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Sample records for width modulation control

  1. Single event effects in pulse width modulation controllers

    International Nuclear Information System (INIS)

    Penzin, S.H.; Crain, W.R.; Crawford, K.B.; Hansel, S.J.; Kirshman, J.F.; Koga, R.

    1996-01-01

    SEE testing was performed on pulse width modulation (PWM) controllers which are commonly used in switching mode power supply systems. The devices are designed using both Set-Reset (SR) flip-flops and Toggle (T) flip-flops which are vulnerable to single event upset (SEU) in a radiation environment. Depending on the implementation of the different devices the effect can be significant in spaceflight hardware

  2. Scaling behavior of the thermal conductivity of width-modulated nanowires and nanofilms for heat transfer control at the nanoscale.

    Science.gov (United States)

    Zianni, Xanthippi; Jean, Valentin; Termentzidis, Konstantinos; Lacroix, David

    2014-11-21

    We report on scaling behavior of the thermal conductivity of width-modulated nanowires and nanofilms that have been studied with the phonon Monte Carlo technique. It has been found that the reduction of the thermal conductivity scales with the nanostructure transmissivity, a property entirely determined by the modulation geometry, irrespectively of the material choice. Tuning of the thermal conductivity is possible by the nanostructure width-modulation without strict limitations for the modulation profile. In addition, a very significant constriction thermal resistance due to width-discontinuity has been identified, in analogy to the contact thermal resistance between two dissimilar materials. The constriction thermal resistance also scales with the modulated nanostructure transmissivity. Our conclusions are generic indicating that a wide range of materials can be used for the modulated nanostructures. Direct heat flow control can be provided by designing the nanostructure width-modulation.

  3. Voltage control on TEG-inverter system with pulse width modulation

    International Nuclear Information System (INIS)

    Kimura, N.; Kinoshita, H.; Matsuura, K.

    1984-01-01

    An ocean thermoelectric generating system can be expected to supply cheap electric power in future. And it can be used as base power supply or isolated power source in developing areas. The authors propose to apply forced-commutation inverter to thermoelectric energy conversion system and construct an electric power station which can be operated without any other synchronous generator (S-G) and can control ac system as stable as S-G. This paper shows that inverters can control voltage constant, though within a range of 10% load change, by using pulse width modulation (PWM). It also describes the design of the voltage control system covering from 50% to 100% load with combination of PWM and output voltage tap changing of TEG

  4. Pulse width modulation-based temperature tracking for feedback control of a shape memory alloy actuator.

    Science.gov (United States)

    Ayvali, Elif; Desai, Jaydev P

    2014-04-01

    This work presents a temperature-feedback approach to control the radius of curvature of an arc-shaped shape memory alloy (SMA) wire. The nonlinear properties of the SMA such as phase transformation and its dependence on temperature and stress make SMA actuators difficult to control. Tracking a desired trajectory is more challenging than controlling just the position of the SMA actuator since the desired path is continuously changing. Consequently, tracking the desired strain directly or tracking the parameters such as temperature and electrical resistance that are related to strain with a model is a challenging task. Temperature-feedback is an attractive approach when direct measurement of strain is not practical. Pulse width modulation (PWM) is an effective method for SMA actuation and it can be used along with a compensator to control the temperature of the SMA. Using the constitutive model of the SMA, the desired temperature profile can be obtained for a given strain trajectory. A PWM-based nonlinear PID controller with a feed-forward heat transfer model is proposed to use temperature-feedback for tracking a desired temperature trajectory. The proposed controller is used during the heating phase of the SMA actuator. The controller proves to be effective in tracking step-wise and continuous trajectories.

  5. Controlling DC-DC converters by chaos-based pulse width modulation to reduce EMI

    International Nuclear Information System (INIS)

    Li Hong; Zhang Bo; Li Zhong; Halang, Wolfgang A.; Chen Guanrong

    2009-01-01

    In this paper, periodic and chaotic behaviors of DC-DC converters under certain parametric conditions are simulated, experimentally verified, and analyzed. Motivated by the work of J.H.B. Deane and D.C. Hamill in 1996, where chaotic phenomena are useful in suppressing electromagnetic interference (EMI) by adjusting the parameters of the DC-DC converter and making it operate in chaos, a chaos-based pulse width modulation (CPWM) is proposed to distribute the harmonics of the DC-DC converters continuously and evenly over a wide frequency range, thereby reducing the EMI. The output waves and spectral properties of the EMI are simulated and analyzed as the carrier frequency or amplitude changes with regard to different chaotic maps. Simulation and experimental results are given to illustrate the effectiveness of the proposed CPWM, which provides a good example of applying chaos theory in engineering practice.

  6. Application of chaotic pulse width modulation control for suppressing electromagnetic interference in a half-bridge converter

    Directory of Open Access Journals (Sweden)

    Yuhong Song

    2014-08-01

    Full Text Available It was proposed in the former research that chaos control can be used to suppress electromagnetic interference (EMI in DC–DC converters. Analysis on a half-bridge converter is detailed in this study. Here, the practical example of the power supply of personal computers is given to show that, with an external chaotic signal to a pulse width modulation control circuit, the proposed approach can reduce EMI by reducing the amplitudes of power signals such as transformer current and output inductor currents at multiples of fundamental frequency.

  7. Healthy younger and older adults control foot placement to avoid small obstacles during gait primarily by modulating step width

    Directory of Open Access Journals (Sweden)

    Schulz Brian W

    2012-10-01

    Full Text Available Abstract Background Falls are a significant problem in the older population. Most falls occur during gait, which is primarily regulated by foot placement. Variability of foot placement has been associated with falls, but these associations are inconsistent and generally for smooth, level flooring. This study investigates the control of foot placement and the associated gait variability in younger and older men and women (N=7/group, total N=28 while walking at three different speeds (slow, preferred, and fast across a control surface with no obstacles and surfaces with multiple (64 small (10cm long ×13mm high visible and hidden obstacles. Results Minimum obstacle distance between the shoe and nearest obstacle during each footfall was greater on the visible obstacles surface for older subjects because some of them chose to actively avoid obstacles. This obstacle avoidance strategy was implemented primarily by modulating step width and to a lesser extent step length as indicated by linear regressions of step width and length variability on minimum obstacle distance. Mean gait speed, step length, step width, and step time did not significantly differ by subject group, flooring surface, or obstacle avoidance strategy. Conclusions Some healthy older subjects choose to actively avoid small obstacles that do not substantially perturb their gait by modulating step width and, to a lesser extent, step length. It is not clear if this obstacle avoidance strategy is appropriate and beneficial or overcautious and maladaptive, as it results in fewer obstacles encountered at a consequence of a less efficient gait pattern that has been shown to indicate increased fall risk. Further research is needed on the appropriateness of strategy selection when the environmental demands and/or task requirements have multiple possible completion strategies with conflicting objectives (i.e. perceived safety vs. efficiency.

  8. Design and Simulation of Control Technique for Permanent Magnet Synchronous Motor Using Space Vector Pulse Width Modulation

    Science.gov (United States)

    Khan, Mansoor; Yong, Wang; Mustafa, Ehtasham

    2017-07-01

    After the rapid advancement in the field of power electronics devices and drives for last few decades, there are different kinds of Pulse Width Modulation techniques which have been brought to the market. The applications ranging from industrial appliances to military equipment including the home appliances. The vey common application for the PWM is three phase voltage source inverter, which is used to convert DC to AC in the homes to supply the power to the house in case electricity failure, usually named as Un-interrupted Power Supply. In this paper Space Vector Pulse Width Modulation techniques is discussed and analysed under the control technique named as Field Oriented Control. The working and implementation of this technique has been studied by implementing on the three phase bridge inverter. The technique is used to control the Permanente Magnet Synchronous Motor. The drive system is successfully implemented in MATLAB/Simulink using the mathematical equation and algorithm to achieve the satisfactory results. PI type of controller is used to tuned ers of the motothe parametr i.e. torque and current.

  9. A pulse-width modulated, high reliability charge controller for small photovoltaic systems

    Energy Technology Data Exchange (ETDEWEB)

    Gerken, K. [Morningstar Corp., Olney, MD (United States); Welsh, D. [Morningstar Corp., Encinitas, CA (United States)

    1997-02-01

    This report presents the results of a development effort to design, test and begin production of a new class of small photovoltaic (PV) charge controllers. Sandia National Laboratories provided technical support, test data and financial support through a Balance-of-System Development contract. One of the objectives of the development was to increase user confidence in small PV systems by improving the reliability and operating life of the system controllers. Another equally important objective was to improve the economics of small PV systems by extending the battery lifetimes. Using new technology and advanced manufacturing techniques, these objectives were accomplished. Because small stand-alone PV systems account for over one third of all PV modules shipped, the positive impact of improving the reliability and economics of PV systems in this market segment will be felt throughout the industry. The results of verification testing of the new product are also included in this report. The initial design goals and specifications were very aggressive, but the extensive testing demonstrates that all the goals were achieved. Production of the product started in May at a rate of 2,000 units per month. Over 40 Morningstar distributors (5 US and 35 overseas) have taken delivery in the first 2 months of shipments. Initial customer reactions to the new controller have been very favorable.

  10. Pulse width modulation inverter with battery charger

    Science.gov (United States)

    Slicker, James M.

    1985-01-01

    An inverter is connected between a source of DC power and a three-phase AC induction motor, and a microprocessor-based circuit controls the inverter using pulse width modulation techniques. In the disclosed method of pulse width modulation, both edges of each pulse of a carrier pulse train are equally modulated by a time proportional to sin .theta., where .theta. is the angular displacement of the pulse center at the motor stator frequency from a fixed reference point on the carrier waveform. The carrier waveform frequency is a multiple of the motor stator frequency. The modulated pulse train is then applied to each of the motor phase inputs with respective phase shifts of 120.degree. at the stator frequency. Switching control commands for electronic switches in the inverter are stored in a random access memory (RAM) and the locations of the RAM are successively read out in a cyclic manner, each bit of a given RAM location controlling a respective phase input of the motor. The DC power source preferably comprises rechargeable batteries and all but one of the electronic switches in the inverter can be disabled, the remaining electronic switch being part of a "flyback" DC-DC converter circuit for recharging the battery.

  11. CEDM Controller for a Linear Pulse Motor by using Pulse Width Modulation Method in Integral Reactor

    International Nuclear Information System (INIS)

    Lee, Joon-Koo; Keum, Jong-Yong; Park, Heui-Youn

    2007-01-01

    Integral Reactor SMART is under development at KAERI. The design characteristics of SMART are radically different from those employed in currently operating loop type PWR in Korea. The reliability and accuracy of Control Rod Drive Mechanism are very important to the reactor safety and the design of the Plant Protection System. The SMART CEDM designed for fine-step movement consists of a linear pulse motor, reed switch type sensor with top and bottom limit switches which also act as Control Element Assembly(CEA) Position indicator, The linear pulse motor is a four phase synchronous DC electric machine with inner stator and output stator in coolant medium inside a strong housing. The objective of this paper is to introduce and to explain the CEDM controller CEDM Controller is being developed with a new design concept and digital technology to reduce the Operating Error and improve the systems' reliability and availability. And Switched Mode Power Supply is also being developed with digital hardware technology. This paper involves the test details and result

  12. Modified Synchronous Reference Frame Based Shunt Active Power Filter with Fuzzy Logic Control Pulse Width Modulation Inverter

    Directory of Open Access Journals (Sweden)

    Suleiman Musa

    2017-05-01

    Full Text Available Harmonic distortion in power networks has greatly reduced power quality and this affects system stability. In order to mitigate this power quality issue, the shunt active power filter (SAPF has been widely applied and it is proven to be the best solution to current harmonics. This paper evaluates the performance of the modified synchronous reference frame extraction (MSRF algorithm with fuzzy logic controller (FLC based current control pulse width modulation (PWM inverter of three-phase three-wire SAPF to mitigate current harmonics. The proposed FLC is designed with a reduced amount of membership functions (MFs and rules, and thus significantly reduces the computational time and memory size. Modeling and simulations of SAPF are carried out using MATLAB/Simulink R2012a with the power system toolbox under steady-state condition, and this is followed with hardware implementation using a TMS320F28335 digital signal processor (DSP, Specrum Digital Inc., Stafford, TX, USA. The results obtained demonstrate a good and satisfactory response to mitigate the harmonics in the system. The total harmonic distortion (THD for the system has been reduced from 25.60% to 0.92% and 1.41% in the simulation study with and without FLC, respectively. Similarly for the experimental study, the SAPF can compensate for the three-phase load current by reducing THD to 5.07% and 7.4% with and without FLC, respectively.

  13. Experimental demonstration of line-width modulation in plasmonic lithography using a solid immersion lens-based active nano-gap control

    International Nuclear Information System (INIS)

    Lee, Won-Sup; Kim, Taeseob; Choi, Guk-Jong; Lim, Geon; Joe, Hang-Eun; Gang, Myeong-Gu; Min, Byung-Kwon; Park, No-Cheol; Moon, Hyungbae; Kim, Do-Hyung; Park, Young-Pil

    2015-01-01

    Plasmonic lithography has been used in nanofabrication because of its utility beyond the diffraction limit. The resolution of plasmonic lithography depends on the nano-gap between the nanoaperture and the photoresist surface—changing the gap distance can modulate the line-width of the pattern. In this letter, we demonstrate solid-immersion lens based active non-contact plasmonic lithography, applying a range of gap conditions to modulate the line-width of the pattern. Using a solid-immersion lens-based near-field control system, the nano-gap between the exit surface of the nanoaperture and the media can be actively modulated and maintained to within a few nanometers. The line-widths of the recorded patterns using 15- and 5-nm gaps were 47 and 19.5 nm, respectively, which matched closely the calculated full-width at half-maximum. From these results, we conclude that changing the nano-gap within a solid-immersion lens-based plasmonic head results in varying line-width patterns

  14. Electrical system for pulse-width modulated control of a power inverter using phase-shifted carrier signals and related operating methods

    Science.gov (United States)

    Welchko, Brian A [Torrance, CA

    2012-02-14

    Systems and methods are provided for pulse-width modulated control of power inverter using phase-shifted carrier signals. An electrical system comprises an energy source and a motor. The motor has a first set of windings and a second set of windings, which are electrically isolated from each other. An inverter module is coupled between the energy source and the motor and comprises a first set of phase legs coupled to the first set of windings and a second set of phase legs coupled to the second set of windings. A controller is coupled to the inverter module and is configured to achieve a desired power flow between the energy source and the motor by modulating the first set of phase legs using a first carrier signal and modulating the second set of phase legs using a second carrier signal. The second carrier signal is phase-shifted relative to the first carrier signal.

  15. Utility Interfaced Pulse-Width Modulation of Solar Fed Voltage ...

    African Journals Online (AJOL)

    Utility Interfaced Pulse-Width Modulation of Solar Fed Voltage Source Inverter Using Fixed-Band Hysteresis Current Controller Method. ... with the conversion of solar energy into electrical energy; boosting the dc power; inversion of the dc to ac and then synchronization of the inverter output with the utility, and consequently, ...

  16. Pulse-Width-Modulating Driver for Brushless dc Motor

    Science.gov (United States)

    Salomon, Phil M.

    1991-01-01

    High-current pulse-width-modulating driver for brushless dc motor features optical coupling of timing signals from low-current control circuitry to high-current motor-driving circuitry. Provides high electrical isolation of motor-power supply, helping to prevent fast, high-current motor-driving pulses from being coupled through power supplies into control circuitry, where they interfere with low-current control signals.

  17. An adaptive neuro fuzzy inference system controlled space cector pulse width modulation based HVDC light transmission system under AC fault conditions

    Science.gov (United States)

    Ajay Kumar, M.; Srikanth, N. V.

    2014-03-01

    In HVDC Light transmission systems, converter control is one of the major fields of present day research works. In this paper, fuzzy logic controller is utilized for controlling both the converters of the space vector pulse width modulation (SVPWM) based HVDC Light transmission systems. Due to its complexity in the rule base formation, an intelligent controller known as adaptive neuro fuzzy inference system (ANFIS) controller is also introduced in this paper. The proposed ANFIS controller changes the PI gains automatically for different operating conditions. A hybrid learning method which combines and exploits the best features of both the back propagation algorithm and least square estimation method is used to train the 5-layer ANFIS controller. The performance of the proposed ANFIS controller is compared and validated with the fuzzy logic controller and also with the fixed gain conventional PI controller. The simulations are carried out in the MATLAB/SIMULINK environment. The results reveal that the proposed ANFIS controller is reducing power fluctuations at both the converters. It also improves the dynamic performance of the test power system effectively when tested for various ac fault conditions.

  18. Global synchronization of parallel processors using clock pulse width modulation

    Science.gov (United States)

    Chen, Dong; Ellavsky, Matthew R.; Franke, Ross L.; Gara, Alan; Gooding, Thomas M.; Haring, Rudolf A.; Jeanson, Mark J.; Kopcsay, Gerard V.; Liebsch, Thomas A.; Littrell, Daniel; Ohmacht, Martin; Reed, Don D.; Schenck, Brandon E.; Swetz, Richard A.

    2013-04-02

    A circuit generates a global clock signal with a pulse width modification to synchronize processors in a parallel computing system. The circuit may include a hardware module and a clock splitter. The hardware module may generate a clock signal and performs a pulse width modification on the clock signal. The pulse width modification changes a pulse width within a clock period in the clock signal. The clock splitter may distribute the pulse width modified clock signal to a plurality of processors in the parallel computing system.

  19. Development of microheaters for gas sensor with an AT-Mega 8535 temperature controller using a PWM (pulse width modulation) method

    Science.gov (United States)

    Megayanti, Meti; Panatarani, Camellia; Joni, I. Made

    2016-03-01

    Microheater is the main component in gas sensor characterized by their sensitivity, selectivity, and time response of gas sensor which is depend on the microheater temperature stability. A Cu microheater was developed and utilized AT-Mega 8535 controller using a PWM (pulse width modulation) method. This control system is interfaced to the PC to observe the real time temperature response of the microheater. Three initial resistance (R0) variations of microheater were developed in an open loop control system. The power characteristic of designed microheater depends on the specified microheater initial resistance. The smaller R0, the less power required to reach a temperature setting value. The developed microheater was designed to reach a temperature setting value of 250°C having resistance 0.531 Ω for 1.979 Watt and 0.265 Ω for 1.072 Watt respectively. The results of the investigation on the control performances shows microheater-control system achieved operating temperature up to 250°C. The response of the temperature control shows smallest R0 resulted in a high stability with short settling time, short delay time and small ripple for temperature setting values higher than 150°C. The obtained error of microheater temperature with R0 = 0.265 is 8.596 %. It is concluded that the developed microheater can be utilized as a component of a gas sensor.

  20. Development of microheaters for gas sensor with an AT-Mega 8535 temperature controller using a PWM (pulse width modulation) method

    Energy Technology Data Exchange (ETDEWEB)

    Megayanti, Meti; Panatarani, Camellia; Joni, I. Made, E-mail: imadejoni@phys.unpad.ac.id [Instrumentation System and Functional Material Processing Laboratory, Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Padjadjaran Jalan Raya Bandung-Sumedang KM 21, Jatinangor 45363, West Java (Indonesia)

    2016-03-11

    Microheater is the main component in gas sensor characterized by their sensitivity, selectivity, and time response of gas sensor which is depend on the microheater temperature stability. A Cu microheater was developed and utilized AT-Mega 8535 controller using a PWM (pulse width modulation) method. This control system is interfaced to the PC to observe the real time temperature response of the microheater. Three initial resistance (R0) variations of microheater were developed in an open loop control system. The power characteristic of designed microheater depends on the specified microheater initial resistance. The smaller R0, the less power required to reach a temperature setting value. The developed microheater was designed to reach a temperature setting value of 250°C having resistance 0.531 Ω for 1.979 Watt and 0.265 Ω for 1.072 Watt respectively. The results of the investigation on the control performances shows microheater-control system achieved operating temperature up to 250°C. The response of the temperature control shows smallest R0 resulted in a high stability with short settling time, short delay time and small ripple for temperature setting values higher than 150°C. The obtained error of microheater temperature with R0 = 0.265 is 8.596 %. It is concluded that the developed microheater can be utilized as a component of a gas sensor.

  1. A New Selective Harmonic Elimination Pulse- Width and Amplitude Modulation (SHEPWAM) for Drive Applications

    DEFF Research Database (Denmark)

    Ghoreishy, Hoda; Varjani, Ali Yazdian; Mohamadian, Mustafa

    2013-01-01

    Compared to the conventional selective harmonic elimination-pulse width modulation (SHE-PWM), the selective harmonic elimination-pulse width and amplitude modulation (SHE-PWAM) control strategy results in significant improvements in the performance of CHB inverters. This fact is due to considerin...

  2. Pulse-width modulated DC-DC power converters

    CERN Document Server

    Kazimierczuk, Marian K

    2008-01-01

    This book studies switch-mode power supplies (SMPS) in great detail. This type of converter changes an unregulated DC voltage into a high-frequency pulse-width modulated (PWM) voltage controlled by varying the duty cycle, then changes the PWM AC voltage to a regulated DC voltage at a high efficiency by rectification and filtering. Used to supply electronic circuits, this converter saves energy and space in the overall system. With concept-orientated explanations, this book offers state-of-the-art SMPS technology and promotes an understanding of the principle operations of PWM converters,

  3. Energy detection UWB system based on pulse width modulation

    Directory of Open Access Journals (Sweden)

    Song Cui

    2014-05-01

    Full Text Available A new energy detection ultra-wideband system based on pulse width modulation is proposed. The bit error rate (BER performance of this new system is slightly worst than that of a pulse position modulation (PPM system in additive white Gaussian noise channels. In multipath channels, this system does not suffer from cross-modulation interference as PPM, so it can achieve better BER performance than PPM when cross-modulation interference occurs. In addition, when synchronisation errors occur, this system is more robust than PPM.

  4. Space Vector Pulse Width Modulation of a Multi-Level Diode ...

    African Journals Online (AJOL)

    Space Vector Pulse Width Modulation of a Multi-Level Diode Clamped ... of MATLAB /SIMULINK modeling of the space vector pulse-width modulation and the ... two adjacent active vectors in determining the switching process of the multilevel ...

  5. Suppression of high-frequency perturbations in pulse-width modulation

    DEFF Research Database (Denmark)

    2008-01-01

    A method suppresses high-frequency perturbations in a pulse-width modulated signal. The pulse-width modulation may superpose a carrier signal onto an input signal having a predetermined modulation frequency. The carrier signals may be phase-shifted. The resulting modulated signals may...

  6. Object width modulates object-based attentional selection.

    Science.gov (United States)

    Nah, Joseph C; Neppi-Modona, Marco; Strother, Lars; Behrmann, Marlene; Shomstein, Sarah

    2018-04-24

    Visual input typically includes a myriad of objects, some of which are selected for further processing. While these objects vary in shape and size, most evidence supporting object-based guidance of attention is drawn from paradigms employing two identical objects. Importantly, object size is a readily perceived stimulus dimension, and whether it modulates the distribution of attention remains an open question. Across four experiments, the size of the objects in the display was manipulated in a modified version of the two-rectangle paradigm. In Experiment 1, two identical parallel rectangles of two sizes (thin or thick) were presented. Experiments 2-4 employed identical trapezoids (each having a thin and thick end), inverted in orientation. In the experiments, one end of an object was cued and participants performed either a T/L discrimination or a simple target-detection task. Combined results show that, in addition to the standard object-based attentional advantage, there was a further attentional benefit for processing information contained in the thick versus thin end of objects. Additionally, eye-tracking measures demonstrated increased saccade precision towards thick object ends, suggesting that Fitts's Law may play a role in object-based attentional shifts. Taken together, these results suggest that object-based attentional selection is modulated by object width.

  7. Enhancement of mosquito trapping efficiency by using pulse width modulated light emitting diodes

    OpenAIRE

    Liu, Yu-Nan; Liu, Yu-Jen; Chen, Yi-Chian; Ma, Hsin-Yi; Lee, Hsiao-Yi

    2017-01-01

    In this study, a light-driving bug zapper is presented for well controlling the diseases brought by insects, such as mosquitoes. In order to have the device efficient to trap the insect pests in off-grid areas, pulse width modulated light emitting diodes (PWM-LED) combined with a solar power module are proposed and implemented. With specific PWM electric signals to drive the LED, it is found that no matter what the ability of catching insects or the consumed power efficiency can be enhanced t...

  8. Effect of different methods of pulse width modulation on power losses in an induction motor

    Science.gov (United States)

    Gulyaev, Alexander; Fokin, Dmitrii; Shuharev, Sergey; Ten, Evgenii

    2017-10-01

    We consider the calculation of modulation power losses in a system “induction motor-inverter” for various pulse width modulation (PWM) methods of the supply voltage. Presented values of modulation power losses are the result of modeling a system “DC link - two-level three-phase voltage inverter - induction motor - load”. In this study the power losses in a system “induction motor - inverter” are computed, as well as losses caused by higher harmonics of PWM supply voltage, followed by definition of active power consumed by the DC link for a specified value mechanical power on the induction motor shaft. Mechanical power was determined by the rotation speed and the torque on the motor shaft in various quasi-sinusoidal supply voltage PWM modes. These calculations reveal the best coefficient of performance (COP) in a system of a variable frequency drive (VFD) with independent voltage inverter controlled by induction motor PWM.

  9. Losses analysis of soft magnetic ring core under sinusoidal pulse width modulation (SPWM) and space vector pulse width modulation (SVPWM) excitations

    Science.gov (United States)

    Gao, Hezhe; Li, Yongjian; Wang, Shanming; Zhu, Jianguo; Yang, Qingxin; Zhang, Changgeng; Li, Jingsong

    2018-05-01

    Practical core losses in electrical machines differ significantly from those experimental results using the standardized measurement method, i.e. Epstein Frame method. In order to obtain a better approximation of the losses in an electrical machine, a simulation method considering sinusoidal pulse width modulation (SPWM) and space vector pulse width modulation (SVPWM) waveforms is proposed. The influence of the pulse width modulation (PWM) parameters on the harmonic components in SPWM and SVPWM is discussed by fast Fourier transform (FFT). Three-level SPWM and SVPWM are analyzed and compared both by simulation and experiment. The core losses of several ring samples magnetized by SPWM, SVPWM and sinusoidal alternating current (AC) are obtained. In addition, the temperature rise of the samples under SPWM, sinusoidal excitation are analyzed and compared.

  10. Laboratory manual for pulse-width modulated DC-DC power converters

    CERN Document Server

    Kazimierczuk, Marian K

    2015-01-01

    Designed to complement a range of power electronics study resources, this unique lab manual helps students to gain a deep understanding of the operation, modeling, analysis, design, and performance of pulse-width modulated (PWM) DC-DC power converters.  Exercises focus on three essential areas of power electronics: open-loop power stages; small-signal modeling, design of feedback loops and PWM DC-DC converter control schemes; and semiconductor devices such as silicon, silicon carbide and gallium nitride. Meeting the standards required by industrial employers, the lab manual combines program

  11. Thermal conductivity engineering in width-modulated silicon nanowires and thermoelectric efficiency enhancement

    Science.gov (United States)

    Zianni, Xanthippi

    2018-03-01

    Width-modulated nanowires have been proposed as efficient thermoelectric materials. Here, the electron and phonon transport properties and the thermoelectric efficiency are discussed for dimensions above the quantum confinement regime. The thermal conductivity decreases dramatically in the presence of thin constrictions due to their ballistic thermal resistance. It shows a scaling behavior upon the width-modulation rate that allows for thermal conductivity engineering. The electron conductivity also decreases due to enhanced boundary scattering by the constrictions. The effect of boundary scattering is weaker for electrons than for phonons and the overall thermoelectric efficiency is enhanced. A ZT enhancement by a factor of 20-30 is predicted for width-modulated nanowires compared to bulk silicon. Our findings indicate that width-modulated nanostructures are promising for developing silicon nanostructures with high thermoelectric efficiency.

  12. Enhancement of mosquito trapping efficiency by using pulse width modulated light emitting diodes

    Science.gov (United States)

    Liu, Yu-Nan; Liu, Yu-Jen; Chen, Yi-Chian; Ma, Hsin-Yi; Lee, Hsiao-Yi

    2017-01-01

    In this study, a light-driving bug zapper is presented for well controlling the diseases brought by insects, such as mosquitoes. In order to have the device efficient to trap the insect pests in off-grid areas, pulse width modulated light emitting diodes (PWM-LED) combined with a solar power module are proposed and implemented. With specific PWM electric signals to drive the LED, it is found that no matter what the ability of catching insects or the consumed power efficiency can be enhanced thus. It is demonstrated that 40% of the UV LED consumed power and 25.9% of the total load power consumption can be saved, and the trapped mosquitoes are about 250% increased when the PWM method is applied in the bug zapper experiments.

  13. Capacitor charging FET switcher with controller to adjust pulse width

    Science.gov (United States)

    Mihalka, Alex M.

    1986-01-01

    A switching power supply includes an FET full bridge, a controller to drive the FETs, a programmable controller to dynamically control final output current by adjusting pulse width, and a variety of protective systems, including an overcurrent latch for current control. Power MOSFETS are switched at a variable frequency from 20-50 kHz to charge a capacitor load from 0 to 6 kV. A ferrite transformer steps up the DC input. The transformer primary is a full bridge configuration with the FET switches and the secondary is fed into a high voltage full wave rectifier whose output is connected directly to the energy storage capacitor. The peak current is held constant by varying the pulse width using predetermined timing resistors and counting pulses. The pulse width is increased as the capacitor charges to maintain peak current. A digital ripple counter counts pulses, and after the desired number is reached, an up-counter is clocked. The up-counter output is decoded to choose among different resistors used to discharge a timing capacitor, thereby determining the pulse width. A current latch shuts down the supply on overcurrent due to either excessive pulse width causing transformer saturation or a major bridge fault, i.e., FET or transformer failure, or failure of the drive circuitry.

  14. Pulse width modulation based pneumatic frequency tuner of the superconducting resonators at IUAC

    International Nuclear Information System (INIS)

    Pandey, A.; Suman, S.K.; Mathuria, D.S.

    2015-01-01

    The existing phase locking scheme of the quarter wave resonators (QWR) used in superconducting linear accelerator (LINAC) of IUAC consists of a fast time (electronic) and a slow time (pneumatic) control. Presently, piezo based mechanical tuners are being used to phase lock the resonators installed in the second and third accelerating modules of LINAC. However, due to space constraint, the piezo tuner can't be implemented on the resonators of the first accelerating module. Therefore, helium gas operated mechanical tuners are being used to phase lock the resonators against the master oscillator (MO) frequency. The present pneumatic frequency tuner has limitations of non-linearity, hysteresis and slow response time. To overcome these problems and to improve the dynamics of the existing tuner, a new pulse width modulation (PWM) based pneumatic frequency tuning system was adopted and successfully tested. After successful test, the PWM based pneumatic frequency tuner was installed in four QWR of the first accelerating module of LINAC. During beam run the PWM based frequency tuner performed well and the cavities could be phase locked at comparatively higher accelerating fields. A comparison of the existing tuning mechanism and the PWM based tuning system along with the test results will be presented in the paper. (author)

  15. Double-Carrier Phase-Disposition Pulse Width Modulation Method for Modular Multilevel Converters

    DEFF Research Database (Denmark)

    Zhou, Fayun; Luo, An; Li, Yan

    2017-01-01

    Modular multilevel converters (MMCs) have become one of the most attractive topologies for high-voltage and high-power applications. A double-carrier phase disposition pulse width modulation (DCPDPWM) method for MMCs is proposed in this paper. Only double triangular carriers with displacement ang......, the proposed method and theoretical analysis are verified by simulation and experimental results. View Full-Text...

  16. Optimal time-domain technique for pulse width modulation in power electronics

    Directory of Open Access Journals (Sweden)

    I. Mayergoyz

    2018-05-01

    Full Text Available Optimal time-domain technique for pulse width modulation is presented. It is based on exact and explicit analytical solutions for inverter circuits, obtained for any sequence of input voltage rectangular pulses. Two optimal criteria are discussed and illustrated by numerical examples.

  17. Equalization of Skin Effect Loss Dominated Channels using Pulse-Width Modulation (PWM) Pre-Emphasis

    NARCIS (Netherlands)

    Schrader, J.H.R.; Klumperink, Eric A.M.; Visschers, J.L.; Nauta, Bram

    2005-01-01

    A digital transmitter pre-emphasis technique is presented that is based on pulse-width modulation, instead of finite impulse response (FIR) filtering. The technique fits well to future high-speed low-voltage CMOS processes. A 0.13μm CMOS transmitter achieves more than 5Gb/s (2-PAM) over 25m of

  18. A two-level voltage source inverter with differentially sinusoidal pulse width modulation used in the interconnection system of a wind turbine generator

    Directory of Open Access Journals (Sweden)

    Alexandros C. Charalampidis

    2014-10-01

    Full Text Available This study analyses an interconnection system based on differentially sinusoidal pulse width modulation, used for the interconnection to the grid of a variable speed wind turbine. The modulation technique used provides specific advantages in comparison with the commonly used sinusoidal pulse width modulation (SPWM technique, such as lower DC bus voltage requirements, smaller switching losses for the same switching frequency as well as less higher harmonic content in the voltage waveforms produced. The respective control system is also described in detail. Thus this study provides a guide enabling the design of any interconnection system based on this modulation technique.

  19. New hybrid reverse differential pulse position width modulation scheme for wireless optical communication

    Science.gov (United States)

    Liao, Renbo; Liu, Hongzhan; Qiao, Yaojun

    2014-05-01

    In order to improve the power efficiency and reduce the packet error rate of reverse differential pulse position modulation (RDPPM) for wireless optical communication (WOC), a hybrid reverse differential pulse position width modulation (RDPPWM) scheme is proposed, based on RDPPM and reverse pulse width modulation. Subsequently, the symbol structure of RDPPWM is briefly analyzed, and its performance is compared with that of other modulation schemes in terms of average transmitted power, bandwidth requirement, and packet error rate over ideal additive white Gaussian noise (AWGN) channels. Based on the given model, the simulation results show that the proposed modulation scheme has the advantages of improving the power efficiency and reducing the bandwidth requirement. Moreover, in terms of error probability performance, RDPPWM can achieve a much lower packet error rate than that of RDPPM. For example, at the same received signal power of -28 dBm, the packet error rate of RDPPWM can decrease to 2.6×10-12, while that of RDPPM is 2.2×10. Furthermore, RDPPWM does not need symbol synchronization at the receiving end. These considerations make RDPPWM a favorable candidate to select as the modulation scheme in the WOC systems.

  20. PSCAD modeling of a two-level space vector pulse width modulation algorithm for power electronics education

    Directory of Open Access Journals (Sweden)

    Ahmet Mete Vural

    2016-09-01

    Full Text Available This paper presents the design details of a two-level space vector pulse width modulation algorithm in PSCAD that is able to generate pulses for three-phase two-level DC/AC converters with two different switching patterns. The presented FORTRAN code is generic and can be easily modified to meet many other kinds of space vector modulation strategies. The code is also editable for hardware programming. The new component is tested and verified by comparing its output as six gating signals with those of a similar component in MATLAB library. Moreover the component is used to generate digital signals for closed-loop control of STATCOM for reactive power compensation in PSCAD. This add-on can be an effective tool to give students better understanding of the space vector modulation algorithm for different control tasks in power electronics area, and can motivate them for learning.

  1. Pulsed rf excited spectrometer having improved pulse width control

    International Nuclear Information System (INIS)

    1977-01-01

    RF excitation for a spectrometer is obtained by pulse width modulating an RF carrier to produce the desired broadband RF exciting spectrum. The RF excitation includes a train of composite RF pulses, each composite pulse having a primary pulse portion of a first RF phase and a second pulse portion of a second RF phase opposite that of the first. In this manner, the finite rise and fall times of the primary pulse portion are compensated for by the corresponding rise and fall times of the secondary pulse portion. The primary pulse portion is lengthened by an amount equal to the secondary pulse portion so that the secondary pulse portion cancels the added primary pulse portion. In a spectrometer, the compensating second pulse component removes certain undesired side bands of the RF excitation caused by the finite rise and fall times of the applied RF pulses. The compensating second pulse component removes certain undesired side bands associated with each of the resonant lines of the excited resonance spectrum of the sample under analysis, particularly for wide band RF excitation

  2. Liquid mixing enhanced by pulse width modulation in a Y-shaped jet configuration

    Science.gov (United States)

    Xia, Qingfeng; Zhong, Shan

    2013-04-01

    In this paper, mixing between two fluid streams, which are injected into a planar mixing channel via a Y-shaped confluence section at the same volume flow rate, is studied experimentally. The injection of the two fluid streams is controlled by two separate solenoid valves, which are operated with a phase difference of 180°, using pulse width modulation. The experiments are conducted using water at a mean Reynolds number between 83 and 250, a range of pulsation frequencies and two duty cycles (25 and 50%). Both particle-image velocimetry and planar laser-induced fluorescence technique are used to visualize the flow patterns and to quantify the mixing degree in the mixing channel. This experiment shows that the pulsation of each jet produces vortical structures, which promotes mixing via vortex entrainment and vortex breakup, and at the same time the mixing is also greatly enhanced by sequential segmentation produced by a 180° out-of-phase pulsation of the two jets. This mixing enhancement method is effective at a Reynolds number greater than 125 with a mixing degree of 0.9 being achieved. For the Reynolds numbers studied in the present experiments, an optimal frequency exists, which corresponds to a Strouhal number in the range of 0.5-2. Furthermore, at a given mean Reynolds number a lower duty cycle is found to produce a better mixing due to the resultant higher instantaneous Reynolds number in the jet flow. It is also found that pulsation of only one jet can produce a similar mixing effect.

  3. Liquid mixing enhanced by pulse width modulation in a Y-shaped jet configuration

    Energy Technology Data Exchange (ETDEWEB)

    Xia Qingfeng; Zhong Shan, E-mail: shan.zhong@manchester.ac.uk [School of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester M13 9PL (United Kingdom)

    2013-04-15

    In this paper, mixing between two fluid streams, which are injected into a planar mixing channel via a Y-shaped confluence section at the same volume flow rate, is studied experimentally. The injection of the two fluid streams is controlled by two separate solenoid valves, which are operated with a phase difference of 180 Degree-Sign , using pulse width modulation. The experiments are conducted using water at a mean Reynolds number between 83 and 250, a range of pulsation frequencies and two duty cycles (25 and 50%). Both particle-image velocimetry and planar laser-induced fluorescence technique are used to visualize the flow patterns and to quantify the mixing degree in the mixing channel. This experiment shows that the pulsation of each jet produces vortical structures, which promotes mixing via vortex entrainment and vortex breakup, and at the same time the mixing is also greatly enhanced by sequential segmentation produced by a 180 Degree-Sign out-of-phase pulsation of the two jets. This mixing enhancement method is effective at a Reynolds number greater than 125 with a mixing degree of 0.9 being achieved. For the Reynolds numbers studied in the present experiments, an optimal frequency exists, which corresponds to a Strouhal number in the range of 0.5-2. Furthermore, at a given mean Reynolds number a lower duty cycle is found to produce a better mixing due to the resultant higher instantaneous Reynolds number in the jet flow. It is also found that pulsation of only one jet can produce a similar mixing effect. (paper)

  4. Decoupled Modulation Control

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shaobu; Huang, Renke; Huang, Zhenyu; Diao, Ruisheng

    2016-06-03

    The objective of this research work is to develop decoupled modulation control methods for damping inter-area oscillations with low frequencies, so the damping control can be more effective and easier to design with less interference among different oscillation modes in the power system. A signal-decoupling algorithm was developed that can enable separation of multiple oscillation frequency contents and extraction of a “pure” oscillation frequency mode that are fed into Power System Stabilizers (PSSs) as the modulation input signals. As a result, instead of introducing interferences between different oscillation modes from the traditional approaches, the output of the new PSS modulation control signal mainly affects only one oscillation mode of interest. The new decoupled modulation damping control algorithm has been successfully developed and tested on the standard IEEE 4-machine 2-area test system and a minniWECC system. The results are compared against traditional modulation controls, which demonstrates the validity and effectiveness of the newly-developed decoupled modulation damping control algorithm.

  5. Solution of the pulse width modulation problem using orthogonal polynomials and Korteweg-de Vries equations.

    Science.gov (United States)

    Chudnovsky, D V; Chudnovsky, G V

    1999-10-26

    The mathematical underpinning of the pulse width modulation (PWM) technique lies in the attempt to represent "accurately" harmonic waveforms using only square forms of a fixed height. The accuracy can be measured using many norms, but the quality of the approximation of the analog signal (a harmonic form) by a digital one (simple pulses of a fixed high voltage level) requires the elimination of high order harmonics in the error term. The most important practical problem is in "accurate" reproduction of sine-wave using the same number of pulses as the number of high harmonics eliminated. We describe in this paper a complete solution of the PWM problem using Pade approximations, orthogonal polynomials, and solitons. The main result of the paper is the characterization of discrete pulses answering the general PWM problem in terms of the manifold of all rational solutions to Korteweg-de Vries equations.

  6. Porous Alumina Films with Width-Controllable Alumina Stripes

    Directory of Open Access Journals (Sweden)

    Huang Shi-Ming

    2010-01-01

    Full Text Available Abstract Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure of the aluminum surface.

  7. Porous Alumina Films with Width-Controllable Alumina Stripes

    Science.gov (United States)

    2010-01-01

    Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure of the aluminum surface. PMID:21170406

  8. Adjustable focus laser sheet module for generating constant maximum width sheets for use in optical flow diagnostics

    International Nuclear Information System (INIS)

    Hult, J; Mayer, S

    2011-01-01

    A general design of a laser light sheet module with adjustable focus is presented, where the maximum sheet width is preserved over a fixed region. In contrast, conventional focusing designs are associated with a variation in maximum sheet width with focal position. A four lens design is proposed here, where the first three lenses are employed for focusing, and the last for sheet expansion. A maximum sheet width of 1100 µm was maintained over a 50 mm long distance, for focal distances ranging from 75 to 500 mm, when a 532 nm laser beam with a beam quality factor M 2 = 29 was used for illumination

  9. Pulse-width modulation for small heat pump installations - Phase 2: implementation in a commercial controller and tests in a residential building; Pulsbreitenmodulation fuer Kleinwaermepumpenanlagen. Phase 2: Implementierung in handelsuebliche Regler und Erprobung in einem Wohnhaus

    Energy Technology Data Exchange (ETDEWEB)

    Gabathuler, H.R.; Mayer, H. [Gabathuler AG, Diessenhofen (Switzerland); Shafai, E.; Wimmer, R. [Eidgenoessische Technische Hochschule, Institut fuer Mess- und Regeltechnik, Zuerich (Switzerland); Frei, R. [Satag Thermotechnik AG, Arbon (Switzerland); Illi, B.; Sidler, F. [Siemens Building Technologies AG, Zug (Switzerland)

    2002-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) presents the results of a project in which a new type of controller for small heat pumps used to heat single-family houses was developed. Instead of the two-point controller normally used to control flow or return temperatures in the heating system, three new approaches are described that deliver the heating energy required for a whole day in portions according to prevailing weather conditions and the thermal characteristics of the house and the heat pump. Electricity tariffs are also taken into account and peak-rate periods avoided. The results of the investigations show that all three variants can be implemented using commercially available controllers. Further investigations, including a complete and representative comparison of the three concepts and a conventional control system are foreseen in phase 3 of the project.

  10. Space Vector Pulse Width Modulation Strategy for Single-Phase Three-Level CIC T-source Inverter

    DEFF Research Database (Denmark)

    Shults, Tatiana E.; Husev, Oleksandr O.; Blaabjerg, Frede

    2016-01-01

    This paper presents a novel space vector pulse-width modulation strategy for a single-phase three-level buck-boost inverter based on an impedance-source network. The case study system is based on T-source inverter with continuous input current. To demonstrate the improved performance of the inver......This paper presents a novel space vector pulse-width modulation strategy for a single-phase three-level buck-boost inverter based on an impedance-source network. The case study system is based on T-source inverter with continuous input current. To demonstrate the improved performance...... of the inverter, the strategy was compared the traditional pulse-width modulation. It is shown that the approach proposed has fewer switching states and does not suffer from neutral point misbalance....

  11. Dosimetric effect of multileaf collimator leaf width on volumetric modulated arc stereotactic radiotherapy for spine tumors

    Energy Technology Data Exchange (ETDEWEB)

    Amoush, Ahmad, E-mail: aamoush@augusta.edu [Augusta University, 1120 15th St, Augusta, GA 30912 (United States); Cleveland Clinic, 9500 Euclid Ave., Cleveland, OH 44195 (United States); Long, Huang [University of Utah, 1950 Circle of Hope, Salt Lake City, UT 84112 (United States); Subedi, Laxmi [Cleveland State University, 2121 Euclid Ave., Cleveland, OH 44115 (United States); Qi, Peng; Djemil, Toufik; Xia, Ping [Cleveland Clinic, 9500 Euclid Ave., Cleveland, OH 44195 (United States)

    2017-07-01

    This work aimed to study the dosimetric effect of multileaf collimator (MLC) leaf widths in treatment plans for patients receiving volumetric modulated arc therapy (VMAT) for spine stereotactic body radiation therapy (SBRT). Thirteen patients treated with spine SBRT were retrospectively selected for this study. The patients were treated following the protocol of the Radiation Therapy Oncology Group 0631 (RTOG 0631) for spine metastasis. The prescription dose was 16 Gy in 1 fraction to 90% of the target volume (V16 > 90%). The maximum spinal cord dose of 14 Gy and 10% of the spinal cord receiving < 10 Gy (V10) were the acceptable tolerance doses. For the purpose of this study, 2 dual-arc VMAT plans were created for each patient using 3 different MLC leaf widths: 2.5 mm, 4 mm, and 5 mm. The compliance with the RTOG 0631 protocol, conformity index (CI), dose gradient index (DGI), and number of monitor units (MUs) were compared. The average V16Gy of the targets was 91.8 ± 1.2%, 92.2 ± 2.1%, and 91.7 ± 2.3% for 2.5-mm, 4-mm, and 5-mm leaf widths, respectively (p = 0.78). Accordingly, the average CI was 1.45 ± 0.4, 1.47 ± 0.29, and 1.47 ± 0.31 (p = 0.98), respectively. The average DGI was 0.22 ± 0.04, 0.20 ± 0.06, and 0.22 ± 0.05, respectively (p = 0.77). The average maximum dose to the spinal cord was 12.45 ± 1.0 Gy, 12.80 ± 1.0 Gy, and 12.48 ± 1.1 (p = 0.62) and V10% of the spinal cord was 3.6 ± 2.1%, 5.6 ± 2.8%, and 5.5 ± 3.0% (p = 0.11) for 2.5-mm, 4-mm, and 5-mm leaf widths, respectively. Accordingly, the average number of MUs was 4341 ± 500 MU, 5019 ± 834 MU, and 4606 ± 691 MU, respectively (p = 0.053). The use of 2.5-mm, 4-mm, and 5-mm MLCs achieved similar VMAT plan quality as recommended by the RTOG 0631. The dosimetric parameters were also comparable for the 3 MLCs. In general, any of these leaf widths can be used for spine

  12. A frequency and pulse-width co-modulation strategy for transcutaneous neuromuscular electrical stimulation based on sEMG time-domain features

    Science.gov (United States)

    Zhou, Yu-Xuan; Wang, Hai-Peng; Bao, Xue-Liang; Lü, Xiao-Ying; Wang, Zhi-Gong

    2016-02-01

    Objective. Surface electromyography (sEMG) is often used as a control signal in neuromuscular electrical stimulation (NMES) systems to enhance the voluntary control and proprioceptive sensory feedback of paralyzed patients. Most sEMG-controlled NMES systems use the envelope of the sEMG signal to modulate the stimulation intensity (current amplitude or pulse width) with a constant frequency. The aims of this study were to develop a strategy that co-modulates frequency and pulse width based on features of the sEMG signal and to investigate the torque-reproduction performance and the level of fatigue resistance achieved with our strategy. Approach. We examined the relationships between wrist torque and two stimulation parameters (frequency and pulse width) and between wrist torque and two sEMG time-domain features (mean absolute value (MAV) and number of slope sign changes (NSS)) in eight healthy volunteers. By using wrist torque as an intermediate variable, customized and generalized transfer functions were constructed to convert the two features of the sEMG signal into the two stimulation parameters, thereby establishing a MAV/NSS dual-coding (MNDC) algorithm. Wrist torque reproduction performance was assessed by comparing the torque generated by the algorithms with that originally recorded during voluntary contractions. Muscle fatigue was assessed by measuring the decline percentage of the peak torque and by comparing the torque time integral of the response to test stimulation trains before and after fatigue sessions. Main Results. The MNDC approach could produce a wrist torque that closely matched the voluntary wrist torque. In addition, a smaller decay in the wrist torque was observed after the MNDC-coded fatigue stimulation was applied than after stimulation using pulse-width modulation alone. Significance. Compared with pulse-width modulation stimulation strategies that are based on sEMG detection, the MNDC strategy is more effective for both voluntary muscle

  13. Data acquisition electronics for gamma ray emission tomography using width-modulated leading-edge discriminators

    Energy Technology Data Exchange (ETDEWEB)

    Lage, E; Tapias, G; Villena, J; Desco, M; Vaquero, J J, E-mail: desco@mce.hggm.e [Unidad de Medicina y CirugIa Experimental, Hospital General Universitario Gregorio Maranon, Madrid (Spain)

    2010-08-07

    We present a new high-performance and low-cost approach for implementing radiation detection acquisition systems. The basic elements used are charge-integrating ADCs and a set of components encapsulated in an HDL (hardware definition language) library which makes it possible to implement several acquisition tasks such as time pickoff and coincidence detection using a new and simple trigger technique that we name WMLET (width-modulated leading-edge timing). As proof of concept, a 32-channel hybrid PET/SPECT acquisition system based on these elements was developed and tested. This demonstrator consists of a master module responsible for the generation and distribution of trigger signals, 2 x 16-channel ADC cards (12-bit resolution) for data digitization and a 32-bit digital I/O PCI card for handling data transmission to a personal computer. System characteristics such as linearity, maximum transmission rates or timing resolution in coincidence mode were evaluated with test and real detector signals. Imaging capabilities of the prototype were also evaluated using different detector configurations. The performance tests showed that this implementation is able to handle data rates in excess of 600k events s{sup -1} when acquiring simultaneously 32 channels (96-byte events). ADC channel linearity is >98.5% in energy quantification. Time resolution in PET mode for the tested configurations ranges from 3.64 ns FWHM to 7.88 ns FWHM when signals from LYSO-based detectors are used. The measured energy resolution matched the expected values for the detectors evaluated and single elements of crystal matrices can be neatly separated in the acquired flood histograms.

  14. Data acquisition electronics for gamma ray emission tomography using width-modulated leading-edge discriminators

    Science.gov (United States)

    Lage, E.; Tapias, G.; Villena, J.; Desco, M.; Vaquero, J. J.

    2010-08-01

    We present a new high-performance and low-cost approach for implementing radiation detection acquisition systems. The basic elements used are charge-integrating ADCs and a set of components encapsulated in an HDL (hardware definition language) library which makes it possible to implement several acquisition tasks such as time pickoff and coincidence detection using a new and simple trigger technique that we name WMLET (width-modulated leading-edge timing). As proof of concept, a 32-channel hybrid PET/SPECT acquisition system based on these elements was developed and tested. This demonstrator consists of a master module responsible for the generation and distribution of trigger signals, 2 × 16-channel ADC cards (12-bit resolution) for data digitization and a 32-bit digital I/O PCI card for handling data transmission to a personal computer. System characteristics such as linearity, maximum transmission rates or timing resolution in coincidence mode were evaluated with test and real detector signals. Imaging capabilities of the prototype were also evaluated using different detector configurations. The performance tests showed that this implementation is able to handle data rates in excess of 600k events s-1 when acquiring simultaneously 32 channels (96-byte events). ADC channel linearity is >98.5% in energy quantification. Time resolution in PET mode for the tested configurations ranges from 3.64 ns FWHM to 7.88 ns FWHM when signals from LYSO-based detectors are used. The measured energy resolution matched the expected values for the detectors evaluated and single elements of crystal matrices can be neatly separated in the acquired flood histograms.

  15. SWITCH MODE PULSE WIDTH MODULATED DC-DC CONVERTER WITH MULTIPLE POWER TRANSFORMERS

    DEFF Research Database (Denmark)

    2009-01-01

    A switch mode pulse width modulated DC-DC power converter comprises at least one first electronic circuit on a input side (1) and a second electronic circuit on a output side (2). The input side (1) and the output side (2) are coupled via at least two power transformers (T1, T2). Each power...... transformer (T1, T2) comprises a first winding (T1a, T2a) arranged in a input side converter stage (3, 4) on the input side (1) and a second winding (T1 b, T2b) arranged in a output side converter stage (5) on the output side (2), and each of the windings (T1a, T1 b, T2a, T2b) has a first end and a second end....... The first electronic circuit comprises terminals (AO, A1) for connecting a source or a load, at least one energy storage inductor (L) coupled in series with at least one of the first windings (T1a, T2a) of the power transformers (T1, T2), and for each power transformer (T1, T2), an arrangement of switches...

  16. Using Pulse Width Modulation for Wireless Transmission of Neural Signals in Multichannel Neural Recording Systems

    Science.gov (United States)

    Yin, Ming; Ghovanloo, Maysam

    2013-01-01

    We have used a well-known technique in wireless communication, pulse width modulation (PWM) of time division multiplexed (TDM) signals, within the architecture of a novel wireless integrated neural recording (WINeR) system. We have evaluated the performance of the PWM-based architecture and indicated its accuracy and potential sources of error through detailed theoretical analysis, simulations, and measurements on a setup consisting of a 15-channel WINeR prototype as the transmitter and two types of receivers; an Agilent 89600 vector signal analyzer and a custom wideband receiver, with 36 and 75 MHz of maximum bandwidth, respectively. Furthermore, we present simulation results from a realistic MATLAB-Simulink model of the entire WINeR system to observe the system behavior in response to changes in various parameters. We have concluded that the 15-ch WINeR prototype, which is fabricated in a 0.5-μm standard CMOS process and consumes 4.5 mW from ±1.5 V supplies, can acquire and wirelessly transmit up to 320 k-samples/s to a 75-MHz receiver with 8.4 bits of resolution, which is equivalent to a wireless data rate of ~ 2.26 Mb/s. PMID:19497823

  17. Analysis and Minimization of Output Current Ripple for Discontinuous Pulse-Width Modulation Techniques in Three-Phase Inverters

    Directory of Open Access Journals (Sweden)

    Gabriele Grandi

    2016-05-01

    Full Text Available This paper gives the complete analysis of the output current ripple in three-phase voltage source inverters considering the different discontinuous pulse-width modulation (DPWM strategies. In particular, peak-to-peak current ripple amplitude is analytically evaluated over the fundamental period and compared among the most used DPWMs, including positive and negative clamped (DPWM+ and DPWM−, and the four possible combinations between them, usually named as DPWM0, DPWM1, DPWM2, and DPWM3. The maximum and the average values of peak-to-peak current ripple are estimated, and a simple method to correlate the ripple envelope with the ripple rms is proposed and verified. Furthermore, all the results obtained by DPWMs are compared to the centered pulse-width modulation (CPWM, equivalent to the space vector modulation to identify the optimal pulse-width modulation (PWM strategy as a function of the modulation index, taking into account the different average switching frequency. In this way, the PWM technique providing for the minimum output current ripple is identified over the whole modulation range. The analytical developments and the main results are experimentally verified by current ripple measurements with a three-phase PWM inverter prototype supplying an induction motor load.

  18. Pulse width modulated buck-boost five-level current source inverters

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Gao, F.; Loh, P.C.

    2008-01-01

    , resulting in the natural balance of input current. For maintaining the normalized volt-sec average unchanged, the alternative phase opposition disposition (APOD) modulation scheme with typical gating signal mapping technique from voltage source inverter (VSI) to CSI can be assumed to control the five......This paper presents new five-level current source inverters (CSIs) with voltage/current buck-boost capability. Being different from the existing multilevel CSI, the proposed CSIs were first designed to regulate the flowing path of dc input current by controlling two additional active switches......-level buck-boost CSIs. Next by observing the hidden current charging path during inductive charging interval under APOD modulation, it is noted that the buck-boost five-level CSI can then be further modified with lesser active component without degrading output performance. To verify the theoretical findings...

  19. Pulse width and height modulation for multi-level resistance in bi-layer TaOx based RRAM

    Science.gov (United States)

    Alamgir, Zahiruddin; Beckmann, Karsten; Holt, Joshua; Cady, Nathaniel C.

    2017-08-01

    Mutli-level switching in resistive memory devices enables a wide range of computational paradigms, including neuromorphic and cognitive computing. To this end, we have developed a bi-layer tantalum oxide based resistive random access memory device using Hf as the oxygen exchange layer. Multiple, discrete resistance levels were achieved by modulating the RESET pulse width and height, ranging from 2 kΩ to several MΩ. For a fixed pulse height, OFF state resistance was found to increase gradually with the increase in the pulse width, whereas for a fixed pulse width, the increase in the pulse height resulted in drastic changes in resistance. Resistive switching in these devices transitioned from Schottky emission in the OFF state to tunneling based conduction in the ON state, based on I-V curve fitting and temperature dependent current measurements. These devices also demonstrated endurance of more than 108 cycles with a satisfactory Roff/Ron ratio and retention greater than 104 s.

  20. space vector pulse width modulation of a multi-level diode clamped

    African Journals Online (AJOL)

    ES Obe

    step by step development of MATLAB /SIMULINK modeling of the space vector ..... Pulse Width Mod. of Multi-Level Diode Clamped Converter 119 powergui. Discrete, .... Load. Figure 22: Block diagram of the three level DCC design. 3 LEVEL ...

  1. The theory and implementation of a high quality pulse width modulated waveform synthesiser applicable to voltage FED inverters

    Science.gov (United States)

    Lower, Kim Nigel

    1985-03-01

    Modulation processes associated with the digital implementation of pulse width modulation (PWM) switching strategies were examined. A software package based on a portable turnkey structure is presented. Waveform synthesizer implementation techniques are reviewed. A three phase PWM waveform synthesizer for voltage fed inverters was realized. It is based on a constant carrier frequency of 18 kHz and a regular sample, single edge, asynchronous PWM switching scheme. With high carrier frequencies, it is possible to utilize simple switching strategies and as a consequence, many advantages are highlighted, emphasizing the importance to industrial and office markets.

  2. Effects of walking speed on the step-by-step control of step width.

    Science.gov (United States)

    Stimpson, Katy H; Heitkamp, Lauren N; Horne, Joscelyn S; Dean, Jesse C

    2018-02-08

    Young, healthy adults walking at typical preferred speeds use step-by-step adjustments of step width to appropriately redirect their center of mass motion and ensure mediolateral stability. However, it is presently unclear whether this control strategy is retained when walking at the slower speeds preferred by many clinical populations. We investigated whether the typical stabilization strategy is influenced by walking speed. Twelve young, neurologically intact participants walked on a treadmill at a range of prescribed speeds (0.2-1.2 m/s). The mediolateral stabilization strategy was quantified as the proportion of step width variance predicted by the mechanical state of the pelvis throughout a step (calculated as R 2 magnitude from a multiple linear regression). Our ability to accurately predict the upcoming step width increased over the course of a step. The strength of the relationship between step width and pelvis mechanics at the start of a step was reduced at slower speeds. However, these speed-dependent differences largely disappeared by the end of a step, other than at the slowest walking speed (0.2 m/s). These results suggest that mechanics-dependent adjustments in step width are a consistent component of healthy gait across speeds and contexts. However, slower walking speeds may ease this control by allowing mediolateral repositioning of the swing leg to occur later in a step, thus encouraging slower walking among clinical populations with limited sensorimotor control. Published by Elsevier Ltd.

  3. The impact of leaf width and plan complexity on DMLC tracking of prostate intensity modulated arc therapy

    DEFF Research Database (Denmark)

    Pommer, Tobias; Falk, Marianne; Poulsen, Per Rugaard

    2013-01-01

    Purpose: Intensity modulated arc therapy (IMAT) is commonly used to treat prostate cancer. The purpose of this study was to evaluate the impact of leaf width and plan complexity on dynamic multileaf collimator (DMLC) tracking for prostate motion management during IMAT treatments.Methods: Prostate...... IMAT plans were delivered with either a high-definition MLC (HDMLC) or a Millennium MLC (M-MLC) (0.25 and 0.50 cm central leaf width, respectively), with and without DMLC tracking, to a dosimetric phantom that reproduced four prostate motion traces. The plan complexity was varied by applying leaf....... The corresponding pass rates without tracking were 87.6% (range 76.2%-94.7%) and 91.1% (range 81.4%-97.6%), respectively. Decreased plan complexity improved the pass rate when static target measurements were used as reference, but not with the planned dose as reference. The main cause of tracking errors was leaf...

  4. A Temperature-Hardened Sensor Interface with a 12-Bit Digital Output Using a Novel Pulse Width Modulation Technique

    Directory of Open Access Journals (Sweden)

    Emna Chabchoub

    2018-04-01

    Full Text Available A fully integrated sensor interface for a wide operational temperature range is presented. It translates the sensor signal into a pulse width modulated (PWM signal that is then converted into a 12-bit digital output. The sensor interface is based on a pair of injection locked oscillators used to implement a differential time-domain architecture with low sensitivity to temperature variations. A prototype has been fabricated using a 180 nm partially depleted silicon-on-insulator (SOI technology. Experimental results demonstrate a thermal stability as low as 65 ppm/°C over a large temperature range from −20 °C up to 220 °C.

  5. Modular space-vector pulse-width modulation for nine-switch converters

    DEFF Research Database (Denmark)

    Dehghan, Seyed Mohammad; Amiri, Arash; Mohamadian, Mustafa

    2013-01-01

    Recently, nine-switch inverter (NSI) has been presented as a dual-output inverter with constant frequency (CF) or different frequency (DF) operation modes. However, the CF mode is more interesting because of its lower switching device rating. This study proposes a new space-vector modulation (SVM......) method for the NSI that supports both the CF and DF modes, whereas conventional SVM of NSI can be used only in the DF mode. The proposed SVM can be easily implemented based on the conventional six-switch inverter SVM modules. The performance of the proposed SVM is verified by the simulation...

  6. Pulse-width modulation for small heat pump installations - Phase 4; Pulsbreitenmodulation fuer Kleinwaermepumpenanlagen. Phase 4: Erweiterung der PBM-Regler fuer Kombianlagen

    Energy Technology Data Exchange (ETDEWEB)

    Bianchi, M.; Shafai, E. [Eidgenoessische Technische Hochschule (ETH), Institut fuer Mess- und Regeltechnik, Zuerich (Switzerland); Gabathuler, H.R.; Mayer, H. [Gabathuler AG, Beratende Ingenieure, Diessenhofen (Switzerland)

    2005-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) presents the results of the fourth phase of a project that investigated three types of pulse-width modulation (PWM) controllers that were developed during its first two phases. A third phase monitored the controllers when used in a simulated environment and for a real-life heat pump. The report discusses the fourth phase of the project, in which the controller was further developed and tested using the building emulation developed in the third phase. The functioning of the self-regulating controller and its use of meteorological data is described and the savings to be made in heating costs are discussed.

  7. Design of a variable width pulse generator feasible for manual or automatic control

    Energy Technology Data Exchange (ETDEWEB)

    Vegas, I., E-mail: ignacio.vegas@pas.ucm.es; Antoranz, P.; Miranda, J.M.; Franco, F.J.

    2017-01-01

    A variable width pulse generator featuring more than 4-V peak amplitude and less than 10-ns FWHM is described. In this design the width of the pulses is controlled by means of the control signal slope. Thus, a variable transition time control circuit (TTCC) is also developed, based on the charge and discharge of a capacitor by means of two tunable current sources. Additionally, it is possible to activate/deactivate the pulses when required, therefore allowing the creation of any desired pulse pattern. Furthermore, the implementation presented here can be electronically controlled. In conclusion, due to its versatility, compactness and low cost it can be used in a wide variety of applications.

  8. Breaking Through the Multi-Mesa-Channel Width Limited of Normally Off GaN HEMTs Through Modulation of the Via-Hole-Length.

    Science.gov (United States)

    Chien, Cheng-Yen; Wu, Wen-Hsin; You, Yao-Hong; Lin, Jun-Huei; Lee, Chia-Yu; Hsu, Wen-Ching; Kuan, Chieh-Hsiung; Lin, Ray-Ming

    2017-12-01

    We present new normally off GaN high-electron-mobility transistors (HEMTs) that overcome the typical limitations in multi-mesa-channel (MMC) width through modulation of the via-hole-length to regulate the charge neutrality screen effect. We have prepared enhancement-mode (E-mode) GaN HEMTs having widths of up to 300 nm, based on an enhanced surface pinning effect. E-mode GaN HEMTs having MMC structures and widths as well as via-hole-lengths of 100 nm/2 μm and 300 nm/6 μm, respectively, exhibited positive threshold voltages (V th ) of 0.79 and 0.46 V, respectively. The on-resistances of the MMC and via-hole-length structures were lower than those of typical tri-gate nanoribbon GaN HEMTs. In addition, the devices not only achieved the E-mode but also improved the power performance of the GaN HEMTs and effectively mitigated the device thermal effect. We controlled the via-hole-length sidewall surface pinning effect to obtain the E-mode GaN HEMTs. Our findings suggest that via-hole-length normally off GaN HEMTs have great potential for use in next-generation power electronics.

