WorldWideScience

Sample records for circuits enhance scientific

  1. Circuits Enhance Scientific Instruments and Safety Devices

    Science.gov (United States)

    2009-01-01

    Since its founding in 1958, NASA has pioneered the use of different frequencies on the electromagnetic spectrum - including X-ray, microwave, and infrared wavelengths - to gather information about distant celestial bodies. During the 1962 Mariner 2 mission, NASA used microwave radiometers that operated in the range of 15-23 gigahertz (GHz) to assess the surface temperature of Venus and to determine the percentage of water vapor in its atmosphere. Today, there is another area on the spectrum proving uniquely useful to scientists: the terahertz (THz) range, spanning from about 100 GHz-10,000 GHz. (1 THz equals approximately 1,000 GHz.) Terahertz frequencies span the lesser-known gap on the electromagnetic spectrum between microwave radiation and infrared (and visible) light, falling within the spectral range where most simple molecules resonate. This molecular resonance makes terahertz particularly useful for chemical spectroscopy and the remote sensing of specific molecules. In the 1990s, NASA began using frequencies above 300 GHz (more than an order of magnitude higher than the instrumentation on Mariner 2) to perform spectral analysis of molecular clouds and planetary atmospheres. Instruments using these higher frequencies have included the Microwave Limb Sounder (MLS) on the Upper Atmosphere Research Satellite (UARS), deployed from 1991-2001, and the Microwave Instrument for the Rosetta Orbiter (MIRO), launched in 2004. With UARS-MLS, NASA used advanced terahertz receivers to measure the emission signatures from atmospheric molecules, providing researchers with valuable data about the changes in the Earth s protective ozone layer. MIRO, set to rendezvous with the comet 67P Churyumov-Gerasimenko in 2014, will use terahertz instrumentation to analyze the comet s dust and gases. Although NASA has been a driving force behind the development of terahertz technology, scientific equipment for terahertz research - including transmitters, receivers, and basic test and

  2. Spectral Purity Enhancement via Polyphase Multipath Circuits

    OpenAIRE

    Mensink, Eisse; Klumperink, Eric; Nauta, Bram

    2004-01-01

    The central question of this paper is: can we enhance the spectral purity of nonlinear circuits by using polyphase multipath circuits? The basic idea behind polyphase multipath circuits is to split the nonlinear circuits into two or more paths and exploit phase differences between these paths to cancel undesired distortion products. It turns out that it is very well possible to use polyphase multipath circuits to cancel distortion products produced by a nonlinear circuit. Unfortunately, there...

  3. Enhancement of Linear Circuit Program

    DEFF Research Database (Denmark)

    Gaunholt, Hans; Dabu, Mihaela; Beldiman, Octavian

    1996-01-01

    In this report a preliminary user friendly interface has been added to the LCP2 program making it possible to describe an electronic circuit by actually drawing the circuit on the screen. Component values and other options and parameters can easily be set by the aid of the interface. The interfac...

  4. Scientific Research Enjoys Enhanced Support in China

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ Scientific research in China is receiving enhanced support from both the government and the public, as science and technology are playing an increasingly constructive role in the country's social progress and economic growth, states CAS President Lu Yongxiang.

  5. Circuit Model of Plasmon-Enhanced Fluorescence

    Directory of Open Access Journals (Sweden)

    Constantin Simovski

    2015-05-01

    Full Text Available Hybridized decaying oscillations in a nanosystem of two coupled elements—a quantum emitter and a plasmonic nanoantenna—are considered as a classical effect. The circuit model of the nanosystem extends beyond the assumption of inductive or elastic coupling and implies the near-field dipole-dipole interaction. Its results fit those of the previously developed classical model of Rabi splitting, however going much farther. Using this model, we show that the hybridized oscillations depending on the relationships between design parameters of the nanosystem correspond to several characteristic regimes of spontaneous emission. These regimes were previously revealed in the literature and explained involving semiclassical theory. Our original classical model is much simpler: it results in a closed-form solution for the emission spectra. It allows fast prediction of the regime for different distances and locations of the emitter with respect to the nanoantenna (of a given geometry if the dipole moment of the emitter optical transition and its field coupling constant are known.

  6. Enhanced low dose rate sensitivity (ELDRS) in bipolar linear circuits

    International Nuclear Information System (INIS)

    Enhanced Low Dose Rate Sensitivity (ELDRS) in bipolar linear transistors was first identified in bipolar microcircuit transistors in 1991 and demonstrated in bipolar linear circuits in 1994. Since then it has been a major topic of research, characterization and analysis. Data compendia of low dose rate enhancement factors were presented in 1996, 2001 and 2008, identifying 30 unique widely used circuit types as susceptible to ELDRS. A space experiment has verified the phenomenon for ELDRS parts in space. Early work on ELDRS was directed toward identifying mechanisms, characterizing circuits and developing hardness assurance methods, concentrating on accelerated testing techniques. More recently the research has focused on the effects of pre-irradiation elevated temperature stress (PETS), final passivation layers and molecular hydrogen in the package on the ELDRS response, providing a basis for developing ELDRS-free parts. In this review paper the phenomena of ELDRS, its characteristics, the most recent modeling results and the latest hardness assurance techniques are discussed. (author)

  7. Policy assessments to enhance EU scientific advice

    Science.gov (United States)

    Kowarsch, Martin

    2016-01-01

    The European Commission needs to amend its new Scientific Advice Mechanism. Highly integrated, participatory assessments of policy alternatives are required for multidimensional, value-laden policy issues such as the European Union's climate and energy policies.

  8. A multilevel multimodal circuit enhances action selection in Drosophila.

    Science.gov (United States)

    Ohyama, Tomoko; Schneider-Mizell, Casey M; Fetter, Richard D; Aleman, Javier Valdes; Franconville, Romain; Rivera-Alba, Marta; Mensh, Brett D; Branson, Kristin M; Simpson, Julie H; Truman, James W; Cardona, Albert; Zlatic, Marta

    2015-04-30

    Natural events present multiple types of sensory cues, each detected by a specialized sensory modality. Combining information from several modalities is essential for the selection of appropriate actions. Key to understanding multimodal computations is determining the structural patterns of multimodal convergence and how these patterns contribute to behaviour. Modalities could converge early, late or at multiple levels in the sensory processing hierarchy. Here we show that combining mechanosensory and nociceptive cues synergistically enhances the selection of the fastest mode of escape locomotion in Drosophila larvae. In an electron microscopy volume that spans the entire insect nervous system, we reconstructed the multisensory circuit supporting the synergy, spanning multiple levels of the sensory processing hierarchy. The wiring diagram revealed a complex multilevel multimodal convergence architecture. Using behavioural and physiological studies, we identified functionally connected circuit nodes that trigger the fastest locomotor mode, and others that facilitate it, and we provide evidence that multiple levels of multimodal integration contribute to escape mode selection. We propose that the multilevel multimodal convergence architecture may be a general feature of multisensory circuits enabling complex input-output functions and selective tuning to ecologically relevant combinations of cues. PMID:25896325

  9. Supermode control in integrated hybrid Si/III–V optoelectronic circuits for modal gain enhancement

    OpenAIRE

    Sun, Xiankai; Yariv, Amnon

    2009-01-01

    We propose using supermode control to enhance the modal gain in integrated hybrid Si/III–V optoelectronic circuits. Numerical simulations predict that a 4-fold enhancement in modal gain can be achieved with optimal design.

  10. Simultaneous enhancement of open-circuit voltage, short-circuit current density, and fill factor in polymer solar cells

    Energy Technology Data Exchange (ETDEWEB)

    He, Zhicai; Zhong, Chengmei; Wu, Hongbin; Su, Shijian; Cao, Yong [Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640 (China); Huang, Xun; Chen, Liwei [Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, 398 Ruoshui Road, Suzhou Industrial Park, Suzhou 215123 (China); Wong, Wai-Yeung [Institute of Molecular Functional Materials (Areas of Excellence Scheme, University Grants Committee, Hong Kong) and Department of Chemistry and Centre for Advanced Luminescence Materials, Hong Kong Baptist University, Waterloo Road, Hong Kong (China)

    2011-10-25

    Simultaneous enhancement of open-circuit voltage, short-circuit current density, and fill factor in highly efficient polymer solar cells by incorporating an alcohol/water-soluble conjugated polymer as cathode interlayer is domonstrated. When combined with a low-bandgap polymer PTB7 as the electron donor material, the power efficiency of the devices is improved to certified 8.370%. Due to drastic improvement in efficiency and easy utilization, this method opens new opportunities for PSCs from various material systems to improve towards 10% efficiency. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. Scientific visualization for enhanced interpretation and communication of geoscientific information

    International Nuclear Information System (INIS)

    Ontario Power Generation's Deep Geologic Repository Technology Program has undertaken applied research into the application of scientific visualization technologies to: i) improve the interpretation and synthesis of complex geoscientific field data; ii) facilitate the development of defensible conceptual site descriptive models; and iii) enhance communication between multi-disciplinary site investigation teams and other stakeholders. Two scientific visualization projects are summarized that benefited from the use of the Gocad earth modelling software and were supported by an immersive virtual reality laboratory: i) the Moderately Fractured Rock experiment at the 125,000 m3 block scale; and ii) the Sub-regional Flow System Modelling Project at the 100 km2 scale. (author)

  12. Enhanced interaction between a mechanical oscillator and two coupled resonant electrical circuits

    CERN Document Server

    Dmitriev, A V

    2014-01-01

    This paper reports result of calculation and experimental realization of an electromechanical system that consists of a high-Q mechanical oscillator parametrically coupled in the manner of a capacitive transducer with a RF circuit, which is in turn inductively coupled with another RF circuit. The system operates in the resolved sideband regime when the mechanical oscillator's frequency is larger than the electrical circuits' bandwidths. Using two coupled RF circuits allowed one to enhance the interaction between them and the mechanical oscillator which is one of flexural vibrational modes of a free-edge circular silicon wafer. Such a coupled electromechanical system can be used as a high-sensitive capacitive vibration sensor.

  13. Novel start-up circuit with enhanced power-up characteristic for bandgap references

    DEFF Research Database (Denmark)

    Tuan Vu, Cao; Wisland, Dag T.; Lande, Tor Sverre;

    This paper presents a new start-up circuit for low-power bandgap reference (BGR) voltage generators. The BGR is designed for providing a stable 0.3 V power supply for application in low power wireless sensor nodes. The BGR has an enhanced power-up characteristic and demonstrates a reduction of the...... total stand-by current. Simulated results confirm that the proposed start-up circuit does not affect the performance of the BGR even though the supply voltage (VDD) is higher and has more stable power-up characteristic than the conventional start-up circuits. The new start-up circuit is designed with 65...

  14. A gap junction circuit enhances processing of coincident mechanosensory inputs.

    Science.gov (United States)

    Rabinowitch, Ithai; Chatzigeorgiou, Marios; Schafer, William R

    2013-06-01

    Electrical synapses have been shown to be important for enabling and detecting neuronal synchrony in both vertebrates and invertebrates. Hub-and-spoke circuits, in which a central hub neuron is electrically coupled to several input neurons, are an overrepresented motif in the C. elegans nervous system and may represent a conserved functional unit. The functional relevance of this configuration has been demonstrated for circuits mediating aggregation behavior and nose touch perception. Modeling approaches have been useful for understanding structurally and dynamically more complex electrical circuits. Therefore, we formulated a simple analytical model with minimal assumptions to obtain insight into the properties of the hub-and-spoke microcircuit motif. A key prediction of the model is that an active input neuron should facilitate activity throughout the network, whereas an inactive input should suppress network activity through shunting; this prediction was supported by cell ablation and in vivo neuroimaging experiments in the C. elegans nose touch circuit. Thus, the hub-and-spoke architecture may implement an analog coincidence detector enabling distinct responses to distributed and localized patterns of sensory input. PMID:23707432

  15. The Nature of Science Education for enhancing Scientific Literacy

    OpenAIRE

    Holbrook, Jack; Rannikmae, Miia

    2007-01-01

    Abstract This article explores the meaning of the nature of science education to enhance scientific literacy. It argues that the teaching approach for science education should be regarded as ?education through science, rather than ?science through education?. A model of the nature of science education is proposed having its foundations based on activity theory rather than logical positivism. This encompasses an understanding of the nature of science, with links to achievement of go...

  16. Outstanding Scientific Achievement Award Lecture 2010: Deconstructing Leptin: From Signals to Circuits

    OpenAIRE

    Myers, Martin G.

    2010-01-01

    Martin G. Myers Jr., MD, PhD, received the American Diabetes Association's prestigious 2010 Outstanding Scientific Achievement Award at the Association's 70th Scientific Sessions in Orlando, Florida, on 28 June 2010. The Outstanding Scientific Achievement Award recognizes outstanding scientific achievement in the field of diabetes, taking into consideration independence of thought and originality. Currently the Marilyn H. Vincent Professor of Diabetes Research at the University of Michigan, A...

  17. African Scientific Network: A model to enhance scientific research in developing countries

    Science.gov (United States)

    Kebede, Abebe

    2002-03-01

    Africa has over 350 higher education institutions with a variety of experiences and priorities. The primary objectives of these institutions are to produce white-collar workers, teachers, and the work force for mining, textiles, and agricultural industries. The state of higher education and scientific research in Africa have been discussed in several conferences. The proposals that are generated by these conferences advocate structural changes in higher education, North-South institutional linkages, mobilization of the African Diaspora and funding. We propose a model African Scientific Network that would facilitate and enhance international scientific partnerships between African scientists and their counterparts elsewhere. A recent article by James Lamout (Financial Times, August 2, 2001) indicates that emigration from South Africa alone costs $8.9 billion in lost human resources. The article also stated that every year 23,000 graduates leave Africa for opportunities overseas, mainly in Europe, leaving only 20,000 scientists and engineers serving over 600 million people. The International Organization for Migration states that the brain drain of highly skilled professionals from Africa is making economic growth and poverty alleviation impossible across the continent. In our model we will focus on a possible networking mechanism where the African Diaspora will play a major role in addressing the financial and human resources needs of higher education in Africa

  18. NOVEL METAMATERIAL STRUCTURES FOR MICROWAVE COMPONENT AND CIRCUIT PERFORMANCE ENHANCEMENTS

    OpenAIRE

    Decle Colin, Daniel

    2015-01-01

    In the thesis presented, three novel uni-planar left handed transmission lines based on Complementary Split Ring Resonators (CSRR) and Complementary Spiral Resonator (CSR) metamaterial particles are proposed for the first time and successfully applied for the performance enhancement of conventional coupled line filters and the design of a full scan leaky wave antenna.Based on the implementation of Complementary Split Ring Resonators (CSRR) a fully planar Composite Right left handed transmissi...

  19. Enhancing scientific reasoning by refining students' models of multivariable causality

    Science.gov (United States)

    Keselman, Alla

    Inquiry learning as an educational method is gaining increasing support among elementary and middle school educators. In inquiry activities at the middle school level, students are typically asked to conduct investigations and infer causal relationships about multivariable causal systems. In these activities, students usually demonstrate significant strategic weaknesses and insufficient metastrategic understanding of task demands. Present work suggests that these weaknesses arise from students' deficient mental models of multivariable causality, in which effects of individual features are neither additive, nor constant. This study is an attempt to develop an intervention aimed at enhancing scientific reasoning by refining students' models of multivariable causality. Three groups of students engaged in a scientific investigation activity over seven weekly sessions. By creating unique combinations of five features potentially involved in earthquake mechanism and observing associated risk meter readings, students had to find out which of the features were causal, and to learn to predict earthquake risk. Additionally, students in the instructional and practice groups engaged in self-directed practice in making scientific predictions. The instructional group also participated in weekly instructional sessions on making predictions based on multivariable causality. Students in the practice and instructional conditions showed small to moderate improvement in their attention to the evidence and in their metastrategic ability to recognize effective investigative strategies in the work of other students. They also demonstrated a trend towards making a greater number of valid inferences than the control group students. Additionally, students in the instructional condition showed significant improvement in their ability to draw inferences based on multiple records. They also developed more accurate knowledge about non-causal features of the system. These gains were maintained

  20. Enhanced Scientific Search and Retrieval from Citizen Science Tagged Data

    Science.gov (United States)

    Borne, K. D.

    2012-12-01

    The annotations and tags gathered on large datasets through Citizen Science tasks become an enhanced set of metadata terms for search and retrieval by the research community. The goals of Citizen Science projects should include acquisition of well designed metadata tags that are derived from a science-driven data model, consistent with the search requirements of the scientists who will use the data products for scientific discovery. We will describe a prototype of a Citizen Science framework, consisting of multiple tasks, aimed at generating rich annotations, both predefined and ad hoc. Specifically, the Zooniverse framework project will be presented in relation to the planned petascale LSST (Large Synoptic Survey Telescope) big data astronomy project.

  1. Sensitivity-enhanced admittance-based structure health monitoring using a higher-order resonant circuit

    International Nuclear Information System (INIS)

    An admittance-based structure health monitoring method with a higher-order resonant circuit is proposed and investigated in this paper, with the advantage of increased damage detection sensitivity. The change of the stiffness or mass in the structure due to damage can be detected by measuring the admittance from the piezoelectric transducer adhered to the host structure. It is known that designing an inductive circuitry, together with the piezoelectric capacitance, can introduce an additional resonance and yield enhanced sensitivity. In this paper, based on the electrical–mechanical analogy, a novel higher-order resonant circuit is designed and optimized to significantly improve the damage detection capability, i.e. increasing the admittance magnitude and its sensitivity to damage. Theoretical analyses and simulations are carried out. The results show that the peak admittance magnitude is increased by 74 dB for the higher-order circuit without electrical damping and 46 dB with electrical damping, when comparing with the second-order circuit system. The damage detection sensitivity is increased by 33 dB and 36 dB for a stiffness change of 0.5% and 1%, respectively, by using the proposed higher-order circuit, when comparing with the second-order circuit system, and even more when comparing with the traditional method with only a resistor. (paper)

  2. Enhancement of galloping-based wind energy harvesting by synchronized switching interface circuits

    Science.gov (United States)

    Zhao, Liya; Liang, Junrui; Tang, Lihua; Yang, Yaowen; Liu, Haili

    2015-04-01

    Galloping phenomenon has attracted extensive research attention for small-scale wind energy harvesting. In the reported literature, the dynamics and harvested power of a galloping-based energy harvesting system are usually evaluated with a resistive AC load; these characteristics might shift when a practical harvesting interface circuit is connected for extracting useful DC power. In the family of piezoelectric energy harvesting interface circuits, synchronized switching harvesting on inductor (SSHI) has demonstrated its advantage for enhancing the harvested power from existing base vibrations. This paper investigates the harvesting capability of a galloping-based wind energy harvester using SSHI interfaces, with a focus on comparing the performances of Series SSHI (S-SSHI) and Parallel SSHI (P-SSHI) with that of a standard DC interface, in terms of power at various wind speeds. The prototyped galloping-based piezoelectric energy harvester (GPEH) comprises a piezoelectric cantilever attached with a square-sectioned bluff body made of foam. Equivalent circuit model (ECM) of the GPEH is established and system-level circuit simulations with SSHI and standard interfaces are performed and validated with wind tunnel tests. The benefits of SSHI compared to standard circuit become more significant when the wind speed gets higher; while SSHI circuits lose the benefits at small wind speeds. In both experiment and simulation, the superiority of P-SSHI is confirmed while S-SSHI demands further investigation. The power output is increased by 43.75% with P-SSHI compared to the standard circuit at a wind speed of 6m/s.

  3. Mapping prefrontal circuits in vivo with manganese-enhanced magnetic resonance imaging in monkeys.

    Science.gov (United States)

    Simmons, Janine M; Saad, Ziad S; Lizak, Martin J; Ortiz, Michael; Koretsky, Alan P; Richmond, Barry J

    2008-07-23

    Manganese-enhanced magnetic resonance imaging (MEMRI) provides a powerful tool to study multisynaptic circuits in vivo and thereby to link information about neural structure and function within individual subjects. Making the best use of MEMRI in monkeys requires minimizing manganese-associated neurotoxicity, maintaining sensitivity to manganese-dependent signal changes and mapping transport throughout the brain without a priori anatomical hypotheses. Here, we performed intracortical injections of isotonic MnCl(2), comparisons of preinjection and postinjection scans, and voxelwise statistical mapping. Isotonic MnCl(2) did not cause cell death at the injection site, damage to downstream targets of manganese transport, behavioral deficits, or changes in neuronal responsiveness. We detected and mapped manganese transport throughout cortical-subcortical circuits by using voxelwise statistical comparisons of at least 10 preinjection and two postinjection scans. We were able to differentiate between focal and diffuse projection fields and to distinguish between the topography of striatal projections from orbitofrontal and anterior cingulate cortex in a single animal. This MEMRI approach provides a basis for combining circuit-based anatomical analyses with simultaneous single-unit recordings and/or functional magnetic resonance imaging in individual monkeys. Such studies will enhance our interpretations of functional data and our understanding of how neuronal activity is transformed as it propagates through a circuit. PMID:18650340

  4. Enhancement of synchronization in a hybrid neural circuit by spike timing dependent plasticity

    OpenAIRE

    Nowotny, Thomas; Zhigulin, Valentin P.; Selverston, Allan I; Abarbanel, Henry D.I.; Rabinovich, Mikhail I.

    2003-01-01

    Synchronization of neural activity is fundamental for many functions of the brain. We demonstrate that spike-timing dependent plasticity (STDP) enhances synchronization (entrainment) in a hybrid circuit composed of a spike generator, a dynamic clamp emulating an excitatory plastic synapse, and a chemically isolated neuron from the Aplysia abdominal ganglion. Fixed-phase entrainment of the Aplysia neuron to the spike generator is possible for a much wider range of frequency ratios and is more ...

  5. A quick solution, made to measure; Big scientific experiments need big circuit boards and that's where East Kilbride's D-TACQ comes in

    CERN Multimedia

    Gardner, D

    2003-01-01

    D-TACQ is a small electronics company operating in a highly-specialised market with technological expertise that few can match worldwide. It specialises in designing and manufacturing bespoke printed circuit boards (PCBs) which handle data acquisition tasks linked to scientific instrumentation and control systems (1 page).

  6. Leveraging Transcultural Enrollments to Enhance Application of the Scientific Method

    Science.gov (United States)

    Loudin, M.

    2013-12-01

    Continued growth of transcultural academic programs presents an opportunity for all of the students involved to improve utilization of the scientific method. Our own business success depends on how effectively we apply the scientific method, and so it is unsurprising that our hiring programs focus on three broad areas of capability among applicants which are strongly related to the scientific method. These are 1) ability to continually learn up-to-date earth science concepts, 2) ability to effectively and succinctly communicate in the English language, both oral and written, and 3) ability to employ behaviors that are advantageous with respect to the various phases of the scientific method. This third area is often the most difficult to develop, because neither so-called Western nor Eastern cultures encourage a suite of behaviors that are ideally suited. Generally, the acceptance of candidates into academic programs, together with subsequent high performance evidenced by grades, is a highly valid measure of continuous learning capability. Certainly, students for whom English is not a native language face additional challenges, but succinct and effective communication is an art which requires practice and development, regardless of native language. The ability to communicate in English is crucial, since it is today's lingua franca for both science and commerce globally. Therefore, we strongly support the use of frequent English written assignments and oral presentations as an integral part of all scientific academic programs. There is no question but that this poses additional work for faculty; nevertheless it is a key ingredient to the optimal development of students. No one culture has a monopoly with respect to behaviors that promote effective leveraging of the scientific method. For instance, the growing complexity of experimental protocols argues for a high degree of interdependent effort, which is more often associated with so-called Eastern than Western

  7. Enhancing the Scientific Data Delivery, Workflow and Consumption

    Science.gov (United States)

    Shrestha, S. R.; Rosencrans, M.; Collow, T. W.; Ali, K.; Zimble, D. A.; Rose, B.

    2015-12-01

    To improve scientific data and products access, usability and interoperability, NOAA offices, like the Climate Prediction Center (CPC), exploring various geospatial solutions to serve their users. As NOAA scientists develop new solutions that drive the research and implementation to improve services, it is imperative that those research outcomes (data and products) can be consumed by customers and easily integrated into customer decision processes. As such, progress is being made to leverage an interoperable data platform wherein systems can integrate with each other to support the synthesis of Climate and Weather data. In this talk, we will share an ongoing use case at CPC, demonstrating how Esri technology is being implemented to improve scientific data access, manipulation, analysis, visualization and use.

  8. Enhancing diffusion of scientific contents: Open data in Open Archives

    OpenAIRE

    Luzi, Daniela; Di Cesare, Rosa; Ruggieri, Roberta; Ricci, Marta (IRPPS-CNR); GreyNet, Grey Literature Network Service; GL13, Washington DC (US), 2011-12-05

    2011-01-01

    The free availability of data gathered during research activities is becoming one of the new challenges of the Open Access Movement. New scientific instruments and technologies used in highly collaborative fields such as molecular biology, hearth and space sciences, make it possible to collect a great amount of data under different formats. Moreover, data are often associated with tools that can aggregate them as well as with direct references to the publications - conventional or non-convent...

  9. Unraveling simultaneously enhanced open-circuit voltage and short-circuit current density in P3HT:ICBA:2,3-pyridinediol blended film based photovoltaics

    International Nuclear Information System (INIS)

    A comprehensive study was carried out to understand the simultaneous enhancement of the open-circuit voltage and short-circuit current density in P3HT:ICBA:2,3-pyridinediol blended film based photovoltaics. Femtosecond time-resolved photoluminescence, steady-state absorption spectrum, atomic force microscopy and 2D grazing-incidence wide-angle x-ray scattering were used to explore the transport characteristics of excitons. The comparatively faster exciton dissociation in the P3HT:ICBA:2,3-pyridinediol blended film is attributed to the higher mobility of the excitons in P3HT. The space-charge limited-current measurements show the carrier mobility to be more balanced in the P3HT:ICBA:2,3-pyridinediol blended film than in the P3HT:PCBM:2,3-pyridinediol blended film, which is beneficial to the photo-induced current extraction. The enhanced short-circuit current density originates from the higher exciton dissociation yield in combination with the more balanced electron-hole mobility. The results should aid the design of an organic film for high-efficiency photovoltaics. (paper)

  10. Efficient Circuit Configuration for Enhancing Resolution of 8-bit flash Analog to Digital Convertor

    Directory of Open Access Journals (Sweden)

    Gururaj Balikatti

    2012-11-01

    Full Text Available The need constantly exists for converters with higher resolution, faster conversion speeds and lower power dissipation. High speed analog to digital converters (ADCs have been based on flash architecture, because all comparators sample the analog input voltage simultaneously, this ADC is thus inherently fast. Unfortunately flash ADC requires 2N - 1 comparators to convert N bit digital code from an analog sample. This makes flash ADCs unsuitable for high resolution applications. The focus of this paper is on efficient circuit configuration to enhance resolution of available 8-bit flash ADC, while maintaining number of comparators only 256 for 12 bit conversion. This technique optimizes the number of comparator requirements. In this approach, an 8-bit flash ADC partitions the analog input range into 256 quantization cells, separated by 255 boundary points. An 8-bit binary code 00000000 to 11111111 is assigned to each cell. The Microcontroller decides within which cell the input sample lies and assigns a 12-bit binary center code 000000000000 to 111111111111 according to the cell value. The exact 12-bit digital code is obtained by successive approximation technique. In this paper the focus will be on all-around efficient circuit for enhancing resolution of 8-bit Flash ADC. It is shown that by adopting this configuration, we can obtain 12-bit digital data just using 256 comparators. Therefore this technique is best suitable when high speed combined with high resolution is required. An experimental prototype of proposed 12-bit ADC was implemented using Philips P89V51RD2BN Microcontroller. Use of Microcontroller has greatly reduced the hardware requirement and cost. An ADC result of 12-bit prototype is presented. The results show that the ADC exhibits a maximum DNL of 0.52LSB and a maximum INL of 0.55LSB.

  11. Soil scientific supervision of 220/38 kV cable circuits of the power station 'Eemscentrale' in the Dutch province Groningen: Part 2

    International Nuclear Information System (INIS)

    Recently, five underground cable circuits were completed at the site of the EPON (an energy utility for the north-eastern part of the Netherlands) title power station, consisting of two 220 kV and two 380 kV connections with a total length of 24 km. In a previous article, attention is paid to theoretical aspects of heat transfer of cables for underground electricity transport, the research method of the soil scientific survey, and the results of the survey for the design of the cable connection, to be made by NKF (cable manufacturer) and for the final execution of the cable design. In this article attention will be paid to soil scientific marginal conditions and soil scientific supervision during the realization. 1 fig., 2 tabs., 2 refs

  12. Shape optimization of a printed-circuit heat exchanger to enhance thermal-hydraulic performance

    International Nuclear Information System (INIS)

    Printed circuit heat exchanger (PCHE) is recently considered as a recuperator for the high temperature gas cooled reactor. In this work, the zigzag-channels of a PCHE have been optimized by using three-dimensional Reynolds-Averaged Navier-Stokes (RANS) analysis and response surface approximation (RSA) modeling technique to enhance thermal-hydraulic performance. Shear stress transport turbulence model is used as a turbulence closure. The objective function is defined as a linear combination of the functions related to heat transfer and friction loss of the PCHE, respectively. Three geometric design variables viz., the ratio of the radius of the fillet to hydraulic diameter of the channels, the ratio of wavelength to hydraulic diameter of the channels, and the ratio of wave height to hydraulic diameter of the channels, are used for the optimization. Design points are selected through Latin-hypercube sampling. The optimal design is determined through the RSA model which uses RANS derived calculations at the design points. The results show that the optimum shape enhances considerably the thermal-hydraulic performance than a reference shape. (authors)

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

    Science.gov (United States)

    Lawanto, Oenardi; Santoso, Harry

    2013-01-01

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

  14. Interface Modification of Dye-sensitized Solar Cells with Pivalic Acid to Enhance the Open-circuit Voltage

    KAUST Repository

    Li, Xin

    2009-01-01

    Pivalic acid (PVA) was used as a new coadsorbent to dye-sensitized solar cells (DSCs) to modify the interface between the TiO2 films and electrolyte. The addition of PVA improved the light-to-electricity conversion efficiency of devices by 8% by enhancing the open-circuit voltage. Copyright © 2009 The Chemical Society of Japan.

  15. Data Democracy and Decision Making: Enhancing the Use and Value of Geospatial Data and Scientific Information

    Science.gov (United States)

    Shapiro, C. D.

    2014-12-01

    Data democracy is a concept that has great relevance to the use and value of geospatial data and scientific information. Data democracy describes a world in which data and information are widely and broadly accessible, understandable, and useable. The concept operationalizes the public good nature of scientific information and provides a framework for increasing benefits from its use. Data democracy encompasses efforts to increase accessibility to geospatial data and to expand participation in its collection, analysis, and application. These two pillars are analogous to demand and supply relationships. Improved accessibility, or demand, includes increased knowledge about geospatial data and low barriers to retrieval and use. Expanded participation, or supply, encompasses a broader community involved in developing geospatial data and scientific information. This pillar of data democracy is characterized by methods such as citizen science or crowd sourcing.A framework is developed for advancing the use of data democracy. This includes efforts to assess the societal benefits (economic and social) of scientific information. This knowledge is critical to continued monitoring of the effectiveness of data democracy implementation and of potential impact on the use and value of scientific information. The framework also includes an assessment of opportunities for advancing data democracy both on the supply and demand sides. These opportunities include relatively inexpensive efforts to reduce barriers to use as well as the identification of situations in which participation can be expanded in scientific efforts to enhance the breadth of involvement as well as expanding participation to non-traditional communities. This framework provides an initial perspective on ways to expand the "scientific community" of data users and providers. It also describes a way forward for enhancing the societal benefits from geospatial data and scientific information. As a result, data

  16. High frequency equivalent circuit of GaAs depletion and enhancement FETs for large signal modelling

    OpenAIRE

    Berroth, Manfred; Bosch, Roland

    1990-01-01

    For the design of digital circuits as well as for power amplifiers, the nonlinear modelling of GaAs FETs is a necessity. We use an extended equivalent circuit, which takes into account the gate current of positive biased transistors as well as the symmetrical nature of the devices at low drain voltages. A fast method to determine the elements of the equivalent circuit from measured S-parameters is presented which delivers for the first time good agreement for all operating points. A valid lar...

  17. Linking neuroscientific research on decision making to the educational context of novice students assigned to a multiple-choice scientific task involving common misconceptions about electrical circuits

    Directory of Open Access Journals (Sweden)

    Patrice ePotvin

    2014-01-01

    Full Text Available Functional magnetic resonance imaging was used to identify the brain-based mechanisms of uncertainty and certainty associated with answers to multiple-choice questions involving common misconceptions about electric circuits. Twenty-two (22 scientifically novice participants (humanities and arts college students were asked, in an fMRI study, whether or not they thought the light bulbs in images presenting electric circuits were lighted up correctly, and if they were certain or uncertain of their answers. When participants reported that they were unsure of their responses, analyses revealed significant activations in brain areas typically involved in uncertainty (anterior cingulate cortex, anterior insula cortex, and superior/dorsomedial frontal cortex and in the left middle/superior temporal lobe. Certainty was associated with large bilateral activations in the occipital and parietal regions usually involved in visuospatial processing. Correct-and-certain answers were associated with activations that suggest a stronger mobilization of visual attention resources when compared to incorrect-and-certain answers. These findings provide insights into brain-based mechanisms of uncertainty that are activated when common misconceptions, identified as such by science education research literature, interfere in decision making in a school-like task. We also discuss the implications of these results from an educational perspective.

  18. Visualization: A pathway to enhanced scientific productivity in the expanding missions of Space and Earth Sciences

    Science.gov (United States)

    Szuszczewicz, E. P.

    1995-01-01

    The movement toward the solution of problems involving large-scale system science, the ever-increasing capabilities of three-dimensional, time-dependent numerical models, and the enhanced capabilities of 'in situ' and remote sensing instruments bring a new era of scientific endeavor that requires an important change in our approach to mission planning and the task of data reduction and analysis. Visualization is at the heart of the requirements for a much-needed enhancement in scientific productivity as we face these new challenges. This article draws a perspective on the problem as it crosses discipline boundaries from solar physics to atmospheric and ocean sciences. It also attempts to introduce visualization as a new approach to scientific discovery and a tool which expedites and improves our insight into physically complex problems. A set of simple illustrations demonstrates a number of visualization techniques and the discussion emphasizes the trial-and-error and search-and-discover modes that are necessary for the techniques to reach their full potential. Further discussions also point to the importance of integrating data access, management, mathematical operations, and visualization into a single system. Some of the more recent developments in this area are reviewed.

  19. [AGIKO (Clinical Research Fellow); a training model aimed at enhancement of clinical scientific research].

    Science.gov (United States)

    van Rees-Wortelboer, M M; Lamberts, S W; Klasen, E C

    1997-06-21

    The enhancement of clinical scientific research in the Netherlands is being stimulated to a substantial extent by the introduction and stimulation of a training model aimed at the combined training of physicians to both a general practitioner or specialist and a clinical researcher, the AGIKO (Clinical Research Fellow). The model has been recognized by the Central College for Recognition and Registration of Medical Specialists. Extra stimulation by the section Medical Sciences of the Netherlands Organization for Scientific Research (MW-NWO) makes it possible to appoint AGIKOs on second or third flows of funds but also within the first flow of funds. During the last two years, 25 AGIKO applications from ten medical specialisms have been approved. The AGIKO model may help to meet (expected) needs for future clinical-medical research workers in specific research areas. PMID:9380169

  20. Electrochemical approach to enhance the open-circuit voltage (Voc) of dye-sensitized solar cells (DSSCs)

    International Nuclear Information System (INIS)

    The net enhancement of open-circuit voltage (Voc) of dye-sensitized solar cells (DSSCs) was achieved with the novel electrolyte composed of interhalogen based binary-redox couples without regard to the choice of sensitizers. The interhalogen ion, I2Br−, was formed in the conventional iodine-based electrolyte by both chemically and electrochemically and it was found to produce an extra redox pair, (I−, Br−)/I2Br−, with new energy state at a more positive potential than that of I−/I3−. The Fermi level of the electrolyte shifted positively by the weighted-average of the two redox systems. It induced the increase of Voc up to 30, 60, and 50 mV for cis-diisothiocyanato-bis(2,2′-bipyridyl-4,4′-dicarboxylato) ruthenium(II) bis(tetrabutylammonium) (N719), cis-dicyano-bis(2,2′-bipyridyl-4,4′-dicarboxylic acid) ruthenium(II) (Ruthenizer 505 or Ru505), and 2′,4′,5′,7′-tetrabromofluorescein (eosin Y) dyes, respectively, without affecting the short circuit current much. It corresponded to the enhancement of the overall power conversion efficiency (η) up to 8, 14, and 13%, respectively. Moreover, the degree of enhancement of Voc was controllable by varying [I2Br−] since the higher the contribution of [I2Br−] the more positive shift in the energy level of the binary redox couples

  1. Guanidinium: A Route to Enhanced Carrier Lifetime and Open-Circuit Voltage in Hybrid Perovskite Solar Cells.

    Science.gov (United States)

    Marco, Nicholas De; Zhou, Huanping; Chen, Qi; Sun, Pengyu; Liu, Zonghao; Meng, Lei; Yao, En-Ping; Liu, Yongsheng; Schiffer, Andy; Yang, Yang

    2016-02-10

    Hybrid perovskites have shown astonishing power conversion efficiencies owed to their remarkable absorber characteristics including long carrier lifetimes, and a relatively substantial defect tolerance for solution-processed polycrystalline films. However, nonradiative charge carrier recombination at grain boundaries limits open circuit voltages and consequent performance improvements of perovskite solar cells. Here we address such recombination pathways and demonstrate a passivation effect through guanidinium-based additives to achieve extraordinarily enhanced carrier lifetimes and higher obtainable open circuit voltages. Time-resolved photoluminescence measurements yield carrier lifetimes in guanidinium-based films an order of magnitude greater than pure-methylammonium counterparts, giving rise to higher device open circuit voltages and power conversion efficiencies exceeding 17%. A reduction in defect activation energy of over 30% calculated via admittance spectroscopy and confocal fluorescence intensity mapping indicates successful passivation of recombination/trap centers at grain boundaries. We speculate that guanidinium ions serve to suppress formation of iodide vacancies and passivate under-coordinated iodine species at grain boundaries and within the bulk through their hydrogen bonding capability. These results present a simple method for suppressing nonradiative carrier loss in hybrid perovskites to further improve performances toward highly efficient solar cells. PMID:26790037

  2. Data management, code deployment, and scientific visualization to enhance scientific discovery in fusion research through advanced computing

    International Nuclear Information System (INIS)

    The long-term vision of the Fusion Collaboratory described in this paper is to transform fusion research and accelerate scientific understanding and innovation so as to revolutionize the design of a fusion energy source. The Collaboratory will create and deploy collaborative software tools that will enable more efficient utilization of existing experimental facilities and more effective integration of experiment, theory, and modeling. The computer science research necessary to create the Collaboratory is centered on three activities: security, remote and distributed computing, and scientific visualization. It is anticipated that the presently envisioned Fusion Collaboratory software tools will require 3 years to complete

  3. Enhancing Seismic Calibration Research Through Software Automation and Scientific Information Management

    Energy Technology Data Exchange (ETDEWEB)

    Ruppert, S D; Dodge, D A; Elliott, A B; Ganzberger, M D; Hauk, T F; Matzel, E M

    2005-07-12

    The National Nuclear Security Administration (NNSA) Ground-Based Nuclear Explosion Monitoring Research and Engineering (GNEM R&E) Program has made significant progress enhancing the process of deriving seismic calibrations and performing scientific integration with automation tools. We present an overview of our software automation and scientific data management efforts and discuss frameworks to address the problematic issues of very large datasets and varied formats utilized during seismic calibration research. The software and scientific automation initiatives directly support the rapid collection of raw and contextual seismic data used in research, provide efficient interfaces for researchers to measure/analyze data, and provide a framework for research dataset integration. The automation also improves the researchers ability to assemble quality controlled research products for delivery into the NNSA Knowledge Base (KB). The software and scientific automation tasks provide the robust foundation upon which synergistic and efficient development of, GNEM R&E Program, seismic calibration research may be built. The task of constructing many seismic calibration products is labor intensive and complex, hence expensive. However, aspects of calibration product construction are susceptible to automation and future economies. We are applying software and scientific automation to problems within two distinct phases or ''tiers'' of the seismic calibration process. The first tier involves initial collection of waveform and parameter (bulletin) data that comprise the ''raw materials'' from which signal travel-time and amplitude correction surfaces are derived and is highly suited for software automation. The second tier in seismic research content development activities include development of correction surfaces and other calibrations. This second tier is less susceptible to complete automation, as these activities require the judgment

  4. ENHANCING SEISMIC CALIBRATION RESEARCH THROUGH SOFTWARE AUTOMATION AND SCIENTIFIC INFORMATION MANAGEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Ruppert, S D; Dodge, D A; Ganzberger, M D; Hauk, T F; Matzel, E M

    2007-07-06

    The National Nuclear Security Administration (NNSA) Ground-Based Nuclear Explosion Monitoring Research and Engineering (GNEM R&E) Program at LLNL has made significant progress enhancing the process of deriving seismic calibrations and performing scientific integration, analysis, and information management with software automation tools. Several achievements in schema design, data visualization, synthesis, and analysis were completed this year. Our tool efforts address the problematic issues of very large datasets and varied formats encountered during seismic calibration research. As data volumes have increased, scientific information management issues such as data quality assessment, ontology mapping, and metadata collection that are essential for production and validation of derived calibrations have negatively impacted researchers abilities to produce products. New information management and analysis tools have resulted in demonstrated gains in efficiency of producing scientific data products and improved accuracy of derived seismic calibrations. Significant software engineering and development efforts have produced an object-oriented framework that provides database centric coordination between scientific tools, users, and data. Nearly a half billion parameters, signals, measurements, and metadata entries are all stored in a relational database accessed by an extensive object-oriented multi-technology software framework that includes elements of stored procedures, real-time transactional database triggers and constraints, as well as coupled Java and C++ software libraries to handle the information interchange and validation requirements. Significant resources were applied to schema design to enable recording of processing flow and metadata. A core capability is the ability to rapidly select and present subsets of related signals and measurements to the researchers for analysis and distillation both visually (JAVA GUI client applications) and in batch mode

  5. Scientific objectives of the Canadian CASSIOPE enhanced polar outflow probe (e-POP) small satellite mission

    International Nuclear Information System (INIS)

    Complete text of publication follows. CASSIOPE is a Canadian small satellite scheduled for launch in 2010 into a polar orbit (300 x 1500 km, 80deg inclination). The scientific objective of its Enhanced Polar Outflow Probe (e-POP) payload is to make observations of mesoscale and microscale space weather processes in the topside polar ionosphere at the highest-possible resolution, specifically to study the microscale characteristics of plasma outflow and related plasma processes, the occurrence morphology of neutral escape, and the effects of auroral currents on plasma outflow and those of plasma microstructures on radio propagation. The e-POP payload will carry a suite of 8 scientific instruments, including imaging plasma and neutral particle sensors, magnetometers, dual-frequency GPS receivers, CCD cameras, a radio wave receiver and a beacon transmitter. It will utilize the large (terabyte) data storage and downlink capacity onboard to support the planned high-resolution observations. The imaging plasma sensors will measure particle distributions and the magnetometers will measure field-aligned currents on the time scale of 10 ms and spatial scale of ∼100 m. The CCD cameras will perform auroral imaging on the time scale of 100 ms. The GPS and radio-wave receivers will perform imaging studies of the ionosphere in conjunction with ground-based radars, and the beacon transmitter in conjunction with ground receiving stations. In this paper, we discuss the scientific objectives of the e-POP mission and the planned investigations of plasma outflow, wave propagation, and related space weather processes.

