WorldWideScience

Sample records for automatic gain control

  1. Digital automatic gain control

    Science.gov (United States)

    Uzdy, Z.

    1980-01-01

    Performance analysis, used to evaluated fitness of several circuits to digital automatic gain control (AGC), indicates that digital integrator employing coherent amplitude detector (CAD) is best device suited for application. Circuit reduces gain error to half that of conventional analog AGC while making it possible to automatically modify response of receiver to match incoming signal conditions.

  2. Commutated automatic gain control system

    Science.gov (United States)

    Yost, S. R.

    1982-01-01

    The commutated automatic gain control (AGC) system was designed and built for the prototype Loran-C receiver is discussed. The current version of the prototype receiver, the Mini L-80, was tested initially in 1980. The receiver uses a super jolt microcomputer to control a memory aided phase loop (MAPLL). The microcomputer also controls the input/output, latitude/longitude conversion, and the recently added AGC system. The AGC control adjusts the level of each station signal, such that the early portion of each envelope rise is about at the same amplitude in the receiver envelope detector.

  3. Modeling of a Multiple Digital Automatic Gain Control System

    Institute of Scientific and Technical Information of China (English)

    WANG Jingdian; LU Xiuhong; ZHANG Li

    2008-01-01

    Automatic gain control (AGC) has been used in many applications. The key features of AGC, including a steady state output and static/dynamic timing response, depend mainly on key parameters such as the reference and the filter coefficients. A simple model developed to describe AGC systems based on several simple assumptions shows that AGC always converges to the reference and that the timing constant depends on the filter coefficients. Measures are given to prevent oscillations and limit cycle effects. The simple AGC system is adapted to a multiple AGC system for a TV tuner in a much more efficient model. Simulations using the C language are 16 times faster than those with MATLAB, and 10 times faster than those with a mixed register transfer level (RTL)-simulation program with integrated circuit emphasis (SPICE) model.

  4. An output amplitude configurable wideband automatic gain control with high gain step accuracy

    Institute of Scientific and Technical Information of China (English)

    何晓丰; 莫太山; 马成炎; 叶甜春

    2012-01-01

    An output amplitude configurable wideband automatic gain control (AGC) with high gain step accuracy for the GNSS receiver is presented.The amplitude of an AGC is configurable in order to cooperate with baseband chips to achieve interference suppression and be compatible with different full range ADCs.And what's more,the gain-boosting technology is introduced and the circuit is improved to increase the step accuracy.A zero,which is composed by the source feedback resistance and the source capacity,is introduced to compensate for the pole.The AGC is fabricated in a 0.18 μm CMOS process.The AGC shows a 62 dB gain control range by 1 dB each step with a gain error of less than 0.2 dB.The AGC provides 3 dB bandwidth larger than 80 MHz and the overall power consumption is less than 1.8 mA,and the die area is 800 × 300μm2.

  5. Development of an Automatic Gain Controller Card or Next Generation EDFAs

    Institute of Scientific and Technical Information of China (English)

    C. Y. Liaw; T. H. Cheng; C. Lu; M.Akiyama; T.Sakai; A.Wada

    2003-01-01

    This paper describes a low cost automatic gain controller card that provides fast transient gain control to maintain the power of the surviving channels when the number of input channels to an erbium-doped fiber amplifier (EDFA)changes rapidly.

  6. A novel analog/digital reconfigurable automatic gain control with a novel DC offset cancellation circuit*

    Institute of Scientific and Technical Information of China (English)

    He Xiaofeng; Mo Taishan; Ma Chengyan; Ye Tianchun

    2011-01-01

    An analog/digital reconfigurable automatic gain control (AGC) circuit with a novel DC offset cancellation circuit for a direct-conversion receiver is presented. The AGC is analog/digital reconfigurable in order to be compatible with different baseband chips. What's more, a novel DC offset cancellation (DCOC) circuit with an HPCF (high pass cutoff frequency) less than 10 kHz is proposed. The AGC is fabricated by a 0.18 μm CMOS process. Under analog control mode, the AGC achieves a 70 dB dynamic range with a 3 dB-bandwidth larger than 60 MHz. Under digital control mode, through a 5-bit digital control word, the AGC shows a 64 dB gain control range by 2 dB each step with a gain error of less than 0.3 dB. The DC offset cancellation circuits can suppress the output DC offset voltage to be less than 1.5 mV, while the offset voltage of 40 mV is introduced into the input. The overall power consumption is less than 3.5 mA, and the die area is 800 × 300μm2.

  7. SEMICONDUCTOR INTEGRATED CIRCUITS: A low power automatic gain control loop for a receiver

    Science.gov (United States)

    Guofeng, Li; Zhiqing, Geng; Nanjian, Wu

    2010-09-01

    This paper proposes a new structure to lower the power consumption of a variable gain amplifier (VGA) and keep the linearity of the VGA unchanged. The structure is used in a high rate amplitude-shift keying (ASK) based IF-stage. It includes an automatic gain control (AGC) loop and ASK demodulator. The AGC mainly consists of six-stage VGAs. The IF-stage is realized in 0.18 μm CMOS technology. The measurement results show that the power consumption of the whole system is very low. The system consumes 730 μA while operating at 1.8 V. The minimum ASK signal the system could detect is 0.7 mV (peak to peak amplitude).

  8. Single-beam water vapor detection system with automatic photoelectric conversion gain control

    Science.gov (United States)

    Zhu, C. G.; Chang, J.; Wang, P. P.; Wang, Q.; Wei, W.; Liu, Z.; Zhang, S. S.

    2014-11-01

    A single-beam optical sensor system with automatic photoelectric conversion gain control is proposed for doing high reliability water vapor detection under relatively rough environmental conditions. Comparing to a dual-beam system, it can distinguish the finer photocurrent variations caused by the optical power drift and provide timely compensation by automatically adjusting the photoelectric conversion gain. This system can be rarely affected by the optical power drift caused by fluctuating ambient temperature or variation of fiber bending loss. The deviation of the single-beam system is below 1.11% when photocurrent decays due to fiber bending loss for bending radius of 5 mm, which is obviously lower than the dual-beam system (8.82%). We also demonstrate the long-term stability of the single-beam system by monitoring a 660 ppm by volume (ppmv) water vapor sample continuously for 24 h. The maximum deviation of the measured concentration during the whole testing period does not exceed 10 ppmv. Experiments have shown that the new system features better reliability and is more apt for remote sensing application which is often subject to light transmission loss.

  9. Automatic Gain Control in Mass Spectrometry using a Jet Disrupter Electrode in an Electrodynamic Ion Funnel

    Energy Technology Data Exchange (ETDEWEB)

    Page, Jason S.; Bogdanov, Bogdan; Vilkov, Andrey N.; Prior, David C.; Buschbach, Michael A.; Tang, Keqi; Smith, Richard D.