  9. Breaking Through the Multi-Mesa-Channel Width Limited of Normally Off GaN HEMTs Through Modulation of the Via-Hole-Length

    Science.gov (United States)

    Chien, Cheng-Yen; Wu, Wen-Hsin; You, Yao-Hong; Lin, Jun-Huei; Lee, Chia-Yu; Hsu, Wen-Ching; Kuan, Chieh-Hsiung; Lin, Ray-Ming

    2017-06-01

    We present new normally off GaN high-electron-mobility transistors (HEMTs) that overcome the typical limitations in multi-mesa-channel (MMC) width through modulation of the via-hole-length to regulate the charge neutrality screen effect. We have prepared enhancement-mode (E-mode) GaN HEMTs having widths of up to 300 nm, based on an enhanced surface pinning effect. E-mode GaN HEMTs having MMC structures and widths as well as via-hole-lengths of 100 nm/2 μm and 300 nm/6 μm, respectively, exhibited positive threshold voltages ( V th) of 0.79 and 0.46 V, respectively. The on-resistances of the MMC and via-hole-length structures were lower than those of typical tri-gate nanoribbon GaN HEMTs. In addition, the devices not only achieved the E-mode but also improved the power performance of the GaN HEMTs and effectively mitigated the device thermal effect. We controlled the via-hole-length sidewall surface pinning effect to obtain the E-mode GaN HEMTs. Our findings suggest that via-hole-length normally off GaN HEMTs have great potential for use in next-generation power electronics.

  10. Analysis and Speed Ripple Mitigation of a Space Vector Pulse Width Modulation-Based Permanent Magnet Synchronous Motor with a Particle Swarm Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Xing Liu

    2016-11-01

    Full Text Available A method is proposed for reducing speed ripple of permanent magnet synchronous motors (PMSMs controlled by space vector pulse width modulation (SVPWM. A flux graph and mathematics are used to analyze the speed ripple characteristics of the PMSM. Analysis indicates that the 6P (P refers to pole pairs of the PMSM time harmonic of rotor mechanical speed is the main harmonic component in the SVPWM control PMSM system. To reduce PMSM speed ripple, harmonics are superposed on a SVPWM reference signal. A particle swarm optimization (PSO algorithm is proposed to determine the optimal phase and multiplier coefficient of the superposed harmonics. The results of a Fourier decomposition and an optimized simulation model verified the accuracy of the analysis as well as the effectiveness of the speed ripple reduction methods, respectively.

  11. Zero-voltage DC/DC converter with asymmetric pulse-width modulation for DC micro-grid system

    Science.gov (United States)

    Lin, Bor-Ren

    2018-04-01

    This paper presents a zero-voltage switching DC/DC converter for DC micro-grid system applications. The proposed circuit includes three half-bridge circuit cells connected in primary-series and secondary-parallel in order to lessen the voltage rating of power switches and current rating of rectifier diodes. Thus, low voltage stress of power MOSFETs can be adopted for high-voltage input applications with high switching frequency operation. In order to achieve low switching losses and high circuit efficiency, asymmetric pulse-width modulation is used to turn on power switches at zero voltage. Flying capacitors are used between each circuit cell to automatically balance input split voltages. Therefore, the voltage stress of each power switch is limited at Vin/3. Finally, a prototype is constructed and experiments are provided to demonstrate the circuit performance.

  12. Effect of second harmonic in pulse-width-modulation-based DAC for feedback of digital fluxgate magnetometer

    Science.gov (United States)

    Belyayev, Serhiy; Ivchenko, Nickolay

    2018-04-01

    Digital fluxgate magnetometers employ processing of the measured pickup signal to produce the value of the compensation current. Using pulse-width modulation with filtering for digital to analog conversion is a convenient approach, but it can introduce an intrinsic source of nonlinearity, which we discuss in this design note. A code shift of one least significant bit changes the second harmonic content of the pulse train, which feeds into the pick-up signal chain despite the heavy filtering. This effect produces a code-dependent nonlinearity. This nonlinearity can be overcome by the specific design of the timing of the pulse train signal. The second harmonic is suppressed if the first and third quarters of the excitation period pulse train are repeated in the second and fourth quarters. We demonstrate this principle on a digital magnetometer, achieving a magnetometer noise level corresponding to that of the sensor itself.

  13. Three-dimensional shape profiling by out-of-focus projection of colored pulse width modulation fringe patterns.

    Science.gov (United States)

    Silva, Adriana; Flores, Jorge L; Muñoz, Antonio; Ayubi, Gastón A; Ferrari, José A

    2017-06-20

    Three-dimensional (3D) shape profiling by sinusoidal phase-shifting methods is affected by the non-linearity of the projector. To overcome this problem, the defocusing technique has become an important alternative to generate sinusoidal fringe patterns. The precision of this method depends on the binary pattern used and on the defocusing applied. To improve the defocusing technique, we propose the implementation of a color-based binary fringe patterns. The proposed technique involves the generation of colored pulse width modulation (PWM) fringe patterns, which are generated with different frequencies at the carrier signal. From an adequate selection of these frequencies, the colored PWM fringe patterns will lead to amplitude harmonics lower than the conventional PWM fringe patterns. Hence, the defocusing can decrease, and the 3D shape profiling can be more accurate. Numerical simulations and experimental results are presented as validation.

  14. Energy spectrum control for modulated proton beams

    International Nuclear Information System (INIS)

    Hsi, Wen C.; Moyers, Michael F.; Nichiporov, Dmitri; Anferov, Vladimir; Wolanski, Mark; Allgower, Chris E.; Farr, Jonathan B.; Mascia, Anthony E.; Schreuder, Andries N.

    2009-01-01

    In proton therapy delivered with range modulated beams, the energy spectrum of protons entering the delivery nozzle can affect the dose uniformity within the target region and the dose gradient around its periphery. For a cyclotron with a fixed extraction energy, a rangeshifter is used to change the energy but this produces increasing energy spreads for decreasing energies. This study investigated the magnitude of the effects of different energy spreads on dose uniformity and distal edge dose gradient and determined the limits for controlling the incident spectrum. A multilayer Faraday cup (MLFC) was calibrated against depth dose curves measured in water for nonmodulated beams with various incident spectra. Depth dose curves were measured in a water phantom and in a multilayer ionization chamber detector for modulated beams using different incident energy spreads. Some nozzle entrance energy spectra can produce unacceptable dose nonuniformities of up to ±21% over the modulated region. For modulated beams and small beam ranges, the width of the distal penumbra can vary by a factor of 2.5. When the energy spread was controlled within the defined limits, the dose nonuniformity was less than ±3%. To facilitate understanding of the results, the data were compared to the measured and Monte Carlo calculated data from a variable extraction energy synchrotron which has a narrow spectrum for all energies. Dose uniformity is only maintained within prescription limits when the energy spread is controlled. At low energies, a large spread can be beneficial for extending the energy range at which a single range modulator device can be used. An MLFC can be used as part of a feedback to provide specified energy spreads for different energies.

  15. Isolated PWM DC-AC SICAM with an active capacitive voltage clamp[Pulse Density Modulated; Pulse Width Modulation

    Energy Technology Data Exchange (ETDEWEB)

    Ljusev, P.

    2004-03-15

    In this report an isolated PWM DC-AC SICAM with an active capacitive voltage clamp is presented. AC-DC power supply is implemented in its simplest form: diode rectifier followed by a medium-size charge-storage capacitors and possibly with an EMC filter on the mains entrance. Isolation from the AC mains is achieved using a high frequency (HF) transformer, whose voltages are not audio-modulated. The latter simplifies the design and is expected to have many advantages over the approach where the transformer voltages are modulated in regards to the audio signal reference. Input stage is built as a DC-AC inverter (push-pull, half-bridge or a full-bridge) and operated with 50% duty cycle, with all the challenges to avoid transformer saturation and obtain symmetrical operation. On the secondary side the output section is implemented as rectifier+inverter AC-AC stage, i.e. a true bidirectional bridge, which operation is aimed towards amplification of the audio signal. In order to solve the problem with the commutation of the load current, a dead time between the incoming and outgoing bidirectional switch is implemented, while a capacitive voltage clamp is used to keep the induced overvoltage to reasonable levels. The energy stored in the clamping capacitor is not wasted as in the dissipative clamps, but is rather transferred back to the primary side for further processing using an auxiliary isolated single-switch converter, i.e. an active clamping technique is used. (au)

  16. Pulse width modulated push-pull driven parallel resonant converter with active free-wheel

    Science.gov (United States)

    Reass, William A.; Schrank, Louis

    2004-06-22

    An apparatus and method for high frequency alternating power generation to control kilowatts of supplied power in microseconds. The present invention includes a means for energy storage, push-pull switching means, control electronics, transformer means, resonant circuitry and means for excess energy recovery, all in electrical communication. A push-pull circuit works synchronously with a force commutated free-wheel transistor to provide current pulses to a transformer. A change in the conduction angle of the push-pull circuit changes the amount of energy coupled into the transformer's secondary oscillating circuit, thereby altering the induced secondary resonating voltage. At the end of each pulse, the force commutated free-wheel transistor causes residual excess energy in the primary circuit to be transmitted back to the storage capacitor for later use.

  17. Frequency Properties Research of Elevator Drive System with Direct Torque Control-Pulse with Modulation

    Directory of Open Access Journals (Sweden)

    A. S. Koval

    2008-01-01

    Full Text Available In the article problems of frequency properties research for electric drive system with direct torque control and pulse width modulator are described. The mathematical description of elevator is present. Simplified mathematical description of direct torque control - pulse width modulator electric drive system is shown. Transfer functions for torque and speed loops are determined. Logarithmic frequency characteristics are computed. Damping properties of elevator drive system are estimated.

  18. Pengaruh Penambahan PWM (Pulse Width Modulation Pada Generator HHO Tipe Dry Cell

    Directory of Open Access Journals (Sweden)

    Fungky Dyan Pertiwi

    2013-09-01

    Full Text Available Generator HHO memanfaatkan proses elektrolisis air agar mendapatkan gas H2. Namun, pada praktiknya pemakaian arus dari aki yang besar dan temperatur tinggi membuat bejana generator menjadi cepat rusak, sehingga dibutuhkan tambahan rangkaian elektronika PWM pada pengujian generator HHO guna mengatasi permasalahan tersebut. Penelitian menggunakan elektroda plat berjumlah 9 berdimensi 120mm 120mm, tebal 1mm dan dibatasi oleh o-ring dengan diameter 126mm, tebal 3mm. Pengujian dilakukan secara eksperimen dengan 2 kelompok yaitu kelompok control yang mana pengujian tanpa menggunakan PWM serta kelompok uji dimana pengujian menggunakan PWM dengan variasi duty cycle 30%, 50% dan 70%. Pengujian dilakukan hingga temperatur elektrolit 93oC. Hasil uji didapatkan bahwa arus, laju produksi dan efisiensi terbesar didapatkan pada pengujian tanpa PWM yang mencapai 60,6A, 6,033 10-6kg/s dan 25,69%. Namun, pada pengambilan data kedua efisiensi turun menjadi 19,74%. Penambahan PWM pada pengujian berpengaruh pada arus dan temperatur yang stabil meskipun laju produksi dan efisiensi lebih kecil daripada pengujian tanpa PWM. Pengujian dengan PWM pada duty cycle 70% menghasilkan laju produksi dan efisiensi terbesar yang mencapai 1,843 10-6 kg/s dan 15,19%.

  19. Controllable pulse width of bright similaritons in a tapered graded index diffraction decreasing waveguide

    Energy Technology Data Exchange (ETDEWEB)

    Prakash, S. Arun [Department of EEE, Anna University, Ramanathapuram 623513 (India); Malathi, V. [Department of EEE, Anna University, Regional office, Madurai (India); Mani Rajan, M. S., E-mail: senthilmanirajanofc@gmail.com [Department of Physics, Anna University, Ramanathapuram 623513 (India); Loomba, Shally [Department of Physics, Panjab University, Chandigarh 160014 (India)

    2016-03-15

    We obtain the bright similariton solutions for generalized inhomogeneous nonlinear Schrödinger equation (GINLSE) which governs the pulse propagation in a tapered graded index diffraction decreasing waveguide (DDW). The exact solutions have been worked out by employing similarity transformations which involve the mapping of the GINLSE to standard NLSE for the certain conditions of the parameters. By making use of the exact analytical solutions, we have investigated the dynamical behavior of optical similariton pairs and have suggested the methods to control them as they propagate through DDW. Moreover, pulse width of similariton is controlled through various profiles. These results are helpful to understand the similaritons in DDW and can be potentially useful for future experiments in optical communications which involve optical amplifiers and long-haul telecommunication networks.

  20. A Novel Transcranial Magnetic Stimulator Inducing Near Rectangular Pulses with Controllable Pulse Width (cTMS)

    Science.gov (United States)

    Jalinous, Reza; Lisanby, Sarah H.

    2013-01-01

    A novel transcranial magnetic stimulation (TMS) device with controllable pulse width (PW) and near rectangular pulse shape (cTMS) is described. The cTMS device uses an insulated gate bipolar transistor (IGBT) with appropriate snubbers to switch coil currents up to 7 kA, enabling PW control from 5 μs to over 100 μs. The near-rectangular induced electric field pulses use 22–34% less energy and generate 67–72% less coil heating compared to matched conventional cosine pulses. CTMS is used to stimulate rhesus monkey motor cortex in vivo with PWs of 20 to 100 μs, demonstrating the expected decrease of threshold pulse amplitude with increasing PW. The technological solutions used in the cTMS prototype can expand functionality, and reduce power consumption and coil heating in TMS, enhancing its research and therapeutic applications. PMID:18232369

  1. Virtual-vector-based space vector pulse width modulation of the DC-AC multilevel-clamped multilevel converter (MLC2)

    DEFF Research Database (Denmark)

    Rodriguez, Pedro; Busquets-Monge, Sergio; Blaabjerg, Frede

    2011-01-01

    This work presents the development of the space vector pulse width modulation (SVPWM) of a new multi-level converter topology. First, the proposed converter and its natural space vector diagram are presented. Secondly, a modified space vector diagram based on the virtual-vectors technique is show...

  2. Analyzing the effectiveness of flare dispensing programs against pulse width modulation seekers using self-organizing maps

    Science.gov (United States)

    Şahingil, Mehmet C.; Aslan, Murat Š.

    2013-10-01

    Infrared guided missile seekers utilizing pulse width modulation in target tracking is one of the threats against air platforms. To be able to achieve a "soft-kill" protection of own platform against these type of threats, one needs to examine carefully the seeker operating principle with its special electronic counter-counter measure (ECCM) capability. One of the cost-effective ways of soft kill protection is to use flare decoys in accordance with an optimized dispensing program. Such an optimization requires a good understanding of the threat seeker, capabilities of the air platform and engagement scenario information between them. Modeling and simulation is very powerful tool to achieve a valuable insight and understand the underlying phenomenology. A careful interpretation of simulation results is crucial to infer valuable conclusions from the data. In such an interpretation there are lots of factors (features) which affect the results. Therefore, powerful statistical tools and pattern recognition algorithms are of special interest in the analysis. In this paper, we show how self-organizing maps (SOMs), which is one of those powerful tools, can be used in analyzing the effectiveness of various flare dispensing programs against a PWM seeker. We perform several Monte Carlo runs for a typical engagement scenario in a MATLAB-based simulation environment. In each run, we randomly change the flare dispending program and obtain corresponding class: "successful" or "unsuccessful", depending on whether the corresponding flare dispensing program deceives the seeker or not, respectively. Then, in the analysis phase, we use SOMs to interpret and visualize the results.

  3. Can cost make a difference dosimetrically? Volumetric modulated arc therapy study for multileaf collimators of various widths for head and neck and prostate cancers

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Jong-Han, E-mail: jonghanho@gmail.com; Hagler, Shane; Lujano, Carrie; Seng, Sopaul; Starks, Christine; Perrin, Kelly; Turner, Lehendrick; Court, Laurence

    2017-04-01

    Cancer is a global health issue that disproportionately kills based on stage of disease, cellular pathology, and genetics, to name a few. Another variable to consider in this ongoing fight is treatment machine complexity that leads to elevated development and purchasing cost, leading to a reduced use. Reducing the complexity (in hopes of lowering costs) would benefit underdeveloped, low- and middle-income countries by introducing newer treatment technology, as their currently accepted standards do not meet standards of more advanced, developed countries. In this study, unilateral head and neck (H&N), and prostate cases using volumetric modulated arc therapy (VMAT) were tested with multiple segment widths of 5, 10, 15, and 20 mm to create treatable plans. Pinnacle 9.10v was used for planning purposes. A total of 12 cases were planned with varying multileaf collimator (MLC) widths. Treatment plans were evaluated retrospectively. Results show that altering the MLC widths from 5 through 20 mm produces both comparable and treatable plans up to 99% and 98% target coverage for H&N and prostate, respectively, albeit clinically significant hot spots were shown to increase with increasing segment width. Furthermore, the results show that increasing widths can produce comparable treatment plans as measured against our current Food and Drug Administration (FDA)–approved treatment devices—leading to an increase in treatment efficacy in economically underdeveloped countries.

  4. Alluvial cover controlling the width, slope and sinuosity of bedrock channels

    Science.gov (United States)

    Turowski, Jens Martin

    2018-02-01

    Bedrock channel slope and width are important parameters for setting bedload transport capacity and for stream-profile inversion to obtain tectonics information. Channel width and slope development are closely related to the problem of bedrock channel sinuosity. It is therefore likely that observations on bedrock channel meandering yields insights into the development of channel width and slope. Active meandering occurs when the bedrock channel walls are eroded, which also drives channel widening. Further, for a given drop in elevation, the more sinuous a channel is, the lower is its channel bed slope in comparison to a straight channel. It can thus be expected that studies of bedrock channel meandering give insights into width and slope adjustment and vice versa. The mechanisms by which bedrock channels actively meander have been debated since the beginning of modern geomorphic research in the 19th century, but a final consensus has not been reached. It has long been argued that whether a bedrock channel meanders actively or not is determined by the availability of sediment relative to transport capacity, a notion that has also been demonstrated in laboratory experiments. Here, this idea is taken up by postulating that the rate of change of both width and sinuosity over time is dependent on bed cover only. Based on the physics of erosion by bedload impacts, a scaling argument is developed to link bedrock channel width, slope and sinuosity to sediment supply, discharge and erodibility. This simple model built on sediment-flux-driven bedrock erosion concepts yields the observed scaling relationships of channel width and slope with discharge and erosion rate. Further, it explains why sinuosity evolves to a steady-state value and predicts the observed relations between sinuosity, erodibility and storm frequency, as has been observed for meandering bedrock rivers on Pacific Arc islands.

  5. Alluvial cover controlling the width, slope and sinuosity of bedrock channels

    Directory of Open Access Journals (Sweden)

    J. M. Turowski

    2018-02-01

    Full Text Available Bedrock channel slope and width are important parameters for setting bedload transport capacity and for stream-profile inversion to obtain tectonics information. Channel width and slope development are closely related to the problem of bedrock channel sinuosity. It is therefore likely that observations on bedrock channel meandering yields insights into the development of channel width and slope. Active meandering occurs when the bedrock channel walls are eroded, which also drives channel widening. Further, for a given drop in elevation, the more sinuous a channel is, the lower is its channel bed slope in comparison to a straight channel. It can thus be expected that studies of bedrock channel meandering give insights into width and slope adjustment and vice versa. The mechanisms by which bedrock channels actively meander have been debated since the beginning of modern geomorphic research in the 19th century, but a final consensus has not been reached. It has long been argued that whether a bedrock channel meanders actively or not is determined by the availability of sediment relative to transport capacity, a notion that has also been demonstrated in laboratory experiments. Here, this idea is taken up by postulating that the rate of change of both width and sinuosity over time is dependent on bed cover only. Based on the physics of erosion by bedload impacts, a scaling argument is developed to link bedrock channel width, slope and sinuosity to sediment supply, discharge and erodibility. This simple model built on sediment-flux-driven bedrock erosion concepts yields the observed scaling relationships of channel width and slope with discharge and erosion rate. Further, it explains why sinuosity evolves to a steady-state value and predicts the observed relations between sinuosity, erodibility and storm frequency, as has been observed for meandering bedrock rivers on Pacific Arc islands.

  6. Active control of annular flow-induced vibration of axisymmetric elastic beam by the local gap width control

    International Nuclear Information System (INIS)

    Takada, Shoji; Shintani, Atsuhiko; Ito, Tomohiro; Fujita, Katsuhisa

    2011-01-01

    Flow-induced vibration may occur in the structures such as elastic beams subjected to annular flow in the narrow passage. Once the flow-induced vibration occurs, vibration amplitude becomes larger, consequently it causes a lot of troubles such as fatigue or failure in mechanical structures. In this paper, for the purpose to avoid these troubles, the active control of vibration of an axisymmetric elastic beam subjected to annular flow is investigated. An air-pressured actuator is attached on the surface of the circular cylinder for the vibrational control. As the shape of the actuator changes by control, the gap width in narrow passage changes, which causes the change of the fluid pressure. Therefore, the vibration of the fluid-structure coupled system can be suppressed. The fluid-structure coupled equation based on the Euler-Bernoulli type of partial differential equation and the Navier-Stokes equations is analytically derived including control terms. By applying the optimal control law to the coupled system, the unstable behavior is stabilized. The stability of the coupled system is investigated by eigenvalue analyses of controlled coupled equations. Numerical simulations are performed to investigate the efficiency of the proposed control method. (author)

  7. Controllable Pulse Frequency and Width System for Pulsing and Modulating Fast-Neutron Core Assemblies; Systeme a Frequence et Largeur d'Impulsions Ajustables Permettant la Pulsation et la Modulation de Milieux Multipliants Sous-Critiques a Neutrons Rapides; Sistema reguliruemykh chastoty i shiriny impul'sa, dayushaya impul's i modulyatsiyu razmnozhayushchikh sred na bystrykh nejtronakh; Sistema de Frecuencia y Amplitud de Impulso Ajustables, para Pulsar y Modular

    Energy Technology Data Exchange (ETDEWEB)

    Duquesne, M.; Lyon, F.; Schmitt, A. [Association Euratom-CEA-SECNR (France); Nucleaires de Cadarache, Centre d' Etudes [France; Gerbier, R. [Laboratoire des Accelerateurs - CEN de Grenoble (France); Nucleaires de Cadarache, Centre d' Etudes [France

    1965-10-15

    The authors describe a system for producing neutron bursts of independently controllable width and frequency. The rise and quenching times of these bursts are of the order of a few nanoseconds. The system is applied to high-frequency pulsed and modulated experiments. Rapidly quenched neutron bursts are produced by deflection of a pure deuteron beam which has previously been accelerated and sorted. Ions other than atomic deuterons are removed after acceleration in a 10 Degree-Sign magnetic sorting field. Consideration is also being given to a pre-acceleration sorting system offering the advantage of reduced bulk. The deuteron beam passes through the space between two plates where there is normally an electrostatic field which deflects the beam onto the surfaces of a diaphragm. Application of a very high potential pulse to the first plate cancels the field and thus brings the beam rapidly onto the neutron-producing target (beginning of the burst). The second plate then receives a pulse of the same type which restores the field and removes the beam from the target (end of the burst). The pulse rise time is of the order of 10 ns; disappearance from the target is faster. The duration of the burst can be controlled as required within reasonable limits by suitably increasing the interval between the two pulses. In some cases ion transit time in the plates is not negligible in relation to the duration of the step applied to them. In such cases, one of the plates is replaced by a travelling wave line to which the two pulses are applied successively. The potential pulse thus accompanies the deuteron cluster producing the burst. The burst times can thus be reduced below 4 ns. The first stages of the voltage step generators are transistorized. The output tubes are sealed-disc valves providing a 1500-V step in a few nanoseconds. A 50-MHz double tetrode is employed for pulses for the delay line. A detection system comprises a scintillator-photomultiplier device incorporating a

  8. PLC control of 50 MW klystron modulators

    International Nuclear Information System (INIS)

    Shang Lei; Liu Gongfa; Chen Liping; Lu Yeming; Hong Jun; Zhang Yi; Zhao Feng

    2004-01-01

    Upgrade project of the 50 MW klystron modulators of Hefei Light Source (HLS) was firstly introduced. PLC control system of modulators was employed to replace the old control and monitor system, which was based on relay logic circuit and manual operation method. the PLC system becomes a sub system of the new EPICS control system of HLS. Constant-current, switch-mode and high voltage power supplies were adopted to replace the old 50 Hz power supplies. The technology of modulators was improved and operation was more reliable. The design method, hardware and software of PLC control of modulators were described and the performance was presented. (authors)

  9. ATLAS ITk short-strip stave prototype module with integrated DCDC powering and control

    CERN Document Server

    AUTHOR|(SzGeCERN)397167; The ATLAS collaboration

    2017-01-01

    During the Phase II upgrade, the ATLAS detector at the LHC will be upgraded with a new Inner Tracker (ITk) detector. The ITk prototype barrel module design has adopted an integrated low mass assembly featuring single-sided flexible circuits, with readout ASICs, glued to the silicon strip sensor. Further integration has been achieved by the attachment of module DCDC powering, a HV sensor biasing switch and autonomous monitoring and control to the sensor. This low mass integrated module approach benefits further in a reduced width stave structure to which the modules are attached. The results of preliminary electrical tests of such an integrated module are presented.

  10. Monetary rewards modulate inhibitory control

    Directory of Open Access Journals (Sweden)

    Paula Marcela Herrera

    2014-05-01

    Full Text Available The ability to override a dominant response, often referred to as behavioural inhibiton, is considered a key element of executive cognition. Poor behavioural inhibition is a defining characteristic of several neurological and psychiatric populations. Recently, there has been increasing interest in the motivational dimension of behavioural inhibition, with some experiments incorporating emotional contingencies in classical inhibitory paradigms such as the Go/Nogo and Stop Signal Tasks. Several studies have reported a positive modulatory effect of reward on the performance of such tasks in pathological conditions such as substance abuse, pathological gambling, and ADHD. However, experiments that directly investigate the modulatory effects of reward magnitudes on the performance of inhibitory paradigms are rare and consequently, little is known about the finer grained relationship between motivation and self-control. Here, we probed the effect of reward and reward magnitude on behavioural inhibition using two modified version of the widely used Stop Signal Task. The first task compared no reward with reward, whilst the other compared two different reward magnitudes. The reward magnitude effect was confirmed by the second study, whereas it was less compelling in the first study, possibly due to the effect of having no reward in some conditions. In addition, our results showed a kick start effect over global performance measures. More specifically, there was a long lasting improvement in performance throughout the task, when participants received the highest reward magnitudes at the beginning of the protocol. These results demonstrate that individuals’ behavioural inhibition capacities are dynamic not static because they are modulated by the reward magnitude and initial reward history of the task at hand.

  11. Microprocessor-controlled CAMAC data link module

    International Nuclear Information System (INIS)

    Potter, J.M.

    1978-05-01

    Communication between the central control computer and remote, satellite data-acquisition/control stations at the Clinton P. Anderson Meson Physics Facility (LAMPF) is presently accomplished through the use of CAMAC-based Data Link modules. With the advent of the microprocessor, a new philosophy for digital data communications has evolved. Data Link modules containing microprocessor controllers provide link management and communication network protocol through algorithms executed in the Data Link microprocessor. 13 figures

  12. Bag-like contaminant control work module

    International Nuclear Information System (INIS)

    Buchanan, H.; Jacobson, E.B.

    1982-01-01

    A bag-like contaminant control work module is formed from a flexible impervious membrane which is inflated inside of an enclosed workspace to protect workers in the module from contaminants. The workspace, such as in a nuclear power steam generator, has a portal or manway opening into the workspace into which the module is secured by a module passageway. The module includes one or more glove boxes, in which the workers perform their assigned tasks after passing through the passageway and portal. The module includes one or more absolute filters allowing passage of air flow through the module passageway and into the workspace only through the filters. The module may include an auxiliary passageway secured to the outside of the module passageway and also secured in the portal opening and through which items can be passed back and forth to the worker in the glove box from outside the portal. The module is invertible so that it can be pulled out of the workspace trapping all the contaminants therein and disposed of without handling the contaminants

  13. The Robust Control Mixer Module Method for Control Reconfiguration

    DEFF Research Database (Denmark)

    Yang, Z.; Blanke, M.

    1999-01-01

    into a LTI dynamical system, and furthermore multiple dynamical control mixer modules can be employed in our consideration. The H_{\\infty} control theory is used for the analysis and design of the robust control mixer modules. Finally, one practical robot arm system as benchmark is used to test the proposed......The control mixer concept is efficient in improving an ordinary control system into a fault tolerant one, especially for these control systems of which the real-time and on-line redesign of the control laws is very difficult. In order to consider the stability, performance and robustness...... of the reconfigurated system simultaneously, and to deal with a more general controller reconfiguration than the static feedback mechanism by using the control mixer approach, the robust control mixer module method is proposed in this paper. The form of the control mixer module extends from a static gain matrix...

  14. Effect of MLC Leaf Width and PTV Margin on the Treatment Planning of Intensity-Modulated Stereotactic Radiosurgery (IMSRS) or Radiotherapy (IMSRT)

    International Nuclear Information System (INIS)

    Chang Jenghwa; Yenice, Kamil M.; Jiang Kailiu; Hunt, Margie; Narayana, Ashwatha

    2009-01-01

    We studied the effect of MLC (multileaf collimator) leaf width and PTV (planning target volume) margin on treatment planning of intensity modulated stereotactic radiosurgery (IMSRS) or radiotherapy (IMSRT). Twelve patients previously treated with IMSRS/IMSRT were retrospectively planned with 5- and 3-mm MLC leaf widths and 3- and 2-mm PTV margins using the already contoured clinical target volume and critical structures. The same beam arrangement, planning parameters, and optimization method were used in each of the 4 plans for a given patient. Each plan was normalized so that the prescription dose covered at least 99% of the PTV. Plan indices - D mean (mean dose), conformity index (CI), V 70 (volume receiving ≥ 70% of the prescription dose), and V 50 (volume receiving ≥ 50% of the prescription dose) - were calculated from the dose-volume histograms (DVHs) of the PTV, normal tissue, and organs at risk (OARs). Hypothesis testing was performed on the mean ratios of plan indices to determine the statistical significance of the relative differences. The PTV was well covered for all plans, as no significant differences were observed for D 95 , V 95 , D max , D min , and D mean of the PTV. The irradiated volume was ∼23% smaller when 2-mm instead of 3-mm PTV margin was used, but it was only reduced by ∼6% when the MLC leaf width was reduced from 5 mm to 3 mm. For normal tissue and brainstem, V 70 , V 50 , and D mean were reduced more effectively by a decrease in MLC width, while D mean of optic nerve and chiasm were more sensitive to a change in PTV margin. The DVH statistics for the PTV and normal structures from the treatment plan with 5-mm MLC and 2-mm PTV margin were equal to those with 3-mm MLC and 3-mm PTV margin. PTV margin reduction is more effective in sparing the normal tissue and OARs than a reduction in MLC leaf width. For IMSRS, where highly accurate setup and small PTV margins are routinely employed, the use of 5-mm MLC is therefore less desirable.

  15. Trainer module for security control center operations

    International Nuclear Information System (INIS)

    Bernard, E.A.

    1982-01-01

    An operator trainer module has been developed to be used with the security control center equipment to be installed as part of a safeguards physical protection system. The module is designed to provide improved training and testing capabilities for control center operators through the use of simulations for perimeter equipment operations. Operators, through the trainer module, can be challenged with a variety of realistic situations which require responsive action identical to that needed in an actual system. This permits a consistent evaluation and confirmation of operator capabilities prior to assignment as an operator and allows for periodic retesting to verify that adequate performance levels are maintained

  16. High-speed three-dimensional shape measurement for dynamic scenes using bi-frequency tripolar pulse-width-modulation fringe projection

    Science.gov (United States)

    Zuo, Chao; Chen, Qian; Gu, Guohua; Feng, Shijie; Feng, Fangxiaoyu; Li, Rubin; Shen, Guochen

    2013-08-01

    This paper introduces a high-speed three-dimensional (3-D) shape measurement technique for dynamic scenes by using bi-frequency tripolar pulse-width-modulation (TPWM) fringe projection. Two wrapped phase maps with different wavelengths can be obtained simultaneously by our bi-frequency phase-shifting algorithm. Then the two phase maps are unwrapped using a simple look-up-table based number-theoretical approach. To guarantee the robustness of phase unwrapping as well as the high sinusoidality of projected patterns, TPWM technique is employed to generate ideal fringe patterns with slight defocus. We detailed our technique, including its principle, pattern design, and system setup. Several experiments on dynamic scenes were performed, verifying that our method can achieve a speed of 1250 frames per second for fast, dense, and accurate 3-D measurements.

  17. Energy Efficiency of Induction Motors Running Off Frequency Converters with Pulse-Width Voltage Modulation{sup 1}

    Energy Technology Data Exchange (ETDEWEB)

    Shvetsov, N. K., E-mail: elmash@em.ispu.ru [V. I. Lenin Ivanovo State Power University (Russian Federation)

    2016-11-15

    The results of calculations of the increase in losses in an induction motor with frequency control and different forms of the supply voltage are presented. The calculations were performed by an analytic method based on harmonic analysis of the supply voltage as well as numerical calculation of the electromagnetic processes by the finite-element method.

  18. Effects of interventions on normalizing step width during self-paced dual-belt treadmill walking with virtual reality, a randomised controlled trial.

    Science.gov (United States)

    Oude Lansink, I L B; van Kouwenhove, L; Dijkstra, P U; Postema, K; Hijmans, J M

    2017-10-01

    Step width is increased during dual-belt treadmill walking, in self-paced mode with virtual reality. Generally a familiarization period is thought to be necessary to normalize step width. The aim of this randomised study was to analyze the effects of two interventions on step width, to reduce the familiarization period. We used the GRAIL (Gait Real-time Analysis Interactive Lab), a dual-belt treadmill with virtual reality in the self-paced mode. Thirty healthy young adults were randomly allocated to three groups and asked to walk at their preferred speed for 5min. In the first session, the control-group received no intervention, the 'walk-on-the-line'-group was instructed to walk on a line, projected on the between-belt gap of the treadmill and the feedback-group received feedback about their current step width and were asked to reduce it. Interventions started after 1min and lasted 1min. During the second session, 7-10days later, no interventions were given. Linear mixed modeling showed that interventions did not have an effect on step width after the intervention period in session 1. Initial step width (second 30s) of session 1 was larger than initial step width of session 2. Step width normalized after 2min and variation in step width stabilized after 1min. Interventions do not reduce step width after intervention period. A 2-min familiarization period is sufficient to normalize and stabilize step width, in healthy young adults, regardless of interventions. A standardized intervention to normalize step width is not necessary. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Bifurcation and Chaos in a Pulse Width modulation controlled Buck Converter

    DEFF Research Database (Denmark)

    Kocewiak, Lukasz; Bak, Claus Leth; Munk-Nielsen, Stig

    2007-01-01

    by a system of piecewise-smooth nonautonomous differential equations. The research are focused on chaotic oscillations analysis and analytical search for bifurcations dependent on parameter. The most frequent route to chaos by the period doubling is observed in the second order DC-DC buck converter. Other...... bifurcations as a complex behaviour in power electronic system evidence are also described. In order to verify theoretical study the experimental DC-DC buck converter was build. The results obtained from three sources were presented and compared. A very good agreement between theory and experiment was observed....

  20. Pulse Width Modulator Controller Design for a Brushless DC Motor Position Servo.

    Science.gov (United States)

    1987-06-01

    REQC1,REQC2, lAB, ZEC , ICA, 4. + PVAO, Fy5, PVCO,NODE,TRIG1,TRIG2,TRIG3 ,TRIG4, + TRIG5,TRIGS,RA,PLUGVAIMD,VBIND,VCIND) c call TCONST(ICQl, .75-SWl...DC Motors, Master’s Thesis, Naval Postgraduate School, Monterey, Ca., September 1984. 2. MacMillan, Peter N., A CSMP Commutation Model for .’. Design

  1. Real-time microscopic 3D shape measurement based on optimized pulse-width-modulation binary fringe projection

    Science.gov (United States)

    Hu, Yan; Chen, Qian; Feng, Shijie; Tao, Tianyang; Li, Hui; Zuo, Chao

    2017-07-01

    In recent years, tremendous progress has been made in 3D measurement techniques, contributing to the realization of faster and more accurate 3D measurement. As a representative of these techniques, fringe projection profilometry (FPP) has become a commonly used method for real-time 3D measurement, such as real-time quality control and online inspection. To date, most related research has been concerned with macroscopic 3D measurement, but microscopic 3D measurement, especially real-time microscopic 3D measurement, is rarely reported. However, microscopic 3D measurement plays an important role in 3D metrology and is indispensable in some applications in measuring micro scale objects like the accurate metrology of MEMS components of the final devices to ensure their proper performance. In this paper, we proposed a method which effectively combines optimized binary structured patterns with a number-theoretical phase unwrapping algorithm to realize real-time microscopic 3D measurement. A slight defocusing of our optimized binary patterns can considerably alleviate the measurement error based on four-step phase-shifting FPP, providing the binary patterns with a comparable performance to ideal sinusoidal patterns. The static measurement accuracy can reach 8 μm, and the experimental results of a vibrating earphone diaphragm reveal that our system can successfully realize real-time 3D measurement of 120 frames per second (FPS) with a measurement range of 8~\\text{mm}× 6~\\text{mm} in lateral and 8 mm in depth.

  2. Rapid fabrication method of a microneedle mold with controllable needle height and width.

    Science.gov (United States)

    Lin, Yen-Heng; Lee, I-Chi; Hsu, Wei-Chieh; Hsu, Ching-Hong; Chang, Kai-Ping; Gao, Shao-Syuan

    2016-10-01

    The main issue of transdermal drug delivery is that macromolecular drugs cannot diffuse through the stratum corneum of skin. Many studies have pursued micro-sized needles encapsulated with drugs to overcome this problem, as these needles can pierce the stratum corneum and allow drugs to enter the circulatory system of the human body. However, most microneedle fabrication processes are time-consuming and require expensive equipment. In this study, we demonstrate a rapid method for fabricating a microneedle mold using drawing lithography and a UV-cured resin. The mold was filled with a water-soluble material, polyvinylpyrrolidone (PVP), which was then demolded to produce a water-soluble microneedle array. The results of an in vitro skin insertion test using PVP microneedles and pig ear skin demonstrated the feasibility of the microneedle mold. In addition, by controlling the viscosity of the UV-cured resin through various heat treatments, microneedles with different heights and aspect ratios were produced. Compared with other methods, this technology significantly simplifies and accelerates the mold fabrication process. In addition, the required equipment is relatively simple and inexpensive. Through this technology, we can rapidly fabricate microneedle molds with controllable dimensions for various applications.

  3. Serotonergic modulation of spinal motor control

    DEFF Research Database (Denmark)

    Perrier, Jean-Francois Marie; Cotel, Florence

    2015-01-01

    Serotonin (5-HT) is a monoamine that powerfully modulates spinal motor control by acting on intrasynaptic and extrasynaptic receptors. Here we review the diversity of 5-HT actions on locomotor and motoneuronal activities. Two approaches have been used on in vitro spinal cord preparations: either...

  4. Control module and module for priority set-up for the CAMAC universal branch driver

    International Nuclear Information System (INIS)

    Nguen Fuk; Smirnov, V.A.

    1976-01-01

    Control module of BKD-871 universal branch driver operates as a controller in the control crate. This module performs synchronous data transmission to (from) the computer and shapes time signals for A-type controllers. The following regimes of data block transmission may be organized with the help of the control module: address scanning regime; repeated reference regime; stop regime. A priority driving module is required for organization of simultaneous operation from several control sources

  5. Study on Design of Control Module and Fuzzy Control System

    International Nuclear Information System (INIS)

    Lee, Chang Kyu; Sohn, Chang Ho; Kim, Jung Seon; Kim, Min Kyu

    2005-01-01

    Performance of control unit is improved by introduction of fuzzy control theory and compensation for input of control unit as FLC(Fuzzy Logic Controller). Here, FLC drives thermal control system by linguistic rule-base. Hence, In case of using compensative PID control unit, it doesn't need to revise or compensate for PID control unit. Consequently, this study shows proof that control system which implements H/W module and then uses fuzzy algorism in this system is stable and has reliable performance

  6. Glass frit bonding with controlled width and height using a two-step wet silicon etching procedure

    Science.gov (United States)

    Yifang, Liu; Daner, Chen; Liwei, Lin; Gaofeng, Zheng; Jianyi, Zheng; Lingyun, Wang; Daoheng, Sun

    2016-03-01

    A simple and versatile two-step silicon wet etching technique for the control of the width and height of the glass frit bonding layer has been developed to improve bonding strength and reliability in wafer-level microelectromechanical systems (MEMS) packaging processes. The height of the glass frit bonding layer is set by the design of a vertical reference wall which regulates the distance between the silicon wafer and the encapsulation capping substrate. On the other hand, the width of the bonding layer is constrained between two micro grooves which are used to accommodate the spillages of extra glass frit during the bonding process. An optimized thermal bonding process, including the formation of glass liquid, removal of gas bubbles under vacuum and the filling of voids under normal atmospheric condition has been developed to suppress the formation of the bubbles/voids. The stencil printing and pre-sintering processes for the glass frit have been characterized before the thermal bonding process under different magnitudes of bonding pressure. The bonding gap thickness is found to be equal to the height of the reference wall of 10 μm in the prototype design. The bubbles/voids are found to be suppressed effectively and the bonding strength increases from 10.2 to 19.1 MPa as compared with a conventional thermal annealing process in air. Experimentally, prototype samples are measured to have passed the high hermetic sealing leakage tests of 5  ×  10-8 atm cc s-1.

  7. Pulse-Width Modulation Pre Emphasis applied in a Wireline Transmitter, achieving 33dB Loss Compensation at 5-Gb/s in 0.13-μm CMOS

    NARCIS (Netherlands)

    Schrader, J.H.R.; Klumperink, Eric A.M.; Visschers, J.L.; Nauta, Bram

    2006-01-01

    Abstract—A transmitter pre-emphasis technique for copper cable equalization is presented that is based on pulse-width modulation (PWM). This technique is an alternative to the usual 2-tap symbol-spaced FIR (SSF) pre-emphasis. The technique uses timing resolution instead of amplitude resolution to

  8. Fuzzy Logic Controlled Solar Module for Driving Three- Phase Induction Motor

    Science.gov (United States)

    Afiqah Zainal, Nurul; Sooi Tat, Chan; Ajisman

    2016-02-01

    Renewable energy produced by solar module gives advantages for generated three- phase induction motor in remote area. But, solar module's ou tput is uncertain and complex. Fuzzy logic controller is one of controllers that can handle non-linear system and maximum power of solar module. Fuzzy logic controller used for Maximum Power Point Tracking (MPPT) technique to control Pulse-Width Modulation (PWM) for switching power electronics circuit. DC-DC boost converter used to boost up photovoltaic voltage to desired output and supply voltage source inverter which controlled by three-phase PWM generated by microcontroller. IGBT switched Voltage source inverter (VSI) produced alternating current (AC) voltage from direct current (DC) source to control speed of three-phase induction motor from boost converter output. Results showed that, the output power of solar module is optimized and controlled by using fuzzy logic controller. Besides that, the three-phase induction motor can be drive and control using VSI switching by the PWM signal generated by the fuzzy logic controller. This concluded that the non-linear system can be controlled and used in driving three-phase induction motor.

  9. Fuzzy Logic Controlled Solar Module for Driving Three- Phase Induction Motor

    International Nuclear Information System (INIS)

    Zainal, Nurul Afiqah; Tat, Chan Sooi; Ajisman

    2016-01-01

    Renewable energy produced by solar module gives advantages for generated three- phase induction motor in remote area. But, solar module's output is uncertain and complex. Fuzzy logic controller is one of controllers that can handle non-linear system and maximum power of solar module. Fuzzy logic controller used for Maximum Power Point Tracking (MPPT) technique to control Pulse-Width Modulation (PWM) for switching power electronics circuit. DC-DC boost converter used to boost up photovoltaic voltage to desired output and supply voltage source inverter which controlled by three-phase PWM generated by microcontroller. IGBT switched Voltage source inverter (VSI) produced alternating current (AC) voltage from direct current (DC) source to control speed of three-phase induction motor from boost converter output. Results showed that, the output power of solar module is optimized and controlled by using fuzzy logic controller. Besides that, the three-phase induction motor can be drive and control using VSI switching by the PWM signal generated by the fuzzy logic controller. This concluded that the non-linear system can be controlled and used in driving three-phase induction motor. (paper)

  10. Interference Control Modulations Over Conscious Perception

    Directory of Open Access Journals (Sweden)

    Itsaso Colás

    2017-05-01

    Full Text Available The relation between attention and consciousness has been a controversial topic over the last decade. Although there seems to be an agreement on their distinction at the functional level, no consensus has been reached about attentional processes being or not necessary for conscious perception. Previous studies have explored the relation of alerting and orienting systems of attention and conscious perception, but the impact of the anterior executive attention system on conscious access remains unexplored. In the present study, we investigated the behavioral interaction between executive attention and conscious perception, testing control mechanisms both at stimulus-level representation and after error commission. We presented a classical Stroop task, manipulating the proportion of congruent and incongruent trials, and analyzed the effect of reactive and proactive control on the conscious perception of near-threshold stimuli. Reactive control elicited under high proportion congruent conditions influenced participants’ decision criterion, whereas proactive control elicited under low proportion congruent conditions was ineffective in modulating conscious perception. In addition, error commission affected both perceptual sensitivity to detect near-threshold information and response criterion. These results suggest that reactivation of task goals through reactive control strategies in conflict situations impacts decision stages of conscious processing, whereas interference control elicited by error commission impacts both perceptual sensitivity and decision stages of conscious processing. We discuss the implications of our results for the gateway hypothesis about attention and consciousness, as they showed that interference control (both at stimulus-level representation and after error commission can modulate the conscious access of near-threshold stimuli.

  11. Microeconomics of 300-mm process module control

    Science.gov (United States)

    Monahan, Kevin M.; Chatterjee, Arun K.; Falessi, Georges; Levy, Ady; Stoller, Meryl D.

    2001-08-01

    Simple microeconomic models that directly link metrology, yield, and profitability are rare or non-existent. In this work, we validate and apply such a model. Using a small number of input parameters, we explain current yield management practices in 200 mm factories. The model is then used to extrapolate requirements for 300 mm factories, including the impact of simultaneous technology transitions to 130nm lithography and integrated metrology. To support our conclusions, we use examples relevant to factory-wide photo module control.

  12. Fine mapping TaFLW1, a major QTL controlling flag leaf width in bread wheat (Triticum aestivum L.).

    Science.gov (United States)

    Xue, Shulin; Xu, Feng; Li, Guoqiang; Zhou, Yan; Lin, Musen; Gao, Zhongxia; Su, Xiuhong; Xu, Xiaowu; Jiang, Ge; Zhang, Shuang; Jia, Haiyan; Kong, Zhongxin; Zhang, Lixia; Ma, Zhengqiang

    2013-08-01

    Flag leaf width (FLW) is directly related to photosynthetic capacity and yield potential in wheat. In a previous study, Qflw.nau-5A controlling FLW was detected on chromosome 5A in the interval possessing Fhb5 for type I Fusarium head blight (FHB) resistance using a recombinant inbred line population derived from Nanda2419 × Wangshuibai. Qflw.nau-5A near-isogenic line (NIL) with the background of Mianyang 99-323 and PH691 was developed and evaluated. FLW inheritance was investigated using two F2 populations developed from crossing the Qflw.nau-5A NILs with their recurrent parents. One hundred ten and 28 recombinants, which included 10 and 5 types of recombinants, were identified from 2816 F2 plants with Mianyang 99-323 background and 1277 F2 plants with PH691 background, respectively, and phenotyped in field trials for FLW and type I FHB resistance. Deletion bin mapping was applied to physically map Qflw.nau-5A. The introduction of Wangshuibai Qflw.nau-5A allele reduced the FLW up to 3 mm. In the F2 populations, Qflw.nau-5A was inherited like a semi-dominant gene, and was therefore designated as TaFLW1. The FLW of the recombinant lines displayed a distinct two-peak distribution. Recombinants with wider leaves commonly have Mianyang 99-323 or PH691 chromatin in the 0.2 cM Xwmc492-Xwmc752 interval that resided in the 5AL12-0.35-0.57 deletion bin, and recombinants with narrow leaves were Wangshuibai genotype in this interval. Phenotypic recombination between FLW and type I FHB resistance was identified, implying TaFLW1 was in close linkage with Fhb5. These results should aid wheat breeders to break the linkage drag through marker-assisted selection and assist in the map-based cloning of TaFLW1.

  13. Stressor controllability modulates fear extinction in humans

    Science.gov (United States)

    Hartley, Catherine A.; Gorun, Alyson; Reddan, Marianne C.; Ramirez, Franchesca; Phelps, Elizabeth A.

    2014-01-01

    Traumatic events are proposed to play a role in the development of anxiety disorders, however not all individuals exposed to extreme stress experience a pathological increase in fear. Recent studies in animal models suggest that the degree to which one is able to control an aversive experience is a critical factor determining its behavioral consequences. In this study, we examined whether stressor controllability modulates subsequent conditioned fear expression in humans. Participants were randomly assigned to an escapable stressor condition, a yoked inescapable stressor condition, or a control condition involving no stress exposure. One week later, all participants underwent fear conditioning, fear extinction, and a test of extinction retrieval the following day. Participants exposed to inescapable stress showed impaired fear extinction learning and increased fear expression the following day. In contrast, escapable stress improved fear extinction and prevented the spontaneous recovery of fear. Consistent with the bidirectional controllability effects previously reported in animal models, these results suggest that one's degree of control over aversive experiences may be an important factor influencing the development of psychological resilience or vulnerability in humans. PMID:24333646

  14. Development of control system for the electron gun modulator

    International Nuclear Information System (INIS)

    Hasegawa, T.; Nagasawa, S.; Kobayashi, T.; Hanaki, H.

    2004-01-01

    We have been developing a compact and inexpensive electron gun modulator for the SPring-8 Linac. The modulator was redesigned and manufactured to achieve good maintainability and high controllability. A control system of the modulator and a high voltage station is composed mainly of PLCs as a controller and touch panels for human interface. This simplified construction will result in enhancement of its reliability. The rich graphical user interface on the touch panels greatly extends the function of the control system. (author)

  15. Sub-15 nm nano-pattern generation by spacer width control for high density precisely positioned self-assembled device nanomanufacturing

    KAUST Repository

    Rojas, Jhonathan Prieto; Hussain, Muhammad Mustafa

    2012-01-01

    We present a conventional micro-fabrication based thin film vertical sidewall (spacer) width controlled nano-gap fabrication process to create arrays of nanopatterns for high density precisely positioned self-assembled nanoelectronics device integration. We have used conventional optical lithography to create base structures and then silicon nitride (Si 3N4) based spacer formation via reactive ion etching. Control of Si3N4 thickness provides accurate control of vertical sidewall (spacer) besides the base structures. Nano-gaps are fabricated between two adjacent spacers whereas the width of the gap depends on the gap between two adjacent base structures minus width of adjacent spacers. We demonstrate the process using a 32 nm node complementary metal oxide semiconductor (CMOS) platform to show its compatibility for very large scale heterogeneous integration of top-down and bottom-up fabrication as well as conventional and selfassembled nanodevices. This process opens up clear opportunity to overcome the decade long challenge of high density integration of self-assembled devices with precise position control. © 2012 IEEE.

  16. Sub-15 nm nano-pattern generation by spacer width control for high density precisely positioned self-assembled device nanomanufacturing

    KAUST Repository

    Rojas, Jhonathan Prieto

    2012-08-01

    We present a conventional micro-fabrication based thin film vertical sidewall (spacer) width controlled nano-gap fabrication process to create arrays of nanopatterns for high density precisely positioned self-assembled nanoelectronics device integration. We have used conventional optical lithography to create base structures and then silicon nitride (Si 3N4) based spacer formation via reactive ion etching. Control of Si3N4 thickness provides accurate control of vertical sidewall (spacer) besides the base structures. Nano-gaps are fabricated between two adjacent spacers whereas the width of the gap depends on the gap between two adjacent base structures minus width of adjacent spacers. We demonstrate the process using a 32 nm node complementary metal oxide semiconductor (CMOS) platform to show its compatibility for very large scale heterogeneous integration of top-down and bottom-up fabrication as well as conventional and selfassembled nanodevices. This process opens up clear opportunity to overcome the decade long challenge of high density integration of self-assembled devices with precise position control. © 2012 IEEE.

  17. ATLAS ITk Short Strip Prototype Module with Integrated DCDC Powering and Control Phase II Upgrade of the ATLAS Inner Tracker detector at the HL - LHC

    CERN Document Server

    Greenall, Ashley; The ATLAS collaboration

    2017-01-01

    The prototype Barrel module design, for the Phase II upgrade of the of the new Inner Tracker (ITk) detector at the LHC, has adopted an integrated low mass assembly featuring single-sided flexible circuits, with readout ASICs, glued to the silicon strip sensor. Further integration has been achieved by the attachment of module DCDC powering, HV sensor biasing switch and autonomous monitoring and control to the sensor. This low mass, integrated module approach benefits further in a reduced width stave structure to which the modules are attached. The results of preliminary electrical tests of such an integrated module will be presented.

  18. System control module diagnostic Expert Assistant

    Science.gov (United States)

    Flores, Luis M.; Hansen, Roger F.

    1990-01-01

    The Orbiter EXperiments (OEX) Program was established by NASA's Office of Aeronautics and Space Technology (OAST) to accomplish the precise data collection necessary to support a complete and accurate assessment of Space Transportation System (STS) Orbiter performance during all phases of a mission. During a mission, data generated by the various experiments are conveyed to the OEX System Control Module (SCM) which arranges for and monitors storage of the data on the OEX tape recorder. The SCM Diagnostic Expert Assistant (DEA) is an expert system which provides on demand advice to technicians performing repairs of a malfunctioning SCM. The DEA is a self-contained, data-driven knowledge-based system written in the 'C' Language Production System (CLIPS) for a portable micro-computer of the IBM PC/XT class. The DEA reasons about SCM hardware faults at multiple levels; the most detailed layer of encoded knowledge of the SCM is a representation of individual components and layouts of the custom-designed component boards.

  19. Effect of Dynamic Reheating Controlled by the Weaving Width on the Microstructure of GTA Bead-On-Pipe Weld Metal of 25% Cr Super Duplex Stainless Steel

    Directory of Open Access Journals (Sweden)

    Hee-Joon Sung

    2018-05-01

    Full Text Available Gas tungsten arc welding (GTAW with three different heat inputs controlled by the weaving width was performed to understand their effects on the microstructural changes during bead-on-pipe welding of super duplex stainless steel. The microstructure of the weld metals was categorized into three different types of zones: non-reheated, reheated type, and reheating-free zone. Even though single-pass welding with different weaving widths was employed, a reheated microstructure was detected, which has been previously observed with multiple pass welding. This phenomenon was called “dynamic reheating”, because it was produced by the weaving operation during welding regardless of the weaving width. The categorized area fraction varied with the weaving width change. Electron backscatter diffraction (EBSD results at the edge (the area near the fusion line of the low-heat-input condition indicated a higher austenite volume fraction and a lower Cr2N fraction than that of the medium heat input condition. Thus, it described an inverse relationship, because higher heat input provided a lower austenite fraction. In addition, it was observed clearly that the austenite fraction at the medium heat input condition was dramatically increased by reheating, while the Cr2N fraction was reduced. Regardless of the weaving width, reheating contributed to the increase of the austenite fraction, further reducing the Cr2N quantity. The edge areas in the map showed an inverse relationship in the reheated area fraction between low heat input and medium heat input. For this reason, the austenite fraction on the weld metal was determined not only by the heat input, but also by the amount of reheating.

  20. Auxiliary controller for time-to-digital converter module readout

    International Nuclear Information System (INIS)

    Ermolin, Yu.V.

    1992-01-01

    The KD-225 auxiliary controller for time-to-digital converter module readout in the SUMMA crate is described. After readout and preliminary processing the data are written in the P-140 buffer memory module. The controller is used in the FODS-2 experimental setup data acquisition system. 12 refs.; 1 fig

  1. Programming Programmable Logic Controller. High-Technology Training Module.

    Science.gov (United States)

    Lipsky, Kevin

    This training module on programming programmable logic controllers (PLC) is part of the memory structure and programming unit used in a packaging systems equipment control course. In the course, students assemble, install, maintain, and repair industrial machinery used in industry. The module contains description, objectives, content outline,…

  2. Controlling a Chaotic System through Control Parameter Self-Modulation

    International Nuclear Information System (INIS)

    Pastor, I.

    1994-01-01

    A method for obtaining active control of a chaotic system based on the modulation of a control parameter by adding to it a small perturbation proportional to one output signal is proposed. From a theoretical point of view, chaos can be stabilized in the framework of this method because small modifications of the vector field controlling the dynamics are allowed, and thus some of the previously existing unstable periodic trajectories can be made stable. The method is much inspired on recent treatments of some related problems, and it is compared with them. One of its most attractive features is that it should be very easy to implement it on real experiments. The method is tested on a system of ordinary differential equations modelling the coupling of two self-oscillating electronic circuits (van der Pol oscillators). Some brief comments are made on the possibility that it could be applied to complex spatio-temporal systems where multiple chaotic structures can coexist for some values of the control parameters

  3. Controlling a Chaotic System through Control Parameter Self-Modulation

    International Nuclear Information System (INIS)

    Pastor, I.

    1994-01-01

    A method for obtaining active control of a chaotic system based on the modulation of a control parameter by adding to it a small perturbation proportional to one output signal is proposed. From a theoretical point of view, chaos can be stabilized in the framework of this method because small modifications of the vector field controlling the dynamics are allowed, and thus some of the previously oxi sting unstable periodic trajectories can be made stable. The method is much inspired on recent treatments of some related problems, and i t is compared with them. One of its most attractive features is that is should be very easy to implement it on real experiments. The method is tested on a system of ordinary differential equations model ling the coupling of two se If - oscillating electronic circuits (van der Pol oscillators). Some brief comments are made on the no possibility that it could be applied to complex spatio-temporal systems where multiple chaotic structures can coexist for some values of the control parameters. (Author) 28 refs

  4. Controlling a Chaotic System through Control Parameter Self-Modulation

    Energy Technology Data Exchange (ETDEWEB)

    Pastor, I

    1994-07-01

    A method for obtaining active control of a chaotic system based on the modulation of a control parameter by adding to it a small perturbation proportional to one output signal is proposed. From a theoretical point of view, chaos can be stabilized in the framework of this method because small modifications of the vector field controlling the dynamics are allowed, and thus some of the previously oxi sting unstable periodic trajectories can be made stable. The method is much inspired on recent treatments of some related problems, and i t is compared with them. One of its most attractive features is that is should be very easy to implement it on real experiments. The method is tested on a system of ordinary differential equations model ling the coupling of two se If - oscillating electronic circuits (van der Pol oscillators). Some brief comments are made on the no possibility that it could be applied to complex spatio-temporal systems where multiple chaotic structures can coexist for some values of the control parameters. (Author) 28 refs.

  5. Controlling traffic jams by time modulating the safety distance

    DEFF Research Database (Denmark)

    Gaididei, Yu B.; Gorria, C.; Berkemer, R.

    2013-01-01

    The possibility of controlling traffic dynamics by applying high-frequency time modulation of traffic flow parameters is studied. It is shown that the region of the car density where the uniform (free) flow is unstable changes in the presence of time modulation compared with the unmodulated case....

  6. Embedded software for the CEBAF RF Control Module

    International Nuclear Information System (INIS)

    Lahti, G.; Ashkenazi, I.; West, C.; Morgan, B.

    1991-01-01

    The CEBAF accelerator control system employs a distributed computer strategy. As part of this strategy, the RF control sub-system uses 342 RF Control Modules, one for each of four warm section beam forming cavities (i.e., choppers, buncher, capture) and 338 superconducting accelerating cavities. Each control module has its own microprocessor, which provides local intelligence to automatically control over 100 parameters, while keeping the user interface simple. The microprocessor controls analog and digital I/O, including the phase and gradient section, high power amplifier (HPA), and interlocks. Presently, the embedded code is used to commission the 14 RF control modules in the injector. This paper describes the operational experience of this complex real-time control system

  7. Some auxiliary technology equipment for ATLAS hadron calorimeter module and submodule manipulations and the quality control of the assembled module

    International Nuclear Information System (INIS)

    Budagov, Yu.; Lebedev, A.; Lomakin, Yu.; Romanov, V.; Rusakovich, N.; Shchelchkov, A.; Sisakyan, A.; Sorokina, Yu.; Topilin, N.; Kul'chitskij, Yu.

    1997-01-01

    Describing of the auxiliary technology equipment for the submodule and module manipulations is presented. The results of the 0-module beam incoming control are given. The variations of the assembled module control measurements are described. The description of the construction for the 0-module transportation is presented

  8. Optical metrology for advanced process control: full module metrology solutions

    Science.gov (United States)

    Bozdog, Cornel; Turovets, Igor

    2016-03-01

    Optical metrology is the workhorse metrology in manufacturing and key enabler to patterning process control. Recent advances in device architecture are gradually shifting the need for process control from the lithography module to other patterning processes (etch, trim, clean, LER/LWR treatments, etc..). Complex multi-patterning integration solutions, where the final pattern is the result of multiple process steps require a step-by-step holistic process control and a uniformly accurate holistic metrology solution for pattern transfer for the entire module. For effective process control, more process "knobs" are needed, and a tighter integration of metrology with process architecture.

  9. Remotely powered and controlled EAPap actuator by amplitude modulated microwaves

    International Nuclear Information System (INIS)

    Yang, Sang Yeol; Mahadeva, Suresha K; Kim, Jaehwan

    2013-01-01

    This paper reports on a remotely powered and controlled Electro-Active Paper (EAPap) actuator without onboard controller using amplitude modulated microwaves. A rectenna is a key element for microwave power transmission that converts microwaves into dc power through coupling and rectification. In this study, the concept of a remotely controlled and powered EAPap actuator is proposed by means of modulating microwaves with a control signal and demodulating it through the rectenna rectification. This concept is applied to a robust EAPap actuator, namely cellulose–polypyrrole–ionic liquid (CPIL) EAPap. Details of fabrication and characterization of the rectenna and the CPIL-EAPap actuator are explained. Also, the charge accumulation problem of the actuator is explained and resolved by connecting an additional resistor. Since this idea can eliminate the onboard controller by supplying the operating signal through modulation, a compact and lightweight actuator can be achieved, which is useful for biomimetic robots and remotely driven actuators. (technical note)

  10. MCC: the Module Controller Chip for the ATLAS Pixel Detector

    International Nuclear Information System (INIS)

    Beccherle, R.; Darbo, G.; Gagliardi, G.; Gemme, C.; Morettini, P.; Musico, P.; Osculati, B.; Oppizzi, P.; Pratolongo, F.; Ruscino, E.; Schiavi, C.; Vernocchi, F.; Blanquart, L.; Einsweiler, K.; Meddeler, G.; Richardson, J.; Comes, G.; Fischer, P.; Calvet, D.; Boyd, R.; Sicho, P.

    2002-01-01

    In this article we describe the architecture of the Module Controller Chip for the ATLAS Pixel Detector. The project started in 1997 with the definition of the system specifications. A first fully-working rad-soft prototype was designed in 1998, while a radiation hard version was submitted in 2000. The 1998 version was used to build pixel detector modules. Results from those modules and from the simulated performance in ATLAS are reported. In the article we also describe the hardware/software tools developed to test the MCC performance at the LHC event rate

  11. Bilingual Contexts Modulate the Inhibitory Control Network

    Directory of Open Access Journals (Sweden)

    Jing Yang

    2018-03-01

    Full Text Available The present functional magnetic resonance imaging (fMRI study investigated influences of language contexts on inhibitory control and the underlying neural processes. Thirty Cantonese–Mandarin–English trilingual speakers, who were highly proficient in Cantonese (L1 and Mandarin (L2, and moderately proficient in English (L3, performed a picture-naming task in three dual-language contexts (L1-L2, L2-L3, and L1-L3. After each of the three naming tasks, participants performed a flanker task, measuring contextual effects on the inhibitory control system. Behavioral results showed a typical flanker effect in the L2-L3 and L1-L3 condition, but not in the L1-L2 condition, which indicates contextual facilitation on inhibitory control performance by the L1-L2 context. Whole brain analysis of the fMRI data acquired during the flanker tasks showed more neural activations in the right prefrontal cortex and subcortical areas in the L2-L3 and L1-L3 condition on one hand as compared to the L1-L2 condition on the other hand, suggesting greater involvement of the cognitive control areas when participants were performing the flanker task in L2-L3 and L1-L3 contexts. Effective connectivity analyses displayed a cortical-subcortical-cerebellar circuitry for inhibitory control in the trilinguals. However, contrary to the right-lateralized network in the L1-L2 condition, functional networks for inhibitory control in the L2-L3 and L1-L3 condition are less integrated and more left-lateralized. These findings provide a novel perspective for investigating the interaction between bilingualism (multilingualism and inhibitory control by demonstrating instant behavioral effects and neural plasticity as a function of changes in global language contexts.