  6. Photon management for enhanced open-circuit voltage in nanostructured solar cells

    Science.gov (United States)

    Sandhu, S.; Yu, Z.; Fan, S.

    2015-10-01

    We review the recent progress on using pure photonic engineering for voltage enhancement of nanostructured solar cells. These works use a detailed balance analysis for the current-voltage modeling of their devices, while taking into account of intrinsic material nonidealities to determine their fundamental limiting performances. The physics of voltage enhancement in these nanostructures is elucidated and shown to be related to the suppression of thermal emission in the immediate vicinity of the material electronic bandgap. We also review a recent work on using thermal emission suppresion in a single material tandem cell configuration to overcome the Shockley-Queisser limit.

  7. Study on Metals Recovery from -0.074 mm Printed Circuit Boards by Enhanced Gravity Separation

    Institute of Scientific and Technical Information of China (English)

    赵跃民; 温雪峰; 施红霞; 焦红光; 陶有俊

    2006-01-01

    Nowadays study on reutilization of discarded printed circuit boards (PCBs) has great significance for achieving secondary resources recycling and preventing environmental pollution. Physical methods show great potential and advantages on discarded PCBs reutilization, compared with chemical and biological methods. However for the particles of -0.074 mm PCBs, little work has been done in the past because of lower separation efficiency and recovery. In this work, the conundrum of-0.074 mm PCBs reutilization was resolved successfully with the help of Falcon concentrator. Separation mechanism for fine particles with different mass densities in a Falcon centrifugal concentrator was analyzed. The main factors such as magnitude of rotation frequency (centrifugal acceleration), anti-charge water pressure and feeding concentration were studied,and interaction of different factors was analyzed using Design-Expert software. The experimental results show that metals grade of-0.074 mm PCBs and integration efficiency were obtained as 76.89% and 80.77% respectively when feeding concentration was 40 g/L with water pressure of 0.01 MPa and rotation frequency of 50 Hz.

  8. Enhancing innovation between scientific and indigenous knowledge: pioneer NGOs in India

    Directory of Open Access Journals (Sweden)

    Laplante Julie

    2009-10-01

    Full Text Available Abstract Background Until recently, little attention has been paid to local innovation capacity as well as management practices and institutions developed by communities and other local actors based on their traditional knowledge. This paper doesn't focus on the results of scientific research into innovation systems, but rather on how local communities, in a network of supportive partnerships, draw knowledge for others, combine it with their own knowledge and then innovate in their local practices. Innovation, as discussed in this article, is the capacity of local stakeholders to play an active role in innovative knowledge creation in order to enhance local health practices and further environmental conservation. In this article, the innovative processes through which this capacity is created and reinforced will be defined as a process of "ethnomedicine capacity". Methods The field study undertaken by the first author took place in India, in the State of Tamil Nadu, over a period of four months in 2007. The data was collected through individual interviews and focus groups and was complemented by participant observations. Results The research highlights the innovation capacity related to ethnomedical knowledge. As seen, the integration of local and scientific knowledge is crucial to ensure the practices anchor themselves in daily practices. The networks created are clearly instrumental to enhancing the innovation capacity that allows the creation, dissemination and utilization of 'traditional' knowledge. However, these networks have evolved in very different forms and have become entities that can fit into global networks. The ways in which the social capital is enhanced at the village and network levels are thus important to understand how traditional knowledge can be used as an instrument for development and innovation. Conclusion The case study analyzed highlights examples of innovation systems in a developmental context. They demonstrate that

  9. ENHANCING SEISMIC CALIBRATION RESEARCH THROUGH SOFTWARE AUTOMATION AND SCIENTIFIC INFORMATION MANAGEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Ruppert, S; Dodge, D A; Ganzberger, M D; Hauk, T F; Matzel, E M

    2008-07-03

    The National Nuclear Security Administration (NNSA) Ground-Based Nuclear Explosion Monitoring Research and Development (GNEMRD) Program at LLNL continues to make significant progress enhancing the process of deriving seismic calibrations and performing scientific integration, analysis, and information management with software automation tools. Our tool efforts address the problematic issues of very large datasets and varied formats encountered during seismic calibration research. New information management and analysis tools have resulted in demonstrated gains in efficiency of producing scientific data products and improved accuracy of derived seismic calibrations. The foundation of a robust, efficient data development and processing environment is comprised of many components built upon engineered versatile libraries. We incorporate proven industry 'best practices' throughout our code and apply source code and bug tracking management as well as automatic generation and execution of unit tests for our experimental, development and production lines. Significant software engineering and development efforts have produced an object-oriented framework that provides database centric coordination between scientific tools, users, and data. Over a half billion parameters, signals, measurements, and metadata entries are all stored in a relational database accessed by an extensive object-oriented multi-technology software framework that includes stored procedures, real-time transactional database triggers and constraints, as well as coupled Java and C++ software libraries to handle the information interchange and validation requirements. Significant resources were applied to schema design to enable management of processing methods and station parameters, responses and metadata. This allowed for the development of merged ground-truth (GT) data sets compiled by the NNSA labs and AFTAC that include hundreds of thousands of events and tens of millions of arrivals. The

  10. Microrover Nanokhod enhancing the scientific output of the ExoMars Lander

    Science.gov (United States)

    Klinkner, Sabine; Bernhardt, Bodo; Henkel, Hartmut; Rodionov, Daniel; Klingelhoefer, Goestar

    The Nanokhod rover is a small and mobile exploration platform carrying out in-situ exploration by transporting and operating scientific instruments to interesting samples beyond the landing point. The microrover has a volume of 160x65x250mm (3) it weighs 3.2kg including a payload mass of 1kg and it has a peak power of 5W. The scientific model payload of the rover is a Geochemistry Instrument Package Facility (GIPF), which analyses the chemical and mineralogical composition of planetary surfaces. It consists of: An Alpha-Particle-Xray-spectrometer, a Mößbauer spectrometer and a miniature imaging system. The amount of science which can be performed within the operating range of the lander is limited since there are only few reachable, scientific interesting objects. By travelling to new sites with the aid of a microrover, the additional reach enhances the mission output and provides a significant increase in scientific return. The implementation of the Nanokhod rover on the ExoMars Lander increases its operating range by a radius of several meters, requiring only a minor mass impact of few kilograms. The Nanokhod rover is a tethered vehicle based on a Russian concept. It stays connected to the Lander via thin cables throughout the mission. This connection is used for power supply to the rover as well as the transmission of commands and scientific data. This solution minimises the communication unit and eliminates the power subsystems on the rover side, saving valuable mass and thus improving the payload to system mass ratio. By removing the power storage subsystem on the rover side, the mobile system provides a high thermal robustness and allows the system to easily survive Martian nights. The locomotion of the rover is provided by tracks. This is the optimised locomotion method on a soft and sandy surface for such a small, low-mass system, allowing even to negotiate steep slopes. The tracks enable a large contact surface of the vehicle, thus reducing its contact

  11. Enhancing Scientific Collaboration, Transparency, and Public Access: Utilizing the Second Life Platform to Convene a Scientific Conference in 3-D Virtual Space

    Science.gov (United States)

    McGee, B. W.

    2006-12-01

    Recent studies reveal a general mistrust of science as well as a distorted perception of the scientific method by the public at-large. Concurrently, the number of science undergraduate and graduate students is in decline. By taking advantage of emergent technologies not only for direct public outreach but also to enhance public accessibility to the science process, it may be possible to both begin a reversal of popular scientific misconceptions and to engage a new generation of scientists. The Second Life platform is a 3-D virtual world produced and operated by Linden Research, Inc., a privately owned company instituted to develop new forms of immersive entertainment. Free and downloadable to the public, Second Life offers an imbedded physics engine, streaming audio and video capability, and unlike other "multiplayer" software, the objects and inhabitants of Second Life are entirely designed and created by its users, providing an open-ended experience without the structure of a traditional video game. Already, educational institutions, virtual museums, and real-world businesses are utilizing Second Life for teleconferencing, pre-visualization, and distance education, as well as to conduct traditional business. However, the untapped potential of Second Life lies in its versatility, where the limitations of traditional scientific meeting venues do not exist, and attendees need not be restricted by prohibitive travel costs. It will be shown that the Second Life system enables scientific authors and presenters at a "virtual conference" to display figures and images at full resolution, employ audio-visual content typically not available to conference organizers, and to perform demonstrations or premier three-dimensional renderings of objects, processes, or information. An enhanced presentation like those possible with Second Life would be more engaging to non- scientists, and such an event would be accessible to the general users of Second Life, who could have an

  12. Cognitive enhancers versus addictive psychostimulants: The good and bad side of dopamine on prefrontal cortical circuits.

    Science.gov (United States)

    Bisagno, Veronica; González, Betina; Urbano, Francisco J

    2016-07-01

    In this review we describe how highly addictive psychostimulants such as cocaine and methamphetamine actions might underlie hypoexcitabilty in frontal cortical areas observed in clinical and preclinical models of psychostimulant abuse. We discuss new mechanisms that describe how increments on synaptic dopamine release are linked to reduce calcium influx in both pre and postsynaptic compartments on medial PFC networks, therefore modulating synaptic integration and information. Sustained DA neuromodulation by addictive psychostimulants can "lock" frontal cortical networks in deficient states. On the other hand, other psychostimulants such as modafinil and methylphenidate are considered pharmacological neuroenhancement agents that are popular among healthy people seeking neuroenhancement. More clinical and preclinical research is needed to further clarify mechanisms of actions and physiological effects of cognitive enhancers which show an opposite pattern compared to chronic effect of addictive psychostimulants: they appear to increase cortical excitability. In conclusion, studies summarized here suggest that there is frontal cortex hypoactivity and deficient inhibitory control in drug-addicted individuals. Thus, additional research on physiological effects of cognitive enhancers like modafinil and methylphenidate seems necessary in order to expand current knowledge on mechanisms behind their therapeutic role in the treatment of addiction and other neuropsychiatric disorders. PMID:26826399

  13. Adverse health consequences of performance-enhancing drugs: an Endocrine Society scientific statement.

    Science.gov (United States)

    Pope, Harrison G; Wood, Ruth I; Rogol, Alan; Nyberg, Fred; Bowers, Larry; Bhasin, Shalender

    2014-06-01

    Despite the high prevalence of performance-enhancing drug (PED) use, media attention has focused almost entirely on PED use by elite athletes to illicitly gain a competitive advantage in sports, and not on the health risks of PEDs. There is a widespread misperception that PED use is safe or that adverse effects are manageable. In reality, the vast majority of PED users are not athletes but rather nonathlete weightlifters, and the adverse health effects of PED use are greatly underappreciated. This scientific statement synthesizes available information on the medical consequences of PED use, identifies gaps in knowledge, and aims to focus the attention of the medical community and policymakers on PED use as an important public health problem. PED users frequently consume highly supraphysiologic doses of PEDs, combine them with other PEDs and/or other classical drugs of abuse, and display additional associated risk factors. PED use has been linked to an increased risk of death and a wide variety of cardiovascular, psychiatric, metabolic, endocrine, neurologic, infectious, hepatic, renal, and musculoskeletal disorders. Because randomized trials cannot ethically duplicate the large doses of PEDs and the many factors associated with PED use, we need observational studies to collect valid outcome data on the health risks associated with PEDs. In addition, we need studies regarding the prevalence of PED use, the mechanisms by which PEDs exert their adverse health effects, and the interactive effects of PEDs with sports injuries and other high-risk behaviors. We also need randomized trials to assess therapeutic interventions for treating the adverse effects of PEDs, such as the anabolic-androgen steroid withdrawal syndrome. Finally, we need to raise public awareness of the serious health consequences of PEDs. PMID:24423981

  14. Enhancing Middle School Students' Scientific Learning and Motivation through Agent-Based Learning

    Science.gov (United States)

    Chen, C.-H.; Chou, M.-H.

    2015-01-01

    Facing students' decreasing motivation to pursue scientific study, schools and educators need to coordinate new technologies with pedagogical agents to effectively sustain or promote students' scientific learning and motivation to learn. Although the provision of pedagogical agents in student learning has been studied previously, it is not clear…

  15. Science, Eugenics and Utopia. Comparing scientific humanism and liberal eugenics on human genetic enhancement

    OpenAIRE

    Pavone, Vincenzo

    2006-01-01

    When we come across the word ‘eugenics’ it is impossible to avoid thinking of Hitler’s eugenics and racial project. The latter, however, is hardly representative of eugenics. According to the definition provided by the Routledge Encyclopedia of Philosophy, eugenics is ‘a scientific attempt to improve the human gene pool’, which includes not only genetic engineering technologies but also the practice of husbandry, which some scientific utopias proposed to extend to human reproduction already i...

  16. Measuring circuits

    CERN Document Server

    Graf, Rudolf F

    1996-01-01

    This series of circuits provides designers with a quick source for measuring circuits. Why waste time paging through huge encyclopedias when you can choose the topic you need and select any of the specialized circuits sorted by application?This book in the series has 250-300 practical, ready-to-use circuit designs, with schematics and brief explanations of circuit operation. The original source for each circuit is listed in an appendix, making it easy to obtain additional information.Ready-to-use circuits.Grouped by application for easy look-up.Circuit source listings

  17. Circuit theory

    International Nuclear Information System (INIS)

    This book is divided into fourteen chapters, which deals with circuit theory of basis, sinusoidal alternating current on cycle and frequency, basics current circuit about R.L, C circuit and resonant circuit, current power, general linear circuit, inductive coupling circuit and vector locus on an alternating current bridge and mutual inductance and coupling coefficient, multiphase alternating current and method of symmetrical coordinates, non-sinusoidal alternating current, two terminal network, four terminal network, transient of circuits, distributed line circuit constant, frequency characteristic and a filter and Laplace transformation.

  18. High performance of PbSe/PbS core/shell quantum dot heterojunction solar cells: short circuit current enhancement without the loss of open circuit voltage by shell thickness control

    Science.gov (United States)

    Choi, Hyekyoung; Song, Jung Hoon; Jang, Jihoon; Mai, Xuan Dung; Kim, Sungwoo; Jeong, Sohee

    2015-10-01

    We fabricated heterojunction solar cells with PbSe/PbS core shell quantum dots and studied the precisely controlled PbS shell thickness dependency in terms of optical properties, electronic structure, and solar cell performances. When the PbS shell thickness increases, the short circuit current density (JSC) increases from 6.4 to 11.8 mA cm-2 and the fill factor (FF) enhances from 30 to 49% while the open circuit voltage (VOC) remains unchanged at 0.46 V even with the decreased effective band gap. We found that the Fermi level and the valence band maximum level remain unchanged in both the PbSe core and PbSe/PbS core/shell with a less than 1 nm thick PbS shell as probed via ultraviolet photoelectron spectroscopy (UPS). The PbS shell reduces their surface trap density as confirmed by relative quantum yield measurements. Consequently, PbS shell formation on the PbSe core mitigates the trade-off relationship between the open circuit voltage and the short circuit current density. Finally, under the optimized conditions, the PbSe core with a 0.9 nm thick shell yielded a power conversion efficiency of 6.5% under AM 1.5.We fabricated heterojunction solar cells with PbSe/PbS core shell quantum dots and studied the precisely controlled PbS shell thickness dependency in terms of optical properties, electronic structure, and solar cell performances. When the PbS shell thickness increases, the short circuit current density (JSC) increases from 6.4 to 11.8 mA cm-2 and the fill factor (FF) enhances from 30 to 49% while the open circuit voltage (VOC) remains unchanged at 0.46 V even with the decreased effective band gap. We found that the Fermi level and the valence band maximum level remain unchanged in both the PbSe core and PbSe/PbS core/shell with a less than 1 nm thick PbS shell as probed via ultraviolet photoelectron spectroscopy (UPS). The PbS shell reduces their surface trap density as confirmed by relative quantum yield measurements. Consequently, PbS shell formation on

  19. Ghost Hunting as a Means to Illustrate Scientific Methodology and Enhance Critical Thinking

    Science.gov (United States)

    Rockwell, Steven C.

    2012-01-01

    The increasing popularity of television shows featuring paranormal investigations has led to a renewed enthusiasm in ghost hunting activities, and belief in the paranormal in general. These shows typically feature a group of investigators who, while claiming to utilize proper scientifically correct methodologies, violate many core scientific…

  20. Enhancing the Student Experiment Experience: Visible Scientific Inquiry through a Virtual Chemistry Laboratory

    Science.gov (United States)

    Donnelly, Dermot; O'Reilly, John; McGarr, Oliver

    2013-01-01

    Practical work is often noted as a core reason many students take on science in secondary schools (high schools). However, there are inherent difficulties associated with classroom practical work that militate against scientific inquiry, an approach espoused by many science educators. The use of interactive simulations to facilitate student…

  1. The pursuit of enhanced discoverability, accessibility, and usability of scientific data in the earth sciences (Invited)

    Science.gov (United States)

    Bristol, S.

    2013-12-01

    Through the evolution of search technologies since the web was born, the problem of finding something of interest has been somewhat solved in many domains. If I want to purchase a pair of hiking boots or some other commercial product, there aren't many steps I need to go through before I can make a purchase. I might have to take time to find the best price, and I might want to do some reading to determine if the product is most suitable to my needs. But there aren't very many search and discovery steps between me and hitting the trail to break in my new boots. So, why haven't we solved this problem yet for scientific data, and why are we still talking about it? Is it that a dataset, database, data service, or some form of scientific data are all so different from a pair of shoes? Is it that there's often no direct profit motive associated with scientific data, or at least not on the same level with consumer products? Is it that government and academic institutions, the major producers of scientific data, aren't as technically adept as big commercial companies who have solved this problem in other domains? Or is it that maybe we aren't thinking about the problem in the right way, and we think our domain of scientific data is fundamentally different from all the places where the problem seems to be in the process of being solved? We definitely have issues of scale and complexity to deal with. A pair of shoes only has so many possible descriptive parameters, many of which can be shared across a wide array of other types of products. There are delivery issues as well. For those cases where we do have well established data centers and repositories, they are not exactly the same type of operation as a network of product distribution centers for a major online retailer. But perhaps there are similarities and lessons learned that can be effectively exploited to accelerate our ability to solve this problem for scientific data so that we are not struggling trying to answer

  2. Creatures of Habit: A Computational System to Enhance and Illuminate the Development of Scientific Thinking

    OpenAIRE

    Pea, Roy D.; Eisenberg, Michael; Turbak, Franklyn

    1988-01-01

    Creatures of Habit is a computer-based microworld designed to engage middle-to-high school students in the process of scientific inquiry. The system depicts a universe of interacting programmable "creatures" whose individual behavior is guided by simple rules that may model naive psychology, physical laws, chemical affinities, and other domains. Students can create or revise creature rules and explore the resulting (and often surprising) emergent behaviors within "artificial ecosystems"; or t...

  3. 50 CFR 216.41 - Permits for scientific research and enhancement.

    Science.gov (United States)

    2010-10-01

    ... under section 117 of the MMPA; (B) Contribute significantly to understanding the basic biology or... enhancement. 216.41 Section 216.41 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE...

  4. Challenges Faced by Technical and Scientific Support Organizations in Enhancing Nuclear Safety and Security. Proceedings of an international conference

    International Nuclear Information System (INIS)

    To sustain the Global Nuclear Safety and Security Framework, Member States, the IAEA, other international organizations and interested stakeholders have continued to work to strengthen each element of that framework, all of which are critical to its success. To accomplish this task, the IAEA has convened a number of major conferences to address topical issues and key strategies for consideration by the international nuclear community. Technical and scientific support organizations (TSOs) are key stakeholders that play an integral and substantive role in assisting regulatory authorities in establishing and maintaining nuclear and radiological programmes based on a firm, science based foundation for safety and security. In 2007, the first International Conference on Challenges Faced by Technical and Scientific Support Organizations in Enhancing Nuclear Safety was held in Aix-en-Provence, France, with the objective of providing TSOs from different countries, international organizations and experts with an opportunity to develop a common understanding of the responsibilities, needs and opportunities of TSOs. At the Aix-en-Provence conference, senior regulators, heads of TSOs and other stakeholders concluded that a platform for networking between TSOs for the enhancement of nuclear safety and security was needed. To help realize this vision, an International Conference on Challenges Faced by Technical and Scientific Support Organizations in Enhancing Nuclear Safety and Security was held in Tokyo from 25 to 29 October 2010. This second conference focused on international cooperation and networking among TSOs to enhance nuclear safety and security, especially in terms of their common values and their role in the regulatory process and capacity building in those Member States considering embarking on nuclear power programmes. Thirty-two panel members from across the spectrum of international nuclear activities made presentations addressing topical issues that expanded on

  5. Secure Digital Cashless Transactions with Sequence Diagrams and Spatial Circuits to Enhance the Information Assurance and Security Education

    Directory of Open Access Journals (Sweden)

    Dr. Ajantha Herath

    2012-04-01

    Full Text Available Often students have difficulties mastering cryptographic algorithms. For some time we have been developing with methods for introducing important security concepts for both undergraduate and graduate students in Information Systems, Computer Science and Engineering students. To achieve this goal, Sequence diagrams and spatial circuit derivation from equations are introduced to students. Sequence diagrams represent progression of events with time. They learn system security concepts more effectively if they know how to transform equations and high level programming language constructs into spatial circuits or special purpose hardware. This paper describes an active learning module developed to help students understand secure protocols, algorithms and modeling web applications to prevent attacks and both software and hardware implementations related to encryption. These course materials can also be used in computer organization and architecture classes to help students understand and develop special purpose circuitry for cryptographic algorithms.

  6. Reports by the Parliamentary Office for scientific and technological assessments. Tuesday, May 24, 2011. Hearing on the protection of a reactor core and critical circuit

    International Nuclear Information System (INIS)

    In the context created by the Fukushima accident, members of the French Parliament, representatives of the French nuclear safety authority (ASN), of the French Institute for radiation protection and nuclear safety (IRSN), and of the CEA describe and discuss the technical aspects and mechanism of defence-in-depth of nuclear reactors (i.e. the different and successive levels of protection aimed at ensuring the reactor integrity to be maintained, even in case of failure of a critical circuit). Then, they discuss advances and researches in the field of protection of reactors. Several research programs are evoked which concern different elements of a nuclear plants such as the fuel, the reactor, loss of cooling system, and so on; these programs are based either on experiments or on simulations

  7. Enhancing Workers’ Well-Being. Scientific and social relevance of managing stress in the workplace

    OpenAIRE

    Vignoli, Michela

    2015-01-01

    Purpose. Despite work-related stress is one of the most studied topic in organizational psychology, many aspects as for example the use of different measures (e.g. subjective and objective, qualitative and quantitative) are still under debate. According to this, in order to enhance knowledge concerning which factors and processes contribute to create healthy workplaces, this thesis is composed by four different studies aiming to understand: a) the role of relevant antecedents (e.g. leadership...

  8. Adverse Health Consequences of Performance-Enhancing Drugs: An Endocrine Society Scientific Statement

    OpenAIRE

    Pope, Harrison G.; Wood, Ruth I.; Rogol, Alan; Nyberg, Fred; Bowers, Larry; Bhasin, Shalender

    2013-01-01

    Despite the high prevalence of performance-enhancing drug (PED) use, media attention has focused almost entirely on PED use by elite athletes to illicitly gain a competitive advantage in sports, and not on the health risks of PEDs. There is a widespread misperception that PED use is safe or that adverse effects are manageable. In reality, the vast majority of PED users are not athletes but rather nonathlete weightlifters, and the adverse health effects of PED use are greatly underappreciated....

  9. Appreciation of the nature of light demands enhancement over the prevailing scientific epistemology

    Science.gov (United States)

    Roychoudhuri, Chandrasekhar

    2011-09-01

    Based on attempts to resolve the problem of various self contradictory assumptions behind the prevailing belief on single photon interference, we have analyzed the process steps behind our experimental measurements and named the process as the Interaction Process Mapping Epistemology (IPM-E). This has helped us recognize that the quantum mechanical Measurement Problem has a much universal and deeper root in nature. Our scientific theorization process suffers from a Perpetual Information Challenge (PIC), which cannot be overcome by elegant and/or sophisticated mathematical theories alone. Iterative imaginative application of IPM-E needs to be used as a metaphorical analytical continuation to fill up the missing information gaps. IPM-E has also guided us to recognize the generic NIW-principle (Non-Interaction of Waves) in the linear domain, not explicitly recognized in current books and literature. Superposition effects become manifest through light-matter interactions. Detecting dipoles gets stimulated by multiple superposed beams; it sums the simultaneous multiple stimulations into a single resultant undulation, which then guides the resultant energy exchange. The consequent transformation in the detector corresponds to observed fringes. They neither represent interference of light; nor represent selective arrival or non-arrival of photons on the detector. Photons do not possess any force of mutual interaction to generate their redistribution. Implementation of IPM-E requires us to recognize our subjective interpretation propensity with which we are burdened due to our evolutionary successes.

  10. In Situ Resource Utilization Technologies for Enhancing and Expanding Mars Scientific and Exploration Missions

    Science.gov (United States)

    Sridhar, K. R.; Finn, J. E.

    2000-07-01

    The primary objectives of the Mars exploration program are to collect data for planetary science in a quest to answer questions related to Origins, to search for evidence of extinct and extant life, and to expand the human presence in the solar system. The public and political engagement that is critical for support of a Mars exploration program is based on all of these objectives. In order to retain and to build public and political support, it is important for NASA to have an integrated Mars exploration plan, not separate robotic and human plans that exist in parallel or in sequence. The resolutions stemming from the current architectural review and prioritization of payloads may be pivotal in determining whether NASA will have such a unified plan and retain public support. There are several potential scientific and technological links between the robotic-only missions that have been flown and planned to date, and the combined robotic and human missions that will come in the future. Taking advantage of and leveraging those links are central to the idea of a unified Mars exploration plan. One such link is in situ resource utilization (ISRU) as an enabling technology to provide consumables such as fuels, oxygen, sweep and utility gases from the Mars atmosphere.

  11. A quantum-well superlattice solar cell for enhanced current output and minimized drop in open-circuit voltage under sunlight concentration

    International Nuclear Information System (INIS)

    Insertion of quantum wells (QWs) extends the absorption edge to a longer wavelength than the value of a p-i-n cell without the QWs, which is preferable for the improved current matching of a InGaP/GaAs/Ge multijunction cell. The QWs, however, reduce the open-circuit voltage (Voc) and degrade the fill factor; the latter is significant for a large number of QWs that are mandatory for sufficient light absorption. As a structure to minimize these drawbacks, a QW superlattice, a strain-balanced In0.13Ga0.86As (4.7 nm)/GaAs0.57P0.43 (3.1 nm) stack, was implemented by metalorganic vapour-phase epitaxy. It brought about an enhancement in short-circuit current density (3.0 mA cm-2) with a minimal drop in Voc(0.03 V) compared with a p-i-n cell without the superlattice. The collection efficiency of photocarriers from the wells to an external circuit was evaluated: the efficiency was above 0.95 for the superlattice, while it was below 0.8 at a large forward bias for a conventional QW cell with thicker barriers. With the fast electron-hole separation in the superlattice owing to tunnelling transport, the superlattice cell exhibited a steeper increase in Voc as a function of the sunlight concentration ratio than the conventional QW cell: at the concentration ratio of 50, the value of Voc for the superlattice cell was almost equivalent to the value of the GaAs p-i-n cell without QWs. As a possible mechanism behind such an enhancement in Voc, photocurrent generation by two-step photon absorption was observed, using the electron ground state of the superlattice as an intermediate state.

  12. Computer-aided software understanding systems to enhance confidence of scientific codes

    International Nuclear Information System (INIS)

    A unique characteristic of nuclear waste disposal is the very long time span over which the combined engineered and natural containment system must remain effective: hundreds of thousands of years. Since there is no precedent in human history for such an endeavour, simulation with the use of computers is the only means we have of forecasting possible future outcomes quantitatively. The need for reliable models and software to make such forecasts so far into the future is obvious. One of the critical elements necessary to ensure reliability is the degree of reviewability of the computer program. Among others, there are two very important reasons for this. Firstly, if there is to be any chance at all of validating the conceptual models as implemented by the computer code, peer reviewers must be able to see and understand what the program is doing. It is all but impossible to achieve this understanding by just looking at the code due to possible unfamiliarity with the language and often due as well to the length and complexity of the code. Secondly, a thorough understanding of the code is also necessary to carry out code maintenance activities which include among others, error detection, error correction and code modification for purposes of enhancing its performance, functionality or to adapt it to a changed environment. The emerging concepts of computer-aided software understanding and reverse engineering can answer precisely these needs. This paper will discuss the role they can play in enhancing the confidence one has on computer codes and several examples will be provided. Finally a brief discussion of combining state-of-art forward engineering systems with reverse engineering systems will show how powerfully they can contribute to the overall quality assurance of a computer program. (13 refs., 7 figs.)

  13. Cellular and circuit mechanisms maintain low spike co-variability and enhance population coding in somatosensory cortex

    Directory of Open Access Journals (Sweden)

    Cheng eLy

    2012-03-01

    Full Text Available The responses of cortical neurons are highly variable across repeated presentations of a stimulus. Understanding this variability is critical for theories of both sensory and motor processing, since response variance affects the accuracy of neural codes. Despite this influence, the cellular and circuit mechanisms that shape the trial-to-trial variability of population responses remain poorly understood. We used a combination of experimental and computational techniques to uncover the mechanisms underlying response variability of populations of pyramidal (E cells in layer 2/3 of rat whisker barrel cortex. Spike trains recorded from pairs of E-cells during either spontaneous activity or whisker deflected responses show similarly low levels of spiking co-variability, despite large differences in network activation between the two states. We developed network models that show how spike threshold nonlinearities dilutes E-cell spiking co-variability during spontaneous activity and low velocity whisker deflections. In contrast, during high velocity whisker deflections, cancelation mechanisms mediated by feedforward inhibition maintain low E-cell pairwise co-variability. Thus, the combination of these two mechanisms ensure low E-cell population variability over a wide range of whisker deflection velocities. Finally, we show how this active decorrelation of population variability leads to a drastic increase in the population information about whisker velocity. The canonical cellular and circuit components of our study suggest that low network variability over a broad range of neural states may generalize across the nervous system.

  14. Nonlinear compensation to enhance the input dynamic range in analog optical fiber links for the high current short circuit test

    Science.gov (United States)

    Rodriguez, Joaquin; Garduno, Raul; Velazquez, Jose; Montero, Julio

    2010-06-01

    Due to their galvanic insulation and EMI immunity properties, optical fiber links have been used in the transmitter-receiver system of an analog voltage measuring system at a high-power mid-voltage testing laboratory with a highly aggressive EMI environment. This paper introduces the application of a nonlinear compensation to limit the voltage range at the input of a voltage-controlled oscillator, which is used to produce the pulsed frequency modulation needed to transmit the analog signals over the optical fiber links. The proposed dynamic range compensation system is based on nonlinear circuits to accommodate the input range of the voltage-controlled oscillator. This approach increases the transient signal handling capabilities of the measuring system. This work demonstrates that the nonlinear compensated optical fiber approach yields a unique, electrically isolated, lightning-proof analog data transmission system, for remote measuring systems in the highly aggressive EMI environment of high-power test laboratories.

  15. Enhanced Open-Circuit Voltage in Visible Quantum Dot Photovoltaics by Engineering of Carrier-Collecting Electrodes

    KAUST Repository

    Wang, Xihua

    2011-10-26

    Colloidal quantum dots (CQDs) enable multijunction solar cells using a single material programmed using the quantum size effect. Here we report the systematic engineering of 1.6 eV PbS CQD solar cells, optimal as the front cell responsible for visible-wavelength harvesting in tandem photovoltaics. We rationally optimize each of the device\\'s collecting electrodes-the heterointerface with electron-accepting TiO2 and the deep-work-function hole-collecting MoO3 for ohmic contact-for maximum efficiency. We report an open-circuit voltage of 0.70 V, the highest observed in a colloidal quantum dot solar cell operating at room temperature. We report an AM1.5 solar power conversion efficiency of 3.5%, the highest observed in >1.5 eV bandgap CQD PV device. © 2011 American Chemical Society.

  16. Nonlinear compensation to enhance the input dynamic range in analog optical fiber links for the high current short circuit test

    International Nuclear Information System (INIS)

    Due to their galvanic insulation and EMI immunity properties, optical fiber links have been used in the transmitter–receiver system of an analog voltage measuring system at a high-power mid-voltage testing laboratory with a highly aggressive EMI environment. This paper introduces the application of a nonlinear compensation to limit the voltage range at the input of a voltage-controlled oscillator, which is used to produce the pulsed frequency modulation needed to transmit the analog signals over the optical fiber links. The proposed dynamic range compensation system is based on nonlinear circuits to accommodate the input range of the voltage-controlled oscillator. This approach increases the transient signal handling capabilities of the measuring system. This work demonstrates that the nonlinear compensated optical fiber approach yields a unique, electrically isolated, lightning-proof analog data transmission system, for remote measuring systems in the highly aggressive EMI environment of high-power test laboratories

  17. Space-Data Routers: Enhancing Deep Space communications for scientific data transmission and exploitation from Mars through Space Internetworking

    Science.gov (United States)

    Sykioti, Olga; Daglis, Ioannis; Rontogiannis, Athanasios; Tsaoussidis, Vassilis; Diamantopoulos, Sotirios

    2014-05-01

    Dissemination and exploitation of data from Deep Space missions, such as planetary missions, face two major impediments: limited access capabilities due to narrow connectivity window via satellites (thus, resulting to confined scientific capacity) and lack of sufficient communication and dissemination mechanisms between deep space missions such the current missions to Mars, space data receiving centers, space-data collection centers and the end-user community. Although large quantities of data have to be transferred from deep space to the operation centers and then to the academic foundations and research centers, due to the aforementioned impediments more and more stored space data volumes remain unexploited, until they become obsolete or useless and are consequently removed. In the near future, these constraints on space and ground segment resources will rapidly increase due to the launch of new missions. The Space-Data Routers (SDR) project aims into boosting collaboration and competitiveness between the European Space Agency, the European Space Industry and the European Academic Institutions towards meeting these new challenges through Space Internetworking. Space internetworking gradually replaces or assists traditional telecommunication protocols. Future deep space operations, such as those to Mars, are scheduled to be more dynamic and flexible; many of the procedures, which are now human-operated, will become automated, interoperable and collaborative. As a consequence, space internetworking will bring a revolution in space communications. For this purpose, one of the main scientific objectives of the project is, through the examination of a specific scenario, the enhanced transmission and dissemination of Deep Space data from Mars, through unified communication channels. Specifically, the scenario involves enhanced data transmission acquired by the OMEGA sensor on-board ESA's Mars Express satellite. We consider two separate issues considering the

  18. Distortion Cancellation via Polyphase Multipath Circuits

    OpenAIRE

    Mensink, Eisse; Klumperink, Eric A.M.; Nauta, Bram

    2004-01-01

    The central question of this paper is: can we enhance the spectral purity of nonlinear circuits with the help of polyphase multipath circuits. Polyphase multipath circuits are circuits with two or more paths that exploit phase differences between the paths to cancel unwanted signals. It turns out that it is very well possible to cancel distortion products produced by a nonlinear circuit. Unfortunately, there are also some spectral components that cannot be cancelled with the polyphase multipa...

  19. Clocking Scheme for Switched-Capacitor Circuits

    DEFF Research Database (Denmark)

    Steensgaard-Madsen, Jesper

    A novel clocking scheme for switched-capacitor (SC) circuits is presented. It can enhance the understanding of SC circuits and the errors caused by MOSFET (MOS) switches. Charge errors, and techniques to make SC circuits less sensitive to them are discussed.......A novel clocking scheme for switched-capacitor (SC) circuits is presented. It can enhance the understanding of SC circuits and the errors caused by MOSFET (MOS) switches. Charge errors, and techniques to make SC circuits less sensitive to them are discussed....

  20. Clocking Scheme for Switched-Capacitor Circuits

    DEFF Research Database (Denmark)

    Steensgaard-Madsen, Jesper

    1998-01-01

    A novel clocking scheme for switched-capacitor (SC) circuits is presented. It can enhance the understanding of SC circuits and the errors caused by MOSFET (MOS) switches. Charge errors, and techniques to make SC circuits less sensitive to them are discussed.......A novel clocking scheme for switched-capacitor (SC) circuits is presented. It can enhance the understanding of SC circuits and the errors caused by MOSFET (MOS) switches. Charge errors, and techniques to make SC circuits less sensitive to them are discussed....

  1. Scientific Inquiry

    Science.gov (United States)

    National Science Teachers Association (NJ1), 2004

    2004-01-01

    Scientific inquiry reflects how scientists come to understand the natural world, and it is at the heart of how students learn. From a very early age, children interact with their environment, ask questions, and seek ways to answer those questions. Understanding science content is significantly enhanced when ideas are anchored to inquiry…

  2. Development of two-step process for enhanced biorecovery of Cu-Zn-Ni from computer printed circuit boards.

    Science.gov (United States)

    Shah, Monal B; Tipre, Devayani R; Purohit, Mamta S; Dave, Shailesh R

    2015-08-01

    Metal pollution due to the huge electronic waste (E-waste) accumulation is widespread across the globe. Extraction of copper, zinc and nickel from computer printed circuit boards (c-PCB) with a two-step bleaching process using ferric sulphate generated by Leptospirillum ferriphilum dominated consortium and the factors influencing the process were investigated in the present study. The studied factors with 10 g/L pulp density showed that pH 2.0 was optimum which resulted in 87.50-97.80% Cu-Zn-Ni extraction. Pre-treatment of PCB powder with acidified distilled water and NaCl solution showed 3.80-7.98% increase in metal extraction corresponding to 94.08% Cu, 99.80% Zn and 97.99% Ni extraction. Particle size of 75 μm for Cu and Zn while 1680 μm for Ni showed 2-folds increase in metal extraction, giving 97.35-99.80% Cu-Zn-Ni extraction in 2-6 days of reaction time. Whereas; 2.76-3.12 folds increase in Cu and Zn extraction was observed with the addition of 0.1% chelating agents. When the studies were carried out with high pulp density, ferric iron concentration of 16.57 g/L was found to be optimum for metal extraction from 75 g/L c-PCB and c-PCB addition in multiple installments resulted in 8.81-26.35% increase in metal extraction compared to single addition. The studied factors can be implemented for the scale-up aimed at faster recovery of multimetals from E-waste and thereby providing a secondary source of metal in an eco-friendly manner. PMID:25636979

  3. Look at That!: Using Madagascar Hissing Cockroaches to Develop and Enhance the Scientific Inquiry Skill of Observation in Middle School Students

    Science.gov (United States)

    Wagler, Ron

    2011-01-01

    Middle school students can develop and enhance their observation skills by participating in teacher-guided scientific inquiry (NRC 1996) activities where they observe animals that tend to act in known, predictable ways. Madagascar hissing cockroaches ("Gromphadorhina portentosa") are one such animal. This article presents beginning, intermediate,…

  4. Enhancing Visitors' Interest in Science--A Possibility or a Paradox? A Study of What Scientific Content Staff Members Focus on when Planning a New Exhibition

    Science.gov (United States)

    Davidsson, Eva

    2009-01-01

    Within the enterprise of science and technology centres there exists explicit aims and ambitions to enhance visitors' interest in and knowledge about science. Meanwhile, several researchers question the choice of the scientific content in exhibitions when arguing that a too unproblematic view of science commonly is presented. But how do staff…

  5. Circuit design for reliability

    CERN Document Server

    Cao, Yu; Wirth, Gilson

    2015-01-01

    This book presents physical understanding, modeling and simulation, on-chip characterization, layout solutions, and design techniques that are effective to enhance the reliability of various circuit units.  The authors provide readers with techniques for state of the art and future technologies, ranging from technology modeling, fault detection and analysis, circuit hardening, and reliability management. Provides comprehensive review on various reliability mechanisms at sub-45nm nodes; Describes practical modeling and characterization techniques for reliability; Includes thorough presentation of robust design techniques for major VLSI design units; Promotes physical understanding with first-principle simulations.

  6. Controllable circuit

    DEFF Research Database (Denmark)

    2010-01-01

    A switch-mode power circuit comprises a controllable element and a control unit. The controllable element is configured to control a current in response to a control signal supplied to the controllable element. The control unit is connected to the controllable element and provides the control...

  7. A Study of Power Systems Stability Enhancement Effects by Excitation Control of Superconducting Generator with High Response Excitation based on Detailed Excitation Circuit Model

    Science.gov (United States)

    Wu, Guohong; Shirato, Hideyuki

    SCG (Superconducting Generator) has a superconducting field winding, which leads to many advantages such as small size, high generation efficiency, low impedance, and so on, and be considered as one of the candidates to meet the needs of high stability and high efficiency in the future power system networks. SCG with high response excitation is especially expected to be able to enhance the transient stability of power system by its SMES (Superconducting Magnetic Energy System) effect. The SMES effect of SCG is recognized that its behaviors are dominated by the structures and controls of its excitation system. For this reason, in order to verify exactly how the SMES effect of SCG influences on the power system stability, the electrical circuits of SCG high response excitation are modeled in detail for conducting digital simulation, and its influence on excitation voltage and active power output of SCG are discussed as well. The simulation results with a typical one machine - infinite bus power system model shows that the SMES effect can be certainly obtained when its exciting power is supplied from SCG terminal bus and may considerably lead to an improvement of power system transient stability.

  8. Efficient Planar Perovskite Solar Cells with Reduced Hysteresis and Enhanced Open Circuit Voltage by Using PW12-TiO2 as Electron Transport Layer.

    Science.gov (United States)

    Huang, Chun; Liu, Canjun; Di, Yunxiang; Li, Wenzhang; Liu, Fangyang; Jiang, Liangxing; Li, Jie; Hao, Xiaojing; Huang, Haitao

    2016-04-01

    An electron transport layer is essential for effective operation of planar perovskite solar cells. In this Article, PW12-TiO2 composite was used as the electron transport layer for the planar perovskite solar cell in the device structure of fluorine-doped tin oxide (FTO)-glass/PW12-TiO2/perovskite/spiro-OMeTAD/Au. A proper downward shift of the conduction band minimum (CBM) enhanced electron extraction from the perovskite layer to the PW12-TiO2 composite layer. Consequently, the common hysteresis effect in TiO2-based planar perovskite solar cells was significantly reduced and the open circuit voltage was greatly increased to about 1.1 V. Perovskite solar cells using the PW12-TiO2 compact layer showed an efficiency of 15.45%. This work can contribute to the studies on the electron transport layer and interface engineering for the further development of perovskite solar cells. PMID:26954448

  9. EDA circuit simulation

    International Nuclear Information System (INIS)

    EDA technique is used for circuit simulation. The circuit simulation and the analysis are made for a gate circuit one-shot multivibrator. The result shows: EDA circuit simulation is very useful technique

  10. Analog and VLSI circuits

    CERN Document Server

    Chen, Wai-Kai

    2009-01-01

    Featuring hundreds of illustrations and references, this book provides the information on analog and VLSI circuits. It focuses on analog integrated circuits, presenting the knowledge on monolithic device models, analog circuit cells, high performance analog circuits, RF communication circuits, and PLL circuits.

  11. Circuits courts

    OpenAIRE

    Dubuisson-Quellier, Sophie

    2015-01-01

    Si la notion de circuit court est aujourd’hui largement reprise par les médias comme un phénomène assez typique de la fin du 20ème siècle, il convient de considérer que la vente directe est aussi ancienne que l’agriculture elle-même. Au tournant des années 2000, elle est surtout devenu un moyen, pour ceux qui la promeuvent de souligner que les distances tant géographiques qu’organisationnelles entre ceux qui produisent et ceux qui consomment sont devenus trop longues et doivent être raccourci...

  12. LOGIC CIRCUIT

    Science.gov (United States)

    Strong, G.H.; Faught, M.L.