    2005-02-01

    We report on the use of a jet disrupter electrode in an electrodynamic ion funnel as an electronic valve to regulate the intensity of the ion beam transmitted through the interface of a mass spectrometer in order to perform automatic gain control (AGC). The ion flux is determined by either directly detecting the ion current on the conductance limiting orifice of the ion funnel or using a short mass spectrometry acquisition. Based upon the ion flux intensity, the voltage of the jet disrupter is adjusted to alter the transmission efficiency of the ion funnel to provide a desired ion population to the mass analyzer. Ion beam regulation by an ion funnel is shown to provide an unbiased control to within a few percent of a targeted ion intensity or abundance. The utility of ion funnel AGC was evaluated using a protein tryptic digest analyzed with liquid chromatography Fourier transform ion cyclotron resonance (LC-FTICR) mass spectrometry. The ion population in the ICR cell was accurately controlled to a variety of different levels, which improved data quality and provided better mass measurement accuracy.

  10. A digitally calibrated CMOS RMS power detector for RF automatic gain control

    Institute of Scientific and Technical Information of China (English)

    Yan Taotao; Wang Hui; Li Jinbo; Zhou Jianjun

    2013-01-01

    This paper presents the design and implementation of a digitally calibrated CMOS wideband radio frequency (RF) root-mean-square (RMS) power detector for high accuracy RF automatic gain control (AGC).The proposed RMS power detector demonstrates accurate power detection in the presence of process,supply voltage,and temperature (PVT) variations by employing a digital calibration scheme.It also consumes low power and occupies a small chip area.The measurement results show that the scheme improves the accuracy of the detector to better than 0.3 dB over the PVT variations and wide operating frequency range from 0.2 to 0.8 GHz.Implemented in a 0.18 μm CMOS process and occupying a small die area of 263 × 214 μm2,the proposed digitally calibrated CMOS RMS power detector only consumes 1.6 mA in power detection mode and 2.1 mA in digital calibration mode from a 1.8 V supply voltage.

  11. Design and performance of an Automatic Gain Control system for the High Energy X-Ray Timing Experiment

    Science.gov (United States)

    Pelling, Michael R.; Rothschild, Richard E.; Macdonald, Daniel R.; Hertel, Robert; Nishiie, Edward

    1991-01-01

    The High Energy X-Ray Timing Experiment (HEXTE), currently under development for the X-Ray Timing Explorer (XTE) mission, employs a closed loop gain control system to attain 0.5 percent stabilization of each of eight-phoswich detector gains. This Automatic Gain Control (AGC) system utilizes a split window discriminator scheme to control the response of each detector pulse height analyzer to gated Am-241 X-ray events at 60 keV. A prototype AGC system has been implemented and tested within the gain perturbation environment expected to be experienced by the HEXTE instrument in flight. The AGC system and test configuration are described. Response, stability and noise characteristics are measured and compared with theoretical predictions. The system is found to be generally suitable for the HEXTE application.

  12. Decision-directed automatic gain control for MAPSK systems. [M-ary Amplitude and Phase Shift Keying

    Science.gov (United States)

    Weber, W. J., III

    1974-01-01

    An automatic gain control (AGC) loop is presented for use with M-ary amplitude and phase shift keying (MAPSK) systems. The gain control amplifier is regulated by an error signal formed by the difference between the estimated amplitude level and the received amplitude level. The AGC performance is thus independent of the short-term average received signal energy. AGC loop analysis and simulation is presented for M-ary amplitude shift keying and quadrature amplitude shift keying. The AGC is shown to have a negligible degradation on the symbol probability of error for most practical cases. A generalized AGC for an arbitrary MAPSK system is presented.

  13. Gaining control

    NARCIS (Netherlands)

    Enden, van der E.; Laan, van der R.

    2008-01-01

    The article reports on the efforts of companies to find a solution for tax risk management, tax accounting and being in control. In trying to find a solution, companies work towards an integrated tax control framework (TCF), a tax risk management and control environment embedded in the internal cont

  14. Comparison of dual-time-constant and fast-acting automatic gain control (AGC) systems in cochlear implants.

    Science.gov (United States)

    Boyle, Patrick J; Büchner, Andreas; Stone, Michael A; Lenarz, Thomas; Moore, Brian C J

    2009-04-01

    Cochlear implants usually employ an automatic gain control (AGC) system as a first stage of processing. AGC1 was a fast-acting (syllabic) compressor. AGC2 was a dual-time-constant system; it usually performed as a slow-acting compressor, but incorporated an additional fast-acting system to provide protection from sudden increases in sound level. Six experienced cochlear-implant users were tested in a counterbalanced order, receiving one-month of experience with a given AGC type before switching to the other type. Performance was evaluated shortly after provision of a given AGC type and after one-month of experience with that AGC type. Questionnaires, mainly relating to listening in quiet situations, did not reveal significant differences between the two AGC types. However, fixed-level and roving-level tests of sentence identification in noise both revealed significantly better performance for AGC2. It is suggested that the poorer performance for AGC1 occurred because AGC1 introduced cross-modulation between the target speech and background noise, which made perceptual separation of the target and background more difficult.

  15. L-band automatic-gain-controlled erbium-doped fiber amplifier utilizing C-band backward-amplified spontaneous emission and electrical feedback monitor.

    Science.gov (United States)

    Shen, Jyi-Lai; Lee, Yueh-Chien; Huang, Chia-Chih

    2009-02-10

    A new L-band automatic-gain-controlled (AGC) erbium-doped fiber amplifier (EDFA) for dense wavelength-division-multiplexing transmission systems is presented, in which a single 1480 nm laser with an internal thermoelectric cooler is used as a primary pump for stable amplification. All C-band amplified spontaneous emission (ASE) is recycled by the secondary pump to enhance the gain efficiency. A fraction of the output signal is used as an electrical feedback monitor for the AGC to improve the gain-clamped (GC) flatness. Experimental results prove that the AGC EDFA has a gain flatness of better than 0.46 dB/40 nm, i.e., below 1.5%, and a higher gain of approximately 36.5 dB compared to that of approximately 35.3 dB for the conventional GC EDFA at -30 dBm input signal power. The best gain flatness of +/-0.25 dB can be achieved over the dynamic range greater than 20 dB. The dynamic range of noise figure is between 6.7 and 7.1. The 3 dB down bandwidth is more than 40 nm. Overall dynamics measurements for the AGC EDFA feedback stabilization have been carried out. The recorded corresponding rise time of 1.565 ms indicates that the system does not exhibit any overshoot of gain or ASE variation due to the signal at the beginning of the pulse.

