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Sample records for analog electronics based

  1. Beginning analog electronics through projects

    CERN Document Server

    Singmin, Andrew

    2001-01-01

    Analog electronics is the simplest way to start a fun, informative, learning program. Beginning Analog Electronics Through Projects, Second Edition was written with the needs of beginning hobbyists and students in mind. This revision of Andrew Singmin's popular Beginning Electronics Through Projects provides practical exercises, building techniques, and ideas for useful electronics projects. Additionally, it features new material on analog and digital electronics, and new projects for troubleshooting test equipment.Published in the tradition of Beginning Electronics Through Projects an

  2. Mixing problem based learning and conventional teaching methods in an analog electronics course

    NARCIS (Netherlands)

    Podges, J M; Kommers, P A M; Winnips, K; van Joolingen, W R

    2014-01-01

    This study, undertaken at the Walter Sisulu University of Technology (WSU) in South Africa, describes how problem-based learning (PBL) affects the first year 'analog electronics course', when PBL and the lecturing mode is compared. Problems were designed to match real-life situations. Data between

  3. Mixing Problem Based Learning And Conventional Teaching Methods In An Analog Electronics Course

    NARCIS (Netherlands)

    Podges, J.M.; Kommers, Petrus A.M.; Winnips, K.; van Joolingen, Wouter

    2014-01-01

    This study, undertaken at the Walter Sisulu University of Technology (WSU) in South Africa, describes how problem-based learning (PBL) affects the first year ‘analog electronics course’, when PBL and the lecturing mode is compared. Problems were designed to match real-life situations. Data between

  4. Analog and mixed-signal electronics

    CERN Document Server

    Stephan, Karl

    2015-01-01

    A practical guide to analog and mixed-signal electronics, with an emphasis on design problems and applications This book provides an in-depth coverage of essential analog and mixed-signal topics such as power amplifiers, active filters, noise and dynamic range, analog-to-digital and digital-to-analog conversion techniques, phase-locked loops, and switching power supplies. Readers will learn the basics of linear systems, types of nonlinearities and their effects, op-amp circuits, the high-gain analog filter-amplifier, and signal generation. The author uses system design examples to motivate

  5. An Analog Computer for Electronic Engineering Education

    Science.gov (United States)

    Fitch, A. L.; Iu, H. H. C.; Lu, D. D. C.

    2011-01-01

    This paper describes a compact analog computer and proposes its use in electronic engineering teaching laboratories to develop student understanding of applications in analog electronics, electronic components, engineering mathematics, control engineering, safe laboratory and workshop practices, circuit construction, testing, and maintenance. The…

  6. Electronic devices for analog signal processing

    CERN Document Server

    Rybin, Yu K

    2012-01-01

    Electronic Devices for Analog Signal Processing is intended for engineers and post graduates and considers electronic devices applied to process analog signals in instrument making, automation, measurements, and other branches of technology. They perform various transformations of electrical signals: scaling, integration, logarithming, etc. The need in their deeper study is caused, on the one hand, by the extension of the forms of the input signal and increasing accuracy and performance of such devices, and on the other hand, new devices constantly emerge and are already widely used in practice, but no information about them are written in books on electronics. The basic approach of presenting the material in Electronic Devices for Analog Signal Processing can be formulated as follows: the study with help from self-education. While divided into seven chapters, each chapter contains theoretical material, examples of practical problems, questions and tests. The most difficult questions are marked by a diamon...

  7. Analog electronics for radiation detection

    CERN Document Server

    2016-01-01

    Analog Electronics for Radiation Detection showcases the latest advances in readout electronics for particle, or radiation, detectors. Featuring chapters written by international experts in their respective fields, this authoritative text: Defines the main design parameters of front-end circuitry developed in microelectronics technologies Explains the basis for the use of complementary metal oxide semiconductor (CMOS) image sensors for the detection of charged particles and other non-consumer applications Delivers an in-depth review of analog-to-digital converters (ADCs), evaluating the pros and cons of ADCs integrated at the pixel, column, and per-chip levels Describes incremental sigma delta ADCs, time-to-digital converter (TDC) architectures, and digital pulse-processing techniques complementary to analog processing Examines the fundamental parameters and front-end types associated with silicon photomultipliers used for single visible-light photon detection Discusses pixel sensors ...

  8. BPM ANALOG FRONT-END ELECTRONICS BASED ON THE AD8307 LOG AMPLIFIER

    International Nuclear Information System (INIS)

    R. SHURTER; ET AL

    2000-01-01

    Beam position monitor (BPM) signal-processing electronics utilizing the Analog Devices AD8307 logarithmic amplifier has been developed for the Low Energy Demonstration Accelerator (LEDA), part of the Accelerator Production of Tritium (APT) project at Los Alamos. The low-pass filtered 350 MHz fundamental signal from each of the four microstrip electrodes in a BPM is ''detected'' by an AD8307 log amp, amplified and scaled to accommodate the 0 to +5V input of an analog-to-digital (A/D) converter. The resultant four digitized signals represent a linear power relationship to the electrode signals, which are in turn related to beam current and position. As the AD8307 has a potential dynamic range of approximately 92 dB, much attention must be given to noise reduction, sources of which can be digital signals on the same board, power supplies, inter-channel coupling, stray RF and others. This paper will describe the operational experience of this particular analog front-end electronic circuit design

  9. Practical analog electronics for technicians

    CERN Document Server

    Kimber, W A

    2013-01-01

    'Practical Analog Electronics for Technicians' not only provides an accessible introduction to electronics, but also supplies all the problems and practical activities needed to gain hands-on knowledge and experience. This emphasis on practice is surprisingly unusual in electronics texts, and has already gained Will Kimber popularity through the companion volume, 'Practical Digital Electronics for Technicians'. Written to cover the Advanced GNVQ optional unit in electronics, this book is also ideal for BTEC National, A-level electronics and City & Guilds courses. Together with 'Practical Digit

  10. Foucault's pendulum, a classical analog for the electron spin state

    Science.gov (United States)

    Linck, Rebecca A.

    Spin has long been regarded as a fundamentally quantum phenomena that is incapable of being described classically. To bridge the gap and show that aspects of spin's quantum nature can be described classically, this work uses a classical Lagrangian based on the coupled oscillations of Foucault's pendulum as an analog for the electron spin state in an external magnetic field. With this analog it is possible to demonstrate that Foucault's pendulum not only serves as a basis for explaining geometric phase, but is also a basis for reproducing a broad range of behavior from Zeeman-like frequency splitting to precession of the spin state. By demonstrating that unmeasured electron spin states can be fully described in classical terms, this research opens the door to using the tools of classical physics to examine an inherently quantum phenomenon.

  11. Wideband continuous-time ΣΔ ADCs, automotive electronics, and power management : advances in analog circuit design 2016

    NARCIS (Netherlands)

    Baschirotto, A.; Harpe, P.J.A.; Makinwa, K.A.A.

    2017-01-01

    This book is based on the 18 tutorials presented during the 25th workshop on Advances in Analog Circuit Design. Expert designers present readers with information about a variety of topics at the frontier of analog circuit design, including low-power and energy-efficient analog electronics, with

  12. Programmable electronic system for analog and digital gamma cameras modernization

    International Nuclear Information System (INIS)

    Osorio Deliz, J. F.; Diaz Garcia, A.; Arista Omeu, E. J.

    2013-01-01

    At present the use of analog and digital gamma cameras is continuously increasing in developing countries. Many of them still largely rely in old hardware electronics, which in many cases limits their use in actual nuclear medicine diagnostic studies. For this reason worldwide there are different medical equipment manufacturing companies engaged into partial or total Gamma Cameras modernization. Nevertheless in several occasions acquisition prices are not affordable for developing countries. This work describes the basic features of a programmable electronic system that allows improving acquisitions functions and processing of analog and digital gamma cameras. This system is based on an electronic board for the acquisition and digitization of nuclear pulses which have been generated by gamma camera detector. It comprises a hardware interface with PC and the associated software to fully signal processing. Signal shaping and image processing are included. The extensive use of reference tables in the processing and signal imaging software allowed the optimization of the processing speed. Time design and system cost were also decreased. (Author)

  13. Analog Organic Electronics Building Blocks for Organic Smart Sensor Systems on Foil

    CERN Document Server

    Marien, Hagen; Heremans, Paul

    2013-01-01

     This book provides insight into organic electronics technology and in analog circuit techniques that can be used to increase the performance of both analog and digital organic circuits. It explores the domain of organic electronics technology for analog circuit applications, specifically smart sensor systems.  It focuses on all the building blocks in the data path of an organic sensor system between the sensor and the digital processing block. Sensors, amplifiers, analog-to-digital converters and DC-DC converters are discussed in detail. Coverage includes circuit techniques, circuit implementation, design decisions and measurement results of the building blocks described. Offers readers the first book to focus on analog organic circuit design; Discusses organic electronics technology for analog circuit applications in the context of smart sensor systems; Describes all building blocks necessary for an organic sensor system between the sensor and the digital processing block; Includes circuit techniques, cir...

  14. The Discourse on Printed and Electronic Books: Analogies, Oppositions, and Perspectives

    Science.gov (United States)

    Velagic, Zoran

    2014-01-01

    Introduction: The point of departure for this paper is the twofold analogy (analogy of content, analogy of medium) between printed and electronic books, the aim being to draw attention to the usual perception of their capacities and relationships, to provide a rather detailed analysis of the outcome and sustainability of such analogies and…

  15. Digital and Analog Electronics for an autonomous, deep-sea, Gamma Ray Burst Neutrino prototype detector

    Directory of Open Access Journals (Sweden)

    Manolopoulos K.

    2016-01-01

    Full Text Available GRBNeT is a Gamma Ray Burst Neutrino Telescope made of autonomously operated arrays of deep-sea light detectors, anchored to the sea-bed without any cabled connection to the shore. This paper presents the digital and analog electronics that we have designed and developed for the GRBNeT prototype. We describe the requirements for these electronics and present their design and functionality. We present low-power analog electronics for the PMTs utilized in the GRBNeT prototype and the FPGA based digital system for data selection and storage. We conclude with preliminary performance measurements of the electronics systems for the GRBNeT prototype.

  16. Analog synthetic biology.

    Science.gov (United States)

    Sarpeshkar, R

    2014-03-28

    We analyse the pros and cons of analog versus digital computation in living cells. Our analysis is based on fundamental laws of noise in gene and protein expression, which set limits on the energy, time, space, molecular count and part-count resources needed to compute at a given level of precision. We conclude that analog computation is significantly more efficient in its use of resources than deterministic digital computation even at relatively high levels of precision in the cell. Based on this analysis, we conclude that synthetic biology must use analog, collective analog, probabilistic and hybrid analog-digital computational approaches; otherwise, even relatively simple synthetic computations in cells such as addition will exceed energy and molecular-count budgets. We present schematics for efficiently representing analog DNA-protein computation in cells. Analog electronic flow in subthreshold transistors and analog molecular flux in chemical reactions obey Boltzmann exponential laws of thermodynamics and are described by astoundingly similar logarithmic electrochemical potentials. Therefore, cytomorphic circuits can help to map circuit designs between electronic and biochemical domains. We review recent work that uses positive-feedback linearization circuits to architect wide-dynamic-range logarithmic analog computation in Escherichia coli using three transcription factors, nearly two orders of magnitude more efficient in parts than prior digital implementations.

  17. Graphene-on-semiconductor substrates for analog electronics

    Science.gov (United States)

    Lagally, Max G.; Cavallo, Francesca; Rojas-Delgado, Richard

    2016-04-26

    Electrically conductive material structures, analog electronic devices incorporating the structures and methods for making the structures are provided. The structures include a layer of graphene on a semiconductor substrate. The graphene layer and the substrate are separated by an interfacial region that promotes transfer of charge carriers from the surface of the substrate to the graphene.

  18. Foucault's Pendulum, Analog for an Electron Spin State

    Science.gov (United States)

    Linck, Rebecca

    2012-11-01

    The classical Lagrangian that describes the coupled oscillations of Foucault's pendulum presents an interesting analog to an electron's spin state in an external magnetic field. With a simple modification, this classical Lagrangian yields equations of motion that directly map onto the Schrodinger-Pauli Equation. This analog goes well beyond the geometric phase, reproducing a broad range of behavior from Zeeman-like frequency splitting to precession of the spin state. By demonstrating that unmeasured spin states can be fully described in classical terms, this research opens the door to using the tools of classical physics to examine an inherently quantum phenomenon.

  19. Electrochemical deposition of magnesium from analogous ionic liquid based on dimethylformamide

    International Nuclear Information System (INIS)

    Wang, Huaiyou; Jia, Yongzhong; Wang, Xiaohua; Yao, Ying; Yue, Duyuan; Jing, Yan

    2013-01-01

    In this paper, a homogeneous, colorless analogous ionic liquid containing dimethylformamide (DMF) and magnesium chloride hexahydrate is synthesized. The conductivity of analogous ionic liquid is measured as a function of temperature and composition. Irreversible electrochemical behavior was generally observed by cyclic voltammetry (CV) in the analogous ionic liquid based electrolytes containing simple Mg salt. CV also shows that the reducing reaction of Mg 2+ is a diffusion control process. Electrochemical impedance spectroscopy (EIS) of analogous ionic liquid was measured at 20 °C, 40 °C and 60 °C. Electrodeposition of magnesium metal from analogous ionic liquid has been studied. The Mg deposits are also systematically characterized by the techniques of powder X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). Results showed that magnesium was found in the deposited film

  20. Analog Electronic Filters Theory, Design and Synthesis

    CERN Document Server

    Dimopoulos, Hercules G

    2012-01-01

    Filters are essential subsystems in a huge variety of electronic systems. Filter applications are innumerable; they are used for noise reduction, demodulation, signal detection, multiplexing, sampling, sound and speech processing, transmission line equalization and image processing, to name just a few. In practice, no electronic system can exist without filters. They can be found in everything from power supplies to mobile phones and hard disk drives and from loudspeakers and MP3 players to home cinema systems and broadband Internet connections. This textbook introduces basic concepts and methods and the associated mathematical and computational tools employed in electronic filter theory, synthesis and design.  This book can be used as an integral part of undergraduate courses on analog electronic filters. Includes numerous, solved examples, applied examples and exercises for each chapter. Includes detailed coverage of active and passive filters in an independent but correlated manner. Emphasizes real filter...

  1. 25th workshop on Advances in Analog Circuit Design

    CERN Document Server

    Harpe, Pieter; Makinwa, Kofi

    2017-01-01

    This book is based on the 18 tutorials presented during the 25th workshop on Advances in Analog Circuit Design. Expert designers present readers with information about a variety of topics at the frontier of analog circuit design, including low-power and energy-efficient analog electronics, with specific contributions focusing on the design of continuous-time sigma-delta modulators, automotive electronics, and power management. This book serves as a valuable reference to the state-of-the-art, for anyone involved in analog circuit research and development.

  2. Analog Multilayer Perceptron Circuit with On-chip Learning: Portable Electronic Nose

    Science.gov (United States)

    Pan, Chih-Heng; Tang, Kea-Tiong

    2011-09-01

    This article presents an analog multilayer perceptron (MLP) neural network circuit with on-chip back propagation learning. This low power and small area analog MLP circuit is proposed to implement as a classifier in an electronic nose (E-nose). Comparing with the E-nose using microprocessor or FPGA as a classifier, the E-nose applying analog circuit as a classifier can be faster and much smaller, demonstrate greater power efficiency and be capable of developing a portable E-nose [1]. The system contains four inputs, four hidden neurons, and only one output neuron; this simple structure allows the circuit to have a smaller area and less power consumption. The circuit is fabricated using TSMC 0.18 μm 1P6M CMOS process with 1.8 V supply voltage. The area of this chip is 1.353×1.353 mm2 and the power consumption is 0.54 mW. Post-layout simulations show that the proposed analog MLP circuit can be successively trained to identify three kinds of fruit odors.

  3. Advances in Analog Circuit Design 2015

    CERN Document Server

    Baschirotto, Andrea; Harpe, Pieter

    2016-01-01

    This book is based on the 18 tutorials presented during the 24th workshop on Advances in Analog Circuit Design. Expert designers present readers with information about a variety of topics at the frontier of analog circuit design, including low-power and energy-efficient analog electronics, with specific contributions focusing on the design of efficient sensor interfaces and low-power RF systems. This book serves as a valuable reference to the state-of-the-art, for anyone involved in analog circuit research and development. ·         Provides a state-of-the-art reference in analog circuit design, written by experts from industry and academia; ·         Presents material in a tutorial-based format; ·         Includes coverage of high-performance analog-to-digital and digital to analog converters, integrated circuit design in scaled technologies, and time-domain signal processing.

  4. Analysis and application of analog electronic circuits to biomedical instrumentation

    CERN Document Server

    Northrop, Robert B

    2012-01-01

    All chapters include an introduction and chapter summary.Sources and Properties of Biomedical SignalsSources of Endogenous Bioelectric SignalsNerve Action PotentialsMuscle Action PotentialsThe ElectrocardiogramOther BiopotentialsElectrical Properties of BioelectrodesExogenous Bioelectric SignalsProperties and Models of Semiconductor Devices Used in Analog Electronic Systemspn Junction DiodesMidfrequency Models for BJT BehaviorMidfrequency Models for Field-Effect TransistorsHigh-Frequency Models for Transistors and Simple Transistor AmplifiersPhotons, Photodiodes, Photoconductors, LEDs, and Las

  5. Studies of chaos and thermal noise in a driven Josephson junction using an electronic analog

    International Nuclear Information System (INIS)

    Pegrum, C.M.; Gurney, W.S.C.; Nisbet, R.M.

    1989-01-01

    Using an electronic analog of a resistively shunted driven Josephson junction, the authors have demonstrated a number of effects, including the appearance of a devil's staircase in the current-voltage characteristic, the onset of chaos, and the effect of noise on these phenomena. The authors stress that the analog is simple, but models the junction behavior with a high degree of accuracy and detail

  6. Analog computing

    CERN Document Server

    Ulmann, Bernd

    2013-01-01

    This book is a comprehensive introduction to analog computing. As most textbooks about this powerful computing paradigm date back to the 1960s and 1970s, it fills a void and forges a bridge from the early days of analog computing to future applications. The idea of analog computing is not new. In fact, this computing paradigm is nearly forgotten, although it offers a path to both high-speed and low-power computing, which are in even more demand now than they were back in the heyday of electronic analog computers.

  7. Documentary Realism, Sampling Theory and Peircean Semiotics: electronic audiovisual signs (analog or digital as indexes of reality

    Directory of Open Access Journals (Sweden)

    Hélio Godoy

    2007-07-01

    Full Text Available This paper addresses Documentary Realism, focusing on thephysical phenomena of transduction that take place in analog and digital audiovisual systems, herein analyzed in the light of the Sampling Theory, within the framework of Shannon and Weaver’s Information Theory. Transduction is a process by which one type of energy is transformed into another, or by which information is transcodified. Within the scope of Documentary Realism, it cannotbe claimed that electronic audiovisual signs, because of their technical digital features lead to a rupture with reality. Rather, the digital documentary, based on electronic digital cinematography, is still an index of reality.

  8. Analog-to-digital conversion

    CERN Document Server

    Pelgrom, Marcel J M

    2010-01-01

    The design of an analog-to-digital converter or digital-to-analog converter is one of the most fascinating tasks in micro-electronics. In a converter the analog world with all its intricacies meets the realm of the formal digital abstraction. Both disciplines must be understood for an optimum conversion solution. In a converter also system challenges meet technology opportunities. Modern systems rely on analog-to-digital converters as an essential part of the complex chain to access the physical world. And processors need the ultimate performance of digital-to-analog converters to present the results of their complex algorithms. The same progress in CMOS technology that enables these VLSI digital systems creates new challenges for analog-to-digital converters: lower signal swings, less power and variability issues. Last but not least, the analog-to-digital converter must follow the cost reduction trend. These changing boundary conditions require micro-electronics engineers to consider their design choices for...

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

    Science.gov (United States)

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

    2014-01-01

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

  10. 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

  11. Response matrix Monte Carlo based on a general geometry local calculation for electron transport

    International Nuclear Information System (INIS)

    Ballinger, C.T.; Rathkopf, J.A.; Martin, W.R.

    1991-01-01

    A Response Matrix Monte Carlo (RMMC) method has been developed for solving electron transport problems. This method was born of the need to have a reliable, computationally efficient transport method for low energy electrons (below a few hundred keV) in all materials. Today, condensed history methods are used which reduce the computation time by modeling the combined effect of many collisions but fail at low energy because of the assumptions required to characterize the electron scattering. Analog Monte Carlo simulations are prohibitively expensive since electrons undergo coulombic scattering with little state change after a collision. The RMMC method attempts to combine the accuracy of an analog Monte Carlo simulation with the speed of the condensed history methods. Like condensed history, the RMMC method uses probability distributions functions (PDFs) to describe the energy and direction of the electron after several collisions. However, unlike the condensed history method the PDFs are based on an analog Monte Carlo simulation over a small region. Condensed history theories require assumptions about the electron scattering to derive the PDFs for direction and energy. Thus the RMMC method samples from PDFs which more accurately represent the electron random walk. Results show good agreement between the RMMC method and analog Monte Carlo. 13 refs., 8 figs

  12. Fast event recorder utilizing a CCD analog shift register

    International Nuclear Information System (INIS)

    Ducar, R.J.; McIntyre, P.M.

    1978-01-01

    A system of electronics has been developed to allow the capture and recording of relatively fast, low-amplitude analog events. The heart of the system is a dual 455-cell analog shift register charge-coupled device, Fairchild CCD321ADC-3. The CCD is operated in a dual clock mode. The input is sampled at a selectable clock rate of .25-20 MHz. The stored analog data is then clocked out at a slower rate, typically about .25 MHz. The time base expansion of the analog data allows for analog-to-digital conversion and memory storage using conventional medium-speed devices. The digital data is sequentially loaded into a static RAM and may then be block transferred to a computer. The analog electronics are housed in a single-width NIM module, and the RAM memory in a single-width CAMAC module. Each pair of modules provides six parallel channels. Cost is about $200.00 per channel. Applications are described for ionization imaging (TPC, IRC) and long-drift calorimetry in liquid argon

  13. Spanish Velar-Insertion and Analogy: A Usage-Based Diachronic Analysis

    Science.gov (United States)

    Fondow, Steven Richard

    2010-01-01

    The theory of Analogical and Exemplar Modeling (AEM) suggests renewed discussion of the formalization of analogy and its possible incorporation in linguistic theory. AEM is a usage-based model founded upon Exemplar Modeling (Bybee 2007, Pierrehumbert 2001) that utilizes several principles of the Analogical Modeling of Language (Skousen 1992, 1995,…

  14. Classical analog for electronic degrees of freedom in nonadiabatic collision processes

    International Nuclear Information System (INIS)

    Meyer, H.; Miller, W.H.

    1979-01-01

    It is shown how a formally exact classical analog can be defined for a finite dimensional (in Hilbert space) quantum mechanical system. This approach is then used to obtain a classical model for the electronic degrees of freedom in a molecular collision system, and the combination of this with the usual classical description of the heavy particle (i.e., nuclear) motion provides a completely classical model for the electronic and heavy particle degrees of freedom. The resulting equations of motion are shown to be equivalent to describing the electronic degrees of freedom by the time-dependent Schroedinger equation, the time dependence arising from the classical motion of the nuclei, the trajectory of which is determined by the quantum mechanical average (i.e., Ehrenfest) force on the nuclei. Quantizing the system via classical S-matrix theory is shown to provide a dynamically consistent description of nonadiabatic collision processes; i.e., different electronic transitions have different heavy particle trajectories and, for example, the total energy of the electronic and heavy particle degrees of freedom is conserved. Application of this classical model for the electronic degrees of freedom (plus classical S-matrix theory) to the two-state model problem shows that the approach provides a good description of the electronic dynamics

  15. Electrochemistry and electron paramagnetic resonance spectroscopy of cytochrome c and its heme-disrupted analogs.

    Science.gov (United States)

    Novak, David; Mojovic, Milos; Pavicevic, Aleksandra; Zatloukalova, Martina; Hernychova, Lenka; Bartosik, Martin; Vacek, Jan

    2018-02-01

    Cytochrome c (cyt c) is one of the most studied conjugated proteins due to its electron-transfer properties and ability to regulate the processes involved in homeostasis or apoptosis. Here we report an electrochemical strategy for investigating the electroactivity of cyt c and its analogs with a disrupted heme moiety, i.e. apocytochrome c (acyt c) and porphyrin cytochrome c (pcyt c). The electrochemical data are supplemented with low-temperature and spin-probe electron paramagnetic resonance (EPR) spectroscopy. The main contribution of this report is a complex evaluation of cyt c reduction and oxidation at the level of surface-localized amino acid residues and the heme moiety in a single electrochemical scan. The electrochemical pattern of cyt c is substantially different to both analogs acyt c and pcyt c, which could be applicable in further studies on the redox properties and structural stability of cytochromes and other hemeproteins. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Analog and hybrid computing

    CERN Document Server

    Hyndman, D E

    2013-01-01

    Analog and Hybrid Computing focuses on the operations of analog and hybrid computers. The book first outlines the history of computing devices that influenced the creation of analog and digital computers. The types of problems to be solved on computers, computing systems, and digital computers are discussed. The text looks at the theory and operation of electronic analog computers, including linear and non-linear computing units and use of analog computers as operational amplifiers. The monograph examines the preparation of problems to be deciphered on computers. Flow diagrams, methods of ampl

  17. Property-Based Monitoring of Analog and Mixed-Signal Systems

    Science.gov (United States)

    Havlicek, John; Little, Scott; Maler, Oded; Nickovic, Dejan

    In the recent past, there has been a steady growth of the market for consumer embedded devices such as cell phones, GPS and portable multimedia systems. In embedded systems, digital, analog and software components are combined on a single chip, resulting in increasingly complex designs that introduce richer functionality on smaller devices. As a consequence, the potential insertion of errors into a design becomes higher, yielding an increasing need for automated analog and mixed-signal validation tools. In the purely digital setting, formal verification based on properties expressed in industrial specification languages such as PSL and SVA is nowadays successfully integrated in the design flow. On the other hand, the validation of analog and mixed-signal systems still largely depends on simulation-based, ad-hoc methods. In this tutorial, we consider some ingredients of the standard verification methodology that can be successfully exported from digital to analog and mixed-signal setting, in particular property-based monitoring techniques. Property-based monitoring is a lighter approach to the formal verification, where the system is seen as a "black-box" that generates sets of traces, whose correctness is checked against a property, that is its high-level specification. Although incomplete, monitoring is effectively used to catch faults in systems, without guaranteeing their full correctness.

  18. An FPGA-Based Electronic Cochlea

    Directory of Open Access Journals (Sweden)

    M. P. Leong

    2003-06-01

    Full Text Available A module generator which can produce an FPGA-based implementation of an electronic cochlea filter with arbitrary precision is presented. Although hardware implementations of electronic cochlea models have traditionally used analog VLSI as the implementation medium due to their small area, high speed, and low power consumption, FPGA-based implementations offer shorter design times, improved dynamic range, higher accuracy, and a simpler computer interface. The tool presented takes filter coefficients as input and produces a synthesizable VHDL description of an application-optimized design as output. Furthermore, the tool can use simulation test vectors in order to determine the appropriate scaling of the fixed point precision parameters for each filter. The resulting model can be used as an accelerator for research in audition or as the front-end for embedded auditory signal processing systems. The application of this module generator to a real-time cochleagram display is also presented.

  19. Characterization of front-end electronics for CZT based handheld radioisotope identifier

    Energy Technology Data Exchange (ETDEWEB)

    Lombigit, L., E-mail: lojius@nm.gov.my [Malaysian Nuclear Agency, Bangi, 43000 Kajang, Selangor (Malaysia); Rahman, Nur Aira Abd; Mohamad, Glam Hadzir Patai; Ibrahim, Maslina Mohd; Yussup, Nolida; Yazid, Khairiah; Jaafar, Zainudin

    2016-01-22

    A radioisotope identifier device based on large volume Co-planar grid CZT detector is current under development at Malaysian Nuclear Agency. This device is planned to be used for in-situ identification of radioisotopes based on their unique energies. This work reports on electronics testing performed on the front-end electronics (FEE) analog section comprising charge sensitive preamplifier-pulse shaping amplifier chain. This test involves measurement of charge sensitivity, pulse parameters and electronics noise. This report also present some preliminary results on the spectral measurement obtained from gamma emitting radioisotopes.

  20. 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

  1. Computer-integrated environments for electronics problem by means of the analog simulator PSPICE; Komp`yuterno-integrirovannye sredy dlya problemnogo obucheniya po ehlektronike na osnove analogovogo simulyatora PSPICE

    Energy Technology Data Exchange (ETDEWEB)

    Mileva, I; Petrov, A; Pavlov, I [Plovdivskij Univ., Plovdiv (Bulgaria)

    1996-12-31

    For the problem teaching purpose the computer-integrated environments are developed for simulation of electronic circuits. CIE for study of typical analog electronic circuits called STUDENT`s MODULE are described. Simulation of electronic circuits carried out by means of the analog simulator PSPICE. 9 refs.; 3 figs.

  2. Electric dipole moment planning with a resurrected BNL Alternating Gradient Synchrotron electron analog ring

    Directory of Open Access Journals (Sweden)

    Richard M. Talman

    2015-07-01

    Full Text Available There has been much recent interest in directly measuring the electric dipole moments (EDM of the proton and the electron, because of their possible importance in the present day observed matter/antimatter imbalance in the Universe. Such a measurement will require storing a polarized beam of “frozen spin” particles, 15 MeV electrons or 230 MeV protons, in an all-electric storage ring. Only one such relativistic electric accelerator has ever been built—the 10 MeV “electron analog” ring at Brookhaven National Laboratory in 1954; it can also be referred to as the “AGS analog” ring to make clear it was a prototype for the Alternating Gradient Synchrotron (AGS proton ring under construction at that time at BNL. (Its purpose was to investigate nonlinear resonances as well as passage through “transition” with the newly invented alternating gradient proton ring design. By chance this electron ring, long since dismantled and its engineering drawings disappeared, would have been appropriate both for measuring the electron EDM and to serve as an inexpensive prototype for the arguably more promising, but 10 times more expensive, proton EDM measurement. Today it is cheaper yet to “resurrect” the electron analog ring by simulating its performance computationally. This is one purpose for the present paper. Most existing accelerator simulation codes cannot be used for this purpose because they implicitly assume magnetic bending. The new ual/eteapot code, described in detail in an accompanying paper, has been developed for modeling storage ring performance, including spin evolution, in electric rings. Illustrating its use, comparing its predictions with the old observations, and describing new expectations concerning spin evolution and code performance, are other goals of the paper. To set up some of these calculations has required a kind of “archeological physics” to reconstitute the detailed electron analog lattice design from a

  3. Analog Electronic Implementation of Unstable Dissipative Systems of Type I with Multi-Scrolls Displaced Along Space

    Science.gov (United States)

    Ontañón-García, L. J.; Lozoya-Ponce, R. E.

    2017-06-01

    Multi-scroll Unstable Dissipative Systems (UDS) in R3 which consist of piecewise linear systems are implemented electronically by means of analog computing. The scrolling behavior of the systems can be designed to oscillate along a specific axis or into space depending on the unstable and stable manifolds. In order for a multi-scroll attractor, this switching system must present at least two unstable hyperbolic focus-saddle equilibria with the same stability index, a negative real eigenvalue and a pair of complex conjugated eigenvalues with positive real part. Then, to displace the scrolls among the axes and space different switching control laws must be designed. By taking into consideration the mathematical expressions of the switching systems, the electronic implementations are carried out by means of operational amplifiers representing the real analog physical solution of the systems, from which the voltage is measured representing the states solution.

  4. Towards new analog read-out electronics for the HADES drift chamber system

    Energy Technology Data Exchange (ETDEWEB)

    Wiebusch, Michael [Goethe-Universitaet, Frankfurt (Germany); Collaboration: HADES-Collaboration

    2016-07-01

    Track reconstruction in HADES is realized with 24 planar, low-mass drift chambers (MDC). About 27000 drift cells provide precise spatial information of track hit points together with energy loss information, serving for particle ID. In order to handle high rates and track densities required at the future SIS100 accelerator at FAIR, an upgrade of the MDC system is necessary, i.e. by receiving additional redundant layers of drift cells in front of the magnet. This involves new front-end electronics, as the original analog read-out ASIC (ASD8) is no longer in stock and cannot be produced due to its legacy silicon process. Employing new FEE would allow to further increase the sensitivity, e.g. providing additional valuable information for the analysis. This contribution presents a market analysis of alternative state-of-the-art technologies for the analog read-out of drift chambers. Test procedures to evaluate the suitability for the HADES MDCs are discussed and preliminary results are shown. Emphasis is put on the benefits and possible implementations of using two separate analog channels for reading out a sense wire, i.e. a fast amplifier with a discriminator for recording the arrival time of the signal pulse and a slow integrating amplifier with a time-over-threshold discriminator to measure the total charge of the pulse.

  5. Analog Circuit Design Optimization Based on Evolutionary Algorithms

    Directory of Open Access Journals (Sweden)

    Mansour Barari

    2014-01-01

    Full Text Available This paper investigates an evolutionary-based designing system for automated sizing of analog integrated circuits (ICs. Two evolutionary algorithms, genetic algorithm and PSO (Parswal particle swarm optimization algorithm, are proposed to design analog ICs with practical user-defined specifications. On the basis of the combination of HSPICE and MATLAB, the system links circuit performances, evaluated through specific electrical simulation, to the optimization system in the MATLAB environment, for the selected topology. The system has been tested by typical and hard-to-design cases, such as complex analog blocks with stringent design requirements. The results show that the design specifications are closely met. Comparisons with available methods like genetic algorithms show that the proposed algorithm offers important advantages in terms of optimization quality and robustness. Moreover, the algorithm is shown to be efficient.

  6. Optical modulation techniques for analog signal processing and CMOS compatible electro-optic modulation

    Science.gov (United States)

    Gill, Douglas M.; Rasras, Mahmoud; Tu, Kun-Yii; Chen, Young-Kai; White, Alice E.; Patel, Sanjay S.; Carothers, Daniel; Pomerene, Andrew; Kamocsai, Robert; Beattie, James; Kopa, Anthony; Apsel, Alyssa; Beals, Mark; Mitchel, Jurgen; Liu, Jifeng; Kimerling, Lionel C.

    2008-02-01

    Integrating electronic and photonic functions onto a single silicon-based chip using techniques compatible with mass-production CMOS electronics will enable new design paradigms for existing system architectures and open new opportunities for electro-optic applications with the potential to dramatically change the management, cost, footprint, weight, and power consumption of today's communication systems. While broadband analog system applications represent a smaller volume market than that for digital data transmission, there are significant deployments of analog electro-optic systems for commercial and military applications. Broadband linear modulation is a critical building block in optical analog signal processing and also could have significant applications in digital communication systems. Recently, broadband electro-optic modulators on a silicon platform have been demonstrated based on the plasma dispersion effect. The use of the plasma dispersion effect within a CMOS compatible waveguide creates new challenges and opportunities for analog signal processing since the index and propagation loss change within the waveguide during modulation. We will review the current status of silicon-based electrooptic modulators and also linearization techniques for optical modulation.

  7. CMOS Analog IC Design: Fundamentals

    OpenAIRE

    Bruun, Erik

    2018-01-01

    This book is intended for use as the main textbook for an introductory course in CMOS analog integrated circuit design. It is aimed at electronics engineering students who have followed basic courses in mathematics, physics, circuit theory, electronics and signal processing. It takes the students directly from a basic level to a level where they can start working on simple analog IC design projects or continue their studies using more advanced textbooks in the field. A distinct feature of thi...

  8. The analog of Blanc's law for drift velocities of electrons in gas mixtures in weakly ionized plasma

    International Nuclear Information System (INIS)

    Chiflikian, R.V.

    1995-01-01

    The analog of Blanc's law for drift velocities of electrons in multicomponent gas mixtures in weakly ionized spatially homogeneous low-temperature plasma is derived. The obtained approximate-analytical expressions are valid for average electron energy in the 1--5 eV range typical for plasma conditions of low-pressure direct current (DC) discharges. The accuracy of these formulas is ±5%. The analytical criterion of the negative differential conductivity (NDC) of electrons in binary mixtures of gases is obtained. NDC of electrons is predicted in He:Kr and He:Xe rare gas mixtures. copyright 1995 American Institute of Physics

  9. Digital to analog resistive switching transition induced by graphene buffer layer in strontium titanate based devices.

    Science.gov (United States)

    Wan, Tao; Qu, Bo; Du, Haiwei; Lin, Xi; Lin, Qianru; Wang, Da-Wei; Cazorla, Claudio; Li, Sean; Liu, Sidong; Chu, Dewei

    2018-02-15

    Resistive switching behaviour can be classified into digital and analog switching based on its abrupt and gradual resistance change characteristics. Realizing the transition from digital to analog switching in the same device is essential for understanding and controlling the performance of the devices with various switching mechanisms. Here, we investigate the resistive switching in a device made with strontium titanate (SrTiO 3 ) nanoparticles using X-ray diffractometry, scanning electron microscopy, Raman spectroscopy, and direct electrical measurements. It is found that the well-known rupture/formation of Ag filaments is responsible for the digital switching in the device with Ag as the top electrode. To modulate the switching performance, we insert a reduced graphene oxide layer between SrTiO 3 and the bottom FTO electrode owing to its good barrier property for the diffusion of Ag ions and high out-of-plane resistance. In this case, resistive switching is changed from digital to analog as determined by the modulation of interfacial resistance under applied voltage. Based on that controllable resistance, potentiation and depression behaviours are implemented as well. This study opens up new ways for the design of multifunctional devices which are promising for memory and neuromorphic computing applications. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Designed cell consortia as fragrance-programmable analog-to-digital converters.

    Science.gov (United States)

    Müller, Marius; Ausländer, Simon; Spinnler, Andrea; Ausländer, David; Sikorski, Julian; Folcher, Marc; Fussenegger, Martin

    2017-03-01

    Synthetic biology advances the rational engineering of mammalian cells to achieve cell-based therapy goals. Synthetic gene networks have nearly reached the complexity of digital electronic circuits and enable single cells to perform programmable arithmetic calculations or to provide dynamic remote control of transgenes through electromagnetic waves. We designed a synthetic multilayered gaseous-fragrance-programmable analog-to-digital converter (ADC) allowing for remote control of digital gene expression with 2-bit AND-, OR- and NOR-gate logic in synchronized cell consortia. The ADC consists of multiple sampling-and-quantization modules sensing analog gaseous fragrance inputs; a gas-to-liquid transducer converting fragrance intensity into diffusible cell-to-cell signaling compounds; a digitization unit with a genetic amplifier circuit to improve the signal-to-noise ratio; and recombinase-based digital expression switches enabling 2-bit processing of logic gates. Synthetic ADCs that can remotely control cellular activities with digital precision may enable the development of novel biosensors and may provide bioelectronic interfaces synchronizing analog metabolic pathways with digital electronics.

  11. Wafer-level chip-scale packaging analog and power semiconductor applications

    CERN Document Server

    Qu, Shichun

    2015-01-01

    This book presents a state-of-art and in-depth overview in analog and power WLCSP design, material characterization, reliability, and modeling. Recent advances in analog and power electronic WLCSP packaging are presented based on the development of analog technology and power device integration. The book covers in detail how advances in semiconductor content, analog and power advanced WLCSP design, assembly, materials, and reliability have co-enabled significant advances in fan-in and fan-out with redistributed layer (RDL) of analog and power device capability during recent years. Along with new analog and power WLCSP development, the role of modeling is a key to assure successful package design. An overview of the analog and power WLCSP modeling and typical thermal, electrical, and stress modeling methodologies is also provided. This book also: ·         Covers the development of wafer-level power discrete packaging with regular wafer-level design concepts and directly bumping technology ·    �...

  12. Trap Healing for High-Performance Low-Voltage Polymer Transistors and Solution-Based Analog Amplifiers on Foil.

    Science.gov (United States)

    Pecunia, Vincenzo; Nikolka, Mark; Sou, Antony; Nasrallah, Iyad; Amin, Atefeh Y; McCulloch, Iain; Sirringhaus, Henning

    2017-06-01

    Solution-processed semiconductors such as conjugated polymers have great potential in large-area electronics. While extremely appealing due to their low-temperature and high-throughput deposition methods, their integration in high-performance circuits has been difficult. An important remaining challenge is the achievement of low-voltage circuit operation. The present study focuses on state-of-the-art polymer thin-film transistors based on poly(indacenodithiophene-benzothiadiazole) and shows that the general paradigm for low-voltage operation via an enhanced gate-to-channel capacitive coupling is unable to deliver high-performance device behavior. The order-of-magnitude longitudinal-field reduction demanded by low-voltage operation plays a fundamental role, enabling bulk trapping and leading to compromised contact properties. A trap-reduction technique based on small molecule additives, however, is capable of overcoming this effect, allowing low-voltage high-mobility operation. This approach is readily applicable to low-voltage circuit integration, as this work exemplifies by demonstrating high-performance analog differential amplifiers operating at a battery-compatible power supply voltage of 5 V with power dissipation of 11 µW, and attaining a voltage gain above 60 dB at a power supply voltage below 8 V. These findings constitute an important milestone in realizing low-voltage polymer transistors for solution-based analog electronics that meets performance and power-dissipation requirements for a range of battery-powered smart-sensing applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Analog Group Delay Equalizers Design Based on Evolutionary Algorithm

    Directory of Open Access Journals (Sweden)

    M. Laipert

    2006-04-01

    Full Text Available This paper deals with a design method of the analog all-pass filter designated for equalization of the group delay frequency response of the analog filter. This method is based on usage of evolutionary algorithm, the Differential Evolution algorithm in particular. We are able to design such equalizers to be obtained equal-ripple group delay frequency response in the pass-band of the low-pass filter. The procedure works automatically without an input estimation. The method is presented on solving practical examples.

  14. Structured Analog CMOS Design

    CERN Document Server

    Stefanovic, Danica

    2008-01-01

    Structured Analog CMOS Design describes a structured analog design approach that makes it possible to simplify complex analog design problems and develop a design strategy that can be used for the design of large number of analog cells. It intentionally avoids treating the analog design as a mathematical problem, developing a design procedure based on the understanding of device physics and approximations that give insight into parameter interdependences. The proposed transistor-level design procedure is based on the EKV modeling approach and relies on the device inversion level as a fundament

  15. Problems and Projects Based Approach For Analog Electronic Circuits' Course

    Directory of Open Access Journals (Sweden)

    Vahé Nerguizian

    2009-04-01

    Full Text Available New educational methods and approaches are recently introduced and implemented at several North American and European universities using Problems and Projects Based Approach (PPBA. The PPBA employs a teaching technique based mostly on competences/skills rather than only on knowledge. This method has been implemented and proven by several pedagogical instructors and authors at several educational institutions. This approach is used at different disciplines such as medicine, biology, engineering and many others. It has the advantage to improve the student's skills and the knowledge retention rate, and reflects the 21st century industrial/company needs and demands. Before implementing this approach to a course, a good resources preparation and planning is needed upfront by the responsible or instructor of the course to achieve the course and students related objectives. This paper presents the preparation, the generated documentation and the implementation of a pilot project utilizing PPBA education for a second year undergraduate electronic course over a complete semester, and for two different class groups (morning and evening groups. The outcome of this project (achieved goals, observed difficulties and lessons learned is presented based on different tools such as students 'in class' communication and feedback, different course evaluation forms and the professor/instructor feedback. Resources, challenges, difficulties and recommendations are also assessed and presented. The impact, the effect and the results (during and at the end of the academic fall session of the PPBA on students and instructor are discussed, validated, managed and communicated to help other instructor in taking appropriate approach decisions with respect to this new educational approach compared to the classical one.

  16. Analogy between gambling and measurement-based work extraction

    Science.gov (United States)

    Vinkler, Dror A.; Permuter, Haim H.; Merhav, Neri

    2016-04-01

    In information theory, one area of interest is gambling, where mutual information characterizes the maximal gain in wealth growth rate due to knowledge of side information; the betting strategy that achieves this maximum is named the Kelly strategy. In the field of physics, it was recently shown that mutual information can characterize the maximal amount of work that can be extracted from a single heat bath using measurement-based control protocols, i.e. using ‘information engines’. However, to the best of our knowledge, no relation between gambling and information engines has been presented before. In this paper, we briefly review the two concepts and then demonstrate an analogy between gambling, where bits are converted into wealth, and information engines, where bits representing measurements are converted into energy. From this analogy follows an extension of gambling to the continuous-valued case, which is shown to be useful for investments in currency exchange rates or in the stock market using options. Moreover, the analogy enables us to use well-known methods and results from one field to solve problems in the other. We present three such cases: maximum work extraction when the probability distributions governing the system and measurements are unknown, work extraction when some energy is lost in each cycle, e.g. due to friction, and an analysis of systems with memory. In all three cases, the analogy enables us to use known results in order to obtain new ones.

  17. DESIGN AND DEVELOPMENT SYSTEM OF ELECTRONIC CANDLE BASED ON MICROCONTROLLER

    Directory of Open Access Journals (Sweden)

    Yeli Fitri Lianuari

    2017-12-01

    Full Text Available In this paper is described how the assembly process of designing and developing a series of inflatable candles microkontroller. The series based on electronics is a simple circuit that utilizes condenser microphone as a sensor. The use of these components are suitable for use in an application circuit electronic candles where the workings of this series starts from LEDs that analogous to wax and then lit using a pushbutton that analogy as lighters, and a flame from the LED can be extinguished by blowing. The concept of this series is simple but could be developed into a series of more innovative and interesting. One development is to add the output of the LED running that made candles burn more lively and interesting. Running LED of this circuit works by using a transistor as a switch that controls power of Az IC 368 and IC Az 418 M J. To simplify the development process, combination of a series of electronic candles with LED running can be simulated using the software Livewire and Proteus. Results of designing and developing a tool is not a new thing or that have not been found but the result of this achievement can be a source of inspiring in the world of electronics that can later be developed further so that it becomes a result of more recent example, lights out with once pat.

  18. Precision analog signal processor for beam position measurements in electron storage rings

    International Nuclear Information System (INIS)

    Hinkson, J.A.; Unser, K.B.

    1995-05-01

    Beam position monitors (BPM) in electron and positron storage rings have evolved from simple systems composed of beam pickups, coaxial cables, multiplexing relays, and a single receiver (usually a analyzer) into very complex and costly systems of multiple receivers and processors. The older may have taken minutes to measure the circulating beam closed orbit. Today instrumentation designers are required to provide high-speed measurements of the beam orbit, often at the ring revolution frequency. In addition the instruments must have very high accuracy and resolution. A BPM has been developed for the Advanced Light Source (ALS) in Berkeley which features high resolution and relatively low cost. The instrument has a single purpose; to measure position of a stable stored beam. Because the pickup signals are multiplexed into a single receiver, and due to its narrow bandwidth, the receiver is not intended for single-turn studies. The receiver delivers normalized measurements of X and Y position entirely by analog means at nominally 1 V/mm. No computers are involved. No software is required. Bergoz, a French company specializing in precision beam instrumentation, integrated the ALS design m their new BPM analog signal processor module. Performance comparisons were made on the ALS. In this paper we report on the architecture and performance of the ALS prototype BPM

  19. Analog data transmission via fiber optics

    International Nuclear Information System (INIS)

    Cisneros, E.L.; Burgueno, G.F.

    1987-01-01

    In the SLAC Linear Collider Detector (SLD), as in most high-energy particle detectors, the electromagnetic noise environment is the limiting factor in electronic readout performance. Front-end electronics are particularly susceptible to electromagnetic interference (EMI), and great care has been taken to minimize its effects. The transfer of preprocessed analog signals from the detector environs, to the remote digital processing electronics, by conventional means (via metal conductors), may ultimately limit the performance of the system. Because it is highly impervious to EMI and ground loops, a fiber-optic medium has been chosen for the transmission of these signals. This paper describes several fiber-optic transmission schemes which satisfy the requirements of the SLD analog data transmission

  20. Analog data transmission via fiber optics

    International Nuclear Information System (INIS)

    Cisneros, E.L.; Burgueno, G.F.

    1986-10-01

    In the SLAC Linear Collider Detector (SLD), as in most high-energy particle detectors, the electromagnetic noise environment is the limiting factor in electronic readout performance. Front-end electronics are particulary susceptible to electromagnetic interference (EMI), and great care has been taken to minimize its effects. The transfer of preprocessed analog signals from the detector environs, to the remote digital processing electronics, by conventional means (via metal conductors), may ultimately limit the performance of the system. Because it is highly impervious to EMI and ground loops, a fiber-optic medium has been chosen for the transmission of these signals. This paper describes several fiber-optic transmission schemes which satisfy the requirements of the SLD analog data transmission

  1. Bandwidth tunable microwave photonic filter based on digital and analog modulation

    Science.gov (United States)

    Zhang, Qi; Zhang, Jie; Li, Qiang; Wang, Yubing; Sun, Xian; Dong, Wei; Zhang, Xindong

    2018-05-01

    A bandwidth tunable microwave photonic filter based on digital and analog modulation is proposed and experimentally demonstrated. The digital modulation is used to broaden the effective gain spectrum and the analog modulation is to get optical lines. By changing the symbol rate of data pattern, the bandwidth is tunable from 50 MHz to 700 MHz. The interval of optical lines is set according to the bandwidth of gain spectrum which is related to the symbol rate. Several times of bandwidth increase are achieved compared to a single analog modulation and the selectivity of the response is increased by 3.7 dB compared to a single digital modulation.

  2. Analog Front-End Electronics in Beam Instrumentation

    CERN Document Server

    Boscolo, A

    2005-01-01

    The work gives an overview of present and near future technological opportunities for the first analog conditioning and subsequent signal processing of sensor signal. The interactions between beam sensor capability, their signals characteristics and the system requirements are analyzed from different approaches as: full analog continuous, sampled time discrete, full digital time and amplitude discrete. Special attention will be given to the impact of measurement methods and new devices in circuits and instrumentation architecture design, especially from the metrological point of view. A lot of measurement methods and related systems have been developed in order to overcome technological drawbacks and to reach the best cost-performances ratio. By a system revamping, some of these still now show the capability of reaching the actual technological limits in a simpler way in many applications as: ADC, linear and non linear signal processing, ultra high speed logic, etc. These methods could be carried out by the n...

  3. Plant a tree in cyberspace: metaphor and analogy as design elements in Web-based learning environments.

    Science.gov (United States)

    Wolfe, C R

    2001-02-01

    Analogy and metaphor are figurative forms of communication that help people integrate new information with prior knowledge to facilitate comprehension and appropriate inferences. The novelty and versatility of the Web place cognitive burdens on learners that can be overcome through the use of analogies and metaphors. This paper explores three uses of figurative communication as design elements in Web-based learning environments, and provides empirical illustrations of each. First, extended analogies can be used as the basis of cover stories that create an analogy between the learner's position and a hypothetical situation. The Dragonfly Web pages make extensive use of analogous cover stories in the design of interactive decision-making games. Feedback from visitors, patterns of usage, and external reviews provide evidence of effectiveness. A second approach is visual analogies based on the principles of ecological psychology. An empirical example suggests that visual analogies are most effective when there is a one-to-one correspondence between the base and visual target analogs. The use of learner-generated analogies is a third approach. Data from an offline study with undergraduate science students are presented indicating that generating analogies are associated with significant improvements in the ability to place events in natural history on a time line. It is concluded that cyberspace itself might form the basis of the next guiding metaphor of mind.

  4. Synthetic Biology: A Unifying View and Review Using Analog Circuits.

    Science.gov (United States)

    Teo, Jonathan J Y; Woo, Sung Sik; Sarpeshkar, Rahul

    2015-08-01

    We review the field of synthetic biology from an analog circuits and analog computation perspective, focusing on circuits that have been built in living cells. This perspective is well suited to pictorially, symbolically, and quantitatively representing the nonlinear, dynamic, and stochastic (noisy) ordinary and partial differential equations that rigorously describe the molecular circuits of synthetic biology. This perspective enables us to construct a canonical analog circuit schematic that helps unify and review the operation of many fundamental circuits that have been built in synthetic biology at the DNA, RNA, protein, and small-molecule levels over nearly two decades. We review 17 circuits in the literature as particular examples of feedforward and feedback analog circuits that arise from special topological cases of the canonical analog circuit schematic. Digital circuit operation of these circuits represents a special case of saturated analog circuit behavior and is automatically incorporated as well. Many issues that have prevented synthetic biology from scaling are naturally represented in analog circuit schematics. Furthermore, the deep similarity between the Boltzmann thermodynamic equations that describe noisy electronic current flow in subthreshold transistors and noisy molecular flux in biochemical reactions has helped map analog circuit motifs in electronics to analog circuit motifs in cells and vice versa via a `cytomorphic' approach. Thus, a body of knowledge in analog electronic circuit design, analysis, simulation, and implementation may also be useful in the robust and efficient design of molecular circuits in synthetic biology, helping it to scale to more complex circuits in the future.

  5. Electronics for guitarists

    CERN Document Server

    Dailey, Denton J

    2014-01-01

    Electronics for Guitarists focuses on analog circuitry, and is written for the guitarist interested in transistor and vacuum tube-based amplifiers. Topics include discrete transistors and diodes, classical filter circuits, and vacuum tube-based amplifiers.

  6. Piezoelectric energy harvesting from colored fat-tailed fluctuations: An electronic analogy

    Directory of Open Access Journals (Sweden)

    J. I. Peña Rosselló

    2015-09-01

    Full Text Available Aiming to optimize piezoelectric energy harvesting from strongly col-ored fat-tailed fluctuations, we have recently studied the performance ofa monostable inertial device under a noise whose statistics depends on aparameter q (bounded for q 1.We have studied the interplay between the potential shape (interpolatingbetween square-well and harmonic-like behaviors and the noise’s statis-tics and spectrum, and showed that its output power grows as q increasesabove 1. We now report a real experiment on an electronic analog of theproposed system, which sheds light on its operating principle. Received: 20 Novembre 2014, Accepted: 7 September 2015; Edited by: C. A. Condat, G. J. Sibona; DOI:http://dx.doi.org/10.4279/PIP.070014 Cite as: J I Peña Rosselló, R Deza, J . Deza, H S Wio, Papers in Physics 7, 070014 (2015

  7. Precision analog signal processor for beam position measurements in electron storage rings

    International Nuclear Information System (INIS)

    Hinkson, J.A.; Unser, K.B.

    1995-01-01

    Beam position monitors (BPM) in electron and positron storage rings have evolved from simple systems composed of beam pickups, coaxial cables, multiplexing relays, and a single receiver (usually a analyzer) into very complex and costly systems of multiple receivers and processors. The older may have taken minutes to measure the circulating beam closed orbit. Today instrumentation designers are required to provide high-speed measurements of the beam orbit, often at the ring revolution frequency. In addition the instruments must have very high accuracy and resolution. A BPM has been developed for the Advanced Light Source (ALS) in Berkeley which features high resolution and relatively low cost. The instrument has a single purpose; to measure position of a stable stored beam. Because the pickup signals are multiplexed into a single receiver, and due to its narrow bandwidth, the receiver is not intended for single-turn studies. The receiver delivers normalized measurements of X and Y posit ion entirely by analog means at nominally 1 V/mm. No computers are involved. No software is required. Bergoz, a French company specializing in precision beam instrumentation, integrated the ALS design m their new BPM analog signal processor module. Performance comparisons were made on the ALS. In this paper we report on the architecture and performance of the ALS prototype BPM

  8. The LST analog read-out system of the ZEUS muon detector

    International Nuclear Information System (INIS)

    De Giorgi, M.; Abbiendi, G.; Bertolin, A.; Borsato, E.; Brugnera, R.; Carlin, R.; Dal Corso, F.; Dosselli, U.; Gasparini, F.; Limentani, S.; Morandin, M.; Pitacco, G.; Posocco, M.; Stanco, L.; Stroili, R.; Voci, C.; Zuin, F.

    1996-01-01

    A muon position detector based on limited streamer tubes has been built for the ZEUS experiment at the HERA e-p collider at Desy. The tubes are arranged in chambers equipped with electronics circuitry providing an analog read-out of induced signals on strips set orthogonal to the tube wires. The electronic module for charge amplification and conversion will be described including some results obtained from the complete system. (orig.)

  9. CMOS analog circuit design

    CERN Document Server

    Allen, Phillip E

    1987-01-01

    This text presents the principles and techniques for designing analog circuits to be implemented in a CMOS technology. The level is appropriate for seniors and graduate students familiar with basic electronics, including biasing, modeling, circuit analysis, and some familiarity with frequency response. Students learn the methodology of analog integrated circuit design through a hierarchically-oriented approach to the subject that provides thorough background and practical guidance for designing CMOS analog circuits, including modeling, simulation, and testing. The authors' vast industrial experience and knowledge is reflected in the circuits, techniques, and principles presented. They even identify the many common pitfalls that lie in the path of the beginning designer--expert advice from veteran designers. The text mixes the academic and practical viewpoints in a treatment that is neither superficial nor overly detailed, providing the perfect balance.