    1963-12-24

    A device for safety rod counting in a nuclear reactor is described. A Wheatstone bridge circuit is adapted to prevent de-energizing the hopper coils of a ball backup system if safety rods, sufficient in total control effect, properly enter the reactor core to effect shut down. A plurality of resistances form one arm of the bridge, each resistance being associated with a particular safety rod and weighted in value according to the control effect of the particular safety rod. Switching means are used to switch each of the resistances in and out of the bridge circuit responsive to the presence of a particular safety rod in its effective position in the reactor core and responsive to the attainment of a predetermined velocity by a particular safety rod enroute to its effective position. The bridge is unbalanced in one direction during normal reactor operation prior to the generation of a scram signal and the switching means and resistances are adapted to unbalance the bridge in the opposite direction if the safety rods produce a predetermined amount of control effect in response to the scram signal. The bridge unbalance reversal is then utilized to prevent the actuation of the ball backup system, or, conversely, a failure of the safety rods to produce the predetermined effect produces no unbalance reversal and the ball backup system is actuated. (AEC)

  13. Short- circuit tests of circuit breakers

    OpenAIRE

    Chorovský, P.

    2015-01-01

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

  14. The Role of Interdisciplinary GIS and Data Curation Librarians in Enhancing Authentic Scientific Research in the Classroom

    OpenAIRE

    Branch, Benjamin D; Fosmire, Michael.

    2012-01-01

    Data science is a recently evolved area of scientific inquiry, where data, often collected by others, is analyzed by independent investigators to draw new conclusions. As such, data literacy needs to be incorporated into authentic research activities. The earth sciences in particular have a trove of data that resides in national data centers as well as individual investigators’ labs, which can be repurposed to provide the inputs for students to make their own inquiries into the data. With the...

  15. Building domain-specific Web collections for scientific digital libraries: A meta-search enhanced focused crawling method

    OpenAIRE

    Chau, M; Qin, J.; Zhou, Y.

    2004-01-01

    Collecting domain-specific documents from the Web using focused crawlers has been considered one of the most important strategies to build digital libraries that serve the scientific community. However, because most focused crawlers use local search algorithms to traverse the Web space, they could be easily trapped within a limited sub-graph of the Web that surrounds the starting URLs and build domain-specific collections that are not comprehensive and diverse enough to scientists and researc...

  16. Collective of mechatronics circuit

    International Nuclear Information System (INIS)

    This book is composed of three parts, which deals with mechatronics system about sensor, circuit and motor. The contents of the first part are photo sensor of collector for output, locating detection circuit with photo interrupts, photo sensor circuit with CdS cell and lamp, interface circuit with logic and LED and temperature sensor circuit. The second part deals with oscillation circuit with crystal, C-R oscillation circuit, F-V converter, timer circuit, stability power circuit, DC amp and DC-DC converter. The last part is comprised of bridge server circuit, deformation bridge server, controlling circuit of DC motor, controlling circuit with IC for PLL and driver circuit of stepping motor and driver circuit of Brushless.

  17. Cost-effectiveness of a structured progressive task-oriented circuit class training programme to enhance walking competency after stroke: The protocol of the FIT-Stroke trial

    OpenAIRE

    van de Port, Ingrid GL; Wevers, Lotte; Roelse, Hanneke; van Kats, Lenneke; Lindeman, Eline; Kwakkel, Gert

    2009-01-01

    Background Most patients who suffer a stroke experience reduced walking competency and health-related quality of life (HRQoL). A key factor in effective stroke rehabilitation is intensive, task-specific training. Recent studies suggest that intensive, patient-tailored training can be organized as a circuit with a series of task-oriented workstations. Primary aim of the FIT-Stroke trial is to evaluate the effects and cost-effectiveness of a structured, progressive task-oriented circuit class t...

  18. Circuit considerations for repetitive railguns

    Energy Technology Data Exchange (ETDEWEB)

    Honih, E.M.

    1986-01-01

    Railgun electromagnetic launchers have significant military and scientific potential. They provide direct conversion of electrical energy to projectile kinetic energy, and they offer the hope of achieving projectile velocities greatly exceeding the limits of conventional guns. With over 10 km/sec already demonstrated, railguns are attracting attention for tactical and strategic weapons systems and for scientific equation-of-state research. The full utilization of railguns will require significant improvements in every aspect of system design - projectile, barrel, and power source - to achieve operation on a large scale. This paper will review fundamental aspects of railguns, with emphasis on circuit considerations and repetitive operation.

  19. Analog circuit design designing dynamic circuit response

    CERN Document Server

    Feucht, Dennis

    2010-01-01

    This second volume, Designing Dynamic Circuit Response builds upon the first volume Designing Amplifier Circuits by extending coverage to include reactances and their time- and frequency-related behavioral consequences.

  20. Enhanced Device and Circuit-Level Performance Benchmarking of Graphene Nanoribbon Field-Effect Transistor against a Nano-MOSFET with Interconnects

    Directory of Open Access Journals (Sweden)

    Huei Chaeng Chin

    2014-01-01

    Full Text Available Comparative benchmarking of a graphene nanoribbon field-effect transistor (GNRFET and a nanoscale metal-oxide-semiconductor field-effect transistor (nano-MOSFET for applications in ultralarge-scale integration (ULSI is reported. GNRFET is found to be distinctly superior in the circuit-level architecture. The remarkable transport properties of GNR propel it into an alternative technology to circumvent the limitations imposed by the silicon-based electronics. Budding GNRFET, using the circuit-level modeling software SPICE, exhibits enriched performance for digital logic gates in 16 nm process technology. The assessment of these performance metrics includes energy-delay product (EDP and power-delay product (PDP of inverter and NOR and NAND gates, forming the building blocks for ULSI. The evaluation of EDP and PDP is carried out for an interconnect length that ranges up to 100 μm. An analysis, based on the drain and gate current-voltage (Id-Vd and Id-Vg, for subthreshold swing (SS, drain-induced barrier lowering (DIBL, and current on/off ratio for circuit implementation is given. GNRFET can overcome the short-channel effects that are prevalent in sub-100 nm Si MOSFET. GNRFET provides reduced EDP and PDP one order of magnitude that is lower than that of a MOSFET. Even though the GNRFET is energy efficient, the circuit performance of the device is limited by the interconnect capacitances.

  1. Photomultiplier blanking circuit

    Science.gov (United States)

    Mcclenahan, J. O.

    1972-01-01

    Circuit for protecting photomultiplier equipment from current surges which occur when exposed to brilliant illumination is discussed. Components of circuit and details of operation are provided. Circuit diagram to show action of blanking pulse on zener diode is included.

  2. Analog circuit design designing waveform processing circuits

    CERN Document Server

    Feucht, Dennis

    2010-01-01

    The fourth volume in the set Designing Waveform-Processing Circuits builds on the previous 3 volumes and presents a variety of analog non-amplifier circuits, including voltage references, current sources, filters, hysteresis switches and oscilloscope trigger and sweep circuitry, function generation, absolute-value circuits, and peak detectors.

  3. Open Access Centre at the Nature Research Centre: a facility for enhancement of scientific research, education and public outreach in Lithuania

    Science.gov (United States)

    Šerpenskienė, Silvija; Skridlaitė, Gražina

    2014-05-01

    etc. Applications for a grant of open access shall be received online in accordance with the established procedure via the NRC website (www.gamtostyrimai.lt). State-of-the-art equipment enables researchers to carry out up-to-date scientific research and educational projects, scientific experiments, graduation and laboratory works. Scientists, researchers and students get the opportunity to deepen their knowledge, conduct new research in the field of natural sciences, to obtain new data to be used for further studies as well as for the development of products of higher added value. Favourable conditions are created for pursuing and developing higher level scientific research, for the implementation of joint and interdisciplinary projects, for enhancing cooperation between business and public institutions as well as between those of studies and science. The implementation of the above mentioned tasks leads to the enhanced competitiveness of Lithuanian scientists and researchers and to dissemination of the high quality scientific knowledge for a society. Tens of students from different universities and researchers from other institutions are using the OAC facilities. "Pan-European coordination action on CO2 Geological Storage (CGS Europe)"; "GEO-SEAS"; "EMODNET"; "Securing the Conservation of biodiversity across Administrative Levels and spatial, temporal, and Ecological Scales (SCALES)"; "Decline Of Fraxinus excelsior in northern Europe" and other projects are being carried out at the OAC so far. This is a contribution to the Open Access Centre activities

  4. The Role of Interdisciplinary GIS and Data Curation Librarians in Enhancing Authentic Scientific Research in the Classroom

    Science.gov (United States)

    Branch, B. D.; Fosmire, M.

    2012-12-01

    Data science is a recently evolved area of scientific inquiry, where data, often collected by others, is analyzed by independent investigators to draw new conclusions. As such, data literacy needs to be incorporated into authentic research activities. The earth sciences in particular have a trove of data that resides in national data centers as well as individual investigators' labs, which can be repurposed to provide the inputs for students to make their own inquiries into the data. With the amount of data available, students can make more substantive conclusions than if relying just on data they've collected themselves. A new scientific role is that of the data scientist or data curation specialist. This person understands best practices in data and knowledge management and can translate those skills into an environment appropriate for K-20 students and teachers. In particular, data curation specialists can transform raw data into data that is audience appropriate that can be re-used. First, appropriate research data can be located, as well as foundational or baseline data (topography, political maps, etc.), and that data needs to be converted (or directions for conversion supplied) so that it can be ingested into the processing system used for the activity. Furthermore, data needs to be organized, especially as it is processed by students, and multiple versions of data created. Data also should be appropriately annotated to allow for effective sharing among students and determining reproducibility of the data. Finally, appropriate visualization of the data can be facilitated by a data curation specialist. To provide a concrete example, one of the authors developed, a data-driven authentic research project for a group of middle school students looking at water quality in a North Carolina community. Students needed to find relevant hydrologic, environmental, and political data as inputs for their project. They then collected local data to add to the standard data

  5. Sustainability issues in circuit board recycling

    DEFF Research Database (Denmark)

    Legarth, Jens Brøbech; Alting, Leo; Baldo, Gian Luca

    1995-01-01

    The resource recovery and environmental impact issues of printed circuit board recycling by secondary copper smelters are discussed. Guidelines concerning material selection for circuit board manufacture and concerning the recycling processes are given to enhance recovery efficiency and to lower...... the impacts on the external environment from recycling...

  6. Utility design of electronic circuit

    International Nuclear Information System (INIS)

    This is comprised of eleven chapters about electronic circuit design and utility circuit for electronics, which includes the point of design on electronic circuit like logical circuit, sensor circuit and power circuit, acoustic system, image system, communication system like FSK demodulation circuit, measurement and control system, appliance, operating amplifier, conversion device, counter and timer, sensor circuit, motor control such as DC motor control circuit and stepping motor drive circuit and power device like electric current control circuit.

  7. Cost-effectiveness of a structured progressive task-oriented circuit class training programme to enhance walking competency after stroke: The protocol of the FIT-Stroke trial

    OpenAIRE

    Roelse Hanneke; Wevers Lotte; van de Port Ingrid GL; van Kats Lenneke; Lindeman Eline; Kwakkel Gert

    2009-01-01

    Abstract Background Most patients who suffer a stroke experience reduced walking competency and health-related quality of life (HRQoL). A key factor in effective stroke rehabilitation is intensive, task-specific training. Recent studies suggest that intensive, patient-tailored training can be organized as a circuit with a series of task-oriented workstations. Primary aim of the FIT-Stroke trial is to evaluate the effects and cost-effectiveness of a structured, progressive task-oriented circui...

  8. Enhanced Device and Circuit-Level Performance Benchmarking of Graphene Nanoribbon Field-Effect Transistor against a Nano-MOSFET with Interconnects

    OpenAIRE

    2014-01-01

    Comparative benchmarking of a graphene nanoribbon field-effect transistor (GNRFET) and a nanoscale metal-oxide-semiconductor field-effect transistor (nano-MOSFET) for applications in ultralarge-scale integration (ULSI) is reported. GNRFET is found to be distinctly superior in the circuit-level architecture. The remarkable transport properties of GNR propel it into an alternative technology to circumvent the limitations imposed by the silicon-based electronics. Budding GNRFET, using the circui...

  9. Circuit analysis for dummies

    CERN Document Server

    Santiago, John

    2013-01-01

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

  10. Solid-state circuits

    CERN Document Server

    Pridham, G J

    2013-01-01

    Solid-State Circuits provides an introduction to the theory and practice underlying solid-state circuits, laying particular emphasis on field effect transistors and integrated circuits. Topics range from construction and characteristics of semiconductor devices to rectification and power supplies, low-frequency amplifiers, sine- and square-wave oscillators, and high-frequency effects and circuits. Black-box equivalent circuits of bipolar transistors, physical equivalent circuits of bipolar transistors, and equivalent circuits of field effect transistors are also covered. This volume is divided

  11. Challenges Faced by Regulators and Technical, Scientific and Support Organizations (TSOs) in Enhancing Nuclear Safety and Security

    International Nuclear Information System (INIS)

    Renewed interest in new reactor build programmes, not only in countries with already established nuclear programmes but also in many other countries with limited or no workforce experienced in the design, licensing, construction and operation of nuclear power plants, has resulted in a need for technical, scientific and support organizations (TSOs) to support regulatory bodies in carrying out their mandated responsibilities. The primary function of a regulatory body, such as the Federal Authority for Nuclear Regulation (FANR) in the United Arab Emirates (UAE), is to regulate the safe use of nuclear facilities and radioactive material for peaceful civilian purposes. In so doing, the regulatory body needs to provide a clear and focused approach to: safety, security and safeguards for licensing; inspection and enforcement of reactor design; construction; commissioning; operation; decommissioning; nuclear waste management activities; and the use, possession or transfer of special nuclear materials and activities within the country. Accomplishing this goal requires a highly educated, multidisciplinary, diverse workforce with significant work experience. Recognizing that it takes several decades and a lot of resources to achieve self-sufficiency, many countries, particularly emergent nuclear countries, would have to rely on TSOs to start their programmes and to carry out their oversight responsibilities. Towards that end, FANR is working closely with international counterparts, the International Atomic Energy Agency and TSOs to exchange information, expertise, industry experience and ongoing research to ensure that high levels of safety, security and safeguards are established and maintained in reactor design and operation throughout the life of the facility, and that special nuclear material within the UAE is properly documented and controlled, is not stolen, lost or diverted to any illicit or non-peaceful activities, and does not pose unreasonable radiological risk due

  12. A Flexible Power Control Method of VSC-HVDC Link for the Enhancement of Effective Short-Circuit Ratio in a Hybrid Multi-Infeed HVDC System

    DEFF Research Database (Denmark)

    Liu, Yan; Chen, Zhe

    2013-01-01

    . To evaluate the contribution of the VSC-HVDC link on the voltage stability of HMIDC system, this paper proposes an effective short circuit ratio (ESCR) calculation method. Through the calculation, the voltage support capability of the VSC-HVDC link can be quantitatively represented by the ESCR....... Furthermore, based on the calculation results, a flexible power control strategy for the VSC-HVDC link is developed to provide maximum reactive power support under grid faults. The theoretical analysis of the HMIDC system is based on the Danish transmission grid, evaluated through PSCAD simulations under...

  13. Enhanced open-circuit voltage in polymer solar cells by dithieno[3,2-b:2 ',3 '-d]pyrrole N-acylation

    OpenAIRE

    Vanormelingen, Wouter; KESTERS, Jurgen; Verstappen, Pieter; DRIJKONINGEN, Jeroen; KUDRJASOVA, Julija; Koudjina, Simplice; Liegéois, Vincent; Champagne, Benoît; Manca, Jean; Lutsen, Laurence; Vanderzande, Dirk; Maes, Wouter

    2014-01-01

    A series of low bandgap copolymers composed of N-acyl-substituted dithieno[3,2-b:2′,3′-d]pyrroles (DTPs) as the electron rich donor constituents (with various alkyl side chain patterns) combined with different electron deficient acceptor building blocks are developed for polymer solar cell applications. Due to the introduction of the N-acyl substituents, the HOMO energy levels of the push–pull copolymers decrease as compared to the N-alkyl-DTP analogues, resulting in an increased open-circuit...

  14. Modeling cortical circuits.

    Energy Technology Data Exchange (ETDEWEB)

    Rohrer, Brandon Robinson; Rothganger, Fredrick H.; Verzi, Stephen J.; Xavier, Patrick Gordon

    2010-09-01

    The neocortex is perhaps the highest region of the human brain, where audio and visual perception takes place along with many important cognitive functions. An important research goal is to describe the mechanisms implemented by the neocortex. There is an apparent regularity in the structure of the neocortex [Brodmann 1909, Mountcastle 1957] which may help simplify this task. The work reported here addresses the problem of how to describe the putative repeated units ('cortical circuits') in a manner that is easily understood and manipulated, with the long-term goal of developing a mathematical and algorithmic description of their function. The approach is to reduce each algorithm to an enhanced perceptron-like structure and describe its computation using difference equations. We organize this algorithmic processing into larger structures based on physiological observations, and implement key modeling concepts in software which runs on parallel computing hardware.

  15. Electronic devices and circuits

    CERN Document Server

    Pridham, Gordon John

    1972-01-01

    Electronic Devices and Circuits, Volume 3 provides a comprehensive account on electronic devices and circuits and includes introductory network theory and physics. The physics of semiconductor devices is described, along with field effect transistors, small-signal equivalent circuits of bipolar transistors, and integrated circuits. Linear and non-linear circuits as well as logic circuits are also considered. This volume is comprised of 12 chapters and begins with an analysis of the use of Laplace transforms for analysis of filter networks, followed by a discussion on the physical properties of

  16. The circuit designer's companion

    CERN Document Server

    Williams, Tim

    2013-01-01

    The Circuit Designer's Companion covers the theoretical aspects and practices in analogue and digital circuit design. Electronic circuit design involves designing a circuit that will fulfill its specified function and designing the same circuit so that every production model of it will fulfill its specified function, and no other undesired and unspecified function.This book is composed of nine chapters and starts with a review of the concept of grounding, wiring, and printed circuits. The subsequent chapters deal with the passive and active components of circuitry design. These topics are foll

  17. Intuitive analog circuit design

    CERN Document Server

    Thompson, Marc

    2013-01-01

    Intuitive Analog Circuit Design outlines ways of thinking about analog circuits and systems that let you develop a feel for what a good, working analog circuit design should be. This book reflects author Marc Thompson's 30 years of experience designing analog and power electronics circuits and teaching graduate-level analog circuit design, and is the ideal reference for anyone who needs a straightforward introduction to the subject. In this book, Dr. Thompson describes intuitive and ""back-of-the-envelope"" techniques for designing and analyzing analog circuits, including transistor amplifi

  18. Summary and conclusions of the conference [International conference on challenges faced by technical and scientific support organizations in enhancing nuclear safety

    International Nuclear Information System (INIS)

    . Technical and scientific support organizations (TSOs), whether part of a regulatory body or a separate organization, are gaining increased importance in providing the technical and scientific bases for decisions and activities regarding nuclear and radiation safety. International organizations such as the IAEA and the OECD Nuclear Energy Agency (OECD/NEA) also rely on the active contribution of TSOs. In the light of the important role played by TSOs, it is essential that these organizations conduct their work consistent with the highest levels of technical competence and transparency, and with the observance of ethical principles. To enhance their capabilities in these areas, TSOs need to foster cooperative activities among themselves and other relevant organizations, whether on an ad hoc basis or in the framework of regional or multilateral arrangements and institutions. Recognizing the need for TSOs to broaden their cooperation, the IAEA has sponsored this first international conference specifically addressing the role TSOs can play and the challenges they face in enhancing nuclear safety. It is hoped that the conference provided a platform for further promoting and strengthening international nuclear and radiation safety cooperation to enhance the Global Nuclear Safety Regime

  19. Enhancement of electrochemical performances for LiFePO4/C with 3D-grape-bunch structure and selection of suitable equivalent circuit for fitting EIS results

    Science.gov (United States)

    Li, Xiangfeng; Luo, Dongmei; Zhang, Xin; Zhang, Zhao

    2015-09-01

    The LiFePO4/C composite with 3D-grape-bunch structure is successfully synthesized through a novel hydrothermal method. Sucrose is used as in-situ coating carbon source, and the hydroxylated MWCNTs are used as connecting carbon wires which can be embedded into the carbon coating via self-assembling of the hydrophilic groups to form 3D-grape-bunch structure. The influences of the 3D-grape-bunch structure on the morphology, structure and electrochemical performance of the LiFePO4/C composites are investigated by XRD, SEM, TEM, BET, galvanostatic charge/discharge tests, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) tests. Especially, four kinds of the equivalent circuit models usually employed to analysis the EISs of LiFePO4 as cathode material for Li-ion battery are discussed, and the suitable equivalent circuit for fitting EIS of LiFePO4/C composite with 3D-grape-bunch structure is selected. The optimal LiFePO4/C composite with 3D-grape-bunch structure owing to its good conductive network and high graphitic degree (low ID/IG value) of residual carbon exhibits a stable and high reversible capacity of 160.5 mAh g-1 at 0.1C and 108.4 mAh g-1 even at 10.0C, and the cycling capacity retention rate reaches 99.9% over 60 cycles. Moreover, it also exhibits high conductivity, good reversibility and excellent stability in EIS and CV tests.

  20. Enhancement of open-circuit voltage on organic photovoltaic devices by Al-doped TiO{sub 2} modifying layer produced by sol–gel method

    Energy Technology Data Exchange (ETDEWEB)

    Valaski, R.; Arantes, C.; Senna, C.A.; Carôzo, Victor; Achete, C.A. [Materials Metrology Division, Instituto Nacional de Metrologia, Qualidade e Tecnologia, Xerém, Duque de Caxias 25250-020, RJ (Brazil); Cremona, M., E-mail: cremona@fis.puc-rio.br [Materials Metrology Division, Instituto Nacional de Metrologia, Qualidade e Tecnologia, Xerém, Duque de Caxias 25250-020, RJ (Brazil); Physics Department, Pontifícia Universidade Católica do Rio de Janeiro, Rio de Janeiro 22453-970, RJ (Brazil)

    2014-12-01

    Sol–gel method has shown several advantages for oxide synthesis, such as lower cost production, coating large areas, lower processing temperatures and ease insertion of doping materials. Therefore, it is attractive for production of intermediate and electrode modifying layers in organic optoelectronic devices. Herein, spin-coated aluminum-doped titanium dioxide (AlTiO{sub 2}) thin films were produced by sol–gel method onto glass and fluorine-doped tin oxide (FTO) substrates, using different Al-dopant concentrations and post-done annealing temperatures. Electrical measurements were performed in order to investigate the improvement of the TiO{sub 2} resistivity. Additionally, structural, compositional, morphological, optical and electrical properties of the optimal AlTiO{sub 2} modifying layers onto FTO substrates were probed by different techniques, and compared with those obtained from the undoped thin films produced under similar conditions. Organic photovoltaic devices (OPVs) with the structure FTO/AlTiO{sub 2}(30 nm)/C{sub 60}(50 nm)/CuPc(50 nm)/Al with an Al concentration of 0.03 M in AlTiO{sub 2} layer were produced. The insertion of AlTiO{sub 2} thin films improved the short-circuit current density (J{sub sc}) as well as the open circuit voltage (V{sub oc}) in comparison with non-modified electrode FTO based devices. This behavior is discussed in terms of induced interface phenomena as dipole formation induced by Al. - Highlights: • Easy and cheap solution-process for AlTiO{sub 2} modification of FTO electrode for OPVs • Electrical, structural and optical characterization of TiO{sub 2} layers with Al-dopant • Improvement of Voc and Jsc of inverted OPVs with AlTiO{sub 2} modified electrode.

  1. Scientific Misconduct.

    Science.gov (United States)

    Gross, Charles

    2016-01-01

    Scientific misconduct has been defined as fabrication, falsification, and plagiarism. Scientific misconduct has occurred throughout the history of science. The US government began to take systematic interest in such misconduct in the 1980s. Since then, a number of studies have examined how frequently individual scientists have observed scientific misconduct or were involved in it. Although the studies vary considerably in their methodology and in the nature and size of their samples, in most studies at least 10% of the scientists sampled reported having observed scientific misconduct. In addition to studies of the incidence of scientific misconduct, this review considers the recent increase in paper retractions, the role of social media in scientific ethics, several instructional examples of egregious scientific misconduct, and potential methods to reduce research misconduct. PMID:26273897

  2. Linear integrated circuits

    Science.gov (United States)

    Young, T.

    This book is intended to be used as a textbook in a one-semester course at a variety of levels. Because of self-study features incorporated, it may also be used by practicing electronic engineers as a formal and thorough introduction to the subject. The distinction between linear and digital integrated circuits is discussed, taking into account digital and linear signal characteristics, linear and digital integrated circuit characteristics, the definitions for linear and digital circuits, applications of digital and linear integrated circuits, aspects of fabrication, packaging, and classification and numbering. Operational amplifiers are considered along with linear integrated circuit (LIC) power requirements and power supplies, voltage and current regulators, linear amplifiers, linear integrated circuit oscillators, wave-shaping circuits, active filters, DA and AD converters, demodulators, comparators, instrument amplifiers, current difference amplifiers, analog circuits and devices, and aspects of troubleshooting.

  3. Integrated Circuits in the Introductory Electronics Laboratory

    Science.gov (United States)

    English, Thomas C.; Lind, David A.

    1973-01-01

    Discusses the use of an integrated circuit operational amplifier in an introductory electronics laboratory course for undergraduate science majors. The advantages of this approach and the implications for scientific instrumentation are identified. Describes a number of experiments suitable for the undergraduate laboratory. (Author/DF)

  4. Electrical Circuits and Water Analogies

    Science.gov (United States)

    Smith, Frederick A.; Wilson, Jerry D.

    1974-01-01

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

  5. Circuits on Cylinders

    DEFF Research Database (Denmark)

    Hansen, Kristoffer Arnsfelt; Miltersen, Peter Bro; Vinay, V

    2006-01-01

    We consider the computational power of constant width polynomial size cylindrical circuits and nondeterministic branching programs. We show that every function computed by a Pi2 o MOD o AC0 circuit can also be computed by a constant width polynomial size cylindrical nondeterministic branching...... program (or cylindrical circuit) and that every function computed by a constant width polynomial size cylindrical circuit belongs to ACC0....

  6. Electric circuits essentials

    CERN Document Server

    REA, Editors of

    2012-01-01

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

  7. Load testing circuit

    DEFF Research Database (Denmark)

    2009-01-01

    A load testing circuit a circuit tests the load impedance of a load connected to an amplifier. The load impedance includes a first terminal and a second terminal, the load testing circuit comprising a signal generator providing a test signal of a defined bandwidth to the first terminal of the load...

  8. Piezoelectric drive circuit

    Science.gov (United States)

    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.

  9. Signal sampling circuit

    NARCIS (Netherlands)

    Louwsma, Simon Minze; Vertregt, Maarten

    2010-01-01

    A sampling circuit for sampling a signal is disclosed. The sampling circuit comprises a plurality of sampling channels adapted to sample the signal in time-multiplexed fashion, each sampling channel comprising a respective track-and-hold circuit connected to a respective analogue to digital converte

  10. Signal sampling circuit

    NARCIS (Netherlands)

    Louwsma, Simon Minze; Vertregt, Maarten

    2011-01-01

    A sampling circuit for sampling a signal is disclosed. The sampling circuit comprises a plurality of sampling channels adapted to sample the signal in time-multiplexed fashion, each sampling channel comprising a respective track-and-hold circuit connected to a respective analogue to digital converte

  11. Cost-effectiveness of a structured progressive task-oriented circuit class training programme to enhance walking competency after stroke: The protocol of the FIT-Stroke trial

    Directory of Open Access Journals (Sweden)

    Roelse Hanneke

    2009-08-01

    Full Text Available Abstract Background Most patients who suffer a stroke experience reduced walking competency and health-related quality of life (HRQoL. A key factor in effective stroke rehabilitation is intensive, task-specific training. Recent studies suggest that intensive, patient-tailored training can be organized as a circuit with a series of task-oriented workstations. Primary aim of the FIT-Stroke trial is to evaluate the effects and cost-effectiveness of a structured, progressive task-oriented circuit class training (CCT programme, compared to usual physiotherapeutic care during outpatient rehabilitation in a rehabilitation centre. The task-oriented CCT will be applied in groups of 4 to 6 patients. Outcome will be defined in terms of gait and gait-related ADLs after stroke. The trial will also investigate the generalizability of treatment effects of task-oriented CCT in terms of perceived fatigue, anxiety, depression and perceived HRQoL. Methods/design The multicentre single-blinded randomized trial will include 220 stroke patients discharged to the community from inpatient rehabilitation, who are able to communicate and walk at least 10 m without physical, hands-on assistance. After discharge from inpatient rehabilitation, patients in the experimental group will receive task-oriented CCT two times a week for 12 weeks at the physiotherapy department of the rehabilitation centre. Control group patients will receive usual individual, face-to-face, physiotherapy. Costs will be evaluated by having each patient keep a cost diary for the first 24 weeks after randomisation. Primary outcomes are the mobility part of the Stroke Impact Scale (SIS-3.0 and the EuroQol. Secondary outcomes are the other domains of SIS-3.0, lower limb muscle strength, walking endurance, gait speed, balance, confidence not to fall, instrumental ADL, fatigue, anxiety, depression and HRQoL. Discussion Based on assumptions about the effect of intensity of practice and specificity of

  12. Scientific Basis for Monitored Natural Attenuation and Enhanced Passive Remediation for Chlorinated Solvents - DOE Alternative Project for Technology Acceleration Implementation Plan

    International Nuclear Information System (INIS)

    The overall Monitored Natural Attenuation and Enhanced Passive Remediation (MNA/EPR) Technology Alternative Project is narrowly focused, providing the scientific and policy support to facilitate implementing appropriate passive cleanup and cost effective monitoring strategies leading to responsible completion of active remediation activities at high risk DOE waste sites. MNA/EPR describe natural processes that mitigate exposure and risk and that are self-sustaining once implemented or require minimal adjustments to maintain functionality. The overall MNA/EPR project effort will be performed as a collaboration between DOE science and operations organizations at the target sites along with regulatory agencies, stakeholders, industry, and universities, as identified in the approved Alternative Project Plan. This plan describes the project initiation activities, individual roles and responsibilities, milestones, and budget for the project. A primary product of this project will be a collaboratively developed MNA/EPR protocol that will facilitate widespread use and acceptance. This technical protocol will be developed in collaboration with regulator agencies as input for regulation updates and guidance documents, as appropriate. This plan describes the project initiation activities, individual roles and responsibilities, milestones, and budget for the project

  13. Practical microwave circuits

    CERN Document Server

    Maas, Stephen A

    2014-01-01

    This book differentiates itself by presenting microwave and RF technology from a circuit design viewpoint, rather than a set of electromagnetic problems. The emphasis is on gaining a practical understanding of often overlooked but vital physical processes.This resource provides microwave circuit engineers with analytical techniques for understanding and designing high-frequency circuits almost entirely from a circuit point of view. Electromagnetic concepts are not avoided, but they are employed only as necessary to support circuit-theoretical ones or to describe phenomena such as radiation and

  14. Feedback in analog circuits

    CERN Document Server

    Ochoa, Agustin

    2016-01-01

    This book describes a consistent and direct methodology to the analysis and design of analog circuits with particular application to circuits containing feedback. The analysis and design of circuits containing feedback is generally presented by either following a series of examples where each circuit is simplified through the use of insight or experience (someone else’s), or a complete nodal-matrix analysis generating lots of algebra. Neither of these approaches leads to gaining insight into the design process easily. The author develops a systematic approach to circuit analysis, the Driving Point Impedance and Signal Flow Graphs (DPI/SFG) method that does not require a-priori insight to the circuit being considered and results in factored analysis supporting the design function. This approach enables designers to account fully for loading and the bi-directional nature of elements both in the feedback path and in the amplifier itself, properties many times assumed negligible and ignored. Feedback circuits a...

  15. Enhancement of open-circuit voltage and the fill factor in CdTe nanocrystal solar cells by using interface materials.

    Science.gov (United States)

    Zhu, Jiaoyan; Yang, Yuehua; Gao, Yuping; Qin, Donghuan; Wu, Hongbin; Hou, Lintao; Huang, Wenbo

    2014-09-12

    Interface states influence the operation of nanocrystal (NC) solar cell carrier transport, recombination and energetic mechanisms. In a typical CdTe NC solar cell with a normal structure of a ITO/p-CdTe NCs/n-acceptor (or without)/Al configuration, the contact between the ITO and CdTe is a non-ohm contact due to a different work function (for an ITO, the value is ~4.7 eV, while for CdTe NCs, the value is ~5.3 eV), which results in an energetic barrier at the ITO/CdTe interface and decreases the performance of the NC solar cells. This work investigates how interface materials (including Au, MoO(x) and C₆₀) affect the performance of NC solar cells. It is found that devices with interface materials have shown higher V(oc) than those without interface materials. For the case in which we used Au as an interface, we obtained a high open-circuit voltage of 0.65 V, coupled with a high fill factor (62%); this resulted in a higher energy conversion efficiency (ECE) of 5.3%, which showed a 30% increase in the ECE compared with those without the interlayer. The capacitance measurements indicate that the increased V(oc) in the case in which Au was used as the interface is likely due to good ohm contact between the Au's and the CdTe NCs' thin film, which decreases the energetic barrier at the ITO/CdTe interface. PMID:25140734

  16. Enhancement of open-circuit voltage and the fill factor in CdTe nanocrystal solar cells by using interface materials

    International Nuclear Information System (INIS)

    Interface states influence the operation of nanocrystal (NC) solar cell carrier transport, recombination and energetic mechanisms. In a typical CdTe NC solar cell with a normal structure of a ITO/p-CdTe NCs/n-acceptor (or without)/Al configuration, the contact between the ITO and CdTe is a non-ohm contact due to a different work function (for an ITO, the value is ∼4.7 eV, while for CdTe NCs, the value is ∼5.3 eV), which results in an energetic barrier at the ITO/CdTe interface and decreases the performance of the NC solar cells. This work investigates how interface materials (including Au, MoOx and C60) affect the performance of NC solar cells. It is found that devices with interface materials have shown higher Voc than those without interface materials. For the case in which we used Au as an interface, we obtained a high open-circuit voltage of 0.65 V, coupled with a high fill factor (62%); this resulted in a higher energy conversion efficiency (ECE) of 5.3%, which showed a 30% increase in the ECE compared with those without the interlayer. The capacitance measurements indicate that the increased Voc in the case in which Au was used as the interface is likely due to good ohm contact between the Au’s and the CdTe NCs’ thin film, which decreases the energetic barrier at the ITO/CdTe interface. (paper)

  17. The Biology Experimental Design Challenge: An Interactive Approach to Enhance Students’ Understanding of Scientific Inquiry in the Context of an Introductory Biology Course †

    OpenAIRE

    Olimpo, Jeffrey T.

    2015-01-01

    The scientific method serves as a procedural framework for advancing knowledge and discoveries in a number of fields, including the natural and life sciences.  Despite its essential role in these disciplines, students often perceive the scientific method to be a fact-driven, linear pursuit, rather than a dynamic process.  To address this concern, I developed the Biology Experimental Design Challenge (BEDC) game to reinforce students’ understanding of the scientific process.  Specifically, the...

  18. Case histories in scientific and pseudo-scientific mass-media communication in energy/heat production from underground (geogas storage, geothermics, hydrocarbons), in the frame of Nimby Sindrome enhancement in Europe: the proposal of a new European Direct

    Science.gov (United States)

    Quattrocchi, Fedora; Boschi, Enzo

    2014-05-01

    In the frame of energy/heat production from underground, the paper considers some European case histories and the needs of a complex and motley stakeholders community, made by scientific-industry-institutions, involved in the difficult task to study and accept (or refuse) projects strongly impacting the lived territory & underground, in densely populate countries, as Italy, in terms of appropriate public communication and sound deontological behaviour. Successively, the paper recalls years of "scientific" communication within the mass-media, highlighting the positive and negative messages, in comparison to the true and objective experimental data gathered by the real scientific work, as perceived by citizens of medium scholastic culture, which not delve the geologic disciplines, but receive simply the journalistic front-end, very often as sensationalist scoop. The authors retrace case histories of heuristic-participatory communication with the citizenship about the scientific results on challenges raised by certain technologies. The objective and rational communication is often impeded by local interests and by local journalism, which prefers to create sensationalist news more than scientific truths. This path progressively tangles as a consequence of the complex and with conflicting use of underground to produce energy (heat as gas storage, geothermical, unconventional gas exploitation, mining, etc…). Even the chain of renewables meets by now serious issues, exacerbated also by the need to start mining and drilling for the smart grids materials too (metals, rare Earths, etc..). A new text for a smart and innovative European Directivity is discussed, starting from the Italian regulatory issue. The review efforts for a "paper" on both a newspaper or a blog could be more difficult than the review a scientific paper, as a consequence of the peculiar situations behind the scenes and the conflicts of interests staying in the nest in a newspaper article or in a blog

  19. Geodiversity and geohazards of the Susa Valley (W-Alps, Italy): combining scientific research and new technologies for enhanced knowledge and proactive management of geoheritage in mountain regions

    Science.gov (United States)

    Giardino, Marco; Bacenetti, Marco; Perotti, Luigi; Giordano, Enrico; Ghiraldi, Luca; Palomba, Mauro

    2013-04-01

    Mountain regions have a range of geological and geomorphological features that make them very attractive for tourism activities. As a consequence, increased human "pressure" causes impacts on geoheritage sites and higher geomorphological risks. These effects are magnified by active geomorphic processes characterizing mountains areas, highly sensitive to climate change. In term of "human sensitivity", several sociological surveys have shown that "perceived risk", not "real risk", influences people's behavior towards natural hazards. The same approach can be applied to geodiversity and geoheritage. Based on these assumptions, we considered the possible strategic roles played by diffusion of scientific research and application of new technologies: 1) to enhance awareness, either of geodiversity or environmental dynamics and 2) to improve knowledge, both on geoheritage management and natural risk reduction. Within the activities of the "ProGEO-Piemonte Project" (Progetti d'Ateneo 2011, cofunded by Universita? degli Studi di Torino and Compagnia di San Paolo Bank Foundation), we performed a systematic review of geodiversity and natural hazards information in the Piemonte Region (NW-Italy). Then we focused our attention on the Susa Valley, an area of the Western Alps where the geoheritage is affected by very active morphodynamics, as well as by a growing tourism, after the 2006 winter Olympics. The Susa Valley became one of the 9 strategic geothematic areas have been selected to represent the geodiversity of the Piemonte region, each characterized by high potential for enhancement of public understanding of science, and recreation activities supported by local communities. Then we contributed to the awareness-raising communication strategy of the "RiskNat project" (Interreg Alcotra 2007-2013, Action A.4.3) by synthesizing geoscience knowledge on the Susa Valley and information on slope instabilities and models/prevention measures/warning systems. Visual representations

  20. Turning Crisis into Opportunity: Enhancing Student-Teachers' Understanding of Nature of Science and Scientific Inquiry through a Case Study of the Scientific Research in Severe Acute Respiratory Syndrome

    Science.gov (United States)

    Wong, Siu Ling; Hodson, Derek; Kwan, Jenny; Yung, Benny Hin Wai

    2008-01-01

    Interviews with key scientists involved in research on severe acute respiratory syndrome (SARS), together with analysis of media reports and documentaries produced during and after the SARS epidemic, revealed many interesting aspects of nature of science (NOS) and authentic scientific inquiry. This novel insight into practice in the rapidly…

  1. Exact Threshold Circuits

    DEFF Research Database (Denmark)

    Hansen, Kristoffer Arnsfelt; Podolskii, Vladimir V.

    2010-01-01

    We initiate a systematic study of constant depth Boolean circuits built using exact threshold gates. We consider both unweighted and weighted exact threshold gates and introduce corresponding circuit classes. We next show that this gives a hierarchy of classes that seamlessly interleave with the...... well-studied corresponding hierarchies defined using ordinary threshold gates. A major open problem in Boolean circuit complexity is to provide an explicit super-polynomial lower bound for depth two threshold circuits. We identify the class of depth two exact threshold circuits as a natural subclass of...... these where also no explicit lower bounds are known. Many of our results can be seen as evidence that this class is a strict subclass of depth two threshold circuits - thus we argue that efforts in proving lower bounds should be directed towards this class....

  2. Analog circuits cookbook

    CERN Document Server

    Hickman, Ian

    2013-01-01

    Analog Circuits Cookbook presents articles about advanced circuit techniques, components and concepts, useful IC for analog signal processing in the audio range, direct digital synthesis, and ingenious video op-amp. The book also includes articles about amplitude measurements on RF signals, linear optical imager, power supplies and devices, and RF circuits and techniques. Professionals and students of electrical engineering will find the book informative and useful.

  3. Analog circuit design

    CERN Document Server

    Dobkin, Bob

    2012-01-01

    Analog circuit and system design today is more essential than ever before. With the growth of digital systems, wireless communications, complex industrial and automotive systems, designers are being challenged to develop sophisticated analog solutions. This comprehensive source book of circuit design solutions aids engineers with elegant and practical design techniques that focus on common analog challenges. The book's in-depth application examples provide insight into circuit design and application solutions that you can apply in today's demanding designs. <

  4. Stochastic Switching Circuit Synthesis

    OpenAIRE

    Wilhelm, Daniel; Bruck, Jehoshua

    2009-01-01

    Shannon in his 1938 Masterpsilas Thesis demonstrated that any Boolean function can be realized by a switching relay circuit, leading to the development of deterministic digital logic. Here, we replace each classical switch with a probabilistic switch (pswitch). We present algorithms for synthesizing circuits closed with a desired probability, including an algorithm that generates optimal size circuits for any binary fraction. We also introduce a new duality property for series-parallel stocha...

  5. Electronic devices and circuits

    CERN Document Server

    Pridham, Gordon John

    1968-01-01

    Electronic Devices and Circuits, Volume 1 deals with the design and applications of electronic devices and circuits such as passive components, diodes, triodes and transistors, rectification and power supplies, amplifying circuits, electronic instruments, and oscillators. These topics are supported with introductory network theory and physics. This volume is comprised of nine chapters and begins by explaining the operation of resistive, inductive, and capacitive elements in direct and alternating current circuits. The theory for some of the expressions quoted in later chapters is presented. Th

  6. MOS integrated circuit design

    CERN Document Server

    Wolfendale, E

    2013-01-01

    MOS Integral Circuit Design aims to help in the design of integrated circuits, especially large-scale ones, using MOS Technology through teaching of techniques, practical applications, and examples. The book covers topics such as design equation and process parameters; MOS static and dynamic circuits; logic design techniques, system partitioning, and layout techniques. Also featured are computer aids such as logic simulation and mask layout, as well as examples on simple MOS design. The text is recommended for electrical engineers who would like to know how to use MOS for integral circuit desi

  7. CMOS circuits manual

    CERN Document Server

    Marston, R M

    1995-01-01

    CMOS Circuits Manual is a user's guide for CMOS. The book emphasizes the practical aspects of CMOS and provides circuits, tables, and graphs to further relate the fundamentals with the applications. The text first discusses the basic principles and characteristics of the CMOS devices. The succeeding chapters detail the types of CMOS IC, including simple inverter, gate and logic ICs and circuits, and complex counters and decoders. The last chapter presents a miscellaneous collection of two dozen useful CMOS circuits. The book will be useful to researchers and professionals who employ CMOS circu

  8. Circuits and filters handbook

    CERN Document Server

    Chen, Wai-Kai

    2003-01-01

    A bestseller in its first edition, The Circuits and Filters Handbook has been thoroughly updated to provide the most current, most comprehensive information available in both the classical and emerging fields of circuits and filters, both analog and digital. This edition contains 29 new chapters, with significant additions in the areas of computer-aided design, circuit simulation, VLSI circuits, design automation, and active and digital filters. It will undoubtedly take its place as the engineer's first choice in looking for solutions to problems encountered in the design, analysis, and behavi

  9. Timergenerator circuits manual

    CERN Document Server

    Marston, R M

    2013-01-01

    Timer/Generator Circuits Manual is an 11-chapter text that deals mainly with waveform generator techniques and circuits. Each chapter starts with an explanation of the basic principles of its subject followed by a wide range of practical circuit designs. This work presents a total of over 300 practical circuits, diagrams, and tables.Chapter 1 outlines the basic principles and the different types of generator. Chapters 2 to 9 deal with a specific type of waveform generator, including sine, square, triangular, sawtooth, and special waveform generators pulse. These chapters also include pulse gen

  10. Logic circuit and computer

    International Nuclear Information System (INIS)

    This book contains eight chapters, which are introduction of computer like history of computer, integrated circuit, micro processor and micro computer, number system and binary code such as complement and parity bit, boolean algebra and logic circuit like karnaugh map, Quine-Mclusky, and prime implicant, integrated logic circuit such as adder, subtractor, carry propagation and magnitude comparator, order logic circuit and memory like flip-flop, serial binary adder and counter, IC logic gate such as IC logic level and ECL, development of structure of micro processor and instruction and addressing mode.