  16. Automatic Camera Control

    DEFF Research Database (Denmark)

    Burelli, Paolo; Preuss, Mike

    2014-01-01

    Automatically generating computer animations is a challenging and complex problem with applications in games and film production. In this paper, we investigate howto translate a shot list for a virtual scene into a series of virtual camera configurations — i.e automatically controlling the virtual...... camera. We approach this problem by modelling it as a dynamic multi-objective optimisation problem and show how this metaphor allows a much richer expressiveness than a classical single objective approach. Finally, we showcase the application of a multi-objective evolutionary algorithm to generate a shot...

  17. Automaticity or active control

    DEFF Research Database (Denmark)

    Tudoran, Ana Alina; Olsen, Svein Ottar

    aspects of the construct, such as routine, inertia, automaticity, or very little conscious deliberation. The data consist of 2962 consumers participating in a large European survey. The results show that habit strength significantly moderates the association between satisfaction and action loyalty, and......This study addresses the quasi-moderating role of habit strength in explaining action loyalty. A model of loyalty behaviour is proposed that extends the traditional satisfaction–intention–action loyalty network. Habit strength is conceptualised as a cognitive construct to refer to the psychological......, respectively, between intended loyalty and action loyalty. At high levels of habit strength, consumers are more likely to free up cognitive resources and incline the balance from controlled to routine and automatic-like responses....

  18. Comparison of automatic control systems

    Science.gov (United States)

    Oppelt, W

    1941-01-01

    This report deals with a reciprocal comparison of an automatic pressure control, an automatic rpm control, an automatic temperature control, and an automatic directional control. It shows the difference between the "faultproof" regulator and the actual regulator which is subject to faults, and develops this difference as far as possible in a parallel manner with regard to the control systems under consideration. Such as analysis affords, particularly in its extension to the faults of the actual regulator, a deep insight into the mechanism of the regulator process.

  19. 一种低电压、低噪声、低失真度的语音信号自动增益控制电路%A Low Noise Low Distortion Automatic Gain Control Circuit

    Institute of Scientific and Technical Information of China (English)

    王明轩; 李冬梅

    2016-01-01

    This paper presents a kind of Automatic Gain Control (AGC)circuits which can be used in speech signal acquisition system,it has high gain range,low noise and high linearity.The proposed AGC is based on feedback topologies and the gain is digital controlled.The design indexes are 1 V supply voltage,0~40 dB gain range,2 dB gain step,8 kHz bandwidth.Aπ-type resistors network is used in the Programmable Gain Amplifier (PGA)as the passive feedback device to realize gain linearity in decibels and increase the gain accuracy.The hysteresis comparator eliminate the chattering effects when the output signal of Peak Detector changes rapidly around the threshold.The design is implemented in 0.18μm CMOS and occupies an active area of 0.41 mm2 .The power consumption of AGC is about 0.17 mW at 1 V supply voltage.The gain of AGC loop ranges from 0 dB to 40.2 dB in 2 dB step with gain error not more than 0.2 dB.The total harmonic distortion (THD)is below-70 dB over the audio frequencies at 1 kHz,0.4-Vpp differential output.The integrated noise in the audio range (20 Hz~20 kHz)is less than 5μVRMS when the gain of PGA is set at 0 dB.%提出了一种工作在低电压下的宽动态范围、低噪声、低失真度的可用于语音信号采集系统的自动增益控制电路(AGC).该AGC环路采用反馈式结构,数字式增益控制.设计指标为1 V工作电压,0~40 dB增益动态范围,2 dB增益步长,8 kHz带宽.采用π型电阻网络作为环路中可变增益放大器的无源反馈网络,提高增益的准确性并实现增益在对数单位下的线性.采用滞回比较器来减弱当峰值检测器输出信号在阈值电压附近小幅度快速变化而引起的抖动.基于UMC180 nm CMOS工艺完成电路及版图设计,芯片面积约为0.45 mm2.提取版图寄生参数后的电路仿真结果显示,AGC环路的功耗在1 V工作电压下约为0.17 mW;AGC的增益动态范围为0~40.2 dB,增益步长为2 d

  20. Automatic reference level control for an antenna pattern recording system

    Science.gov (United States)

    Lipin, R., Jr.

    1971-01-01

    Automatic gain control system keeps recorder reference levels within 0.2 decibels during operation. System reduces recorder drift during antenna radiation distribution determinations over an eight hour period.

  1. Automatic Control System for Neutron Laboratory Safety

    Institute of Scientific and Technical Information of China (English)

    ZHAO; Xiao; ZHANG; Guo-guang; FENG; Shu-qiang; SU; Dan; YANG; Guo-zhao; ZHANG; Shuai

    2015-01-01

    In order to cooperate with the experiment of neutron generator,and realize the automatic control in the experiment,a set of automatic control system for the safety of the neutron laboratory is designed.The system block diagram is shown as Fig.1.Automatic control device is for processing switch signal,so PLC is selected as the core component

  2. Determination of optimal gains for constrained controllers

    Energy Technology Data Exchange (ETDEWEB)

    Kwan, C.M.; Mestha, L.K.

    1993-08-01

    In this report, we consider the determination of optimal gains, with respect to a certain performance index, for state feedback controllers where some elements in the gain matrix are constrained to be zero. Two iterative schemes for systematically finding the constrained gain matrix are presented. An example is included to demonstrate the procedures.

  3. Gaining and sustaining schistosomiasis control

    DEFF Research Database (Denmark)

    Ezeamama, Amara E.; He, Chun-La; Shen, Ye;

    2016-01-01

    BACKGROUND: The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) was established in 2008 to answer strategic questions about schistosomiasis control. For programme managers, a high-priority question is: what are the most cost-effective strategies for delivering preventiv...

  4. Automatically output-power-controlled WDM EDFA

    Science.gov (United States)

    Choi, Bo-Hun; Lee, Sang Soo; Kim, Chang-Bong; Ko, Jesoo

    2006-09-01

    Our amplifier using an all optical method and a fixed GFF achieved automatic gain flatness through all C-band without any NF degradation, and simultaneously a constant 25 dB gain, while input signals were varied between one channel and forty WDM channels.

  5. Automatic Control of Water Pumping Stations

    Institute of Scientific and Technical Information of China (English)

    Muhannad Alrheeh; JIANG Zhengfeng

    2006-01-01

    Automatic Control of pumps is an interesting proposal to operate water pumping stations among many kinds of water pumping stations according to their functions.In this paper, our pumping station is being used for water supply system. This paper is to introduce the idea of pump controller and the important factors that must be considering when we want to design automatic control system of water pumping stations. Then the automatic control circuit with the function of all components will be introduced.