  12. Grid-connected of photovoltaic module using nonlinear control

    DEFF Research Database (Denmark)

    El Fadil, H.; Giri, F.; Guerrero, Josep M.

    2012-01-01

    The problem of controlling single-phase grid connected photovoltaic (PV) system is considered. The control objective is fourfold: (i) asymptotic stability of the closed loop system, (ii) maximum power point tracking (MPPT) of PV module (iii) tight regulation of the DC bus voltage, and (iv) unity...

  13. Pressure tracking control of vehicle ABS using piezo valve modulator

    Science.gov (United States)

    Jeon, Juncheol; Choi, Seung-Bok

    2011-03-01

    This paper presents a wheel slip control for the ABS(anti-lock brake system) of a passenger vehicle using a controllable piezo valve modulator. The ABS is designed to optimize for braking effectiveness and good steerability. As a first step, the principal design parameters of the piezo valve and pressure modulator are appropriately determined by considering the braking pressure variation during the ABS operation. The proposed piezo valve consists of a flapper, pneumatic circuit and a piezostack actuator. In order to get wide control range of the pressure, the pressure modulator is desired. The modulator consists of a dual-type cylinder filled with different substances (fluid and gas) and a piston rod moving vertical axis to transmit the force. Subsequently, a quarter car wheel slip model is formulated and integrated with the governing equation of the piezo valve modulator. A sliding mode controller to achieve the desired slip rate is then designed and implemented. Braking control performances such as brake pressure and slip rate are evaluated via computer simulations.

  14. Amplitude modulation control of escape from a potential well

    International Nuclear Information System (INIS)

    Chacón, R.; Martínez García-Hoz, A.; Miralles, J.J.; Martínez, P.J.

    2014-01-01

    We demonstrate the effectiveness of periodic amplitude modulations in controlling (suppressing and enhancing) escape from a potential well through the universal model of a damped Helmholtz oscillator subjected to an external periodic excitation (the escape-inducing excitation) whose amplitude is periodically modulated (the escape-controlling excitation). Analytical and numerical results show that this multiplicative control works reliably for different subharmonic resonances between the two periodic excitations involved, and that its effectiveness is comparable to those of different methods of additive control. Additionally, we demonstrate the robustness of the multiplicative control against the presence of low-intensity Gaussian noise. -- Highlights: •Multiplicative control of escape from a potential well has been demonstrated. •Theoretical predictions are obtained from a Melnikov analysis. •It has been shown the robustness of the multiplicative control against noise.

  15. Caffeine Does Not Modulate Inhibitory Control

    Science.gov (United States)

    Tieges, Zoe; Snel, Jan; Kok, Albert; Ridderinkhof, K. Richard

    2009-01-01

    The effects of a 3 mg/kg body weight (BW) dose of caffeine were assessed on behavioral indices of response inhibition. To meet these aims, we selected a modified AX version of the Continuous Performance Test (CPT), the stop task, and the flanker task. In three double-blind, placebo-controlled, within-subjects experiments, these tasks were…

  16. Modulation linearization of a frequency-modulated voltage controlled oscillator, part 3

    Science.gov (United States)

    Honnell, M. A.

    1975-01-01

    An analysis is presented for the voltage versus frequency characteristics of a varactor modulated VHF voltage controlled oscillator in which the frequency deviation is linearized by using the nonlinear characteristics of a field effect transistor as a signal amplifier. The equations developed are used to calculate the oscillator output frequency in terms of pertinent circuit parameters. It is shown that the nonlinearity exponent of the FET has a pronounced influence on frequency deviation linearity, whereas the junction exponent of the varactor controls total frequency deviation for a given input signal. A design example for a 250 MHz frequency modulated oscillator is presented.

  17. Direct Load Control by AC Frequency Modulation

    DEFF Research Database (Denmark)

    Douglass, Philip James; You, Shi

    2012-01-01

    Fine-grained under frequency load shedding called “demand as a frequency controlled reserve“ (DFCR) has been shown to be a promising method of providingfrequency regulation service from distributed loads [1]. Micro-grids with a large portion of intermittent renewable generation will benefit greatly...... from this technology because their low inertia. The paper proposes a operating procedure for utilizing DFCR loads for energy balancing, expanding DFCR’s well known role as a power balancing resource. The system operator can use DFCR for energy balancing by adjusting the frequency controller...... of generators to schedule off-nominal system frequency values. The feasibility of the proposed system is evaluated on an existing small island power system....

  18. Level width broadening effect

    International Nuclear Information System (INIS)

    Zhang Jingshang

    2003-01-01

    In file-6 for double-differential cross sections, the level width broadening effect should be taken into account properly due to Heisenberg' uncertainty. Besides level width broadening effect, the energy resolution in the measurements is also needed in fitting measurement procedure. In general, the traditional normal Gaussian expansion is employed. However, to do so in this way the energy balance could not be held. For this reason, the deformed Gaussian expansion functions with exponential form for both the single energy point and continuous spectrum are introduced, with which the normalization and energy balance conditions could be held exactly in the analytical form. (author)

  19. Comparison of radiographic joint space width and magnetic resonance imaging for prediction of knee replacement: A longitudinal case-control study from the Osteoarthritis Initiative

    International Nuclear Information System (INIS)

    Eckstein, Felix; Wirth, Wolfgang; Cotofana, Sebastian; Boudreau, Robert; Wang, Zhijie; Hannon, Michael J.; Duryea, Jeff; Guermazi, Ali; Roemer, Frank; Nevitt, Michael; John, Markus R.; Ladel, Christoph; Sharma, Leena; Hunter, David J.; Kwoh, C.K.

    2016-01-01

    To evaluate whether change in fixed-location measures of radiographic joint space width (JSW) and cartilage thickness by MRI predict knee replacement. Knees replaced between 36 and 60 months' follow-up in the Osteoarthritis Initiative were each matched with one control by age, sex and radiographic status. Radiographic JSW was determined from fixed flexion radiographs and subregional femorotibial cartilage thickness from 3 T MRI. Changes between the annual visit before replacement (T 0 ) and 2 years before T 0 (T -2 ) were compared using conditional logistic regression. One hundred and nineteen knees from 102 participants (55.5 % women; age 64.2 ± 8.7 [mean ± SD] years) were studied. Fixed-location JSW change at 22.5 % from medial to lateral differed more between replaced and control knees (case-control [cc] OR = 1.57; 95 % CI: 1.23-2.01) than minimum medial JSW change (ccOR = 1.38; 95 % CI: 1.11-1.71). Medial femorotibial cartilage loss displayed discrimination similar to minimum JSW, and central tibial cartilage loss similar to fixed-location JSW. Location-independent thinning and thickening scores were elevated prior to knee replacement. Discrimination of structural progression between knee pre-placement cases versus controls was stronger for fixed-location than minimum radiographic JSW. MRI displayed similar discrimination to radiography and suggested greater simultaneous cartilage thickening and loss prior to knee replacement. (orig.)

  20. Comparison of radiographic joint space width and magnetic resonance imaging for prediction of knee replacement: A longitudinal case-control study from the Osteoarthritis Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Eckstein, Felix; Wirth, Wolfgang; Cotofana, Sebastian [Paracelsus Medical University Salzburg and Nuremberg Austria and Chondrometrics GmbH, Institute of Anatomy, Ainring (Germany); Boudreau, Robert [University of Pittsburgh, Department of Epidemiology, Graduate School of Public Health, Pittsburgh, PA (United States); Wang, Zhijie; Hannon, Michael J. [University of Pittsburgh and Pittsburgh VAHS, Division of Rheumatology and Clinical Immunology, Pittsburgh, PA (United States); Duryea, Jeff [Brigham and Women' s Hospital, Harvard Medical School, Boston, MA (United States); Guermazi, Ali [Boston University School of Medicine and Boston Imaging Core Lab (BICL), LLC, Boston, MA (United States); Roemer, Frank [Boston University School of Medicine and Boston Imaging Core Lab (BICL), LLC, Boston, MA (United States); University of Erlangen-Nuremberg, Department of Radiology, Erlangen (Germany); Nevitt, Michael [OAI Coordinating Ctr., UCSF, San Francisco, CA (United States); John, Markus R. [Novartis Pharma AG, Basel (Switzerland); Ladel, Christoph [Merck KGaA, Darmstadt (Germany); Sharma, Leena [Northwestern University, Department of Medicine, Feinberg School of Medicine, Chicago, IL (United States); Hunter, David J. [University Sydney, Royal North Shore Hospital and Institute of Bone and Joint Research, Kolling Institute, Sydney, NSW (Australia); Kwoh, C.K. [University of Arizona, Division of Rheumatology and the University of Arizona Arthritis Center, Tucson, AZ (United States); Collaboration: OAI Investigators

    2016-06-15

    To evaluate whether change in fixed-location measures of radiographic joint space width (JSW) and cartilage thickness by MRI predict knee replacement. Knees replaced between 36 and 60 months' follow-up in the Osteoarthritis Initiative were each matched with one control by age, sex and radiographic status. Radiographic JSW was determined from fixed flexion radiographs and subregional femorotibial cartilage thickness from 3 T MRI. Changes between the annual visit before replacement (T{sub 0}) and 2 years before T{sub 0} (T{sub -2}) were compared using conditional logistic regression. One hundred and nineteen knees from 102 participants (55.5 % women; age 64.2 ± 8.7 [mean ± SD] years) were studied. Fixed-location JSW change at 22.5 % from medial to lateral differed more between replaced and control knees (case-control [cc] OR = 1.57; 95 % CI: 1.23-2.01) than minimum medial JSW change (ccOR = 1.38; 95 % CI: 1.11-1.71). Medial femorotibial cartilage loss displayed discrimination similar to minimum JSW, and central tibial cartilage loss similar to fixed-location JSW. Location-independent thinning and thickening scores were elevated prior to knee replacement. Discrimination of structural progression between knee pre-placement cases versus controls was stronger for fixed-location than minimum radiographic JSW. MRI displayed similar discrimination to radiography and suggested greater simultaneous cartilage thickening and loss prior to knee replacement. (orig.)

  1. Comparison of Radiographic Joint Space Width and Magnetic-Resonance-Imaging for Prediction of Knee Replacement – A Longitudinal Case-Control Study from the Osteoarthritis Initiative

    Science.gov (United States)

    Eckstein, Felix; Boudreau, Robert; Wang, Zhijie; Hannon, Michael J.; Duryea, Jeff; Wirth, Wolfgang; Cotofana, Sebastian; Guermazi, Ali; Roemer, Frank; Nevitt, Michael; John, Markus R.; Ladel, Christoph; Sharma, Leena; Hunter, David J.; Kwoh, C. Kent

    2015-01-01

    Objective To evaluate whether change in fixed location measures of radiographic joint space width (JSW) and in cartilage thickness by MRI predict knee replacement. Methods Knees replaced between 36-60 months follow-up (M) in the Osteoarthritis Initiative were each matched with one control by age, sex, and radiographic status. Radiographic JSW was determined from fixed flexion radiographs, and subregional femorotibial cartilage thickness from 3 Tesla MRI. Changes between the annual visit before replacement (T0) and 2 years before T0 (T-2) were compared using conditional logistic regression. Results One hundred and nineteen knees from 102 participants (55.5% women; age 64.2±8.7 [mean±SD]) were studied. Fixed location JSW change at 22.5% from medial to lateral differed more between replaced and control knees (case-control [cc] OR=1.57; 95%CI: 1.23,2.01) than minimum medial JSW change (ccOR=1.38; 95%CI: 1.11,1.71). Medial femorotibial cartilage loss displayed discrimination similar to minimum JSW, and central tibial cartilage loss similar to fixed location JSW. Location-independent thinning and thickening scores were both elevated prior to knee replacement. Conclusions Discrimination of structural progression between knee pre-placement cases versus controls was stronger for fixed-location than for minimum radiographic JSW. MRI displayed similar discrimination to radiography and suggested greater simultaneous cartilage thickening and loss prior to knee replacement. PMID:26376884

  2. Logic and control module for the Fermilab booster beam damper

    International Nuclear Information System (INIS)

    Sandberg, B.R.

    1977-01-01

    A logic and control module is included in the electronic system of the booster superdamper. This module produces a 9-bit digital word that controls the delay of beam bunch position information in the Fermilab booster synchrotron so that it arrives at the damping electrodes at the same time as the bunch of beam to be corrected. This delay word generator also has an output feature that only allows delay time decreases as the booster synchrotron frequency program increases monotonically. Such a feature guards against low-index incidental FM from affecting the delay computations

  3. Quasi-periodic dynamics in system with multilevel pulse modulated control

    Science.gov (United States)

    Gol'tsov, Yu A.; Kizhuk, A. S.; Rubanov, V. G.

    2018-03-01

    In this paper, the authors describe the transitions from the regular periodic mode to quasiperiodicity that can be observed in a multilevel pulse-width modulated control system for a high-power heating unit. The behavior of such system can be described by a set of two coupled non-autonomous differential equations with discontinuous right-hand sides. The authors reduce the investigation of this system to the studying of a two-dimensional piecewise-smooth map. The authors demonstrate how a closed invariant curve associated with quasiperiodic dynamics can arise from a stable periodic motion through a border-collision bifurcation. The paper also considers a variety of interesting nonlinear phenomena, including phase-locking modes, the coexistence of several stable closed invariant curves, embedded one into the other and with their basins of attraction separated by intervening repelling closed curves.

  4. Singing modulates parvalbumin interneurons throughout songbird forebrain vocal control circuitry

    Science.gov (United States)

    Zengin-Toktas, Yildiz

    2017-01-01

    Across species, the performance of vocal signals can be modulated by the social environment. Zebra finches, for example, adjust their song performance when singing to females (‘female-directed’ or FD song) compared to when singing in isolation (‘undirected’ or UD song). These changes are salient, as females prefer the FD song over the UD song. Despite the importance of these performance changes, the neural mechanisms underlying this social modulation remain poorly understood. Previous work in finches has established that expression of the immediate early gene EGR1 is increased during singing and modulated by social context within the vocal control circuitry. Here, we examined whether particular neural subpopulations within those vocal control regions exhibit similar modulations of EGR1 expression. We compared EGR1 expression in neurons expressing parvalbumin (PV), a calcium buffer that modulates network plasticity and homeostasis, among males that performed FD song, males that produced UD song, or males that did not sing. We found that, overall, singing but not social context significantly affected EGR1 expression in PV neurons throughout the vocal control nuclei. We observed differences in EGR1 expression between two classes of PV interneurons in the basal ganglia nucleus Area X. Additionally, we found that singing altered the amount of PV expression in neurons in HVC and Area X and that distinct PV interneuron types in Area X exhibited different patterns of modulation by singing. These data indicate that throughout the vocal control circuitry the singing-related regulation of EGR1 expression in PV neurons may be less influenced by social context than in other neuron types and raise the possibility of cell-type specific differences in plasticity and calcium buffering. PMID:28235074

  5. Spectral modulation through controlling anions in nanocaged phosphors

    NARCIS (Netherlands)

    Bian, H.; Liu, Y.; Yan, D.; Zhu, H.; Liu, C.; Xu, C.S.; Liu, Y.; Zhang, H.; Wang, X.

    2013-01-01

    A new approach has been proposed and validated to modulate the emission spectra of europium-doped 12CaO center dot 7Al(2)O(3) phosphors by tuning the nonradiative and radiative transition rates, realized by controlling the sort and amount of the encaged anions. A single wavelength at 255 nm can

  6. Stokes line width

    International Nuclear Information System (INIS)

    Nikiskov, A.I.; Ritus, V.I.

    1993-01-01

    The concept of Stokes line width is introduced for the asymptotic expansions of functions near an essential singularity. Explicit expressions are found for functions (switching functions) that switch on the exponentially small terms for the Dawson integral, Airy function, and the gamma function. A different, more natural representation of a function, not associated with expansion in an asymptotic series, in the form of dominant and recessive terms is obtained by a special division of the contour integral which represents the function into contributions of higher and lower saddle points. This division leads to a narrower, natural Stokes line width and a switching function of an argument that depends on the topology of the lines of steepest descent from the saddle point

  7. Assessment of an Average Controller for a DC/DC Converter via Either a PWM or a Sigma-Delta-Modulator

    Directory of Open Access Journals (Sweden)

    R. Silva-Ortigoza

    2014-01-01

    Full Text Available Sliding mode control is a discontinuous control technique that is, by its nature, appropriate for controlling variable structure systems, such as the switch regulated systems employed in power electronics. However, when designing control laws based on the average models of these systems a modulator is necessary for their experimental implementation. Among the most widely used modulators in power electronics are the pulse width modulation (PWM and, more recently, the sigma-delta-modulator (Σ-Δ-modulator. Based on the importance of achieving an appropriate implementation of average control laws and the relevance of the trajectory tracking task in DC/DC power converters, for the first time, this research presents the assessment of the experimental results obtained when one of these controllers is implemented through either a PWM or a Σ-Δ-modulator to perform such a task. A comparative assessment based on the integral square error (ISE index shows that, at frequencies with similar efficiency, the Σ-Δ-modulator provides a better tracking performance for the DC/DC Buck converter. In this paper, an average control based on differential flatness was used to perform the experiments. It is worth mentioning that a different trajectory tracking controller could have been selected for this research.

  8. Capillary condensation and evaporation in alumina nanopores with controlled modulations.

    Science.gov (United States)

    Bruschi, Lorenzo; Mistura, Giampaolo; Liu, Lifeng; Lee, Woo; Gösele, Ulrich; Coasne, Benoit

    2010-07-20

    Capillary condensation in nanoporous anodic aluminum oxide presenting not interconnected pores with controlled modulations is studied using adsorption experiments and molecular simulations. Both the experimental and simulation data show that capillary condensation and evaporation are driven by the smallest size of the nanopore (constriction). The adsorption isotherms for the open and closed pores are almost identical if constrictions are added to the system. The latter result implies that the type of pore ending does not matter in modulated pores. Thus, the presence of hysteresis loops observed in adsorption isotherms measured in straight nanopores with closed bottom ends can be explained in terms of geometrical inhomogeneities along the pore axis. More generally, these results provide a general picture of capillary condensation and evaporation in constricted or modulated pores that can be used for the interpretation of adsorption in disordered porous materials.

  9. Matlab Stability and Control Toolbox: Trim and Static Stability Module

    Science.gov (United States)

    Crespo, Luis G.; Kenny, Sean P.

    2006-01-01

    This paper presents the technical background of the Trim and Static module of the Matlab Stability and Control Toolbox. This module performs a low-fidelity stability and control assessment of an aircraft model for a set of flight critical conditions. This is attained by determining if the control authority available for trim is sufficient and if the static stability characteristics are adequate. These conditions can be selected from a prescribed set or can be specified to meet particular requirements. The prescribed set of conditions includes horizontal flight, take-off rotation, landing flare, steady roll, steady turn and pull-up/ push-over flight, for which several operating conditions can be specified. A mathematical model was developed allowing for six-dimensional trim, adjustable inertial properties, asymmetric vehicle layouts, arbitrary number of engines, multi-axial thrust vectoring, engine(s)-out conditions, crosswind and gyroscopic effects.

  10. Performance and quality control of Clear-PEM detector modules

    International Nuclear Information System (INIS)

    Amaral, Pedro; Carrico, Bruno; Ferreira, Miguel; Moura, Rui; Ortigao, Catarina; Rodrigues, Pedro; Da Silva, Jose C.; Trindade, Andreia; Varela, Joao

    2007-01-01

    Clear-PEM is a dedicated PET scanner for breast and axilla cancer diagnosis, under development within the framework of the Crystal Clear Collaboration at CERN, aiming at the detection of tumors down to 2 mm in diameter. The camera consists of two planar detector heads with active dimensions 16.0x14.5 cm 2 . Each head has 96 Clear-PEM detector modules consisting of 32 LYSO:Ce pixels with dimensions 2x2x20 mm 3 packed in a 4x8 BaSO 4 reflector matrix compressed between two Hamamatsu S8550 APD arrays in a double-readout configuration for Depth-of-Interaction (DoI) determination. The modules are individually measured and characterized before being grouped into Supermodules (comprised of 24 modules). Measured properties include photo-peak position, relative gain dispersion, energy resolution, cross-talk and DoI resolution. Optical inspection of matrices was also performed with the aid of a microscope, to search for pixel misalignments and matrix defects. Modules' performance was thoroughly evaluated with a 511 keV collimated beam to exactly determine DoI resolution. In addition, a fast quality control (QC) procedure using flood irradiations from a 137 Cs source was applied systematically. The overall performance of the 24 detector modules complies with the design goals of the Clear-PEM detector, showing energy resolution around 15%, DoI resolution of about 2 mm and gain dispersion among pixels of 15%

  11. The effect of feedback-controlled divertor nitrogen seeding on the boundary plasma and power exhaust channel width in Alcator C-Mod

    Science.gov (United States)

    Labombard, B.; Brunner, D.; Kuang, A. Q.; McCarthy, W.; Terry, J. L.

    2017-10-01

    The scrape-off layer (SOL) power channel width, λq, is projected to be 0.5 mm in power reactors, based on multi-machine measurements of divertor target heat fluxes in H-mode at low levels of divertor dissipation. An important question is: does λq change with the level of divertor dissipation? We report results in which feedback controlled nitrogen seeding in the divertor was used to systematically vary divertor dissipation in a series of otherwise identical L-mode plasmas at three plasma currents: 0.55, 0.8 and 1.1 MA. Outer midplane profiles were recorded with a scanning Mirror Langmuir Probe; divertor plasma conditions were monitored with `rail' Langmuir probe and surface thermocouple arrays. Despite an order of magnitude reduction in divertor target heat fluxes (q// 400 MW m-2 to 40 MW m-2) and corresponding change in divertor regime from sheath-limited through high-recycling to near-detached, the upstream electron temperature profile is found to remain unchanged or to become slightly steeper in the near SOL and to drop significantly in the far SOL. Thus heat in the SOL appears to take advantage of this impurity radiation `heat sink' in the divertor by preferentially draining via the narrow (and perhaps an increasingly narrow) λq of the near SOL. Supported by USDoE award DE-FC02-99ER54512.

  12. Pulse-width discriminators

    International Nuclear Information System (INIS)

    Budyashov, Yu.G.; Grebenyuk, V.M.; Zinov, V.G.

    1978-01-01

    A pulse duration discriminator is described which is intended for processing signals from multilayer scintillators. The basic elements of the scintillator are: an input gate, a current generator, an integrating capacitor, a Schmidt trigger and an anticoincidence circuit. The basic circuit of the discriminator and its time diagrams explaining its operating are given. The discriminator is based on microcircuits. Pulse duration discrimination threshold changes continuously from 20 to 100 ns, while its amplitude threshold changes within 20 to 100 mV. The temperature instability of discrimination thresholds (both in pulse width and in amplitude) is better than 0.1 per cent/deg C

  13. Application of CPLD in CSR power supply control module

    International Nuclear Information System (INIS)

    Liu Caihong; Guo Yuhui; Chinese Academy of Sciences, Beijing; Jing Lan; Qiao Weimin

    2005-01-01

    A realization of Single Chip Microcomputer peripheral interface in HIRFL-CSR power supply control module based on CPLD is presented in the paper. It integrates flip-latch, coding unit, data bus, frequency division unit, logical compare unit, counter and logic circuit into a single CPLD chip, and dramatically decreases the area of PCB and increase system reliability, at the same time the whole system's flexibility has been evidently improved because of the CPLD's in-system programmable characteristics. (authors)

  14. Quality control of specific patient in radiotherapy with modulated intensity

    International Nuclear Information System (INIS)

    Aberbuj, P D; Tapia Coca, R C

    2012-01-01

    In this work we comment the details of the patient specific quality controls of the first Intensity Modulated Radiotherapy treatment done at Roffo Institute. These controls consisted in two sets of measurements: absolute dose with ionization chamber and relative dose with two dosimetric systems (Gafchromic EBT2 radiochromic films and the PTW 729 ionization chambers array). Two of the filters did not pass the dosimetrical tests, and they were manufactured again. The new filters passed the tests. For the relative two-dimensional measurements the radiochromic films had a better performance than the array due to their higher spatial resolution (author)

  15. Influence of MLC leaf width on biologically adapted IMRT plans

    Energy Technology Data Exchange (ETDEWEB)

    Roedal, Jan; Soevik, Aaste; Malinen, Eirik (Dept. of Medical Physics, The Norwegian Radium Hospital, Oslo Univ. Hospital, Oslo (Norway)), E-mail: jan.rodal@radiumhospitalet.no

    2010-10-15

    Introduction. High resolution beam delivery may be required for optimal biology-guided adaptive therapy. In this work, we have studied the influence of multi leaf collimator (MLC) leaf widths on the treatment outcome following adapted IMRT of a hypoxic tumour. Material and methods. Dynamic contrast enhanced MR images of a dog with a spontaneous tumour in the nasal region were used to create a tentative hypoxia map following a previously published procedure. The hypoxia map was used as a basis for generating compartmental gross tumour volumes, which were utilised as planning structures in biologically adapted IMRT. Three different MLCs were employed in inverse treatment planning, with leaf widths of 2.5 mm, 5 mm and 10 mm. The number of treatment beams and the degree of step-and-shoot beam modulation were varied. By optimising the tumour control probability (TCP) function, optimal compartmental doses were derived and used as target doses in the inverse planning. Resulting IMRT dose distributions and dose volume histograms (DVHs) were exported and analysed, giving estimates of TCP and compartmental equivalent uniform doses (EUDs). The impact of patient setup accuracy was simulated. Results. The MLC with the smallest leaf width (2.5 mm) consistently gave the highest TCPs and compartmental EUDs, assuming no setup error. The difference between this MLC and the 5 mm MLC was rather small, while the MLC with 10 mm leaf width gave considerably lower TCPs. When including random and systematic setup errors, errors larger than 5 mm gave only small differences between the MLC types. For setup errors larger than 7 mm no differences were found between non-uniform and uniform dose distributions. Conclusions. Biologically adapted radiotherapy may require MLCs with leaf widths smaller than 10 mm. However, for a high probability of cure it is crucial that accurate patient setup is ensured.

  16. Production quality controls and geometric characterization of the IFMIF-RFQ modules via the usage of a Coordinate Measuring Machine

    Energy Technology Data Exchange (ETDEWEB)

    Ferrari, Luigi, E-mail: luigi.ferrari@lnl.infn.it [INFN-LNL Laboratori Nazionali di Legnaro, Legnaro (Italy); Palmieri, Antonio [INFN-LNL Laboratori Nazionali di Legnaro, Legnaro (Italy); Pepato, Adriano; Prevedello, Alessandro; Dima, Razvan; Udup, Emil [INFN-Sezione di Padova, Padova (Italy)

    2017-02-15

    Highlights: • The production phases of the IFMIF-RFQ Modules is introduced. • Metrological controls through production are described and some results reported. • Radio-Frequency test is introduced by using geometric considerations. • Results from metrology and RF test are compared. • Acceptance of the modules has been guaranteed from that comparison. - Abstract: The RFQ of the IFMIF/EVEDA project (Pérez et al., 2015) is a 9.8 m long cavity able to accelerate a 125 mA deuteron beam from the input energy of 50 keV/u to the output energy of 2.5 MeV/u. Such RFQ operates at the frequency of 175 MHz and is composed of 18 mechanical modules approximately 0.55 long each (Pepato et al., 2010) . The RFQ realization involves the I.N.F.N. Sections of Padova, Torino and Bologna, as well as the Legnaro National Laboratories (L.N.L.). The metrological measurements via CMM (Coordinate Measuring Machine) provided to be a very effective tool both for quality controls along the RFQ production phases and in the reconstruction of the cavity geometric profile for each RFQ module. The scans in the most sensitive regions with respect to RF frequency, such as modulation, tips, base-vane width and vessel height provided the values of the cavity deviations from nominal geometry to be compared with design physic-driven tolerances and with RF measurements. Moreover, the comparison between mechanical and RF measurements suggests a methodology for the geometric reconstruction of the cavity axis and determines the final machining of the end surfaces of each module in view of the coupling with the adjacent ones. In this paper a detailed description of the metrological procedures and tests and of the RFQ along its production and assembly phases will be given and it will be shown that the adopted procedure allowed the attainment of the tuning range specifications for each RFQ module.

  17. Width of electromagnetic wave instability spectrum in tungsten plate

    International Nuclear Information System (INIS)

    Rinkevich, A.B.

    1995-01-01

    Based on the study of high-frequency signal modulation and spectrum analysis of the envelope a measurement of spectrum width for electromagnetic wave instability was carried out under conditions of current pulse action on tungsten plate in magnetic field. The existence of amplitude-frequency wave modulation was revealed. The width of current disturbance spectrum in a specimen was evaluated. Current disturbances are shown to cause the instability of electromagnetic wave. 11 refs.; 6 figs

  18. 76 FR 78 - Federal Motor Vehicle Safety Standard; Engine Control Module Speed Limiter Device

    Science.gov (United States)

    2011-01-03

    ... [Docket No. NHTSA-2007-26851] Federal Motor Vehicle Safety Standard; Engine Control Module Speed Limiter... occupants. IIHS stated that on-board electronic engine control modules (ECM) will maintain the desired speed... be equipped with an electronic control module (ECM) that is capable of limiting the maximum speed of...

  19. Thermal equilibrium control by frequent bang-bang modulation.

    Science.gov (United States)

    Yang, Cheng-Xi; Wang, Xiang-Bin

    2010-05-01

    In this paper, we investigate the non-Markovian heat transfer between a weakly damped harmonic oscillator (system) and a thermal bath. When the system is initially in a thermal state and not correlated with the environment, the mean energy of the system always first increases, then oscillates, and finally reaches equilibrium with the bath, no matter what the initial temperature of the system is. Moreover, the heat transfer between the system and the bath can be controlled by fast bang-bang modulation. This modulation does work on the system, and temporarily inverts the direction of heat flow. In this case, the common sense that heat always transfers from hot to cold does not hold any more. At the long time scale, a new dynamic equilibrium is established between the system and the bath. At this equilibrium, the energy of the system can be either higher or lower than its normal equilibrium value. A comprehensive analysis of the relationship between the dynamic equilibrium and the parameters of the modulation as well as the environment is presented.

  20. PULSE MODULATION POWER AMPLIFIER WITH ENHANCED CASCADE CONTROL METHOD

    DEFF Research Database (Denmark)

    1998-01-01

    a single local feedback path A (7) with a lowpass characteristic and local forward blocks B¿1? or B (3, 4). The leads to a much improved system with a very low sensitivity to errors in the switching power stage. In the second preferred embodiment of the invention the control structure is extended...... and feedback path A to determine stable self-oscillating conditions. An implemented 250W example MECC digital power amplifier has proven superior performance in terms of audio performance (0.005 % distortion, 115 dB dynamic range) and efficiency (92 %).......A digital switching power amplifier with Multivariable Enhanced Cascade Controlled (MECC) includes a modulator, a switching power stage and a low pass filter. In the first preferred embodiment an enhanced cascade control structure local to the switching power stage is added, characterised by having...

  1. Frequency response control of semiconductor laser by using hybrid modulation scheme.

    Science.gov (United States)

    Mieda, Shigeru; Yokota, Nobuhide; Isshiki, Ryuto; Kobayashi, Wataru; Yasaka, Hiroshi

    2016-10-31

    A hybrid modulation scheme that simultaneously applies the direct current modulation and intra-cavity loss modulation to a semiconductor laser is proposed. Both numerical calculations using rate equations and experiments using a fabricated laser show that the hybrid modulation scheme can control the frequency response of the laser by changing a modulation ratio and time delay between the two modulations. The modulation ratio and time delay provide the degree of signal mixing of the two modulations and an optimum condition is found when a non-flat frequency response for the intra-cavity loss modulation is compensated by that for the direct current modulation. We experimentally confirm a 8.64-dB improvement of the modulation sensitivity at 20 GHz compared with the pure direct current modulation with a 0.7-dB relaxation oscillation peak.

  2. Divisive gain modulation of motoneurons by inhibition optimizes muscular control

    DEFF Research Database (Denmark)

    Vestergaard, Mikkel; Berg, Rune W.

    2015-01-01

    unclear whether the motoneuron gain, i.e., the slope of the transformation between synaptic input and spiking output, is also modulated to reduce variability in force. To address this issue, we use turtle hindlimb scratching as a model for fine motor control, since this behavior involves precise limb...... movement to rub the location of somatic nuisance touch. We recorded intracellularly from motoneurons in a reduced preparation where the limbs were removed to increase mechanical stability and the motor nerve activity served as a surrogate for muscle force. We found that not only is the gain of motoneurons...

  3. Controller Design for Direct Torque Controlled Space Vector Modulated (DTC-SVM) Induction Motor Drives

    DEFF Research Database (Denmark)

    Zelechowski, M.; Kazmierkowski, M.P.; Blaabjerg, Frede

    2005-01-01

    In this paper two different methods of PI controllers for direct torque controlled-space vector modulated induction motor drives have been studied. The first one is simple method based only on symmetric optimum criterion. The second approach takes into account the full model of induction motor in...

  4. Phase Modulation Method for Control Systems of Rotary Machine Parameters

    Directory of Open Access Journals (Sweden)

    V. V. Sychev

    2014-01-01

    Full Text Available Traditionally, vibration-based diagnostics takes the main place in a large complex of technical control means of rotary machine operation. It allows us to control the onset of extreme limit states of operating construction and its elements. However, vibration-based diagnostics is incapable to provide differentiated information about the condition of particular units, type of fault and point of its occurrence.From the practical experience of optoelectronic sensors development, methods of phase coding information about the behavior of the investigated object are known. They allow us to overcome the abovementioned disadvantage of vibration-based diagnostics through the modulation of the reflected radiation from the object. This phase modulation is performed with the image analyzers, in which the modulating raster (alternating transparent and nontransparent sectors is designed so, that the carrier frequency of oscillations is absent (suppressed in frequency spectrum, and all useful information can be found in the side frequencies.Carrier frequency suppression appears for two complete turns of the modulating raster. Each time during this process oscillations have a 180° phase shift (hop relatively to the initial oscillation on the boundary of each turn. It leads to a substantial increase in signal/noise ratio and possibility to conduct high-accuracy diagnostics.The principle of the pseudo inversion is used for measurements to suppress an adverse effect of various factors in dynamic control system. For this principle the leaving and returned beams practically go on the same way with small spatial shift. This shift occurs then the leaving beam reflects from a basic surface and the reflected – from the measured surface of the object. Therefore the measurements become insensitive to any other errors of system, except relative position of system «model-object».The main advantages of such measurements are the following:- system steadiness to error

  5. Modulation and control of matrix converter for aerospace application

    Science.gov (United States)

    Kobravi, Keyhan

    In the context of modern aircraft systems, a major challenge is power conversion to supply the aircraft's electrical instruments. These instruments are energized through a fixed-frequency internal power grid. In an aircraft, the available sources of energy are a set of variable-speed generators which provide variable-frequency ac voltages. Therefore, to energize the internal power grid of an aircraft, the variable-frequency ac voltages should be converted to a fixed-frequency ac voltage. As a result, an ac to ac power conversion is required within an aircraft's power system. This thesis develops a Matrix Converter to energize the aircraft's internal power grid. The Matrix Converter provides a direct ac to ac power conversion. A major challenge of designing Matrix Converters for aerospace applications is to minimize the volume and weight of the converter. These parameters are minimized by increasing the switching frequency of the converter. To design a Matrix Converter operating at a high switching frequency, this thesis (i) develops a scheme to integrate fast semiconductor switches within the current available Matrix Converter topologies, i.e., MOSFET-based Matrix Converter, and (ii) develops a new modulation strategy for the Matrix Converter. This Matrix Converter and the new modulation strategy enables the operation of the converter at a switching-frequency of 40kHz. To provide a reliable source of energy, this thesis also develops a new methodology for robust control of Matrix Converter. To verify the performance of the proposed MOSFET-based Matrix Converter, modulation strategy, and control design methodology, various simulation and experimental results are presented. The experimental results are obtained under operating condition present in an aircraft. The experimental results verify the proposed Matrix Converter provides a reliable power conversion in an aircraft under extreme operating conditions. The results prove the superiority of the proposed Matrix

  6. Transcranial extracellular impedance control (tEIC modulates behavioral performances.

    Directory of Open Access Journals (Sweden)

    Ayumu Matani

    Full Text Available Electric brain stimulations such as transcranial direct current stimulation (tDCS, transcranial random noise stimulation (tRNS, and transcranial alternating current stimulation (tACS electrophysiologically modulate brain activity and as a result sometimes modulate behavioral performances. These stimulations can be viewed from an engineering standpoint as involving an artificial electric source (DC, noise, or AC attached to an impedance branch of a distributed parameter circuit. The distributed parameter circuit is an approximation of the brain and includes electric sources (neurons and impedances (volume conductors. Such a brain model is linear, as is often the case with the electroencephalogram (EEG forward model. Thus, the above-mentioned current stimulations change the current distribution in the brain depending on the locations of the electric sources in the brain. Now, if the attached artificial electric source were to be replaced with a resistor, or even a negative resistor, the resistor would also change the current distribution in the brain. In light of the superposition theorem, which holds for any linear electric circuit, attaching an electric source is different from attaching a resistor; the resistor affects each active electric source in the brain so as to increase (or decrease in some cases of a negative resistor the current flowing out from each source. From an electrophysiological standpoint, the attached resistor can only control the extracellular impedance and never causes forced stimulation; we call this technique transcranial extracellular impedance control (tEIC. We conducted a behavioral experiment to evaluate tEIC and found evidence that it had real-time enhancement and depression effects on EEGs and a real-time facilitation effect on reaction times. Thus, tEIC could be another technique to modulate behavioral performance.

  7. Decoupling Control Design for the Module Suspension Control System in Maglev Train

    Directory of Open Access Journals (Sweden)

    Guang He

    2015-01-01

    Full Text Available An engineering oriented decoupling control method for the module suspension system is proposed to solve the coupling issues of the two levitation units of the module in magnetic levitation (maglev train. According to the format of the system transfer matrix, a modified adjoint transfer matrix based decoupler is designed. Then, a compensated controller is obtained in the light of a desired close loop system performance. Optimization between the performance index and robustness index is also carried out to determine the controller parameters. However, due to the high orders and complexity of the obtained resultant controller, model reduction method is adopted to get a simplified controller with PID structure. Considering the modeling errors of the module suspension system as the uncertainties, experiments have been performed to obtain the weighting function of the system uncertainties. By using this, the robust stability of the decoupled module suspension control system is checked. Finally, the effectiveness of the proposed decoupling design method is validated by simulations and physical experiments. The results illustrate that the presented decoupling design can result in a satisfactory decoupling and better dynamic performance, especially promoting the reliability of the suspension control system in practical engineering application.

  8. Bilingualism modulates dual mechanisms of cognitive control: Evidence from ERPs.

    Science.gov (United States)

    Morales, Julia; Yudes, Carolina; Gómez-Ariza, Carlos J; Bajo, M Teresa

    2015-01-01

    Recent behavioral findings with the AX-Continous Performance Task (AX-CPT; Morales et al., 2013) show that bilinguals only outperform monolinguals under conditions that require the highest adjustment between monitoring (proactive) and inhibitory (reactive) control, which supports the idea that bilingualism modulates the coordination of different control mechanisms. In an ERP experiment we aimed to further investigate the role that bilingualism plays in the dynamic combination of proactive and reactive control in the AX-CPT. Our results strongly indicate that bilingualism facilitates an effective adjustment between both components of cognitive control. First, we replicated previous behavioral results. Second, ERP components indicated that bilingualism influences the conflict monitoring, response inhibition and error monitoring components of control (as indexed by the N2 and P3a elicited by the probe and the error-related negativity following incorrect responses, respectively). Thus, bilinguals exerted higher reactive control than monolinguals but only when they needed to overcome the competing cue-information. These findings join others in suggesting that a better understanding of the cognitive benefits of bilingualism may require consideration of a multi-component perspective. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Validation of Storm Water Management Model Storm Control Measures Modules

    Science.gov (United States)

    Simon, M. A.; Platz, M. C.

    2017-12-01

    EPA's Storm Water Management Model (SWMM) is a computational code heavily relied upon by industry for the simulation of wastewater and stormwater infrastructure performance. Many municipalities are relying on SWMM results to design multi-billion-dollar, multi-decade infrastructure upgrades. Since the 1970's, EPA and others have developed five major releases, the most recent ones containing storm control measures modules for green infrastructure. The main objective of this study was to quantify the accuracy with which SWMM v5.1.10 simulates the hydrologic activity of previously monitored low impact developments. Model performance was evaluated with a mathematical comparison of outflow hydrographs and total outflow volumes, using empirical data and a multi-event, multi-objective calibration method. The calibration methodology utilized PEST++ Version 3, a parameter estimation tool, which aided in the selection of unmeasured hydrologic parameters. From the validation study and sensitivity analysis, several model improvements were identified to advance SWMM LID Module performance for permeable pavements, infiltration units and green roofs, and these were performed and reported herein. Overall, it was determined that SWMM can successfully simulate low impact development controls given accurate model confirmation, parameter measurement, and model calibration.

  10. Modulation of Apoptosis Controls Inhibitory Interneuron Number in the Cortex

    Directory of Open Access Journals (Sweden)

    Myrto Denaxa

    2018-02-01

    Full Text Available Cortical networks are composed of excitatory projection neurons and inhibitory interneurons. Finding the right balance between the two is important for controlling overall cortical excitation and network dynamics. However, it is unclear how the correct number of cortical interneurons (CIs is established in the mammalian forebrain. CIs are generated in excess from basal forebrain progenitors, and their final numbers are adjusted via an intrinsically determined program of apoptosis that takes place during an early postnatal window. Here, we provide evidence that the extent of CI apoptosis during this critical period is plastic and cell-type specific and can be reduced in a cell-autonomous manner by acute increases in neuronal activity. We propose that the physiological state of the emerging neural network controls the activity levels of local CIs to modulate their numbers in a homeostatic manner.

  11. Engine Performance (Section C: Emission Control Systems). Auto Mechanics Curriculum Guide. Module 3. Instructor's Guide.

    Science.gov (United States)

    Rains, Larry

    This engine performance (emission control systems) module is one of a series of competency-based modules in the Missouri Auto Mechanics Curriculum Guide. Topics of this module's five units are: positive crankcase ventilation (PCV) and evaporative emission control systems; exhaust gas recirculation (EGR); air injection and catalytic converters;…

  12. Programmable logic controller optical fibre sensor interface module

    Science.gov (United States)

    Allwood, Gary; Wild, Graham; Hinckley, Steven

    2011-12-01

    Most automated industrial processes use Distributed Control Systems (DCSs) or Programmable Logic Controllers (PLCs) for automated control. PLCs tend to be more common as they have much of the functionality of DCSs, although they are generally cheaper to install and maintain. PLCs in conjunction with a human machine interface form the basis of Supervisory Control And Data Acquisition (SCADA) systems, combined with communication infrastructure and Remote Terminal Units (RTUs). RTU's basically convert different sensor measurands in to digital data that is sent back to the PLC or supervisory system. Optical fibre sensors are becoming more common in industrial processes because of their many advantageous properties. Being small, lightweight, highly sensitive, and immune to electromagnetic interference, means they are an ideal solution for a variety of diverse sensing applications. Here, we have developed a PLC Optical Fibre Sensor Interface Module (OFSIM), in which an optical fibre is connected directly to the OFSIM located next to the PLC. The embedded fibre Bragg grating sensors, are highly sensitive and can detect a number of different measurands such as temperature, pressure and strain without the need for a power supply.

  13. Automated force controller for amplitude modulation atomic force microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Miyagi, Atsushi, E-mail: atsushi.miyagi@inserm.fr, E-mail: simon.scheuring@inserm.fr; Scheuring, Simon, E-mail: atsushi.miyagi@inserm.fr, E-mail: simon.scheuring@inserm.fr [U1006 INSERM, Université Aix-Marseille, Parc Scientifique et Technologique de Luminy, 163 Avenue de Luminy, 13009 Marseille (France)

    2016-05-15

    Atomic Force Microscopy (AFM) is widely used in physics, chemistry, and biology to analyze the topography of a sample at nanometer resolution. Controlling precisely the force applied by the AFM tip to the sample is a prerequisite for faithful and reproducible imaging. In amplitude modulation (oscillating) mode AFM, the applied force depends on the free and the setpoint amplitudes of the cantilever oscillation. Therefore, for keeping the applied force constant, not only the setpoint amplitude but also the free amplitude must be kept constant. While the AFM user defines the setpoint amplitude, the free amplitude is typically subject to uncontrollable drift, and hence, unfortunately, the real applied force is permanently drifting during an experiment. This is particularly harmful in biological sciences where increased force destroys the soft biological matter. Here, we have developed a strategy and an electronic circuit that analyzes permanently the free amplitude of oscillation and readjusts the excitation to maintain the free amplitude constant. As a consequence, the real applied force is permanently and automatically controlled with picoNewton precision. With this circuit associated to a high-speed AFM, we illustrate the power of the development through imaging over long-duration and at various forces. The development is applicable for all AFMs and will widen the applicability of AFM to a larger range of samples and to a larger range of (non-specialist) users. Furthermore, from controlled force imaging experiments, the interaction strength between biomolecules can be analyzed.

  14. An illusion of control modulates the reluctance to tempt fate

    Directory of Open Access Journals (Sweden)

    Chloe L. Swirsky

    2011-10-01

    Full Text Available The tempting fate effect is that the probability of a fateful outcome is deemed higher following an action that ``tempts'' the outcome than in the absence of such an action. In this paper we evaluate the hypothesis that the effect is due to an illusion of control induced by a causal framing of the situation. Causal frames require that the action make a difference to an outcome and that the action precedes the outcome. If an illusion of control modulates the reluctance to tempt fate, then actions that make a difference to well-being and that occur prior to the outcome should tempt fate most strongly. In Experiments 1--3 we varied whether the action makes a difference and the temporal order of action and outcome. In Experiment 4 we tested whether an action can tempt fate if all outcomes are negative. The results of all four experiments supported our hypothesis that the tempting fate effect depends on a causal construal that gives rise to a false sense of control.

  15. Development of an Ethernet enabled microcontroller based module for Superconducting Cyclotron ECR beam line control

    International Nuclear Information System (INIS)

    Chatterjee, M.; Koley, D.; Nabhiraj, P.Y.

    2012-01-01

    An Ethernet enabled control and data acquisition module is developed for remote control and monitoring of the ECR beam line equipment of the Superconducting Cyclotron. The PIC microcontroller based module supports multiple general purpose analog and digital inputs and outputs for interfacing with various equipments and an embedded web server. The remote monitoring and control of the equipment are achieved through the web based user interface. The user authenticated access to control parameters and module configuration parameters ensures the operational safety of the equipment under control. This module is installed in Superconducting Cyclotron ECR beam line for the control and monitoring of vacuum pumping modules, comprising of pumps, gate valves and dual vacuum gauges. The installation of these modules results in a distributed control with localised field cabling and hence better fault diagnosis. (author)

  16. High speed turning of compacted graphite iron using controlled modulation

    Science.gov (United States)

    Stalbaum, Tyler Paul

    Compacted graphite iron (CGI) is a material which emerged as a candidate material to replace cast iron (CI) in the automotive industry for engine block castings. Its thermal and mechanical properties allow the CGI-based engines to operate at higher cylinder pressures and temperatures than CI-based engines, allowing for lower fuel emissions and increased fuel economy. However, these same properties together with the thermomechanical wear mode in the CGI-CBN system result in poor machinability and inhibit CGI from seeing wide spread use in the automotive industry. In industry, machining of CGI is done only at low speeds, less than V = 200 m/min, to avoid encountering rapid wear of the cutting tools during cutting. Studies have suggested intermittent cutting operations such as milling suffer less severe tool wear than continuous cutting. Furthermore, evidence that a hard sulfide layer which forms over the cutting edge in machining CI at high speeds is absent during machining CGI is a major factor in the difference in machinability of these material systems. The present study addresses both of these issues by modification to the conventional machining process to allow intermittent continuous cutting. The application of controlled modulation superimposed onto the cutting process -- modulation-assisted machining (MAM) -- is shown to be quite effective in reducing the wear of cubic boron nitride (CBN) tools when machining CGI at high machining speeds (> 500 m/min). The tool life is at least 20 times greater than found in conventional machining of CGI. This significant reduction in wear is a consequence of reduction in the severity of the tool-work contact conditions with MAM. The propensity for thermochemical wear of CBN is thus reduced. It is found that higher cutting speed (> 700 m/min) leads to lower tool wear with MAM. The MAM configuration employing feed-direction modulation appears feasible for implementation at high speeds and offers a solution to this challenging

  17. Pulsed klystrons with feedback controlled mod-anode modulators

    Energy Technology Data Exchange (ETDEWEB)

    Reass, William A [Los Alamos National Laboratory; Baca, David M [Los Alamos National Laboratory; Jerry, Davis L [Los Alamos National Laboratory; Rees, Daniel E [Los Alamos National Laboratory

    2009-01-01

    This paper describes a fast rise and fall, totem-pole mod-anode modulators for klystron application. Details of these systems as recently installed utilizing a beam switch tube ''on-deck'' and a planar triode ''off-deck'' in a grid-catch feedback regulated configuration will be provided. The grid-catch configuration regulates the klystron mod-anode voltage at a specified set-point during switching as well as providing a control mechanism that flat-top regulates the klystron beam current during the pulse. This flat-topped klystron beam current is maintained while the capacitor bank droops. In addition, we will review more modern on-deck designs using a high gain, high voltage planar triode as a regulating and switching element. These designs are being developed, tested, and implemented for the Los Alamos Neutron Science Center (LANSCE) accelerator refurbishment project, ''LANSCE-R''. An advantage of the planar triode is that the tube can be directly operated with solid state linear components and provides for a very compact design. The tubes are inexpensive compared to stacked semiconductor switching assemblies and also provide a linear control capability. Details of these designs are provided as well as operational and developmental results.

  18. Landslides control the spatial and temporal variation of channel width in southern Taiwan: implications for landscape evolution and cascading hazards in steep, tectonically active landscapes

    Science.gov (United States)

    Yanites, B.; Bregy, J. C.; Carlson, G.; Cataldo, K.; Holahan, M.; Johnston, G.; Mitchell, N. A.; Nelson, A.; Valenza, J.; Wanker, M.

    2017-12-01

    Intense precipitation or seismic events can generate clustered mass movement processes across a landscape. These rare events have significant impacts on the landscape, however, the rarity of such events leads to uncertainty in how these events impact the entire geomorphic system over a range of timescales. Taiwan is a steep, seismically active region and is highly prone to landslide and debris flows, especially when exposed to heavy rainfall events. Typhoon Morakot made landfall in Taiwan in August of 2009, delivering record-breaking rainfall and inducing more than 22,000 landslides in southern Taiwan. The topographic gradient in southern Taiwan leads to spatial variability in landslide susceptibility providing an opportunity to infer the long-term impact of landslides on channel morphology. The availability of pre and post typhoon imagery allows a quantitative reconstruction on the propagating impact of this event on channel width. The pre and post typhoon patterns of channel width to river and hillslope gradients in 20 basins in the study area reveal the importance of cascading hazards from landslides on landscape evolution. Prior to Typhoon Morakot, the river channels in the central part of the study area were about 3-10 times wider than the channels in the south. Aggradation and widening was also a maximum in these basins where hillslope gradients and channel steepness is high. The results further show that the narrowest channels are located where channel steepness is the lowest, an observation inconsistent with a detachment-limited model for river evolution. We infer this pattern is indicative of a strong role of sediment supply, and associated landslide events, on long-term channel evolution. These findings have implications across a range of spatial and temporal scales including understanding the cascade of hazards in steep landscapes and geomorphic interpretation of channel morphology.

  19. Pump and Flow Control Subassembly of Thermal Control Subsystem for Photovoltaic Power Module

    Science.gov (United States)

    Motil, Brian; Santen, Mark A.

    1993-01-01

    The pump and flow control subassembly (PFCS) is an orbital replacement unit (ORU) on the Space Station Freedom photovoltaic power module (PVM). The PFCS pumps liquid ammonia at a constant rate of approximately 1170 kg/hr while providing temperature control by flow regulation between the radiator and the bypass loop. Also, housed within the ORU is an accumulator to compensate for fluid volumetric changes as well as the electronics and firmware for monitoring and control of the photovoltaic thermal control system (PVTCS). Major electronic functions include signal conditioning, data interfacing and motor control. This paper will provide a description of each major component within the PFCS along with performance test data. In addition, this paper will discuss the flow control algorithm and describe how the nickel hydrogen batteries and associated power electronics will be thermally controlled through regulation of coolant flow to the radiator.

  20. Probabilistic Analysis of Crack Width

    Directory of Open Access Journals (Sweden)

    J. Marková

    2000-01-01

    Full Text Available Probabilistic analysis of crack width of a reinforced concrete element is based on the formulas accepted in Eurocode 2 and European Model Code 90. Obtained values of reliability index b seem to be satisfactory for the reinforced concrete slab that fulfils requirements for the crack width specified in Eurocode 2. However, the reliability of the slab seems to be insufficient when the European Model Code 90 is considered; reliability index is less than recommended value 1.5 for serviceability limit states indicated in Eurocode 1. Analysis of sensitivity factors of basic variables enables to find out variables significantly affecting the total crack width.

  1. A deterministic width function model

    Directory of Open Access Journals (Sweden)

    C. E. Puente

    2003-01-01

    Full Text Available Use of a deterministic fractal-multifractal (FM geometric method to model width functions of natural river networks, as derived distributions of simple multifractal measures via fractal interpolating functions, is reported. It is first demonstrated that the FM procedure may be used to simulate natural width functions, preserving their most relevant features like their overall shape and texture and their observed power-law scaling on their power spectra. It is then shown, via two natural river networks (Racoon and Brushy creeks in the United States, that the FM approach may also be used to closely approximate existing width functions.

  2. A Module For Thermal Pest Control In Stored Raw Materials Used In ...

    African Journals Online (AJOL)

    Pests are heterogeneous both in space and time, creating gradients and patterns depending on the prevailing environmental variables. Pest control efforts have utilized manipulations of these variables. This project is ona module for thermal control of pests using the hitherto waste steam from the indusries. The module is an ...

  3. Designing an Electro-Hydraulic Control Module for an Open-Circuit Variable Displacement Pump

    DEFF Research Database (Denmark)

    Pedersen, Henrik Clemmensen; Andersen, Torben Ole; Hansen, Michael Rygaard

    2005-01-01

    , in the form of an electric control signal, under varying working conditions, when having access to engine speed and actual pump pressure. The paper presents a model of both the pump and the control module, along with design considerations on which linear controllers are developed for a worst point......This paper deals with the problem of designing an electric control module for a Sauer-Danfoss Series 45 H-frame open circuit axial piston pump. The purpose of the electric control module is to replace the existing hydro-mechanical (LS) regulator, and enable the pump to follow a reference pressure...

  4. Active control of sound transmission through partitions composed of discretely controlled modules

    Science.gov (United States)

    Leishman, Timothy W.

    This thesis provides a detailed theoretical and experimental investigation of active segmented partitions (ASPs) for the control of sound transmission. ASPs are physically segmented arrays of interconnected acoustically and structurally small modules that are discretely controlled using electronic controllers. Theoretical analyses of the thesis first address physical principles fundamental to ASP modeling and experimental measurement techniques. Next, they explore specific module configurations, primarily using equivalent circuits. Measured normal-incidence transmission losses and related properties of experimental ASPs are determined using plane wave tubes and the two-microphone transfer function technique. A scanning laser vibrometer is also used to evaluate distributed transmitting surface vibrations. ASPs have the inherent potential to provide excellent active sound transmission control (ASTC) through lightweight structures, using very practical control strategies. The thesis analyzes several unique ASP configurations and evaluates their abilities to produce high transmission losses via global minimization of normal transmitting surface vibrations. A novel dual diaphragm configuration is shown to employ this strategy particularly well. It uses an important combination of acoustical actuation and mechano-acoustical segmentation to produce exceptionally high transmission loss (e.g., 50 to 80 dB) over a broad frequency range-including lower audible frequencies. Such performance is shown to be comparable to that produced by much more massive partitions composed of thick layers of steel or concrete and sand. The configuration uses only simple localized error sensors and actuators, permitting effective use of independent single-channel controllers in a decentralized format. This work counteracts the commonly accepted notion that active vibration control of partitions is an ineffective means of controlling sound transmission. With appropriate construction, actuation

  5. High precision laser control of the ATLAS tile-calorimeter module mass production at JINR

    International Nuclear Information System (INIS)

    Batusov, V.; Budagov, Yu.; Flyagin, V.; Khubua, D.; Lomakin, Yu.; Lyablin, M.; Rusakovich, N.; Shabalin, D.; Topilin, N.; Nessi, M.

    2001-01-01

    We present a short description of our last few years experience in the quality control of the ATLAS hadron barrel tile-calorimeter module mass production at JINR. A Laser Measurement System (LMS) proposed and realized in Dubna guarantees a high-precision module assembly. The non-planarity of module size surfaces (1.9x5.6 m) controlled area is well within the required ±0.6 mm tolerance for each of JINR assembled modules. The module assembly technique achieved with the LMS system allows us to deliver to CERN one module every 2 weeks. This laser-based measurement system could be used in future for the control measurement of other large-scale units during the ATLAS assembly

  6. United States Control Module Guidance, Navigation, and Control Subsystem Design Concept

    Science.gov (United States)

    Polites, M. E.; Bartlow, B. E.

    1997-01-01

    Should the Russian Space Agency (RSA) not participate in the International Space Station (ISS) program, then the United States (U.S.) National Aeronautics and Space Administration (NASA) may choose to execute the ISS mission. However, in order to do this, NASA must build two new space vehicles, which must perform the functions that the Russian vehicles and hardware were to perform. These functions include periodic ISS orbit reboost, initial ISS attitude control, and U.S. On-Orbit Segment (USOS) control Moment gyroscope (CMG) momentum desaturation. The two new NASA vehicles that must perform these functions are called the U.S. control module (USCM) and the U.S. resupply module. This paper presents a design concept for the USCM GN&C subsystem, which must play a major role in ISS orbit reboost and initial attitude control, plus USOS CMG momentum desaturation. The proposed concept is structured similar to the USOS GN&C subsystem, by design. It is very robust, in that it allows the USCM to assume a variety of vehicle attitudes and stay power-positive. It has a storage/safe mode that places the USCM in a gravity-gradient orientation and keeps it there for extended periods of time without consuming a great deal of propellant. Simulation results are presented and discussed that show the soundness of the design approach. An equipment list is included that gives detailed information on the baselined GN&C components.

  7. Spherical bodies of constant width

    OpenAIRE

    Lassak, Marek; Musielak, Michał

    2018-01-01

    The intersection $L$ of two different non-opposite hemispheres $G$ and $H$ of a $d$-dimensional sphere $S^d$ is called a lune. By the thickness of $L$ we mean the distance of the centers of the $(d-1)$-dimensional hemispheres bounding $L$. For a hemisphere $G$ supporting a %spherical convex body $C \\subset S^d$ we define ${\\rm width}_G(C)$ as the thickness of the narrowest lune or lunes of the form $G \\cap H$ containing $C$. If ${\\rm width}_G(C) =w$ for every hemisphere $G$ supporting $C$, we...

  8. Intrinsic Sensing and Evolving Internal Model Control of Compact Elastic Module for a Lower Extremity Exoskeleton.

    Science.gov (United States)

    Wang, Likun; Du, Zhijiang; Dong, Wei; Shen, Yi; Zhao, Guangyu

    2018-03-19

    To achieve strength augmentation, endurance enhancement, and human assistance in a functional autonomous exoskeleton, control precision, back drivability, low output impedance, and mechanical compactness are desired. In our previous work, two elastic modules were designed for human-robot interaction sensing and compliant control, respectively. According to the intrinsic sensing properties of the elastic module, in this paper, only one compact elastic module is applied to realize both purposes. Thus, the corresponding control strategy is required and evolving internal model control is proposed to address this issue. Moreover, the input signal to the controller is derived from the deflection of the compact elastic module. The human-robot interaction is considered as the disturbance which is approximated by the output error between the exoskeleton control plant and evolving forward learning model. Finally, to verify our proposed control scheme, several experiments are conducted with our robotic exoskeleton system. The experiment shows a satisfying result and promising application feasibility.

  9. Intrinsic Sensing and Evolving Internal Model Control of Compact Elastic Module for a Lower Extremity Exoskeleton

    Directory of Open Access Journals (Sweden)

    Likun Wang

    2018-03-01

    Full Text Available To achieve strength augmentation, endurance enhancement, and human assistance in a functional autonomous exoskeleton, control precision, back drivability, low output impedance, and mechanical compactness are desired. In our previous work, two elastic modules were designed for human–robot interaction sensing and compliant control, respectively. According to the intrinsic sensing properties of the elastic module, in this paper, only one compact elastic module is applied to realize both purposes. Thus, the corresponding control strategy is required and evolving internal model control is proposed to address this issue. Moreover, the input signal to the controller is derived from the deflection of the compact elastic module. The human–robot interaction is considered as the disturbance which is approximated by the output error between the exoskeleton control plant and evolving forward learning model. Finally, to verify our proposed control scheme, several experiments are conducted with our robotic exoskeleton system. The experiment shows a satisfying result and promising application feasibility.

  10. Intrinsic Sensing and Evolving Internal Model Control of Compact Elastic Module for a Lower Extremity Exoskeleton

    Science.gov (United States)

    Wang, Likun; Du, Zhijiang; Dong, Wei; Shen, Yi; Zhao, Guangyu

    2018-01-01

    To achieve strength augmentation, endurance enhancement, and human assistance in a functional autonomous exoskeleton, control precision, back drivability, low output impedance, and mechanical compactness are desired. In our previous work, two elastic modules were designed for human–robot interaction sensing and compliant control, respectively. According to the intrinsic sensing properties of the elastic module, in this paper, only one compact elastic module is applied to realize both purposes. Thus, the corresponding control strategy is required and evolving internal model control is proposed to address this issue. Moreover, the input signal to the controller is derived from the deflection of the compact elastic module. The human–robot interaction is considered as the disturbance which is approximated by the output error between the exoskeleton control plant and evolving forward learning model. Finally, to verify our proposed control scheme, several experiments are conducted with our robotic exoskeleton system. The experiment shows a satisfying result and promising application feasibility. PMID:29562684

  11. EPICS IOC module development and implementation for the ISTTOK machine subsystem operation and control

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Paulo, E-mail: pricardofc@ipfn.ist.utl.pt [Associacao EURATOM/IST, Instituto de Plasmas e Fusao Nuclear-Laboratorio Associado, Instituto Superior Tecnico, P-1049-001 Lisboa (Portugal); Duarte, Andre; Pereira, Tiago; Carvalho, Bernardo; Sousa, Jorge; Fernandes, Horacio [Associacao EURATOM/IST, Instituto de Plasmas e Fusao Nuclear-Laboratorio Associado, Instituto Superior Tecnico, P-1049-001 Lisboa (Portugal); Correia, Carlos [Grupo de Electronica e Instrumentacao-Centro de Instrumentacao, Departamento de Fisica, Universidade de Coimbra, P-3004-516 Coimbra (Portugal); Goncalves, Bruno; Varandas, Carlos [Associacao EURATOM/IST, Instituto de Plasmas e Fusao Nuclear-Laboratorio Associado, Instituto Superior Tecnico, P-1049-001 Lisboa (Portugal)

    2011-10-15

    This paper presents a developed, tested and integrated EPICS IOC (I/O controller) module solution for the ISTTOK tokamak machine operation and control for the vacuum and gas injection systems. The work is organized in two software layers which communicate through a serial RS-232 communication protocol. The first software layer is an EPICS IOC module running as a computer server application capable of receiving requests from remote or local clients providing driver interface to the system by forwarding requested commands and receiving system and control operation status. The second software layer is the firmware running in Microchip dsPIC microcontroller modules which performs the interface from RS-232 optical fiber serial protocol to EPICS IOC module. The dsPIC module communicates to the ISTTOK tokamak sensors and actuators via RS-485 and is programmed with a new protocol developed for this purpose that allows EPICS IOC module command sending/receiving, machine operation control and monitoring and system status information. Communication between EPICS IOC module and clients is achieved via a TCP/IP and UDP protocol referred as Channel Access. In addition, the EPICS IOC module provides user client applications access allowing operators to perform remote or local monitoring, operation and control.

  12. Cross-layer combining of power control and adaptive modulation with truncated ARQ for cognitive radios

    Institute of Scientific and Technical Information of China (English)

    CHENG Shi-lun; YANG Zhen

    2008-01-01

    To maximize throughput and to satisfy users' requirements in cognitive radios, a cross-layer optimization problem combining adaptive modulation and power control at the physical layer and truncated automatic repeat request at the medium access control layer is proposed. Simulation results show the combination of power control, adaptive modulation, and truncated automatic repeat request can regulate transmitter powers and increase the total throughput effectively.