  10. Analogical reasoning for reliability analysis based on generic data

    Energy Technology Data Exchange (ETDEWEB)

    Kozin, Igor O

    1996-10-01

    The paper suggests using the systemic concept 'analogy' for the foundation of an approach to analyze system reliability on the basis of generic data, describing the method of structuring the set that defines analogical models, an approach of transition from the analogical model to a reliability model and a way of obtaining reliability intervals of analogous objects.

  11. Analogical reasoning for reliability analysis based on generic data

    International Nuclear Information System (INIS)

    Kozin, Igor O.

    1996-01-01

    The paper suggests using the systemic concept 'analogy' for the foundation of an approach to analyze system reliability on the basis of generic data, describing the method of structuring the set that defines analogical models, an approach of transition from the analogical model to a reliability model and a way of obtaining reliability intervals of analogous objects

  12. Low-voltage current-mode CMOS building blocks for field programmable analog arrays and application

    International Nuclear Information System (INIS)

    Madian, A.H.K.

    2007-01-01

    The role of analog integrated circuits in modem electronic systems remains important, even though digital circuits dominate the market for VLSI solutions. Analog systems have always played an essential role in interfacing digital electronics to the real world in applications such as analog signal processing and signal conditioning .Industrial process and motion control and biomedical measurements . In addition, analog solutions are becoming increasingly competitive with digital circuits for dense, low-power, high-speed applications in low-precision signal-processing. Because of the wide variety of analog functions required in electronic systems and the complexity of the signals (frequency, time, signal levels, parasitic), analog system design is very specialized and supported by a diverse set of CAD tools that are more difficult to integrate than those required for digital design. The drive towards shorter design cycles for analog integrated circuits has demanded the development of high performance analog circuits that are re configurable and suitable for CAD methodologies. the researcher here try to contribute in this filed

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

    Directory of Open Access Journals (Sweden)

    Maria José BM de Almeida

    2014-09-01

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

  14. Are all analogies created equal? Prefrontal cortical functioning may predict types of analogical reasoning.

    Science.gov (United States)

    Chrysikou, Evangelia G; Thompson-Schill, Sharon L

    2010-06-01

    Abstract The proposed theory can account for analogies based on learned relationships between elements in the source and target domains. However, its explanatory power regarding the discovery of new relationships during analogical reasoning is limited. We offer an alternative perspective for the role of PFC in analogical thought that may better address different types of analogical mappings.

  15. Image magnification based on similarity analogy

    International Nuclear Information System (INIS)

    Chen Zuoping; Ye Zhenglin; Wang Shuxun; Peng Guohua

    2009-01-01

    Aiming at the high time complexity of the decoding phase in the traditional image enlargement methods based on fractal coding, a novel image magnification algorithm is proposed in this paper, which has the advantage of iteration-free decoding, by using the similarity analogy between an image and its zoom-out and zoom-in. A new pixel selection technique is also presented to further improve the performance of the proposed method. Furthermore, by combining some existing fractal zooming techniques, an efficient image magnification algorithm is obtained, which can provides the image quality as good as the state of the art while greatly decrease the time complexity of the decoding phase.

  16. Pseudogap in the Eliashberg approach based on electron-phonon and electron-electron-phonon interaction

    Energy Technology Data Exchange (ETDEWEB)

    Szczesniak, R. [Institute of Physics, Czestochowa University of Technology (Poland); Institute of Physics, Jan Dlugosz University in Czestochowa (Poland); Durajski, A.P.; Duda, A.M. [Institute of Physics, Czestochowa University of Technology (Poland)

    2017-04-15

    The properties of the superconducting and the anomalous normal state were described by using the Eliashberg method. The pairing mechanism was reproduced with the help of the Hamiltonian, which models the electron-phonon and the electron-electron-phonon interaction (EEPh). The set of the Eliashberg equations, which determines the order parameter function (φ), the wave function renormalization factor (Z), and the energy shift function (χ), was derived. It was proven that for the sufficiently large values of the EEPh potential, the doping dependence of the order parameter (φ/Z) has the analogous course to that observed experimentally in cuprates. The energy gap in the electron density of states is induced by Z and χ - the contribution from φ is negligible. The electron density of states possesses the characteristic asymmetric form and the pseudogap is observed above the critical temperature. (copyright 2017 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. Component-Level Electronic-Assembly Repair (CLEAR) Spacecraft Circuit Diagnostics by Analog and Complex Signature Analysis

    Science.gov (United States)

    Oeftering, Richard C.; Wade, Raymond P.; Izadnegahdar, Alain

    2011-01-01

    The Component-Level Electronic-Assembly Repair (CLEAR) project at the NASA Glenn Research Center is aimed at developing technologies that will enable space-flight crews to perform in situ component-level repair of electronics on Moon and Mars outposts, where there is no existing infrastructure for logistics spares. These technologies must provide effective repair capabilities yet meet the payload and operational constraints of space facilities. Effective repair depends on a diagnostic capability that is versatile but easy to use by crew members that have limited training in electronics. CLEAR studied two techniques that involve extensive precharacterization of "known good" circuits to produce graphical signatures that provide an easy-to-use comparison method to quickly identify faulty components. Analog Signature Analysis (ASA) allows relatively rapid diagnostics of complex electronics by technicians with limited experience. Because of frequency limits and the growing dependence on broadband technologies, ASA must be augmented with other capabilities. To meet this challenge while preserving ease of use, CLEAR proposed an alternative called Complex Signature Analysis (CSA). Tests of ASA and CSA were used to compare capabilities and to determine if the techniques provided an overlapping or complementary capability. The results showed that the methods are complementary.

  18. Developing a 300C Analog Tool for EGS

    Energy Technology Data Exchange (ETDEWEB)

    Normann, Randy

    2015-03-23

    This paper covers the development of a 300°C geothermal well monitoring tool for supporting future EGS (enhanced geothermal systems) power production. This is the first of 3 tools planed. This is an analog tool designed for monitoring well pressure and temperature. There is discussion on 3 different circuit topologies and the development of the supporting surface electronics and software. There is information on testing electronic circuits and component. One of the major components is the cable used to connect the analog tool to the surface.

  19. FTU bolometer electronic system upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Pollastrone, Fabio, E-mail: fabio.pollastrone@enea.it [Associazione EURATOM-ENEA sulla Fusione, Via Enrico Fermi 45, 00044 Frascati, Rome (Italy); Neri, Carlo; Florean, Marco; Ciccone, Giovanni [Associazione EURATOM-ENEA sulla Fusione, Via Enrico Fermi 45, 00044 Frascati, Rome (Italy)

    2013-10-15

    Highlights: ► Design and realization of a new bolometer electronic system. ► Many improvements over the actual commercial system. ► Architecture based on digital electronic hardware with minimal analog front end. ► Auto off-set correction, real time visualization features and small system size. ► Test results for the electronic system. -- Abstract: The FTU (Frascati Tokamak Upgrade) requires a bolometer diagnostic in order to measure the total plasma radiation. The current diagnostic architecture is based on a full analog multichannel AC bolometer system, which uses a carrier frequency amplifier with a synchronous demodulation. Taking into account the technological upgrades in the field of electronics, it was decided to realize an upgrade for the bolometric electronic system by using a hybrid analog/digital implementation. The new system developed at the ENEA Frascati laboratories has many improvements, and mainly a massive system volume reduction, a good measurement linearity and a simplified use. The new hardware system consists of two subsystems: the Bolometer Digital Control and the Bolometer Analog System. The Bolometer Digital Control can control 16 bolometer bridges through the Bolometer Analog System. The Bolometer Digital Control, based on the FPGA architecture, is connected via Ethernet with a PC; therefore, it can receive commands settings from the PC and send the stream of bolometric measurements in real time to the PC. In order to solve the cross-talk between the bridges and the cables, each of the four bridges in the bolometer head receives a different synthesized excitation frequency. Since the system is fully controlled by a PC GUI (Graphic User Interface), it is very user friendly. Moreover, some useful features have been developed, such as: auto off-set correction, bridge amplitude regulation, software gain setting, real time visualization, frequency excitation selection and noise spectrum analyzer embedded function. In this paper, the

  20. Neuromimetic Circuits with Synaptic Devices Based on Strongly Correlated Electron Systems

    Science.gov (United States)

    Ha, Sieu D.; Shi, Jian; Meroz, Yasmine; Mahadevan, L.; Ramanathan, Shriram

    2014-12-01

    Strongly correlated electron systems such as the rare-earth nickelates (R NiO3 , R denotes a rare-earth element) can exhibit synapselike continuous long-term potentiation and depression when gated with ionic liquids; exploiting the extreme sensitivity of coupled charge, spin, orbital, and lattice degrees of freedom to stoichiometry. We present experimental real-time, device-level classical conditioning and unlearning using nickelate-based synaptic devices in an electronic circuit compatible with both excitatory and inhibitory neurons. We establish a physical model for the device behavior based on electric-field-driven coupled ionic-electronic diffusion that can be utilized for design of more complex systems. We use the model to simulate a variety of associate and nonassociative learning mechanisms, as well as a feedforward recurrent network for storing memory. Our circuit intuitively parallels biological neural architectures, and it can be readily generalized to other forms of cellular learning and extinction. The simulation of neural function with electronic device analogs may provide insight into biological processes such as decision making, learning, and adaptation, while facilitating advanced parallel information processing in hardware.

  1. Flocking from a quantum analogy: spin-orbit coupling in an active fluid

    Science.gov (United States)

    Loewe, Benjamin; Souslov, Anton; Goldbart, Paul M.

    2018-01-01

    Systems composed of strongly interacting self-propelled particles can form a spontaneously flowing polar active fluid. The study of the connection between the microscopic dynamics of a single such particle and the macroscopic dynamics of the fluid can yield insights into experimentally realizable active flows, but this connection is well understood in only a few select cases. We introduce a model of self-propelled particles based on an analogy with the motion of electrons that have strong spin-orbit coupling. We find that, within our model, self-propelled particles are subject to an analog of the Heisenberg uncertainty principle that relates translational and rotational noise. Furthermore, by coarse-graining this microscopic model, we establish expressions for the coefficients of the Toner-Tu equations—the hydrodynamic equations that describe an active fluid composed of these ‘active spins.’ The connection between stochastic self-propelled particles and quantum particles with spin may help realize exotic phases of matter using active fluids via analogies with systems composed of strongly correlated electrons.

  2. Planning the electron traffic in semiconductor networks: A mesoscopic analog of the Braess paradox encountered in road networks

    International Nuclear Information System (INIS)

    Huant, S.; Liu, P.; Sellier, H.; Baltazar, S.; Hackens, B.; Martins, F.; Bayot, V.; Wallart, X.; Desplanque, L.; Pala, M. G.

    2013-01-01

    By combining quantum simulations of electron transport and scanning-gate microscopy, we have shown that the current transmitted through a semiconductor two-path rectangular network in the ballistic and coherent regimes of transport can be paradoxically degraded by adding a third path to the network. This is analogous to the Braess paradox occurring in classical networks. Simulations reported here enlighten the role played by congestion in the network

  3. Electronically Tunable Transimpedance Instrumentation Amplifier Based on OTRA

    Directory of Open Access Journals (Sweden)

    Rajeshwari Pandey

    2013-01-01

    Full Text Available Operational transresistance amplifier (OTRA is the most suitable analog building block (ABB for transimpedance type signal processing due to its very nature of current input and voltage output. In this paper, OTRA-based transimpedance instrumentation amplifier (TIA is presented. It provides high differential gain and bandwidth, which is independent of gain. It also offers high common-mode rejection ratio (CMRR. The amplifier gain can be controlled electronically by implementing resistors using MOS transistors operating in linear region. The circuit can be made fully integrated. The proposed circuit is insensitive to parasitic input capacitances and input resistances due to the internally grounded input terminals of OTRA. Theoretical analysis is verified through PSPICE simulations and experimentation.

  4. Teleseism-based Relative Time Corrections for Modern Analyses of Digitized Analog Seismograms

    Science.gov (United States)

    Lee, T. A.; Ishii, M.

    2017-12-01

    With modern-day instruments and seismic networks timed by GPS systems, synchronization of data streams is all but a forgone conclusion. However, during the analog era, when each station had its own clock, comparing data timing from different stations was a far more daunting prospect. Today, with recently developed methods by which analog data can be digitized, having the ability to accurately reconcile the timings of two separate stations would open decades worth of data to modern analyses. For example, one possible and exciting application would be using noise interferometry with digitized analog data in order to investigate changing structural features (on a volcano for example) over a much longer timescale than was previously possible. With this in mind, we introduce a new approach to sync time between stations based on teleseismic arrivals. P-wave arrivals are identified at stations for pairs of earthquakes from the digital and analog eras that have nearly identical distances, locations, and depths. Assuming accurate timing of the modern data, relative time corrections between a pair of stations can then be inferred for the analog data. This method for time correction depends upon the analog stations having modern equivalents, and both having sufficiently long durations of operation to allow for recording of usable teleseismic events. The Hawaii Volcano Observatory (HVO) network is an especially ideal environment for this, as it not only has a large and well-preserved collection of analog seismograms, but also has a long operating history (1912 - present) with many of the older stations having modern equivalents. As such, the scope of this project is to calculate and apply relative time corrections to analog data from two HVO stations, HILB (1919-present) and UWE (1928-present)(HILB now part of Pacific Tsunami network). Further application of this method could be for investigation of the effects of relative clock-drift, that is, the determining factor for how

  5. NASA Software Cost Estimation Model: An Analogy Based Estimation Model

    Science.gov (United States)

    Hihn, Jairus; Juster, Leora; Menzies, Tim; Mathew, George; Johnson, James

    2015-01-01

    The cost estimation of software development activities is increasingly critical for large scale integrated projects such as those at DOD and NASA especially as the software systems become larger and more complex. As an example MSL (Mars Scientific Laboratory) developed at the Jet Propulsion Laboratory launched with over 2 million lines of code making it the largest robotic spacecraft ever flown (Based on the size of the software). Software development activities are also notorious for their cost growth, with NASA flight software averaging over 50% cost growth. All across the agency, estimators and analysts are increasingly being tasked to develop reliable cost estimates in support of program planning and execution. While there has been extensive work on improving parametric methods there is very little focus on the use of models based on analogy and clustering algorithms. In this paper we summarize our findings on effort/cost model estimation and model development based on ten years of software effort estimation research using data mining and machine learning methods to develop estimation models based on analogy and clustering. The NASA Software Cost Model performance is evaluated by comparing it to COCOMO II, linear regression, and K-­ nearest neighbor prediction model performance on the same data set.

  6. Analog fourier transform channelizer and OFDM receiver

    OpenAIRE

    2007-01-01

    An OFDM receiver having an analog multiplier based I-Q channelizing filter, samples and holds consecutive analog I-Q samples of an I-Q baseband, the I-Q basebands having OFDM sub-channels. A lattice of analog I-Q multipliers and analog I-Q summers concurrently receives the held analog I-Q samples, performs analog I-Q multiplications and analog I-Q additions to concurrently generate a plurality of analog I-Q output signals, representing an N-point discrete Fourier transform of the held analog ...

  7. Inductive, Analogical, and Communicative Generalization

    Directory of Open Access Journals (Sweden)

    Adri Smaling

    2003-03-01

    Full Text Available Three forms of inductive generalization - statistical generalization, variation-based generalization and theory-carried generalization - are insufficient concerning case-to-case generalization, which is a form of analogical generalization. The quality of case-to-case generalization needs to be reinforced by setting up explicit analogical argumentation. To evaluate analogical argumentation six criteria are discussed. Good analogical reasoning is an indispensable support to forms of communicative generalization - receptive and responsive (participative generalization — as well as exemplary generalization.

  8. Analog integrated circuit design automation placement, routing and parasitic extraction techniques

    CERN Document Server

    Martins, Ricardo; Horta, Nuno

    2017-01-01

    This book introduces readers to a variety of tools for analog layout design automation. After discussing the placement and routing problem in electronic design automation (EDA), the authors overview a variety of automatic layout generation tools, as well as the most recent advances in analog layout-aware circuit sizing. The discussion includes different methods for automatic placement (a template-based Placer and an optimization-based Placer), a fully-automatic Router and an empirical-based Parasitic Extractor. The concepts and algorithms of all the modules are thoroughly described, enabling readers to reproduce the methodologies, improve the quality of their designs, or use them as starting point for a new tool. All the methods described are applied to practical examples for a 130nm design process, as well as placement and routing benchmark sets. Introduces readers to hierarchical combination of Pareto fronts of placements; Presents electromigration-aware routing with multilayer multiport terminal structures...

  9. Design rules for superconducting analog-digital transducers; Entwurfsregeln fuer Supraleitende Analog-Digital-Wandler

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, Taghrid

    2015-05-29

    This Thesis is a contribution for dimensioning aspects of circuits designs in superconductor electronics. Mainly superconductor comparators inclusive Josephson comparators as well as QOJS-Comparators are investigated. Both types were investigated in terms of speed and sensitivity. The influence of the thermal noise on the decision process of the comparators represent in so called gray zone, which is analysed in this thesis. Thereby, different relations between design parameters were derived. A circuit model of the Josephson comparator was verified by experiments. Concepts of superconductor analog-to-digital converters, which are based on above called comparators, were investigated in detail. From the comparator design rules, new rules for AD-converters were derived. Because of the reduced switching energy, the signal to noise ratio (SNR) of the circuits is affected and therefore the reliability of the decision-process is affected. For special applications with very demanding requirements in terms of the speed and accuracy superconductor analog-to-digital converters offer an excellent performance. This thesis provides relations between different design paramenters and shows resulting trade-offs, This method is transparent and easy to transfer to other circuit topologies. As a main result, a highly predictive tool for dimensioning of superconducting ADC's is proved.

  10. High-performance electronics for time-of-flight PET systems

    International Nuclear Information System (INIS)

    Choong, W-S; Peng, Q; Vu, C Q; Turko, B T; Moses, W W

    2013-01-01

    We have designed and built a high-performance readout electronics system for time-of-flight positron emission tomography (TOF PET) cameras. The electronics architecture is based on the electronics for a commercial whole-body PET camera (Siemens/CPS Cardinal electronics), modified to improve the timing performance. The fundamental contributions in the electronics that can limit the timing resolution include the constant fraction discriminator (CFD), which converts the analog electrical signal from the photo-detector to a digital signal whose leading edge is time-correlated with the input signal, and the time-to-digital converter (TDC), which provides a time stamp for the CFD output. Coincident events are identified by digitally comparing the values of the time stamps. In the Cardinal electronics, the front-end processing electronics are performed by an Analog subsection board, which has two application-specific integrated circuits (ASICs), each servicing a PET block detector module. The ASIC has a built-in CFD and TDC. We found that a significant degradation in the timing resolution comes from the ASIC's CFD and TDC. Therefore, we have designed and built an improved Analog subsection board that replaces the ASIC's CFD and TDC with a high-performance CFD (made with discrete components) and TDC (using the CERN high-performance TDC ASIC). The improved Analog subsection board is used in a custom single-ring LSO-based TOF PET camera. The electronics system achieves a timing resolution of 60 ps FWHM. Prototype TOF detector modules are read out with the electronics system and give coincidence timing resolutions of 259 ps FWHM and 156 ps FWHM for detector modules coupled to LSO and LaBr 3 crystals respectively.

  11. Diagnosis of soft faults in analog integrated circuits based on fractional correlation

    International Nuclear Information System (INIS)

    Deng Yong; Shi Yibing; Zhang Wei

    2012-01-01

    Aiming at the problem of diagnosing soft faults in analog integrated circuits, an approach based on fractional correlation is proposed. First, the Volterra series of the circuit under test (CUT) decomposed by the fractional wavelet packet are used to calculate the fractional correlation functions. Then, the calculated fractional correlation functions are used to form the fault signatures of the CUT. By comparing the fault signatures, the different soft faulty conditions of the CUT are identified and the faults are located. Simulations of benchmark circuits illustrate the proposed method and validate its effectiveness in diagnosing soft faults in analog integrated circuits. (semiconductor integrated circuits)

  12. Producing and Recognizing Analogical Relations

    Science.gov (United States)

    Lipkens, Regina; Hayes, Steven C

    2009-01-01

    Analogical reasoning is an important component of intelligent behavior, and a key test of any approach to human language and cognition. Only a limited amount of empirical work has been conducted from a behavior analytic point of view, most of that within Relational Frame Theory (RFT), which views analogy as a matter of deriving relations among relations. The present series of four studies expands previous work by exploring the applicability of this model of analogy to topography-based rather than merely selection-based responses and by extending the work into additional relations, including nonsymmetrical ones. In each of the four studies participants pretrained in contextual control over nonarbitrary stimulus relations of sameness and opposition, or of sameness, smaller than, and larger than, learned arbitrary stimulus relations in the presence of these relational cues and derived analogies involving directly trained relations and derived relations of mutual and combinatorial entailment, measured using a variety of productive and selection-based measures. In Experiment 1 participants successfully recognized analogies among stimulus networks containing same and opposite relations; in Experiment 2 analogy was successfully used to extend derived relations to pairs of novel stimuli; in Experiment 3 the procedure used in Experiment 1 was extended to nonsymmetrical comparative relations; in Experiment 4 the procedure used in Experiment 2 was extended to nonsymmetrical comparative relations. Although not every participant showed the effects predicted, overall the procedures occasioned relational responses consistent with an RFT account that have not yet been demonstrated in a behavior-analytic laboratory setting, including productive responding on the basis of analogies. PMID:19230515

  13. Introduction to engineering a starter's guide with hands-on analog multimedia explorations

    CERN Document Server

    Karam, Lina

    2008-01-01

    This lecture provides a hands-on glimpse of the field of electrical engineering. The introduced applications utilize the NI ELVIS hardware and software platform to explore concepts such as circuits, power, analog sensing, and introductory analog signal processing such as signal generation, analog filtering, and audio and music processing. These principals and technologies are introduced in a very practical way and are fundamental to many of the electronic devices we use today. Some examples include photodetection, analog signal (audio, light, temperature) level meter, and analog music equalize

  14. Digital circuit for the introduction and later removal of dither from an analog signal

    Science.gov (United States)

    Borgen, Gary S.

    1994-05-01

    An electronics circuit is presented for accurately digitizing an analog audio or like data signal into a digital equivalent signal by introducing dither into the analog signal and then subsequently removing the dither from the digitized signal prior to its conversion to an analog signal which is a substantial replica of the incoming analog audio or like data signal. The electronics circuit of the present invention is characterized by a first pseudo-random number generator which generates digital random noise signals or dither for addition to the digital equivalent signal and a second pseudo-random number generator which generates subtractive digital random noise signals for the subsequent removal of dither from the digital equivalent signal prior its conversion to the analog replica signal.

  15. A Loudness Function for Analog and Digital Sound Systems based on Equal Loudness Level Contours

    DEFF Research Database (Denmark)

    Nielsen, Sofus Birkedal

    2016-01-01

    frequency balance will been changed both for LL lower or higher than ML. The differences in ELLC ask for a level based equalization using fractional-order filters. A designing technique for both analog and digital fractional-order filters was developed. The analog solution is based on OPAMs and the digital......A new and better loudness compensation has been designed based on the differences between the Equal Loudness Level Contours (ELLC) in ISO 226:2003. Sound productions are normally being mixed at a high mixing level (ML) but often played at lower listening level (LL) which mean that the perceived...

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

    Science.gov (United States)

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

    2017-09-01

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

  17. System-level techniques for analog performance enhancement

    CERN Document Server

    Song, Bang-Sup

    2016-01-01

    This book shows readers to avoid common mistakes in circuit design, and presents classic circuit concepts and design approaches from the transistor to the system levels. The discussion is geared to be accessible and optimized for practical designers who want to learn to create circuits without simulations. Topic by topic, the author guides designers to learn the classic analog design skills by understanding the basic electronics principles correctly, and further prepares them to feel confident in designing high-performance, state-of-the art CMOS analog systems. This book combines and presents all in-depth necessary information to perform various design tasks so that readers can grasp essential material, without reading through the entire book. This top-down approach helps readers to build practical design expertise quickly, starting from their understanding of electronics fundamentals. .

  18. The Use of a Solid State Analog Television Transmitter as a Superconducting Electron Gun Power Amplifier

    Energy Technology Data Exchange (ETDEWEB)

    J.G. Kulpin, K.J. Kleman, R.A. Legg

    2012-07-01

    A solid state analog television transmitter designed for 200 MHz operation is being commissioned as a radio frequency power amplifier on the Wisconsin superconducting electron gun cavity. The amplifier consists of three separate radio frequency power combiner cabinets and one monitor and control cabinet. The transmitter employs rugged field effect transistors built into one kilowatt drawers that are individually hot swappable at maximum continuous power output. The total combined power of the transmitter system is 33 kW at 200 MHz, output through a standard coaxial transmission line. A low level radio frequency system is employed to digitally synthesize the 200 MHz signal and precisely control amplitude and phase.

  19. A language based on analogy to communicate cultural concepts in SETI

    Science.gov (United States)

    Musso, Paolo

    2011-02-01

    The present paper is a synthesis of three presentation given by myself at the Toulouse IAC 2001 ( Analogy as a tool to communicate abstract concepts in SETI), the Bremen IAC 2003 ( From maths to culture: towards an effective message), and the Vancouver IAC 2004 ( Philosophical and religious implications of extraterrestrial intelligent life). Its aim is to find a way to make our cultural concepts understandable to hypothetical extraterrestrials (ETs) in a SETI communication. First of all, I expose the reasons why I think that analogy could be a good tool for this purpose. Then, I try to show that this is possible only in the context of an integrated language, using both abstract symbols and pictures, also sketching two practical examples about some basic concepts of our moral and religious tradition. Further studies are required to determine whether this method could be extended to the higher-level abstract concepts in the other fields of our culture. Finally, I discuss the possible role of mathematics, logic and natural science in the construction of an analogy-based language for interstellar messages with a cultural content and a possible way of managing this matter from a social point of view.

  20. The front-end analog and digital signal processing electronics for the drift chambers of the Stanford Large Detector

    International Nuclear Information System (INIS)

    Haller, G.M.; Freytag, D.R.; Fox, J.; Olsen, J.; Paffrath, L.; Yim, A.; Honma, A.

    1990-10-01

    The front-end signal processing electronics for the drift-chambers of the Stanford Large Detector (SLD) at the Stanford Linear Collider is described. The system is implemented with printed-circuit boards which are shaped for direct mounting on the detector. Typically, a motherboard comprises 64 channels of transimpedance amplification and analog waveform sampling, A/D conversion, and associated control and readout circuitry. The loaded motherboard thus forms a processor which records low-level wave forms from 64 detector channels and transforms the information into a 64 k-byte serial data stream. In addition, the package performs calibration functions, measures leakage currents on the wires, and generates wire hit patterns for triggering purposes. The construction and operation of the electronic circuits utilizing monolithic, hybridized, and programmable components are discussed

  1. Doubling-resolution analog-to-digital conversion based on PIC18F45K80

    Directory of Open Access Journals (Sweden)

    Yueyang Yuan

    2014-08-01

    Full Text Available Aiming at the analog signal being converted into the digital with a higher precision, a method to improve the analog-to-digital converter (ADC resolution is proposed and described. Based on the microcomputer PIC18F45K80 in which the internal ADC modules are embedded, a circuit is designed for doubling the resolution of ADC. According to the circuit diagram, the mathematical formula for calculating this resolution is derived. The corresponding software and print circuit board assembly is also prepared. With the experiment, a 13 bit ADC is achieved based on the 12 bit ADC module predesigned in the PIC18F45K80.

  2. Quantum walks based on an interferometric analogy

    International Nuclear Information System (INIS)

    Hillery, Mark; Bergou, Janos; Feldman, Edgar

    2003-01-01

    There are presently two models for quantum walks on graphs. The ''coined'' walk uses discrete-time steps, and contains, besides the particle making the walk, a second quantum system, the coin, that determines the direction in which the particle will move. The continuous walk operates with continuous time. Here a third model for quantum walks is proposed, which is based on an analogy to optical interferometers. It is a discrete-time model, and the unitary operator that advances the walk one step depends only on the local structure of the graph on which the walk is taking place. This type of walk also allows us to introduce elements, such as phase shifters, that have no counterpart in classical random walks. Several examples are discussed

  3. Analog voicing detector responds to pitch

    Science.gov (United States)

    Abel, R. S.; Watkins, H. E.

    1967-01-01

    Modified electronic voice encoder /Vocoder/ includes an independent analog mode of operation in addition to the conventional digital mode. The Vocoder is a bandwidth compression equipment that permits voice transmission over channels, having only a fraction of the bandwidth required for conventional telephone-quality speech transmission.

  4. Detecting analogical resemblance without retrieving the source analogy.

    Science.gov (United States)

    Kostic, Bogdan; Cleary, Anne M; Severin, Kaye; Miller, Samuel W

    2010-06-01

    We examined whether people can detect analogical resemblance to an earlier experimental episode without being able to recall the experimental source of the analogical resemblance. We used four-word analogies (e.g., robin-nest/beaver-dam), in a variation of the recognition-without-cued-recall method (Cleary, 2004). Participants studied word pairs (e.g., robin-nest) and were shown new word pairs at test, half of which analogically related to studied word pairs (e.g., beaver-dam) and half of which did not. For each test pair, participants first attempted to recall an analogically similar pair from the study list. Then, regardless of whether successful recall occurred, participants were prompted to rate the familiarity of the test pair, which was said to indicate the likelihood that a pair that was analogically similar to the test pair had been studied. Across three experiments, participants demonstrated an ability to detect analogical resemblance without recalling the source analogy. Findings are discussed in terms of their potential relevance to the study of analogical reasoning and insight, as well as to the study of familiarity and recognition memory.

  5. Controller for control of pulsed electron linear accelerator

    International Nuclear Information System (INIS)

    Bryazgin, A.A.; Faktorovich, B.L.

    1995-01-01

    The controller is based on the K1816VE31 microprocessor and contains 22-channel integrating 10-digital two-wire analog-to-digital converter, 8-channel 12-digit digital-to-analog converter, 24-digit output register, 16-digit input register pulse generator in the range of 0.5 - 50 Hz with the regulation step of 0.05 Hz and delayed pulse generator. The controller is used for pulsed electron linear accelerator control and is reduced to regulation of the electron beam pulse repetition rate and beam energy. 1 ref., 1 fig

  6. Readout electronic for multichannel detectors

    CERN Document Server

    Kulibaba, V I; Naumov, S V

    2001-01-01

    Readout electronics based on the 128-channel chip 'Viking' (IDE AS inc., Norway) is considered. The chip 'Viking' integrates 128 low noise charge-sensitive preamplifiers with tunable CR-(RC) sup 2 shapers,analog memory and multiplexed readout to one output. All modules of readout electronics were designed and produced in KIPT taking into account the published recommendations of IDE AS inc.

  7. Readout electronic for multichannel detectors

    International Nuclear Information System (INIS)

    Kulibaba, V.I.; Maslov, N.I.; Naumov, S.V.

    2001-01-01

    Readout electronics based on the 128-channel chip 'Viking' (IDE AS inc., Norway) is considered. The chip 'Viking' integrates 128 low noise charge-sensitive preamplifiers with tunable CR-(RC) 2 shapers,analog memory and multiplexed readout to one output. All modules of readout electronics were designed and produced in KIPT taking into account the published recommendations of IDE AS inc

  8. Carbon nanotube transistor based high-frequency electronics

    Science.gov (United States)

    Schroter, Michael

    At the nanoscale carbon nanotubes (CNTs) have higher carrier mobility and carrier velocity than most incumbent semiconductors. Thus CNT based field-effect transistors (FETs) are being considered as strong candidates for replacing existing MOSFETs in digital applications. In addition, the predicted high intrinsic transit frequency and the more recent finding of ways to achieve highly linear transfer characteristics have inspired investigations on analog high-frequency (HF) applications. High linearity is extremely valuable for an energy efficient usage of the frequency spectrum, particularly in mobile communications. Compared to digital applications, the much more relaxed constraints for CNT placement and lithography combined with already achieved operating frequencies of at least 10 GHz for fabricated devices make an early entry in the low GHz HF market more feasible than in large-scale digital circuits. Such a market entry would be extremely beneficial for funding the development of production CNTFET based process technology. This talk will provide an overview on the present status and feasibility of HF CNTFET technology will be given from an engineering point of view, including device modeling, experimental results, and existing roadblocks. Carbon nanotube transistor based high-frequency electronics.

  9. A simple method to adapt time sampling of the analog signal

    International Nuclear Information System (INIS)

    Kalinin, Yu.G.; Martyanov, I.S.; Sadykov, Kh.; Zastrozhnova, N.N.

    2004-01-01

    In this paper we briefly describe the time sampling method, which is adapted to the speed of the signal change. Principally, this method is based on a simple idea--the combination of discrete integration with differentiation of the analog signal. This method can be used in nuclear electronics research into the characteristics of detectors and the shape of the pulse signal, pulse and transitive characteristics of inertial systems of processing of signals, etc

  10. Fiber optic analog and timing monitoring system for the antares laser fusion program

    International Nuclear Information System (INIS)

    Longmire, J.L.; Thuot, M.E.

    1981-01-01

    The development and use of two optical fiber systems for the Antares 40 kJ CO 2 laser is described. In the Antares power amplifier, electron guns produce a discharge-sustaining B kA beam of 500 kV electrons. Eight 300 kJ, 3 μs Marx pulsers provide a direct electrical pumping discharge through the laser gas. The electro-optic systems developed allow the measurement of pulsed analog waveforms and trigger timing information within the laser and power systems by a computer based control and data acquisition network

  11. Electronics and electronic systems

    CERN Document Server

    Olsen, George H

    1987-01-01

    Electronics and Electronic Systems explores the significant developments in the field of electronics and electronic devices. This book is organized into three parts encompassing 11 chapters that discuss the fundamental circuit theory and the principles of analog and digital electronics. This book deals first with the passive components of electronic systems, such as resistors, capacitors, and inductors. These topics are followed by a discussion on the analysis of electronic circuits, which involves three ways, namely, the actual circuit, graphical techniques, and rule of thumb. The remaining p

  12. On-line control system for electron injector based on autoemission cathode

    International Nuclear Information System (INIS)

    Egorov, N.V.; Karpov, A.G.; Ovsyannikov, D.A.; Prudnikov, A.P.

    1987-01-01

    An original on-line system of control of electron injector parameters on the base of an autoemission cathode is described. The system includes hardware (analog-to-digital and graphical displays, a printer, a magnetic disc memory a plotter) and data control and readout equipment. A high-voltage power source of the 'RACE' is controlled by digital measuring devices connected with a computer data via a special matching device. Software includes servicing subroutines for injector controls and those permitting to display, plot and print results. The main operating program functioning in the interactive mode enables to specify the injector operating conditions and check its characteristics

  13. Unity and disunity in evolutionary sciences: process-based analogies open common research avenues for biology and linguistics.

    Science.gov (United States)

    List, Johann-Mattis; Pathmanathan, Jananan Sylvestre; Lopez, Philippe; Bapteste, Eric

    2016-08-20

    For a long time biologists and linguists have been noticing surprising similarities between the evolution of life forms and languages. Most of the proposed analogies have been rejected. Some, however, have persisted, and some even turned out to be fruitful, inspiring the transfer of methods and models between biology and linguistics up to today. Most proposed analogies were based on a comparison of the research objects rather than the processes that shaped their evolution. Focusing on process-based analogies, however, has the advantage of minimizing the risk of overstating similarities, while at the same time reflecting the common strategy to use processes to explain the evolution of complexity in both fields. We compared important evolutionary processes in biology and linguistics and identified processes specific to only one of the two disciplines as well as processes which seem to be analogous, potentially reflecting core evolutionary processes. These new process-based analogies support novel methodological transfer, expanding the application range of biological methods to the field of historical linguistics. We illustrate this by showing (i) how methods dealing with incomplete lineage sorting offer an introgression-free framework to analyze highly mosaic word distributions across languages; (ii) how sequence similarity networks can be used to identify composite and borrowed words across different languages; (iii) how research on partial homology can inspire new methods and models in both fields; and (iv) how constructive neutral evolution provides an original framework for analyzing convergent evolution in languages resulting from common descent (Sapir's drift). Apart from new analogies between evolutionary processes, we also identified processes which are specific to either biology or linguistics. This shows that general evolution cannot be studied from within one discipline alone. In order to get a full picture of evolution, biologists and linguists need to

  14. Digitalization and networking of analog simulators and portal images.

    Science.gov (United States)

    Pesznyák, Csilla; Zaránd, Pál; Mayer, Arpád

    2007-03-01

    Many departments have analog simulators and irradiation facilities (especially cobalt units) without electronic portal imaging. Import of the images into the R&V (Record & Verify) system is required. Simulator images are grabbed while portal films scanned by using a laser scanner and both converted into DICOM RT (Digital Imaging and Communications in Medicine Radiotherapy) images. Image intensifier output of a simulator and portal films are converted to DICOM RT images and used in clinical practice. The simulator software was developed in cooperation at the authors' hospital. The digitalization of analog simulators is a valuable updating in clinical use replacing screen-film technique. Film scanning and digitalization permit the electronic archiving of films. Conversion into DICOM RT images is a precondition of importing to the R&V system.

  15. Associative memory in an analog iterated-map neural network

    Science.gov (United States)

    Marcus, C. M.; Waugh, F. R.; Westervelt, R. M.

    1990-03-01

    The behavior of an analog neural network with parallel dynamics is studied analytically and numerically for two associative-memory learning algorithms, the Hebb rule and the pseudoinverse rule. Phase diagrams in the parameter space of analog gain β and storage ratio α are presented. For both learning rules, the networks have large ``recall'' phases in which retrieval states exist and convergence to a fixed point is guaranteed by a global stability criterion. We also demonstrate numerically that using a reduced analog gain increases the probability of recall starting from a random initial state. This phenomenon is comparable to thermal annealing used to escape local minima but has the advantage of being deterministic, and therefore easily implemented in electronic hardware. Similarities and differences between analog neural networks and networks with two-state neurons at finite temperature are also discussed.

  16. Genome-wide screening for genes whose deletions confer sensitivity to mutagenic purine base analogs in yeast

    Directory of Open Access Journals (Sweden)

    Kozmin Stanislav G

    2005-06-01

    Full Text Available Abstract Background N-hydroxylated base analogs, such as 6-hydroxylaminopurine (HAP and 2-amino-6-hydroxylaminopurine (AHA, are strong mutagens in various organisms due to their ambiguous base-pairing properties. The systems protecting cells from HAP and related noncanonical purines in Escherichia coli include specialized deoxyribonucleoside triphosphatase RdgB, DNA repair endonuclease V, and a molybdenum cofactor-dependent system. Fewer HAP-detoxification systems have been identified in yeast Saccharomyces cerevisiae and other eukaryotes. Cellular systems protecting from AHA are unknown. In the present study, we performed a genome-wide search for genes whose deletions confer sensitivity to HAP and AHA in yeast. Results We screened the library of yeast deletion mutants for sensitivity to the toxic and mutagenic action of HAP and AHA. We identified novel genes involved in the genetic control of base analogs sensitivity, including genes controlling purine metabolism, cytoskeleton organization, and amino acid metabolism. Conclusion We developed a method for screening the yeast deletion library for sensitivity to the mutagenic and toxic action of base analogs and identified 16 novel genes controlling pathways of protection from HAP. Three of them also protect from AHA.

  17. Analogical scaffolding: Making meaning in physics through representation and analogy

    Science.gov (United States)

    Podolefsky, Noah Solomon

    This work reviews the literature on analogy, introduces a new model of analogy, and presents a series of experiments that test and confirm the utility of this model to describe and predict student learning in physics with analogy. Pilot studies demonstrate that representations (e.g., diagrams) can play a key role in students' use of analogy. A new model of analogy, Analogical Scaffolding, is developed to explain these initial empirical results. This model will be described in detail, and then applied to describe and predict the outcomes of further experiments. Two large-scale (N>100) studies will demonstrate that: (1) students taught with analogies, according to the Analogical Scaffolding model, outperform students taught without analogies on pre-post assessments focused on electromagnetic waves; (2) the representational forms used to teach with analogy can play a significant role in student learning, with students in one treatment group outperforming students in other treatment groups by factors of two or three. It will be demonstrated that Analogical Scaffolding can be used to predict these results, as well as finer-grained results such as the types of distracters students choose in different treatment groups, and to describe and analyze student reasoning in interviews. Abstraction in physics is reconsidered using Analogical Scaffolding. An operational definition of abstraction is developed within the Analogical Scaffolding framework and employed to explain (a) why physicists consider some ideas more abstract than others in physics, and (b) how students conceptions of these ideas can be modeled. This new approach to abstraction suggests novel approaches to curriculum design in physics using Analogical Scaffolding.

  18. 23rd workshop on Advances in Analog Circuit Design

    CERN Document Server

    Baschirotto, Andrea; Makinwa, Kofi

    2015-01-01

    This book is based on the 18 tutorials presented during the 23rd workshop on Advances in Analog Circuit Design.  Expert designers present readers with information about a variety of topics at the frontier of analog circuit design, serving as a valuable reference to the state-of-the-art, for anyone involved in analog circuit research and development.    • Includes coverage of high-performance analog-to-digital and digital to analog converters, integrated circuit design in scaled technologies, and time-domain signal processing; • Provides a state-of-the-art reference in analog circuit design, written by experts from industry and academia; • Presents material in a tutorial-based format.

  19. Computational approaches to analogical reasoning current trends

    CERN Document Server

    Richard, Gilles

    2014-01-01

    Analogical reasoning is known as a powerful mode for drawing plausible conclusions and solving problems. It has been the topic of a huge number of works by philosophers, anthropologists, linguists, psychologists, and computer scientists. As such, it has been early studied in artificial intelligence, with a particular renewal of interest in the last decade. The present volume provides a structured view of current research trends on computational approaches to analogical reasoning. It starts with an overview of the field, with an extensive bibliography. The 14 collected contributions cover a large scope of issues. First, the use of analogical proportions and analogies is explained and discussed in various natural language processing problems, as well as in automated deduction. Then, different formal frameworks for handling analogies are presented, dealing with case-based reasoning, heuristic-driven theory projection, commonsense reasoning about incomplete rule bases, logical proportions induced by similarity an...

  20. Fast multichannel analog storage system

    International Nuclear Information System (INIS)

    Freytag, D.R.

    1982-11-01

    A Multichannel Analog Storage System based on a commercial 32-channel parallel in/serial out (PISO) analog shift register is described. The basic unit is a single width CAMAC module containing 512 analog cells and the associated logic for data storage and subsequent readout. At sampling rates of up to 30 MHz the signals are strobed directly into the PISO. At higher rates signals are strobed into a fast presampling stage and subsequently transferred in block form into an array of PISO's. Sampling rates of 300 MHz have been achieved with the present device and 1000 MHz are possible with improved signal drivers. The system is well suited for simultaneous handling of many signal channels with moderate numbers of samples in each channel. RMS noise over full scale signal has been measured as 1:3000 (approx. = 11 bit). However, nonlinearities in the response and differences in sensitivity of the analog cells require an elaborate calibration system in order to realize 11 bit accuracy for the analog information

  1. Low-voltage analog front-end processor design for ISFET-based sensor and H+ sensing applications

    Science.gov (United States)

    Chung, Wen-Yaw; Yang, Chung-Huang; Peng, Kang-Chu; Yeh, M. H.

    2003-04-01

    This paper presents a modular-based low-voltage analog-front-end processor design in a 0.5mm double-poly double-metal CMOS technology for Ion Sensitive Field Effect Transistor (ISFET)-based sensor and H+ sensing applications. To meet the potentiometric response of the ISFET that is proportional to various H+ concentrations, the constant-voltage and constant current (CVCS) testing configuration has been used. Low-voltage design skills such as bulk-driven input pair, folded-cascode amplifier, bootstrap switch control circuits have been designed and integrated for 1.5V supply and nearly rail-to-rail analog to digital signal processing. Core modules consist of an 8-bit two-step analog-digital converter and bulk-driven pre-amplifiers have been developed in this research. The experimental results show that the proposed circuitry has an acceptable linearity to 0.1 pH-H+ sensing conversions with the buffer solution in the range of pH2 to pH12. The processor has a potential usage in battery-operated and portable healthcare devices and environmental monitoring applications.

  2. Analogical proportions: another logical view

    Science.gov (United States)

    Prade, Henri; Richard, Gilles

    This paper investigates the logical formalization of a restricted form of analogical reasoning based on analogical proportions, i.e. statements of the form a is to b as c is to d. Starting from a naive set theoretic interpretation, we highlight the existence of two noticeable companion proportions: one states that a is to b the converse of what c is to d (reverse analogy), while the other called paralogical proportion expresses that what a and b have in common, c and d have it also. We identify the characteristic postulates of the three types of proportions and examine their consequences from an abstract viewpoint. We further study the properties of the set theoretic interpretation and of the Boolean logic interpretation, and we provide another light on the understanding of the role of permutations in the modeling of the three types of proportions. Finally, we address the use of these proportions as a basis for inference in a propositional setting, and relate it to more general schemes of analogical reasoning. The differences between analogy, reverse-analogy, and paralogy is still emphasized in a three-valued setting, which is also briefly presented.

  3. Priming analogical reasoning with false memories.

    Science.gov (United States)

    Howe, Mark L; Garner, Sarah R; Threadgold, Emma; Ball, Linden J

    2015-08-01

    Like true memories, false memories are capable of priming answers to insight-based problems. Recent research has attempted to extend this paradigm to more advanced problem-solving tasks, including those involving verbal analogical reasoning. However, these experiments are constrained inasmuch as problem solutions could be generated via spreading activation mechanisms (much like false memories themselves) rather than using complex reasoning processes. In three experiments we examined false memory priming of complex analogical reasoning tasks in the absence of simple semantic associations. In Experiment 1, we demonstrated the robustness of false memory priming in analogical reasoning when backward associative strength among the problem terms was eliminated. In Experiments 2a and 2b, we extended these findings by demonstrating priming on newly created homonym analogies that can only be solved by inhibiting semantic associations within the analogy. Overall, the findings of the present experiments provide evidence that the efficacy of false memory priming extends to complex analogical reasoning problems.

  4. Detecting analogies unconsciously

    Directory of Open Access Journals (Sweden)

    Thomas Peter Reber

    2014-01-01

    Full Text Available Analogies may arise from the conscious detection of similarities between a present and a past situation. In this functional magnetic resonance imaging study, we tested whether young volunteers would detect analogies unconsciously between a current supraliminal (visible and a past subliminal (invisible situation. The subliminal encoding of the past situation precludes awareness of analogy detection in the current situation. First, participants encoded subliminal pairs of unrelated words in either one or nine encoding trials. Later, they judged the semantic fit of supraliminally presented new words that either retained a previously encoded semantic relation (‘analog’ or not (‘broken analog’. Words in analogs versus broken analogs were judged closer semantically, which reflects unconscious analogy detection. Hippocampal activity associated with subliminal encoding correlated with the behavioral measure of unconscious analogy detection. Analogs versus broken analogs were processed with reduced prefrontal but enhanced medial temporal activity. We conclude that analogous episodes can be detected even unconsciously drawing on the episodic memory network.

  5. Circuits and electronics hands-on learning with analog discovery

    CERN Document Server

    Okyere Attia, John

    2018-01-01

    The book provides instructions on building circuits on breadboards, connecting the Analog Discovery wires to the circuit under test, and making electrical measurements. Various measurement techniques are described and used in this book, including: impedance measurements, complex power measurements, frequency response measurements, power spectrum measurements, current versus voltage characteristic measurements of diodes, bipolar junction transistors, and Mosfets. The book includes end-of-chapter problems for additional exercises geared towards hands-on learning, experimentation, comparisons between measured results and those obtained from theoretical calculations.

  6. Resonant Tunneling Analog-To-Digital Converter

    Science.gov (United States)

    Broekaert, T. P. E.; Seabaugh, A. C.; Hellums, J.; Taddiken, A.; Tang, H.; Teng, J.; vanderWagt, J. P. A.

    1995-01-01

    As sampling rates continue to increase, current analog-to-digital converter (ADC) device technologies will soon reach a practical resolution limit. This limit will most profoundly effect satellite and military systems used, for example, for electronic countermeasures, electronic and signal intelligence, and phased array radar. New device and circuit concepts will be essential for continued progress. We describe a novel, folded architecture ADC which could enable a technological discontinuity in ADC performance. The converter technology is based on the integration of multiple resonant tunneling diodes (RTD) and hetero-junction transistors on an indium phosphide substrate. The RTD consists of a layered semiconductor hetero-structure AlAs/InGaAs/AlAs(2/4/2 nm) clad on either side by heavily doped InGaAs contact layers. Compact quantizers based around the RTD offer a reduction in the number of components and a reduction in the input capacitance Because the component count and capacitance scale with the number of bits N, rather than by 2 (exp n) as in the flash ADC, speed can be significantly increased, A 4-bit 2-GSps quantizer circuit is under development to evaluate the performance potential. Circuit designs for ADC conversion with a resolution of 6-bits at 25GSps may be enabled by the resonant tunneling approach.

  7. Event-Based Computation of Motion Flow on a Neuromorphic Analog Neural Platform

    Directory of Open Access Journals (Sweden)

    Massimiliano eGiulioni

    2016-02-01

    Full Text Available We demonstrate robust optical flow extraction with an analog neuromorphic multi-chip system. The task is performed by a feed-forward network of analog integrate-and-fire neurons whose inputs are provided by contrast-sensitive photoreceptors. Computation is supported by the precise time of spike emission and follows the basic theoretical principles presented in (Benosman et al. 2014: the extraction of the optical flow is based on time lag in the activation of nearby retinal neurons. The same basic principle is embedded in the architecture proposed by Barlow and Levick in 1965 to explain the spiking activity of the direction-selective ganglion cells in the rabbit's retina. Mimicking those cells our neuromorphic detectors encode the amplitude and the direction of the apparent visual motion in their output spiking pattern. We built a 3x3 test grid of independent detectors, each observing a different portion of the scene, so that our final output is a spike train encoding a 3x3 optical flow vector field. In this work we focus on the architectural aspects, and we demonstrate that a network of mismatched delicate analog elements can reliably extract the optical flow from a simple visual scene.

  8. Plasma generation and processing of interstellar carbonaceous dust analogs

    Science.gov (United States)

    Peláez, R. J.; Maté, B.; Tanarro, I.; Molpeceres, G.; Jiménez-Redondo, M.; Timón, V.; Escribano, R.; Herrero, V. J.

    2018-03-01

    Interstellar (IS) dust analogs, based on amorphous hydrogenated carbon (a-C:H) were generated by plasma deposition in radio frequency discharges of CH4 + He mixtures. The a-C:H samples were characterized by means of secondary electron microscopy, infrared (IR) spectroscopy and UV-visible reflectivity. DFT calculations of structure and IR spectra were also carried out. From the experimental data, atomic compositions were estimated. Both IR and reflectivity measurements led to similar high proportions (≈50%) of H atoms, but there was a significant discrepancy in the sp2/sp3 hybridization ratios of C atoms (sp2/sp3 = 1.5 from IR and 0.25 from reflectivity). Energetic processing of the samples with 5 keV electrons led to a decay of IR aliphatic bands and to a growth of aromatic bands, which is consistent with a dehydrogenation and graphitization of the samples. The decay of the CH aliphatic stretching band at 3.4 μm upon electron irradiation is relatively slow. Estimates based on the absorbed energy and on models of cosmic ray (CR) flux indicate that CR bombardment is not enough to justify the observed disappearance of this band in dense IS clouds.

  9. Neural correlates of creativity in analogical reasoning.

    Science.gov (United States)

    Green, Adam E; Kraemer, David J M; Fugelsang, Jonathan A; Gray, Jeremy R; Dunbar, Kevin N

    2012-03-01

    Brain-based evidence has implicated the frontal pole of the brain as important for analogical mapping. Separately, cognitive research has identified semantic distance as a key determinant of the creativity of analogical mapping (i.e., more distant analogies are generally more creative). Here, we used functional magnetic resonance imaging to assess brain activity during an analogy generation task in which we varied the semantic distance of analogical mapping (as derived quantitatively from a latent semantic analysis). Data indicated that activity within an a priori region of interest in left frontopolar cortex covaried parametrically with increasing semantic distance, even after removing effects of task difficulty. Results implicate increased recruitment of frontopolar cortex as a mechanism for integrating semantically distant information to generate solutions in creative analogical reasoning. 2012 APA, all rights reserved

  10. Automatic Generation of Analogy Questions for Student Assessment: An Ontology-Based Approach

    Science.gov (United States)

    Alsubait, Tahani; Parsia, Bijan; Sattler, Uli

    2012-01-01

    Different computational models for generating analogies of the form "A is to B as C is to D" have been proposed over the past 35 years. However, analogy generation is a challenging problem that requires further research. In this article, we present a new approach for generating analogies in Multiple Choice Question (MCQ) format that can be used…

  11. Bosonic analog of the Klein paradox

    International Nuclear Information System (INIS)

    Wagner, R. E.; Ware, M. R.; Su, Q.; Grobe, R.

    2010-01-01

    The standard Klein paradox describes how an incoming electron scatters off a supercritical electrostatic barrier that is so strong that it can generate electron-positron pairs. This fermionic system has been widely discussed in textbooks to illustrate some of the discrepancies between quantum mechanical and quantum field theoretical descriptions for the pair creation process. We compare the fermionic dynamics with that of the corresponding bosonic system. We point out that the direct counterpart of the Pauli exclusion principle (the central mechanism to resolve the fermionic Klein paradox) is stimulated emission, which leads to the resolution of the analogous bosonic paradox.

  12. How Analogy Drives Physics

    International Nuclear Information System (INIS)

    Hofstadter, Doug

    2004-01-01

    Many new ideas in theoretical physics come from analogies to older ideas in physics. For instance, the abstract notion of 'isospin' (or isotopic spin) originated in the prior concept of 'spin' (quantized angular momentum); likewise, the concept of 'phonon' (quantum of sound, or quantized collective excitation of a crystal) was based on the prior concept of 'photon' (quantum of light, or quantized element of the electromagnetic field). But these two examples, far from being exceptions, in fact represent the bread and butter of inventive thinking in physics. In a nutshell, intraphysics analogy-making -- borrowing by analogy with something already known in another area of physics -- is central to the progress of physics. The aim of this talk is to reveal the pervasiveness -- indeed, the indispensability -- of this kind of semi-irrational, wholly intuitive type of thinking (as opposed to more deductive mathematical inference) in the mental activity known as 'doing physics'. Speculations as to why wild analogical leaps are so crucial to the act of discovery in physics (as opposed to other disciplines) will be offered.

  13. Automatic activation of categorical and abstract analogical relations in analogical reasoning.

    Science.gov (United States)

    Green, Adam E; Fugelsang, Jonathan A; Dunbar, Kevin N

    2006-10-01

    We examined activation of concepts during analogical reasoning. Subjects made either analogical judgments or categorical judgments about four-word sets. After each four-word set, they named the ink color of a single word in a modified Stroop task. Words that referred to category relations were primed (as indicated by longer response times on Stroop color naming) subsequent to analogical judgments and categorical judgments. This finding suggests that activation of category concepts plays a fundamental role in analogical thinking. When colored words referred to analogical relations, priming occurred subsequent to analogical judgments, but not to categorical judgments, even though identical four-word stimuli were used for both types of judgments. This finding lends empirical support to the hypothesis that, when people comprehend the analogy between two items, they activate an abstract analogical relation that is distinct from the specific content items that compose the analogy.

  14. Analog series-based scaffolds: computational design and exploration of a new type of molecular scaffolds for medicinal chemistry

    Science.gov (United States)

    Dimova, Dilyana; Stumpfe, Dagmar; Hu, Ye; Bajorath, Jürgen

    2016-01-01

    Aim: Computational design of and systematic search for a new type of molecular scaffolds termed analog series-based scaffolds. Materials & methods: From currently available bioactive compounds, analog series were systematically extracted, key compounds identified and new scaffolds isolated from them. Results: Using our computational approach, more than 12,000 scaffolds were extracted from bioactive compounds. Conclusion: A new scaffold definition is introduced and a computational methodology developed to systematically identify such scaffolds, yielding a large freely available scaffold knowledge base. PMID:28116132

  15. AREUS - a software framework for the ATLAS Readout Electronics Upgrade Simulation

    CERN Document Server

    Horn, Philipp; The ATLAS collaboration

    2018-01-01

    The design of readout electronics for the LAr calorimeters of the ATLAS detector to be operated at the future High-Luminosity LHC (HL-LHC) requires a detailed simulation of the full readout chain in order to find optimal solutions for the analog and digital processing of the detector signals. Due to the long duration of the LAr calorimeter pulses relative to the LHC bunch crossing time, out-of-time signal pile-up needs to be taken intoaccountandrealisticpulsesequencesmustbesimulatedtogetherwiththeresponseoftheelectronics. For this purpose, the ATLAS Readout Electronics Upgrade Simulation framework (AREUS) has been developed based on the Observer design pattern to provide a fast and flexible simulation tool. Energy deposits in the LAr calorimeters from fully simulated HL-LHC collision events are taken as input. Simulated and measured analog pulse shapes proportional to these energies are then combined in discrete time series with proper representation of electronics noise. Analog-to-digital conversion, gain se...