  6. Gaining and sustaining schistosomiasis control

    DEFF Research Database (Denmark)

    Ezeamama, Amara E.; He, Chun-La; Shen, Ye

    2016-01-01

    BACKGROUND: The Schistosomiasis Consortium for Operational Research and Evaluation (SCORE) was established in 2008 to answer strategic questions about schistosomiasis control. For programme managers, a high-priority question is: what are the most cost-effective strategies for delivering preventive...... chemotherapy (PCT) with praziquantel (PZQ)? This paper describes the process SCORE used to transform this question into a harmonized research protocol, the study design for answering this question, the village eligibility assessments and data resulting from the first year of the study. METHODS: Beginning......-aged children. Seven studies are currently being implemented in five African countries. During the first year, villages were screened for eligibility, and data were collected on prevalence and intensity of infection prior to randomisation and the implementation of different schemes of PZQ intervention...

  7. Gain control mechanisms in spinal motoneurons

    Directory of Open Access Journals (Sweden)

    Michael David Johnson

    2014-07-01

    Full Text Available Motoneurons provide the only conduit for motor commands to reach muscles. For many years, motoneurons were in fact considered to be little more than passive wires. Systematic studies in the past 25 years however have clearly demonstrated that the intrinsic electrical properties of motoneurons are under strong neuromodulatory control via multiple sources. The discovery of potent neuromodulation from the brainstem and its ability to change the gain of motoneurons shows that the passive view of the motor output stage is no longer tenable. A mechanism for gain control at the motor output stage makes good functional sense considering our capability of generating an enormous range of forces, from very delicate (e.g. putting in a contact lens to highly forceful (emergency reactions. Just as sensory systems need gain control to deal with a wide dynamic range of inputs, so to might motor output need gain control to deal with the wide dynamic range of the normal movement repertoire. Two problems emerge from the potential use of the brainstem monoaminergic projection to motoneurons for gain control. First, the projection is highly diffuse anatomically, so that independent control of the gains of different motor pools is not feasible. In fact, the system is so diffuse that gain for all the motor pools in a limb likely increases in concert. Second, if there is a system that increases gain, probably a system to reduce gain is also needed. In this review, we summarize recent studies that show local inhibitory circuits within the spinal cord, especially reciprocal and recurrent inhibition, have the potential to solve both of these problems as well as constitute another source of gain modulation.

  8. Automatic Tuning of the Superheat Controller in a Refrigeration Plant

    DEFF Research Database (Denmark)

    Rasmussen, Henrik; Thybo, Claus; Larsen, Lars F. S.

    2006-01-01

    This paper proposes an automatic tuning of the superheat control in a refrigeration system using a relay method. By means of a simple evaporator model that captures the important dynamics and non-linearities of the superheat a gain-scheduling that compensates for the variation of the process gain...... can be obtained from tuning in only one operation point. The proposed method is validated by experimental results....

  9. On Design of Automatic Choosing Control by Pole Placement

    OpenAIRE

    高田, 等; 提, 祐樹; 八野, 知博; TAKATA, Hitoshi; Sage, Yuki; HACHINO, Tomohiro

    2009-01-01

    This paper is concerned with design of an augmented automatic choosing control (AACC) for nonlinear systems. The AACC is synthesized by smoothly uniting a set of sectionwise linear controls, in which pole placement approach is used. An observer theory is applied to it in a case that the state vector includes some unmeasurable variables directly. Control and observer's gains are obtained by the pole placement method.

  10. 12th Portuguese Conference on Automatic Control

    CERN Document Server

    Soares, Filomena; Moreira, António

    2017-01-01

    The biennial CONTROLO conferences are the main events promoted by The CONTROLO 2016 – 12th Portuguese Conference on Automatic Control, Guimarães, Portugal, September 14th to 16th, was organized by Algoritmi, School of Engineering, University of Minho, in partnership with INESC TEC, and promoted by the Portuguese Association for Automatic Control – APCA, national member organization of the International Federation of Automatic Control – IFAC. The seventy-five papers published in this volume cover a wide range of topics. Thirty-one of them, of a more theoretical nature, are distributed among the first five parts: Control Theory; Optimal and Predictive Control; Fuzzy, Neural and Genetic Control; Modeling and Identification; Sensing and Estimation. The papers go from cutting-edge theoretical research to innovative control applications and show expressively how Automatic Control can be used to increase the well being of people. .

  11. Cognitive adaptation of sonar gain control in the bottlenose dolphin.

    Science.gov (United States)

    Kloepper, Laura N; Smith, Adam B; Nachtigall, Paul E; Buck, John R; Simmons, James A; Pacini, Aude F

    2014-01-01

    Echolocating animals adjust the transmit intensity and receive sensitivity of their sonar in order to regulate the sensation level of their echoes; this process is often termed automatic gain control. Gain control is considered not to be under the animal's cognitive control, but previous investigations studied animals ensonifying targets or hydrophone arrays at predictable distances. To test whether animals maintain gain control at a fixed level in uncertain conditions, we measured changes in signal intensity for a bottlenose dolphin (Tursiops truncatus) detecting a target at three target distances (2.5, 4 and 7 m) in two types of sessions: predictable and unpredictable. Predictable sessions presented the target at a constant distance; unpredictable sessions moved the target randomly between the three target positions. In the predictable sessions the dolphin demonstrated intensity distance compensation, increasing the emitted click intensity as the target distance increased. Additionally, as trials within sessions progressed, the animal adjusted its click intensity even from the first click in a click train, which is consistent with the animal expecting a target at a certain range. In the unpredictable sessions there was no significant difference of intensity with target distance until after the 7th click in a click train. Together, these results demonstrate that the bottlenose dolphin uses learning and expectation for sonar gain control.

  12. Weight Gain Through Self-Control Procedures

    Science.gov (United States)

    Gulanick, Nancy; And Others

    1975-01-01

    Underweight subjects were assigned to either a self-reinforcement condition, a self-punishment condition, or to a discussion/reflection control condition. The subjects received one treatment session per week over a five-week period. After treatment, the self-reinforcement groups gained significantly more pounds (kilograms) than either of the other…

  13. Automatic Control of Freeboard and Turbine Operation

    DEFF Research Database (Denmark)

    Kofoed, Jens Peter; Frigaard, Peter Bak; Friis-Madsen, Erik;

    The report deals with the modules for automatic control of freeboard and turbine operation on board the Wave dragon, Nissum Bredning (WD-NB) prototype, and covers what has been going on up to ultimo 2003.......The report deals with the modules for automatic control of freeboard and turbine operation on board the Wave dragon, Nissum Bredning (WD-NB) prototype, and covers what has been going on up to ultimo 2003....

