on neuronal circuits are largely unexplored and unknown. A major reason for this is the absence of appropriate neuronal in vitro model systems, and it is uncertain if neurons cultured in pure CSF survive and preserve electrophysiological functionality in vitro. In this article, we present an approach to address how human CSF (hCSF) influences neuronal circuits in vitro. We validate our approach by comparing the morphology, viability, and electrophysiological function of single neurons and at the network level in rat organotypic slice and primary neuronal cultures cultivated either in hCSF or in defined standard culture media. Our results demonstrate that rodent hippocampal slices and primary neurons cultured in hCSF maintain neuronal morphology and preserve synaptic transmission. Importantly, we show that hCSF increases neuronal viability and the number of electrophysiologically active neurons in comparison to the culture media. In summary, our data indicate that hCSF represents a physiological environment for neurons in vitro and a superior culture condition compared to the defined standard media. Moreover, this experimental approach paves the way to assess the functional consequences of CSF on neuronal circuits as well as suggesting a novel strategy for central nervous system (CNS) disease modeling. PMID:26973467

Magnetic compression laser driving circuit

DOEpatents

Ball, D.G.; Birx, D.; Cook, E.G.

1993-01-05

A magnetic compression laser driving circuit is disclosed. The magnetic compression laser driving circuit compresses voltage pulses in the range of 1.5 microseconds at 20 kilovolts of amplitude to pulses in the range of 40 nanoseconds and 60 kilovolts of amplitude. The magnetic compression laser driving circuit includes a multi-stage magnetic switch where the last stage includes a switch having at least two turns which has larger saturated inductance with less core material so that the efficiency of the circuit and hence the laser is increased.

Magnetic compression laser driving circuit

DOEpatents

Ball, Don G.; Birx, Dan; Cook, Edward G.

1993-01-01

A magnetic compression laser driving circuit is disclosed. The magnetic compression laser driving circuit compresses voltage pulses in the range of 1.5 microseconds at 20 Kilovolts of amplitude to pulses in the range of 40 nanoseconds and 60 Kilovolts of amplitude. The magnetic compression laser driving circuit includes a multi-stage magnetic switch where the last stage includes a switch having at least two turns which has larger saturated inductance with less core material so that the efficiency of the circuit and hence the laser is increased.

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

NASA Technical Reports Server (NTRS)

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.

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

NASA Technical Reports Server (NTRS)

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.

High voltage MOSFET switching circuit

DOEpatents

McEwan, Thomas E.

1994-01-01

The problem of source lead inductance in a MOSFET switching circuit is compensated for by adding an inductor to the gate circuit. The gate circuit inductor produces an inductive spike which counters the source lead inductive drop to produce a rectangular drive voltage waveform at the internal gate-source terminals of the MOSFET.

Compiling probabilistic, bio-inspired circuits on a field programmable analog array

PubMed Central

Marr, Bo; Hasler, Jennifer

2014-01-01

A field programmable analog array (FPAA) is presented as an energy and computational efficiency engine: a mixed mode processor for which functions can be compiled at significantly less energy costs using probabilistic computing circuits. More specifically, it will be shown that the core computation of any dynamical system can be computed on the FPAA at significantly less energy per operation than a digital implementation. A stochastic system that is dynamically controllable via voltage controlled amplifier and comparator thresholds is implemented, which computes Bernoulli random variables. From Bernoulli variables it is shown exponentially distributed random variables, and random variables of an arbitrary distribution can be computed. The Gillespie algorithm is simulated to show the utility of this system by calculating the trajectory of a biological system computed stochastically with this probabilistic hardware where over a 127X performance improvement over current software approaches is shown. The relevance of this approach is extended to any dynamical system. The initial circuits and ideas for this work were generated at the 2008 Telluride Neuromorphic Workshop. PMID:24847199

Difference-Equation/Flow-Graph Circuit Analysis

NASA Technical Reports Server (NTRS)

Mcvey, I. M.

1988-01-01

Numerical technique enables rapid, approximate analyses of electronic circuits containing linear and nonlinear elements. Practiced in variety of computer languages on large and small computers; for circuits simple enough, programmable hand calculators used. Although some combinations of circuit elements make numerical solutions diverge, enables quick identification of divergence and correction of circuit models to make solutions converge.

Bypassing An Open-Circuit Power Cell

NASA Technical Reports Server (NTRS)

Wannemacher, Harry E.

1994-01-01

Collection of bypass circuits enables battery consisting series string of cells to continue to function when one of its cells fails in open-circuit (high-resistance) condition. Basic idea simply to shunt current around defective cell to prevent open circuit from turning off battery altogether. Bypass circuits dissipate little power and are nearly immune to false activation.

Binary selectable detector holdoff circuit: Design, testing, and application. [to laser radar data acquisition system

NASA Technical Reports Server (NTRS)

Kadrmas, K. A.

1973-01-01

A very high speed switching circuit, part of a laser radar data acquisition system, has been designed and tested. The primary function of this circuit was to provide computer controlled switching of photodiode detector preamplifier power supply voltages, typically less than plus or minus 20 volts, in approximately 10 nanoseconds. Thus, in actual use, detector and/or detector preamplifier damage can be avoided as a result of sudden extremely large values of backscattered radiation being detected, such as might be due to short range, very thin atmospheric dust layers. Switching of the power supply voltages was chosen over direct switching the photodiode detector input to the preamplifier, based on system noise considerations. Also, the circuit provides a synchronized trigger pulse output for triggering devices such as the Biomation Model 8100 100 MHz analog to digital converter.

Graphene radio frequency receiver integrated circuit.

PubMed

Han, Shu-Jen; Garcia, Alberto Valdes; Oida, Satoshi; Jenkins, Keith A; Haensch, Wilfried

2014-01-01

Graphene has attracted much interest as a future channel material in radio frequency electronics because of its superior electrical properties. Fabrication of a graphene integrated circuit without significantly degrading transistor performance has proven to be challenging, posing one of the major bottlenecks to compete with existing technologies. Here we present a fabrication method fully preserving graphene transistor quality, demonstrated with the implementation of a high-performance three-stage graphene integrated circuit. The circuit operates as a radio frequency receiver performing signal amplification, filtering and downconversion mixing. All circuit components are integrated into 0.6 mm(2) area and fabricated on 200 mm silicon wafers, showing the unprecedented graphene circuit complexity and silicon complementary metal-oxide-semiconductor process compatibility. The demonstrated circuit performance allow us to use graphene integrated circuit to perform practical wireless communication functions, receiving and restoring digital text transmitted on a 4.3-GHz carrier signal.

Graphene radio frequency receiver integrated circuit

NASA Astrophysics Data System (ADS)

Han, Shu-Jen; Garcia, Alberto Valdes; Oida, Satoshi; Jenkins, Keith A.; Haensch, Wilfried

2014-01-01

Graphene has attracted much interest as a future channel material in radio frequency electronics because of its superior electrical properties. Fabrication of a graphene integrated circuit without significantly degrading transistor performance has proven to be challenging, posing one of the major bottlenecks to compete with existing technologies. Here we present a fabrication method fully preserving graphene transistor quality, demonstrated with the implementation of a high-performance three-stage graphene integrated circuit. The circuit operates as a radio frequency receiver performing signal amplification, filtering and downconversion mixing. All circuit components are integrated into 0.6 mm2 area and fabricated on 200 mm silicon wafers, showing the unprecedented graphene circuit complexity and silicon complementary metal-oxide-semiconductor process compatibility. The demonstrated circuit performance allow us to use graphene integrated circuit to perform practical wireless communication functions, receiving and restoring digital text transmitted on a 4.3-GHz carrier signal.

MULTIPLIER CIRCUIT

DOEpatents

Chase, R.L.

1963-05-01

An electronic fast multiplier circuit utilizing a transistor controlled voltage divider network is presented. The multiplier includes a stepped potentiometer in which solid state or transistor switches are substituted for mechanical wipers in order to obtain electronic switching that is extremely fast as compared to the usual servo-driven mechanical wipers. While this multiplier circuit operates as an approximation and in steps to obtain a voltage that is the product of two input voltages, any desired degree of accuracy can be obtained with the proper number of increments and adjustment of parameters. (AEC)

Trigger Circuit.

DTIC Science & Technology

A wire of Nitinol can be stretched up to a given amount and will remain in this stretched state until heated to a critical temperature. When heated...circuit of this invention provides a current pulse for the required time period to heat the Nitinol wire to its critical temperature to thereby restore the...wire to its original length. The circuit includes a high power transistor which is gated on for a controlled time to provide the required power to heat the Nitinol wire to its critical temperature. (Author)

High voltage MOSFET switching circuit

DOEpatents

McEwan, T.E.

1994-07-26

The problem of source lead inductance in a MOSFET switching circuit is compensated for by adding an inductor to the gate circuit. The gate circuit inductor produces an inductive spike which counters the source lead inductive drop to produce a rectangular drive voltage waveform at the internal gate-source terminals of the MOSFET. 2 figs.

[Distribution features of chlorophyll a and primary productivity in high frequency area of red tide in East China Sea during spring].

PubMed

Zhou, Weihua; Huo, Wenyi; Yuan, Xiangcheng; Yin, Kedong

2003-07-01

The distributions of chlorophyll a and primary productivity were determined during April to May 2002 in the East China Sea. The results showed that the average concentration of chlorophyll a was 1.086 mg.m-3 at surface layer, and that nano- and pico-phytoplankton (< 20 microns) dominated the phytoplankton biomass in this sea region during Spring (up to 64% of total chlorophyll a content). Ultra-phytoplankton (< 5 microns) consisted 27% of total phytoplankton biomass. Nutrients and feeding pressure of zooplankton affected the distribution of chlorophyll a and its size-fractionation. The average primary productivity was 10.091 mg.m-3.h-1, while that of red tide tracking stations R-03, RL-01 and RG-01 was 399.984 mg.m-3.h-1. Light and nutrients were the main factors affecting the distributions of chlorophyll a and primary productivity. The station DC-11 had a high concentration of phytoplankton biomass. The surface layer concentration of chlorophyll a and primary productivity were up to 9,082 mg.m-3 and 128,79 mg.m-3.h-1, respectively, but the color of the seawater was normal.

49 CFR 234.269 - Cut-out circuits.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Cut-out circuits. 234.269 Section 234.269..., Inspection, and Testing Inspections and Tests § 234.269 Cut-out circuits. Each cut-out circuit shall be... of this section, a cut-out circuit is any circuit which overrides the operation of automatic warning...

49 CFR 234.269 - Cut-out circuits.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Cut-out circuits. 234.269 Section 234.269..., Inspection, and Testing Inspections and Tests § 234.269 Cut-out circuits. Each cut-out circuit shall be... of this section, a cut-out circuit is any circuit which overrides the operation of automatic warning...

Tunable circuit for tunable capacitor devices

DOEpatents

Rivkina, Tatiana; Ginley, David S.

2006-09-19

A tunable circuit (10) for a capacitively tunable capacitor device (12) is provided. The tunable circuit (10) comprises a tunable circuit element (14) and a non-tunable dielectric element (16) coupled to the tunable circuit element (16). A tunable capacitor device (12) and a method for increasing the figure of merit in a tunable capacitor device (12) are also provided.

SENARIET, A Programme To Solve Transient Flows Of Liquids In Complex Circuits

NASA Astrophysics Data System (ADS)

Vargas-Munoz, M.; Rodriguez-Fernandez, M.; Perena-Tapiador, A.

2011-05-01

SENARIET is a programme to study fluid transients in pipeline systems in order to obtain pressure and velocity distributions along a circuit. When a transient process occurs in periods of the same order of the pressure waves’ travelling time along a circuit (the order of the circuit length divided by the effective propagation speed), the compressibility effects in liquids have to be considered. Taking this effect into account, the appropriate equations of continuity and momentum are solved by the method of characteristics, to obtain pressure and velocity along pipes as a function of time. The simulated results have been compared to theoretical and experimental ones to validate and evaluate the precision of the software. The results help to perform efficient and accurate predictions in order to define the propulsion sub-system. This type of analysis is very important in order to evaluate the water hammer effects in propulsion systems used on spacecrafts and launchers.

DIFFERENTIAL FAULT SENSING CIRCUIT

DOEpatents

Roberts, J.H.

1961-09-01

A differential fault sensing circuit is designed for detecting arcing in high-voltage vacuum tubes arranged in parallel. A circuit is provided which senses differences in voltages appearing between corresponding elements likely to fault. Sensitivity of the circuit is adjusted to some level above which arcing will cause detectable differences in voltage. For particular corresponding elements, a group of pulse transformers are connected in parallel with diodes connected across the secondaries thereof so that only voltage excursions are transmitted to a thyratron which is biased to the sensitivity level mentioned.

Gallium Arsenide Domino Circuit

NASA Technical Reports Server (NTRS)

Yang, Long; Long, Stephen I.

1990-01-01

Advantages include reduced power and high speed. Experimental gallium arsenide field-effect-transistor (FET) domino circuit replicated in large numbers for use in dynamic-logic systems. Name of circuit denotes mode of operation, which logic signals propagate from each stage to next when successive stages operated at slightly staggered clock cycles, in manner reminiscent of dominoes falling in a row. Building block of domino circuit includes input, inverter, and level-shifting substages. Combinational logic executed in input substage. During low half of clock cycle, result of logic operation transmitted to following stage.

30 CFR 77.803-1 - Fail safe ground check circuits; maximum voltage.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Fail safe ground check circuits; maximum voltage. 77.803-1 Section 77.803-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF... OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.803-1 Fail safe ground check...

30 CFR 77.803-1 - Fail safe ground check circuits; maximum voltage.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Fail safe ground check circuits; maximum voltage. 77.803-1 Section 77.803-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF... OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.803-1 Fail safe ground check...