  16. Toward Wireless Health Monitoring via an Analog Signal Compression-Based Biosensing Platform.

    Science.gov (United States)

    Zhao, Xueyuan; Sadhu, Vidyasagar; Le, Tuan; Pompili, Dario; Javanmard, Mehdi

    2018-06-01

    Wireless all-analog biosensor design for the concurrent microfluidic and physiological signal monitoring is presented in this paper. The key component is an all-analog circuit capable of compressing two analog sources into one analog signal by the analog joint source-channel coding (AJSCC). Two circuit designs are discussed, including the stacked-voltage-controlled voltage source (VCVS) design with the fixed number of levels, and an improved design, which supports a flexible number of AJSCC levels. Experimental results are presented on the wireless biosensor prototype, composed of printed circuit board realizations of the stacked-VCVS design. Furthermore, circuit simulation and wireless link simulation results are presented on the improved design. Results indicate that the proposed wireless biosensor is well suited for sensing two biological signals simultaneously with high accuracy, and can be applied to a wide variety of low-power and low-cost wireless continuous health monitoring applications.

  17. An analog VLSI real time optical character recognition system based on a neural architecture

    International Nuclear Information System (INIS)

    Bo, G.; Caviglia, D.; Valle, M.

    1999-01-01

    In this paper a real time Optical Character Recognition system is presented: it is based on a feature extraction module and a neural network classifier which have been designed and fabricated in analog VLSI technology. Experimental results validate the circuit functionality. The results obtained from a validation based on a mixed approach (i.e., an approach based on both experimental and simulation results) confirm the soundness and reliability of the system

  18. An analog VLSI real time optical character recognition system based on a neural architecture

    Energy Technology Data Exchange (ETDEWEB)

    Bo, G.; Caviglia, D.; Valle, M. [Genoa Univ. (Italy). Dip. of Biophysical and Electronic Engineering

    1999-03-01

    In this paper a real time Optical Character Recognition system is presented: it is based on a feature extraction module and a neural network classifier which have been designed and fabricated in analog VLSI technology. Experimental results validate the circuit functionality. The results obtained from a validation based on a mixed approach (i.e., an approach based on both experimental and simulation results) confirm the soundness and reliability of the system.

  19. Digitalization and networking of analog simulators and portal images

    Energy Technology Data Exchange (ETDEWEB)

    Pesznyak, C.; Zarand, P.; Mayer, A. [Uzsoki Hospital, Budapest (Hungary). Inst. of Oncoradiology

    2007-03-15

    Background: Many departments have analog simulators and irradiation facilities (especially cobalt units) without electronic portal imaging. Import of the images into the R and V (Record and Verify) system is required. Material and Methods: Simulator images are grabbed while portal films scanned by using a laser scanner and both converted into DICOM RT (Digital Imaging and Communications in Medicine Radiotherapy) images. Results: Image intensifier output of a simulator and portal films are converted to DICOM RT images and used in clinical practice. The simulator software was developed in cooperation at the authors' hospital. Conclusion: The digitalization of analog simulators is a valuable updating in clinical use replacing screen-film technique. Film scanning and digitalization permit the electronic archiving of films. Conversion into DICOM RT images is a precondition of importing to the R and V system. (orig.)

  20. A mixed analog-digital radiation hard technology for high energy physics electronics DMILL (Durci Mixte sur Isolant Logico-Linéaire)

    CERN Document Server

    Beuville, E; Borgeaud, P; Fourches, N T; Rouger, M; Blanc, J P; Bruel, M; Delevoye-Orsier, E; Gautier, J; Du Port de Pontcharra, J; Truche, R; Dupont-Nivet, E; Flament, O; Leray, J L; Martin, J L; Montaron, J; Borel, G; Brice, J M; Chatagnon, P; Terrier, C; Aubert, Jean-Jacques; Delpierre, P A; Habrard, M C; Potheau, R; CERN. Geneva. Detector Research and Development Committee

    1992-01-01

    The high radiation level expected in the inner regions of the high luminosity LHC detectors (gamma and neutron) will require radiation hardened electronics. A consortium between the CEA (Commissariat a l'Energie Atomique) and Thomson TMS (Thomson Composants Militaires et Spatiaux) has been created to push for the development and the industrialization of a nascent technology which looks particularly adapted to the needs of HEP electronics. This technology, currently under development at the LETI(CEA), uses a SIMOX substrate with an epitaxial silicon film. It includes CMOS, JFETs and vertical bipolar transistors with a potential multi-megarad hardness. The CMOS and bipolar transistors constitute a rad-hard BiCMOS which will be useful to design analog and digital high-speed architectures. JFETs, which have intrinsically high hardness behaviour and low noise performances even at low temperature will enable very rad-hard, low noise front end electronics to be designed. Present results, together with the improvemen...

  1. Computational design of new molecular scaffolds for medicinal chemistry, part II: generalization of analog series-based scaffolds

    Science.gov (United States)

    Dimova, Dilyana; Stumpfe, Dagmar; Bajorath, Jürgen

    2018-01-01

    Aim: Extending and generalizing the computational concept of analog series-based (ASB) scaffolds. Materials & methods: Methodological modifications were introduced to further increase the coverage of analog series (ASs) and compounds by ASB scaffolds. From bioactive compounds, ASs were systematically extracted and second-generation ASB scaffolds isolated. Results: More than 20,000 second-generation ASB scaffolds with single or multiple substitution sites were extracted from active compounds, achieving more than 90% coverage of ASs. Conclusion: Generalization of the ASB scaffold approach has yielded a large knowledge base of scaffold-capturing compound series and target information. PMID:29379641

  2. A 6 device SOI new technology for mixed analog-digital and rad-hard applications

    International Nuclear Information System (INIS)

    Blanc, J.P.; Bonaime, J.; Delevoye, E.; Pontcharra, J. de; Gautier, J.; Truche, R.

    1993-01-01

    DMILL technology is being developed for very rad-hard analog-digital applications, such as space and military circuits or as electronics for the future generation of high energy collider (LHC, CERN, Geneva). Both CMOS and junction (JFET and bipolar) transistors are needed. A new process has been integrated, based on a 1.2μm thick silicon film on insulator (SIMOX plus epitaxy), a complete dielectric isolation and low temperature process. The mean feature is that six different components are fabricated on the same wafer, taking into account the 12 volts supply voltage constraint for some analog applications. The first electrical characteristics are presented in this paper. The optimization capabilities of such a hardened CBi-CJ-CMOS technology are discussed

  3. Analog implementation of an integral resonant control scheme

    International Nuclear Information System (INIS)

    Pereira, E; Moheimani, S O R; Aphale, S S

    2008-01-01

    Integral resonant control (IRC) has been introduced as a high performance controller design methodology for flexible structures with collocated actuator–sensor pairs. IRC has a simple structure and is capable of achieving significant damping, over several modes, while guaranteeing closed-loop stability of the system in the presence of unmodeled out-of-bandwidth dynamics. IRC can be an ideal controller for various industrial damping applications, if packaged in a simple easy-to-implement electronic module. This work proposes an analog implementation of the IRC scheme using a single Op-Amp circuit. The objective is to show that with simple analog realization of the modified IRC scheme, it is possible to damp a large number of vibration modes. A brief discussion about the modeling, circuit considerations, implementation and experimental results is presented in order to validate the usefulness and practicality of the proposed analog IRC implementation. (technical note)

  4. A Physical Analog Model of Strike-Slip Faulting for Model-Based Inquiry in the Classroom

    Science.gov (United States)

    Curren, I. S.; Glesener, G.

    2013-12-01

    classroom setting. We hope to encourage discussion from session attendees on the use of physical analog models and real-time quantitative model-based inquiry in the development of the next generation of geoscientists.

  5. Source selection for analogical reasoning an empirical approach

    Energy Technology Data Exchange (ETDEWEB)

    Stubblefield, W.A. [Sandia National Labs., Albuquerque, NM (United States); Luger, G.F. [Univ. of New Mexico, Albuquerque, NM (United States)

    1996-12-31

    The effectiveness of an analogical reasoner depends upon its ability to select a relevant analogical source. In many problem domains, however, too little is known about target problems to support effective source selection. This paper describes the design and evaluation of SCAVENGER, an analogical reasoner that applies two techniques to this problem: (1) An assumption-based approach to matching that allows properties of candidate sources to match unknown target properties in the absence of evidence to the contrary. (2) The use of empirical learning to improve memory organization based on problem solving experience.

  6. A fast multichannel analog storage system

    International Nuclear Information System (INIS)

    Freytag, D.R.

    1983-01-01

    A Multichannel Analog Storage System based on a commercial 32-channel parallel in/serial out (PISO) analog shift register is described. The basic unit is a single width CAMAC module containing 512 analog cells and the associated logic for data storage and subsequent readout. At sampling rates of up to 30 MHz the signals are strobed directly into the PISO. At higher rates signals are strobed into a fast presampling stage and subsequently transferred in block form into an array of PISO's. Sampling rates of 300 MHz have been achieved with the present device and 1000 MHz are possible with improved signal drivers. The system is well suited for simultaneous handling of many signal channels with moderate numbers of samples in each channel. RMS noise over full scale signal has been measured as 1:3000 (approx. =11 bit). However, nonlinearities in the response and differences in sensitivity of the analog cells require an elaborate calibration system in order to realize 11 bit accuracy for the analog information

  7. Design rules for superconducting analog-digital transducers

    International Nuclear Information System (INIS)

    Haddad, Taghrid

    2015-01-01

    This Thesis is a contribution for dimensioning aspects of circuits designs in superconductor electronics. Mainly superconductor comparators inclusive Josephson comparators as well as QOJS-Comparators are investigated. Both types were investigated in terms of speed and sensitivity. The influence of the thermal noise on the decision process of the comparators represent in so called gray zone, which is analysed in this thesis. Thereby, different relations between design parameters were derived. A circuit model of the Josephson comparator was verified by experiments. Concepts of superconductor analog-to-digital converters, which are based on above called comparators, were investigated in detail. From the comparator design rules, new rules for AD-converters were derived. Because of the reduced switching energy, the signal to noise ratio (SNR) of the circuits is affected and therefore the reliability of the decision-process is affected. For special applications with very demanding requirements in terms of the speed and accuracy superconductor analog-to-digital converters offer an excellent performance. This thesis provides relations between different design paramenters and shows resulting trade-offs, This method is transparent and easy to transfer to other circuit topologies. As a main result, a highly predictive tool for dimensioning of superconducting ADC's is proved.

  8. VHDL-based programming environment for Floating-Gate analog memory cell

    Directory of Open Access Journals (Sweden)

    Carlos Alberto dos Reis Filho

    2005-02-01

    Full Text Available An implementation in CMOS technology of a Floating-Gate Analog Memory Cell and Programming Environment is presented. A digital closed-loop control compares a reference value set by user and the memory output and after cycling, the memory output is updated and the new value stored. The circuit can be used as analog trimming for VLSI applications where mechanical trimming associated with postprocessing chip is prohibitive due to high costs.

  9. FPGA-based upgrade of the read-out electronics for the low energy polarimeter at the cooler synchrotron

    Energy Technology Data Exchange (ETDEWEB)

    Hempelmann, Nils [Institut fuer Kernphysik, Forschungszentrum Juelich (Germany); Collaboration: JEDI-Collaboration

    2015-07-01

    The Cooler Synchrotron (COSY) is a storage ring used for experiments with polarized proton and deuteron beams. The low energy polarimeter is used to determine the vector and tensor polarization of the beam before injection at kinetic energies up to 45 MeV for protons and 75 MeV for deuterons. The polarimeter uses scintillators to measure the energy of both outgoing particles of a scattering reaction and the time between their detection. The present read-out electronics consists of analog NIM modules and is limited in terms of time resolution and the capability for online data analysis. The read-out electronics will be replaced with a a new system based on analog pulse sampling and an FPGA chip for logic operations. The new system will be able to measure the time at which particles arrive to a precision better than 50 ps, facilitating better background reduction using coincidence measurement. In addition to measuring the beam polarization, the system will be used to precisely determine the vector and tensor analyzing powers for deuteron scattering off carbon at a kinetic energy of 75 MeV.

  10. Communication disruption of guava moth (Coscinoptycha improbana) using a pheromone analog based on chain length.

    Science.gov (United States)

    Suckling, D M; Dymock, J J; Park, K C; Wakelin, R H; Jamieson, L E

    2013-09-01

    The guava moth, Coscinoptycha improbana, an Australian species that infests fruit crops in commercial and home orchards, was first detected in New Zealand in 1997. A four-component pheromone blend was identified but is not yet commercially available. Using single sensillum recordings from male antennae, we established that the same olfactory receptor neurons responded to two guava moth sex pheromone components, (Z)-11-octadecen-8-one and (Z)-12-nonadecen-9-one, and to a chain length analog, (Z)-13-eicosen-10-one, the sex pheromone of the related peach fruit moth, Carposina sasakii. We then field tested whether this non-specificity of the olfactory neurons might enable disruption of sexual communication by the commercially available analog, using male catch to synthetic lures in traps in single-tree, nine-tree and 2-ha plots. A disruptive pheromone analog, based on chain length, is reported for the first time. Trap catches for guava moth were disrupted by three polyethylene tubing dispensers releasing the analog in single-tree plots (86% disruption of control catches) and in a plots of nine trees (99% disruption). Where peach fruit moth pheromone dispensers were deployed at a density of 1000/ha in two 2-ha areas, pheromone traps for guava moth were completely disrupted for an extended period (up to 470 days in peri-urban gardens in Mangonui and 422 days in macadamia nut orchards in Kerikeri). In contrast, traps in untreated areas over 100 m away caught 302.8 ± 128.1 moths/trap in Mangonui and 327.5 ± 78.5 moths/ trap in Kerikeri. The longer chain length in the pheromone analog has greater longevity than the natural pheromone due to its lower volatility. Chain length analogs may warrant further investigation for mating disruption in Lepidoptera, and screening using single-sensillum recording is recommended.

  11. Direct Detection of Complex Organic Products in Ultraviolet (Lyα) and Electron-irradiated Astrophysical and Cometary Ice Analogs Using Two-step Laser Ablation and Ionization Mass Spectrometry

    Science.gov (United States)

    Henderson, Bryana L.; Gudipati, Murthy S.

    2015-02-01

    As discovery of complex molecules and ions in our solar system and the interstellar medium has proliferated, several groups have turned to laboratory experiments in an effort to simulate and understand these chemical processes. So far only infrared (IR) and ultraviolet (UV) spectroscopy has been able to directly probe these reactions in ices in their native, low-temperature states. Here we report for the first time results using a complementary technique that harnesses two-step two-color laser ablation and ionization to measure mass spectra of energetically processed astrophysical and cometary ice analogs directly without warming the ices—a method for hands-off in situ ice analysis. Electron bombardment and UV irradiation of H2O, CH3OH, and NH3 ices at 5 K and 70 K led to complex irradiation products, including HCO, CH3CO, formamide, acetamide, methyl formate, and HCN. Many of these species, whose assignment was also strengthened by isotope labeling studies and correlate with IR-based spectroscopic studies of similar irradiated ices, are important ingredients for the building blocks of life. Some of them have been detected previously via astronomical observations in the interstellar medium and in cometary comae. Other species such as CH3CO (acetyl) are yet to be detected in astrophysical ices or interstellar medium. Our studies suggest that electron and UV photon processing of astrophysical ice analogs leads to extensive chemistry even in the coldest reaches of space, and lend support to the theory of comet-impact-induced delivery of complex organics to the inner solar system.

  12. Science Teachers' Analogical Reasoning

    Science.gov (United States)

    Mozzer, Nilmara Braga; Justi, Rosária

    2013-08-01

    Analogies can play a relevant role in students' learning. However, for the effective use of analogies, teachers should not only have a well-prepared repertoire of validated analogies, which could serve as bridges between the students' prior knowledge and the scientific knowledge they desire them to understand, but also know how to introduce analogies in their lessons. Both aspects have been discussed in the literature in the last few decades. However, almost nothing is known about how teachers draw their own analogies for instructional purposes or, in other words, about how they reason analogically when planning and conducting teaching. This is the focus of this paper. Six secondary teachers were individually interviewed; the aim was to characterize how they perform each of the analogical reasoning subprocesses, as well as to identify their views on analogies and their use in science teaching. The results were analyzed by considering elements of both theories about analogical reasoning: the structural mapping proposed by Gentner and the analogical mechanism described by Vosniadou. A comprehensive discussion of our results makes it evident that teachers' content knowledge on scientific topics and on analogies as well as their pedagogical content knowledge on the use of analogies influence all their analogical reasoning subprocesses. Our results also point to the need for improving teachers' knowledge about analogies and their ability to perform analogical reasoning.

  13. Modified friction factor correlation for CICC's based on a porous media analogy

    Science.gov (United States)

    Lewandowska, Monika; Bagnasco, Maurizio

    2011-09-01

    A modified correlation for the bundle friction factor in CICC's based on a porous media analogy is presented. The correlation is obtained by the analysis of the collected pressure drop data measured for 23 CICC's. The friction factors predicted by the proposed correlation are compared with those resulting from the pressure drop data for two CICC's measured recently using cryogenic helium in the SULTAN test facility at EPFL-CRPP.

  14. Introduction to electronics

    CERN Multimedia

    CERN. Geneva

    2005-01-01

    Electronics in HEP experiments: specificities and evolution The Art of Electronics: is there something beyond Ohm's law? Basic building blocks of Analog electronics: quickly understanding a schematic Charge preamps, current preamps and future preamps, shaping and the rest Electronics noise: fundamental and practical Evolution of technology: ASICs, FPGAs...

  15. SEAS: A simulated evolution approach for analog circuit synthesis

    NARCIS (Netherlands)

    Ning, Zhen-Qiu; Ning, Zhen-Qiu; Mouthaan, A.J.; Wallinga, Hans

    1991-01-01

    The authors present a simulated evolution approach for analog circuit synthesis based on an analogy with the natural selection process in biological environments and on the iterative improvements in solving engineering problems. A prototype framework based on this idea, called SEAS, has been

  16. Electron transfer driven decomposition of adenine and selected analogs as probed by experimental and theoretical methods

    Science.gov (United States)

    Cunha, T.; Mendes, M.; Ferreira da Silva, F.; Eden, S.; García, G.; Bacchus-Montabonel, M.-C.; Limão-Vieira, P.

    2018-04-01

    We report on a combined experimental and theoretical study of electron-transfer-induced decomposition of adenine (Ad) and a selection of analog molecules in collisions with potassium (K) atoms. Time-of-flight negative ion mass spectra have been obtained in a wide collision energy range (6-68 eV in the centre-of-mass frame), providing a comprehensive investigation of the fragmentation patterns of purine (Pu), adenine (Ad), 9-methyl adenine (9-mAd), 6-dimethyl adenine (6-dimAd), and 2-D adenine (2-DAd). Following our recent communication about selective hydrogen loss from the transient negative ions (TNIs) produced in these collisions [T. Cunha et al., J. Chem. Phys. 148, 021101 (2018)], this work focuses on the production of smaller fragment anions. In the low-energy part of the present range, several dissociation channels that are accessible in free electron attachment experiments are absent from the present mass spectra, notably NH2 loss from adenine and 9-methyl adenine. This can be understood in terms of a relatively long transit time of the K+ cation in the vicinity of the TNI tending to enhance the likelihood of intramolecular electron transfer. In this case, the excess energy can be redistributed through the available degrees of freedom inhibiting fragmentation pathways. Ab initio theoretical calculations were performed for 9-methyl adenine (9-mAd) and adenine (Ad) in the presence of a potassium atom and provided a strong basis for the assignment of the lowest unoccupied molecular orbitals accessed in the collision process.

  17. Elevated Levels of DNA Strand Breaks Induced by a Base Analog in the Human Cell Line with the P32T ITPA Variant

    Science.gov (United States)

    Waisertreiger, Irina S.-R.; Menezes, Miriam R.; Randazzo, James; Pavlov, Youri I.

    2010-01-01

    Base analogs are powerful antimetabolites and dangerous mutagens generated endogenously by oxidative stress, inflammation, and aberrant nucleotide biosynthesis. Human inosine triphosphate pyrophosphatase (ITPA) hydrolyzes triphosphates of noncanonical purine bases (i.e., ITP, dITP, XTP, dXTP, or their mimic: 6-hydroxyaminopurine (HAP) deoxynucleoside triphosphate) and thus regulates nucleotide pools and protects cells from DNA damage. We demonstrate that the model purine base analog HAP induces DNA breaks in human cells and leads to elevation of levels of ITPA. A human polymorphic allele of the ITPA, 94C->A encodes for the enzyme with a P32T amino-acid change and leads to accumulation of nonhydrolyzed ITP. The polymorphism has been associated with adverse reaction to purine base-analog drugs. The level of both spontaneous and HAP-induced DNA breaks is elevated in the cell line with the ITPA P32T variant. The results suggested that human ITPA plays a pivotal role in the protection of DNA from noncanonical purine base analogs. PMID:20936128

  18. Elevated Levels of DNA Strand Breaks Induced by a Base Analog in the Human Cell Line with the P32T ITPA Variant

    Directory of Open Access Journals (Sweden)

    Irina S.-R. Waisertreiger

    2010-01-01

    Full Text Available Base analogs are powerful antimetabolites and dangerous mutagens generated endogenously by oxidative stress, inflammation, and aberrant nucleotide biosynthesis. Human inosine triphosphate pyrophosphatase (ITPA hydrolyzes triphosphates of noncanonical purine bases (i.e., ITP, dITP, XTP, dXTP, or their mimic: 6-hydroxyaminopurine (HAP deoxynucleoside triphosphate and thus regulates nucleotide pools and protects cells from DNA damage. We demonstrate that the model purine base analog HAP induces DNA breaks in human cells and leads to elevation of levels of ITPA. A human polymorphic allele of the ITPA, 94C->A encodes for the enzyme with a P32T amino-acid change and leads to accumulation of nonhydrolyzed ITP. The polymorphism has been associated with adverse reaction to purine base-analog drugs. The level of both spontaneous and HAP-induced DNA breaks is elevated in the cell line with the ITPA P32T variant. The results suggested that human ITPA plays a pivotal role in the protection of DNA from noncanonical purine base analogs.

  19. Analogy, an Alternative Model.
 Critics to the standard model of analogical problems solving and proposals for an alternative one

    Directory of Open Access Journals (Sweden)

    Ricardo A. Minervino

    2016-02-01

    Full Text Available The authors made an extension of Hofstadter‘s criticisms against the standard approach in analogical thinking represented by the structure-mapping theory of Gentner and the multiconstraint theory of Holyoak and Thagard. Based on this extension, they proposed a non-serial model of analogical problem solving. Against the standard approach, the model postulates that: (a people detect and evaluate differences between mapped elements before the subprocess of inference generation and consider them in order to control it, and (b properties of an element that explain why the element could fill a certain role in the base problem resolution (PERs play a crucial role in these detection and evaluation operations, and also in post-inferences subprocesses. An experiment showed that: (a people detect and evaluate the relevance of differences between mapped elements before inference generation, (b that they inhibit the generation of literal inferences when they face relevant differences, and (c that they stop the subprocess when they recognize insuperable ones. The results also showed that base PERs are reactivated at different moments of analogical transfer. The data obtained are incompatible with the standard theories of analogical thinking, which treat inference generation as a syntactic mechanism and exclude contextual semantic analysis from the study of analogy

  20. Band electron spectrum and thermodynamic properties of the pseudospin-electron model with tunneling splitting of levels

    Directory of Open Access Journals (Sweden)

    O.Ya.Farenyuk

    2006-01-01

    Full Text Available The pseudospin-electron model with tunneling splitting of levels is considered. Generalization of dynamic mean-field method for systems with correlated hopping was applied to the investigation of the model. Electron spectra, electron concentrations, average values of pseudospins and grand canonical potential were calculated within the alloy-analogy approximation. Electron spectrum and dependencies of the electron concentrations on chemical potential were obtained. It was shown that in the alloy-analogy approximation, the model possesses the first order phase transition to ferromagnetic state with the change of chemical potential and the second order phase transition with the change of temperature.

  1. Acoustic analog of monolayer graphene and edge states

    International Nuclear Information System (INIS)

    Zhong, Wei; Zhang, Xiangdong

    2011-01-01

    Acoustic analog of monolayer graphene has been designed by using silicone rubber spheres of honeycomb lattices embedded in water. The dispersion of the structure has been studied theoretically using the rigorous multiple-scattering method. The energy spectra with the Dirac point have been verified and zigzag edge states have been found in ribbons of the structure, which are analogous to the electronic ones in graphene nanoribbons. The guided modes along the zigzag edge excited by a point source have been numerically demonstrated. The open cavity and 'Z' type edge waveguide with 60 o corners have also been realized by using such edge states. -- Highlights: → Acoustic analog of monolayer graphene has been designed. → The energy spectra with the Dirac point have been verified. → The zigzag edge states have been found in ribbons of the structure. → The guided modes excited by a point source have been demonstrated. → The open cavity and 'Z' type edge waveguide have been realized.

  2. Learning Plate Tectonics Using a Pre-Analogy Step

    Science.gov (United States)

    Glesener, G. B.; Sandoval, W. A.

    2011-12-01

    Previous research has shown that children tend to demonstrate lower performance on analogical reasoning tasks at a causal relations level compared to most adults (Gentner & Toupin, 1986). This tendency is an obstacle that geoscience educators must overcome because of the high frequency of analogies used in geoscience pedagogy. In particular, analog models are used to convey complex systems of non-everyday/non-observable events found in nature, such as plate tectonics. Key factors in successful analogical reasoning that have been suggested by researchers include knowledge of the causal relations in the base analog (Brown & Kane, 1988; Gentner, 1988; Gentner & Toupin, 1986), and development of learning strategies and metaconceptual competence(Brown & Kane, 1988). External factors, such as guiding cues and hints have been useful cognitive supports that help students reason through analogical problems (Gick & Holyoak, 1980). Cognitive supports have been seen by researchers to decrease processing demands on retrieval and working memory (Richland, Zur, & Holyoak, 2007). We observed third and fourth graders learning about plate tectonics beginning with a pre-analogy step-a cognitive support activity a student can do before working with an analogy to understand the target. This activity was designed to aid students in developing their understanding of object attributes and relations within an analog model so that more focus can be placed on mapping the corresponding higher-order relations between the base and target. Students learned targeted concepts of plate tectonics, as measured by pre to post gains on items adapted from the Geosciences Concept Inventory. Analyses of classroom interaction showed that students used the object attributes and higher-order relations highlighted in the pre-analogy activity as resources to reason about plate boundaries and plate movement during earthquakes.

  3. Development of analog watch with minute repeater

    Science.gov (United States)

    Okigami, Tomio; Aoyama, Shigeru; Osa, Takashi; Igarashi, Kiyotaka; Ikegami, Tomomi

    A complementary metal oxide semiconductor with large scale integration was developed for an electronic minute repeater. It is equipped with the synthetic struck sound circuit to generate natural struck sound necessary for the minute repeater. This circuit consists of an envelope curve drawing circuit, frequency mixer, polyphonic mixer, and booster circuit made by using analog circuit technology. This large scale integration is a single chip microcomputer with motor drivers and input ports in addition to the synthetic struck sound circuit, and it is possible to make an electronic system of minute repeater at a very low cost in comparison with the conventional type.

  4. Epistemology of analogy: Knowledge, society and expression

    Directory of Open Access Journals (Sweden)

    Mauricio Beuchot

    2017-06-01

    Full Text Available In this article we expose the bases of analog epistemology. This theory of knowledge is between an extreme subjectivism and an extreme objectivism. Analog hermeneutics is a realistic hermeneutics. She seeks the truth, but incorporates the meaning and emotion. We have separated the reason from the experience, the praxis theory, the mind or the soul of the body. We have to get them back together, if we do not get lost in the rational (which says little of the human being, or we lose ourselves in the emotional (without logical consistency. The analogical hermeneutic realism is able, thanks to the analogy itself, to mediate in this way of union.

  5. Quantum Analog Computing

    Science.gov (United States)

    Zak, M.

    1998-01-01

    Quantum analog computing is based upon similarity between mathematical formalism of quantum mechanics and phenomena to be computed. It exploits a dynamical convergence of several competing phenomena to an attractor which can represent an externum of a function, an image, a solution to a system of ODE, or a stochastic process.

  6. High-frequency analog integrated circuit design

    CERN Document Server

    1995-01-01

    To learn more about designing analog integrated circuits (ICs) at microwave frequencies using GaAs materials, turn to this text and reference. It addresses GaAs MESFET-based IC processing. Describes the newfound ability to apply silicon analog design techniques to reliable GaAs materials and devices which, until now, was only available through technical papers scattered throughout hundred of articles in dozens of professional journals.

  7. Josephson junction analog and quasiparticle-pair current

    DEFF Research Database (Denmark)

    Bak, Christen Kjeldahl; Pedersen, Niels Falsig

    1973-01-01

    A close analogy exists between a Josephson junction and a phase-locked loop. A new type of electrical analog based on this principle is presented. It is shown that the inclusion in this analog of a low-pass filter gives rise to a current of the same form as the Josephson quasiparticle-pair current....... A simple picture of the quasiparticle-pair current, which gives the right dependences, is obtained by assuming a junction cutoff frequency to be at the energy gap. ©1973 American Institute of Physics...

  8. Fast parallel-series analog-to-digital converter

    International Nuclear Information System (INIS)

    Pogosov, A.Yu.

    1987-01-01

    Fast analog-to-digital converters are used in systems for detection of rapid processes, nuclear spectroscopy. A 12-digit analog-to-digital converter with conversion time of 160 ns and conversion frequency of 8.3 MHz is described; a segmented digital-to-analog converter with differential non-linearity of < 0.01% and a differential amplifier-limiter with setting time of 80 ns at the error of 0.2% are utilized in the converter; a control device is based on the chain of flip-flop circuit

  9. Analog lightwave links for detector front-ends at the LHC

    International Nuclear Information System (INIS)

    Baird, A.; Dowell, J.; Duthie, P.

    1995-01-01

    Lightwave links are being developed for volume application in the transfer of analog signals from the tracking detector front-ends to the readout electronics. The links are based on electro-optic intensity modulators which are mounted on detectors and connected by optical fibers to remotely located transceivers (lasers and photoreceivers). The modulators are 3--5 semiconductor reflective devices based on multi-quantum well structures. The transceivers will be integrated devices of a novel design. Modulator prototypes have been fabricated and tested. Neutron and γ-ray irradiation studies have been performed on modulators and fibers. The main results achieved so far are reported and key system issues are reviewed. This work is part of the CERN DRDC project RD23 project RD23

  10. Electronic plants

    Science.gov (United States)

    Stavrinidou, Eleni; Gabrielsson, Roger; Gomez, Eliot; Crispin, Xavier; Nilsson, Ove; Simon, Daniel T.; Berggren, Magnus

    2015-01-01

    The roots, stems, leaves, and vascular circuitry of higher plants are responsible for conveying the chemical signals that regulate growth and functions. From a certain perspective, these features are analogous to the contacts, interconnections, devices, and wires of discrete and integrated electronic circuits. Although many attempts have been made to augment plant function with electroactive materials, plants’ “circuitry” has never been directly merged with electronics. We report analog and digital organic electronic circuits and devices manufactured in living plants. The four key components of a circuit have been achieved using the xylem, leaves, veins, and signals of the plant as the template and integral part of the circuit elements and functions. With integrated and distributed electronics in plants, one can envisage a range of applications including precision recording and regulation of physiology, energy harvesting from photosynthesis, and alternatives to genetic modification for plant optimization. PMID:26702448

  11. Analog forecasting with dynamics-adapted kernels

    Science.gov (United States)

    Zhao, Zhizhen; Giannakis, Dimitrios

    2016-09-01

    Analog forecasting is a nonparametric technique introduced by Lorenz in 1969 which predicts the evolution of states of a dynamical system (or observables defined on the states) by following the evolution of the sample in a historical record of observations which most closely resembles the current initial data. Here, we introduce a suite of forecasting methods which improve traditional analog forecasting by combining ideas from kernel methods developed in harmonic analysis and machine learning and state-space reconstruction for dynamical systems. A key ingredient of our approach is to replace single-analog forecasting with weighted ensembles of analogs constructed using local similarity kernels. The kernels used here employ a number of dynamics-dependent features designed to improve forecast skill, including Takens’ delay-coordinate maps (to recover information in the initial data lost through partial observations) and a directional dependence on the dynamical vector field generating the data. Mathematically, our approach is closely related to kernel methods for out-of-sample extension of functions, and we discuss alternative strategies based on the Nyström method and the multiscale Laplacian pyramids technique. We illustrate these techniques in applications to forecasting in a low-order deterministic model for atmospheric dynamics with chaotic metastability, and interannual-scale forecasting in the North Pacific sector of a comprehensive climate model. We find that forecasts based on kernel-weighted ensembles have significantly higher skill than the conventional approach following a single analog.

  12. Acoustic analog computing based on a reflective metasurface with decoupled modulation of phase and amplitude

    Science.gov (United States)

    Zuo, Shu-Yu; Tian, Ye; Wei, Qi; Cheng, Ying; Liu, Xiao-Jun

    2018-03-01

    The use of metasurfaces has allowed the provision of a variety of functionalities by ultrathin structures, paving the way toward novel highly compact analog computing devices. Here, we conceptually realize analog computing using an acoustic reflective computational metasurface (RCM) that can independently manipulate the reflection phase and amplitude of an incident acoustic signal. This RCM is composed of coating unit cells and perforated panels, where the first can tune the transmission phase within the full range of 2π and the second can adjust the reflection amplitude in the range of 0-1. We show that this RCM can achieve arbitrary reflection phase and amplitude and can be used to realize a unique linear spatially invariant transfer function. Using the spatial Fourier transform (FT), an acoustic analog computing (AAC) system is proposed based on the RCM together with a focusing lens. Based on numerical simulations, we demonstrate that this AAC system can perform mathematical operations such as spatial differentiation, integration, and convolution on an incident acoustic signal. The proposed system has low complexity and reduced size because the RCM is able to individually adjust the reflection phase and amplitude and because only one block is involved in performing the spatial FT. Our work may offer a practical, efficient, and flexible approach to the design of compact devices for acoustic computing applications, signal processing, equation solving, and acoustic wave manipulations.

  13. Los pasiegos. La analogía salvaje y lo salvaje de la analogía

    Directory of Open Access Journals (Sweden)

    JAIME DE LA CALLE VALVERDE

    2007-01-01

    -entendiendo salvaje como un pensamiento humano prístino-: por un lado en sus relaciones con el racionalismo (¿emerge la analogía desde el racionalismo?, ¿qué relación guarda con éste?, ¿su nacimiento es resultado de una función «natural»? y por otro sobre la naturaleza social de lo salvaje a partir de las bases sociales que lo producen. Es decir, se rastrea lo que de salvaje tiene la analogía, si la analogía es o no una función ahistórica y asocial del intelecto humano. No se examina todo el complejo analógico de los pasiegos, únicamente aquél que establece relaciones homólogas entre las vacas y el entorno.

  14. Visualizing Uncertainty for Probabilistic Weather Forecasting based on Reforecast Analogs

    Science.gov (United States)

    Pelorosso, Leandro; Diehl, Alexandra; Matković, Krešimir; Delrieux, Claudio; Ruiz, Juan; Gröeller, M. Eduard; Bruckner, Stefan

    2016-04-01

    Numerical weather forecasts are prone to uncertainty coming from inaccuracies in the initial and boundary conditions and lack of precision in numerical models. Ensemble of forecasts partially addresses these problems by considering several runs of the numerical model. Each forecast is generated with different initial and boundary conditions and different model configurations [GR05]. The ensembles can be expressed as probabilistic forecasts, which have proven to be very effective in the decision-making processes [DE06]. The ensemble of forecasts represents only some of the possible future atmospheric states, usually underestimating the degree of uncertainty in the predictions [KAL03, PH06]. Hamill and Whitaker [HW06] introduced the "Reforecast Analog Regression" (RAR) technique to overcome the limitations of ensemble forecasting. This technique produces probabilistic predictions based on the analysis of historical forecasts and observations. Visual analytics provides tools for processing, visualizing, and exploring data to get new insights and discover hidden information patterns in an interactive exchange between the user and the application [KMS08]. In this work, we introduce Albero, a visual analytics solution for probabilistic weather forecasting based on the RAR technique. Albero targets at least two different type of users: "forecasters", who are meteorologists working in operational weather forecasting and "researchers", who work in the construction of numerical prediction models. Albero is an efficient tool for analyzing precipitation forecasts, allowing forecasters to make and communicate quick decisions. Our solution facilitates the analysis of a set of probabilistic forecasts, associated statistical data, observations and uncertainty. A dashboard with small-multiples of probabilistic forecasts allows the forecasters to analyze at a glance the distribution of probabilities as a function of time, space, and magnitude. It provides the user with a more

  15. Rhetoric and analogies

    OpenAIRE

    Aragonès, Enriqueta; Gilboa, Itzhak; Postlewaite, Andrew; Schmeidler, David; Universitat Autònoma de Barcelona. Unitat de Fonaments de l'Anàlisi Econòmica; Universitat Autònoma de Barcelona. Institut d'Anàlisi Econòmica

    2013-01-01

    The art of rhetoric may be defined as changing other people's minds (opinions, beliefs) without providing them new information. One tech- nique heavily used by rhetoric employs analogies. Using analogies, one may draw the listener's attention to similarities between cases and to re-organize existing information in a way that highlights certain reg- ularities. In this paper we offer two models of analogies, discuss their theoretical equivalence, and show that finding good analogies is a com- p...

  16. Event-Based Computation of Motion Flow on a Neuromorphic Analog Neural Platform.

    Science.gov (United States)

    Giulioni, Massimiliano; Lagorce, Xavier; Galluppi, Francesco; Benosman, Ryad B

    2016-01-01

    Estimating the speed and direction of moving objects is a crucial component of agents behaving in a dynamic world. Biological organisms perform this task by means of the neural connections originating from their retinal ganglion cells. In artificial systems the optic flow is usually extracted by comparing activity of two or more frames captured with a vision sensor. Designing artificial motion flow detectors which are as fast, robust, and efficient as the ones found in biological systems is however a challenging task. Inspired by the architecture proposed by Barlow and Levick in 1965 to explain the spiking activity of the direction-selective ganglion cells in the rabbit's retina, we introduce an architecture for robust optical flow extraction with an analog neuromorphic multi-chip system. The task is performed by a feed-forward network of analog integrate-and-fire neurons whose inputs are provided by contrast-sensitive photoreceptors. Computation is supported by the precise time of spike emission, and the extraction of the optical flow is based on time lag in the activation of nearby retinal neurons. Mimicking ganglion cells our neuromorphic detectors encode the amplitude and the direction of the apparent visual motion in their output spiking pattern. Hereby we describe the architectural aspects, discuss its latency, scalability, and robustness properties and demonstrate that a network of mismatched delicate analog elements can reliably extract the optical flow from a simple visual scene. This work shows how precise time of spike emission used as a computational basis, biological inspiration, and neuromorphic systems can be used together for solving specific tasks.

  17. Reference-Free CMOS Pipeline Analog-to-Digital Converters

    CERN Document Server

    Figueiredo, Michael; Evans, Guiomar

    2013-01-01

    This book shows that digitally assisted analog-to-digital converters are not the only way to cope with poor analog performance caused by technology scaling. It describes various analog design techniques that enhance the area and power efficiency without employing any type of digital calibration circuitry. These techniques consist of self-biasing for PVT enhancement, inverter-based design for improved speed/power ratio, gain-of-two obtained by voltage sum instead of charge redistribution, and current-mode reference shifting instead of voltage reference shifting. Together, these techniques allow enhancing the area and power efficiency of the main building blocks of a multiplying digital-to-analog converter (MDAC) based stage, namely, the flash quantizer, the amplifier, and the switched capacitor network of the MDAC. Complementing the theoretical analyses of the various techniques, a power efficient operational transconductance amplifier is implemented and experimentally characterized. Furthermore, a medium-low ...

  18. Effective Low-Power Wearable Wireless Surface EMG Sensor Design Based on Analog-Compressed Sensing

    Directory of Open Access Journals (Sweden)

    Mohammadreza Balouchestani

    2014-12-01

    Full Text Available Surface Electromyography (sEMG is a non-invasive measurement process that does not involve tools and instruments to break the skin or physically enter the body to investigate and evaluate the muscular activities produced by skeletal muscles. The main drawbacks of existing sEMG systems are: (1 they are not able to provide real-time monitoring; (2 they suffer from long processing time and low speed; (3 they are not effective for wireless healthcare systems because they consume huge power. In this work, we present an analog-based Compressed Sensing (CS architecture, which consists of three novel algorithms for design and implementation of wearable wireless sEMG bio-sensor. At the transmitter side, two new algorithms are presented in order to apply the analog-CS theory before Analog to Digital Converter (ADC. At the receiver side, a robust reconstruction algorithm based on a combination of ℓ1-ℓ1-optimization and Block Sparse Bayesian Learning (BSBL framework is presented to reconstruct the original bio-signals from the compressed bio-signals. The proposed architecture allows reducing the sampling rate to 25% of Nyquist Rate (NR. In addition, the proposed architecture reduces the power consumption to 40%, Percentage Residual Difference (PRD to 24%, Root Mean Squared Error (RMSE to 2%, and the computation time from 22 s to 9.01 s, which provide good background for establishing wearable wireless healthcare systems. The proposed architecture achieves robust performance in low Signal-to-Noise Ratio (SNR for the reconstruction process.

  19. Raft-based sphingomyelin interactions revealed by new fluorescent sphingomyelin analogs

    Science.gov (United States)

    Kinoshita, Masanao; Suzuki, Kenichi G.N.; Takada, Misa; Ano, Hikaru; Abe, Mitsuhiro; Makino, Asami; Kobayashi, Toshihide; Hirosawa, Koichiro M.; Fujiwara, Takahiro K.; Murata, Michio

    2017-01-01

    Sphingomyelin (SM) has been proposed to form cholesterol-dependent raft domains and sphingolipid domains in the plasma membrane (PM). How SM contributes to the formation and function of these domains remains unknown, primarily because of the scarcity of suitable fluorescent SM analogs. We developed new fluorescent SM analogs by conjugating a hydrophilic fluorophore to the SM choline headgroup without eliminating its positive charge, via a hydrophilic nonaethylene glycol linker. The new analogs behaved similarly to the native SM in terms of their partitioning behaviors in artificial liquid order-disorder phase-separated membranes and detergent-resistant PM preparations. Single fluorescent molecule tracking in the live-cell PM revealed that they indirectly interact with each other in cholesterol- and sphingosine backbone–dependent manners, and that, for ∼10–50 ms, they undergo transient colocalization-codiffusion with a glycosylphosphatidylinositol (GPI)-anchored protein, CD59 (in monomers, transient-dimer rafts, and clusters), in CD59-oligomer size–, cholesterol-, and GPI anchoring–dependent manners. These results suggest that SM continually and rapidly exchanges between CD59-associated raft domains and the bulk PM. PMID:28330937

  20. Production of Sulfur Allotropes in Electron Irradiated Jupiter Trojans Ice Analogs

    Science.gov (United States)

    Mahjoub, Ahmed; Poston, Michael J.; Blacksberg, Jordana; Eiler, John M.; Brown, Michael E.; Ehlmann, Bethany L.; Hodyss, Robert; Hand, Kevin P.; Carlson, Robert; Choukroun, Mathieu

    2017-09-01

    In this paper, we investigate sulfur chemistry in laboratory analogs of Jupiter Trojans and Kuiper Belt Objects (KBOs). Electron irradiation experiments of CH3OH-NH3-H2O and H2S-CH3OH-NH3-H2O ices were conducted to better understand the chemical differences between primordial planetesimals inside and outside the sublimation line of H2S. The main goal of this work is to test the chemical plausibility of the hypothesis correlating the color bimodality in Jupiter Trojans with sulfur chemistry in the incipient solar system. Temperature programmed desorption (TPD) of the irradiated mixtures allows the detection of small sulfur allotropes (S3 and S4) after the irradiation of H2S containing ice mixtures. These small, red polymers are metastable and could polymerize further under thermal processing and irradiation, producing larger sulfur polymers (mainly S8) that are spectroscopically neutral at wavelengths above 500 nm. This transformation may affect the spectral reflectance of Jupiter Trojans in a different way compared to KBOs, thereby providing a useful framework for possibly differentiating and determining the formation and history of small bodies. Along with allotropes, we report the production of organo-sulfur molecules. Sulfur molecules produced in our experiment have been recently detected by Rosetta in the coma of 67P/Churyumov-Gerasimenko. The very weak absorption of sulfur polymers in the infrared range hampers their identification on Trojans and KBOs, but these allotropes strongly absorb light at UV and Visible wavelengths. This suggests that high signal-to-noise ratio UV-Vis spectra of these objects could provide new constraints on their presence.

  1. Analysis and application of analog electronic circuits to biomedical instrumentation

    CERN Document Server

    Northrop, Robert B

    2003-01-01

    This book introduces the basic mathematical tools used to describe noise and its propagation through linear systems and provides a basic description of the improvement of signal-to-noise ratio by signal averaging and linear filtering. The text also demonstrates how op amps are the keystone of modern analog signal conditioning systems design, and illustrates their use in isolation and instrumentation amplifiers, active filters, and numerous biomedical instrumentation systems and subsystems. It examines the properties of the ideal op amp and applies this model to the analysis of various circuits

  2. Analogical Reasoning in Children with Specific Language Impairment

    Science.gov (United States)

    Leroy, Sandrine; Parisse, Christophe; Maillart, Christelle

    2012-01-01

    Usage-based theory considers analogical reasoning as a cognitive process required in language development. We hypothesized that difficulties with analogical reasoning could hinder the abstraction of construction schemas, thus slowing down morphosyntactic development for children with specific language impairment (SLI). We also hypothesized, in…

  3. Introduction to Electronics course

    CERN Multimedia

    CERN. Geneva HR-RFA

    2006-01-01

    Electronics in HEP experiments: specificities and evolution The Art of Electronics: is there something beyond Ohm's law? Basic building blocks of Analog electronics: quickly understanding a schematic Charge preamps, current preamps and future preamps, shaping and the rest Electronics noise: fundamental and practical Evolution of technology: ASICs, FPGAs...

  4. How to Implement an Experimental Course on Analog IC design in a Standard Semester Schedule

    DEFF Research Database (Denmark)

    Jørgensen, Ivan Harald Holger; Marker-Villumsen, Niels

    2013-01-01

    how the sequences of courses in integrated analog electronics at the Technical University of Denmark have been modified to enable this. It is outlined how a course can be designed using the three elements in constructive alignment: intended learning objectives, teaching activities and assessment....... As an example it is described in detail how a new course is designed. The course is the first of two new courses and the scope of the course is to teach the students the flow an IC designer has to go through when designing analog circuits. Additionally the course has a large focus on strengthening the generic...... engineering competences of the students. This is achieved by running the course as a project in a company with status meetings and a review meeting where the teacher acts as a manager. Finally, the course evaluation based on the Course Evaluation Questionnaire (CEQ) is presented and based on this future...

  5. Insulin analogs with improved pharmacokinetic profiles.

    Science.gov (United States)

    Brange; Vølund

    1999-02-01

    The aim of insulin replacement therapy is to normalize blood glucose in order to reduce the complications of diabetes. The pharmacokinetics of the traditional insulin preparations, however, do not match the profiles of physiological insulin secretion. The introduction of the rDNA technology 20 years ago opened new ways to create insulin analogs with altered properties. Fast-acting analogs are based on the idea that an insulin with less tendency to self-association than human insulin would be more readily absorbed into the systemic circulation. Protracted-acting analogs have been created to mimic the slow, steady rate of insulin secretion in the fasting state. The present paper provides a historical review of the efforts to change the physicochemical and pharmacological properties of insulin in order to improve insulin therapy. The available clinical studies of the new insulins are surveyed and show, together with modeling results, that new strategies for optimal basal-bolus treatment are required for utilization of the new fast-acting analogs.

  6. Chapter 9: Electronics

    International Nuclear Information System (INIS)

    Grupen, Claus; Shwartz, Boris A.

    2006-01-01

    Sophisticated front-end electronics are a key part of practically all modern radiation detector systems. This chapter introduces the basic principles and their implementation. Topics include signal acquisition, electronic noise, pulse shaping (analog and digital), and data readout techniques

  7. Neuroscientific Insights into the Development of Analogical Reasoning

    Science.gov (United States)

    Whitaker, Kirstie J.; Vendetti, Michael S.; Wendelken, Carter; Bunge, Silvia A.

    2018-01-01

    Analogical reasoning, or the ability to find correspondences between entities based on shared relationships, supports knowledge acquisition. As such, the development of this ability during childhood is thought to promote learning. Here, we sought to better understand the mechanisms by which analogical reasoning about semantic relations improves…

  8. Achiral Mannich-Base Curcumin Analogs Induce Unfolded Protein Response and Mitochondrial Membrane Depolarization in PANC-1 Cells

    Directory of Open Access Journals (Sweden)

    Gábor J. Szebeni

    2017-10-01

    Full Text Available Achiral Mannich-type curcumin analogs have been synthetized and assayed for their cytotoxic activity. The anti-proliferative and cytotoxic activity of curcuminoids has been tested on human non-small-cell lung carcinoma (A549, hepatocellular carcinoma (HepG2 and pancreatic cancer cell line (PANC-1. Based on the highest anti-proliferative activity nine drug candidates were further tested and proved to cause phosphatidylserine exposure as an early sign of apoptosis. Curcumin analogs with the highest apoptotic activity were selected for mechanistic studies in the most sensitive PANC-1 cells. Cytotoxic activity was accompanied by cytostatic effect since curcumin and analogs treatment led to G0/G1 cell cycle arrest. Moreover, cytotoxic effect could be also detected via the accumulation of curcuminoids in the endoplasmic reticulum (ER and the up-regulation of ER stress-related unfolded protein response (UPR genes: HSPA5, ATF4, XBP1, and DDIT3. The activated UPR induced mitochondrial membrane depolarization, caspase-3 activation and subsequent DNA breakdown in PANC-1 cells. Achiral curcumin analogs, C509, C521 and C524 possessed superior, 40-times more potent cytotoxic activity compared to natural dihydroxy-dimetoxycurcumin in PANC-1 cells.

  9. Achiral Mannich-Base Curcumin Analogs Induce Unfolded Protein Response and Mitochondrial Membrane Depolarization in PANC-1 Cells.

    Science.gov (United States)

    Szebeni, Gábor J; Balázs, Árpád; Madarász, Ildikó; Pócz, Gábor; Ayaydin, Ferhan; Kanizsai, Iván; Fajka-Boja, Roberta; Alföldi, Róbert; Hackler, László; Puskás, László G

    2017-10-07

    Achiral Mannich-type curcumin analogs have been synthetized and assayed for their cytotoxic activity. The anti-proliferative and cytotoxic activity of curcuminoids has been tested on human non-small-cell lung carcinoma (A549), hepatocellular carcinoma (HepG2) and pancreatic cancer cell line (PANC-1). Based on the highest anti-proliferative activity nine drug candidates were further tested and proved to cause phosphatidylserine exposure as an early sign of apoptosis. Curcumin analogs with the highest apoptotic activity were selected for mechanistic studies in the most sensitive PANC-1 cells. Cytotoxic activity was accompanied by cytostatic effect since curcumin and analogs treatment led to G₀/G₁ cell cycle arrest. Moreover, cytotoxic effect could be also detected via the accumulation of curcuminoids in the endoplasmic reticulum (ER) and the up-regulation of ER stress-related unfolded protein response (UPR) genes: HSPA5 , ATF4, XBP1 , and DDIT3 . The activated UPR induced mitochondrial membrane depolarization, caspase-3 activation and subsequent DNA breakdown in PANC-1 cells. Achiral curcumin analogs, C509, C521 and C524 possessed superior, 40-times more potent cytotoxic activity compared to natural dihydroxy-dimetoxycurcumin in PANC-1 cells.

  10. High-speed and high-resolution analog-to-digital and digital-to-analog converters

    NARCIS (Netherlands)

    van de Plassche, R.J.

    1989-01-01

    Analog-to-digital and digital-to-analog converters are important building blocks connecting the analog world of transducers with the digital world of computing, signal processing and data acquisition systems. In chapter two the converter as part of a system is described. Requirements of analog

  11. The possibilities of searching for new materials based on isocationic analogs of ZnBVI

    Science.gov (United States)

    Kirovskaya, I. A.; Mironova, E. V.; Kosarev, B. A.; Yureva, A. V.; Ekkert, R. V.

    2017-08-01

    Acid-base properties of chalcogenides - analogs of ZnBVI - were investigated in detail by modern techniques. The regularities of their composition-dependent changes were set, these regularities correlating with the dependencies "bulk physicochemical property - composition". The main reason for such correlations was found, facilitating the search for new materials of corresponding sensors. In this case, it was the sensors for basic gases impurities.

  12. A hierarchical spatiotemporal analog forecasting model for count data.

    Science.gov (United States)

    McDermott, Patrick L; Wikle, Christopher K; Millspaugh, Joshua

    2018-01-01

    Analog forecasting is a mechanism-free nonlinear method that forecasts a system forward in time by examining how past states deemed similar to the current state moved forward. Previous applications of analog forecasting has been successful at producing robust forecasts for a variety of ecological and physical processes, but it has typically been presented in an empirical or heuristic procedure, rather than as a formal statistical model. The methodology presented here extends the model-based analog method of McDermott and Wikle (Environmetrics, 27, 2016, 70) by placing analog forecasting within a fully hierarchical statistical framework that can accommodate count observations. Using a Bayesian approach, the hierarchical analog model is able to quantify rigorously the uncertainty associated with forecasts. Forecasting waterfowl settling patterns in the northwestern United States and Canada is conducted by applying the hierarchical analog model to a breeding population survey dataset. Sea surface temperature (SST) in the Pacific Ocean is used to help identify potential analogs for the waterfowl settling patterns.

  13. The use of analogy in pro-life argumentation

    Directory of Open Access Journals (Sweden)

    Simona Mazilu

    2012-11-01

    Full Text Available The paper is concerned with how analogy is strategically used in pro-life argumentation on abortion. Pragma-dialectics (van Eemeren and Grootendorst 1992 offers a set of critical questions by means of which I will evaluate the use of the argumentation based on a relation of analogy in terms of dialectical soundness. Examining various pro-life texts, I have noticed that the analogies employed remain unexplained. Therefore, despite the apparent similarities between abortion and the German holocaust or slavery, for instance, there are essential differences which are not mentioned. I claim that these analogies mainly have a rhetorical function, to operate what has been called by Micheli (2007: 960 “a transfer of emotional consensus”.

  14. Simulation of continuously logical base cells (CL BC) with advanced functions for analog-to-digital converters and image processors

    Science.gov (United States)

    Krasilenko, Vladimir G.; Lazarev, Alexander A.; Nikitovich, Diana V.

    2017-10-01

    The paper considers results of design and modeling of continuously logical base cells (CL BC) based on current mirrors (CM) with functions of preliminary analogue and subsequent analogue-digital processing for creating sensor multichannel analog-to-digital converters (SMC ADCs) and image processors (IP). For such with vector or matrix parallel inputs-outputs IP and SMC ADCs it is needed active basic photosensitive cells with an extended electronic circuit, which are considered in paper. Such basic cells and ADCs based on them have a number of advantages: high speed and reliability, simplicity, small power consumption, high integration level for linear and matrix structures. We show design of the CL BC and ADC of photocurrents and their various possible implementations and its simulations. We consider CL BC for methods of selection and rank preprocessing and linear array of ADCs with conversion to binary codes and Gray codes. In contrast to our previous works here we will dwell more on analogue preprocessing schemes for signals of neighboring cells. Let us show how the introduction of simple nodes based on current mirrors extends the range of functions performed by the image processor. Each channel of the structure consists of several digital-analog cells (DC) on 15-35 CMOS. The amount of DC does not exceed the number of digits of the formed code, and for an iteration type, only one cell of DC, complemented by the device of selection and holding (SHD), is required. One channel of ADC with iteration is based on one DC-(G) and SHD, and it has only 35 CMOS transistors. In such ADCs easily parallel code can be realized and also serial-parallel output code. The circuits and simulation results of their design with OrCAD are shown. The supply voltage of the DC is 1.8÷3.3V, the range of an input photocurrent is 0.1÷24μA, the transformation time is 20÷30nS at 6-8 bit binary or Gray codes. The general power consumption of the ADC with iteration is only 50÷100μW, if the

  15. Nemo-3 calorimeter electronics

    International Nuclear Information System (INIS)

    Bernaudin, P.; Cheikali, C.; Lavigne, B.; Richard, A.; Lebris, J.