  14. Method of automatic tuning pf preset coefficient of electron gain of photoelectron multiplier

    CERN Document Server

    Smirnov, O Yu

    2002-01-01

    Paper describes technique to time the preset coefficient of electron gain of photoelectron multiplier (PEM) ensuring high accuracy at minimal involvement of an operator. Subsequent to rough setting of voltage in PEM the automatic system tunes high voltage so that coefficient of electron gain of PEM corresponds to the preset one within the limits of the required accuracy (up to 2%). The technique was efficiently used to tune two thousands of PEMs for the Borexino solar neutrino detector in the Gran Sasso National Laboratory, Italy

  15. Contrast Gain Control Model Fits Masking Data

    Science.gov (United States)

    Watson, Andrew B.; Solomon, Joshua A.; Null, Cynthia H. (Technical Monitor)

    1994-01-01

    We studied the fit of a contrast gain control model to data of Foley (JOSA 1994), consisting of thresholds for a Gabor patch masked by gratings of various orientations, or by compounds of two orientations. Our general model includes models of Foley and Teo & Heeger (IEEE 1994). Our specific model used a bank of Gabor filters with octave bandwidths at 8 orientations. Excitatory and inhibitory nonlinearities were power functions with exponents of 2.4 and 2. Inhibitory pooling was broad in orientation, but narrow in spatial frequency and space. Minkowski pooling used an exponent of 4. All of the data for observer KMF were well fit by the model. We have developed a contrast gain control model that fits masking data. Unlike Foley's, our model accepts images as inputs. Unlike Teo & Heeger's, our model did not require multiple channels for different dynamic ranges.

  16. Automatic speed control of highway traffic

    Science.gov (United States)

    Klingman, E. E.

    1973-01-01

    Vehicle control system monitors all vehicles in its range, and automatically slows down speeding vehicles by activating governor in vehicle. System determines only maximum speed; speeds below maximum are controlled by vehicle operator. Loss of transmitted signal or activation of emergency over-ride will open fuel line and return control to operator.

  17. Gain control in the sonar of odontocetes.

    Science.gov (United States)

    Ya Supin, Alexander; Nachtigall, Paul E

    2013-06-01

    The sonar of odontocetes processes echo-signals within a wide range of echo levels. The level of echoes varies widely by tens of decibels depending on the level of the emitted sonar pulse, the target strength, the distance to the target, and the sound absorption by the water media. The auditory system of odontocetes must be capable of effective perception, analysis, and discrimination of echo-signals within all this variability. The sonar of odontocetes has several mechanisms to compensate for the echo-level variation (gain control). To date, several mechanisms of the biosonar gain control have been revealed in odontocetes: (1) adjustment of emitted sonar pulse levels (the longer the distance to the target, the higher the level of the emitted pulse), (2) short-term variation of hearing sensitivity based on forward masking of the echo by the preceding self-heard emitted pulse and subsequent release from the masking, and (3) active long-term control of hearing sensitivity. Recent investigations with the use of the auditory evoked-potential technique have demonstrated that these mechanisms effectively minimize the variation of the response to the echo when either the emitted sonar pulse level, or the target distance, or both vary within a wide range. A short review of these data is presented herein.

  18. Automatic weld torch guidance control system

    Science.gov (United States)

    Smaith, H. E.; Wall, W. A.; Burns, M. R., Jr.

    1982-01-01

    A highly reliable, fully digital, closed circuit television optical, type automatic weld seam tracking control system was developed. This automatic tracking equipment is used to reduce weld tooling costs and increase overall automatic welding reliability. The system utilizes a charge injection device digital camera which as 60,512 inidividual pixels as the light sensing elements. Through conventional scanning means, each pixel in the focal plane is sequentially scanned, the light level signal digitized, and an 8-bit word transmitted to scratch pad memory. From memory, the microprocessor performs an analysis of the digital signal and computes the tracking error. Lastly, the corrective signal is transmitted to a cross seam actuator digital drive motor controller to complete the closed loop, feedback, tracking system. This weld seam tracking control system is capable of a tracking accuracy of + or - 0.2 mm, or better. As configured, the system is applicable to square butt, V-groove, and lap joint weldments.

  19. Towards Automatic Decentralized Control Structure Selection

    DEFF Research Database (Denmark)

    Jørgensen, John Bagterp; Jørgensen, Sten Bay

    2000-01-01

    A subtask in integration of design and control of chemical processes is the selection of a control structure. Automating the selection of the control structure enables sequential integration of process and control design. As soon as the process is specified or computed, a structure...... for decentralized control is determined automatically, and the resulting decentralized control structure is automatically tuned using standard techniques. Dynamic simulation of the resulting process system gives immediate feedback to the process design engineer regarding practical operability of the process....... The control structure selection problem is formulated as a special MILP employing cost coefficients which are computed using Parseval's theorem combined with RGA and IMC concepts. This approach enables selection and tuning of large-scale plant-wide decentralized controllers through efficient combination...

  20. Automatic Control of Personal Rapid Transit Vehicles

    Science.gov (United States)

    Smith, P. D.

    1972-01-01

    The requirements for automatic longitudinal control of a string of closely packed personal vehicles are outlined. Optimal control theory is used to design feedback controllers for strings of vehicles. An important modification of the usual optimal control scheme is the inclusion of jerk in the cost functional. While the inclusion of the jerk term was considered, the effect of its inclusion was not sufficiently studied. Adding the jerk term will increase passenger comfort.

  1. Design and research on automatic gain control circuit in wireless positioning system%无线定位系统中自动增益控制电路的设计与研究

    Institute of Scientific and Technical Information of China (English)

    周永强

    2016-01-01

    针对卫星无线定位系统,其民用需求加大,促使商业上对更为廉价、更低功耗的射频收发前端技术进行研究和探索。设计实现了一款用于无线定位系统的数字可编程增益控制系统,可用于IMT⁃Advanced新一代4G无线通信网络中。对模拟控制和数字可编程两种模式进行了系统上的分析,针对系统建立数学模型,进行了可行性研究。在设计该芯片的同时,对具体模块的不同实现形式进行了阐述,并提出了可优化的结构。%Since the civilian requirement of satellite wireless positioning system is increased,the cheaper and lower⁃power consumption RF receiving front⁃end technology is studied and explored for business. A digital programmable gain control system used for wireless positioning system was designed and implemented,which can be applied to the emerging IMT⁃Advanced new generation 4G wireless communication network. The analog control mode and digital programmable mode are analyzed systemati⁃cally. The mathematical model of the system was established to study the feasibility. The different realization forms of the speci⁃fic module are described while designing the chip,and the optimizable structures are proposed.

  2. Towards Automatic Decentralized Control Structure Selection

    DEFF Research Database (Denmark)

    for decentralized control is determined automatically, and the resulting decentralized control structure is automatically tuned using standard techniques. Dynamic simulation of the resulting process system gives immediate feedback to the process design engineer regarding practical operability of the process......A subtask in integration of design and control of chemical processes is the selection of a control structure. Automating the selection of the control structure enables sequential integration of process and controld esign. As soon as the process is specified or computed, a structure....... The control structure selection problem is formulated as a special MILP employing cost coefficients which are computed using Parseval's theorem combined with RGA and IMC concepts. This approach enables selection and tuning of large-scale plant-wide decentralized controllers through efficient combination...