30 CFR 77.803-1 - Fail safe ground check circuits; maximum voltage.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Fail safe ground check circuits; maximum voltage. 77.803-1 Section 77.803-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF... OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.803-1 Fail safe ground check...

Probabilistic switching circuits in DNA

PubMed Central

Wilhelm, Daniel; Bruck, Jehoshua

2018-01-01

A natural feature of molecular systems is their inherent stochastic behavior. A fundamental challenge related to the programming of molecular information processing systems is to develop a circuit architecture that controls the stochastic states of individual molecular events. Here we present a systematic implementation of probabilistic switching circuits, using DNA strand displacement reactions. Exploiting the intrinsic stochasticity of molecular interactions, we developed a simple, unbiased DNA switch: An input signal strand binds to the switch and releases an output signal strand with probability one-half. Using this unbiased switch as a molecular building block, we designed DNA circuits that convert an input signal to an output signal with any desired probability. Further, this probability can be switched between 2n different values by simply varying the presence or absence of n distinct DNA molecules. We demonstrated several DNA circuits that have multiple layers and feedback, including a circuit that converts an input strand to an output strand with eight different probabilities, controlled by the combination of three DNA molecules. These circuits combine the advantages of digital and analog computation: They allow a small number of distinct input molecules to control a diverse signal range of output molecules, while keeping the inputs robust to noise and the outputs at precise values. Moreover, arbitrarily complex circuit behaviors can be implemented with just a single type of molecular building block. PMID:29339484

Mems: Platform for Large-Scale Integrated Vacuum Electronic Circuits

DTIC Science & Technology

2017-03-20

SECURITY CLASSIFICATION OF: The objective of the LIVEC advanced study project was to develop a platform for large-scale integrated vacuum electronic ...Distribution Unlimited UU UU UU UU 20-03-2017 1-Jul-2014 30-Jun-2015 Final Report: MEMS Platform for Large-Scale Integrated Vacuum Electronic ... Electronic Circuits (LIVEC) Contract No: W911NF-14-C-0093 COR Dr. James Harvey U.S. ARO RTP, NC 27709-2211 Phone: 702-696-2533 e-mail

Driver circuit for solid state light sources

DOEpatents

Palmer, Fred; Denvir, Kerry; Allen, Steven

2016-02-16

A driver circuit for a light source including one or more solid state light sources, a luminaire including the same, and a method of so driving the solid state light sources are provided. The driver circuit includes a rectifier circuit that receives an alternating current (AC) input voltage and provides a rectified AC voltage. The driver circuit also includes a switching converter circuit coupled to the light source. The switching converter circuit provides a direct current (DC) output to the light source in response to the rectified AC voltage. The driver circuit also includes a mixing circuit, coupled to the light source, to switch current through at least one solid state light source of the light source in response to each of a plurality of consecutive half-waves of the rectified AC voltage.

Quantum mechanical settings inspired by RLC circuits

NASA Astrophysics Data System (ADS)

Alicata, G.; Bagarello, F.; Gargano, F.; Spagnolo, S.

2018-04-01

In some recent papers, several authors used electronic circuits to construct loss and gain systems. This is particularly interesting in the context of PT-quantum mechanics, where this kind of effects appears quite naturally. The electronic circuits used so far are simple, but not so much. Surprisingly enough, a rather trivial RLC circuit can be analyzed with the same perspective and it produces a variety of unexpected results, both from a mathematical and on a physical side. In this paper, we show that this circuit produces two biorthogonal bases associated with the Liouville matrix L used in the treatment of its dynamics, with a biorthogonality which is linked to the value of the parameters of the circuit. We also show that the related loss RLC circuit is naturally associated with a gain RLC circuit and that the relation between the two is rather naturally encoded in L . We propose a pseudo-fermionic analysis of the circuit, and we introduce the notion of m-equivalence between electronic circuits.

Dopamine-Modulated Recurrent Corticoefferent Feedback in Primary Sensory Cortex Promotes Detection of Behaviorally Relevant Stimuli

PubMed Central

Handschuh, Juliane

2014-01-01

Dopaminergic neurotransmission in primary auditory cortex (AI) has been shown to be involved in learning and memory functions. Moreover, dopaminergic projections and D1/D5 receptor distributions display a layer-dependent organization, suggesting specific functions in the cortical circuitry. However, the circuit effects of dopaminergic neurotransmission in sensory cortex and their possible roles in perception, learning, and memory are largely unknown. Here, we investigated layer-specific circuit effects of dopaminergic neuromodulation using current source density (CSD) analysis in AI of Mongolian gerbils. Pharmacological stimulation of D1/D5 receptors increased auditory-evoked synaptic currents in infragranular layers, prolonging local thalamocortical input via positive feedback between infragranular output and granular input. Subsequently, dopamine promoted sustained cortical activation by prolonged recruitment of long-range corticocortical networks. A detailed circuit analysis combining layer-specific intracortical microstimulation (ICMS), CSD analysis, and pharmacological cortical silencing revealed that cross-laminar feedback enhanced by dopamine relied on a positive, fast-acting recurrent corticoefferent loop, most likely relayed via local thalamic circuits. Behavioral signal detection analysis further showed that activation of corticoefferent output by infragranular ICMS, which mimicked auditory activation under dopaminergic influence, was most effective in eliciting a behaviorally detectable signal. Our results show that D1/D5-mediated dopaminergic modulation in sensory cortex regulates positive recurrent corticoefferent feedback, which enhances states of high, persistent activity in sensory cortex evoked by behaviorally relevant stimuli. In boosting horizontal network interactions, this potentially promotes the readout of task-related information from cortical synapses and improves behavioral stimulus detection. PMID:24453315

Power system with an integrated lubrication circuit

DOEpatents

Hoff, Brian D [East Peoria, IL; Akasam, Sivaprasad [Peoria, IL; Algrain, Marcelo C [Peoria, IL; Johnson, Kris W [Washington, IL; Lane, William H [Chillicothe, IL

2009-11-10

A power system includes an engine having a first lubrication circuit and at least one auxiliary power unit having a second lubrication circuit. The first lubrication circuit is in fluid communication with the second lubrication circuit.

High-precision buffer circuit for suppression of regenerative oscillation

NASA Technical Reports Server (NTRS)

Tripp, John S.; Hare, David A.; Tcheng, Ping

1995-01-01

Precision analog signal conditioning electronics have been developed for wind tunnel model attitude inertial sensors. This application requires low-noise, stable, microvolt-level DC performance and a high-precision buffered output. Capacitive loading of the operational amplifier output stages due to the wind tunnel analog signal distribution facilities caused regenerative oscillation and consequent rectification bias errors. Oscillation suppression techniques commonly used in audio applications were inadequate to maintain the performance requirements for the measurement of attitude for wind tunnel models. Feedback control theory is applied to develop a suppression technique based on a known compensation (snubber) circuit, which provides superior oscillation suppression with high output isolation and preserves the low-noise low-offset performance of the signal conditioning electronics. A practical design technique is developed to select the parameters for the compensation circuit to suppress regenerative oscillation occurring when typical shielded cable loads are driven.

Circuit with a Switch for Charging a Battery in a Battery Capacitor Circuit

NASA Technical Reports Server (NTRS)

Stuart, Thomas A. (Inventor); Ashtiani, Cyrus N. (Inventor)

2008-01-01

A circuit for charging a battery combined with a capacitor includes a power supply adapted to be connected to the capacitor, and the battery. The circuit includes an electronic switch connected to the power supply. The electronic switch is responsive to switch between a conducting state to allow current and a non-conducting state to prevent current flow. The circuit includes a control device connected to the switch and is operable to generate a control signal to continuously switch the electronic switch between the conducting and non-conducting states to charge the battery.

Atypical form of Alzheimer's disease with prominent posterior cortical atrophy: a review of lesion distribution and circuit disconnection in cortical visual pathways

NASA Technical Reports Server (NTRS)

Hof, P. R.; Vogt, B. A.; Bouras, C.; Morrison, J. H.; Bloom, F. E. (Principal Investigator)

1997-01-01

In recent years, the existence of visual variants of Alzheimer's disease characterized by atypical clinical presentation at onset has been increasingly recognized. In many of these cases post-mortem neuropathological assessment revealed that correlations could be established between clinical symptoms and the distribution of neurodegenerative lesions. We have analyzed a series of Alzheimer's disease patients presenting with prominent visual symptomatology as a cardinal sign of the disease. In these cases, a shift in the distribution of pathological lesions was observed such that the primary visual areas and certain visual association areas within the occipito-parieto-temporal junction and posterior cingulate cortex had very high densities of lesions, whereas the prefrontal cortex had fewer lesions than usually observed in Alzheimer's disease. Previous quantitative analyses have demonstrated that in Alzheimer's disease, primary sensory and motor cortical areas are less damaged than the multimodal association areas of the frontal and temporal lobes, as indicated by the laminar and regional distribution patterns of neurofibrillary tangles and senile plaques. The distribution of pathological lesions in the cerebral cortex of Alzheimer's disease cases with visual symptomatology revealed that specific visual association pathways were disrupted, whereas these particular connections are likely to be affected to a less severe degree in the more common form of Alzheimer's disease. These data suggest that in some cases with visual variants of Alzheimer's disease, the neurological symptomatology may be related to the loss of certain components of the cortical visual pathways, as reflected by the particular distribution of the neuropathological markers of the disease.

A Global Circuit Diagram to Contrast the Behavior of the DC and AC Global Circuits

NASA Astrophysics Data System (ADS)

Williams, E.; Boldi, R. A.; Markson, R. J.

2017-12-01

The Earth-ionosphere cavity is home to both the classical DC and the AC (Schumann resonances) global circuits. The predominant source for the AC global circuit is lightning, but the sources for the DC global circuit source remains controversial. Separate measurements over many years have shown that the amplitude variation of global lightning and the AC global circuit is about twice that of the DC global circuit on both the diurnal and annual time scales. A global diagram is used to shed further light on this result and to explore the co-variation of the two global circuits. Actual measurements of the ionospheric potential (Vi) are plotted against the simultaneous global lightning flash rate F. The latter estimates are drawn from a global climatology of LIS/OTD satellite observations (Cecil et al., 2014) giving flash rate as a function of both Day of Year and UT time, and are used as best guesses for F at the time of the Vi observations. A least-squares linear fit through the data points on this diagram show a zero-flash-rate intercept for Vi that is more than half of the mean Vi ( 250 kV). This result suggests that electrified shower clouds (without lightning), possibly supplemented by convective transport of positive space charge in the marine boundary layer, are playing a greater role in driving the DC global circuit than previously suspected.

Demultiplexer circuit for neural stimulation

DOEpatents

Wessendorf, Kurt O; Okandan, Murat; Pearson, Sean

2012-10-09

A demultiplexer circuit is disclosed which can be used with a conventional neural stimulator to extend the number of electrodes which can be activated. The demultiplexer circuit, which is formed on a semiconductor substrate containing a power supply that provides all the dc electrical power for operation of the circuit, includes digital latches that receive and store addressing information from the neural stimulator one bit at a time. This addressing information is used to program one or more 1:2.sup.N demultiplexers in the demultiplexer circuit which then route neural stimulation signals from the neural stimulator to an electrode array which is connected to the outputs of the 1:2.sup.N demultiplexer. The demultiplexer circuit allows the number of individual electrodes in the electrode array to be increased by a factor of 2.sup.N with N generally being in a range of 2-4.

49 CFR 236.731 - Controller, circuit.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Controller, circuit. 236.731 Section 236.731 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Controller, circuit. A device for opening and closing electric circuits. ...

Gas-Sensing Flip-Flop Circuits

NASA Technical Reports Server (NTRS)

Buehler, Martin G.; Blaes, Brent R.; Williams, Roger; Ryan, Margaret A.

1995-01-01

Gas-sensing integrated circuits consisting largely of modified static random-access memories (SRAMs) undergoing development, building on experience gained in use of modified SRAMs as radiation sensors. Each SRAM memory cell includes flip-flop circuit; sensors exploit metastable state that lies between two stable states (corresponding to binary logic states) of flip-flop circuit. Voltages of metastable states vary with exposures of gas-sensitive resistors.

Electronic control circuits: A compilation

NASA Technical Reports Server (NTRS)

1973-01-01

A compilation of technical R and D information on circuits and modular subassemblies is presented as a part of a technology utilization program. Fundamental design principles and applications are given. Electronic control circuits discussed include: anti-noise circuit; ground protection device for bioinstrumentation; temperature compensation for operational amplifiers; hybrid gatling capacitor; automatic signal range control; integrated clock-switching control; and precision voltage tolerance detector.

Faster Evolution of More Multifunctional Logic Circuits

NASA Technical Reports Server (NTRS)

Stoica, Adrian; Zebulum, Ricardo

2005-01-01

A modification in a method of automated evolutionary synthesis of voltage-controlled multifunctional logic circuits makes it possible to synthesize more circuits in less time. Prior to the modification, the computations for synthesizing a four-function logic circuit by this method took about 10 hours. Using the method as modified, it is possible to synthesize a six-function circuit in less than half an hour. The concepts of automated evolutionary synthesis and voltage-controlled multifunctional logic circuits were described in a number of prior NASA Tech Briefs articles. To recapitulate: A circuit is designed to perform one of several different logic functions, depending on the value of an applied control voltage. The circuit design is synthesized following an automated evolutionary approach that is so named because it is modeled partly after the repetitive trial-and-error process of biological evolution. In this process, random populations of integer strings that encode electronic circuits play a role analogous to that of chromosomes. An evolved circuit is tested by computational simulation (prior to testing in real hardware to verify a final design). Then, in a fitness-evaluation step, responses of the circuit are compared with specifications of target responses and circuits are ranked according to how close they come to satisfying specifications. The results of the evaluation provide guidance for refining designs through further iteration.