  13. Improvement The Transmission Efficiency For Wireless Packet Communication Systems Using Automatic Control for power And Time Slot Width Of Slotted Non persistent ISMA Protocol

    Directory of Open Access Journals (Sweden)

    Saad M. Hardan

    2013-05-01

    Full Text Available In packed communication systems which use a protocol, the protocol should perform the allocation of channels such that the transmission channel is used efficiently. Efficiency is usually measured in terms of channel throughput and the average transmission  delay. The Slotted Nonpersistent ISMA protocol is one of random access protocols used in packed communication systems. In this research a Slotted Nonpersistent ISMA protocol Model with automatic control for power and time slot is proposed. the suggested algorithm enable the base station(access point to control  the protocol time slot length and  transmission power in a dynamic way to control the normalized propagation delay d and to maintain all the uplink signals in the limit of captured power threshold (capture ratio in order to control the  throughput and the average transmission delay of the communication system by an automatic method. the computer simulation results  confirm the activity of the  proposed algorithm for increasing the  throughput and decreasing the average transmission delay by an accepted ratios.

  14. Development of Active External Network Topology Module for Floodlight SDN Controller

    Directory of Open Access Journals (Sweden)

    A. A. Noskov

    2015-01-01

    Full Text Available Traditional network architecture is inflexible and complicated. This observation has led to a paradigm shift towards software-defined networking (SDN, where network management level is separated from data forwarding level. This change was made possible by control plane transfer from the switching equipment to software modules that run on a dedicated server, called the controller (or network operating system, or network applications, that work with this controller. Methods of representation, storage and communication interfaces with network topology elements are the most important aspects of network operating systems available to SDN user because performance of some key controller modules is heavily dependent on internal representation of the network topology. Notably, firewall and routing modules are examples of such modules. This article describes the methods used for presentation and storage of network topologies, as well as interface to the corresponding Floodlight modules. An alternative algorithm has been suggested and developed for message exchange conveying network topology alterations between the controller and network applications. Proposed algorithm makes implementation of module alerting based on subscription to the relevant events. API for interaction between controller and network applications has been developed. This algorithm and API formed the base for Topology Tracker module capable to inform network applications about the changes that had occurred in the network topology and also stores compact representation of the network to speed up the interaction process.

  15. Project T.E.A.M. (Technical Education Advancement Modules). Introduction to Statistical Process Control.

    Science.gov (United States)

    Billings, Paul H.

    This instructional guide, one of a series developed by the Technical Education Advancement Modules (TEAM) project, is a 6-hour introductory module on statistical process control (SPC), designed to develop competencies in the following skill areas: (1) identification of the three classes of SPC use; (2) understanding a process and how it works; (3)…

  16. A double-panel active segmented partition module using decoupled analog feedback controllers: numerical model.

    Science.gov (United States)

    Sagers, Jason D; Leishman, Timothy W; Blotter, Jonathan D

    2009-06-01

    Low-frequency sound transmission has long plagued the sound isolation performance of lightweight partitions. Over the past 2 decades, researchers have investigated actively controlled structures to prevent sound transmission from a source space into a receiving space. An approach using active segmented partitions (ASPs) seeks to improve low-frequency sound isolation capabilities. An ASP is a partition which has been mechanically and acoustically segmented into a number of small individually controlled modules. This paper provides a theoretical and numerical development of a single ASP module configuration, wherein each panel of the double-panel structure is independently actuated and controlled by an analog feedback controller. A numerical model is developed to estimate frequency response functions for the purpose of controller design, to understand the effects of acoustic coupling between the panels, to predict the transmission loss of the module in both passive and active states, and to demonstrate that the proposed ASP module will produce bidirectional sound isolation.

  17. The segmented non-uniform dielectric module design for uniformity control of plasma profile in a capacitively coupled plasma chamber

    International Nuclear Information System (INIS)

    Xia, Huanxiong; Xiang, Dong; Yang, Wang; Mou, Peng

    2014-01-01

    Low-temperature plasma technique is one of the critical techniques in IC manufacturing process, such as etching and thin-film deposition, and the uniformity greatly impacts the process quality, so the design for the plasma uniformity control is very important but difficult. It is hard to finely and flexibly regulate the spatial distribution of the plasma in the chamber via controlling the discharge parameters or modifying the structure in zero-dimensional space, and it just can adjust the overall level of the process factors. In the view of this problem, a segmented non-uniform dielectric module design solution is proposed for the regulation of the plasma profile in a CCP chamber. The solution achieves refined and flexible regulation of the plasma profile in the radial direction via configuring the relative permittivity and the width of each segment. In order to solve this design problem, a novel simulation-based auto-design approach is proposed, which can automatically design the positional sequence with multi independent variables to make the output target profile in the parameterized simulation model approximate the one that users preset. This approach employs an idea of quasi-closed-loop control system, and works in an iterative mode. It starts from initial values of the design variable sequences, and predicts better sequences via the feedback of the profile error between the output target profile and the expected one. It never stops until the profile error is narrowed in the preset tolerance

  18. DSP Based Direct Torque Control of Permanent Magnet Synchronous Motor (PMSM) using Space Vector Modulation (DTC-SVM)

    DEFF Research Database (Denmark)

    Swierczynski, Dariusz; Kazmierkowski, Marian P.; Blaabjerg, Frede

    2002-01-01

    DSP Based Direct Torque Control of Permanent Magnet Synchronous Motor (PMSM) using Space Vector Modulation (DTC-SVM)......DSP Based Direct Torque Control of Permanent Magnet Synchronous Motor (PMSM) using Space Vector Modulation (DTC-SVM)...

  19. fpga controller design and simulation of a portable dough mixing

    African Journals Online (AJOL)

    modelled and simulated with Matlab/Simulink. Synthesizable VHDL ... Keywords: FPGA, VHDL, PID controller, Pulse Width Modulation, Full H-Bridge DC motor driver. 1. ... and (b) to simulate the control process in a virtual environment, using.

  20. Improvement and amplification of the I modulate CDSM (control sub device modulates) of the system DECADES

    International Nuclear Information System (INIS)

    Turtos Carbonell, Leonor

    1999-01-01

    The present work consists on the improvement and amplification of the module CDSM of the one System DECADES starting from the experience acquired in the use of the same one. It was implemented The calculation for all the Technologies of Reduction of Emissions (TRE) included in the one System for all the levels of foreseen analysis (it plants, chain and Electroenergetic Systems ), a case of test was evaluated with all the TRE and those were validated results obtained with available data in the reference bibliography

  1. [Statistical process control applied to intensity modulated radiotherapy pretreatment controls with portal dosimetry].

    Science.gov (United States)

    Villani, N; Gérard, K; Marchesi, V; Huger, S; François, P; Noël, A

    2010-06-01

    The first purpose of this study was to illustrate the contribution of statistical process control for a better security in intensity modulated radiotherapy (IMRT) treatments. This improvement is possible by controlling the dose delivery process, characterized by pretreatment quality control results. So, it is necessary to put under control portal dosimetry measurements (currently, the ionisation chamber measurements were already monitored by statistical process control thanks to statistical process control tools). The second objective was to state whether it is possible to substitute ionisation chamber with portal dosimetry in order to optimize time devoted to pretreatment quality control. At Alexis-Vautrin center, pretreatment quality controls in IMRT for prostate and head and neck treatments were performed for each beam of each patient. These controls were made with an ionisation chamber, which is the reference detector for the absolute dose measurement, and with portal dosimetry for the verification of dose distribution. Statistical process control is a statistical analysis method, coming from industry, used to control and improve the studied process quality. It uses graphic tools as control maps to follow-up process, warning the operator in case of failure, and quantitative tools to evaluate the process toward its ability to respect guidelines: this is the capability study. The study was performed on 450 head and neck beams and on 100 prostate beams. Control charts, showing drifts, both slow and weak, and also both strong and fast, of mean and standard deviation have been established and have shown special cause introduced (manual shift of the leaf gap of the multileaf collimator). Correlation between dose measured at one point, given with the EPID and the ionisation chamber has been evaluated at more than 97% and disagreement cases between the two measurements were identified. The study allowed to demonstrate the feasibility to reduce the time devoted to

  2. Statistical process control applied to intensity modulated radiotherapy pretreatment controls with portal dosimetry

    International Nuclear Information System (INIS)

    Villani, N.; Noel, A.; Villani, N.; Gerard, K.; Marchesi, V.; Huger, S.; Noel, A.; Francois, P.

    2010-01-01

    Purpose The first purpose of this study was to illustrate the contribution of statistical process control for a better security in intensity modulated radiotherapy (I.M.R.T.) treatments. This improvement is possible by controlling the dose delivery process, characterized by pretreatment quality control results. So, it is necessary to put under control portal dosimetry measurements (currently, the ionisation chamber measurements were already monitored by statistical process control thanks to statistical process control tools). The second objective was to state whether it is possible to substitute ionisation chamber with portal dosimetry in order to optimize time devoted to pretreatment quality control. Patients and methods At Alexis-Vautrin center, pretreatment quality controls in I.M.R.T. for prostate and head and neck treatments were performed for each beam of each patient. These controls were made with an ionisation chamber, which is the reference detector for the absolute dose measurement, and with portal dosimetry for the verification of dose distribution. Statistical process control is a statistical analysis method, coming from industry, used to control and improve the studied process quality. It uses graphic tools as control maps to follow-up process, warning the operator in case of failure, and quantitative tools to evaluate the process toward its ability to respect guidelines: this is the capability study. The study was performed on 450 head and neck beams and on 100 prostate beams. Results Control charts, showing drifts, both slow and weak, and also both strong and fast, of mean and standard deviation have been established and have shown special cause introduced (manual shift of the leaf gap of the multi-leaf collimator). Correlation between dose measured at one point, given with the E.P.I.D. and the ionisation chamber has been evaluated at more than 97% and disagreement cases between the two measurements were identified. Conclusion The study allowed to

  3. On the maximal diphoton width

    CERN Document Server

    Salvio, Alberto; Strumia, Alessandro; Urbano, Alfredo

    2016-01-01

    Motivated by the 750 GeV diphoton excess found at LHC, we compute the maximal width into $\\gamma\\gamma$ that a neutral scalar can acquire through a loop of charged fermions or scalars as function of the maximal scale at which the theory holds, taking into account vacuum (meta)stability bounds. We show how an extra gauge symmetry can qualitatively weaken such bounds, and explore collider probes and connections with Dark Matter.

  4. Performance Investigation of Air Velocity Effects on PV Modules under Controlled Conditions

    Directory of Open Access Journals (Sweden)

    Muzaffar Ali

    2017-01-01

    Full Text Available Junction temperature of PV modules is one of the key parameters on which the performance of PV modules depends. In the present work, an experimental investigation was carried out to analyze the effects of air velocity on the performance of two PV modules, that is, monocrystalline silicon and polycrystalline silicon under the controlled conditions of a wind tunnel in the presence of an artificial solar simulator. The parameters investigated include the surface temperature variation, power output, and efficiency of PV modules under varying air velocity from near zero (indoor lab. conditions to 15 m/s. Additionally, the results were also determined at two different module angular positions: at 0° angle, that is, parallel to air direction and at 10° angle with the direction of coming air to consider the effects of tilt angles. Afterwards, the thermal analysis of the modules was performed using Ansys-Fluent in which junction temperature and heat flux of modules were determined by applying appropriate boundary conditions, such as air velocity, heat flux, and solar radiation. Finally, the numerical results are compared with the experiment in terms of junction temperatures of modules and good agreement was found. Additionally, the results showed that the maximum module temperature drops by 17.2°C and the module efficiency and power output increased from 10 to 12% with increasing air velocity.

  5. Design of Simulink module for dynamic reactivity simulation of marine reactor automatic control rod

    International Nuclear Information System (INIS)

    Chen Zhiyun; Luo Lei; Chen Wenzhen; Gui Xuewen

    2010-01-01

    The power of marine reactor varies frequently and acutely, which induces the frequent and acute adjustment of the automatic control rod. According to the characteristics of marine reactor and the problem of improper control rod reactivity insertion in previous literatures, the Simulink module for dynamic reactivity simulation of automatic control rod was designed and adopted as a sub-module of Simulink program for the fast calculation of the physical and thermal parameters of marine reactor. A typical dynamic process of the marine reactor was used as the benchmark, which indicates that the designed Simulink module is capable of the dynamic simulation of automatic control rod position and reactivity, and is adequate to the fast calculation of physic and thermal parameters. The Simulink module is of significant meaning to the simulation of the dynamic process of marine reactor and the fast calculation of the operating parameters. (authors)

  6. Prefrontal cortical neuregulin-ErbB modulation of inhibitory control in rats

    NARCIS (Netherlands)

    Loos, M.; Schetters, Dustin; Hoogeland, Myrthe; Spijker, S.; de Vries, Taco J; Pattij, Tommy

    2016-01-01

    Impulse control disturbances are key features of various neuropsychiatric and neurological disorders, such as attention-deficit/hyperactivity disorder, drug addiction, Parkinson disease and schizophrenia. Whereas over the last years accumulating evidence has highlighted monoaminergic modulation of

  7. Software requirements specification for the program analysis and control system risk management module

    International Nuclear Information System (INIS)

    SCHAEFER, J.C.

    1999-01-01

    TWR Program Analysis and Control System Risk Module is used to facilitate specific data processes surrounding the Risk Management program of the Tank Waste Retrieval environment. This document contains the Risk Management system requirements of the database system

  8. On the (Frequency) Modulation of Coupled Oscillator Arrays in Phased Array Beam Control

    Science.gov (United States)

    Pogorzelski, R.; Acorn, J.; Zawadzki, M.

    2000-01-01

    It has been shown that arrays of voltage controlled oscillators coupled to nearest neighbors can be used to produce useful aperture phase distributions for phased array antennas. However, placing information of the transmitted signal requires that the oscillations be modulated.

  9. Pulsewidth modulated DC-to-DC power conversion circuits, dynamics, and control designs

    CERN Document Server

    Choi, Byungcho

    2013-01-01

    This is the definitive reference for anyone involved in pulsewidth modulated DC-to-DC power conversion Pulsewidth Modulated DC-to-DC Power Conversion: Circuits, Dynamics, and Control Designs provides engineers, researchers, and students in the power electronics field with comprehensive and complete guidance to understanding pulsewidth modulated (PWM) DC-to-DC power converters. Presented in three parts, the book addresses the circuitry and operation of PWM DC-to-DC converters and their dynamic characteristics, along with in-depth discussions of control design of PWM DC-to

  10. Masses, widths, and leptonic widths of the higher upsilon resonances

    International Nuclear Information System (INIS)

    Lovelock, D.M.J.; Horstkotte, J.E.; Klopfenstein, C.

    1985-01-01

    The masses, total widths, and leptonic widths of three triplet s-wave bb-bar states UPSILON(4S), UPSILON(5S), and UPSILON(6S) are determined from measurements of the e + e - annihilation cross section into hadrons for 10.55< W<11.25 GeV. The resonances are identified from potential model results and their properties are obtained with the help of a simplified coupled-channels calculation. We find M(4S) = 10.577 GeV, GAMMA(4S) = 25 MeV, GAMMA/sub e/e(4S) = 0.28 keV; M(5S) = 10.845 GeV, GAMMA(5S) = 110 MeV, GAMMA/sub e/e(5S) = 0.37 keV; M(6S) = 11.02 GeV, GAMMA(6S) = 90 MeV, GAMMA/sub e/e(6S) = 0.16 keV

  11. Masses, widths and leptonic widths of the higher upsilon resonances

    International Nuclear Information System (INIS)

    Klopfenstein, C.; Lovelock, D.M.J.; Horstkotte, J.E.

    1985-01-01

    The masses, total widths and leptonic widths of three triplet s-wave bb-bar states Υ(4S), Υ(5S) and Υ(6S) are determined by unfolding the cross section features observed in the hadronic cross section in the √s region betweeen 10.55 to 11.25 GeV. Both the identification of the resonances and the deduction of their properties rely on the validity of potential models' description of heavy quarkonium states which lie close (<0.6 GeV) to the open flavor threshold. The authors find M(4S) = 10.5774 +- 0.0008 GeV, Γ(4S) = 23 +- 2.3 MeV, Γ/sub ee/(4S) = 0.28 +- 0.04 keV; M(5S) = 10.845 +- 0.02 GeV, Γ(5S) = 110 +- 15 MeV, Γ/sub ee/(5S) = 0.37 +- 0.06 keV; M(6S) = 11.02 +- 0.03 GeV, Γ(6S) = 90 +- 20 MeV, Γ/sub ee/(6S) = 0.16 +- 0.04 keV. All errors are statistical only

  12. Machine Shop. Module 8: CNC (Computerized Numerical Control). Instructor's Guide.

    Science.gov (United States)

    Crosswhite, Dwight

    This document consists of materials for a five-unit course on the following topics: (1) safety guidelines; (2) coordinates and dimensions; (3) numerical control math; (4) programming for numerical control machines; and (5) setting and operating the numerical control machine. The instructor's guide begins with a list of competencies covered in the…

  13. Control of a Dual-Stator Flux-Modulated Motor for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Xinhua Guo

    2016-07-01

    Full Text Available This paper presents the control strategies for a novel dual-stator flux-modulated (DSFM motor for application in electric vehicles (EVs. The DSFM motor can be applied to EVs because of its simple winding structure, high reliability, and its use of two stators and rotating modulation steels in the air gap. Moreover, it outperforms conventional brushless doubly-fed machines in terms of control performance. Two stator-current-oriented vector controls with different excitation in the primary winding, direct and alternating current excitation, are designed, simulated, and evaluated on a custom-made DSFM prototype allowing the decoupled control of torque. The stable speed response and available current characteristics strongly validate the feasibility of the two control methods. Furthermore, the proposed control methods can be employed in other applications of flux-modulated motors.

  14. Reliability Analysis on NPP's Safety-Related Control Module with Field Data

    International Nuclear Information System (INIS)

    Lee, Sang Yong; Jung, Jae Hyun; Kim, Seong Hun

    2006-01-01

    The automatic control systems used in nuclear power plant (NPP) consists of numerous control modules that can be considered to be a network of components various complex ways. The control modules require relatively high reliability than industrial electronic products. Reliability prediction provides the rational basis of system designs and also provides the safety significance of system operations. The aim of this paper is to minimize the deficiencies of the traditional reliability prediction method calculation using the available field return data. This way is possible to do more realistic reliability assessment. SAMCHANG Enterprise Company (SEC) has established database containing high quality data at the module and component level from module maintenance in NPP. On the basis of these, this paper compares results that add failure record (field data) to Telcordia-SR-332 reliability prediction model with MIL-HDBK-217F prediction results

  15. Pengaruh Prosentase Etanol terhadap Torsi dan Emisi Motor Indirect Injection dengan Memodifikasi Engine Control Module

    Directory of Open Access Journals (Sweden)

    Hadi Rahmad

    2016-10-01

    Full Text Available This research present the torque and exhaust emission level from four stroke indirect injection fuel system engine. An engine fueled by ethanol gasoline blend. The original Engine Controle Module injected lean mixture into Combustion Chamber. Lean Mixture decreased Torque drastically. Therefore, the Engine Controle Module was modified to produce stoichiometric mixture. Injector was controlled by digital pulse of Fuel Controller. Ethanol was added into gasoline 0% - 100% at 1500 rpm-5000 rpm. The result demonstrate that increasing ethanol concentration into gasoline fuel system, decreasing Torque, and CO, HC, CO2 emission. By increasing ethanol concentration also increase CO2 emission to 34.6%.

  16. Tourniquet pressures: strap width and tensioning system widths.

    Science.gov (United States)

    Wall, Piper L; Coughlin, Ohmar; Rometti, Mary; Birkholz, Sarah; Gildemaster, Yvonne; Grulke, Lisa; Sahr, Sheryl; Buising, Charisse M

    2014-01-01

    Pressure distribution over tourniquet width is a determinant of pressure needed for arterial occlusion. Different width tensioning systems could result in arterial occlusion pressure differences among nonelastic strap designs of equal width. Ratcheting Medical Tourniquets (RMTs; m2 inc., http://www.ratcheting buckles.com) with a 1.9 cm-wide (Tactical RMT) or 2.3 cm-wide (Mass Casualty RMT) ladder were directly compared (16 recipients, 16 thighs and 16 upper arms for each tourniquetx2). Then, RMTs were retrospectively compared with the windlass Combat Application Tourniquet (C-A-T ["CAT"], http://combattourniquet.com) with a 2.5 cm-wide internal tensioning strap. Pressure was measured with an air-filled No. 1 neonatal blood pressure cuff under each 3.8 cm-wide tourniquet. RMT circumferential pressure distribution was not uniform. Tactical RMT pressures were not higher, and there were no differences between the RMTs in the effectiveness, ease of use ("97% easy"), or discomfort. However, a difference did occur regarding tooth skipping of the pawl during ratchet advancement: it occurred in 1 of 64 Tactical RMT applications versus 27 of 64 Mass Casualty RMT applications. CAT and RMT occlusion pressures were frequently over 300 mmHg. RMT arm occlusion pressures (175-397 mmHg), however, were lower than RMT thigh occlusion pressures (197-562 mmHg). RMT effectiveness was better with 99% reached occlusion and 1% lost occlusion over 1 minute versus the CAT with 95% reached occlusion and 28% lost occlusion over 1 minute. RMT muscle tension changes (up to 232 mmHg) and pressure losses over 1 minute (24±11 mmHg arm under strap to 40±12 mmHg thigh under ladder) suggest more occlusion losses may have occurred if tourniquet duration was extended. The narrower tensioning system Tactical RMT has better performance characteristics than the Mass Casualty RMT. The 3.8 cm-wide RMTs have some pressure and effectiveness similarities and differences compared with the CAT. Clinically

  17. Calibration and control modules for gamma-ray borehole loggers

    International Nuclear Information System (INIS)

    1983-01-01

    A calibration pad for quantitative evaluation of gamma-ray logs, developed and constructed by CNEA is described. The facility is composed of a set of mineralized modules with which it is intended to reproduce the natural variable conditions found in boreholes drilled for uranium mineral exploration, such as the ore concentration, rock's density and porosity, water content, etc. The facility is able to operate under different radiometric models, as follow: 1) gross-count gamma-ray models; 2) gamma-spectrometer models; 3) neutronic-fission models, and 4) models for determination of magnetic susceptibility, density, neutron-neutron, etc. The gathered information allows the adequate quantitative radiometric evaluation of the ore bodies crossed by exploration holes, and also allows the correlation of gamma-ray logs obtained by different logger-equipments. The paper includes the description of the project development and the standards established for the facility's operation. (M.E.L.) [es

  18. Social exclusion modulates priorities of attention allocation in cognitive control

    Science.gov (United States)

    Xu, Mengsi; Li, Zhiai; Diao, Liuting; Zhang, Lijie; Yuan, Jiajin; Ding, Cody; Yang, Dong

    2016-08-01

    Many studies have investigated how exclusion affects cognitive control and have reported inconsistent results. However, these studies usually treated cognitive control as a unitary concept, whereas it actually involved two main sub-processes: conflict detection and response implementation. Furthermore, existing studies have focused primarily on exclusion’s effects on conscious cognitive control, while recent studies have shown the existence of unconscious cognitive control. Therefore, the present study investigated whether and how exclusion affects the sub-processes underlying conscious and unconscious cognitive control differently. The Cyberball game was used to manipulate social exclusion and participants subsequently performed a masked Go/No-Go task during which event-related potentials were measured. For conscious cognitive control, excluded participants showed a larger N2 but smaller P3 effects than included participants, suggesting that excluded people invest more attention in conscious conflict detection, but less in conscious inhibition of impulsive responses. However, for unconscious cognitive control, excluded participants showed a smaller N2 but larger P3 effects than included participants, suggesting that excluded people invest less attention in unconscious conflict detection, but more in unconscious inhibition of impulsive responses. Together, these results suggest that exclusion causes people to rebalance attention allocation priorities for cognitive control according to a more flexible and adaptive strategy.

  19. Methodology Series Module 2: Case-control Studies.

    Science.gov (United States)

    Setia, Maninder Singh

    2016-01-01

    Case-Control study design is a type of observational study. In this design, participants are selected for the study based on their outcome status. Thus, some participants have the outcome of interest (referred to as cases), whereas others do not have the outcome of interest (referred to as controls). The investigator then assesses the exposure in both these groups. The investigator should define the cases as specifically as possible. Sometimes, definition of a disease may be based on multiple criteria; thus, all these points should be explicitly stated in case definition. An important aspect of selecting a control is that they should be from the same 'study base' as that of the cases. We can select controls from a variety of groups. Some of them are: General population; relatives or friends; and hospital patients. Matching is often used in case-control control studies to ensure that the cases and controls are similar in certain characteristics, and it is a useful technique to increase the efficiency of the study. Case-Control studies can usually be conducted relatively faster and are inexpensive - particularly when compared with cohort studies (prospective). It is useful to study rare outcomes and outcomes with long latent periods. This design is not very useful to study rare exposures. Furthermore, they may also be prone to certain biases - selection bias and recall bias.

  20. A Performance Improvement of Power Supply Module for Safety-related Controller

    International Nuclear Information System (INIS)

    Kim, Jong-Kyun; Yun, Dong-Hwa; Hwang, Sung-Jae; Lee, Myeong-Kyun; Yoo, Kwan-Woo

    2015-01-01

    In this paper, in relation to voltage shortage state when power supply module is a slave mode, the performance improvement by modifying a PFC(Power Factor Correction) circuit is presented. With the modification of the PFC circuit, the performance improvement in respect of the voltage shortage state when the power supply module is a slave mode is checked. As a result, POSAFE-Q PLC can ensure the stability with the redundant power supply module. The purpose of this paper is to improve the redundant performance of power supply module(NSPS-2Q). It is one of components in POSAFE-Q which is a PLC(Programmable Logic Controller) that has been developed for the evaluation of safety-related. Power supply module provides a stable power in order that POSAFE-Q can be operated normally. It is possible to be mounted two power supply modules in POSAFE-Q for a redundant(Master/Slave) function. So that even if a problem occurs in one power supply module, another power supply module will provide a power to POSAFE-Q stably

  1. Periodic equivalence ratio modulation method and apparatus for controlling combustion instability

    Science.gov (United States)

    Richards, George A.; Janus, Michael C.; Griffith, Richard A.

    2000-01-01

    The periodic equivalence ratio modulation (PERM) method and apparatus significantly reduces and/or eliminates unstable conditions within a combustion chamber. The method involves modulating the equivalence ratio for the combustion device, such that the combustion device periodically operates outside of an identified unstable oscillation region. The equivalence ratio is modulated between preselected reference points, according to the shape of the oscillation region and operating parameters of the system. Preferably, the equivalence ratio is modulated from a first stable condition to a second stable condition, and, alternatively, the equivalence ratio is modulated from a stable condition to an unstable condition. The method is further applicable to multi-nozzle combustor designs, whereby individual nozzles are alternately modulated from stable to unstable conditions. Periodic equivalence ratio modulation (PERM) is accomplished by active control involving periodic, low frequency fuel modulation, whereby low frequency fuel pulses are injected into the main fuel delivery. Importantly, the fuel pulses are injected at a rate so as not to affect the desired time-average equivalence ratio for the combustion device.

  2. A Performance Improvement of Power Supply Module for Safety-related Controller

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong-Kyun; Yun, Dong-Hwa; Hwang, Sung-Jae; Lee, Myeong-Kyun; Yoo, Kwan-Woo [PONUTech Co., Seoul (Korea, Republic of)

    2015-10-15

    In this paper, in relation to voltage shortage state when power supply module is a slave mode, the performance improvement by modifying a PFC(Power Factor Correction) circuit is presented. With the modification of the PFC circuit, the performance improvement in respect of the voltage shortage state when the power supply module is a slave mode is checked. As a result, POSAFE-Q PLC can ensure the stability with the redundant power supply module. The purpose of this paper is to improve the redundant performance of power supply module(NSPS-2Q). It is one of components in POSAFE-Q which is a PLC(Programmable Logic Controller) that has been developed for the evaluation of safety-related. Power supply module provides a stable power in order that POSAFE-Q can be operated normally. It is possible to be mounted two power supply modules in POSAFE-Q for a redundant(Master/Slave) function. So that even if a problem occurs in one power supply module, another power supply module will provide a power to POSAFE-Q stably.

  3. Electrically and spatially controllable PDLC phase gratings for diffraction and modulation of laser beams

    Energy Technology Data Exchange (ETDEWEB)

    Hadjichristov, Georgi B., E-mail: georgibh@issp.bas.bg [Laboratory of Optics and Spectroscopy, Georgi Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee Blvd., BG-1784 Sofia (Bulgaria); Marinov, Yordan G.; Petrov, Alexander G. [Laboratory of Biomolecular Layers, Georgi Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee Blvd., BG-1784 Sofia, Bulgaria (Bulgaria)

    2016-03-25

    We present a study on electrically- and spatially-controllable laser beam diffraction, electrooptic (EO) phase modulation, as well as amplitude-frequency EO modulation by single-layer microscale polymer-dispersed liquid crystal (PDLC) phase gratings (PDLC SLPGs) of interest for device applications. PDLC SLPGs were produced from nematic liquid crystal (LC) E7 in photo-curable NOA65 polymer. The wedge-formed PDLC SLPGs have a continuously variable thickness (2–25 µm). They contain LC droplets of diameters twice as the layer thickness, with a linear-gradient size distribution along the wedge. By applying alternating-current (AC) electric field, the PDLC SLPGs produce efficient: (i) diffraction splitting of transmitted laser beams; (ii) spatial redistribution of diffracted light intensity; (iii) optical phase modulation; (iv) amplitude-frequency modulation, all controllable by the driven AC field and the droplet size gradient.

  4. Controlled porosity solubility modulated osmotic pump tablets of gliclazide.

    Science.gov (United States)

    Banerjee, Arti; Verma, P R P; Gore, Subhash

    2015-06-01

    A system that can deliver drug at a controlled rate is very important for the treatment of various chronic diseases such as diabetes, asthma, and heart disease. Poorly water-soluble drug with pH-dependent solubility such as gliclazide (GLZ) offers challenges in the controlled-release formulation because of low dissolution rate and poor bioavailability. Solid dispersion (SD) of GLZ consisted of hydroxypropyl cellulose (HPC-SSL) as a polymeric solubilizer was manufactured by hot melt extrusion (HME) technology. Then, controlled porosity osmotic pump (CPOP) tablet of gliclazide was designed to deliver drug in a controlled manner up to 16 h. The developed formulation was optimized for type and level of pore former and coating weight gain. The optimized formulation was found to exhibit zero order kinetics independent of pH and agitation speed but depends on osmotic pressure of dissolution media indicated that mechanism of drug release was osmotic pressure. The in vivo performance prediction of developed formulation using convolution approach revealed that the developed formulation was superior to the existing marketed extended-release formulation in terms of attaining steady state plasma levels and indicated adequate exposure in translating hypoglycemic response. The prototype solubilization method combined with controlled porosity osmotic pump based technique could provide a unique way to increase dissolution rate and bioavailability of many poorly water-soluble, narrow therapeutic index drugs used in diabetes, cardiovascular diseases, etc.

  5. Comparison of Arch Width Changes Following Orthodontic ...

    African Journals Online (AJOL)

    2015-11-21

    Nov 21, 2015 ... Materials and Methods: The study was conducted with pre- and post-treatment digital models from ... or posterior arch width following orthodontic treatment ..... premolar extraction cases show significant arch width increases in ...

  6. Calcium channel modulation as a target in chronic pain control.

    Science.gov (United States)

    Patel, Ryan; Montagut-Bordas, Carlota; Dickenson, Anthony H

    2018-06-01

    Neuropathic pain remains poorly treated for large numbers of patients, and little progress has been made in developing novel classes of analgesics. To redress this issue, ziconotide (Prialt™) was developed and approved as a first-in-class synthetic version of ω-conotoxin MVIIA, a peptide blocker of Ca v 2.2 channels. Unfortunately, the impracticalities of intrathecal delivery, low therapeutic index and severe neurological side effects associated with ziconotide have restricted its use to exceptional circumstances. Ziconotide exhibits no state or use-dependent block of Ca v 2.2 channels; activation state-dependent blockers were hypothesized to circumvent the side effects of state-independent blockers by selectively targeting high-frequency firing of nociceptive neurones in chronic pain states, thus alleviating aberrant pain but not affecting normal sensory transduction. Unfortunately, numerous drugs, including state-dependent calcium channel blockers, have displayed efficacy in preclinical models but have subsequently been disappointing in clinical trials. In recent years, it has become more widely acknowledged that trans-aetiological sensory profiles exist amongst chronic pain patients and may indicate similar underlying mechanisms and drug sensitivities. Heterogeneity amongst patients, a reliance on stimulus-evoked endpoints in preclinical studies and a failure to utilize translatable endpoints, all are likely to have contributed to negative clinical trial results. We provide an overview of how electrophysiological and operant-based assays provide insight into sensory and affective aspects of pain in animal models and how these may relate to chronic pain patients in order to improve the bench-to-bedside translation of calcium channel modulators. This article is part of a themed section on Recent Advances in Targeting Ion Channels to Treat Chronic Pain. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175

  7. Design of embedded control system for high-power tetrode modulator

    International Nuclear Information System (INIS)

    Tu Rui; Yao Lieying; Xuan Weimin

    2010-01-01

    The design of embedded control system for the high-power tetrode modulator and its test results are given. This control system is a closed-loop feedback system based on the DSP and embedded into the high-voltage modulator. A new modified method of VF fiber transmission is used in the embedded control system. The new method improves the speed of the transmission of feedback system. The results of the experiment demonstrate that the embedded feedback control system greatly increases the response speed of the whole system and improves the performance of the high-power tetrode on the HL-2A tokamak. This embedded feedback control system greatly simplifies the complexity of the original centralized control system. The operation of the control system is reliable. (authors)

  8. Optimal Backlight Modulation With Crosstalk Control in Stereoscopic Display

    DEFF Research Database (Denmark)

    Jiao, Liangbao; Shu, Xiao; Cheng, Yong

    2014-01-01

    . A simple closed-form approximation of the optimization problem can be easily employed and solved in real time on LCD control hardware. Simulation results show that the proposed OBM algorithm provides the same or higher luminance while reducing the crosstalk by 60% compared with the other tested methods....

  9. EPICS device support module as ATCA system manager for the ITER fast plant system controller

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Paulo F., E-mail: pricardofc@ipfn.ist.utl.pt [Associação EURATOM/IST, Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico – Universidade Técnica de Lisboa, Lisboa (Portugal); Santos, Bruno; Gonçalves, Bruno; Carvalho, Bernardo B.; Sousa, Jorge; Rodrigues, A.P.; Batista, António J.N.; Correia, Miguel; Combo, Álvaro [Associação EURATOM/IST, Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico – Universidade Técnica de Lisboa, Lisboa (Portugal); Correia, Carlos M.B.A. [Centro de Instrumentação, Departamento de Física, Universidade de Coimbra, Coimbra (Portugal); Varandas, Carlos A.F. [Associação EURATOM/IST, Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico – Universidade Técnica de Lisboa, Lisboa (Portugal)

    2013-10-15

    Highlights: ► In Nuclear Fusion, demanding security and high-availability requirements call for redundancy to be available. ► ATCA based Nuclear Fusion Systems are composed by several electronic and mechanical component. ► Control and monitoring of ATCA electronic systems are recommended. ► ITER Fast Plant System Controller Project CODAC system prototype. ► EPICS device support module as External ATCA system manager solution. -- Abstract: This paper presents an Enhanced Physics and Industrial Control System (EPICS) device support module for the International Thermonuclear Experimental Reactor (ITER) Fast Plant System Controller (FPSC) project based in Advanced Telecommunications Computing Architecture (ATCA) specification. The developed EPICS device support module provides an External System Manager (ESM) solution for monitoring and control the ITER FPSC ATCA shelf system and data acquisition boards in order to take proper action and report problems to a control room operator or high level management unit in case of any system failure occurrence. EPICS device support module acts as a Channel Access (CA) server to report problems and publish ATCA system data information to the control room operator, high level management unit or other CA network clients such as Control System Studio Operator Interfaces (CSS OPIs), Best Ever Alarm System Toolkit (BEAST), Best Ever Archive Utility (BEAUTY) or other CA client applications. EPICS device support module communicates with the ATCA Shelf manager (ShM) using HTTP protocol to send and receive commands through POST method in order to get and set system and shelf components properties such as fan speeds measurements, temperatures readings, module status and ATCA boards acquisition and configuration parameters. All system properties, states, commands and parameters are available through the EPICS device support module CA server in EPICS Process Variables (PV) and signals format. ATCA ShM receives the HTTP protocol

  10. MATLAB Stability and Control Toolbox Trim and Static Stability Module

    Science.gov (United States)

    Kenny, Sean P.; Crespo, Luis

    2012-01-01

    MATLAB Stability and Control Toolbox (MASCOT) utilizes geometric, aerodynamic, and inertial inputs to calculate air vehicle stability in a variety of critical flight conditions. The code is based on fundamental, non-linear equations of motion and is able to translate results into a qualitative, graphical scale useful to the non-expert. MASCOT was created to provide the conceptual aircraft designer accurate predictions of air vehicle stability and control characteristics. The code takes as input mass property data in the form of an inertia tensor, aerodynamic loading data, and propulsion (i.e. thrust) loading data. Using fundamental nonlinear equations of motion, MASCOT then calculates vehicle trim and static stability data for the desired flight condition(s). Available flight conditions include six horizontal and six landing rotation conditions with varying options for engine out, crosswind, and sideslip, plus three take-off rotation conditions. Results are displayed through a unique graphical interface developed to provide the non-stability and control expert conceptual design engineer a qualitative scale indicating whether the vehicle has acceptable, marginal, or unacceptable static stability characteristics. If desired, the user can also examine the detailed, quantitative results.

  11. Mathematical analysis and coordinated current allocation control in battery power module systems

    Science.gov (United States)

    Han, Weiji; Zhang, Liang

    2017-12-01

    As the major energy storage device and power supply source in numerous energy applications, such as solar panels, wind plants, and electric vehicles, battery systems often face the issue of charge imbalance among battery cells/modules, which can accelerate battery degradation, cause more energy loss, and even incur fire hazard. To tackle this issue, various circuit designs have been developed to enable charge equalization among battery cells/modules. Recently, the battery power module (BPM) design has emerged to be one of the promising solutions for its capability of independent control of individual battery cells/modules. In this paper, we propose a new current allocation method based on charging/discharging space (CDS) for performance control in BPM systems. Based on the proposed method, the properties of CDS-based current allocation with constant parameters are analyzed. Then, real-time external total power requirement is taken into account and an algorithm is developed for coordinated system performance control. By choosing appropriate control parameters, the desired system performance can be achieved by coordinating the module charge balance and total power efficiency. Besides, the proposed algorithm has complete analytical solutions, and thus is very computationally efficient. Finally, the efficacy of the proposed algorithm is demonstrated using simulations.

  12. Front-end module readout and control electronics for the PHENIX Multiplicity Vertex Detector

    International Nuclear Information System (INIS)

    Ericson, M.N.; Allen, M.D.; Boissevain, J.

    1997-11-01

    Front-end module (FEM) readout and control are implemented as modular, high-density, reprogrammable functions in the PHENIX Multiplicity Vertex Detector. FEM control is performed by the heap manager, an FPGA-based circuit in the FEM unit. Each FEM has 256 channels of front-end electronics, readout, and control, all located on an MCM. Data readout, formatting, and control are performed by the heap manager along with 4 interface units that reside outside the MVD detector cylinder. This paper discusses the application of a generic heap manager and the addition of 4 interface module types to meet the specific control and data readout needs of the MVD. Unit functioning, interfaces, timing, data format, and communication rates will be discussed in detail. In addition, subsystem issues regarding mode control, serial architecture and functions, error handling, and FPGA implementation and programming will be presented

  13. System control for the modulated 252Cf source ''Shuffler''

    International Nuclear Information System (INIS)

    Stephens, M.M.

    1975-06-01

    The design and theory of operation of the control chassis for a 252 Cf nondestructive assay system are described. This system repetitively transfers a 252 Cf source from the irradiation region to a shielded position before measuring the delayed neutrons. The design criteria for the system were: rapid movement and precise positioning of the 252 Cf source, precise positioning of the sample, and very accurate timing of the irradiate and count cycles. To achieve these results crystal oscillators were used for timing, and stepping motors were used to position the sample and the source. (U.S.)

  14. RCT: Module 2.08, Radiological Source Control, Course 8774

    Energy Technology Data Exchange (ETDEWEB)

    Hillmer, Kurt T. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-08-10

    radioactive source is material used for its emitted radiation. Sources are sealed or unsealed and are classified as accountable or exempt. Radioactive sources are used for response checks, functional checks, and the calibration of instruments and monitors to traceable standards. To ensure the safety and welfare of all personnel, it is important to maintain control of radioactive sources to minimize the potential for the spread of contamination, unnecessary exposure to personnel, loss or theft, and improper disposal. This course will prepare the student with the skills necessary for RCT qualification by passing quizzes, tests, and the RCT Comprehensive Phase 1, Unit 2 Examination (TEST 27566) and will provide in-the-field skills.

  15. Control-grid electron gun as a source of modulated electron beam for a collective accelerator

    International Nuclear Information System (INIS)

    Bakumenko, A.A.; Belikov, V.V.; Zvyagintsev, A.V.; Lyul'chenko, V.I.; Lymar', A.G.; Martynenko, P.A.; Suryadnyj, A.V.

    1989-01-01

    Structure is described and experimental results of investigations into an electron gun with transverse beam compression and control grid are presented. The pulse trailing edge is formed by a sectioned discharger. A modulated electron beam with the following parameters: 110 keV beam energy, 70 A current amplitude, 3-8 MHz modulation frequency, 100% modulation depth, ≅8-6 mm minimal beam diameter, ≅ 10μs pulse duration, 3% pulse top non-uniformity, more than 200 compression degree is obtained when introducing the positive feedback in auto-generator regime to the gun supply circuit. Further it is supposed to use the developed electron gun for heavy ion acceleration by a field of space charge of a modulated electron beam in a corrugated liner. It should be underlined that power supply of such an accelerator does not require powerful outside HF generator. 5 refs.; 1 fig

  16. Shape control of slack space reflectors using modulated solar pressure.

    Science.gov (United States)

    Borggräfe, Andreas; Heiligers, Jeannette; Ceriotti, Matteo; McInnes, Colin R

    2015-07-08

    The static deflection profile of a large spin-stabilized space reflector because of solar radiation pressure acting on its surface is investigated. Such a spacecraft consists of a thin reflective circular film, which is deployed from a supporting hoop structure in an untensioned, slack manner. This paper investigates the use of a variable reflectivity distribution across the surface to control the solar pressure force and hence the deflected shape. In this first analysis, the film material is modelled as one-dimensional slack radial strings with no resistance to bending or transverse shear, which enables a semi-analytic derivation of the nominal deflection profile. An inverse method is then used to find the reflectivity distribution that generates a specific, for example, parabolic deflection shape of the strings. Applying these results to a parabolic reflector, short focal distances can be obtained when large slack lengths of the film are employed. The development of such optically controlled reflector films enables future key mission applications such as solar power collection, radio-frequency antennae and optical telescopes.

  17. Application of Space Vector Modulation in Direct Torque Control of PMSM

    Directory of Open Access Journals (Sweden)

    Michal Malek

    2008-01-01

    Full Text Available The paper deals with an improvement of direct torque control method for permanent magnet synchronous motor drives. Electrical torque distortion of the machine under original direct torque control is relatively high and if proper measures are taken it can be substantially decreased. The proposed solution here is to combine direct torque control with the space vector modulation technique. Such approach can eliminate torque distortion while preserving the simplicity of the original method.

  18. Influence of diffuse goiter on tracheal width

    International Nuclear Information System (INIS)

    Baik, Sung Mo; Shon, Hyung Sun; Kim, Choon Yul; Bahk, Yong Whee

    1980-01-01

    The radioisotopic scanning of the thyroid gland is well established method of demonstrating morphology of the thyroid gland and is used to measure the size, area and weight of thyroid gland. The purpose of this investigation is to observe the various effects of goiter to the regional trachea. Both radioisotopic scanning and roentgenogram were taken at the same time to evaluate size, area and weight of the thyroid glands, as well as to measure the width of soft tissue structure of the neck and the regional trachea in normal and goitrous patients. The clinical materials consisted of normal thyroid group for control (46 cases), diffuse simple goiter group (76 cases) and Graves' disease group (59 cases). The results were as follows; 1. The goiter causes some narrowing of the regional trachea to various degree which is not necessarily reflective of the size of goiter. 2. The goiter may increase the width of retrotracheal soft tissue space. 3. The lateral roentgenogram of the neck appear very useful in estimating the thyroid gland three dimensionally and the effect of goiter to the regional trachea

  19. Projective Synchronization in Modulated Time-Delayed Chaotic Systems Using an Active Control Approach

    International Nuclear Information System (INIS)

    Feng Cun-Fang; Wang Ying-Hai

    2011-01-01

    Projective synchronization in modulated time-delayed systems is studied by applying an active control method. Based on the Lyapunov asymptotical stability theorem, the controller and sufficient condition for projective synchronization are calculated analytically. We give a general method with which we can achieve projective synchronization in modulated time-delayed chaotic systems. This method allows us to adjust the desired scaling factor arbitrarily. The effectiveness of our method is confirmed by using the famous delay-differential equations related to optical bistable or hybrid optical bistable devices. Numerical simulations fully support the analytical approach. (general)

  20. Distributed Bragg grating frequency control in metallic nano lasers

    NARCIS (Netherlands)

    Marell, M.J.H.; Hill, M.T.

    2010-01-01

    We show that Bragg gratings can be readily incorporated into metallic nano-lasers which exploit waveguides with semiconductor cores, via modulation of the waveguide width. This provides a simple way to implement laser wavelength control.

  1. Application of EASY5 and MMS modules to BWR controller design

    International Nuclear Information System (INIS)

    Carmichael, L.A.; Rayes, L.; Yasutake, T.

    1987-01-01

    The application of EPRI's MMS Library and BCS' EASY5 simulation language to the design of a digital feedwater control system for the Monticello Boiling Water Nuclear Power Plant is discussed. In order to first design and then verify the digital feedwater controller algorithms, a digital simulation model of the Monticello plant was constructed using a combination of custom designed modules, existing MMS two-phase library modules, and standard modules available in the EASY5 library. Details of the process models, namely the BWR nuclear steam supply system, the steamline piping, and the feedwater piping are described in a companion paper. Details of the models for the existing BWR turbine pressure inlet pressure control and recirculation flow control system are described. These models are required to be operational during the transient analysis portion of the feedwater controller design verification, since they interact strongly with the reactor steam flow and water level. The design of the digital feedwater flow control loop is described. Its design is of particular interest because it requires consideration of control loop interaction and is, therefore, a simple example of multivariable non-interacting control design

  2. Experimental Learning of Digital Power Controller for Photovoltaic Module Using Proteus VSM

    Directory of Open Access Journals (Sweden)

    Abhijit V. Padgavhankar

    2014-01-01

    Full Text Available The electric power supplied by photovoltaic module depends on light intensity and temperature. It is necessary to control the operating point to draw the maximum power of photovoltaic module. This paper presents the design and implementation of digital power converters using Proteus software. Its aim is to enhance student’s learning for virtual system modeling and to simulate in software for PIC microcontroller along with the hardware design. The buck and boost converters are designed to interface with the renewable energy source that is PV module. PIC microcontroller is used as a digital controller, which senses the PV electric signal for maximum power using sensors and output voltage of the dc-dc converter and according to that switching pulse is generated for the switching of MOSFET. The implementation of proposed system is based on learning platform of Proteus virtual system modeling (VSM and the experimental results are presented.

  3. Development and implementation of quality control strategies for CMS silicon strip tracker modules

    CERN Document Server

    Dirkes, Guido

    The LHC will explore physics at the energy frontier and will address many open questions in particle physics, like the search for the Higgs boson or Supersymmetry. For both high resolution track and vertex reconstruction is vital. The CMS silicon tracker consists of 15232 detector modules. Production and assembly of these will span two and a half years period, during which the quality control chain has to ensure functionality and reliability of the modules produced. The CMS group in Karlsruhe will produce and qualify 1600 modules. Therefore automatic test systems are developed and test strategies are worked out. Already during the RnD phase, first prototype tests were performed and some weak points of the design were uncovered. Two test stations are built. One focuses on a fast functionality test, including an active thermal cycle. The other focuses on debugging and repair requirements, including additional test options with lasers, radioactive sources, probes and infrared LEDs. For quality control measuremen...

  4. A Voltage Modulated DPC Approach for Three-Phase PWM Rectifier

    DEFF Research Database (Denmark)

    Gui, Yonghao; Li, Mingshen; Lu, Jinghang

    2018-01-01

    In this paper, a voltage modulated direct power control for three-phase pulse-width modulated rectifier is proposed. With the suggested method, the differential equations describing the rectifier dynamics are changing from a linear time-varying system into a linear time-invariant one. In this way...

  5. Optimal feedback control successfully explains changes in neural modulations during experiments with brain-machine interfaces

    Directory of Open Access Journals (Sweden)

    Miriam eZacksenhouse

    2015-05-01

    Full Text Available Recent experiments with brain-machine-interfaces (BMIs indicate that the extent of neural modulations increased abruptly upon starting to operate the interface, and especially after the monkey stopped moving its hand. In contrast, neural modulations that are correlated with the kinematics of the movement remained relatively unchanged. Here we demonstrate that similar changes are produced by simulated neurons that encode the relevant signals generated by an optimal feedback controller during simulated BMI experiments. The optimal feedback controller relies on state estimation that integrates both visual and proprioceptive feedback with prior estimations from an internal model. The processing required for optimal state estimation and control were conducted in the state-space, and neural recording was simulated by modeling two populations of neurons that encode either only the estimated state or also the control signal. Spike counts were generated as realizations of doubly stochastic Poisson processes with linear tuning curves. The model successfully reconstructs the main features of the kinematics and neural activity during regular reaching movements. Most importantly, the activity of the simulated neurons successfully reproduces the observed changes in neural modulations upon switching to brain control. Further theoretical analysis and simulations indicate that increasing the process noise during normal reaching movement results in similar changes in neural modulations. Thus we conclude that the observed changes in neural modulations during BMI experiments can be attributed to increasing process noise associated with the imperfect BMI filter, and, more directly, to the resulting increase in the variance of the encoded signals associated with state estimation and the required control signal.

  6. Optimal feedback control successfully explains changes in neural modulations during experiments with brain-machine interfaces.

    Science.gov (United States)

    Benyamini, Miri; Zacksenhouse, Miriam

    2015-01-01

    Recent experiments with brain-machine-interfaces (BMIs) indicate that the extent of neural modulations increased abruptly upon starting to operate the interface, and especially after the monkey stopped moving its hand. In contrast, neural modulations that are correlated with the kinematics of the movement remained relatively unchanged. Here we demonstrate that similar changes are produced by simulated neurons that encode the relevant signals generated by an optimal feedback controller during simulated BMI experiments. The optimal feedback controller relies on state estimation that integrates both visual and proprioceptive feedback with prior estimations from an internal model. The processing required for optimal state estimation and control were conducted in the state-space, and neural recording was simulated by modeling two populations of neurons that encode either only the estimated state or also the control signal. Spike counts were generated as realizations of doubly stochastic Poisson processes with linear tuning curves. The model successfully reconstructs the main features of the kinematics and neural activity during regular reaching movements. Most importantly, the activity of the simulated neurons successfully reproduces the observed changes in neural modulations upon switching to brain control. Further theoretical analysis and simulations indicate that increasing the process noise during normal reaching movement results in similar changes in neural modulations. Thus, we conclude that the observed changes in neural modulations during BMI experiments can be attributed to increasing process noise associated with the imperfect BMI filter, and, more directly, to the resulting increase in the variance of the encoded signals associated with state estimation and the required control signal.

  7. Project T.E.A.M. (Technical Education Advancement Modules). Advanced Statistical Process Control.

    Science.gov (United States)

    Dunlap, Dale

    This instructional guide, one of a series developed by the Technical Education Advancement Modules (TEAM) project, is a 20-hour advanced statistical process control (SPC) and quality improvement course designed to develop the following competencies: (1) understanding quality systems; (2) knowing the process; (3) solving quality problems; and (4)…

  8. Coherent Control of Photofragment Distributions Using Laser Phase Modulation in the Weak-Field Limit

    DEFF Research Database (Denmark)

    Garcia-Vela, Alberto; Henriksen, Niels Engholm

    2015-01-01

    The possibility of quantum interference control of the final state distributions of photodissociation fragments by means of pure phase modulation of the pump laser pulse in the weak-field regime is demonstrated theoretically for the first time. The specific application involves realistic wave pac...

  9. Electrical Procedures and Environmental Control Systems. Building Maintenance. Module IV. Instructor's Guide.

    Science.gov (United States)

    Sloan, Garry

    This curriculum guide, one of six modules keyed to the building maintenance competency profile developed by industry and education professionals, provides materials for two units on electrical procedures and environmental control systems. Unit 1, on electrical procedures, includes the following lessons: electrical safety; troubleshooting and…

  10. Controlled delivery of ropinirole hydrochloride through skin using modulated iontophoresis and microneedles.

    Science.gov (United States)

    Singh, Neha D; Banga, Ajay K

    2013-05-01

    The objective of this study was to investigate the effect of modulated current application using iontophoresis- and microneedle-mediated delivery on transdermal permeation of ropinirole hydrochloride. AdminPatch® microneedles and microchannels formed by them were characterized by scanning electron microscopy, dye staining and confocal microscopy. In vitro permeation studies were carried out using Franz diffusion cells, and skin extraction was used to quantify drug in underlying skin. Effect of microneedle pore density and ions in donor formulation was studied. Active enhancement techniques, continuous iontophoresis (74.13 ± 2.20 µg/cm(2)) and microneedles (66.97 ± 10.39 µg/cm(2)), significantly increased the permeation of drug with respect to passive delivery (8.25 ± 2.41 µg/cm(2)). Modulated iontophoresis could control the amount of drug delivered at a given time point with the highest flux being 5.12 ± 1.70 µg/cm(2)/h (5-7 h) and 5.99 ± 0.81 µg/cm(2)/h (20-22 h). Combination of modulated iontophoresis and microneedles (46.50 ± 6.46 µg/cm(2)) showed significantly higher delivery of ropinirole hydrochloride compared to modulated iontophoresis alone (84.91 ± 9.21 µg/cm(2)). Modulated iontophoresis can help in maintaining precise control over ropinirole hydrochloride delivery for dose titration in Parkinson's disease therapy and deliver therapeutic amounts over a suitable patch area and time.

  11. Cyclic pitch for the control of wind turbine noise amplitude modulation

    DEFF Research Database (Denmark)

    Bertagnolio, Franck; Aagaard Madsen, Helge; Fischer, Andreas

    2014-01-01

    Using experimental data acquired during a wind turbine measurement campaign, it is shown that amplitude modulation of aerodynamic noise can be generated by the rotating blades in conjunction with the atmospheric wind shear. As an attempt to alleviate this phenomenon, a control strategy is designed...... if such a strategy is to be implemented on an actual wind turbine, though at the expense of an increased wear and tear of the pitch control system....

  12. Impact on learning of an e-learning module on leukaemia: a randomised controlled trial.

    Science.gov (United States)

    Morgulis, Yuri; Kumar, Rakesh K; Lindeman, Robert; Velan, Gary M

    2012-05-28

    e-learning resources may be beneficial for complex or conceptually difficult topics. Leukaemia is one such topic, yet there are no reports on the efficacy of e-learning for leukaemia. This study compared the learning impact on senior medical students of a purpose-built e-learning module on leukaemia, compared with existing online resources. A randomised controlled trial was performed utilising volunteer senior medical students. Participants were randomly allocated to Study and Control groups. Following a pre-test on leukaemia administered to both groups, the Study group was provided with access to the new e-learning module, while the Control group was directed to existing online resources. A post-test and an evaluation questionnaire were administered to both groups at the end of the trial period. Study and Control groups were equivalent in gender distribution, mean academic ability, pre-test performance and time studying leukaemia during the trial. The Study group performed significantly better than the Control group in the post-test, in which the group to which the students had been allocated was the only significant predictor of performance. The Study group's evaluation of the module was overwhelmingly positive. A targeted e-learning module on leukaemia had a significant effect on learning in this cohort, compared with existing online resources. We believe that the interactivity, dialogic feedback and integration with the curriculum offered by the e-learning module contributed to its impact. This has implications for e-learning design in medicine and other disciplines.

  13. Impact on learning of an e-learning module on leukaemia: a randomised controlled trial

    Directory of Open Access Journals (Sweden)

    Morgulis Yuri

    2012-05-01

    Full Text Available Abstract Background e-learning resources may be beneficial for complex or conceptually difficult topics. Leukaemia is one such topic, yet there are no reports on the efficacy of e-learning for leukaemia. This study compared the learning impact on senior medical students of a purpose-built e-learning module on leukaemia, compared with existing online resources. Methods A randomised controlled trial was performed utilising volunteer senior medical students. Participants were randomly allocated to Study and Control groups. Following a pre-test on leukaemia administered to both groups, the Study group was provided with access to the new e-learning module, while the Control group was directed to existing online resources. A post-test and an evaluation questionnaire were administered to both groups at the end of the trial period. Results Study and Control groups were equivalent in gender distribution, mean academic ability, pre-test performance and time studying leukaemia during the trial. The Study group performed significantly better than the Control group in the post-test, in which the group to which the students had been allocated was the only significant predictor of performance. The Study group’s evaluation of the module was overwhelmingly positive. Conclusions A targeted e-learning module on leukaemia had a significant effect on learning in this cohort, compared with existing online resources. We believe that the interactivity, dialogic feedback and integration with the curriculum offered by the e-learning module contributed to its impact. This has implications for e-learning design in medicine and other disciplines.

  14. Impact on learning of an e-learning module on leukaemia: a randomised controlled trial

    Science.gov (United States)

    2012-01-01

    Background e-learning resources may be beneficial for complex or conceptually difficult topics. Leukaemia is one such topic, yet there are no reports on the efficacy of e-learning for leukaemia. This study compared the learning impact on senior medical students of a purpose-built e-learning module on leukaemia, compared with existing online resources. Methods A randomised controlled trial was performed utilising volunteer senior medical students. Participants were randomly allocated to Study and Control groups. Following a pre-test on leukaemia administered to both groups, the Study group was provided with access to the new e-learning module, while the Control group was directed to existing online resources. A post-test and an evaluation questionnaire were administered to both groups at the end of the trial period. Results Study and Control groups were equivalent in gender distribution, mean academic ability, pre-test performance and time studying leukaemia during the trial. The Study group performed significantly better than the Control group in the post-test, in which the group to which the students had been allocated was the only significant predictor of performance. The Study group’s evaluation of the module was overwhelmingly positive. Conclusions A targeted e-learning module on leukaemia had a significant effect on learning in this cohort, compared with existing online resources. We believe that the interactivity, dialogic feedback and integration with the curriculum offered by the e-learning module contributed to its impact. This has implications for e-learning design in medicine and other disciplines. PMID:22640463

  15. Novel zero voltage transition pulse width modulation flyback converter

    Science.gov (United States)

    Adib, Ehsan; Farzanehfard, Hosein

    2010-09-01

    In this article, a new zero voltage (ZV) transition flyback converter is introduced which uses a simple auxiliary circuit. In this converter, ZV switching condition is achieved for the converter switch while zero current switching condition is attained for the auxiliary switch. There is no additional voltage and current stress on the main switch. Main diode, auxiliary circuit voltage and current ratings are low. The proposed converter is analysed and design procedure is discussed. The presented experimental results of a prototype converter justify the theoretical analysis.

  16. Optimized Pulse Width Modulation for transformerless active-NPC inverters

    DEFF Research Database (Denmark)

    Achilladelis, Nikolaos; Koutroulis, Eftichios; Blaabjerg, Frede

    2014-01-01

    The transformerless DC/AC inverter topologies are employed in Photovoltaic systems in order to improve the power conversion efficiency, power density and cost. The Active-Neutral Point Clamped (Active-NPC) transformerless inverters have the advantage of achieving better thermal balance among thei...

  17. Using the local positioning system based on Pulse Width Modulation ...

    African Journals Online (AJOL)

    There are many ways to estimate the location of a moving object. One way is to determine its location using a GPS which calculates longitude and latitude of the object by the data received by the satellites rotating around the earth. However, there are no devices to recover calculated inherent errors and have an appropriate ...

  18. CAMAC module control from the TPA-1001/i by means of the FOCAL programming language

    International Nuclear Information System (INIS)

    Angelov, A.Kh.; Dubovik, L.V.

    1977-01-01

    The possibility of using FOCAL programming language to control CAMAC modules by minicomputer is considered. This language allows to make effective changes in the program and reduce the time necessary for writing and running programmes. To address CAMAC modules a packet of CAMAC subroutines from the CAMAC-tr A/i software is included into FOCAL language, its operational possibilities and linguistic peculiarities being completely preserved. A big fast memory enables one to add three additional functions to the function list of FOCAL language. An example is given illustrating the use of these functions

  19. Design development of the Apollo command and service module thrust vector attitude control systems

    Science.gov (United States)

    Peters, W. H.

    1978-01-01

    Development of the Apollo thrust vector control digital autopilot (TVC DAP) was summarized. This is the control system that provided pitch and yaw attitude control during velocity change maneuvers using the main rocket engine on the Apollo service module. A list of ten primary functional requirements for this control system are presented, each being subordinate to a more general requirement appearing earlier on the list. Development process functions were then identified and the essential information flow paths were explored. This provided some visibility into the particular NASA/contractor interface, as well as relationships between the many individual activities.

  20. Randomized controlled trial of a computer-based module to improve contraceptive method choice.

    Science.gov (United States)

    Garbers, Samantha; Meserve, Allison; Kottke, Melissa; Hatcher, Robert; Ventura, Alicia; Chiasson, Mary Ann

    2012-10-01

    Unintended pregnancy is common in the United States, and interventions are needed to improve contraceptive use among women at higher risk of unintended pregnancy, including Latinas and women with low educational attainment. A three-arm randomized controlled trial was conducted at two family planning sites serving low-income, predominantly Latina populations. The trial tested the efficacy of a computer-based contraceptive assessment module in increasing the proportion of patients choosing an effective method of contraception (women per year, typical use). Participants were randomized to complete the module and receive tailored health materials, to complete the module and receive generic health materials, or to a control condition. In intent-to-treat analyses adjusted for recruitment site (n=2231), family planning patients who used the module were significantly more likely to choose an effective contraceptive method: 75% among those who received tailored materials [odds ratio (OR)=1.56; 95% confidence interval (CI): 1.23-1.98] and 78% among those who received generic materials (OR=1.74; 95% CI: 1.35-2.25), compared to 65% among control arm participants. The findings support prior research suggesting that patient-centered interventions can positively influence contraceptive method choice. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Chirp-free direct modulation of 550 nm emission in Er3+ -Doped Fluoroindate glass by nonlinear feedback control

    Science.gov (United States)

    Cai, Runyu; Thitsa, Makhin; Bluiett, Althea; Brown, Ei; Hommerich, Uwe

    2017-06-01

    We propose a direct modulation method with nonlinear feedback controller which can produce chirp-free modulation of the output pulse without bulky external modulators. This work reports the design of the controller which, via a feedback loop, varies and controls the pump rate in real time by automatically adjusting the pump power to precisely modulate the emission of 550 nm in Er3+ -doped Fluoroindate glass under 1.48 μm pumping. In this interdisciplinary paper, well established theoretical tools from nonlinear control theory are applied to the dynamical system of the laser material in order to produce the desired output of the laser. The controller is simulated in MATLAB Simulink and the simulation results show that our technique yields precise modulation of the output intensity without frequency chirping. Results on both theoretical analysis of the control methodology and simulation are presented.

  2. Using nonlinearity and spatiotemporal property modulation to control effective structural properties: dynamic rods

    DEFF Research Database (Denmark)

    Thomsen, Jon Juel; Blekhman, Iliya I.

    2007-01-01

    What are the effective properties of a generally nonlinear material or structure, whose local properties are modulated in both space and time? It has been suggested to use spatiotemporal modulation of structural properties to create materials and structures with adjustable effective properties......, and to call these dynamic materials or spatiotemporal composites. Also, according to theoretical predictions, structural nonlinearity enhances the possibilities of achieving specific effective properties. For example, with an elastic rod having cubical elastic nonlinearities, it seems possible to control......, and exemplified. Then simple approximate analytical expressions are derived for the effective wave speed and natural frequencies for one-dimensional wave propagation in a nonlinear elastic rod, where the spatiotemporal modulation is imposed as a high-frequency standing wave, supposed to be given. Finally the more...

  3. A compact, smart Langmuir Probe control module for MAST-Upgrade

    Science.gov (United States)

    Lovell, J.; Stephen, R.; Bray, S.; Naylor, G.; Elmore, S.; Willett, H.; Peterka, M.; Dimitrova, M.; Havranek, A.; Hron, M.; Sharples, R.