  3. Automatic contour welder incorporates speed control system

    Science.gov (United States)

    Wall, W. A., Jr.

    1968-01-01

    Speed control system maintains the welding torch of an automatic welder at a substantially constant speed. The system is particularly useful when welding contoured or unusually shaped surfaces, which cause the distance from the work surface to the weld carriage to vary in a random manner.

  4. Automatic solar lamp intensity control system

    Science.gov (United States)

    Leverone, H.; Mandell, N.

    1968-01-01

    System that substitutes solar cells directly in the path of the radiation incident on the test volume and uses a dc bridge-null system was developed. The solar cell is affixed to a heat sink mounted on each of three arms for each solar lamp. Control of the radiation from the solar lamps is automatic.

  5. Automatic-Control System for Safer Brazing

    Science.gov (United States)

    Stein, J. A.; Vanasse, M. A.

    1986-01-01

    Automatic-control system for radio-frequency (RF) induction brazing of metal tubing reduces probability of operator errors, increases safety, and ensures high-quality brazed joints. Unit combines functions of gas control and electric-power control. Minimizes unnecessary flow of argon gas into work area and prevents electrical shocks from RF terminals. Controller will not allow power to flow from RF generator to brazing head unless work has been firmly attached to head and has actuated micro-switch. Potential shock hazard eliminated. Flow of argon for purging and cooling must be turned on and adjusted before brazing power applied. Provision ensures power not applied prematurely, causing damaged work or poor-quality joints. Controller automatically turns off argon flow at conclusion of brazing so potentially suffocating gas does not accumulate in confined areas.

  6. Automatic oscillator frequency control system

    Science.gov (United States)

    Smith, S. F. (Inventor)

    1985-01-01

    A frequency control system makes an initial correction of the frequency of its own timing circuit after comparison against a frequency of known accuracy and then sequentially checks and corrects the frequencies of several voltage controlled local oscillator circuits. The timing circuit initiates the machine cycles of a central processing unit which applies a frequency index to an input register in a modulo-sum frequency divider stage and enables a multiplexer to clock an accumulator register in the divider stage with a cyclical signal derived from the oscillator circuit being checked. Upon expiration of the interval, the processing unit compares the remainder held as the contents of the accumulator against a stored zero error constant and applies an appropriate correction word to a correction stage to shift the frequency of the oscillator being checked. A signal from the accumulator register may be used to drive a phase plane ROM and, with periodic shifts in the applied frequency index, to provide frequency shift keying of the resultant output signal. Interposition of a phase adder between the accumulator register and phase plane ROM permits phase shift keying of the output signal by periodic variation in the value of a phase index applied to one input of the phase adder.

  7. 11th Portuguese Conference on Automatic Control

    CERN Document Server

    Matos, Aníbal; Veiga, Germano

    2015-01-01

    During the last 20 years the Portuguese association of automatic control, Associação Portuguesa de Controlo Automático, with the sponsorship of IFAC have established the CONTROLO conference as a reference international forum where an effective exchange of knowledge and experience amongst researchers active in various theoretical and applied areas of systems and control can take place, always including considerable space for promoting new technical applications and developments, real-world challenges and success stories. In this 11th edition the CONTROLO conference evolved by introducing two strategic partnerships with Spanish and Brazilian associations in automatic control, Comité Español de Automática and Sociedade Brasileira de Automatica, respectively.

  8. Automatic control algorithm effects on energy production

    Science.gov (United States)

    Mcnerney, G. M.

    1981-01-01

    A computer model was developed using actual wind time series and turbine performance data to simulate the power produced by the Sandia 17-m VAWT operating in automatic control. The model was used to investigate the influence of starting algorithms on annual energy production. The results indicate that, depending on turbine and local wind characteristics, a bad choice of a control algorithm can significantly reduce overall energy production. The model can be used to select control algorithms and threshold parameters that maximize long term energy production. The results from local site and turbine characteristics were generalized to obtain general guidelines for control algorithm design.

  9. Automatic Configuration of Programmable Logic Controller Emulators

    Science.gov (United States)

    2015-03-01

    algorithms and constructs used in reversing protocols. Reverse engineering protocols is similar to trying to learn a new language. First, a vocabulary ...AUTOMATIC CONFIGURATION OF PROGRAMMABLE LOGIC CONTROLLER EMULATORS THESIS Phillip C. Warner, Captain, USAF AFIT-ENG-MS-15-M-024 DEPARTMENT OF THE AIR... THESIS Presented to the Faculty Department of Electrical and Computer Engineering Graduate School of Engineering and Management Air Force Institute of

  10. Stabilizing Gain Selection of Networked Variable Gain Controller to Maximize Robustness Using Particle Swarm Optimization

    CERN Document Server

    Pan, Indranil; Ghosh, Soumyajit; Gupta, Amitava; 10.1109/PACC.2011.5978958

    2012-01-01

    Networked Control Systems (NCSs) are often associated with problems like random data losses which might lead to system instability. This paper proposes a method based on the use of variable controller gains to achieve maximum parametric robustness of the plant controlled over a network. Stability using variable controller gains under data loss conditions is analyzed using a suitable Linear Matrix Inequality (LMI) formulation. Also, a Particle Swarm Optimization (PSO) based technique is used to maximize parametric robustness of the plant.

  11. Automatic Synthesis of Robust and Optimal Controllers

    DEFF Research Database (Denmark)

    Cassez, Franck; Jessen, Jan Jacob; Larsen, Kim Guldstrand;

    2009-01-01

    In this paper, we show how to apply recent tools for the automatic synthesis of robust and near-optimal controllers for a real industrial case study. We show how to use three different classes of models and their supporting existing tools, Uppaal-TiGA for synthesis, phaver for verification......, and Simulink for simulation, in a complementary way. We believe that this case study shows that our tools have reached a level of maturity that allows us to tackle interesting and relevant industrial control problems....

  12. Automatic Flatness Control of Cold Rolling Mill

    Science.gov (United States)

    Anbe, Yoshiharu; Sekiguchi, Kunio

    One of the subjects of cold rolling is a flatness of the rolled strip. Conventionally, measured strip flatness was approximated by polynomial (2th, 4th, 6th) equation across the entire strip width. This made it difficult to deal with desired loose edge or any desired flatness across the entire strip width. Also conventional flatness control was done for the entire strip width, so if there is a different flatness error among drive side and work side, conventional flatness control can not control properly. We propose independent strip flatness control among drive side and work side, and also automatic flatness control (AFC) system with arbitrary desired strip flatness. Also some applied results to cold mill are shown.

  13. Pilot control through the TAFCOS automatic flight control system

    Science.gov (United States)

    Wehrend, W. R., Jr.