Understanding in an instant: neurophysiological evidence for mechanistic language circuits in the brain.

PubMed

Pulvermüller, Friedemann; Shtyrov, Yury; Hauk, Olaf

2009-08-01

How long does it take the human mind to grasp the idea when hearing or reading a sentence? Neurophysiological methods looking directly at the time course of brain activity indexes of comprehension are critical for finding the answer to this question. As the dominant cognitive approaches, models of serial/cascaded and parallel processing, make conflicting predictions on the time course of psycholinguistic information access, they can be tested using neurophysiological brain activation recorded in MEG and EEG experiments. Seriality and cascading of lexical, semantic and syntactic processes receives support from late (latency approximately 1/2s) sequential neurophysiological responses, especially N400 and P600. However, parallelism is substantiated by early near-simultaneous brain indexes of a range of psycholinguistic processes, up to the level of semantic access and context integration, emerging already 100-250ms after critical stimulus information is present. Crucially, however, there are reliable latency differences of 20-50ms between early cortical area activations reflecting lexical, semantic and syntactic processes, which are left unexplained by current serial and parallel brain models of language. We here offer a mechanistic model grounded in cortical nerve cell circuits that builds upon neuroanatomical and neurophysiological knowledge and explains both near-simultaneous activations and fine-grained delays. A key concept is that of discrete distributed cortical circuits with specific inter-area topographies. The full activation, or ignition, of specifically distributed binding circuits explains the near-simultaneity of early neurophysiological indexes of lexical, syntactic and semantic processing. Activity spreading within circuits determined by between-area conduction delays accounts for comprehension-related regional activation differences in the millisecond range.

An Experience of Teaching for Learning by Observation: Remote-Controlled Experiments on Electrical Circuits

ERIC Educational Resources Information Center

Kong, Siu Cheung; Yeung, Yau Yuen; Wu, Xian Qiu

2009-01-01

In order to facilitate senior primary school students in Hong Kong to engage in learning by observation of the phenomena related to electrical circuits, a design of a specific courseware system, of which the interactive human-machine interface was created with the use of an open-source software called the LabVNC, for conducting online…

A Fault Location Algorithm for Two-End Series-Compensated Double-Circuit Transmission Lines Using the Distributed Parameter Line Model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kang, Ning; Gombos, Gergely; Mousavi, Mirrasoul J.

A new fault location algorithm for two-end series-compensated double-circuit transmission lines utilizing unsynchronized two-terminal current phasors and local voltage phasors is presented in this paper. The distributed parameter line model is adopted to take into account the shunt capacitance of the lines. The mutual coupling between the parallel lines in the zero-sequence network is also considered. The boundary conditions under different fault types are used to derive the fault location formulation. The developed algorithm directly uses the local voltage phasors on the line side of series compensation (SC) and metal oxide varistor (MOV). However, when potential transformers are not installedmore » on the line side of SC and MOVs for the local terminal, these measurements can be calculated from the local terminal bus voltage and currents by estimating the voltages across the SC and MOVs. MATLAB SimPowerSystems is used to generate cases under diverse fault conditions to evaluating accuracy. The simulation results show that the proposed algorithm is qualified for practical implementation.« less

Bio-inspired feedback-circuit implementation of discrete, free energy optimizing, winner-take-all computations.

PubMed

Genewein, Tim; Braun, Daniel A

2016-06-01

Bayesian inference and bounded rational decision-making require the accumulation of evidence or utility, respectively, to transform a prior belief or strategy into a posterior probability distribution over hypotheses or actions. Crucially, this process cannot be simply realized by independent integrators, since the different hypotheses and actions also compete with each other. In continuous time, this competitive integration process can be described by a special case of the replicator equation. Here we investigate simple analog electric circuits that implement the underlying differential equation under the constraint that we only permit a limited set of building blocks that we regard as biologically interpretable, such as capacitors, resistors, voltage-dependent conductances and voltage- or current-controlled current and voltage sources. The appeal of these circuits is that they intrinsically perform normalization without requiring an explicit divisive normalization. However, even in idealized simulations, we find that these circuits are very sensitive to internal noise as they accumulate error over time. We discuss in how far neural circuits could implement these operations that might provide a generic competitive principle underlying both perception and action.

49 CFR 236.786 - Principle, closed circuit.

Code of Federal Regulations, 2010 CFR

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...

49 CFR 236.725 - Circuit, switch shunting.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 4 2013-10-01 2013-10-01 false Circuit, switch shunting. 236.725 Section 236.725 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, switch shunting. A shunting circuit which is closed through contacts of a switch circuit...

49 CFR 236.725 - Circuit, switch shunting.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Circuit, switch shunting. 236.725 Section 236.725 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, switch shunting. A shunting circuit which is closed through contacts of a switch circuit...

49 CFR 236.725 - Circuit, switch shunting.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, switch shunting. 236.725 Section 236.725 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, switch shunting. A shunting circuit which is closed through contacts of a switch circuit...

49 CFR 236.725 - Circuit, switch shunting.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 4 2014-10-01 2014-10-01 false Circuit, switch shunting. 236.725 Section 236.725 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, switch shunting. A shunting circuit which is closed through contacts of a switch circuit...

49 CFR 236.725 - Circuit, switch shunting.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 4 2012-10-01 2012-10-01 false Circuit, switch shunting. 236.725 Section 236.725 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, switch shunting. A shunting circuit which is closed through contacts of a switch circuit...

Protective circuit for thyristor controlled systems and thyristor converter embodying such protective circuit

DOEpatents

Downhower, Jr., Francis H.; Finlayson, Paul T.

1984-04-10

A snubber circuit coupled across each thyristor to be gated in a chain of thyristors determines the critical output of a NOR LATCH whenever one snubber circuit could not be charged and discharged under normal gating conditions because of a short failure.

Four-terminal circuit element with photonic core

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sampayan, Stephen

A four-terminal circuit element is described that includes a photonic core inside of the circuit element that uses a wide bandgap semiconductor material that exhibits photoconductivity and allows current flow through the material in response to the light that is incident on the wide bandgap material. The four-terminal circuit element can be configured based on various hardware structures using a single piece or multiple pieces or layers of a wide bandgap semiconductor material to achieve various designed electrical properties such as high switching voltages by using the photoconductive feature beyond the breakdown voltages of semiconductor devices or circuits operated basedmore » on electrical bias or control designs. The photonic core aspect of the four-terminal circuit element provides unique features that enable versatile circuit applications to either replace the semiconductor transistor-based circuit elements or semiconductor diode-based circuit elements.« less

Noise isolation system for high-speed circuits

DOEpatents

McNeilly, D.R.

1983-12-29

A noise isolation circuit is provided that consists of a dual function bypass which confines high-speed switching noise to the component or circuit which generates it and isolates the component or circuit from high-frequency noise transients which may be present on the ground and power supply busses. A local circuit ground is provided which is coupled to the system ground by sufficient impedance to force the dissipation of the noise signal in the local circuit or component generating the noise. The dual function bypass network couples high-frequency noise signals generated in the local component or circuit through a capacitor to the local ground while isolating the component or circuit from noise signals which may be present on the power supply busses or system ground. The network is an effective noise isolating system and is applicable to both high-speed analog and digital circuits.

Noise isolation system for high-speed circuits

DOEpatents

McNeilly, David R.

1986-01-01

A noise isolation circuit is provided that consists of a dual function bypass which confines high-speed switching noise to the component or circuit which generates it and isolates the component or circuit from high-frequency noise transients which may be present on the ground and power supply busses. A local circuit ground is provided which is coupled to the system ground by sufficient impedance to force the dissipation of the noise signal in the local circuit or component generating the noise. The dual function bypass network couples high-frequency noise signals generated in the local component or circuit through a capacitor to the local ground while isolating the component or circuit from noise signals which may be present on the power supply busses or system ground. The network is an effective noise isolating system and is applicable to both high-speed analog and digital circuits.

Sequential Polarity-Reversing Circuit

NASA Technical Reports Server (NTRS)

Labaw, Clayton C.

1994-01-01

Proposed circuit reverses polarity of electric power supplied to bidirectional dc motor, reversible electro-mechanical actuator, or other device operating in direction depending on polarity. Circuit reverses polarity each time power turned on, without need for additional polarity-reversing or direction signals and circuitry to process them.

The plastic scintillator detector calibration circuit for DAMPE

NASA Astrophysics Data System (ADS)

Yang, Haibo; Kong, Jie; Zhao, Hongyun; Su, Hong

2016-07-01

The Dark Matter Particle Explorer (DAMPE) is being constructed as a scientific satellite to observe high energy cosmic rays in space. Plastic scintillator detector array (PSD), developed by Institute of Modern Physics, Chinese Academy of Sciences (IMPCAS), is one of the most important parts in the payload of DAMPE which is mainly used for the study of dark matter. As an anti-coincidence detector, and a charged-particle identification detector, the PSD has a total of 360 electronic readout channels, which are distributed at four sides of PSD using four identical front end electronics (FEE). Each FEE reads out 90 charge signals output by the detector. A special calibration circuit is designed in FEE. FPGA is used for on-line control, enabling the calibration circuit to generate the pulse signal with known charge. The generated signal is then sent to the FEE for calibration and self-test. This circuit mainly consists of DAC, operation amplifier, analog switch, capacitance and resistance. By using controllable step pulse, the charge can be coupled to the charge measuring chip using the small capacitance. In order to fulfill the system's objective of large dynamic range, the FEE is required to have good linearity. Thus, the charge-controllable signal is needed to do sweep test on all channels in order to obtain the non-linear parameters for off-line correction. On the other hand, the FEE will run on the satellite for three years. The changes of the operational environment and the aging of devices will lead to parameter variation of the FEE, highlighting the need for regular calibration. The calibration signal generation circuit also has a compact structure and the ability to work normally, with the PSD system's voltage resolution being higher than 0.6%.

Pharmacokinetics and RC Circuit Concepts

NASA Astrophysics Data System (ADS)

Cock, Mieke De; Janssen, Paul

2013-11-01

Most introductory physics courses include a chapter on RC circuits in which the differential equations for the charging and discharging of a capacitor are derived. A number of papers in this journal describe lab experiments dealing with the measurement of different parameters in such RC circuits. In this contribution, we report on a lab experiment we developed for students majoring in pharmacy, using RC circuits to simulate a pharmacokinetic process.

Computer-aided linear-circuit design.

NASA Technical Reports Server (NTRS)

Penfield, P.

1971-01-01

Usually computer-aided design (CAD) refers to programs that analyze circuits conceived by the circuit designer. Among the services such programs should perform are direct network synthesis, analysis, optimization of network parameters, formatting, storage of miscellaneous data, and related calculations. The program should be embedded in a general-purpose conversational language such as BASIC, JOSS, or APL. Such a program is MARTHA, a general-purpose linear-circuit analyzer embedded in APL.

ELECTRONIC TRIGGER CIRCUIT

DOEpatents

Russell, J.A.G.

1958-01-01

An electronic trigger circuit is described of the type where an output pulse is obtained only after an input voltage has cqualed or exceeded a selected reference voltage. In general, the invention comprises a source of direct current reference voltage in series with an impedance and a diode rectifying element. An input pulse of preselected amplitude causes the diode to conduct and develop a signal across the impedance. The signal is delivered to an amplifier where an output pulse is produced and part of the output is fed back in a positive manner to the diode so that the amplifier produces a steep wave front trigger pulsc at the output. The trigger point of the described circuit is not subject to variation due to the aging, etc., of multi-electrode tabes, since the diode circuit essentially determines the trigger point.

A continuously pulsed copper halide laser with a cable-capacitor Blumlein discharge circuit

NASA Technical Reports Server (NTRS)

Nerheim, N. M.; Bhanji, A. M.; Russell, G. R.

1978-01-01

Experimental characteristics of a continuously pulsed copper halide laser with a cable-capacitor Blumlein discharge circuit are reported. Quartz laser tubes 1 m in length and 1.5 and 2.5 cm in diameter were employed to study the effects of the electrical circuit, lasant, and buffer gas on laser performance. Measured properties of the Blumlein circuit are compared with an analytic solution for an idealized circuit. Both CuCl and CuBr with neon and helium buffer gas were studied. A maximum average power of 12.5 W was obtained with a 1.5 nF capacitor charged to 8 kV and discharged at 31 kHz with CuCl and neon buffer gas at 0.7 kPa in a 2.5-cm-diam tube. A maximum efficiency of 0.72 percent was obtained at 9 W average power. Measurements of the radial distribution of the power in the laser beam and the variation of laser power at 510.6 and 578.2 nm with halide vapor density are also reported. Double and continuously pulsed laser characteristics are compared, and the role of copper metastable level atoms in limiting the laser pulse energy density is discussed.

The sensitivities of in cloud and cloud top phase distributions to primary ice formation in ICON-LEM

NASA Astrophysics Data System (ADS)

Beydoun, H.; Karrer, M.; Tonttila, J.; Hoose, C.

2017-12-01

Mixed phase clouds remain a leading source of uncertainty in our attempt to quantify cloud-climate and aerosol-cloud climate interactions. Nevertheless, recent advances in parametrizing the primary ice formation process, high resolution cloud modelling, and retrievals of cloud phase distributions from satellite data offer an excellent opportunity to conduct closure studies on the sensitivity of the cloud phase to microphysical and dynamical processes. Particularly, the reliability of satellite data to resolve the phase at the top of the cloud provides a promising benchmark to compare model output to. We run large eddy simulations with the new ICOsahedral Non-hydrostatic atmosphere model (ICON) to place bounds on the sensitivity of in cloud and cloud top phase to the primary ice formation process. State of the art primary ice formation parametrizations in the form of the cumulative ice active site density ns are implemented in idealized deep convective cloud simulations. We exploit the ability of ICON-LEM to switch between a two moment microphysics scheme and the newly developed Predicted Particle Properties (P3) scheme by running our simulations in both configurations for comparison. To quantify the sensitivity of cloud phase to primary ice formation, cloud ice content is evaluated against order of magnitude changes in ns at variable convective strengths. Furthermore, we assess differences between in cloud and cloud top phase distributions as well as the potential impact of updraft velocity on the suppression of the Wegener-Bergeron-Findeisen process. The study aims to evaluate our practical understanding of primary ice formation in the context of predicting the structure and evolution of mixed phase clouds.