    2000-11-01

    The calorimeter electronics of the NEMO-3 double beta decay experiment fulfills three functions: -energy measurement of the electrons by measuring the charge of the pulses, - time measurement, - fast first level triggering. The electronics of the 1940 Scintillator-PM modules is implemented as 40 '9U x 400 mm VME' boards of up to 51 channels. For each channel the analog signals conditioning is implemented as one SMD daughter board. Each board performs 12 bit charge measurements with 0.35 pC charge resolution, 12 bit time measurements with 50 ps time resolution and a fast analog multiplicity level for triggering. The total handling and conversion time for all the channels is less than 100 μs. The electronics will be presented as well as the test system. (authors)

  16. Production of Sulfur Allotropes in Electron Irradiated Jupiter Trojans Ice Analogs

    Energy Technology Data Exchange (ETDEWEB)

    Mahjoub, Ahmed; Poston, Michael J.; Blacksberg, Jordana; Ehlmann, Bethany L.; Hodyss, Robert; Hand, Kevin P.; Carlson, Robert; Choukroun, Mathieu [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Eiler, John M.; Brown, Michael E., E-mail: Mahjoub.Ahmed@jpl.nasa.gov [California Institute of Technology, Division of Geological and Planetary Sciences, Pasadena, CA 91125 (United States)

    2017-09-10

    In this paper, we investigate sulfur chemistry in laboratory analogs of Jupiter Trojans and Kuiper Belt Objects (KBOs). Electron irradiation experiments of CH{sub 3}OH–NH{sub 3}–H{sub 2}O and H{sub 2}S–CH{sub 3}OH–NH{sub 3}–H{sub 2}O ices were conducted to better understand the chemical differences between primordial planetesimals inside and outside the sublimation line of H{sub 2}S. The main goal of this work is to test the chemical plausibility of the hypothesis correlating the color bimodality in Jupiter Trojans with sulfur chemistry in the incipient solar system. Temperature programmed desorption (TPD) of the irradiated mixtures allows the detection of small sulfur allotropes (S{sub 3} and S{sub 4}) after the irradiation of H{sub 2}S containing ice mixtures. These small, red polymers are metastable and could polymerize further under thermal processing and irradiation, producing larger sulfur polymers (mainly S{sub 8}) that are spectroscopically neutral at wavelengths above 500 nm. This transformation may affect the spectral reflectance of Jupiter Trojans in a different way compared to KBOs, thereby providing a useful framework for possibly differentiating and determining the formation and history of small bodies. Along with allotropes, we report the production of organo-sulfur molecules. Sulfur molecules produced in our experiment have been recently detected by Rosetta in the coma of 67P/Churyumov–Gerasimenko. The very weak absorption of sulfur polymers in the infrared range hampers their identification on Trojans and KBOs, but these allotropes strongly absorb light at UV and Visible wavelengths. This suggests that high signal-to-noise ratio UV–Vis spectra of these objects could provide new constraints on their presence.

  17. Studying electron-PAG interactions using electron-induced fluorescence

    Science.gov (United States)

    Narasimhan, Amrit; Grzeskowiak, Steven; Ostrander, Jonathan; Schad, Jonathon; Rebeyev, Eliran; Neisser, Mark; Ocola, Leonidas E.; Denbeaux, Gregory; Brainard, Robert L.

    2016-03-01

    In extreme ultraviolet (EUV) lithography, 92 eV photons are used to expose photoresists. Typical EUV resists are organic-based and chemically amplified using photoacid generators (PAGs). Upon exposure, PAGs produce acids which catalyze reactions that result in changes in solubility. In EUV lithography, photo- and secondary electrons (energies of 10- 80 eV) play a large role in PAG acid-production. Several mechanisms for electron-PAG interactions (e.g. electron trapping, and hole-initiated chemistry) have been proposed. The aim of this study is to explore another mechanism - internal excitation - in which a bound PAG electron can be excited by receiving energy from another energetic electron, causing a reaction that produces acid. This paper explores the mechanism of internal excitation through the analogous process of electron-induced fluorescence, in which an electron loses energy by transferring that energy to a molecule and that molecule emits a photon rather than decomposing. We will show and quantify electron-induced fluorescence of several fluorophores in polymer films to mimic resist materials, and use this information to refine our proposed mechanism. Relationships between the molecular structure of fluorophores and fluorescent quantum yield may aid in the development of novel PAGs for EUV lithography.

  18. Photonic Beamformer Model Based on Analog Fiber-Optic Links’ Components

    International Nuclear Information System (INIS)

    Volkov, V A; Gordeev, D A; Ivanov, S I; Lavrov, A P; Saenko, I I

    2016-01-01

    The model of photonic beamformer for wideband microwave phased array antenna is investigated. The main features of the photonic beamformer model based on true-time-delay technique, DWDM technology and fiber chromatic dispersion are briefly analyzed. The performance characteristics of the key components of photonic beamformer for phased array antenna in the receive mode are examined. The beamformer model composed of the components available on the market of fiber-optic analog communication links is designed and tentatively investigated. Experimental demonstration of the designed model beamforming features includes actual measurement of 5-element microwave linear array antenna far-field patterns in 6-16 GHz frequency range for antenna pattern steering up to 40°. The results of experimental testing show good accordance with the calculation estimates. (paper)

  19. Using Analogies to Prevent Misconceptions about Chemical Equilibrium

    Science.gov (United States)

    Sahin Pekmez, Esin

    2010-01-01

    The main purpose of this study was to find the effectiveness of using analogies to prevent misconceptions about chemical equilibrium. Nineteen analogies, which were based on dynamic aspects of chemical equilibrium and application of Le Chatelier's principle, were developed. The participations of this study consisted of 11th grade students (n: 151)…

  20. Design and implementation of a reconfigurable mixed-signal SoC based on field programmable analog arrays

    Science.gov (United States)

    Liu, Lintao; Gao, Yuhan; Deng, Jun

    2017-11-01

    This work presents a reconfigurable mixed-signal system-on-chip (SoC), which integrates switched-capacitor-based field programmable analog arrays (FPAA), analog-to-digital converter (ADC), digital-to-analog converter, digital down converter , digital up converter, 32-bit reduced instruction-set computer central processing unit (CPU) and other digital IPs on a single chip with 0.18 μm CMOS technology. The FPAA intellectual property could be reconfigured as different function circuits, such as gain amplifier, divider, sine generator, and so on. This single-chip integrated mixed-signal system is a complete modern signal processing system, occupying a die area of 7 × 8 mm 2 and consuming 719 mW with a clock frequency of 150 MHz for CPU and 200 MHz for ADC/DAC. This SoC chip can help customers to shorten design cycles, save board area, reduce the system power consumption and depress the system integration risk, which would afford a big prospect of application for wireless communication. Project supported by the National High Technology and Development Program of China (No. 2012AA012303).

  1. Design of simulated nuclear electronics laboratory experiments based on IAEA-TECDOC-530 on pcs

    International Nuclear Information System (INIS)

    Ghousia, S.F.; Nadeem, M.; Khaleeq, M.T.

    2002-05-01

    In this IAEA project, PK-11089 (Design of Simulated Nuclear Electronics Laboratory Experiments based on IAEA-TECDOC-530 on PCs), a software package consisting of Computer-Simulated Laboratory Experiments on Nuclear Electronics compatible with the IAEA-TECDOC-530 (Nuclear Electronics Laboratory Manual) has been developed in OrCAD 9.0 (an electronic circuit simulation software environment) as a self-training aid. The software process model employed in this project is the Feedback Waterfall model with some Rapid Application Model. The project work is completed in the five phases of the SDLC, (all of them have been fully completed) which includes the Requirement Definition, Phase, System and Software Design, Implementation and Unit testing, Integration and System-testing phase and the Operation and Maintenance phase. A total of 125 circuits are designed in 39 experiments from Power Supplies, Analog circuits, Digital circuits and Multi-channel analyzer sections. There is another set of schematic designs present in the package, which contains faulty circuits. This set is designed for the learners to exercise the troubleshooting. The integration and system-testing phase was carried out simultaneously. The Operation and Maintenance phase has been implemented by accomplishing it through some trainees and some undergraduate engineering students by allowing them to play with the software independently. (author)

  2. Diagnostic Neural Network Systems for the Electronic Circuits

    International Nuclear Information System (INIS)

    Mohamed, A.H.

    2014-01-01

    Neural Networks is one of the most important artificial intelligent approaches for solving the diagnostic processes. This research concerns with uses the neural networks for diagnosis of the electronic circuits. Modern electronic systems contain both the analog and digital circuits. But, diagnosis of the analog circuits suffers from great complexity due to their nonlinearity. To overcome this problem, the proposed system introduces a diagnostic system that uses the neural network to diagnose both the digital and analog circuits. So, it can face the new requirements for the modern electronic systems. A fault dictionary method was implemented in the system. Experimental results are presented on three electronic systems. They are: artificial kidney, wireless network and personal computer systems. The proposed system has improved the performance of the diagnostic systems when applied for these practical cases

  3. Nonequilibrium Transport and the Bernoulli Effect of Electrons in a Two-Dimensional Electron Gas

    Science.gov (United States)

    Kaya, Ismet I.

    2013-02-01

    Nonequilibrium transport of charged carriers in a two-dimensional electron gas is summarized from an experimental point of view. The transport regime in which the electron-electron interactions are enhanced at high bias leads to a range of striking effects in a two-dimensional electron gas. This regime of transport is quite different than the ballistic transport in which particles propagate coherently with no intercarrier energy transfer and the diffusive transport in which the momentum of the electron system is lost with the involvement of the phonons. Quite a few hydrodynamic phenomena observed in classical gasses have the electrical analogs in the current flow. When intercarrier scattering events dominate the transport, the momentum sharing via narrow angle scattering among the hot and cold electrons lead to negative resistance and electron pumping which can be viewed as the analog of the Bernoulli-Venturi effect observed classical gasses. The recent experimental findings and the background work in the field are reviewed.

  4. Designing charge-sensitive preamplifiers based on low-noise analog integrated circuits

    International Nuclear Information System (INIS)

    Agakhanyan, T.M.

    1998-01-01

    The methodology for designing charge-sensitive preamplifiers on the low-noise analog integral circuits, including all the stages: the mathematical synthesis with optimization of the intermediate function; the scheme-technical synthesis with parametric optimization of the scheme and analysis of draft projects with the parameter verification is presented. The designing is conducted on the basis of requirements for signal parameters and noise indices of the preamplifier. The system of automated designing of the charge-sensitive preamplifiers on the low-noise analog integral circuits is developed [ru

  5. Model, analysis, and evaluation of the effects of analog VLSI arithmetic on linear subspace-based image recognition.

    Science.gov (United States)

    Carvajal, Gonzalo; Figueroa, Miguel

    2014-07-01

    Typical image recognition systems operate in two stages: feature extraction to reduce the dimensionality of the input space, and classification based on the extracted features. Analog Very Large Scale Integration (VLSI) is an attractive technology to achieve compact and low-power implementations of these computationally intensive tasks for portable embedded devices. However, device mismatch limits the resolution of the circuits fabricated with this technology. Traditional layout techniques to reduce the mismatch aim to increase the resolution at the transistor level, without considering the intended application. Relating mismatch parameters to specific effects in the application level would allow designers to apply focalized mismatch compensation techniques according to predefined performance/cost tradeoffs. This paper models, analyzes, and evaluates the effects of mismatched analog arithmetic in both feature extraction and classification circuits. For the feature extraction, we propose analog adaptive linear combiners with on-chip learning for both Least Mean Square (LMS) and Generalized Hebbian Algorithm (GHA). Using mathematical abstractions of analog circuits, we identify mismatch parameters that are naturally compensated during the learning process, and propose cost-effective guidelines to reduce the effect of the rest. For the classification, we derive analog models for the circuits necessary to implement Nearest Neighbor (NN) approach and Radial Basis Function (RBF) networks, and use them to emulate analog classifiers with standard databases of face and hand-writing digits. Formal analysis and experiments show how we can exploit adaptive structures and properties of the input space to compensate the effects of device mismatch at the application level, thus reducing the design overhead of traditional layout techniques. Results are also directly extensible to multiple application domains using linear subspace methods. Copyright © 2014 Elsevier Ltd. All rights

  6. READ - Remote Analog ASIC Design System

    Directory of Open Access Journals (Sweden)

    Michael E. Auer

    2006-11-01

    Full Text Available The scope of this work is to present a solution to implement a remote electronic laboratory for testing and designing analog ASICs (ispPAC10. The application allows users to create circuit schematics, upload the design to the device and perform measurements. The software used for designing circuits is the PAC-Designer and it runs on a Citrix server. The signals are generated and the responses are acquired by a data acquisition board controlled by LabView. The virtual instruments interact with some ActiveX controls specially designed to look like real oscilloscope and function generator devices and represent the user interface of the lab. These ActiveX give users the control over the LabView VIs and the access to its facilities in order to perform electronic exercises.

  7. IADE: a system for intelligent automatic design of bioisosteric analogs

    Science.gov (United States)

    Ertl, Peter; Lewis, Richard

    2012-11-01

    IADE, a software system supporting molecular modellers through the automatic design of non-classical bioisosteric analogs, scaffold hopping and fragment growing, is presented. The program combines sophisticated cheminformatics functionalities for constructing novel analogs and filtering them based on their drug-likeness and synthetic accessibility using automatic structure-based design capabilities: the best candidates are selected according to their similarity to the template ligand and to their interactions with the protein binding site. IADE works in an iterative manner, improving the fitness of designed molecules in every generation until structures with optimal properties are identified. The program frees molecular modellers from routine, repetitive tasks, allowing them to focus on analysis and evaluation of the automatically designed analogs, considerably enhancing their work efficiency as well as the area of chemical space that can be covered. The performance of IADE is illustrated through a case study of the design of a nonclassical bioisosteric analog of a farnesyltransferase inhibitor—an analog that has won a recent "Design a Molecule" competition.

  8. MX chains: 1-D analog of CuO planes?

    International Nuclear Information System (INIS)

    Gammel, J.T.; Batistic, I.; Bishop, A.R.; Loh, E.Y. Jr.; Marianer, S.

    1989-01-01

    We study a two-band Peierls-Hubbard model for halogen-bridged mixed-valence transition metal linear chain complexes (MX chains). We include electron-electron correlations (both Hubbard and PPP-like expressions) using several techniques including calculations in the zero-hopping limit, exact diagonalization of small systems, mean field approximation, and a Gutzwiller-like Ansatz for quantum phonons. The adiabatic optical absorption and phonon spectra for both photo-excited and doping induced defects (kinks, polarons, bipolarons, and excitons) are discussed. A long period phase which occurs even at commensurate filling for certain parameter values may be related to twinning. The effect of including the electron-phonon in addition to the electron-electron interaction on the polaron/bipolaron (pairing) competition is especially interesting when this class of compounds is viewed as a 1-D analog of high-temperature superconductors. 6 refs., 4 figs

  9. 22nd Workshop on Advances in Analog Circuit Design

    CERN Document Server

    Makinwa, Kofi; Harpe, Pieter

    2014-01-01

    This book is based on the 18 tutorials presented during the 22nd workshop on Advances in Analog Circuit Design.  Expert designers present readers with information about a variety of topics at the frontier of analog circuit design, including frequency reference, power management for systems-on-chip, and smart wireless interfaces.  This book serves as a valuable reference to the state-of-the-art, for anyone involved in analog circuit research and development.    ·         Provides a state-of-the-art reference in analog circuit design, written by experts from industry and academia; ·         Presents material in a tutorial-based format; ·         Includes coverage of frequency reference, power management for systems-on-chip, and smart wireless interfaces.

  10. VME Switch for CERN's PS Analog Video System

    CERN Document Server

    Acebes, I; Heinze, W; Lewis, J; Serrano, J

    2003-01-01

    Analog video signal switching is used in CERN's Proton Synchrotron (PS) complex to route the video signals coming from Beam Diagnostics systems to the Meyrin Control Room (MCR). Traditionally, this has been done with custom electromechanical relay-based cards controlled serially via CAMAC crates. In order to improve the robustness and maintainability of the system, while keeping it analog to preserve the low latency, a VME card based on Analog Devices' AD8116 analog matrix chip has been developed. Video signals go into the front panel and exit the switch through the P2 connector of the VME backplane. The module is a 16 input, 32 output matrix. Larger matrices can be built using more modules and bussing their outputs together, thanks to the high impedance feature of the AD8116. Another VME module takes the selected signals from the P2 connector and performs automatic gain to send them at nominal output level through its front panel. This paper discusses both designs and presents experimental test results.

  11. MaMBA - a functional Moon and Mars Base Analog

    Science.gov (United States)

    Heinicke, C.; Foing, B.

    2017-09-01

    Despite impressive progress in robotic exploration of celestial bodies, robots are believed to never reach the effectiveness and efficiency of a trained human. Consequently, ESA proposes to build an international Moon Village in roughly 15 years and NASA plans for the first manned mission to Mars shortly after. One of the challenges still remaining is the need for a shelter, a habitat which allows human spacefarers to safely live and work on the surface of a celestial body. Although a number of prototype habitats has been built during the last decades and inhabited for various durations (e.g. MDRS, FMARS, HI-SEAS, M.A.R.S.), these habitats are typically equipped for studies on human factors and would not function in an extraterrestrial environment. Project MaMBA (Moon and Mars Base Analog) aims to build the first functional habitat based on the lessons learned from intermediate and long duration missions at the mentioned habitats. The habitat will serve for testing technologies like life support, power systems, and interplanetary communi­cation. Special attention will be given to the develop­ment of the geoscience laboratory module. Crews will live and work inside the habitat to ensure its functionality.

  12. An integrated analog O/E/O link for multi-channel laser neurons

    Energy Technology Data Exchange (ETDEWEB)

    Nahmias, Mitchell A., E-mail: mnahmias@princeton.edu; Tait, Alexander N.; Tolias, Leonidas; Chang, Matthew P.; Ferreira de Lima, Thomas; Shastri, Bhavin J.; Prucnal, Paul R. [Electrical Engineering Department, Princeton University, 41 Olden St, Princeton, New Jersey 08540 (United States)

    2016-04-11

    We demonstrate an analog O/E/O electronic link to allow integrated laser neurons to accept many distinguishable, high bandwidth input signals simultaneously. This device utilizes wavelength division multiplexing to achieve multi-channel fan-in, a photodetector to sum signals together, and a laser cavity to perform a nonlinear operation. Its speed outpaces accelerated-time neuromorphic electronics, and it represents a viable direction towards scalable networking approaches.

  13. Analog earthquakes

    International Nuclear Information System (INIS)

    Hofmann, R.B.

    1995-01-01

    Analogs are used to understand complex or poorly understood phenomena for which little data may be available at the actual repository site. Earthquakes are complex phenomena, and they can have a large number of effects on the natural system, as well as on engineered structures. Instrumental data close to the source of large earthquakes are rarely obtained. The rare events for which measurements are available may be used, with modfications, as analogs for potential large earthquakes at sites where no earthquake data are available. In the following, several examples of nuclear reactor and liquified natural gas facility siting are discussed. A potential use of analog earthquakes is proposed for a high-level nuclear waste (HLW) repository

  14. Multisensor transducer based on a parallel fiber optic digital-to-analog converter

    Directory of Open Access Journals (Sweden)

    Grechishnikov Vladimir

    2017-01-01

    Full Text Available Considered possibility of creating a multisensory information converter (MSPI based on new fiber-optic functional element-digital-to-analog (DAC fiber optic converter. The use of DAC fiber-optic provides jamming immunity combined with low weight and cost of indicators .Because of that MSPI scheme was developed based on parallel DAC fiber-optic (Russian Federation Patent 157416. We came up with an equation for parallel DAC fiber-optic. An eleborate general mathematical model of the proposed converter. Developed a method for reducing conversion errors by placing the DAC transfer function between i and i + 1 ADC quantization levels. By using this model it allows you to obtain reliable information about the technical capabilities of a converter without the need for costly experiments.

  15. Potentialities in electronics of new high critical temperature superconductors

    International Nuclear Information System (INIS)

    Hartemann, P.

    1989-01-01

    The main electronic applications of superconductors involve the signal processing, the electromagnetic wave detection and the magnetometry. Characteristics of devices based on conventional superconductors cooled by liquid helium are given and the changes induced by incorporating high-temperature superconductors are estimated. After a survey of new superconductor properties, the superconducting devices for analog or digital signal processing are reviewed. The gains predicted for high-temperature superconducting analog devices are considered in greater detail. Different sections deal with the infrared or (sub)millimeter wave detection. The most sensitive apparatuses for magnetic measurements are based on SQUIDs. Features of SQUIDs made of granular high-temperature superconducting material samples (grain boundaries behave as barriers of intrinsic junctions) are discussed [fr

  16. Reasoning by analogy as an aid to heuristic theorem proving.

    Science.gov (United States)

    Kling, R. E.

    1972-01-01

    When heuristic problem-solving programs are faced with large data bases that contain numbers of facts far in excess of those needed to solve any particular problem, their performance rapidly deteriorates. In this paper, the correspondence between a new unsolved problem and a previously solved analogous problem is computed and invoked to tailor large data bases to manageable sizes. This paper outlines the design of an algorithm for generating and exploiting analogies between theorems posed to a resolution-logic system. These algorithms are believed to be the first computationally feasible development of reasoning by analogy to be applied to heuristic theorem proving.

  17. 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. <

  18. Optical analogy. Synthesis report

    International Nuclear Information System (INIS)

    1965-01-01

    The authors report the study of conditions under which light attenuation (reflection, diffusion, absorption) and the attenuation of some radiations (notably thermal neutrons) can be described with analogical calculations. The analogy between light physical properties and neutron properties is not searched for, but the analogy between their attenuation characteristics. After having discussed this possible analogy, they propose a mathematical formulation of neutron and optical phenomena which could theoretically justify the optical analogy. The second part reports a more practical study of optics problems such as the study of simple optics materials and illumination measurements, or more precisely the study of angular distributions of optical reflections, a determination of such angular distributions, and an experimental determination of the albedo

  19. Electronics for Guitarists

    CERN Document Server

    Dailey, Denton J

    2013-01-01

    In the second edition of Electronics for Guitarists author Denton Dailey teaches the basic theory of operation and design principles of analog guitar signal processing circuits and amplifiers. The design and operation of common effects circuits such as tone controls, preamps, phasers, flangers, envelope followers, distortion and overdrives are covered, as are both solid-state amplifiers and power supplies. Written primarily for the guitarist, this book balances coverage of theoretical analysis and design while providing many examples of practical experimental circuits. The main thrust of the material is analog circuitry, focusing on fundamental principles of transistors, integrated circuit and vacuum tube-based amplifier operation and theory, and operation of typical guitar signal processing effects circuits. Updated to the new edition include: • New coverage of tone control circuits, MOSFETS and their applications as small-signal amplifiers, rail splitters and charge pumps, amplifiers using germanium trans...

  20. Using analog instruments in Tracker video-based experiments to understand the phenomena of electricity and magnetism in physics education

    Science.gov (United States)

    Aguilar-Marín, Pablo; Chavez-Bacilio, Mario; Jáuregui-Rosas, Segundo

    2018-05-01

    Tracker is a piece of freeware software, designed to use video recorded images of the motion of objects as input data, and has been mostly applied in physics education to analyse and simulate physical phenomena in mechanics. In this work we report the application of Tracker to the study of experiments in electricity and magnetism using analog instruments for electrical signal measurements. As we are unable to directly video-track the motion of electrons in electric circuits, the angular deflections of the instruments’ pointers were video captured instead. The kinematic variables (angular position as a function of time) had to be related to the electrical ones (voltages and currents as a function of time). Two well-known experiments in physics teaching, the RC circuit for charging and discharging a capacitor and Faraday electromagnetic induction, were chosen to illustrate the procedures. The third experiment analysed and modeled with Tracker was the rather well-known electromagnetic retardation of disk- or cylinder-shaped magnets falling inside non-magnetic metallic pipes. Instead of metallic pipes we used an aluminum plate with an arrangement of a couple of parallelepiped-shaped magnets falling parallel to the plate. In the three cases studied, the experimental and the Tracker simulation results were in very good agreement. These outcomes show that it is possible to exploit the potential of Tracker software in areas other than mechanics, in areas where electrical signals are involved. The experiments are inexpensive and simple to perform, and are suitable for high school and introductory undergraduate courses in electricity, magnetism and electronics. We propose the use of Tracker combined with analog measuring devices to explore further its applications in electricity, magnetism, electronics and in other experimental sciences where electrical signals are involved.

  1. Supporting Analogy-based Effort Estimation with the Use of Ontologies

    Directory of Open Access Journals (Sweden)

    Joanna Kowalska

    2014-06-01

    Full Text Available The paper concerns effort estimation of software development projects, in particular, at the level of product delivery stages. It proposes a new approach to model project data to support expert-supervised analogy-based effort estimation. The data is modeled using Semantic Web technologies, such as Resource Description Framework (RDF and Ontology Language for the Web (OWL. Moreover, in the paper, we define a method of supervised case-based reasoning. The method enables to search for similar projects’ tasks at different levels of abstraction. For instance, instead of searching for a task performed by a specific person, one could look for tasks performed by people with similar capabilities. The proposed method relies on ontology that defines the core concepts and relationships. However, it is possible to introduce new classes and relationships, without the need of altering the search mechanisms. Finally, we implemented a prototype tool that was used to preliminary validate the proposed approach. We observed that the proposed approach could potentially help experts in estimating non-trivial tasks that are often underestimated.

  2. Bayesian analogy with relational transformations.

    Science.gov (United States)

    Lu, Hongjing; Chen, Dawn; Holyoak, Keith J

    2012-07-01

    How can humans acquire relational representations that enable analogical inference and other forms of high-level reasoning? Using comparative relations as a model domain, we explore the possibility that bottom-up learning mechanisms applied to objects coded as feature vectors can yield representations of relations sufficient to solve analogy problems. We introduce Bayesian analogy with relational transformations (BART) and apply the model to the task of learning first-order comparative relations (e.g., larger, smaller, fiercer, meeker) from a set of animal pairs. Inputs are coded by vectors of continuous-valued features, based either on human magnitude ratings, normed feature ratings (De Deyne et al., 2008), or outputs of the topics model (Griffiths, Steyvers, & Tenenbaum, 2007). Bootstrapping from empirical priors, the model is able to induce first-order relations represented as probabilistic weight distributions, even when given positive examples only. These learned representations allow classification of novel instantiations of the relations and yield a symbolic distance effect of the sort obtained with both humans and other primates. BART then transforms its learned weight distributions by importance-guided mapping, thereby placing distinct dimensions into correspondence. These transformed representations allow BART to reliably solve 4-term analogies (e.g., larger:smaller::fiercer:meeker), a type of reasoning that is arguably specific to humans. Our results provide a proof-of-concept that structured analogies can be solved with representations induced from unstructured feature vectors by mechanisms that operate in a largely bottom-up fashion. We discuss potential implications for algorithmic and neural models of relational thinking, as well as for the evolution of abstract thought. Copyright 2012 APA, all rights reserved.

  3. Paper based electronics platform

    KAUST Repository

    Nassar, Joanna Mohammad; Sevilla, Galo Andres Torres; Hussain, Muhammad Mustafa

    2017-01-01

    A flexible and non-functionalized low cost paper-based electronic system platform fabricated from common paper, such as paper based sensors, and methods of producing paper based sensors, and methods of sensing using the paper based sensors

  4. Human Health Countermeasures - Partial-Gravity Analogs Workshop

    Science.gov (United States)

    Barr, Yael; Clement, Gilles; Norsk, Peter

    2016-01-01

    The experimental conditions that were deemed the most interesting by the HHC Element lead scientists are those permitting studies of the long-term effects of exposure to (a) chronic rotation when supine or in head down tilt (ground-based); and (b) long-radius centrifugation (space based). It is interesting to note that chronic ground based slow rotation room studies have not been performed since the 1960's, when the USA and USSR were investigating the potential use of AG for long-duration space missions. On the other hand, the other partial gravity analogs, i.e., parabolic flight, HUT, suspension, and short-radius centrifugation, have been regularly used in the last three decades (see review in Clément et al. 2015). Based on the workshop evaluations and the scores by the HHC scientific disciplines indicated in tables 3 and 4, simulation of partial G between 0 and 1 should be prioritized as follows: Priority 1. Chronic space-based partial-G analogs: a. Chronic space-based long-radius centrifugation. The ideal scenario would be chronic long-radius centrifugation of cells, animals and humans in a translational research approach - ideally beyond low earth orbit under deep space environmental effects and at various rotations - to obtain different G-effects. In this scenario, all physiological systems could be evaluated and the relationship between physiological response and G level established. This would be the most integrative way of defining, for the first time ever, G-thresholds for each physiological system. b. Chronic space-based centrifugation of animals. Chronic centrifugation of rodents at various G levels in space would allow for determination of AG thresholds of protection for each physiological system. In this case, all physiological systems will be of interest. Intermittent centrifugation will be of secondary interest. c. Chronic space-based centrifugation of cell cultures (RWV). Bioreactor studies of cells and cell cultures of various tissues at various G

  5. Leibniz y el concepto de analogía

    Directory of Open Access Journals (Sweden)

    Oscar Miguel Esquisabel

    2008-11-01

    Full Text Available In this paper an analysis of the leibnizian applications of conceptof analogy as well as the analogical reasoning is approached. Thus, the analysis tries to show that the leibnizian concept of analogy is based on the idea of structural similarity. As a consequence of such consideration,two basic ways in which Leibniz applies analogical reasoning are examined. The first way has a conjectural character and is rather heuristic, whereas the second constitutes, at least in intention, a kind of demonstrative analogicalreasoning, since it tries to prove its conclusions for a determined theoreticaldomain by applying a transfer principle, which is itself founded on the identity of structural properties.This procedure is exemplified by outlining the leibnizian view on contingent truths. In this way, the paper concludesby pointing out the theoretical relevance of the concept of similarity in theleibnizian thought.

  6. Analogical Reasoning in Geometry Education

    Science.gov (United States)

    Magdas, Ioana

    2015-01-01

    The analogical reasoning isn't used only in mathematics but also in everyday life. In this article we approach the analogical reasoning in Geometry Education. The novelty of this article is a classification of geometrical analogies by reasoning type and their exemplification. Our classification includes: analogies for understanding and setting a…

  7. Nyquist AD Converters, Sensor Interfaces, and Robustness Advances in Analog Circuit Design, 2012

    CERN Document Server

    Baschirotto, Andrea; Steyaert, Michiel

    2013-01-01

    This book is based on the presentations during the 21st workshop on Advances in Analog Circuit Design.  Expert designers provide readers with information about a variety of topics at the frontier of analog circuit design, including Nyquist analog-to-digital converters, capacitive sensor interfaces, reliability, variability, and connectivity.  This book serves as a valuable reference to the state-of-the-art, for anyone involved in analog circuit research and development.  Provides a state-of-the-art reference in analog circuit design, written by experts from industry and academia; Presents material in a tutorial-based format; Includes coverage of Nyquist A/D converters, capacitive sensor interfaces, reliability, variability, and connectivity.

  8. Regulation of the Contribution of Integrin to Cell Attachment on Poly(2-Methoxyethyl Acrylate (PMEA Analogous Polymers for Attachment-Based Cell Enrichment.

    Directory of Open Access Journals (Sweden)

    Takashi Hoshiba

    Full Text Available Cell enrichment is currently in high demand in medical engineering. We have reported that non-blood cells can attach to a blood-compatible poly(2-methoxyethyl acrylate (PMEA substrate through integrin-dependent and integrin-independent mechanisms because the PMEA substrate suppresses protein adsorption. Therefore, we assumed that PMEA analogous polymers can change the contribution of integrin to cell attachment through the regulation of protein adsorption. In the present study, we investigated protein adsorption, cell attachment profiles, and attachment mechanisms on PMEA analogous polymer substrates. Additionally, we demonstrated the possibility of attachment-based cell enrichment on PMEA analogous polymer substrates. HT-1080 and MDA-MB-231 cells started to attach to poly(butyl acrylate (PBA and poly(tetrahydrofurfuryl acrylate (PTHFA, on which proteins could adsorb well, within 1 h. HepG2 cells started to attach after 1 h. HT-1080, MDA-MB-231, and HepG2 cells started to attach within 30 min to PMEA, poly(2-(2-methoxyethoxy ethyl acrylate-co-butyl acrylate (30:70 mol%, PMe2A and poly(2-(2-methoxyethoxy ethoxy ethyl acrylate-co-butyl acrylate (30:70 mol%, PMe3A, which suppress protein adsorption. Moreover, the ratio of attached cells from a cell mixture can be changed on PMEA analogous polymers. These findings suggested that PMEA analogous polymers can be used for attachment-based cell enrichment.

  9. The making of analog module for gamma camera interface

    International Nuclear Information System (INIS)

    Yulinarsari, Leli; Rl, Tjutju; Susila, Atang; Sukandar

    2003-01-01

    The making of an analog module for gamma camera has been conducted. For computerization of planar gamma camera 37 PMT it has been developed interface hardware technology and software between the planar gamma camera with PC. With this interface gamma camera image information (Originally analog signal) was changed to digital single, therefore processes of data acquisition, image quality increase and data analysis as well as data base processing can be conducted with the help of computers, there are three gamma camera main signals, i.e. X, Y and Z . This analog module makes digitation of analog signal X and Y from the gamma camera that conveys position information coming from the gamma camera crystal. Analog conversion to digital was conducted by 2 converters ADC 12 bit with conversion time 800 ns each, conversion procedure for each coordinate X and Y was synchronized using suitable strobe signal Z for information acceptance

  10. Synthesis of Novel Homo-N-Nucleoside Analogs Composed of a Homo-1,4-Dioxane Sugar Analog and Substituted 1,3,5-Triazine Base Equivalents

    Directory of Open Access Journals (Sweden)

    Qiang Yu

    2008-12-01

    Full Text Available Enantioselective syntheses from dimethyl tartrate of 1,3,5-triazine homo-N-nucleoside analogs, containing a 1,4-dioxane moiety replacing the sugar unit in natural nucleosides, were accomplished. The triazine heterocycle in the nucleoside analogs was further substituted with combinations of NH2, OH and Cl in the 2,4-triazine positions.

  11. Analogy Mapping Development for Learning Programming

    Science.gov (United States)

    Sukamto, R. A.; Prabawa, H. W.; Kurniawati, S.

    2017-02-01

    Programming skill is an important skill for computer science students, whereas nowadays, there many computer science students are lack of skills and information technology knowledges in Indonesia. This is contrary with the implementation of the ASEAN Economic Community (AEC) since the end of 2015 which is the qualified worker needed. This study provided an effort for nailing programming skills by mapping program code to visual analogies as learning media. The developed media was based on state machine and compiler principle and was implemented in C programming language. The state of every basic condition in programming were successful determined as analogy visualization.

  12. Microscopy of electronic wave function

    International Nuclear Information System (INIS)

    Harb, M.

    2010-01-01

    This work of thesis aims to visualize, on a position sensitive detector, the spatial oscillations of slow electrons (∼ meV) emitted by a threshold photoionization in the presence of an external electric field. The interference figure obtained represents the square magnitude of electronic wavefunction. This fundamental work allows us to have access to the electronic dynamics and thus to highlight several quantum mechanisms that occur at the atomic scale (field Coulomb, electron/electron interaction..). Despite the presence an electronic core in Li atom, we have succeeded, experimentally and for the first time, in visualizing the wave function associated with the quasi-discrete Stark states coupled to the ionization continuum. Besides, using simulations of wave packet propagation, based on the 'Split-operator' method, we have conducted a comprehensive study of the H, Li and Cs atoms while revealing the significant effects of the Stark resonances. A very good agreement, on and off resonances, was obtained between simulated and experimental results. In addition, we have developed a generalized analytical model to understand deeply the function of VMI (Velocity-Map Imaging) spectrometer. This model is based on the paraxial approximation; it is based on matrix optics calculation by making an analogy between the electronic trajectory and the light beam. An excellent agreement was obtained between the model predictions and the experimental results. (author)

  13. Rubrolides as model for the development of new lactones and their aza analogs as potential photosynthesis inhibitors.

    Science.gov (United States)

    Pereira, Ulisses A; Barbosa, Luiz C A; Demuner, Antônio J; Silva, Antônio A; Bertazzini, Michele; Forlani, Giuseppe

    2015-07-01

    Natural phytotoxins and their synthetic analogs are a potential source of new bioactive compounds for agriculture. Analogs of rubrolides, a class of γ-alkylidene-γ-lactones isolated from different ascidians, have been shown to interfere with the photosynthetic electron-transport chain, yet their activity needs to be improved. With this aim, ten 5-aryl-6-benzyl-4-bromopyridazin-3(2H)-ones were prepared in yields ranging from 44 to 88% by reaction of their correspondent γ-alkylidene-γ-lactones with NH2 NH2 . The structures of these rubrolide analogs were determined by (1) H- and (13) C-NMR, 2D-NMR (COSY and HETCOR), NOE difference, and MS techniques. These compounds were evaluated for their abilities of interfering with the light-driven reduction of ferricyanide by isolated spinach chloroplasts. Lactones with electron-withdrawing substituents in the para-position of the benzylidene ring were the most effective inhibitors. Characterization of the activity of 11b/11b' suggested a mechanism based on the interaction with the plastoquinone binding site of photosystem II. Addition of several compounds to the culture medium of a cyanobacterial model strain was found to inhibit algal growth. However, the relative effectiveness was not consistent with their activity in vitro, suggesting the occurrence of multiple targets and/or detoxyfication mechanisms. Indeed, the compounds showed differential effects on the heterotrophic growth of some crop species, Cucumis sativus and Sorghum bicolor. Pyridazin-3(2H)-ones 12e, 12i, and 12j, which have been found poorly active against the photosynthetic electron transport, were the most effective in inhibiting the growth of some weeds, Ipomoea grandifolia and Brachiaria decumbens, under greenhouse conditions. Copyright © 2015 Verlag Helvetica Chimica Acta AG, Zürich.

  14. Analog circuit design a tutorial guide to applications and solutions

    CERN Document Server

    Williams, Jim

    2011-01-01

    * Covers the fundamentals of linear/analog circuit and system design to guide engineers with their design challenges. * Based on the Application Notes of Linear Technology, the foremost designer of high performance analog products, readers will gain practical insights into design techniques and practice. * Broad range of topics, including power management tutorials, switching regulator design, linear regulator design, data conversion, signal conditioning, and high frequency/RF design. * Contributors include the leading lights in analog design, Robert Dobkin, Jim Willia

  15. Meat analog: a review.

    Science.gov (United States)

    Malav, O P; Talukder, S; Gokulakrishnan, P; Chand, S

    2015-01-01

    The health-conscious consumers are in search of nutritious and convenient food item which can be best suited in their busy life. The vegetarianism is the key for the search of such food which resembles the meat in respect of nutrition and sensory characters, but not of animal origin and contains vegetable or its modified form, this is the point when meat analog evolved out and gets shape. The consumers gets full satisfaction by consumption of meat analog due to its typical meaty texture, appearance and the flavor which are being imparted during the skilled production of meat analog. The supplement of protein in vegetarian diet through meat alike food can be fulfilled by incorporating protein-rich vegetative food grade materials in meat analog and by adopting proper technological process which can promote the proper fabrication of meat analog with acceptable meat like texture, appearance, flavor, etc. The easily available vegetables, cereals, and pulses in India have great advantages and prospects to be used in food products and it can improve the nutritional and functional characters of the food items. The various form and functional characters of food items are available world over and attracts the meat technologists and the food processors to bring some innovativeness in meat analog and its presentation and marketability so that the acceptability of meat analog can be overgrown by the consumers.

  16. Interactive NMR: A Simulation Based Teaching Tool for Fundamentals to Applications with Tangible Analogies

    Science.gov (United States)

    Griesse-Nascimento, Sarah; Bridger, Joshua; Brown, Keith; Westervelt, Robert

    2011-03-01

    Interactive computer simulations increase students' understanding of difficult concepts and their ability to explain complex ideas. We created a module of eight interactive programs and accompanying lesson plans for teaching the fundamental concepts of Nuclear Magnetic Resonance (NMR) and Magnetic Resonance Imaging (MRI) that we call interactive NMR (iNMR). We begin with an analogy between nuclear spins and metronomes to start to build intuition about the dynamics of spins in a magnetic field. We continue to explain T1, T2, and pulse sequences with the metronome analogy. The final three programs are used to introduce and explain the Magnetic Resonance Switch, a recent diagnostic technique based on NMR. A modern relevant application is useful to generate interest in the topic and confidence in the students' ability to apply their knowledge. The iNMR module was incorporated into a high school AP physics class. In a preliminary evaluation of implementation, students expressed enthusiasm and demonstrated enhanced understanding of the material relative to the previous year. Funded by NSF PHY-0646094 grant.

  17. Digital and analog communication systems

    Science.gov (United States)

    Shanmugam, K. S.

    1979-01-01

    The book presents an introductory treatment of digital and analog communication systems with emphasis on digital systems. Attention is given to the following topics: systems and signal analysis, random signal theory, information and channel capacity, baseband data transmission, analog signal transmission, noise in analog communication systems, digital carrier modulation schemes, error control coding, and the digital transmission of analog signals.

  18. Conceptual design of the TRACE detector readout using a compact, dead time-less analog memory ASIC

    OpenAIRE

    Aliaga Varea, Ramón José; Herrero Bosch, Vicente; Capra, S.; Pullia, A.; Dueñas, J. A.; Grassi, L.; Triossi, A.; Domingo Pardo, C.; Gadea Gironés, Rafael; González, V.; Hüyük, T.; Sanchís, E.; Gadea, A.; Mengoni, D.

    2015-01-01

    The new TRacking Array for light Charged particle Ejectiles (TRACE) detector system requires monitorization and sampling of all pulses in a large number of channels with very strict space and power consumption restrictions for the front-end electronics and cabling. Its readout system is to be based on analog memory ASICs with 64 channels each that sample a View the MathML source window of the waveform of any valid pulses at 200 MHz while discarding any other signals and are read out at 50 MHz...

  19. Semiconductor Quantum Electron Wave Transport, Diffraction, and Interference: Analysis, Device, and Measurement.

    Science.gov (United States)

    Henderson, Gregory Newell

    Semiconductor device dimensions are rapidly approaching a fundamental limit where drift-diffusion equations and the depletion approximation are no longer valid. In this regime, quantum effects can dominate device response. To increase further device density and speed, new devices must be designed that use these phenomena to positive advantage. In addition, quantum effects provide opportunities for a new class of devices which can perform functions previously unattainable with "conventional" semiconductor devices. This thesis has described research in the analysis of electron wave effects in semiconductors and the development of methods for the design, fabrication, and characterization of quantum devices based on these effects. First, an exact set of quantitative analogies are presented which allow the use of well understood optical design and analysis tools for the development of electron wave semiconductor devices. Motivated by these analogies, methods are presented for modeling electron wave grating diffraction using both an exact rigorous coupled-wave analysis and approximate analyses which are useful for grating design. Example electron wave grating switch and multiplexer designs are presented. In analogy to thin-film optics, the design and analysis of electron wave Fabry-Perot interference filters are also discussed. An innovative technique has been developed for testing these (and other) electron wave structures using Ballistic Electron Emission Microscopy (BEEM). This technique uses a liquid-helium temperature scanning tunneling microscope (STM) to perform spectroscopy of the electron transmittance as a function of electron energy. Experimental results show that BEEM can resolve even weak quantum effects, such as the reflectivity of a single interface between materials. Finally, methods are discussed for incorporating asymmetric electron wave Fabry-Perot filters into optoelectronic devices. Theoretical and experimental results show that such structures could

  20. High quality digital holographic reconstruction on analog film

    Science.gov (United States)

    Nelsen, B.; Hartmann, P.

    2017-05-01

    High quality real-time digital holographic reconstruction, i.e. at 30 Hz frame rates, has been at the forefront of research and has been hailed as the holy grail of display systems. While these efforts have produced a fascinating array of computer algorithms and technology, many applications of reconstructing high quality digital holograms do not require such high frame rates. In fact, applications such as 3D holographic lithography even require a stationary mask. Typical devices used for digital hologram reconstruction are based on spatial-light-modulator technology and this technology is great for reconstructing arbitrary holograms on the fly; however, it lacks the high spatial resolution achievable by its analog counterpart, holographic film. Analog holographic film is therefore the method of choice for reconstructing highquality static holograms. The challenge lies in taking a static, high-quality digitally calculated hologram and effectively writing it to holographic film. We have developed a theoretical system based on a tunable phase plate, an intensity adjustable high-coherence laser and a slip-stick based piezo rotation stage to effectively produce a digitally calculated hologram on analog film. The configuration reproduces the individual components, both the amplitude and phase, of the hologram in the Fourier domain. These Fourier components are then individually written on the holographic film after interfering with a reference beam. The system is analogous to writing angularly multiplexed plane waves with individual component phase control.

  1. Children's Development of Analogical Reasoning: Insights from Scene Analogy Problems

    Science.gov (United States)

    Richland, Lindsey E.; Morrison, Robert G.; Holyoak, Keith J.

    2006-01-01

    We explored how relational complexity and featural distraction, as varied in scene analogy problems, affect children's analogical reasoning performance. Results with 3- and 4-year-olds, 6- and 7-year-olds, 9- to 11-year-olds, and 13- and 14-year-olds indicate that when children can identify the critical structural relations in a scene analogy…

  2. CMOS Image Sensors: Electronic Camera On A Chip

    Science.gov (United States)

    Fossum, E. R.

    1995-01-01

    Recent advancements in CMOS image sensor technology are reviewed, including both passive pixel sensors and active pixel sensors. On- chip analog to digital converters and on-chip timing and control circuits permit realization of an electronic camera-on-a-chip. Highly miniaturized imaging systems based on CMOS image sensor technology are emerging as a competitor to charge-coupled devices for low cost uses.

  3. 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

  4. A PLL based automated magnetron tuning mechanism for electron accelerators

    International Nuclear Information System (INIS)

    Khan, A M; Mahfooz, Mohammed; Sanjeev, Ganesh

    2008-01-01

    In this paper we report on a control system developed to tune the magnetron frequency to get the maximum beam pulse in a Microtron (an electron accelerator facility at Mangalore University). The control system so designed consists of a Microcontroller Unit (MCU), a Phase Locked Loop (PLL) and a Digital to Analog Converter (DAC) to track and tune the magnetron frequency. A PLL is used to track the deviation of the magnetron output frequency, and by monitoring the reflected wave voltage level, the microcontroller unit tunes the magnetron with the help of a tuner mechanism connected through a stepper motor.

  5. A PLL based automated magnetron tuning mechanism for electron accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Khan, A M; Mahfooz, Mohammed [Dept. of Electronics, Mangalore University, Mangalagangotri, Karnataka State, India - 574 199 (India); Sanjeev, Ganesh [Microtron Centre, Mangalore University, Mangalagangotri, Karnataka State, India - 574 199 (India)], E-mail: mahfooz_81@yahoo.com

    2008-09-15

    In this paper we report on a control system developed to tune the magnetron frequency to get the maximum beam pulse in a Microtron (an electron accelerator facility at Mangalore University). The control system so designed consists of a Microcontroller Unit (MCU), a Phase Locked Loop (PLL) and a Digital to Analog Converter (DAC) to track and tune the magnetron frequency. A PLL is used to track the deviation of the magnetron output frequency, and by monitoring the reflected wave voltage level, the microcontroller unit tunes the magnetron with the help of a tuner mechanism connected through a stepper motor.

  6. Hydraulic Capacitor Analogy

    Science.gov (United States)

    Baser, Mustafa

    2007-01-01

    Students have difficulties in physics because of the abstract nature of concepts and principles. One of the effective methods for overcoming students' difficulties is the use of analogies to visualize abstract concepts to promote conceptual understanding. According to Iding, analogies are consistent with the tenets of constructivist learning…

  7. Epistemic Function and Ontology of Analog and Digital Images

    Directory of Open Access Journals (Sweden)

    Aleksandra Łukaszewicz Alcaraz

    2016-01-01

    Full Text Available The important epistemic function of photographic images is their active role in construction and reconstruction of our beliefs concerning the world and human identity, since we often consider photographs as presenting reality or even the Real itself. Because photography can convince people of how different social and ethnic groups and even they themselves look, documentary projects and the dissemination of photographic practices supported the transition from disciplinary society to the present-day society of control. While both analog and digital images are formed from the same basic materia, the ways in which this matter appears are distinctive. In the case of analog photography, we deal with physical and chemical matter, whereas with digital images we face electronic matter. Because digital photography allows endless modification of the image, we can no longer believe in the truthfulness of digital images.

  8. Demonstrations of analog-to-digital conversion using a frequency domain stretched processor.

    Science.gov (United States)

    Reibel, Randy Ray; Harrington, Calvin; Dahl, Jason; Ostrander, Charles; Roos, Peter Aaron; Berg, Trenton; Mohan, R Krishna; Neifeld, Mark A; Babbitt, Wm R

    2009-07-06

    The first proof-of-concept demonstrations are presented for a broadband photonic-assisted analog-to-digital converter (ADC) based on spatial spectral holography (SSH). The SSH-ADC acts as a frequency-domain stretch processor converting high bandwidth input signals to low bandwidth output signals, allowing the system to take advantage of high performance, low bandwidth electronic ADCs. Demonstrations with 50 MHz effective bandwidth are shown to highlight basic performance with approximately 5 effective bits of vertical resolution. Signal capture with 1600 MHz effective bandwidth is also shown. Because some SSH materials span over 100 GHz and have large time apertures (approximately 10 micros), this technique holds promise as a candidate for the next generation of ADCs.

  9. Study for material analogs of FeSb2: Material design for thermoelectric materials

    Science.gov (United States)

    Kang, Chang-Jong; Kotliar, Gabriel

    2018-03-01

    Using the ab initio evolutionary algorithm (implemented in uspex) and electronic structure calculations we investigate the properties of a new thermoelectric material FeSbAs, which is a material analog of the enigmatic thermoelectric FeSb2. We utilize the density functional theory and the Gutzwiller method to check the energetics. We find that FeSbAs can be made thermodynamically stable above ˜30 GPa. We investigate the electronic structure and thermoelectric properties of FeSbAs based on the density functional theory and compare with those of FeSb2. Above 50 K, FeSbAs has higher Seebeck coefficients than FeSb2. Upon doping, the figure of merit becomes larger for FeSbAs than for FeSb2. Another material analog FeSbP, was also investigated, and found thermodynamically unstable even at very high pressure. Regarding FeSb2 as a member of a family of compounds (FeSb2, FeSbAs, and FeSbP) we elucidate what are the chemical handles that control the gaps in this series. We also investigate solubility (As or P for Sb in FeSb2) we found As to be more soluble. Finally, we study a two-band model for thermoelectric properties and find that the temperature dependent chemical potential and the presence of the ionized impurities are important to explain the extremum in the Seebeck coefficient exhibited in experiments for FeSb2.

  10. Neuromorphic adaptive plastic scalable electronics: analog learning systems.

    Science.gov (United States)

    Srinivasa, Narayan; Cruz-Albrecht, Jose

    2012-01-01

    Decades of research to build programmable intelligent machines have demonstrated limited utility in complex, real-world environments. Comparing their performance with biological systems, these machines are less efficient by a factor of 1 million1 billion in complex, real-world environments. The Systems of Neuromorphic Adaptive Plastic Scalable Electronics (SyNAPSE) program is a multifaceted Defense Advanced Research Projects Agency (DARPA) project that seeks to break the programmable machine paradigm and define a new path for creating useful, intelligent machines. Since real-world systems exhibit infinite combinatorial complexity, electronic neuromorphic machine technology would be preferable in a host of applications, but useful and practical implementations still do not exist. HRL Laboratories LLC has embarked on addressing these challenges, and, in this article, we provide an overview of our project and progress made thus far.

  11. Production optimization of flying fish roe analogs using calcium alginate hydrogel beads

    Directory of Open Access Journals (Sweden)

    Bom-Bi Ha

    2016-09-01

    Full Text Available Abstract Due to decreased supplies of marine resources and byproducts, new processing technologies for the development of analogs for natural fishery products are becoming increasingly important in the fishing industry. In the present study, we investigated the optimal processing conditions for flying fish roe analogs based on alginate hydrogels. Optimized processing of these analogs was performed by response surface methodology. The optimal processing conditions for the flying fish roe analogs (based on sphericity were at a sodium alginate concentration of 2.41 %, calcium chloride solution curing time of 40.65 min, calcium chloride concentration of 1.51 %, and a reactor stir speed of 254×g. When the experiment was performed under these optimized conditions, the size (mm, sphericity (%, and rupture strength (kPa of the analogs were 2.2 ± 0.12, 98.2 ± 0.2, and 762 ± 24.68, respectively, indicating physical properties similar to their natural counterparts.

  12. Electronically-Scanned Pressure Sensors

    Science.gov (United States)

    Coe, C. F.; Parra, G. T.; Kauffman, R. C.

    1984-01-01

    Sensors not pneumatically switched. Electronic pressure-transducer scanning system constructed in modular form. Pressure transducer modules and analog to digital converter module small enough to fit within cavities of average-sized wind-tunnel models. All switching done electronically. Temperature controlled environment maintained within sensor modules so accuracy maintained while ambient temperature varies.

  13. Electronically Controlled Resistor Bank

    Science.gov (United States)

    Ross, Walter L.

    1987-01-01

    Resistance quickly varied in small steps over wide range. Device with no moving parts provides variable electrical resistance. Used with analog or digital circuity to provide electronic selection of large number of resistance values for testing, simulation, control, or other purposes. Nearest electromechanical equivalent of all-electronic device is potentiometer driven by servomotor.

  14. Terrestrial Spaceflight Analogs: Antarctica

    Science.gov (United States)

    Crucian, Brian

    2013-01-01

    Alterations in immune cell distribution and function, circadian misalignment, stress and latent viral reactivation appear to persist during Antarctic winterover at Concordia Station. Some of these changes are similar to those observed in Astronauts, either during or immediately following spaceflight. Others are unique to the Concordia analog. Based on some initial immune data and environmental conditions, Concordia winterover may be an appropriate analog for some flight-associated immune system changes and mission stress effects. An ongoing smaller control study at Neumayer III will address the influence of the hypoxic variable. Changes were observed in the peripheral blood leukocyte distribution consistent with immune mobilization, and similar to those observed during spaceflight. Alterations in cytokine production profiles were observed during winterover that are distinct from those observed during spaceflight, but potentially consistent with those observed during persistent hypobaric hypoxia. The reactivation of latent herpesviruses was observed during overwinter/isolation, that is consistently associated with dysregulation in immune function.

  15. Development of reconfigurable analog and digital circuits for plasma diagnostics measurement systems

    International Nuclear Information System (INIS)

    Srivastava, Amit Kumar; Sharma, Atish; Raval, Tushar

    2009-01-01

    In long pulse discharge tokamak, a large number of diagnostic channels are being used to understand the complex behavior of plasma. Different diagnostics demand different types of analog and digital processing for plasma parameters measurement. This leads to variable requirements of signal processing for diagnostic measurement. For such types of requirements, we have developed hardware with reconfigurable electronic devices, which provide flexible solution for rapid development of measurement system. Here the analog processing is achieved by Field Programmable Analog Array (FPAA) integrated circuit while reconfigurable digital devices (CPLD/FPGA) achieve digital processing. FPAA's provide an ideal integrated platform for implementing low to medium complexity analog signal processing. With dynamic reconfigurability, the functionality of the FPAA can be reconfigured in-system by the designer or on the fly by a microprocessor. This feature is quite useful to manipulate the tuning or the construction of any part of the analog circuit without interrupting operation of the FPAA, thus maintaining system integrity. The hardware operation control logic circuits are configured in the reconfigurable digital devices (CPLD/FPGA) to control proper hardware functioning. These reconfigurable devices provide the design flexibility and save the component space on the board. It also provides the flexibility for various setting through software. The circuit controlling commands are either issued by computer/processor or generated by circuit itself. (author)

  16. Developing a model for application of electronic banking based on electronic trust

    Directory of Open Access Journals (Sweden)

    Amir Hooshang Nazarpoori

    2014-05-01

    Full Text Available This study develops a model for application of electronic banking based on electronic trust among costumers of Day bank in KhoramAbad city. A sample of 150 people was selected based on stratified random sampling. Questionnaires were used for the investigation. Results indicate that technology-based factors, user-based factors, and trust had negative relationships with perceived risk types including financial, functional, personal, and private. Moreover, trust including trust in system and trust in bank had a positive relationship with tendency to use and real application of electronic banking.

  17. Application of natural analog studies to exploration for ore deposits

    International Nuclear Information System (INIS)

    Gustafson, D.L.

    1995-01-01

    Natural analogs are viewed as similarities in nature and are routinely utilized by exploration geologists in their search for economic mineral deposits. Ore deposit modeling is undertaken by geologists to direct their exploration activities toward favorable geologic environments and, therefore, successful programs. Two types of modeling are presented: (i) empirical model development based on the study of known ore deposit characteristics, and (ii) concept model development based on theoretical considerations and field observations that suggest a new deposit type, not known to exist in nature, may exist and justifies an exploration program. Key elements that are important in empirical model development are described, and examples of successful applications of these natural analogs to exploration are presented. A classical example of successful concept model development, the discovery of the McLaughlin gold mine in California, is presented. The utilization of natural analogs is an important facet of mineral exploration. Natural analogs guide explorationists in their search for new discoveries, increase the probability of success, and may decrease overall exploration expenditure

  18. Analogical Reasoning and Computer Programming.

    Science.gov (United States)

    Clement, Catherine A.; And Others

    1986-01-01

    A study of correlations between analogical reasoning and Logo programming mastery among female high school students related the results of pretests of analogical reasoning to posttests of programming mastery. A significant correlation was found between analogical reasoning and the ability to write subprocedures for use in several different…

  19. Analog circuit design automation for performance

    NARCIS (Netherlands)

    Ning, Zhen-Qiu; Ning, Zhen-Qiu; Kole, Marq; Kole, M.E.; Mouthaan, A.J.; Wallinga, Hans

    1992-01-01

    This paper describes an improved version of the program SEAS (a Simulated Evolution approach for Analog circuit Synthesis), in which an approach for selection of alternatives based on the evaluation of mutation values is developed, and design automafion for high performance comparators is covered.