    2017-11-01

    A new control module for the MAST-Upgrade Langmuir Probe system has been developed. It is based on a Xilinx Zynq FPGA, which allows for excellent configurability and ease of retrieving data. The module is capable of arbitrary bias voltage waveform generation, and digitises current and voltage readings from 16 probes. The probes are biased and measured one at a time in a time multiplexed fashion, with the multiplexing sequence completely configurable. In addition, simultaneous digitisation of the floating potential of all unbiased probes is possible. A suite of these modules, each coupled with a high voltage amplifier, enables biasing and digitisation of 640 Langmuir Probes in the MAST-Upgrade Super-X divertor. The system has been successfully tested on the York Linear Plasma Device and on the COMPASS tokamak. It will be installed on MAST-Upgrade ready for operations in 2018.

  4. Frontal eye fields control attentional modulation of alpha and gamma oscillations in contralateral occipitoparietal cortex.

    Science.gov (United States)

    Marshall, Tom R; O'Shea, Jacinta; Jensen, Ole; Bergmann, Til O

    2015-01-28

    Covertly directing visuospatial attention produces a frequency-specific modulation of neuronal oscillations in occipital and parietal cortices: anticipatory alpha (8-12 Hz) power decreases contralateral and increases ipsilateral to attention, whereas stimulus-induced gamma (>40 Hz) power is boosted contralaterally and attenuated ipsilaterally. These modulations must be under top-down control; however, the control mechanisms are not yet fully understood. Here we investigated the causal contribution of the human frontal eye field (FEF) by combining repetitive transcranial magnetic stimulation (TMS) with subsequent magnetoencephalography. Following inhibitory theta burst stimulation to the left FEF, right FEF, or vertex, participants performed a visual discrimination task requiring covert attention to either visual hemifield. Both left and right FEF TMS caused marked attenuation of alpha modulation in the occipitoparietal cortex. Notably, alpha modulation was consistently reduced in the hemisphere contralateral to stimulation, leaving the ipsilateral hemisphere relatively unaffected. Additionally, right FEF TMS enhanced gamma modulation in left visual cortex. Behaviorally, TMS caused a relative slowing of response times to targets contralateral to stimulation during the early task period. Our results suggest that left and right FEF are causally involved in the attentional top-down control of anticipatory alpha power in the contralateral visual system, whereas a right-hemispheric dominance seems to exist for control of stimulus-induced gamma power. These findings contrast the assumption of primarily intrahemispheric connectivity between FEF and parietal cortex, emphasizing the relevance of interhemispheric interactions. The contralaterality of effects may result from a transient functional reorganization of the dorsal attention network after inhibition of either FEF. Copyright © 2015 the authors 0270-6474/15/351638-10$15.00/0.

  5. CAMAC multipurpose microprocessor controller

    International Nuclear Information System (INIS)

    Belyakova, M.P.; Nemesh, T.; Buj Zoan Chong.

    1978-01-01

    The use of CAMAC controllers in an autonomous system of data acquisition and measurement is considered. The system consists of a control intelligence controller, memory modules, and user modules in the CAMAC standard. The controller and all the modules have an output into the highway and this permits to exchange data among them without using special external cables. To increase the servicing rate, an auxiliary controller which has direct access to memory and controls the user modules, is additionally connected to the data acquisition and measurement system. In this case, the intelligence controller is passive. The system of data acquisition can be realized in the form of a multiple system with branch usage. The controller module width is three units, and the controller incorporates the Intel-8080-type microprocessor and the following interfaces: of CAMAC highways, of interruption, of memory bootstrap, and of data sequence channel

  6. Periodic modulations controlling Kuznetsov–Ma soliton formation in nonlinear Schrödinger equations

    Energy Technology Data Exchange (ETDEWEB)

    Tiofack, C.G.L., E-mail: glatchio@yahoo.fr [Univ. Lille, CNRS, UMR 8523 – PhLAM – Physique des Lasers Atomes et Molécules, F-59000 Lille (France); Coulibaly, S.; Taki, M. [Univ. Lille, CNRS, UMR 8523 – PhLAM – Physique des Lasers Atomes et Molécules, F-59000 Lille (France); De Bièvre, S.; Dujardin, G. [Univ. Lille, CNRS, UMR 8524 – Laboratoire Paul Painlevé, F-59000 Lille (France); Équipe-Projet Mephysto, INRIA Lille-Nord Europe (France)

    2017-06-28

    We analyze the exact Kuznetsov–Ma soliton solution of the one-dimensional nonlinear Schrödinger equation in the presence of periodic modulations satisfying an integrability condition. We show that, in contrast to the case without modulation, the Kuznetsov–Ma soliton develops multiple compression points whose number, shape and position are controlled both by the intensity of the modulation and by its frequency. In addition, when this modulation frequency is a rational multiple of the natural frequency of the Kuznetsov–Ma soliton, a scenario similar to a nonlinear resonance is obtained: in this case the spatial oscillations of the Kuznetsov–Ma soliton's intensity are periodic. When the ratio of the two frequencies is irrational, the soliton's intensity is a quasiperiodic function. A striking and important result of our analysis is the possibility to suppress any component of the output spectrum of the Kuznetsov–Ma soliton by a judicious choice of the amplitude and frequency of the modulation. - Highlights: • Exact Kuznetsov–Ma soliton solution in presence of periodic coefficients is obtained. • The multiple compression points of the solution are studied. • The quasi-periodicity of the solution is discussed. • The possibility to suppress any component of the spectrum is analyzed.

  7. First Metatarsal Head and Medial Eminence Widths with and Without Hallux Valgus.

    Science.gov (United States)

    Lenz, Robin C; Nagesh, Darshan; Park, Hannah K; Grady, John

    2016-09-02

    Resection of the medial eminence in hallux valgus surgery is common. True hypertrophy of the medial eminence in hallux valgus is debated. No studies have compared metatarsal head width in patients with hallux valgus and control patients. We reviewed 43 radiographs with hallux valgus and 27 without hallux valgus. We measured medial eminence width, first metatarsal head width, and first metatarsal shaft width in patients with and without radiographic hallux valgus. Medial eminence width was 1.12 mm larger in patients with hallux valgus (P hallux valgus (P hallux valgus. However, frontal plane rotation of the first metatarsal likely accounts for this difference.

  8. Sensorless control method of instant-heating module for a bidet

    Energy Technology Data Exchange (ETDEWEB)

    Jung, D. [Korea Polytechnic Univ. (Korea, Republic of). Dept. of Electronics Engineering

    2006-07-01

    The three types of temperature control schemes for a bidet system are the mechanical type where both hot water and cold water are supplied to bidet system and users control the outlet water; hot water-tank type where temperature in outlet water is slowly controlled in the hot water tanks; and, instant-heating module type where temperature in outlet water is controlled by a ceramic heater and switching device. All types have advantages and disadvantages. This paper addressed the need for a sensor-less control scheme for an instant-heating module for a bidet, which can control water temperature effectively without using the flow-velocity sensor of the flowing water. The sensor-less control scheme is meant to reduce costs and improve reliability. In this study, a steady state model and simplified model of instant-heating module was developed. An estimation algorithm for the value of flow-velocity of water was also proposed. Experimental work performed under various operating conditions was presented to demonstrate the validity of the proposed sensor-less control scheme. The velocity of the flowing water was estimated by monitoring the changes in outlet water temperature and by analyzing the results against information of inlet water temperature and the switching command for Triac bridge circuit. This information can be readily acquired during the cleaning operation of a bidet system. It was concluded that the proposed method can be easily integrated with existing low-cost control schemes. Future work will focus on mass production of the system, such as developing reliable automatic tuning algorithm to apply the proposed scheme for commercial use. 3 refs., 1 tab., 6 figs.

  9. Constant Width Planar Computation Characterizes ACC0

    DEFF Research Database (Denmark)

    Hansen, Kristoffer Arnsfelt

    2006-01-01

    We obtain a characterization of ACC0 in terms of a natural class of constant width circuits, namely in terms of constant width polynomial size planar circuits. This is shown via a characterization of the class of acyclic digraphs which can be embedded on a cylinder surface in such a way that all...

  10. Palindromic widths of nilpotent and wreath products

    Indian Academy of Sciences (India)

    Palindromic width; commutator width; wreath products; nilpotent product. 2000 Mathematics ... An algorithm of the computation of the commutator length in free non-abelian .... It is clear that A(1)B = A × B is the direct sum. Let us list some ...

  11. High Voltage, Fast-Switching Module for Active Control of Magnetic Fields and Edge Plasma Currents

    Science.gov (United States)

    Ziemba, Timothy; Miller, Kenneth; Prager, James; Slobodov, Ilia

    2016-10-01

    Fast, reliable, real-time control of plasma is critical to the success of magnetic fusion science. High voltage and current supplies are needed to mitigate instabilities in all experiments as well as disruption events in large scale tokamaks for steady-state operation. Silicon carbide (SiC) MOSFETs offer many advantages over IGBTs including lower drive energy requirements, lower conduction and switching losses, and higher switching frequency capabilities; however, these devices are limited to 1.2-1.7 kV devices. As fusion enters the long-pulse and burning plasma eras, efficiency of power switching will be important. Eagle Harbor Technologies (EHT), Inc. developing a high voltage SiC MOSFET module that operates at 10 kV. This switch module utilizes EHT gate drive technology, which has demonstrated the ability to increase SiC MOSFET switching efficiency. The module will allow more rapid development of high voltage switching power supplies at lower cost necessary for the next generation of fast plasma feedback and control. EHT is partnering with the High Beta Tokamak group at Columbia to develop detailed high voltage module specifications, to ensure that the final product meets the needs of the fusion science community.

  12. Control units for the system of unified modules for multi-channel analysis (SUMMA)

    International Nuclear Information System (INIS)

    Bushnin, Yu.B.; Denisenko, A.A.; Dunajtsev, A.F.

    1975-01-01

    The control units of the ''SUMMA'' system unified modules for multichannel analysis are described; the system is used in the experimental physics installations of the Institute of High-Energy Physics for operation on-line with an electronic computer (e.c.). The units allow control of several crates of electronic equipment (up to seven) according to a program from the internal program units or from the e.c. to be assured. The organization of the control is similar to the organization of the CAMAC electronic system. Examples of communication between the system and an NR2100 electronic computer are presented

  13. Modulation of magnetic coercivity in Ni thin films by reversible control of strain

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Wen-Chin, E-mail: wclin@ntnu.edu.tw [Department of Physics, National Taiwan Normal University, Taipei 116, Taiwan (China); Huang, Chia-Wei; Ting, Yi-Chieh; Lo, Fang-Yuh [Department of Physics, National Taiwan Normal University, Taipei 116, Taiwan (China); Chern, Ming-Yau [Department of Physics, National Taiwan University, Taipei 106, Taiwan (China)

    2015-05-01

    In this study, we demonstrated the magnetoelectric control of magnetic thin films. (111)-textured Pd/Ni/Pd thin films were prepared on mica/lead zirconium titanate (PZT) substrates for the investigation. The reversible modulation of magnetic coercivity in Ni films was observed through the electric-voltage-controlled strain variation from the PZT substrate. For 14 nm Ni film, the applied electric field of ±350 V/m led to ±0.5% strain variation of PZT, which was transferred to ±0.4% strain variation of Pd/Ni/Pd thin films on mica, and resulted in ∓17 Oe (∓5% of the preliminary magnetic coercivity). The reversible modulation of magnetic coercivity is supposed to be caused by the voltage-controlled strain through the magneto-elastic effect. - Highlights: • The magnetoelectric control of the magnetic coercivity of Pd/Ni/Pd thin films was demonstrated. • The ±0.4% strain variation of 14 nm Ni thin films resulted in ±17 Oe change of H{sub c}. • The reversible modulation of H{sub c} is supposed to be caused by the magneto-elastic effect.

  14. Histogram bin width selection for time-dependent Poisson processes

    International Nuclear Information System (INIS)

    Koyama, Shinsuke; Shinomoto, Shigeru

    2004-01-01

    In constructing a time histogram of the event sequences derived from a nonstationary point process, we wish to determine the bin width such that the mean squared error of the histogram from the underlying rate of occurrence is minimized. We find that the optimal bin widths obtained for a doubly stochastic Poisson process and a sinusoidally regulated Poisson process exhibit different scaling relations with respect to the number of sequences, time scale and amplitude of rate modulation, but both diverge under similar parametric conditions. This implies that under these conditions, no determination of the time-dependent rate can be made. We also apply the kernel method to these point processes, and find that the optimal kernels do not exhibit any critical phenomena, unlike the time histogram method

  15. Histogram bin width selection for time-dependent Poisson processes

    Energy Technology Data Exchange (ETDEWEB)

    Koyama, Shinsuke; Shinomoto, Shigeru [Department of Physics, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502 (Japan)

    2004-07-23

    In constructing a time histogram of the event sequences derived from a nonstationary point process, we wish to determine the bin width such that the mean squared error of the histogram from the underlying rate of occurrence is minimized. We find that the optimal bin widths obtained for a doubly stochastic Poisson process and a sinusoidally regulated Poisson process exhibit different scaling relations with respect to the number of sequences, time scale and amplitude of rate modulation, but both diverge under similar parametric conditions. This implies that under these conditions, no determination of the time-dependent rate can be made. We also apply the kernel method to these point processes, and find that the optimal kernels do not exhibit any critical phenomena, unlike the time histogram method.

  16. Does an attention bias to appetitive and aversive words modulate interference control in youth with ADHD?

    Science.gov (United States)

    Ma, Ili; Mies, Gabry W; Lambregts-Rommelse, Nanda N J; Buitelaar, Jan K; Cillessen, Antonius H N; Scheres, Anouk

    2018-05-01

    Interference control refers to the ability to selectively attend to certain information while ignoring distracting information. This ability can vary as a function of distractor relevance. Distractors that are particularly relevant to an individual may attract more attention than less relevant distractors. This is referred to as attention bias. Weak interference control and altered reward sensitivity are both important features of attention deficit hyperactivity disorder (ADHD). However, interference control is typically studied in isolation. This study integrates both. Youths (aged 9 to 17 years) with ADHD (n = 37, 25 boys) and typically-developing controls (n = 38, 20 boys) completed a Stroop task using appetitive words and matched neutral words to assess whether appetitive distractors diminished interference control more in youths with ADHD than controls. In order to test for specificity, aversive words were also included. As expected, appetitive words disrupted interference control but this effect was not stronger for youths with ADHD than the controls. Aversive words, on the other hand, facilitated interference control. Dimensional analyses revealed that this facilitation effect increased substantially as a function of ADHD symptom severity. Possible mechanisms for this effect include up-regulation of interference control as a function of induced negative mood, or as a function of increased effort. In conclusion, appetitive words do not lead to worse interference control in youths with ADHD compared with controls. Interference control was modulated in a valence-specific manner, concurrent with mood-induced effects on cognitive control.

  17. Pulse Width Affects Scalp Sensation of Transcranial Magnetic Stimulation.

    Science.gov (United States)

    Peterchev, Angel V; Luber, Bruce; Westin, Gregory G; Lisanby, Sarah H

    Scalp sensation and pain comprise the most common side effect of transcranial magnetic stimulation (TMS), which can reduce tolerability and complicate experimental blinding. We explored whether changing the width of single TMS pulses affects the quality and tolerability of the resultant somatic sensation. Using a controllable pulse parameter TMS device with a figure-8 coil, single monophasic magnetic pulses inducing electric field with initial phase width of 30, 60, and 120 µs were delivered in 23 healthy volunteers. Resting motor threshold of the right first dorsal interosseus was determined for each pulse width, as reported previously. Subsequently, pulses were delivered over the left dorsolateral prefrontal cortex at each of the three pulse widths at two amplitudes (100% and 120% of the pulse-width-specific motor threshold), with 20 repetitions per condition delivered in random order. After each pulse, subjects rated 0-to-10 visual analog scales for Discomfort, Sharpness, and Strength of the sensation. Briefer TMS pulses with amplitude normalized to the motor threshold were perceived as slightly more uncomfortable than longer pulses (with an average 0.89 point increase on the Discomfort scale for pulse width of 30 µs compared to 120 µs). The sensation of the briefer pulses was felt to be substantially sharper (2.95 points increase for 30 µs compared to 120 µs pulse width), but not stronger than longer pulses. As expected, higher amplitude pulses increased the perceived discomfort and strength, and, to a lesser degree the perceived sharpness. Our findings contradict a previously published hypothesis that briefer TMS pulses are more tolerable. We discovered that the opposite is true, which merits further study as a means of enhancing tolerability in the context of repetitive TMS. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Performance Evaluation of a High Bandwidth Liquid Fuel Modulation Valve for Active Combustion Control

    Science.gov (United States)

    Saus, Joseph R.; DeLaat, John C.; Chang, Clarence T.; Vrnak, Daniel R.

    2012-01-01

    At the NASA Glenn Research Center, a characterization rig was designed and constructed for the purpose of evaluating high bandwidth liquid fuel modulation devices to determine their suitability for active combustion control research. Incorporated into the rig s design are features that approximate conditions similar to those that would be encountered by a candidate device if it were installed on an actual combustion research rig. The characterized dynamic performance measures obtained through testing in the rig are planned to be accurate indicators of expected performance in an actual combustion testing environment. To evaluate how well the characterization rig predicts fuel modulator dynamic performance, characterization rig data was compared with performance data for a fuel modulator candidate when the candidate was in operation during combustion testing. Specifically, the nominal and off-nominal performance data for a magnetostrictive-actuated proportional fuel modulation valve is described. Valve performance data were collected with the characterization rig configured to emulate two different combustion rig fuel feed systems. Fuel mass flows and pressures, fuel feed line lengths, and fuel injector orifice size was approximated in the characterization rig. Valve performance data were also collected with the valve modulating the fuel into the two combustor rigs. Comparison of the predicted and actual valve performance data show that when the valve is operated near its design condition the characterization rig can appropriately predict the installed performance of the valve. Improvements to the characterization rig and accompanying modeling activities are underway to more accurately predict performance, especially for the devices under development to modulate fuel into the much smaller fuel injectors anticipated in future lean-burning low-emissions aircraft engine combustors.

  19. Development and implementation of quality control strategies for CMS silicon strip tracker modules

    International Nuclear Information System (INIS)

    Dirkes, G.

    2003-01-01

    The CMS group in Karlsruhe is involved in the construction of the silicon trackers end-caps and will produce and qualify the 1 600 modules of ring 5. Therefore automatic test systems for module qualification are developed and test strategies are worked out. For the electrical tests a complete readout system is developed, based on readout modules available within the collaboration and extended by home build modules. These are based on a modular approach with less complex functional units attached to a motherboard and includes key functionalities like clock and trigger generation and their distribution, high and low voltage supply and test signal generation usable with lasers or infrared LEDs. The motherboard is connected to a standard PC, hosting a fast ADC, interface cards to the motherboard and the front-end electronics. Already during the R and D phase of this readout system, first prototype tests were performed and some weak points of the design were uncovered, resulting in changes of the electronics design of the front end hybrids. Two test stations are built. The first one focuses on a fast functionality test, which includes an active thermal cycle with readout at -10 C performed for each individual module. The other test station focuses on debugging and repair requirements. It disposes of sufficient space for a flexible use of the system, including the possibility of additional test options with lasers, radioactive sources, probes and LEDs. For quality control measurements at module level it turned out, that LEDs are of good use: Besides external signal generation by running them in a pulsed way, they can be used for constant illumination of sensors, inducing an artificial leakage current. This led to the discovery of gain losses of complete readout chips induced by shorted AC coupling capacitances of several readout channels, which are called pinholes. Therefore pinholes must be unbonded from the front end preamplifier, which requires faultless

  20. Quantum well saturable absorber mirror with electrical control of modulation depth

    DEFF Research Database (Denmark)

    Liu, Xiaomin; Rafailov, Edik U.; Livshits, Daniil

    2010-01-01

    in the range 2.5–0.5%, as measured by nonlinear reflectivity of 450 fs long laser pulses with 1065 nm central wavelength, in the pump fluence range 1.6–26.7 J /cm2. This electrical control of the modulation depth is achieved by controlling the small-signal loss of the SESAM via quantum-confined Stark effect......We demonstrate a quantum well QW semiconductor saturable absorber mirror SESAM comprising low-temperature grown InGaAs/GaAs QWs incorporated into a p-i-n structure. By applying the reverse bias voltage in the range 0–2 V to the p-i-n structure, we were able to change the SESAM modulation depth...

  1. Predictive Trailing-Edge Modulation Average Current Control in DC-DC Converters

    Directory of Open Access Journals (Sweden)

    LASCU, D.

    2013-11-01

    Full Text Available The paper investigates predictive digital average current control (PDACC in dc/dc converters using trailing-edge modulation (TEM. The study is focused on the recurrence duty cycle equation and then stability analysis is performed. It is demonstrated that average current control using trailing-edge modulation is stable on the whole range of the duty cycle and thus design problems are highly reduced. The analysis is carried out in a general manner, independent of converter topology and therefore the results can then be easily applied for a certain converter (buck, boost, buck-boost, etc.. The theoretical considerations are confirmed for a boost converter first using the MATLAB program based on state-space equations and finally with the CASPOC circuit simulation package.

  2. Engineering aspects of a thermal control subsystem for the 25 kW power module

    Science.gov (United States)

    Schroeder, P. E.

    1979-01-01

    The paper presents the key trade study results, analysis results, and the recommended thermal control approach for the 25 kW power module defined by NASA. Power conversion inefficiencies and component heat dissipation results in a minimum heat rejection requirement of 9 kW to maintain the power module equipment at desired temperature levels. Additionally, some cooling capacity should be provided for user payloads in the sortie and free-flying modes. The baseline thermal control subsystem includes a dual-loop-pumped Freon-21 coolant with the heat rejected from deployable existing orbiter radiators. Thermal analysis included an assessment of spacecraft orientations, radiator shapes and locations, and comparison of hybrid heat pipe and all liquid panels.

  3. Joint space width in dysplasia of the hip

    DEFF Research Database (Denmark)

    Jacobsen, Steffen; Sonne-Holm, Stig; Søballe, K

    2005-01-01

    . Neither subjects with dysplasia nor controls had radiological signs of ongoing degenerative disease at admission. The primary radiological discriminator of degeneration of the hip was a change in the minimum joint space width over time. There were no significant differences between these with dysplasia...

  4. Control scheme for power modulation of a free piston Stirling engine

    Science.gov (United States)

    Dhar, Manmohan

    1989-01-01

    The present invention relates to a control scheme for power modulation of a free-piston Stirling engine-linear alternator power generator system. The present invention includes connecting an autotransformer in series with a tuning capacitance between a linear alternator and a utility grid to maintain a constant displacement to piston stroke ratio and their relative phase angle over a wide range of operating conditions.

  5. Lunar Module ECS (Environmental Control System) - Design Considerations and Failure Modes. Part 1

    Science.gov (United States)

    Interbartolo, Michael

    2009-01-01

    Design considerations and failure modes for the Lunar Module (LM) Environmental Control System (ECS) are described. An overview of the the oxygen supply and cabin pressurization, atmosphere revitalization, water management and heat transport systems are provided. Design considerations including reliability, flight instrumentation, modularization and the change to the use of batteries instead of fuel cells are discussed. A summary is provided for the LM ECS general testing regime.

  6. Risk-based Reliability Assessment of Subsea Control module for Offshore Oil and Gas production

    OpenAIRE

    Umofia, Anietie Nnana

    2014-01-01

    Offshore oil and gas exploitation is principally conducted using dry or wet tree systems, otherwise called the subsea Xmas tree system. Due to the shift to deeper waters, subsea production system (SPS) has come to be a preferred technology with attendant economic benefits. At the centre of the SPS is the subsea control module (SCM), responsible for the proper functioning and monitoring of the entire system. With increasing search for hydrocarbons in deep and ultra-deepwaters...

  7. Performance analysis of joint diversity combining, adaptive modulation, and power control schemes

    KAUST Repository

    Qaraqe, Khalid A.

    2011-01-01

    Adaptive modulation and diversity combining represent very important adaptive solutions for future generations of wireless communication systems. Indeed, in order to improve the performance and the efficiency of these systems, these two techniques have been recently used jointly in new schemes named joint adaptive modulation and diversity combining (JAMDC) schemes. Considering the problem of finding low hardware complexity, bandwidth-efficient, and processing-power efficient transmission schemes for a downlink scenario and capitalizing on some of these recently proposed JAMDC schemes, we propose and analyze in this paper three joint adaptive modulation, diversity combining, and power control (JAMDCPC) schemes where a constant-power variable-rate adaptive modulation technique is used with an adaptive diversity combining scheme and a common power control process. More specifically, the modulation constellation size, the number of combined diversity paths, and the needed power level are jointly determined to achieve the highest spectral efficiency with the lowest possible processing power consumption quantified in terms of the average number of combined paths, given the fading channel conditions and the required bit error rate (BER) performance. In this paper, the performance of these three JAMDCPC schemes is analyzed in terms of their spectral efficiency, processing power consumption, and error-rate performance. Selected numerical examples show that these schemes considerably increase the spectral efficiency of the existing JAMDC schemes with a slight increase in the average number of combined paths for the low signal-to-noise ratio range while maintaining compliance with the BER performance and a low radiated power which yields to a substantial decrease in interference to co-existing users and systems. © 2011 IEEE.

  8. Fast and Robust Nanocellulose Width Estimation Using Turbidimetry.

    Science.gov (United States)

    Shimizu, Michiko; Saito, Tsuguyuki; Nishiyama, Yoshiharu; Iwamoto, Shinichiro; Yano, Hiroyuki; Isogai, Akira; Endo, Takashi

    2016-10-01

    The dimensions of nanocelluloses are important factors in controlling their material properties. The present study reports a fast and robust method for estimating the widths of individual nanocellulose particles based on the turbidities of their water dispersions. Seven types of nanocellulose, including short and rigid cellulose nanocrystals and long and flexible cellulose nanofibers, are prepared via different processes. Their widths are calculated from the respective turbidity plots of their water dispersions, based on the theory of light scattering by thin and long particles. The turbidity-derived widths of the seven nanocelluloses range from 2 to 10 nm, and show good correlations with the thicknesses of nanocellulose particles spread on flat mica surfaces determined using atomic force microscopy. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Joint space width in dysplasia of the hip

    DEFF Research Database (Denmark)

    Jacobsen, Steffen; Sonne-Holm, Stig; Søballe, K

    2005-01-01

    In a longitudinal case-control study, we followed 81 subjects with dysplasia of the hip and 136 control subjects without dysplasia for ten years assessing radiological evidence of degeneration of the hip at admission and follow-up. There were no cases of subluxation in the group with dysplasia....... Neither subjects with dysplasia nor controls had radiological signs of ongoing degenerative disease at admission. The primary radiological discriminator of degeneration of the hip was a change in the minimum joint space width over time. There were no significant differences between these with dysplasia...... and controls in regard to age, body mass index or occupational exposure to daily repeated lifting at admission.We found no significant differences in the reduction of the joint space width at follow-up between subjects with dysplasia and the control subjects nor in self-reported pain in the hip...

  10. Magnetoelectric control of valley and spin in a silicene nanoribbon modulated by the magnetic superlattices

    Energy Technology Data Exchange (ETDEWEB)

    An, Xing-Tao, E-mail: anxt@hku.hk

    2015-03-20

    The control of valley and spin degrees of freedom and the transport properties of electrons in a zigzag silicene nanoribbon modulated by the magnetic superlattices are investigated theoretically. Due to the valley–spin locking effect in silicene, the valley degree of freedom can be controlled by magnetic means. The valley or/and spin selection induced by the exchange field result in the perfect spin–valley filter and tunneling magnetoresistance effect in the double ferromagnetic barriers on the surface of the silicene nanoribbon. It is more interesting that there are valley-resolved minigaps and minibands in the zigzag silicene nanoribbon modulated by the magnetic superlattices which give rise to the periodically modulated spin (or/and valley) polarization and tunneling magnetoresistance. The results obtained may have certain practical significance in applications for future valleytronic and spintronic devices. - Highlights: • The valley can be controlled by a magnetic field in silicene. • The valley-resolved miniband transport is studied in the silicene superlattices. • There are the perfect spin–valley filter and tunneling magnetoresistance effect.

  11. The effects of lane width, shoulder width, and road cross-sectional reallocation on drivers' behavioral adaptations.

    Science.gov (United States)

    Mecheri, Sami; Rosey, Florence; Lobjois, Régis

    2017-07-01

    Previous research has shown that lane-width reduction makes drivers operate vehicles closer to the center of the road whereas hard-shoulder widening induces a position farther away from the road's center. The goal of the present driving-simulator study was twofold. First, it was aimed at further investigating the respective effects of lane and shoulder width on in-lane positioning strategies, by examining vehicle distance from the center of the lane. The second aim was to assess the impact on safety of three possible cross-sectional reallocations of the width of the road (i.e., three lane-width reductions with concomitant shoulder widening at a fixed cross-sectional width) as compared to a control road. The results confirmed that lane-width reduction made participants drive closer to the road's center. However, in-lane position was affected differently by lane narrowing, depending on the traffic situation. In the absence of oncoming traffic, lane narrowing gave rise to significant shifts in the car's distance from the lane's center toward the edge line, whereas this distance remained similar across lane widths during traffic periods. When the shoulders were at least 0.50m wide, participants drove farther away from both the road center and the lane center. Road reallocation operations resulted in vehicles positioned farther away from the edge of the road and less swerving behavior, without generating higher driving speeds. Finally, it is argued that road-space reallocation may serve as a good low-cost tool for providing a recovery area for steering errors, without impairing drivers' behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Real-Time Performance of Mechatronic PZT Module Using Active Vibration Feedback Control.

    Science.gov (United States)

    Aggogeri, Francesco; Borboni, Alberto; Merlo, Angelo; Pellegrini, Nicola; Ricatto, Raffaele

    2016-09-25

    This paper proposes an innovative mechatronic piezo-actuated module to control vibrations in modern machine tools. Vibrations represent one of the main issues that seriously compromise the quality of the workpiece. The active vibration control (AVC) device is composed of a host part integrated with sensors and actuators synchronized by a regulator; it is able to make a self-assessment and adjust to alterations in the environment. In particular, an innovative smart actuator has been designed and developed to satisfy machining requirements during active vibration control. This study presents the mechatronic model based on the kinematic and dynamic analysis of the AVC device. To ensure a real time performance, a H2-LQG controller has been developed and validated by simulations involving a machine tool, PZT actuator and controller models. The Hardware in the Loop (HIL) architecture is adopted to control and attenuate the vibrations. A set of experimental tests has been performed to validate the AVC module on a commercial machine tool. The feasibility of the real time vibration damping is demonstrated and the simulation accuracy is evaluated.

  13. Fully interferometric controllable anomalous refraction efficiency using cross modulation with plasmonic metasurfaces.

    Science.gov (United States)

    Liu, Zhaocheng; Chen, Shuqi; Li, Jianxiong; Cheng, Hua; Li, Zhancheng; Liu, Wenwei; Yu, Ping; Xia, Ji; Tian, Jianguo

    2014-12-01

    We present a method of fully interferometric, controllable anomalous refraction efficiency by introducing cross-modulated incident light based on plasmonic metasurfaces. Theoretical analyses and numerical simulations indicate that the anomalous and ordinary refracted beams generated from two opposite-helicity incident beams and following the generalized Snell's law will have a superposition for certain incident angles, and the anomalous refraction efficiency can be dynamically controlled by changing the relative phase of the incident sources. As the incident wavelength nears the resonant wavelength of the plasmonic metasurfaces, two equal-amplitude incident beams with opposite helicity can be used to control the anomalous refraction efficiency. Otherwise, two unequal-amplitude incident beams with opposite helicity can be used to fully control the anomalous refraction efficiency. This Letter may offer a further step in the development of controllable anomalous refraction.

  14. Analogical study of the servo-control of a reactivity modulator

    International Nuclear Information System (INIS)

    Le Bot, Michel

    1969-03-01

    In the context of the study of the transfer functions related to the Cabri reactor, this paper presents: the objective of the servo-control (reactivity modulator, reasons for the analogical study), the principles of the servo-control (description of the servo-controlled system, elaboration of the error signal, principles of the phase meter, critical analysis of different types of phase meters), the analogical formulation (transfer diagram of the process, analogical simulation of the process, analogical realization of the phase meter, simulation of the Low Frequency generator), study of the controlled system and results (system responses to echelon and ramp signals, responses of the controlled system with the phase meter in feedback)

  15. Grid Voltage Modulated Control of Grid-Connected Voltage Source Inverters under Unbalanced Grid Conditions

    DEFF Research Database (Denmark)

    Li, Mingshen; Gui, Yonghao; Quintero, Juan Carlos Vasquez

    2017-01-01

    In this paper, an improved grid voltage modulated control (GVM) with power compensation is proposed for grid-connected voltage inverters when the grid voltage is unbalanced. The objective of the proposed control is to remove the power ripple and to improve current quality. Three power compensation...... objectives are selected to eliminate the negative sequence components of currents. The modified GVM method is designed to obtain two separate second-order systems for not only the fast convergence rate of the instantaneous active and reactive powers but also the robust performance. In addition, this method...

  16. Testosterone Modulates Altered Prefrontal Control of Emotional Actions in Psychopathic Offenders(1,2,3).

    Science.gov (United States)

    Volman, Inge; von Borries, Anna Katinka Louise; Bulten, Berend Hendrik; Verkes, Robbert Jan; Toni, Ivan; Roelofs, Karin

    2016-01-01

    Psychopathic individuals are notorious for their controlled goal-directed aggressive behavior. Yet, during social challenges, they often show uncontrolled emotional behavior. Healthy individuals can control their social emotional behavior through anterior prefrontal cortex (aPFC) downregulation of neural activity in the amygdala, with testosterone modulating aPFC-amygdala coupling. This study tests whether individual differences in this neuroendocrine system relate to the paradoxical lack of emotional control observed in human psychopathic offenders. Emotional control was operationalized with an fMRI-adapted approach-avoidance task requiring rule-driven control over rapid emotional responses. Fifteen psychopathic offenders and 19 matched healthy control subjects made approaching and avoiding movements in response to emotional faces. Control of social emotional behavior was required during affect-incongruent trials, when participants had to override affect-congruent, automatic action tendencies and select the opposite response. Psychopathic offenders showed less control-related aPFC activity and aPFC-amygdala coupling during trials requiring control of emotional actions, when compared with healthy control subjects. This pattern was particularly pronounced in psychopathic individuals with high endogenous testosterone levels. These findings suggest that reduced prefrontal coordination underlies reduced behavioral control in psychopathic offenders during emotionally provoking situations. Even though the modest sample size warrants replication, the modulatory role of endogenous testosterone on the aPFC-amygdala circuit suggests a neurobiological substrate of individual differences that is relevant for the advancement of treatment and the reduction of recidivism.

  17. Beam manipulating by metallic nano-slits with variant widths.

    Science.gov (United States)

    Shi, Haofei; Wang, Changtao; Du, Chunlei; Luo, Xiangang; Dong, Xiaochun; Gao, Hongtao

    2005-09-05

    A novel method is proposed to manipulate beam by modulating light phase through a metallic film with arrayed nano-slits, which have constant depth but variant widths. The slits transport electro-magnetic energy in the form of surface plasmon polaritons (SPPs) in nanometric waveguides and provide desired phase retardations of beam manipulating with variant phase propagation constant. Numerical simulation of an illustrative lens design example is performed through finite-difference time-domain (FDTD) method and shows agreement with theory analysis result. In addition, extraordinary optical transmission of SPPs through sub-wavelength metallic slits is observed in the simulation and helps to improve elements' energy using factor.

  18. In-situ calibration: migrating control system IP module calibration from the bench to the storage ring

    International Nuclear Information System (INIS)

    Weber, Jonah M.; Chin, Michael

    2002-01-01

    The Control System for the Advanced Light Source (ALS) at Lawrence Berkeley National Lab (LBNL) uses in-house designed IndustryPack(registered trademark) (IP) modules contained in compact PCI (cPCI) crates with 16-bit analog I/O to control instrumentation. To make the IP modules interchangeable, each module is calibrated for gain and offset compensation. We initially developed a method of verifying and calibrating the IP modules in a lab bench test environment using a PC with LabVIEW. The subsequent discovery that the ADCs have significant drift characteristics over periods of days of installed operation prompted development of an ''in-situ'' calibration process--one in which the IP modules can be calibrated without removing them from the cPCI crates in the storage ring. This paper discusses the original LabVIEW PC calibration and the migration to the proposed in-situ EPICS control system calibration

  19. Decreased Modulation of EEG Oscillations in High-Functioning Autism During a Motor Control Task

    Directory of Open Access Journals (Sweden)

    Joshua Benjamin Ewen

    2016-05-01

    Full Text Available Autism spectrum disorders (ASD are thought to result in part from altered cortical excitatory-inhibitory balance; this pathophysiology may impact the generation of oscillations on EEG. We investigated premotor-parietal cortical physiology associated with praxis, which has strong theoretical and empirical associations with ASD symptomatology. 25 children with high-functioning ASD (HFA and 33 controls performed a praxis task involving the pantomiming of tool use, while EEG was recorded. We assessed task-related modulation of signal power in alpha and beta frequency bands. Compared with controls, subjects with HFA showed 27% less left central (motor/premotor beta (18-22 Hz event-related desynchronization (ERD (p = 0.030, as well as 24% less left parietal alpha (7-13 Hz ERD (p = 0.046. Within the HFA group, blunting of central ERD attenuation was associated with impairments in clinical measures of praxis imitation (r = -0.4; p = 0.04 and increased autism severity (r = 0.48; p = 0.016. The modulation of central beta activity is associated, among other things, with motor imagery, which may be necessary for imitation. Impaired imitation has been associated with core features of ASD. Altered modulation of oscillatory activity may be mechanistically involved in those aspects of motor network function that relate to the core symptoms of ASD.

  20. Results of the quality control treatments plans in volume arc therapy modulated for thirty treated patients

    International Nuclear Information System (INIS)

    Fenoglietto, P.; Ailleres, N.; Simeon, S.; Santoro, L.; Dubois, J.B.; Azria, D.

    2009-01-01

    The intensity modulated radiotherapy (I.M.R.T.) provided by voluminal arc therapy was implemented at the Val d'Aurelle regional center against cancer in november 2008. In May 2009 more than 30 patients have benefited from this technique in our institution and for each of them, the dosimetry planing has been checked under the accelerator before the treatment. The analysis of these results of measures under accelerators equipped of 120 leave collimators and for optimizations realised with the Rapid-arc computer code from Varian. The issue of a treatment in intensity modulation by voluminal arc therapy gives satisfying results falling within the range of those previously found in conventional I.M.R.T.. Besides, the quality control is faster because of lesser number of beams to verify. (N.C.)

  1. Global Model of Time-Modulated Electronegative Discharges for Neutral Radical and Electron Temperature Control

    Science.gov (United States)

    Kim, Sungjin; Lieberman, M. A.; Lichtenberg, A. J.

    2003-10-01

    Control and reduction of neutral radical flux/ion flux ratio and electron temperature Te is required for next generation etching in the microelectronics industry. We investigate time-modulated power for these purposes using a volume-averaged (global) oxygen discharge model, We consider pressures of 10-50 mTorr and plasma densities of 10^10-10^11 cm-3. In this regime, the discharge is found to be weakly electronegative. The modulation period and the duty ratio (on-time/period) are varied to determine the optimum conditions for reduction of FR= O-atom flux/ion flux and T_e. Two chambers with different height/diameter ratios (SMART Contract SM99-10051.

  2. Modulated Magnetic Nanowires for Controlling Domain Wall Motion: Toward 3D Magnetic Memories

    KAUST Repository

    Ivanov, Yurii P.; Chuvilin, Andrey; Lopatin, Sergei; Kosel, Jü rgen

    2016-01-01

    Cylindrical magnetic nanowires are attractive materials for next generation data storage devices owing to the theoretically achievable high domain wall velocity and their efficient fabrication in highly dense arrays. In order to obtain control over domain wall motion, reliable and well-defined pinning sites are required. Here, we show that modulated nanowires consisting of alternating nickel and cobalt sections facilitate efficient domain wall pinning at the interfaces of those sections. By combining electron holography with micromagnetic simulations, the pinning effect can be explained by the interaction of the stray fields generated at the interface and the domain wall. Utilizing a modified differential phase contrast imaging, we visualized the pinned domain wall with a high resolution, revealing its three-dimensional vortex structure with the previously predicted Bloch point at its center. These findings suggest the potential of modulated nanowires for the development of high-density, three-dimensional data storage devices. © 2016 American Chemical Society.

  3. A Flexible VHDL Floating Point Module for Control Algorithm Implementation in Space Applications

    Science.gov (United States)

    Padierna, A.; Nicoleau, C.; Sanchez, J.; Hidalgo, I.; Elvira, S.

    2012-08-01

    The implementation of control loops for space applications is an area with great potential. However, the characteristics of this kind of systems, such as its wide dynamic range of numeric values, make inadequate the use of fixed-point algorithms.However, because the generic chips available for the treatment of floating point data are, in general, not qualified to operate in space environments and the possibility of using an IP module in a FPGA/ASIC qualified for space is not viable due to the low amount of logic cells available for these type of devices, it is necessary to find a viable alternative.For these reasons, in this paper a VHDL Floating Point Module is presented. This proposal allows the design and execution of floating point algorithms with acceptable occupancy to be implemented in FPGAs/ASICs qualified for space environments.

  4. Implementation of the Orbital Maneuvering Systems Engine and Thrust Vector Control for the European Service Module

    Science.gov (United States)

    Millard, Jon

    2014-01-01

    The European Space Agency (ESA) has entered into a partnership with the National Aeronautics and Space Administration (NASA) to develop and provide the Service Module (SM) for the Orion Multipurpose Crew Vehicle (MPCV) Program. The European Service Module (ESM) will provide main engine thrust by utilizing the Space Shuttle Program Orbital Maneuvering System Engine (OMS-E). Thrust Vector Control (TVC) of the OMS-E will be provided by the Orbital Maneuvering System (OMS) TVC, also used during the Space Shuttle Program. NASA will be providing the OMS-E and OMS TVC to ESA as Government Furnished Equipment (GFE) to integrate into the ESM. This presentation will describe the OMS-E and OMS TVC and discuss the implementation of the hardware for the ESM.

  5. Modulated Magnetic Nanowires for Controlling Domain Wall Motion: Toward 3D Magnetic Memories

    KAUST Repository

    Ivanov, Yurii P.

    2016-05-03

    Cylindrical magnetic nanowires are attractive materials for next generation data storage devices owing to the theoretically achievable high domain wall velocity and their efficient fabrication in highly dense arrays. In order to obtain control over domain wall motion, reliable and well-defined pinning sites are required. Here, we show that modulated nanowires consisting of alternating nickel and cobalt sections facilitate efficient domain wall pinning at the interfaces of those sections. By combining electron holography with micromagnetic simulations, the pinning effect can be explained by the interaction of the stray fields generated at the interface and the domain wall. Utilizing a modified differential phase contrast imaging, we visualized the pinned domain wall with a high resolution, revealing its three-dimensional vortex structure with the previously predicted Bloch point at its center. These findings suggest the potential of modulated nanowires for the development of high-density, three-dimensional data storage devices. © 2016 American Chemical Society.

  6. Application handbook for a Standardized Control Module (SCM) for DC-DC converters, volume 1

    Science.gov (United States)

    Lee, F. C.; Mahmoud, M. F.; Yu, Y.

    1980-01-01

    The standardized control module (SCM) was developed for application in the buck, boost and buck/boost DC-DC converters. The SCM used multiple feedback loops to provide improved input line and output load regulation, stable feedback control system, good dynamic transient response and adaptive compensation of the control loop for changes in open loop gain and output filter time constraints. The necessary modeling and analysis tools to aid the design engineer in the application of the SCM to DC-DC Converters were developed. The SCM functional block diagram and the different analysis techniques were examined. The average time domain analysis technique was chosen as the basic analytical tool. The power stage transfer functions were developed for the buck, boost and buck/boost converters. The analog signal and digital signal processor transfer functions were developed for the three DC-DC Converter types using the constant on time, constant off time and constant frequency control laws.

  7. Application handbook for a Standardized Control Module (SCM) for DC-DC converters, volume 1

    Science.gov (United States)

    Lee, F. C.; Mahmoud, M. F.; Yu, Y.

    1980-04-01

    The standardized control module (SCM) was developed for application in the buck, boost and buck/boost DC-DC converters. The SCM used multiple feedback loops to provide improved input line and output load regulation, stable feedback control system, good dynamic transient response and adaptive compensation of the control loop for changes in open loop gain and output filter time constraints. The necessary modeling and analysis tools to aid the design engineer in the application of the SCM to DC-DC Converters were developed. The SCM functional block diagram and the different analysis techniques were examined. The average time domain analysis technique was chosen as the basic analytical tool. The power stage transfer functions were developed for the buck, boost and buck/boost converters. The analog signal and digital signal processor transfer functions were developed for the three DC-DC Converter types using the constant on time, constant off time and constant frequency control laws.

  8. Analysis on Longitudinal Dose according to Change of Field Width

    International Nuclear Information System (INIS)

    Jung, Won Seok; Shin, Ryung Mi; Oh, Byung Cheon; Jo, Jun Young; Kim, Gi Chul; Choi, Tae Gu; Back, Jong Geal

    2011-01-01

    To analyze the accuracy of tumor volume dose following field width change, to check the difference of dose change by using self-made moving car, and to evaluate practical delivery tumor dose when tomotherapy in the treatment of organ influenced by breathing. By using self-made moving car, the difference of longitudinal movement (0.0 cm, 1.0 cm, 1.5 cm, 2.0 cm) was applied and compared calculated dose with measured dose according to change of field width (1.05 cm, 2.50 cm, 5.02 cm) and apprehended margin of error. Then done comparative analysis in degree of photosensitivity of DQA film measured by using Gafchromic EBT film. Dose profile and Gamma histogram were used to measure degree of photosensitivity of DQA film. When field width were 1.05 cm, 2.50 cm, 5.02 cm, margin of error of dose delivery coefficient was -2.00%, -0.39%, -2.55%. In dose profile of Gafchromic EBT film's analysis, the movement of moving car had greater motion toward longitudinal direction and as field width was narrower, big error increased considerably at high dose part compared to calculated dose. The more field width was narrowed, gamma index had a large considerable influence of moving at gamma histogram. We could check the difference of longitudinal dose of moving organ. In order to small field width and minimize organ moving due to breathing, it is thought to be needed to develop breathing control unit and fixation tool.

  9. Investigation of Pitch and Jaw Width to Decrease Delivery Time of Helical Tomotherapy Treatments for Head and Neck Cancer

    International Nuclear Information System (INIS)

    Moldovan, Monica; Fontenot, Jonas D.; Gibbons, John P.; Lee, Tae Kyu; Rosen, Isaac I.; Fields, Robert S.; Hogstrom, Kenneth R.

    2011-01-01

    Helical tomotherapy plans using a combination of pitch and jaw width settings were developed for 3 patients previously treated for head and neck cancer. Three jaw widths (5, 2.5, and 1 cm) and 4 pitches (0.86, 0.43, 0.287, and 0.215) were used with a (maximum) modulation factor setting of 4. Twelve plans were generated for each patient using an identical optimization procedure (e.g., number of iterations, objective weights, and penalties, etc.), based on recommendations from TomoTherapy (Madison, WI). The plans were compared using isodose plots, dose volume histograms, dose homogeneity indexes, conformity indexes, radiobiological models, and treatment times. Smaller pitches and jaw widths showed better target dose homogeneity and sparing of normal tissue, as expected. However, the treatment time increased inversely proportional to the jaw width, resulting in delivery times of 24 ± 1.9 min for the 1-cm jaw width. Although treatment plans produced with the 2.5-cm jaw were dosimetrically superior to plans produced with the 5-cm jaw, subsequent calculations of tumor control probabilities and normal tissue complication probabilities suggest that these differences may not be radiobiologically meaningful. Because treatment plans produced with the 5-cm jaw can be delivered in approximately half the time of plans produced with the 2.5-cm jaw (5.1 ± 0.6 min vs. 9.5 ± 1.1 min), use of the 5-cm jaw in routine treatment planning may be a viable approach to decreasing treatment delivery times from helical tomotherapy units.

  10. The data module, the missing link in high level control languages

    International Nuclear Information System (INIS)

    Crowley-Milling, M.C.

    1979-01-01

    In order to be able to use the full power and simplicity of a high level language for writing plant control programs, it must be possible to use the plant variables in the same manner as program variables, completely transparent to the address structure of the hardware and interface. Some of the high level languages provide facilities for writing procedures or subroutines to make this possible. However, most of the facilities provided share a number of disadvantages: they are usually relatively complicated for the user, involving passing many parameters which the programmer has to specify at each call; they usually have restrictions on the data types that can be used, and the data bases are normally organised to suit the interface system. However, the high level programmer is interested in the equipment to be controlled such as motors, pumps, power supplies, valves, etc., rather than the means of interfacing the equipment, and it greatly simplifies his task if he can call for actions on these items, using simple mnemonic names and a simple format. The design of the control system for the CERN 400 GeV proton accelerator, using a network of some thirty computers, provided the opportunity to try out a different approach, using an interpreter for the high-level control language NODAL, together with special functions which are called 'data modules'. The use of the data module and interpreter are described. (author)

  11. Reward-driven modulation of adaptive control: How prospective monetary gains interact with unpredictable control demands

    NARCIS (Netherlands)

    Marien, Hans; Aarts, Henk; Custers, Ruud

    2014-01-01

    Shifting attention is an effortful control process and incurs a cost on the cognitive system. Previous research suggests that rewards, such as monetary gains, will selectively enhance the ability to shift attention when this demand for control is explicitly cued. Here, we hypothesized that

  12. Implementation of CTRLPOS, a VENTURE module for control rod position criticality searches, control rod worth curve calculations, and general criticality searches

    Energy Technology Data Exchange (ETDEWEB)

    Smith, L.A.; Renier, J.P.

    1994-06-01

    A module in the VENTURE reactor analysis code system, CTRLPOS, is developed to position control rods and perform control rod position criticality searches. The module is variably dimensioned so that calculations can be performed with any number of control rod banks each having any number of control rods. CTRLPOS can also calculate control rod worth curves for a single control rod or a bank of control rods. Control rod depletion can be calculated to provide radiation source terms. These radiation source terms can be used to predict radiation doses to personnel and estimate the shielding and long-term storage requirements for spent control rods. All of these operations are completely automated. The numerous features of the module are discussed in detail. The necessary input data for the CTRLPOS module is explained. Several sample problems are presented to show the flexibility of the module. The results presented with the sample problems show that the CTRLPOS module is a powerful tool which allows a wide variety of calculations to be easily performed.

  13. Morphodynamics structures induced by variations of the channel width

    Science.gov (United States)

    Duro, Gonzalo; Crosato, Alessandra; Tassi, Pablo

    2014-05-01

    In alluvial channels, forcing effects, such as a longitudinally varying width, can induce the formation of steady bars (Olesen, 1984). The type of bars that form, such as alternate, central or multiple, will mainly depend on the local flow width-to-depth ratio and on upstream conditions (Struiksma et al., 1985). The effects on bar formation of varying the channel width received attention only recently and investigations, based on flume experiments and mathematical modelling, are mostly restricted to small longitudinal sinusoidal variations of the channel width (e.g. Repetto et al., 2002; Wu and Yeh, 2005, Zolezzi et al., 2012; Frascati and Lanzoni, 2013). In this work, we analyze the variations in equilibrium bed topography in a longitudinal width-varying channel with characteristic scales of the Waal River (The Netherlands) using two different 2D depth-averaged morphodynamic models, one based on the Delft3D code and one on Telemac-Mascaret system. In particular, we explore the effects of changing the wavelength of sinusoidal width variations in a straight channel, focusing on the effects of the spatial lag between bar formation and forcing that is observed in numerical models and laboratory experiments (e.g. Crosato et al, 2011). We extend the investigations to finite width variations in which longitudinal changes of the width-to-depth ratio are such that they may affect the type of bars that become unstable (alternate, central or multiple bars). Numerical results are qualitatively validated with field observations and the resulting morphodynamic pattern is compared with the physics-based predictor of river bar modes by Crosato and Mosselman (2009). The numerical models are finally used to analyse the experimental conditions of Wu and Yeh (2005). The study should be seen as merely exploratory. The aim is to investigate possible approaches for future research aiming at assessing the effects of artificial river widening and narrowing to control bar formation in

  14. A ballistics module as a part of the fire control system

    Directory of Open Access Journals (Sweden)

    Branka R. Luković

    2013-10-01

    Full Text Available This article presents a ballistics module as a part of the fire control system of weapons for fire support (mortars, artillery weapons and rocket launchers. The software is "open" with the prominence of autonomy work. It can be modulated and adapted on the user demand. Moreover, it is independent of the hardware base. Introduction: The fire control system is based on a ballistic module (BM which determines the firing data for each weapon tool in the battery. Ballistic calculations, for the given position of the target in relation to the position of tools in the given weather conditions, determine firing data (elevation, direction, timing and locating devices so that the missile seems to cause the desired effect. This paper gives the basic information about the features the BM performs and the manner of their implementation in the fire control system without going into algorithmic solution procedures. Ballistic problem in the fire control system: Ballistic calculation is based on a trajectory calculation of all kinds of projectiles (current, time-fuze, illuminating, smoke, with conventional propulsion, rocket, with built-in gas generator, etc.. Instead of previous solutions, where a trajectory calculation of the fire control system was done by approximate methods, in this BM the trajectory calculation is made by the same model with the same data as for a weapon and ammunition in the process of creating a firing table. The data used in the fire control system are made simultaneously with the preparation of firing tables for a particular tool and associated ammunition,. A modified model of particle, standardized at the NATO level, is also used. Taking into account the meteorological situation, before the trajectory calculation is done, a relative position of the target in relation to the position of the tool should be determined. A selection or loading check is carried out (possibility of reaching a given target as well as the point at which the

  15. Flip, flop and fly: modulated motor control and highly variable movement patterns of autotomized gecko tails.

    Science.gov (United States)

    Higham, Timothy E; Russell, Anthony P

    2010-02-23

    Many animals lose and regenerate appendages, and tail autotomy in lizards is an extremely well-studied example of this. Whereas the energetic, ecological and functional ramifications of tail loss for many lizards have been extensively documented, little is known about the behaviour and neuromuscular control of the autotomized tail. We used electromyography and high-speed video to quantify the motor control and movement patterns of autotomized tails of leopard geckos (Eublepharis macularius). In addition to rhythmic swinging, we show that they exhibit extremely complex movement patterns for up to 30 min following autotomy, including acrobatic flips up to 3 cm in height. Unlike the output of most central pattern generators (CPGs), muscular control of the tail is variable and can be arrhythmic. We suggest that the gecko tail is well suited for studies involving CPGs, given that this spinal preparation is naturally occurring, requires no surgery and exhibits complex modulation.

  16. Evaluation and application of a fast module in a PLC based interlock and control system

    International Nuclear Information System (INIS)

    Zaera-Sanz, M

    2009-01-01

    The LHC Beam Interlock system requires a controller performing a simple matrix function to collect the different beam dump requests. To satisfy the expected safety level of the Interlock, the system should be robust and reliable. The PLC is a promising candidate to fulfil both aspects but too slow to meet the expected response time which is of the order of μseconds. Siemens has introduced a 'so called' fast module (FM352-5 Boolean Processor). It provides independent and extremely fast control of a process within a larger control system using an onboard processor, a Field Programmable Gate Array (FPGA), to execute code in parallel which results in extremely fast scan times. It is interesting to investigate its features and to evaluate it as a possible candidate for the beam interlock system. This paper publishes the results of this study. As well, this paper could be useful for other applications requiring fast processing using a PLC.

  17. Analysis and design of a standardized control module for switching regulators

    Science.gov (United States)

    Lee, F. C.; Mahmoud, M. F.; Yu, Y.; Kolecki, J. C.

    1982-07-01

    Three basic switching regulators: buck, boost, and buck/boost, employing a multiloop standardized control module (SCM) were characterized by a common small signal block diagram. Employing the unified model, regulator performances such as stability, audiosusceptibility, output impedance, and step load transient are analyzed and key performance indexes are expressed in simple analytical forms. More importantly, the performance characteristics of all three regulators are shown to enjoy common properties due to the unique SCM control scheme which nullifies the positive zero and provides adaptive compensation to the moving poles of the boost and buck/boost converters. This allows a simple unified design procedure to be devised for selecting the key SCM control parameters for an arbitrarily given power stage configuration and parameter values, such that all regulator performance specifications can be met and optimized concurrently in a single design attempt.

  18. Optical techniques to feed and control GaAs MMIC modules for phased array antenna applications

    Science.gov (United States)

    Bhasin, K. B.; Anzic, G.; Kunath, R. R.; Connolly, D. J.

    1986-01-01

    A complex signal distribution system is required to feed and control GaAs monolithic microwave integrated circuits (MMICs) for phased array antenna applications above 20 GHz. Each MMIC module will require one or more RF lines, one or more bias voltage lines, and digital lines to provide a minimum of 10 bits of combined phase and gain control information. In a closely spaced array, the routing of these multiple lines presents difficult topology problems as well as a high probability of signal interference. To overcome GaAs MMIC phased array signal distribution problems optical fibers interconnected to monolithically integrated optical components with GaAs MMIC array elements are proposed as a solution. System architecture considerations using optical fibers are described. The analog and digital optical links to respectively feed and control MMIC elements are analyzed. It is concluded that a fiber optic network will reduce weight and complexity, and increase reliability and performance, but higher power will be required.

  19. Controlled ecological life support systems: Development of a plant growth module

    Science.gov (United States)

    Averner, Mel M.; Macelroy, Robert D.; Smernoff, David T.

    1987-01-01

    An effort was made to begin defining the scientific and technical requirements for the design and construction of a ground-based plant growth facility. In particular, science design criteria for the Plant Growth Module (PGM) of the Controlled Ecological Life Support System (CELSS) were determined in the following areas: (1) irradiation parameters and associated equipment affecting plant growth; (2) air flow; (3) planting, culture, and harvest techniques; (4) carbon dioxide; (5) temperature and relative humidity; (6) oxygen; (7) construction materials and access; (8) volatile compounds; (9) bacteria, sterilization, and filtration; (10) nutrient application systems; (11) nutrient monitoring; and (12) nutrient pH and conductivity.

  20. Distributed detection and control of defective thermoelectric generation modules using sensor nodes

    DEFF Research Database (Denmark)

    Chen, Min

    2014-01-01

    are described, respectively. Defective and potentially healing conditions are dynamically monitored by a voltage sensor node and a temperature sensor node, both of which can judge the defective TEM and decide the related switching actions in a nearly independent way. The periodical wireless transmission from......To maximize the energy productivity, effective in-field detection and real-time control of defective thermoelectric modules (TEMs) are critical in constituting a thermoelectric generation system (TEGS). In this paper, autonomous and distributed sensor nodes are designed to implement the wireless...... a considerable power improvement is illustrated with the proposed measuring method and setup....

  1. A Predictive-Control-Based Over-Modulation Method for Conventional Matrix Converters

    DEFF Research Database (Denmark)

    Zhang, Guanguan; Yang, Jian; Sun, Yao

    2018-01-01

    To increase the voltage transfer ratio of the matrix converter and improve the input/output current performance simultaneously, an over-modulation method based on predictive control is proposed in this paper, where the weighting factor is selected by an automatic adjusting mechanism, which is able...... to further enhance the system performance promptly. This method has advantages like the maximum voltage transfer ratio can reach 0.987 in the experiments; the total harmonic distortion of the input and output current are reduced, and the losses in the matrix converter are decreased. Moreover, the specific...

  2. A DC-Link Modulation Scheme with Phase-Shifted Current Control for Harmonic Cancellations in Multidrive Applications

    DEFF Research Database (Denmark)

    Yang, Yongheng; Davari, Pooya; Zare, Firuz

    2016-01-01

    of a new DC link modulation scheme with a phase-shifted current control enabled by the SCR. The DC-link current modulation scheme is implemented by adding and subtracting specific modulation levels, which makes the total currents drawn from the grid “multi-level”, resulting in an improved current quality......This letter proposes a harmonic mitigation strategy to cancel out current harmonics induced by the front-end rectifiers in multi-drive systems, which consist of diode rectifiers, Silicon-Controlled Rectifiers (SCR), and boost converters in the DC-link. The proposed strategy is a combination...

  3. A quantitative analysis of transtensional margin width

    Science.gov (United States)

    Jeanniot, Ludovic; Buiter, Susanne J. H.

    2018-06-01

    Continental rifted margins show variations between a few hundred to almost a thousand kilometres in their conjugated widths from the relatively undisturbed continent to the oceanic crust. Analogue and numerical modelling results suggest that the conjugated width of rifted margins may have a relationship to their obliquity of divergence, with narrower margins occurring for higher obliquity. We here test this prediction by analysing the obliquity and rift width for 26 segments of transtensional conjugate rifted margins in the Atlantic and Indian Oceans. We use the plate reconstruction software GPlates (http://www.gplates.org) for different plate rotation models to estimate the direction and magnitude of rifting from the initial phases of continental rifting until breakup. Our rift width corresponds to the distance between the onshore maximum topography and the last identified continental crust. We find a weak positive correlation between the obliquity of rifting and rift width. Highly oblique margins are narrower than orthogonal margins, as expected from analogue and numerical models. We find no relationships between rift obliquities and rift duration nor the presence or absence of Large Igneous Provinces (LIPs).

  4. Seasonal and hormonal modulation of neurotransmitter systems in the song control circuit.

    Science.gov (United States)

    Ball, Gregory F; Balthazart, Jacques

    2010-03-01

    In the years following the discovery of the song system, it was realized that this specialized circuit controlling learned vocalizations in songbirds (a) constitutes a specific target for sex steroid hormone action and expresses androgen and (for some nuclei) estrogen receptors, (b) exhibits a chemical neuroanatomical pattern consisting in a differential expression of various neuropeptides and neurotransmitters receptors as compared to surrounding structures and (c) shows pronounced seasonal variations in volume and physiology based, at least in the case of HVC, on a seasonal change in neuron recruitment and survival. During the past 30 years numerous studies have investigated how seasonal changes, transduced largely but not exclusively through changes in sex steroid concentrations, affect singing frequency and quality by modulating the structure and activity of the song control circuit. These studies showed that testosterone or its metabolite estradiol, control seasonal variation in singing quality by a direct action on song control nuclei. These studies also gave rise to the hypothesis that the probability of song production in response to a given stimulus (i.e. its motivation) is controlled through effects on the medial preoptic area and on catecholaminergic cell groups that project to song control nuclei. Selective pharmacological manipulations confirmed that the noradrenergic system indeed plays a role in the control of singing behavior. More experimental work is, however, needed to identify specific genes related to neurotransmission that are regulated by steroids in functionally defined brain areas to enhance different aspects of song behavior. Copyright 2009. Published by Elsevier B.V.

  5. A Development of the Calibration Tool Applied on Analog I/O Modules for Safety-related Controller

    International Nuclear Information System (INIS)

    Kim, Jong-Kyun; Yun, Dong-Hwa; Lee, Myeong-Kyun; Yoo, Kwan-Woo

    2016-01-01

    The purpose of this paper is to develop the calibration tool for analog input/output(I/O) modules. Those modules are components in POSAFE-Q which is a programmable logic controller(PLC) that has been developed for the evaluation of safety-related. In this paper, performance improvement of analog I/O modules is presented by developing and applying the calibration tool for each channel in analog I/O modules. With this tool, the input signal to an analog input module and the output signal from an analog output module are able to be satisfied with a reference value of sensor type and an accuracy of all modules. With RS-232 communication, the manual calibration tool is developed for analog I/O modules of an existing and up-to-date version in POSAFE-Q PLC. As a result of applying this tool, the converted value is performant for a type of input sensor and an accuracy of analog I/O modules

  6. The decay width of stringy hadrons

    Directory of Open Access Journals (Sweden)

    Jacob Sonnenschein

    2018-02-01

    We fit the theoretical decay width to experimental data for mesons on the trajectories of ρ, ω, π, η, K⁎, ϕ, D, and Ds⁎, and of the baryons N, Δ, Λ, and Σ. We examine both the linearity in L and the exponential suppression factor. The linearity was found to agree with the data well for mesons but less for baryons. The extracted coefficient for mesons A=0.095±0.015 is indeed quite universal. The exponential suppression was applied to both strong and radiative decays. We discuss the relation with string fragmentation and jet formation. We extract the quark–diquark structure of baryons from their decays. A stringy mechanism for Zweig suppressed decays of quarkonia is proposed and is shown to reproduce the decay width of ϒ states. The dependence of the width on spin and flavor symmetry is discussed. We further apply this model to the decays of glueballs and exotic hadrons.