49 CFR 236.726 - Circuit, track.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, track. 236.726 Section 236.726 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, track. An electrical circuit of which the rails of the track form a part. ...

49 CFR 234.203 - Control circuits.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Control circuits. 234.203 Section 234.203 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION..., Inspection, and Testing Maintenance Standards § 234.203 Control circuits. All control circuits that affect...

49 CFR 234.203 - Control circuits.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Control circuits. 234.203 Section 234.203 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION..., Inspection, and Testing Maintenance Standards § 234.203 Control circuits. All control circuits that affect...

Short circuit in deep brain stimulation.

PubMed

Samura, Kazuhiro; Miyagi, Yasushi; Okamoto, Tsuyoshi; Hayami, Takehito; Kishimoto, Junji; Katano, Mitsuo; Kamikaseda, Kazufumi

2012-11-01

The authors undertook this study to investigate the incidence, cause, and clinical influence of short circuits in patients treated with deep brain stimulation (DBS). After the incidental identification of a short circuit during routine follow-up, the authors initiated a policy at their institution of routinely evaluating both therapeutic impedance and system impendence at every outpatient DBS follow-up visit, irrespective of the presence of symptoms suggesting possible system malfunction. This study represents a report of their findings after 1 year of this policy. Implanted DBS leads exhibiting short circuits were identified in 7 patients (8.9% of the patients seen for outpatient follow-up examinations during the 12-month study period). The mean duration from DBS lead implantation to the discovery of the short circuit was 64.7 months. The symptoms revealing short circuits included the wearing off of therapeutic effect, apraxia of eyelid opening, or dysarthria in 6 patients with Parkinson disease (PD), and dystonia deterioration in 1 patient with generalized dystonia. All DBS leads with short circuits had been anchored to the cranium using titanium miniplates. Altering electrode settings resulted in clinical improvement in the 2 PD cases in which patients had specific symptoms of short circuits (2.5%) but not in the other 4 cases. The patient with dystonia underwent repositioning and replacement of a lead because the previous lead was located too anteriorly, but did not experience symptom improvement. In contrast to the sudden loss of clinical efficacy of DBS caused by an open circuit, short circuits may arise due to a gradual decrease in impedance, causing the insidious development of neurological symptoms via limited or extended potential fields as well as shortened battery longevity. The incidence of short circuits in DBS may be higher than previously thought, especially in cases in which DBS leads are anchored with miniplates. The circuit impedance of DBS

MULTI-ELECTRODE TUBE PULSE MEMORY CIRCUIT

DOEpatents

Gundlach, J.C.; Reeves, J.B.

1958-05-20

Control circuits are described for pulse memory devices for scalers and the like, and more particularly to a driving or energizing circuit for a polycathode gaseous discharge tube having an elongated anode and a successive series of cathodes spaced opposite the anode along its length. The circuit is so arranged as to utilize an arc discharge between the anode and a cathode to count a series of pulses. Upon application of an input pulse the discharge is made to occur between the anode and the next successive cathode, and an output pulse is produced when a particular subsequent cathode is reached. The circuit means for transfering the discharge by altering the anode potential and potential of the cathodes and interconnecting the cathodes constitutes the novel aspects of the invention. A low response time and reduced number of circuit components are the practical advantages of the described circuit.

Another Nulling Hall-Effect Current-Measuring Circuit

NASA Technical Reports Server (NTRS)

Thibodeau, Phillip E.; Sullender, Craig C.

1993-01-01

Lightweight, low-power circuit provides noncontact measurement of alternating or direct current of many ampheres in main conductor. Advantages of circuit over other nulling Hall-effect current-measuring circuits is stability and accuracy increased by putting both analog-to-digital and digital-to-analog converters in nulling feedback loop. Converters and rest of circuit designed for operation at sampling rate of 100 kHz, but rate changed to alter time or frequency response of circuit.

A Virtual Circuits Lab

ERIC Educational Resources Information Center

Vick, Matthew E.

2010-01-01

The University of Colorado's Physics Education Technology (PhET) website offers free, high-quality simulations of many physics experiments that can be used in the classroom. The Circuit Construction Kit, for example, allows students to safely and constructively play with circuit components while learning the mathematics behind many circuit…

47 CFR 32.2232 - Circuit equipment.

Code of Federal Regulations, 2011 CFR

2011-10-01

... subaccount 2232.1 Electronic shall include the original cost of electronic circuit equipment. (c) This... 47 Telecommunication 2 2011-10-01 2011-10-01 false Circuit equipment. 32.2232 Section 32.2232... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2232 Circuit equipment...

47 CFR 32.2232 - Circuit equipment.

Code of Federal Regulations, 2012 CFR

2012-10-01

... subaccount 2232.1 Electronic shall include the original cost of electronic circuit equipment. (c) This... 47 Telecommunication 2 2012-10-01 2012-10-01 false Circuit equipment. 32.2232 Section 32.2232... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2232 Circuit equipment...

47 CFR 32.2232 - Circuit equipment.

Code of Federal Regulations, 2010 CFR

2010-10-01

... subaccount 2232.1 Electronic shall include the original cost of electronic circuit equipment. (c) This... 47 Telecommunication 2 2010-10-01 2010-10-01 false Circuit equipment. 32.2232 Section 32.2232... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2232 Circuit equipment...

47 CFR 32.2232 - Circuit equipment.

Code of Federal Regulations, 2013 CFR

2013-10-01

... subaccount 2232.1 Electronic shall include the original cost of electronic circuit equipment. (c) This... 47 Telecommunication 2 2013-10-01 2013-10-01 false Circuit equipment. 32.2232 Section 32.2232... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2232 Circuit equipment...

47 CFR 32.2232 - Circuit equipment.

Code of Federal Regulations, 2014 CFR

2014-10-01

... subaccount 2232.1 Electronic shall include the original cost of electronic circuit equipment. (c) This... 47 Telecommunication 2 2014-10-01 2014-10-01 false Circuit equipment. 32.2232 Section 32.2232... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2232 Circuit equipment...

Operator Spreading in Random Unitary Circuits

NASA Astrophysics Data System (ADS)

Nahum, Adam; Vijay, Sagar; Haah, Jeongwan

2018-04-01

Random quantum circuits yield minimally structured models for chaotic quantum dynamics, which are able to capture, for example, universal properties of entanglement growth. We provide exact results and coarse-grained models for the spreading of operators by quantum circuits made of Haar-random unitaries. We study both 1 +1 D and higher dimensions and argue that the coarse-grained pictures carry over to operator spreading in generic many-body systems. In 1 +1 D , we demonstrate that the out-of-time-order correlator (OTOC) satisfies a biased diffusion equation, which gives exact results for the spatial profile of the OTOC and determines the butterfly speed vB. We find that in 1 +1 D , the "front" of the OTOC broadens diffusively, with a width scaling in time as t1 /2. We address fluctuations in the OTOC between different realizations of the random circuit, arguing that they are negligible in comparison to the broadening of the front within a realization. Turning to higher dimensions, we show that the averaged OTOC can be understood exactly via a remarkable correspondence with a purely classical droplet growth problem. This implies that the width of the front of the averaged OTOC scales as t1 /3 in 2 +1 D and as t0.240 in 3 +1 D (exponents of the Kardar-Parisi-Zhang universality class). We support our analytic argument with simulations in 2 +1 D . We point out that, in two or higher spatial dimensions, the shape of the spreading operator at late times is affected by underlying lattice symmetries and, in general, is not spherical. However, when full spatial rotational symmetry is present in 2 +1 D , our mapping implies an exact asymptotic form for the OTOC, in terms of the Tracy-Widom distribution. For an alternative perspective on the OTOC in 1 +1 D , we map it to the partition function of an Ising-like statistical mechanics model. As a result of special structure arising from unitarity, this partition function reduces to a random walk calculation which can be

A synthetic mammalian electro-genetic transcription circuit.

PubMed

Weber, Wilfried; Luzi, Stefan; Karlsson, Maria; Sanchez-Bustamante, Carlota Diaz; Frey, Urs; Hierlemann, Andreas; Fussenegger, Martin

2009-03-01

Electric signal processing has evolved to manage rapid information transfer in neuronal networks and muscular contraction in multicellular organisms and controls the most sophisticated man-built devices. Using a synthetic biology approach to assemble electronic parts with genetic control units engineered into mammalian cells, we designed an electric power-adjustable transcription control circuit able to integrate the intensity of a direct current over time, to translate the amplitude or frequency of an alternating current into an adjustable genetic readout or to modulate the beating frequency of primary heart cells. Successful miniaturization of the electro-genetic devices may pave the way for the design of novel hybrid electro-genetic implants assembled from electronic and genetic parts.

A synthetic mammalian electro-genetic transcription circuit

PubMed Central

Weber, Wilfried; Luzi, Stefan; Karlsson, Maria; Sanchez-Bustamante, Carlota Diaz; Frey, Urs; Hierlemann, Andreas; Fussenegger, Martin

2009-01-01

Electric signal processing has evolved to manage rapid information transfer in neuronal networks and muscular contraction in multicellular organisms and controls the most sophisticated man-built devices. Using a synthetic biology approach to assemble electronic parts with genetic control units engineered into mammalian cells, we designed an electric power-adjustable transcription control circuit able to integrate the intensity of a direct current over time, to translate the amplitude or frequency of an alternating current into an adjustable genetic readout or to modulate the beating frequency of primary heart cells. Successful miniaturization of the electro-genetic devices may pave the way for the design of novel hybrid electro-genetic implants assembled from electronic and genetic parts. PMID:19190091

Automated Sneak Circuit Analysis Technique

DTIC Science & Technology

1990-06-01

the OrCAD/SDT module Port facility. 2. The terminals of all in- circuit voltage sources (e , batteries) must be labeled using the OrCAD/SDT module port...ELECTE 1 MAY 2 01994 _- AUTOMATED SNEAK CIRCUIT ANALYSIS TECHNIQUEIt~ w I wtA who RADC 94-14062 Systems Reliability & Engineering Division Rome...Air Develpment Center Best Avai~lable copy AUTOMATED SNEAK CIRCUIT ANALYSIS TECHNIQUE RADC June 1990 Systems Reliability & Engineering Division Rome Air

Chattanooga Electric Power Board Case Study Distribution Automation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Glass, Jim; Melin, Alexander M.; Starke, Michael R.

In 2009, the U.S. Department of Energy under the American Recovery and Reinvestment Act (ARRA) awarded a grant to the Chattanooga, Tennessee, Electric Power Board (EPB) as part of the Smart Grid Investment Grant Program. The grant had the objective “to accelerate the transformation of the nation’s electric grid by deploying smart grid technologies.” This funding award enabled EPB to expedite the original smart grid implementation schedule from an estimated 10-12 years to 2.5 years. With this funding, EPB invested heavily in distribution automation technologies including installing over 1,200 automated circuit switches and sensors on 171 circuits. For utilities consideringmore » a commitment to distribution automation, there are underlying questions such as the following: “What is the value?” and “What are the costs?” This case study attempts to answer these questions. The primary benefit of distribution automation is increased reliability or reduced power outage duration and frequency. Power outages directly impact customer economics by interfering with business functions. In the past, this economic driver has been difficult to effectively evaluate. However, as this case study demonstrates, tools and analysis techniques are now available. In this case study, the impact on customer costs associated with power outages before and after the implementation of distribution automation are compared. Two example evaluations are performed to demonstrate the benefits: 1) a savings baseline for customers under normal operations1 and 2) customer savings for a single severe weather event. Cost calculations for customer power outages are performed using the US Department of Energy (DOE) Interruption Cost Estimate (ICE) calculator2. This tool uses standard metrics associated with outages and the customers to calculate cost impact. The analysis shows that EPB customers have seen significant reliability improvements from the implementation of distribution automation

Illuminating Neural Circuits: From Molecules to MRI.

PubMed

Lee, Jin Hyung; Kreitzer, Anatol C; Singer, Annabelle C; Schiff, Nicholas D

2017-11-08

Neurological disease drives symptoms through pathological changes to circuit functions. Therefore, understanding circuit mechanisms that drive behavioral dysfunction is of critical importance for quantitative diagnosis and systematic treatment of neurological disease. Here, we describe key technologies that enable measurement and manipulation of neural activity and neural circuits. Applying these approaches led to the discovery of circuit mechanisms underlying pathological motor behavior, arousal regulation, and protein accumulation. Finally, we discuss how optogenetic functional magnetic resonance imaging reveals global scale circuit mechanisms, and how circuit manipulations could lead to new treatments of neurological diseases. Copyright © 2017 the authors 0270-6474/17/3710817-09$15.00/0.

30 CFR 75.1323 - Blasting circuits.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) Blasting circuits shall be protected from sources of stray electric current. (b) Detonators made by...) Each wire connection in a blasting circuit shall be— (1) Properly spliced; and (2) Separated from other connections in the circuit to prevent accidental contact and arcing. (h) Uninsulated connections in each...

30 CFR 75.1323 - Blasting circuits.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) Blasting circuits shall be protected from sources of stray electric current. (b) Detonators made by...) Each wire connection in a blasting circuit shall be— (1) Properly spliced; and (2) Separated from other connections in the circuit to prevent accidental contact and arcing. (h) Uninsulated connections in each...