  11. Security electronics circuits manual

    CERN Document Server

    MARSTON, R M

    1998-01-01

    Security Electronics Circuits Manual is an invaluable guide for engineers and technicians in the security industry. It will also prove to be a useful guide for students and experimenters, as well as providing experienced amateurs and DIY enthusiasts with numerous ideas to protect their homes, businesses and properties.As with all Ray Marston's Circuits Manuals, the style is easy-to-read and non-mathematical, with the emphasis firmly on practical applications, circuits and design ideas. The ICs and other devices used in the practical circuits are modestly priced and readily available ty

  12. Signal sampling circuit

    OpenAIRE

    Louwsma, Simon Minze; Vertregt, Maarten

    2011-01-01

    A sampling circuit for sampling a signal is disclosed. The sampling circuit comprises a plurality of sampling channels adapted to sample the signal in time-multiplexed fashion, each sampling channel comprising a respective track-and-hold circuit connected to a respective analogue to digital converter via a respective output switch. The output switch of each channel opens for a tracking time period when the track-and-hold circuit is in a tracking mode for sampling the signal, and closes for a ...

  13. Synchronizing Hyperchaotic Circuits

    DEFF Research Database (Denmark)

    Tamasevicius, Arunas; Cenys, Antanas; Namajunas, Audrius;

    1997-01-01

    Regarding possible applications to secure communications the technique of synchronizing hyperchaotic circuits with a single dynamical variable is discussed. Several specific examples including the fourth-order circuits with two positive Lyapunov exponents as well as the oscillator with a delay line...

  14. A Virtual Circuits Lab

    Science.gov (United States)

    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…

  15. Synchronizing Hyperchaotic Circuits

    DEFF Research Database (Denmark)

    Tamasevicius, Arunas; Cenys, Antanas; Namajunas, Audrius; Mykolaitis, Gytis; Lindberg, Erik

    1997-01-01

    Regarding possible applications to secure communications the technique of synchronizing hyperchaotic circuits with a single dynamical variable is discussed. Several specific examples including the fourth-order circuits with two positive Lyapunov exponents as well as the oscillator with a delay line...... characterized by multiple positive Lyapunov exponents are reviewd....

  16. Genetic circuit design automation.

    Science.gov (United States)

    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. PMID:27034378

  17. Amplifier improvement circuit

    Science.gov (United States)

    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.

  18. Microwave integrated circuits for space applications

    Science.gov (United States)

    Leonard, Regis F.; Romanofsky, Robert R.

    1991-01-01

    Monolithic microwave integrated circuits (MMIC), which incorporate all the elements of a microwave circuit on a single semiconductor substrate, offer the potential for drastic reductions in circuit weight and volume and increased reliability, all of which make many new concepts in electronic circuitry for space applications feasible, including phased array antennas. NASA has undertaken an extensive program aimed at development of MMICs for space applications. The first such circuits targeted for development were an extension of work in hybrid (discrete component) technology in support of the Advanced Communication Technology Satellite (ACTS). It focused on power amplifiers, receivers, and switches at ACTS frequencies. More recent work, however, focused on frequencies appropriate for other NASA programs and emphasizes advanced materials in an effort to enhance efficiency, power handling capability, and frequency of operation or noise figure to meet the requirements of space systems.

  19. Scientific millenarianism

    International Nuclear Information System (INIS)

    Today, for the first time, scientific concerns are seriously being addressed that span future times--hundreds, even thousands, or more years in the future. One is witnessing what the author calls scientific millenarianism. Are such concerns for the distant future exercises in futility, or are they real issues that, to the everlasting gratitude of future generations, this generation has identified, warned about and even suggested how to cope with in the distant future? Can the four potential catastrophes--bolide impact, CO2 warming, radioactive wastes and thermonuclear war--be avoided by technical fixes, institutional responses, religion, or by doing nothing? These are the questions addressed in this paper

  20. Integrated Circuits for Linear and Efficient Receivers

    OpenAIRE

    Östman, Kim

    2014-01-01

    This dissertation presents original research contributions in the form of five integrated circuit (IC) implementations and seven scientific publications. They present advances related to high-Q resonators, DC-DC converters, and programmable RF front-ends for integrated wireless receivers. Because these three building blocks have traditionally required implementations that are partly external to the IC, the ultimate target is to reduce system size, cost, and complexity. Wireless receivers u...

  1. Energy Harvesting Using an Analog Circuit under Multimodal Vibration

    OpenAIRE

    Shigeru Shimose; Kanjuro Makihara; Junjiro Onoda

    2013-01-01

    The efficiency of harvesting energy from a vibrating structure using a piezoelectric transducer and a simple analog circuit is investigated experimentally. This analog circuit was originally invented for a synchronized switch damping on inductor (SSDI) technique, which enhances the damping of mechanical vibration. In this study, the circuit is used to implement a synchronized switch harvesting on inductor (SSHI) technique. A multiple degree of freedom (MDOF) structure is excited by single sin...

  2. Terahertz backward wave oscillator circuits

    Science.gov (United States)

    Oviedo Vela, Guillermo Antonio

    This work focuses on increasing the electric field mode-electron beam interaction in terahertz backward-wave oscillators through increasing the interaction impedance of the slow wave circuit. In a backward wave oscillator (BWO) or a traveling wave tube (TWT), the electric field traveling in the waveguide interacts with an electron beam grazing or piercing the electric field of a slow wave circuit and transfers energy from the beam to the circuit mode. The mechanism of this interaction is analyzed and the traditional model is adapted to provide one that is scalable to terahertz frequencies. The efficiency of the BWO can be enhanced by improving the interaction between the beam and the circuit modes, utilizing beam sources with greater current densities and using larger magnetic fields. This work presents the results on the modeling, fabrication and performance of the mode-piercing and mode-grazing slow wave circuits studied. Meandering folded waveguides and interdigital lines were modeled to evaluate their interaction impedance and electron beam requirements at terahertz frequencies. The models were verified against published results. Because of their low interaction impedance, terahertz meandering waveguides would need to be excited with large current density electron beams which in turn would require large magnets for their control. Interdigital lines were found to be the slow-wave circuit of choice in this work because their high interaction impedance and their ability to operate with low voltage, and low current density electron beams. Finite element numerical calculations were used to design, optimize and scale a terahertz free interdigital line (FIDL) circuit. The designed free interdigital line was fabricated using microfabrication technologies. Characterization of a free interdigital line (FIDL) circuit was performed in a tube body with a dispenser cathode and a three-anode Pierce gun. The FIDL measured output was compared with the calculated result and its

  3. Approximate circuits for increased reliability

    Energy Technology Data Exchange (ETDEWEB)

    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 reference 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.

  4. Approximate circuits for increased reliability

    Energy Technology Data Exchange (ETDEWEB)

    Hamlet, Jason R.; Mayo, Jackson R.

    2015-12-22

    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 reference 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.

  5. Circuit analysis with Multisim

    CERN Document Server

    Baez-Lopez, David

    2011-01-01

    This book is concerned with circuit simulation using National Instruments Multisim. It focuses on the use and comprehension of the working techniques for electrical and electronic circuit simulation. The first chapters are devoted to basic circuit analysis.It starts by describing in detail how to perform a DC analysis using only resistors and independent and controlled sources. Then, it introduces capacitors and inductors to make a transient analysis. In the case of transient analysis, it is possible to have an initial condition either in the capacitor voltage or in the inductor current, or bo

  6. Troubleshooting analog circuits

    CERN Document Server

    Pease, Robert A

    1991-01-01

    Troubleshooting Analog Circuits is a guidebook for solving product or process related problems in analog circuits. The book also provides advice in selecting equipment, preventing problems, and general tips. The coverage of the book includes the philosophy of troubleshooting; the modes of failure of various components; and preventive measures. The text also deals with the active components of analog circuits, including diodes and rectifiers, optically coupled devices, solar cells, and batteries. The book will be of great use to both students and practitioners of electronics engineering. Other

  7. Plasmonic Nanoguides and Circuits

    CERN Document Server

    Bozhevolnyi, Sergey

    2008-01-01

    Modern communication systems dealing with huge amounts of data at ever increasing speed try to utilize the best aspects of electronic and optical circuits. Electronic circuits are tiny but their operation speed is limited, whereas optical circuits are extremely fast but their sizes are limited by diffraction. Waveguide components utilizing surface plasmon (SP) modes were found to combine the huge optical bandwidth and compactness of electronics, and plasmonics thereby began to be considered as the next chip-scale technology. In this book, the authors concentrate on the SP waveguide configurati

  8. Nonlinear dynamics in circuits

    CERN Document Server

    Carroll, TL

    1995-01-01

    This volume describes the use of simple analog circuits to study nonlinear dynamics, chaos and stochastic resonance. The circuit experiments that are described are mostly easy and inexpensive to reproduce, and yet these experiments come from the forefront of nonlinear dynamics research. The individual chapters describe why analog circuits are so useful for studying nonlinear dynamics, and include theoretical as well as experimental results from some of the leading researchers in the field. Most of the articles contain some tutorial sections for the less experienced readers.The audience for thi

  9. Counting rate logarithmic circuits

    International Nuclear Information System (INIS)

    This paper describes the basic circuit and the design method for a multidecade logarithmic counting ratemeter. The method is based on the charging and discharging of several RC time constants. An F.E.T. switch is used and the drain current is converted into a proportional voltage by a current to voltage converter. The logarithmic linearity was estimated for 4 decades starting from 50 cps. This circuit can be used in several nuclear instruments like survey meters and counting systems. This circuits has been developed as part of campbell channel instrumentation. (author)

  10. Optoelectronics circuits manual

    CERN Document Server

    Marston, R M

    2013-01-01

    Optoelectronics Circuits Manual covers the basic principles and characteristics of the best known types of optoelectronic devices, as well as the practical applications of many of these optoelectronic devices. The book describes LED display circuits and LED dot- and bar-graph circuits and discusses the applications of seven-segment displays, light-sensitive devices, optocouplers, and a variety of brightness control techniques. The text also tackles infrared light-beam alarms and multichannel remote control systems. The book provides practical user information and circuitry and illustrations.

  11. Modern TTL circuits manual

    CERN Document Server

    Marston, R M

    2013-01-01

    Modern TTL Circuits Manual provides an introduction to the basic principles of Transistor-Transistor Logic (TTL). This book outlines the major features of the 74 series of integrated circuits (ICs) and introduces the various sub-groups of the TTL family.Organized into seven chapters, this book begins with an overview of the basics of digital ICs. This text then examines the symbology and mathematics of digital logic. Other chapters consider a variety of topics, including waveform generator circuitry, clocked flip-flop and counter circuits, special counter/dividers, registers, data latches, com

  12. Printed circuit for ATLAS

    CERN Multimedia

    Laurent Guiraud

    1999-01-01

    A printed circuit board made by scientists in the ATLAS collaboration for the transition radiaton tracker (TRT). This will read data produced when a high energy particle crosses the boundary between two materials with different electrical properties.

  13. High temperature circuit breaker

    Science.gov (United States)

    Edwards, R. N.; Travis, E. F.

    1970-01-01

    Alternating current circuit breaker is suitable for reliable long-term service at 1000 deg F in the vacuum conditions of outer space. Construction materials are resistant to nuclear radiation and vacuum welding. Service test conditions and results are given.

  14. Latching overcurrent circuit breaker

    Science.gov (United States)

    Moore, M. L.

    1970-01-01

    Circuit breaker consists of a preset current amplitude sensor, and a lamp-photo-resistor combination in a feedback arrangement which energizes a power switching relay. The ac input power is removed from the load at predetermined current amplitudes.

  15. Synthetic in vitro circuits

    OpenAIRE

    Hockenberry, Adam J.; Jewett, Michael C.

    2012-01-01

    Inspired by advances in the ability to construct programmable circuits in living organisms, in vitro circuits are emerging as a viable platform for designing, understanding, and exploiting dynamic biochemical circuitry. In vitro systems allow researchers to directly access and manipulate biomolecular parts without the unwieldy complexity and intertwined dependencies that often exist in vivo. Experimental and computational foundations in DNA, DNA/RNA, and DNA/RNA/protein based circuitry have g...

  16. Overriding Faulty Circuit Breakers

    Science.gov (United States)

    Robbins, Richard L.; Pierson, Thomas E.

    1987-01-01

    Retainer keeps power on in emergency. Simple mechanical device attaches to failed aircraft-type push/pull circuit breaker to restore electrical power temporarily until breaker replaced. Device holds push/pull button in closed position; unnecessary for crewmember to hold button in position by continual finger pressure. Sleeve and plug hold button in, overriding mechanical failure in circuit breaker. Windows in sleeve show button position.

  17. Delay test generation for synchronous sequential circuits

    Science.gov (United States)

    Devadas, Srinivas

    1989-05-01

    We address the problem of generating tests for delay faults in non-scan synchronous sequential circuits. Delay test generation for sequential circuits is a considerably more difficult problem than delay testing of combinational circuits and has received much less attention. In this paper, we present a method for generating test sequences to detect delay faults in sequential circuits using the stuck-at fault sequential test generator STALLION. The method is complete in that it will generate a delay test sequence for a targeted fault given sufficient CPU time, if such a sequence exists. We term faults for which no delay test sequence exists, under out test methodology, sequentially delay redundant. We describe means of eliminating sequential delay redundancies in logic circuits. We present a partial-scan methodology for enhancing the testability of difficult-to-test of untestable sequential circuits, wherein a small number of flip-flops are selected and made controllable/observable. The selection process guarantees the elimination of all sequential delay redundancies. We show that an intimate relationship exists between state assignment and delay testability of a sequential machine. We describe a state assignment algorithm for the synthesis of sequential machines with maximal delay fault testability. Preliminary experimental results using the test generation, partial-scan and synthesis algorithm are presented.

  18. Fractal Electronic Circuits Assembled From Nanoclusters

    Science.gov (United States)

    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.

  19. Peak reading detector circuit

    International Nuclear Information System (INIS)

    The peak reading detector circuit serves for picking up the instants during which peaks of a given polarity occur in sequences of signals in which the extreme values, their time intervals, and the curve shape of the signals vary. The signal sequences appear in measuring the foetal heart beat frequence from amplitude-modulated ultrasonic, electrocardiagram, and blood pressure signals. In order to prevent undesired emission of output signals from, e. g., disturbing intermediate extreme values, the circuit consists of the series connections of a circuit to simulate an ideal diode, a strong unit, a discriminator for the direction of charging current, a time-delay circuit, and an electronic switch lying in the decharging circuit of the storage unit. The time-delay circuit thereby causes storing of a preliminary maximum value being used only after a certain time delay for the emission of the output signal. If a larger extreme value occurs during the delay time the preliminary maximum value is cleared and the delay time starts running anew. (DG/PB)

  20. The Communication in Science Inquiry Project (CISIP): A Project to Enhance Scientific Literacy through the Creation of Science Classroom Discourse Communities

    Science.gov (United States)

    Baker, Dale R.; Lewis, Elizabeth B.; Purzer, Senay; Watts, Nievita Bueno; Perkins, Gita; Uysal, Sibel; Wong, Sissy; Beard, Rachelle; Lang, Michael

    2009-01-01

    This study reports on the context and impact of the Communication in Science Inquiry Project (CISIP) professional development to promote teachers' and students' scientific literacy through the creation of science classroom discourse communities. The theoretical underpinnings of the professional development model are presented and key professional…

  1. An Inquiry-Based Practical for a Large, Foundation-Level Undergraduate Laboratory that Enhances Student Understanding of Basic Cellular Concepts and Scientific Experimental Design

    Science.gov (United States)

    Bugarcic, A.; Zimbardi, K.; Macaranas, J.; Thorn, P.

    2012-01-01

    Student-centered education involving research experiences or inquiry have been shown to help undergraduate students understand, and become excited about, the process of scientific investigation. These benefits are particularly important for students in the early stages of their degree (Report and Kenny,…

  2. Should scientific realists be platonists?

    DEFF Research Database (Denmark)

    Busch, Jacob; Morrison, Joe

    2015-01-01

    Realists about are arrived at by any inferen- tial route which eschews causes (§3), and nor is there any direct pressure for Scientific Real- ists to change their inferential methods (§4). We suggest that in order to maintain inferential parity with Scientific Realism, proponents of EIA need to give......Enhanced Indispensability Arguments (EIA) claim that Scientific Realists are committed to the existence of mathematical entities due to their reliance on Inference to the Best Explana- tion (IBE). Our central question concerns this purported parity of reasoning: do people who defend the EIA make an...... appropriate use of the resources of Scientific Realism (in particular, IBE) to achieve platonism? (§2) We argue that just because a variety of different inferential strategies can be employed by Scientific Realists does not mean that ontological conclusions concerning which things we should be Scientific...

  3. VLSI circuit simulation using a vector computer

    Science.gov (United States)

    Mcgrogan, S. K.

    1984-01-01

    Simulation of circuits having more than 2000 active devices requires the largest, fastest computers available. A vector computer, such as the CYBER 205, can yield great speed and cost advantages if efforts are made to adapt the simulation program to the strengths of the computer. ASPEC and SPICE (1), two widely used circuit simulation programs, are discussed. ASPECV and VAMOS (5) are respectively vector adaptations of these two simulators. They demonstrate the substantial performance enhancements possible for this class of algorithm on the CYBER 205.

  4. Energy Harvesting Using an Analog Circuit under Multimodal Vibration

    Directory of Open Access Journals (Sweden)

    Shigeru Shimose

    2013-01-01

    Full Text Available The efficiency of harvesting energy from a vibrating structure using a piezoelectric transducer and a simple analog circuit is investigated experimentally. This analog circuit was originally invented for a synchronized switch damping on inductor (SSDI technique, which enhances the damping of mechanical vibration. In this study, the circuit is used to implement a synchronized switch harvesting on inductor (SSHI technique. A multiple degree of freedom (MDOF structure is excited by single sinusoidal forces at its resonant frequencies and by random forces. The piezoelectric transducer converts this mechanical energy into electrical energy which is harvested using a standard rectifier bridge circuit with and without our analog circuit. Experimental results show that our analog circuit makes it possible to harvest twice as much energy under both single sinusoidal and random vibration excitations.

  5. The Mind Grows Circuits

    CERN Document Server

    Panigrahy, Rina

    2012-01-01

    There is a vast supply of prior art that study models for mental processes. Some studies in psychology and philosophy approach it from an inner perspective in terms of experiences and percepts. Others such as neurobiology or connectionist-machines approach it externally by viewing the mind as complex circuit of neurons where each neuron is a primitive binary circuit. In this paper, we also model the mind as a place where a circuit grows, starting as a collection of primitive components at birth and then builds up incrementally in a bottom up fashion. A new node is formed by a simple composition of prior nodes when we undergo a repeated experience that can be described by that composition. Unlike neural networks, however, these circuits take "concepts" or "percepts" as inputs and outputs. Thus the growing circuits can be likened to a growing collection of lambda expressions that are built on top of one another in an attempt to compress the sensory input as a heuristic to bound its Kolmogorov Complexity.

  6. Scientific Fraud

    OpenAIRE

    Balk-Møller, Carl August; Mogensen, Sofia Lin; RAATRÆ LUNDSTEIN, SARAH; Haubroe Larsen, André; Lohse, Mayasarah; Reininger Ardilsø, Lisa; Henrysdóttir, Gu∂run; Sondergaard, Nikolai

    2014-01-01

    This study examines the developments of SSRIs and the presence of them in the market. Dr. Peter Gøtszche’s book “Deadly Medicines and Organized Crime”, claims that scientific fraud is a big part of the pharmaceutical industry and the whole healthcare system in general. Through analyzing Peter Gøtszche’s book and several of his sources, the study aims to create a roadmap in the project, that resembles the process of the antidepressant drugs have to go through, to go from an idea to a patient. ...

  7. Lighting the Way through Scientific Discourse

    Science.gov (United States)

    Yang, Li-hsuan

    2008-01-01

    This article describes a thought-provoking lesson that compares various arrangements of lamp-battery circuits to help students develop the motivation and competence to participate in scientific discourse for knowledge construction. Through experimentation and discourse, students explore concepts about voltage, current, resistance, and Ohm's law.…

  8. Scientific Growth

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    As one of the world's largest grain consumers,food security has always been a major concern for the Chinese nation.China must confront the challenge of feeding a fifth of the world's population with less than 9 percent of the planet's arable land.In 2011,China's grain output recorded growth for the eighth successive year,and total production reached an all-time high of 571million tons.In terms of food security,China's goal is to maintain a self-sufficiency rate of above 95 percent.However,an annual net population growth of 7.39 million and the effective decline of the area of farmland in the country,as a result of urbanization,make achieving such selfsufficiency a serious challenge.Given the heavy burden placed on Chinese agriculture,constantly raising productivity by relying on scientific and technological progress has become a priority for China's agricultural sector.The Ministry of Agriculture,for example,has worked to raise China's annual grain yield per-unit area by 1 percent,on average,over the past decade.Last year,the contributory rate of scientific and technological development to China's agriculture reached 52 percent,surpassing the contribution made by land,labor and other production factors for the first time in history.

  9. How music training enhances working memory: a cerebrocerebellar blending mechanism that can lead equally to scientific discovery and therapeutic efficacy in neurological disorders

    OpenAIRE

    Vandervert, Larry

    2015-01-01

    Background Following in the vein of studies that concluded that music training resulted in plastic changes in Einstein’s cerebral cortex, controlled research has shown that music training (1) enhances central executive attentional processes in working memory, and (2) has also been shown to be of significant therapeutic value in neurological disorders. Within this framework of music training-induced enhancement of central executive attentional processes, the purpose of this article is to argue...

  10. Circuit electromechanics with single photon strong coupling

    International Nuclear Information System (INIS)

    In circuit electromechanics, the coupling strength is usually very small. Here, replacing the capacitor in circuit electromechanics by a superconducting flux qubit, we show that the coupling among the qubit and the two resonators can induce effective electromechanical coupling which can attain the strong coupling regime at the single photon level with feasible experimental parameters. We use dispersive couplings among two resonators and the qubit while the qubit is also driven by an external classical field. These couplings form a three-wave mixing configuration among the three elements where the qubit degree of freedom can be adiabatically eliminated, and thus results in the enhanced coupling between the two resonators. Therefore, our work constitutes the first step towards studying quantum nonlinear effect in circuit electromechanics

  11. Circuit electromechanics with single photon strong coupling

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Zheng-Yuan, E-mail: zyxue@scnu.edu.cn; Yang, Li-Na [Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, and School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006 (China); Zhou, Jian, E-mail: jianzhou8627@163.com [Department of Electronic Communication Engineering, Anhui Xinhua University, Hefei 230088 (China); Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, and School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006 (China)

    2015-07-13

    In circuit electromechanics, the coupling strength is usually very small. Here, replacing the capacitor in circuit electromechanics by a superconducting flux qubit, we show that the coupling among the qubit and the two resonators can induce effective electromechanical coupling which can attain the strong coupling regime at the single photon level with feasible experimental parameters. We use dispersive couplings among two resonators and the qubit while the qubit is also driven by an external classical field. These couplings form a three-wave mixing configuration among the three elements where the qubit degree of freedom can be adiabatically eliminated, and thus results in the enhanced coupling between the two resonators. Therefore, our work constitutes the first step towards studying quantum nonlinear effect in circuit electromechanics.

  12. Semiconductor circuits worked examples

    CERN Document Server

    Abrahams, J R; Hiller, N

    1966-01-01

    Semiconductor Circuits: Worked Examples is a companion volume to Semiconductor Circuits: Theory, Design and Experiment. This book is a presentation of many questions at the undergraduate and technical level centering on the transistor. The problems concern basic physical theories of energy bands, covalent bond, and crystal lattice. Questions regarding the intrinsic property and impurity of semiconductors are also asked after the book presents a brief discussion of semiconductors. This book addresses the physical principles of semiconductor devices by presenting questions and worked examples o

  13. Circuit Quantum Electrodynamics

    CERN Document Server

    Bishop, Lev S

    2010-01-01

    Circuit Quantum Electrodynamics (cQED), the study of the interaction between superconducting circuits behaving as artificial atoms and 1-dimensional transmission-line resonators, has shown much promise for quantum information processing tasks. For the purposes of quantum computing it is usual to approximate the artificial atoms as 2-level qubits, and much effort has been expended on attempts to isolate these qubits from the environment and to invent ever more sophisticated control and measurement schemes. Rather than focussing on these technological aspects of the field, this thesis investigates the opportunities for using these carefully engineered systems for answering questions of fundamental physics.

  14. Primer printed circuit boards

    CERN Document Server

    Argyle, Andrew

    2009-01-01

    Step-by-step instructions for making your own PCBs at home. Making your own printed circuit board (PCB) might seem a daunting task, but once you master the steps, it's easy to attain professional-looking results. Printed circuit boards, which connect chips and other components, are what make almost all modern electronic devices possible. PCBs are made from sheets of fiberglass clad with copper, usually in multiplelayers. Cut a computer motherboard in two, for instance, and you'll often see five or more differently patterned layers. Making boards at home is relatively easy

  15. Compound semiconductor integrated circuits

    CERN Document Server

    Vu, Tho T

    2003-01-01

    This is the book version of a special issue of the International Journal of High Speed Electronics and Systems , reviewing recent work in the field of compound semiconductor integrated circuits. There are fourteen invited papers covering a wide range of applications, frequencies and materials. These papers deal with digital, analog, microwave and millimeter-wave technologies, devices and integrated circuits for wireline fiber-optic lightwave transmissions, and wireless radio-frequency microwave and millimeter-wave communications. In each case, the market is young and experiencing rapid growth

  16. Electronic circuits fundamentals & applications

    CERN Document Server

    Tooley, Mike

    2015-01-01

    Electronics explained in one volume, using both theoretical and practical applications.New chapter on Raspberry PiCompanion website contains free electronic tools to aid learning for students and a question bank for lecturersPractical investigations and questions within each chapter help reinforce learning Mike Tooley provides all the information required to get to grips with the fundamentals of electronics, detailing the underpinning knowledge necessary to appreciate the operation of a wide range of electronic circuits, including amplifiers, logic circuits, power supplies and oscillators. The

  17. Electronic circuit analysis

    CERN Document Server

    Kishore, K Lal

    2008-01-01

    Second Edition of the book Electronic Circuit Analysis is brought out with certain new Topics and reorganization of text matter into eight units. With addition of new topics, syllabi of many universities in this subject can be covered. Besides this, the book can also meet the requirements of M.Sc (Electronics), AMIETE, AMIE (Electronics) courses. Text matter is improved thoroughly. New topics like frequency effects in multistage amplifiers, amplifier circuit analysis, design of high frequency amplifiers, switching regulators, voltage multipliers, Uninterrupted Power Supplies (UPS), and Switchi

  18. Chaotic memristive circuit: equivalent circuit realization and dynamical analysis

    Institute of Scientific and Technical Information of China (English)

    Bao Bo-Cheng; Xu Jian-Ping; Zhou Guo-Hua; Ma Zheng-Hua; Zou Ling

    2011-01-01

    In this paper,a practical equivalent circuit of an active flux-controlled memristor characterized by smooth piecewise-quadratic nonlinearity is designed and an experimental chaotic memristive circuit is implemented.The chaotic memristive circuit has an equilibrium set and its stability is dependent on the initial state of the memristor.The initial state-dependent and the circuit parameter-dependent dynamics of the chaotic memristive circuit are investigated via phase portraits,bifurcation diagrams and Lyapunov exponents.Both experimental and simulation results validate the proposed equivalent circuit realization of the active flux-controlled memristor.

  19. ESD analog circuits and design

    CERN Document Server

    Voldman, Steven H

    2014-01-01

    A comprehensive and in-depth review of analog circuit layout, schematic architecture, device, power network and ESD design This book will provide a balanced overview of analog circuit design layout, analog circuit schematic development, architecture of chips, and ESD design.  It will start at an introductory level and will bring the reader right up to the state-of-the-art. Two critical design aspects for analog and power integrated circuits are combined. The first design aspect covers analog circuit design techniques to achieve the desired circuit performance. The second and main aspect pres

  20. Circuit Theory for SPICE of Spintronic Integrated Circuits

    OpenAIRE

    Manipatruni, Sasikanth; Nikonov, Dmitri E.; Young, Ian A.

    2011-01-01

    We present a theoretical and a numerical formalism for analysis and design of spintronic integrated circuits (SPINICs). The formalism encompasses a generalized circuit theory for spintronic integrated circuits based on nanomagnetic dynamics and spin transport. We propose an extension to the Modified Nodal Analysis technique for the analysis of spin circuits based on the recently developed spin conduction matrices. We demonstrate the applicability of the framework using an example spin logic c...

  1. Addiction: Decreased reward sensitivity and increased expectation sensitivity conspire to overwhelm the brain's control circuit

    OpenAIRE

    Volkow, Nora D.; Wang, Gene-Jack; Fowler, Joanna S.; Tomasi, Dardo; Telang, Frank; Baler, Ruben

    2010-01-01

    Based on brain imaging findings, we present a model according to which addiction emerges as an imbalance in the information processing and integration among various brain circuits and functions. The dysfunctions reflect (a) decreased sensitivity of reward circuits, (b) enhanced sensitivity of memory circuits to conditioned expectations to drugs and drug cues, stress reactivity, and (c) negative mood, and a weakened control circuit. Although initial experimentation with a drug of abuse is larg...

  2. Reducing energy with asynchronous circuits

    OpenAIRE

    Rivas Barragan, Daniel

    2012-01-01

    Reducing energy consumption using asynchronous circuits. The elastic clocks approach has been implemented along with a closed-feedback loop in order to achieve a lower energy consumption along with more reliability in integrated circuits.

  3. ABOUT TRACK CIRCUIT CALCULATION METHOD DEPENDENT ON FERROMAGNET PROPERTIES IN CONDITIONS OF TRACTION CURRENT NOISE INFLUENCE

    OpenAIRE

    ZHURAVLEV A. YU.

    2016-01-01

    Purpose. The work is intended to investigate the electromagnetic processes in impedance bond in order to improve noise immunity of track circuits (TC) for safe railway operation. Methodology. To achieve this purpose the methods of scientific analysis, mathematical modelling, experimental study, a large-scale simulation were used. Findings. The work examined the interference affecting the normal performance of track circuits. To a large extent, part of track circuit damages account for failure...

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

    Science.gov (United States)

    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.

  5. Unstable oscillators based hyperchaotic circuit

    DEFF Research Database (Denmark)

    Murali, K.; Tamasevicius, A.; G. Mykolaitis, A.;

    1999-01-01

    A simple 4th order hyperchaotic circuit with unstable oscillators is described. The circuit contains two negative impedance converters, two inductors, two capacitors, a linear resistor and a diode. The Lyapunov exponents are presented to confirm hyperchaotic nature of the oscillations in the...... circuit. The performance of the circuit is investigated by means of numerical integration of appropriate differential equations, PSPICE simulations, and hardware experiment....

  6. The LMT circuit and SPICE

    DEFF Research Database (Denmark)

    Lindberg, Erik; Murali, K.; Tamacevicius, Arunas

    2006-01-01

    The state equations of the LMT circuit are modeled as a dedicated analogue computer circuit and solved by means of PSpice. The nonlinear part of the system is studied. Problems with the PSpice program are presented.......The state equations of the LMT circuit are modeled as a dedicated analogue computer circuit and solved by means of PSpice. The nonlinear part of the system is studied. Problems with the PSpice program are presented....

  7. Value Constraint and Monotone circuit

    OpenAIRE

    Kobayashi, Koji

    2012-01-01

    This paper talks about that monotone circuit is P-Complete. Decision problem that include P-Complete is mapping that classify input with a similar property. Therefore equivalence relation of input value is important for computation. But monotone circuit cannot compute the equivalence relation of the value because monotone circuit can compute only monotone function. Therefore, I make the value constraint explicitly in the input and monotone circuit can compute equivalence relation. As a result...

  8. Neurotrophins and spinal circuit function

    OpenAIRE

    Lorne M. Mendell

    2014-01-01

    Work early in the last century emphasized the stereotyped activity of spinal circuits based on studies of reflexes. However, the last several decades have focused on the plasticity of these spinal circuits. These considerations began with studies of the effects of monoamines on descending and reflex circuits. In recent years new classes of compounds called growth factors that are found in peripheral nerves and the spinal cord have been shown to affect circuit behavior in the spinal cord. In t...

  9. Dynamical models of cortical circuits.

    OpenAIRE

    Wolf, Fred; Engelken, Rainer; Puelma-Touzel, Maximilian; Weidinger, Juan Daniel Flórez; Neef, Andreas

    2014-01-01

    Cortical neurons operate within recurrent neuronal circuits. Dissecting their operation is key to understanding information processing in the cortex and requires transparent and adequate dynamical models of circuit function. Convergent evidence from experimental and theoretical studies indicates that strong feedback inhibition shapes the operating regime of cortical circuits. For circuits operating in inhibition-dominated regimes, mathematical and computational studies over the past several y...

  10. Diode, transistor & fet circuits manual

    CERN Document Server

    Marston, R M

    2013-01-01

    Diode, Transistor and FET Circuits Manual is a handbook of circuits based on discrete semiconductor components such as diodes, transistors, and FETS. The book also includes diagrams and practical circuits. The book describes basic and special diode characteristics, heat wave-rectifier circuits, transformers, filter capacitors, and rectifier ratings. The text also presents practical applications of associated devices, for example, zeners, varicaps, photodiodes, or LEDs, as well as it describes bipolar transistor characteristics. The transistor can be used in three basic amplifier configuration

  11. Static Switching Dynamic Buffer Circuit

    OpenAIRE

    Pandey, A. K.; R. A. Mishra; R. K. Nagaria

    2013-01-01

    We proposed footless domino logic buffer circuit. It minimizes redundant switching at the dynamic and the output nodes. The proposed circuit avoids propagation of precharge pulse to the output node and allows the dynamic node which saves power consumption. Simulation is done using 0.18 µm CMOS technology. We have calculated the power consumption, delay, and power delay product of the proposed circuit and compared the results with the existing circuits for different logic function, loading co...

  12. Soft errors from particles to circuits

    CERN Document Server

    Autran, Jean-Luc

    2015-01-01

    ""Soft Errors: From Particles to Circuits covers all aspects of the design, use, application, performance, and testing of parts, devices, and systems and addresses every perspective from an engineering, scientific, or physical point of view. … Many good texts have been written on similar subjects, but none as thorough, as clear, and as complete as this volume. … [The authors] have mastered the past, absorbed the present, and captured the trends of the future in one of the most important technologies of our time. … An extremely useful text that has succeeded in presenting wit

  13. Designer's handbook of instrumentation and control circuits

    CERN Document Server

    Carr, Joseph J

    1991-01-01

    Here is a comprehensive, practical guide to the entire process of analog instrumentation and control, from sensor input to data conversion circuitry and final output. This readable handbook avoids complex mathematical treatments, instead taking an applications-oriented approach and presenting many sample circuits and concrete examples. It is an essential reference for engineers and high-level technicians in a variety of scientific and engineering fields--anywhere data is collected electronically and where such data is used to control physical processes.Key Features* Covers design o

  14. Neuromorphic silicon neuron circuits

    Directory of Open Access Journals (Sweden)

    GiacomoIndiveri

    2011-05-01

    Full Text Available Hardware implementations of spiking neurons can be extremely useful for a large variety of applications, ranging from high-speed modeling of large-scale neural systems to real-time behaving systems, to bidirectional brain-machine interfaces. The specific circuit solutions used to implement silicon neurons depend on the application requirements. In this paper we describe the most common building blocks and techniques used to implement these circuits, and present an overview of a wide range of neuromorphic silicon neurons, which implement different computational models, ranging from biophysically realistic and conductance based Hodgkin-Huxley models to bi-dimensional generalized adaptive Integrate and Fire models. We compare the different design methodologies used for each silicon neuron design described, and demonstrate their features with experimental results, measured from a wide range of fabricated VLSI chips.

  15. LC-Circuit Calorimetry

    CERN Document Server

    Bossen, Olaf

    2011-01-01

    We present a new type of calorimeter in which we couple an unknown heat capacity with the aid of Peltier elements to an electrical circuit. The use of an electrical inductance and an amplifier in the circuit allows us to achieve autonomous oscillations, and the measurement of the corresponding resonance frequency makes it possible to accurately measure the heat capacity with an intrinsic statistical error that decreases as ~t^{-3/2} with measuring time t, as opposed to a corresponding error ~t^{-1/2} in the conventional alternating current (a.c.) method to measure heat capacities. We have built a demonstration experiment to show the feasibility of the new technique, and we have tested it on a gadolinium sample at its transition to the ferromagnetic state.

  16. Teachers' conceptions of the nature of science: Analyzing the impact of a teacher enhancement program in changing attitudes and perceptions of science and scientific research

    Science.gov (United States)

    Govett, Aimee Lee

    The purpose of this study was to determine the efficacy of a residential science research experience in changing participants' attitudes and understanding of the nature of science and their view of themselves as science researchers. Data from interviews, journal writings, classroom observations and two pre-post instruments were used in the evaluation plan. As participants of this study, 16 inservice teachers (K--16) attended a two-week residential institute at the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virginia. The format of the institute featured a scientific research experience designed to arm its participants with the skills needed to model their classroom teaching after scientific research. The program included lessons on the fundamentals of radio astronomy, science talks and interactions with practicing scientists, in-depth tours of the NRAO facilities, and pedagogical instruction for implementing research in the classroom. The WVU College of Education staff and the NRAO staff stressed the importance of the nature of the research experience offered to these teachers. In the Education Sessions the WVU science education staff guided participants through the steps required to turn their experience around, in order to develop student research projects for their classrooms. The results from the Research Self Assessment instrument show significant gains for all participants in being more comfortable doing research. For the Nature of Science and Science Teaching instrument there were only three items that showed significant gains for all participants both in understanding the nature of science and in their views on implementing the Green Bank constructivist learning philosophy. The women, especially the elementary teacher group, showed the greatest change in their understanding of the nature of science as reflected in the interviews as well as in their personal journals. The seven men, who were all in the secondary field, made no significant

  17. Functional molecules in electronic circuits.

    Science.gov (United States)

    Weibel, Nicolas; Grunder, Sergio; Mayor, Marcel

    2007-08-01

    Molecular electronics is a fascinating field of research contributing to both fundamental science and future technological achievements. A promising starting point for molecular devices is to mimic existing electronic functions to investigate the potential of molecules to enrich and complement existing electronic strategies. Molecules designed and synthesized to be integrated into electronic circuits and to perform an electronic function are presented in this article. The focus is set in particular on rectification and switching based on molecular devices, since the control over these two parameters enables the assembly of memory units, likely the most interesting and economic application of molecular based electronics. Both historical and contemporary solutions to molecular rectification are discussed, although not exhaustively. Several examples of integrated molecular switches that respond to light are presented. Molecular switches responding to an electrochemical signal are also discussed. Finally, supramolecular and molecular systems with intuitive application potential as memory units due to their hysteretic switching are highlighted. Although a particularly attractive feature of molecular electronics is its close cooperation with neighbouring disciplines, this article is written from the point of view of a chemist. Although the focus here is largely on molecular considerations, innovative contributions from physics, electro engineering, nanotechnology and other scientific disciplines are equally important. However, the ability of the chemist to correlate function with structure, to design and to provide tailor-made functional molecules is central to molecular electronics. PMID:17637951

  18. Promoting Scientific Spirit to Cultivate Scientific Culture

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Scientific culture is an advanced culture that is based on scientific knowledge and supported by the scientific method, with scientific thinking as its core and scientific spirit as its soul. During the process of modernization, it has profound impacts on human society in terms of values, ethics, mode of thinking, lifestyle and code of conduct, offering human civilization an important ideological source, physical foundation, technological tool and effective carrier.

  19. Refractory Neuron Circuits

    OpenAIRE

    Sarpeshkar, Rahul; Watts, Lloyd; Mead, Carver

    1992-01-01

    Neural networks typically use an abstraction of the behaviour of a biological neuron, in which the continuously varying mean firing rate of the neuron is presumed to carry information about the neuron's time-varying state of excitation. However, the detailed timing of action potentials is known to be important in many biological systems. To build electronic models of such systems, one must have well-characterized neuron circuits that capture the essential behaviour of real neur...

  20. Electronic devices and circuits

    CERN Document Server

    Kishore, K Lal

    2008-01-01

    This book is written in a simple lucid Language along with derivation of equations and supported by numerous solved problems to help the student to understand the concepts clearly.Advances in Miniaturization of Electronic Systems by ever increasing packaging densities on Integrated Circuits has made it very essential for thorough Knowledge of the concepts, phenomenon, characteristics and behaviour of semiconductor Devices for students and professionals.

  1. PARTICLE BEAM TRACKING CIRCUIT

    Science.gov (United States)

    Anderson, O.A.

    1959-05-01

    >A particle-beam tracking and correcting circuit is described. Beam induction electrodes are placed on either side of the beam, and potentials induced by the beam are compared in a voltage comparator or discriminator. This comparison produces an error signal which modifies the fm curve at the voltage applied to the drift tube, thereby returning the orbit to the preferred position. The arrangement serves also to synchronize accelerating frequency and magnetic field growth. (T.R.H.)

  2. Engineering prokaryotic gene circuits

    OpenAIRE

    Michalodimitrakis, Konstantinos; Isalan, Mark

    2009-01-01

    Engineering of synthetic gene circuits is a rapidly growing discipline, currently dominated by prokaryotic transcription networks, which can be easily rearranged or rewired to give different output behaviours. In this review, we examine both a rational and a combinatorial design of such networks and discuss progress on using in vitro evolution techniques to obtain functional systems. Moving beyond pure transcription networks, more and more networks are being implemented at the level of RNA, t...

  3. Integrated Circuit Immunity

    Science.gov (United States)

    Sketoe, J. G.; Clark, Anthony

    2000-01-01

    This paper presents a DOD E3 program overview on integrated circuit immunity. The topics include: 1) EMI Immunity Testing; 2) Threshold Definition; 3) Bias Tee Function; 4) Bias Tee Calibration Set-Up; 5) EDM Test Figure; 6) EMI Immunity Levels; 7) NAND vs. and Gate Immunity; 8) TTL vs. LS Immunity Levels; 9) TP vs. OC Immunity Levels; 10) 7805 Volt Reg Immunity; and 11) Seventies Chip Set. This paper is presented in viewgraph form.

  4. Fundamental Atomtronic Circuit Elements

    Science.gov (United States)

    Lee, Jeffrey; McIlvain, Brian; Lobb, Christopher; Hill, Wendell T., III

    2012-06-01

    Recent experiments with neutral superfluid gases have shown that it is possible to create atomtronic circuits analogous to existing superconducting circuits. The goals of these experiments are to create complex systems such as Josephson junctions. In addition, there are theoretical models for active atomtronic components analogous to diodes, transistors and oscillators. In order for any of these devices to function, an understanding of the more fundamental atomtronic elements is needed. Here we describe the first experimental realization of these more fundamental elements. We have created an atomtronic capacitor that is discharged through a resistance and inductance. We will discuss a theoretical description of the system that allows us to determine values for the capacitance, resistance and inductance. The resistance is shown to be analogous to the Sharvin resistance, and the inductance analogous to kinetic inductance in electronics. This atomtronic circuit is implemented with a thermal sample of laser cooled rubidium atoms. The atoms are confined using what we call free-space atom chips, a novel optical dipole trap produced using a generalized phase-contrast imaging technique. We will also discuss progress toward implementing this atomtronic system in a degenerate Bose gas.