  7. A voltage control method for an active capacitive DC-link module with series-connected circuit

    DEFF Research Database (Denmark)

    Wang, Haoran; Wang, Huai; Blaabjerg, Frede

    2017-01-01

    Many efforts have been made to improve the performance of power electronic systems with active capacitive DC-link module in terms of power density as well as reliability. One of the attractive solution is an active capacitive DC-link with the series-connected circuit because of handling small......-rated power. However, in the existing control method of this circuit, the DC-link current of the backward-stage or forward-stage need to be sensed for extracting the ripple components, which limits the flexibility of the active DC-link module. Thus, in this paper, a voltage control method of an active...... capacitive DC-link module is proposed. Current sensor at the DC-link will be cancel from the circuit. The controller of the series-connected circuit requires internal voltage signals of the DC-link module only, making it possible to be fully independent without any additional connection to the main circuit...

  8. The decay width of stringy hadrons

    Science.gov (United States)

    Sonnenschein, Jacob; Weissman, Dorin

    2018-02-01

    In this paper we further develop a string model of hadrons by computing their strong decay widths and comparing them to experiment. The main decay mechanism is that of a string splitting into two strings. The corresponding total decay width behaves as Γ = π/2 ATL where T and L are the tension and length of the string and A is a dimensionless universal constant. We show that this result holds for a bosonic string not only in the critical dimension. The partial width of a given decay mode is given by Γi / Γ =Φi exp ⁡ (- 2 πCmsep2 / T) where Φi is a phase space factor, msep is the mass of the "quark" and "antiquark" created at the splitting point, and C is a dimensionless coefficient close to unity. Based on the spectra of hadrons we observe that their (modified) Regge trajectories are characterized by a negative intercept. This implies a repulsive Casimir force that gives the string a "zero point length". We fit the theoretical decay width to experimental data for mesons on the trajectories of ρ, ω, π, η, K*, ϕ, D, and Ds*, and of the baryons N, Δ, Λ, and Σ. We examine both the linearity in L and the exponential suppression factor. The linearity was found to agree with the data well for mesons but less for baryons. The extracted coefficient for mesons A = 0.095 ± 0.015 is indeed quite universal. The exponential suppression was applied to both strong and radiative decays. We discuss the relation with string fragmentation and jet formation. We extract the quark-diquark structure of baryons from their decays. A stringy mechanism for Zweig suppressed decays of quarkonia is proposed and is shown to reproduce the decay width of ϒ states. The dependence of the width on spin and flavor symmetry is discussed. We further apply this model to the decays of glueballs and exotic hadrons.

  9. Kinetic Control of Aqueous Hydrolysis: Modulating Structure/Property Relationships in Inorganic Crystals

    Science.gov (United States)

    Neilson, James R.

    2011-12-01

    A grand challenge in materials science and chemistry revolves around the preparation of materials with desired properties by controlling structure on multiple length scales. Biology approaches this challenge by evolving tactics to transform soluble precursors into materials and composites with macro-scale and atomic precision. Studies of biomineralization in siliceous sponges led to the discovery of slow, catalytic hydrolysis of molecular precursors in the biogenesis of silica skeletal elements with well defined micro- and nano-scale architectures. However, the role of aqueous hydrolysis in the limit of kinetic control is not well understood; this allows us to form a central hypothesis: that the kinetics of hydrolysis modulate the structures of materials and their properties. As a model system, the diffusion of a simple hydrolytic catalyst (such as ammonia) across an air-water interface into a metal salt solution reproduces some aspects of the chemistry found in biomineralization, namely kinetic and vectorial control. Variation of the catalyst concentration modulates the hydrolysis rate, and thus alters the resulting structure of the inorganic crystals. Using aqueous solutions of cobalt(II) chloride, each product (cobalt hydroxide chloride) forms with a unique composition, despite being prepared from identical mother liquors. Synchrotron X-ray total scattering methods are needed to locate the atomic positions in the material, which are not aptly described by a traditional crystallographic unit cell due to structural disorder. Detailed definition of the structure confirms that the hydrolysis conditions systematically modulate the arrangement of atoms in the lattice. This tightly coupled control of crystal formation and knowledge of local and average structures of these materials provides insight into the unusual magnetic properties of these cobalt hydroxides. The compounds studied show significant and open magnetization loops with little variation with composition

  10. Effective spectrum width of the synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Bagrov, V. G., E-mail: bagrov@phys.tsu.ru [Department of Physics, Tomsk State University, Tomsk (Russian Federation); Institute of High Current Electronics, SB RAS, Tomsk (Russian Federation); Gitman, D. M., E-mail: gitman@if.usp.br [Department of Physics, Tomsk State University, Tomsk (Russian Federation); Institute of Physics, University of São Paulo, São Paulo (Brazil); P.N.Lebedev Physical Institute, Moscow (Russian Federation); Levin, A. D., E-mail: alevin@if.usp.br [Institute of Physics, University of São Paulo, São Paulo (Brazil); Loginov, A. S.; Saprykin, A. D. [Department of Physics, Tomsk State University, Tomsk (Russian Federation)

    2015-11-25

    For an exact quantitative description of spectral properties of synchrotron radiation (SR), the concept of effective width of the spectrum is introduced. In the most interesting case, which corresponds to the ultrarelativistic limit of SR, the effective width of the spectrum is calculated for the polarization components, and new physically important quantitative information on the structure of spectral distributions is obtained. For the first time, the spectral distribution for the circular polarization component of the SR for the upper half-space is obtained within classical theory.

  11. Effective spectrum width of the synchrotron radiation

    International Nuclear Information System (INIS)

    Bagrov, V. G.; Gitman, D. M.; Levin, A. D.; Loginov, A. S.; Saprykin, A. D.

    2015-01-01

    For an exact quantitative description of spectral properties of synchrotron radiation (SR), the concept of effective width of the spectrum is introduced. In the most interesting case, which corresponds to the ultrarelativistic limit of SR, the effective width of the spectrum is calculated for the polarization components, and new physically important quantitative information on the structure of spectral distributions is obtained. For the first time, the spectral distribution for the circular polarization component of the SR for the upper half-space is obtained within classical theory

  12. Effective spectrum width of the synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Bagrov, V.G. [Tomsk State University, Department of Physics, Tomsk (Russian Federation); SB RAS, Institute of High Current Electronics, Tomsk (Russian Federation); Gitman, D.M. [Tomsk State University, Department of Physics, Tomsk (Russian Federation); University of Sao Paulo, Institute of Physics, Sao Paulo (Brazil); P.N. Lebedev Physical Institute, Moscow (Russian Federation); Levin, A.D. [University of Sao Paulo, Institute of Physics, Sao Paulo (Brazil); Loginov, A.S.; Saprykin, A.D. [Tomsk State University, Department of Physics, Tomsk (Russian Federation)

    2015-11-15

    For an exact quantitative description of spectral properties of synchrotron radiation (SR), the concept of effective width of the spectrum is introduced. In the most interesting case, which corresponds to the ultrarelativistic limit of SR, the effective width of the spectrum is calculated for the polarization components, and new physically important quantitative information on the structure of spectral distributions is obtained. For the first time, the spectral distribution for the circular polarization component of the SR for the upper half-space is obtained within classical theory. (orig.)

  13. Temperature dependence of giant dipole resonance width

    International Nuclear Information System (INIS)

    Vdovin, A.I.; Storozhenko, A.N.

    2005-01-01

    The quasiparticle-phonon nuclear model extended to finite temperature within the framework of the thermo field dynamics is applied to calculate a temperature dependence of the spreading width Γ d own of a giant dipole resonance. Numerical calculations are made for 12S n and 208 Pb nuclei. It is found that the width Γ d own increases with T. The reason of this effect is discussed as well as a relation of the present approach to other ones existing in the literature

  14. Line width of Josephson flux flow oscillators

    DEFF Research Database (Denmark)

    Koshelets, V.P.; Dmitriev, P.N.; Sobolev, A.S.

    2002-01-01

    to be proven before one initiates real FFO applications. To achieve this goal a comprehensive set of line width measurements of the FFO operating in different regimes has been performed. FFOs with tapered shape have been successfully implemented in order to avoid the superfine resonant structure with voltage...... spacing of about 20 nV and extremely low differential resistance, recently observed in the IVC of the standard rectangular geometry. The obtained results have been compared with existing theories and FFO models in order to understand and possibly eliminate excess noise in the FFO. The intrinsic line width...

  15. STUDIES AND EXPERIMENTAL RESEARCH CONCERNING THE PERFORMANCES OF THE INTERNAL COMBUSTION ENGINE, CONTROLLED OVER THE POWERTRAIN CONTROL MODULE

    Directory of Open Access Journals (Sweden)

    Narcis URICANU

    2012-05-01

    Full Text Available the paper present how can be controlled a road vehicle through a powertrain control module, a type of ECU, programmable ECU (Electronic Control Unit, when we want to increase the performances of the engine, compared with the standard performances of the engine. The programmable ECU is a control system which replaces the ECU from the vehicle and is able to manage, better than the standard ECU, the behaviour of the spark ignition engine on increasing the performances. Sports cars need to obtain the best performances from them engine, the specific regimes at which them must function impose certain limits which will be achieved during the competition. Nowadays the vehicles designers and engineering, working for the production cars, have adopted many solutions from the race cars area, due to the advantage offered by these elements (lightweight materials, fasts responses, high speeds and system like programmable ECU. To obtain more power on the engine, we have to find and applied the best solution concerning the internal combustion processes and the consequences concerning the exhaust. This papers present who can be increased the performances of the spark ignition engine through the air-flow ratio, controlled by the programmable ECU and with the sensors help, like water temperature sensor, intake air temperature sensor, throttle position sensor, lambda sensor

  16. Characterization and quality control of avalanche photodiode arrays for the Clear-PEM detector modules

    International Nuclear Information System (INIS)

    Abreu, Conceicao; Amaral, Pedro; Carrico, Bruno; Ferreira, Miguel; Luyten, Joan; Moura, Rui; Ortigao, Catarina; Rato, Pedro; Varela, Joao

    2007-01-01

    Clear-PEM is a Positron Emission Mammography (PEM) prototype being developed in the framework of the Crystal Clear Collaboration at CERN. This device is a dedicated PET camera for mammography, based on LYSO:Ce scintillator crystals, Avalanche PhotoDiodes (APD) and a fast, low-noise electronics readout system, designed to examine both the breast and the axillary lymph node areas, and aiming at the detection of tumors down to 2 mm in diameter. The prototype has two planar detector heads, each composed of 96 detector modules. The Clear-PEM detector module is composed of a matrix of 32 identical 2x2x20 mm 3 LYSO:Ce crystals read at both ends by Hamamatsu S8550 APD arrays (4x8) for Depth-of-Interaction (DoI) capability. The APD arrays were characterized by the measurement of gain and dark current as a function of bias voltage, under controlled temperature conditions. Two independent setups were used. The full set of 398 APD arrays followed a well-defined quality control (QC) protocol, aiming at the rejection of arrays not complying within defined specifications. From a total of 398 arrays, only 2 (0.5%) were rejected, reassuring the trust in these detectors for prototype assembly and future developments

  17. Controlling Fringe Sensitivity of Electro-Optic Holography Systems Using Laser Diode Current Modulation

    Science.gov (United States)

    Bybee, Shannon J.

    2001-01-01

    Electro-Optic Holography (EOH) is a non-intrusive, laser-based, displacement measurement technique capable of static and dynamic displacement measurements. EOH is an optical interference technique in which fringe patterns that represent displacement contour maps are generated. At excessively large displacements the fringe density may be so great that individual fringes are not resolvable using typical EOH techniques. This thesis focuses on the development and implementation of a method for controlling the sensitivity of the EOH system. This method is known as Frequency Translated Electro-Optic Holography (FTEOH). It was determined that by modulating the current source of the laser diode at integer multiples of the object vibration, the fringe pattern is governed by higher order Bessel function of the first kind and the number of fringes that represent a given displacement can be controlled. The reduction of fringes is theoretically unlimited but physically limited by the frequency bandwidth of the signal generator, providing modulation to the laser diode. Although this research technique has been verified theoretically and experimentally in this thesis, due to the current laser diode capabilities it is a tedious and time consuming process to acquire data using the FTEOH technique.

  18. The Arabidopsis SWI/SNF protein BAF60 mediates seedling growth control by modulating DNA accessibility

    KAUST Repository

    Jégu, Teddy

    2017-06-15

    Plant adaptive responses to changing environments involve complex molecular interplays between intrinsic and external signals. Whilst much is known on the signaling components mediating diurnal, light, and temperature controls on plant development, their influence on chromatin-based transcriptional controls remains poorly explored.In this study we show that a SWI/SNF chromatin remodeler subunit, BAF60, represses seedling growth by modulating DNA accessibility of hypocotyl cell size regulatory genes. BAF60 binds nucleosome-free regions of multiple G box-containing genes, opposing in cis the promoting effect of the photomorphogenic and thermomorphogenic regulator Phytochrome Interacting Factor 4 (PIF4) on hypocotyl elongation. Furthermore, BAF60 expression level is regulated in response to light and daily rhythms.These results unveil a short path between a chromatin remodeler and a signaling component to fine-tune plant morphogenesis in response to environmental conditions.

  19. FPGA-based implementation of a fuzzy controller (MPPT) for photovoltaic module

    International Nuclear Information System (INIS)

    Messai, A.; Mellit, A.; Massi Pavan, A.; Guessoum, A.; Mekki, H.

    2011-01-01

    Research highlights: → FL-MPPT controller is implemented on FPGA. → Results obtained with ModelSim show a satisfactory performance. → Results will be useful for future development in PV. -- Abstract: This paper describes the hardware implementation of a two-inputs one-output digital Fuzzy Logic Controller (FLC) on a Xilinx reconfigurable Field-Programmable Gate Array (FPGA) using VHDL Hardware Description Language. The FLC is designed for seeking the maximum power point deliverable by a photovoltaic module using the measures of the photovoltaic current and voltage. The simulation results obtained with ModelSim Xilinx Edition-III show a satisfactory performance with a good agreement between the expected and the obtained values.

  20. The Arabidopsis SWI/SNF protein BAF60 mediates seedling growth control by modulating DNA accessibility

    KAUST Repository

    Jé gu, Teddy; Veluchamy, Alaguraj; Ramirez Prado, Juan Sebastian; Rizzi-Paillet, Charley; Perez, Magalie; Lhomme, Anaï s; Latrasse, David; Coleno, Emeline; Vicaire, Serge; Legras, Sté phanie; Jost, Bernard; Rougé e, Martin; Barneche, Fredy; Bergounioux, Catherine; Crespi, Martin; Mahfouz, Magdy M.; Hirt, Heribert; Raynaud, Cé cile; Benhamed, Moussa

    2017-01-01

    Plant adaptive responses to changing environments involve complex molecular interplays between intrinsic and external signals. Whilst much is known on the signaling components mediating diurnal, light, and temperature controls on plant development, their influence on chromatin-based transcriptional controls remains poorly explored.In this study we show that a SWI/SNF chromatin remodeler subunit, BAF60, represses seedling growth by modulating DNA accessibility of hypocotyl cell size regulatory genes. BAF60 binds nucleosome-free regions of multiple G box-containing genes, opposing in cis the promoting effect of the photomorphogenic and thermomorphogenic regulator Phytochrome Interacting Factor 4 (PIF4) on hypocotyl elongation. Furthermore, BAF60 expression level is regulated in response to light and daily rhythms.These results unveil a short path between a chromatin remodeler and a signaling component to fine-tune plant morphogenesis in response to environmental conditions.

  1. FPGA-based implementation of a fuzzy controller (MPPT) for photovoltaic module

    Energy Technology Data Exchange (ETDEWEB)

    Messai, A. [CRNB Ain Oussera, P.O. Box 180, 17200, Djelfa (Algeria); Department of Electronics, Faculty of Sciences Engineering, Blida University, Blida 90000 (Algeria); Mellit, A., E-mail: a.mellit@yahoo.co.u [Department of Electronics, Faculty of Sciences and Technology, Jijel University, Ouled-aissa, P.O. Box 98, Jijel 18000 (Algeria); Department of Electronics, Faculty of Sciences Engineering, Blida University, Blida 90000 (Algeria); Massi Pavan, A. [Department of Materials and Natural Resources, University of Trieste, Via A. Valerio, 2 - 34127 Trieste (Italy); Guessoum, A. [Department of Electronics, Faculty of Sciences Engineering, Blida University, Blida 90000 (Algeria); Mekki, H. [CRNB Ain Oussera, P.O. Box 180, 17200, Djelfa (Algeria); Department of Electronics, Faculty of Sciences Engineering, Blida University, Blida 90000 (Algeria)

    2011-07-15

    Research highlights: {yields} FL-MPPT controller is implemented on FPGA. {yields} Results obtained with ModelSim show a satisfactory performance. {yields} Results will be useful for future development in PV. -- Abstract: This paper describes the hardware implementation of a two-inputs one-output digital Fuzzy Logic Controller (FLC) on a Xilinx reconfigurable Field-Programmable Gate Array (FPGA) using VHDL Hardware Description Language. The FLC is designed for seeking the maximum power point deliverable by a photovoltaic module using the measures of the photovoltaic current and voltage. The simulation results obtained with ModelSim Xilinx Edition-III show a satisfactory performance with a good agreement between the expected and the obtained values.

  2. Numerical examination of temperature control in helium-cooled high flux test module of IFMIF

    International Nuclear Information System (INIS)

    Ebara, Shinji; Yokomine, Takehiko; Shimizu, Akihiko

    2007-01-01

    For long term irradiation of the International Fusion Materials Irradiation Facility (IFMIF), test specimens are needed to retain constant temperature to avoid change of its irradiation characteristics. The constant temperatures control is one of the most challenging issues for the IFMIF test facilities. We have proposed a new concept of test module which is capable of precisely measuring temperature, keeping uniform temperature with enhanced cooling performance. In the system according to the new design, cooling performances and temperature distributions of specimens were examined numerically under diverse conditions. Some transient behaviors corresponding to the prescribed temperature control mode were perseveringly simulated. It was confirmed that the thermal characteristics of the new design satisfied the severe requirement of IFMIF

  3. E-plane Beam Width Reconfigurable Dipole Antenna with Tunable Parasitic Strip

    DEFF Research Database (Denmark)

    Zhang, Jin; Zhang, Shuai; Pedersen, Gert F.

    2018-01-01

    A 3-dB E-plane beam width (EPBW) reconfig- urable dipole antenna is proposed in this paper. By introducing a tunable C-shape strip, the EPBW of the dipole antenna can switch in three different modes: narrow, middle and wide. Three pairs of PIN diodes are used for controlling. The beam width tuning...

  4. A novel oscillation control for MEMS vibratory gyroscopes using a modified electromechanical amplitude modulation technique

    International Nuclear Information System (INIS)

    Ma, Wei; Lin, Yiyu; Liu, Siqi; Zheng, Xudong; Jin, Zhonghe

    2017-01-01

    This paper reports a novel oscillation control algorithm for MEMS vibratory gyroscopes using a modified electromechanical amplitude modulation (MEAM) technique, which enhances the robustness against the frequency variation of the driving mode, compared to the conventional EAM (CEAM) scheme. In this approach, the carrier voltage exerted on the proof mass is frequency-modulated by the drive resonant frequency. Accordingly, the pick-up signal from the interface circuit involves a constant-frequency component that contains the amplitude and phase information of the vibration displacement. In other words, this informational detection signal is independent of the mechanical resonant frequency, which varies due to different batches, imprecise micro-fabrication and changing environmental temperature. In this paper, the automatic gain control loop together with the phase-locked loop are simultaneously analyzed using the averaging method and Routh–Hurwitz criterion, deriving the stability condition and the parameter optimization rules of the transient response. Then, a simulation model based on the real system is set up to evaluate the control algorithm. Further, the proposed MEAM method is tested using a field-programmable-gate-array based digital platform on a capacitive vibratory gyroscope. By optimizing the control parameters, the transient response of the drive amplitude reveals a settling time of 45.2 ms without overshoot, according well with the theoretical prediction and simulation results. The first measurement results show that the amplitude variance of the drive displacement is 12 ppm in an hour while the phase standard deviation is as low as 0.0004°. The mode-split gyroscope operating under atmospheric pressure demonstrates an outstanding performance. By virtue of the proposed MEAM method, the bias instability and angle random walk are measured to be 0.9° h −1 (improved by 2.4 times compared to the CEAM method) and 0.068° (√h) −1 (improved by 1

  5. Development and Validation of a Controlled Virtual Environment for Guidance, Navigation and Control of Quadrotor UAV

    Science.gov (United States)

    2013-09-01

    Width Modulation QuarC Quanser Real-time Control RC Remote Controlled RPV Remotely Piloted Vehicles SLAM Simultaneous Localization and Mapping UAV...development of the following systems: 1. Navigation (GPS, Lidar , etc.) 2. Communication (Datalink) 3. Ground Control Station (GUI, software programming

  6. Reward-Modulated Hebbian Plasticity as Leverage for Partially Embodied Control in Compliant Robotics

    Science.gov (United States)

    Burms, Jeroen; Caluwaerts, Ken; Dambre, Joni

    2015-01-01

    In embodied computation (or morphological computation), part of the complexity of motor control is offloaded to the body dynamics. We demonstrate that a simple Hebbian-like learning rule can be used to train systems with (partial) embodiment, and can be extended outside of the scope of traditional neural networks. To this end, we apply the learning rule to optimize the connection weights of recurrent neural networks with different topologies and for various tasks. We then apply this learning rule to a simulated compliant tensegrity robot by optimizing static feedback controllers that directly exploit the dynamics of the robot body. This leads to partially embodied controllers, i.e., hybrid controllers that naturally integrate the computations that are performed by the robot body into a neural network architecture. Our results demonstrate the universal applicability of reward-modulated Hebbian learning. Furthermore, they demonstrate the robustness of systems trained with the learning rule. This study strengthens our belief that compliant robots should or can be seen as computational units, instead of dumb hardware that needs a complex controller. This link between compliant robotics and neural networks is also the main reason for our search for simple universal learning rules for both neural networks and robotics. PMID:26347645

  7. Designing Diameter-Modulated Heterostructure Nanowires of PbTe/Te by Controlled Dewetting.

    Science.gov (United States)

    Kumar, Abinash; Kundu, Subhajit; Samantaray, Debadarshini; Kundu, Paromita; Zanaga, Daniele; Bals, Sara; Ravishankar, N

    2017-12-13

    Heterostructures consisting of semiconductors with controlled morphology and interfaces find applications in many fields. A range of axial, radial, and diameter-modulated nanostructures have been synthesized primarily using vapor phase methods. Here, we present a simple wet chemical routine to synthesize heterostructures of PbTe/Te using Te nanowires as templates. A morphology evolution study for the formation of these heterostructures has been performed. On the basis of these control experiments, a pathway for the formation of these nanostructures is proposed. Reduction of a Pb precursor to Pb on Te nanowire templates followed by interdiffusion of Pb/Te leads to the formation of a thin shell of PbTe on the Te wires. Controlled dewetting of the thin shell leads to the formation of cube-shaped PbTe that is periodically arranged on the Te wires. Using control experiments, we show that different reactions parameters like rate of addition of the reducing agent, concentration of Pb precursor and thickness of initial Te nanowire play a critical role in controlling the spacing between the PbTe cubes on the Te wires. Using simple surface energy arguments, we propose a mechanism for the formation of the hybrid. The principles presented are general and can be exploited for the synthesis of other nanoscale heterostructures.

  8. Permanent magnet DC motor control by using arduino and motor drive module BTS7960

    Science.gov (United States)

    Syukriyadin, S.; Syahrizal, S.; Mansur, G.; Ramadhan, H. P.

    2018-05-01

    This study proposes a control system for permanent magnet DC (PMDC) motor. PMDC drive control system has two critical parameters: control and monitoring. Control system includes rotation speed control and direction of rotation of motor using motor drive module BTS7960. The PWM signal has a fixed frequency of waves with varying duty cycles (between 0% and 100%), so the motor rotation can be regulated gradually using a potentiometer already programmed on the Arduino Uno board. The motor rotation direction setting uses the H-bridge circuit method using a 3-way switch to set the direction of forward-reverse rotation of the motor. The monitoring system includes measurements of rotational speed, current, and voltage. Motor rotation speed can be adjusted from the armature voltage settings through the duty cycle PWM setting so that the motor speed can be increased or decreased by the desired duty cycle. From the unload PMDC motor test results it has also been shown that the torque of the motor is relatively constant when there is a change in speed from low rpm to high rpm or vice versa.

  9. Flyback CCM inverter for AC module applications: iterative learning control and convergence analysis

    Science.gov (United States)

    Lee, Sung-Ho; Kim, Minsung

    2017-12-01

    This paper presents an iterative learning controller (ILC) for an interleaved flyback inverter operating in continuous conduction mode (CCM). The flyback CCM inverter features small output ripple current, high efficiency, and low cost, and hence it is well suited for photovoltaic power applications. However, it exhibits the non-minimum phase behaviour, because its transfer function from control duty to output current has the right-half-plane (RHP) zero. Moreover, the flyback CCM inverter suffers from the time-varying grid voltage disturbance. Thus, conventional control scheme results in inaccurate output tracking. To overcome these problems, the ILC is first developed and applied to the flyback inverter operating in CCM. The ILC makes use of both predictive and current learning terms which help the system output to converge to the reference trajectory. We take into account the nonlinear averaged model and use it to construct the proposed controller. It is proven that the system output globally converges to the reference trajectory in the absence of state disturbances, output noises, or initial state errors. Numerical simulations are performed to validate the proposed control scheme, and experiments using 400-W AC module prototype are carried out to demonstrate its practical feasibility.

  10. Radiative width of molecular-cluster states

    International Nuclear Information System (INIS)

    Alhassid, Y.; Gai, M.; Bertsch, G.F.

    1982-01-01

    Molecular states are characterized by enhanced electromagnetic deexcitations of many different multipolarities. The expected enhancement of E1, E2, and E3 transitions is examined by deriving molecular sum rules for radiative deexcitation widths and via a dimensionality approach. The enhancement of the E1 transitions is the most striking

  11. Bounding the Higgs boson width through interferometry.

    Science.gov (United States)

    Dixon, Lance J; Li, Ye

    2013-09-13

    We study the change in the diphoton-invariant-mass distribution for Higgs boson decays to two photons, due to interference between the Higgs resonance in gluon fusion and the continuum background amplitude for gg→γγ. Previously, the apparent Higgs mass was found to shift by around 100 MeV in the standard model in the leading-order approximation, which may potentially be experimentally observable. We compute the next-to-leading-order QCD corrections to the apparent mass shift, which reduce it by about 40%. The apparent mass shift may provide a way to measure, or at least bound, the Higgs boson width at the Large Hadron Collider through "interferometry." We investigate how the shift depends on the Higgs width, in a model that maintains constant Higgs boson signal yields. At Higgs widths above 30 MeV, the mass shift is over 200 MeV and increases with the square root of the width. The apparent mass shift could be measured by comparing with the ZZ* channel, where the shift is much smaller. It might be possible to measure the shift more accurately by exploiting its strong dependence on the Higgs transverse momentum.

  12. Practical algorithms for linear boolean-width

    NARCIS (Netherlands)

    ten Brinke, C.B.; van Houten, F.J.P.; Bodlaender, H.L.

    2015-01-01

    In this paper, we give a number of new exact algorithms and heuristics to compute linear boolean decompositions, and experimentally evaluate these algorithms. The experimental evaluation shows that significant improvements can be made with respect to running time without increasing the width of the

  13. Practical algorithms for linear Boolean-width

    NARCIS (Netherlands)

    ten Brinke, C.B.; van Houten, F.J.P.; Bodlaender, H.L.

    2015-01-01

    In this paper, we give a number of new exact algorithms and heuristics to compute linear boolean decompositions, and experimentally evaluate these algorithms. The experimental evaluation shows that significant improvements can be made with respect to running time without increasing the width of the

  14. A Novel Modulation Function-Based Control of Modular Multilevel Converters for High Voltage Direct Current Transmission Systems

    Directory of Open Access Journals (Sweden)

    Majid Mehrasa

    2016-10-01

    Full Text Available In this paper, a novel modulation function-based method including analyses of the modulation index and phase is proposed for operation of modular multilevel converters (MMCs in high voltage direct current (HVDC transmission systems. The proposed modulation function-based control technique is developed based on thorough and precise analyses of all MMC voltages and currents in the a-b-c reference frame in which the alternating current (AC-side voltage is the first target to be obtained. Using the AC-side voltage, the combination of the MMC upper and lower arm voltages is achieved as the main structure of the proposed modulation function. The main contribution of this paper is to obtain two very simple new modulation functions to control MMC performance in different operating conditions. The features of the modulation function-based control technique are as follows: (1 this control technique is very simple and can be easily achieved in a-b-c reference frame without the need of using Park transformation; and (2 in addition, the inherent properties of the MMC model are considered in the proposed control technique. Considering these properties leads to constructing a control technique that is robust against MMC parameters changes and also is a very good tracking method for the components of MMC input currents. These features lead to improving the operation of MMC significantly, which can act as a rectifier in the HVDC structure. The simulation studies are conducted through MATLAB/SIMULINK software, and the results obtained verify the effectiveness of the proposed modulation function-based control technique.

  15. Triphase Cascaded Converters with Direct Synchronous Pulswidth Modulation

    DEFF Research Database (Denmark)

    Oleschuk, V.; Blaabjerg, Frede; Bose, B. K.

    2002-01-01

    A novel method of direct synchronous pulse-width modulation (PWM) is applied for control of modular multilevel converters consisting from three standard triphase inverter modules along with an 0.33 p.u. output transformer. The proposed method provides synchronisation of the voltage waveforms...... for both each module and the composed voltage at the output of the converter. Multilevel output voltage of the converter has quarter-wave symmetry during the whole range including the zone of overmodulation. Both continuous and discontinuous versions of synchronous PWM, based on a vector approach...

  16. High-frequency autonomic modulation: a new model for analysis of autonomic cardiac control.

    Science.gov (United States)

    Champéroux, Pascal; Fesler, Pierre; Judé, Sebastien; Richard, Serge; Le Guennec, Jean-Yves; Thireau, Jérôme

    2018-05-03

    Increase in high-frequency beat-to-beat heart rate oscillations by torsadogenic hERG blockers appears to be associated with signs of parasympathetic and sympathetic co-activation which cannot be assessed directly using classic methods of heart rate variability analysis. The present work aimed to find a translational model that would allow this particular state of the autonomic control of heart rate to be assessed. High-frequency heart rate and heart period oscillations were analysed within discrete 10 s intervals in a cohort of 200 healthy human subjects. Results were compared to data collected in non-human primates and beagle dogs during pharmacological challenges and torsadogenic hERG blockers exposure, in 127 genotyped LQT1 patients on/off β-blocker treatment and in subgroups of smoking and non-smoking subjects. Three states of autonomic modulation, S1 (parasympathetic predominance) to S3 (reciprocal parasympathetic withdrawal/sympathetic activation), were differentiated to build a new model of heart rate variability referred to as high-frequency autonomic modulation. The S2 state corresponded to a specific state during which both parasympathetic and sympathetic systems were coexisting or co-activated. S2 oscillations were proportionally increased by torsadogenic hERG-blocking drugs, whereas smoking caused an increase in S3 oscillations. The combined analysis of the magnitude of high-frequency heart rate and high-frequency heart period oscillations allows a refined assessment of heart rate autonomic modulation applicable to long-term ECG recordings and offers new approaches to assessment of the risk of sudden death both in terms of underlying mechanisms and sensitivity. © 2018 The Authors. British Journal of Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.

  17. A Modified Multiband Hysteresis Controlled DTC of Induction Machine with 27-level asymmetrical CHB-MLI with NVC modulation

    Directory of Open Access Journals (Sweden)

    Rohith Balaji Jonnala

    2018-03-01

    Full Text Available The influence of Direct Torque Controlled Induction Motor Drive in the area of industrial application is very high; it presents foremost area of controllability of load at different states of operation. The major snags to the controller are maintaining Constant Switching Frequency and Infeasibility state. This paper concentrates on rectifying these problems with Modified Multiband Hysteresis Controller and Nearest Vector Control Modulated Asymmetrical Cascaded H-Bridge Multilevel Inverter for the better drive operation. In this case proper modification in MHC gives the optimal utilizations of each control vector to avoid the infeasibility states with a Lookup-Table and Multilevel Inverter gives more number of control voltage vectors with constant switching frequency for flexible operation of drive with low disturbances. Direct Torque Control equipped with these two modules achieves better operating conditions with low Torque ripples, low distorted flux and speed with different loads, and all other satisfactory load operating parameters.

  18. Bilobalide modulates serotonin-controlled behaviors in the nematode Caenorhabditis elegans

    Directory of Open Access Journals (Sweden)

    Luo Yuan

    2009-06-01

    Full Text Available Abstract Background Dysfunctions in the serotonergic system have been implicated in several neurological disorders such as depression. Elderly individuals who have been diagnosed with clinical depression show elevated cases of neurodegenerative diseases. This has led to suggestions that modulating the serotonin (5-HT system could provide an alternative method to current therapies for alleviating these pathologies. The neuroprotective effects of bilobalide in vitro have been documented. We aim to determine whether bilobalide affects the 5-HT system in the nematode C. elegans. The wild type worms, as well as well-characterized 5-HT mutants, were fed with bilobalide in a range of concentrations, and several 5-HT controlled behaviors were tested. Results We observed that bilobalide significantly inhibited 5-HT-controlled egg-laying behavior in a dose-dependent manner, which was blocked in the 5-HT receptor mutants (ser-4, mod-1, but not in the 5-HT transporter (mod-5 or synthesis (tph-1 mutants. Bilobalide also potentiated a 5-HT-controlled, experience-dependent locomotory behavior, termed the enhanced slowing response in the wild type animals. However, this effect was fully blocked in 5-HT receptor mod-1 and dopamine defective cat-2 mutants, but only partially blocked in ser-4 mutants. We also demonstrated that acetylcholine transmission was inhibited in a transgenic C. elegans strain that constitutively expresses Aβ, and bilobalide did not significantly affect this inhibition. Conclusion These results suggest that bilobalide may modulate specific 5-HT receptor subtypes, which involves interplay with dopamine transmission. Additional studies for the function of bilobalide in neurotransmitter systems could aid in our understanding of its neuroprotective properties.

  19. Relationship between width of greater trochanters and width of iliac wings in tronchanteric bursitis.

    Science.gov (United States)

    Viradia, Neal K; Berger, Alex A; Dahners, Laurence E

    2011-09-01

    Trochanteric bursitis is a common disorder that is characterized by inflammation of the bursa, superficial to the greater trochanter of the femur, leading to pain in the lateral hip, and often occurs because of acute trauma or repetitive friction involving the iliotibial band, the greater trochanter, and the bursa. In the study reported here, we hypothesized that the increased incidence of bursitis may be the result of the increased prominence of the trochanter in relation to the wings of the iliac crest. Distances between the outermost edges of trochanters and iliac wings were measured in 202 patients from the University of North Carolina Health Care System-101 without a known diagnosis and 101 with a clinical diagnosis of trochanteric bursitis. To determine significance, t tests for nonpaired data were used. Mean (SD) difference between trochanter and iliac wing widths was 28 (20) mm in the group diagnosed with trochanteric bursitis and 17 (18) mm in the control group. The difference between the groups in this regard was significant (Pbursitis group and 1.05 (.06) in the control group. The difference between these groups was significant (Pbursitis.

  20. Electronic module for control of sample feeding device of spectrometers of X-ray fluorescent analysis of CRV type

    International Nuclear Information System (INIS)

    Petrov, V.A.; Fursov, A.V.

    2002-01-01

    The scheme of electronic module for sample feeding device control for the CRV type X-ray fluorescence analysis spectrometers is considered. This module provides realization of next functions: sample change operations and installation in starting position; signaling and defense at emergency cases; indication of any sample amount in the spectrometer chamber; testing function at tuning and testing of modules. All these principal functions are entrusted with microcontroller. Programming of the microcontroller is putting into effect by algorithm of the whole sample feeding device. In the capacity of microcontroller the single crystalline processor PICI16C54 and stepping motor of NV-306-V2202 model have been used

  1. Antioxidant and signal modulation properties of plant polyphenols in controlling vascular inflammation.

    Science.gov (United States)

    Kostyuk, Vladimir A; Potapovich, Alla I; Suhan, Tatyana O; de Luca, Chiara; Korkina, Liudmila G

    2011-05-11

    Oxidized low-density lipoproteins (oxLDL) play a critical role in the initiation of atherosclerosis through activation of inflammatory signaling. In the present work we investigated the role of antioxidant and signal modulation properties of plant polyphenols in controlling vascular inflammation. Significant decrease in intracellular NO level and superoxide overproduction was found in human umbilical vein endothelial cells (HUVEC) treated with oxLDL, but not with LDL. The redox imbalance was prevented by the addition of quercetin or resveratrol. Expression analysis of 14 genes associated with oxidative stress and inflammation revealed oxLDL-mediated up-regulation of genes specifically involved in leukocyte recruitment and adhesion. This up-regulation could be partially avoided by the addition of verbascoside or resveratrol, while treatment with quercetin resulted in a further increase in the expression of these genes. Lipopolysaccharide (LPS)-treated HUVEC were also used for the evaluation of anti-inflammatory potency of plant polyphenols. Significant differences between HUVEC treaded with oxLDL and LPS were found in both the expression pattern of inflammation-related genes and the effects of plant polyphenols on cellular responses. The present data indicate that plant polyphenols may affect vascular inflammation not only as antioxidants but also as modulators of inflammatory redox signaling pathways. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

  2. Ghrelin potentiates cardiac reactivity to stress by modulating sympathetic control and beta-adrenergic response.

    Science.gov (United States)

    Camargo-Silva, Gabriel; Turones, Larissa Córdova; da Cruz, Kellen Rosa; Gomes, Karina Pereira; Mendonça, Michelle Mendanha; Nunes, Allancer; de Jesus, Itamar Guedes; Colugnati, Diego Basile; Pansani, Aline Priscila; Pobbe, Roger Luis Henschel; Santos, Robson; Fontes, Marco Antônio Peliky; Guatimosim, Silvia; de Castro, Carlos Henrique; Ianzer, Danielle; Ferreira, Reginaldo Nassar; Xavier, Carlos Henrique

    2018-03-01

    Prior evidence indicates that ghrelin is involved in the integration of cardiovascular functions and behavioral responses. Ghrelin actions are mediated by the growth hormone secretagogue receptor subtype 1a (GHS-R1a), which is expressed in peripheral tissues and central areas involved in the control of cardiovascular responses to stress. In the present study, we assessed the role of ghrelin - GHS-R1a axis in the cardiovascular reactivity to acute emotional stress in rats. Ghrelin potentiated the tachycardia evoked by restraint and air jet stresses, which was reverted by GHS-R1a blockade. Evaluation of the autonomic balance revealed that the sympathetic branch modulates the ghrelin-evoked positive chronotropy. In isolated hearts, the perfusion with ghrelin potentiated the contractile responses caused by stimulation of the beta-adrenergic receptor, without altering the amplitude of the responses evoked by acetylcholine. Experiments in isolated cardiomyocytes revealed that ghrelin amplified the increases in calcium transient changes evoked by isoproterenol. Taken together, our results indicate that the Ghrelin-GHS-R1a axis potentiates the magnitude of stress-evoked tachycardia by modulating the autonomic nervous system and peripheral mechanisms, strongly relying on the activation of cardiac calcium transient and beta-adrenergic receptors. Copyright © 2018 Elsevier Inc. All rights reserved.

  3. Ribosomal protein S6 phosphorylation is controlled by TOR and modulated by PKA in Candida albicans.

    Science.gov (United States)

    Chowdhury, Tahmeena; Köhler, Julia R

    2015-10-01

    TOR and PKA signaling pathways control eukaryotic cell growth and proliferation. TOR activity in model fungi, such as Saccharomyces cerevisiae, responds principally to nutrients, e.g., nitrogen and phosphate sources, which are incorporated into the growing cell mass; PKA signaling responds to the availability of the cells' major energy source, glucose. In the fungal commensal and pathogen, Candida albicans, little is known of how these pathways interact. Here, the signal from phosphorylated ribosomal protein S6 (P-S6) was defined as a surrogate marker for TOR-dependent anabolic activity in C. albicans. Nutritional, pharmacologic and genetic modulation of TOR activity elicited corresponding changes in P-S6 levels. The P-S6 signal corresponded to translational activity of a GFP reporter protein. Contributions of four PKA pathway components to anabolic activation were then examined. In high glucose concentrations, only Tpk2 was required to upregulate P-S6 to physiologic levels, whereas all four tested components were required to downregulate P-S6 in low glucose. TOR was epistatic to PKA components with respect to P-S6. In many host niches inhabited by C. albicans, glucose is scarce, with protein being available as a nitrogen source. We speculate that PKA may modulate TOR-dependent cell growth to a rate sustainable by available energy sources, when monomers of anabolic processes, such as amino acids, are abundant. © 2015 John Wiley & Sons Ltd.

  4. The tongue and its control by sleep state-dependent modulators.

    Science.gov (United States)

    Horner, R L

    2011-12-01

    The neural networks controlling vital functions such as breathing are embedded in the brain, the neural and chemical environment of which changes with state, i.e., wakefulness, non-rapid eye movement (non-REM) sleep and REM sleep, and with commonly administered drugs such as anaesthetics, sedatives and ethanol. One particular output from the state-dependent chemical brain is the focus of attention in this paper; the motor output to the muscles of the tongue, specifically the actions of state-dependent modulators acting at the hypoglossal motor pool. Determining the mechanisms underlying the modulation of the hypoglossal motor output during sleep is relevant to understanding the spectrum of increased upper airway resistance, airflow limitation, hypoventilation and airway obstructions that occur during natural and drug-influenced sleep in humans. Understanding the mechanisms underlying upper airway dysfunction in sleep-disordered breathing is also important given the large and growing prevalence of obstructive sleep apnea syndrome which constitutes a major public health problem with serious clinical, social and economic consequences.

  5. Stroop proactive control and task conflict are modulated by concurrent working memory load.

    Science.gov (United States)

    Kalanthroff, Eyal; Avnit, Amir; Henik, Avishai; Davelaar, Eddy J; Usher, Marius

    2015-06-01

    Performance on the Stroop task reflects two types of conflict-informational (between the incongruent word and font color) and task (between the contextually relevant color-naming task and the irrelevant, but automatic, word-reading task). According to the dual mechanisms of control theory (DMC; Braver, 2012), variability in Stroop performance can result from variability in the deployment of a proactive task-demand control mechanism. Previous research has shown that when proactive control (PC) is diminished, both increased Stroop interference and a reversed Stroop facilitation (RF) are observed. Although the current DMC model accounts for the former effect, it does not predict the observed RF, which is considered to be behavioral evidence for task conflict in the Stroop task. Here we expanded the DMC model to account for Stroop RF. Assuming that a concurrent working memory (WM) task reduces PC, we predicted both increased interference and an RF. Nineteen participants performed a standard Stroop task combined with a concurrent n-back task, which was aimed at reducing available WM resources, and thus overloading PC. Although the results indicated common Stroop interference and facilitation in the low-load condition (zero-back), in the high-load condition (two-back), both increased Stroop interference and RF were observed, consistent with the model's prediction. These findings indicate that PC is modulated by concurrent WM load and serves as a common control mechanism for both informational and task Stroop conflicts.

  6. Development of a quality control system in intensity modulated radiotherapy (IMRT)

    International Nuclear Information System (INIS)

    Souza, Roberto Salomon de; Braz, Delson

    2013-01-01

    The more complex the technique of radiotherapy is, the more refined the quality control must be. The technique of Intensity Modulated Radiotherapy (IMRT) is one of the technological innovations that gained space in the whole worlds in the last decade whose parameters of quality control are not fully established yet. The present work developed a phantom for quality control in IMRT to be implemented in the routine of the Radiotherapy Quality Control Program (PQRT) of the Brazilian National Cancer Institute (INCa). The device consists of a block formed by several polystyrene slice with TDLs and radiochromic film inserted. It should be sent (or taken) to the Program participating institutions to be irradiated under certain conditions and then be returned to the PQRT., where the discrepancy degree between the planned treatment and those effectively delivered will be evaluated. The system was validated through the test cases and the pilot program preformed in nine radiotherapy centers that perform IMRT in the southeast region of Brazil. (author)

  7. Generation of ozone by Ns-width pulsed power

    International Nuclear Information System (INIS)

    Shimomura, Naoyuki; Wakimoto, Masaya; Shinke, Yosuke; Nagata, Masayoshi; Namihira, Takao; Akiyama, Hidenori

    2002-01-01

    The demand of ozone will be increasing for wholesome and environment-conscious sterilizations. The generation of ozone using the pulsed power discharge will apply electron accelerations around the head of streamer discharge principally. The breakdown in reactor often limits the efficient generation. Therefore, the pulse shape should be controlled for dimension of the reactor. It is clear that a pulse shortening is one of effective approaches. Pulsed power voltage with ns-width applies for ozone generation. The effects, on concentration and efficiency of generation, of pulse shape, repetition rate of pulse, flow rate of oxygen gas, and dimension and configuration of reactor, are discussed. The dimension and configuration of the reactor are optimized for the pulse width

  8. Interface Control Document for the EMPACT Module that Estimates Electric Power Transmission System Response to EMP-Caused Damage

    Energy Technology Data Exchange (ETDEWEB)

    Werley, Kenneth Alan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mccown, Andrew William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)ory

    2016-06-26

    The EPREP code is designed to evaluate the effects of an Electro-Magnetic Pulse (EMP) on the electric power transmission system. The EPREP code embodies an umbrella framework that allows a user to set up analysis conditions and to examine analysis results. The code links to three major physics/engineering modules. The first module describes the EM wave in space and time. The second module evaluates the damage caused by the wave on specific electric power (EP) transmission system components. The third module evaluates the consequence of the damaged network on its (reduced) ability to provide electric power to meet demand. This third module is the focus of the present paper. The EMPACT code serves as the third module. The EMPACT name denotes EMP effects on Alternating Current Transmission systems. The EMPACT algorithms compute electric power transmission network flow solutions under severely damaged network conditions. Initial solutions are often characterized by unacceptible network conditions including line overloads and bad voltages. The EMPACT code contains algorithms to adjust optimally network parameters to eliminate network problems while minimizing outages. System adjustments include automatically adjusting control equipment (generator V control, variable transformers, and variable shunts), as well as non-automatic control of generator power settings and minimal load shedding. The goal is to evaluate the minimal loss of customer load under equilibrium (steady-state) conditions during peak demand.

  9. Cell intrinsic modulation of Wnt signaling controls neuroblast migration in C. elegans.

    Science.gov (United States)

    Mentink, Remco A; Middelkoop, Teije C; Rella, Lorenzo; Ji, Ni; Tang, Chung Yin; Betist, Marco C; van Oudenaarden, Alexander; Korswagen, Hendrik C

    2014-10-27

    Members of the Wnt family of secreted signaling proteins are key regulators of cell migration and axon guidance. In the nematode C. elegans, the migration of the QR neuroblast descendants requires multiple Wnt ligands and receptors. We found that the migration of the QR descendants is divided into three sequential phases that are each mediated by a distinct Wnt signaling mechanism. Importantly, the transition from the first to the second phase, which is the main determinant of the final position of the QR descendants along the anteroposterior body axis, is mediated through a cell-autonomous process in which the time-dependent expression of a Wnt receptor turns on the canonical Wnt/β-catenin signaling response that is required to terminate long-range anterior migration. Our results show that, in addition to direct guidance of cell migration by Wnt morphogenic gradients, cell migration can also be controlled indirectly through cell-intrinsic modulation of Wnt signaling responses.

  10. A microcomputer-controlled modulation technique for the detection of transient species in UV photoelectron spectroscopy

    International Nuclear Information System (INIS)

    Lonkhuyzen, H. van; Muller, H.G.; Lange, C.A. de

    1980-01-01

    A microcomputer-controlled modulation method is described to measure UV photoelectron spectra of transient species generated in a microwave discharge. Spectra at low and high microwave power levels are simultaneously recorded and afterwards linearly combined in order to remove parent compound signals. The method is applied to discharged oxygen where the transition O 2 + ( 2 PHIsub(u)) 2 ( 1 Δsub(g)) becomes visible without interference from the parent molecule O 2 ( 3 Σsub(g) - ), and to discharged sulphur dioxide where SO( 3 Σ - ) and S( 3 P) photoelectron spectra are obtained free from SO 2 bands. Finally the build-up of transient bands as a function of time is recorded. (orig.)

  11. Control of lignin solubility and particle formation modulates its antioxidant efficiency in lipid medium

    DEFF Research Database (Denmark)

    Barsberg, Søren Talbro; Thygesen, Lisbeth Garbrecht; Sanadi, Anand Ramesh

    2014-01-01

    Lignin is an abundant plant polymer usually regarded as waste material. In the present work, antioxidant properties of lignin preparations with differing lipid solubility were studied using biodiesel as a convenient lipid test substrate. In place of formerly used assays, we used attenuated total...... reflectance (ATR) FT-IR spectroscopy to follow in situ biodiesel autoxidation on a heated ATR crystal as a function of time. The study demonstrates that a complex balance between intrinsic (chemical) efficiency, solubility, and particle formation controls the antioxidant efficiency of differently prepared...... lignin fractions. It was found that solubility and particle formation of lignin preparations strongly modulate its antioxidant efficiency and that these properties might depend on the presence of lipid components within the original lignin source....

  12. On delta-modulated control: A simple system with complex dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Xia Xiaohua [Department of Electrical, Electronic and Computer Engineering, University of Pretoria, Pretoria 0002 (South Africa)]. E-mail: xxia@postino.up.ac.za; Chen Guanrong [Department of Electronic Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong (China)]. E-mail: gchen@ee.cityu.edu.hk

    2007-08-15

    In this paper, we investigate some interesting properties of a scalar system controlled by {delta}-modulated feedback. We show that there are three different cases. In the first case, there is a minimal global attractor which consists of only two points. The two points form either one 2-periodic orbit or two 1-periodic orbits (fixed points). We also characterize the attracting region for each of these two points. In the second case, the maximal stabilizable region is bounded, and there is a minimal local attractor inside this stabilizable region. In the third case, the maximal stabilizable set is a Cantor set, which is a repeller of the system, and the system is chaotic on the Cantor set.

  13. Presynaptic Ionotropic Receptors Controlling and Modulating the Rules for Spike Timing-Dependent Plasticity

    Directory of Open Access Journals (Sweden)

    Matthijs B. Verhoog

    2011-01-01

    Full Text Available Throughout life, activity-dependent changes in neuronal connection strength enable the brain to refine neural circuits and learn based on experience. In line with predictions made by Hebb, synapse strength can be modified depending on the millisecond timing of action potential firing (STDP. The sign of synaptic plasticity depends on the spike order of presynaptic and postsynaptic neurons. Ionotropic neurotransmitter receptors, such as NMDA receptors and nicotinic acetylcholine receptors, are intimately involved in setting the rules for synaptic strengthening and weakening. In addition, timing rules for STDP within synapses are not fixed. They can be altered by activation of ionotropic receptors located at, or close to, synapses. Here, we will highlight studies that uncovered how network actions control and modulate timing rules for STDP by activating presynaptic ionotropic receptors. Furthermore, we will discuss how interaction between different types of ionotropic receptors may create “timing” windows during which particular timing rules lead to synaptic changes.

  14. Nuclear Technology. Course 28: Welding Inspection. Module 28-6, Process Controls.

    Science.gov (United States)

    Espy, John

    This sixth in a series of ten modules for a course titled Welding Inspection describes procedures review, process monitoring, and weld defect analysis. The module follows a typical format that includes the following sections: (1) introduction, (2) module prerequisites, (3) objectives, (4) notes to instructor/student, (5) subject matter, (6)…

  15. Narrow widths of old and new resonances

    International Nuclear Information System (INIS)

    Pasupathy, J.

    1977-01-01

    A quantitative measure of the suppression factors involved in the pionic decays of mesons phi(1019) and f'(1514) as compared to their kaonic psi(3100) and psi(3700) decays are explained using the two different approaches, viz., the phenomenological S matrix approach and the field theoretical approach. The importance of the O-Z-I rule is brought out. The partial width GAMMA(phi → 3π) has been calculated using the dual model for the scattering kappa kappa(bar) → rhoπ. The effective coupling psi rho π is evaluated. The partial widths for psi → e + e - and psi → hadrons is calculated on a field theoretical approach. In conclusion, it appears that there are no serious objections to interpreting psi and psi' as cc - states. Most of their properties can be understood in a qualitative and in semi-quantitative way. (A.K.)

  16. Numerical simulation of distorted crystal Darwin width

    International Nuclear Information System (INIS)

    Wang Li; Xu Zhongmin; Wang Naxiu

    2012-01-01

    A new numerical simulation method according to distorted crystal optical theory was used to predict the direct-cooling crystal monochromator optical properties(crystal Darwin width) in this study. The finite element analysis software was used to calculate the deformed displacements of DCM crystal and to get the local reciprocal lattice vector of distorted crystal. The broadening of direct-cooling crystal Darwin width in meridional direction was estimated at 4.12 μrad. The result agrees well with the experimental data of 5 μrad, while it was 3.89 μrad by traditional calculation method of root mean square (RMS) of the slope error in the center line of footprint. The new method provides important theoretical support for designing and processing of monochromator crystal for synchrotron radiation beamline. (authors)

  17. Exotic meson decay widths using lattice QCD

    International Nuclear Information System (INIS)

    Cook, M. S.; Fiebig, H. R.

    2006-01-01

    A decay width calculation for a hybrid exotic meson h, with J PC =1 -+ , is presented for the channel h→πa 1 . This quenched lattice QCD simulation employs Luescher's finite box method. Operators coupling to the h and πa 1 states are used at various levels of smearing and fuzzing, and at four quark masses. Eigenvalues of the corresponding correlation matrices yield energy spectra that determine scattering phase shifts for a discrete set of relative πa 1 momenta. Although the phase shift data is sparse, fits to a Breit-Wigner model are attempted, resulting in a decay width of about 60 MeV when averaged over two lattice sizes having a lattice spacing of 0.07 fm

  18. Analysis of reduced widths and size

    International Nuclear Information System (INIS)

    Sharma, H.C.; Ram Raj; Nath, N.

    1977-01-01

    Recent data on S-wave neutron reduced widths for a large number of nuclei have been analysed nucleus-wise and the calculations for the degree of freedom of the associated (chi) 2 -distribution have been made using the Porter and Thomas procedure. It is noted that a number of nuclei can be fitted by a (chi) 2 -distribution with degree of freedom one, while there are few which are identified to follow a (chi) 2 -distribution with degree of freedom two and even more than two. The present analysis thus contradicts the usual presumption according to which the degree of freedom is taken to be always unity. An analytical attempt has also been made to ascertain the suitability of the data on reduced widths to be used for the analysis. These considerations are likely to modify the neutron cross-section evaluations. (author)

  19. Discrete/PWM Ballast-Resistor Controller

    Science.gov (United States)

    King, Roger J.

    1994-01-01

    Circuit offers low switching loss and automatic compensation for failure of ballast resistor. Discrete/PWM ballast-resistor controller improved shunt voltage-regulator circuit designed to supply power from high-resistance source to low-impedance bus. Provides both coarse discrete voltage levels (by switching of ballast resistors) and continuous fine control of voltage via pulse-width modulation.

  20. Direct modulation of T-box riboswitch-controlled transcription by protein synthesis inhibitors.

    Science.gov (United States)

    Stamatopoulou, Vassiliki; Apostolidi, Maria; Li, Shuang; Lamprinou, Katerina; Papakyriakou, Athanasios; Zhang, Jinwei; Stathopoulos, Constantinos

    2017-09-29

    Recently, it was discovered that exposure to mainstream antibiotics activate numerous bacterial riboregulators that control antibiotic resistance genes including metabolite-binding riboswitches and other transcription attenuators. However, the effects of commonly used antibiotics, many of which exhibit RNA-binding properties, on the widespread T-box riboswitches, remain unknown. In Staphylococcus aureus, a species-specific glyS T-box controls the supply of glycine for both ribosomal translation and cell wall synthesis, making it a promising target for next-generation antimicrobials. Here, we report that specific protein synthesis inhibitors could either significantly increase T-box-mediated transcription antitermination, while other compounds could suppress it, both in vitro and in vivo. In-line probing of the full-length T-box combined with molecular modelling and docking analyses suggest that the antibiotics that promote transcription antitermination stabilize the T-box:tRNA complex through binding specific positions on stem I and the Staphylococcal-specific stem Sa. By contrast, the antibiotics that attenuate T-box transcription bind to other positions on stem I and do not interact with stem Sa. Taken together, our results reveal that the transcription of essential genes controlled by T-box riboswitches can be directly modulated by commonly used protein synthesis inhibitors. These findings accentuate the regulatory complexities of bacterial response to antimicrobials that involve multiple riboregulators. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  1. Autonomic Modulation in Duchenne Muscular Dystrophy during a Computer Task: A Prospective Control Trial.

    Directory of Open Access Journals (Sweden)

    Mayra Priscila Boscolo Alvarez

    Full Text Available Duchenne Muscular Dystrophy (DMD is characterized by progressive muscle weakness that can lead to disability. Owing to functional difficulties faced by individuals with DMD, the use of assistive technology is essential to provide or facilitate functional abilities. In DMD, cardiac autonomic dysfunction has been reported in addition to musculoskeletal impairment. Consequently, the objective was to investigate acute cardiac autonomic responses, by Heart Rate Variability (HRV, during computer tasks in subjects with DMD.HRV was assessed by linear and nonlinear methods, using the heart rate monitor Polar RS800CX chest strap Electrocardiographic measuring device. Then, 45 subjects were included in the group with DMD and 45 in the healthy Typical Development (TD control group. They were assessed for twenty minutes at rest sitting, and five minutes after undergoing a task on the computer.Individuals with DMD had a statistically significant lower parasympathetic cardiac modulation at rest when compared to the control group, which further declined when undergoing the tasks on the computer.DMD patients presented decreased HRV and exhibited greater intensity of cardiac autonomic responses during computer tasks characterized by vagal withdrawal when compared to the healthy TD control subjects.

  2. TransDetect Identifies a New Regulatory Module Controlling Phosphate Accumulation.

    Science.gov (United States)

    Pal, Sikander; Kisko, Mushtak; Dubos, Christian; Lacombe, Benoit; Berthomieu, Pierre; Krouk, Gabriel; Rouached, Hatem

    2017-10-01

    Identifying transcription factor (TFs) cooperation controlling target gene expression is still an arduous challenge. The accuracy of current methods at genome scale significantly drops with the increase in number of genes, which limits their applicability to more complex genomes, like animals and plants. Here, we developed an algorithm, TransDetect, able to predict TF combinations controlling the expression level of a given gene. TransDetect was used to identify novel TF modules regulating the expression of Arabidopsis ( Arabidopsis thaliana ) phosphate transporter PHO1;H3 comprising MYB15, MYB84, bHLH35, and ICE1. These TFs were confirmed to interact between themselves and with the PHO1;H3 promoter. Phenotypic and genetic analyses of TF mutants enable the organization of these four TFs and PHO1;H3 in a new gene regulatory network controlling phosphate accumulation in zinc-dependent manner. This demonstrates the potential of TransDetect to extract directionality in nondynamic transcriptomes and to provide a blueprint to identify gene regulatory network involved in a given biological process. © 2017 American Society of Plant Biologists. All Rights Reserved.

  3. Meson widths from string worldsheet instantons

    International Nuclear Information System (INIS)

    Faulkner, Thomas; Liu, Hong

    2009-01-01

    We show that open strings living on a D-brane which lies outside an AdS black hole can tunnel into the black hole through worldsheet instantons. These instantons have a simple interpretation in terms of thermal quarks in the dual Yang-Mills (YM) theory. As an application we calculate the width of a meson in a strongly coupled quark-gluon plasma which is described holographically as a massless mode on a D7 brane in AdS 5 xS 5 . While the width of the meson is zero to all orders in the 1/√(λ) expansion with λ the 't Hooft coupling, it receives non-perturbative contributions in 1/√(λ) from worldsheet instantons. We find that the width increases quadratically with momentum at large momentum and comment on potential phenomenological implications of this enhancement for heavy ion collisions. We also comment on how this non-perturbative effect has important consequences for the phase structure of the YM theory obtained in the classical gravity limit

  4. Thermal Equilibrium Dynamic Control Based on DPWM Dual-Mode Modulation of High Power NPC Three-Level Inverter

    Directory of Open Access Journals (Sweden)

    Shi-Zhou Xu

    2016-01-01

    Full Text Available In some special applications of NPC three-level inverters, such as mine hoist, there exist special conditions of overloading during the whole hoisting process and large overload in starting stage, during which the power-loss calculation of power devices and thermal control are important factors affecting the thermal stability of inverters. The principles of SVPWM and DPWM were described in this paper firstly, based on which the dynamic power losses of the two modulations of hoist in single period were calculated. Secondly, a thermal equilibrium dynamic control based on DPMW dual-mode modulation was proposed, which can switch the modulation dynamically according to the change of dynamic power loss to realize dynamic control of power loss and thermal equilibrium of inverter. Finally, simulation and experiment prove the effectiveness of the proposed strategy.

  5. Width and partial widths of unstable particles in the light of the Nielsen identities

    International Nuclear Information System (INIS)

    Grassi, P.A.; Sirlin, A.; Kniehl, B.A.; Hamburg Univ.

    2001-09-01

    Fundamental properties of unstable particles, including mass, width, and partial widths, are examined on the basis of the Nielsen identities (NI) that describe the gauge dependence of Green functions. In particular, we prove that the pole residues and associated definitions of branching ratios and partial widths are gauge independent to all orders. A simpler, previously discussed definition of branching ratios and partial widths is found to be gauge independent through next-to-next-to-leading order. It is then explained how it may be modified in order to extend the gauge independence to all orders. We also show that the physical scattering amplitude is the most general combination of self-energy, vertex, and box contributions that is gauge independent for arbitrary s, discuss the analytical properties of the NI functions, and exhibit explicitly their one-loop expressions in the Z-γ sector of the Standard Model. (orig.)

  6. Width and partial widths of unstable particles in the light of the Nielsen identities

    International Nuclear Information System (INIS)

    Grassi, Pietro A.; Kniehl, Bernd A.; Sirlin, Alberto

    2002-01-01

    Fundamental properties of unstable particles, including mass, width, and partial widths, are examined on the basis of the Nielsen identities (NI) that describe the gauge dependence of Green functions. In particular, we prove that the pole residues and associated definitions of branching ratios and partial widths are gauge independent to all orders. A simpler, previously discussed definition of branching ratios and partial widths is found to be gauge independent through next-to-next-to-leading order. It is then explained how it may be modified in order to extend the gauge independence to all orders. We also show that the physical scattering amplitude is the most general combination of self-energy, vertex, and box contributions that is gauge independent for arbitrary s, discuss the analytical properties of the NI functions, and exhibit explicitly their one-loop expressions in the Z-γ sector of the standard model

  7. Vascular smooth muscle modulates endothelial control of vasoreactivity via reactive oxygen species production through myoendothelial communications.

    Directory of Open Access Journals (Sweden)

    Marie Billaud

    Full Text Available BACKGROUND: Endothelial control of vascular smooth muscle plays a major role in the resulting vasoreactivity implicated in physiological or pathological circulatory processes. However, a comprehensive understanding of endothelial (EC/smooth muscle cells (SMC crosstalk is far from complete. Here, we have examined the role of gap junctions and reactive oxygen species (ROS in this crosstalk and we demonstrate an active contribution of SMC to endothelial control of vasomotor tone. METHODOLOGY/PRINCIPAL FINDINGS: In small intrapulmonary arteries, quantitative RT-PCR, Western Blot analyses and immunofluorescent labeling evidenced connexin (Cx 37, 40 and 43 in EC and/or SMC. Functional experiments showed that the Cx-mimetic peptide targeted against Cx 37 and Cx 43 ((37,43Gap27 (1 reduced contractile and calcium responses to serotonin (5-HT simultaneously recorded in pulmonary arteries and (2 abolished the diffusion in SMC of carboxyfluorescein-AM loaded in EC. Similarly, contractile and calcium responses to 5-HT were decreased by superoxide dismutase and catalase which, catabolise superoxide anion and H(2O(2, respectively. Both Cx- and ROS-mediated effects on the responses to 5-HT were reversed by L-NAME, a NO synthase inhibitor or endothelium removal. Electronic paramagnetic resonance directly demonstrated that 5-HT-induced superoxide anion production originated from the SMC. Finally, whereas 5-HT increased NO production, it also decreased cyclic GMP content in isolated intact arteries. CONCLUSIONS/SIGNIFICANCE: These data demonstrate that agonist-induced ROS production in SMC targeting EC via myoendothelial gap junctions reduces endothelial NO-dependent control of pulmonary vasoreactivity. Such SMC modulation of endothelial control may represent a signaling pathway controlling vasoreactivity under not only physiological but also pathological conditions that often implicate excessive ROS production.