49 CFR 234.203 - Control circuits.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 4 2013-10-01 2013-10-01 false Control circuits. 234.203 Section 234.203... EMERGENCY NOTIFICATION SYSTEMS Maintenance, Inspection, and Testing Maintenance Standards § 234.203 Control circuits. All control circuits that affect the safe operation of a highway-rail grade crossing warning...

49 CFR 234.203 - Control circuits.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 4 2014-10-01 2014-10-01 false Control circuits. 234.203 Section 234.203... EMERGENCY NOTIFICATION SYSTEMS Maintenance, Inspection, and Testing Maintenance Standards § 234.203 Control circuits. All control circuits that affect the safe operation of a highway-rail grade crossing warning...

Computer circuit card puller

NASA Technical Reports Server (NTRS)

Sawyer, R. V.; Szuwalski, B. (Inventor)

1981-01-01

The invention generally relates to hand tools, and more particularly to an improved device for facilitating removal of printed circuit cards from a card rack characterized by longitudinal side rails arranged in a mutually spaced parallelism and a plurality of printed circuit cards extended between the rails of the rack.

One-shot pulse shaper circuit

NASA Technical Reports Server (NTRS)

Radys, R. G.

1968-01-01

Pulse shaper circuit exhibits low power dissipation, self setting, and easy triggering. It is basically a magnetic one-shot multivibrator consisting of two blocking oscillators and an inhibit circuit.

Fractionation of social brain circuits in autism spectrum disorders

PubMed Central

Simmons, W. Kyle; Milbury, Lydia A.; Wallace, Gregory L.; Cox, Robert W.; Martin, Alex

2012-01-01

Autism spectrum disorders are developmental disorders characterized by impairments in social and communication abilities and repetitive behaviours. Converging neuroscientific evidence has suggested that the neuropathology of autism spectrum disorders is widely distributed, involving impaired connectivity throughout the brain. Here, we evaluate the hypothesis that decreased connectivity in high-functioning adolescents with an autism spectrum disorder relative to typically developing adolescents is concentrated within domain-specific circuits that are specialized for social processing. Using a novel whole-brain connectivity approach in functional magnetic resonance imaging, we found that not only are decreases in connectivity most pronounced between regions of the social brain but also they are selective to connections between limbic-related brain regions involved in affective aspects of social processing from other parts of the social brain that support language and sensorimotor processes. This selective pattern was independently obtained for correlations with measures of social symptom severity, implying a fractionation of the social brain in autism spectrum disorders at the level of whole circuits. PMID:22791801

Fractionation of social brain circuits in autism spectrum disorders.

PubMed

Gotts, Stephen J; Simmons, W Kyle; Milbury, Lydia A; Wallace, Gregory L; Cox, Robert W; Martin, Alex

2012-09-01

Autism spectrum disorders are developmental disorders characterized by impairments in social and communication abilities and repetitive behaviours. Converging neuroscientific evidence has suggested that the neuropathology of autism spectrum disorders is widely distributed, involving impaired connectivity throughout the brain. Here, we evaluate the hypothesis that decreased connectivity in high-functioning adolescents with an autism spectrum disorder relative to typically developing adolescents is concentrated within domain-specific circuits that are specialized for social processing. Using a novel whole-brain connectivity approach in functional magnetic resonance imaging, we found that not only are decreases in connectivity most pronounced between regions of the social brain but also they are selective to connections between limbic-related brain regions involved in affective aspects of social processing from other parts of the social brain that support language and sensorimotor processes. This selective pattern was independently obtained for correlations with measures of social symptom severity, implying a fractionation of the social brain in autism spectrum disorders at the level of whole circuits.

Open circuit versus closed circuit enrichment of anodic biofilms in MFC: effect on performance and anodic communities.

PubMed

Larrosa-Guerrero, Amor; Scott, Keith; Katuri, Krishna P; Godinez, Carlos; Head, Ian M; Curtis, Thomas

2010-08-01

The influence of various carbon anodes; graphite, sponge, paper, cloth, felt, fiber, foam and reticulated vitreous carbon (RVC); on microbial fuel cell (MFC) performance is reported. The feed was brewery wastewater diluted in domestic wastewater. Biofilms were grown at open circuit or under an external load. Microbial diversity was analysed as a function of current and anode material. The bacterial community formed at open circuit was influenced by the anode material. However at closed circuit its role in determining the bacterial consortia formed was less important than the passage of current. The rate and extent of organic matter removal were similar for all materials: over 95% under closed circuit. The biofilm in MFCs working at open circuit and in the control reactors, increased COD removal by up to a factor of nine compared with that for baseline reactors. The average voltage output was 0.6 V at closed circuit, with an external resistor of 300 kOmega and 0.75 V at open circuit for all materials except RVC. The poor performance of this material might be related to the surface area available and concentration polarizations caused by the morphology of the material and the structure of the biofilm. Peak power varied from 1.3 mW m(-2) for RVC to 568 mW m(-2) for graphite with biofilm grown at closed circuit.

Leaky Integrate-and-Fire Neuron Circuit Based on Floating-Gate Integrator

PubMed Central

Kornijcuk, Vladimir; Lim, Hyungkwang; Seok, Jun Yeong; Kim, Guhyun; Kim, Seong Keun; Kim, Inho; Choi, Byung Joon; Jeong, Doo Seok

2016-01-01

The artificial spiking neural network (SNN) is promising and has been brought to the notice of the theoretical neuroscience and neuromorphic engineering research communities. In this light, we propose a new type of artificial spiking neuron based on leaky integrate-and-fire (LIF) behavior. A distinctive feature of the proposed FG-LIF neuron is the use of a floating-gate (FG) integrator rather than a capacitor-based one. The relaxation time of the charge on the FG relies mainly on the tunnel barrier profile, e.g., barrier height and thickness (rather than the area). This opens up the possibility of large-scale integration of neurons. The circuit simulation results offered biologically plausible spiking activity (<100 Hz) with a capacitor of merely 6 fF, which is hosted in an FG metal-oxide-semiconductor field-effect transistor. The FG-LIF neuron also has the advantage of low operation power (<30 pW/spike). Finally, the proposed circuit was subject to possible types of noise, e.g., thermal noise and burst noise. The simulation results indicated remarkable distributional features of interspike intervals that are fitted to Gamma distribution functions, similar to biological neurons in the neocortex. PMID:27242416

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

PubMed

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.

30 CFR 56.6403 - Branch circuits.

Code of Federal Regulations, 2010 CFR

2010-07-01

... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Electric Blasting § 56.6403 Branch circuits. (a) If electric blasting includes the use of branch circuits, each... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Branch circuits. 56.6403 Section 56.6403...

Focal plane infrared readout circuit

NASA Technical Reports Server (NTRS)

Pain, Bedabrata (Inventor)

2002-01-01

An infrared imager, such as a spectrometer, includes multiple infrared photodetectors and readout circuits for reading out signals from the photodetectors. Each readout circuit includes a buffered direct injection input circuit including a differential amplifier with active feedback provided through an injection transistor. The differential amplifier includes a pair of input transistors, a pair of cascode transistors and a current mirror load. Photocurrent from a photodetector can be injected onto an integration capacitor in the readout circuit with high injection efficiency at high speed. A high speed, low noise, wide dynamic range linear infrared multiplexer array for reading out infrared detectors with large capacitances can be achieved even when short exposure times are used. The effect of image lag can be reduced.

Pattern separation in the hippocampus: distinct circuits under different conditions.

PubMed

Kassab, Randa; Alexandre, Frédéric

2018-04-11

Pattern separation is a fundamental hippocampal process thought to be critical for distinguishing similar episodic memories, and has long been recognized as a natural function of the dentate gyrus (DG), supporting autoassociative learning in CA3. Understanding how neural circuits within the DG-CA3 network mediate this process has received much interest, yet the exact mechanisms behind remain elusive. Here, we argue for the case that sparse coding is necessary but not sufficient to ensure efficient separation and, alternatively, propose a possible interaction of distinct circuits which, nevertheless, act in synergy to produce a unitary function of pattern separation. The proposed circuits involve different functional granule-cell populations, a primary population mediates sparsification and provides recurrent excitation to the other populations which are related to additional pattern separation mechanisms with higher degrees of robustness against interference in CA3. A variety of top-down and bottom-up factors, such as motivation, emotion, and pattern similarity, control the selection of circuitry depending on circumstances. According to this framework, a computational model is implemented and tested against model variants in a series of numerical simulations and biological experiments. The results demonstrate that the model combines fast learning, robust pattern separation and high storage capacity. It also accounts for the controversy around the involvement of the DG during memory recall, explains other puzzling findings, and makes predictions that can inform future investigations.

Viral-genetic tracing of the input-output organization of a central noradrenaline circuit.

PubMed

Schwarz, Lindsay A; Miyamichi, Kazunari; Gao, Xiaojing J; Beier, Kevin T; Weissbourd, Brandon; DeLoach, Katherine E; Ren, Jing; Ibanes, Sandy; Malenka, Robert C; Kremer, Eric J; Luo, Liqun

2015-08-06

Deciphering how neural circuits are anatomically organized with regard to input and output is instrumental in understanding how the brain processes information. For example, locus coeruleus noradrenaline (also known as norepinephrine) (LC-NE) neurons receive input from and send output to broad regions of the brain and spinal cord, and regulate diverse functions including arousal, attention, mood and sensory gating. However, it is unclear how LC-NE neurons divide up their brain-wide projection patterns and whether different LC-NE neurons receive differential input. Here we developed a set of viral-genetic tools to quantitatively analyse the input-output relationship of neural circuits, and applied these tools to dissect the LC-NE circuit in mice. Rabies-virus-based input mapping indicated that LC-NE neurons receive convergent synaptic input from many regions previously identified as sending axons to the locus coeruleus, as well as from newly identified presynaptic partners, including cerebellar Purkinje cells. The 'tracing the relationship between input and output' method (or TRIO method) enables trans-synaptic input tracing from specific subsets of neurons based on their projection and cell type. We found that LC-NE neurons projecting to diverse output regions receive mostly similar input. Projection-based viral labelling revealed that LC-NE neurons projecting to one output region also project to all brain regions we examined. Thus, the LC-NE circuit overall integrates information from, and broadcasts to, many brain regions, consistent with its primary role in regulating brain states. At the same time, we uncovered several levels of specificity in certain LC-NE sub-circuits. These tools for mapping output architecture and input-output relationship are applicable to other neuronal circuits and organisms. More broadly, our viral-genetic approaches provide an efficient intersectional means to target neuronal populations based on cell type and projection pattern.

Circuit mechanisms encoding odors and driving aging-associated behavioral declines in Caenorhabditis elegans.

PubMed

Leinwand, Sarah G; Yang, Claire J; Bazopoulou, Daphne; Chronis, Nikos; Srinivasan, Jagan; Chalasani, Sreekanth H

2015-09-22

Chemosensory neurons extract information about chemical cues from the environment. How is the activity in these sensory neurons transformed into behavior? Using Caenorhabditis elegans, we map a novel sensory neuron circuit motif that encodes odor concentration. Primary neurons, AWC(ON) and AWA, directly detect the food odor benzaldehyde (BZ) and release insulin-like peptides and acetylcholine, respectively, which are required for odor-evoked responses in secondary neurons, ASEL and AWB. Consistently, both primary and secondary neurons are required for BZ attraction. Unexpectedly, this combinatorial code is altered in aged animals: odor-evoked activity in secondary, but not primary, olfactory neurons is reduced. Moreover, experimental manipulations increasing neurotransmission from primary neurons rescues aging-associated neuronal deficits. Finally, we correlate the odor responsiveness of aged animals with their lifespan. Together, these results show how odors are encoded by primary and secondary neurons and suggest reduced neurotransmission as a novel mechanism driving aging-associated sensory neural activity and behavioral declines.

Automatic Design of Digital Synthetic Gene Circuits

PubMed Central

Marchisio, Mario A.; Stelling, Jörg

2011-01-01

De novo computational design of synthetic gene circuits that achieve well-defined target functions is a hard task. Existing, brute-force approaches run optimization algorithms on the structure and on the kinetic parameter values of the network. However, more direct rational methods for automatic circuit design are lacking. Focusing on digital synthetic gene circuits, we developed a methodology and a corresponding tool for in silico automatic design. For a given truth table that specifies a circuit's input–output relations, our algorithm generates and ranks several possible circuit schemes without the need for any optimization. Logic behavior is reproduced by the action of regulatory factors and chemicals on the promoters and on the ribosome binding sites of biological Boolean gates. Simulations of circuits with up to four inputs show a faithful and unequivocal truth table representation, even under parametric perturbations and stochastic noise. A comparison with already implemented circuits, in addition, reveals the potential for simpler designs with the same function. Therefore, we expect the method to help both in devising new circuits and in simplifying existing solutions. PMID:21399700

Constraint and Contingency in Multifunctional Gene Regulatory Circuits

PubMed Central

Payne, Joshua L.; Wagner, Andreas

2013-01-01

Gene regulatory circuits drive the development, physiology, and behavior of organisms from bacteria to humans. The phenotypes or functions of such circuits are embodied in the gene expression patterns they form. Regulatory circuits are typically multifunctional, forming distinct gene expression patterns in different embryonic stages, tissues, or physiological states. Any one circuit with a single function can be realized by many different regulatory genotypes. Multifunctionality presumably constrains this number, but we do not know to what extent. We here exhaustively characterize a genotype space harboring millions of model regulatory circuits and all their possible functions. As a circuit's number of functions increases, the number of genotypes with a given number of functions decreases exponentially but can remain very large for a modest number of functions. However, the sets of circuits that can form any one set of functions becomes increasingly fragmented. As a result, historical contingency becomes widespread in circuits with many functions. Whether a circuit can acquire an additional function in the course of its evolution becomes increasingly dependent on the function it already has. Circuits with many functions also become increasingly brittle and sensitive to mutation. These observations are generic properties of a broad class of circuits and independent of any one circuit genotype or phenotype. PMID:23762020

49 CFR 236.721 - Circuit, control.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 4 2013-10-01 2013-10-01 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. ...