  5. Semiconductor integrated circuits

    International Nuclear Information System (INIS)

    An improved method involving ion implantation to form non-epitaxial semiconductor integrated circuits. These are made by forming a silicon substrate of one conductivity type with a recessed silicon dioxide region extending into the substrate and enclosing a portion of the silicon substrate. A beam of ions of opposite conductivity type impurity is directed at the substrate at an energy and dosage level sufficient to form a first region of opposite conductivity within the silicon dioxide region. This impurity having a concentration peak below the surface of the substrate forms a region of the one conductivity type which extends from the substrate surface into the first opposite type region to a depth between the concentration peak and the surface and forms a second region of opposite conductivity type. The method, materials and ion beam conditions are detailed. Vertical bipolar integrated circuits can be made this way when the first opposite type conductivity region will function as a collector. Also circuits with inverted bipolar devices when this first region functions as a 'buried'' emitter region. (U.K.)

  6. The economic scientific research, a production neo-factor

    OpenAIRE

    Elena Ciucur

    2007-01-01

    The scientific research represents a modern production neo-factor that implies two groups of coordinates: preparation and scientific research. The scientific research represents a complex of elements that confer a new orientation of high performance and is materialized in resources and new availabilities brought in active shape by the contribution of the creators and by the attraction in a specific way in the economic circuit. It is the creator of new ideas, lifting the performance and unders...

  7. Changes to the shuttle circuits

    CERN Multimedia

    GS Department

    2011-01-01

    To fit with passengers expectation, there will be some changes to the shuttle circuits as from Monday 10 October. See details on http://cern.ch/ShuttleService (on line on 7 October). Circuit No. 5 is cancelled as circuit No. 1 also stops at Bldg. 33. In order to guarantee shorter travel times, circuit No. 1 will circulate on Meyrin site only and circuit No. 2, with departures from Bldg. 33 and 500, on Prévessin site only. Site Services Section

  8. Experimental determination of circuit equations

    CERN Document Server

    Shulman, Jason; Widjaja, Matthew; Gunaratne, Gemunu H

    2013-01-01

    Kirchhoff's laws offer a general, straightforward approach to circuit analysis. Unfortunately, use of the laws becomes impractical for all but the simplest of circuits. This work presents a novel method of analyzing direct current resistor circuits. It is based on an approach developed to model complex networks, making it appropriate for use on large, complicated circuits. It is unique in that it is not an analytic method. It is based on experiment, yet the approach produces the same circuit equations obtained by more traditional means.

  9. Power system with an integrated lubrication circuit

    Science.gov (United States)

    Hoff, Brian D.; Akasam, Sivaprasad; Algrain, Marcelo C.; Johnson, Kris W.; Lane, William H.

    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.

  10. Integrated coherent matter wave circuits

    International Nuclear Information System (INIS)

    An integrated coherent matter wave circuit is a single device, analogous to an integrated optical circuit, in which coherent de Broglie waves are created and then launched into waveguides where they can be switched, divided, recombined, and detected as they propagate. Applications of such circuits include guided atom interferometers, atomtronic circuits, and precisely controlled delivery of atoms. We report experiments demonstrating integrated circuits for guided coherent matter waves. The circuit elements are created with the painted potential technique, a form of time-averaged optical dipole potential in which a rapidly moving, tightly focused laser beam exerts forces on atoms through their electric polarizability. Moreover, the source of coherent matter waves is a Bose-Einstein condensate (BEC). Finally, we launch BECs into painted waveguides that guide them around bends and form switches, phase coherent beamsplitters, and closed circuits. These are the basic elements that are needed to engineer arbitrarily complex matter wave circuitry

  11. Memristor based startup circuit for self biased circuits

    Science.gov (United States)

    Das, Mangal; Singh, Amit Kumar; Rathi, Amit; Singhal, Sonal

    2016-04-01

    This paper presents the design of a Memristor based startup circuit for self biased circuits. Memristor has many advantages over conventional CMOS devices such as low leakage current at nanometer scale, easy to manufacture. In this work the switching characteristics of memristor is utilized. First the theoretical equations describing the switching behavior of memristor are investigated. To prove the switching capability of Memristor, a startup circuit based on memristor is proposed which uses series combination of Memristor and capacitor. Proposed circuit is compared with the previously reported MOSFET based startup circuits. Comparison of different circuits was done to validate the results. Simulation results show that memristor based circuit can attain on (I = 12.94 µA) to off state (I = 1 .2 µA) in 25 ns while the MOSFET based startup circuits take on (I = 14.19 µA) to off state (I = 1.4 µA) in more than 90 ns. The benefit comes in terms of area because the number of components used in the circuit are lesser than the conventional startup circuits.

  12. Establishing Scientific Audit Ideas, Enhancing Executive Ability of Military Audit%树立科学审计理念 提升军队审计执行力

    Institute of Scientific and Technical Information of China (English)

    周永山; 宋奇; 于芳

    2011-01-01

    提升现代军队审计的执行力,必须牢固树立科学审计理念,准确把握军队审计的内涵和要求,强化独立、权威、服务、责任的审计意识,理顺内外机制,优化职能作用,营造良好的审计氛围,不断提升军队审计信息化水平。%To enhance the modern army audit execution, this paper puts forward to establish the concept of scientific audit, grasp the implications and requirements of military audit accurately, strengthen the auditing awareness with the characteristics of independent, authoritative, service and responsible, organize the internal and external mechanism, optimize the role of functions, create a good audit atmosphere, and upgrade the informatization level of military audit continuously.

  13. Spatiotemporal dynamics of distributed synthetic genetic circuits

    Science.gov (United States)

    Kanakov, Oleg; Laptyeva, Tetyana; Tsimring, Lev; Ivanchenko, Mikhail

    2016-04-01

    We propose and study models of two distributed synthetic gene circuits, toggle-switch and oscillator, each split between two cell strains and coupled via quorum-sensing signals. The distributed toggle switch relies on mutual repression of the two strains, and oscillator is comprised of two strains, one of which acts as an activator for another that in turn acts as a repressor. Distributed toggle switch can exhibit mobile fronts, switching the system from the weaker to the stronger spatially homogeneous state. The circuit can also act as a biosensor, with the switching front dynamics determined by the properties of an external signal. Distributed oscillator system displays another biosensor functionality: oscillations emerge once a small amount of one cell strain appears amid the other, present in abundance. Distribution of synthetic gene circuits among multiple strains allows one to reduce crosstalk among different parts of the overall system and also decrease the energetic burden of the synthetic circuit per cell, which may allow for enhanced functionality and viability of engineered cells.

  14. Novel Sleep Transistor Techniques for Low Leakage Power Peripheral Circuits

    OpenAIRE

    Rajani H.P; Srimannarayan Kulkarni

    2012-01-01

    Static power consumption is a major concern in nanometre technologies. Along with technology scaling down and higher operating speeds of CMOS VLSI circuits, the leakage power is getting enhanced. As process geometries are becoming smaller, device density increases and threshold voltage as well as oxide thickness decrease to keep pace with performance. Two novel circuit techniques for leakage current reduction in inverters with and without state retention property are presented in this work. T...

  15. Validation of symbolic expressions in circuit analysis e-learning

    OpenAIRE

    Weyten, Ludo; Rombouts, Pieter; Catteau, Benoit; De Bock, Maarten

    2011-01-01

    Symbolic circuit analysis is a cornerstone of electrical engineering education. Solving a suitable set of selected problems is essential to developing professional skills in the field. Anew method is presented for automatic validation of circuit equations representing a student's intermediate steps in the solving process. Providing this immediate feedback may strongly enhance the training effects. The new method was embedded in a Web-based e-learning system and has proved to be useful in c...

  16. Effects of grid-placed contacts on circuit performance

    OpenAIRE

    Wong, AKK; Wang, J

    2003-01-01

    The impact of grid-placed contacts on application-specific integrated circuit (ASIC) performance is studied. Although snapping contacts to grid adds restrictions during layout design, smaller circuit area can be achieved by careful selection of the grid pitch, raising the lower limit of transistor width, applying double exposure, and shrinking the minimum contact pitch enabled by more effective application of resolution enhancement technologies. The technique is demonstrated on the contact le...

  17. Electronics circuits and systems

    CERN Document Server

    Bishop, Owen

    2007-01-01

    The material in Electronics - Circuits and Systems is a truly up-to-date textbook, with coverage carefully matched to the electronics units of the 2007 BTEC National Engineering and the latest AS and A Level specifications in Electronics from AQA, OCR and WJEC. The material has been organized with a logical learning progression, making it ideal for a wide range of pre-degree courses in electronics. The approach is student-centred and includes: numerous examples and activities; web research topics; Self Test features, highlighted key facts, formulae and definitions. Each chapter ends with a set

  18. Electronic logic circuits

    CERN Document Server

    Gibson, J

    2013-01-01

    Most branches of organizing utilize digital electronic systems. This book introduces the design of such systems using basic logic elements as the components. The material is presented in a straightforward manner suitable for students of electronic engineering and computer science. The book is also of use to engineers in related disciplines who require a clear introduction to logic circuits. This third edition has been revised to encompass the most recent advances in technology as well as the latest trends in components and notation. It includes a wide coverage of application specific integrate

  19. Photonic Integrated Circuits

    Science.gov (United States)

    Merritt, Scott; Krainak, Michael

    2016-01-01

    Integrated photonics generally is the integration of multiple lithographically defined photonic and electronic components and devices (e.g. lasers, detectors, waveguides passive structures, modulators, electronic control and optical interconnects) on a single platform with nanometer-scale feature sizes. The development of photonic integrated circuits permits size, weight, power and cost reductions for spacecraft microprocessors, optical communication, processor buses, advanced data processing, and integrated optic science instrument optical systems, subsystems and components. This is particularly critical for small spacecraft platforms. We will give an overview of some NASA applications for integrated photonics.

  20. Digital logic circuit test

    International Nuclear Information System (INIS)

    This book is about digital logic circuit test, which lists the digital basic theory, basic gate like and, or And Not gate, NAND/NOR gate such as NAND gate, NOR gate, AND and OR, logic function, EX-OR gate, adder and subtractor, decoder and encoder, multiplexer, demultiplexer, flip-flop, counter such as up/down counter modulus N counter and Reset type counter, shift register, D/A and A/D converter and two supplements list of using components and TTL manual and CMOS manual.

  1. Biophotonic integrated circuits

    Science.gov (United States)

    Cohen, Daniel A.; Nolde, Jill A.; Wang, Chad S.; Skogen, Erik J.; Rivlin, A.; Coldren, Larry A.

    2004-12-01

    Biosensors rely on optical techniques to obtain high sensitivity and speed, but almost all biochips still require external light sources, optics, and detectors, which limits the widespread use of these devices. The optoelectronics technology base now allows monolithic integration of versatile optical sources, novel sensing geometries, filters, spectrometers, and detectors, enabling highly integrated chip-scale sensors. We discuss biophotonic integrated circuits built on both GaAs and InP substrates, incorporating widely tunable lasers, novel evanescent field sensing waveguides, heterodyne spectrometers, and waveguide photodetectors, suitable for high sensitivity transduction of affinity assays.

  2. Electric circuits problem solver

    CERN Document Server

    REA, Editors of

    2012-01-01

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

  3. Optoelectronics circuits manual

    CERN Document Server

    Marston, R M

    1999-01-01

    This manual is a useful single-volume guide specifically aimed at the practical design engineer, technician, and experimenter, as well as the electronics student and amateur. It deals with the subject in an easy to read, down to earth, and non-mathematical yet comprehensive manner, explaining the basic principles and characteristics of the best known devices, and presenting the reader with many practical applications and over 200 circuits. Most of the ICs and other devices used are inexpensive and readily available types, with universally recognised type numbers.The second edition

  4. Closed Circuit Videoinstallationen

    DEFF Research Database (Denmark)

    Kacunko, Slavko

    and 650 artists. This and the notes on further reading and viewing will enable deeper explorations of the material in a way not unlike the open “hyper-text”- structure. Video technique makes it possible to simultaneously record and reproduce images, sound and sequences of motion; that potential can...... and at the same time general investigations. The research project, ‘Closed-Circuit-Video Installations. A Study on the History and Theory of Media Art’, is being supported by the Fritz-Thyssen Foundation, Cologne....

  5. Electronics circuits and systems

    CERN Document Server

    Bishop, Owen

    2011-01-01

    The material in Electronics - Circuits and Systems is a truly up-to-date textbook, with coverage carefully matched to the electronics units of the 2007 BTEC National Engineering and the latest AS and A Level specifications in Electronics from AQA, OCR and WJEC. The material has been organized with a logical learning progression, making it ideal for a wide range of pre-degree courses in electronics. The approach is student-centred and includes: numerous examples and activities; web research topics; Self Test features, highlighted key facts, formulae and definitions. Ea

  6. Integrated circuit cell library

    Science.gov (United States)

    Whitaker, Sterling R. (Inventor); Miles, Lowell H. (Inventor)

    2005-01-01

    According to the invention, an ASIC cell library for use in creation of custom integrated circuits is disclosed. The ASIC cell library includes some first cells and some second cells. Each of the second cells includes two or more kernel cells. The ASIC cell library is at least 5% comprised of second cells. In various embodiments, the ASIC cell library could be 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, or 95% or more comprised of second cells.

  7. Linear integrated circuits

    CERN Document Server

    Carr, Joseph

    1996-01-01

    The linear IC market is large and growing, as is the demand for well trained technicians and engineers who understand how these devices work and how to apply them. Linear Integrated Circuits provides in-depth coverage of the devices and their operation, but not at the expense of practical applications in which linear devices figure prominently. This book is written for a wide readership from FE and first degree students, to hobbyists and professionals.Chapter 1 offers a general introduction that will provide students with the foundations of linear IC technology. From chapter 2 onwa

  8. Optically controllable molecular logic circuits

    International Nuclear Information System (INIS)

    Molecular logic circuits represent a promising technology for observation and manipulation of biological systems at the molecular level. However, the implementation of molecular logic circuits for temporal and programmable operation remains challenging. In this paper, we demonstrate an optically controllable logic circuit that uses fluorescence resonance energy transfer (FRET) for signaling. The FRET-based signaling process is modulated by both molecular and optical inputs. Based on the distance dependence of FRET, the FRET pathways required to execute molecular logic operations are formed on a DNA nanostructure as a circuit based on its molecular inputs. In addition, the FRET pathways on the DNA nanostructure are controlled optically, using photoswitching fluorescent molecules to instruct the execution of the desired operation and the related timings. The behavior of the circuit can thus be controlled using external optical signals. As an example, a molecular logic circuit capable of executing two different logic operations was studied. The circuit contains functional DNAs and a DNA scaffold to construct two FRET routes for executing Input 1 AND Input 2 and Input 1 AND NOT Input 3 operations on molecular inputs. The circuit produced the correct outputs with all possible combinations of the inputs by following the light signals. Moreover, the operation execution timings were controlled based on light irradiation and the circuit responded to time-dependent inputs. The experimental results demonstrate that the circuit changes the output for the required operations following the input of temporal light signals

  9. Optically controllable molecular logic circuits

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Takahiro, E-mail: t-nishimura@ist.osaka-u.ac.jp; Fujii, Ryo; Ogura, Yusuke; Tanida, Jun [Graduate School of Information Science and Technology, Osaka University, 1-5 Yamadaoka, Suita, Osaka 565-0871 (Japan)

    2015-07-06

    Molecular logic circuits represent a promising technology for observation and manipulation of biological systems at the molecular level. However, the implementation of molecular logic circuits for temporal and programmable operation remains challenging. In this paper, we demonstrate an optically controllable logic circuit that uses fluorescence resonance energy transfer (FRET) for signaling. The FRET-based signaling process is modulated by both molecular and optical inputs. Based on the distance dependence of FRET, the FRET pathways required to execute molecular logic operations are formed on a DNA nanostructure as a circuit based on its molecular inputs. In addition, the FRET pathways on the DNA nanostructure are controlled optically, using photoswitching fluorescent molecules to instruct the execution of the desired operation and the related timings. The behavior of the circuit can thus be controlled using external optical signals. As an example, a molecular logic circuit capable of executing two different logic operations was studied. The circuit contains functional DNAs and a DNA scaffold to construct two FRET routes for executing Input 1 AND Input 2 and Input 1 AND NOT Input 3 operations on molecular inputs. The circuit produced the correct outputs with all possible combinations of the inputs by following the light signals. Moreover, the operation execution timings were controlled based on light irradiation and the circuit responded to time-dependent inputs. The experimental results demonstrate that the circuit changes the output for the required operations following the input of temporal light signals.

  10. Sequential circuit design for radiation hardened multiple voltage integrated circuits

    Science.gov (United States)

    Clark, Lawrence T.; 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.

  11. Circuit theory and model-based inference for landscape connectivity

    Science.gov (United States)

    Hanks, Ephraim M.; Hooten, Mevin B.

    2013-01-01

    Circuit theory has seen extensive recent use in the field of ecology, where it is often applied to study functional connectivity. The landscape is typically represented by a network of nodes and resistors, with the resistance between nodes a function of landscape characteristics. The effective distance between two locations on a landscape is represented by the resistance distance between the nodes in the network. Circuit theory has been applied to many other scientific fields for exploratory analyses, but parametric models for circuits are not common in the scientific literature. To model circuits explicitly, we demonstrate a link between Gaussian Markov random fields and contemporary circuit theory using a covariance structure that induces the necessary resistance distance. This provides a parametric model for second-order observations from such a system. In the landscape ecology setting, the proposed model provides a simple framework where inference can be obtained for effects that landscape features have on functional connectivity. We illustrate the approach through a landscape genetics study linking gene flow in alpine chamois (Rupicapra rupicapra) to the underlying landscape.

  12. Simple Cell Balance Circuit

    Science.gov (United States)

    Johnson, Steven D.; Byers, Jerry W.; Martin, James A.

    2012-01-01

    A method has been developed for continuous cell voltage balancing for rechargeable batteries (e.g. lithium ion batteries). A resistor divider chain is provided that generates a set of voltages representing the ideal cell voltage (the voltage of each cell should be as if the cells were perfectly balanced). An operational amplifier circuit with an added current buffer stage generates the ideal voltage with a very high degree of accuracy, using the concept of negative feedback. The ideal voltages are each connected to the corresponding cell through a current- limiting resistance. Over time, having the cell connected to the ideal voltage provides a balancing current that moves the cell voltage very close to that ideal level. In effect, it adjusts the current of each cell during charging, discharging, and standby periods to force the cell voltages to be equal to the ideal voltages generated by the resistor divider. The device also includes solid-state switches that disconnect the circuit from the battery so that it will not discharge the battery during storage. This solution requires relatively few parts and is, therefore, of lower cost and of increased reliability due to the fewer failure modes. Additionally, this design uses very little power. A preliminary model predicts a power usage of 0.18 W for an 8-cell battery. This approach is applicable to a wide range of battery capacities and voltages.

  13. Quasi-Linear Circuit

    Science.gov (United States)

    Bradley, William; Bird, Ross; Eldred, Dennis; Zook, Jon; Knowles, Gareth

    2013-01-01

    This work involved developing spacequalifiable switch mode DC/DC power supplies that improve performance with fewer components, and result in elimination of digital components and reduction in magnetics. This design is for missions where systems may be operating under extreme conditions, especially at elevated temperature levels from 200 to 300 degC. Prior art for radiation-tolerant DC/DC converters has been accomplished utilizing classical magnetic-based switch mode converter topologies; however, this requires specific shielding and component de-rating to meet the high-reliability specifications. It requires complex measurement and feedback components, and will not enable automatic re-optimization for larger changes in voltage supply or electrical loading condition. The innovation is a switch mode DC/DC power supply that eliminates the need for processors and most magnetics. It can provide a well-regulated voltage supply with a gain of 1:100 step-up to 8:1 step down, tolerating an up to 30% fluctuation of the voltage supply parameters. The circuit incorporates a ceramic core transformer in a manner that enables it to provide a well-regulated voltage output without use of any processor components or magnetic transformers. The circuit adjusts its internal parameters to re-optimize its performance for changes in supply voltage, environmental conditions, or electrical loading at the output

  14. COCONet and TLALOCNet: Multi-hazard GNSS/Met Observatories, Enhancing Geodetic Infrastructure and the Scientific Community in Mexico and the Caribbean

    Science.gov (United States)

    Feaux, K.; Adams, D. K.; Braun, J.; Cabral-Cano, E.; Dausz, K.; Dittmann, S. T.; Fend, M.; Galetzka, J.; Mattioli, G. S.; Miller, M. M.; Normandeau, J.; Salazar-Tlaczani, L.; Sandru, J.; Serra, Y. L.; Wang, G.

    2015-12-01

    UNAVCO manages the construction of two large NSF-funded networks of geophysical instruments in Central America and the Caribbean. COCONet (Continuously Operating Caribbean Observational Network), which consists of 83 new and refurbished cGNSS/Met stations, spans the entire Caribbean region. TLALOCNet (Trans-boundary Land and Atmospheric Long-term Observational and Collaborative Network) is a similar 24-station in Mexico. Data are being used to study solid earth processes such as plate kinematics, plate boundary deformation, and the earthquake cycle; in addition, by providing more precise estimates of tropospheric water vapor to better forecast the dynamics associated with the annual Caribbean hurricane cycle and the North American monsoon, they also address atmospheric science objectives. COCONet and TLALOCNet rely on the concept of building partnerships with a range of stakeholders that support a common goal of providing free, high-quality, low-latency, open-format data and data products. As part of COCONet, UNAVCO completed installation of sea level monitoring instruments at two locations in the Caribbean Basin. Additionally, two existing sea level stations were upgraded with co-located GNSS hardware. The locations (Jamaica, Mexico, Panama, and the Dominican Republic) enhance the coverage of tide gauge instrumentation in the Caribbean region. Each station consists of tide gauge instruments (radar and pressure gauge) on a marine pier co-located with a cGNSS/Met system. A second cGNSS system is installed nearby (IOC sea level archive (ioc-sealevelmonitoring.org). We present the siting plan, construction status, and other highlights of the COCONet and TLALOCNet projects, including the establishment of regional GNSS/Met data centers in Mexico and the Caribbean.

  15. A bit serial sequential circuit

    Science.gov (United States)

    Hu, S.; Whitaker, S.

    1990-01-01

    Normally a sequential circuit with n state variables consists of n unique hardware realizations, one for each state variable. All variables are processed in parallel. This paper introduces a new sequential circuit architecture that allows the state variables to be realized in a serial manner using only one next state logic circuit. The action of processing the state variables in a serial manner has never been addressed before. This paper presents a general design procedure for circuit construction and initialization. Utilizing pass transistors to form the combinational next state forming logic in synchronous sequential machines, a bit serial state machine can be realized with a single NMOS pass transistor network connected to shift registers. The bit serial state machine occupies less area than other realizations which perform parallel operations. Moreover, the logical circuit of the bit serial state machine can be modified by simply changing the circuit input matrix to develop an adaptive state machine.

  16. Synthetic Biology: Integrated Gene Circuits

    OpenAIRE

    Nandagopal, Nagarajan; Michael B Elowitz

    2011-01-01

    A major goal of synthetic biology is to develop a deeper understanding of biological design principles from the bottom up, by building circuits and studying their behavior in cells. Investigators initially sought to design circuits “from scratch” that functioned as independently as possible from the underlying cellular system. More recently, researchers have begun to develop a new generation of synthetic circuits that integrate more closely with endogenous cellular processes. These approaches...

  17. Quantum Circuits with Mixed States

    OpenAIRE

    Aharonov, Dorit; Kitaev, Alexei; Nisan, Noam

    1998-01-01

    We define the model of quantum circuits with density matrices, where non-unitary gates are allowed. Measurements in the middle of the computation, noise and decoherence are implemented in a natural way in this model, which is shown to be equivalent in computational power to standard quantum circuits. The main result in this paper is a solution for the subroutine problem: The general function that a quantum circuit outputs is a probabilistic function, but using pure state language, such a func...

  18. Microwatt Switched Capacitor Circuit Design

    OpenAIRE

    Vittoz, E.

    1982-01-01

    The micropower CMOS implementation of the three basic components of switched capacitor circuits is discussed. Switches must be carefully designed to allow low voltage operation and compensation of clock feed-through by dummy transistors. Matched capacitors can be implemented in single polysilicon technologies primarily designed for digital micropower circuits. Excellent micropower amplifiers are realized by using simple one-stage circuits which take advantage of the special behaviour of MOS t...

  19. Designing Parity Preserving Reversible Circuits

    OpenAIRE

    Paul, Goutam; Chattopadhyay, Anupam; Chandak, Chander

    2013-01-01

    Making a reversible circuit fault-tolerant is much more difficult than classical circuit and there have been only a few works in the area of parity-preserving reversible logic design. Moreover, all of these designs are ad hoc, based on some pre-defined parity preserving reversible gates as building blocks. In this paper, we for the first time propose a novel and systematic approach towards parity preserving reversible circuits design. We provide some related theoretical results and give two a...

  20. CMOS Nonlinear Signal Processing Circuits

    OpenAIRE

    Hung,; Yu-Cherng,

    2010-01-01

    The chapter describes various nonlinear signal processing CMOS circuits, including a high reliable WTA/LTA, simple MED cell, and low-voltage arbitrary order extractor. We focus the discussion on CMOS analog circuit design with reliable, programmable capability, and low voltage operation. It is a practical problem when the multiple identical cells are required to match and realized within a single chip using a conventional process. Thus, the design of high-reliable circuit is indeed needed. Th...

  1. Secondary Circuit Start Up Chemistry Optimisation

    International Nuclear Information System (INIS)

    In a context of investment and renewal of equipment, Electricite De France (EDF) put enhanced efforts on operating practices during start-up of the secondary circuit, in order to improve operational performance and materials lifetime. This article focuses on the objective of optimizing the filling, the chemical conditioning and the thermal conditioning of the secondary fluid, while taking into account the following issues: - Limiting the time required to obtain a proper chemistry, - Limiting the amount of water and steam used, - Limiting the amount of effluent generated. The scope is all start-up conditions of secondary circuit, both after refuelling outage or fortuitous shutdowns of the plant. The recommendations produced are based on existing local procedures and good practices, which were collected and developed in order to propose a generic methodology understandable and useful both for operators, chemists and managers. (authors)

  2. 49 CFR 236.13 - Spring switch; selection of signal control circuits through circuit controller.

    Science.gov (United States)

    2010-10-01

    ... circuits through circuit controller. 236.13 Section 236.13 Transportation Other Regulations Relating to...; selection of signal control circuits through circuit controller. The control circuits of signals governing... circuit controller, or through the contacts of relay repeating the position of such circuit...

  3. Accelerating Scientific Computations using FPGAs

    Science.gov (United States)

    Pell, O.; Atasu, K.; Mencer, O.

    Field Programmable Gate Arrays (FPGAs) are semiconductor devices that contain a grid of programmable cells, which the user configures to implement any digital circuit of up to a few million gates. Modern FPGAs allow the user to reconfigure these circuits many times each second, making FPGAs fully programmable and general purpose. Recent FPGA technology provides sufficient resources to tackle scientific applications on large-scale parallel systems. As a case study, we implement the Fast Fourier Transform [1] in a flexible floating point implementation. We utilize A Stream Compiler [2] (ASC) which combines C++ syntax with flexible floating point support by providing a 'HWfloat' data-type. The resulting FFT can be targeted to a variety of FPGA platforms in FFTW-style, though not yet completely automatically. The resulting FFT circuit can be adapted to the particular resources available on the system. The optimal implementation of an FFT accelerator depends on the length and dimensionality of the FFT, the available FPGA area, the available hard DSP blocks, the FPGA board architecture, and the precision and range of the application [3]. Software-style object-orientated abstractions allow us to pursue an accelerated pace of development by maximizing re-use of design patterns. ASC allows a few core hardware descriptions to generate hundreds of different circuit variants to meet particular speed, area and precision goals. The key to achieving maximum acceleration of FFT computation is to match memory and compute bandwidths so that maximum use is made of computational resources. Modern FPGAs contain up to hundreds of independent SRAM banks to store intermediate results, providing ample scope for optimizing memory parallelism. At 175Mhz, one of Maxeler's Radix-4 FFT cores computes 4x as many 1024pt FFTs per second as a dual Pentium-IV Xeon machine running FFTW. Eight such parallel cores fit onto the largest FPGA in the Xilinx Virtex-4 family, providing a 32x speed-up over

  4. Optical integrated circuits and networks on microscale/nanoscale

    Science.gov (United States)

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

    2007-02-01

    We present an overview of our work on the design and fabrication of micro/nano-scale photonic circuits and networks on what we call "optical printed circuit boards" (O-PCBs) and "VLSI photonic integrated circuit chips"(VLSI-PICs) of generic and application-specific nature. The O-PCBs and photonic chips consist of 2-dimensional planar arrays of optical wires, circuits, and networks of micro/nano-scale to perform the functions of sensing, storing, transporting, processing, switching, routing, and distributing optical signals on flat boards or chips. We describe and discuss scientific and technological issues concerning the miniaturization, interconnection and integration of micro/nano-scale photonic devices, circuits, and networks leading to small and very large scale integration in terms of photonic scaling rules and discuss their use for the design and fabrication of the photonic integrated circuits and networks. Design rules for the miniaturization and integration of the micro/nano-photonic systems are discussed in comparison with those of the micro/nano-electronic systems. Materials include polymer/organic materials and silicon materials. Structural bases include photonic crystals, ring resonators, and plasmonic structures. Compatibility issues between diverse materials and devices are discussed especially in regard to applications. Recent progresses and examples are presented.

  5. Scientific Discoveries the Year I Was Born

    Science.gov (United States)

    Cherif, Abour

    2012-01-01

    The author has successfully used a learning activity titled "The Year I Was Born" to motivate students to conduct historical research and present key scientific discoveries from their birth year. The activity promotes writing, helps students enhance their scientific literacy, and also improves their attitude toward the learning of science. As one…

  6. Kaleidoscope: Scientific Quality Committee - final report

    DEFF Research Database (Denmark)

    Dirckinck-Holmfeld, Lone; Laurillard, Diana

    To shape a body of reference at a scientific level for the European TEL research communities. To make recommendations (i) to support a policy for the enhancement of research in Europe in this field, (ii) to survey the development of the field, and (iii) to build scientific collaboration on top...

  7. A Circuit to Demonstrate Phase Relationships in "RLC" Circuits

    Science.gov (United States)

    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…

  8. Basic electronic circuits

    CERN Document Server

    Buckley, P M

    1980-01-01

    In the past, the teaching of electricity and electronics has more often than not been carried out from a theoretical and often highly academic standpoint. Fundamentals and basic concepts have often been presented with no indication of their practical appli­ cations, and all too frequently they have been illustrated by artificially contrived laboratory experiments bearing little relationship to the outside world. The course comes in the form of fourteen fairly open-ended constructional experiments or projects. Each experiment has associated with it a construction exercise and an explanation. The basic idea behind this dual presentation is that the student can embark on each circuit following only the briefest possible instructions and that an open-ended approach is thereby not prejudiced by an initial lengthy encounter with the theory behind the project; this being a sure way to dampen enthusiasm at the outset. As the investigation progresses, questions inevitably arise. Descriptions of the phenomena encounte...

  9. A dishwasher for circuits

    CERN Multimedia

    Rosaria Marraffino

    2014-01-01

    You have always been told that electronic devices fear water. However, at the Surface Mount Devices (SMD) Workshop here at CERN all the electronic assemblies are cleaned with a machine that looks like a… dishwasher.   The circuit dishwasher. Credit: Clara Nellist.  If you think the image above shows a dishwasher, you wouldn’t be completely wrong. Apart from the fact that the whole pumping system and the case itself are made entirely from stainless steel and chemical resistant materials, and the fact that it washes electrical boards instead of dishes… it works exactly like a dishwasher. It’s a professional machine (mainly used in the pharmaceutical industry) designed to clean everything that can be washed with a water-based chemical soap. This type of treatment increases the lifetime of the electronic boards and therefore the LHC's reliability by preventing corrosion problems in the severe radiation and ozone environment of the LHC tunn...

  10. Memristor Circuits and Systems

    KAUST Repository

    Zidan, Mohammed A.

    2015-05-01

    Current CMOS-based technologies are facing design challenges related to the continuous scaling down of the minimum feature size, according to Moore’s law. Moreover, conventional computing architecture is no longer an effective way of fulfilling modern applications demands, such as big data analysis, pattern recognition, and vector processing. Therefore, there is an exigent need to shift to new technologies, at both the architecture and the device levels. Recently, memristor devices and structures attracted attention for being promising candidates for this job. Memristor device adds a new dimension for designing novel circuits and systems. In addition, high-density memristor-based crossbar is widely considered to be the essential element for future memory and bio-inspired computing systems. However, numerous challenges need to be addressed before the memristor genuinely replaces current memory and computing technologies, which is the motivation behind this research effort. In order to address the technology challenges, we begin by fabricating and modeling the memristor device. The devices fabricated at our local clean room enriched our understanding of the memristive phenomenon and enabled the experimental testing for our memristor-based circuits. Moreover, our proposed mathematical modeling for memristor behavior is an essential element for the theoretical circuit design stage. Designing and addressing the challenges of memristor systems with practical complexity, however, requires an extra step, which takes the form of a reliable and modular simulation platform. We, therefore, built a new simulation platform for the resistive crossbar, which can simulate realistic size arrays filled with real memory data. In addition, this simulation platform includes various crossbar nonidealities in order to obtain accurate simulation results. Consequently, we were able to address the significant challenges facing the high density memristor crossbar, as the building block for

  11. VLSI circuits implementing computational models of neocortical circuits.

    Science.gov (United States)

    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. PMID:22342970

  12. Ethics in Scientific Publishing

    Science.gov (United States)

    Sage, Leslie J.

    2012-08-01

    We all learn in elementary school not turn in other people's writing as if it were our own (plagiarism), and in high school science labs not to fake our data. But there are many other practices in scientific publishing that are depressingly common and almost as unethical. At about the 20 percent level authors are deliberately hiding recent work -- by themselves as well as by others -- so as to enhance the apparent novelty of their most recent paper. Some people lie about the dates the data were obtained, to cover up conflicts of interest, or inappropriate use of privileged information. Others will publish the same conference proceeding in multiple volumes, or publish the same result in multiple journals with only trivial additions of data or analysis (self-plagiarism). These shady practices should be roundly condemned and stopped. I will discuss these and other unethical actions I have seen over the years, and steps editors are taking to stop them.

  13. Demonstrations with an "LCR" Circuit

    Science.gov (United States)

    Kraftmakher, Yaakov

    2011-01-01

    The "LCR" circuit is an important topic in the course of electricity and magnetism. Papers in this field consider mainly the forced oscillations and resonance. Our aim is to show how to demonstrate the free and self-excited oscillations in an "LCR" circuit. (Contains 4 figures.)

  14. Improved simulation of stabilizer circuits

    International Nuclear Information System (INIS)

    The Gottesman-Knill theorem says that a stabilizer circuit - that is, a quantum circuit consisting solely of controlled-NOT (CNOT), Hadamard, and phase gates - can be simulated efficiently on a classical computer. This paper improves that theorem in several directions. First, by removing the need for Gaussian elimination, we make the simulation algorithm much faster at the cost of a factor of 2 increase in the number of bits needed to represent a state. We have implemented the improved algorithm in a freely available program called CHP (CNOT-Hadamard-phase), which can handle thousands of qubits easily. Second, we show that the problem of simulating stabilizer circuits is complete for the classical complexity class +L, which means that stabilizer circuits are probably not even universal for classical computation. Third, we give efficient algorithms for computing the inner product between two stabilizer states, putting any n-qubit stabilizer circuit into a 'canonical form' that requires at most O(n2/log n) gates, and other useful tasks. Fourth, we extend our simulation algorithm to circuits acting on mixed states, circuits containing a limited number of nonstabilizer gates, and circuits acting on general tensor-product initial states but containing only a limited number of measurements

  15. Pharmacokinetics and "RC" Circuit Concepts

    Science.gov (United States)

    De Cock, Mieke; Janssen, Paul

    2013-01-01

    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…

  16. Postirradiation Effects In Integrated Circuits

    Science.gov (United States)

    Shaw, David C.; Barnes, Charles E.

    1993-01-01

    Two reports discuss postirradiation effects in integrated circuits. Presents examples of postirradiation measurements of performances of integrated circuits of five different types: dual complementary metal oxide/semiconductor (CMOS) flip-flop; CMOS analog multiplier; two CMOS multiplying digital-to-analog converters; electrically erasable programmable read-only memory; and semiconductor/oxide/semiconductor octal buffer driver.

  17. A high precision CMOS weak current readout circuit

    International Nuclear Information System (INIS)

    This paper presents a high precision CMOS weak current readout circuit. This circuit is capable of converting a weak current into a frequency signal for amperometric measurements with high precision and further delivering a 10-bit digital output. A fast stabilization-enhanced potentiostat has been proposed in the design, which is used to maintain a constant bias potential for amperometric biochemical sensors. A technique based on source voltage shifting that reduces the leakage current of the MOS transistor to the reverse diode leakage level at room temperature was employed in the circuit. The chip was fabricated in the 0.35 μm chartered CMOS process, with a single 3.3 V power supply. The interface circuit maintains a dynamic range of more than 100 dB. Currents from 1 pA to 300 nA can be detected with a maximum nonlinearity of 0.3% over the full scale.

  18. Demultiplexer circuit for neural stimulation

    Science.gov (United States)

    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.

  19. Electronic design with integrated circuits

    Science.gov (United States)

    Comer, D. J.

    The book is concerned with the application of integrated circuits and presents the material actually needed by the system designer to do an effective job. The operational amplifier (op amp) is discussed, taking into account the electronic amplifier, the basic op amp, the practical op amp, analog applications, and digital applications. Digital components are considered along with combinational logic, digital subsystems, the microprocessor, special circuits, communications, and integrated circuit building blocks. Attention is given to logic gates, logic families, multivibrators, the digital computer, digital methods, communicating with a computer, computer organization, register and timing circuits for data transfer, arithmetic circuits, memories, the microprocessor chip, the control unit, communicating with the microprocessor, examples of microprocessor architecture, programming a microprocessor, the voltage-controlled oscillator, the phase-locked loop, analog-to-digital conversion, amplitude modulation, frequency modulation, pulse and digital transmission, the semiconductor diode, the bipolar transistor, and the field-effect transistor.

  20. 49 CFR 236.728 - Circuit, trap.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, trap. 236.728 Section 236.728... Circuit, trap. A term applied to a circuit used where it is desirable to provide a track circuit but where it is impracticable to maintain a track circuit....

  1. Frontiers in Planar Lightwave Circuit Technology Design, Simulation, and Fabrication

    CERN Document Server

    Janz, Siegfried; Tanev, Stoyan

    2005-01-01

    This book is the result of the NATO Advanced Research Workshop on Frontiers in Planar Lightwave Circuit Technology, which took place in Ottawa, Canada from September 21-25, 2004. Many of the world’s leading experts in integrated photonic design, theory and experiment were invited to give lectures in their fields of expertise, and participate in discussions on current research and applications, as well as the new directions planar lightwave circuit technology is evolving towards. The sum of their contributions to this book constitutes an excellent record of many key issues and scientific problems in planar lightwave circuit research at the time of writing. In this volume the reader will find detailed overviews of experimental and theoretical work in high index contrast waveguide systems, micro-optical resonators, nonlinear optics, and advanced optical simulation methods, as well as articles describing emerging applications of integrated optics for medical and biological applications.

  2. Light Sources and Ballast Circuits

    Science.gov (United States)

    Yorifuji, Takashi; Sakai, Makoto; Yasuda, Takeo; Maehara, Akiyoshi; Okada, Atsunori; Gouriki, Takeshi; Mannami, Tomoaki

    discharge models were reported. Further, studies on ultra high-pressure mercury lamps as light sources for projectors are becoming the mainstream of HID lamp related researches. For high-pressure sodium lamps, many studies on plant growing and pest control utilizing low insect attracting aspects were also reported in 2006. Additionally, for discharge lamps, the minimum sustaining electric power for arc tubes employed in electrode-less compact fluorescent lamps was investigated. For Hg-free rare-gas fluorescent lamps, a luminance of 10,000cd/m2 was attained by a 1 meter-long external duplex spiral electrode prototype using Xe/Ne barrier discharge. As to startup circuits, the commercialization of energy saving and high value added products mainly associated with fluorescent lamps and HID lamps are becoming common. Further, the miniaturization of startup circuits for self electronic-ballasted lamps has advanced. Speaking of the overall light sources and startup circuits in 2006 and with the enforcement of RoHS in Europe in July, the momentum toward hazardous substance-free and energy saving initiatives has been enhanced from the perspective of protecting the global environment. It is anticipated that similar restrictions will be globally enforced in the future.

  3. PREDON Scientific Data Preservation 2014

    Science.gov (United States)

    Diaconu, C.; Kraml, S.; Surace, C.; Chateigner, D.; Libourel, T.; Laurent, A.; Lin, Y.; Schaming, M.; Benbernou, S.; Lebbah, M.; Boucon, D.; Cérin, C.; Azzag, H.; Mouron, P.; Nief, J.-Y.; Coutin, S.; Beckmann, V.

    Scientific data collected with modern sensors or dedicated detectors exceed very often the perimeter of the initial scientific design. These data are obtained more and more frequently with large material and human efforts. A large class of scientific experiments are in fact unique because of their large scale, with very small chances to be repeated and to superseded by new experiments in the same domain: for instance high energy physics and astrophysics experiments involve multi-annual developments and a simple duplication of efforts in order to reproduce old data is simply not affordable. Other scientific experiments are in fact unique by nature: earth science, medical sciences etc. since the collected data is "time-stamped" and thereby non-reproducible by new experiments or observations. In addition, scientific data collection increased dramatically in the recent years, participating to the so-called "data deluge" and inviting for common reflection in the context of "big data" investigations. The new knowledge obtained using these data should be preserved long term such that the access and the re-use are made possible and lead to an enhancement of the initial investment. Data observatories, based on open access policies and coupled with multi-disciplinary techniques for indexing and mining may lead to truly new paradigms in science. It is therefore of outmost importance to pursue a coherent and vigorous approach to preserve the scientific data at long term. The preservation remains nevertheless a challenge due to the complexity of the data structure, the fragility of the custom-made software environments as well as the lack of rigorous approaches in workflows and algorithms. To address this challenge, the PREDON project has been initiated in France in 2012 within the MASTODONS program: a Big Data scientific challenge, initiated and supported by the Interdisciplinary Mission of the National Centre for Scientific Research (CNRS). PREDON is a study group formed by

  4. Acute Effects of Three Different Circuit Weight Training Protocols on Blood Lactate, Heart Rate, and Rating of Perceived Exertion in Recreationally Active Women

    OpenAIRE

    Skidmore, Brook L.; Jones, Margaret T; Mark Blegen; Matthews, Tracey D.

    2012-01-01

    Interval and circuit weight training are popular training methods for maximizing time-efficiency, and are purported to deliver greater physiological benefits faster than traditional training methods. Adding interval training into a circuit weight-training workout may further enhance the benefits of circuit weight training by placing increased demands upon the cardiovascular system. Our purpose was to compare acute effects of three circuit weight training protocols 1) traditional circuit weigh...