  8. Guanfacine modulates the emotional biasing of amygdala-prefrontal connectivity for cognitive control.

    Science.gov (United States)

    Schulz, Kurt P; Clerkin, Suzanne M; Newcorn, Jeffrey H; Halperin, Jeffrey M; Fan, Jin

    2014-09-01

    Functional interactions between amygdala and prefrontal cortex provide a cortical entry point for emotional cues to bias cognitive control. Stimulation of α2 adrenoceptors enhances the prefrontal control functions and blocks the amygdala-dependent encoding of emotional cues. However, the impact of this stimulation on amygdala-prefrontal interactions and the emotional biasing of cognitive control have not been established. We tested the effect of the α2 adrenoceptor agonist guanfacine on psychophysiological interactions of amygdala with prefrontal cortex for the emotional biasing of response execution and inhibition. Fifteen healthy adults were scanned twice with event-related functional magnetic resonance imaging while performing an emotional go/no-go task following administration of oral guanfacine (1mg) and placebo in a double-blind, counterbalanced design. Happy, sad, and neutral faces served as trial cues. Guanfacine moderated the effect of face emotion on the task-related functional connectivity of left and right amygdala with left inferior frontal gyrus compared to placebo, by selectively reversing the functional co-activation of the two regions for response execution cued by sad faces. This shift from positively to negatively correlated activation for guanfacine was associated with selective improvements in the relatively low accuracy of responses to sad faces seen for placebo. These results demonstrate the importance of functional interactions between amygdala and inferior frontal gyrus to both bottom-up biasing of cognitive control and top-down control of emotional processing, as well as for the α2 adrenoceptor-mediated modulation of these processes. These mechanisms offer a possibile method to address the emotional reactivity that is common to several psychiatric disorders. Copyright © 2014 Elsevier B.V. and ECNP. All rights reserved.

  9. Anticipatory modulation of digit placement for grasp control is affected by Parkinson's disease.

    Directory of Open Access Journals (Sweden)

    Jamie R Lukos

    2010-02-01

    Full Text Available Successful object manipulation relies on the ability to form and retrieve sensorimotor memories of digit forces and positions used in previous object lifts. Past studies of patients affected by Parkinson's disease (PD have revealed that the basal ganglia play a crucial role in the acquisition and/or retrieval of sensorimotor memories for grasp control. Whereas it is known that PD impairs anticipatory control of digit forces during grasp, learning deficits associated with the planning of digit placement have yet to be explored. This question is motivated by recent work in healthy subjects revealing that anticipatory control of digit placement plays a crucial role for successful manipulation.We asked ten PD patients off medication and ten age-matched controls to reach, grasp and lift an object whose center of mass (CM was on the left, right or center. The only task requirement was to minimize object roll during lift. The CM remained the same across consecutive trials (blocked condition or was altered from trial to trial (random condition. We hypothesized that impairment of the basal ganglia-thalamo-cortical circuits in PD patients would reduce their ability to anticipate digit placement appropriate to the CM location. Consequently, we predicted that PD patients would exhibit similar digit placement in the blocked vs. random conditions and produce larger peak object rolls than that of control subjects. In the blocked condition, PD patients exhibited significantly weaker modulation of fingertip contact points to CM location and larger object roll than controls (p<0.05 and p<0.01, respectively. Nevertheless, both controls and PD patients minimized object roll more in the blocked than in the random condition (p<0.01.Our findings indicate that, even though PD patients may have a residual ability of anticipatory control of digit contact points and forces, they fail to implement a motor plan with the same degree of effectiveness as controls. We conclude

  10. Chemically modified tetracyclines an emerging host modulator in chronic periodontitis patients: A randomized, double-blind, placebo-controlled, clinical trial.

    Science.gov (United States)

    Alyousef, Abdullah A; Divakar, Darshan Devang; Muzaheed

    2017-09-01

    Although periodontal diseases are caused by some of the specific pathogens, most of the tissue damage is caused by the host reaction to disease and not actually by the infections. Therefore, host modulatory therapy (HMT) has advanced benefit for the treatment of periodontitis, which works basically by reducing tissue destruction and regeneration in periodontium by altering the critical aspects of host response regulation and up regulating defensive regenerative responses. The present study was conducted with the goal to test an innovative therapeutic option using chemically modified tetracycline in patients affected with generalized, moderate and severe chronic periodontitis. We assumed that CMT might have the potential to provoke an assessable clinical result and pharmacologically impede the level inflammatory flow. CMT (incyclinide) treated group had significantly higher CAL (clinical attachment) values than Placebo Control suggesting an improved CAL in CMT treatment. Host modulation therapy width incyclinide can be as an adjunct to conventional nonsurgical therapies without antimicrobial resistance. Progress was noticed in the clinical parameters but not the serum CRP level in our study establishing the role of CMTs in controlling chronic periodontitis. Also CMT treatment indicates its role in anti-inflammatory process as it inhibited IL-12 and TNF alpha but IL-10 level was not affected. However, more randomized placebo-controlled clinical trials with large sample size are required in order to authenticate the usage of CMTs in chronic periodontitis treatment. Based on this understanding, exploration of the novel, low-cost synthetic inhibitors that can be used as potential therapeutic agents, has been tested. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Stark widths regularities within spectral series of sodium isoelectronic sequence

    Science.gov (United States)

    Trklja, Nora; Tapalaga, Irinel; Dojčinović, Ivan P.; Purić, Jagoš

    2018-02-01

    Stark widths within spectral series of sodium isoelectronic sequence have been studied. This is a unique approach that includes both neutrals and ions. Two levels of problem are considered: if the required atomic parameters are known, Stark widths can be calculated by some of the known methods (in present paper modified semiempirical formula has been used), but if there is a lack of parameters, regularities enable determination of Stark broadening data. In the framework of regularity research, Stark broadening dependence on environmental conditions and certain atomic parameters has been investigated. The aim of this work is to give a simple model, with minimum of required parameters, which can be used for calculation of Stark broadening data for any chosen transitions within sodium like emitters. Obtained relations were used for predictions of Stark widths for transitions that have not been measured or calculated yet. This system enables fast data processing by using of proposed theoretical model and it provides quality control and verification of obtained results.

  12. Balance (perceived and actual) and preferred stance width during pregnancy.

    Science.gov (United States)

    Jang, John; Hsiao, Katherine T; Hsiao-Wecksler, Elizabeth T

    2008-05-01

    Pregnant women often remark that their balance degrades during pregnancy; however, it appears that no studies have documented the gravida's perception of her balance nor measured direction-specific changes in balance throughout pregnancy or after delivery. Thirty women, fifteen pregnant and fifteen non-pregnant controls, were tested monthly and through 6-month postpartum. For each session, perceived degradation in sense of balance, laboratory-based balance measures, stance width, and the number of falls since the previous session were recorded. Laboratory-based balance measures, quantified by direction-specific measures of postural sway, were computed from ten 30s quiet-standing trials on a stationary force platform. Repeated-measures analysis of variance, paired t-tests, and Pearson correlations were use to examine group and time effects. For the pregnant group, perceived balance degradation and stance width were highly correlated (r = 0.94). Both increased during pregnancy (P r > 0.72) and also decreased significantly between the third trimester and postpartum (P pregnancy, but increased after delivery. Contrary to recent work suggesting fall rates of 25%, only 13% of our subjects (n = 2) fell during pregnancy. Perceived degradation in balance during pregnancy was strongly related to increasing postural sway instability in the anterior-posterior direction. Lateral stability was maintained during pregnancy and likely accomplished by increasing stance width.

  13. Modified model of neutron resonance widths distribution. Results of total gamma-widths approximation

    International Nuclear Information System (INIS)

    Sukhovoj, A.M.; Khitrov, V.A.

    2011-01-01

    Functional dependences of probability to observe given Γ n 0 value and algorithms for determination of the most probable magnitudes of the modified model of resonance parameter distributions were used for analysis of the experimental data on the total radiative widths of neutron resonances. As in the case of neutron widths, precise description of the Γ γ spectra requires a superposition of three and more probability distributions for squares of the random normally distributed values with different nonzero average and nonunit dispersion. This result confirms the preliminary conclusion obtained earlier at analysis of Γ n 0 that practically in all 56 tested sets of total gamma widths there are several groups noticeably differing from each other by the structure of their wave functions. In addition, it was determined that radiative widths are much more sensitive than the neutron ones to resonance wave functions structure. Analysis of early obtained neutron reduced widths distribution parameters for 157 resonance sets in the mass region of nuclei 35 ≤ A ≤ 249 was also performed. It was shown that the experimental values of widths can correspond with high probability to superposition of several expected independent distributions with their nonzero mean values and nonunit dispersion

  14. A bulk-controlled ring-VCO with 1/f-noise reduction for frequency ΔΣ modulator

    DEFF Research Database (Denmark)

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

    The paper introduces a bulk-controlled ring-VCO with a tail transistor utilizing flicker-noise (1/f-noise) reduction techniques for a frequency-based DeltaSigma modulator (FDSM). This VCO converts an analog input voltage to phase information under various bias conditions ranging from sub-threshol......The paper introduces a bulk-controlled ring-VCO with a tail transistor utilizing flicker-noise (1/f-noise) reduction techniques for a frequency-based DeltaSigma modulator (FDSM). This VCO converts an analog input voltage to phase information under various bias conditions ranging from sub...

  15. Intensity modulated radiation therapy: Analysis of patient specific quality control results, experience of Rene-Gauducheau Centre; Radiotherapie conformationnelle avec modulation d'intensite: analyse des resultats des controles precliniques, experience du centre Rene-Gauducheau

    Energy Technology Data Exchange (ETDEWEB)

    Chiavassa, S.; Brunet, G.; Gaudaire, S.; Munos-Llagostera, C.; Delpon, G.; Lisbona, A. [Service de physique medicale, centre Rene-Gauducheau, CLCC Nantes Atlantique, site hospitalier Nord, boulevard Jacques-Monod, 44805 Nantes Saint-Herblain cedex (France)

    2011-07-15

    Purpose. - Systematic verifications of patient's specific intensity-modulated radiation treatments are usually performed with absolute and relative measurements. The results constitute a database which allows the identification of potential systematic errors. Material and methods. - We analyzed 1270 beams distributed in 232 treatment plans. Step-and-shoot intensity-modulated radiation treatments were performed with a Clinac (6 and 23 MV) and sliding window intensity-modulated radiation treatments with a Novalis (6 MV). Results. - The distributions obtained do not show systematic error and all the control meet specified tolerances. Conclusion. - These results allow us to reduce controls specific patients for treatments performed under identical conditions (location, optimization and segmentation parameters of treatment planning system, etc.). (authors)

  16. Frequency-modulated laser ranging sensor with closed-loop control

    Science.gov (United States)

    Müller, Fabian M.; Böttger, Gunnar; Janeczka, Christian; Arndt-Staufenbiel, Norbert; Schröder, Henning; Schneider-Ramelow, Martin

    2018-02-01

    Advances in autonomous driving and robotics are creating high demand for inexpensive and mass-producible distance sensors. A laser ranging system (Lidar), based on the frequency-modulated continuous-wave (FMCW) method is built in this work. The benefits of an FMCW Lidar system are the low-cost components and the performance in comparison to conventional time-of-flight Lidar systems. The basic system consists of a DFB laser diode (λ= 1308 nm) and an asymmetric fiber-coupled Mach-Zehnder interferometer with a fixed delay line in one arm. Linear tuning of the laser optical frequency via injection current modulation creates a beat signal at the interferometer output. The frequency of the beat signal is proportional to the optical path difference in the interferometer. Since the laser frequency-to-current response is non-linear, a closed-loop feed-back system is designed to improve the tuning linearity, and consequently the measurement resolution. For fast active control, an embedded system with FPGA is used, resulting in a nearly linear frequency tuning, realizing a narrow peak in the Fourier spectrum of the beat signal. For free-space measurements, a setup with two distinct interferometers is built. The fully fiber-coupled Mach-Zehnder reference interferometer is part of the feed-back loop system, while the other - a Michelson interferometer - has a free-space arm with collimator lens and reflective target. A resolution of 2:0 mm for a 560 mm distance is achieved. The results for varying target distances show high consistency and a linear relation to the measured beat-frequency.

  17. Card9 mediates susceptibility to intestinal pathogens through microbiota modulation and control of bacterial virulence.

    Science.gov (United States)

    Lamas, Bruno; Michel, Marie-Laure; Waldschmitt, Nadine; Pham, Hang-Phuong; Zacharioudaki, Vassiliki; Dupraz, Louise; Delacre, Myriam; Natividad, Jane M; Costa, Gregory Da; Planchais, Julien; Sovran, Bruno; Bridonneau, Chantal; Six, Adrien; Langella, Philippe; Richard, Mathias L; Chamaillard, Mathias; Sokol, Harry

    2017-08-08

    In association with innate and adaptive immunity, the microbiota controls the colonisation resistance against intestinal pathogens. Caspase recruitment domain 9 ( CARD9 ), a key innate immunity gene, is required to shape a normal gut microbiota. Card9 -/- mice are more susceptible to the enteric mouse pathogen Citrobacter rodentium that mimics human infections with enteropathogenic and enterohaemorrhagic Escherichia coli . Here, we examined how CARD9 controls C. rodentium infection susceptibility through microbiota-dependent and microbiota-independent mechanisms. C. rodentium infection was assessed in conventional and germ-free (GF) wild-type (WT) and Card9 -/- mice. To explore the impact of Card9 -/- microbiota in infection susceptibility, GF WT mice were colonised with WT (WT→GF) or Card9 -/- ( Card9 -/- →GF) microbiota before C. rodentium infection. Microbiota composition was determined by 16S rDNA gene sequencing. Inflammation severity was determined by histology score and lipocalin level. Microbiota-host immune system interactions were assessed by quantitative PCR analysis. CARD9 controls pathogen virulence in a microbiota-independent manner by supporting a specific humoral response. Higher susceptibility to C. rodentium -induced colitis was observed in Card9 -/- →GF mice. The microbiota of Card9 -/- mice failed to outcompete the monosaccharide-consuming C. rodentium , worsening the infection severity. A polysaccharide-enriched diet counteracted the ecological advantage of C. rodentium and the defective pathogen-specific antibody response in Card9 -/- mice. CARD9 modulates the susceptibility to intestinal infection by controlling the pathogen virulence in a microbiota-dependent and microbiota-independent manner. Genetic susceptibility to intestinal pathogens can be overridden by diet intervention that restores humoural immunity and a competing microbiota. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017

  18. Modulations of the executive control network by stimulus onset asynchrony in a Stroop task

    Science.gov (United States)

    2013-01-01

    Background Manipulating task difficulty is a useful way of elucidating the functional recruitment of the brain’s executive control network. In a Stroop task, pre-exposing the irrelevant word using varying stimulus onset asynchronies (‘negative’ SOAs) modulates the amount of behavioural interference and facilitation, suggesting disparate mechanisms of cognitive processing in each SOA. The current study employed a Stroop task with three SOAs (−400, -200, 0 ms), using functional magnetic resonance imaging to investigate for the first time the neural effects of SOA manipulation. Of specific interest were 1) how SOA affects the neural representation of interference and facilitation; 2) response priming effects in negative SOAs; and 3) attentional effects of blocked SOA presentation. Results The results revealed three regions of the executive control network that were sensitive to SOA during Stroop interference; the 0 ms SOA elicited the greatest activation of these areas but experienced relatively smaller behavioural interference, suggesting that the enhanced recruitment led to more efficient conflict processing. Response priming effects were localized to the right inferior frontal gyrus, which is consistent with the idea that this region performed response inhibition in incongruent conditions to overcome the incorrectly-primed response, as well as more general action updating and response preparation. Finally, the right superior parietal lobe was sensitive to blocked SOA presentation and was most active for the 0 ms SOA, suggesting that this region is involved in attentional control. Conclusions SOA exerted both trial-specific and block-wide effects on executive processing, providing a unique paradigm for functional investigations of the cognitive control network. PMID:23902451

  19. Efficacy of Adolescent Suicide Prevention E-Learning Modules for Gatekeepers: A Randomized Controlled Trial.

    Science.gov (United States)

    Ghoncheh, Rezvan; Gould, Madelyn S; Twisk, Jos Wr; Kerkhof, Ad Jfm; Koot, Hans M

    2016-01-29

    Face-to-face gatekeeper training can be an effective strategy in the enhancement of gatekeepers' knowledge and self-efficacy in adolescent suicide prevention. However, barriers related to access (eg, time, resources) may hamper participation in face-to-face training sessions. The transition to a Web-based setting could address obstacles associated with face-to-face gatekeeper training. Although Web-based suicide prevention training targeting adolescents exists, so far no randomized controlled trials (RCTs) have been conducted to investigate their efficacy. This RCT study investigated the efficacy of a Web-based adolescent suicide prevention program entitled Mental Health Online, which aimed to improve the knowledge and self-confidence of gatekeepers working with adolescents (12-20 years old). The program consisted of 8 short e-learning modules each capturing an important aspect of the process of early recognition, guidance, and referral of suicidal adolescents, alongside additional information on the topic of (adolescent) suicide prevention. A total of 190 gatekeepers (ages 21 to 62 years) participated in this study and were randomized to either the experimental group or waitlist control group. The intervention was not masked. Participants from both groups completed 3 Web-based assessments (pretest, posttest, and 3-month follow-up). The outcome measures of this study were actual knowledge, and participants' ratings of perceived knowledge and perceived self-confidence using questionnaires developed specifically for this study. The actual knowledge, perceived knowledge, and perceived self-confidence of gatekeepers in the experimental group improved significantly compared to those in the waitlist control group at posttest, and the effects remained significant at 3-month follow-up. The overall effect sizes were 0.76, 1.20, and 1.02, respectively, across assessments. The findings of this study indicate that Web-based suicide prevention e-learning modules can be an

  20. MPK-1 ERK controls membrane organization in C. elegans oogenesis via a sex-determination module.

    Science.gov (United States)

    Arur, Swathi; Ohmachi, Mitsue; Berkseth, Matt; Nayak, Sudhir; Hansen, David; Zarkower, David; Schedl, Tim

    2011-05-17

    Tissues that generate specialized cell types in a production line must coordinate developmental mechanisms with physiological demand, although how this occurs is largely unknown. In the Caenorhabditis elegans hermaphrodite, the developmental sex-determination cascade specifies gamete sex in the distal germline, while physiological sperm signaling activates MPK-1/ERK in the proximal germline to control plasma membrane biogenesis and organization during oogenesis. We discovered repeated utilization of a self-contained negative regulatory module, consisting of NOS-3 translational repressor, FEM-CUL-2 (E3 ubiquitin ligase), and TRA-1 (Gli transcriptional repressor), which acts both in sex determination and in physiological demand control of oogenesis, coordinating these processes. In the distal germline, where MPK-1 is not activated, TRA-1 represses the male fate as NOS-3 functions in translational repression leading to inactivation of the FEM-CUL-2 ubiquitin ligase. In the proximal germline, sperm-dependent physiological MPK-1 activation results in phosphorylation-based inactivation of NOS-3, FEM-CUL-2-mediated degradation of TRA-1 and the promotion of membrane organization during oogenesis. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Trait susceptibility to worry modulates the effects of cognitive load on cognitive control: An ERP study.

    Science.gov (United States)

    Owens, Max; Derakshan, Nazanin; Richards, Anne

    2015-10-01

    According to the predictions of attentional control theory (ACT) of anxiety (Eysenck, Derakshan, Santos, & Calvo, 2007), worry is a central feature of anxiety that interferes with the ability to inhibit distracting information necessary for successful task performance. However, it is unclear how such cognitive control deficits are modulated by task demands and by the emotionality of the distractors. A sample of 31 participants (25 female) completed a novel flanker task with emotional and neutral distractors under low- and high-cognitive-load conditions. The negative-going N2 event-related potential was measured to index participants' level of top-down resource allocation in the inhibition of distractors under high- and low-load conditions. Results showed N2 amplitudes were larger under high- compared with low-load conditions. In addition, under high but not low load, trait worry was associated with greater N2 amplitudes. Our findings support ACT predictions that trait worry adversely affects goal-directed behavior, and is associated with greater recruitment of cognitive resources to inhibit the impact of distracting information under conditions in which cognitive resources are taxed. (c) 2015 APA, all rights reserved).

  2. Neural control and modulation of swimming speed in the larval zebrafish.

    Science.gov (United States)

    Severi, Kristen E; Portugues, Ruben; Marques, João C; O'Malley, Donald M; Orger, Michael B; Engert, Florian

    2014-08-06

    Vertebrate locomotion at different speeds is driven by descending excitatory connections to central pattern generators in the spinal cord. To investigate how these inputs determine locomotor kinematics, we used whole-field visual motion to drive zebrafish to swim at different speeds. Larvae match the stimulus speed by utilizing more locomotor events, or modifying kinematic parameters such as the duration and speed of swimming bouts, the tail-beat frequency, and the choice of gait. We used laser ablations, electrical stimulation, and activity recordings in descending neurons of the nucleus of the medial longitudinal fasciculus (nMLF) to dissect their contribution to controlling forward movement. We found that the activity of single identified neurons within the nMLF is correlated with locomotor kinematics, and modulates both the duration and oscillation frequency of tail movements. By identifying the contribution of individual supraspinal circuit elements to locomotion kinematics, we build a better understanding of how the brain controls movement. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. An HDAC3-PROX1 corepressor module acts on HNF4α to control hepatic triglycerides.

    Science.gov (United States)

    Armour, Sean M; Remsberg, Jarrett R; Damle, Manashree; Sidoli, Simone; Ho, Wesley Y; Li, Zhenghui; Garcia, Benjamin A; Lazar, Mitchell A

    2017-09-15

    The histone deacetylase HDAC3 is a critical mediator of hepatic lipid metabolism, and liver-specific deletion of HDAC3 leads to fatty liver. To elucidate the underlying mechanism, here we report a method of cross-linking followed by mass spectrometry to define a high-confidence HDAC3 interactome in vivo that includes the canonical NCoR-HDAC3 complex as well as Prospero-related homeobox 1 protein (PROX1). HDAC3 and PROX1 co-localize extensively on the mouse liver genome, and are co-recruited by hepatocyte nuclear factor 4α (HNF4α). The HDAC3-PROX1 module controls the expression of a gene program regulating lipid homeostasis, and hepatic-specific ablation of either component increases triglyceride content in liver. These findings underscore the importance of specific combinations of transcription factors and coregulators in the fine tuning of organismal metabolism.HDAC3 is a critical mediator of hepatic lipid metabolism and its loss leads to fatty liver. Here, the authors characterize the liver HDAC3 interactome in vivo, provide evidence that HDAC3 interacts with PROX1, and show that HDAC3 and PROX1 control expression of genes regulating lipid homeostasis.

  4. Controller for a High-Power, Brushless dc Motor

    Science.gov (United States)

    Fleming, David J.; Makdad, Terence A.

    1987-01-01

    Driving and braking torques controllable. Control circuit operates 7-kW, 45-lb-ft (61-N-m), three-phase, brushless dc motor in both motor and generator modes. In motor modes, energy from power source is pulse-width modulated to motor through modified "H-bridge" circuit, in generator mode, energy from motor is pulse-width modulated into bank of load resistors to provide variable braking torques. Circuit provides high-resolution torque control in both directions over wide range of speeds and torques. Tested successfully at bus voltages up to 200 Vdc and currents up to 45 A.

  5. Intensity modulated radiation therapy: Analysis of patient specific quality control results, experience of Rene-Gauducheau Centre

    International Nuclear Information System (INIS)

    Chiavassa, S.; Brunet, G.; Gaudaire, S.; Munos-Llagostera, C.; Delpon, G.; Lisbona, A.

    2011-01-01

    Purpose. - Systematic verifications of patient's specific intensity-modulated radiation treatments are usually performed with absolute and relative measurements. The results constitute a database which allows the identification of potential systematic errors. Material and methods. - We analyzed 1270 beams distributed in 232 treatment plans. Step-and-shoot intensity-modulated radiation treatments were performed with a Clinac (6 and 23 MV) and sliding window intensity-modulated radiation treatments with a Novalis (6 MV). Results. - The distributions obtained do not show systematic error and all the control meet specified tolerances. Conclusion. - These results allow us to reduce controls specific patients for treatments performed under identical conditions (location, optimization and segmentation parameters of treatment planning system, etc.). (authors)

  6. Method and apparatus for active control of combustion rate through modulation of heat transfer from the combustion chamber wall

    Science.gov (United States)

    Roberts, Jr., Charles E.; Chadwell, Christopher J.

    2004-09-21

    The flame propagation rate resulting from a combustion event in the combustion chamber of an internal combustion engine is controlled by modulation of the heat transfer from the combustion flame to the combustion chamber walls. In one embodiment, heat transfer from the combustion flame to the combustion chamber walls is mechanically modulated by a movable member that is inserted into, or withdrawn from, the combustion chamber thereby changing the shape of the combustion chamber and the combustion chamber wall surface area. In another embodiment, heat transfer from the combustion flame to the combustion chamber walls is modulated by cooling the surface of a portion of the combustion chamber wall that is in close proximity to the area of the combustion chamber where flame speed control is desired.

  7. Optically controlled reflection modulator using GaAs-AlGaAs n-i-p-i/multiple-quantum-well structures

    Science.gov (United States)

    Law, K.-K.; Simes, R. J.; Coldren, L. A.; Gossard, A. C.; Maserjian, J.

    1989-01-01

    An optically controlled reflection modulator has been demonstrated that consists of a combination of a GaAs-AlGaAs n-i-p-i doping structure with a multiple-quantum-well structures on top of a distributed Bragg reflector, all grown by MBE. A modulation of approximately 60 percent is obtained on the test structure, corresponding to a differential change of absorption coefficient in the quantum wells of approximately 7500/cm. Changes in reflectance can be observed with a control beam power as low as 1.5 microW. This device structure has the potential of being developed as an optically addressed spatial light modulator for optical information processing.

  8. Nuclear structure effects on alpha reduced widths

    International Nuclear Information System (INIS)

    Toth, K.S.; Ellis-Akovali, Y.A.; Kim, H.J.; McConnell, J.W.

    1987-01-01

    A review of α widths for s-wave transitions is presented together with a discussion of the following topics: (1) a new determination of the 218 Ra half-life and its relation to reflection asymmetry in nuclei near N = 130, (2) a measurement of the 194 Pb α-decay rate and the influence of the Z = 82 gap on neutron-deficient Pb nuclei, and (3) an up-date of α-decay-rate systematics for isotopes in the rare earth and medium-weight mass regions. 16 refs., 6 figs

  9. Statistical analysis of partial reduced width distributions

    International Nuclear Information System (INIS)

    Tran Quoc Thuong.

    1973-01-01

    The aim of this study was to develop rigorous methods for analysing experimental event distributions according to a law in chi 2 and to check if the number of degrees of freedom ν is compatible with the value 1 for the reduced neutron width distribution. Two statistical methods were used (the maximum-likelihood method and the method of moments); it was shown, in a few particular cases, that ν is compatible with 1. The difference between ν and 1, if it exists, should not exceed 3%. These results confirm the validity of the compound nucleus model [fr

  10. Simple method for calculating island widths

    International Nuclear Information System (INIS)

    Cary, J.R.; Hanson, J.D.; Carreras, B.A.; Lynch, V.E.

    1989-01-01

    A simple method for calculating magnetic island widths has been developed. This method uses only information obtained from integrating along the closed field line at the island center. Thus, this method is computationally less intensive than the usual method of producing surfaces of section of sufficient detail to locate and resolve the island separatrix. This method has been implemented numerically and used to analyze the buss work islands of ATF. In this case the method proves to be accurate to at least within 30%. 7 refs

  11. Resolving single bubble sonoluminescence flask width

    OpenAIRE

    Arakeri, Vijay H

    1998-01-01

    Single bubble sonoluminescence (SBSL), first studied and observed by Gaitan et al., is the of light emission from a single gas bubble trapped at the pressure maximum of a resonant sound field in a liquid medium, generally water. One of the most striking aspects of SBSL was the estimated optical flash width being less than 50 picoseconds (ps)3; this upper estimate was based on the relative response of a SBSL flash in comparison to a 34 ps laser pulse using a microchannel platephotomultiplier ...

  12. The optimal configuration of photovoltaic module arrays based on adaptive switching controls

    International Nuclear Information System (INIS)

    Chao, Kuei-Hsiang; Lai, Pei-Lun; Liao, Bo-Jyun

    2015-01-01

    Highlights: • We propose a strategy for determining the optimal configuration of a PV array. • The proposed strategy was based on particle swarm optimization (PSO) method. • It can identify the optimal module array connection scheme in the event of shading. • It can also find the optimal connection of a PV array even in module malfunctions. - Abstract: This study proposes a strategy for determining the optimal configuration of photovoltaic (PV) module arrays in shading or malfunction conditions. This strategy was based on particle swarm optimization (PSO). If shading or malfunctions of the photovoltaic module array occur, the module array immediately undergoes adaptive reconfiguration to increase the power output of the PV power generation system. First, the maximal power generated at various irradiation levels and temperatures was recorded during normal array operation. Subsequently, the irradiation level and module temperature, regardless of operating conditions, were used to recall the maximal power previously recorded. This previous maximum was compared with the maximal power value obtained using the maximum power point tracker to assess whether the PV module array was experiencing shading or malfunctions. After determining that the array was experiencing shading or malfunctions, PSO was used to identify the optimal module array connection scheme in abnormal conditions, and connection switches were used to implement optimal array reconfiguration. Finally, experiments were conducted to assess the strategy for identifying the optimal reconfiguration of a PV module array in the event of shading or malfunctions

  13. Post-error action control is neurobehaviorally modulated under conditions of constant speeded response

    Directory of Open Access Journals (Sweden)

    Takahiro eSoshi

    2015-01-01

    Full Text Available Post-error slowing is an error recovery strategy that contributes to action control, and occurs after errors in order to prevent future behavioral flaws. Error recovery often malfunctions in clinical populations, but the relationship between behavioral traits and recovery from error is unclear in healthy populations. The present study investigated the relationship between impulsivity and error recovery by simulating a speeded response situation using a Go/No-go paradigm that forced the participants to constantly make accelerated responses prior to stimuli disappearance (stimulus duration: 250 ms. Neural correlates of post-error processing were examined using event-related potentials (ERPs. Impulsivity traits were measured with self-report questionnaires (BIS-11, BIS/BAS. Behavioral results demonstrated that the commission error for No-go trials was 15%, but post-error slowing did not take place immediately. Delayed post-error slowing was negatively correlated with error rates and impulsivity traits, showing that response slowing was associated with reduced error rates and changed with impulsivity. Response-locked error ERPs were clearly observed for the error trials. Contrary to previous studies, error ERPs were not significantly related to post-error slowing. Stimulus-locked N2 was negatively correlated with post-error slowing and positively correlated with impulsivity traits at the second post-error Go trial: larger N2 activity was associated with greater post-error slowing and less impulsivity. In summary, under constant speeded conditions, error monitoring was dissociated from post-error action control, and post-error slowing did not occur quickly. Furthermore, post-error slowing and its neural correlate (N2 were modulated by impulsivity traits. These findings suggest that there may be clinical and practical efficacy of maintaining cognitive control of actions during error recovery under common daily environments that frequently evoke

  14. Post-error action control is neurobehaviorally modulated under conditions of constant speeded response.

    Science.gov (United States)

    Soshi, Takahiro; Ando, Kumiko; Noda, Takamasa; Nakazawa, Kanako; Tsumura, Hideki; Okada, Takayuki

    2014-01-01

    Post-error slowing (PES) is an error recovery strategy that contributes to action control, and occurs after errors in order to prevent future behavioral flaws. Error recovery often malfunctions in clinical populations, but the relationship between behavioral traits and recovery from error is unclear in healthy populations. The present study investigated the relationship between impulsivity and error recovery by simulating a speeded response situation using a Go/No-go paradigm that forced the participants to constantly make accelerated responses prior to stimuli disappearance (stimulus duration: 250 ms). Neural correlates of post-error processing were examined using event-related potentials (ERPs). Impulsivity traits were measured with self-report questionnaires (BIS-11, BIS/BAS). Behavioral results demonstrated that the commission error for No-go trials was 15%, but PES did not take place immediately. Delayed PES was negatively correlated with error rates and impulsivity traits, showing that response slowing was associated with reduced error rates and changed with impulsivity. Response-locked error ERPs were clearly observed for the error trials. Contrary to previous studies, error ERPs were not significantly related to PES. Stimulus-locked N2 was negatively correlated with PES and positively correlated with impulsivity traits at the second post-error Go trial: larger N2 activity was associated with greater PES and less impulsivity. In summary, under constant speeded conditions, error monitoring was dissociated from post-error action control, and PES did not occur quickly. Furthermore, PES and its neural correlate (N2) were modulated by impulsivity traits. These findings suggest that there may be clinical and practical efficacy of maintaining cognitive control of actions during error recovery under common daily environments that frequently evoke impulsive behaviors.

  15. Cortisol Modulation by Ayahuasca in Patients With Treatment Resistant Depression and Healthy Controls

    Directory of Open Access Journals (Sweden)

    Ana C. de Menezes Galvão

    2018-05-01

    Full Text Available Major depression is a highly prevalent mood disorder, affecting about 350 million people, and around 30% of the patients are resistant to currently available antidepressant medications. Recent evidence from a randomized controlled trial (RCT supports the rapid antidepressant effects of the psychedelic ayahuasca in treatment-resistant depression. The aim of this study was to explore the effect of ayahuasca on plasma cortisol and awakening salivary cortisol response, in the same group of treatment-resistant patients (MD and in healthy volunteers (C. Subjects received a single dose of ayahuasca or placebo (dosing session, and both plasma and awakening salivary cortisol response were measured at baseline (before dosing session and 48 h after the dosing session. Baseline assessment (D0 showed blunted awakening salivary cortisol response and hypocortisolemia in patients, with respect to healthy controls. Salivary cortisol was also measured during dosing session, and we observed higher increases for both C and MD that ingested ayahuasca than placebo. After 48 h from the dosing session with ayahuasca, patients' awakening salivary cortisol response is similar to the ones detected in controls. No significant changes in plasma cortisol levels were observed 48 h after the sessions. Therefore, these findings point to new evidence on the modulation of salivary cortisol levels as a result of an ayahuasca session, both in healthy and depressive volunteers. Considering that cortisol acts in regulation of distinct physiological pathways, emotional and cognitive processes, it is assumed to be critically involved to the etiology of depression and its regulation seems to be important for the treatment and remission of major depression, ayahuasca use as antidepressant should be further investigated. Moreover, this study highlights the importance of psychedelics in the treatment of human mental disorders.

  16. Low-bias flat band-stop filter based on velocity modulated gaussian graphene superlattice

    Science.gov (United States)

    Sattari-Esfahlan, S. M.; Shojaei, S.

    2018-05-01

    Transport properties of biased planar Gaussian graphene superlattice (PGGSL) with Fermi velocity barrier is investigated by transfer matrix method (TMM). It is observed that enlargement of bias voltage over miniband width breaks the miniband to WSLs leads to suppressing resonant tunneling. Transmission spectrum shows flat wide stop-band property controllable by external bias voltage with stop-band width of near 200 meV. The simulations demonstrate that strong velocity barriers prevent tunneling of Dirac electrons leading to controllable enhancement of stop-band width. By increasing ratio of Fermi velocity in barriers to wells υc stop-band width increase. As wide transmission stop-band width (BWT) of filter is tunable from 40 meV to 340 meV is obtained by enhancing ratio of υc from 0.2 to 1.5, respectively. Proposed structure suggests easy tunable wide band-stop electronic filter with a modulated flat stop-band characteristic by height of electrostatic barrier and structural parameters. Robust sensitivity of band width to velocity barrier intensity in certain bias voltages and flat band feature of proposed filter may be opens novel venue in GSL based flat band low noise filters and velocity modulation devices.

  17. Statistical process control applied to intensity modulated radiotherapy pretreatment controls with portal dosimetry;Maitrise statistique des processus appliquee aux controles avant traitement par dosimetrie portale en radiotherapie conformationnelle avec modulation d'intensite

    Energy Technology Data Exchange (ETDEWEB)

    Villani, N.; Noel, A. [Laboratoire de recherche en radiophysique, CRAN UMR 7039, Nancy universite-CNRS, 54 - Vandoeuvre-les-Nancy (France); Villani, N.; Gerard, K.; Marchesi, V.; Huger, S.; Noel, A. [Departement de radiophysique, centre Alexis-Vautrin, 54 - Vandoeuvre-les-Nancy (France); Francois, P. [Institut Curie, 75 - Paris (France)

    2010-06-15

    Purpose The first purpose of this study was to illustrate the contribution of statistical process control for a better security in intensity modulated radiotherapy (I.M.R.T.) treatments. This improvement is possible by controlling the dose delivery process, characterized by pretreatment quality control results. So, it is necessary to put under control portal dosimetry measurements (currently, the ionisation chamber measurements were already monitored by statistical process control thanks to statistical process control tools). The second objective was to state whether it is possible to substitute ionisation chamber with portal dosimetry in order to optimize time devoted to pretreatment quality control. Patients and methods At Alexis-Vautrin center, pretreatment quality controls in I.M.R.T. for prostate and head and neck treatments were performed for each beam of each patient. These controls were made with an ionisation chamber, which is the reference detector for the absolute dose measurement, and with portal dosimetry for the verification of dose distribution. Statistical process control is a statistical analysis method, coming from industry, used to control and improve the studied process quality. It uses graphic tools as control maps to follow-up process, warning the operator in case of failure, and quantitative tools to evaluate the process toward its ability to respect guidelines: this is the capability study. The study was performed on 450 head and neck beams and on 100 prostate beams. Results Control charts, showing drifts, both slow and weak, and also both strong and fast, of mean and standard deviation have been established and have shown special cause introduced (manual shift of the leaf gap of the multi-leaf collimator). Correlation between dose measured at one point, given with the E.P.I.D. and the ionisation chamber has been evaluated at more than 97% and disagreement cases between the two measurements were identified. Conclusion The study allowed to

  18. Modulation of Posterior Alpha Activity by Spatial Attention Allows for Controlling A Continuous Brain-Computer Interface

    NARCIS (Netherlands)

    Horschig, J.M.; Oosterheert, W.; Oostenveld, R.; Jensen, O.

    2015-01-01

    Here we report that the modulation of alpha activity by covert attention can be used as a control signal in an online brain-computer interface, that it is reliable, and that it is robust. Subjects were instructed to orient covert visual attention to the left or right hemifield. We decoded the

  19. A Brain Computer Interface for Robust Wheelchair Control Application Based on Pseudorandom Code Modulated Visual Evoked Potential

    DEFF Research Database (Denmark)

    Mohebbi, Ali; Engelsholm, Signe K.D.; Puthusserypady, Sadasivan

    2015-01-01

    In this pilot study, a novel and minimalistic Brain Computer Interface (BCI) based wheelchair control application was developed. The system was based on pseudorandom code modulated Visual Evoked Potentials (c-VEPs). The visual stimuli in the scheme were generated based on the Gold code...

  20. Control strategy for Single-phase Transformerless Three-leg Unified Power Quality Conditioner Based on Space Vector Modulation

    DEFF Research Database (Denmark)

    Lu, Yong; Xiao, Guochun; Wang, Xiongfei

    2016-01-01

    The unified power quality conditioner (UPQC) is known as an effective compensation device to improve PQ for sensitive end-users. This paper investigates the operation and control of a single-phase three-leg UPQC (TL-UPQC), where a novel space vector modulation method is proposed for naturally...

  1. Unravelling the role of quantum interference in the weak-field laser phase modulation control of photofragment distributions

    DEFF Research Database (Denmark)

    García-Vela, Alberto; Henriksen, Niels Engholm

    2016-01-01

    The role played by quantum interference in the laser phase modulation coherent control of photofragment distributions in the weak-field regime is investigated in detail in this work. The specific application involves realistic wave packet calculations of the transient vibrational populations of t...

  2. Isolated PDM and PWM DC-AC SICAMs[Pulse Density Modulated; Pulse Width Modulated

    Energy Technology Data Exchange (ETDEWEB)

    Ljusev, P.

    2004-03-15

    In this report a class of isolated PDM and PWM DC-AC SICAMs is described, which introduce the audio reference only in the output stage. AC-DC power supply is implemented in its simplest form: diode rectifier followed by a medium-size charge-storage capacitor. Isolation from the AC mains is achieved using a high frequency (HF) transformer, receiving the HF voltage pulses from the input 'inverter' stage and transferring them to the output 'rectifier+inverter' stage, which can use either PDM or PWM. The latter stage is then interfaced to the load using an output low-pass filter. Each of the dedicated stages is discussed in detail. Measurements on the master/slave PWM DC-AC SICAM prototype are presented to help benchmarking the performance of this class of SICAMs and identify the advantages and drawbacks. (au)

  3. Gener: a minimal programming module for chemical controllers based on DNA strand displacement.

    Science.gov (United States)

    Kahramanoğulları, Ozan; Cardelli, Luca

    2015-09-01

    : Gener is a development module for programming chemical controllers based on DNA strand displacement. Gener is developed with the aim of providing a simple interface that minimizes the opportunities for programming errors: Gener allows the user to test the computations of the DNA programs based on a simple two-domain strand displacement algebra, the minimal available so far. The tool allows the user to perform stepwise computations with respect to the rules of the algebra as well as exhaustive search of the computation space with different options for exploration and visualization. Gener can be used in combination with existing tools, and in particular, its programs can be exported to Microsoft Research's DSD tool as well as to LaTeX. Gener is available for download at the Cosbi website at http://www.cosbi.eu/research/prototypes/gener as a windows executable that can be run on Mac OS X and Linux by using Mono. ozan@cosbi.eu. © The Author 2015. Published by Oxford University Press.

  4. Dynamic and Progressive Control of DNA Origami Conformation by Modulating DNA Helicity with Chemical Adducts.

    Science.gov (United States)

    Chen, Haorong; Zhang, Hanyu; Pan, Jing; Cha, Tae-Gon; Li, Shiming; Andréasson, Joakim; Choi, Jong Hyun

    2016-05-24

    DNA origami has received enormous attention for its ability to program complex nanostructures with a few nanometer precision. Dynamic origami structures that change conformation in response to environmental cues or external signals hold great promises in sensing and actuation at the nanoscale. The reconfiguration mechanism of existing dynamic origami structures is mostly limited to single-stranded hinges and relies almost exclusively on DNA hybridization or strand displacement. Here, we show an alternative approach by demonstrating on-demand conformation changes with DNA-binding molecules, which intercalate between base pairs and unwind DNA double helices. The unwinding effect modulates the helicity mismatch in DNA origami, which significantly influences the internal stress and the global conformation of the origami structure. We demonstrate the switching of a polymerized origami nanoribbon between different twisting states and a well-constrained torsional deformation in a monomeric origami shaft. The structural transformation is shown to be reversible, and binding isotherms confirm the reconfiguration mechanism. This approach provides a rapid and reversible means to change DNA origami conformation, which can be used for dynamic and progressive control at the nanoscale.

  5. Statistical process control analysis for patient quality assurance of intensity modulated radiation therapy

    Science.gov (United States)

    Lee, Rena; Kim, Kyubo; Cho, Samju; Lim, Sangwook; Lee, Suk; Shim, Jang Bo; Huh, Hyun Do; Lee, Sang Hoon; Ahn, Sohyun

    2017-11-01

    This study applied statistical process control to set and verify the quality assurances (QA) tolerance standard for our hospital's characteristics with the criteria standards that are applied to all the treatment sites with this analysis. Gamma test factor of delivery quality assurances (DQA) was based on 3%/3 mm. Head and neck, breast, prostate cases of intensity modulated radiation therapy (IMRT) or volumetric arc radiation therapy (VMAT) were selected for the analysis of the QA treatment sites. The numbers of data used in the analysis were 73 and 68 for head and neck patients. Prostate and breast were 49 and 152 by MapCHECK and ArcCHECK respectively. C p value of head and neck and prostate QA were above 1.0, C pml is 1.53 and 1.71 respectively, which is close to the target value of 100%. C pml value of breast (IMRT) was 1.67, data values are close to the target value of 95%. But value of was 0.90, which means that the data values are widely distributed. C p and C pml of breast VMAT QA were respectively 1.07 and 2.10. This suggests that the VMAT QA has better process capability than the IMRT QA. Consequently, we should pay more attention to planning and QA before treatment for breast Radiotherapy.

  6. Design and dimensioning of pressfit connections in control modules; Betriebsfeste Bemessung von Steckverbindern in Steuergeraeten

    Energy Technology Data Exchange (ETDEWEB)

    Kimpel, Thomas; Jauernig, Udo [Robert Bosch GmbH, Schwieberdingen (Germany). Geschaeftsbereich Automotive Electronics; Becker, Rolf [Robert Bosch GmbH, Reutlingen (Germany); Wagener, Rainer [Fraunhofer-Institut fuer Betriebsfestigkeit und Systemzuverlaessigkeit (LBF), Darmstadt (Germany). Gruppe Bauteilgebundenes Werkstoffverhalten; Kaufmann, Heinz; Sonsino, Cetin Morris [Fraunhofer-Institut fuer Betriebsfestigkeit und Systemzuverlaessigkeit (LBF), Darmstadt (Germany)

    2013-07-01

    Pressfit technology as a cold contacting technology connects the printed circuit board to the external connection of the control module. The main function of the pressfit connection is the transportation of electrical signals and power. Depending on the construction the fixation of the printed circuit board can occur as a further function. The reliability requirements indicate that these functions are preserved over life time. A design model of the pressfit connection was developed for measuring the functions during cyclic mechanical loads. Furthermore, a suitable test bench was designed for applying the mechanical loads from production and operation. The failure mechanisms and resulting failures which occur under cyclic mechanical loads were acquired with the design model. The focal point was the contact zone because it is as the joint between the pressfit and the plated through hole a possible weak spot. It was shown that the electrical resistance of the contact zone could lead to a functional failure of the pressfit connection because of fretting corrosion in the gross slip mode. A correlation between the mechanical load capacity of the contact zone and the electrical resistance was established. For this, the multi physical functions of the joint were used with the objective to avoid fretting corrosion in gross slip mode during lifetime. A suitable test method to detect the load capacity in three dimensions was developed. (orig.)

  7. Glucose-ABL1-TOR Signaling Modulates Cell Cycle Tuning to Control Terminal Appressorial Cell Differentiation.

    Science.gov (United States)

    Marroquin-Guzman, Margarita; Sun, Guangchao; Wilson, Richard A

    2017-01-01

    The conserved target of rapamycin (TOR) pathway integrates growth and development with available nutrients, but how cellular glucose controls TOR function and signaling is poorly understood. Here, we provide functional evidence from the devastating rice blast fungus Magnaporthe oryzae that glucose can mediate TOR activity via the product of a novel carbon-responsive gene, ABL1, in order to tune cell cycle progression during infection-related development. Under nutrient-free conditions, wild type (WT) M. oryzae strains form terminal plant-infecting cells (appressoria) at the tips of germ tubes emerging from three-celled spores (conidia). WT appressorial development is accompanied by one round of mitosis followed by autophagic cell death of the conidium. In contrast, Δabl1 mutant strains undergo multiple rounds of accelerated mitosis in elongated germ tubes, produce few appressoria, and are abolished for autophagy. Treating WT spores with glucose or 2-deoxyglucose phenocopied Δabl1. Inactivating TOR in Δabl1 mutants or glucose-treated WT strains restored appressorium formation by promoting mitotic arrest at G1/G0 via an appressorium- and autophagy-inducing cell cycle delay at G2/M. Collectively, this work uncovers a novel glucose-ABL1-TOR signaling axis and shows it engages two metabolic checkpoints in order to modulate cell cycle tuning and mediate terminal appressorial cell differentiation. We thus provide new molecular insights into TOR regulation and cell development in response to glucose.

  8. Coupling Temperature Control with Electrochemically Modulated Liquid Chromatography: Fundamental Aspects and Applications

    Energy Technology Data Exchange (ETDEWEB)

    Ponton, Lisa M. [Iowa State Univ., Ames, IA (United States)

    2004-12-19

    The primary focus of the doctoral research presented herein has been the integration of temperature control into electrochemically modulated liquid chromatography (EMLC). The combination of temperature control and the tunable characteristics of carbonaceous EMLC stationary phases have been invaluable in deciphering the subtleties of the retention mechanism. The effects of temperature and Eapp on the retention of several naphthalene disulfonates were therefore examined by the van' Hoff relationship. The results indicate that while the retention of both compounds is exothermic at levels comparable to that in many reversed-phase separations, the potential dependence of the separation is actually entropically affected in a manner paralleling that of several classical ion exchange systems. Furthermore, the retention of small inorganic anions at constant temperature also showed evidence of an ion exchange type of mechanism. While a more complete mechanistic description will come from examining the thermodynamics of retention for a wider variety of analytes, this research has laid the groundwork for full exploitation of temperature as a tool to develop retention rules for EMLC. Operating EMLC at elevated temperature and flow conditions has decreased analysis time and has enabled the separation of analytes not normally achievable on a carbon stationary phase. The separation of several aromatic sulfonates was achieved in less than 1 min, a reduction of analysis time by more than a factor of 20 as compared to room temperature separations. The use of higher operating temperatures also facilitated the separation of this mixture with an entirely aqueous mobile phase in less than 2 min. This methodology was extended to the difficult separation of polycyclic aromatic hydrocarbons on PGC. This study also brought to light the mechanistic implications of the unique retention behavior of these analytes through variations of the mobile phase composition.

  9. Pentose Phosphate Shunt Modulates Reactive Oxygen Species and Nitric Oxide Production Controlling Trypanosoma cruzi in Macrophages

    Directory of Open Access Journals (Sweden)

    Sue-jie Koo

    2018-02-01

    Full Text Available Metabolism provides substrates for reactive oxygen species (ROS and nitric oxide (NO generation, which are a part of the macrophage (Mφ anti-microbial response. Mφs infected with Trypanosoma cruzi (Tc produce insufficient levels of oxidative species and lower levels of glycolysis compared to classical Mφs. How Mφs fail to elicit a potent ROS/NO response during infection and its link to glycolysis is unknown. Herein, we evaluated for ROS, NO, and cytokine production in the presence of metabolic modulators of glycolysis and the Krebs cycle. Metabolic status was analyzed by Seahorse Flux Analyzer and mass spectrometry and validated by RNAi. Tc infection of RAW264.7 or bone marrow-derived Mφs elicited a substantial increase in peroxisome proliferator-activated receptor (PPAR-α expression and pro-inflammatory cytokine release, and moderate levels of ROS/NO by 18 h. Interferon (IFN-γ addition enhanced the Tc-induced ROS/NO release and shut down mitochondrial respiration to the levels noted in classical Mφs. Inhibition of PPAR-α attenuated the ROS/NO response and was insufficient for complete metabolic shift. Deprivation of glucose and inhibition of pyruvate transport showed that Krebs cycle and glycolysis support ROS/NO generation in Tc + IFN-γ stimulated Mφs. Metabolic profiling and RNAi studies showed that glycolysis-pentose phosphate pathway (PPP at 6-phosphogluconate dehydrogenase was essential for ROS/NO response and control of parasite replication in Mφ. We conclude that IFN-γ, but not inhibition of PPAR-α, supports metabolic upregulation of glycolytic-PPP for eliciting potent ROS/NO response in Tc-infected Mφs. Chemical analogs enhancing the glucose-PPP will be beneficial in controlling Tc replication and dissemination by Mφs.

  10. Modulation of electrostatic interactions to improve controlled drug delivery from nanogels

    Energy Technology Data Exchange (ETDEWEB)

    Mauri, Emanuele; Chincarini, Giulia M.F.; Rigamonti, Riccardo; Magagnin, Luca; Sacchetti, Alessandro, E-mail: alessandro.sacchetti@polimi.it; Rossi, Filippo, E-mail: filippo.rossi@polimi.it

    2017-03-01

    The synthesis of nanogels as devices capable to maintain the drug level within a desired range for a long and sustained period of time is a leading strategy in controlled drug delivery. However, with respect to the good results obtained with antibodies and peptides there are a lot of problems related to the quick and uncontrolled diffusion of small hydrophilic molecules through polymeric network pores. For these reasons research community is pointing toward the use of click strategies to reduce release rates of the linked drugs to the polymer chains. Here we propose an alternative method that considers the electrostatic interactions between polymeric chains and drugs to tune the release kinetics from nanogel network. The main advantage of these systems lies in the fact that the carried drugs are not modified and no chemical reactions take place during their loading and release. In this work we synthesized PEG-PEI based nanogels with different protonation degrees and the release kinetics with charged and uncharged drug mimetics (sodium fluorescein, SF, and rhodamine B, RhB) were studied. Moreover, also the effect of counterion used to induce protonation was taken into account in order to build a tunable drug delivery system able to provide multiple release rates with the same device. - Highlights: • The design of nanogels as drug delivery systems based on electrostatic interaction among drug and polymers is proposed. • Nanogels can be synthetized tuning their positive charge density, according to the protonation of PEI at different pH. • No biorthogonal chemistry strategies are applied to the polymers or drugs. • Drug release is efficiently modulated by charge density of PEI chains. • The effect of counterion on nanogel synthesis is investigated and allows controlling the drug release.

  11. Motivational intensity modulates the effects of positive emotions on set shifting after controlling physiological arousal.

    Science.gov (United States)

    Zhou, Ya; Siu, Angela F Y

    2015-12-01

    Recent research on the construct of emotion suggests the integration of a motivational dimension into the traditional two-dimension (subjective valence and physiological arousal) model. The motivational intensity of an emotional state should be taken into account while investigating the emotion-cognition relationship. This study examined how positive emotional states varying in motivational intensity influenced set shifting, after controlling the potential confounding impacts of physiological arousal. In Experiment 1, 155 volunteers performed a set-shifting task after being randomly assigned to five states: high- vs. low-motivating positive affect (interest vs. serenity), high- vs. low-motivating negative affect (disgust vs. anxiety), and neutral state. Eighty-five volunteers participated in Experiment 2, which further examined the effects of higher vs. lower degree of interest. Both experiments measured and compared participants' physiological arousal (blood pressure and pulse rate) under the normal and experimental conditions as the covariate. Results showed no difference in switching performance between the neutral and serenity groups. As compared with the neutral state, the high-motivating positive affect significantly increased set-switching reaction time costs, but reduced error rate costs; the higher the motivational intensity, the greater the time-costs impairment. This indicates a role of the high-motivating positive affect in regulating the balance between the flexible and stable cognitive control. Motivational intensity also modulated the effects of negative emotional states, i.e., disgust caused a larger increase in time costs than anxiety. Further exploration into neurobiological mechanisms that may mediate the emotional effects on set shifting is warranted. © 2015 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  12. Local Control After Intensity-Modulated Radiotherapy for Head-and-Neck Rhabdomyosarcoma

    International Nuclear Information System (INIS)

    Curtis, Amarinthia E.; Okcu, M. Fatih; Chintagumpala, Murali; Teh, Bin S.; Paulino, Arnold C.

    2009-01-01

    Purpose: To examine the patterns of failure in patients treated with intensity-modulated radiotherapy (IMRT) for head-and-neck rhabdomyosarcoma (RMS). Methods and Materials: Between 1998 and 2005, 19 patients with a diagnosis of head-and-neck RMS received IMRT at The Methodist Hospital. There were 11 male and 8 female patients, with a median age of 6 years at time of irradiation. Tumor location was parameningeal in 7, orbital in 6, and other head-and-neck RMS in 6. Chemotherapy was given to all patients, with vincristine, actinomycin D, and cyclophosphamide being the most common regimen (n = 18). The median prescribed dose was 5040 cGy. The clinical target volume included the gross tumor volume with a 1.5-cm margin. The median duration of follow-up for surviving patients was 56 months. Results: The 4-year overall survival and local control rates were 76% and 92.9%, respectively. One patient developed a local failure in the high-dose region of the radiation field; there were no marginal failures. Distant metastasis was seen in 4 patients. Overall survival was 42.9% for parameningeal sites and 100% for other sites (p < 0.01). Late toxicities were seen in 7 patients. Two secondary malignancies occurred in 1 child with embryonal RMS of the face and a p53 mutation. Conclusions: Local control was excellent in patients receiving IMRT for head-and-neck RMS. Patterns of local failure reveal no marginal failures in this group of patients

  13. Simultaneous exposure of nematophagous fungi, entomopathogenic nematodes and entomopathogenic fungi can modulate belowground insect pest control.

    Science.gov (United States)

    Bueno-Pallero, Francisco Ángel; Blanco-Pérez, Rubén; Dionísio, Lídia; Campos-Herrera, Raquel

    2018-05-01

    Entomopathogenic nematodes (EPNs) and fungi (EPF) are well known biological control agents (BCAs) against insect pests. Similarly, the nematophagous fungi (NF) are considered good BCA candidates for controlling plant parasitic nematodes. Because NF can employ EPNs as food and interact with EPF, we speculate that the simultaneous application of EPNs and EPF might result in higher insect mortality, whereas the triple species combination with NF will reduce the EPN and EPF activity by predation or inhibition. Here we evaluated single, dual (EPN + EPF, EPF + NF, EPN + NF) and triple (EPN + EPF + NF) combinations of one EPN, Steinernema feltiae (Rhabditida: Steinernematidae), one EPF, Beauveria bassiana (Hypocreales: Clavicipitaceae), and two NF, Arthrobotrys musiformis (Orbiliales: Orbiliaceae) and Purpureocillium lilacinum (Hypocreales: Ophiocordycipitaceae) under laboratory conditions. First, we showed that EPF reduced the growth rate of NF and vice versa when combined in both rich and limiting media, suggesting a negative interaction when combining both fungi. Three different fungal applications (contact with mycelia-conidia, immersion in conidial suspension, and injection of conidial suspension) were tested in single, dual and triple species combinations, evaluating Galleria mellonella (Lepidoptera: Pyralidae) larval mortality and time to kill. When mycelia was presented, the EPF appeared to be the dominant in combined treatments, whereas in immersion exposure was the EPN. In both types of exposure, NF alone did not produce any effect on larvae. However, when A. musiformis was injected, it produced larval mortalities >70% in the same time span as EPN. Overall, additive effects dominated the dual and triple combinations, with the exception of injection method, where synergisms occurred for both NF species combined with EPN + EPF. This study illustrates how differences in species combination and timing of fungal arrival can modulate the action

  14. Modulation and Control of Charge Transport Through Single-Molecule Junctions.

    Science.gov (United States)

    Wang, Kun; Xu, Bingqian

    2017-02-01

    The ability to modulate and control charge transport though single-molecule junction devices is crucial to achieving the ultimate goal of molecular electronics: constructing real-world-applicable electronic components from single molecules. This review aims to highlight the progress made in single-molecule electronics, emphasizing the development of molecular junction electronics in recent years. Among many techniques that attempt to wire a molecule to metallic electrodes, the single-molecule break junction (SMBJ) technique is one of the most reliable and tunable experimental platforms for achieving metal-molecule-metal configurations. It also provides great freedom to tune charge transport through the junction. Soon after the SMBJ technique was introduced, it was extensively used to measure the conductances of individual molecules; however, different conductances were obtained for the same molecule, and it proved difficult to interpret this wide distribution of experimental data. This phenomenon was later found to be mainly due to a lack of precise experimental control and advanced data analysis methods. In recent years, researchers have directed considerable effort into advancing the SMBJ technique by gaining a deeper physical understanding of charge transport through single molecules and thus enhancing its potential applicability in functional molecular-scale electronic devices, such as molecular diodes and molecular transistors. In parallel with that research, novel data analysis methods and approaches that enable the discovery of hidden yet important features in the data are being developed. This review discusses various aspects of molecular junction electronics, from the initial goal of molecular electronics, the development of experimental techniques for creating single-molecule junctions and determining single-molecule conductance, to the characterization of functional current-voltage features and the investigation of physical properties other than charge

  15. Quality controls in intensity-modulated conformational radiotherapy. S.F.P.M. report nr 26, January 2010

    International Nuclear Information System (INIS)

    Valinta, Danielle; Poinsignon, Anne; Caron, Jerome; Dejean, Catherine; Corsetti, Dominique; Marcie, Serge; Mazurier, Jocelyne; Naudy, Suzanne; Aget, Helene; Marchesi, Vincent; Vieillevigne, Laure; Dedieu, Veronique; Bramoule, Celine; Caselles, Olivier; Lacaze, Brigitte; Mazurier, Jocelyne

    2009-08-01

    This report proposes a comprehensive presentation of the different controls which can be performed for the implementation of 3D intensity-modulated conformal radiation therapy (IMCR). The authors first present the IMCR principle by describing modes of production of modulated beams, the practical realisation of intensity modulation with Multi Leaf Collimator (MLC), multi leaf collimators, and the inverse planning system. They present the quality control of the accelerator (pre-requisites, linearity of the monitor chamber, symmetry and homogeneity), the quality control of multi leaf collimators (prerequisites, leaf absolute calibration, static mode, dynamic mode), the quality control of the treatment planning system (prerequisites, tests specific to IMCR, example in dynamic mode with the chair test), the quality control of the treatment plan (objective, necessary equipment and software solutions, measurement of point absolute dose, control of dose distribution, independent calculation of the number of monitor units), and the treatment verification (pre-treatment verification, patient repositioning during treatment). Finally, they indicate human means required for IMCR implementation, and formulate some recommendations for this implementation

  16. The μs and ns mode modulation system for grid controlled gun of the HESYRL linac

    International Nuclear Information System (INIS)

    Wang, Guicheng; Hong, Jun; Pei, Yuanji

    1988-01-01

    A μs and ns mode modulation system has been developed for the grid-controlled gun in the HESYRL. The gun drived by this system generated 1A and 500 MA pulse current for μs and ns mode respectively. In the ns mode modulation pulse formulation system, the sharper was built up using one transistor 3DA87D as avalanche switch and a shortcircuit coaxal cable as waveform sharp element. Outline of the μs mode system and details of the ns mode system are presented. (author)

  17. Pulse-density modulation control of chemical oscillation far from equilibrium in a droplet open-reactor system.

    Science.gov (United States)

    Sugiura, Haruka; Ito, Manami; Okuaki, Tomoya; Mori, Yoshihito; Kitahata, Hiroyuki; Takinoue, Masahiro

    2016-01-20

    The design, construction and control of artificial self-organized systems modelled on dynamical behaviours of living systems are important issues in biologically inspired engineering. Such systems are usually based on complex reaction dynamics far from equilibrium; therefore, the control of non-equilibrium conditions is required. Here we report a droplet open-reactor system, based on droplet fusion and fission, that achieves dynamical control over chemical fluxes into/out of the reactor for chemical reactions far from equilibrium. We mathematically reveal that the control mechanism is formulated as pulse-density modulation control of the fusion-fission timing. We produce the droplet open-reactor system using microfluidic technologies and then perform external control and autonomous feedback control over autocatalytic chemical oscillation reactions far from equilibrium. We believe that this system will be valuable for the dynamical control over self-organized phenomena far from equilibrium in chemical and biomedical studies.

  18. Emotional modulation of control dilemmas: the role of positive affect, reward, and dopamine in cognitive stability and flexibility.

    Science.gov (United States)

    Goschke, Thomas; Bolte, Annette

    2014-09-01

    Goal-directed action in changing environments requires a dynamic balance between complementary control modes, which serve antagonistic adaptive functions (e.g., to shield goals from competing responses and distracting information vs. to flexibly switch between goals and behavioral dispositions in response to significant changes). Too rigid goal shielding promotes stability but incurs a cost in terms of perseveration and reduced flexibility, whereas too weak goal shielding promotes flexibility but incurs a cost in terms of increased distractibility. While research on cognitive control has long been conducted relatively independently from the study of emotion and motivation, it is becoming increasingly clear that positive affect and reward play a central role in modulating cognitive control. In particular, evidence from the past decade suggests that positive affect not only influences the contents of cognitive processes, but also modulates the balance between complementary modes of cognitive control. In this article we review studies from the past decade that examined effects of induced positive affect on the balance between cognitive stability and flexibility with a focus on set switching and working memory maintenance and updating. Moreover, we review recent evidence indicating that task-irrelevant positive affect and performance-contingent rewards exert different and sometimes opposite effects on cognitive control modes, suggesting dissociations between emotional and motivational effects of positive affect. Finally, we critically review evidence for the popular hypothesis that effects of positive affect may be mediated by dopaminergic modulations of neural processing in prefrontal and striatal brain circuits, and we refine this "dopamine hypothesis of positive affect" by specifying distinct mechanisms by which dopamine may mediate effects of positive affect and reward on cognitive control. We conclude with a discussion of limitations of current research, point to

  19. Analysis of bus width and delay on a fully digital signum nonlinearity chaotic oscillator

    KAUST Repository

    Mansingka, Abhinav S.

    2012-07-29

    This paper introduces the first fully digital implementation of a 3rd order ODE-based chaotic oscillator with signum nonlinearity. A threshold bus width of 12-bits for reliable chaotic behavior is observed, below which the system output becomes periodic. Beyond this threshold, the maximum Lyapunov exponent (MLE) is shown to improve up to a peak value at 16-bits and subsequently decrease with increasing bus width. The MLE is also shown to gradually increase with number of introduced internal delay cycles until a peak value at 14 cycles, after which the system loses chaotic properties. Introduced external delay cycles are shown to rotate the attractors in 3-D phase space. Bus width and delay elements can be independently modulated to optimize the system to suit specifications. The experimental results of the system show low area and high performance on a Xilinx Virtex 4 FPGA with throughput of 13.35 Gbits/s for a 32-bit implementation.

  20. Analysis of bus width and delay on a fully digital signum nonlinearity chaotic oscillator

    KAUST Repository

    Mansingka, Abhinav S.; Radwan, Ahmed G.; Salama, Khaled N.; Zidan, Mohammed A.