49 CFR 236.721 - Circuit, control.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 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. ...

49 CFR 236.721 - Circuit, control.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 4 2014-10-01 2014-10-01 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. ...

49 CFR 236.721 - Circuit, control.

Code of Federal Regulations, 2010 CFR

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. ...

Plasticity in single neuron and circuit computations

NASA Astrophysics Data System (ADS)

Destexhe, Alain; Marder, Eve

2004-10-01

Plasticity in neural circuits can result from alterations in synaptic strength or connectivity, as well as from changes in the excitability of the neurons themselves. To better understand the role of plasticity in the brain, we need to establish how brain circuits work and the kinds of computations that different circuit structures achieve. By linking theoretical and experimental studies, we are beginning to reveal the consequences of plasticity mechanisms for network dynamics, in both simple invertebrate circuits and the complex circuits of mammalian cerebral cortex.

Tester Detects Steady-Short Or Intermittent-Open Circuits

NASA Technical Reports Server (NTRS)

Anderson, Bobby L.

1990-01-01

Momentary open circuits or steady short circuits trigger buzzer. Simple, portable, lightweight testing circuit sounds long-duration alarm when it detects steady short circuit or momentary open circuit in coaxial cable or other two-conductor transmission line. Tester sensitive to discontinuities lasting 10 microseconds or longer. Used extensively for detecting intermittent open shorts in accelerometer and extensometer cables. Also used as ordinary buzzer-type continuity checker to detect steady short or open circuits.

Packaging Of Control Circuits In A Robot Arm

NASA Technical Reports Server (NTRS)

Kast, William

1994-01-01

Packaging system houses and connects control circuitry mounted on circuit boards within shoulder, upper section, and lower section of seven-degree-of-freedom robot arm. Has modular design that incorporates surface-mount technology, multilayer circuit boards, large-scale integrated circuits, and multi-layer flat cables between sections for compactness. Three sections of robot arm contain circuit modules in form of stardardized circuit boards. Each module contains two printed-circuit cards, one of each face.

Microfabricated Circuits for Terahertz Wave Amplification and Terahertz Biosensors

NASA Astrophysics Data System (ADS)

Fawole, Olutosin Charles

The terahertz frequency band extends from deep infrared (100 THz) down to millimeter waves (0.4 THz), and this band was mostly inaccessible due to the lack of appropriate sources and detectors. Those with access to this band had to endure the small-intensity pulsed signals (nanowatts to microwatts) that the terahertz sources of those times could provide. In recent years, however, sufficient development has led to the availability of terahertz sources with sufficient power (1-100 muW) and the ease of use these sources has in turn enabled researchers to develop newer sources, detectors, and application areas. The terahertz regime is interesting because a) many molecules have vibrational, rotation and transition absorption bands in this regime, b) the terahertz electromagnetic wavelength is sufficiently small to resolve centimeter to millimeter scale objects, and c) scattering and absorption in metals in the terahertz regime make it very challenging to devise terahertz signal processing circuits. Thus, performing terahertz reflection/transmission measurements may enable precise identification of chemicals in a sample. Furthermore, small wavelengths and strong scattering by metallic objects make imaging with terahertz waves quite attractive. Finally, the ability to devise terahertz communication circuits and links will provide access to a frequency domain that is restricted and not available to others. One of the main objectives of this work is to develop 0.75 - 1.1 terahertz (free space wavelength 272 mum - 400 ?mum) amplifiers. Another objective of this work is to explore the suitability of terahertz waves in biological imaging and sensing. The terahertz amplifiers developed in this work consisted of distributed components such as rectangular waveguides and cylindrical dielectric resonators. In contrast to discrete amplifiers, which are based on solid-state devices, distributed traveling wave amplifiers can potentially handle and produce larger powers. Three

Finding False Paths in Sequential Circuits

NASA Astrophysics Data System (ADS)

Matrosova, A. Yu.; Andreeva, V. V.; Chernyshov, S. V.; Rozhkova, S. V.; Kudin, D. V.

2018-02-01

Method of finding false paths in sequential circuits is developed. In contrast with heuristic approaches currently used abroad, the precise method based on applying operations on Reduced Ordered Binary Decision Diagrams (ROBDDs) extracted from the combinational part of a sequential controlling logic circuit is suggested. The method allows finding false paths when transfer sequence length is not more than the given value and obviates the necessity of investigation of combinational circuit equivalents of the given lengths. The possibilities of using of the developed method for more complicated circuits are discussed.

Detecting short circuits during assembly

NASA Technical Reports Server (NTRS)

Deboo, G. J.

1980-01-01

Detector circuit identifies shorts between bus bars of electronic equipment being wired. Detector sounds alarm and indicates which planes are shorted. Power and ground bus bars are scanned continuously until short circuit occurs.

Moving the boundary between wavelength resources in optical packet and circuit integrated ring network.

PubMed

Furukawa, Hideaki; Miyazawa, Takaya; Wada, Naoya; Harai, Hiroaki

2014-01-13

Optical packet and circuit integrated (OPCI) networks provide both optical packet switching (OPS) and optical circuit switching (OCS) links on the same physical infrastructure using a wavelength multiplexing technique in order to deal with best-effort services and quality-guaranteed services. To immediately respond to changes in user demand for OPS and OCS links, OPCI networks should dynamically adjust the amount of wavelength resources for each link. We propose a resource-adjustable hybrid optical packet/circuit switch and transponder. We also verify that distributed control of resource adjustments can be applied to the OPCI ring network testbed we developed. In cooperation with the resource adjustment mechanism and the hybrid switch and transponder, we demonstrate that automatically allocating a shared resource and moving the wavelength resource boundary between OPS and OCS links can be successfully executed, depending on the number of optical paths in use.

Mapping from multiple-control Toffoli circuits to linear nearest neighbor quantum circuits

NASA Astrophysics Data System (ADS)

Cheng, Xueyun; Guan, Zhijin; Ding, Weiping

2018-07-01

In recent years, quantum computing research has been attracting more and more attention, but few studies on the limited interaction distance between quantum bits (qubit) are deeply carried out. This paper presents a mapping method for transforming multiple-control Toffoli (MCT) circuits into linear nearest neighbor (LNN) quantum circuits instead of traditional decomposition-based methods. In order to reduce the number of inserted SWAP gates, a novel type of gate with the optimal LNN quantum realization was constructed, namely NNTS gate. The MCT gate with multiple control bits could be better cascaded by the NNTS gates, in which the arrangement of the input lines was LNN arrangement of the MCT gate. Then, the communication overhead measurement model on inserted SWAP gate count from the original arrangement to the new arrangement was put forward, and we selected one of the LNN arrangements with the minimum SWAP gate count. Moreover, the LNN arrangement-based mapping algorithm was given, and it dealt with the MCT gates in turn and mapped each MCT gate into its LNN form by inserting the minimum number of SWAP gates. Finally, some simplification rules were used, which can further reduce the final quantum cost of the LNN quantum circuit. Experiments on some benchmark MCT circuits indicate that the direct mapping algorithm results in fewer additional SWAP gates in about 50%, while the average improvement rate in quantum cost is 16.95% compared to the decomposition-based method. In addition, it has been verified that the proposed method has greater superiority for reversible circuits cascaded by MCT gates with more control bits.

Investigation of noise insensitive electronic circuits for automotive applications with particular regard to MOS circuits

NASA Astrophysics Data System (ADS)

Gorille, I.

1980-11-01

The application of MOS switching circuits of high complexity in essential automobile systems, such as ignition and injection, was investigated. A bipolar circuit technology, current hogging logic (CHL), was compared to MOS technologies for its competitiveness. The functional requirements of digital automotive systems can only be met by technologies allowing large packing densities and medium speeds. The properties of n-MOS and CMOS are promising whereas the electrical power needed by p-MOS circuits is in general prohibitively large.

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

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electric equipment and circuits; overload and short circuit protection. 75.518 Section 75.518 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.518 Electric...

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

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electric equipment and circuits; overload and short circuit protection. 75.518 Section 75.518 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.518 Electric...

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

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electric equipment and circuits; overload and short circuit protection. 75.518 Section 75.518 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.518 Electric...

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

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electric equipment and circuits; overload and short circuit protection. 75.518 Section 75.518 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.518 Electric...

Distribution of TTX-sensitive voltage-gated sodium channels in primary sensory endings of mammalian muscle spindles.

PubMed

Carrasco, Dario I; Vincent, Jacob A; Cope, Timothy C

2017-04-01

Knowledge of the molecular mechanisms underlying signaling of mechanical stimuli by muscle spindles remains incomplete. In particular, the ionic conductances that sustain tonic firing during static muscle stretch are unknown. We hypothesized that tonic firing by spindle afferents depends on sodium persistent inward current (INaP) and tested for the necessary presence of the appropriate voltage-gated sodium (NaV) channels in primary sensory endings. The NaV 1.6 isoform was selected for both its capacity to produce INaP and for its presence in other mechanosensors that fire tonically. The present study shows that NaV 1.6 immunoreactivity (IR) is concentrated in heminodes, presumably where tonic firing is generated, and we were surprised to find NaV 1.6 IR strongly expressed also in the sensory terminals, where mechanotransduction occurs. This spatial pattern of NaV 1.6 IR distribution was consistent for three mammalian species (rat, cat, and mouse), as was tonic firing by primary spindle afferents. These findings meet some of the conditions needed to establish participation of INaP in tonic firing by primary sensory endings. The study was extended to two additional NaV isoforms, selected for their sensitivity to TTX, excluding TTX-resistant NaV channels, which alone are insufficient to support firing by primary spindle endings. Positive immunoreactivity was found for NaV 1.1 , predominantly in sensory terminals together with NaV 1.6 and for NaV 1.7 , mainly in preterminal axons. Differential distribution in primary sensory endings suggests specialized roles for these three NaV isoforms in the process of mechanosensory signaling by muscle spindles. NEW & NOTEWORTHY The molecular mechanisms underlying mechanosensory signaling responsible for proprioceptive functions are not completely elucidated. This study provides the first evidence that voltage-gated sodium channels (NaVs) are expressed in the spindle primary sensory ending, where NaVs are found at every site

Millimeter And Submillimeter-Wave Integrated Circuits On Quartz

NASA Technical Reports Server (NTRS)

Mehdi, Imran; Mazed, Mohammad; Siegel, Peter; Smith, R. Peter

1995-01-01

Proposed Quartz substrate Upside-down Integrated Device (QUID) relies on UV-curable adhesive to bond semiconductor with quartz. Integrated circuits including planar GaAs Schottky diodes and passive circuit elements (such as bandpass filters) fabricated on quartz substrates. Circuits designed to operate as mixers in waveguide circuit at millimeter and submillimeter wavelengths. Integrated circuits mechanically more robust, larger, and easier to handle than planar Schottky diode chips. Quartz substrate more suitable for waveguide circuits than GaAs substrate.

ELECTRONIC MULTIPLIER CIRCUIT

DOEpatents

Thomas, R.E.

1959-08-25

An electronic multiplier circuit is described in which an output voltage having an amplitude proportional to the product or quotient of the input signals is accomplished in a novel manner which facilitates simplicity of circuit construction and a high degree of accuracy in accomplishing the multiplying and dividing function. The circuit broadly comprises a multiplier tube in which the plate current is proportional to the voltage applied to a first control grid multiplied by the difference between voltage applied to a second control grid and the voltage applied to the first control grid. Means are provided to apply a first signal to be multiplied to the first control grid together with means for applying the sum of the first signal to be multiplied and a second signal to be multiplied to the second control grid whereby the plate current of the multiplier tube is proportional to the product of the first and second signals to be multiplied.

The intralaminar thalamus—an expressway linking visual stimuli to circuits determining agency and action selection

PubMed Central

Fisher, Simon D.; Reynolds, John N. J.

2014-01-01

Anatomical investigations have revealed connections between the intralaminar thalamic nuclei and areas such as the superior colliculus (SC) that receive short latency input from visual and auditory primary sensory areas. The intralaminar nuclei in turn project to the major input nucleus of the basal ganglia, the striatum, providing this nucleus with a source of subcortical excitatory input. Together with a converging input from the cerebral cortex, and a neuromodulatory dopaminergic input from the midbrain, the components previously found necessary for reinforcement learning in the basal ganglia are present. With this intralaminar sensory input, the basal ganglia are thought to play a primary role in determining what aspect of an organism’s own behavior has caused salient environmental changes. Additionally, subcortical loops through thalamic and basal ganglia nuclei are proposed to play a critical role in action selection. In this mini review we will consider the anatomical and physiological evidence underlying the existence of these circuits. We will propose how the circuits interact to modulate basal ganglia output and solve common behavioral learning problems of agency determination and action selection. PMID:24765070

Space Station power distribution and control

NASA Technical Reports Server (NTRS)

Willis, A. H.

1986-01-01

A general description of the Space Station is given with the basic requirements of the power distribution and controls system presented. The dual bus and branch circuit concepts are discussed and a computer control method presented.

Frequency and distribution of primary site among gender minority cancer patients: An analysis of U.S. national surveillance data.