  5. On the Enhancement of Scientific Performance Evaluation in Public Security Organs%对增强公安机关绩效考评科学性的思考

    Institute of Scientific and Technical Information of China (English)

    刘乃兴

    2015-01-01

    Guided by the 3rd Plenary Session of 18th CPC Central Committee, and based on summarizing the work experience of performance evaluation, the article analyzes the role and existing problems of performance evaluation from theory and practice, discusses three principles followed by performance evaluation with enhancing the scientific performance evaluation in public security organs as the center, determines eight relations in evaluation content and settles three basic questions in the implementation of performance evaluation.%文章以党的十八届三中全会文件为指导,在总结绩效考评工作体会的基础上,从理论与实践的结合上分析了绩效考评的作用和存在的问题,围绕增强公安机关绩效考评科学性这个中心,论述了绩效考评应该遵循的三条原则、确定考评内容应处理好的八个关系以及实施考评应处理好的三个基本问题。

  6. Systems Sustainability: Implementation of Enhanced Maintenance Programs at the Kurchatov Institute, the All-Russian Research Institute of Experimental physics (VNIIEF) and the All-Russian Scientific Institute for Technical Physics (VNIITF)

    International Nuclear Information System (INIS)

    Implementation of quality maintenance programs is essential to enhancing sustainable continuous operations of United States funded Materials Protection, Control and Accountability (MPC and A) equipment/systems upgrades at various Russian nuclear facilities. An effective maintenance program is expected to provide assurances to both parties for achieving maximum continuous systems operations with minimum down time. To be effective, the program developed must focus on minimum down time for any part of a system. Minimum down time is realized through the implementation of a quality maintenance program that includes preventative maintenance, necessary diagnostic tools, properly trained technical staff, and an in-house inventory of required spare parts for repairing the impacted component of the system. A centralized maintenance management program is logistically essential for the success of this effort because of the large volume of MPC and A equipment/systems installed at those sites. This paper will discuss current programs and conditions at the Russian Research Center-Kurchatov Institute, the All-Russian Scientific Institute for Technical Physics and the All-Russian Research Institute of Experimental Physics and will address those steps necessary to implement an upgraded program at those sites

  7. Variational integrators for electric circuits

    International Nuclear Information System (INIS)

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

  8. Double functions of porous TiO2 electrodes on CH3NH3PbI3 perovskite solar cells: Enhancement of perovskite crystal transformation and prohibition of short circuiting

    Directory of Open Access Journals (Sweden)

    Govindhasamy Murugadoss

    2014-08-01

    Full Text Available In order to analyze the crystal transformation from hexagonal PbI2 to CH3NH3PbI3 by the sequential (two-step deposition process, perovskite CH3NH3PbI3 layers were deposited on flat and/or porous TiO2 layers. Although the narrower pores using small nanoparticles prohibited the effective transformation, the porous-TiO2 matrix was able to help the crystal transformation of PbI2 to CH3NH3PbI3 by sequential two-step deposition. The resulting PbI2 crystals in porous TiO2 electrodes did not deteriorate the photovoltaic effects. Moreover, it is confirmed that the porous TiO2 electrode had served the function of prohibiting short circuits between working and counter electrodes in perovskite solar cells.

  9. 30 CFR 75.800 - High-voltage circuits; circuit breakers.

    Science.gov (United States)

    2010-07-01

    ... 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. High-voltage circuits entering the underground area of any coal mine shall be protected by suitable circuit breakers of adequate interrupting...

  10. Multiband RF circuits and techniques for wireless transmitters

    CERN Document Server

    Chen, Wenhua; Ghannouchi, Fadhel M

    2016-01-01

    This book introduces systematic design methods for passive and active RF circuits and techniques, including state-of-the-art digital enhancement techniques. As the very first book dedicated to multiband RF circuits and techniques, this work provides an overview of the evolution of transmitter architecture and discusses current digital predistortion techniques. Readers will find a collection of novel research ideas and new architectures in concurrent multiband power dividers, power amplifiers and related digital enhancement techniques. This book will be of great interest to academic researchers, R&D engineers, wireless transmitter and protocol designers, as well as graduate students who wish to learn the core architectures, principles and methods of multiband RF circuits and techniques. .

  11. The Maplin electronic circuits handbook

    CERN Document Server

    Tooley, Michael

    2015-01-01

    The Maplin Electronic Circuits Handbook provides pertinent data, formula, explanation, practical guidance, theory and practical guidance in the design, testing, and construction of electronic circuits. This book discusses the developments in electronics technology techniques.Organized into 11 chapters, this book begins with an overview of the common types of passive component. This text then provides the reader with sufficient information to make a correct selection of passive components for use in the circuits. Other chapters consider the various types of the most commonly used semiconductor

  12. Scientific bases of human-machine communication by voice.

    OpenAIRE

    Schafer, R W

    1995-01-01

    The scientific bases for human-machine communication by voice are in the fields of psychology, linguistics, acoustics, signal processing, computer science, and integrated circuit technology. The purpose of this paper is to highlight the basic scientific and technological issues in human-machine communication by voice and to point out areas of future research opportunity. The discussion is organized around the following major issues in implementing human-machine voice communication systems: (i...

  13. Equivalent Circuit Modeling of a Rotary Piezoelectric Motor

    DEFF Research Database (Denmark)

    El, Ghouti N.; Helbo, Jan

    2000-01-01

    In this paper, an enhanced equivalent circuit model of a rotary traveling wave piezoelectric ultrasonic motor "shinsei type USR60" is derived. The modeling is performed on the basis of an empirical approach combined with the electrical network method and some simplification assumptions about...

  14. Equivalent Circuit Modeling of a Rotary Piezoelectric Motor

    DEFF Research Database (Denmark)

    El, Ghouti N.; Helbo, Jan

    2000-01-01

    In this paper, an enhanced equivalent circuit model of a rotary traveling wave piezoelectric ultrasonic motor "shinsei type USR60" is derived. The modeling is performed on the basis of an empirical approach combined with the electrical network method and some simplification assumptions about the...

  15. Wireless communications circuits and systems

    CERN Document Server

    Sun, Yichuang

    2004-01-01

    This new book examines integrated circuits, systems and transceivers for wireless and mobile communications. It covers the most recent developments in key RF, IF, analogue, mixed-signal components and single-chip transceivers in CMOS technology.

  16. Discharge quenching circuit for counters

    International Nuclear Information System (INIS)

    A circuit for quenching discharges in gas-discharge detectors with working voltage of 3-5 kV based on transistors operating in the avalanche mode is described. The quenching circuit consists of a coordinating emitter follower, amplifier-shaper for avalanche key cascade control which changes potential on the counter electrodes and a shaper of discharge quenching duration. The emitter follower is assembled according to a widely used flowsheet with two transistors. The circuit permits to obtain a rectangular quenching pulse with front of 100 ns and an amplitude of up to 3.2 kV at duration of 500 μm-8 ms. Application of the quenching circuit described permits to obtain countering characteristics with the slope less than or equal to 0.02%/V and plateau extent greater than or equal to 300 V

  17. Design of HTS RSFQ circuits

    International Nuclear Information System (INIS)

    After more than a decade of research in single flux quantum (SFQ) circuits, a high level of understanding the requirements for designing them with high-Tc superconductors (HTS) has been gained. Recently, the fabrication processes are being developed to be more and more in accordance with practical requirements for the design of real digital circuits. The contribution describes the complex relationship of desired high operation temperature and required low bit-error probability on a quantitative level. Suitable guidelines for circuit dimensioning are given. The discussion is oriented at one of the contemporary technological approaches. It is concluded that, despite some previous estimations, HTS SFQ circuits can work stable theoretically also at a relatively high operation temperature

  18. Extensional Uniformity for Boolean Circuits

    CERN Document Server

    McKenzie, Pierre; Vollmer, Heribert

    2008-01-01

    Imposing an extensional uniformity condition on a non-uniform circuit complexity class C means simply intersecting C with a uniform class L. By contrast, the usual intensional uniformity conditions require that a resource-bounded machine be able to exhibit the circuits in the circuit family defining C. We say that (C,L) has the "Uniformity Duality Property" if the extensionally uniform class C \\cap L can be captured intensionally by means of adding so-called "L-numerical predicates" to the first-order descriptive complexity apparatus describing the connection language of the circuit family defining C. This paper exhibits positive instances and negative instances of the Uniformity Duality Property.

  19. Circuit design on plastic foils

    CERN Document Server

    Raiteri, Daniele; Roermund, Arthur H M

    2015-01-01

    This book illustrates a variety of circuit designs on plastic foils and provides all the information needed to undertake successful designs in large-area electronics.  The authors demonstrate architectural, circuit, layout, and device solutions and explain the reasons and the creative process behind each. Readers will learn how to keep under control large-area technologies and achieve robust, reliable circuit designs that can face the challenges imposed by low-cost low-temperature high-throughput manufacturing.   • Discusses implications of problems associated with large-area electronics and compares them to standard silicon; • Provides the basis for understanding physics and modeling of disordered material; • Includes guidelines to quickly setup the basic CAD tools enabling efficient and reliable designs; • Illustrates practical solutions to cope with hard/soft faults, variability, mismatch, aging and bias stress at architecture, circuit, layout, and device levels.

  20. Practical circuits with Physarum Wires

    OpenAIRE

    Whiting, James G. H.; Mayne, Richard; Moody, Nadine; Costello, Ben de Lacy; Adamatzky, Andrew

    2015-01-01

    Purpose: Protoplasmic tubes of Physarum polycephalum, also know as Physarum Wires (PW), have been previously suggested as novel bio- electronic components. Until recently, practical examples of electronic circuits using PWs have been limited. These PWs have been shown to be self repairing, offering significant advantage over traditional electronic components. This article documents work performed to produce practical circuits using PWs. Method: We have demonstrated through manufacture and tes...

  1. An improved RF circuit for Overhauser magnetometer excitation

    Science.gov (United States)

    Zheng, Di; Zhang, Shuang; Guo, Xin; Fu, Haoyang

    2015-08-01

    Overhauser magnetometer is a high-precision device for magnetostatic field measurement, which can be used in a wide variety of purposes: UXO detection, pipeline mapping and other engineering and environmental applications. Traditional proton magnetometer adopts DC polarization, suffering from low polarization efficiency, high power consumption and low signal noise ratio (SNR). Compared with the traditional proton magnetometer, nitroxide free radicals are used for dynamic nuclear polarization (DNP) to enhance nuclear magnetic resonance (NMR). RF excitation is very important for electron resonance in nitrogen oxygen free radical solution, and it is primarily significant for the obtention of high SNR signal and high sensitive field observation. Therefore, RF excitation source plays a crucial role in the development of Overhauser magnetometer. In this paper, an improved design of a RF circuit is discussed. The new RF excitation circuit consists of two parts: Quartz crystal oscillator circuit and RF power amplifier circuit. Simulation and optimization designs for power amplifier circuit based on software ADS are presented. Finally we achieve a continuous and stable sine wave of 60MHz with 1-2.5 W output power, and the second harmonic suppression is close to -20dBc. The improved RF circuit has many merits such as small size, low-power consumption and high efficiency, and it can be applied to Overhauser magnetometer to obtain high sensitive field observation.

  2. Getting Healthy Scientifically

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Recently,Zhao Zhixin,a Beijing-based instructor on scientific bodybuilding and public sport,was interviewed by China Youth Daily,sharing his views on how to get healthy scientifically.Edited excerpts follow:

  3. Receiver Gain Modulation Circuit

    Science.gov (United States)

    Jones, Hollis; Racette, Paul; Walker, David; Gu, Dazhen

    2011-01-01

    A receiver gain modulation circuit (RGMC) was developed that modulates the power gain of the output of a radiometer receiver with a test signal. As the radiometer receiver switches between calibration noise references, the test signal is mixed with the calibrated noise and thus produces an ensemble set of measurements from which ensemble statistical analysis can be used to extract statistical information about the test signal. The RGMC is an enabling technology of the ensemble detector. As a key component for achieving ensemble detection and analysis, the RGMC has broad aeronautical and space applications. The RGMC can be used to test and develop new calibration algorithms, for example, to detect gain anomalies, and/or correct for slow drifts that affect climate-quality measurements over an accelerated time scale. A generalized approach to analyzing radiometer system designs yields a mathematical treatment of noise reference measurements in calibration algorithms. By treating the measurements from the different noise references as ensemble samples of the receiver state, i.e. receiver gain, a quantitative description of the non-stationary properties of the underlying receiver fluctuations can be derived. Excellent agreement has been obtained between model calculations and radiometric measurements. The mathematical formulation is equivalent to modulating the gain of a stable receiver with an externally generated signal and is the basis for ensemble detection and analysis (EDA). The concept of generating ensemble data sets using an ensemble detector is similar to the ensemble data sets generated as part of ensemble empirical mode decomposition (EEMD) with exception of a key distinguishing factor. EEMD adds noise to the signal under study whereas EDA mixes the signal with calibrated noise. It is mixing with calibrated noise that permits the measurement of temporal-functional variability of uncertainty in the underlying process. The RGMC permits the evaluation of EDA by

  4. What is scientific misconduct?

    DEFF Research Database (Denmark)

    Hansen, Vagn Lundsgaard

    2006-01-01

    Selected examples from history are discussed to illustrate the many difficulties in judging scientific behavior. Scientific misconduct is not an a priori given concept but must first be defined. The definitions of scientific misconduct used in the USA and in Denmark are discussed as examples....

  5. 3 CFR - Scientific Integrity

    Science.gov (United States)

    2010-01-01

    ... 3 The President 1 2010-01-01 2010-01-01 false Scientific Integrity Presidential Documents Other Presidential Documents Memorandum of March 9, 2009 Scientific Integrity Memorandum for the Heads of Executive Departments and Agencies Science and the scientific process must inform and guide decisions of...

  6. WWW: The Scientific Method

    Science.gov (United States)

    Blystone, Robert V.; Blodgett, Kevin

    2006-01-01

    The scientific method is the principal methodology by which biological knowledge is gained and disseminated. As fundamental as the scientific method may be, its historical development is poorly understood, its definition is variable, and its deployment is uneven. Scientific progress may occur without the strictures imposed by the formal…

  7. 46 CFR 169.670 - Circuit breakers.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Circuit breakers. 169.670 Section 169.670 Shipping COAST... 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...

  8. Tunable circuit for tunable capacitor devices

    Science.gov (United States)

    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.

  9. Equivalence Checking of Hierarchical Combinational Circuits

    DEFF Research Database (Denmark)

    Williams, Poul Frederick; Hulgaard, Henrik; Andersen, Henrik Reif

    1999-01-01

    This paper presents a method for verifying that two hierarchical combinational circuits implement the same Boolean functions. The key new feature of the method is its ability to exploit the modularity of circuits to reuse results obtained from one part of the circuits in other parts. We demonstrate...... our method on large adder and multiplier circuits....

  10. Multi-Layer E-Textile Circuits

    Science.gov (United States)

    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.

  11. Sub-100nm strained Si CMOS: device performance and circuit behavior

    OpenAIRE

    Yang, L; J. R. Watling; Asenov, A; Barken, J. R.; Roy, S

    2004-01-01

    Using comprehensive device simulations, performance enhancement of sub-100nm strained Si MOSFETs has been investigated. Circuit behavior of conventional Si, strained Si, conventional Si SOI and strained SOI ring oscillators has been assessed.

  12. Acquisition of Scientific Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Noland, Lynn [Director, Sponsored Programs

    2014-05-16

    Whitworth University constructed a 63,00 sq. ft. biology and chemistry building which opened in the Fall of 2011. This project provided for new state-of-the-art science instrumentation enabling Whitworth students to develop skills and knowledge that are directly transferable to practical applications thus enhancing Whitworth student's ability to compete and perform in the scientific workforce. Additionally, STEM faculty undertake outreach programs in the area schools, bringing students to our campus to engage in activities with our science students. The ability to work with insturmentation that is current helps to make science exciting for middle school and high school students and gets them thinking about careers in science. 14 items were purchased following the university's purchasing policy, that benefit instruction and research in the departments of biology, chemistry, and health sciences. They are: Cadaver Dissection Tables with Exhaust Chamber and accessories, Research Microscope with DF DIC, Phase and Fluorescence illumination with DP72 Camera, Microscope with Fluorescence, Microcomputer controlled ultracentrifuge, Ultracentrifuge rotor, Variable Temperature steam pressure sterilizer, Alliance APLC System, DNA Speedvac, Gel Cocumentation System, BioPac MP150, Glovebox personal workstation,Lyophilizer, Nano Drop 2000/2000c Spectrophotometer, C02 Incubator.

  13. Comparison between four piezoelectric energy harvesting circuits

    Institute of Scientific and Technical Information of China (English)

    Jinhao QIU; Hao JIANG; Hongli JI; Kongjun ZHU

    2009-01-01

    This paper investigates and compares the efficiencies of four different interfaces for vibration-based energy harvesting systems. Among those four circuits, two circuits adopt the synchronous switching technique, in which the circuit is switched synchronously with the vibration. In this study, a simple source-less trigger circuit used to control the synchronized switch is proposed and two interface circuits of energy harvesting systems are designed based on the trigger circuit. To validate the effectiveness of the proposed circuits, an experimental system was established and the power harvested by those circuits from a vibration beam was measured. Experimental results show that the two new circuits can increase the harvested power by factors 2.6 and 7, respectively, without consuming extra power in the circuits.

  14. Improved Simulation of Stabilizer Circuits

    CERN Document Server

    Aaronson, S; Aaronson, Scott; Gottesman, Daniel

    2004-01-01

    The Gottesman-Knill theorem says that a stabilizer circuit -- that is, a quantum circuit consisting solely of CNOT, Hadamard, and phase gates -- can be simulated efficiently on a classical computer. This paper improves that theorem in several directions. * By removing the need for Gaussian elimination, we make the simulation algorithm much faster at the cost of a factor-2 increase in the number of bits needed to represent a state. We have implemented the improved algorithm in a freely-available program called CHP (CNOT-Hadamard-Phase), which can handle thousands of qubits easily. * We show that the problem of simulating stabilizer circuits is complete for the classical complexity class ParityL, which means that stabilizer circuits are probably not even universal for classical computation. * We give efficient algorithms for computing the inner product between two stabilizer states, putting any n-qubit stabilizer circuit into a "canonical form" that requires at most O(n^2/log n) gates, and other useful tasks. *...

  15. A New Method for Constructing Circuit Codes

    OpenAIRE

    Byrnes, Kevin M.

    2016-01-01

    Circuit codes are constructed from induced cycles in the graph of the $n$ dimensional hypercube. They are both theoretically and practically important, as circuit codes can be used as error correcting codes. When constructing circuit codes, the length of the cycle determines its accuracy and a parameter called the spread determines how many errors it can detect. We present a new method for constructing a circuit code of spread $k+1$ from a circuit code of spread $k$. This method leads to reco...

  16. Instrumentation and test gear circuits manual

    CERN Document Server

    Marston, R M

    2013-01-01

    Instrumentation and Test Gear Circuits Manual provides diagrams, graphs, tables, and discussions of several types of practical circuits. The practical circuits covered in this book include attenuators, bridges, scope trace doublers, timebases, and digital frequency meters. Chapter 1 discusses the basic instrumentation and test gear principles. Chapter 2 deals with the design of passive attenuators, and Chapter 3 with passive and active filter circuits. The subsequent chapters tackle 'bridge' circuits, analogue and digital metering techniques and circuitry, signal and waveform generation, and p

  17. 30 CFR 77.800 - High-voltage circuits; circuit breakers.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-voltage circuits; circuit breakers. 77.800... COAL MINES Surface High-Voltage Distribution § 77.800 High-voltage circuits; circuit breakers. High-voltage circuits supplying power to portable or mobile equipment shall be protected by suitable...

  18. 30 CFR 77.506 - Electric equipment and circuits; overload and short-circuit protection.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric equipment and circuits; overload and short-circuit protection. 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...

  19. 49 CFR 236.5 - Design of control circuits on closed circuit principle.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Design of control circuits on closed circuit..., AND APPLIANCES Rules and Instructions: All Systems General § 236.5 Design of control circuits on closed circuit principle. All control circuits the functioning of which affects safety of train...

  20. A Current-Mode Common-Mode Feedback Circuit (CMFB) with Rail-to-Rail Operation

    Science.gov (United States)

    Suadet, Apirak; Kasemsuwan, Varakorn

    2011-03-01

    This paper presents a current-mode common-mode feedback (CMFB) circuit with rail-to-rail operation. The CMFB is a stand-alone circuit, which can be connected to any low voltage transconductor without changing or upsetting the existing circuit. The proposed CMFB employs current mirrors, operating as common-mode detector and current amplifier to enhance the loop gain of the CMFB. The circuit employs positive feedback to enhance the output impedance and gain. The circuit has been designed using a 0.18 μm CMOS technology under 1V supply and analyzed using HSPICE with BSIM3V3 device models. A pseudo-differential amplifier using two common sources and the proposed CMFB shows rail to rail output swing (± 0.7 V) with low common-mode gain (-36 dB) and power dissipation of 390 μW.

  1. Fault Testing for Reversible Circuits

    CERN Document Server

    Patel, K N; Markov, I L; Patel, Ketan N.; Hayes, John P.; Markov, Igor L.

    2004-01-01

    Applications of reversible circuits can be found in the fields of low-power computation, cryptography, communications, digital signal processing, and the emerging field of quantum computation. Furthermore, prototype circuits for low-power applications are already being fabricated in CMOS. Regardless of the eventual technology adopted, testing is sure to be an important component in any robust implementation. We consider the test set generation problem. Reversibility affects the testing problem in fundamental ways, making it significantly simpler than for the irreversible case. For example, we show that any test set that detects all single stuck-at faults in a reversible circuit also detects all multiple stuck-at faults. We present efficient test set constructions for the standard stuck-at fault model as well as the usually intractable cell-fault model. We also give a practical test set generation algorithm, based on an integer linear programming formulation, that yields test sets approximately half the size o...

  2. Multiplication circuit for particle identification

    International Nuclear Information System (INIS)

    After having commented some characteristics of the particles present in a cyclotron, and their interactions, this report addresses the development and the implementation of a method and a device for selecting and counting particles. The author presents the principle and existing techniques of selection. In comparison with an existing device, the proportional counter and the scintillator are replaced by junctions: a surface barrier type junction (a silicon N layer with a very thin oxygen layer playing the role of the P layer), and lithium-based junction (a silicon P type layer made intrinsic by migration of lithium). The author then describes the developed circuit and assembly (background of the choice of a multiplication circuit), and their operation. In the next part, he presents the performed tests and discuses the obtained results. He finally outlines the benefits of the herein presented circuit

  3. Vertically Integrated Circuits at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Deptuch, Grzegorz; Demarteau, Marcel; Hoff, James; Lipton, Ronald; Shenai, Alpana; Trimpl, Marcel; Yarema, Raymond; Zimmerman, Tom; /Fermilab

    2009-01-01

    The exploration of the vertically integrated circuits, also commonly known as 3D-IC technology, for applications in radiation detection started at Fermilab in 2006. This paper examines the opportunities that vertical integration offers by looking at various 3D designs that have been completed by Fermilab. The emphasis is on opportunities that are presented by through silicon vias (TSV), wafer and circuit thinning and finally fusion bonding techniques to replace conventional bump bonding. Early work by Fermilab has led to an international consortium for the development of 3D-IC circuits for High Energy Physics. The consortium has submitted over 25 different designs for the Fermilab organized MPW run organized for the first time.

  4. Additive Manufacturing of Hybrid Circuits

    Science.gov (United States)

    Sarobol, Pylin; Cook, Adam; Clem, Paul G.; Keicher, David; Hirschfeld, Deidre; Hall, Aaron C.; Bell, Nelson S.

    2016-07-01

    There is a rising interest in developing functional electronics using additively manufactured components. Considerations in materials selection and pathways to forming hybrid circuits and devices must demonstrate useful electronic function; must enable integration; and must complement the complex shape, low cost, high volume, and high functionality of structural but generally electronically passive additively manufactured components. This article reviews several emerging technologies being used in industry and research/development to provide integration advantages of fabricating multilayer hybrid circuits or devices. First, we review a maskless, noncontact, direct write (DW) technology that excels in the deposition of metallic colloid inks for electrical interconnects. Second, we review a complementary technology, aerosol deposition (AD), which excels in the deposition of metallic and ceramic powder as consolidated, thick conformal coatings and is additionally patternable through masking. Finally, we show examples of hybrid circuits/devices integrated beyond 2-D planes, using combinations of DW or AD processes and conventional, established processes.

  5. Design automation for integrated circuits

    Science.gov (United States)

    Newell, S. B.; de Geus, A. J.; Rohrer, R. A.

    1983-04-01

    Consideration is given to the development status of the use of computers in automated integrated circuit design methods, which promise the minimization of both design time and design error incidence. Integrated circuit design encompasses two major tasks: error specification, in which the goal is a logic diagram that accurately represents the desired electronic function, and physical specification, in which the goal is an exact description of the physical locations of all circuit elements and their interconnections on the chip. Design automation not only saves money by reducing design and fabrication time, but also helps the community of systems and logic designers to work more innovatively. Attention is given to established design automation methodologies, programmable logic arrays, and design shortcuts.

  6. Nuclear sensor signal processing circuit

    Science.gov (United States)

    Kallenbach, Gene A.; Noda, Frank T.; Mitchell, Dean J.; Etzkin, Joshua L.

    2007-02-20

    An apparatus and method are disclosed for a compact and temperature-insensitive nuclear sensor that can be calibrated with a non-hazardous radioactive sample. The nuclear sensor includes a gamma ray sensor that generates tail pulses from radioactive samples. An analog conditioning circuit conditions the tail-pulse signals from the gamma ray sensor, and a tail-pulse simulator circuit generates a plurality of simulated tail-pulse signals. A computer system processes the tail pulses from the gamma ray sensor and the simulated tail pulses from the tail-pulse simulator circuit. The nuclear sensor is calibrated under the control of the computer. The offset is adjusted using the simulated tail pulses. Since the offset is set to zero or near zero, the sensor gain can be adjusted with a non-hazardous radioactive source such as, for example, naturally occurring radiation and potassium chloride.

  7. Circuit model of Rimfire switch

    International Nuclear Information System (INIS)

    A cascade gaps circuit model for Rimfire switch has been developed. The circuit model includes all stray capacitances and spark channel on-state conduction characteristics. It can not only describe the behavior of Rimfire switch, but also allow analysis of the time varying voltage and current at each part of the switch, describing the internal characters of the switch. PSpice was used to implement the cascade gaps circuit model and simulate a 700 kV Rimfire switch. The simulation shows that, the voltage of the whole switch will be higher than 700 kV when the laser triggered section has broken down but all cascade gaps keep dielectric, and the voltage of all gaps attenuates with high frequency oscillation. (authors)

  8. Disinhibition, a Circuit Mechanism for Associative Learning and Memory.

    Science.gov (United States)

    Letzkus, Johannes J; Wolff, Steffen B E; Lüthi, Andreas

    2015-10-21

    Although a wealth of data have elucidated the structure and physiology of neuronal circuits, we still only have a very limited understanding of how behavioral learning is implemented at the network level. An emerging crucial player in this implementation is disinhibition--a transient break in the balance of excitation and inhibition. In contrast to the widely held view that the excitation/inhibition balance is highly stereotyped in cortical circuits, recent findings from behaving animals demonstrate that salient events often elicit disinhibition of projection neurons that favors excitation and thereby enhances their activity. Behavioral functions ranging from auditory fear learning, for which most data are available to date, to spatial navigation are causally linked to disinhibition in different compartments of projection neurons, in diverse cortical areas and at timescales ranging from milliseconds to days, suggesting that disinhibition is a conserved circuit mechanism contributing to learning and memory expression. PMID:26494276

  9. Rapid cycling synchrotron magnet with separate ac and dc circuit

    International Nuclear Information System (INIS)

    In present rapid cycling synchrotron magnets ac and dc currents flow in the same coil to give the desired field. The circuit reactance is made zero at dc and the operating frequency by running the magnet in series with an external parallel resonant LC current. We propose to return the ac flux in a gap next to the synchrotron. The dc coil encloses the ac magnetic circuit and thus links no ac flux. A shorted turn between the dc coil and ac flux enhances the separation of the two circuits. Several interesting developments are possible. The dc coil could be a stable superconductor to save power. The ac flux return gap could be identical with the synchrotron gap and contain a second synchrotron. This would double the output of the system. If the return flux gap were used for a booster, the ac coil power could be greatly reduced or radiation hardening of the ac coil could be simplified

  10. Irradiation device for electronic circuits

    International Nuclear Information System (INIS)

    The device includes a radiation-tight vessel, a mobile carriage for a radioactive source, a vertically mobile plate carrying a circuit to be tested and an irradiation detector. It includes also a cover related to the vacuum vessel which prevents the source from emitting for a certain source position. It includes also means which prevents irradiation when the vessel is not assembled and which prevents the dismantling when the source is radiating. It includes also a device allowing to disconnect the translation displacement controls of the circuit and of the radiation detector when the source is radiating

  11. Electronic circuits fundamentals and applications

    CERN Document Server

    Tooley, Mike

    2009-01-01

    The essential textbook for students following pre-degree level courses, technician engineers, and all who need to access a straightforwardly written reference covering all the major areas of 21st century electronics.Mike Tooley's classic reference texts Electronic Circuits Handbook and Electronics Circuits Students Handbook have long offered a unique coverage of analog and digital electronics and applications in a single volume. The two versions of this title have now been combined to produce a major textbook which combines comprehensive coverage of principles and applications with readability

  12. Short-circuit impedance measurement

    DEFF Research Database (Denmark)

    Pedersen, Knud Ole Helgesen; Nielsen, Arne Hejde; Poulsen, Niels Kjølstad

    2003-01-01

    Methods for estimating the short-circuit impedance in the power grid are investigated for various voltage levels and situations. The short-circuit impedance is measured, preferably from naturally occurring load changes in the grid, and it is shown that such a measurement system faces different...... kinds of problems at different locations in the grid. This means that the best measurement methodology changes depending on the location in the grid. Three typical examples with different measurement problems at 400 kV, 132 kV and 400 V voltage level are discussed....

  13. Embedded systems circuits and programming

    CERN Document Server

    Sanchez, Julio

    2012-01-01

    During the development of an engineered product, developers often need to create an embedded system--a prototype--that demonstrates the operation/function of the device and proves its viability. Offering practical tools for the development and prototyping phases, Embedded Systems Circuits and Programming provides a tutorial on microcontroller programming and the basics of embedded design. The book focuses on several development tools and resources: Standard and off-the-shelf components, such as input/output devices, integrated circuits, motors, and programmable microcontrollers The implementat

  14. Simplified design of filter circuits

    CERN Document Server

    Lenk, John

    1999-01-01

    Simplified Design of Filter Circuits, the eighth book in this popular series, is a step-by-step guide to designing filters using off-the-shelf ICs. The book starts with the basic operating principles of filters and common applications, then moves on to describe how to design circuits by using and modifying chips available on the market today. Lenk's emphasis is on practical, simplified approaches to solving design problems.Contains practical designs using off-the-shelf ICsStraightforward, no-nonsense approachHighly illustrated with manufacturer's data sheets

  15. Fermionic models with superconducting circuits

    Energy Technology Data Exchange (ETDEWEB)

    Las Heras, Urtzi; Garcia-Alvarez, Laura; Mezzacapo, Antonio; Lamata, Lucas [University of the Basque Country UPV/EHU, Department of Physical Chemistry, Bilbao (Spain); Solano, Enrique [University of the Basque Country UPV/EHU, Department of Physical Chemistry, Bilbao (Spain); IKERBASQUE, Basque Foundation for Science, Bilbao (Spain)

    2015-12-01

    We propose a method for the efficient quantum simulation of fermionic systems with superconducting circuits. It consists in the suitable use of Jordan-Wigner mapping, Trotter decomposition, and multiqubit gates, be with the use of a quantum bus or direct capacitive couplings. We apply our method to the paradigmatic cases of 1D and 2D Fermi-Hubbard models, involving couplings with nearest and next-nearest neighbours. Furthermore, we propose an optimal architecture for this model and discuss the benchmarking of the simulations in realistic circuit quantum electrodynamics setups. (orig.)

  16. Circuit, Thermal and Cost Characteristics of Impulse Magnetizing Circuits

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This paper describes the development of circuit, thermal and cost model for a capacitor discharge impulse megnetizer and compares simulations to measurements from an actual system. We used a cost structure consisting of five major subsystems for cost modeling. Especially, we estimated the potential for cost reductions impulse magnetizer as a function of time using the learning curve.

  17. Evaluating a scientific collaboratory

    DEFF Research Database (Denmark)

    Sonnenwald, Diane H.; Whitton, Mary C.; Maglaughlin, Kelly L.

    2003-01-01

    process of scientific work completed by 20 pairs of participants (upper level undergraduate science students) working face-to-face and remotely. We collected scientific outcomes (graded lab reports) to investigate the quality of scientific work, post-questionnaire data to measure the adoptability of the......The evaluation of scientific collaboratories has lagged behind their development. Do the capabilities afforded by collaboratories outweigh their disadvantages? To evaluate a scientific collaboratory system, we conducted a repeated-measures controlled experiment that compared the outcomes and...... of collaborating remotely. While the data analysis produced null results, considered as a whole, the analysis leads us to conclude there is positive potential for the development and adoption of scientific collaboratory systems....

  18. Scientific Journalism in Armenia

    Science.gov (United States)

    Farmanyan, S. V.; Mickaelian, A. M.

    2015-07-01

    In the present study, the problems of scientific journalism and activities of Armenian science journalists are presented. Scientific journalism in the world, forms of its activities, Armenian Astronomical Society (ArAS) press-releases and their subjects, ArAS website "Mass Media News" section, annual and monthly calendars of astronomical events, and "Astghagitak" online journal are described. Most interesting astronomical subjects involved in scientific journalism, reasons for non-satisfactory science outreach and possible solutions are discussed.

  19. Circuit quantum electrodynamics with a nonlinear resonator

    CERN Document Server

    Bertet, P; Boissonneault, M; Bolduc, A; Mallet, F; Doherty, A C; Blais, A; Vion, D; Esteve, D

    2011-01-01

    One of the most studied model systems in quantum optics is a two-level atom strongly coupled to a single mode of the electromagnetic field stored in a cavity, a research field named cavity quantum electrodynamics or CQED. CQED has recently received renewed attention due to its implementation with superconducting artificial atoms and coplanar resonators in the so-called circuit quantum electrodynamics (cQED) architecture. In cQED, the couplings can be much stronger than in CQED due to the design flexibility of superconducting circuits and to the enhanced field confinement in one-dimensional cavities. This enabled the realization of fundamental quantum physics and quantum information processing experiments with a degree of control comparable to that obtained in CQED. The purpose of this chapter is to investigate the situation where the resonator to which the atom is coupled is made nonlinear with a Kerr-type nonlinearity, causing its energy levels to be nonequidistant. The system is then described by a nonlinea...

  20. MOS Current Mode Logic Near Threshold Circuits

    Directory of Open Access Journals (Sweden)

    Alexander Shapiro

    2014-06-01

    Full Text Available Near threshold circuits (NTC are an attractive and promising technology that provides significant power savings with some delay penalty. The combination of NTC technology with MOS current mode logic (MCML is examined in this work. By combining MCML with NTC, the constant power consumption of MCML is reduced to leakage power levels that can be tolerated in certain modern applications. Additionally, the speed of NTC is improved due to the high speed nature of MCML technology. A 14 nm Fin field effect transistor (FinFET technology is used to evaluate these combined circuit techniques. A 32-bit Kogge Stone adder is chosen as a demonstration vehicle for feasibility analysis. MCML with NTC is shown to yield enhanced power efficiency when operated above 1 GHz with a 100% activity factor as compared to standard CMOS. MCML with NTC is more power efficient than standard CMOS beyond 9 GHz over a wide range of activity factors. MCML with NTC also exhibits significantly lower noise levels as compared to standard CMOS. The results of the analysis demonstrate that pairing NTC and MCML is efficient when operating at high frequencies and activity factors.

  1. An Approach to Simplify Reversible Logic Circuits

    Directory of Open Access Journals (Sweden)

    Pabitra Roy

    2012-09-01

    Full Text Available Energy loss is one of the major problems in traditional irreversible circuits. For every bit of information loss kTln2 joules of heat is lost. In order to reduce the energy loss the concept of reversible logic circuits are introduced. Here we have described an algorithm for simplifying the reversible logic circuit and hence reduction of circuit cost and energy. The algorithm considers sub_circuit with respect to their number of lines and contiguous gates. The resulting sub_circuits are re-synthesized with smaller equivalent implementation. The process continues until circuit cost reaches good enough for Application or until a given computation budget has been exhausted. The circuit is constructed by NOT, CNOT and Toffoli gates only. By applying the algorithm and using the equivalent implementation we will get significant reduction of circuit cost and hence energy.

  2. Relaxation Based Electrical Simulation for VLSI Circuits

    Directory of Open Access Journals (Sweden)

    S. Rajkumar

    2012-06-01

    Full Text Available Electrical circuit simulation was one of the first CAD tools developed for IC design. The conventional circuit simulators like SPICE and ASTAP were designed initially for the cost effective analysis of circuits containing a few hundred transistors or less. A number of approaches have been used to improve the performances of congenital circuit simulators for the analysis of large circuits. Thereafter relaxation methods was proposed to provide more accurate waveforms than standard circuit simulators with up to two orders of magnitude speed improvement for large circuits. In this paper we have tried to highlights recently used waveform and point relaxation techniques for simulation of VLSI circuits. We also propose a simple parallelization technique and experimentally demonstrate that we can solve digital circuits with tens of million transistors in a few hours.

  3. The economic scientific research, a production neo-factor

    Directory of Open Access Journals (Sweden)

    Elena Ciucur

    2007-12-01

    Full Text Available The scientific research represents a modern production neo-factor that implies two groups of coordinates: preparation and scientific research. The scientific research represents a complex of elements that confer a new orientation of high performance and is materialized in resources and new availabilities brought in active shape by the contribution of the creators and by the attraction in a specific way in the economic circuit. It is the creator of new ideas, lifting the performance and understanding to the highest international standards of competitive economic efficiency. In the present, the role of the scientific research stands before some new challenges generated by the stage of society. It.s propose a unitary, coherent scientific research and educational system, created in corresponding proportions, based on the type, level and utility of the system, by the state, the economic-social environment and the citizen himself.

  4. Circuit design for RF transceivers

    CERN Document Server

    Leenaerts, Domine; Vaucher, Cicero S

    2007-01-01

    Second edition of this successful 2001 RF Circuit Design book, has been updated, latest technology reviews have been added as well as several actual case studies. Due to the authors being active in industry as well as academia, this should prove to be an essential guide on RF Transceiver Design for students and engineers.

  5. MOS integrated circuit fault modeling

    Science.gov (United States)

    Sievers, M.

    1985-01-01

    Three digital simulation techniques for MOS integrated circuit faults were examined. These techniques embody a hierarchy of complexity bracketing the range of simulation levels. The digital approaches are: transistor-level, connector-switch-attenuator level, and gate level. The advantages and disadvantages are discussed. Failure characteristics are also described.

  6. Unbalanced Neuronal Circuits in Addiction

    OpenAIRE

    Volkow, Nora D; Wang, Gen-Jack; Tomasi, Dardo; Baler, Ruben D.

    2013-01-01

    Through sequential waves of drug-induced neurochemical stimulation, addiction co-opts the brain's neuronal circuits that mediate reward, motivation, , to behavioral inflexibility and a severe disruption of self-control and compulsive drug intake. Brain imaging technologies have allowed neuroscientists to map out the neural landscape of addiction in the human brain and to understand how drugs modify it.

  7. Testing Superconductor Logic Integrated Circuits

    OpenAIRE

    Joseph, Arun A.; Kerkhoff, Hans G.

    2005-01-01

    Superconductor logic has the potential of extremely low-power consumption and ultra-fast digital signal processing. Unfortunately, the obtained yield of the present processes is low and specific faults occur. This paper deals with fault-modelling, Design-for-Test structures, and ATPG for these integrated circuits.

  8. Integrated Circuit Stellar Magnitude Simulator

    Science.gov (United States)

    Blackburn, James A.

    1978-01-01

    Describes an electronic circuit which can be used to demonstrate the stellar magnitude scale. Six rectangular light-emitting diodes with independently adjustable duty cycles represent stars of magnitudes 1 through 6. Experimentally verifies the logarithmic response of the eye. (Author/GA)

  9. Low-frequency attenuator circuit

    Science.gov (United States)

    Cash, W. H., Jr.; Polyhemus, J. T.

    1979-01-01

    Circuit uses only single operational amplifier and few passive components to remove background noise from miniature "wristwatch" pulse detector. It can be applied to other systems where background noise is slowly varying, such as ultrasonics, strain-gage sensors, and accelerometers.

  10. Single Event Transients in Linear Integrated Circuits

    Science.gov (United States)

    Buchner, Stephen; McMorrow, Dale

    2005-01-01

    to transients. In some cases, such events produced resets by falsely triggering circuits designed to protect against over- voltage or over-current. On at least three occasions, transients caused satellites to switch into "safe mode" in which most of the systems on board the satellites were powered down for an extended period. By the time the satellites were reconfigured and returned to full operational state, much scientific data had been lost. Fortunately, no permanent damage occurred in any of the systems and they were all successfully re-activated.

  11. Timing control by redundant inhibitory neuronal circuits

    Energy Technology Data Exchange (ETDEWEB)

    Tristan, I., E-mail: itristan@ucsd.edu; Rulkov, N. F.; Huerta, R.; Rabinovich, M. [BioCircuits Institute, University of California, San Diego, La Jolla, California 92093-0402 (United States)

    2014-03-15

    Rhythms and timing control of sequential activity in the brain is fundamental to cognition and behavior. Although experimental and theoretical studies support the understanding that neuronal circuits are intrinsically capable of generating different time intervals, the dynamical origin of the phenomenon of functionally dependent timing control is still unclear. Here, we consider a new mechanism that is related to the multi-neuronal cooperative dynamics in inhibitory brain motifs consisting of a few clusters. It is shown that redundancy and diversity of neurons within each cluster enhances the sensitivity of the timing control with the level of neuronal excitation of the whole network. The generality of the mechanism is shown to work on two different neuronal models: a conductance-based model and a map-based model.

  12. Separating OR, SUM, and XOR Circuits

    OpenAIRE

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

    2013-01-01

    Given a boolean n by 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 \\emph{separating} these models in terms of their circuit complexities. We give three results towards this goal: (1) We prove a direct sum type theorem on the monotone complexity of ...

  13. Advanced circuit simulation using Multisim workbench

    CERN Document Server

    Báez-López, David; Cervantes-Villagómez, Ofelia Delfina

    2012-01-01

    Multisim is now the de facto standard for circuit simulation. It is a SPICE-based circuit simulator which combines analog, discrete-time, and mixed-mode circuits. In addition, it is the only simulator which incorporates microcontroller simulation in the same environment. It also includes a tool for printed circuit board design.Advanced Circuit Simulation Using Multisim Workbench is a companion book to Circuit Analysis Using Multisim, published by Morgan & Claypool in 2011. This new book covers advanced analyses and the creation of models and subcircuits. It also includes coverage of transmissi

  14. Digital circuit boards mach 1 GHz

    CERN Document Server

    Morrison, Ralph

    2012-01-01

    A unique, practical approach to the design of high-speed digital circuit boards The demand for ever-faster digital circuit designs is beginning to render the circuit theory used by engineers ineffective. Digital Circuit Boards presents an alternative to the circuit theory approach, emphasizing energy flow rather than just signal interconnection to explain logic circuit behavior. The book shows how treating design in terms of transmission lines will ensure that the logic will function, addressing both storage and movement of electrical energy on these lines. It cove

  15. Fast Equivalence-checking for Quantum Circuits

    CERN Document Server

    Yamashita, Shigeru

    2009-01-01

    We perform formal verification of quantum circuits by integrating several techniques specialized to particular classes of circuits. Our verification methodology is based on the new notion of a reversible miter that allows one to leverage existing techniques for circuit simplification of quantum circuits. For reversible circuits which arise as runtime bottlenecks of key quantum algorithms, we develop several verification techniques and empirically compare them. We also combine existing quantum verification tools with the use of SAT-solvers. Experiments with circuits for Shor's number-factoring algorithm, containing thousands of gates, show improvements in efficiency by four orders of magnitude.