    2012-01-01

    This paper introduces the first fully digital implementation of a 3rd order ODE-based chaotic oscillator with signum nonlinearity. A threshold bus width of 12-bits for reliable chaotic behavior is observed, below which the system output becomes periodic. Beyond this threshold, the maximum Lyapunov exponent (MLE) is shown to improve up to a peak value at 16-bits and subsequently decrease with increasing bus width. The MLE is also shown to gradually increase with number of introduced internal delay cycles until a peak value at 14 cycles, after which the system loses chaotic properties. Introduced external delay cycles are shown to rotate the attractors in 3-D phase space. Bus width and delay elements can be independently modulated to optimize the system to suit specifications. The experimental results of the system show low area and high performance on a Xilinx Virtex 4 FPGA with throughput of 13.35 Gbits/s for a 32-bit implementation.

  1. Evaluation of an active learning module to teach hazard and risk in Hazard Analysis and Critical Control Points (HACCP classes

    Directory of Open Access Journals (Sweden)

    Omar A. Oyarzabal

    2017-04-01

    Full Text Available The terms hazard and risk are significant building blocks for the organization of risk-based food safety plans. Unfortunately, these terms are not clear for some personnel working in food manufacturing facilities. In addition, there are few examples of active learning modules for teaching adult participants the principles of hazard analysis and critical control points (HACCP. In this study, we evaluated the effectiveness of an active learning module to teach hazard and risk to participants of HACCP classes provided by the University of Vermont Extension in 2015 and 2016. This interactive module is comprised of a questionnaire; group playing of a dice game that we have previously introduced in the teaching of HACCP; the discussion of the terms hazard and risk; and a self-assessment questionnaire to evaluate the teaching of hazard and risk. From 71 adult participants that completed this module, 40 participants (56% provided the most appropriate definition of hazard, 19 participants (27% provided the most appropriate definition of risk, 14 participants (20% provided the most appropriate definitions of both hazard and risk, and 23 participants (32% did not provide an appropriate definition for hazard or risk. Self-assessment data showed an improvement in the understanding of these terms (P < 0.05. Thirty participants (42% stated that the most valuable thing they learned with this interactive module was the difference between hazard and risk, and 40 participants (65% responded that they did not attend similar presentations in the past. The fact that less than one third of the participants answered properly to the definitions of hazard and risk at baseline is not surprising. However, these results highlight the need for the incorporation of modules to discuss these important food safety terms and include more active learning modules to teach food safety classes. This study suggests that active learning helps food personnel better understand important

  2. Direct measurement of the W boson width

    Energy Technology Data Exchange (ETDEWEB)

    Abazov, V.M.; /Dubna, JINR; Abbott, B.; /Oklahoma U.; Abolins, M.; /Michigan State U.; Acharya, B.S.; /Tata Inst.; Adams, M.; /Illinois U., Chicago; Adams, T.; /Florida State U.; Aguilo, E.; /Alberta U. /Simon Fraser U. /McGill U.; Ahsan, M.; /Kansas State U.; Alexeev, G.D.; /Dubna, JINR; Alkhazov, G.; /St. Petersburg, INP; Alton, A.; /Michigan U. /Northeastern U.

    2009-09-01

    We present a direct measurement of the width of the W boson using the shape of the transverse mass distribution of W {yields} e{nu} candidates selected in 1 fb{sup -1} of data collected with the D0 detector at the Fermilab Tevatron collider in p{bar p} collisions at {radical}s = 1.96 TeV. We use the same methods and data sample that were used for our recently published W boson mass measurement, except for the modeling of the recoil, which is done with a new method based on a recoil library. Our result, 2.028 {+-} 0.072 GeV, is in agreement with the predictions of the standard model and is the most precise direct measurement result from a single experiment to date.

  3. Width lines of non hydrogenoid ions

    International Nuclear Information System (INIS)

    Bertuccelli, D.; Bertuccelli, G.; Di Rocco, H.O.

    1990-01-01

    An extensive theoretical and experimental work was carried out on the ns-np and np-nd line widths (w) of noble gases after ionization (n=n 0 +1, were n 0 is the principal quantum number of the fundamental configuration). A high current 'pinch' discharge was used as source. Electron density and temperature were estimated to be N e =2.65x10 16 cm -3 and T=1.45x10 4 K respectively. Calculations were based on a semi-empirical approximation and the matrix elements (or transition probabilities) were evaluated in different approximation. Comparing our measurements with those of other authors, a systematic tendency, with a dependence on atomic number Z and ionization energy of the higher level L, was established. Finally, it has been established that for N e >10 17 cm -3 , w ∝ N e γ , where γ=5/6. (Author). 8 refs., 1 fig., 1 tab

  4. Lake Basin Fetch and Maximum Length/Width

    Data.gov (United States)

    Minnesota Department of Natural Resources — Linear features representing the Fetch, Maximum Length and Maximum Width of a lake basin. Fetch, maximum length and average width are calcuated from the lake polygon...

  5. Evaluation of an active learning module to teach hazard and risk in Hazard Analysis and Critical Control Points (HACCP) classes.

    Science.gov (United States)

    Oyarzabal, Omar A; Rowe, Ellen

    2017-04-01

    The terms hazard and risk are significant building blocks for the organization of risk-based food safety plans. Unfortunately, these terms are not clear for some personnel working in food manufacturing facilities. In addition, there are few examples of active learning modules for teaching adult participants the principles of hazard analysis and critical control points (HACCP). In this study, we evaluated the effectiveness of an active learning module to teach hazard and risk to participants of HACCP classes provided by the University of Vermont Extension in 2015 and 2016. This interactive module is comprised of a questionnaire; group playing of a dice game that we have previously introduced in the teaching of HACCP; the discussion of the terms hazard and risk; and a self-assessment questionnaire to evaluate the teaching of hazard and risk. From 71 adult participants that completed this module, 40 participants (56%) provided the most appropriate definition of hazard, 19 participants (27%) provided the most appropriate definition of risk, 14 participants (20%) provided the most appropriate definitions of both hazard and risk, and 23 participants (32%) did not provide an appropriate definition for hazard or risk. Self-assessment data showed an improvement in the understanding of these terms (P active learning modules to teach food safety classes. This study suggests that active learning helps food personnel better understand important food safety terms that serve as building blocks for the understanding of more complex food safety topics.

  6. Half-width at half-maximum, full-width at half-maximum analysis

    Indian Academy of Sciences (India)

    addition to the well-defined parameter full-width at half-maximum (FWHM). The distribution of ... optical side-lobes in the diffraction pattern resulting in steep central maxima [6], reduc- tion of effects of ... and broad central peak. The idea of.

  7. Glomerular epithelial foot processes in normal man and rats. Distribution of true width and its intra- and inter-individual variation.

    Science.gov (United States)

    Gundersen, H J; Seefeldt, T; Osterby, R

    1980-01-01

    The width of individual glomerular epithelial foot processes appears very different on electron micrographs. A method for obtainining distributions of the true width of foot processes from that of their apparent width on electron micrographs has been developed based on geometric probability theory pertaining to a specific geometric model. Analyses of foot process width in humans and rats show a remarkable interindividual invariance implying rigid control and therefore great biological significance of foot process width or a derivative thereof. The very low inter-individual variation of the true width, shown in the present paper, makes it possible to demonstrate slight changes in rather small groups of patients or experimental animals.

  8. Second generation SLAC modulator

    International Nuclear Information System (INIS)

    Donaldson, A.R.; Cron, J.C.; Hanselman, R.R.

    1986-06-01

    The Stanford Linear Accelerator Laboratory has undertaken the construction of a single pass electron-positron collider. In order to reach required beam energy 235 new klystrons needed upgraded modulator systems. The collider will use 50 GeV electrons and positrons. The increase in accelerator energy from the present 30 GeV necessitates the replacement of existing 35 MW klystrons with new 67 MW units. The doubling of klystron output power required a redesign of the modulator system. The 67 MW klystron needs a 350 kV beam voltage pulse with a 3.7 μs pulse width. A new pulse transformer was designed to deliver the increased voltage and pulse width. Pulse cable design was evaluated to obtain increased reliability of that critical element. The modulator, with the exception of its power supply, was rebuilt to produce the required power increase while enhancing reliability and improving maintainability. An investigation of present thyratron switch tube performance under the new operating conditions resulted in agitation and some warranted panic but these conditions were mitigated after several successful experiments and some evolutionary narrowing of the klystron pulse width. The discussion will cover the upgraded modulator system specifications and some details of the new pulse transformer tank, pulse cable, modulator, and modulator switch tube

  9. Performance analysis of joint diversity combining, adaptive modulation, and power control schemes

    KAUST Repository

    Qaraqe, Khalid A.; Bouida, Zied; Alouini, Mohamed-Slim

    2011-01-01

    Adaptive modulation and diversity combining represent very important adaptive solutions for future generations of wireless communication systems. Indeed, in order to improve the performance and the efficiency of these systems, these two techniques

  10. Characterizing graphs of maximum matching width at most 2

    DEFF Research Database (Denmark)

    Jeong, Jisu; Ok, Seongmin; Suh, Geewon

    2017-01-01

    The maximum matching width is a width-parameter that is de ned on a branch-decomposition over the vertex set of a graph. The size of a maximum matching in the bipartite graph is used as a cut-function. In this paper, we characterize the graphs of maximum matching width at most 2 using the minor o...

  11. Acquired self-control of insula cortex modulates emotion recognition and brain network connectivity in schizophrenia.

    Science.gov (United States)

    Ruiz, Sergio; Lee, Sangkyun; Soekadar, Surjo R; Caria, Andrea; Veit, Ralf; Kircher, Tilo; Birbaumer, Niels; Sitaram, Ranganatha

    2013-01-01

    Real-time functional magnetic resonance imaging (rtfMRI) is a novel technique that has allowed subjects to achieve self-regulation of circumscribed brain regions. Despite its anticipated therapeutic benefits, there is no report on successful application of this technique in psychiatric populations. The objectives of the present study were to train schizophrenia patients to achieve volitional control of bilateral anterior insula cortex on multiple days, and to explore the effect of learned self-regulation on face emotion recognition (an extensively studied deficit in schizophrenia) and on brain network connectivity. Nine patients with schizophrenia were trained to regulate the hemodynamic response in bilateral anterior insula with contingent rtfMRI neurofeedback, through a 2-weeks training. At the end of the training stage, patients performed a face emotion recognition task to explore behavioral effects of learned self-regulation. A learning effect in self-regulation was found for bilateral anterior insula, which persisted through the training. Following successful self-regulation, patients recognized disgust faces more accurately and happy faces less accurately. Improvements in disgust recognition were correlated with levels of self-activation of right insula. RtfMRI training led to an increase in the number of the incoming and outgoing effective connections of the anterior insula. This study shows for the first time that patients with schizophrenia can learn volitional brain regulation by rtfMRI feedback training leading to changes in the perception of emotions and modulations of the brain network connectivity. These findings open the door for further studies of rtfMRI in severely ill psychiatric populations, and possible therapeutic applications. Copyright © 2011 Wiley Periodicals, Inc.

  12. Reinforcement learning modulates the stability of cognitive control settings for object selection

    Directory of Open Access Journals (Sweden)

    Anthony William Sali

    2013-12-01

    Full Text Available Cognitive flexibility reflects both a trait that reliably differs between individuals and a state that can fluctuate moment-to-moment. Whether individuals can undergo persistent changes in cognitive flexibility as a result of reward learning is less understood. Here, we investigated whether reinforcing a periodic shift in an object selection strategy can make an individual more prone to switch strategies in a subsequent unrelated task. Participants completed two different choice tasks in which they selected one of four objects in an attempt to obtain a hidden reward on each trial. During a training phase, objects were defined by color. Participants received either consistent reward contingencies in which one color was more often rewarded, or contingencies in which the color that was more often rewarded changed periodically and without warning. Following the training phase, all participants completed a test phase in which reward contingencies were defined by spatial location and the location that was more often rewarded remained constant across the entire task. Those participants who received inconsistent contingencies during training continued to make more variable selections during the test phase in comparison to those who received the consistent training. Furthermore, a difference in the likelihood to switch selections on a trial-by-trial basis emerged between training groups: participants who received consistent contingencies during training were less likely to switch object selections following an unrewarded trial and more likely to repeat a selection following reward. Our findings provide evidence that the extent to which priority shifting is reinforced modulates the stability of cognitive control settings in a persistent manner, such that individuals become generally more or less prone to shifting priorities in the future.

  13. Emotional and cognitive processing of narratives and individual appraisal styles: recruitment of cognitive control networks vs. modulation of deactivations

    Directory of Open Access Journals (Sweden)

    Enrico eBenelli

    2012-08-01

    Full Text Available Research in psychotherapy has shown that the frequency of use of specific classes of words (such as terms with emotional valence in descriptions of scenes of affective relevance is a possible indicator of psychological affective functioning. Using functional magnetic resonance imaging, we investigated the neural correlates of these linguistic markers in narrative texts depicting core aspects of emotional experience in human interaction, and their modulation by individual differences in the propensity to use these markers. Emotional words activated both lateral and medial aspects of the prefrontal cortex, as in previous studies of instructed emotion regulation and in consistence with recruitment of effortful control processes. However, individual differences in the spontaneous use of emotional terms in characterizing the stimulus material were prevalently associated with modulation of the signal in the perigenual cortex, in the retrosplenial cortex and precuneus, and the anterior insula/ventrolateral prefrontal cortex. Modulation of signal by the presence of these textual markers or individual differences mostly involved areas deactivated by the main task, thus further differentiating neural correlates of these appraisal styles from those associated with effortful control. These findings are discussed in the context of reports in the literature of modulations of deactivations, which suggest their importance in orienting attention and generation of response in the presence of emotional information. These findings suggest that deactivations may play a functional role in emotional appraisal and may contribute to characterizing different appraisal styles.

  14. An autobias control system for the electro—optic modulator used in a quantum key distribution system

    International Nuclear Information System (INIS)

    Chen Wen-Fen; Wei Zheng-Jun; Guo Li; Hou Li-Yan; Wang Geng; Wang Jin-Dong; Zhang Zhi-Ming; Guo Jian-Ping; Liu Song-Hao

    2014-01-01

    In a quantum key distribution system, it is crucial to keep the extinction ratio of the coherent pulses stable. This means that the direct current bias point of the electro—optic modulator (EOM) used for generating coherent pulses must be locked. In this paper, an autobias control system based on a lock-in-amplifier for the EOM is introduced. Its drift information extracting theory and control method are analyzed comprehensively. The long term drift of the extinction ratio of the coherent pulses is measured by a single photon detector, which indicates that the autobias control system is effective for stabilizing the bias point of the EOM. (general)

  15. Modulation of controlled-not gate using light beams carrying orbital angular momentum in a nonlinear atomic vapor

    Science.gov (United States)

    Zhang, Yan; Li, YuanYuan; Zhang, YunZhe

    2018-03-01

    We propose and experimentally demonstrate a controlled-not gate with light beams carrying orbital angular momentum (OAM) through a degenerate four-wave mixing process via a photonic band gap structure satisfying the phase-matching condition. By employing the different topological charges of a Laguerre-Gaussian beam as a qubit in this nonlinear process, the controlled-not gate with OAM can be realized. Moreover, we investigate the evolution of the controlled-not gate, which can be modulated by the frequency and the power of the incident beam, i.e., under electromagnetically induced transparency conditions. The study results are useful for applications in quantum communication and information storage.

  16. Computerized Torque Control for Large dc Motors

    Science.gov (United States)

    Willett, Richard M.; Carroll, Michael J.; Geiger, Ronald V.

    1987-01-01

    Speed and torque ranges in generator mode extended. System of shunt resistors, electronic switches, and pulse-width modulation controls torque exerted by large, three-phase, electronically commutated dc motor. Particularly useful for motor operating in generator mode because it extends operating range to low torque and high speed.

  17. Volumetric modulated arc therapy for lung stereotactic radiation therapy can achieve high local control rates.

    Science.gov (United States)

    Yamashita, Hideomi; Haga, Akihiro; Takahashi, Wataru; Takenaka, Ryousuke; Imae, Toshikazu; Takenaka, Shigeharu; Nakagawa, Keiichi

    2014-11-11

    The aim of this study was to report the outcome of primary or metastatic lung cancer patients undergoing volumetric modulated arc therapy for stereotactic body radiation therapy (VMAT-SBRT). From October 2010 to December 2013, consecutive 67 lung cancer patients received single-arc VMAT-SBRT using an Elekta-synergy system. All patients were treated with an abdominal compressor. The gross tumor volumes were contoured on 10 respiratory phases computed tomography (CT) datasets from 4-dimensional (4D) CT and merged into internal target volumes (ITVs). The planning target volume (PTV) margin was isotropically taken as 5 mm. Treatment was performed with a D95 prescription of 50 Gy (43 cases) or 55 Gy (12 cases) in 4 fractions for peripheral tumor or 56 Gy in 7 fractions (12 cases) for central tumor. Among the 67 patients, the median age was 73 years (range, 59-95 years). Of the patients, male was 72% and female 28%. The median Karnofsky performance status was 90-100% in 39 cases (58%) and 80-90% in 20 cases (30%). The median follow-up was 267 days (range, 40-1162 days). Tissue diagnosis was performed in 41 patients (61%). There were T1 primary lung tumor in 42 patients (T1a in 28 patients, T1b in 14 patients), T2 in 6 patients, three T3 in 3 patients, and metastatic lung tumor in 16 patients. The median mean lung dose was 6.87 Gy (range, 2.5-15 Gy). Six patients (9%) developed radiation pneumonitis required by steroid administration. Actuarial local control rate were 100% and 100% at 1 year, 92% and 75% at 2 years, and 92% and 75% at 3 years in primary and metastatic lung cancer, respectively (p =0.59). Overall survival rate was 83% and 84% at 1 year, 76% and 53% at 2 years, and 46% and 20% at 3 years in primary and metastatic lung cancer, respectively (p =0.12). Use of VMAT-based delivery of SBRT in primary in metastatic lung tumors demonstrates high local control rates and low risk of normal tissue complications.

  18. Volumetric modulated arc therapy for lung stereotactic radiation therapy can achieve high local control rates

    International Nuclear Information System (INIS)

    Yamashita, Hideomi; Haga, Akihiro; Takahashi, Wataru; Takenaka, Ryousuke; Imae, Toshikazu; Takenaka, Shigeharu; Nakagawa, Keiichi

    2014-01-01

    The aim of this study was to report the outcome of primary or metastatic lung cancer patients undergoing volumetric modulated arc therapy for stereotactic body radiation therapy (VMAT-SBRT). From October 2010 to December 2013, consecutive 67 lung cancer patients received single-arc VMAT-SBRT using an Elekta-synergy system. All patients were treated with an abdominal compressor. The gross tumor volumes were contoured on 10 respiratory phases computed tomography (CT) datasets from 4-dimensional (4D) CT and merged into internal target volumes (ITVs). The planning target volume (PTV) margin was isotropically taken as 5 mm. Treatment was performed with a D95 prescription of 50 Gy (43 cases) or 55 Gy (12 cases) in 4 fractions for peripheral tumor or 56 Gy in 7 fractions (12 cases) for central tumor. Among the 67 patients, the median age was 73 years (range, 59–95 years). Of the patients, male was 72% and female 28%. The median Karnofsky performance status was 90-100% in 39 cases (58%) and 80-90% in 20 cases (30%). The median follow-up was 267 days (range, 40–1162 days). Tissue diagnosis was performed in 41 patients (61%). There were T1 primary lung tumor in 42 patients (T1a in 28 patients, T1b in 14 patients), T2 in 6 patients, three T3 in 3 patients, and metastatic lung tumor in 16 patients. The median mean lung dose was 6.87 Gy (range, 2.5-15 Gy). Six patients (9%) developed radiation pneumonitis required by steroid administration. Actuarial local control rate were 100% and 100% at 1 year, 92% and 75% at 2 years, and 92% and 75% at 3 years in primary and metastatic lung cancer, respectively (p = 0.59). Overall survival rate was 83% and 84% at 1 year, 76% and 53% at 2 years, and 46% and 20% at 3 years in primary and metastatic lung cancer, respectively (p = 0.12). Use of VMAT-based delivery of SBRT in primary in metastatic lung tumors demonstrates high local control rates and low risk of normal tissue complications

  19. Design and implementation of predictive current control of three-phase PWM rectifier using space-vector modulation (SVM)

    International Nuclear Information System (INIS)

    Bouafia, Abdelouahab; Gaubert, Jean-Paul; Krim, Fateh

    2010-01-01

    This paper is concerned with the design and implementation of current control of three-phase PWM rectifier based on predictive control strategy. The proposed predictive current control technique operates with constant switching frequency, using space-vector modulation (SVM). The main goal of the designed current control scheme is to maintain the dc-bus voltage at the required level and to achieve the unity power factor (UPF) operation of the converter. For this purpose, two predictive current control algorithms, in the sense of deadbeat control, are developed for direct controlling input current vector of the converter in the stationary α-β and rotating d-q reference frame, respectively. For both predictive current control algorithms, at the beginning of each switching period, the required rectifier average voltage vector allowing the cancellation of both tracking errors of current vector components at the end of the switching period, is computed and applied during a predefined switching period by means of SVM. The main advantages of the proposed predictive current control are that no need to use hysteresis comparators or PI controllers in current control loops, and constant switching frequency. Finally, the developed predictive current control algorithms were tested both in simulations and experimentally, and illustrative results are presented here. Results have proven excellent performance in steady and transient states, and verify the validity of the proposed predictive current control which is compared to other control strategies.

  20. Multi-hit time-to-amplitude CAMAC module (MTAC)

    International Nuclear Information System (INIS)

    Kang, H.

    1980-10-01

    A Multi-Hit Time-to-Amplitude Module (MTAC) for the SLAC Mark III drift chamber system has been designed to measure drift time by converting time-proportional chamber signals into analog levels, and converting the analog data by slow readout via a semi-autonomous controller in a CAMAC crate. The single width CAMAC module has 16 wire channels, each with a 4-hit capacity. An externally generated common start initiates an internal precision ramp voltage which is then sampled using a novel shift register gating scheme and CMOS sampling switches. The detailed design and performance specifications are described

  1. Dosimetric advantages of intensity-modulated proton therapy for oropharyngeal cancer compared with intensity-modulated radiation: A case-matched control analysis

    Energy Technology Data Exchange (ETDEWEB)

    Holliday, Emma B. [Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Kocak-Uzel, Esengul [Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Department of Radiation Therapy, Beykent University, Istanbul (Turkey); Feng, Lei [Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Thaker, Nikhil G.; Blanchard, Pierre; Rosenthal, David I.; Gunn, G. Brandon; Garden, Adam S. [Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX (United States); Frank, Steven J., E-mail: sjfrank@mdanderson.org [Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX (United States)

    2016-10-01

    A potential advantage of intensity-modulated proton therapy (IMPT) over intensity-modulated (photon) radiation therapy (IMRT) in the treatment of oropharyngeal carcinoma (OPC) is lower radiation dose to several critical structures involved in the development of nausea and vomiting, mucositis, and dysphagia. The purpose of this study was to quantify doses to critical structures for patients with OPC treated with IMPT and compare those with doses on IMRT plans generated for the same patients and with a matched cohort of patients actually treated with IMRT. In this study, 25 patients newly diagnosed with OPC were treated with IMPT between 2011 and 2012. Comparison IMRT plans were generated for these patients and for additional IMRT-treated controls extracted from a database of patients with OPC treated between 2000 and 2009. Cases were matched based on the following criteria, in order: unilateral vs bilateral therapy, tonsil vs base of tongue primary, T-category, N-category, concurrent chemotherapy, induction chemotherapy, smoking status, sex, and age. Results showed that the mean doses to the anterior and posterior oral cavity, hard palate, larynx, mandible, and esophagus were significantly lower with IMPT than with IMRT comparison plans generated for the same cohort, as were doses to several central nervous system structures involved in the nausea and vomiting response. Similar differences were found when comparing dose to organs at risks (OARs) between the IMPT cohort and the case-matched IMRT cohort. In conclusion, these findings suggest that patients with OPC treated with IMPT may experience fewer and less severe side effects during therapy. This may be the result of decreased beam path toxicities with IMPT due to lower doses to several dysphagia, odynophagia, and nausea and vomiting–associated OARs. Further study is needed to evaluate differences in long-term disease control and chronic toxicity between patients with OPC treated with IMPT in comparison to

  2. Beam-width spreading of vortex beams in free space

    Science.gov (United States)

    Wang, Weiwei; Li, Jinhong; Duan, Meiling

    2018-01-01

    Based on the extended Huygens-Fresnel principle and the definition of second-order moments of the Wigner distribution function, the analytical expression for the beam-width spreading of Gaussian Schell-model (GSM) vortex beams in free space are derived, and used to study the influence of beam parameters on the beam-width spreading of GSM vortex beams. With the increment of the propagation distance, the beam-width spreading of GSM vortex beams will increase; the bigger the topological charge, spatial correlation length, wavelength and waist width are, the smaller the beam-width spreading is.

  3. Narrow-width mechanism of a=5 Ξ-state

    International Nuclear Information System (INIS)

    Kumagai-Fuse, I.; Akaishi, Y.

    1995-04-01

    Narrow-width mechanism of ≡ 5 H is discussed by calculating conversion widths to all its possible decay channels. Since the conversion processes have small reaction Q values, the three- and four- body decays are strongly suppressed owing to small phase volumes available. Decay widths to the two-body channels are significantly reduced by the distortion of emitted-particle waves. This mechanism brings about a narrow width of ≡ 5 H. The total width is estimated to be 0.87 MeV, in which the largest contribution comes from the decay into the Λ 4 H * +Λ channel. (author)

  4. A redox responsive, fluorescent supramolecular metallohydrogel consists of nanofibers with single-molecule width

    KAUST Repository

    Zhang, Ye

    2013-04-03

    The integration of a tripeptide derivative, which is a versatile self-assembly motif, with a ruthenium(II)tris(bipyridine) complex affords the first supramolecular metallo-hydrogelator that not only self assembles in water to form a hydrogel but also exhibits gel-sol transition upon oxidation of the metal center. Surprisingly, the incorporation of the metal complex in the hydrogelator results in the nanofibers, formed by the self-assembly of the hydrogelator in water, to have the width of a single molecule of the hydrogelator. These results illustrate that metal complexes, besides being able to impart rich optical, electronic, redox, or magnetic properties to supramolecular hydrogels, also offer a unique geometrical control to prearrange the self-assembly motif prior to self-assembling. The use of metal complexes to modulate the dimensionality of intermolecular interactions may also help elucidate the interactions of the molecular nanofibers with other molecules, thus facilitating the development of supramolecular hydrogel materials for a wide range of applications. © 2013 American Chemical Society.

  5. Thermal Equilibrium Dynamic Control Based on DPWM Dual-Mode Modulation of High Power NPC Three-Level Inverter

    OpenAIRE

    Xu, Shi-Zhou; He, Feng-You

    2016-01-01

    In some special applications of NPC three-level inverters, such as mine hoist, there exist special conditions of overloading during the whole hoisting process and large overload in starting stage, during which the power-loss calculation of power devices and thermal control are important factors affecting the thermal stability of inverters. The principles of SVPWM and DPWM were described in this paper firstly, based on which the dynamic power losses of the two modulations of hoist in single pe...

  6. GAP WIDTH STUDY IN LASER BUTT-WELDING

    DEFF Research Database (Denmark)

    Gong, Hui; Olsen, Flemming Ove

    power : 2 and 2.6 kW and the focal point position : 0 and -1.2 mm. Quality of all the butt welds are destructively tested according to ISO 13919-1.Influences of the variable process parameters to the maximum allowable gap width are observed as (1) the maximum gap width is inversely related......In this paper the maximum allowable gap width in laser butt-welding is intensively studied. The gap width study (GWS) is performed on the material of SST of W1.4401 (AISI 316) under various welding conditions, which are the gap width : 0.00-0.50 mm, the welding speed : 0.5-2.0 m/min, the laser...... to the welding speed, (2) the larger laser power leads to the bigger maximum allowable gap width and (3) the focal point position has very little influence on the maximum gap width....

  7. Distinct sets of locomotor modules control the speed and modes of human locomotion

    Science.gov (United States)

    Yokoyama, Hikaru; Ogawa, Tetsuya; Kawashima, Noritaka; Shinya, Masahiro; Nakazawa, Kimitaka

    2016-01-01

    Although recent vertebrate studies have revealed that different spinal networks are recruited in locomotor mode- and speed-dependent manners, it is unknown whether humans share similar neural mechanisms. Here, we tested whether speed- and mode-dependence in the recruitment of human locomotor networks exists or not by statistically extracting locomotor networks. From electromyographic activity during walking and running over a wide speed range, locomotor modules generating basic patterns of muscle activities were extracted using non-negative matrix factorization. The results showed that the number of modules changed depending on the modes and speeds. Different combinations of modules were extracted during walking and running, and at different speeds even during the same locomotor mode. These results strongly suggest that, in humans, different spinal locomotor networks are recruited while walking and running, and even in the same locomotor mode different networks are probably recruited at different speeds. PMID:27805015

  8. Attention demanding tasks during treadmill walking reduce step width variability in young adults

    Directory of Open Access Journals (Sweden)

    Troy Karen L

    2005-08-01

    demanding task during treadmill walking may reflect a voluntary gait adaptation toward a more conservative gait pattern emphasizing frontal plane control of the trunk. Extension of the experimental paradigm to older adults and mechanistic approaches to link step width variability to dynamic stability, and falls, in a cause-effect manner are necessary.

  9. Quality control and batch testing of MRPC modules for BESIII ETOF upgrade

    Science.gov (United States)

    Liu, Z.; Li, X.; Sun, Y. J.; Li, C.; Heng, Y. K.; Chen, T. X.; Dai, H. L.; Shao, M.; Sun, S. S.; Tang, Z. B.; Yang, R. X.; Wu, Z.; Wang, X. Z.

    2017-12-01

    The end-cap time-of-flight (ETOF) system for the Beijing Spectrometer III (BESIII) has been upgraded using the Multi-gap Resistive Plate Chamber (MRPC) technology (Williams et al., 1999; Li et al., 2001; Blanco et al., 2003; Fonte et al., 2013, [1-4]). A set of quality-assurance procedures has been developed to guarantee the performances of the 72 mass-produced MRPC modules installed. The cosmic ray batch testing show that the average detection efficiency of the MRPC modules is about 95%. Two different calibration methods indicate that MRPCs' time resolution can reach 60 ps in the cosmic ray test.

  10. The FCMM, a Fastbus Control and Memory Module for readout of the DELPHI SAT track detector

    International Nuclear Information System (INIS)

    Wikne, J.C.; Skaali, B.

    1990-02-01

    The Small Angle Tagger (SAT) in the DELPHI experiment at CERN concists of detector units placed close to the beam on both sides of the interaction point. The track detector part of the SAT is built of Si-strip detectors where position can be measured to an accurancy of 1 mm in the radial direction. A specially developed Fastbus module for reading and front end buffering of the data from the track detector is decribed in the report. The description is intended as a complete technical manual for the module. 13 refs.; 27 figs

  11. Experimental control of power dropouts by current modulation in a semiconductor laser with optical feedback

    International Nuclear Information System (INIS)

    Ticos, Catalin M; Andrei, Ionut R; Pascu, Mihail L; Bulinski, Mircea

    2011-01-01

    The injection current of an external-cavity semiconductor laser working in a regime of low-frequency fluctuations (LFFs) is modulated at several MHz. The rate of power dropouts in the laser emission is correlated with the amplitude and frequency of the modulating signal. The occurrence of dropouts becomes more regular when the laser is driven at 7 MHz, which is close to the dominant frequency of dropouts in the solitary laser. Driving the laser at 10 MHz also induces dropouts with a periodicity of 0.1 μs, resulting in LFFs with two dominant frequencies.

  12. Quality control of roll-to-roll processed polymer solar modules by complementary imaging methods

    DEFF Research Database (Denmark)

    Rösch, R.; Krebs, Frederik C; Tanenbaum, D.M.

    2012-01-01

    We applied complementary imaging methods to investigate processing failures of roll-to-roll solution processed polymer solar modules based on polymer:fullerene bulk heterojunctions. For investigation of processing deficiencies in solar modules we employed dark lock-in thermography (DLIT......), electroluminescence (ELI) and photoluminescence/reflection imaging (PLI/RI) complemented by optical imaging (OI). The combination of all high resolution images allowed us to allocate the origin of processing errors to a specific deposition process, i.e. the insufficient coverage of an electrode interlayer...

  13. Disease Control After Reduced Volume Conformal and Intensity Modulated Radiation Therapy for Childhood Craniopharyngioma

    Energy Technology Data Exchange (ETDEWEB)

    Merchant, Thomas E., E-mail: thomas.merchant@stjude.org [St Jude Children' s Research Hospital, Radiological Sciences, Memphis, Tennessee (United States); Kun, Larry E.; Hua, Chia-Ho [St Jude Children' s Research Hospital, Radiological Sciences, Memphis, Tennessee (United States); Wu, Shengjie; Xiong, Xiaoping [St Jude Children' s Research Hospital, Biostatistics, Memphis, Tennessee (United States); Sanford, Robert A.; Boop, Frederick A. [Semmes Murphey Neurologic and Spine Institute, Neurosurgery, Memphis, Tennessee (United States)

    2013-03-15

    Purpose: To estimate the rate of disease control after conformal radiation therapy using reduced clinical target volume (CTV) margins and to determine factors that predict for tumor progression. Methods and Materials: Eighty-eight children (median age, 8.5 years; range, 3.2-17.6 years) received conformal or intensity modulated radiation therapy between 1998 and 2009. The study group included those prospectively treated from 1998 to 2003, using a 10-mm CTV, defined as the margin surrounding the solid and cystic tumor targeted to receive the prescription dose of 54 Gy. The CTV margin was subsequently reduced after 2003, yielding 2 groups of patients: those treated with a CTV margin greater than 5 mm (n=26) and those treated with a CTV margin less than or equal to 5 mm (n=62). Disease progression was estimated on the basis of additional variables including sex, race, extent of resection, tumor interventions, target volume margins, and frequency of weekly surveillance magnetic resonance (MR) imaging during radiation therapy. Median follow-up was 5 years. Results: There was no difference between progression-free survival rates based on CTV margins (>5 mm vs ≤5 mm) at 5 years (88.1% ± 6.3% vs 96.2% ± 4.4% [P=.6386]). There were no differences based on planning target volume (PTV) margins (or combined CTV plus PTV margins). The PTV was systematically reduced from 5 to 3 mm during the time period of the study. Factors predictive of superior progression-free survival included Caucasian race (P=.0175), no requirement for cerebrospinal fluid shunting (P=.0066), and number of surveillance imaging studies during treatment (P=.0216). Patients whose treatment protocol included a higher number of weekly surveillance MR imaging evaluations had a lower rate of tumor progression. Conclusions: These results suggest that targeted volume reductions for radiation therapy using smaller margins are feasible and safe but require careful monitoring. We are currently investigating

  14. Role of Modulators in Controlling the Colloidal Stability and Polydispersity of the UiO-66 Metal–Organic Framework

    Energy Technology Data Exchange (ETDEWEB)

    Morris, William; Wang, Shunzhi; Cho, David; Auyeung, Evelyn; Li, Peng; Farha, Omar K.; Mirkin, Chad A. (King Abdulaziz); (NWU)

    2017-04-07

    Nanoscale UiO-66 Zr6(OH)4O4(C8O4H4)6 has been synthesized with a series of carboxylic acid modulators, R-COOH (where R = H, CH3, CF3, and CHCl2). The phase purity and size of each MOF was confirmed by powder X-ray diffraction, BET surface area analysis, and scanning transmission electron microscopy (STEM). Size control of UiO-66 crystals from 20 nm to over 1 μm was achieved, and confirmed by STEM. The colloidal stability of each MOF was evaluated by dynamic light scattering and was found to be highly dependent on the modulator conditions utilized in the synthesis, with both lower pKa and higher acid concentration resulting in more stable structures. Furthermore, STEM was carried out on both colloidally stable samples and those that exhibited a large degree of aggregation, which allowed for visualization of the different degrees of dispersion of the samples. The use of modulators at higher concentrations and with lower pKas leads to the formation of more defects, as a consequence of terephthalic acid ligands being replaced by modulator molecules, thereby enhancing the colloidal stability of the UiO-66 nanoparticles. These findings could have a significant impact on nanoscale MOF material syntheses and applications, especially in the areas of catalysis and drug delivery.

  15. Distributed control of PV strings with module integrated converters in presence of a central MPPT

    DEFF Research Database (Denmark)

    Sera, Dezso; Mathe, Laszlo; Blaabjerg, Frede

    2014-01-01

    In some cases it is unavoidable that part of the rooftop PV array is periodically shadowed by an adjacent object, greatly reducing yield. Usually, the time and amount of shadowing is known, and is considered as extra loss due to the location. Module Integrated Converter (MIC) systems are known...

  16. Frontal eye fields control attentional modulation of alpha and gamma oscillations in contralateral occipitoparietal cortex

    NARCIS (Netherlands)

    Marshall, T.R.; O'Shea, J.; Jensen, O.; Bergmann, T.O.

    2015-01-01

    Covertly directing visuospatial attention produces a frequency-specific modulation of neuronal oscillations in occipital and parietal cortices: anticipatory alpha (8-12 Hz) power decreases contralateral and increases ipsilateral to attention, whereas stimulus-induced gamma (>40 Hz) power is boosted

  17. Using periodic modulation to control coexisting attractors induced by delayed feedback

    International Nuclear Information System (INIS)

    Martinez-Zerega, B.E.; Pisarchik, A.N.; Tsimring, L.S.

    2003-01-01

    A delay in feedback can stabilize simultaneously several unstable periodic orbits embedded in a chaotic attractor. We show that by modulating the feedback variable it is possible to lock one of these states and eliminate other coexisting periodic attractors. The method is demonstrated with both a logistic map and a CO 2 laser model

  18. Threat/reward-sensitivity and hypomanic-personality modulate cognitive-control and attentional neural processes to emotional stimuli.

    Science.gov (United States)

    Pornpattananangkul, Narun; Hu, Xiaoqing; Nusslock, Robin

    2015-11-01

    Temperamental-traits (e.g. threat/reward-sensitivity) are found to modulate cognitive-control and attentional-processes. Yet, it is unclear exactly how these traits interact with emotional-stimuli in the modulation of cognitive-control, as reflected by the N2 event-related potential (ERP), and attentional-processes, as reflected by the P2 and P3 ERPs. Here in an ERP emotional-Go/NoGo task, 36 participants were instructed to inhibit their response to Fearful- and Happy-faces. Individual-differences in threat-sensitivity, reward-sensitivity and hypomanic-personality were assessed through self-report. Hypomanic-personality was assessed, given its relationship with reward-sensitivity and relevance to mood-disorder symptoms. Concerning cognitive-control, individuals with elevated threat-sensitivity displayed more-negative N2s to Happy-NoGo (relative to Fearful-NoGo) faces, whereas both individuals with elevated reward-sensitivity and hypomanic-personality displayed more-negative N2s to Fearful-NoGo (relative to Happy-NoGo) faces. Accordingly, when cognitive-control is required (during Go/NoGo), a mismatch between one's temperament and the valence of the NoGo-stimulus elevates detection of the need for cognitive-control. Conversely, the modulation of attentional-processing was specific to threat-sensitivity, as there was no relationship between either reward-sensitivity or hypomanic-personality and attentional-processing. Elevated threat-sensitivity was associated with enhanced early (P2s) and later (P3s) attentional-processing to Fearful-NoGo (relative to Happy-NoGo) faces. These latter findings support the negative attentional-bias model relating elevated threat-sensitivity with attentional-biases toward negative-stimuli and away from positive-stimuli. © The Author (2015). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  19. Real-time line-width measurements: a new feature for reticle inspection systems

    Science.gov (United States)

    Eran, Yair; Greenberg, Gad; Joseph, Amnon; Lustig, Cornel; Mizrahi, Eyal

    1997-07-01

    The significance of line width control in mask production has become greater with the lessening of defect size. There are two conventional methods used for controlling line widths dimensions which employed in the manufacturing of masks for sub micron devices. These two methods are the critical dimensions (CD) measurement and the detection of edge defects. Achieving reliable and accurate control of line width errors is one of the most challenging tasks in mask production. Neither of the two methods cited above (namely CD measurement and the detection of edge defects) guarantees the detection of line width errors with good sensitivity over the whole mask area. This stems from the fact that CD measurement provides only statistical data on the mask features whereas applying edge defect detection method checks defects on each edge by itself, and does not supply information on the combined result of error detection on two adjacent edges. For example, a combination of a small edge defect together with a CD non- uniformity which are both within the allowed tolerance, may yield a significant line width error, which will not be detected using the conventional methods (see figure 1). A new approach for the detection of line width errors which overcomes this difficulty is presented. Based on this approach, a new sensitive line width error detector was developed and added to Orbot's RT-8000 die-to-database reticle inspection system. This innovative detector operates continuously during the mask inspection process and scans (inspects) the entire area of the reticle for line width errors. The detection is based on a comparison of measured line width that are taken on both the design database and the scanned image of the reticle. In section 2, the motivation for developing this new detector is presented. The section covers an analysis of various defect types, which are difficult to detect using conventional edge detection methods or, alternatively, CD measurements. In section 3

  20. Emergency Victim Care. A Training Manual for Emergency Medical Technicians. Module 2. Equipment, Safe Driving Practices, Legal Aspects, Controlling the Situation, Action Evaluation Conference. Revised.

    Science.gov (United States)

    Ohio State Dept. of Education, Columbus. Div. of Vocational Education.

    This student manual, the second in a set of 14 modules, is designed to train emergency medical technicians (EMTs) in Ohio. The module contains five sections that cover the following course content: ambulance equipment, safe driving practices for emergency vehicle drivers, legal aspects of the EMT's job, how to maintain control at an accident scene…

  1. Evolution and diversity of subduction zones controlled by slab width

    NARCIS (Netherlands)

    Schellart, W. P.; Freeman, J.A.; Stegman, D. R.; Moresi, L.; May, D.

    2007-01-01

    Subducting slabs provide the main driving force for plate motion and flow in the Earth's mantle, and geodynamic, seismic and geochemical studies offer insight into slab dynamics and subduction-induced flow. Most previous geodynamic studies treat subduction zones as either infinite in trench-parallel

  2. Effects of Stress and Relaxation on Central Pain Modulation in Chronic Whiplash and Fibromyalgia Patients Compared to Healthy Controls.

    Science.gov (United States)

    Coppieters, Iris; Cagnie, Barbara; Nijs, Jo; van Oosterwijck, Jessica; Danneels, Lieven; De Pauw, Robby; Meeus, Mira

    2016-03-01

    Compelling evidence has demonstrated that impaired central pain modulation contributes to persistent pain in patients with chronic whiplash associated disorders (WAD) and fibromyalgia (FM). However, there is limited research concerning the influence of stress and relaxation on central pain modulation in patients with chronic WAD and FM. The present study aims to investigate the effects of acute cognitive stress and relaxation on central pain modulation in chronic WAD and FM patients compared to healthy individuals. A randomized crossover design was employed. The present study took place at the University of Brussels, the University Hospital Brussels, and the University of Antwerp. Fifty-nine participants (16 chronic WAD patients, 21 FM, 22 pain-free controls) were enrolled and subjected to various pain measurements. Temporal summation (TS) of pain and conditioned pain modulation (CPM) were evaluated. Subsequently, participants were randomly allocated to either a group that received progressive relaxation therapy or a group that performed a battery of cognitive tests (= cognitive stressor). Afterwards, all pain measurements were repeated. One week later participant groups were switched. A significant difference was found between the groups in the change in TS in response to relaxation (P = 0.008) and cognitive stress (P = 0.003). TS decreased in response to relaxation and cognitive stress in chronic WAD patients and controls. In contrast, TS increased after both interventions in FM patients. CPM efficacy decreased in all 3 groups in response to relaxation (P = 0.002) and cognitive stress (P = 0.001). The obtained results only apply for a single session of muscle relaxation therapy and cognitive stress, whereby no conclusions can be made for effects on pain perception and modulation of chronic cognitive stress and long-term relaxation therapies. A single relaxation session as well as cognitive stress may have negative acute effects on pain modulation in patients with

  3. Locoregional control after intensity-modulated radiotherapy for nasopharyngeal carcinoma with an anatomy-based target definition

    International Nuclear Information System (INIS)

    Kawashima, Mitsuhiko; Ariji, Takaki; Kameoka, Satoru

    2013-01-01

    The objective of the study was to evaluate locoregional control after intensity-modulated radiotherapy for nasopharyngeal cancer using a target definition along with anatomical boundaries. Forty patients with biopsy-proven squamous cell or non-keratinizing carcinoma of the nasopharynx who underwent intensity-modulated radiotherapy between April 2006 and November 2009 were reviewed. There were 10 females and 30 males with a median age of 48 years (range, 17-74 years). More than half of the patients had T3/4 (n=21) and/or N2/3 (n=24) disease. Intensity-modulated radiotherapy was administered as 70 Gy/33 fractions with or without concomitant chemotherapy. The clinical target volume was contoured along with muscular fascia or periosteum, and the prescribed radiotherapy dose was determined for each anatomical compartment and lymph node level in the head and neck. One local recurrence was observed at Meckel's cave on the periphery of the high-risk clinical target volume receiving a total dose of <63 Gy. Otherwise, six locoregional failures were observed within irradiated volume receiving 70 Gy. Local and nodal control rates at 3 years were 91 and 89%, respectively. Adverse events were acceptable, and 25 (81%) of 31 patients who were alive without recurrence at 2 years had xerostomia of ≤ Grade 1. The overall survival rate at 3 years was 87%. Target definition along with anatomically defined boundaries was feasible without compromise of the therapeutic ratio. It is worth testing this method further to minimize the unnecessary irradiated volume and to standardize the target definition in intensity-modulated radiotherapy for nasopharyngeal cancer. (author)

  4. The significance of biometric parameters in determining anterior teeth width

    Directory of Open Access Journals (Sweden)

    Strajnić Ljiljana

    2013-01-01

    Full Text Available Background/Aim. An important element of prosthetic treatment of edentulous patients is selecting the size of anterior artificial teeth that will restore the natural harmony of one’s dentolabial structure as well as the whole face. The main objective of this study was to determine the correlation between the inner canthal distance (ICD and interalar width (IAW on one side and the width of both central incisors (CIW, the width of central and lateral incisors (CLIW, the width of anterior teeth (ATW, the width between the canine cusps (CCW, which may be useful in clinical practice. Methods. A total of 89 subjects comprising 23 male and 66 female were studied. Their age ranged from 19 to 34 years with the mean of 25 years. Only the subjects with the preserved natural dentition were included in the sample. All facial and intraoral tooth measurements were made with a Boley Gauge (Buffalo Dental Manufacturing Co., Brooklyn NY, USA having a resolution of 0.1mm. Results. A moderate correlation was established between the interalar width and combined width of anterior teeth and canine cusp width (r = 0.439, r = 0.374. A low correlation was established between the inner canthal distance and the width of anterior teeth and canine cusp width (r = 0.335, r = 0.303. The differences between the two genders were highly significant for all the parameters (p < 0.01. The measured facial distances and width of anterior teeth were higher in men than in women. Conclusion. The results of this study suggest that the examined interalar width and inner canthal distance cannot be considered reliable guidelines in the selection of artificial upper anterior teeth. However, they may be used as a useful additional factor combined with other methods for objective tooth selection. The final decision should be made while working on dentures fitting models with the patient’s consent.

  5. Substance P Differentially Modulates Firing Rate of Solitary Complex (SC) Neurons from Control and Chronic Hypoxia-Adapted Adult Rats

    Science.gov (United States)

    Nichols, Nicole L.; Powell, Frank L.; Dean, Jay B.; Putnam, Robert W.

    2014-01-01

    NK1 receptors, which bind substance P, are present in the majority of brainstem regions that contain CO2/H+-sensitive neurons that play a role in central chemosensitivity. However, the effect of substance P on the chemosensitive response of neurons from these regions has not been studied. Hypoxia increases substance P release from peripheral afferents that terminate in the caudal nucleus tractus solitarius (NTS). Here we studied the effect of substance P on the chemosensitive responses of solitary complex (SC: NTS and dorsal motor nucleus) neurons from control and chronic hypoxia-adapted (CHx) adult rats. We simultaneously measured intracellular pH and electrical responses to hypercapnic acidosis in SC neurons from control and CHx adult rats using the blind whole cell patch clamp technique and fluorescence imaging microscopy. Substance P significantly increased the basal firing rate in SC neurons from control and CHx rats, although the increase was smaller in CHx rats. However, substance P did not affect the chemosensitive response of SC neurons from either group of rats. In conclusion, we found that substance P plays a role in modulating the basal firing rate of SC neurons but the magnitude of the effect is smaller for SC neurons from CHx adult rats, implying that NK1 receptors may be down regulated in CHx adult rats. Substance P does not appear to play a role in modulating the firing rate response to hypercapnic acidosis of SC neurons from either control or CHx adult rats. PMID:24516602

  6. Substance P differentially modulates firing rate of solitary complex (SC neurons from control and chronic hypoxia-adapted adult rats.

    Directory of Open Access Journals (Sweden)

    Nicole L Nichols

    Full Text Available NK1 receptors, which bind substance P, are present in the majority of brainstem regions that contain CO2/H(+-sensitive neurons that play a role in central chemosensitivity. However, the effect of substance P on the chemosensitive response of neurons from these regions has not been studied. Hypoxia increases substance P release from peripheral afferents that terminate in the caudal nucleus tractus solitarius (NTS. Here we studied the effect of substance P on the chemosensitive responses of solitary complex (SC: NTS and dorsal motor nucleus neurons from control and chronic hypoxia-adapted (CHx adult rats. We simultaneously measured intracellular pH and electrical responses to hypercapnic acidosis in SC neurons from control and CHx adult rats using the blind whole cell patch clamp technique and fluorescence imaging microscopy. Substance P significantly increased the basal firing rate in SC neurons from control and CHx rats, although the increase was smaller in CHx rats. However, substance P did not affect the chemosensitive response of SC neurons from either group of rats. In conclusion, we found that substance P plays a role in modulating the basal firing rate of SC neurons but the magnitude of the effect is smaller for SC neurons from CHx adult rats, implying that NK1 receptors may be down regulated in CHx adult rats. Substance P does not appear to play a role in modulating the firing rate response to hypercapnic acidosis of SC neurons from either control or CHx adult rats.

  7. Modulation of Protein Quality Control and Proteasome to Autophagy Switch in Immortalized Myoblasts from Duchenne Muscular Dystrophy Patients

    Directory of Open Access Journals (Sweden)

    Marion Wattin

    2018-01-01

    Full Text Available The maintenance of proteome integrity is of primary importance in post-mitotic tissues such as muscle cells; thus, protein quality control mechanisms must be carefully regulated to ensure their optimal efficiency, a failure of these processes being associated with various muscular disorders. Duchenne muscular dystrophy (DMD is one of the most common and severe forms of muscular dystrophies and is caused by mutations in the dystrophin gene. Protein quality control modulations have been diversely observed in degenerating muscles of patients suffering from DMD or in animal models of the disease. In this study, we investigated whether modulations of protein quality control mechanisms already pre-exist in undifferentiated myoblasts originating from DMD patients. We report for the first time that the absence of dystrophin in human myoblasts is associated with protein aggregation stress characterized by an increase of protein aggregates. This stress is combined with BAG1 to BAG3 switch, NFκB activation and up-regulation of BAG3/HSPB8 complexes that ensure preferential routing of misfolded/aggregated proteins to autophagy rather than to deficient 26S proteasome. In this context, restoration of pre-existing alterations of protein quality control processes might represent an alternative strategy for DMD therapies.

  8. An attempt at MHD mode control by feedback modulation of L.H. driven current

    International Nuclear Information System (INIS)

    Parlange, F.; Vallet, J.C

    1986-01-01

    MHD activity in Tokamak discharges with lower hybrid current drive has distinct features which can be used to stabilize tearing modes. A way of reducing the m=2 tearing mode was recently proposed, consisting in driving more current at the 0 point of the islands than at the X point, by means of amplitude modulated lower hybrid waves. The way it was tested in Petula is presented here

  9. Controlled Enhancemnt of Long-Term Memory by Modulating Neuronal miRNA Function

    Science.gov (United States)

    2012-09-20

    Faraday Ave. Carlsbad CA 92008 Prepare antisense oligonucleotides 8/1/2007 12:00:00AM 2/1/2009 12:00:00AM Sub Contractor Numbers (c): Patent Clause...with ampakines. However, ampakines that accomplish positive modulation have shown undesired clinical side effects . Another approach is to improve...of times that a mouse touches objects introduced into the cage in a fixed period of time. Objects are either “old” (prior exposure) or “new” (not

  10. Smart Global Maximum Power Point Tracking Controller of Photovoltaic Module Arrays

    Directory of Open Access Journals (Sweden)

    Long-Yi Chang

    2018-03-01

    Full Text Available This study first explored the effect of shading on the output characteristics of modules in a photovoltaic module array. Next, a modified particle swarm optimization (PSO method was employed to track the maximum power point of the multiple-peak characteristic curve of the array. Through the optimization method, the weighting value and cognition learning factor decreased with an increasing number of iterations, whereas the social learning factor increased, thereby enhancing the tracking capability of a maximum power point tracker. In addition, the weighting value was slightly modified on the basis of the changes in the slope and power of the characteristic curve to increase the tracking speed and stability of the tracker. Finally, a PIC18F8720 microcontroller was coordinated with peripheral hardware circuits to realize the proposed PSO method, which was then adopted to track the maximum power point of the power–voltage (P–V output characteristic curve of the photovoltaic module array under shading. Subsequently, tests were conducted to verify that the modified PSO method exhibited favorable tracking speed and accuracy.

  11. Step width alters iliotibial band strain during running.

    Science.gov (United States)

    Meardon, Stacey A; Campbell, Samuel; Derrick, Timothy R

    2012-11-01

    This study assessed the effect of step width during running on factors related to iliotibial band (ITB) syndrome. Three-dimensional (3D) kinematics and kinetics were recorded from 15 healthy recreational runners during overground running under various step width conditions (preferred and at least +/- 5% of their leg length). Strain and strain rate were estimated from a musculoskeletal model of the lower extremity. Greater ITB strain and strain rate were found in the narrower step width condition (p running, especially in persons whose running style is characterized by a narrow step width, may be beneficial in the treatment and prevention of running-related ITB syndrome.

  12. A water pumping control system with a programmable logic controller (PLC) and industrial wireless modules for industrial plants--an experimental setup.

    Science.gov (United States)

    Bayindir, Ramazan; Cetinceviz, Yucel

    2011-04-01

    This paper describes a water pumping control system that is designed for production plants and implemented in an experimental setup in a laboratory. These plants contain harsh environments in which chemicals, vibrations or moving parts exist that could potentially damage the cabling or wires that are part of the control system. Furthermore, the data has to be transferred over paths that are accessible to the public. The control systems that it uses are a programmable logic controller (PLC) and industrial wireless local area network (IWLAN) technologies. It is implemented by a PLC, an communication processor (CP), two IWLAN modules, and a distributed input/output (I/O) module, as well as the water pump and sensors. Our system communication is based on an Industrial Ethernet and uses the standard Transport Control Protocol/Internet Protocol for parameterisation, configuration and diagnostics. The main function of the PLC is to send a digital signal to the water pump to turn it on or off, based on the tank level, using a pressure transmitter and inputs from limit switches that indicate the level of the water in the tank. This paper aims to provide a convenient solution in process plants where cabling is not possible. It also has lower installation and maintenance cost, provides reliable operation, and robust and flexible construction, suitable for industrial applications. Copyright © 2010 ISA. Published by Elsevier Ltd. All rights reserved.

  13. Comparison of the equivalent width, the autocorrelation width, and the variance as figures of merit for XPS narrow scans

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Bhupinder [Department of Chemistry and Biochemistry, C-100 BNSN, Brigham Young University, Provo, UT 84602 (United States); Velázquez, Daniel; Terry, Jeff [Department of Physics, Illinois Institute of Technology, Chicago, IL 60616 (United States); Linford, Matthew R., E-mail: mrlinford@chem.byu.edu [Department of Chemistry and Biochemistry, C-100 BNSN, Brigham Young University, Provo, UT 84602 (United States)

    2014-12-15

    Highlights: • We apply the equivalent and autocorrelation widths and variance to XPS narrow scans. • This approach is complementary to traditional peak fitting methods. • It is bias free and responsive to subtle chemical changes in spectra. • It has the potential for machine interpretation of spectra and quality control. • It has the potential for analysis of complex spectra and tracking charging/artifacts. - Abstract: X-ray photoelectron spectroscopy (XPS) is widely used in surface and materials laboratories around the world. It is a near surface technique, providing detailed chemical information about samples in the form of survey and narrow scans. To extract the maximum amount of information about materials it is often necessary to peak fit XPS narrow scans. And while indispensable to XPS data analysis, even experienced practitioners can struggle with their peak fitting. In our previous publication, we introduced the equivalent width (EW{sub XPS}) as both a possible machine automated method, one that requires less expert judgment for characterizing XPS narrow scans, and as an approach that may be well suited for the analysis of complex spectra. The EW{sub XPS} figure of merit was applied to four different data sets. However, as previously noted, other width functions are also regularly employed for analyzing functions. Here we evaluate two other width functions for XPS narrow scan analysis: the autocorrelation width (AW{sub XPS}) and the variance (σ{sub XPS}{sup 2}). These widths were applied to the same four sets of spectra studied before: (a) four C 1s narrow scans of ozone-treated carbon nanotubes (CNTs) (EW{sub XPS}: ∼2.11–2.16 eV, AW{sub XPS}: ∼3.9–4.1 eV, σ{sub XPS}{sup 2}: ∼5.0–5.2 eV, and a modified form of σ{sub XPS}{sup 2}, denoted σ{sub XPS}{sup 2*}: ∼6.3–6.8 eV), (b) silicon wafers with different oxide thicknesses (EW{sub XPS}: ∼1.5–2.9 eV, AW{sub XPS}: ∼2.28–4.9, and σ{sub XPS}{sup 2}: ∼0.7–4.9 eV), (iii

  14. Extending the Linear Modulation Range to the Full Base Speed Using a Single DC-Link Multilevel Inverter With Capacitor-Fed H-Bridges for IM Drives

    DEFF Research Database (Denmark)

    Rahul, Arun; Pramanick, Sumit; Kaarthik, R. Sudharshan

    2017-01-01

    In this paper, a new space vector pulse width modulation method to extend the linear modulation range of a cascaded five level inverter topology with a single dc supply is presented. Using this method, the inverter can be controlled linearly and the peak phase fundamental output voltage of the in......In this paper, a new space vector pulse width modulation method to extend the linear modulation range of a cascaded five level inverter topology with a single dc supply is presented. Using this method, the inverter can be controlled linearly and the peak phase fundamental output voltage...... of the inverter can be increased from 0.577 to 0.637Vdc without increasing the dc bus voltage and without exceeding the induction motor voltage rating. This new technique makes use of cascaded inverter pole voltage redundancy and property of the space vector structure for its operation. Using this, the induction...

  15. Bulimia nervosa: mood changes do have an impact on body width estimation.

    Science.gov (United States)

    Kulbartz-Klatt, Y J; Florin, I; Pook, M

    1999-09-01

    This study was designed to investigate the impact of mood changes on body width estimation in women with bulimia nervosa. A pre-post controlled experimental design was chosen. Mood changes were induced in 40 women with bulimia nervosa, 20 women with panic disorder and 40 women with no diagnosis of a psychological disorder. A combination of autobiographical memory method and music induction method was used to induce positive and negative mood, respectively. Before and after mood induction a video distorting technique was used for body width estimation. Induction of negative mood increased and induction of positive mood decreased the body width estimations of women with bulimia. Patients with panic disorder and 'healthy' controls did not show these changes after mood induction. The findings suggest that change in mood state rather than the more habitual mood quality are relevant for bulimic women's body perception.

  16. SCALE: A modular code system for performing standardized computer analyses for licensing evaluation. Control modules -- Volume 1, Revision 4

    Energy Technology Data Exchange (ETDEWEB)

    Landers, N.F.; Petrie, L.M.; Knight, J.R. [Oak Ridge National Lab., TN (United States)] [and others

    1995-04-01

    SCALE--a modular code system for Standardized Computer Analyses Licensing Evaluation--has been developed by Oak Ridge National Laboratory at the request of the US Nuclear Regulatory Commission. The SCALE system utilizes well-established computer codes and methods within standard analysis sequences that (1) allow an input format designed for the occasional user and/or novice, (2) automate the data processing and coupling between modules, and (3) provide accurate and reliable results. System development has been directed at problem-dependent cross-section processing and analysis of criticality safety, shielding, heat transfer, and depletion/decay problems. Since the initial release of SCALE in 1980, the code system has been heavily used for evaluation of nuclear fuel facility and package designs. This revision documents Version 4.2 of the system. This manual is divided into three volumes: Volume 1--for the control module documentation, Volume 2--for the functional module documentation, and Volume 3 for the documentation of the data libraries and subroutine libraries.

  17. SCALE: A modular code system for performing standardized computer analyses for licensing evaluation. Control modules -- Volume 1, Revision 4

    International Nuclear Information System (INIS)

    Landers, N.F.; Petrie, L.M.; Knight, J.R.

    1995-04-01

    SCALE--a modular code system for Standardized Computer Analyses Licensing Evaluation--has been developed by Oak Ridge National Laboratory at the request of the US Nuclear Regulatory Commission. The SCALE system utilizes well-established computer codes and methods within standard analysis sequences that (1) allow an input format designed for the occasional user and/or novice, (2) automate the data processing and coupling between modules, and (3) provide accurate and reliable results. System development has been directed at problem-dependent cross-section processing and analysis of criticality safety, shielding, heat transfer, and depletion/decay problems. Since the initial release of SCALE in 1980, the code system has been heavily used for evaluation of nuclear fuel facility and package designs. This revision documents Version 4.2 of the system. This manual is divided into three volumes: Volume 1--for the control module documentation, Volume 2--for the functional module documentation, and Volume 3 for the documentation of the data libraries and subroutine libraries

  18. Counterfactual reasoning for regretted situations involving controllable versus uncontrollable events: the modulating role of contingent self-esteem.

    Science.gov (United States)

    Wilkinson, Meredith R; Ball, Linden J; Alford, David

    2015-01-01

    We report a study that examined the modulating impact of contingent self-esteem on regret intensity for regretted outcomes associated with controllable versus uncontrollable events. The Contingent Self-Esteem Scale (e.g., Kernis & Goldman, 2006) was used to assess the extent to which a person's sense of self-worth is based on self and others' expectations. We found that there was an influence of self-esteem contingency for controllable but not for uncontrollable regret types. For controllable regret types individuals with a high contingent (i.e., unstable) self-esteem reported greater regret intensity than those with a low contingent (i.e., stable) self-esteem. We interpret this finding as reflecting a functional and adaptive role of high contingent self-esteem in terms of mobilizing the application of counterfactual reasoning and planning mechanisms that can enable personal expectations to be achieved in the future.

  19. Counterfactual Reasoning for Regretted Situations Involving Controllable Versus Uncontrollable Events: The Modulating Role of Contingent Self-Esteem

    Science.gov (United States)

    Wilkinson, Meredith R.; Ball, Linden J.; Alford, David

    2015-01-01

    We report a study that examined the modulating impact of contingent self-esteem on regret intensity for regretted outcomes associated with controllable versus uncontrollable events. The Contingent Self-Esteem Scale (e.g., Kernis & Goldman, 2006) was used to assess the extent to which a person’s sense of self-worth is based on self and others’ expectations. We found that there was an influence of self-esteem contingency for controllable but not for uncontrollable regret types. For controllable regret types individuals with a high contingent (i.e., unstable) self-esteem reported greater regret intensity than those with a low contingent (i.e., stable) self-esteem. We interpret this finding as reflecting a functional and adaptive role of high contingent self-esteem in terms of mobilizing the application of counterfactual reasoning and planning mechanisms that can enable personal expectations to be achieved in the future. PMID:25883697

  20. Relationship between red cell distribution width and early renal injury in patients with gestational diabetes mellitus.

    Science.gov (United States)

    Cheng, Dong; Zhao, Jiangtao; Jian, Liguo; Ding, Tongbin; Liu, Shichao

    2016-09-01

    Previous studies found that red cell distribution width was related to adverse cardiovascular events. However, few studies reported the relationship between red cell distribution width and early-stage renal injury in pregnant women with gestational diabetes mellitus. Using a cross-sectional design, 334 pregnant women with gestational diabetes mellitus were enrolled according to the criterion of inclusion and exclusion. Demographic and clinical examination data were collected. Depended on the urine albumin, study population were divided into case group (n = 118) and control group (n = 216). Compared with control group, the case group tend to be higher red cell distribution width level (13.6 ± 0.9 vs.12.5 ± 0.6, p gestational diabetes mellitus patients. The elevated red cell distribution width level might be a predictor of early-stage renal injury in pregnant women with gestational diabetes mellitus. As an easy and routine examination index, red cell distribution width may provide better clinical guidance when combined with other important indices.