    1979-01-01

    The set of flight control logic used in a recently completed flight test program to evaluate the total automatic flight control system (TAFCOS) with the controller operating in a fully automatic mode, was used to perform an unmanned simulation on an IBM 360 computer in which the TAFCOS concept was extended to provide a multilevel pilot interface. A pilot TAFCOS interface for direct pilot control by use of a velocity-control-wheel-steering mode was defined as well as a means for calling up conventional autopilot modes. It is concluded that the TAFCOS structure is easily adaptable to the addition of a pilot control through a stick-wheel-throttle control similar to conventional airplane controls. Conventional autopilot modes, such as airspeed-hold, altitude-hold, heading-hold, and flight path angle-hold, can also be included.

  14. Bumpless Transfer between Observer-based Gain Scheduled Controllers

    DEFF Research Database (Denmark)

    Bendtsen, Jan Dimon; Stoustrup, Jakob; Trangbæk, Klaus

    2005-01-01

    This paper deals with bumpless transfer between a number of observer-based controllers in a gain scheduling architecture. Linear observer-based controllers are designed for a number of linear approximations of a nonlinear system in a set of operating points, and gain scheduling control can...

  15. Aircraft nonlinear optimal control using fuzzy gain scheduling

    Science.gov (United States)

    Nusyirwan, I. F.; Kung, Z. Y.

    2016-10-01

    Fuzzy gain scheduling is a common solution for nonlinear flight control. The highly nonlinear region of flight dynamics is determined throughout the examination of eigenvalues and the irregular pattern of root locus plots that show the nonlinear characteristic. By using the optimal control for command tracking, the pitch rate stability augmented system is constructed and the longitudinal flight control system is established. The outputs of optimal control for 21 linear systems are fed into the fuzzy gain scheduler. This research explores the capability in using both optimal control and fuzzy gain scheduling to improve the efficiency in finding the optimal control gains and to achieve Level 1 flying qualities. The numerical simulation work is carried out to determine the effectiveness and performance of the entire flight control system. The simulation results show that the fuzzy gain scheduling technique is able to perform in real time to find near optimal control law in various flying conditions.

  16. Scheduling algorithms for automatic control systems for technological processes

    Science.gov (United States)

    Chernigovskiy, A. S.; Tsarev, R. Yu; Kapulin, D. V.

    2017-01-01

    Wide use of automatic process control systems and the usage of high-performance systems containing a number of computers (processors) give opportunities for creation of high-quality and fast production that increases competitiveness of an enterprise. Exact and fast calculations, control computation, and processing of the big data arrays – all of this requires the high level of productivity and, at the same time, minimum time of data handling and result receiving. In order to reach the best time, it is necessary not only to use computing resources optimally, but also to design and develop the software so that time gain will be maximal. For this purpose task (jobs or operations), scheduling techniques for the multi-machine/multiprocessor systems are applied. Some of basic task scheduling methods for the multi-machine process control systems are considered in this paper, their advantages and disadvantages come to light, and also some usage considerations, in case of the software for automatic process control systems developing, are made.

  17. Automatic Control of ITER-like Structures

    Energy Technology Data Exchange (ETDEWEB)

    Bosia, G.; Bremond, S

    2005-07-01

    In ITER Ion Cyclotron System requires a power transfer efficiency in excess of 90% from power source to plasma in quasi continuous operation. This implies the availability of a control system capable of optimizing the array radiation spectrum, automatically acquiring impedance match between the power source and the plasma loaded array at the beginning of the power pulse and maintaining it against load variations due to plasma position and plasma edge parameters fluctuations, rapidly detecting voltage breakdowns in the array and/or in the transmission system and reliably discriminating them from fast load variations. In this paper a proposal for a practical ITER control system, including power, phase, frequency and impedance matching is described. (authors)

  18. A novel control method for on-off gain and gain tilt of fiber Raman amplifiers

    Institute of Scientific and Technical Information of China (English)

    Xue Feng(冯雪); Wei Zhang(张巍); Xiaoming Liu(刘小明); Jiangde Peng(彭江得)

    2004-01-01

    Considering spectrum tilt due to signal-to-signal Raman scattering (SSRS) in backward distributed fiber Raman amplifiers (B-DFRA), an inverse tilted on-off gain profile is adopted to achieve flat net gain. A simple approximate linear relationship of pump power at each wavelength versus on-off gain level and tilt was derived numerically and experimentally so that a novel control method was established. Since there are only 3 pre-determinable constants required for individual pump wave, it is easy to be realized. As an example, maximum errors less than 0.2 and 0.4 dB respectively for average gain and gain tilt were achieved over C+L band in 100-km back-pumped standard single-mode fiber (SMF) experimentally.

  19. 2nd International Conference on Mechatronics and Automatic Control

    CERN Document Server

    2015-01-01

    This book examines mechatronics and automatic control systems. The book covers important emerging topics in signal processing, control theory, sensors, mechanic manufacturing systems and automation. The book presents papers from the second International Conference on Mechatronics and Automatic Control Systems held in Beijing, China on September 20-21, 2014. Examines how to improve productivity through the latest advanced technologies Covering new systems and techniques in the broad field of mechatronics and automatic control systems.

  20. Improved automatic tuning of PID controller for stable processes.

    Science.gov (United States)

    Kumar Padhy, Prabin; Majhi, Somanath

    2009-10-01

    This paper presents an improved automatic tuning method for stable processes using a modified relay in the presence of static load disturbances and measurement noise. The modified relay consists of a standard relay in series with a PI controller of unity proportional gain. The integral time constant of the PI controller of the modified relay is chosen so as to ensure a minimum loop phase margin of 30( composite function). A limit cycle is then obtained using the modified relay. Hereafter, the PID controller is designed using the limit cycle output data. The derivative time constant is obtained by maintaining the above mentioned loop phase margin. Minimizing the distance of Nyquist curve of the loop transfer function from the imaginary axis of the complex plane gives the proportional gain. The integral time constant of the PID controller is set equal to the integral time constant of the PI controller of the modified relay. The effectiveness of the proposed technique is verified by simulation results.

  1. Adaptive Human Control Gains During Precision Grip

    Directory of Open Access Journals (Sweden)

    Erik D. Engeberg

    2013-03-01

    Full Text Available Eight human test subjects attempted to track a desired position trajectory with an instrumented manipulandum (MN. The test subjects used the MN with three different levels of stiffness. A transfer function was developed to represent the human application of a precision grip from the data when the test subjects initially displaced the MN so as to learn the position mapping from the MN onto the display. Another transfer function was formed from the data of the remainder of the experiments, after significant displacement of the MN occurred. Both of these transfer functions accurately modelled the system dynamics for a portion of the experiments, but neither was accurate for the duration of the experiments because the human grip dynamics changed while learning the position mapping. Thus, an adaptive system model was developed to describe the learning process of the human test subjects as they displaced the MN in order to gain knowledge of the position mapping. The adaptive system model was subsequently validated following comparison with the human test subject data. An examination of the average absolute error between the position predicted by the adaptive model and the actual experimental data yielded an overall average error of 0.34mm for all three levels of stiffness.