  16. A hierarchical approach to test generation for CMOS VLSI circuits

    Science.gov (United States)

    Weening, Edward Christiaan

    A hierarchical approach to the automatic test pattern generation for large digital VLSI circuits, fabricated in CMOS technology, is developed and implemented. The use of information on the circuit's hierarchy, which is readily available from most modern CAD (Computer Aided Design) systems, speeds up the test generation process considerably and enhances the quality of the tests generated. The hierarchical test generation tool can also be integrated in future CAD systems making test generation and testability enhancement during circuit design feasible. The hierarchical approach is described at the switch, functional, and behavioral level. A test pattern generation algorithm at the switch level is presented. Test generation and fault simulation algorithms both using OBDD (Ordered Binary Decision Diagram) functional descriptions of the circuit modules are presented. A test plan generation method at the behavioral level is presented. Practical results show that the hierarchical approach to test generation is more efficient than a conventional, non-hierarchical approach, especially for switch level faults. The results also show that the use of Design For Testability (DFT) circuitry is supported at the behavioral level.

  17. Scientific rigor through videogames.

    Science.gov (United States)

    Treuille, Adrien; Das, Rhiju

    2014-11-01

    Hypothesis-driven experimentation - the scientific method - can be subverted by fraud, irreproducibility, and lack of rigorous predictive tests. A robust solution to these problems may be the 'massive open laboratory' model, recently embodied in the internet-scale videogame EteRNA. Deploying similar platforms throughout biology could enforce the scientific method more broadly. PMID:25300714

  18. Mobile Scientific Calculator

    Directory of Open Access Journals (Sweden)

    Mohammed Abdulrahim Hamdi

    2012-02-01

    Full Text Available The mobile and wireless industry is entering an exciting time. Demand for mobile technology is growing at a tremendous rate. Corporations are deploying mobile applications that provide substantial business benefits, and consumers are readily adopting mobile data applications. We present scientific application for mobile phone in steps of software engineering project starting from data gathering, data analysis, designing, coding, packaging, testing and deploying, Mobile Scientific Calculator (MSC enable user to compute any mathematical operation by using this application in mobile phone without needing to use the calculator. Scientific calculator offers three keys the four mathematic operations, the four systems of digits and offering many of functions such as angles functions, power, factorial and other functions. Scientific calculator is suitable for many mobile phones which don t have scientific calculator in its applications, it provide simple design for dealing with its functions for all users. It operated on more than one mobile phone model.

  19. Strengthening Construction of Scientific Research Platform to Enhance the Ability of Scientific and Technological Innovation, Taking Harbin Veterinary Research Institute of CAAS as a Case%加强科研平台建设提升科技创新能力——以中国农业科学院哈尔滨兽医研究所为例

    Institute of Scientific and Technical Information of China (English)

    张艳禾; 刘爽; 刘益民

    2016-01-01

    Scientific research innovation platform is an important carrier to improve the innovative and practical ability of scientific research personnel, improve the level of scientific research institutions. Strengthening the construction of scientific and technological innovation platform and improving the scientific and technological innovation ability are of great significance for the promotion of sustainable development of research institutes. Taking the Harbin Veterinary Research Institute of Chinese Academy of Agricultural Sciences as an example, the significance and function of scientific research platform construction were expounded in the paper. Effect and the existing problems of utilizing scientific platform to boost the innovative ability of researchers were analyzed. Measures for improving management level of these platforms were put forward, i.e., innovating managing mechanism and raising the managing and operating level, strengthening construction of evaluation system and improving scientific evaluating modes, paying attention to building of team and motivating innovative vigor. These supplied references for the construction and management of scientific and technological condition platform in our country.%科研创新平台是提高科研人员创新和实践能力、提升科研机构创新水平的重要载体,强化科研创新平台建设,提高科技创新能力对于促进研究所可持续性发展意义重大.文章以中国农业科学院哈尔滨兽医研究所为例,阐述了科研平台建设的意义和作用,分析了利用科研平台提高科研人员创新能力的效果及目前存在的问题,提出了创新管理机制,提高管理运行水平;强化评价体系建设,完善科学评价方式;注重人才团队建设,激发创新活力等提升科研平台管理水平的措施,以期为加强我国农业科技条件平台建设与管理提供借鉴.

  20. Scientific Utopia: I. Opening scientific communication

    CERN Document Server

    Nosek, Brian A

    2012-01-01

    Existing norms for scientific communication are rooted in anachronistic practices of bygone eras, making them needlessly inefficient. We outline a path that moves away from the existing model of scientific communication to improve the efficiency in meeting the purpose of public science - knowledge accumulation. We call for six changes: (1) full embrace of digital communication, (2) open access to all published research, (3) disentangling publication from evaluation, (4) breaking the "one article, one journal" model with a grading system for evaluation and diversified dissemination outlets, (5) publishing peer review, and, (6) allowing open, continuous peer review. We address conceptual and practical barriers to change, and provide examples showing how the suggested practices are being used already. The critical barriers to change are not technical or financial; they are social. While scientists guard the status quo, they also have the power to change it.

  1. The voltage-current relationship and equivalent circuit implementation of parallel flux-controlled memristive circuits

    Institute of Scientific and Technical Information of China (English)

    Bao Bo-Cheng; Feng Fei; Dong Wei; Pan Sai-Hu

    2013-01-01

    A flux-controlled memristor characterized by smooth cubic nonlinearity is taken as an example,upon which the voltage-current relationships (VCRs) between two parallel memristive circuits-a parallel memristor and capacitor circuit (the parallel MC circuit),and a parallel memristor and inductor circuit (the parallel ML circuit)-are investigated.The results indicate that the VCR between these two parallel memristive circuits is closely related to the circuit parameters,and the frequency and amplitude of the sinusoidal voltage stimulus.An equivalent circuit model of the memristor is built,upon which the circuit simulations and experimental measurements of both the parallel MC circuit and the parallel ML circuit are performed,and the results verify the theoretical analysis results.

  2. Analog Nonvolatile Computer Memory Circuits

    Science.gov (United States)

    MacLeod, Todd

    2007-01-01

    In nonvolatile random-access memory (RAM) circuits of a proposed type, digital data would be stored in analog form in ferroelectric field-effect transistors (FFETs). This type of memory circuit would offer advantages over prior volatile and nonvolatile types: In a conventional complementary metal oxide/semiconductor static RAM, six transistors must be used to store one bit, and storage is volatile in that data are lost when power is turned off. In a conventional dynamic RAM, three transistors must be used to store one bit, and the stored bit must be refreshed every few milliseconds. In contrast, in a RAM according to the proposal, data would be retained when power was turned off, each memory cell would contain only two FFETs, and the cell could store multiple bits (the exact number of bits depending on the specific design). Conventional flash memory circuits afford nonvolatile storage, but they operate at reading and writing times of the order of thousands of conventional computer memory reading and writing times and, hence, are suitable for use only as off-line storage devices. In addition, flash memories cease to function after limited numbers of writing cycles. The proposed memory circuits would not be subject to either of these limitations. Prior developmental nonvolatile ferroelectric memories are limited to one bit per cell, whereas, as stated above, the proposed memories would not be so limited. The design of a memory circuit according to the proposal must reflect the fact that FFET storage is only partly nonvolatile, in that the signal stored in an FFET decays gradually over time. (Retention times of some advanced FFETs exceed ten years.) Instead of storing a single bit of data as either a positively or negatively saturated state in a ferroelectric device, each memory cell according to the proposal would store two values. The two FFETs in each cell would be denoted the storage FFET and the control FFET. The storage FFET would store an analog signal value

  3. Changing Views of Basal Ganglia Circuits and Circuit Disorders

    OpenAIRE

    DeLong, Mahlon; Wichmann, Thomas

    2010-01-01

    The basal ganglia (BG) have long been considered to play an important role in the control of movement and the pathophysiology of movement disorders, such as Parkinson’s disease (PD). Studies over the past decades have considerably broadened this view, indicating that the BG participate in multiple, parallel, largely segregated, cortico-subcortical reentrant pathways involving motor, associative and limbic functions. Research has shown that dysfunction within individual circuits is associated ...

  4. Insulin-like growth factor 1 (IGF1) and its active peptide (1-3)IGF1 enhance the expression of synaptic markers in neuronal circuits through different cellular mechanisms.

    LENUS (Irish Health Repository)

    Corvin, Aiden P

    2012-06-27

    Insulin-like growth factor-1 (IGF1) and its active peptide (1-3)IGF1 modulate brain growth and plasticity and are candidate molecules for treatment of brain disorders. IGF1 N-terminal portion is naturally cleaved to generate the tri-peptide (1-3)IGF1 (glycine-praline-glutamate). IGF1 and (1-3)IGF have been proposed as treatment for neuropathologies, yet their effect on nerve cells has not been directly compared. In this study we examine the effects of IGF1 and (1-3)IGF1 in primary cortical cultures and measure the expression levels of markers for intracellular pathways and synaptic function. We find that both treatments activate the IGF1 receptor and enhance the expression of synaptic markers, however, they activate different intracellular pathways. Furthermore, (1-3)IGF1 administration increases the expression of endogenous IGF1, suggesting a direct interaction between the two molecules. The results show that the two molecules increase the expression of synaptic proteins through activating different cellular mechanisms.

  5. Plug-in integrated/hybrid circuit

    Science.gov (United States)

    Stringer, E. J.

    1974-01-01

    Hybrid circuitry can be installed into standard round bayonet connectors, to eliminate wiring from connector to circuit. Circuits can be connected directly into either section of connector pair, eliminating need for hard wiring to that section.

  6. Driver circuit for solid state light sources

    Science.gov (United States)

    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.

  7. Grand Research Plan for Neural Circuits of Emotion and Memory-Current status of neural circuit studies in China

    Institute of Scientific and Technical Information of China (English)

    Yuan-Gui Zhu; He-Qi Cao; Er-Dan Dong

    2013-01-01

    During recent years,major advances have been made in neuroscience,i.e.,asynchronous release,three-dimensional structural data sets,saliency maps,magnesium in brain research,and new functional roles of long non-coding RNAs.Especially,the development of optogenetic technology provides access to important information about relevant neural circuits by allowing the activation of specific neurons in awake mammals and directly observing the resulting behavior.The Grand Research Plan for Neural Circuits of Emotion and Memory was launched by the National Natural Science Foundation of China.It takes emotion and memory as its main objects,making the best use of cutting-edge technologies from medical science,life science and information science.In this paper,we outline the current status of neural circuit studies in China and the technologies and methodologies being applied,as well as studies related to the impairments of emotion and memory.In this phase,we are making efforts to repair the current deficiencies by making adjustments,mainly involving four aspects of core scientific issues to investigate these circuits at multiple levels.Five research directions have been taken to solve important scientific problems while the Grand Research Plan is implemented.Future research into this area will be multimodal,incorporating a range of methods and sciences into each project.Addressing these issues will ensure a bright future,major discoveries,and a higher level of treatment for all affected by debilitating brain illnesses.

  8. Black hole qubit correspondence from quantum circuits

    CERN Document Server

    Prudencio, Thiago; Silva, Edilberto O; Belich, Humberto

    2014-01-01

    We propose a black hole qubit correspondence (BHQC) from quantum circuits, taking into account the BHQC formulations of wrapped brane qubits. With base on BHQC, we implement the corresponding gate operations to realize any given quantum circuit. In particular, we implement cases of the generation of Bell states, quantum teleportation and GHZ states circuits. Finally, we give an interpretation of the BHQC from quantum circuits with base on the BHQC classification of entanglement classes.

  9. Brain-machine interface circuits and systems

    CERN Document Server

    Zjajo, Amir

    2016-01-01

    This book provides a complete overview of significant design challenges in respect to circuit miniaturization and power reduction of the neural recording system, along with circuit topologies, architecture trends, and (post-silicon) circuit optimization algorithms. The introduced novel circuits for signal conditioning, quantization, and classification, as well as system configurations focus on optimized power-per-area performance, from the spatial resolution (i.e. number of channels), feasible wireless data bandwidth and information quality to the delivered power of implantable system.

  10. Solid-State dc Circuit Breaker

    Science.gov (United States)

    Harvey, P.

    1983-01-01

    Circuit breaker with no moving parts protects direct-current (dc) loads. Current which circuit breaker opens (trip current) is adjustable and so is time delay before breaker trips. Forward voltage drop rises from 0.6 to 1.2 V as current rises to trip point. Breaker has two terminals, like fuse, therefore replaces fuse in dc circuit. Powered by circuit it protects and reset by either turning off power source or disconnecting load.

  11. What's new about generator circuit breakers

    International Nuclear Information System (INIS)

    The need for updating ANSI C37 Standards for AC high-voltage circuit breakers has become necessary because of the increased interest in power circuit breakers for generator application. These circuit breakers, which have continuous current ratings and rated short-circuit currents that are much higher than those presently covered by existing C37 Standards, take on added importance because they are being installed in critical AC power supplies at nuclear power stations

  12. Trip electrical circuit of the gyrotion

    International Nuclear Information System (INIS)

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

  13. An Overview of Defected Ground Structure with Practical Application of Defected Ground Structure Bandpass Filter in Energy Harvester Circuit

    OpenAIRE

    Khan, M. T.; M.A. Zakariya; Z. Baharudin; R. Ibrahim; S.S.B. Hong; J.J. Adz

    2014-01-01

    The aim of the study is to practically implement the Defected Ground Structure (DGS) based microstrip bandpass filter in an energy harvester circuit. DGS is widely used to bring about an enhancement in the characteristics of microwave circuits. The study of DGS is derived from the concept of Photonic/electromagnetic Band Gap (PBG) structures but it is easier to design and fabricate and has an easier equivalent LC resonator circuit. In this study, DGS has been reviewed from all aspects such as...

  14. Preperation of Scientific Movies

    Directory of Open Access Journals (Sweden)

    Bülent Pekdağ

    2007-12-01

    Full Text Available This study aims to provide information on the preparation of the scientific movies as a part of Information and Communications Technology. The preparation stages of the scientific movies and their visualizations on computer screens were described. For preparing movies, the unit on the "acid-base reactions" on 11th grade French chemistry curriculum was used, and the knowledge presented in the movies was determined by an analysis of the 11th grade chemistry curriculum and the chemistry books. Also, the information that will be beneficial for readers and researchers on the scenario preparation of scientific movies and picture selection was mentioned.

  15. A cortical circuit for gain control by behavioral state

    OpenAIRE

    Fu, Yu; Tucciarone, Jason M.; Espinosa, J. Sebastian; Sheng, Nengyin; Darcy, Daniel P.; Nicoll, Roger A.; Huang, Z. Josh; Stryker, Michael P

    2014-01-01

    The brain’s response to sensory input is strikingly modulated by behavioral state. Notably, the visual response of mouse primary visual cortex (V1) is enhanced by locomotion, a tractable and accessible example of a time-locked change in cortical state. The neural circuits that transmit behavioral state to sensory cortex to produce this modulation are unknown. In vivo calcium imaging of behaving animals revealed that locomotion activates vasoactive intestinal peptide (VIP)-positive neurons in ...

  16. MAPK transgenic circuit to improve plant stress-tolerance?

    OpenAIRE

    Moustafa, Khaled

    2014-01-01

    Thanks to their distinctive mode of action in a coordinated switch-like way, their multi-tiered signaling cascades and their involvement in cell responses to multiple internal and external stimuli, MAP kinases offer a remarkable possibility to be assembled into what we can call “MAPK transgenic circuits” to improve cell functions. Such circuit could be used to enhance cell signaling efficiency and boost cell functions for several purposes in plant biotechnology, medicine, and pharmaceutical i...

  17. MAPK transgenic circuit to improve plant stress-tolerance?

    Science.gov (United States)

    Moustafa, Khaled

    2014-01-01

    Thanks to their distinctive mode of action in a coordinated switch-like way, their multi-tiered signaling cascades and their involvement in cell responses to multiple internal and external stimuli, MAP kinases offer a remarkable possibility to be assembled into what we can call “MAPK transgenic circuits” to improve cell functions. Such circuit could be used to enhance cell signaling efficiency and boost cell functions for several purposes in plant biotechnology, medicine, and pharmaceutical industry. PMID:25482799

  18. Initialization by Measurement of a Superconducting Quantum Bit Circuit

    OpenAIRE

    Riste, D.; van Leeuwen, J. G.; Ku, H.S.; Lehnert, K. W.; DiCarlo, L.

    2012-01-01

    We demonstrate initialization by joint measurement of two transmon qubits in 3D circuit quantum electrodynamics. Homodyne detection of cavity transmission is enhanced by Josephson parametric amplification to discriminate the two-qubit ground state from single-qubit excitations nondestructively and with 98.1% fidelity. Measurement and postselection of a steady-state mixture with 4.7% residual excitation per qubit achieve 98.8% fidelity to the ground state, thus outperforming passive initializa...

  19. 49 CFR 236.731 - Controller, circuit.

    Science.gov (United States)

    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....

  20. A Current-mode Logarithmic Function Circuit

    OpenAIRE

    Osama Oglah Faris; Muhammad Taher Abuelma'atti

    2004-01-01

    A new current-mode analog circuit configuration that implements the function ln (x/y) is proposed. The circuit uses bipolar transistors and resistors and is suitable for integration. In the proposed circuit the ratio (x/y) can be larger or smaller than unity. Simulation results are included.

  1. 47 CFR 32.2232 - Circuit equipment.

    Science.gov (United States)

    2010-10-01

    ... 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... which is used for the amplification, modulation, regeneration, circuit patching, balancing or control...

  2. 49 CFR 236.726 - Circuit, track.

    Science.gov (United States)

    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....

  3. 49 CFR 236.721 - Circuit, control.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, control. 236.721 Section 236.721 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, control. An electrical circuit between a source of electric energy and a device which it operates....

  4. 30 CFR 56.6407 - Circuit testing.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Circuit testing. 56.6407 Section 56.6407... Blasting § 56.6407 Circuit testing. A blasting galvanometer or other instrument designed for testing blasting circuits shall be used to test each of the following: (a) Continuity of each electric detonator...

  5. An eigenvalue study of the MLC circuit

    DEFF Research Database (Denmark)

    Lindberg, Erik; Murali, K.

    1998-01-01

    The MLC (Murali-Lakshmanan-Chua) circuit is the simplest non-autonomous chaotic circuit. Insight in the behaviour of the circuit is obtained by means of a study of the eigenvalues of the linearized Jacobian of the nonlinear differential equations. The trajectories of the eigenvalues as functions of...

  6. 30 CFR 57.6407 - Circuit testing.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Circuit testing. 57.6407 Section 57.6407... Blasting-Surface and Underground § 57.6407 Circuit testing. A blasting galvanometer or other instrument designed for testing blasting circuits shall be used to test the following: (a) In surface operations—...

  7. The dc power circuits: A compilation

    Science.gov (United States)

    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.

  8. An Equivalent Circuit for Landau Damping

    DEFF Research Database (Denmark)

    Pécseli, Hans

    1976-01-01

    An equivalent circuit simulating the effect of Landau damping in a stable plasma‐loaded parallel‐plate capacitor is presented. The circuit contains a double infinity of LC components. The transition from stable to unstable plasmas is simulated by the introduction of active elements into the circuit....

  9. 30 CFR 75.1323 - Blasting circuits.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Blasting circuits. 75.1323 Section 75.1323... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1323 Blasting circuits. (a) Blasting circuits shall be protected from sources of stray electric current. (b) Detonators made...

  10. Trends in Scientific Publishing at Springer

    Science.gov (United States)

    Eichhorn, Guenther

    Scientific publishing has undergone tremendous changes in the last decade, and it is still evolving rapidly. This article describes some of the issues that are facing scientific publishers, and shows some examples of what one of the commercial publishers, Springer, has done and is working on, in order to stay abreast of these changes and to embrace the new technologies that become available. Springer has moved rapidly into the digital age and has by now digitized almost all its journal content and a significant part of its book content. We have developed new capabilities that make use of the new technologies available and are in the process of further utilizing these new possibilities. Web products like AuthorMapper, SpringerProtocols, and Social Networking sites explore some of these new capabilities. We will continue to explore enhancements of our scientific publishing efforts to provide new possibilities for communicating scientific research.

  11. Ionization tube simmer current circuit

    Science.gov (United States)

    Steinkraus, Jr., Robert F.

    1994-01-01

    A highly efficient flash lamp simmer current circuit utilizes a fifty percent duty cycle square wave pulse generator to pass a current over a current limiting inductor to a full wave rectifier. The DC output of the rectifier is then passed over a voltage smoothing capacitor through a reverse current blocking diode to a flash lamp tube to sustain ionization in the tube between discharges via a small simmer current. An alternate embodiment of the circuit combines the pulse generator and inductor in the form of an FET off line square wave generator with an impedance limited step up output transformer which is then applied to the full wave rectifier as before to yield a similar simmer current.

  12. Delay locked loop integrated circuit.

    Energy Technology Data Exchange (ETDEWEB)

    Brocato, Robert Wesley

    2007-10-01

    This report gives a description of the development of a Delay Locked Loop (DLL) integrated circuit (IC). The DLL was developed and tested as a stand-alone IC test chip to be integrated into a larger application specific integrated circuit (ASIC), the Quadrature Digital Waveform Synthesizer (QDWS). The purpose of the DLL is to provide a digitally programmable delay to enable synchronization between an internal system clock and external peripherals with unknown clock skew. The DLL was designed and fabricated in the IBM 8RF process, a 0.13 {micro}m CMOS process. It was designed to operate with a 300MHz clock and has been tested up to 500MHz.

  13. Integrated circuits for multimedia applications

    DEFF Research Database (Denmark)

    Vandi, Luca

    2007-01-01

    This work presents several key aspects in the design of RF integrated circuits for portable multimedia devices. One chapter is dedicated to the application of negative-feedback topologies to receiver frontends. A novel feedback technique suitable for common multiplier-based mixers is described, and...... it is applied to a broad-band dual-loop receiver architecture in order to boost the linearity performances of the stage. A simplified noise- and linearity analysis of the circuit is derived, and a comparison is provided with a more traditional dual-loop topology (a broad-band stage based on shunt...... for the performances of the stage. Semi-ideal models are used in simulations to validate the derived calculations, and the fundamental limits of the basic structure are discussed. The design of a current-mode base-band output stage implemented in a 0.13um technology is presented: the amplifier draws...

  14. Planar Multilayer Circuit Quantum Electrodynamics

    Science.gov (United States)

    Minev, Z. K.; Serniak, K.; Pop, I. M.; Leghtas, Z.; Sliwa, K.; Hatridge, M.; Frunzio, L.; Schoelkopf, R. J.; Devoret, M. H.

    2016-04-01

    Experimental quantum information processing with superconducting circuits is rapidly advancing, driven by innovation in two classes of devices, one involving planar microfabricated (2D) resonators, and the other involving machined three-dimensional (3D) cavities. We demonstrate that circuit quantum electrodynamics can be implemented in a multilayer superconducting structure that combines 2D and 3D advantages. We employ standard microfabrication techniques to pattern each layer, and rely on a vacuum gap between the layers to store the electromagnetic energy. Planar qubits are lithographically defined as an aperture in a conducting boundary of the resonators. We demonstrate the aperture concept by implementing an integrated, two-cavity-mode, one-transmon-qubit system.

  15. Monolithic readout circuits for RHIC

    International Nuclear Information System (INIS)

    Several CMOS ASICs have been developed for a proposed RHIC experiment. This paper discusses why ASIC implementation was chosen for certain functions, circuit specifications and the design techniques used to meet them, and results of simulations and early prototypes. By working closely together from an early stage in the planning process, in-house ASIC designers and detector and data acquisition experimenters can achieve optimal use of this important technology

  16. Synthetic circuits, devices and modules

    OpenAIRE

    Zhang, Hong; Jiang, Taijiao

    2010-01-01

    The aim of synthetic biology is to design artificial biological systems for novel applications. From an engineering perspective, construction of biological systems of defined functionality in a hierarchical way is fundamental to this emerging field. Here, we highlight some current advances on design of several basic building blocks in synthetic biology including the artificial gene control elements, synthetic circuits and their assemblies into devices and modules. Such engineered basic buildi...

  17. ?Immunetworks?, intersecting circuits and dynamics

    OpenAIRE

    Demongeot, Jacques; Elena, Adrien; Noual, Mathilde; Sené, Sylvain; Thuderoz, Florence

    2011-01-01

    Abstract This paper proposes a study of biological regulatory networks based on a multi-level strategy. Given a network, the first structural level of this strategy consists in analysing the architecture of the network interactions in order to describe it. The second dynamical level consists in relating the patterns found in the architecture to the possible dynamical behaviours of the network. It is known that circuits are the patterns that play the most important part in the dynam...

  18. Parallelism through Digital Circuit Design

    OpenAIRE

    O'Donnell, John

    2008-01-01

    Two ways to exploit chips with a very large number of transistors are multicore processors and programmable logic chips. Some data parallel algorithms can be executed efficiently on ordinary parallel computers, including multicores. A class of data parallel algorithms is identified which have characteristics that make implementation on multiprocessors inefficient, but they are well suited for direct design as digital circuits. This leads to a programming model called c...

  19. Equivalent circuit analysis of sled

    International Nuclear Information System (INIS)

    A direct application of equivalent circuit concepts leads to: (1) confirmation of Perry Wilson's SLED (SLAC Linac Energy Doubler) equation; (2) an equation that applies to a SLED device with input and output waveguides of different characteristic impedances; and (3) an equation that results if we demand that no power be lost by reflection from SLED. If the incident voltage is tailored as prescribed by this equation, the cavity voltage tracks the incident voltage and the reflected voltage is zero

  20. An Interpreter for Quantum Circuits

    OpenAIRE

    Lucas Helms; Ruben Gamboa

    2013-01-01

    This paper describes an ACL2 interpreter for "netlists" describing quantum circuits. Several quantum gates are implemented, including the Hadamard gate H, which rotates vectors by 45 degrees, necessitating the use of irrational numbers, at least at the logical level. Quantum measurement presents an especially difficult challenge, because it requires precise comparisons of irrational numbers and the use of random numbers. This paper does not address computation with irrational numbers or the g...

  1. Monolithic readout circuits for RHIC

    Energy Technology Data Exchange (ETDEWEB)

    O`Connor, P.; Harder, J. [Brookhaven National Laboratory, Upton, NY (United States)

    1991-12-31

    Several CMOS ASICs have been developed for a proposed RHIC experiment. This paper discusses why ASIC implementation was chosen for certain functions, circuit specifications and the design techniques used to meet them, and results of simulations and early prototypes. By working closely together from an early stage in the planning process, in-house ASIC designers and detector and data acquisition experimenters can achieve optimal use of this important technology.

  2. Root finding with threshold circuits

    Czech Academy of Sciences Publication Activity Database

    Jeřábek, Emil

    2012-01-01

    Roč. 462, Nov 30 (2012), s. 59-69. ISSN 0304-3975 R&D Projects: GA AV ČR IAA100190902; GA MŠk(CZ) 1M0545 Institutional support: RVO:67985840 Keywords : root finding * threshold circuit * power series Subject RIV: BA - General Mathematics Impact factor: 0.489, year: 2012 http://www.sciencedirect.com/science/article/pii/S0304397512008006#

  3. Chemistry of the secondary circuit

    International Nuclear Information System (INIS)

    Study of the various possibilities to prevent the corrosion phenomena in the different parts of the secondary circuit (condenser, water facility, steam lines, turbines and vapor generators): choice of a volatile conditioning with ammonia or morpholine and not with phosphate which concentration in the vapor generators may induce local corrosion, and search for a low oxidizing medium by restriction of the air admission and addition of hydrazine

  4. Chaos in circuits and systems

    CERN Document Server

    Chen, Guanrong

    2002-01-01

    In this volume, leading experts present current achievements in the forefront of research in the challenging field of chaos in circuits and systems, with emphasis on engineering perspectives, methodologies, circuitry design techniques, and potential applications of chaos and bifurcation. A combination of overview, tutorial and technical articles, the book describes state-of-the-art research on significant problems in this field. It is suitable for readers ranging from graduate students, university professors, laboratory researchers and industrial practitioners to applied mathematicians and phy

  5. Microcontroller based Integrated Circuit Tester

    OpenAIRE

    Yousif Taha Yousif Elamin; Abdelrasoul Jabar Alzubaidi

    2015-01-01

    The digital integrated circuit (IC) tester is implemented by using the ATmega32 microcontroller . The microcontroller processes the inputs and outputs and displays the results on a Liquid Crystal Display (LCD). The basic function of the digital IC tester is to test a digital IC for correct logical functioning as described in the truth table and/or function table. The designed model can test digital ICs having 14 pins. Since it is programmable, any number of ICs can be tested . Thi...

  6. Circuit analysis of quantum measurement

    OpenAIRE

    Kurotani, Yuji; Ueda, Masahito

    2006-01-01

    We develop a circuit theory that enables us to analyze quantum measurements on a two-level system and on a continuous-variable system on an equal footing. As a measurement scheme applicable to both systems, we discuss a swapping state measurement which exchanges quantum states between the system and the measuring apparatus before the apparatus meter is read out. This swapping state measurement has an advantage in gravitational-wave detection over contractive state measurement in that the post...

  7. CIRCUIT SWITCHING VERSUS PACKET SWITCHING

    OpenAIRE

    Sneps-Sneppe, Manfred

    2015-01-01

    Communication specialists around the world are facing the same problem: shifting from circuit switching (CS) to packet switching (CS). Communication service providers are favoring “All-over-IP” technologies hoping to boost their profits by providing multimedia services. The main stakeholder in this field of the paradigm shift is the industry itself: packet switching hardware manufacturers are going to earn billions of dollars and thus pay engineers and journalists many millions for the promot...

  8. 30 CFR 75.601-1 - Short circuit protection; ratings and settings of circuit breakers.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Short circuit protection; ratings and settings of circuit breakers. 75.601-1 Section 75.601-1 Mineral Resources MINE SAFETY AND HEALTH... Trailing Cables § 75.601-1 Short circuit protection; ratings and settings of circuit breakers....

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

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric equipment and circuits; overload and short circuit protection. 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....

  10. Quantum Circuits with Mixed States

    CERN Document Server

    Aharonov, D; Nisan, N; Aharonov, Dorit; Kitaev, Alexei; Nisan, Noam

    1998-01-01

    We define the model of quantum circuits with density matrices, where non-unitary gates are allowed. Measurements in the middle of the computation, noise and decoherence are implemented in a natural way in this model, which is shown to be equivalent in computational power to standard quantum circuits. The main result in this paper is a solution for the subroutine problem: The general function that a quantum circuit outputs is a probabilistic function, but using pure state language, such a function can not be used as a black box in other computations. We give a natural definition of using general subroutines, and analyze their computational power. We suggest convenient metrics for quantum computing with mixed states. For density matrices we analyze the so called ``trace metric'', and using this metric, we define and discuss the ``diamond metric'' on superoperators. These metrics enable a formal discussion of errors in the computation. Using a ``causality'' lemma for density matrices, we also prove a simple lowe...

  11. Anatomy of Scientific Evolution

    CERN Document Server

    Yun, Jinhyuk; Jeong, Hawoong

    2014-01-01

    The quest for historically impactful science and technology provides invaluable insight into the innovation dynamics of human society, yet many studies are limited to qualitative and small-scale approaches. Here, we investigate scientific evolution through systematic analysis of a massive corpus of digitized English texts between 1800 and 2008. Our analysis reveals remarkable predictability for long-prevailing scientific concepts based on the levels of their prior usage. Interestingly, once a threshold of early adoption rates is passed even slightly, scientific concepts can exhibit sudden leaps in their eventual lifetimes. We developed a mechanistic model to account for such results, indicating that slowly-but-commonly adopted science and technology surprisingly tend to have higher innate strength than fast-and-commonly adopted ones. The model prediction for disciplines other than science was also well verified. Our approach sheds light on unbiased and quantitative analysis of scientific evolution in society,...

  12. Russia's scientific legacy

    Science.gov (United States)

    2015-01-01

    Many insights of Russian scientists are unknown or long-forgotten outside of Russia. Making the Russian literature accessible to the international scientific community could stimulate new lines of research.

  13. Enhancing human capacities

    CERN Document Server

    Savulescu, Julian; Kahane, Guy

    2011-01-01

    Enhancing Human Capacities is the first to review the very latest scientific developments in human enhancement. It is unique in its examination of the ethical and policy implications of these technologies from a broad range of perspectives. Presents a rich range of perspectives on enhancement from world leading ethicists and scientists from Europe and North America The most comprehensive volume yet on the science and ethics of human enhancement Unique in providing a detailed overview of current and expected scientific advances in this area Discusses both general conceptual and ethical issues

  14. Preperation of Scientific Movies

    OpenAIRE

    Bülent Pekdağ

    2007-01-01

    This study aims to provide information on the preparation of the scientific movies as a part of Information and Communications Technology. The preparation stages of the scientific movies and their visualizations on computer screens were described. For preparing movies, the unit on the "acid-base reactions" on 11th grade French chemistry curriculum was used, and the knowledge presented in the movies was determined by an analysis of the 11th grade chemistry curriculum and the chemistry books. A...

  15. Shaping a Scientific Self

    DEFF Research Database (Denmark)

    Andrade-Molina, Melissa; Valero, Paola

    us to understand how a truth is reproduced, circulating among diverse fields of human knowledge. Also it will show why we accept and reproduce a particular discourse. Finally, we state Euclidean geometry as a truth that circulates in scientific discourse and performs a scientific self. We unfold the...... importance of having students following the path of what schools perceive a real scientist is, no to become a scientist, but to become a logical thinker, a problem solver, a productive citizen who uses reason....

  16. PLAGIARISM IN SCIENTIFIC PUBLISHING

    OpenAIRE

    Masic, Izet

    2012-01-01

    Scientific publishing is the ultimate product of scientist work. Number of publications and their quoting are measures of scientist success while unpublished researches are invisible to the scientific community, and as such nonexistent. Researchers in their work rely on their predecessors, while the extent of use of one scientist work, as a source for the work of other authors is the verification of its contributions to the growth of human knowledge. If the author has published an article in ...

  17. Model Order Reduction for Electronic Circuits:

    DEFF Research Database (Denmark)

    Hjorth, Poul G.; Shontz, Suzanne

    Electronic circuits are ubiquitous; they are used in numerous industries including: the semiconductor, communication, robotics, auto, and music industries (among many others). As products become more and more complicated, their electronic circuits also grow in size and complexity. This increased...... the need for circuit simulators to evaluate potential designs before fabrication, as integrated circuit prototypes are expensive to build, and troubleshooting is difficult. In this report, we focus on the simulation of printed circuit boards (PCB’s) and interconnects both of which are of great importance...

  18. Design of analog circuits through symbolic analysis

    CERN Document Server

    Fakhfakh, Mourad; V Fernández, Francisco

    2012-01-01

    Symbolic analyzers have the potential to offer knowledge to sophomores as well as practitioners of analog circuit design. Actually, they are an essential complement to numerical simulators, since they provide insight into circuit behavior which numerical analyzers do not provide. Symbolic analysis of electronic circuits addresses the generation of symbolic expressions for the parameters that describe the performance of linear and nonlinear circuits in three domains: DC, AC and time; some or all the circuit parameters can be kept as symbols. Due to the fact that these expressions remain va

  19. CMOS circuit design, layout and simulation

    CERN Document Server

    Baker, R Jacob

    2010-01-01

    The Third Edition of CMOS Circuit Design, Layout, and Simulation continues to cover the practical design of both analog and digital integrated circuits, offering a vital, contemporary view of a wide range of analog/digital circuit blocks including: phase-locked-loops, delta-sigma sensing circuits, voltage/current references, op-amps, the design of data converters, and much more. Regardless of one's integrated circuit (IC) design skill level, this book allows readers to experience both the theory behind, and the hands-on implementation of, complementary metal oxide semiconductor (CMOS) IC design via detailed derivations, discussions, and hundreds of design, layout, and simulation examples.

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

    Science.gov (United States)

    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.

  1. Faster Evolution of More Multifunctional Logic Circuits

    Science.gov (United States)

    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.

  2. Auto-programmable impulse neural circuits

    Science.gov (United States)

    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.

  3. Scientific collaboratories in higher education

    DEFF Research Database (Denmark)

    Sonnenwald, Diane H.; Li, Bin

    2003-01-01

    Scientific collaboratories hold the promise of providing students access to specialized scientific instruments, data and experts, enabling learning opportunities perhaps otherwise not available. However, evaluation of scientific collaboratories in higher education has lagged behind...

  4. Novel Sleep Transistor Techniques for Low Leakage Power Peripheral Circuits

    Directory of Open Access Journals (Sweden)

    Rajani H.P

    2012-09-01

    Full Text Available Static power consumption is a major concern in nanometre technologies. Along with technology scaling down and higher operating speeds of CMOS VLSI circuits, the leakage power is getting enhanced. As process geometries are becoming smaller, device density increases and threshold voltage as well as oxide thickness decrease to keep pace with performance. Two novel circuit techniques for leakage current reduction in inverters with and without state retention property are presented in this work. The powerdissipation during inactive (standby mode of operation can be significantly reduced compared to traditional power gating methods by these circuit techniques. The proposed circuit techniques are applied to inverters and the results are compared with earlier inverter leakage minimization techniques. Inverter buffer chains are designed using new state retention low leakage technique and found to be dissipatinglower power with state retention. All low leakage inverters are designed and simulated in cadence design environment using 90 nm technology files. The leakage power during sleep mode is found to be better by X 63 times for novel method. The total power dissipation has also reduced by a factor of X 3.5, compared to earlier sleepy keeper technique. The state retention feature is also good compared to earlier leakage power reduction methodologies.

  5. Michael Davis: 2006 award for distinguished scientific contributions.

    Science.gov (United States)

    2006-11-01

    Presents the citation for Michael Davis, who received the Award for Distinguished Scientific Contributions "for his major discoveries about the brain circuits underlying basic aspects of behavioral plasticity and learning." A brief profile and a selected bibliography, as well as Davis' award address, entitled Neural Systems Involved in Fear and Anxiety Measured With Fear-Potentiated Startle, accompany the citation. ((c) 2006 APA, all rights reserved). PMID:17115805

  6. Design-for-delay-testability techniques for high-speed digital circuits

    OpenAIRE

    Vermaak, Hermanus Jacobus

    2005-01-01

    The importance of delay faults is enhanced by the ever increasing clock rates and decreasing geometry sizes of nowadays' circuits. This thesis focuses on the development of Design-for-Delay-Testability (DfDT) techniques for high-speed circuits and embedded cores. The rising costs of IC testing and in particular the costs of Automatic Test Equipment are major concerns for the semiconductor industry. To reverse the trend of rising testing costs, DfDT is getting more and more important.

  7. EM-based optimization of microwave circuits using artificial neural networks: the state of the art

    OpenAIRE

    Rayas-Sánchez, José E.

    2004-01-01

    This paper reviews the current state-of-the-art in electromagnetic (EM)-based design and optimization of microwave circuits using artificial neural networks (ANNs). Measurement-based design of microwave circuits using ANNs is also reviewed. The conventional microwave neural optimization approach is surveyed, along with typical enhancing techniques, such as segmentation, decomposition, hierarchy, design of experiments and clusterization. Innovative strategies for ANN-based design exploiting...

  8. 46 CFR 28.860 - Overcurrent protection and switched circuits.

    Science.gov (United States)

    2010-10-01

    ... circuits having fused disconnect switches or circuit breakers so that only the appropriate navigation... breaker or fuse at the connection to the switchboard or distribution panel bus. (d) Each circuit breaker... steering circuit, each circuit must be protected against both overload and short circuit. Each...

  9. 14 CFR 23.1357 - Circuit protective devices.

    Science.gov (United States)

    2010-01-01

    ... circuit breakers, must be installed in all electrical circuits other than— (1) Main circuits of starter... circuit breaker or replace a fuse is essential to safety in flight, that circuit breaker or fuse must be... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Circuit protective devices. 23.1357...

  10. Scientific computer simulation review

    International Nuclear Information System (INIS)

    Before the results of a scientific computer simulation are used for any purpose, it should be determined if those results can be trusted. Answering that question of trust is the domain of scientific computer simulation review. There is limited literature that focuses on simulation review, and most is specific to the review of a particular type of simulation. This work is intended to provide a foundation for a common understanding of simulation review. This is accomplished through three contributions. First, scientific computer simulation review is formally defined. This definition identifies the scope of simulation review and provides the boundaries of the review process. Second, maturity assessment theory is developed. This development clarifies the concepts of maturity criteria, maturity assessment sets, and maturity assessment frameworks, which are essential for performing simulation review. Finally, simulation review is described as the application of a maturity assessment framework. This is illustrated through evaluating a simulation review performed by the U.S. Nuclear Regulatory Commission. In making these contributions, this work provides a means for a more objective assessment of a simulation’s trustworthiness and takes the next step in establishing scientific computer simulation review as its own field. - Highlights: • We define scientific computer simulation review. • We develop maturity assessment theory. • We formally define a maturity assessment framework. • We describe simulation review as the application of a maturity framework. • We provide an example of a simulation review using a maturity framework

  11. Scientific/Techical Report

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Chris Leighton, Neutron Scattering Society of American; Mr. J. Ardie (Butch) Dillen, MRS Director of Finance and Administration

    2012-11-07

    The ACNS provides a focal point for the North American neutron user community, strengthening ties within this diverse group, and promoting neutron research in related disciplines. The conference thus serves a dual role as both a national user meeting and a scientific meeting. As a venue for scientific exchange, the ACNS showcases recent results and provides a forum for scientific discussion of neutron-enabled research in fields as diverse as hard and soft condensed matter, liquids, biology, magnetism, engineering materials, chemical spectroscopy, crystal structure, elementary excitations, fundamental physics, and development of neutron instrumentation. This is achieved through a combination of invited oral presentations, contributed oral presentations, and poster sessions. Adequate opportunity for spontaneous discussion and collaboration is also built into the ACNS program in order to foster free exchange of new scientific ideas and the potential for use of powerful neutron scattering methods beyond the current realms of application. The sixth American Conference on Neutron Scattering (ACNS 2012) provided essential information on the breadth and depth of current neutron-related research worldwide. A strong program of plenary, invited and contributed talks showcased recent scientific results in neutron science in a wide range of fields, including soft and hard condensed matter, biology, chemistry, energy and engineering applications, and neutron physics.

  12. Acute effects of three different circuit weight training protocols on blood lactate, heart rate, and rating of perceived exertion in recreationally active women.