  20. An analogy strategy for transformation optics

    International Nuclear Information System (INIS)

    Yao, Kan; Liu, Yongmin; Chen, Huanyang; Jiang, Xunya

    2014-01-01

    We introduce an analogy strategy to design transformation optical devices. Based on the similarities between field lines in different physical systems, the trajectories of light can be intuitively determined to curve in a gentle manner, and the resulting materials are isotropic and nonmagnetic. Furthermore, the physical meaning of the analogue problems plays a key role in the removal of dielectric singularities. We illustrate this approach by creating two designs of carpet cloak and a collimating lens as representative examples in two- and three-dimensional spaces, respectively. The analogy strategy not only reveals the intimate connections between different physical disciplines, such as optics, fluid mechanics and electrostatics, but also provides a heuristic pathway to designing advanced photonic systems

  1. Use of Nucleic Acid Analogs for the Study of Nucleic Acid Interactions

    Directory of Open Access Journals (Sweden)

    Shu-ichi Nakano

    2011-01-01

    Full Text Available Unnatural nucleosides have been explored to expand the properties and the applications of oligonucleotides. This paper briefly summarizes nucleic acid analogs in which the base is modified or replaced by an unnatural stacking group for the study of nucleic acid interactions. We also describe the nucleoside analogs of a base pair-mimic structure that we have examined. Although the base pair-mimic nucleosides possess a simplified stacking moiety of a phenyl or naphthyl group, they can be used as a structural analog of Watson-Crick base pairs. Remarkably, they can adopt two different conformations responding to their interaction energies, and one of them is the stacking conformation of the nonpolar aromatic group causing the site-selective flipping of the opposite base in a DNA double helix. The base pair-mimic nucleosides can be used to study the mechanism responsible for the base stacking and the flipping of bases out of a nucleic acid duplex.

  2. Flexible, fpga-based electronics for modular robots

    DEFF Research Database (Denmark)

    Brandt, David; Larsen, Jørgen Christian; Christensen, David Johan

    2008-01-01

    In this paper we introduce electronics for the ATRON self-reconfigurable robot based on field programmable gate arrays (FPGAs). The immediate advantage of using FPGAs is that some of the module’s electronics can be moved into the FPGA, thereby the number of components can be reduced. In the case...... the FPGA and therefore integrate task-specific electronics without physically changing the electronics or we can reconfigure the electronics for specific tasks. The disadvantages of an FPGA-based design include the cost of FPGAs, the extra layer of complexity in programming, and a limited increase in power...... consumption compared to micro-controllers. However, overall FPGAs make the electronics of modular robots more flexible and therefore may make them more suitable for real applications. AB - In this paper we introduce electronics for the ATRON self-reconfigurable robot based on field programmable gate arrays...

  3. Implementing and evaluating a fictitious electron dynamics method for the calculation of electronic structure: Application to the Si(100) surface

    International Nuclear Information System (INIS)

    Hoffman, M J H; Claassens, C H

    2006-01-01

    A density matrix based fictitious electron dynamics method for calculating electronic structure has been implemented within a semi-empirical quantum chemistry environment. This method uses an equation of motion that implicitly ensures the idempotency constraint on the density matrix. Test calculations showed that this method has potential of being combined with simultaneous atomic dynamics, in analogy to the popular Car-Parrinello method. In addition, the sparsity of the density matrix and the sophisticated though flexible way of ensuring idempotency conservation while integrating the equation of motion creates the potential of developing a fast linear scaling method

  4. MCD spectroscopy and TD-DFT calculations of low symmetry subnaphthalocyanine analogs.

    Science.gov (United States)

    Mack, John; Otaki, Tatsuya; Durfee, William S; Kobayashi, Nagao; Stillman, Martin J

    2014-07-01

    Magnetic circular dichroism (MCD) spectroscopy and time-dependent density functional theory (TD-DFT) calculations are used to analyze the electronic structure and optical properties of low-symmetry subnaphthalocyanine analogs with AAB and ABB structures formed during mixed condensations of tetrafluorophthalonitrile and 2,3-naphthalenedicarbonitrile. The results demonstrate that trends observed in the properties of phthalocyanine analogs can be used to fine tune the optical properties so that the Q(0,0) bands lie in the red region, in a manner that does not significantly destabilize the highest occupied molecular orbital (HOMO) energy relative to that of the parent subphthalocyanine ligand. Attempts to study the spectroscopy of anion radical species proved unsuccessful, since they proved to be unstable. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. New Synthetic Routes to Furocoumarins and Their Analogs: A Review

    Directory of Open Access Journals (Sweden)

    Valery F. Traven

    2004-02-01

    Full Text Available Many furocoumarins and their analogs possess a prominent photobiological activity. Some of them are successfully used as drugs in phototherapy of skin diseases. Fries rearrangement of acyloxyheteroarenes, condensation of acylhydroxyheteroarenes with α-carbonyl compounds under base catalysis and transformations of dihydrofurocoumarinones are new trends in synthesis of furocoumarins and their analogs.

  6. Analogical reasoning in children with specific language impairment: Evidence from a scene analogy task.

    Science.gov (United States)

    Krzemien, Magali; Jemel, Boutheina; Maillart, Christelle

    2017-01-01

    Analogical reasoning is a human ability that maps systems of relations. It develops along with relational knowledge, working memory and executive functions such as inhibition. It also maintains a mutual influence on language development. Some authors have taken a greater interest in the analogical reasoning ability of children with language disorders, specifically those with specific language impairment (SLI). These children apparently have weaker analogical reasoning abilities than their aged-matched peers without language disorders. Following cognitive theories of language acquisition, this deficit could be one of the causes of language disorders in SLI, especially those concerning productivity. To confirm this deficit and its link to language disorders, we use a scene analogy task to evaluate the analogical performance of SLI children and compare them to controls of the same age and linguistic abilities. Results show that children with SLI perform worse than age-matched peers, but similar to language-matched peers. They are more influenced by increased task difficulty. The association between language disorders and analogical reasoning in SLI can be confirmed. The hypothesis of limited processing capacity in SLI is also being considered.

  7. Passive Guaranteed Simulation of Analog Audio Circuits: A Port-Hamiltonian Approach

    Directory of Open Access Journals (Sweden)

    Antoine Falaize

    2016-09-01

    Full Text Available We present a method that generates passive-guaranteed stable simulations of analog audio circuits from electronic schematics for real-time issues. On one hand, this method is based on a continuous-time power-balanced state-space representation structured into its energy-storing parts, dissipative parts, and external sources. On the other hand, a numerical scheme is especially designed to preserve this structure and the power balance. These state-space structures define the class of port-Hamiltonian systems. The derivation of this structured system associated with the electronic circuit is achieved by an automated analysis of the interconnection network combined with a dictionary of models for each elementary component. The numerical scheme is based on the combination of finite differences applied on the state (with respect to the time variable and on the total energy (with respect to the state. This combination provides a discrete-time version of the power balance. This set of algorithms is valid for both the linear and nonlinear case. Finally, three applications of increasing complexities are given: a diode clipper, a common-emitter bipolar-junction transistor amplifier, and a wah pedal. The results are compared to offline simulations obtained from a popular circuit simulator.

  8. European Forest Cover During the Past 12,000 Years: A Palynological Reconstruction Based on Modern Analogs and Remote Sensing.

    Science.gov (United States)

    Zanon, Marco; Davis, Basil A S; Marquer, Laurent; Brewer, Simon; Kaplan, Jed O

    2018-01-01

    Characterization of land cover change in the past is fundamental to understand the evolution and present state of the Earth system, the amount of carbon and nutrient stocks in terrestrial ecosystems, and the role played by land-atmosphere interactions in influencing climate. The estimation of land cover changes using palynology is a mature field, as thousands of sites in Europe have been investigated over the last century. Nonetheless, a quantitative land cover reconstruction at a continental scale has been largely missing. Here, we present a series of maps detailing the evolution of European forest cover during last 12,000 years. Our reconstructions are based on the Modern Analog Technique (MAT): a calibration dataset is built by coupling modern pollen samples with the corresponding satellite-based forest-cover data. Fossil reconstructions are then performed by assigning to every fossil sample the average forest cover of its closest modern analogs. The occurrence of fossil pollen assemblages with no counterparts in modern vegetation represents a known limit of analog-based methods. To lessen the influence of no-analog situations, pollen taxa were converted into plant functional types prior to running the MAT algorithm. We then interpolate site-specific reconstructions for each timeslice using a four-dimensional gridding procedure to create continuous gridded maps at a continental scale. The performance of the MAT is compared against methodologically independent forest-cover reconstructions produced using the REVEALS method. MAT and REVEALS estimates are most of the time in good agreement at a trend level, yet MAT regularly underestimates the occurrence of densely forested situations, requiring the application of a bias correction procedure. The calibrated MAT-based maps draw a coherent picture of the establishment of forests in Europe in the Early Holocene with the greatest forest-cover fractions reconstructed between ∼8,500 and 6,000 calibrated years BP. This

  9. PEMETAAN ANALOGI PADA KONSEP ABSTRAK FISIKA

    Directory of Open Access Journals (Sweden)

    Nyoto Suseno

    2014-11-01

    Full Text Available The research of any where founded majority students have common difficulties in abstract physics concept. The result of observation, lecturers have problem  in teaching implementation of abstract concepts on physics learning. The objective of this research is to find out the ways how to overcome this problem. The research place of  physics education programs and senior high school. The data are colected by quetionere, observation and interview. The lecturer behavior to making out this case is use of analogy to make concrete a abstract concept. This action is true, because the analogies are dynamic tools that facilitate understanding, rather than representations of the correct and static explanations. Using analogies not only promoted profound understanding of abstract concept, but also helped students overcome their misconceptions. However used analogy in teaching not yet planed with seriousness, analogy used spontanously with the result that less optimal. By planing and selecting right analogy, the role of analogy can be achieved the optimal result. Therefore, it is important to maping analogies of abstract consepts on physics learning.

  10. Multilayered analog optical differentiating device: performance analysis on structural parameters.

    Science.gov (United States)

    Wu, Wenhui; Jiang, Wei; Yang, Jiang; Gong, Shaoxiang; Ma, Yungui

    2017-12-15

    Analogy optical devices (AODs) able to do mathematical computations have recently gained strong research interest for their potential applications as accelerating hardware in traditional electronic computers. The performance of these wavefront-processing devices is primarily decided by the accuracy of the angular spectral engineering. In this Letter, we show that the multilayer technique could be a promising method to flexibly design AODs according to the input wavefront conditions. As examples, various Si-SiO 2 -based multilayer films are designed that can precisely perform the second-order differentiation for the input wavefronts of different Fourier spectrum widths. The minimum number and thickness uncertainty of sublayers for the device performance are discussed. A technique by rescaling the Fourier spectrum intensity has been proposed in order to further improve the practical feasibility. These results are thought to be instrumental for the development of AODs.

  11. Science Teachers' Analogical Reasoning

    Science.gov (United States)

    Mozzer, Nilmara Braga; Justi, Rosária

    2013-01-01

    Analogies can play a relevant role in students' learning. However, for the effective use of analogies, teachers should not only have a well-prepared repertoire of validated analogies, which could serve as bridges between the students' prior knowledge and the scientific knowledge they desire them to understand, but also know how to…

  12. Oxindole based oxadiazole hybrid analogs: Novel α-glucosidase inhibitors.

    Science.gov (United States)

    Taha, Muhammad; Imran, Syahrul; Rahim, Fazal; Wadood, Abdul; Khan, Khalid Mohammed

    2018-02-01

    Inhibition of α-glucosidase is an effective strategy for controlling post-prandial hyperglycemia in diabetic patients. Beside these α-glucosidase inhibitors has been also used as anti-obesity and anti-viral drugs. Keeping in view the greater importance of α-glucosidase inhibitors here in this study we are presenting oxindole based oxadiazoles hybrid analogs (1-20) synthesis, characterized by different spectroscopic techniques including 1 H NMR and EI-MS and their α-glucosidase inhibitory activity. All compounds were found potent inhibitors for the enzyme with IC 50 values ranging between 1.25 ± 0.05 and 268.36 ± 4.22 µM when compared with the standard drug acarbose having IC 50 value 895.09 ± 2.04 µM. Our study identifies novel series of potent α-glucosidase inhibitors and further investigation on this may led to the lead compounds. A structure activity relationship has been established for all compounds. The interactions of the active compounds and enzyme active site were established with the help of molecular docking studies. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Session summary: Electronics, triggering and data acquisition

    International Nuclear Information System (INIS)

    Rescia, S.

    1991-12-01

    The session focused on the requirements for calorimetry at the SSC/LHC. Results on new readout techniques, calibration, radiation hard electronics and semiconductor devices, analog and digital front and electronics, and trigger strategies are presented

  14. All-optical analog-to-digital converter based on Kerr effect in photonic crystal

    Science.gov (United States)

    Jafari, Dariush; Nurmohammadi, Tofiq; Asadi, Mohammad Javad; Abbasian, Karim

    2018-05-01

    In this paper, a novel all-optical analog-to-digital converter (AOADC) is proposed and simulated for proof of principle. This AOADC is designed to operate in the range of telecom wavelength (1550 nm). A cavity made of nonlinear Kerr material in photonic crystal (PhC), is designed to achieve an optical analog-to-digital conversion with 1 Tera sample per second (TS/s) and the total footprint of 42 μm2 . The simulation is done using finite-difference time domain (FDTD) method.

  15. Dynamic mesh optimization based on the spring analogy

    Directory of Open Access Journals (Sweden)

    Schmidt Jonas

    2014-01-01

    Full Text Available We present an implementation of the spring analogy for three dimensional meshes in OpenFOAM. All parameters of the spring system are treated as fields that can either be pre-defined by the user, or updated at each time step according to specified geometrical regions or diffusion equations. The purpose of the method is to provide a pre-processing tool for mesh optimization. We study three simple test cases, a deformed block, an airfoil and a hill, and we analyze the evolution of skewness, non-orthogonality and aspect ratio during the approach of dynamic equilibrium.

  16. A flexible analog memory address list manager for PHENIX

    International Nuclear Information System (INIS)

    Ericson, M.N.; Musrock, M.S.; Britton, C.L. Jr.; Walker, J.W.; Wintenberg, A.L.; Young, G.R.; Allen, M.D.

    1996-01-01

    A programmable analog memory address list manager has been developed for use with all analog memory-based detector subsystems of PHENIX. The unit provides simultaneous read/write control, cell write-over protection for both a Level-1 trigger decision delay and digitization latency, and re-ordering of AMU addresses following conversion, at a beam crossing rate of 105 ns. Addresses are handled such that up to 5 Level-1 (LVL-1) events can be maintained in the AMU without write-over. Data tagging is implemented for handling overlapping and shared beam-event data packets. Full usage in all PHENIX analog memory-based detector subsystems is accomplished by the use of detector-specific programmable parameters--the number of data samples per valid LVL-1 trigger and the sample spacing. Architectural candidates for the system are discussed with emphasis on implementation implications. Details of the design are presented including application specifics, timing information, and test results from a full implementation using field programmable gate arrays (FPGAs)

  17. 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.

  18. The analog computation and contrast test of leaked electromagnetic noise in the klystron corridor

    International Nuclear Information System (INIS)

    Tao Xiaoping; Wang Guicheng

    2001-01-01

    In order to obtain a better understand of the characteristics and location of noise source, the leaked electromagnetic noise in the klystron corridor of NSRL has been analogously calculated. The computational method and formula of high frequency leaked noise of the modulator were given. On-the-spot contrast tests have been made on the base of analog computation. The contrast test results show reasonableness of analog computation and whereby offer a theoretic base for reducing noise leakage in corridor

  19. Reasoning by analogy requires the left frontal pole: lesion-deficit mapping and clinical implications.

    Science.gov (United States)

    Urbanski, Marika; Bréchemier, Marie-Laure; Garcin, Béatrice; Bendetowicz, David; Thiebaut de Schotten, Michel; Foulon, Chris; Rosso, Charlotte; Clarençon, Frédéric; Dupont, Sophie; Pradat-Diehl, Pascale; Labeyrie, Marc-Antoine; Levy, Richard; Volle, Emmanuelle

    2016-06-01

    SEE BURGESS DOI101093/BRAIN/AWW092 FOR A SCIENTIFIC COMMENTARY ON THIS ARTICLE  : Analogical reasoning is at the core of the generalization and abstraction processes that enable concept formation and creativity. The impact of neurological diseases on analogical reasoning is poorly known, despite its importance in everyday life and in society. Neuroimaging studies of healthy subjects and the few studies that have been performed on patients have highlighted the importance of the prefrontal cortex in analogical reasoning. However, the critical cerebral bases for analogical reasoning deficits remain elusive. In the current study, we examined analogical reasoning abilities in 27 patients with focal damage in the frontal lobes and performed voxel-based lesion-behaviour mapping and tractography analyses to investigate the structures critical for analogical reasoning. The findings revealed that damage to the left rostrolateral prefrontal region (or some of its long-range connections) specifically impaired the ability to reason by analogies. A short version of the analogy task predicted the existence of a left rostrolateral prefrontal lesion with good accuracy. Experimental manipulations of the analogy tasks suggested that this region plays a role in relational matching or integration. The current lesion approach demonstrated that the left rostrolateral prefrontal region is a critical node in the analogy network. Our results also suggested that analogy tasks should be translated to clinical practice to refine the neuropsychological assessment of patients with frontal lobe lesions. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. A Low Noise CMOS Readout Based on a Polymer-Coated SAW Array for Miniature Electronic Nose

    Directory of Open Access Journals (Sweden)

    Cheng-Chun Wu

    2016-10-01

    Full Text Available An electronic nose (E-Nose is one of the applications for surface acoustic wave (SAW sensors. In this paper, we present a low-noise complementary metal–oxide–semiconductor (CMOS readout application-specific integrated circuit (ASIC based on an SAW sensor array for achieving a miniature E-Nose. The center frequency of the SAW sensors was measured to be approximately 114 MHz. Because of interference between the sensors, we designed a low-noise CMOS frequency readout circuit to enable the SAW sensor to obtain frequency variation. The proposed circuit was fabricated in Taiwan Semiconductor Manufacturing Company (TSMC 0.18 μm 1P6M CMOS process technology. The total chip size was nearly 1203 × 1203 μm2. The chip was operated at a supply voltage of 1 V for a digital circuit and 1.8 V for an analog circuit. The least measurable difference between frequencies was 4 Hz. The detection limit of the system, when estimated using methanol and ethanol, was 0.1 ppm. Their linearity was in the range of 0.1 to 26,000 ppm. The power consumption levels of the analog and digital circuits were 1.742 mW and 761 μW, respectively.

  1. Digital redesign of anti-wind-up controller for cascaded analog system.

    Science.gov (United States)

    Chen, Y S; Tsai, J S H; Shieh, L S; Moussighi, M M

    2003-01-01

    The cascaded conventional anti-wind-up (CAW) design method for integral controller is discussed. Then, the prediction-based digital redesign methodology is utilized to find the new pulse amplitude modulated (PAM) digital controller for effective digital control of the analog plant with input saturation constraint. The desired digital controller is determined from existing or pre-designed CAW analog controller. The proposed method provides a novel methodology for indirect digital design of a continuous-time unity output-feedback system with a cascaded analog controller as in the case of PID controllers for industrial control processes with the presence of actuator saturations. It enables us to implement an existing or pre-designed cascaded CAW analog controller via a digital controller effectively.

  2. Absolute Negative Resistance Induced by Directional Electron-Electron Scattering in a Two-Dimensional Electron Gas

    Science.gov (United States)

    Kaya, Ismet I.; Eberl, Karl

    2007-05-01

    A three-terminal device formed by two electrostatic barriers crossing an asymmetrically patterned two-dimensional electron gas displays an unusual potential depression at the middle contact, yielding absolute negative resistance. The device displays momentum and current transfer ratios that far exceed unity. The observed reversal of the current or potential in the middle terminal can be interpreted as the analog of Bernoulli’s effect in a Fermi liquid. The results are explained by directional scattering of electrons in two dimensions.

  3. Digital signal processing in power electronics control circuits

    CERN Document Server

    Sozanski, Krzysztof

    2013-01-01

    Many digital control circuits in current literature are described using analog transmittance. This may not always be acceptable, especially if the sampling frequency and power transistor switching frequencies are close to the band of interest. Therefore, a digital circuit is considered as a digital controller rather than an analog circuit. This helps to avoid errors and instability in high frequency components. Digital Signal Processing in Power Electronics Control Circuits covers problems concerning the design and realization of digital control algorithms for power electronics circuits using

  4. A standardized way to select, evaluate, and test an analog-to-digital converter for ultrawide bandwidth radiofrequency signals based on user's needs, ideal, published,and actual specifications

    Science.gov (United States)

    Chang, Daniel Y.; Rowe, Neil C.

    2012-06-01

    The most important adverse impact on the Electronic Warfare (EW) simulation is that the number of signal sources that can be tested simultaneously is relatively small. When the number of signal sources increases, the analog hardware, complexity and costs grow by the order of N2, since the number of connections among N components is O(N*N) and the signal communication is bi-directional. To solve this problem, digitization of the signal is suggested. In digitizing a radiofrequency signal, an Analog-to-Digital Converter (ADC) is widely used. Most research studies on ADCs are conducted from designer/test engineers' perspective. Some research studies are conducted from market's perspective. This paper presents a generic way to select, evaluate and test ultra high bandwidth COTS ADCs and generate requirements for digitizing continuous time signals from the perspective of user's needs. Based on user's needs, as well as vendor's published, ideal and actual specifications, a decision can be made in selecting a proper ADC for an application. To support our arguments and illustrate the methodology, we evaluate a Tektronix TADC-1000, an 8-bit and 12 gigasamples per second ADC. This project is funded by JEWEL lab, NAWCWD at Point Mugu, CA.

  5. Students' Pre- and Post-Teaching Analogical Reasoning when They Draw Their Analogies

    Science.gov (United States)

    Mozzer, Nilmara Braga; Justi, Rosaria

    2012-01-01

    Analogies are parts of human thought. From them, we can acquire new knowledge or change that which already exists in our cognitive structure. In this sense, understanding the analogical reasoning process becomes an essential condition to understand how we learn. Despite the importance of such an understanding, there is no general agreement in…

  6. A self-testing method of large analog circuits in electronic embedded systems

    Energy Technology Data Exchange (ETDEWEB)

    Czaja, Z, E-mail: zbczaja@pg.gda.p [Gdansk University of Technology, Faculty of Electronics, Telecommunications and Informatics, Department of Optoelectronics and Electronic Systems, ul. G. Narutowicza 11/12, 80-233 Gdansk (Poland)

    2010-07-01

    A new self-testing method of high-order filters consisting of a chain of first- or second-order filter units of mixed-signal electronic embedded systems controlled by microcontrollers or DSPs is presented in the paper. The main idea of the method bases on the fact that the signal response of the given filter unit is treated as the signal stimulation of the next filter unit. Thanks to this, a simple reconfigurable BIST consisting of only internal devices of the microcontroller controlling the system was obtained.

  7. A self-testing method of large analog circuits in electronic embedded systems

    International Nuclear Information System (INIS)

    Czaja, Z

    2010-01-01

    A new self-testing method of high-order filters consisting of a chain of first- or second-order filter units of mixed-signal electronic embedded systems controlled by microcontrollers or DSPs is presented in the paper. The main idea of the method bases on the fact that the signal response of the given filter unit is treated as the signal stimulation of the next filter unit. Thanks to this, a simple reconfigurable BIST consisting of only internal devices of the microcontroller controlling the system was obtained.

  8. A 13-Bits wilkinson analog-digital converter for NIM acquisition system

    International Nuclear Information System (INIS)

    Acosta Toledo, R.; Osorio Deliz, J.; Arista Romeu, E.; Fernandez, J.

    1994-01-01

    A new 13-bits Wilkinson analog-digital converter is described. The aim of this work is to describe the circuits of sample and hold, memory condensator loading and releasing PROM based control memory logic, zero level detection and correction. The converter is designed for the digital measurement of the peak amplitudes of pulses with statistical or periodical time distribution. The analog-digital converter may be used in spectrometric systems, multi-channel analysers or any similar PC based system

  9. Conjecturing via analogical reasoning constructs ordinary students into like gifted student

    Science.gov (United States)

    Supratman; Ratnaningsih, N.; Ryane, S.

    2017-12-01

    The purpose of this study is to reveal the development of knowledge of ordinary students to be like gifted students in the classroom based on Piaget's theory. In exposing it, students are given an open problem of classical analogy. Researchers explore students who conjecture via analogical reasoning in problem solving. Of the 32 students, through the method of think out loud and the interview was completed: 25 students conjecture via analogical reasoning. Of the 25 students, all of them have almost the same character in problem solving/knowledge construction. For that, a student is taken to analyze the thinking process while solving the problem/construction of knowledge based on Piaget's theory. Based on Piaget's theory in the development of the same knowledge, gifted students and ordinary students have similar structures in final equilibrium. They begin processing: assimilation and accommodation of problem, strategies, and relationships.

  10. Icelandic basaltic geothermal field: A natural analog for nuclear waste isolation in basalt

    International Nuclear Information System (INIS)

    Ulmer, G.C.; Grandstaff, D.E.

    1984-01-01

    Analog studies of Icelandic geothermal fields have shown that the design of nuclear waste repositories in basalt can benefit by comparison to the data base already available from the development of these geothermal fields. A high degree of similarity exists between these two systems: their petrology, groundwater geochemistry, mineral solubilities, hydrologic parameters, temperature ranges, water-rock redox equilibria, hydrothermal pH values, and secondary mineralogies all show considerable overlap in the range of values. The experimentally-simulated hydrothermal studies of the basaltic nuclear waste repository rocks have, at this time, produced a data base that receives a strong confirmation from the Icelandic analog. Furthermore, the Icelandic analog should eventually be employed to extrapolate into higher and lower temperatures, into longer time-base chemical comparisons, and into more realistic mineral deposition studies, than have been possible in the laboratory evaluations of the nuclear waste repository designs. This eventual use of the Icelandic analog will require cooperative work with the Icelandic Geological Survey. 46 refs., 4 figs., 2 tabs

  11. Fermion analogy for layered superconducting films in parallel magnetic field

    International Nuclear Information System (INIS)

    Rodriguez, J.P.

    1997-01-01

    The equivalence between the Lawrence-Doniach model for films of extreme type-II layered superconductors and a generalization of the back-scattering model for spin-(1/2) electrons in one dimension is demonstrated. This fermion analogy is then exploited to obtain an anomalous H parallel -1 tail for the parallel equilibrium magnetization of the minimal double-layer case in the limit of high parallel magnetic fields H parallel for temperatures in the critical regime. (orig.)

  12. ANUSANSKAR: a 16 channel frontend electronics (FEE) ASIC targeted for silicon pixel array detector based prototype Alice FOCAL

    International Nuclear Information System (INIS)

    Mukhopadhyay, Sourav; Chandratre, V.B.; Sukhwani, Menka; Pithawa, C.K.; Singaraju, Ramnarayan; Muhuri, Sanjib; Nayak, T.; Khan, S.A.; Saini, Jogendra

    2013-01-01

    ANUSANSKAR is a 16 channel pulse processing ASIC with analog multiplexed output designed in 0.7 um standard CMOS technology with each channel consisting of CSA, Semi Gaussian pulse shaper, DC cancellation and pedestal control, track and hold, output buffer blocks. The ASIC's analog multiplexed output can be read serially in daisy-chain topology. Testing, characterization and validation of ANUSANSKAR ASIC as readout for prototype ALICE forward calorimeter (FOCAL) has been carried out in PS beam line at CERN with up to 6 GeV of pion and electron beam. This paper describes the ANUSANSKAR ASIC along with the experimental results. (author)

  13. The CMS Fast Beams Condition Monitor Backend Electronics based on MicroTCA technology

    CERN Document Server

    Zagozdzinska, Agnieszka Anna

    2016-01-01

    The Fast Beams Condition Monitor (BCM1F), upgraded for LHC Run II, is one sub-system of the Beam Radiation Instrumentation and Luminosity Project of the CMS experiment. It is based on 24 single crystal CVD diamond sensors. Each sensor is metallised with two pads, being read out by a dedicated fast frontend chip produced in 130 nm CMOS technology. Signals for real time monitoring are processed by custom-made back-end electronics to measure separately rates corresponding to LHC collision products, machine induced background and residual activation exploiting different arrival times. The system is built in MicroTCA technology and uses high speed analog-to-digital converters. The data processing module designed for the FPGA allows a distinguishing of collision and machine induced background, both synchronous to the LHC clock, from the residual activation products. In operational modes of high rates, consecutive events, spaced in time by less than 12.5 ns, may partially overlap. Hence, novel signal processing tec...

  14. Demonstrations for scanning probe microscopy based on a macroscopic analogy

    Czech Academy of Sciences Publication Activity Database

    Hajková, Z.; Fejfar, Antonín; Smejkal, P.

    2013-01-01

    Roč. 90, č. 3 (2013), s. 361-363 ISSN 0021-9584 R&D Projects: GA MŠk(CZ) LM2011026 Institutional support: RVO:68378271 Keywords : high school /introductory chemistry * first-year undergraduate/genera * demonstrations * interdisciplinary/multidisciplinary * analogies/transfer * atomic Subject RIV: AM - Education Impact factor: 1.001, year: 2013 http://pubs.acs.org/doi/abs/10.1021/ed3004947

  15. Analog circuit design art, science and personalities

    CERN Document Server

    Williams, Jim

    1991-01-01

    This book is far more than just another tutorial or reference guide - it's a tour through the world of analog design, combining theory and applications with the philosophies behind the design process. Readers will learn how leading analog circuit designers approach problems and how they think about solutions to those problems. They'll also learn about the `analog way' - a broad, flexible method of thinking about analog design tasks.A comprehensive and useful guide to analog theory and applications. Covers visualizing the operation of analog circuits. Looks at how to rap

  16. Simulation of Rossi-α method with analog Monte-Carlo method

    International Nuclear Information System (INIS)

    Lu Yuzhao; Xie Qilin; Song Lingli; Liu Hangang

    2012-01-01

    The analog Monte-Carlo code for simulating Rossi-α method based on Geant4 was developed. The prompt neutron decay constant α of six metal uranium configurations in Oak Ridge National Laboratory were calculated. α was also calculated by Burst-Neutron method and the result was consistent with the result of Rossi-α method. There is the difference between results of analog Monte-Carlo simulation and experiment, and the reasons for the difference is the gaps between uranium layers. The influence of gaps decrease as the sub-criticality deepens. The relative difference between results of analog Monte-Carlo simulation and experiment changes from 19% to 0.19%. (authors)

  17. A Demonstrator Analog Signal Processing Circuit in a Radiation Hard SOI-CMOS Technology

    CERN Multimedia

    2002-01-01

    % RD-9 A Demonstrator Analog Signal Processing Circuit in a Radiation Hard SOI-CMOS Technology \\\\ \\\\Radiation hardened SOI-CMOS (Silicon-On-Insulator, Complementary Metal-Oxide- \\linebreak Semiconductor planar microelectronic circuit technology) was a likely candidate technology for mixed analog-digital signal processing electronics in experiments at the future high luminosity hadron colliders. We have studied the analog characteristics of circuit designs realized in the Thomson TCS radiation hard technologies HSOI3-HD. The feature size of this technology was 1.2 $\\mu$m. We have irradiated several devices up to 25~Mrad and 3.10$^{14}$ neutrons cm$^{-2}$. Gain, noise characteristics and speed have been measured. Irradiation introduces a degradation which in the interesting bandwidth of 0.01~MHz~-~1~MHz is less than 40\\%. \\\\ \\\\Some specific SOI phenomena have been studied in detail, like the influence on the noise spectrum of series resistence in the thin silicon film that constitutes the body of the transistor...

  18. Resistive RAMs as analog trimming elements

    Science.gov (United States)

    Aziza, H.; Perez, A.; Portal, J. M.

    2018-04-01

    This work investigates the use of Resistive Random Access Memory (RRAM) as an analog trimming device. The analog storage feature of the RRAM cell is evaluated and the ability of the RRAM to hold several resistance states is exploited to propose analog trim elements. To modulate the memory cell resistance, a series of short programming pulses are applied across the RRAM cell allowing a fine calibration of the RRAM resistance. The RRAM non volatility feature makes the analog device powers up already calibrated for the system in which the analog trimmed structure is embedded. To validate the concept, a test structure consisting of a voltage reference is evaluated.

  19. Electrostatic analogy for symmetron gravity

    Science.gov (United States)

    Ogden, Lillie; Brown, Katherine; Mathur, Harsh; Rovelli, Kevin

    2017-12-01

    The symmetron model is a scalar-tensor theory of gravity with a screening mechanism that suppresses the effect of the symmetron field at high densities characteristic of the Solar System and laboratory scales but allows it to act with gravitational strength at low density on the cosmological scale. We elucidate the screening mechanism by showing that in the quasistatic Newtonian limit there are precise analogies between symmetron gravity and electrostatics for both strong and weak screening. For strong screening we find that large dense bodies behave in a manner analogous to perfect conductors in electrostatics. Based on this analogy we find that the symmetron field exhibits a lightning rod effect wherein the field gradients are enhanced near the ends of pointed or elongated objects. An ellipsoid placed in a uniform symmetron gradient is shown to experience a torque. By symmetry there is no gravitational torque in this case. Hence this effect unmasks the symmetron and might serve as the basis for future laboratory experiments. The symmetron force between a point mass and a large dense body includes a component corresponding to the interaction of the point mass with its image in the larger body. None of these effects have counterparts in the Newtonian limit of Einstein gravity. We discuss the similarities between symmetron gravity and the chameleon model as well as the differences between the two.

  20. 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)

  1. Analog and digital dividers for mass spectrometers

    International Nuclear Information System (INIS)

    Osipov, A.K.

    1980-01-01

    Errors of four different types of stress dividers used in statical mass-spectrometers for determination of mass number by accelerating stress are analyzed. The simplest flowsheet of the analog divider comprises operation amplifier, in the chain of the negative feedback of which a multiplication device on differential cascade is switched- in. This analog divider has high sensitivity to temperature and high error approximately 5%. Application of the multiplier on differential cascade with normalization permits to increase temperature stability and decrease the error up to 1%. Another type of the analog divider is a logarithmic divider the error of which is constant within the whole operation range and it constitutes 1-5%. The digital divider with a digital-analog transformer (DAT) has the error of +-0.015% which is determined by the error of detectors and resistance of keys in the locked state. Considered is the design of a divider based on transformation of the inlet stress into the time period. The error of the divider is determined in this case mainly by stress of the zero shift of the operation amplifier (it should be compensated) and relative threshold stability of the comparator triggering which equals (2-3)x10 -4 . It is noted that the divider with DAT application and the divider with the use of stress transformation within the time period are most perspective ones for statical mass-spectrometers [ru

  2. Introduction to electronics and applications in high energy physics

    CERN Multimedia

    CERN. Geneva

    2004-01-01

    Electronics in HEP experiments: specificities and evolution The Art of Electronics: is there something beyond Ohm's law? Basic building blocks of Analog electronics: quickly understanding a schematic Charge preamps, current preamps and future preamps, shaping and the rest Electronics noise: fundamental and practical Evolution of technology: ASICs, FPGAs...

  3. A dark business, full of shadows: analogy and theology in William Harvey.

    Science.gov (United States)

    Goldberg, Benjamin

    2013-09-01

    In a short work called De conceptione appended to the end of his Exercitationes de generatione animalium (1651), William Harvey developed a rather strange analogy. To explain how such marvelous productions as living beings were generated from the rather inauspicious ingredients of animal reproduction, Harvey argued that conception in the womb was like conception in the brain. It was mostly rejected at the time; it now seems a ludicrous theory based upon homonymy. However, this analogy offers insight into the structure and function of analogies in early modern natural philosophy. In this essay I hope to not only describe the complex nature of Harvey's analogy, but also offer a novel interpretation of his use of analogical reasoning, substantially revising the account offered by Guido Giglioni (1993). I discuss two points of conceptual change and negotiation in connection with Harvey's analogy, understanding it as both a confrontation between the border of the natural and the supernatural, as well as a moment in the history of psychology. My interpretation touches upon a number of important aspects, including why the analogy was rejected, how Harvey systematically deployed analogies according to his notions of natural philosophical method, how the analogy fits into contemporary discussions of analogies in science, and finally, how the analogy must be seen in the context of changing Renaissance notions of the science of the soul, ultimately confronting the problem of how to understand final causality in Aristotelian science. In connection with the last, I conclude the essay by turning to how Harvey embeds the analogy within a natural theological cosmology. Copyright © 2013. Published by Elsevier Ltd.

  4. Power electronics and motor drives

    CERN Document Server

    Wilamowski, Bogdan M

    2011-01-01

    Universities throughout the world typically provide an excellent education in the various aspects of electronics, however their focus is normally on traditional low power electronics. In contrast, in the industrial environment, there is a need for high power electronics that is used to control electromechanical systems in addition to the low power electronics typically employed for analog and digital systems. To address this need, Section 1 of this volume in The Industrial Electronics Handbook, Second Edition, is focused on special high power semiconductor devices. Section 2 not only describes

  5. Moisture ingress into electronics enclosures under isothermal conditions

    International Nuclear Information System (INIS)

    Staliulionis, Ž.; Jabbari, M.; Hattel, J. H.

    2016-01-01

    The number of electronics used in outdoor environment is constantly growing. The humidity causes about 19 % of all electronics failures and, especially, moisture increases these problems due to the ongoing process of miniaturization and lower power consumption of electronic components. Moisture loads are still not understood well by design engineers, therefore this field has become one of the bottlenecks in the electronics system design. The objective of this paper is to model moisture ingress into an electronics enclosure under isothermal conditions. The moisture diffusion model is based on a 1D quasi-steady state (QSS) approximation for Fick’s second law. This QSS approach is also described with an electrical analogy which gives a fast tool in modelling of the moisture response. The same QSS method is applied to ambient water vapour variations. The obtained results are compared to an analytical solution and very good agreement is found.

  6. Challenges in Using Analogies

    Science.gov (United States)

    Lin, Shih-Yin; Singh, Chandralekha

    2011-01-01

    Learning physics requires understanding the applicability of fundamental principles in a variety of contexts that share deep features. One way to help students learn physics is via analogical reasoning. Students can be taught to make an analogy between situations that are more familiar or easier to understand and another situation where the same…

  7. Aida-CMK multi-algorithm optimization kernel applied to analog IC sizing

    CERN Document Server

    Lourenço, Ricardo; Horta, Nuno

    2015-01-01

    This work addresses the research and development of an innovative optimization kernel applied to analog integrated circuit (IC) design. Particularly, this works describes the modifications inside the AIDA Framework, an electronic design automation framework fully developed by at the Integrated Circuits Group-LX of the Instituto de Telecomunicações, Lisbon. It focusses on AIDA-CMK, by enhancing AIDA-C, which is the circuit optimizer component of AIDA, with a new multi-objective multi-constraint optimization module that constructs a base for multiple algorithm implementations. The proposed solution implements three approaches to multi-objective multi-constraint optimization, namely, an evolutionary approach with NSGAII, a swarm intelligence approach with MOPSO and stochastic hill climbing approach with MOSA. Moreover, the implemented structure allows the easy hybridization between kernels transforming the previous simple NSGAII optimization module into a more evolved and versatile module supporting multiple s...

  8. Sensing Methods for Detecting Analog Television Signals

    Science.gov (United States)

    Rahman, Mohammad Azizur; Song, Chunyi; Harada, Hiroshi

    This paper introduces a unified method of spectrum sensing for all existing analog television (TV) signals including NTSC, PAL and SECAM. We propose a correlation based method (CBM) with a single reference signal for sensing any analog TV signals. In addition we also propose an improved energy detection method. The CBM approach has been implemented in a hardware prototype specially designed for participating in Singapore TV white space (WS) test trial conducted by Infocomm Development Authority (IDA) of the Singapore government. Analytical and simulation results of the CBM method will be presented in the paper, as well as hardware testing results for sensing various analog TV signals. Both AWGN and fading channels will be considered. It is shown that the theoretical results closely match with those from simulations. Sensing performance of the hardware prototype will also be presented in fading environment by using a fading simulator. We present performance of the proposed techniques in terms of probability of false alarm, probability of detection, sensing time etc. We also present a comparative study of the various techniques.

  9. Analogical processes in children's understanding of spatial representations.

    Science.gov (United States)

    Yuan, Lei; Uttal, David; Gentner, Dedre

    2017-06-01

    We propose that map reading can be construed as a form of analogical mapping. We tested 2 predictions that follow from this claim: First, young children's patterns of performance in map reading tasks should parallel those found in analogical mapping tasks; and, second, children will benefit from guided alignment instructions that help them see the relational correspondences between the map and the space. In 4 experiments, 3-year-olds completed a map reading task in which they were asked to find hidden objects in a miniature room, using a corresponding map. We manipulated the availability of guided alignment (showing children the analogical mapping between maps and spaces; Experiments 1, 2, and 3a), the format of guided alignment (gesture or relational language; Experiment 2), and the iconicity of maps (Experiments 3a and 3b). We found that (a) young children's difficulties in map reading follow from known patterns of analogical development-for example, focusing on object similarity over relational similarity; and (b) guided alignment based on analogical reasoning led to substantially better performance. Results also indicated that children's map reading performance was affected by the format of guided alignment, the iconicity of the maps, and the order of tasks. The results bear on the developmental mechanisms underlying young children's learning of spatial representations and also suggest ways to support this learning. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  10. The Micro-Category Account of Analogy

    Science.gov (United States)

    Green, Adam E.; Fugelsang, Jonathan A.; Kraemer, David J. M.; Dunbar, Kevin N.

    2008-01-01

    Here, we investigate how activation of mental representations of categories during analogical reasoning influences subsequent cognitive processing. Specifically, we present and test the central predictions of the "Micro-Category" account of analogy. This account emphasizes the role of categories in aligning terms for analogical mapping. In a…

  11. An emergent approach to analogical inference

    Science.gov (United States)

    Thibodeau, Paul H.; Flusberg, Stephen J.; Glick, Jeremy J.; Sternberg, Daniel A.

    2013-03-01

    In recent years, a growing number of researchers have proposed that analogy is a core component of human cognition. According to the dominant theoretical viewpoint, analogical reasoning requires a specific suite of cognitive machinery, including explicitly coded symbolic representations and a mapping or binding mechanism that operates over these representations. Here we offer an alternative approach: we find that analogical inference can emerge naturally and spontaneously from a relatively simple, error-driven learning mechanism without the need to posit any additional analogy-specific machinery. The results also parallel findings from the developmental literature on analogy, demonstrating a shift from an initial reliance on surface feature similarity to the use of relational similarity later in training. Variants of the model allow us to consider and rule out alternative accounts of its performance. We conclude by discussing how these findings can potentially refine our understanding of the processes that are required to perform analogical inference.

  12. Children's analogical reasoning about natural phenomena.

    Science.gov (United States)

    Pauen, S; Wilkening, F

    1997-10-01

    This report investigates children's analogical reasoning in a physics task, using an analogy generated by the children rather than by the experimenter. A total of 127 elementary school children took part in three related studies. Children learned to predict the behavior of a balance scale. Later, they were asked to solve a force interaction problem. Two versions of the balance scale training were devised: version A suggested an incorrect solution to the target problem (negative analogy), and version B suggested a correct solution to the target problem (positive analogy). In Study 1, 9- to 10-year-olds showed spontaneous transfer in both training conditions. In Study 2, 7-year-olds did not show any transfer in the positive analogy condition. Study 3 revealed that the lack of transfer in younger children was not due to a failure either to notice the analogy or to perform the mapping. Instead, 7-year-olds transferred only selected aspects of the correct solution. Copyright 1997 Academic Press.

  13. Working memory predicts children's analogical reasoning.

    Science.gov (United States)

    Simms, Nina K; Frausel, Rebecca R; Richland, Lindsey E

    2018-02-01

    Analogical reasoning is the cognitive skill of drawing relationships between representations, often between prior knowledge and new representations, that allows for bootstrapping cognitive and language development. Analogical reasoning proficiency develops substantially during childhood, although the mechanisms underlying this development have been debated, with developing cognitive resources as one proposed mechanism. We explored the role of executive function (EF) in supporting children's analogical reasoning development, with the goal of determining whether predicted aspects of EF were related to analogical development at the level of individual differences. We assessed 5- to 11-year-old children's working memory, inhibitory control, and cognitive flexibility using measures from the National Institutes of Health Toolbox Cognition battery. Individual differences in children's working memory best predicted performance on an analogical mapping task, even when controlling for age, suggesting a fundamental interrelationship between analogical reasoning and working memory development. These findings underscore the need to consider cognitive capacities in comprehensive theories of children's reasoning development. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Connecting long distance: semantic distance in analogical reasoning modulates frontopolar cortex activity.

    Science.gov (United States)

    Green, Adam E; Kraemer, David J M; Fugelsang, Jonathan A; Gray, Jeremy R; Dunbar, Kevin N

    2010-01-01

    Solving problems often requires seeing new connections between concepts or events that seemed unrelated at first. Innovative solutions of this kind depend on analogical reasoning, a relational reasoning process that involves mapping similarities between concepts. Brain-based evidence has implicated the frontal pole of the brain as important for analogical mapping. Separately, cognitive research has identified semantic distance as a key characteristic of the kind of analogical mapping that can support innovation (i.e., identifying similarities across greater semantic distance reveals connections that support more innovative solutions and models). However, the neural substrates of semantically distant analogical mapping are not well understood. Here, we used functional magnetic resonance imaging (fMRI) to measure brain activity during an analogical reasoning task, in which we parametrically varied the semantic distance between the items in the analogies. Semantic distance was derived quantitatively from latent semantic analysis. Across 23 participants, activity in an a priori region of interest (ROI) in left frontopolar cortex covaried parametrically with increasing semantic distance, even after removing effects of task difficulty. This ROI was centered on a functional peak that we previously associated with analogical mapping. To our knowledge, these data represent a first empirical characterization of how the brain mediates semantically distant analogical mapping.

  15. Configurable Analog-Digital Conversion Using the Neural EngineeringFramework

    Directory of Open Access Journals (Sweden)

    Christian G Mayr

    2014-07-01

    Full Text Available Efficient Analog-Digital Converters (ADC are one of the mainstays of mixed-signal integrated circuit design. Besides the conventional ADCs used in mainstream ICs, there have been various attempts in the past to utilize neuromorphic networks to accomplish an efficient crossing between analog and digital domains, i.e. to build neurally inspired ADCs. Generally, these have suffered from the same problems as conventional ADCs, that is they require high-precision, handcrafted analog circuits and are thus not technology portable. In this paper, we present an ADC based on the Neural Engineering Framework (NEF. It carries out a large fraction of the overall ADC process in the digital domain, i.e. it is easily portable across technologies. The analog-digital conversion takes full advantage of the high degree of parallelism inherent in neuromorphic networks, making for a very scalable ADC. In addition, it has a number of features not commonly found in conventional ADCs, such as a runtime reconfigurability of the ADC sampling rate, resolution and transfer characteristic.

  16. Recent advances in carbon nanotube-based electronics

    International Nuclear Information System (INIS)

    Sharma, Prithu; Ahuja, Prerit

    2008-01-01

    CNT-electronics is a field involving synthesis of carbon nanotubes-based novel electronic circuits, comparable to the size of molecules, the practically fundamental size possible. It has brought a new paradigm in science as it has enabled scientists to increase the device integration density tremendously, hence achieving better efficiency and speed. Here we review the state-of-art current research on the applications of CNTs in electronics and present recent results outlining their potential along with illustrating some current concerns in the research field. Unconventional projects such as CNT-based biological sensors, transistors, field emitters, integrated circuits, etc. are taking CNT-based electronics to its extremes. The field holds a promise for mass production of high speed and efficient electronic devices. However, the chemical complexity, reproducibility and other factors make the field a challenging one, which need to be addressed before the field realizes its true potential

  17. Process and circuiting arrangement for the conversion of analog signals to digital signals and digital signals to analog signals

    International Nuclear Information System (INIS)

    Wintzer, K.

    1977-01-01

    Process for analog-to-digital and digital-to-analog conversion in telecommunication systems whose outstations each have an analog transmitter and an analog receiver. The invention illustrates a method of reducing the power demand of the converters at times when no conversion processes take place. (RW) [de

  18. Analogies and the 5E Model

    Science.gov (United States)

    Orgill, Mary Kay; Thomas, Megan

    2007-01-01

    Science classes are full of abstract or challenging concepts that are easier to understand if an analogy is used to illustrate the points. Effective analogies motivate students, clarify students' thinking, help students overcome misconceptions, and give students ways to visualize abstract concepts. When they are used appropriately, analogies can…

  19. A flexible analog memory address list manager/controller for PHENIX

    International Nuclear Information System (INIS)

    Ericson, M.N.; Walker, J.W.; Britton, C.L.; Wintenberg, A.L.; Young, G.R.

    1995-01-01

    A programmable analog memory address list manager/controller has been developed for use with all analog memory-based detector subsystems of PHENIX. The unit provides simultaneous read/write control, cell write-over protection for both a Level-1 trigger decision delay and digitization latency, and re-ordering of AMU addresses following conversion, at a beam crossing rate of 112 ns. Addresses are handled such that up to 5 Level-1 events can be maintained in the AMU without write-over. Data tagging is implemented for handling overlapping and shared beam event data packets. Full usage in all PHENIX analog memory-based detector sub-systems is accomplished by the use of detector-specific programmable parameters -- the number of data samples per Level-1 trigger valid and the swnple spacing. Architectural candidates for the system are discussed with emphasis on implementation implications. Details of the design are presented including design simulations, timing information, and test results from a full implementation using programmable logic devices

  20. A Kolmogorov Complexity View of Analogy: From Logical Modeling to Experimentations

    Science.gov (United States)

    Bayoudh, Meriam; Prade, Henri; Richard, Gilles

    Analogical reasoning is considered as one of the main mechanisms underlying human intelligence and creativity, allowing the paradigm shift essential to a creative process. More specific is the notion of analogical proportion like "2 is to 4 as 5 is to 10" or "read is to reader as lecture is to lecturer": such statements can be precisely described within an algebraic framework. When the proportion holds between concepts as in "engine is to car as heart is to human" or "wine is to France as beer is to England", applying an algebraic framework is less straightforward and a new way to understand analogical proportions on the basis of Kolmogorov complexity theory may seem more appropriate. This viewpoint has been used to develop a classifier detecting analogies in natural language. Despite their apparent difference, it is quite clear that the two viewpoints should be strongly related. In this paper, we investigate the link between a purely abstract view of analogical proportions and a definition based on Kolmogorov complexity theory. This theory is used as a backbone to experiment a classifier of natural language analogies whose results are consistent with the abstract setting.

  1. Plasma analog of particle-pair production

    International Nuclear Information System (INIS)

    Tsidulko, Yu.A.; Berk, H.L.

    1996-09-01

    It is shown that the plasma axial shear flow instability satisfies the Klein-Gordon equation. The plasma instability is then shown to be analogous to spontaneous particle-pair production when a potential energy is present that is greater than twice the particle rest mass energy. Stability criteria can be inferred based on field theoretical conservation laws

  2. Component Processes in Analogical Reasoning

    Science.gov (United States)

    Sternberg, Robert J.

    1977-01-01

    Describes alternative theoretical positions regarding (a) the component information processes used in analogical reasoning and (b) strategies for combining these processes. Also presents results from three experiments on analogical reasoning. (Author/RK)

  3. Spin sensitivity of a channel electron multiplier

    International Nuclear Information System (INIS)

    Scholten, R.E.; McClelland, J.J.; Kelley, M.H.; Celotta, R.J.

    1988-01-01

    We report direct measurements of the sensitivity of a channel electron multiplier to electrons with different spin orientations. Four regions of the multiplier cone were examined using polarized electrons at 100-eV incident energy. Pulse counting and analog modes of operation were both investigated and in each case the observed spin effects were less than 0.5%

  4. Comparative study of digital laser film and analog paper image recordings

    International Nuclear Information System (INIS)

    Lee, K.R.; Cox, G.G.; Templeton, A.W.; Preston, D.F.; Anderson, W.H.; Hensley, K.S.; Dwyer, S.J.

    1987-01-01

    The increase in the use of various imaging modalities demands higher quality and more efficacious analog image recordings. Laser electronic recordings with digital array prints of 4,000 x 5,000 x 12 bits obtained using laser-sensitive film or paper are being evaluated. Dry silver paper recordings are being improved and evaluated. High-resolution paper dot printers are being studied to determine their gray-scale capabilities. The authors evaluated the image quality, costs, clinical utilization, and acceptability of CT scans, MR images, digital subtraction angiograms, digital radiographs, and radionuclide scans recorded by seven different printers (three laser, three silver paper, and one dot) and compared the same features in conventional film recording. This exhibit outlines the technical developments and instrumentation of digital laser film and analog paper recorders and presents the results of the study

  5. Is the link from working memory to analogy causal? No analogy improvements following working memory training gains.

    Directory of Open Access Journals (Sweden)

    J Elizabeth Richey

    Full Text Available Analogical reasoning has been hypothesized to critically depend upon working memory through correlational data, but less work has tested this relationship through experimental manipulation. An opportunity for examining the connection between working memory and analogical reasoning has emerged from the growing, although somewhat controversial, body of literature suggests complex working memory training can sometimes lead to working memory improvements that transfer to novel working memory tasks. This study investigated whether working memory improvements, if replicated, would increase analogical reasoning ability. We assessed participants' performance on verbal and visual analogy tasks after a complex working memory training program incorporating verbal and spatial tasks. Participants' improvements on the working memory training tasks transferred to other short-term and working memory tasks, supporting the possibility of broad effects of working memory training. However, we found no effects on analogical reasoning. We propose several possible explanations for the lack of an impact of working memory improvements on analogical reasoning.

  6. Is the link from working memory to analogy causal? No analogy improvements following working memory training gains.

    Science.gov (United States)

    Richey, J Elizabeth; Phillips, Jeffrey S; Schunn, Christian D; Schneider, Walter

    2014-01-01

    Analogical reasoning has been hypothesized to critically depend upon working memory through correlational data, but less work has tested this relationship through experimental manipulation. An opportunity for examining the connection between working memory and analogical reasoning has emerged from the growing, although somewhat controversial, body of literature suggests complex working memory training can sometimes lead to working memory improvements that transfer to novel working memory tasks. This study investigated whether working memory improvements, if replicated, would increase analogical reasoning ability. We assessed participants' performance on verbal and visual analogy tasks after a complex working memory training program incorporating verbal and spatial tasks. Participants' improvements on the working memory training tasks transferred to other short-term and working memory tasks, supporting the possibility of broad effects of working memory training. However, we found no effects on analogical reasoning. We propose several possible explanations for the lack of an impact of working memory improvements on analogical reasoning.

  7. Is the Link from Working Memory to Analogy Causal? No Analogy Improvements following Working Memory Training Gains

    Science.gov (United States)

    Richey, J. Elizabeth; Phillips, Jeffrey S.; Schunn, Christian D.; Schneider, Walter

    2014-01-01

    Analogical reasoning has been hypothesized to critically depend upon working memory through correlational data [1], but less work has tested this relationship through experimental manipulation [2]. An opportunity for examining the connection between working memory and analogical reasoning has emerged from the growing, although somewhat controversial, body of literature suggests complex working memory training can sometimes lead to working memory improvements that transfer to novel working memory tasks. This study investigated whether working memory improvements, if replicated, would increase analogical reasoning ability. We assessed participants’ performance on verbal and visual analogy tasks after a complex working memory training program incorporating verbal and spatial tasks [3], [4]. Participants’ improvements on the working memory training tasks transferred to other short-term and working memory tasks, supporting the possibility of broad effects of working memory training. However, we found no effects on analogical reasoning. We propose several possible explanations for the lack of an impact of working memory improvements on analogical reasoning. PMID:25188356

  8. Intrinsic Hardware Evolution for the Design and Reconfiguration of Analog Speed Controllers for a DC Motor

    Science.gov (United States)

    Gwaltney, David A.; Ferguson, Michael I.

    2003-01-01

    Evolvable hardware provides the capability to evolve analog circuits to produce amplifier and filter functions. Conventional analog controller designs employ these same functions. Analog controllers for the control of the shaft speed of a DC motor are evolved on an evolvable hardware platform utilizing a second generation Field Programmable Transistor Array (FPTA2). The performance of an evolved controller is compared to that of a conventional proportional-integral (PI) controller. It is shown that hardware evolution is able to create a compact design that provides good performance, while using considerably less functional electronic components than the conventional design. Additionally, the use of hardware evolution to provide fault tolerance by reconfiguring the design is explored. Experimental results are presented showing that significant recovery of capability can be made in the face of damaging induced faults.