PubMed

Nash, Rebecca; Ward, Kevin C; Jemal, Ahmedin; Sandberg, David E; Tangpricha, Vin; Goodman, Michael

2018-03-09

Transgender people and persons with disorders of sex development (DSD) are two separate categories of gender minorities, each characterized by unique cancer risk factors. Although cancer registry data typically include only two categories of sex, registrars have the option of indicating that a patient is transgender or has a DSD. Data for primary cancer cases in 46 states and the District of Columbia were obtained from the North American Association of Central Cancer Registries (NAACCR) database for the period 1995-2013. The distributions of primary sites and categories of cancers with shared risk factors were examined separately for transgender and DSD patients and compared to the corresponding distributions in male and female cancer patients. Proportional incidence ratios were calculated by dividing the number of observed cases by the number of expected cases. Expected cases were calculated based on the age- and year of diagnosis-specific proportions of cases in each cancer category observed among male and female patients. Transgender patients have significantly elevated proportional incidence ratios (95% confidence intervals) for viral infection induced cancers compared to either males (2.3; 2.0-2.7) or females (3.3; 2.8-3.7). Adult DSD cancer patients have a similar distribution of primary sites compared to male or female patients but DSD children with cancer have ten times more cases of testicular malignancies than expected (95% confidence interval: 4.7-20). The proportions of certain primary sites and categories of malignancies among transgender and DSD cancer patients are different from the proportions observed for male or female patients. Copyright © 2018 Elsevier Ltd. All rights reserved.

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

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electric equipment and circuits; overload and short-circuit protection. 77.506 Section 77.506 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES...

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

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electric equipment and circuits; overload and short-circuit protection. 77.506 Section 77.506 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES...

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

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electric equipment and circuits; overload and short-circuit protection. 77.506 Section 77.506 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES...

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

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electric equipment and circuits; overload and short-circuit protection. 77.506 Section 77.506 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES...

SEMICONDUCTOR INTEGRATED CIRCUITS: A reconfigurable analog baseband circuit for WLAN, WCDMA, and Bluetooth

NASA Astrophysics Data System (ADS)

Tao, Tong; Baoyong, Chi; Ziqiang, Wang; Ying, Zhang; Hanjun, Jiang; Zhihua, Wang

2010-05-01

A reconfigurable analog baseband circuit for WLAN, WCDMA, and Bluetooth in 0.35 μm CMOS is presented. The circuit consists of two variable gain amplifiers (VGA) in cascade and a Gm-C elliptic low-pass filter (LPF). The filter-order and the cut-off frequency of the LPF can be reconfigured to satisfy the requirements of various applications. In order to achieve the optimum power consumption, the bandwidth of the VGAs can also be dynamically reconfigured and some Gm cells can be cut off in the given application. Simulation results show that the analog baseband circuit consumes 16.8 mW for WLAN, 8.9 mW for WCDMA and only 6.5 mW for Bluetooth, all with a 3 V power supply. The analog baseband circuit could provide -10 to +40 dB variable gain, third-order low pass filtering with 1 MHz cut-off frequency for Bluetooth, fourth-order low pass filtering with 2.2 MHz cut-off frequency for WCDMA, and fifth-order low pass filtering with 11 MHz cut-off frequency for WLAN, respectively.

Study of Piezoelectric Vibration Energy Harvester with non-linear conditioning circuit using an integrated model

NASA Astrophysics Data System (ADS)

Manzoor, Ali; Rafique, Sajid; Usman Iftikhar, Muhammad; Mahmood Ul Hassan, Khalid; Nasir, Ali

2017-08-01

Piezoelectric vibration energy harvester (PVEH) consists of a cantilever bimorph with piezoelectric layers pasted on its top and bottom, which can harvest power from vibrations and feed to low power wireless sensor nodes through some power conditioning circuit. In this paper, a non-linear conditioning circuit, consisting of a full-bridge rectifier followed by a buck-boost converter, is employed to investigate the issues of electrical side of the energy harvesting system. An integrated mathematical model of complete electromechanical system has been developed. Previously, researchers have studied PVEH with sophisticated piezo-beam models but employed simplistic linear circuits, such as resistor, as electrical load. In contrast, other researchers have worked on more complex non-linear circuits but with over-simplified piezo-beam models. Such models neglect different aspects of the system which result from complex interactions of its electrical and mechanical subsystems. In this work, authors have integrated the distributed parameter-based model of piezo-beam presented in literature with a real world non-linear electrical load. Then, the developed integrated model is employed to analyse the stability of complete energy harvesting system. This work provides a more realistic and useful electromechanical model having realistic non-linear electrical load unlike the simplistic linear circuit elements employed by many researchers.

Faster Hall-Effect Current-Measuring Circuit

NASA Technical Reports Server (NTRS)

Sullender, Craig C.; Johnson, Daniel D.; Walker, Daniel D.

1993-01-01

Current-measuring circuit operates on Hall-effect-sensing and magnetic-field-nulling principles similar to those described in article, "Nulling Hall-Effect Current-Measuring Circuit" (LEW-15023), but simpler and responds faster. Designed without feedback loop, and analog pulse-width-modulated output indicates measured current. Circuit measures current at frequency higher than bandwidth of its Hall-effect sensor.

The dc power circuits: A compilation

NASA Technical Reports Server (NTRS)

1972-01-01

A compilation of reports concerning power circuits is presented for the dissemination of aerospace information to the general public as part of the NASA Technology Utilization Program. The descriptions for the electronic circuits are grouped as follows: dc power supplies, power converters, current-voltage power supply regulators, overload protection circuits, and dc constant current power supplies.

Electrical Circuit Tester

DOEpatents

Love, Frank

2006-04-18

An electrical circuit testing device is provided, comprising a case, a digital voltage level testing circuit with a display means, a switch to initiate measurement using the device, a non-shorting switching means for selecting pre-determined electrical wiring configurations to be tested in an outlet, a terminal block, a five-pole electrical plug mounted on the case surface and a set of adapters that can be used for various multiple-pronged electrical outlet configurations for voltages from 100 600 VAC from 50 100 Hz.

Switching-type regulator circuit has increased efficiency

NASA Technical Reports Server (NTRS)

Clapp, W. M.

1967-01-01

Switching series regulator circuit uses an inductive network to feed most of the current applied to the control circuit to the load. This circuit eliminates resistive losses and the need for heat sinks.

Hybrid stretchable circuits on silicone substrate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robinson, A., E-mail: adam.1.robinson@nokia.com; Aziz, A., E-mail: a.aziz1@lancaster.ac.uk; Liu, Q.

When rigid and stretchable components are integrated onto a single elastic carrier substrate, large strain heterogeneities appear in the vicinity of the deformable-non-deformable interfaces. In this paper, we report on a generic approach to manufacture hybrid stretchable circuits where commercial electronic components can be mounted on a stretchable circuit board. Similar to printed circuit board development, the components are electrically bonded on the elastic substrate and interconnected with stretchable electrical traces. The substrate—a silicone matrix carrying concentric rigid disks—ensures both the circuit elasticity and the mechanical integrity of the most fragile materials.

46 CFR 28.365 - Overcurrent protection and switched circuits.

Code of Federal Regulations, 2010 CFR

2010-10-01

... a steering circuit, each circuit must be protected against both overload and short circuit. Each overcurrent device in a steering system power and control circuit must provide short circuit protection only... 46 Shipping 1 2010-10-01 2010-10-01 false Overcurrent protection and switched circuits. 28.365...

Brain Embodiment of Syntax and Grammar: Discrete Combinatorial Mechanisms Spelt Out in Neuronal Circuits

ERIC Educational Resources Information Center

Pulvermuller, Friedemann

2010-01-01

Neuroscience has greatly improved our understanding of the brain basis of abstract lexical and semantic processes. The neuronal devices underlying words and concepts are distributed neuronal assemblies reaching into sensory and motor systems of the cortex and, at the cognitive level, information binding in such widely dispersed circuits is…

On equivalent resistance of electrical circuits

NASA Astrophysics Data System (ADS)

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.

Logic circuits from zero forcing.

PubMed

Burgarth, Daniel; Giovannetti, Vittorio; Hogben, Leslie; Severini, Simone; Young, Michael

We design logic circuits based on the notion of zero forcing on graphs; each gate of the circuits is a gadget in which zero forcing is performed. We show that such circuits can evaluate every monotone Boolean function. By using two vertices to encode each logical bit, we obtain universal computation. We also highlight a phenomenon of "back forcing" as a property of each function. Such a phenomenon occurs in a circuit when the input of gates which have been already used at a given time step is further modified by a computation actually performed at a later stage. Finally, we show that zero forcing can be also used to implement reversible computation. The model introduced here provides a potentially new tool in the analysis of Boolean functions, with particular attention to monotonicity. Moreover, in the light of applications of zero forcing in quantum mechanics, the link with Boolean functions may suggest a new directions in quantum control theory and in the study of engineered quantum spin systems. It is an open technical problem to verify whether there is a link between zero forcing and computation with contact circuits.

Practical applications of digital integrated circuits. Part 2: Minimization techniques, code conversion, flip-flops, and asynchronous circuits

NASA Technical Reports Server (NTRS)

1972-01-01

Here, the 7400 line of transistor to transistor logic (TTL) devices is emphasized almost exclusively where hardware is concerned. However, it should be pointed out that the logic theory contained herein applies to all hardware. Binary numbers, simplification of logic circuits, code conversion circuits, basic flip-flop theory, details about series 54/7400, and asynchronous circuits are discussed.

Counterpulse railgun energy recovery circuit

DOEpatents

Honig, E.M.

1984-09-28

The invention presented relates to a high-power pulsing circuit and more particularly to a repetitive pulse inductive energy storage and transfer circuit for an electromagnetic launcher. In an electromagnetic launcher such as a railgun for propelling a projectile at high velocity, a counterpulse energy recovery circuit is employed to transfer stored inductive energy from a source inductor to the railgun inductance to propel the projectile down the railgun. Switching circuitry and an energy transfer capacitor are used to switch the energy back to the source inductor in readiness for a repetitive projectile propelling cycle.

Overpulse railgun energy recovery circuit

DOEpatents

Honig, E.M.

1984-09-28

The invention presented relates to a high-power pulsing circuit and more particularly to a repetitive pulse inductive energy storage and transfer circuit for an electromagnetic launcher. In an electromagnetic launcher such as a railgun for propelling a projectile at high velocity, an overpulse energy recovery circuit is employed to transfer stored inductive energy from a source inductor to the railgun inductance to propel the projectile down the railgun. Switching circuitry and an energy transfer capacitor are used to switch the energy back to the source inductor in readiness for a repetitive projectile propelling cycle.

49 CFR 236.723 - Circuit, double wire; line.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, double wire; line. 236.723 Section 236... § 236.723 Circuit, double wire; line. An electric circuit not employing a common return wire; a circuit formed by individual wires throughout. ...

49 CFR 236.723 - Circuit, double wire; line.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Circuit, double wire; line. 236.723 Section 236... § 236.723 Circuit, double wire; line. An electric circuit not employing a common return wire; a circuit formed by individual wires throughout. ...

Circuit Training: Exercise That Counts.

ERIC Educational Resources Information Center

Mosher, Patricia E.; Underwood, Steven A.

1992-01-01

Describes how to assess and implement aerobic circuit training, which involves multistation weight training apparatus, handweights, and aerobic activity equipment to increase cardiovascular fitness and strength. Designed for high school and college students, the circuit requires 25 minutes to complete. (SM)

Overload-protector/fault-indicator circuit

NASA Technical Reports Server (NTRS)

Paluka, J. R.; Moore, S. F.

1977-01-01

Circuit incorporates three-terminal current limiter (78M24) to increase overall reliability and to eliminate transistor burnouts resulting from shorted interconnection lines and other overloads. Fact-acting light emitting diodes across the limiters show status of transistor output circuits.

Energy, angular and spatial distributions of primary electrons inside photoconducting materials for digital mammography: Monte Carlo simulation studies.

PubMed

Sakellaris, T; Spyrou, G; Tzanakos, G; Panayiotakis, G

2007-11-07

Materials such as a-Se, a-As(2)Se(3), GaSe, GaAs, Ge, CdTe, CdZnTe, Cd(0.8)Zn(0.2)Te, ZnTe, PbO, TlBr, PbI(2) and HgI(2) are potential candidates as photoconductors in direct detectors for digital mammography. The x-ray induced primary electrons inside a photoconductor's bulk comprise the initial signal that propagates and forms the final signal (image) on the detector's electrodes. An already developed model for a-Se has been properly extended to simulate the primary electron production in the materials mentioned. Primary electron characteristics, such as their energy, angular and spatial distributions that strongly influence the characteristics of the final image, were studied for both monoenergetic and polyenergetic x-ray spectra in the mammographic energy range. The characteristic feature in the electron energy distributions for PbI(2) and HgI(2) is the atomic deexcitation peaks, whereas for the rest of the materials their shape can also be influenced by the electrons produced from primary photons. The electrons have a small tendency to be forward ejected whereas they prefer to be ejected perpendicular (theta = pi/2) to the incident beam's axis and at two lobes around phi = 0 and phi = pi. At practical mammographic energies (15-40 keV) a-Se, a-As(2)Se(3) and Ge have the minimum azimuthal uniformity whereas CdZnTe, Cd(0.8)Zn(0.2)Te and CdTe the maximum one. The spatial distributions for a-Se, a-As(2)Se(3), GaSe, GaAs, Ge, PbO and TlBr are almost independent of the polyenergetic spectrum, while those for CdTe, CdZnTe, Cd(0.8)Zn(0.2)Te, ZnTe, PbI(2) and HgI(2) have a spectrum dependence. In the practical mammographic energy range and at this primitive stage of primary electron production, a-Se has the best inherent spatial resolution as compared to the rest of the photoconductors. PbO has the minimum bulk space in which electrons can be produced whereas CdTe has the maximum one.

Active shunt capacitance cancelling oscillator circuit

DOEpatents

Wessendorf, Kurt O.