    Science.gov (United States)

    Skidmore, Brook L; Jones, Margaret T; Blegen, Mark; Matthews, Tracey D

    2012-01-01

    Interval and circuit weight training are popular training methods for maximizing time-efficiency, and are purported to deliver greater physiological benefits faster than traditional training methods. Adding interval training into a circuit weight-training workout may further enhance the benefits of circuit weight training by placing increased demands upon the cardiovascular system. Our purpose was to compare acute effects of three circuit weight training protocols 1) traditional circuit weight training, 2) aerobic circuit weight training, and 3) combined circuit weight-interval training on blood lactate (BLA), heart rate (HR), and ratings of perceived exertion (RPE). Eleven recreationally active women completed 7 exercise sessions. Session 1 included measurements of height, weight, estimated VO2max, and 13 repetition maximum (RM) testing of the weight exercises. Sessions 2-4 were held on non-consecutive days for familiarization with traditional circuit weight training (TRAD), aerobic circuit weight training (ACWT), and combined circuit weight-interval training (CWIT) protocols. In sessions 5-7, TRAD, ACWT, and CWIT were performed in a randomized order ≥ 72 hr apart for measures of BLA, HR, and RPE at pre-exercise and following each of three mini-circuit weight training stations. Repeated-measures ANOVAs yielded significant interactions (p workouts into exercise programming may enhance fitness benefits and maximize time-efficiency more so than traditional circuit training methods. PMID:24150076

  13. Radio frequency integrated circuit design

    CERN Document Server

    Rogers, John W M

    2010-01-01

    This newly revised and expanded edition of the 2003 Artech House classic, Radio Frequency Integrated Circuit Design, serves as an up-to-date, practical reference for complete RFIC know-how. The second edition includes numerous updates, including greater coverage of CMOS PA design, RFIC design with on-chip components, and more worked examples with simulation results. By emphasizing working designs, this book practically transports you into the authors' own RFIC lab so you can fully understand the function of each design detailed in this book. Among the RFIC designs examined are RF integrated LC

  14. Circuit for Driving Piezoelectric Transducers

    Science.gov (United States)

    Randall, David P.; Chapsky, Jacob

    2009-01-01

    The figure schematically depicts an oscillator circuit for driving a piezoelectric transducer to excite vibrations in a mechanical structure. The circuit was designed and built to satisfy application-specific requirements to drive a selected one of 16 such transducers at a regulated amplitude and frequency chosen to optimize the amount of work performed by the transducer and to compensate for both (1) temporal variations of the resonance frequency and damping time of each transducer and (2) initially unknown differences among the resonance frequencies and damping times of different transducers. In other words, the circuit is designed to adjust itself to optimize the performance of whichever transducer is selected at any given time. The basic design concept may be adaptable to other applications that involve the use of piezoelectric transducers in ultrasonic cleaners and other apparatuses in which high-frequency mechanical drives are utilized. This circuit includes three resistor-capacitor networks that, together with the selected piezoelectric transducer, constitute a band-pass filter having a peak response at a frequency of about 2 kHz, which is approximately the resonance frequency of the piezoelectric transducers. Gain for generating oscillations is provided by a power hybrid operational amplifier (U1). A junction field-effect transistor (Q1) in combination with a resistor (R4) is used as a voltage-variable resistor to control the magnitude of the oscillation. The voltage-variable resistor is part of a feedback control loop: Part of the output of the oscillator is rectified and filtered for use as a slow negative feedback to the gate of Q1 to keep the output amplitude constant. The response of this control loop is much slower than 2 kHz and, therefore, does not introduce significant distortion of the oscillator output, which is a fairly clean sine wave. The positive AC feedback needed to sustain oscillations is derived from sampling the current through the

  15. Model reduction for circuit simulation

    CERN Document Server

    Hinze, Michael; Maten, E Jan W Ter

    2011-01-01

    Simulation based on mathematical models plays a major role in computer aided design of integrated circuits (ICs). Decreasing structure sizes, increasing packing densities and driving frequencies require the use of refined mathematical models, and to take into account secondary, parasitic effects. This leads to very high dimensional problems which nowadays require simulation times too large for the short time-to-market demands in industry. Modern Model Order Reduction (MOR) techniques present a way out of this dilemma in providing surrogate models which keep the main characteristics of the devi

  16. HF radio systems and circuits

    CERN Document Server

    Sabin, William

    1998-01-01

    A comprehensive reference for the design of high frequency communications systems and equipment. This revised edition is loaded with practical data, much of which cannot be found in other reference books. Its approach to the subject follows the needs of an engineer from system definition and performance requirements down to the individual circuit elements that make up radio transmitters and receivers. The accompanying disk contains updated software on filters, matching networks and receiver analysis. SciTech Publishing also provides many other products related to Communication Systems Design.

  17. Pragmatic circuits signals and filters

    CERN Document Server

    Eccles, William

    2006-01-01

    Pragmatic Circuits: Signals and Filters is built around the processing of signals. Topics include spectra, a short introduction to the Fourier series, design of filters, and the properties of the Fourier transform. The focus is on signals rather than power. But the treatment is still pragmatic. For example, the author accepts the work of Butterworth and uses his results to design filters in a fairly methodical fashion. This third of three volumes finishes with a look at spectra by showing how to get a spectrum even if a signal is not periodic. The Fourier transform provides a way of dealing wi

  18. Scientific Collaborations: principles of WikiBridge Design

    CERN Document Server

    Leclercq, Eric

    2010-01-01

    Semantic wikis, wikis enhanced with Semantic Web technologies, are appropriate systems for community-authored knowledge models. They are particularly suitable for scientific collaboration. This paper details the design principles ofWikiBridge, a semantic wiki.

  19. Development, integration and testing of automated triggering circuit for hybrid DC circuit breaker

    International Nuclear Information System (INIS)

    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. (author)

  20. Plagiarism in scientific publishing.

    Science.gov (United States)

    Masic, Izet

    2012-12-01

    Scientific publishing is the ultimate product of scientist work. Number of publications and their quoting are measures of scientist success while unpublished researches are invisible to the scientific community, and as such nonexistent. Researchers in their work rely on their predecessors, while the extent of use of one scientist work, as a source for the work of other authors is the verification of its contributions to the growth of human knowledge. If the author has published an article in a scientific journal it cannot publish the article in any other journal h with a few minor adjustments or without quoting parts of the first article, which are used in another article. Copyright infringement occurs when the author of a new article with or without the mentioning the author used substantial portions of previously published articles, including tables and figures. Scientific institutions and universities should,in accordance with the principles of Good Scientific Practice (GSP) and Good Laboratory Practices (GLP) have a center for monitoring,security, promotion and development of quality research. Establish rules and compliance to rules of good scientific practice are the obligations of each research institutions,universities and every individual-researchers,regardless of which area of science is investigated. In this way, internal quality control ensures that a research institution such as a university, assume responsibility for creating an environment that promotes standards of excellence, intellectual honesty and legality. Although the truth should be the aim of scientific research, it is not guiding fact for all scientists. The best way to reach the truth in its study and to avoid the methodological and ethical mistakes is to consistently apply scientific methods and ethical standards in research. Although variously defined plagiarism is basically intended to deceive the reader's own scientific contribution. There is no general regulation of control of

  1. Making better scientific figures

    Science.gov (United States)

    Hawkins, Ed; McNeall, Doug

    2016-04-01

    In the words of the UK government chief scientific adviser "Science is not finished until it's communicated" (Walport 2013). The tools to produce good visual communication have never been so easily accessible to scientists as at the present. Correspondingly, it has never been easier to produce and disseminate poor graphics. In this presentation, we highlight some good practice and offer some practical advice in preparing scientific figures for presentation to peers or to the public. We identify common mistakes in visualisation, including some made by the authors, and offer some good reasons not to trust defaults in graphics software. In particular, we discuss the use of colour scales and share our experiences in running a social media campaign (http://tiny.cc/endrainbow) to replace the "rainbow" (also "jet", or "spectral") colour scale as the default in (climate) scientific visualisation.

  2. Scientific foundations of engineering

    CERN Document Server

    McKnight, Stephen

    2015-01-01

    Providing an overview of the foundations of engineering from a fundamental scientific and physical perspective, this book reinforces the basic scientific and mathematical principles which underpin a range of engineering disciplines and applications. It covers the basics of physics, including quantum physics, as well as some key topics in chemistry, making it a valuable resource for both students and professionals looking to gain a more coherent and interdisciplinary understanding of engineering systems. Throughout, the focus is on common features of physical systems (such as mechanical and electronic resonance), showing how the same underlying principles apply to different disciplines. Problems are provided at the end of each chapter including conceptual questions and examples to demonstrate the practical application of fundamental scientific principles. These include real-world examples, which are solvable using computational packages such as MATLAB.

  3. Distance learning course for scientific articles writting.

    Directory of Open Access Journals (Sweden)

    Míriam Gutiérrez Escobar

    2009-05-01

    Full Text Available Background: Scientific publications within Medical Sciences are an important factor for professionals to achieve services of excellence. However, the training to write this kind of articles is not enough. Objective: To design a theoretical and practical course of composition and style for scientific articles publications. Methods: Observational, descriptive, cross-sectional study including 50 professionals of the Medical School Branch. The main difficulties that they face to publish an article were determined and a distance learning course was designed on this basis, using the Moodle platform. Results: All the surveyed individuals referred that among the main causes limiting their ability to publish scientific articles are: little practical knowledge about the requirements to write scientific articles, not receiving any subject enhancing textual composition during their academic formation, and not attending to any post-graduate course aimed at improving academic writing for publication. A curse of 10 hours (theoretical part and 30 hours (practical part divide into five chapters including stylistic, methodological and compositional elements. Conclusions: This course helps improving the composition of scientific articles written by professional and their further publication in scientific journals.

  4. SCIENTIFIC STATUS OF DIDACTICS

    Directory of Open Access Journals (Sweden)

    I. M. Osmolovskaya

    2015-03-01

    Full Text Available The research is aimed at scientific justification of didactics referred to the social and humanitarian field of knowledge. The author deals with the scientific character criteria (verity, inter-subjectivity, systemacity and validity taking into account different scientific rationality types (classical and nonclassical and identifying post-modernism influence on didactics. Objectives and results of research. Attempts are made to systematize the didactic knowledge and identify its components and structure. Didactic concepts are classified in accordance with its objects: teaching process by the whole, its individual components or educative process aspects that enable to form definite teaching views, studying it from the specific positions. The author singles out holistic-didactic, component and aspect concepts; and specifies the concept of didactic systems and models with its hierarchy. The author highlights the didactic knowledge increment. Apart from traditional empirical theoretical researches, the author’s attention is drawn to the academic pursuit such as a scientific project based on the didactic object specificity of the teaching process which is fully human controlled and realized and doesn’texist without human being. It is shown that basic theoretical ideas of scientific projects are itemized, concretized and enlarged during co-current educative practice, i.e. an adhesion of theory and practice occurs.It is stressed that there are two special directions of didactic development multidimensionality: 1. extension of its semantic field in the context of modern socio-cultural conditions; 2. increase of scientific status related to a conceptual framework improvement, empirically accumulated information arrangement, new hypotheses, theories and concepts’ development. Scientific novelty. The research findings demonstrate well-reasoned statement of the didactics’ scientific status, its particular components and structure

  5. Rediscovering the scientific ethos

    DEFF Research Database (Denmark)

    Djørup, Stine

    The doctoral dissertation discusses some of the moral standards of good scientific practice that areunderexposed in the literature. In particular, attempts are made to correct the conceptual confusionsurrounding the norm of 'disinterestedness' in science (‘uhildethed’), and the norm of scientific...... integrity.This task involves not only a discussion of these norms is content, but also a discussion of the theoreticalconditions for their development. Thus, a number of normative assumptions of the modern debate onvalues in science (values in science debate) is being discussed.The thesis concludes that...

  6. Usability in Scientific Databases

    Directory of Open Access Journals (Sweden)

    Ana-Maria Suduc

    2012-07-01

    Full Text Available Usability, most often defined as the ease of use and acceptability of a system, affects the users' performance and their job satisfaction when working with a machine. Therefore, usability is a very important aspect which must be considered in the process of a system development. The paper presents several numerical data related to the history of the scientific research of the usability of information systems, as it is viewed in the information provided by three important scientific databases, Science Direct, ACM Digital Library and IEEE Xplore Digital Library, at different queries related to this field.

  7. ABOUT TRACK CIRCUIT CALCULATION METHOD DEPENDENT ON FERROMAGNET PROPERTIES IN CONDITIONS OF TRACTION CURRENT NOISE INFLUENCE

    Directory of Open Access Journals (Sweden)

    A. Yu. Zhuravlev

    2016-04-01

    Full Text Available Purpose. The work is intended to investigate the electromagnetic processes in impedance bond in order to improve noise immunity of track circuits (TC for safe railway operation. Methodology. To achieve this purpose the methods of scientific analysis, mathematical modelling, experimental study, a large-scale simulation were used. Findings. The work examined the interference affecting the normal performance of track circuits. To a large extent, part of track circuit damages account for failures in track circuit equipment. Track circuit equipment is connected directly to the track line susceptible to traction current interference, which causes changes in its electrical characteristics and electromagnetic properties. Normal operability, performance of the main operating modes of the track circuit is determined by previous calculation of its performance and compilation of regulatory tables. The classical method for determination of track circuit parameters was analysed. The classical calculation method assumes representation of individual sections of the electrical track circuit using the quadripole network with known coefficients, usually in the A-form. Determining the coefficients of linear element circuit creates no metrological or mathematical difficulties. However, in circuits containing nonlinear ferromagnets (FM, obtaining the coefficients on the entire induction change range in the cores is quite a difficult task because the classical methods of idling (I and short circuit (SC are not acceptable. This leads to complicated methods for determining both the module and the arguments of quadripole network coefficients. Instead of the classical method, the work proposed the method for calculating the track circuit dependent on nonlinear properties of ferromagnets. Originality. The article examines a new approach to the calculation of TC taking into account the losses in ferromagnets (FM, without determination of equivalent circuit quadripole

  8. Metadata Management in Scientific Computing

    CERN Document Server

    Seidel, Eric L

    2012-01-01

    Complex scientific codes and the datasets they generate are in need of a sophisticated categorization environment that allows the community to store, search, and enhance metadata in an open, dynamic system. Currently, data is often presented in a read-only format, distilled and curated by a select group of researchers. We envision a more open and dynamic system, where authors can publish their data in a writeable format, allowing users to annotate the datasets with their own comments and data. This would enable the scientific community to collaborate on a higher level than before, where researchers could for example annotate a published dataset with their citations. Such a system would require a complete set of permissions to ensure that any individual's data cannot be altered by others unless they specifically allow it. For this reason datasets and codes are generally presented read-only, to protect the author's data; however, this also prevents the type of social revolutions that the private sector has seen...

  9. Analog circuit design scalable analog circuit design, high speed D/A converters, RF power amplifiers

    CERN Document Server

    Huijsing, Johan

    2007-01-01

    Preface. Part I: Scalable Analog Circuit Design. Introduction. Scalable High-Speed Analog Circuit Design; M. Vertregt, P. Scholtens. Scalable High Resolution Mixed Mode Circuit Design; R.J. Brewer. Scalable 'High Voltages' Integrated Circuit Design for XDSL Type of Applications; D. Rossi. Scalability of Wire-Line Analog Front-Ends; K. Bult. Reusable IP Analog Circuit Design; J. Hauptmann, A. Wiesbauer, H. Weinberger. Process Migration Tools for Analog and Digital Circuits; K. Francken, G. Gielen. Part II: High-Speed D/A Converters. Introduction. Introduction to High-Speed Digital-to-Analog Con

  10. PSI scientific report 2010

    International Nuclear Information System (INIS)

    at. The substantial enhancement of the therapeutic efficacy of antibodies is reported on, as is the production of terbium radioisotopes for diagnostic and therapeutic applications in nuclear medicine. Non-homogeneous distribution of radionuclides in proton-irradiated liquid-metal targets is the topic covered in a further report and the precise simulation of high-intensity cyclotrons is reported on. The expanding horizons for proton therapy are examined. The report also reviews the Strategy and highlights of general energy research and deals with a Niobia-Ceria based multi-purpose catalyst for diesel exhaust gas after-treatment. High-flux solar-driven thermochemical dissociation of CO2 and H2O using ceria redox reactions and the characterisation of combustion processes by laser spectroscopic measuring techniques are further topics covered. Results of the first projects completed by the Competence Center Energy and Mobility CCEM are discussed, scientific findings on nuclear safety and the safety analysis of the EPR nuclear reactor are discussed, as is the improved retention of radioactive aerosols during a steam-generator tube rupture. Predictive sorption modelling of various substances in Bentonite and opalinus clay and a safety analysis of nuclear power plant systems and their operators are reported on. The characterisation of plutonium in mixed-oxide nuclear fuel by synchrotron radiation is reported on. The impact of the Eyjafjallajoekull volcano eruption on air quality and the detection of recent climatic changes in the Russian Altai are further atmospheric topics dealt with. Finally, the heuristic design for the technical characterisation of passenger vehicles is looked at. The report also lists the facilities available to external users and their use in 2010. Technology transfer is discussed and a statistical overview of the PSI in 2010 is presented. The comprehensive report is finalised with contact information and an extensive overview of publications made and

  11. The plastic scintillator detector calibration circuit for DAMPE

    Science.gov (United States)

    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%.

  12. Cavity enhanced second-order nonlinear quantum photonic logic circuits

    CERN Document Server

    Trivedi, Rahul; Majumdar, Arka

    2015-01-01

    A large obstacle for realizing quantum photonic logic is the weak optical nonlinearity of available materials, which results in large power consumption. In this paper, we argue that second order ($\\chi^{(2)}$) nonlinear optical devices are more suitable for achieving low power photonic logic. We present the theoretical design of all-optical logic with $\\chi^{(2)}$ nonlinear bimodal cavities and their networks. Using semiclassical models derived from the Wigner quasi-probability distribution function, we analyze the power consumption of networks implementing an optical AND gate and an optical latch. Comparison between the second and third order $(\\chi^{(3)})$ optical logic reveals that the $\\chi^{(2)}$ design outperforms the corresponding $\\chi^{(3)}$ design in terms of the gate power consumption at high quality factors. Specifically, using realistic estimates for the $\\chi^{(2)}$ and $\\chi^{(3)}$ susceptibilities of available materials we show that at cavity quality factors $\\sim 10^4$, optical logic designed...

  13. Cavity-Enhanced Second-Order Nonlinear Photonic Logic Circuits

    Science.gov (United States)

    Trivedi, Rahul; Khankhoje, Uday K.; Majumdar, Arka

    2016-05-01

    A large obstacle for realizing photonic logic is the weak optical nonlinearity of available materials, which results in large power consumption. In this paper, we present the theoretical design of all-optical logic with second-order (χ(2 )) nonlinear bimodal cavities and their networks. Using semiclassical models derived from the Wigner quasiprobability distribution function, we analyze the power consumption and signal-to-noise ratio (SNR) of networks implementing an optical and gate and an optical latch. A comparison between the second- and third-order (χ(3 )) optical logic reveals that, while the χ(3 ) design outperforms the χ(2 ) design in terms of the SNR for the same input power, employing the χ(3 ) nonlinearity necessitates the use of cavities with ultrahigh-quality factors (Q ˜106) to achieve a gate power consumption comparable to that of the χ(2 ) design at significantly smaller quality factors (Q ˜104). Using realistic estimates of the χ(2 ) and χ(3 ) nonlinear susceptibilities of available materials, we show that, at achievable quality factors (Q ˜104), the χ(2 ) design is an order of magnitude more energy efficient than the corresponding χ(3 ) design.

  14. Optimal condition of memristance enhancement circuit using external voltage source

    Directory of Open Access Journals (Sweden)

    Hiroya Tanaka

    2014-05-01

    Full Text Available Memristor provides nonlinear response in the current-voltage characteristic and the memristance is modulated using an external voltage source. We point out by solving nonlinear equations that an optimal condition of the external voltage source exists for maximizing the memristance in such modulation scheme. We introduce a linear function to describe the nonlinear time response and derive an important design guideline; a constant ratio of the frequency to the amplitude of the external voltage source maximizes the memristance. The analysis completely accounts for the memristance behavior.

  15. Physical synthesis of quantum circuits using templates

    Science.gov (United States)

    Mirkhani, Zahra; Mohammadzadeh, Naser

    2016-06-01

    Similar to traditional CMOS circuits, quantum circuit design flow is divided into two main processes: logic synthesis and physical design. Addressing the limitations imposed on optimization of the quantum circuit metrics because of no information sharing between logic synthesis and physical design processes, the concept of "physical synthesis" was introduced for quantum circuit flow, and a few techniques were proposed for it. Following that concept, in this paper a new approach for physical synthesis inspired by template matching idea in quantum logic synthesis is proposed to improve the latency of quantum circuits. Experiments show that by using template matching as a physical synthesis approach, the latency of quantum circuits can be improved by more than 23.55 % on average.

  16. Magnet excitation circuits for DESY II

    International Nuclear Information System (INIS)

    In contrast to the existing synchrotron, DESY II will, since it is a separated function machine, have 5 independent magnet circuits: 1 for dipoles, 2 for quadrupoles and 2 for sextupoles. Moreover the repetition frequency will be 12.5 Hz instead of 50 Hz. The present White circuit allows the resonance frequency to be changed by a factor of 4 and will be used for the dipoles. The other 4 resonant circuits will be built from new elements and the magnet impedances are chosen such that all the magnets of one circuit can be connected in series. The dipole circuit will be operated with the existing dc-power supply and a new ac-power source of 12 pulse cycloconverter type without circulating current will be installed. The quadrupole and sextupole circuits will be excited by combined ac- and dc-power supplies of the type used for the FNL booster synchrotron

  17. A concise guide to chaotic electronic circuits

    CERN Document Server

    Buscarino, Arturo; Frasca, Mattia; Sciuto, Gregorio

    2014-01-01

    This brief provides a source of instruction from which students can be taught about the practicalities of designing and using chaotic circuits. The text provides information on suitable materials, circuit design and schemes for design realization. Readers are then shown how to reproduce experiments on chaos and to design new ones. The text guides the reader easily from the basic idea of chaos to the laboratory test providing an experimental basis that can be developed for such applications as secure communications. This brief provides introductory information on sample chaotic circuits, includes coverage of their development, and the “gallery” section provides information on a wide range of circuits. Concise Guide to Chaotic Electronic Circuits will be useful to anyone running a laboratory class involving chaotic circuits and to students wishing to learn about them.

  18. Efficient Synthesis of Linear Reversible Circuits

    CERN Document Server

    Patel, K N; Hayes, J P

    2003-01-01

    In this paper we consider circuit synthesis for n-wire linear reversible circuits using the C-NOT gate library. These circuits are an important class of reversible circuits with applications to quantum computation. Previous algorithms, based on Gaussian elimination and LU-decomposition, yield circuits with O(n^2) gates in the worst-case. However, an information theoretic bound suggests that it may be possible to reduce this to as few as O(n^2/log n) gates. We present an algorithm that is optimal up to a multiplicative constant, as well as Theta(log n) times faster than previous methods. While our results are primarily asymptotic, simulation results show that even for relatively small n our algorithm is faster and yields more efficient circuits than the standard method. Generically our algorithm can be interpreted as a matrix decomposition algorithm, yielding an asymptotically efficient decomposition of a binary matrix into a product of elementary matrices.

  19. A Singularity in the Kirchhoff's Circuit Equations

    CERN Document Server

    Harsha, N R Sree

    2016-01-01

    Students often have difficulty in understanding qualitatively the behaviour of simple electric circuits. In particular, as different studies have shown, they find multiple batteries connected in multiple loops difficult to analyse. In a recent paper [Phys. Educ. 50 568 (2015)], we showed such an electric circuit, which consists of ideal batteries connected in parallel, that couldn't be solved by the existing circuit analysis methods. In this paper, we shall introduce a new mathematical method of solving simple electric circuits from the solutions of more general circuits and show that the currents, in this particular circuit, take the indeterminate 0/0 form. We shall also present some of the implications of teaching the method. We believe that the description presented in this paper should help the instructors in teaching the behaviour of multiple batteries connected in parallel.

  20. Analog VLSI neural network integrated circuits

    Science.gov (United States)

    Kub, F. J.; Moon, K. K.; Just, E. A.

    1991-01-01

    Two analog very large scale integration (VLSI) vector matrix multiplier integrated circuit chips were designed, fabricated, and partially tested. They can perform both vector-matrix and matrix-matrix multiplication operations at high speeds. The 32 by 32 vector-matrix multiplier chip and the 128 by 64 vector-matrix multiplier chip were designed to perform 300 million and 3 billion multiplications per second, respectively. An additional circuit that has been developed is a continuous-time adaptive learning circuit. The performance achieved thus far for this circuit is an adaptivity of 28 dB at 300 KHz and 11 dB at 15 MHz. This circuit has demonstrated greater than two orders of magnitude higher frequency of operation than any previous adaptive learning circuit.

  1. Developing the Critical Thinking Skills of Astrobiology Students through Creative and Scientific Inquiry

    OpenAIRE

    Foster, Jamie S.; Lemus, Judith D.

    2015-01-01

    Scientific inquiry represents a multifaceted approach to explore and understand the natural world. Training students in the principles of scientific inquiry can help promote the scientific learning process as well as help students enhance their understanding of scientific research. Here, we report on the development and implementation of a learning module that introduces astrobiology students to the concepts of creative and scientific inquiry, as well as provide practical exercises to build c...

  2. 1995 Scientific Report

    International Nuclear Information System (INIS)

    This annual scientific report of SCK-CEN presents a comprehensive coverage and research activities in the filed of (a) waste and site restoration (b) reactor safety and radiation protection (c) operation of BR2 Materials Testing Reactor and (d) services provided by the center (analysis for characterization of waste packages, nuclear measurements, low-level radioactivity measurements)

  3. Dorky Poll Scientific Fears

    CERN Multimedia

    2008-01-01

    The questions posed in yesterday's posts about hopes for 2008 were half of what we were asked by the Powers That Be. The other half: What scientific development do you fear you'll be blogging or reading about in 2008?

  4. Report of scientific results

    International Nuclear Information System (INIS)

    The findings of R+D activities of the HMI radiation chemistry department in the fields of pulsed radiolysis, reaction kinematics, insulators and plastics are presented as well as the scientific publications and lectures of HMI staff and visitors including theoretical contributions, theses and dissertations, and conference papers. (HK)

  5. Funding scientific open access

    International Nuclear Information System (INIS)

    In order to reduce the knowledge divide, more Open Access Journals (OAJ) are needed in all languages and scholarly subject areas that exercise peer-review or editorial quality control. To finance needed costs, it is discussed why and how to sell target specific advertisement by associating ads to given scientific keywords. (author)

  6. Scientific Report 2003

    International Nuclear Information System (INIS)

    The annual scientific report gives an overview of the R and D activities at the Belgian Nuclear Research Centre SCK-CEN in 2003. The report discusses progress and main achievements in the following areas: reactor safety, radioactive waste and clean-up, radiation protection, the BR2 reactor, nuclear research and society, managing nuclear knowledge, and fusion research

  7. Ethics and Scientific Publication

    Science.gov (United States)

    Benos, Dale J.; Fabres, Jorge; Farmer, John; Gutierrez, Jessica P.; Hennessy, Kristin; Kosek, David; Lee, Joo Hyoung; Olteanu, Dragos; Russell, Tara; Wang, Kai

    2005-01-01

    This article summarizes the major categories of ethical violations encountered during submission, review, and publication of scientific articles. We discuss data fabrication and falsification, plagiarism, redundant and duplicate publication, conflict of interest, authorship, animal and human welfare, and reviewer responsibility. In each section,…

  8. Scientific techniques in Egyptology

    International Nuclear Information System (INIS)

    The paper concerns the contribution made by scientific method to Egyptology, in the areas of dating, provenance and medicine. The dating techniques, the analysis techniques and the use of radiology to determine the lifestyle of ancient Egyptians are all described. (U.K.)

  9. Scientific techniques in Egyptology

    Energy Technology Data Exchange (ETDEWEB)

    Newton, G.W.A.

    1987-04-01

    The paper concerns the contribution made by scientific method to Egyptology, in the areas of dating, provenance and medicine. The dating techniques, the analysis techniques and the use of radiology to determine the lifestyle of ancient Egyptians are all described. (U.K.).

  10. Scientific Report 2001

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-04-01

    The annual scientific report gives an overview of the R and D activities at the Belgian Nuclear Research Centre SCK-CEN in 2001. The report discusses progress and main achievements in four principal areas: Radiation Protection, Radioactive Waste and Clean-up, Reactor Safety and the BR2 Reactor.

  11. Assessing Scientific Inquiry

    Science.gov (United States)

    Peters, Erin

    2008-01-01

    Assessing student-led, open-ended scientific inquiry holds a unique problem for classroom teachers because of the diverse skills and content that emerge from student work. This article provides tangible strategies for teachers to assess divergent student-generated inquiry in a manner that is manageable for teachers, informative for students, and…

  12. Scientific Report 2004

    International Nuclear Information System (INIS)

    The annual scientific report gives a summary overview of the research and development activities at the Belgian Nuclear Research Centre SCK-CEN in 2004. The report discusses progress and main achievements in the following areas: reactor safety, radioactive waste and clean-up, radiation protection, the BR2 reactor, nuclear research and society, managing nuclear knowledge and fusion research

  13. Scientific Report 2001

    International Nuclear Information System (INIS)

    The annual scientific report gives an overview of the R and D activities at the Belgian Nuclear Research Centre SCK-CEN in 2001. The report discusses progress and main achievements in four principal areas: Radiation Protection, Radioactive Waste and Clean-up, Reactor Safety and the BR2 Reactor

  14. Scientific Report 2006

    International Nuclear Information System (INIS)

    The annual scientific report gives a summary overview of the research and development activities at the Belgian Nuclear Research Centre SCK-CEN in 2006. The report discusses progress and main achievements in the following areas: reactor safety, radioactive waste and clean-up, radiation protection, the BR2 reactor, nuclear research and society, managing nuclear knowledge and fusion research

  15. Scientific Component Technology Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Kohn, S; Bosl, B; Dahlgren, T; Kumfert, G; Smith, S

    2003-02-07

    The laboratory has invested a significant amount of resources towards the development of high-performance scientific simulation software, including numerical libraries, visualization, steering, software frameworks, and physics packages. Unfortunately, because this software was not designed for interoperability and re-use, it is often difficult to share these sophisticated software packages among applications due to differences in implementation language, programming style, or calling interfaces. This LDRD Strategic Initiative investigated and developed software component technology for high-performance parallel scientific computing to address problems of complexity, re-use, and interoperability for laboratory software. Component technology is an extension of scripting and object-oriented software development techniques that specifically focuses on the needs of software interoperability. Component approaches based on CORBA, COM, and Java technologies are widely used in industry; however, they do not support massively parallel applications in science and engineering. Our research focused on the unique requirements of scientific computing on ASCI-class machines, such as fast in-process connections among components, language interoperability for scientific languages, and data distribution support for massively parallel SPMD components.

  16. Scientific Report 2005

    International Nuclear Information System (INIS)

    The annual scientific report gives a summary overview of the research and development activities at the Belgian Nuclear Research Centre SCK-CEN in 2005. The report discusses progress and main achievements in the following areas: reactor safety, radioactive waste and clean-up, radiation protection, the BR2 reactor, nuclear research and society, managing nuclear knowledge and fusion research

  17. Scientific Report 2007

    International Nuclear Information System (INIS)

    This annual scientific report gives an concise overview of research and development activities at the Belgian Nuclear Research Centre SCK-CEN in 2007. The report discusses progress and main achievements in the following areas: reactor safety, radioactive waste and clean-up, radiation protection, the BR2 reactor, nuclear research and society, managing nuclear knowledge and fusion research

  18. 2003 Scientific Technological Report

    International Nuclear Information System (INIS)

    This annual scientific-technological report provides an overview of research and development activities at Peruvian Institute of Nuclear Energy (IPEN) during the period from 1 january to 31 december, 2003. This report includes 54 papers divided in 9 subject matters: physics and nuclear chemistry, nuclear engineering, materials science, radiochemistry, industrial applications, medical applications, environmental applications, protection and radiological safety, and management aspects

  19. Gain Enhanced LTCC System-on-Package for UMRR Applications

    KAUST Repository

    Shamim, Atif

    2014-10-14

    An apparatus, system, and method for Gain Enhanced LTCC System-on-Package radar sensor. The sensor includes a substrate and an integrated circuit coupled to the substrate, where the integrated circuit is configured to transmit and receive radio frequency (RF) signals. An antenna may be coupled to the integrated circuit and a lens may be coupled to the antenna. The lens may be configured to enhance the gain of the sensor.

  20. Worst Asymmetrical Short-Circuit Current

    DEFF Research Database (Denmark)

    Arana Aristi, Iván; Holmstrøm, O; Grastrup, L;

    2010-01-01

    In a typical power plant, the production scenario and the short-circuit time were found for the worst asymmetrical short-circuit current. Then, a sensitivity analysis on the missing generator values was realized in order to minimize the uncertainty of the results. Afterward the worst asymmetrical...... short-circuit current was analyzed in order to compare the results with the allowable DC current component based in the IEC. Finally the normal operating condition for the power plant was modeled....

  1. A Survey of Memristive Threshold Logic Circuits

    OpenAIRE

    Maan, Akshay Kumar; Jayadevi, Deepthi Anirudhan; James, Alex Pappachen

    2016-01-01

    In this paper, we review the different memristive threshold logic (MTL) circuits that are inspired from the synaptic action of flow of neurotransmitters in the biological brain. Brain like generalisation ability and area minimisation of these threshold logic circuits aim towards crossing the Moores law boundaries at device, circuits and systems levels.Fast switching memory, signal processing, control systems, programmable logic, image processing, reconfigurable computing, and pattern recognit...

  2. Logarithmic current-measuring transistor circuits

    DEFF Research Database (Denmark)

    Højberg, Kristian Søe

    1967-01-01

    Describes two transistorized circuits for the logarithmic measurement of small currents suitable for nuclear reactor instrumentation. The logarithmic element is applied in the feedback path of an amplifier, and only one dual transistor is used as logarithmic diode and temperature compensating...... transistor. A simple one-amplifier circuit is compared with a two-amplifier system. The circuits presented have been developed in connexion with an amplifier using a dual m.o.s. transistor input stage with diode-protected gates....

  3. Integrated-Circuit Pseudorandom-Number Generator

    Science.gov (United States)

    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.

  4. Theory of circuit block switch-off

    OpenAIRE

    S. Henzler; J. Berthold; G. Georgakos; Schmitt-Landsiedel, D.

    2005-01-01

    Switching-off unused circuit blocks is a promising approach to supress static leakage currents in ultra deep sub-micron CMOS digital systems. Basic performance parameters of Circuit Block Switch-Off (CBSO) schemes are defined and their dependence on basic circuit parameters is estimated. Therefore the design trade-off between strong leakage suppression in idle mode and adequate dynamic performance in active mode can be supported by simple analytic investigations. Additionally, a guideline for...

  5. Mnemonic Functions for Nonlinear Dendritic Integration in Hippocampal Pyramidal Circuits.

    Science.gov (United States)

    Kaifosh, Patrick; Losonczy, Attila

    2016-05-01

    We present a model for neural circuit mechanisms underlying hippocampal memory. Central to this model are nonlinear interactions between anatomically and functionally segregated inputs onto dendrites of pyramidal cells in hippocampal areas CA3 and CA1. We study the consequences of such interactions using model neurons in which somatic burst-firing and synaptic plasticity are controlled by conjunctive processing of these separately integrated input pathways. We find that nonlinear dendritic input processing enhances the model's capacity to store and retrieve large numbers of similar memories. During memory encoding, CA3 stores heavily decorrelated engrams to prevent interference between similar memories, while CA1 pairs these engrams with information-rich memory representations that will later provide meaningful output signals during memory recall. While maintaining mathematical tractability, this model brings theoretical study of memory operations closer to the hippocampal circuit's anatomical and physiological properties, thus providing a framework for future experimental and theoretical study of hippocampal function. PMID:27146266

  6. Trace-based post-silicon validation for VLSI circuits

    CERN Document Server

    Liu, Xiao

    2014-01-01

    This book first provides a comprehensive coverage of state-of-the-art validation solutions based on real-time signal tracing to guarantee the correctness of VLSI circuits.  The authors discuss several key challenges in post-silicon validation and provide automated solutions that are systematic and cost-effective.  A series of automatic tracing solutions and innovative design for debug (DfD) techniques are described, including techniques for trace signal selection for enhancing visibility of functional errors, a multiplexed signal tracing strategy for improving functional error detection, a tracing solution for debugging electrical errors, an interconnection fabric for increasing data bandwidth and supporting multi-core debug, an interconnection fabric design and optimization technique to increase transfer flexibility and a DfD design and associated tracing solution for improving debug efficiency and expanding tracing window. The solutions presented in this book improve the validation quality of VLSI circuit...

  7. EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA); Scientific Opinion on the substantiation of health claims related to caffeine and theobromine in cocoa (Theobroma cacao L.) and enhancement of mood (ID 4276) pursuant to Article 13(1) of Regulation (EC) No 1924/2006

    DEFF Research Database (Denmark)

    Tetens, Inge

    claims in relation to caffeine and theobromine in cocoa (Theobroma cacao L.) and enhancement of mood. The scientific substantiation is based on the information provided by the Member States in the consolidated list of Article 13 health claims and references that EFSA has received from Member States or...... directly from stakeholders. The food that is the subject of the health claim is cocoa (Theobroma cacao L.). The Panel considers that whereas the food, cocoa (Theobroma cacao L.), is not sufficiently characterised in relation to the claimed effect evaluated in this opinion, the food constituents, caffeine...... concludes that a cause and effect relationship has not been established between the consumption of caffeine and theobromine in cocoa (Theobroma cacao L.) and enhancement of mood....

  8. Hyperchaotic circuit with damped harmonic oscillators

    DEFF Research Database (Denmark)

    Lindberg, Erik; Murali, K.; Tamasevicius, A.

    2001-01-01

    A simple fourth-order hyperchaotic circuit with damped harmonic oscillators is described. ANP3 and PSpice simulations including an eigenvalue study of the linearized Jacobian are presented together with a hardware implementation. The circuit contains two inductors with series resistance, two ideal...... capacitors and one nonlinear active conductor. The Lyapunov exponents are presented to confirm the hyperchaotic nature of the oscillations of the circuit. The nonlinear conductor is realized with a diode. A negative impedance converter and a linear resistor. The performance of the circuit is investigated by...

  9. Analog circuit design art, science, and personalities

    CERN Document Server

    Williams, Jim

    1991-01-01

    Analog Circuit Design: Art, Science, and Personalities discusses the many approaches and styles in the practice of analog circuit design. The book is written in an informal yet informative manner, making it easily understandable to those new in the field. The selection covers the definition, history, current practice, and future direction of analog design; the practice proper; and the styles in analog circuit design. The book also includes the problems usually encountered in analog circuit design; approach to feedback loop design; and other different techniques and applications. The text is

  10. Modeling of transformers using circuit simulators

    Energy Technology Data Exchange (ETDEWEB)

    Archer, W.E.; Deveney, M.F.; Nagel, R.L.

    1994-07-01

    Transformers of two different designs; and unencapsulated pot core and an encapsulated toroidal core have been modeled for circuit analysis with circuit simulation tools. We selected MicroSim`s PSPICE and Anology`s SABER as the simulation tools and used experimental BH Loop and network analyzer measurements to generate the needed input data. The models are compared for accuracy and convergence using the circuit simulators. Results are presented which demonstrate the effects on circuit performance from magnetic core losses, eddy currents, and mechanical stress on the magnetic cores.

  11. High Speed Solid State Circuit Breaker

    Science.gov (United States)

    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.

  12. Power two-step dc circuit breaker

    International Nuclear Information System (INIS)

    A two-step circuit breaker with replaceable current-conducting elements is described. It is designed for a breakjng capacity of 6x109 W (the maximum current is 150 kA) with the 80-100 μs time of current transfer from inductive storage to the load and thermal stability of 1011 A2xs. A pneumatic circuit breaker with replaceable elements is used as the first step, and exploding-wire circuit breaker as the second one. The circuit breaker measures 1650x1360x1495 mm and weighs 1 t

  13. Electric circuit theory applied electricity and electronics

    CERN Document Server

    Yorke, R

    1981-01-01

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

  14. Circuit breaker maintenance, sentinels on guard

    Energy Technology Data Exchange (ETDEWEB)

    Tanguay, F.

    2003-07-01

    Circuit breakers are essential components of every type and size of power system, and their maintenance is a matter of prime importance. This article provides a list of typical circuit breaker maintenance routines for each type of insulating medium and each type of breaker mechanism, and offers a number of useful tips to ensure the success of a circuit breaker maintenance program. It also suggests sources of information about maintenance programs for circuit breakers such as the National Electrical Testing Association's Maintenance Specifications, and companies that specialize in this type of service. 3 tabs.

  15. The Scientific Competitiveness of Nations

    CERN Document Server

    Cimini, Giulio; Labini, Francesco Sylos

    2014-01-01

    We use citation data of scientific articles produced by individual nations in different scientific domains to determine the structure and efficiency of national research systems. We characterize the scientific fitness of each nation$-$that is, the competitiveness of its research system$-$and the complexity of each scientific domain by means of a non-linear iterative algorithm able to assess quantitatively the advantage of scientific diversification. We find that technological leading nations, beyond having the largest production of scientific papers and the largest number of citations, do not specialize in a few scientific domains. Rather, they diversify as much as possible their research system. On the other side, less developed nations are competitive only in scientific domains where also many other nations are present. Diversification thus represents the key element that correlates with scientific and technological competitiveness. A remarkable implication of this structure of the scientific competition is...

  16. Antenna-assisted enhanced transmission through subwavelength nanoholes

    DEFF Research Database (Denmark)

    Xiao, Sanshui; Peng, Liang; Mortensen, Asger

    2010-01-01

    By structural engineering of sub-wavelength apertures, we numerically demonstrate that transmission through apertures can be significantly enhanced. Based on equivalent circuit theory analysis, structured apertures are obtained with a 1900-fold transmission enhancement factor. We show that the...

  17. Expectations for a scientific collaboratory

    DEFF Research Database (Denmark)

    Sonnenwald, Diane H.

    2003-01-01

    In the past decade, a number of scientific collaboratories have emerged, yet adoption of scientific collaboratories remains limited. Meeting expectations is one factor that influences adoption of innovations, including scientific collaboratories. This paper investigates expectations scientists have...... with respect to scientific collaboratories. Interviews were conducted with 17 scientists who work in a variety of settings and have a range of experience conducting and managing scientific research. Results indicate that scientists expect a collaboratory to: support their strategic plans; facilitate...

  18. Scientific information management in the research education of Medicine students

    Directory of Open Access Journals (Sweden)

    Elso Manuel Cruz Cruz

    2009-09-01

    Full Text Available In any scientific research it is very important to achieve an appropriate information management to allow creating and transmitting new knowledge. In the context of the academic scientific activity, we approach the importance of including in the academic syllabus the training in scientific information searching in the Web. The reference to an experience in the medical school “Dr. Zoilo Marinello Vidaurreta” supports the idea of increasing the abilities and knowledge of students in scientific information searching from the academic years to enhance their research skills.

  19. Cortical feedback control of olfactory bulb circuits.

    Science.gov (United States)

    Boyd, Alison M; Sturgill, James F; Poo, Cindy; Isaacson, Jeffry S

    2012-12-20

    Olfactory cortex pyramidal cells integrate sensory input from olfactory bulb mitral and tufted (M/T) cells and project axons back to the bulb. However, the impact of cortical feedback projections on olfactory bulb circuits is unclear. Here, we selectively express channelrhodopsin-2 in olfactory cortex pyramidal cells and show that cortical feedback projections excite diverse populations of bulb interneurons. Activation of cortical fibers directly excites GABAergic granule cells, which in turn inhibit M/T cells. However, we show that cortical inputs preferentially target short axon cells that drive feedforward inhibition of granule cells. In vivo, activation of olfactory cortex that only weakly affects spontaneous M/T cell firing strongly gates odor-evoked M/T cell responses: cortical activity suppresses odor-evoked excitation and enhances odor-evoked inhibition. Together, these results indicate that although cortical projections have diverse actions on olfactory bulb microcircuits, the net effect of cortical feedback on M/T cells is an amplification of odor-evoked inhibition. PMID:23259951

  20. A Survey of Fast Analog Circuit Analysis Algorithm using SPICE

    OpenAIRE

    T.Murugajothi

    2014-01-01

    is paper presents a fast analog circuit analysis algorithm, fundamental circuit-based circuit analysis, for circuits being repeatedly modified and verified in product development. The algorithm reuses previous circuit simulation result on successive changed circuit analysis to achieve simulation operation reduction. The algorithm is implemented with SPICE simulator on linear and nonlinear circuit applications with the proposed device delta models. The experiments show that t...