  9. Empirical source strength correlations for rans-based acoustic analogy methods

    Science.gov (United States)

    Kube-McDowell, Matthew Tyndall

    JeNo is a jet noise prediction code based on an acoustic analogy method developed by Mani, Gliebe, Balsa, and Khavaran. Using the flow predictions from a standard Reynolds-averaged Navier-Stokes computational fluid dynamics solver, JeNo predicts the overall sound pressure level and angular spectra for high-speed hot jets over a range of observer angles, with a processing time suitable for rapid design purposes. JeNo models the noise from hot jets as a combination of two types of noise sources; quadrupole sources dependent on velocity fluctuations, which represent the major noise of turbulent mixing, and dipole sources dependent on enthalpy fluctuations, which represent the effects of thermal variation. These two sources are modeled by JeNo as propagating independently into the far-field, with no cross-correlation at the observer location. However, high-fidelity computational fluid dynamics solutions demonstrate that this assumption is false. In this thesis, the theory, assumptions, and limitations of the JeNo code are briefly discussed, and a modification to the acoustic analogy method is proposed in which the cross-correlation of the two primary noise sources is allowed to vary with the speed of the jet and the observer location. As a proof-of-concept implementation, an empirical correlation correction function is derived from comparisons between JeNo's noise predictions and a set of experimental measurements taken for the Air Force Aero-Propulsion Laboratory. The empirical correlation correction is then applied to JeNo's predictions of a separate data set of hot jets tested at NASA's Glenn Research Center. Metrics are derived to measure the qualitative and quantitative performance of JeNo's acoustic predictions, and the empirical correction is shown to provide a quantitative improvement in the noise prediction at low observer angles with no freestream flow, and a qualitative improvement in the presence of freestream flow. However, the results also demonstrate

  10. Practical digital electronics for technicians

    CERN Document Server

    Kimber, Will

    2013-01-01

    Practical Digital Electronics for Technicians covers topics on analog and digital signals, logic gates, combinational logic, and Karnaugh mapping. The book discusses the characteristics and types of logic families; sequential systems including latch, bistable circuits, counters and shift registers; Schmitt triggers and multivibrators; and MSI combinational logic systems. Display devices, including LED, LCD and dot matrix display; analog and digital conversion; and examples of and equipment for digital fault finding are also considered. The book concludes by providing answers to the questions

  11. Electronic components and systems

    CERN Document Server

    Dennis, W H

    2013-01-01

    Electronic Components and Systems focuses on the principles and processes in the field of electronics and the integrated circuit. Covered in the book are basic aspects and physical fundamentals; different types of materials involved in the field; and passive and active electronic components such as capacitors, inductors, diodes, and transistors. Also covered in the book are topics such as the fabrication of semiconductors and integrated circuits; analog circuitry; digital logic technology; and microprocessors. The monograph is recommended for beginning electrical engineers who would like to kn

  12. Modern analog filter analysis and design a practical approach

    CERN Document Server

    Raut, R

    2011-01-01

    Starting from the fundamentals, the present book describes methods of designing analog electronic filters and illustrates these methods by providing numerical and circuit simulation programs. The subject matters comprise many concepts and techniques that are not available in other text books on the market. To name a few - principle of transposition and its application in directly realizing current mode filters from well known voltage mode filters; an insight into the technological aspect of integrated circuit components used to implement an integrated circuit filter; a careful blending of basi

  13. From Analog to Digital Medias in Early Childhood Education

    DEFF Research Database (Denmark)

    Brandt, Erika Zimmer

    2015-01-01

    Research aims: The aim of the study is to explore how the encounters between children and their educators alter when the media changes from analog to digital. Relationship to previous research works Tablets and other handheld, electronic devices has become part of everyday life in kindergartens....... Research shows that there are both potential pedagogical difficulties and possibilities connected to using digital media (ex. Thestrup 2015, Tække and Paulsen 2014) Theoretical and conceptual framework: The study is a single case study of an educational experiment (Flyvbjerg 2006). It is carried out...

  14. Analogy between electrochemical behaviour of thick silicon granular electrodes for lithium batteries and fine soils micromechanics

    International Nuclear Information System (INIS)

    Nguyen, B.P.N.; Gaubicher, J.; Lestriez, B.

    2014-01-01

    In this paper we study the influence of the distribution and the shape of the carbon conductive additives on the cyclability of thick silicon based composite electrodes. Results pinpoint the influence of carbon additives is not only to play on the electronic conductivity but also to play on the micromechanics (stress distribution) of the composite films. The lack of correlation between electrochemical performance and the macroscopic electronic conductivity of the pristine electrodes and the observation of repeated drops and jumps in capacity during cycling brought us to make an analogy between the silicon composite electrodes and cohesive granular materials such as fine soils media. Considering the collective mechanical behavior of a stack of silicon particles upon repeated volume variations shed a novel understanding to the electrochemical behavior of composite electrodes based on silicon and alloying materials and tells us how critically important is the design at the different scales (the particle, a few particles, the composite electrode, the cell) to engineer the mechanical stress and strain and improve cycle life

  15. Analogical scaffolding and the learning of abstract ideas in physics: An example from electromagnetic waves

    Directory of Open Access Journals (Sweden)

    Noah D. Finkelstein

    2007-06-01

    Full Text Available This paper describes a model of analogy, analogical scaffolding, which explains present and prior results of student learning with analogies. We build on prior models of representation, blending, and layering of ideas. Extending this model’s explanatory power, we propose ways in which the model can be applied to design a curriculum directed at teaching abstract ideas in physics using multiple, layered analogies. We report on a recent empirical study that motivates this model. Students taught about electromagnetic waves in a curriculum that builds on the model of analogical scaffolding posted substantially greater gains pre- to postinstruction than students taught using a more traditional (non-analogy-based tutorial (21% vs 7%.

  16. 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

  17. A Mixed Analog-Digital Radiation Hard Technology for High Energy Physics Electronics: DMILL~(Durci~Mixte~sur~Isolant~Logico-Lineaire)

    CERN Multimedia

    Lugiez, F; Leray, J; Rouger, M; Fourches, N T; Musseau, O; Potheau, R

    2002-01-01

    %RD29 %title\\\\ \\\\Physics experiments under preparation with the future LHC require a fast, low noise, very rad-hard (>10 Mrad and >10$^{14}$ neutron/cm$^{2}$), mixed analog-digital microelectronics VLSI technology.\\\\ \\\\The DMILL microelectronics technology (RD29) was developed between 1990 and 1995 by a Consortium gathering the CEA and the firm Thomson-TCS, with the collaboration of IN2P3. The goal of the DMILL program, which is now completed, was to provide the High Energy Physics community, space industry, nuclear industry, and other applications, with an industrial very rad-hard mixed analog-digital microelectronics technology.\\\\ \\\\DMILL integrates mixed analog-digital very rad-hard (>10 Mrad and >10$^{14}$ neutron/cm$^{2}$) vertical bipolar, 0.8 $\\mu$m CMOS and 1.2 $\\mu$m PJFET transistors. Its SOI substrate and its dielectric trenches strongly reduce SEU sensitivity and completely eliminate any possibility of latch-up. Its four transistors are optimized to obtain low-noise features. DMILL also integrates...

  18. Combined analog-to-digital converter

    International Nuclear Information System (INIS)

    Zhukov, A.V.; Rzhendinskaya, S.N.

    1983-01-01

    A 10-bit analog-to-digital converter (ADC) designed for operating in spectrometers with time-dependent filters is described. The ADC operation is based on combining the parallel reading and sequential counting methods. At maximum conversion time of 12 μs, timing series frequency of 25 MHz and foUr reference levels the differential nonlinearity withoUt statistical smoothing (maximum relative channel width deviation from average value) is not more than 4%

  19. Synthetic Analogs of Phospholipid Metabolites as Antimalarials.

    Science.gov (United States)

    1979-07-01

    phosphatidic acid analogs containing ether and phosphonate groups; completely non- hydrolyzable lecithin analogs containing phosphinate and ether groups...substance is a completely non- hydrolyzable analog of lecithin containing ether and phosphonate moieties instead of the normally labile carboxylic and...and also ant-i-phospholipase C (clostridial enzyme) activity. This substance Is a completely non- hydrolyzable analog of lecithin containing ether

  20. FGF growth factor analogs

    Science.gov (United States)

    Zamora, Paul O [Gaithersburg, MD; Pena, Louis A [Poquott, NY; Lin, Xinhua [Plainview, NY; Takahashi, Kazuyuki [Germantown, MD

    2012-07-24

    The present invention provides a fibroblast growth factor heparin-binding analog of the formula: ##STR00001## where R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, X, Y and Z are as defined, pharmaceutical compositions, coating compositions and medical devices including the fibroblast growth factor heparin-binding analog of the foregoing formula, and methods and uses thereof.

  1. A CMOS four-quadrant analog current multiplier

    NARCIS (Netherlands)

    Wiegerink, Remco J.

    1991-01-01

    A CMOS four-quadrant analog current multiplier is described. The circuit is based on the square-law characteristic of an MOS transistor and is insensitive to temperature and process variations. The circuit is insensitive to the body effect so it is not necessary to place transistors in individual

  2. High dynamic range isotope ratio measurements using an analog electron multiplier

    Czech Academy of Sciences Publication Activity Database

    Williams, P.; Lorinčík, Jan; Franzreb, K.; Herwig, R.

    2013-01-01

    Roč. 45, č. 1 (2013), s. 549-552 ISSN 0142-2421 R&D Projects: GA MŠk ME 894 Institutional support: RVO:67985882 Keywords : Isotope ratios * electron multiplier * dynamic range Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.393, year: 2013

  3. From exemplar to grammar: a probabilistic analogy-based model of language learning.

    Science.gov (United States)

    Bod, Rens

    2009-07-01

    While rules and exemplars are usually viewed as opposites, this paper argues that they form end points of the same distribution. By representing both rules and exemplars as (partial) trees, we can take into account the fluid middle ground between the two extremes. This insight is the starting point for a new theory of language learning that is based on the following idea: If a language learner does not know which phrase-structure trees should be assigned to initial sentences, s/he allows (implicitly) for all possible trees and lets linguistic experience decide which is the "best" tree for each sentence. The best tree is obtained by maximizing "structural analogy" between a sentence and previous sentences, which is formalized by the most probable shortest combination of subtrees from all trees of previous sentences. Corpus-based experiments with this model on the Penn Treebank and the Childes database indicate that it can learn both exemplar-based and rule-based aspects of language, ranging from phrasal verbs to auxiliary fronting. By having learned the syntactic structures of sentences, we have also learned the grammar implicit in these structures, which can in turn be used to produce new sentences. We show that our model mimicks children's language development from item-based constructions to abstract constructions, and that the model can simulate some of the errors made by children in producing complex questions. Copyright © 2009 Cognitive Science Society, Inc.

  4. Structure problems in the analog computation

    International Nuclear Information System (INIS)

    Braffort, P.L.

    1957-01-01

    The recent mathematical development showed the importance of elementary structures (algebraic, topological, etc.) in abeyance under the great domains of classical analysis. Such structures in analog computation are put in evidence and possible development of applied mathematics are discussed. It also studied the topological structures of the standard representation of analog schemes such as additional triangles, integrators, phase inverters and functions generators. The analog method gives only the function of the variable: time, as results of its computations. But the course of computation, for systems including reactive circuits, introduces order structures which are called 'chronological'. Finally, it showed that the approximation methods of ordinary numerical and digital computation present the same structure as these analog computation. The structure analysis permits fruitful comparisons between the several domains of applied mathematics and suggests new important domains of application for analog method. (M.P.)

  5. Construction and commissioning of the CALICE analog hadron calorimeter prototype

    International Nuclear Information System (INIS)

    Adloff, C.; Karyotakis, Y.

    2010-03-01

    An analog hadron calorimeter (AHCAL) prototype of 5.3 nuclear interaction lengths thickness has been constructed by members of the CALICE Collaboration. The AHCAL prototype consists of a 38-layer sandwich structure of steel plates and highlysegmented scintillator tiles that are read out by wavelength-shifting fibers coupled to SiPMs. The signal is amplified and shaped with a custom-designed ASIC. A calibration/ monitoring system based on LED light was developed to monitor the SiPM gain and to measure the full SiPM response curve in order to correct for non-linearity. Ultimately, the physics goals are the study of hadron shower shapes and testing the concept of particle flow. The technical goal consists of measuring the performance and reliability of 7608 SiPMs. The AHCAL was commissioned in test beams at DESY and CERN. The entire prototype was completed in 2007 and recorded hadron showers, electron showers and muons at different energies and incident angles in test beams at CERN and Fermilab. (orig.)

  6. Construction and commissioning of the CALICA analog hadron calorimeter prototype

    Energy Technology Data Exchange (ETDEWEB)

    Adloff, C.; Karyotakis, Y. [Universite de Savoie, Annecy-le-Vieux (France). Laboratoire d' Annecy-le-Vieux de Physique des Particules, CNRS/IN2P3; Repond, J. [Argonne National Laboratory, Argonne, IL (US)] (and others)

    2010-03-15

    An analog hadron calorimeter (AHCAL) prototype of 5.3 nuclear interaction lengths thickness has been constructed by members of the CALICE Collaboration. The AHCAL prototype consists of a 38-layer sandwich structure of steel plates and highlysegmented scintillator tiles that are read out by wavelength-shifting fibers coupled to SiPMs. The signal is amplified and shaped with a custom-designed ASIC. A calibration/ monitoring system based on LED light was developed to monitor the SiPM gain and to measure the full SiPM response curve in order to correct for non-linearity. Ultimately, the physics goals are the study of hadron shower shapes and testing the concept of particle flow. The technical goal consists of measuring the performance and reliability of 7608 SiPMs. The AHCAL was commissioned in test beams at DESY and CERN. The entire prototype was completed in 2007 and recorded hadron showers, electron showers and muons at different energies and incident angles in test beams at CERN and Fermilab. (orig.)

  7. Construction and Commissioning of the CALICE Analog Hadron Calorimeter Prototype

    CERN Document Server

    Adloff, C.; Repond, J.; Brandt, A.; Brown, H.; De, K.; Medina, C.; Smith, J.; Li, J.; Sosebee, M.; White, A.; Yu, J.; Buanes, T.; Eigen, G.; Mikami, Y.; Miller, O.; Watson, N.K.; Wilson, J.A.; Goto, T.; Mavromanolakis, G.; Thomson, M.A.; Ward, D.R.; Yan, W.; Benchekroun, D.; Hoummada, A.; Khoulaki, Y.; Oreglia, M.; Benyamna, M.; Carloganu, C.; Gay, P.; Ha, J.; Blazey, G.C.; Chakraborty, D.; Dyshkant, A.; Francis, K.; Hedin, D.; Lima, G.; Zutshi, V.; Babkin, V.A.; Bazylev, S.N.; Fedotov, Yu I.; Slepnev, V.M.; Tiapkin, I.A.; Volgin, S.V.; Hostachy, J.Y.; Morin, L.; D'Ascenzo, N.; Cornett, U.; David, D.; Fabbri, R.; Falley, G.; Feege, N.; Gadow, K.; Garutti, E.; Gottlicher, P.; Jung, T.; Karstensen, S.; Korbel, V.; Lucaci-Timoce, A.I.; Lutz, B.; Meyer, N.; Morgunov, V.; Reinecke, M.; Schatzel, S.; Schmidt, S.; Sefkow, F.; Smirnov, P.; Vargas-Trevino, A.; Wattimena, N.; Wendt, O.; Groll, M.; Heuer, R.D.; Richter, S.; Samson, J.; Kaplan, A.; Schultz-Coulon, H.Ch; Shen, W.; Tadday, A.; Bilki, B.; Norbeck, E.; Onel, Y.; Kim, E.J.; Kim, G.; Kim, D.W.; Lee, K.; Lee, S.C.; Kawagoe, K.; Tamura, Y.; Ballin, J.A.; Dauncey, P.D.; Magnan, A.M.; Yilmaz, H.; Zorba, O.; Bartsch, V.; Postranecky, M.; Warren, M.; Wing, M.; Faucci Giannelli, M.; Green, M.G.; Salvatore, F.; Kieffer, R.; Laktineh, I.; Fouz, M.C.; Bailey, D.S.; Barlow, R.J.; Thompson, R.J.; Batouritski, M.; Dvornikov, O.; Shulhevich, Yu; Shumeiko, N.; Solin, A.; Starovoitov, P.; Tchekhovski, V.; Terletski, A.; Bobchenko, B.; Chadeeva, M.; Danilov, M.; Markin, O.; Mizuk, R.; Morgunov, V.; Novikov, E.; Rusinov, V.; Tarkovsky, E.; Andreev, V.; Kirikova, N.; Komar, A.; Kozlov, V.; Smirnov, P.; Soloviev, Y.; Terkulov, A.; Buzhan, P.; Dolgoshein, B.; Ilyin, A.; Kantserov, V.; Kaplin, V.; Karakash, A.; Popova, E.; Smirnov, S.; Baranova, N.; Boos, E.; Gladilin, L.; Karmanov, D.; Korolev, M.; Merkin, M.; Savin, A.; Voronin, A.; Topkar, A.; Frey, A.; Kiesling, C.; Lu, S.; Prothmann, K.; Seidel, K.; Simon, F.; Soldner, C.; Weuste, L.; Bouquet, B.; Callier, S.; Cornebise, P.; Dulucq, F.; Fleury, J.; Li, H.; Martin-Chassard, G.; Richard, F.; de la Taille, Ch.; Poeschl, R.; Raux, L.; Ruan, M.; Seguin-Moreau, N.; Wicek, F.; Anduze, M.; Boudry, V.; Brient, J.C.; Gaycken, G.; Cornat, R.; Jeans, D.; Mora de Freitas, P.; Musat, G.; Reinhard, M.; Rouge, A.; Vanel, J.Ch; Videau, H.; Park, K.H.; Zacek, J.; Cvach, J.; Gallus, P.; Havranek, M.; Janata, M.; Kvasnicka, J.; Marcisovsky, M.; Polak, I.; Popule, J.; Tomasek, L.; Tomasek, M.; Ruzicka, P.; Sicho, P.; Smolik, J.; Vrba, V.; Zalesak, J.; Arestov, Yu; Ammosov, V.; Chuiko, B.; Gapienko, V.; Gilitski, Y.; Koreshev, V.; Semak, A.; Sviridov, Yu; Zaets, V.; Belhorma, B.; Belmir, M.; Baird, A.; Halsall, R.N.; Nam, S.W.; Park, I.H.; Yang, J.; Chai, J.S.; Kim, J.T.; Kim, G.B.; Kim, Y.; Kang, J.; Kwon, Y.J.; Kim, I.; Lee, T.; Park, J.; Sung, J.; Itoh, S.; Kotera, K.; Nishiyama, M.; Takeshita, T.; Weber, S.; Zeitnitz, C.

    2010-01-01

    An analog hadron calorimeter (AHCAL) prototype of 5.3 nuclear interaction lengths thickness has been constructed by members of the CALICE Collaboration. The AHCAL prototype consists of a 38-layer sandwich structure of steel plates and highly-segmented scintillator tiles that are read out by wavelength-shifting fibers coupled to SiPMs. The signal is amplified and shaped with a custom-designed ASIC. A calibration/monitoring system based on LED light was developed to monitor the SiPM gain and to measure the full SiPM response curve in order to correct for non-linearity. Ultimately, the physics goals are the study of hadron shower shapes and testing the concept of particle flow. The technical goal consists of measuring the performance and reliability of 7608 SiPMs. The AHCAL was commissioned in test beams at DESY and CERN. The entire prototype was completed in 2007 and recorded hadron showers, electron showers and muons at different energies and incident angles in test beams at CERN and Fermilab.

  8. Methodology for the digital calibration of analog circuits and systems with case studies

    CERN Document Server

    Pastre, Marc

    2006-01-01

    Methodology for the Digital Calibration of Analog Circuits and Systems shows how to relax the extreme design constraints in analog circuits, allowing the realization of high-precision systems even with low-performance components. A complete methodology is proposed, and three applications are detailed. To start with, an in-depth analysis of existing compensation techniques for analog circuit imperfections is carried out. The M/2+M sub-binary digital-to-analog converter is thoroughly studied, and the use of this very low-area circuit in conjunction with a successive approximations algorithm for digital compensation is described. A complete methodology based on this compensation circuit and algorithm is then proposed. The detection and correction of analog circuit imperfections is studied, and a simulation tool allowing the transparent simulation of analog circuits with automatic compensation blocks is introduced. The first application shows how the sub-binary M/2+M structure can be employed as a conventional di...

  9. Molecular modeling of fentanyl analogs

    Directory of Open Access Journals (Sweden)

    LJILJANA DOSEN-MICOVIC

    2004-11-01

    Full Text Available Fentanyl is a highly potent and clinically widely used narcotic analgesic. A large number of its analogs have been synthesized, some of which (sufentanil and alfentanyl are also in clinical use. Theoretical studies, in recent years, afforded a better understanding of the structure-activity relationships of this class of opiates and allowed insight into the molecular mechanism of the interactions of fentanyl analogs with their receptors. An overview of the current computational techniques for modeling fentanyl analogs, their receptors and ligand-receptor interactions is presented in this paper.

  10. Terrestrial Analogs to Mars

    Science.gov (United States)

    Farr, T. G.; Arcone, S.; Arvidson, R. W.; Baker, V.; Barlow, N. G.; Beaty, D.; Bell, M. S.; Blankenship, D. D.; Bridges, N.; Briggs, G.; Bulmer, M.; Carsey, F.; Clifford, S. M.; Craddock, R. A.; Dickerson, P. W.; Duxbury, N.; Galford, G. L.; Garvin, J.; Grant, J.; Green, J. R.; Gregg, T. K. P.; Guinness, E.; Hansen, V. L.; Hecht, M. H.; Holt, J.; Howard, A.; Keszthelyi, L. P.; Lee, P.; Lanagan, P. D.; Lentz, R. C. F.; Leverington, D. W.; Marinangeli, L.; Moersch, J. E.; Morris-Smith, P. A.; Mouginis-Mark, P.; Olhoeft, G. R.; Ori, G. G.; Paillou, P.; Reilly, J. F., II; Rice, J. W., Jr.; Robinson, C. A.; Sheridan, M.; Snook, K.; Thomson, B. J.; Watson, K.; Williams, K.; Yoshikawa, K.

    2002-08-01

    It is well recognized that interpretations of Mars must begin with the Earth as a reference. The most successful comparisons have focused on understanding geologic processes on the Earth well enough to extrapolate to Mars' environment. Several facets of terrestrial analog studies have been pursued and are continuing. These studies include field workshops, characterization of terrestrial analog sites, instrument tests, laboratory measurements (including analysis of Martian meteorites), and computer and laboratory modeling. The combination of all these activities allows scientists to constrain the processes operating in specific terrestrial environments and extrapolate how similar processes could affect Mars. The Terrestrial Analogs for Mars Community Panel has considered the following two key questions: (1) How do terrestrial analog studies tie in to the Mars Exploration Payload Assessment Group science questions about life, past climate, and geologic evolution of Mars, and (2) How can future instrumentation be used to address these questions. The panel has considered the issues of data collection, value of field workshops, data archiving, laboratory measurements and modeling, human exploration issues, association with other areas of solar system exploration, and education and public outreach activities.

  11. Expert analogy use in a naturalistic setting

    Science.gov (United States)

    Kretz, Donald R.; Krawczyk, Daniel C.

    2014-01-01

    The use of analogy is an important component of human cognition. The type of analogy we produce and communicate depends heavily on a number of factors, such as the setting, the level of domain expertise present, and the speaker's goal or intent. In this observational study, we recorded economics experts during scientific discussion and examined the categorical distance and structural depth of the analogies they produced. We also sought to characterize the purpose of the analogies that were generated. Our results supported previous conclusions about the infrequency of superficial similarity in subject-generated analogs, but also showed that distance and depth characteristics were more evenly balanced than in previous observational studies. This finding was likely due to the nature of the goals of the participants, as well as the broader nature of their expertise. An analysis of analogical purpose indicated that the generation of concrete source examples of more general target concepts was most prevalent. We also noted frequent instances of analogies intended to form visual images of source concepts. Other common purposes for analogies were the addition of colorful speech, inclusion (i.e., subsumption) of a target into a source concept, or differentiation between source and target concepts. We found no association between depth and either of the other two characteristics, but our findings suggest a relationship between purpose and distance; i.e., that visual imagery typically entailed an outside-domain source whereas exemplification was most frequently accomplished using within-domain analogies. Overall, we observed a rich and diverse set of spontaneously produced analogical comparisons. The high degree of expertise within the observed group along with the richly comparative nature of the economics discipline likely contributed to this analogical abundance. PMID:25505437

  12. Expert Analogy Use in a Naturalistic Setting

    Directory of Open Access Journals (Sweden)

    Donald R Kretz

    2014-11-01

    Full Text Available The use of analogy is an important component of human cognition. The type of analogy we produce and communicate depends heavily on a number of factors, such as the setting, the level of domain expertise present, and the speaker’s goal or intent. In this observational study, we recorded economics experts during scientific discussion and examined the categorical distance and structural depth of the analogies they produced. We also sought to characterize the purpose of the analogies that were generated. Our results supported previous conclusions about the infrequency of superficial similarity in subject-generated analogs, but also showed that distance and depth characteristics were more evenly balanced than in previous observational studies. This finding was likely due to the nature of the goals of the participants, as well as the broader nature of their expertise. An analysis of analogical purpose indicated that the generation of concrete source examples of more general target concepts was most prevalent. We also noted frequent instances of analogies intended to form visual images of source concepts. Other common purposes for analogies were the addition of colorful speech, inclusion (i.e., subsumption of a target into a source concept, or differentiation between source and target concepts. We found no association between depth and either of the other two characteristics, but our findings suggest a relationship between purpose and distance; i.e., that visual imagery typically entailed an outside-domain source whereas exemplification was most frequently accomplished using within-domain analogies. Overall, we observed a rich and diverse set of spontaneously produced analogical comparisons. The high degree of expertise within the observed group along with the richly comparative nature of the economics discipline likely contributed to this analogical abundance.

  13. A bilateral frontoparietal network underlies visuospatial analogical reasoning.

    Science.gov (United States)

    Watson, Christine E; Chatterjee, Anjan

    2012-02-01

    Our ability to reason by analogy facilitates problem solving and allows us to communicate ideas efficiently. In this study, we examined the neural correlates of analogical reasoning and, more specifically, the contribution of rostrolateral prefrontal cortex (RLPFC) to reasoning. This area of the brain has been hypothesized to integrate relational information, as in analogy, or the outcomes of subgoals, as in multi-tasking and complex problem solving. Using fMRI, we compared visuospatial analogical reasoning to a control task that was as complex and difficult as the analogies and required the coordination of subgoals but not the integration of relations. We found that analogical reasoning more strongly activated bilateral RLPFC, suggesting that anterior prefrontal cortex is preferentially recruited by the integration of relational knowledge. Consistent with the need for inhibition during analogy, bilateral, and particularly right, inferior frontal gyri were also more active during analogy. Finally, greater activity in bilateral inferior parietal cortex during the analogy task is consistent with recent evidence for the neural basis of spatial relation knowledge. Together, these findings indicate that a network of frontoparietal areas underlies analogical reasoning; we also suggest that hemispheric differences may emerge depending on the visuospatial or verbal/semantic nature of the analogies. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. A new coupling mechanism between two graphene electron waveguides for ultrafast switching

    Science.gov (United States)

    Huang, Wei; Liang, Shi-Jun; Kyoseva, Elica; Ang, Lay Kee

    2018-03-01

    In this paper, we report a novel coupling between two graphene electron waveguides, in analogy the optical waveguides. The design is based on the coherent quantum mechanical tunneling of Rabi oscillation between the two graphene electron waveguides. Based on this coupling mechanism, we propose that it can be used as an ultrafast electronic switching device. Based on a modified coupled mode theory, we construct a theoretical model to analyze the device characteristics, and predict that the switching speed is faster than 1 ps and the on-off ratio exceeds 106. Due to the long mean free path of electrons in graphene at room temperature, the proposed design avoids the limitation of low temperature operation required in the traditional design by using semiconductor quantum-well structure. The layout of our design is similar to that of a standard complementary metal-oxide-semiconductor transistor that should be readily fabricated with current state-of-art nanotechnology.

  15. Electricity electron measurement

    International Nuclear Information System (INIS)

    Kim, Sang Jin; Sung, Rak Jin

    1985-11-01

    This book deals with measurement of electricity and electron. It is divided into fourteen chapters, which depicts basic of electricity measurement, unit and standard, important electron circuit for measurement, instrument of electricity, impedance measurement, power and power amount measurement, frequency and time measurement, waveform measurement, record instrument and direct viewing instrument, super high frequency measurement, digital measurement on analog-digital convert, magnetic measurement on classification by principle of measurement, measurement of electricity application with principle sensors and systematization of measurement.

  16. High-precision analog circuit technology for power supply integrated circuits; Dengen IC yo koseido anarogu kairo gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Nakamori, A.; Suzuki, T.; Mizoe, K. [Fuji Electric Corporate Research and Development,Ltd., Kanagawa (Japan)

    2000-08-10

    With the recent rapid spread of portable electronic appliances, specification requirements such as compact power supply and long operation with batteries have become severer. Power supply ICs (integrated circuits) are required to reduce power consumption in the circuit and perform high-precision control. To meet these requirements, Fuji Electric develops high-precision CMOS (complementary metal-oxide semiconductor) analog technology. This paper describes three analog circuit technologies of a voltage reference, an operational amplifier and a comparator as circuit components particularly important for the precision of power supply ICs. (author)

  17. Using Visual Analogies To Teach Introductory Statistical Concepts

    Directory of Open Access Journals (Sweden)

    Jessica S. Ancker

    2017-07-01

    Full Text Available Introductory statistical concepts are some of the most challenging to convey in quantitative literacy courses. Analogies supplemented by visual illustrations can be highly effective teaching tools. This literature review shows that to exploit the power of analogies, teachers must select analogies familiar to the audience, explicitly link the analog with the target concept, and avert misconceptions by explaining where the analogy fails. We provide guidance for instructors and a series of visual analogies for use in teaching medical and health statistics.

  18. Morphometry of Left Frontal and Temporal Poles Predicts Analogical Reasoning Abilities.

    Science.gov (United States)

    Aichelburg, Clarisse; Urbanski, Marika; Thiebaut de Schotten, Michel; Humbert, Frederic; Levy, Richard; Volle, Emmanuelle

    2016-03-01

    Analogical reasoning is critical for making inferences and adapting to novelty. It can be studied experimentally using tasks that require creating similarities between situations or concepts, i.e., when their constituent elements share a similar organization or structure. Brain correlates of analogical reasoning have mostly been explored using functional imaging that has highlighted the involvement of the left rostrolateral prefrontal cortex (rlPFC) in healthy subjects. However, whether inter-individual variability in analogical reasoning ability in a healthy adult population is related to differences in brain architecture is unknown. We investigated this question by employing linear regression models of performance in analogy tasks and voxel-based morphometry in 54 healthy subjects. Our results revealed that the ability to reason by analogy was associated with structural variability in the left rlPFC and the anterior part of the inferolateral temporal cortex. Tractography of diffusion-weighted images suggested that these 2 regions have a different set of connections but may exchange information via the arcuate fasciculus. These results suggest that enhanced integrative and semantic abilities supported by structural variation in these areas (or their connectivity) may lead to more efficient analogical reasoning. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  19. Macroscopic charge quantization in single-electron devices

    NARCIS (Netherlands)

    Burmistrov, I.S.; Pruisken, A.M.M.

    2010-01-01

    In a recent paper by the authors [I. S. Burmistrov and A. M. M. Pruisken, Phys. Rev. Lett. 101, 056801 (2008)] it was shown that single-electron devices (single-electron transistor or SET) display "macroscopic charge quantization" which is completely analogous to the quantum Hall effect observed on

  20. Recent Total Ionizing Dose Results and Displacement Damage Results for Candidate Spacecraft Electronics for NASA

    Science.gov (United States)

    Cochran, Donna J.; Buchner, Stephen P.; Irwin, Tim L.; LaBel, Kenneth A.; Marshall, Cheryl J.; Reed, Robert A.; Sanders, Anthony B.; Hawkins, Donald K.; Flanigan, Ryan J.; Cox, Stephen R.

    2005-01-01

    We present data on the vulnerability of a variety of candidate spacecraft electronics to total ionizing dose and displacement damage. Devices tested include optoelectronics, digital, analog, linear bipolar devices, hybrid devices, Analog-to- Digital Converters (ADCs), and Digital-to-Analog Converters (DACs), among others. T

  1. Mechatronics by Analogy and Application to Legged Locomotion

    Science.gov (United States)

    Ragusila, Victor

    A new design methodology for mechatronic systems, dubbed as Mechatronics by Analogy (MbA), is introduced and applied to designing a leg mechanism. The new methodology argues that by establishing a similarity relation between a complex system and a number of simpler models it is possible to design the former using the analysis and synthesis means developed for the latter. The methodology provides a framework for concurrent engineering of complex systems while maintaining the transparency of the system behaviour through making formal analogies between the system and those with more tractable dynamics. The application of the MbA methodology to the design of a monopod robot leg, called the Linkage Leg, is also studied. A series of simulations show that the dynamic behaviour of the Linkage Leg is similar to that of a combination of a double pendulum and a spring-loaded inverted pendulum, based on which the system kinematic, dynamic, and control parameters can be designed concurrently. The first stage of Mechatronics by Analogy is a method of extracting significant features of system dynamics through simpler models. The goal is to determine a set of simpler mechanisms with similar dynamic behaviour to that of the original system in various phases of its motion. A modular bond-graph representation of the system is determined, and subsequently simplified using two simplification algorithms. The first algorithm determines the relevant dynamic elements of the system for each phase of motion, and the second algorithm finds the simple mechanism described by the remaining dynamic elements. In addition to greatly simplifying the controller for the system, using simpler mechanisms with similar behaviour provides a greater insight into the dynamics of the system. This is seen in the second stage of the new methodology, which concurrently optimizes the simpler mechanisms together with a control system based on their dynamics. Once the optimal configuration of the simpler system is

  2. The Effect of Combining Analogy-Based Simulation and Laboratory Activities on Turkish Elementary School Students' Understanding of Simple Electric Circuits

    Science.gov (United States)

    Unlu, Zeynep Koyunlu; Dokme, Ibilge

    2011-01-01

    The purpose of this study was to investigate whether the combination of both analogy-based simulation and laboratory activities as a teaching tool was more effective than utilizing them separately in teaching the concepts of simple electricity. The quasi-experimental design that involved 66 seventh grade students from urban Turkish elementary…

  3. Synthesis and anticancer structure activity relationship investigation of cationic anthraquinone analogs.

    Science.gov (United States)

    Shrestha, Jaya P; Fosso, Marina Y; Bearss, Jeremiah; Chang, Cheng-Wei Tom

    2014-04-22

    We have synthesized a series of novel 4,9-dioxo-4,9-dihydro-1H-naphtho[2,3-d][1,2,3]triazol-3-ium salts, which can be viewed as analogs of cationic anthraquinones. Unlike the similar analogs that we have reported previously, these compounds show relatively weak antibacterial activities but exert strong anticancer activities (low μM to nM GI50), in particular, against melanoma, colon cancer, non-small cell lung cancer and central nervous system (CNS) cancer. These compounds are structurally different from their predecessors by having the aromatic group, instead of alkyl chains, directly attached to the cationic anthraquinone scaffold. Further investigation in the structure-activity relationship (SAR) reveals the significant role of electron donating substituents on the aromatic ring in enhancing the anticancer activities via resonance effect. Steric hindrance of these groups is disadvantageous but is less influential than the resonance effect. The difference in the attached groups at N-1 position of the cationic anthraquinone analog is the main structural factor for the switching of biological activity from antibacterial to anticancer. The discovery of these compounds may lead to the development of novel cancer chemotherapeutics. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  4. Analog Readout and Digitizing System for ATLAS TileCal Demonstrator

    CERN Document Server

    Tang, F; The ATLAS collaboration

    2014-01-01

    The TileCal Demonstrator is a prototype for a future upgrade to the ATLAS hadron calorimeter when the Large Hadron Collider increases luminosity in year 2023 (HL-LHC). It will be used for functionality and performance tests. The Demonstrator has 48 channels of upgraded readout and digitizing electronics and a new digital trigger capability, but is backwards-compatible with the present detector system insofar as it also provides analog trigger signals. The Demonstrator is comprised of 4 identical mechanical mini-drawers, each equipped with up to 12 photomultipliers (PMTs). The on-detector electronics includes 45 Front-End Boards, each serving an individual PMT; 4 Main Boards, each to control and digitize up to 12 PMT signals, and 4 corresponding high-speed Daughter Boards serving as data hubs between on-detector and off-detector electronics. The Demonstrator is fully compatible with the present system, accepting ATLAS triggers, timing and slow control commands for the data acquisition, detector control, and de...

  5. Frontopolar cortex mediates abstract integration in analogy.

    Science.gov (United States)

    Green, Adam E; Fugelsang, Jonathan A; Kraemer, David J M; Shamosh, Noah A; Dunbar, Kevin N

    2006-06-22

    Integration of abstractly similar relations during analogical reasoning was investigated using functional magnetic resonance imaging. Activation elicited by an analogical reasoning task that required both complex working memory and integration of abstractly similar relations was compared to activation elicited by a non-analogical task that required complex working memory in the absence of abstract relational integration. A left-sided region of the frontal pole of the brain (BA 9/10) was selectively active for the abstract relational integration component of analogical reasoning. Analogical reasoning also engaged a left-sided network of parieto-frontal regions. Activity in this network during analogical reasoning is hypothesized to reflect categorical alignment of individual component terms that make up analogies. This parieto-frontal network was also engaged by the complex control task, which involved explicit categorization, but not by a simpler control task, which did not involve categorization. We hypothesize that frontopolar cortex mediates abstract relational integration in complex reasoning while parieto-frontal regions mediate working memory processes, including manipulation of terms for the purpose of categorical alignment, that facilitate this integration.

  6. The force of dissimilar analogies in bioethics.

    Science.gov (United States)

    Mertes, Heidi; Pennings, Guido

    2011-04-01

    Although analogical reasoning has long been a popular method of reasoning in bioethics, current literature does not sufficiently grasp its variety. We assert that the main shortcoming is the fact that an analogy's value is often judged on the extent of similarity between the source situation and the target situation, while in (bio)ethics, analogies are often used because of certain dissimilarities rather than in spite of them. We make a clear distinction between dissimilarities that aim to reinforce a similar approach in the source situation and the target situation and dissimilarities that aim to undermine or denounce a similar approach. The former kind of dissimilarity offers the analogy more normative force than if there were no dissimilarities present; this is often overlooked by authors who regard all relevant dissimilarities as detrimental to the analogy's strength. Another observation is that an evaluation of the normative force of an analogy cannot be made independently of moral principles or theories. Without these, one cannot select which elements in an analogy are morally relevant nor determine how they should be interpreted.

  7. 8-bit serial-parallel analog-to-digital converter for fast transient recorder

    International Nuclear Information System (INIS)

    Kulka, Z.; Nadachowski, M.; Zimek, Z.

    1990-08-01

    An 8-bit serial-parallel analog-to-digital converter with a sampling frequency 5 MHz is described. The most important circuits of the device are described and parameters are given. The converter is a central part of a transient recorder type TR-1 designed for recording pulse waveforms in measurements of the kinetics of chemical reactions which are radiation-induced using an electron linear accelerator. 9 refs., 9 figs. (author)

  8. Anti-Plasmodium activity of ceramide analogs

    Directory of Open Access Journals (Sweden)

    Gatt Shimon

    2004-12-01

    Full Text Available Abstract Background Sphingolipids are key molecules regulating many essential functions in eukaryotic cells and ceramide plays a central role in sphingolipid metabolism. A sphingolipid metabolism occurs in the intraerythrocytic stages of Plasmodium falciparum and is associated with essential biological processes. It constitutes an attractive and potential target for the development of new antimalarial drugs. Methods The anti-Plasmodium activity of a series of ceramide analogs containing different linkages (amide, methylene or thiourea linkages between the fatty acid part of ceramide and the sphingoid core was investigated in culture and compared to the sphingolipid analog PPMP (d,1-threo-1-phenyl-2-palmitoylamino-3-morpholino-1-propanol. This analog is known to inhibit the parasite sphingomyelin synthase activity and block parasite development by preventing the formation of the tubovesicular network that extends from the parasitophorous vacuole to the red cell membrane and delivers essential extracellular nutrients to the parasite. Results Analogs containing methylene linkage showed a considerably higher anti-Plasmodium activity (IC50 in the low nanomolar range than PPMP and their counterparts with a natural amide linkage (IC50 in the micromolar range. The methylene analogs blocked irreversibly P. falciparum development leading to parasite eradication in contrast to PPMP whose effect is cytostatic. A high sensitivity of action towards the parasite was observed when compared to their effect on the human MRC-5 cell growth. The toxicity towards parasites did not correlate with the inhibition by methylene analogs of the parasite sphingomyelin synthase activity and the tubovesicular network formation, indicating that this enzyme is not their primary target. Conclusions It has been shown that ceramide analogs were potent inhibitors of P. falciparum growth in culture. Interestingly, the nature of the linkage between the fatty acid part and the

  9. The future of vitamin D analogs

    Directory of Open Access Journals (Sweden)

    Carlien eLeyssens

    2014-04-01

    Full Text Available The active form of vitamin D3, 1,25-dihydroxyvitamin D3, is a major regulator of bone and calcium homeostasis. In addition, this hormone also inhibits the proliferation and stimulates the differentiation of normal as well as malignant cells. Supraphysiological doses of 1,25-dihydroxyvitamin D3 are required to reduce cancer cell proliferation. However, these doses will lead in vivo to calcemic side effects such as hypercalcemia and hypercalciuria. During the last 25 years, many structural analogs of 1,25-dihydroxyvitamin D3 have been synthesized by the introduction of chemical modifications in the A-ring, central CD-ring region or side chain of 1,25-dihydroxyvitamin D3 in the hope to find molecules with a clear dissociation between the beneficial antiproliferative effects and adverse calcemic side effects. One example of such an analog with a good dissociation ratio is calcipotriol (DaivonexR, which is clinically used to treat the hyperproliferative skin disease psoriasis. Other vitamin D analogs were clinically approved for the treatment of osteoporosis or secondary hyperparathyroidism. No vitamin D analog is currently used in the clinic for the treatment of cancer although several analogs have been shown to be potent drugs in animal models of cancer. Omics studies as well as in vitro cell biological experiments unraveled basic mechanisms involved in the antineoplastic effects of vitamin D and its analogs. 1,25-dihydroxyvitamin D3 and analogs act in a cell type- and tissue-specific manner. Moreover, a blockade in the transition of the G0/1 towards S phase of the cell cycle, induction of apoptosis, inhibition of migration and invasion of tumor cells together with effects on angiogenesis and inflammation have been implicated in the pleiotropic effects of 1,25-dihydroxyvitamin D3 and its analogs. In this review we will give an overview of the action of vitamin D analogs in tumor cells and look forward how these compounds could be introduced in the

  10. Specialization of the Rostral Prefrontal Cortex for Distinct Analogy Processes

    Science.gov (United States)

    Gilbert, Sam J.; Benoit, Roland G.; Burgess, Paul W.

    2010-01-01

    Analogical reasoning is central to learning and abstract thinking. It involves using a more familiar situation (source) to make inferences about a less familiar situation (target). According to the predominant cognitive models, analogical reasoning includes 1) generation of structured mental representations and 2) mapping based on structural similarities between them. This study used functional magnetic resonance imaging to specify the role of rostral prefrontal cortex (PFC) in these distinct processes. An experimental paradigm was designed that enabled differentiation between these processes, by temporal separation of the presentation of the source and the target. Within rostral PFC, a lateral subregion was activated by analogy task both during study of the source (before the source could be compared with a target) and when the target appeared. This may suggest that this subregion supports fundamental analogy processes such as generating structured representations of stimuli but is not specific to one particular processing stage. By contrast, a dorsomedial subregion of rostral PFC showed an interaction between task (analogy vs. control) and period (more activated when the target appeared). We propose that this region is involved in comparison or mapping processes. These results add to the growing evidence for functional differentiation between rostral PFC subregions. PMID:20156841

  11. Low-power analog integrated circuits for wireless ECG acquisition systems.

    Science.gov (United States)

    Tsai, Tsung-Heng; Hong, Jia-Hua; Wang, Liang-Hung; Lee, Shuenn-Yuh

    2012-09-01

    This paper presents low-power analog ICs for wireless ECG acquisition systems. Considering the power-efficient communication in the body sensor network, the required low-power analog ICs are developed for a healthcare system through miniaturization and system integration. To acquire the ECG signal, a low-power analog front-end system, including an ECG signal acquisition board, an on-chip low-pass filter, and an on-chip successive-approximation analog-to-digital converter for portable ECG detection devices is presented. A quadrature CMOS voltage-controlled oscillator and a 2.4 GHz direct-conversion transmitter with a power amplifier and upconversion mixer are also developed to transmit the ECG signal through wireless communication. In the receiver, a 2.4 GHz fully integrated CMOS RF front end with a low-noise amplifier, differential power splitter, and quadrature mixer based on current-reused folded architecture is proposed. The circuits have been implemented to meet the specifications of the IEEE 802.15.4 2.4 GHz standard. The low-power ICs of the wireless ECG acquisition systems have been fabricated using a 0.18 μm Taiwan Semiconductor Manufacturing Company (TSMC) CMOS standard process. The measured results on the human body reveal that ECG signals can be acquired effectively by the proposed low-power analog front-end ICs.

  12. Study of the National Science Foundation's South Pole Station as an analogous data base for the logistical support of a Moon laboratory

    Science.gov (United States)

    Hickam, H. H., Jr.

    1993-01-01

    The day will come when the United States will want to return to the Earth's Moon. When that occurs, NASA may look to the Apollo program for technical and inspirational guidance. The Apollo program, however, was designed to be an end to itself--the landing of a man on the Moon and his return safely within the decade of the 1960's. When that was accomplished, the program folded because it was not self-sustaining. The next time we return to the Moon, we should base our planning on a program that is designed to be a sustained effort for an indefinite period. It is the thrust of this report that the South Pole Station of the National Science Foundation can be used to develop analogs for the construction, funding, and logistical support of a lunar base. Other analogs include transportation and national efforts versus international cooperation. A recommended lunar base using the South Pole Station as inspiration is provided, as well as details concerning economical construction of the base over a 22-year period.

  13. Ping-Pong Beam Training with Hybrid Digital-Analog Antenna Arrays

    DEFF Research Database (Denmark)

    Manchón, Carles Navarro; Carvalho, Elisabeth De; Andersen, Jørgen Bach

    2017-01-01

    In this article we propose an iterative training scheme that approximates optimal beamforming between two transceivers equipped with hybrid digital-analog antenna arrays. Inspired by methods proposed for digital arrays that exploit algebraic power iterations, the proposed training procedure...... is based on a series of alternate (ping-pong) transmissions between the two devices over a reciprocal channel. During the transmissions, the devices updates their digital beamformers by conjugation and normalization operations on the received digital signal, while the analog beamformers are progressively...

  14. Enhancing programming logic thinking using analogy mapping

    Science.gov (United States)

    Sukamto, R. A.; Megasari, R.

    2018-05-01

    Programming logic thinking is the most important competence for computer science students. However, programming is one of the difficult subject in computer science program. This paper reports our work about enhancing students' programming logic thinking using Analogy Mapping for basic programming subject. Analogy Mapping is a computer application which converts source code into analogies images. This research used time series evaluation and the result showed that Analogy Mapping can enhance students' programming logic thinking.

  15. Gemini analogs of vitamin D.

    Science.gov (United States)

    Pazos, Gonzalo; Rivadulla, Marcos L; Pérez-García, Xenxo; Gandara, Zoila; Pérez, Manuel

    2014-01-01

    The Gemini analogs are the last significant contribution to the family of vitamin D derivatives in medicine, for the treatment of cancer. The first Gemini analog was characterized by two symmetric side chains at C-20. Following numerous modifications, the most active analog bears a C-23-triple bond, C-26, 27- hexafluoro substituents on one side chain and a terminal trideuteromethylhydroxy group on the other side chain. This progression was possible due to improvements in the synthetic methods for the preparation of these derivatives, which allowed for increasing molecular complexity and complete diastereoselective control at C-20 and the substituted sidechains.

  16. Fault Modeling and Testing for Analog Circuits in Complex Space Based on Supply Current and Output Voltage

    Directory of Open Access Journals (Sweden)

    Hongzhi Hu

    2015-01-01

    Full Text Available This paper deals with the modeling of fault for analog circuits. A two-dimensional (2D fault model is first proposed based on collaborative analysis of supply current and output voltage. This model is a family of circle loci on the complex plane, and it simplifies greatly the algorithms for test point selection and potential fault simulations, which are primary difficulties in fault diagnosis of analog circuits. Furthermore, in order to reduce the difficulty of fault location, an improved fault model in three-dimensional (3D complex space is proposed, which achieves a far better fault detection ratio (FDR against measurement error and parametric tolerance. To address the problem of fault masking in both 2D and 3D fault models, this paper proposes an effective design for testability (DFT method. By adding redundant bypassing-components in the circuit under test (CUT, this method achieves excellent fault isolation ratio (FIR in ambiguity group isolation. The efficacy of the proposed model and testing method is validated through experimental results provided in this paper.

  17. Thiazole-based organic semiconductors for organic electronics.

    Science.gov (United States)

    Lin, Yuze; Fan, Haijun; Li, Yongfang; Zhan, Xiaowei

    2012-06-19

    Over the past two decades, organic semiconductors have been the subject of intensive academic and commercial interests. Thiazole is a common electron-accepting heterocycle due to electron-withdrawing nitrogen of imine (C=N), several moieties based on thiazole have been widely introduced into organic semiconductors, and yielded high performance in organic electronic devices. This article reviews recent developments in the area of thiazole-based organic semiconductors, particularly thiazole, bithiazole, thiazolothiazole and benzobisthiazole-based small molecules and polymers, for applications in organic field-effect transistors, solar cells and light-emitting diodes. The remaining problems and challenges, and the key research direction in near future are discussed. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Atheism and Analogy: Aquinas Against the Atheists

    OpenAIRE

    Linford, Daniel J.

    2014-01-01

    In the 13th century, Thomas Aquinas developed two models for how humans may speak of God - either by the analogy of proportion or by the analogy of proportionality. Aquinas's doctrines initiated a theological debate concerning analogy that spanned several centuries. In the 18th century, there appeared two closely related arguments for atheism which both utilized analogy for their own purposes. In this thesis, I show that one argument, articulated by the French materialist Paul-Henri Thiry Bar...

  19. Is neoclassical microeconomics formally valid? An approach based on an analogy with equilibrium thermodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, Tania; Domingos, Tiago [Environment and Energy Section, DEM, Instituto Superior Tecnico, Avenida Rovisco Pais, 1, 1049-001 Lisboa (Portugal)

    2006-06-10

    The relation between Thermodynamics and Economics is a paramount issue in Ecological Economics. Two different levels can be distinguished when discussing it: formal and substantive. At the formal level, a mathematical framework is used to describe both thermodynamic and economic systems. At the substantive level, thermodynamic laws are applied to economic processes. In Ecological Economics, there is a widespread claim that neoclassical economics has the same mathematical formulation as classical mechanics and is therefore fundamentally flawed because: (1) utility does not obey a conservation law as energy does; (2) an equilibrium theory cannot be used to study irreversible processes. Here, we show that neoclassical economics is based on a wrong formulation of classical mechanics, being in fact formally analogous to equilibrium thermodynamics. The similarity between both formalisms, namely that they are both cases of constrained optimisation, is easily perceived when thermodynamics is looked upon using the Tisza-Callen axiomatisation. In this paper, we take the formal analogy between equilibrium thermodynamics and economic systems far enough to answer the formal criticisms, proving that the formalism of neoclassical economics has irreversibility embedded in it. However, the formal similarity between equilibrium thermodynamics and neoclassical microeconomics does not mean that economic models are in accordance with mass, energy and entropy balance equations. In fact, neoclassical theory suffers from flaws in the substantive integration with thermodynamic laws as has already been fully demonstrated by valuable work done by ecological economists in this field. (author)

  20. Analog filters in nanometer CMOS

    CERN Document Server

    Uhrmann, Heimo; Zimmermann, Horst

    2014-01-01

    Starting from the basics of analog filters and the poor transistor characteristics in nanometer CMOS 10 high-performance analog filters developed by the authors in 120 nm and 65 nm CMOS are described extensively. Among them are gm-C filters, current-mode filters, and active filters for system-on-chip realization for Bluetooth, WCDMA, UWB, DVB-H, and LTE applications. For the active filters several operational amplifier designs are described. The book, furthermore, contains a review of the newest state of research on low-voltage low-power analog filters. To cover the topic of the book comprehensively, linearization issues and measurement methods for the characterization of advanced analog filters are introduced in addition. Numerous elaborate illustrations promote an easy comprehension. This book will be of value to engineers and researchers in industry as well as scientists and Ph.D students at universities. The book is also recommendable to graduate students specializing on nanoelectronics, microelectronics ...

  1. Scientific Analogies and Their Use in Teaching Science

    Science.gov (United States)

    Kipnis, Nahum

    Analogy in science knew its successes and failures, as illustrated by examples from the eighteenth-century physics. At times, some scientists abstained from using a certain analogy on the ground that it had not yet been demonstrated. Several false discoveries in the 18th and early 19th centuries appeared to support their caution. It is now clear that such a position reflected a methodological confusion that resulted from a failure to distinguish between particular and general analogies. Considering analogy as a hierarchical structure provides a new insight into "testing an analogy". While warning science teachers of dangers associated with use of analogy, historical cases and their analysis provided here may encourage them to use analogy more extensively while avoiding misconceptions. An argument is made that the history of science may be a better guide than philosophy of science and cognitive psychology when it concerns the role of analogy in science and in teaching science for understanding.

  2. The enhancement of mathematical analogical reasoning ability of university students through concept attainment model

    Science.gov (United States)

    Angraini, L. M.; Kusumah, Y. S.; Dahlan, J. A.

    2018-05-01

    This study aims to see the enhancement of mathematical analogical reasoning ability of the university students through concept attainment model learning based on overall and Prior Mathematical Knowledge (PMK) and interaction of both. Quasi experiments with the design of this experimental-controlled equivalent group involved 54 of second semester students at the one of State Islamic University. The instrument used is pretest-postest. Kolmogorov-Smirnov test, Levene test, t test, two-way ANOVA test were used to analyse the data. The result of this study includes: (1) The enhancement of the mathematical analogical reasoning ability of the students who gets the learning of concept attainment model is better than the enhancement of the mathematical analogical reasoning ability of the students who gets the conventional learning as a whole and based on PMK; (2) There is no interaction between the learning that is used and PMK on enhancing mathematical analogical reasoning ability.

  3. Analog fault diagnosis by inverse problem technique

    KAUST Repository

    Ahmed, Rania F.

    2011-12-01

    A novel algorithm for detecting soft faults in linear analog circuits based on the inverse problem concept is proposed. The proposed approach utilizes optimization techniques with the aid of sensitivity analysis. The main contribution of this work is to apply the inverse problem technique to estimate the actual parameter values of the tested circuit and so, to detect and diagnose single fault in analog circuits. The validation of the algorithm is illustrated through applying it to Sallen-Key second order band pass filter and the results show that the detecting percentage efficiency was 100% and also, the maximum error percentage of estimating the parameter values is 0.7%. This technique can be applied to any other linear circuit and it also can be extended to be applied to non-linear circuits. © 2011 IEEE.

  4. Transformational and derivational strategies in analogical problem solving.

    Science.gov (United States)

    Schelhorn, Sven-Eric; Griego, Jacqueline; Schmid, Ute

    2007-03-01

    Analogical problem solving is mostly described as transfer of a source solution to a target problem based on the structural correspondences (mapping) between source and target. Derivational analogy (Carbonell, Machine learning: an artificial intelligence approach Los Altos. Morgan Kaufmann, 1986) proposes an alternative view: a target problem is solved by replaying a remembered problem-solving episode. Thus, the experience with the source problem is used to guide the search for the target solution by applying the same solution technique rather than by transferring the complete solution. We report an empirical study using the path finding problems presented in Novick and Hmelo (J Exp Psychol Learn Mem Cogn 20:1296-1321, 1994) as material. We show that both transformational and derivational analogy are problem-solving strategies realized by human problem solvers. Which strategy is evoked in a given problem-solving context depends on the constraints guiding object-to-object mapping between source and target problem. Specifically, if constraints facilitating mapping are available, subjects are more likely to employ a transformational strategy, otherwise they are more likely to use a derivational strategy.

  5. Cost effective electronics for proportional and drift chambers of 'EPECUR' experiment

    International Nuclear Information System (INIS)

    Alekseev, I.G.; Andreev, V.A.; Budkovsky, P.E.; Filimonov, E.A.; Golubev, V.V.; Kanavets, V.P.; Kats, M.M.; Koroleva, L.I.; Kovalev, A.I.; Kozlenko, N.G.; Kozlov, V.S.; Krivshich, A.G.; Kulikov, V.V.; Morozov, B.V.; Nesterov, V.M.; Novinsky, D.V.; Ryltsov, V.V.; Sadler, M.E.; Sakharov, V.A.; Soboyede, D.; Sulimov, A.D.; Sumachev, V.V.; Svirida, D.N.; Trautman, V.Yu.; Walker, E.; Watson, S.

    2007-01-01

    The 'EPECUR' experimental setup is under construction at beam line 322 of the ITEP proton synchrotron. The experiment requires several large area drift chambers to provide reasonable acceptance and fine-pitch proportional chambers for beam particle tracking. The total number of electronic channels is about 7000. A new compact and cost effective readout system for these gaseous detectors was designed, prototyped and tested in the last two years. It is based on modern technologies in analog and digital electronics and data transfer protocols. This paper presents the functional description of the whole DAQ system, including test results as an illustration of its performance

  6. DVD Based Electronic Pulser

    International Nuclear Information System (INIS)

    Morris, Scott J.; Pratt, Rick M.; Hughes, Michael A.; Kouzes, Richard T.; Pitts, W K.; Robinson, Eric E.