2003-09-23

An oscillator circuit is disclosed which can be used to produce oscillation using a piezoelectric crystal, with a frequency of oscillation being largely independent of any shunt capacitance associated with the crystal (i.e. due to electrodes on the surfaces of the crystal and due to packaging and wiring for the crystal). The oscillator circuit is based on a tuned gain stage which operates the crystal at a frequency, f, near a series resonance frequency, f.sub.S. The oscillator circuit further includes a compensation circuit that supplies all the ac current flow through the shunt resistance associated with the crystal so that this ac current need not be supplied by the tuned gain stage. The compensation circuit uses a current mirror to provide the ac current flow based on the current flow through a reference capacitor that is equivalent to the shunt capacitance associated with the crystal. The oscillator circuit has applications for driving piezoelectric crystals for sensing of viscous, fluid or solid media by detecting a change in the frequency of oscillation of the crystal and a resonator loss which occur from contact of an exposed surface of the crystal by the viscous, fluid or solid media.

Nonlinear relaxation algorithms for circuit simulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saleh, R.A.

Circuit simulation is an important Computer-Aided Design (CAD) tool in the design of Integrated Circuits (IC). However, the standard techniques used in programs such as SPICE result in very long computer-run times when applied to large problems. In order to reduce the overall run time, a number of new approaches to circuit simulation were developed and are described. These methods are based on nonlinear relaxation techniques and exploit the relative inactivity of large circuits. Simple waveform-processing techniques are described to determine the maximum possible speed improvement that can be obtained by exploiting this property of large circuits. Three simulation algorithmsmore » are described, two of which are based on the Iterated Timing Analysis (ITA) method and a third based on the Waveform-Relaxation Newton (WRN) method. New programs that incorporate these techniques were developed and used to simulate a variety of industrial circuits. The results from these simulations are provided. The techniques are shown to be much faster than the standard approach. In addition, a number of parallel aspects of these algorithms are described, and a general space-time model of parallel-task scheduling is developed.« less

Fractal Electronic Circuits Assembled From Nanoclusters

NASA Astrophysics Data System (ADS)

Fairbanks, M. S.; McCarthy, D.; Taylor, R. P.; Brown, S. A.

2009-07-01

Many patterns in nature can be described using fractal geometry. The effect of this fractal character is an array of properties that can include high internal connectivity, high dispersivity, and enhanced surface area to volume ratios. These properties are often desirable in applications and, consequently, fractal geometry is increasingly employed in technologies ranging from antenna to storm barriers. In this paper, we explore the application of fractal geometry to electrical circuits, inspired by the pervasive fractal structure of neurons in the brain. We show that, under appropriate growth conditions, nanoclusters of Sb form into islands on atomically flat substrates via a process close to diffusion-limited aggregation (DLA), establishing fractal islands that will form the basis of our fractal circuits. We perform fractal analysis of the islands to determine the spatial scaling properties (characterized by the fractal dimension, D) of the proposed circuits and demonstrate how varying growth conditions can affect D. We discuss fabrication approaches for establishing electrical contact to the fractal islands. Finally, we present fractal circuit simulations, which show that the fractal character of the circuit translates into novel, non-linear conduction properties determined by the circuit's D value.

A programming language for composable DNA circuits.

PubMed

Phillips, Andrew; Cardelli, Luca

2009-08-06

Recently, a range of information-processing circuits have been implemented in DNA by using strand displacement as their main computational mechanism. Examples include digital logic circuits and catalytic signal amplification circuits that function as efficient molecular detectors. As new paradigms for DNA computation emerge, the development of corresponding languages and tools for these paradigms will help to facilitate the design of DNA circuits and their automatic compilation to nucleotide sequences. We present a programming language for designing and simulating DNA circuits in which strand displacement is the main computational mechanism. The language includes basic elements of sequence domains, toeholds and branch migration, and assumes that strands do not possess any secondary structure. The language is used to model and simulate a variety of circuits, including an entropy-driven catalytic gate, a simple gate motif for synthesizing large-scale circuits and a scheme for implementing an arbitrary system of chemical reactions. The language is a first step towards the design of modelling and simulation tools for DNA strand displacement, which complements the emergence of novel implementation strategies for DNA computing.

A programming language for composable DNA circuits

PubMed Central

Phillips, Andrew; Cardelli, Luca

2009-01-01

Recently, a range of information-processing circuits have been implemented in DNA by using strand displacement as their main computational mechanism. Examples include digital logic circuits and catalytic signal amplification circuits that function as efficient molecular detectors. As new paradigms for DNA computation emerge, the development of corresponding languages and tools for these paradigms will help to facilitate the design of DNA circuits and their automatic compilation to nucleotide sequences. We present a programming language for designing and simulating DNA circuits in which strand displacement is the main computational mechanism. The language includes basic elements of sequence domains, toeholds and branch migration, and assumes that strands do not possess any secondary structure. The language is used to model and simulate a variety of circuits, including an entropy-driven catalytic gate, a simple gate motif for synthesizing large-scale circuits and a scheme for implementing an arbitrary system of chemical reactions. The language is a first step towards the design of modelling and simulation tools for DNA strand displacement, which complements the emergence of novel implementation strategies for DNA computing. PMID:19535415

The Global Distribution of Precipitation and Clouds. Chapter 2.4

NASA Technical Reports Server (NTRS)

Shepherd, J. Marshall; Adler, Robert; Huffman, George; Rossow, William; Ritter, Michael; Curtis, Scott

2004-01-01

The water cycle is the key circuit moving water through the Earth's system. This large system, powered by energy from the sun, is a continuous exchange of moisture between the oceans, the atmosphere, and the land. Precipitation (including rain, snow, sleet, freezing rain, and hail), is the primary mechanism for transporting water from the atmosphere back to the Earth's surface and is the key physical process that links aspects of climate, weather, and the global water cycle. Global precipitation and associate cloud processes are critical for understanding the water cycle balance on a global scale and interactions with the Earth's climate system. However, unlike measurement of less dynamic and more homogenous meteorological fields such as pressure or even temperature, accurate assessment of global precipitation is particularly challenging due to its highly stochastic and rapidly changing nature. It is not uncommon to observe a broad spectrum of precipitation rates and distributions over very localized time scales. Furthermore, precipitating systems generally exhibit nonhomogeneous spatial distributions of rain rates over local to global domains.

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

ERIC Educational Resources Information Center

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…

High Speed Solid State Circuit Breaker

NASA Technical Reports Server (NTRS)

Podlesak, Thomas F.

1993-01-01

The U.S. Army Research Laboratory, Fort Monmouth, NJ, has developed and is installing two 3.3 MW high speed solid state circuit breakers at the Army's Pulse Power Center. These circuit breakers will interrupt 4160V three phase power mains in no more than 300 microseconds, two orders of magnitude faster than conventional mechanical contact type circuit breakers. These circuit breakers utilize Gate Turnoff Thyristors (GTO's) and are currently utility type devices using air cooling in an air conditioned enclosure. Future refinements include liquid cooling, either water or two phase organic coolant, and more advanced semiconductors. Each of these refinements promises a more compact, more reliable unit.

Conceptual studies for a mercury target circuit

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sigg, B.

1996-06-01

For the now favored target design of the European Spallation Source project, i.e. the version using mercury as target material, a basic concept of the primary system has been worked out. It does not include a detailed design of the various components of the target circuit, but tries to outline a feasible solution for the system. Besides the removal of the thermal power of about 3MW produced in the target by the proton beam, the primary system has to satisfy a number of other requirements related to processing, safety, and operation. The basic proposal uses an electromagnetic pump and amore » mercury-water intermediate heat excanger, but other alternatives are also being discussed. Basic safety requirements, i.e. protection against radiation and toxic mercury vapours, are satisfied by a design using an air-tight primary system containment, double-walled tubes in the intermediate heat exchanger, a fail-safe system for decay heat removal, and a remote handling facility for the active part of the system. Much engineering work has still to be done, because many details of the design of the mercury and gas processing systems remain to be clarified, the thermal-hydraulic components need further optimisation, the system for control and instrumentation is only known in outline and a through safety analysis will be required.« less

Fabric circuits and method of manufacturing fabric circuits

NASA Technical Reports Server (NTRS)

Chu, Andrew W. (Inventor); Dobbins, Justin A. (Inventor); Scully, Robert C. (Inventor); Trevino, Robert C. (Inventor); Lin, Greg Y. (Inventor); Fink, Patrick W. (Inventor)

2011-01-01

A flexible, fabric-based circuit comprises a non-conductive flexible layer of fabric and a conductive flexible layer of fabric adjacent thereto. A non-conductive thread, an adhesive, and/or other means may be used for attaching the conductive layer to the non-conductive layer. In some embodiments, the layers are attached by a computer-driven embroidery machine at pre-determined portions or locations in accordance with a pre-determined attachment layout before automated cutting. In some other embodiments, an automated milling machine or a computer-driven laser using a pre-designed circuit trace as a template cuts the conductive layer so as to separate an undesired portion of the conductive layer from a desired portion of the conductive layer. Additional layers of conductive fabric may be attached in some embodiments to form a multi-layer construct.

Parameters assessment of the inductively-coupled circuit for wireless power transfer

NASA Astrophysics Data System (ADS)

Isaev, Yu N.; Vasileva, O. V.; Budko, A. A.; Lefebvre, S.

2017-02-01

In this paper, a wireless power transfer model through the example of inductively-coupled coils of irregular shape in software package COMSOL Multiphysics is studied. Circuit parameters, such as inductance, coil resistance and self-capacitance were defined through electromagnetic energy by the finite-element method. The study was carried out according to Helmholtz equation. Spatial distribution of current per unit depending on frequency and the coupling coefficient for analysis of resonant frequency and spatial distribution of the vector magnetic potential at different distances between coils were presented. The resulting algorithm allows simulating the wireless power transfer between the inductively coupled coils of irregular shape with the assessment of the optimal parameters.

Principles of Genetic Circuit Design

PubMed Central

Brophy, Jennifer A.N.; Voigt, Christopher A.

2014-01-01

Cells are able to navigate environments, communicate, and build complex patterns by initiating gene expression in response to specific signals. Engineers need to harness this capability to program cells to perform tasks or build chemicals and materials that match the complexity seen in nature. This review describes new tools that aid the construction of genetic circuits. We show how circuit dynamics can be influenced by the choice of regulators and changed with expression “tuning knobs.” We collate the failure modes encountered when assembling circuits, quantify their impact on performance, and review mitigation efforts. Finally, we discuss the constraints that arise from operating within a living cell. Collectively, better tools, well-characterized parts, and a comprehensive understanding of how to compose circuits are leading to a breakthrough in the ability to program living cells for advanced applications, from living therapeutics to the atomic manufacturing of functional materials. PMID:24781324

SDN architecture for optical packet and circuit integrated networks

NASA Astrophysics Data System (ADS)

Furukawa, Hideaki; Miyazawa, Takaya

2016-02-01

We have been developing an optical packet and circuit integrated (OPCI) network, which realizes dynamic optical path, high-density packet multiplexing, and flexible wavelength resource allocation. In the OPCI networks, a best-effort service and a QoS-guaranteed service are provided by employing optical packet switching (OPS) and optical circuit switching (OCS) respectively, and users can select these services. Different wavelength resources are assigned for OPS and OCS links, and the amount of their wavelength resources are dynamically changed in accordance with the service usage conditions. To apply OPCI networks into wide-area (core/metro) networks, we have developed an OPCI node with a distributed control mechanism. Moreover, our OPCI node works with a centralized control mechanism as well as a distributed one. It is therefore possible to realize SDN-based OPCI networks, where resource requests and a centralized configuration are carried out. In this paper, we show our SDN architecture for an OPS system that configures mapping tables between IP addresses and optical packet addresses and switching tables according to the requests from multiple users via a web interface. While OpenFlow-based centralized control protocol is coming into widespread use especially for single-administrative, small-area (LAN/data-center) networks. Here, we also show an interworking mechanism between OpenFlow-based networks (OFNs) and the OPCI network for constructing a wide-area network, and a control method of wavelength resource selection to automatically transfer diversified flows from OFNs to the OPCI network.

Fast-responding short circuit protection system with self-reset for use in circuit supplied by DC power

NASA Technical Reports Server (NTRS)

Burns, Bradley M. (Inventor); Blalock, Norman N. (Inventor)

2011-01-01

A short circuit protection system includes an inductor, a switch, a voltage sensing circuit, and a controller. The switch and inductor are electrically coupled to be in series with one another. A voltage sensing circuit is coupled across the switch and the inductor. A controller, coupled to the voltage sensing circuit and the switch, opens the switch when a voltage at the output terminal of the inductor transitions from above a threshold voltage to below the threshold voltage. The controller closes the switch when the voltage at the output terminal of the inductor transitions from below the threshold voltage to above the threshold voltage.

Dual-circuit segmented rail phased induction motor

DOEpatents

Marder, Barry M.; Cowan, Jr., Maynard

2002-01-01

An improved linear motor utilizes two circuits, rather that one circuit and an opposed plate, to gain efficiency. The powered circuit is a flat conductive coil. The opposed segmented rail circuit is either a plurality of similar conductive coils that are shorted, or a plurality of ladders formed of opposed conductive bars connected by a plurality of spaced conductors. In each embodiment, the conductors are preferably cables formed from a plurality of intertwined insulated wires to carry current evenly.

Dive In to Aquatic Circuits.

ERIC Educational Resources Information Center

Goldfarb, Joseph M.

1995-01-01

The article presents a method for swimming teachers and coaches to stave off workout boredom in their students by using a circuit in the pool. After explaining how to set up a training circuit, the article describes sample stations and notes important safety precautions. (SM)

30 CFR 75.800-1 - Circuit breakers; location.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Circuit breakers; location. 75.800-1 Section 75.800-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY... § 75.800-1 Circuit breakers; location. Circuit breakers protecting high-voltage circuits entering an...

A SUBSATELLITE AREA-OF-VIEW CIRCUIT.

DTIC Science & Technology