    2005-01-01

    This paper describes the design, construction, and testing of a DVD based electronic pulser system (DVDEPS). Such a device is used to generate pulse streams for simulation of both gamma and neutron detector systems. The DVDEPS reproduces a random pulse stream of a full HPGe spectrum as well as a digital pulse stream representing the output of a neutron multiplicity detector. The exchangeable DVD media contains over an hour of data for both detector systems and can contain an arbitrary gamma spectrum and neutron pulse stream. The data is written to the DVD using a desktop computer program from either actual or simulated spectra. The targeted use of the DVDEPS is authentication or validation of monitoring equipment for non-proliferation purposes, but it is also of general use whenever a complex data stream is required. The DVD based pulser combines the storage capacity and simplicity of DVD technology with commonly available electronic components to build a relatively inexpensive yet highly capable testing instrument

  7. Drawing Analogies in Environmental Education

    Science.gov (United States)

    Affifi, Ramsey

    2014-01-01

    Reconsidering the origin, process, and outcomes of analogy-making suggests practices for environmental educators who strive to disengage humans from the isolating illusions of dichotomizing frameworks. We can view analogies as outcomes of developmental processes within which human subjectivity is but an element, threading our sense of self back…

  8. The influence of analogical reasoning instruction on the pedagogical reasoning ability of preservice elementary teachers

    Science.gov (United States)

    James, Mark Charles

    Novice teachers with little prior knowledge of science concepts often resort to teaching science as a litany of jargon and definitions. The primary objective of this study was to establish the efficacy of analogy-based pedagogy on influencing the teaching performance of preservice elementary teachers, a group that has been identified for their particular difficulties in teaching science content. While numerous studies have focused on the efficacy of analogy-based instruction on the conceptual knowledge of learners, this was the first study to focus on the influence of analogy-based pedagogy instruction on the teaching performance of novice teachers. The study utilized a treatment/contrast group design where treatment and contrast groups were obtained from intact sections of a university course on methods of teaching science for preservice elementary education students. Preservice teachers in the treatment group were provided instruction in pedagogy that guided them in the generation of analogies to aid in the explanation phase of their learning cycle lessons. The process of generating and evaluating analogies for use in teaching was instrumental in focusing the preservice teachers' lesson planning efforts on critical attributes in target concepts, and away from misplaced concentrations on jargon and definitions. Teaching performance was primarily analyzed using coded indicants of Shulman's (1986) six stages of pedagogical reasoning ability. The primary data source was preservice teachers' work submitted for a major course assignment where the preservice teachers interviewed an elementary school student to gauge prior knowledge of Newtonian force concepts. The culmination of the semester-long assignment was the design of an individualized lesson that was presented by the preservice teachers to individual elementary school students. The results of this study strongly suggest that instruction in methods to include analogy-based pedagogy within a learning cycle lesson

  9. Dienone-phenol Rearrangement of C-9 Oxygenated Decalinic Dienone and Analogs through B-Ring Cleavage

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Dehydrogenation of 9-hydroxy decalinic enones and analogs with DDQ resulted in a formal dienone-phenol type rearrangement via B-ring cleavage, while the corresponding dienone acetates underwent base-catalyzed formal dienone-phenol type rearrangement analogously.

  10. A prototype BPM electronics module for RHIC

    International Nuclear Information System (INIS)

    Ryan, W.A.; Shea, T.J.; Cerniglia, P.; Degen, C.M.

    1993-01-01

    Prototype components of the VXI-based Beam Position Monitor Electronics for the Relativistic Heavy Ion Collider have been constructed and tested for accuracy, resolution and linearity. The detector, designed solely for single-bunch acquisition, consists of a homodyne detector followed by a sample and hold and Analog-to-Digital Converter. In the final modules, an on-board Digital Signal Processor will provide turn by turn data correction, continuously updated closed-orbit averaging, and circular buffer maintenance. A timing processor allows synchronization of modules to enable correlated data collection

  11. Description of a Mobile-based Electronic Informed Consent System Development.

    Science.gov (United States)

    Hwang, Min-A; Kwak, In Ja

    2015-01-01

    Seoul National University Hospital constructed and implemented a computer-based informed consent system in December 2011. As of 2013, 30% of the informed consents were still filled out manually on paper. Patients and medical staff continuously suggested the implementation of a system for electronic informed consent using portable devices. Therefore, a mobile-based system for electronic informed consent was developed in 2013 to prevent the issues that arise with computer-based systems and paper informed consent. The rate of filling out electronic informed consent increased from 69% to 95% following the implementation of the mobile-based electronic informed consent. This construction of a mobile-based electronic informed consent system would be a good reference point for the development of a mobile-based Electronic Medical Record and for various mobile system environments in medical institutions.

  12. Conjecturing via Reconceived Classical Analogy

    Science.gov (United States)

    Lee, Kyeong-Hwa; Sriraman, Bharath

    2011-01-01

    Analogical reasoning is believed to be an efficient means of problem solving and construction of knowledge during the search for and the analysis of new mathematical objects. However, there is growing concern that despite everyday usage, learners are unable to transfer analogical reasoning to learning situations. This study aims at facilitating…

  13. The potentially neglected culprit of DC surface flashover: electron migration under temperature gradients.

    Science.gov (United States)

    Li, Chuanyang; Hu, Jun; Lin, Chuanjie; He, Jinliang

    2017-06-12

    This report intends to reveal the role of electron migration and its effects in triggering direct current (DC) surface flashover under temperature gradient conditions when using epoxy-based insulating composites. The surface potential and the surface flashover voltage are both measured using insulators that are bridged between two thermo-regulated electrodes. The space charge injection and migration properties under different temperature are detected. The results show that the surface potential rises significantly because of electron migration near the high voltage (HV) electrode under high temperature conditions, thus creating an "analogous ineffective region". The expansion of this "analogous ineffective region" results in most of the voltage drop occurring near the ground electrode, which serves as an important factor triggering positive streamers across the insulation surface. This work is helpful in understanding of DC surface flashover mechanism from a new perspective and also has important significance in design of a suitable DC insulator to avoid surface flashover problem.

  14. Nonadiabatic Dynamics in Single-Electron Tunneling Devices with Time-Dependent Density-Functional Theory

    Science.gov (United States)

    Dittmann, Niklas; Splettstoesser, Janine; Helbig, Nicole

    2018-04-01

    We simulate the dynamics of a single-electron source, modeled as a quantum dot with on-site Coulomb interaction and tunnel coupling to an adjacent lead in time-dependent density-functional theory. Based on this system, we develop a time-nonlocal exchange-correlation potential by exploiting analogies with quantum-transport theory. The time nonlocality manifests itself in a dynamical potential step. We explicitly link the time evolution of the dynamical step to physical relaxation timescales of the electron dynamics. Finally, we discuss prospects for simulations of larger mesoscopic systems.

  15. The Facilitatory Effect of Negative Feedback on the Emergence of Analogical Reasoning Abilities

    Science.gov (United States)

    Ball, Linden J.; Hoyle, Alison M.; Towse, Andrea S.

    2010-01-01

    This paper focuses on the development of analogical reasoning abilities in 5- and 6-year-old children. Our particular interest relates to the way in which analogizing is influenced by the provision of task-based feedback coupled with a self-explanation requirement. Both feedback and self-explanation provide children with opportunities to engage in…

  16. Spectrometric analog-to-digital converter

    International Nuclear Information System (INIS)

    Ormandzhiev, S.I.; Jordanov, V.T.

    1988-01-01

    Converter of digit-by-digit counterbalancing with slipping dial with number of channels equal to total number of states of the main digital-to-analog converter of digit-by-digit counterbalancing systems is presented. Algorithm for selection of digital-to-analog converters, which must be used by means of computer is suggested

  17. How Science Students Can Learn about Unobservable Phenomena Using Computer-Based Analogies

    Science.gov (United States)

    Trey, L.; Khan, S.

    2008-01-01

    A novel instructional computer simulation that incorporates a dynamic analogy to represent Le Chatelier's Principle was designed to investigate the contribution of this feature to students' understanding. Two groups of 12th grade Chemistry students (n=15) interacted with the computer simulation during the study. Both groups did the same…

  18. On the comparison of analog and digital SiPM readout in terms of expected timing performance

    International Nuclear Information System (INIS)

    Gundacker, S.; Auffray, E.; Jarron, P.; Meyer, T.; Lecoq, P.

    2015-01-01

    In time of flight positron emission tomography (TOF-PET) and in particular for the EndoTOFPET-US Project (Frisch, 2013 [1]), and other applications for high energy physics, the multi-digital silicon photomultiplier (MD-SiPM) was recently proposed (Mandai and Charbon, 2012 [2]), in which the time of every single photoelectron is being recorded. If such a photodetector is coupled to a scintillator, the largest and most accurate timing information can be extracted from the cascade of the scintillation photons, and the most probable time of positron emission determined. The readout concept of the MD-SiPM is very different from that of the analog SiPM, where the individual photoelectrons are merely summed up and the output signal fed into the readout electronics. We have developed a comprehensive Monte Carlo (MC) simulation tool that describes the timing properties of the photodetector and electronics, the scintillation properties of the crystal and the light transfer within the crystal. In previous studies we have compared MC simulations with coincidence time resolution (CTR) measurements and found good agreement within less than 10% for crystals of different lengths (from 3 mm to 20 mm) coupled to SiPMs from Hamamatsu. In this work we will use the developed MC tool to directly compare the highest possible time resolution for both the analog and digital readout of SiPMs with different scintillator lengths. The presented studies reveal that the analog readout of SiPMs with microcell signal pile-up and leading edge discrimination can lead to nearly the same time resolution as compared to the maximum likelihood time estimation applied to MD-SiPMs. Consequently there is no real preference for either a digital or analog SiPM for the sake of achieving highest time resolution. However, the best CTR in the analog SiPM is observed for a rather small range of optimal threshold values, whereas the MD-SiPM provides stable CTR after roughly 20 registered photoelectron timestamps in

  19. General and specialized brain correlates for analogical reasoning: A meta-analysis of functional imaging studies.

    Science.gov (United States)

    Hobeika, Lucie; Diard-Detoeuf, Capucine; Garcin, Béatrice; Levy, Richard; Volle, Emmanuelle

    2016-05-01

    Reasoning by analogy allows us to link distinct domains of knowledge and to transfer solutions from one domain to another. Analogical reasoning has been studied using various tasks that have generally required the consideration of the relationships between objects and their integration to infer an analogy schema. However, these tasks varied in terms of the level and the nature of the relationships to consider (e.g., semantic, visuospatial). The aim of this study was to identify the cerebral network involved in analogical reasoning and its specialization based on the domains of information and task specificity. We conducted a coordinate-based meta-analysis of 27 experiments that used analogical reasoning tasks. The left rostrolateral prefrontal cortex was one of the regions most consistently activated across the studies. A comparison between semantic and visuospatial analogy tasks showed both domain-oriented regions in the inferior and middle frontal gyri and a domain-general region, the left rostrolateral prefrontal cortex, which was specialized for analogy tasks. A comparison of visuospatial analogy to matrix problem tasks revealed that these two relational reasoning tasks engage, at least in part, distinct right and left cerebral networks, particularly separate areas within the left rostrolateral prefrontal cortex. These findings highlight several cognitive and cerebral differences between relational reasoning tasks that can allow us to make predictions about the respective roles of distinct brain regions or networks. These results also provide new, testable anatomical hypotheses about reasoning disorders that are induced by brain damage. Hum Brain Mapp 37:1953-1969, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  20. Relations as transformations: implications for analogical reasoning.

    Science.gov (United States)

    Leech, Robert; Mareschal, Denis; Cooper, Richard P

    2007-07-01

    We present two experiments assessing whether the size of a transformation instantiating a relation between two states of the world (e.g., shrinks) is a performance factor affecting analogical reasoning. The first experiment finds evidence of transformation size as a significant factor in adolescent analogical problem solving while the second experiment finds a similar effect on adult analogical reasoning using a markedly different analogical completion paradigm. The results are interpreted as providing evidence for the more general framework that cognitive representations of relations are best understood as mental transformations.

  1. Fermilab accelerator control system: Analog monitoring facilities

    International Nuclear Information System (INIS)

    Seino, K.; Anderson, L.; Smedinghoff, J.

    1987-10-01

    Thousands of analog signals are monitored in different areas of the Fermilab accelerator complex. For general purposes, analog signals are sent over coaxial or twinaxial cables with varying lengths, collected at fan-in boxes and digitized with 12 bit multiplexed ADCs. For higher resolution requirements, analog signals are digitized at sources and are serially sent to the control system. This paper surveys ADC subsystems that are used with the accelerator control systems and discusses practical problems and solutions, and it describes how analog data are presented on the console system

  2. Biophysical and lipofection studies of DOTAP analogs.

    Science.gov (United States)

    Regelin, A E; Fankhaenel, S; Gürtesch, L; Prinz, C; von Kiedrowski, G; Massing, U

    2000-03-15

    In order to investigate the relationship between lipid structure and liposome-mediated gene transfer, we have studied biophysical parameters and transfection properties of monocationic DOTAP analogs, systematically modified in their non-polar hydrocarbon chains. Stability, size and (by means of anisotropy profiles) membrane fluidity of liposomes and lipoplexes were determined, and lipofection efficiency was tested in a luciferase reporter gene assay. DOTAP analogs were used as single components or combined with a helper lipid, either DOPE or cholesterol. Stability of liposomes was a precondition for formation of temporarily stable lipoplexes. Addition of DOPE or cholesterol improved liposome and lipoplex stability. Transfection efficiencies of lipoplexes based on pure DOTAP analogs could be correlated with stability data and membrane fluidity at transfection temperature. Inclusion of DOPE led to rather uniform transfection and anisotropy profiles, corresponding to lipoplex stability. Cholesterol-containing lipoplexes were generally stable, showing high transfection efficiency at low relative fluidity. Our results demonstrate that the efficiency of gene transfer mediated by monocationic lipids is greatly influenced by lipoplex biophysics due to lipid composition. The measurement of fluorescence anisotropy is an appropriate method to characterize membrane fluidity within a defined system of liposomes or lipoplexes and may be helpful to elucidate structure-activity relationships.

  3. Quality of nursing documentation: Paper-based health records versus electronic-based health records.

    Science.gov (United States)

    Akhu-Zaheya, Laila; Al-Maaitah, Rowaida; Bany Hani, Salam

    2018-02-01

    To assess and compare the quality of paper-based and electronic-based health records. The comparison examined three criteria: content, documentation process and structure. Nursing documentation is a significant indicator of the quality of patient care delivery. It can be either paper-based or organised within the system known as the electronic health records. Nursing documentation must be completed at the highest standards, to ensure the safety and quality of healthcare services. However, the evidence is not clear on which one of the two forms of documentation (paper-based versus electronic health records is more qualified. A retrospective, descriptive, comparative design was used to address the study's purposes. A convenient number of patients' records, from two public hospitals, were audited using the Cat-ch-Ing audit instrument. The sample size consisted of 434 records for both paper-based health records and electronic health records from medical and surgical wards. Electronic health records were better than paper-based health records in terms of process and structure. In terms of quantity and quality content, paper-based records were better than electronic health records. The study affirmed the poor quality of nursing documentation and lack of nurses' knowledge and skills in the nursing process and its application in both paper-based and electronic-based systems. Both forms of documentation revealed drawbacks in terms of content, process and structure. This study provided important information, which can guide policymakers and administrators in identifying effective strategies aimed at enhancing the quality of nursing documentation. Policies and actions to ensure quality nursing documentation at the national level should focus on improving nursing knowledge, competencies, practice in nursing process, enhancing the work environment and nursing workload, as well as strengthening the capacity building of nursing practice to improve the quality of nursing care and

  4. Musik som analogi og metafor

    DEFF Research Database (Denmark)

    Bonde, Lars Ole

    2014-01-01

    Indeholder underkapitlerne: 2.5.1 Musik som analogi 2.5.2 Musik som metafor 2.5.3 Musikkens psykologiske funktioner - en taxonomi og metaforisk lytning til fire baroksatser......Indeholder underkapitlerne: 2.5.1 Musik som analogi 2.5.2 Musik som metafor 2.5.3 Musikkens psykologiske funktioner - en taxonomi og metaforisk lytning til fire baroksatser...

  5. Non-analog Monte Carlo estimators for radiation momentum deposition

    International Nuclear Information System (INIS)

    Hykes, Joshua M.; Densmore, Jeffery D.

    2009-01-01

    The standard method for calculating radiation momentum deposition in Monte Carlo simulations is the analog estimator, which tallies the change in a particle's momentum at each interaction with the matter. Unfortunately, the analog estimator can suffer from large amounts of statistical error. In this paper, we present three new non-analog techniques for estimating momentum deposition. Specifically, we use absorption, collision, and track-length estimators to evaluate a simple integral expression for momentum deposition that does not contain terms that can cause large amounts of statistical error in the analog scheme. We compare our new non-analog estimators to the analog estimator with a set of test problems that encompass a wide range of material properties and both isotropic and anisotropic scattering. In nearly all cases, the new non-analog estimators outperform the analog estimator. The track-length estimator consistently yields the highest performance gains, improving upon the analog-estimator figure of merit by factors of up to two orders of magnitude.

  6. Electron commutator on integrated circuits

    International Nuclear Information System (INIS)

    Demidenko, V.V.

    1975-01-01

    The scheme and the parameters of an electron 16-channel contactless commutator based entirely on integrated circuits are described. The device consists of a unit of analog keys based on field-controlled metal-insulator-semiconductor (m.i.s.) transistors, operation amplifier comparators controlling these keys, and a level distributor. The distributor is based on a ''matrix'' scheme and comprises two ring-shaped shift registers plugged in series and a decoder base on two-input logical elements I-NE. The principal dynamical parameters of the circuit are as follows: the control signal delay in the distributor. 50 nsec; the total channel switch-over time, 500-600 nsec. The commutator transmits both constant signals and pulses whose duration reaches tens of nsec. The commutator can be used in data acquisition and processing systems, for shaping complicated signals (for example), (otherwise signals), for simultaneous oscillographing of several signals, and so forth [ru

  7. Smith-Purcell free-electron laser

    International Nuclear Information System (INIS)

    Woods, K.J.; Walsh, J.E.

    1995-01-01

    The term Smith-Purcell free electron laser can be employed generally to describe any coherent radiation source in which a diffraction grating is used to couple an electron beam with the electromagnetic field. To date, most practical developments of this concept have focused on devices which operate in the millimeter spectral regime. In this paper construction of a Smith-Purcell free-electron laser operating in the far-infrared (FIR) region using a novel resonator cavity design and the electron beam from a low energy (0.5-5 MeV) radio-frequency accelerator will be discussed. A tunable source in this region would have many applications and since the beam energy is low, the small size and low overall cost of such a device would make it a laboratory instrument. Current projects which are progressing towards developing a FIR source are the programs at Stanford and CREOL. Both of these projects are using permanent magnet undulators to couple the electron beam with the electromagnetic field. An alternative approach is to use an electron beam passing over a diffraction grating as the radiating mechanism. This phenomenon is known as Smith-Purcell radiation and was first demonstrated for incoherent emission at visible wavelengths. The addition of feedback enhances the stimulated component of the emission which leads to the growth of coherence. Recent calculations for spontaneous emission have shown that the wiggler parameter and the grating efficiency are analogous. This result has important implications for the development of a Smith-Purcell FEL because a grating based free-electron laser would offer a greater range of tunability at a lower cost than its wiggler based counterpart

  8. Alternate source term models for Yucca Mountain performance assessment based on natural analog data and secondary mineral solubility

    International Nuclear Information System (INIS)

    Murphy, W.M.; Codell, R.B.

    1999-01-01

    Performance assessment calculations for the proposed high level radioactive waste repository at Yucca Mountain, Nevada, were conducted using the Nuclear Regulatory Commission Total-System Performance Assessment (TPA 3.2) code to test conceptual models and parameter values for the source term based on data from the Pena Blanca, Mexico, natural analog site and based on a model for coprecipitation and solubility of secondary schoepite. In previous studies the value for the maximum constant oxidative alteration rate of uraninite at the Nopal I uranium body at Pena Blanca was estimated. Scaling this rate to the mass of uranium for the proposed Yucca Mountain repository yields an oxidative alteration rate of 22 kg/y, which was assumed to be an upper limit on the release rate from the proposed repository. A second model was developed assuming releases of radionuclides are based on the solubility of secondary schoepite as a function of temperature and solution chemistry. Releases of uranium are given by the product of uranium concentrations at equilibrium with schoepite and the flow of water through the waste packages. For both models, radionuclides other than uranium and those in the cladding and gap fraction were modeled to be released at a rate proportional to the uranium release rate, with additional elemental solubility limits applied. Performance assessment results using the Pena Blanca oxidation rate and schoepite solubility models for Yucca Mountain were compared to the TPA 3.2 base case model, in which release was based on laboratory studies of spent fuel dissolution, cladding and gap release, and solubility limits. Doses calculated using the release rate based on natural analog data and the schoepite solubility models were smaller than doses generated using the base case model. These results provide a degree of confidence in safety predictions using the base case model and an indication of how conservatism in the base case model may be reduced in future analyses

  9. Alternate source term models for Yucca Mountain performance assessment based on natural analog data and secondary mineral solubility

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, W.M.; Codell, R.B.

    1999-07-01

    Performance assessment calculations for the proposed high level radioactive waste repository at Yucca Mountain, Nevada, were conducted using the Nuclear Regulatory Commission Total-System Performance Assessment (TPA 3.2) code to test conceptual models and parameter values for the source term based on data from the Pena Blanca, Mexico, natural analog site and based on a model for coprecipitation and solubility of secondary schoepite. In previous studies the value for the maximum constant oxidative alteration rate of uraninite at the Nopal I uranium body at Pena Blanca was estimated. Scaling this rate to the mass of uranium for the proposed Yucca Mountain repository yields an oxidative alteration rate of 22 kg/y, which was assumed to be an upper limit on the release rate from the proposed repository. A second model was developed assuming releases of radionuclides are based on the solubility of secondary schoepite as a function of temperature and solution chemistry. Releases of uranium are given by the product of uranium concentrations at equilibrium with schoepite and the flow of water through the waste packages. For both models, radionuclides other than uranium and those in the cladding and gap fraction were modeled to be released at a rate proportional to the uranium release rate, with additional elemental solubility limits applied. Performance assessment results using the Pena Blanca oxidation rate and schoepite solubility models for Yucca Mountain were compared to the TPA 3.2 base case model, in which release was based on laboratory studies of spent fuel dissolution, cladding and gap release, and solubility limits. Doses calculated using the release rate based on natural analog data and the schoepite solubility models were smaller than doses generated using the base case model. These results provide a degree of confidence in safety predictions using the base case model and an indication of how conservatism in the base case model may be reduced in future analyses.

  10. AMIC: an expandable integrated analog front-end for light distribution moments analysis

    OpenAIRE

    SPAGGIARI, MICHELE; Herrero Bosch, Vicente; Lerche, Christoph Werner; Aliaga Varea, Ramón José; Monzó Ferrer, José María; Gadea Gironés, Rafael

    2011-01-01

    In this article we introduce AMIC (Analog Moments Integrated Circuit), a novel analog Application Specific Integrated Circuit (ASIC) front-end for Positron Emission Tomography (PET) applications. Its working principle is based on mathematical analysis of light distribution through moments calculation. Each moment provides useful information about light distribution, such as energy, position, depth of interaction, skewness (deformation due to border effect) etc. A current buffer delivers a cop...

  11. Design and Simulation of Seido Buffer for Analog to Digital Converter (ADC) on Multichannel Analyzer (MCA) Application

    International Nuclear Information System (INIS)

    Harzawadi Hasim; Maslina Ibrahim; Nolida Yusop; Mohd Ashhar Khalid

    2011-01-01

    Most of our electronic equipment has buffer, thus this make buffer as one of importance in electronic gadget. This paper introduced Single Ended Input Differential Output (SEIDO) buffer to predict the bias at approximately 2.5 V. For this purpose, the input range between -1 mV to 4 V was implemented. The software used to cascade SEIDO buffer is called LTspice IV; an open source software developed by Linear Technology Incorporation. The component involve in this development was Operational Amplifier (OP AMP) AD826 from Analog Devices Incorporation, capacitor and resistor. Kirchhoffs Current Law and Kirchhoffs Voltage Law was applied to calculated voltage gain and biasing voltage. All design has been verified by LTspice IV. The result produced from simulation was between -0.3 V to 6.3 V with bias roughly at 2.5 V. These results prove that it was capable to drive Analog Digital Converter (ADC) that can subsequently apply for Multichannel Analyzer (MCA). (author)

  12. Analog-to-digital conversion using custom CMOS analog memory for the EOS time projection chamber

    International Nuclear Information System (INIS)

    Lee, K.L.; Arthur, A.A.; Jones, R.W.; Matis, H.S.; Nakamura, M.; Kleinfelder, S.A.; Ritter, H.G.; Wienman, H.H.

    1990-01-01

    This paper describes the multiplexing scheme of custom CMOS analog memory integrated circuits, 16 channels x 256 cells, into analog to digital converters (ADC's) to handle 15,360 signal channels of a time projection, chamber detector system. Primary requirements of this system are high density, low power and large dynamic range. The analog memory device multiplexing scheme was designed to digitize the information stored in the memory cells. The digitization time of the ADC's and the settling times for the memory unit were carefully interleaved to optimize the performance and timing during the multiplexing operation. This kept the total number of ADC's, a costly and power dissipative component, to an acceptable minimum

  13. Upgrade Analog Readout and Digitizing System for ATLAS TileCal Demonstrator

    CERN Document Server

    Tang, F; Anderson, K; Bohm, C; Hildebrand, K; Muschter, S; Oreglia, M

    2015-01-01

    The TileCal Demonstrator is a prototype for a future upgrade to the ATLAS hadron calorimeter when the Large Hadron Collider increases luminosity in year 2023 (HL-LHC). It will be used for functionality and performance tests. The Demonstrator has 48 channels of upgraded readout and digitizing electronics and a new digital trigger capability, but is backwards-compatible with the present detector system insofar as it also provides analog trigger signals. The Demonstrator is comprised of 4 identical mechanical mini-drawers, each equipped with up to 12 photomultipliers (PMTs). The on-detector electronics includes 45 Front-End Boards, each serving an individual PMT; 4 Main Boards, each to control and digitize up to 12 PMT signals, and 4 corresponding high-speed Daughter Boards serving as data hubs between on-detector and off-detector electronics. The Demonstrator is fully compatible with the present system, accepting ATLAS triggers, timing and slow control commands for the data acquisition, detector control, and de...

  14. Initial results for compressive sensing in electronic support receiver systems

    CSIR Research Space (South Africa)

    Du Plessis, WP

    2011-04-01

    Full Text Available determined by the antenna and microwave system comprising the transmitter and receiver, while the instantaneous bandwidth is mainly determined by the Analog-to-Digital Converter (ADC) in the receiver. A radar can thus operate at any frequency within its... Electronic/Electromagnetic Support Measures (ESM) was used historically [1], [2]. Modern ES receiver systems are based on digital receivers allowing powerful signal processing techniques to be used [3], [4]. Recent developments in sampling technology...

  15. Cyclotron motion in a microwave cavity: an analog of the Lamb shift

    International Nuclear Information System (INIS)

    Brown, L.S.

    1985-09-01

    The interaction of a bound electron with the radiation field produced by the image charges that represent a surrounding metallic cavity produces a shift in its orbital frequency and in its radiative decay time. This is an analog to the Lamb shift in atomic systems, but it is purely a classical effect. We outline the calculation of the frequency shift and the change in the damping constant for a cyclotron motion at the midpoint of a lossy, cylindrical cavity

  16. Electronic voltage and current transformers testing device.

    Science.gov (United States)

    Pan, Feng; Chen, Ruimin; Xiao, Yong; Sun, Weiming

    2012-01-01

    A method for testing electronic instrument transformers is described, including electronic voltage and current transformers (EVTs, ECTs) with both analog and digital outputs. A testing device prototype is developed. It is based on digital signal processing of the signals that are measured at the secondary outputs of the tested transformer and the reference transformer when the same excitation signal is fed to their primaries. The test that estimates the performance of the prototype has been carried out at the National Centre for High Voltage Measurement and the prototype is approved for testing transformers with precision class up to 0.2 at the industrial frequency (50 Hz or 60 Hz). The device is suitable for on-site testing due to its high accuracy, simple structure and low-cost hardware.

  17. A Cherenkov camera with integrated electronics based on the 'Smart Pixel' concept

    International Nuclear Information System (INIS)

    Bulian, Norbert; Hirsch, Thomas; Hofmann, Werner; Kihm, Thomas; Kohnle, Antje; Panter, Michael; Stein, Michael

    2000-01-01

    An option for the cameras of the HESS telescopes, the concept of a modular camera based on 'Smart Pixels' was developed. A Smart Pixel contains the photomultiplier, the high voltage supply for the photomultiplier, a dual-gain sample-and-hold circuit with a 14 bit dynamic range, a time-to-voltage converter, a trigger discriminator, trigger logic to detect a coincidence of X=1...7 neighboring pixels, and an analog ratemeter. The Smart Pixels plug into a common backplane which provides power, communicates trigger signals between neighboring pixels, and holds a digital control bus as well as an analog bus for multiplexed readout of pixel signals. The performance of the Smart Pixels has been studied using a 19-pixel test camera

  18. Mathematical analogies in physics. Thin-layer wave theory

    Directory of Open Access Journals (Sweden)

    José M. Carcione

    2014-03-01

    Full Text Available Field theory applies to elastodynamics, electromagnetism, quantum mechanics, gravitation and other similar fields of physics, where the basic equations describing the phenomenon are based on constitutive relations and balance equations. For instance, in elastodynamics, these are the stress-strain relations and the equations of momentum conservation (Euler-Newton law. In these cases, the same mathematical theory can be used, by establishing appropriate mathematical equivalences (or analogies between material properties and field variables. For instance, the wave equation and the related mathematical developments can be used to describe anelastic and electromagnetic wave propagation, and are extensively used in quantum mechanics. In this work, we obtain the mathematical analogy for the reflection/refraction (transmission problem of a thin layer embedded between dissimilar media, considering the presence of anisotropy and attenuation/viscosity in the viscoelastic case, conductivity in the electromagnetic case and a potential barrier in quantum physics (the tunnel effect. The analogy is mainly illustrated with geophysical examples of propagation of S (shear, P (compressional, TM (transverse-magnetic and TE (transverse-electric waves. The tunnel effect is obtained as a special case of viscoelastic waves at normal incidence.

  19. Structuring students’ analogical reasoning in solving algebra problem

    Science.gov (United States)

    Lailiyah, S.; Nusantara, T.; Sa'dijah, C.; Irawan, E. B.; Kusaeri; Asyhar, A. H.

    2018-01-01

    The average achievement of Indonesian students’ mathematics skills according to Benchmark International Trends in Mathematics and Science Study (TIMSS) is ranked at the 38th out of 42 countries and according to the survey result in Program for International Student Assessment (PISA) is ranked at the 64th out of 65 countries. The low mathematics skill of Indonesian student has become an important reason to research more deeply about reasoning and algebra in mathematics. Analogical reasoning is a very important component in mathematics because it is the key to creativity and it can make the learning process in the classroom become effective. The major part of the analogical reasoning is about structuring including the processes of inferencing and decision-making happens. Those processes involve base domain and target domain. Methodologically, the subjects of this research were 42 students from class XII. The sources of data were derived from the results of thinks aloud, the transcribed interviews, and the videos taken while the subject working on the instruments and interviews. The collected data were analyzed using qualitative techniques. The result of this study described the structuring characteristics of students’ analogical reasoning in solving algebra problems from all the research subjects.

  20. Analogies in optics and micro electronics selected contributions on recent developments

    CERN Document Server

    Lenstra, Daan

    1990-01-01

    This book gives an account of a number of recent developments in two different subfields of research, optics and micro--electronics. The leading principle in presenting them together in one book is the striking similarity between a variety of notions in these two research areas. We mention in this respect tunneling, quantum interference and localization, which are important concepts in quantummechanics and more specifically in condensed matter physics. Miniaturization in solid state engineering has led to new phenomena in which these concepts play their significant roles. As it is the wave character of electrons which is strongly emphasized in these phenomena one's attention is quite naturally directed to the field of optics in which the above quantum-mechanical notions all seem to have their direct classical wavemechanical counterparts. Both micro--electronics and optics have been and still are in a mode of intensifying activity. The possibilities to technically "translate" devices developed within one resea...

  1. Analog of electromagnetically induced transparency at terahertz frequency based on a bilayer-double-H-metamaterial

    Science.gov (United States)

    Wang, Yue'e.; Li, Zhi; Hu, Fangrong

    2018-01-01

    We designed a bilayer-double-H-metamaterials (BDHM) composed of two layers of metal and two layers of dielectric to analog a spectral response of electromagnetically induced transparency (EIT) at terahertz frequency. By changing the incident angle, the BDHM exhibits an EIT-like spectral response. The tunable spectral performances and modulation mechanism of the transparent peak are theoretically investigated using full-wave electromagnetic simulation software. The physical mechanism of the EIT-like effect is based on the constructive and destructive interference between the induced electrical dipoles. Our work provides a new way to realize the EIT-like effect only by changing the incident angles of the metamaterials. The potential applications include tunable filters, sensors, attenuators, switches, and so on.

  2. NASA HRP Immunology Discipline - Use of Terrestrial Analogs

    Science.gov (United States)

    Crucian, Brian

    2014-01-01

    Due to the cost and operational constraints, as well as technical implementation limitations, it is desirous to perform relevant space physiology investigations first in terrestrial 'space analogs'. This is particularly true for initial investigations, which may then provide appropriate focus for subsequent flight investigations, or for mechanistic investigations that simply cannot be performed during spaceflight. Appropriate analog choice is extremely important. There are a wide variety of terrestrial space analogs, each relevant to a particular physiological discipline (or disciplines) and each with a particular fidelity (or lack thereof) to spaceflight, and each with unique operational constraints. The HRP Immunology Discipline is tasked with managing the HRP Risk concerning clinical risk for Astronaut crews related to spaceflight-associated immune dysregulation. Such dysregulation has been documented to occur during spaceflight, and found to persist for the duration of a 6-month ISS mission. Studies continue to characterize the onorbit phenomenon, but it generally consists of diminished immunocyte function, dysregulated cytokine profiles, and persistent herpesvirus reactivation. Causes are thought to synergistically include microgravity, psychological or physiological stress, radiation, and/or circadian misalignment. An appropriate terrestrial analog for immune dysregulation would replicate as many of these influences as possible. Such analogs may include clinostat or bioreactor cell culture (microgravity), hindlimb suspension (stress, fluid shifts, hypokinesis), or human deployment to remote or extreme environments (isolation, stress, circadian). Also, the laboratory setting may be used as an analog, or to augment analogs, such as sleep deprivation/misalignment or human centrifugation to replicate gravitational stress. As an appropriate example of a NASA Disciplines use of Terrestrial space analogs, this talk will discuss spaceflight associated immune

  3. The Development of Analogical Reasoning Processes.

    Science.gov (United States)

    Sternberg, Robert J.; Rifkin, Bathsheva

    1979-01-01

    Two experiments were conducted to test the generalizability to children of a theory of analogical reasoning processes, originally proposed for adults, and to examine the development of analogical reasoning processes in terms of five proposed sources of cognitive development. (MP)

  4. Karakterisasi Mutu dan Nilai Gizi Nasi Mocaf dari Beras Analog - (Characterization of Quality and Nutrition Value of Cooked Rice Mocaf from Rice Analog

    Directory of Open Access Journals (Sweden)

    Enny Hawani Loebis

    2017-06-01

    Full Text Available Dependence on rice consumption needs to be reduced to overcome the problems of rice supply and health problems. Alternative proposed is producing mocaf-based rice analog. This research aims to study the quality characterization and nutritional value of mocaf-based rice analog. Rice mocaf was made based on mixture of mocaf, rice flour, water and palm oil using variable: 50, 60 and 70% mocaf.  Mocaf rice then cooked by using rice cooker, steamer or microwave. The results showed mocaf rice 60% yield highest calorific value.  The best cooking method  was steaming that resulted nutrient content and calorific value consisting of 49.15% water; 2.05% fat; 2.09% protein; 46.45% carbohydrate; 35.8 mg/kg of iron; 403.4 mg/kg of potassium; 193.8 mg/kg of calcium, 2.0 mg/kg of vitamin B1 and 212.53 ca/100 g calorific value.Keywords: mocaf, nutritional value, quality characterisation, rice ABSTRAKKetergantungan pada konsumsi beras perlu dikurangi untuk mengatasi permasalahan pasokan beras dan masalah kesehatan. Alternatif yang dapat diusulkan adalah dengan pembuatan beras analog berbasis mocaf. Penelitian ini bertujuan mempelajari karakterisasi mutu dan nilai gizi nasi mocaf dari beras analog. Beras mocaf dibuat berdasarkan campuran mocaf, tepung beras, air dan minyak goreng sawit, dengan komposisi mocaf  50, 60 dan 70%. Beras mocaf kemudian dimasak dengan cara menggunakan rice cooker, pengukusan atau microwave. Hasil penelitian menunjukkan beras mocaf 60% menghasilkan nasi mocaf dengan nilai kalori tertinggi. Pemasakan terbaik adalah dengan cara pengukusan dengan kandungan gizi dan nilai kalori yang dihasilkan terdiri dari 49,15%  air; 2,05% lemak; 2,09% protein; 46,45% karbohidrat; 35,8 mg/kg besi; 403,4 mg/kg kalium; 193,8 mg/kg kalsium, 2,0 mg/kg vitamin B1 dan 212,53 kal/100 g nilai kalori.Kata kunci: beras, karakterisasi mutu, mocaf, nilai gizi

  5. Student Analogy Reasons When Solving Area Concepts in Pyramids and Prisms

    Science.gov (United States)

    Mashuri, A.; Sudjadi, I.; Pramudya, I.; Gembong, S.

    2017-09-01

    The purpose of this study is to describe the reasoning of students’ analogies in solving the broad concept problem in pyramids and prisms. This research method using descriptive qualitative. Data collection uses analogous reasoning tests and interviews. After that tested to 32 students of Junior High School. Based on the results of the analysis can be concluded that (1) 16% of students solve the problem of source and target problem correctly. (2) 29% of students correctly solve source problems and target problems incorrectly. (3) 55% solve source problems and target problems wrong. This is because students tend to memorize formulas not using analogy reasoning to solve new problems. Finally, the students have difficulties in solving new problems, because students are not accustomed to using the experience they have gained to solve new problems.

  6. Analog electronic model of the lobster pyloric central pattern generator

    Energy Technology Data Exchange (ETDEWEB)

    Volkovskii, A [Institute for Nonlinear Science, University of California San Diego, CA (United States); Brugioni, S [Institute for Nonlinear Science, University of California San Diego, CA (United States); Istituto Nazionale di Ottica Applicata Largo E. Fermi 6 50125 Florence (Italy); Levi, R [Institute for Nonlinear Science, University of California San Diego, CA (United States); Rabinovich, M [Institute for Nonlinear Science, University of California San Diego, CA (United States); Selverston, A [Institute for Nonlinear Science, University of California San Diego, CA (United States); Abarbane, H D I [Institute for Nonlinear Science, University of California San Diego, CA (United States)

    2005-01-01

    An electronic circuit intended to simulate the nonlinear dynamics of a simplified 3-cell model of the pyloric central pattern generator in California spiny lobster stomato gastric ganglion is presented. The model employs the synaptic phase locked loop (SPLL) concept where the frequency of oscillations of a postsynaptic cell is mainly controlled by the synaptic current which depends on the phase shift between the oscillations. The theoretical study showed that the system has a stable steady state with correct phase shifts between the oscillations and that this regime is stable when the frequency of the pacemaker cell is varied over a wide range. The main bifurcations in the system were studied analytically, in computer simulations, and in experiments with the electronic circuit. The experimental measurements are in good agreement with the expectations of the theoretical model.

  7. Design and Analysis of Reconfigurable Analog System

    Science.gov (United States)

    2011-02-01

    34010010" �" �" �" �" �" �" �±" N3 N2 N± P1 P2 P3 * Current sources $RR = 1; *Ramp Rate (slope of the...2008/12/12/31e83bac-500f-4182- acca -4d360295fd9c.pdf, Analog Devices, Analog Dialogue 39-06, June 2005. [15] D. A. Johns, K. Martin "Analog Integrated

  8. Silicon analog components device design, process integration, characterization, and reliability

    CERN Document Server

    El-Kareh, Badih

    2015-01-01

    This book covers modern analog components, their characteristics, and interactions with process parameters. It serves as a comprehensive guide, addressing both the theoretical and practical aspects of modern silicon devices and the relationship between their electrical properties and processing conditions. Based on the authors’ extensive experience in the development of analog devices, this book is intended for engineers and scientists in semiconductor research, development and manufacturing. The problems at the end of each chapter and the numerous charts, figures and tables also make it appropriate for use as a text in graduate and advanced undergraduate courses in electrical engineering and materials science.

  9. The use of Antarctic analogs for the Space Exploration Initiative

    Science.gov (United States)

    Roberts, Barney; Lynch, John T.

    1991-01-01

    Potential approaches to the use of the Antarctic as an analog to the lunar and Mars planetary surface segments of the SEI are reviewed. It is concluded that a well-planned and sustained program of ground-based research and testing in environments analogous to the moon and Mars is a rational method for reducing the risks associated with human space missions. Antarctica may provide an ideal setting for testing critical technologies (habitat design, life support, and advanced scientific instrumentation), studying human factors and physiology, and conducting basic scientific research similar to and directly relevant to that planned for the SEI.

  10. Crows spontaneously exhibit analogical reasoning.

    Science.gov (United States)

    Smirnova, Anna; Zorina, Zoya; Obozova, Tanya; Wasserman, Edward

    2015-01-19

    Analogical reasoning is vital to advanced cognition and behavioral adaptation. Many theorists deem analogical thinking to be uniquely human and to be foundational to categorization, creative problem solving, and scientific discovery. Comparative psychologists have long been interested in the species generality of analogical reasoning, but they initially found it difficult to obtain empirical support for such thinking in nonhuman animals (for pioneering efforts, see [2, 3]). Researchers have since mustered considerable evidence and argument that relational matching-to-sample (RMTS) effectively captures the essence of analogy, in which the relevant logical arguments are presented visually. In RMTS, choice of test pair BB would be correct if the sample pair were AA, whereas choice of test pair EF would be correct if the sample pair were CD. Critically, no items in the correct test pair physically match items in the sample pair, thus demanding that only relational sameness or differentness is available to support accurate choice responding. Initial evidence suggested that only humans and apes can successfully learn RMTS with pairs of sample and test items; however, monkeys have subsequently done so. Here, we report that crows too exhibit relational matching behavior. Even more importantly, crows spontaneously display relational responding without ever having been trained on RMTS; they had only been trained on identity matching-to-sample (IMTS). Such robust and uninstructed relational matching behavior represents the most convincing evidence yet of analogical reasoning in a nonprimate species, as apes alone have spontaneously exhibited RMTS behavior after only IMTS training. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Perceptions of Rebuttal Analogy: Politeness and Implications for Persuasion.

    Science.gov (United States)

    Whaley, Bryan B.

    1997-01-01

    States that recent theorizing about the role of analogy in persuasion suggests that "rebuttal" analogy addresses two communicative functions by serving as argument and a method of social attack. Examines message receivers' perceptions of rebuttal analogy and rebuttal analogy users. Finds that participants perceived the communicator using…

  12. Comparative analysis of quasi-linear spectra of organic boron compounds and their heterocyclic and aromatic analogs

    International Nuclear Information System (INIS)

    Klimova, L.A.; Volkova, V.P.; Kugemova, M.E.; Mikhajlov, B.M.

    1976-01-01

    Quasiline absorption and luminescence spectra of polycyclic compounds containing boron, nitrogen, or oxygen atoms have been obtained and studied for the first time. Electron-vibrating spectra of these compounds have been compared with the corresponding spectra of nitrogen- and oxygen-containing heterocycles as well as with spectra of their aromatic analog - phenanthrene. Vibrational analysis of the spectra of all the compounds reveals, within the accuracy limit of measurements, the relative closeness of the vibrational frequencies. However, the great difference between the positions of electron transitions points to a change in π-electron structure of the molecules when heteroatoms are introduced. High sensitivity of the frequency of electron transition to structural changes makes it possible to determine the degree of influence of separate heteroatoms

  13. Elucidating the neurotoxic effects of MDMA and its analogs.

    Science.gov (United States)

    Karuppagounder, Senthilkumar S; Bhattacharya, Dwipayan; Ahuja, Manuj; Suppiramaniam, Vishnu; Deruiter, Jack; Clark, Randall; Dhanasekaran, Muralikrishnan

    2014-04-17

    There is a rapid increase in the use of methylenedioxymethamphetamine (MDMA) and its structural congeners/analogs globally. MDMA and MDMA-analogs have been synthesized illegally in furtive dwellings and are abused due to its addictive potential. Furthermore, MDMA and MDMA-analogs have shown to have induced several adverse effects. Hence, understanding the mechanisms mediating this neurotoxic insult of MDMA-analogs is of immense importance for the public health in the world. We synthesized and investigated the neurotoxic effects of MDMA and its analogs [4-methylenedioxyamphetamine (MDA), 2, 6-methylenedioxyamphetamine (MDMA), and N-ethyl-3, 4-methylenedioxyamphetamine (MDEA)]. The stimulatory or the dopaminergic agonist effects of MDMA and MDMA-analogs were elucidated using the established 6-hydroxydopamine lesioned animal model. Additionally, we also investigated the neurotoxic mechanisms of MDMA and MDMA-analogs on mitochondrial complex-I activity and reactive oxygen species generation. MDMA and MDMA-analogs exhibited stimulatory activity as compared to amphetamines and also induced several behavioral changes in the rodents. MDMA and MDMA-analogs enhanced the reactive oxygen generation and inhibited mitochondrial complex-I activity which can lead to neurodegeneration. Hence the mechanism of neurotoxicity, MDMA and MDMA-analogs can enhance the release of monoamines, alter the monoaminergic neurotransmission, and augment oxidative stress and mitochondrial abnormalities leading to neurotoxicity. Thus, our study will help in developing effective pharmacological and therapeutic approaches for the treatment of MDMA and MDMA-analog abuse. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Potentialities in electronics of new high critical temperature superconductors. Potentialites en electronique des nouveaux supraconducteurs a haute temperature critique

    Energy Technology Data Exchange (ETDEWEB)

    Hartemann, P [Thomson-CSF, 75 - Paris (FR)

    1989-09-01

    The main electronic applications of superconductors involve the signal processing, the electromagnetic wave detection and the magnetometry. Characteristics of devices based on conventional superconductors cooled by liquid helium are given and the changes induced by incorporating high-temperature superconductors are estimated. After a survey of new superconductor properties, the superconducting devices for analog or digital signal processing are reviewed. The gains predicted for high-temperature superconducting analog devices are considered in greater detail. Different sections deal with the infrared or (sub)millimeter wave detection. The most sensitive apparatuses for magnetic measurements are based on SQUIDs. Features of SQUIDs made of granular high-temperature superconducting material samples (grain boundaries behave as barriers of intrinsic junctions) are discussed.

  15. Mechanism of the high transition temperature for the 1111-type iron-based superconductors R FeAsO (R =rare earth ): Synergistic effects of local structures and 4 f electrons

    Science.gov (United States)

    Zhang, Lifang; Meng, Junling; Liu, Xiaojuan; Yao, Fen; Meng, Jian; Zhang, Hongjie

    2017-07-01

    Among the iron-based superconductors, the 1111-type Fe-As-based superconductors REFeAs O1 -xFx (RE = rare earth) exhibit high transition temperatures (Tc) above 40 K. We perform first-principles calculations based on density functional theory with the consideration of both electronic correlations and spin-orbit couplings on rare earths and Fe ions to study the underlying mechanism as the microscopic structural distortions in REFeAsO tuned by both lanthanide contraction and external strain. The electronic structures evolve similarly in both cases. It is found that there exist an optimal structural regime that will not only initialize but also optimize the orbital fluctuations due to the competing Fe-As and Fe-Fe crystal fields. We also find that the key structural features in REFeAsO, such as As-Fe-As bond angle, intrinsically induce the modification of the Fermi surface and dynamic spin fluctuation. These results suggest that the superconductivity is mediated by antiferromagnetic spin fluctuations. Simultaneously, we show that the rare-earth 4 f electrons play important roles on the high transition temperature whose behavior might be analogous to that of the heavy-fermion superconductors. The superconductivity of these 1111-type iron-based superconductors with high-Tc is considered to originate from the synergistic effects of local structures and 4 f electrons.

  16. Low noise monolithic CMOS front end electronics

    International Nuclear Information System (INIS)

    Lutz, G.; Bergmann, H.; Holl, P.; Manfredi, P.F.

    1987-01-01

    Design considerations for low noise charge measurement and their application in CMOS electronics are described. The amplifier driver combination whose noise performance has been measured in detail as well as the analog multiplexing silicon strip detector readout electronics are designed with low power consumption and can be operated in pulsed mode so as to reduce heat dissipation even further in many applications. (orig.)

  17. Studies on transfer ribonucleic acids and related compounds. XXXII. Synthesis of ribonucleotides corresponding to residues 1-5 and 6-10 of tRNAfMet from E. coli and their base conversion analogs.

    Science.gov (United States)

    Ohtsuka, E; Tanaka, T; Ikehara, M

    1979-01-01

    E. Coli tRNAfMet fragments, C-G-C-G-Gp (bases 1-5), U-G-C-G-Gp (base 1 transition, analog) pG-G-C-G-Gp (base 1 transversion analog) and pG-G-s4U-G-Gp (bases 6-10) were synthesized by triester methods using 2'-O-(o-nitrobenzyl) nucleotides including a 3',5'-bisphosphorylated guanosine derivative. The s4U containing pentanucleotide was derived from the pG-G-C-G-Gp by treatment with liquid hydrogen sulfide. Images PMID:390499

  18. Dual-mode operation of 2D material-base hot electron transistors

    KAUST Repository

    Lan, Yann-Wen; Jr., Carlos M. Torres,; Zhu, Xiaodan; Qasem, Hussam; Adleman, James R.; Lerner, Mitchell B.; Tsai, Shin-Hung; Shi, Yumeng; Li, Lain-Jong; Yeh, Wen-Kuan; Wang, Kang L.

    2016-01-01

    Vertical hot electron transistors incorporating atomically-thin 2D materials, such as graphene or MoS2, in the base region have been proposed and demonstrated in the development of electronic and optoelectronic applications. To the best of our knowledge, all previous 2D material-base hot electron transistors only considered applying a positive collector-base potential (V-CB > 0) as is necessary for the typical unipolar hot-electron transistor behavior. Here we demonstrate a novel functionality, specifically a dual-mode operation, in our 2D material-base hot electron transistors (e.g. with either graphene or MoS2 in the base region) with the application of a negative collector-base potential (V-CB < 0). That is, our 2D material-base hot electron transistors can operate in either a hot-electron or a reverse-current dominating mode depending upon the particular polarity of VCB. Furthermore, these devices operate at room temperature and their current gains can be dynamically tuned by varying VCB. We anticipate our multi-functional dual-mode transistors will pave the way towards the realization of novel flexible 2D material-based high-density and low-energy hot-carrier electronic applications.

  19. Dual-mode operation of 2D material-base hot electron transistors

    KAUST Repository

    Lan, Yann-Wen

    2016-09-01

    Vertical hot electron transistors incorporating atomically-thin 2D materials, such as graphene or MoS2, in the base region have been proposed and demonstrated in the development of electronic and optoelectronic applications. To the best of our knowledge, all previous 2D material-base hot electron transistors only considered applying a positive collector-base potential (V-CB > 0) as is necessary for the typical unipolar hot-electron transistor behavior. Here we demonstrate a novel functionality, specifically a dual-mode operation, in our 2D material-base hot electron transistors (e.g. with either graphene or MoS2 in the base region) with the application of a negative collector-base potential (V-CB < 0). That is, our 2D material-base hot electron transistors can operate in either a hot-electron or a reverse-current dominating mode depending upon the particular polarity of VCB. Furthermore, these devices operate at room temperature and their current gains can be dynamically tuned by varying VCB. We anticipate our multi-functional dual-mode transistors will pave the way towards the realization of novel flexible 2D material-based high-density and low-energy hot-carrier electronic applications.

  20. Biomedical sensor design using analog compressed sensing

    Science.gov (United States)

    Balouchestani, Mohammadreza; Krishnan, Sridhar

    2015-05-01

    The main drawback of current healthcare systems is the location-specific nature of the system due to the use of fixed/wired biomedical sensors. Since biomedical sensors are usually driven by a battery, power consumption is the most important factor determining the life of a biomedical sensor. They are also restricted by size, cost, and transmission capacity. Therefore, it is important to reduce the load of sampling by merging the sampling and compression steps to reduce the storage usage, transmission times, and power consumption in order to expand the current healthcare systems to Wireless Healthcare Systems (WHSs). In this work, we present an implementation of a low-power biomedical sensor using analog Compressed Sensing (CS) framework for sparse biomedical signals that addresses both the energy and telemetry bandwidth constraints of wearable and wireless Body-Area Networks (BANs). This architecture enables continuous data acquisition and compression of biomedical signals that are suitable for a variety of diagnostic and treatment purposes. At the transmitter side, an analog-CS framework is applied at the sensing step before Analog to Digital Converter (ADC) in order to generate the compressed version of the input analog bio-signal. At the receiver side, a reconstruction algorithm based on Restricted Isometry Property (RIP) condition is applied in order to reconstruct the original bio-signals form the compressed bio-signals with high probability and enough accuracy. We examine the proposed algorithm with healthy and neuropathy surface Electromyography (sEMG) signals. The proposed algorithm achieves a good level for Average Recognition Rate (ARR) at 93% and reconstruction accuracy at 98.9%. In addition, The proposed architecture reduces total computation time from 32 to 11.5 seconds at sampling-rate=29 % of Nyquist rate, Percentage Residual Difference (PRD)=26 %, Root Mean Squared Error (RMSE)=3 %.

  1. Natural analogs for Yucca Mountain

    International Nuclear Information System (INIS)

    Murphy, W.M.

    1995-01-01

    High-level radioactive waste in the US, spent fuels from commercial reactors and nuclear materials generated by defense activities, will remain potentially hazardous for thousands of years. Demonstrable long-term stability of certain geologic and geochemical systems motivates and sustains the concept that high-level waste can be safely isolated in geologic repositories for requisite periods of time. Each geologic repository is unique in its properties and performance with reguard to isolation of nuclear wastes. Studies of processes analogous to waste-form alteration and radioelement transport in environments analogous to Yucca Mountain are being conducted at two sites, described in this article to illustrate uses of natural analog data: the Nopal I uranium deposit in the Sierra Pena Blanca, Mexico, and the Akrotiri archaeological site on the island of Santorini, Greece

  2. Modular Hybrid Energy Concept Employing a Novel Control Structure Based on a Simple Analog System

    Directory of Open Access Journals (Sweden)

    PETREUS, D.

    2016-05-01

    Full Text Available This paper proposes a novel control topology which enables the setup of a low cost analog system leading to the implementation of a modular energy conversion system. The modular concept is based on hybrid renewable energy (solar and wind and uses high voltage inverters already available on the market. An important feature of the proposed topology is a permanently active current loop, which assures short circuit protection and simplifies the control loops compensation. The innovative analogue solution of the control structure is based on a dedicated integrated circuit (IC for power factor correction (PFC circuits, used in a new configuration, to assure an efficient inverter start-up. The energy conversion system (control structure and maximum power point tracking algorithm is simulated using a new macromodel-based concept, which reduces the usual computational burden of the simulator and achieves high processing speed. The proposed novel system is presented in this article from concept, through the design and implementation stages, is verified through simulation and is validated by experimental results.

  3. Heterostructure-based high-speed/high-frequency electronic circuit applications

    Science.gov (United States)

    Zampardi, P. J.; Runge, K.; Pierson, R. L.; Higgins, J. A.; Yu, R.; McDermott, B. T.; Pan, N.

    1999-08-01

    With the growth of wireless and lightwave technologies, heterostructure electronic devices are commodity items in the commercial marketplace [Browne J. Power-amplifier MMICs drive commercial circuits. Microwaves & RF, 1998. p. 116-24.]. In particular, HBTs are an attractive device for handset power amplifiers at 900 MHz and 1.9 GHz for CDMA applications [Lum E. GaAs technology rides the wireless wave. Proceedings of the 1997 GaAs IC Symposium, 1997. p. 11-13; "Rockwell Ramps Up". Compound Semiconductor, May/June 1997.]. At higher frequencies, both HBTs and p-HEMTs are expected to dominate the marketplace. For high-speed lightwave circuit applications, heterostructure based products on the market for OC-48 (2.5 Gb/s) and OC-192 (10 Gb/s) are emerging [http://www.nb.rockwell.com/platforms/network_access/nahome.html#5.; http://www.nortel.com/technology/opto/receivers/ptav2.html.]. Chips that operate at 40 Gb/ have been demonstrated in a number of research laboratories [Zampardi PJ, Pierson RL, Runge K, Yu R, Beccue SM, Yu J, Wang KC. hybrid digital/microwave HBTs for >30 Gb/s optical communications. IEDM Technical Digest, 1995. p. 803-6; Swahn T, Lewin T, Mokhtari M, Tenhunen H, Walden R, Stanchina W. 40 Gb/s 3 Volt InP HBT ICs for a fiber optic demonstrator system. Proceedings of the 1996 GaAs IC Symposium, 1996. p. 125-8; Suzuki H, Watanabe K, Ishikawa K, Masuda H, Ouchi K, Tanoue T, Takeyari R. InP/InGaAs HBT ICs for 40 Gbit/s optical transmission systems. Proceedings of the 1997 GaAs IC Symposium, 1997. p. 215-8]. In addition to these two markets, another area where heterostructure devices are having significant impact is for data conversion [Walden RH. Analog-to digital convertor technology comparison. Proceedings of the 1994 GaAs IC Symposium, 1994. p. 217-9; Poulton K, Knudsen K, Corcoran J, Wang KC, Nubling RB, Chang M-CF, Asbeck PM, Huang RT. A 6-b, 4 GSa/s GaAs HBT ADC. IEEE J Solid-State Circuits 1995;30:1109-18; Nary K, Nubling R, Beccue S, Colleran W

  4. A multislice theory of electron scattering in crystals including backscattering and inelastic effects.

    Science.gov (United States)

    Spiegelberg, Jakob; Rusz, Ján

    2015-12-01

    In the framework of the slice transition operator technique, a general multislice theory for electron scattering in crystals is developed. To achieve this generalization, we combine the approaches for inelastic scattering derived by Yoshioka [J. Phys. Soc. Jpn. 12, 6 (1957)] and backscattering based on the formalism of Chen and Van Dyck [Ultramicroscopy 70, 29-44 (1997)]. A computational realization of the obtained equations is suggested. The proposed computational scheme is tested on elastic backscattering of electrons, where we consider single backscattering in analogy to the computational scheme proposed by Chen and Van Dyck. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Analogy-Enhanced Instruction: Effects on Reasoning Skills in Science

    Science.gov (United States)

    Remigio, Krisette B.; Yangco, Rosanelia T.; Espinosa, Allen A.

    2014-01-01

    The study examined the reasoning skills of first year high school students after learning general science concepts through analogies. Two intact heterogeneous sections were randomly assigned to Analogy-Enhanced Instruction (AEI) group and Non Analogy-Enhanced (NAEI) group. Various analogies were incorporated in the lessons of the AEI group for…

  6. Analog elements for transuranic chemistries

    International Nuclear Information System (INIS)

    Weimer, W.C.

    1982-01-01

    The analytical technique for measuring trace concentrations of the analog rare earth elements has been refined for optimal detection. The technique has been used to determine the rare earth concentrations in a series of geological and biological materials, including samples harvested from controlled lysimeter investigations. These studies have demonstrated that any of the trivalent rare earth elements may be used as analog elements for the trivalent transuranics, americium and curium

  7. Analogy, explanation, and proof

    Science.gov (United States)

    Hummel, John E.; Licato, John; Bringsjord, Selmer

    2014-01-01

    People are habitual explanation generators. At its most mundane, our propensity to explain allows us to infer that we should not drink milk that smells sour; at the other extreme, it allows us to establish facts (e.g., theorems in mathematical logic) whose truth was not even known prior to the existence of the explanation (proof). What do the cognitive operations underlying the inference that the milk is sour have in common with the proof that, say, the square root of two is irrational? Our ability to generate explanations bears striking similarities to our ability to make analogies. Both reflect a capacity to generate inferences and generalizations that go beyond the featural similarities between a novel problem and familiar problems in terms of which the novel problem may be understood. However, a notable difference between analogy-making and explanation-generation is that the former is a process in which a single source situation is used to reason about a single target, whereas the latter often requires the reasoner to integrate multiple sources of knowledge. This seemingly small difference poses a challenge to the task of marshaling our understanding of analogical reasoning to understanding explanation. We describe a model of explanation, derived from a model of analogy, adapted to permit systematic violations of this one-to-one mapping constraint. Simulation results demonstrate that the resulting model can generate explanations for novel explananda and that, like the explanations generated by human reasoners, these explanations vary in their coherence. PMID:25414655

  8. Analogy, Explanation, and Proof

    Directory of Open Access Journals (Sweden)

    John eHummel

    2014-11-01

    Full Text Available People are habitual explanation generators. At its most mundane, our propensity to explain allows us to infer that we should not drink milk that smells sour; at the other extreme, it allows us to establish facts (e.g., theorems in mathematical logic whose truth was not even known prior to the existence of the explanation (proof. What do the cognitive operations underlying the (inductive inference that the milk is sour have in common with the (deductive proof that, say, the square root of two is irrational? Our ability to generate explanations bears striking similarities to our ability to make analogies. Both reflect a capacity to generate inferences and generalizations that go beyond the featural similarities between a novel problem and familiar problems in terms of which the novel problem may be understood. However, a notable difference between analogy-making and explanation-generation is that the former is a process in which a single source situation is used to reason about a single target, whereas the latter often requires the reasoner to integrate multiple sources of knowledge. This small-seeming difference poses a challenge to the task of marshaling our understanding of analogical reasoning in the service of understanding explanation. We describe a model of explanation, derived from a model of analogy, adapted to permit systematic violations of this one-to-one mapping constraint. Simulation results demonstrate that the resulting model can generate explanations for novel explananda and that, like the explanations generated by human reasoners, these explanations vary in their coherence.

  9. Medical narratives and patient analogs: the ethical implications of electronic patient records.

    Science.gov (United States)

    Kluge, E H

    1999-12-01

    An electronic patient record consists of electronically stored data about a specific patient. It therefore constitutes a data-space. The data may be combined into a patient profile which is relative to a particular specialty as well as phenomenologically unique to the specific professional who constructs the profile. Further, a diagnosis may be interpreted as a path taken by a health care professional with a certain specialty through the data-space relative to the patient profile constructed by that professional. This way of looking at electronic patient records entails certain ethical implications about privacy and accessibility. However, it also permits the construction of artificial intelligence and competence algorithms for health care professionals relative to their specialties.

  10. How the creative use of analogies can shape medical practice.

    Science.gov (United States)

    Prasad, G V Ramesh

    2015-06-01

    Analogical reasoning is central to medical progress, and is either creative or conservative. According to Hofmann et al., conservative analogy relates concepts from old technology to new technologies with emphasis on preservation of comprehension and conduct. Creative analogy however brings new understanding to new technology, brings similarities existing in the source domain to a target domain where they previously had no bearing, and imports something entirely different from the content of the analogy itself. I defend the claim that while conservative analogies are useful by virtue of being comfortable to use from familiarity and experience, and are more easily accepted by society, they only lead to incremental advances in medicine. However, creative analogies are more exciting and productive because they generate previously unexpected associations across widely separated domains, emphasize relations over physical similarities, and structure over superficiality. I use kidney transplantation and anti-rejection medication development as an exemplar of analogical reasoning used to improve medical practice. Anti-rejection medication has not helped highly sensitized patients because of their propensity to rejecting most organs. I outline how conservative analogical reasoning led to anti-rejection medication development, but creative analogical reasoning helped highly sensitized and blood type incompatible patients through domino transplants, by which they obtain a kidney to which they are not sensitized. Creative analogical reasoning is more likely than conservative analogical reasoning to lead to revolutionary progress. While these analogies overlap and creative analogies eventually become conservative, progress is best facilitated by combining conservative and creative analogical reasoning. © 2015 John Wiley & Sons, Ltd.

  11. Atomic electron correlations in intense laser fields

    International Nuclear Information System (INIS)

    DiMauro, L.F.; Sheehy, B.; Walker, B.; Agostini, P.A.

    1998-01-01

    This talk examines two distinct cases in strong optical fields where electron correlation plays an important role in the dynamics. In the first example, strong coupling in a two-electron-like system is manifested as an intensity-dependent splitting in the ionized electron energy distribution. This two-electron phenomenon (dubbed continuum-continuum Autler-Townes effect) is analogous to a strongly coupled two-level, one-electron atom but raises some intriguing questions regarding the exact nature of electron-electron correlation. The second case examines the evidence for two-electron ionization in the strong-field tunneling limit. Although their ability to describe the one-electron dynamics has obtained a quantitative level of understanding, a description of the two (multiple) electron ionization remains unclear

  12. Neural network based electron identification in the ZEUS calorimeter

    International Nuclear Information System (INIS)

    Abramowicz, H.; Caldwell, A.; Sinkus, R.

    1995-01-01

    We present an electron identification algorithm based on a neural network approach applied to the ZEUS uranium calorimeter. The study is motivated by the need to select deep inelastic, neutral current, electron proton interactions characterized by the presence of a scattered electron in the final state. The performance of the algorithm is compared to an electron identification method based on a classical probabilistic approach. By means of a principle component analysis the improvement in the performance is traced back to the number of variables used in the neural network approach. (orig.)

  13. Analogs for transuranic elements

    International Nuclear Information System (INIS)

    Weimer, W.C.; Laul, J.C.; Kutt, J.C.

    1981-01-01

    A combined theoretical and experimental approach is being used to estimate the long-term environmental and biogeochemical behaviors of selected transuranic elements. The objective of this research is to estimate the effect that long-term (hundreds of years) environmental weathering has on the behavior of the transuranic elements americium and curium. This is achieved by investigating the actual behavior of naturally occurring rare earth elements, especially neodymium, that serve as transuranic analogs. Determination of the analog element behavior provides data that can be used to estimate the ultimate availability to man of transuranic materials released into the environment

  14. Graph-based linear scaling electronic structure theory

    Energy Technology Data Exchange (ETDEWEB)

    Niklasson, Anders M. N., E-mail: amn@lanl.gov; Negre, Christian F. A.; Cawkwell, Marc J.; Swart, Pieter J.; Germann, Timothy C.; Bock, Nicolas [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Mniszewski, Susan M.; Mohd-Yusof, Jamal; Wall, Michael E.; Djidjev, Hristo [Computer, Computational, and Statistical Sciences Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Rubensson, Emanuel H. [Division of Scientific Computing, Department of Information Technology, Uppsala University, Box 337, SE-751 05 Uppsala (Sweden)

    2016-06-21

    We show how graph theory can be combined with quantum theory to calculate the electronic structure of large complex systems. The graph formalism is general and applicable to a broad range of electronic structure methods and materials, including challenging systems such as biomolecules. The methodology combines well-controlled accuracy, low computational cost, and natural low-communication parallelism. This combination addresses substantial shortcomings of linear scaling electronic structure theory, in particular with respect to quantum-based molecular dynamics simulations.

  15. Electronic Biosensors Based on III-Nitride Semiconductors.

    Science.gov (United States)

    Kirste, Ronny; Rohrbaugh, Nathaniel; Bryan, Isaac; Bryan, Zachary; Collazo, Ramon; Ivanisevic, Albena

    2015-01-01

    We review recent advances of AlGaN/GaN high-electron-mobility transistor (HEMT)-based electronic biosensors. We discuss properties and fabrication of III-nitride-based biosensors. Because of their superior biocompatibility and aqueous stability, GaN-based devices are ready to be implemented as next-generation biosensors. We review surface properties, cleaning, and passivation as well as different pathways toward functionalization, and critically analyze III-nitride-based biosensors demonstrated in the literature, including those detecting DNA, bacteria, cancer antibodies, and toxins. We also discuss the high potential of these biosensors for monitoring living cardiac, fibroblast, and nerve cells. Finally, we report on current developments of covalent chemical functionalization of III-nitride devices. Our review concludes with a short outlook on future challenges and projected implementation directions of GaN-based HEMT biosensors.

  16. Efficiency and hardware comparison of analog control-based and digital control-based 70 W two-stage power factor corrector and DC-DC converters

    DEFF Research Database (Denmark)

    Török, Lajos; Munk-Nielsen, Stig

    2011-01-01

    A comparison of an analog and a digital controller driven 70 W two-stage power factor corrector converter is presented. Both controllers are operated in average current-mode-control for the PFC and peak current control for the DC-DC converter. Digital controller design and converter modeling...... is described. Results show that digital control can compete with the analog one in efficiency, PFC and THD....

  17. Communication: Electron ionization of DNA bases

    Energy Technology Data Exchange (ETDEWEB)

    Rahman, M. A.; Krishnakumar, E., E-mail: ekkumar@tifr.res.in

    2016-04-28

    No reliable experimental data exist for the partial and total electron ionization cross sections for DNA bases, which are very crucial for modeling radiation damage in genetic material of living cell. We have measured a complete set of absolute partial electron ionization cross sections up to 500 eV for DNA bases for the first time by using the relative flow technique. These partial cross sections are summed to obtain total ion cross sections for all the four bases and are compared with the existing theoretical calculations and the only set of measured absolute cross sections. Our measurements clearly resolve the existing discrepancy between the theoretical and experimental results, thereby providing for the first time reliable numbers for partial and total ion cross sections for these molecules. The results on fragmentation analysis of adenine supports the theory of its formation in space.

  18. A molecular shift register based on electron transfer

    Science.gov (United States)

    Hopfield, J. J.; Onuchic, Josenelson; Beratan, David N.

    1988-01-01

    An electronic shift-register memory at the molecular level is described. The memory elements are based on a chain of electron-transfer molecules and the information is shifted by photoinduced electron-transfer reactions. This device integrates designed electronic molecules onto a very large scale integrated (silicon microelectronic) substrate, providing an example of a 'molecular electronic device' that could actually be made. The design requirements for such a device and possible synthetic strategies are discussed. Devices along these lines should have lower energy usage and enhanced storage density.

  19. Curriculum and Law: An Elaboration of the Analogy.

    Science.gov (United States)

    Orpwood, Graham W. F.

    A new conceptualization of the curriculum field is offered that is based on an analogy with the field of law. The conceptualization is able to account for the existence in curriculum of a variety of differing normative curriculum theories. Two theories of law (natural law and legal positivism) are described and shown to have exact counterparts in…

  20. Information retrieval system with ability of analogical inference using semantic network and function of fuzzification

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, K; Iwai, S

    1982-01-01

    In information retrieval system, it is necessary to grasp user's subject of interest in order to present appropriate documents to the user. In this paper, the authors propose a model of human ability of analogical inference based on association between key words and, using it, construct an information retrieval system in which the computer with the ability learns its user's subject of interest through question-answering with the user. In this system, the association between key words is represented by a semantic network, and a function of fuzzification of input information is introduced in the semantic network to implement the ability of analogical inference based on the association. Finally, the effect of analogical inference on the learning efficiency of the system is investigated. 5 references.

  1. Electronics all-in-one for dummies

    CERN Document Server

    Lowe, Doug

    2011-01-01

    Take your electronics skills to the next level! If you're looking for a solitary resource that covers everything you need to know about electronics, then look no further. This friendly-and-straightforward guide introduces the basics of electronics and enhances your learning experience by debunking and explaining concepts such as circuits, analog and digital, schematics, voltage, safety concerns, and more. Packed with nearly 900 pages of detailed information, this book shows you how to develop your own breadboard, design your own circuit, and get savvy with schematics. Cover

  2. Enhanced efficacy (intrinsic activity) of cyclic opioid peptide analogs at the μ-receptor

    International Nuclear Information System (INIS)

    Schiller, P.W.; Lemieux, C.; Nguyen, T.M.D.; Maziak, L.A.

    1986-01-01

    Side-chain to end group cyclized enkephalin analogs (e.g. H-Tyr-cyclo[-D-Lys-Gly-Phe-Leu-] and cyclic opioid peptide analogs obtained through covalent linkage of two side-chains (e.g. H-Tyr-D-Cys-Gly-Phe-Cys-NH 2 or H-Tyr-D-Lys-Gly-Phe-Glu-NH 3 ) were tested in the μ-receptor-representative guinea pig ileum (GPI) bioassay and in a binding assay based on displacement of the μ-ligand [ 3 H]DAGO from rat brain membranes. The cyclic analogs were 5 to 70 times more potent in the GPI assay than in the binding assay, whereas linear analogs showed equal potency in the two assays. These results suggest that the efficacy (intrinsic activity) of cyclic opioid peptide analogs at the μ-receptor is increased as a consequence of the conformation constraint imposed through ring closure. This effect was most pronounced in analogs containing a long hydrophobic sidechain as part of the ring structure in the 2-position of the peptide sequence. Further experimental evidence ruled out the possibilities that these potency discrepancies may be due to differences in enzymatic degradation, dissimilar exposure of the receptors in their lipid environment or interaction with different receptor types in the two assay systems. It can be hypothesized that the semi-rigid cyclic analogs may induce a more productive conformational change in the receptor protein than the linear peptides

  3. Analogical reasoning and the nature of context: a research note.

    Science.gov (United States)

    Richardson, K; Webster, D S

    1996-03-01

    Recent theorising about children's reasoning has tended to move towards a 'contextualist' view of cognition and away from the idea of an overall, context-free, mechanism, varying in efficiency, which is the presupposition underlying traditional standardised reasoning tests. An earlier study suggesting improved reasoning performance among children on socio-cognitively meaningful versions of Raven's Matrices tended to support this shift. The main purpose of the study reported here was to observe whether a similar improvement would be found with contextually-based analogical reasoning problems as well. Ten analogy items from a standardised test were administered to 11-year-olds together with 10 structurally-equivalent knowledge-based items. The results reflected improved performance on the latter, overall, and additional analyses led to further suggestions about the nature of the 'contextual advantage' and the origins of item difficulty.

  4. Performance of the front-end signal processing electronics for the drift chambers of the Stanford Large Detector

    International Nuclear Information System (INIS)

    Honma, A.; Haller, G.M.; Usher, T.; Shypit, R.

    1990-10-01

    This paper reports on the performance of the front-end analog and digital signal processing electronics for the drift chambers of the Stanford Large Detector (SLD) detector at the Stanford Linear Collider. The electronics mounted on printed circuit boards include up to 64 channels of transimpedance amplification, analog sampling, A/D conversion, and associated control circuitry. Measurements of the time resolution, gain, noise, linearity, crosstalk, and stability of the readout electronics are described and presented. The expected contribution of the electronics to the relevant drift chamber measurement resolutions (i.e., timing and charge division) is given

  5. Quinoline-Flanked Diketopyrrolopyrrole Copolymers Breaking through Electron Mobility over 6 cm2 V-1 s-1 in Flexible Thin Film Devices.

    Science.gov (United States)

    Ni, Zhenjie; Dong, Huanli; Wang, Hanlin; Ding, Shang; Zou, Ye; Zhao, Qiang; Zhen, Yonggang; Liu, Feng; Jiang, Lang; Hu, Wenping

    2018-03-01

    Herein, the design and synthesis of novel π-extended quinoline-flanked diketopyrrolopyrrole (DPP) [abbreviated as QDPP] motifs and corresponding copolymers named PQDPP-T and PQDPP-2FT for high performing n-type organic field-effect transistors (OFETs) in flexible organic thin film devices are reported. Serving as DPP-flankers in backbones, quinoline is found to effectively tune copolymer optoelectric properties. Compared with TDPP and pyridine-flanked DPP (PyDPP) analogs, widened bandgaps and strengthened electron deficiency are achieved. Moreover, both hole and electron mobility are improved two orders of magnitude compared to those of PyDPP analogs (PPyDPP-T and PPyDPP-2FT). Notably, featuring an all-acceptor-incorporated backbone, PQDPP-2FT exhibits electron mobility of 6.04 cm 2 V -1 s -1 , among the highest value in OFETs fabricated on flexible substrates to date. Moreover, due to the widened bandgap and strengthened electron deficiency of PQDPP, n-channel on/off ratio over 10 5 with suppressed hole transport is first realized in the ambipolar DPP-based copolymers. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Analog front-end cell designed in a commercial 025 mu m process for the ATLAS pixel detector at LHC

    CERN Document Server

    Blanquart, L; Comes, G; Denes, P; Einsweiler, Kevin F; Fischer, P; Mandelli, E; Meddeler, G; Peric, I; Richardson, J

    2002-01-01

    A new analog pixel front-end cell has been developed for the ATLAS detector at the future Large Hadron Collider (LHC) at the European Laboratory for Particle Physics (CERN). This analog cell has been submitted in two commercial 0.25 mu m CMOS processes (in an analog test chip format), using special layout techniques for radiation hardness purposes. It is composed of two cascaded amplifiers followed by a fast discriminator featuring a detection threshold within the range of 1000 to 10000 electrons. The first preamplifier has the principal role of providing a large bandwidth, low input impedance, and fast rise time in order to enhance the time-walk and crosstalk performance, whereas the second fully differential amplifier is aimed at delivering a sufficiently high-voltage gain for optimum comparison. A new do feedback concept renders the cell tolerant of sensor leakage current up to 300 nA and provides monitoring of this current. Two 5-bit digital-to-analog converters tolerant to single- event upset have been i...

  7. Readout electronics development for the ATLAS silicon tracker

    International Nuclear Information System (INIS)

    Borer, K.; Beringer, J.; Anghinolfi, F.; Aspell, P.; Chilingarov, A.; Jarron, P.; Heijne, E.H.M.; Santiard, J.C.; Verweij, H.; Goessling, C.; Lisowski, B.; Reichold, A.; Bonino, R.; Clark, A.G.; Kambara, H.; La Marra, D.; Leger, A.; Wu, X.; Richeux, J.P.; Taylor, G.N.; Fedotov, M.; Kuper, E.; Velikzhanin, Yu.; Campbell, D.; Murray, P.; Seller, P.

    1995-01-01

    We present the status of the development of the readout electronics for the large area silicon tracker of the ATLAS experiment at the LHC, carried out by the CERN RD2 project. Our basic readout concept is to integrate a fast amplifier, analog memory, sparse data scan circuit and analog-to-digital convertor (ADC) on a single VLSI chip. This architecture will provide full analog information of charged particle hits associated unambiguously to one LHC beam crossing, which is expected to be at a frequency of 40 MHz. The expected low occupancy of the ATLAS inner silicon detectors allows us to use a low speed (5 MHz) on-chip ADC with a multiplexing scheme. The functionality of the fast amplifier and analog memory have been demonstrated with various prototype chips. Most recently we have successfully tested improved versions of the amplifier and the analog memory. A piecewise linear ADC has been fabricated and performed satisfactorily up to 5 MHz. A new chip including amplifier, analog memory, memory controller, ADC, and data buffer has been designed and submitted for fabrication and will be tested on a prototype of the ATLAS silicon tracker module with realistic electrical and mechanical constraints. (orig.)

  8. The Phase-I Trigger Readout Electronics Upgrade of the ATLAS Liquid Argon Calorimeters

    CERN Document Server

    Yang, Yi-lin; The ATLAS collaboration

    2018-01-01

    The Super Cell has been proposed in the Phase-I LAr upgrade to replace the existing trigger system "Trigger Tower" due to higher luminosity environments in Run 3 at LHC. The higher granularity of the Super Cell trigger systems requires higher data transmission and processing rate. The new system is also needed to be compatible with the existing trigger system. To fulfill these requirements, the new electronics including frond end and back end are developed. In the front-end part, the new LSB sums the LAr cell signals into Super Cell signals. The new baseplane distributes analog signals among FEBs, LTDB and TBB. The LTDB sums Super Cell signals to Trigger Tower signals and redirected the signals to TBB. The Analog signals are also digitized in LTDB and then sent to back end electronics. In the back-end part, the architecture is based on ATCA. The LAr carrier is used for monitoring and controlling. The LATOMEs inserted into the LAr carrier provide energy calculation from the digitized signals. So far, the demon...

  9. Electron capture detector based on a non-radioactive electron source: operating parameters vs. analytical performance

    Directory of Open Access Journals (Sweden)

    E. Bunert

    2017-12-01

    Full Text Available Gas chromatographs with electron capture detectors are widely used for the analysis of electron affine substances such as pesticides or chlorofluorocarbons. With detection limits in the low pptv range, electron capture detectors are the most sensitive detectors available for such compounds. Based on their operating principle, they require free electrons at atmospheric pressure, which are usually generated by a β− decay. However, the use of radioactive materials leads to regulatory restrictions regarding purchase, operation, and disposal. Here, we present a novel electron capture detector based on a non-radioactive electron source that shows similar detection limits compared to radioactive detectors but that is not subject to these limitations and offers further advantages such as adjustable electron densities and energies. In this work we show first experimental results using 1,1,2-trichloroethane and sevoflurane, and investigate the effect of several operating parameters on the analytical performance of this new non-radioactive electron capture detector (ECD.

  10. Analogical Matrices in Young Children and Students with Intellectual Disability: Reasoning by Analogy or Reasoning by Association?

    Science.gov (United States)

    Denaes, Caroline

    2012-01-01

    Background: Analogical reasoning (AR) is renowned for being a complex activity. Young children tend to reason by association, rather by analogy, and people with intellectual disability present problems of memorization. Both these populations usually show low performances in AR. The present author investigated whether familiar material and external…

  11. Neurotoxic Alkaloids: Saxitoxin and Its Analogs

    Directory of Open Access Journals (Sweden)

    Troco K. Mihali

    2010-07-01

    Full Text Available Saxitoxin (STX and its 57 analogs are a broad group of natural neurotoxic alkaloids, commonly known as the paralytic shellfish toxins (PSTs. PSTs are the causative agents of paralytic shellfish poisoning (PSP and are mostly associated with marine dinoflagellates (eukaryotes and freshwater cyanobacteria (prokaryotes, which form extensive blooms around the world. PST producing dinoflagellates belong to the genera Alexandrium, Gymnodinium and Pyrodinium whilst production has been identified in several cyanobacterial genera including Anabaena, Cylindrospermopsis, Aphanizomenon Planktothrix and Lyngbya. STX and its analogs can be structurally classified into several classes such as non-sulfated, mono-sulfated, di-sulfated, decarbamoylated and the recently discovered hydrophobic analogs—each with varying levels of toxicity. Biotransformation of the PSTs into other PST analogs has been identified within marine invertebrates, humans and bacteria. An improved understanding of PST transformation into less toxic analogs and degradation, both chemically or enzymatically, will be important for the development of methods for the detoxification of contaminated water supplies and of shellfish destined for consumption. Some PSTs also have demonstrated pharmaceutical potential as a long-term anesthetic in the treatment of anal fissures and for chronic tension-type headache. The recent elucidation of the saxitoxin biosynthetic gene cluster in cyanobacteria and the identification of new PST analogs will present opportunities to further explore the pharmaceutical potential of these intriguing alkaloids.

  12. Relating derived relations as a model of analogical reasoning: reaction times and event-related potentials.

    Science.gov (United States)

    Barnes-Holmes, Dermot; Regan, Donal; Barnes-Holmes, Yvonne; Commins, Sean; Walsh, Derek; Stewart, Ian; Smeets, Paul M; Whelan, Robert; Dymond, Simon

    2005-11-01

    The current study aimed to test a Relational Frame Theory (RFT) model of analogical reasoning based on the relating of derived same and derived difference relations. Experiment 1 recorded reaction time measures of similar-similar (e.g., "apple is to orange as dog is to cat") versus different-different (e.g., "he is to his brother as chalk is to cheese") derived relational responding, in both speed-contingent and speed-noncontingent conditions. Experiment 2 examined the event-related potentials (ERPs) associated with these two response patterns. Both experiments showed similar-similar responding to be significantly faster than different-different responding. Experiment 2 revealed significant differences between the waveforms of the two response patterns in the left-hemispheric prefrontal regions; different-different waveforms were significantly more negative than similar-similar waveforms. The behavioral and neurophysiological data support the RFT prediction that, all things being equal, similar-similar responding is relationally "simpler" than, and functionally distinct from, different-different analogical responding. The ERP data were fully consistent with findings in the neurocognitive literature on analogy. These findings strengthen the validity of the RFT model of analogical reasoning and supplement the behavior-analytic approach to analogy based on the relating of derived relations.

  13. The use of UV, FT-IR and Raman spectra for the identification of the newest penem analogs: solutions based on mathematic procedure and the density functional theory.

    Science.gov (United States)

    Cielecka-Piontek, J; Lewandowska, K; Barszcz, B; Paczkowska, M

    2013-02-15

    The application of ultraviolet, FT-IR and Raman spectra was proposed for identification studies of the newest penem analogs (doripenem, biapenem and faropenem). An identification of the newest penem analogs based on their separation from related substances was achieved after the application of first derivative of direct spectra in ultraviolet which permitted elimination of overlapping effects. A combination of experimental and theoretical studies was performed for analyzing the structure and vibrational spectra (FT-IR and Raman spectra) of doripenem, biapenem and faropenem. The calculations were conducted using the density functional theory with the B3LYP hybrid functional and 6-31G(d,p) basis set. The confirmation of the applicability of the DFT methodology for interpretation of vibrational IR and Raman spectra of the newest penem analogs contributed to determination of changes of vibrations in the area of the most labile bonds. By employing the theoretical approach it was possible to eliminate necessity of using reference standards which - considering the instability of penem analogs - require that correction coefficients are factored in. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. Thermoelectricity analogy method for computing the periodic heat transfer in external building envelopes

    International Nuclear Information System (INIS)

    Peng Changhai; Wu Zhishen

    2008-01-01

    Simple and effective computation methods are needed to calculate energy efficiency in buildings for building thermal comfort and HVAC system simulations. This paper, which is based upon the theory of thermoelectricity analogy, develops a new harmonic method, the thermoelectricity analogy method (TEAM), to compute the periodic heat transfer in external building envelopes (EBE). It presents, in detail, the principles and specific techniques of TEAM to calculate both the decay rates and time lags of EBE. First, a set of linear equations is established using the theory of thermoelectricity analogy. Second, the temperature of each node is calculated by solving the linear equations set. Finally, decay rates and time lags are found by solving simple mathematical expressions. Comparisons show that this method is highly accurate and efficient. Moreover, relative to the existing harmonic methods, which are based on the classical control theory and the method of separation of variables, TEAM does not require complicated derivation and is amenable to hand computation and programming

  15. Molecular interactions between (--epigallocatechin gallate analogs and pancreatic lipase.

    Directory of Open Access Journals (Sweden)

    Shihui Wang

    Full Text Available The molecular interactions between pancreatic lipase (PL and four tea polyphenols (EGCG analogs, like (--epigallocatechin gallate (EGCG, (--gallocatechin gallate (GCG, (--epicatechin gallate (ECG, and (--epigallocatechin (EC, were studied from PL activity, conformation, kinetics and thermodynamics. It was observed that EGCG analogs inhibited PL activity, and their inhibitory rates decreased by the order of EGCG>GCG>ECG>EC. PL activity at first decreased rapidly and then slowly with the increase of EGCG analogs concentrations. α-Helix content of PL secondary structure decreased dependent on EGCG analogs concentration by the order of EGCG>GCG>ECG>EC. EGCG, ECG, and EC could quench PL fluorescence both dynamically and statically, while GCG only quenched statically. EGCG analogs would induce PL self-assembly into complexes and the hydrodynamic radii of the complexes possessed a close relationship with the inhibitory rates. Kinetics analysis showed that EGCG analogs non-competitively inhibited PL activity and did not bind to PL catalytic site. DSC measurement revealed that EGCG analogs decreased the transition midpoint temperature of PL enzyme, suggesting that these compounds reduced PL enzyme thermostability. In vitro renaturation through urea solution indicated that interactions between PL and EGCG analogs were weak and non-covalent.

  16. Functional DNA: Teaching Infinite Series through Genetic Analogy

    Science.gov (United States)

    Kowalski, R. Travis

    2011-01-01

    This article presents an extended analogy that connects infinite sequences and series to the science of genetics, by identifying power series as "DNA for a function." This analogy allows standard topics such as convergence tests or Taylor approximations to be recast in a "forensic" light as mathematical analogs of genetic concepts such as DNA…

  17. Analogy between soap film and gas dynamics. I. Equations and shock jump conditions

    Energy Technology Data Exchange (ETDEWEB)

    Wen, C.Y.; Lai, J.Y. [Department of Mechanical Engineering, Da-Yeh University, Chang-Hwa (Taiwan)

    2003-01-01

    The governing equations of compressible flows in soap films are formulated based on the very specific property equations of soap films. The basic normal shock relations and the Rankine-Hugoniot equation are derived for steady one-dimensional flows in soap films. The results are similar to those of compressible gases. The analogy between compressible flows in soap films and that in gases is discussed. On short time scales, the dynamic response of the film is characterized by the Marangoni elasticity, and soap films are shown to be analogous to compressible gases with a specific heat ratio of {gamma}=1.0. Results for Gibbs elasticity are also presented for reference, and no clear analogy to compressible gases is obtained. (orig.)

  18. Effect of MeV Electron Radiation on Europa’s Surface Ice Analogs

    Science.gov (United States)

    Gudipati, Murthy; Henderson, Bryana; Bateman, Fred

    2017-10-01

    MeV electrons that impact Europa’s trailing hemisphere and cause both physical and chemical alteration of the surface and near-surface. The trailing hemisphere receives far lower fluxes above 25 MeV as compared with lower energy particles, but can cause significant chemical and physical modifications at these energies. With NASA's planned Europa Clipper mission and a Europa Lander Concept on the horizon, it is critical to understand and quantify the effect of Europa’s radiation environment on the surface and near surface.Electrons penetrate through ice by far the deepest at any given energy compared to protons and ions, making the role of electrons very important to understand. In addition, secondary radiation - Bremsstrahlung, in X-ray wavelengths - is generated during high-energy particle penetration through solids. Secondary X-rays are equally lethal to life and penetrate even deeper than electrons, making the cumulative effect of radiation on damaging organic matter on the near surface of Europa a complex process that could have effects several meters below Europa’s surface. Other physical properties such as coloration could be caused by radiation.In order to quantify this effect under realistic Europa trailing hemisphere conditions, we devised, built, tested, and obtained preliminary results using our ICE-HEART instrument prototype totally funded by JPL’s internal competition funding for Research and Technology Development. Our Ice Chamber for Europa High-Energy Electron And Radiation-Environment Testing (ICE-HEART) operates at ~100 K. We have also implemented a magnet that is used to remove primary electrons subsequent to passing through an ice column, in order to determine the flux of secondary X-radiation and its penetration through ice.Some of the first results from these studies will be presented and their relevance to understand physical and chemical properties of Europa’s trailing hemisphere surface.This work has been carried out at Jet

  19. DockoMatic: automated peptide analog creation for high throughput virtual screening.

    Science.gov (United States)

    Jacob, Reed B; Bullock, Casey W; Andersen, Tim; McDougal, Owen M

    2011-10-01

    The purpose of this manuscript is threefold: (1) to describe an update to DockoMatic that allows the user to generate cyclic peptide analog structure files based on protein database (pdb) files, (2) to test the accuracy of the peptide analog structure generation utility, and (3) to evaluate the high throughput capacity of DockoMatic. The DockoMatic graphical user interface interfaces with the software program Treepack to create user defined peptide analogs. To validate this approach, DockoMatic produced cyclic peptide analogs were tested for three-dimensional structure consistency and binding affinity against four experimentally determined peptide structure files available in the Research Collaboratory for Structural Bioinformatics database. The peptides used to evaluate this new functionality were alpha-conotoxins ImI, PnIA, and their published analogs. Peptide analogs were generated by DockoMatic and tested for their ability to bind to X-ray crystal structure models of the acetylcholine binding protein originating from Aplysia californica. The results, consisting of more than 300 simulations, demonstrate that DockoMatic predicts the binding energy of peptide structures to within 3.5 kcal mol(-1), and the orientation of bound ligand compares to within 1.8 Å root mean square deviation for ligand structures as compared to experimental data. Evaluation of high throughput virtual screening capacity demonstrated that Dockomatic can collect, evaluate, and summarize the output of 10,000 AutoDock jobs in less than 2 hours of computational time, while 100,000 jobs requires approximately 15 hours and 1,000,000 jobs is estimated to take up to a week. Copyright © 2011 Wiley Periodicals, Inc.

  20. Analog techniques in CEBAF's RF control system

    International Nuclear Information System (INIS)

    Hovater, C.; Fugitt, J.

    1989-01-01

    Recent developments in high-speed analog technology have progressed into the areas of traditional RF technology. Diode related devices are being replaced by analog IC's in the CEBAF RF control system. Complex phase modulators and attenuators have been successfully tested at 70 MHz. They have three advantages over existing technology: lower cost, less temperature sensitivity, and more linearity. RF signal conditioning components and how to implement the new analog IC's will be covered in this paper. 4 refs., 5 figs

  1. Analog techniques in CEBAF'S RF control system

    International Nuclear Information System (INIS)

    Hovater, C.; Fugitt, J.

    1989-01-01

    Recent developments in high-speed analog technology have progressed into the areas of traditional rf technology. Diode-related devices are being replaced by analog IC's in the CEBAF rf control system. Complex phase modulators and attenuators have been successfully tested at 70 MHz. They have three advantages over existing technology: lower cost, less temperature sensitivity, and more linearity. Rf signal conditioning components and how to implement the new analog IC's will be covered in this paper. 4 refs., 5 figs

  2. A glossary of electronics and microelectronics

    International Nuclear Information System (INIS)

    Sautter, D.; Weinerth, H.

    1990-01-01

    The glossary presents terms, definitions and full-text explanations of terminology used in the following subject fields: semiconductor technology, integrated analog and digital semiconductor devices and group of devices, discrete devices including power semiconductors, electronic tubes, electronic display or read-out systems (cathode-ray tubes, liquid crystals, luminescence diodes, plasma- and magneto-optical display devices), sensors, opto-electronics (lasers, integrated optical systems, glass fibre technology, opto-electronic switches), design and circuitry, electromechanical devices; and also terminology from the fields of: solid state physics, acoustics, technical reliability, measuring and testing, entertainment electronics, electrical and magnetic materials, electronic image recording and image processing. There are over 2000 terms and corresponding explanations in the glossary, supplemented by numerous functional diagrams, tables, and figures. (orig./HP) [de

  3. Dual-mode operation of 2D material-base hot electron transistors.

    Science.gov (United States)

    Lan, Yann-Wen; Torres, Carlos M; Zhu, Xiaodan; Qasem, Hussam; Adleman, James R; Lerner, Mitchell B; Tsai, Shin-Hung; Shi, Yumeng; Li, Lain-Jong; Yeh, Wen-Kuan; Wang, Kang L

    2016-09-01

    Vertical hot electron transistors incorporating atomically-thin 2D materials, such as graphene or MoS2, in the base region have been proposed and demonstrated in the development of electronic and optoelectronic applications. To the best of our knowledge, all previous 2D material-base hot electron transistors only considered applying a positive collector-base potential (VCB > 0) as is necessary for the typical unipolar hot-electron transistor behavior. Here we demonstrate a novel functionality, specifically a dual-mode operation, in our 2D material-base hot electron transistors (e.g. with either graphene or MoS2 in the base region) with the application of a negative collector-base potential (VCB transistors can operate in either a hot-electron or a reverse-current dominating mode depending upon the particular polarity of VCB. Furthermore, these devices operate at room temperature and their current gains can be dynamically tuned by varying VCB. We anticipate our multi-functional dual-mode transistors will pave the way towards the realization of novel flexible 2D material-based high-density and low-energy hot-carrier electronic applications.

  4. Progress on the development of a detector mounted analog and digital readout system for the ATLAS TRT

    CERN Document Server

    Baxter, C; Dressnandt, N; Gay, C; Lundberg, B; Munar, A; Mayers, G; Newcomer, M; Van Berg, R; Williams, H H

    2004-01-01

    The 430,000 element ATLAS Transition Radiation straw tube Tracker (TRT) is divided into a central barrel tracker consisting of 104,000 axially mounted straws and two radially arranged end caps on either side of the barrel with 160,000 straws each. To achieve a track position resolution of 140 mu m, the front end electronics must operate at a low (2fC) threshold with a time marking capability of ~1ns. Two ASICs, the ASDBLR and DTMROC provide the complete pipelined readout chain. Custom designed FBGA packages for the ASICs provide a small enough outline to be detector mounted and the extensive use of low level differential signals make mounting the analog packages on printed circuit boards directly opposite the 40 MHz digital chips feasible. The readout electronics for the barrel occupies a potentially important part of the active tracker volume and an aggressive effort has been made to make it as compact as possible. Utilizing a single board for both analog and digital ASICS a 0.1 cm /sup 3/ per channel volume...

  5. Interactions of p-Nitrobenzene Diazonium Fluoroborate and Analogs with the Active Sites of Acetylcholine-Receptor and -Esterase*

    Science.gov (United States)

    Mautner, Henry G.; Bartels, Eva

    1970-01-01

    p-Nitrobenzene diazonium fluoroborate (NDF) is a potent inhibitor of the carbamylcholine-induced depolarization of the electroplax and of acetylcholinesterase. It probably forms covalent bonds with the acetylcholine-receptor and -esterase at the active site of the proteins. Its inhibitory strength is at least the same as that of trimethylammonium diazonium fluoroborate (TDF). The p-acetoxy analog, with its weaker electron-withdrawing group, is about ten times weaker as an inhibitor than the trimethylammonium or p-nitro analogs, both of which have strong electron-withdrawing groups. After treatment of the electroplax preparation with dithiothreitol, NDF remains an irreversible receptor-inhibitor, while TDF becomes a potent reversible receptor-activator. TDF is self-inhibitory: applied before reduction, it no longer depolarizes. Although the first observations on TDF suggested that the compound labels both proteins by virtue of the steric complementary of its trimethylammonium group to a negative subsite in the proteins, the present study indicates that it is the positively charged diazonium group that reacts with the active sites of the proteins to form a covalent bond with an appropriate amino-acid residue. PMID:5272331

  6. Stretchable, Twisted Conductive Microtubules for Wearable Computing, Robotics, Electronics, and Healthcare

    OpenAIRE

    Thanh Nho Do; Yon Visell

    2017-01-01

    Stretchable and flexible multifunctional electronic components, including sensors and actuators, have received increasing attention in robotics, electronics, wearable, and healthcare applications. Despite advances, it has remained challenging to design analogs of many electronic components to be highly stretchable, to be efficient to fabricate, and to provide control over electronic performance. Here, we describe highly elastic sensors and interconnects formed from thin, twisted conductive mi...

  7. Benefit of Analog, Programmable and Digital Hearing Aids

    Directory of Open Access Journals (Sweden)

    Jamileh Fatahi

    2006-12-01

    Full Text Available Background and Aims: As the hearing aid technology progressively promotes toward replacing analog hearing aids with digital and programmable ones, comparison of the patient satisfaction of those kinds of hearing aids by means of a valuable tool seems so necessary. So, the aim of this study was to compare self-reported benefit of analog, digitally controlled programmable and digital hearing aids for reducing disability caused by hearing impairment in mild to severe sensorineural hearing impaired persons. Materials and Methods: This cross-sectional study was performed on 90 persons with mild to severe sensorineural hearing loss dividing into three groups: 43 subjects were fitted with digital, 15 with programmable, 32 with analog hearing aids. After pure tone audiometry, Abbreviated profile of hearing aid benefit (APHAB was completed before and one month after using hearing aids to determine the benefit of them. Results: Global APHAB mean scores for digital, programmable and analog hearing aids were 49.05, 33.19 and 39.53, respectively. Ease of Communication subscale mean scores were 53.46 for digitals, 37.66 for programmables and 39.09 for analogs. Background noise subscale mean scores for digital programmable and analog hearing aids were 46.36, 25.53 and 35.31, respectively. Global and also both subscale mean scores showed significant difference between digital hearing aids and programmable and analog ones. There was no significant difference between reverberation subscale mean scores of three groups. Conclusion: It seems digital hearing aids may be more beneficial to reduce disability caused by hearing loss than analog and programmable hearing aids are.

  8. ANALOGICAL REASONING USING TRANSFORMATIONS OF RULES

    OpenAIRE

    Haraguchi, Makoto; 原口, 誠

    1986-01-01

    A formalism of analogical reasoning is presented. The analogical reasoning can be considered as a deduction with a function of transforming logical rules. From this viewpoint, the reasoning is defined in terms of deduction, and is therefore realized in a logic programming system. The reasoning system is described as an extension of Prolog interpreter.

  9. Digitally controlled analog proportional-integral-derivative (PID) controller for high-speed scanning probe microscopy

    Science.gov (United States)

    Dukic, Maja; Todorov, Vencislav; Andany, Santiago; Nievergelt, Adrian P.; Yang, Chen; Hosseini, Nahid; Fantner, Georg E.

    2017-12-01

    Nearly all scanning probe microscopes (SPMs) contain a feedback controller, which is used to move the scanner in the direction of the z-axis in order to maintain a constant setpoint based on the tip-sample interaction. The most frequently used feedback controller in SPMs is the proportional-integral (PI) controller. The bandwidth of the PI controller presents one of the speed limiting factors in high-speed SPMs, where higher bandwidths enable faster scanning speeds and higher imaging resolution. Most SPM systems use digital signal processor-based PI feedback controllers, which require analog-to-digital and digital-to-analog converters. These converters introduce additional feedback delays which limit the achievable imaging speed and resolution. In this paper, we present a digitally controlled analog proportional-integral-derivative (PID) controller. The controller implementation allows tunability of the PID gains over a large amplification and frequency range, while also providing precise control of the system and reproducibility of the gain parameters. By using the analog PID controller, we were able to perform successful atomic force microscopy imaging of a standard silicon calibration grating at line rates up to several kHz.

  10. Several cases of electronics and the measuring methods

    International Nuclear Information System (INIS)

    Supardiyono, Bb.; Kamadi, J.; Suparmono, M.; Indarto.

    1980-01-01

    Several cases of electronics and the measuring methods, covering electric conductivity and electric potential of analog systems, electric current, electric conductivity and electric potential of semiconductor diodes, and characteristics of transistors are described. (SMN)

  11. The baby and the bath water: improving metaphors and analogies in high school biology texts

    Science.gov (United States)

    Shors, Luke

    This dissertation is concerned with understanding how metaphors and analogies function in biology education and whether some of the philosophical critiques of the language used in the field of biology -- and in particular its accompanying metaphors and analogies, have a basis in the educational materials used to teach the subject. This inquiry was carried out through examining the pedagogical features and content of metaphors and analogies from three high school biology textbooks. After identifying over two hundred and twenty-five verbal and pictorial metaphors and analogies, these figures of speech were coded based on prior research that establishes effective characteristics for their use. In tandem with this quantitative analysis, a philosophical analysis considers how well the content of these metaphors and analogies aligns with current scientific understanding and what misunderstandings may be engendered through the use of these metaphors and analogies. The major findings of the analysis include: 1) Textbook authors are much more likely to utilize metaphors and analogies as well as signal their presence to students compared with past analyses; 2) A number of metaphors and analogies either contain errors in analogical mapping or use source analogues that are too antiquated to support today's students; 3) The content of many metaphors and analogies is frequently outdated in reference to current scientific understanding; and 4) Many metaphors and analogies tend to reinforce tacit elements of past scientific paradigms - these are termed 'reinforcing metaphors' in the dissertation and include nature as machine, nature as blueprint or information, nature as business and nature as war. The present work submits several implications for students learning biology as well as the manner in which students come to understand the natural world. The work suggests ways to reduce ineffective metaphors and analogies as well as reliance on reinforcing metaphors. It offers new

  12. Automatic analog IC sizing and optimization constrained with PVT corners and layout effects

    CERN Document Server

    Lourenço, Nuno; Horta, Nuno

    2017-01-01

    This book introduces readers to a variety of tools for automatic analog integrated circuit (IC) sizing and optimization. The authors provide a historical perspective on the early methods proposed to tackle automatic analog circuit sizing, with emphasis on the methodologies to size and optimize the circuit, and on the methodologies to estimate the circuit’s performance. The discussion also includes robust circuit design and optimization and the most recent advances in layout-aware analog sizing approaches. The authors describe a methodology for an automatic flow for analog IC design, including details of the inputs and interfaces, multi-objective optimization techniques, and the enhancements made in the base implementation by using machine leaning techniques. The Gradient model is discussed in detail, along with the methods to include layout effects in the circuit sizing. The concepts and algorithms of all the modules are thoroughly described, enabling readers to reproduce the methodologies, improve the qual...

  13. Mixed Analog/Digital Matrix-Vector Multiplier for Neural Network Synapses

    DEFF Research Database (Denmark)

    Lehmann, Torsten; Bruun, Erik; Dietrich, Casper

    1996-01-01

    In this work we present a hardware efficient matrix-vector multiplier architecture for artificial neural networks with digitally stored synapse strengths. We present a novel technique for manipulating bipolar inputs based on an analog two's complements method and an accurate current rectifier...

  14. Analog Amplitude Modulation of a High Voltage, Solid State Inductive Adder, Pulse Generator Using MOSFETS

    International Nuclear Information System (INIS)

    Gower, E J; Sullivan, J S

    2002-01-01

    High voltage, solid state, inductive adder, pulse generators have found increasing application as fast kicker pulse modulators for charged particle beams. The solid state, inductive adder, pulse generator is similar in operation to the linear induction accelerator. The main difference is that the solid state, adder couples energy by transformer action from multiple primaries to a voltage summing stalk, instead of an electron beam. Ideally, the inductive adder produces a rectangular voltage pulse at the load. In reality, there is usually some voltage variation at the load due to droop on primary circuit storage capacitors, or, temporal variations in the load impedance. Power MOSFET circuits have been developed to provide analog modulation of the output voltage amplitude of a solid state, inductive adder, pulse generator. The modulation is achieved by including MOSFET based, variable subtraction circuits in the multiple primary stack. The subtraction circuits can be used to compensate for voltage droop, or, to tailor the output pulse amplitude to provide a desired effect in the load. Power MOSFET subtraction circuits have been developed to modulate short, temporal (60-400 ns), voltage and current pulses. MOSFET devices have been tested up to 20 amps and 800 Volts with a band pass of 50 MHz. An analog modulation cell has been tested in a five cell high, voltage adder stack

  15. Electronic states of graphene nanoribbons and analytical solutions

    Directory of Open Access Journals (Sweden)

    Katsunori Wakabayashi, Ken-ichi Sasaki, Takeshi Nakanishi and Toshiaki Enoki

    2010-01-01

    Full Text Available Graphene is a one-atom-thick layer of graphite, where low-energy electronic states are described by the massless Dirac fermion. The orientation of the graphene edge determines the energy spectrum of π-electrons. For example, zigzag edges possess localized edge states with energies close to the Fermi level. In this review, we investigate nanoscale effects on the physical properties of graphene nanoribbons and clarify the role of edge boundaries. We also provide analytical solutions for electronic dispersion and the corresponding wavefunction in graphene nanoribbons with their detailed derivation using wave mechanics based on the tight-binding model. The energy band structures of armchair nanoribbons can be obtained by making the transverse wavenumber discrete, in accordance with the edge boundary condition, as in the case of carbon nanotubes. However, zigzag nanoribbons are not analogous to carbon nanotubes, because in zigzag nanoribbons the transverse wavenumber depends not only on the ribbon width but also on the longitudinal wavenumber. The quantization rule of electronic conductance as well as the magnetic instability of edge states due to the electron–electron interaction are briefly discussed.

  16. FPGA-based upgrade of the read-out electronics for the low energy polarimeter at COSY/Juelich

    Energy Technology Data Exchange (ETDEWEB)

    Hempelmann, Nils [Institut fuer Kernphysik, Forschungszentrum Juelich (Germany); Collaboration: JEDI-Collaboration

    2016-07-01

    The Cooler Synchrotron (COSY) is a facility for cooled polarized beams at the Forschungszentrum in Juelich. The Low Energy Polarimeter (LEP) is the polarimeter in the injection beam line of COSY. The beam polarization is measured using scattering off carbon and polyethylene (CH2) targets. The outgoing particles are detected using twelve plastic scintillators installed in groups of three to the left, to the right, above, and below the beam. The LEP is the routine tool for beam set-up, but its performance was limited by the old read-out electronics consisting of analog NIM modules. A new system using analog pulse sampling and an FPGA chip for signal processing was installed and tested. The ejectile particles were identified by relative time of flight measurement using a signal from the RF amplifier of the cyclotron used for acceleration as a reference. The new system is able to measure the time at which a particle arrives to an accuracy in the order of 50 ps. The presentation includes a review of available systems and a report about measurements in May and December 2015.

  17. Memristor-Based Analog Computation and Neural Network Classification with a Dot Product Engine.

    Science.gov (United States)

    Hu, Miao; Graves, Catherine E; Li, Can; Li, Yunning; Ge, Ning; Montgomery, Eric; Davila, Noraica; Jiang, Hao; Williams, R Stanley; Yang, J Joshua; Xia, Qiangfei; Strachan, John Paul

    2018-03-01

    Using memristor crossbar arrays to accelerate computations is a promising approach to efficiently implement algorithms in deep neural networks. Early demonstrations, however, are limited to simulations or small-scale problems primarily due to materials and device challenges that limit the size of the memristor crossbar arrays that can be reliably programmed to stable and analog values, which is the focus of the current work. High-precision analog tuning and control of memristor cells across a 128 × 64 array is demonstrated, and the resulting vector matrix multiplication (VMM) computing precision is evaluated. Single-layer neural network inference is performed in these arrays, and the performance compared to a digital approach is assessed. Memristor computing system used here reaches a VMM accuracy equivalent of 6 bits, and an 89.9% recognition accuracy is achieved for the 10k MNIST handwritten digit test set. Forecasts show that with integrated (on chip) and scaled memristors, a computational efficiency greater than 100 trillion operations per second per Watt is possible. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Cyclopentanoid analogs of phosphatidylcholine: susceptibility to phospholipase A2.

    Science.gov (United States)

    Lister, M D; Hancock, A J

    1988-10-01

    Six isomers of dipalmitoylcyclopentanetriol phosphocholine (cyclopentano-lecithin) were tested as potential substrates for phospholipase A2. Since each of these analogs possesses a configuration that mimics a narrow range of conformations of a glycerophospholipid molecule, the analogs were used to assess the enzyme's conformational requirements. Studies showed that all of the analogs containing the phosphocholine at the C-1 (or C-3) position could be hydrolyzed, while only one of the three analogs that contains the polar head group at the C-2 position was susceptible. Kinetic studies, however, revealed that only the all-trans-(1,3/2-1P)-cyclopentano-lecithin gave initial rates of hydrolysis that were measurable by pH-stat. Acyl group specificity of the enzyme towards the all-trans isomer was determined with an analog was acyl groups were distinguishable. The synthesis of this mixed-acid-cyclopentano-PC is described herein. When this analog was enzymatically assayed, results unequivocally showed the enzyme to be specific for C-2 acyl hydrolysis. This specificity, and data showing that the all-trans analog is stereospecifically hydrolyzed, indicate that it is acted on in an analogous manner to dipalmitoylphosphatidylcholine. These studies indicate that although the configuration of the analog is not necessarily a prerequisite for hydrolysis, there does appear to be an optimal spatial orientation for enzymatic activity. The analogy between the susceptibilities of all-trans-(1,3/2-1P)-cyclopentano-lecithin and glycero-lecithin suggests that the conformation of the glycero-lecithin during phospholipase A2-mediated hydrolysis may be best simulated by the all-trans orientation of C-O bonds in the artificial substrate.

  19. A time to voltage converter and analog memory unit for straw tracking detectors

    International Nuclear Information System (INIS)

    Callewaert, L.; Eyckmans, W.; Sansen, W.; Stevens, A.; Van der Spiegel, J.; Van Berg, R.; Williams, H.H.; Yau, T.Y.

    1990-01-01

    In a high precision drift tube or straw tracking system, one measures the time of arrival of the first electron at the anode. While many possible schemes exist, the authors initial judgment was that an analog time measurement would offer both lower power and greater resolution than an equally complex digital system. In addition, they believe that it will be necessary to incorporate all of the system features such as connection to the trigger and DAQ systems in any usable design in order to keep the power, mass and complexity of the final system under control. A low power, sub-nanosecond accuracy, quick recovery, data-driven, multiple sample Time to Voltage Converter suitable for use on high rate straw tracking detectors is described. The described TVC includes virtual storage of analog data in both Level 1 and Level 2 queues and an on board ADC with first order correction for capacitance variations and non-linearities

  20. High-brightness electron guns for linac-based light sources

    International Nuclear Information System (INIS)

    Lewellen, J.W.

    2004-01-01

    Most proposed linac-based light sources, such as single-pass free-electron lasers and energy-recovery-linacs, require very high-brightness electron beams in order to achieve their design performance. These beam requirements must be achieved not on an occasional basis, but rather must be met by every bunch produced by the source over extended periods of time. It is widely assumed that the beam source will be a photocathode electron gun; the selection of accelerator technique (e.g., dc or rf) for the gun is more dependent on the application.The current state of the art of electron beam production is adequate but not ideal for the first generation of linac-based light sources, such as the Linac Coherent Light Source (LCLS) x-ray free-electron laser (X-FEL). For the next generation of linac-based light sources, an order of magnitude reduction in the transverse electron beam emittance is required to significantly reduce the cost of the facility. This is beyond the present state of the art, given the other beam properties that must be maintained. The requirements for current and future linac-based light source beam sources are presented here, along with a review of the present state of the art. A discussion of potential paths towards meeting future needs is presented at the conclusion.