  2. L2-gain and passivity techniques in nonlinear control

    CERN Document Server

    van der Schaft, Arjan

    2017-01-01

    This standard text gives a unified treatment of passivity and L2-gain theory for nonlinear state space systems, preceded by a compact treatment of classical passivity and small-gain theorems for nonlinear input-output maps. The synthesis between passivity and L2-gain theory is provided by the theory of dissipative systems. Specifically, the small-gain and passivity theorems and their implications for nonlinear stability and stabilization are discussed from this standpoint. The connection between L2-gain and passivity via scattering is detailed. Feedback equivalence to a passive system and resulting stabilization strategies are discussed. The passivity concepts are enriched by a generalised Hamiltonian formalism, emphasising the close relations with physical modeling and control by interconnection, and leading to novel control methodologies going beyond passivity. The potential of L2-gain techniques in nonlinear control, including a theory of all-pass factorizations of nonlinear systems, and of parametrization...

  3. Automatic charge control system for satellites

    Science.gov (United States)

    Shuman, B. M.; Cohen, H. A.

    1985-01-01

    The SCATHA and the ATS-5 and 6 spacecraft provided insights to the problem of spacecraft charging at geosychronous altitudes. Reduction of the levels of both absolute and differential charging was indicated, by the emission of low energy neutral plasma. It is appropriate to complete the transition from experimental results to the development of a system that will sense the state-of-charge of a spacecraft, and, when a predetermined threshold is reached, will respond automatically to reduce it. A development program was initiated utilizing sensors comparable to the proton electrostatic analyzer, the surface potential monitor, and the transient pulse monitor that flew in SCATHA, and combine these outputs through a microprocessor controller to operate a rapid-start, low energy plasma source.

  4. Automatic Level Control for Video Cameras towards HDR Techniques

    Directory of Open Access Journals (Sweden)

    de With PeterHN

    2010-01-01

    Full Text Available We give a comprehensive overview of the complete exposure processing chain for video cameras. For each step of the automatic exposure algorithm we discuss some classical solutions and propose their improvements or give new alternatives. We start by explaining exposure metering methods, describing types of signals that are used as the scene content descriptors as well as means to utilize these descriptors. We also discuss different exposure control types used for the control of lens, integration time of the sensor, and gain control, such as a PID control, precalculated control based on the camera response function, and propose a new recursive control type that matches the underlying image formation model. Then, a description of commonly used serial control strategy for lens, sensor exposure time, and gain is presented, followed by a proposal of a new parallel control solution that integrates well with tone mapping and enhancement part of the image pipeline. Parallel control strategy enables faster and smoother control and facilitates optimally filling the dynamic range of the sensor to improve the SNR and an image contrast, while avoiding signal clipping. This is archived by the proposed special control modes used for better display and correct exposure of both low-dynamic range and high-dynamic range images. To overcome the inherited problems of limited dynamic range of capturing devices we discuss a paradigm of multiple exposure techniques. Using these techniques we can enable a correct rendering of difficult class of high-dynamic range input scenes. However, multiple exposure techniques bring several challenges, especially in the presence of motion and artificial light sources such as fluorescent lights. In particular, false colors and light-flickering problems are described. After briefly discussing some known possible solutions for the motion problem, we focus on solving the fluorescence-light problem. Thereby, we propose an algorithm for

  5. Help Your Child Gain Control Over Asthma

    Science.gov (United States)

    ... a pet inside, keep it out of your child’s bedroom. • Keep pets off of your furniture. • Vacuum carpets and furniture when your child is not around. Vacuum every week to help control pet hair and dust. 23 Cockroaches (“roaches” or other “ ...

  6. An electronically controlled automatic security access gate

    Directory of Open Access Journals (Sweden)

    Jonathan A. ENOKELA

    2014-11-01

    Full Text Available The security challenges being encountered in many places require electronic means of controlling access to communities, recreational centres, offices, and homes. The electronically controlled automated security access gate being proposed in this work helps to prevent an unwanted access to controlled environments. This is achieved mainly through the use of a Radio Frequency (RF transmitter-receiver pair. In the design a microcontroller is programmed to decode a given sequence of keys that is entered on a keypad and commands a transmitter module to send out this code as signal at a given radio frequency. Upon reception of this RF signal by the receiver module, another microcontroller activates a driver circuitry to operate the gate automatically. The codes for the microcontrollers were written in C language and were debugged and compiled using the KEIL Micro vision 4 integrated development environment. The resultant Hex files were programmed into the memories of the microcontrollers with the aid of a universal programmer. Software simulation was carried out using the Proteus Virtual System Modeling (VSM version 7.7. A scaled-down prototype of the system was built and tested. The electronically controlled automated security access gate can be useful in providing security for homes, organizations, and automobile terminals. The four-character password required to operate the gate gives the system an increased level of security. Due to its standalone nature of operation the system is cheaper to maintain in comparison with a manually operated type.

  7. 49 CFR 236.825 - System, automatic train control.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false System, automatic train control. 236.825 Section..., INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.825 System, automatic train control. A system so arranged that its operation will...

  8. 2013 International Conference on Mechatronics and Automatic Control Systems

    CERN Document Server

    2014-01-01

    This book examines mechatronics and automatic control systems. The book covers important emerging topics in signal processing, control theory, sensors, mechanic manufacturing systems and automation. The book presents papers from the 2013 International Conference on Mechatronics and Automatic Control Systems held in Hangzhou, China on August 10-11, 2013. .

  9. Gain scheduled control of linear systems with unsymmetrical saturation actuators

    Science.gov (United States)

    Wu, Wen-Juan; Duan, Guang-Ren

    2016-11-01

    The problem of stabilisation of a class of nonlinear continuous-time systems with asymmetric saturations on the control is studied in this paper. By combining the parametric Lyapunov equation approach and gain scheduling technique, a state feedback gain scheduling controller is proposed to solve the stabilisation problem of systems with unsymmetrical saturated control. The proposed gain scheduled approach is to increase the value of the design parameter so that the convergence rate of the closed-loop system can be increased. Numerical simulations show the effectiveness of the proposed approach.

  10. Gain Scheduling for the Orion Launch Abort Vehicle Controller

    Science.gov (United States)

    McNamara, Sara J.; Restrepo, Carolina I.; Madsen, Jennifer M.; Medina, Edgar A.; Proud, Ryan W.; Whitley, Ryan J.

    2011-01-01

    One of NASAs challenges for the Orion vehicle is the control system design for the Launch Abort Vehicle (LAV), which is required to abort safely at any time during the atmospheric ascent portion of ight. The focus of this paper is the gain design and scheduling process for a controller that covers the wide range of vehicle configurations and flight conditions experienced during the full envelope of potential abort trajectories from the pad to exo-atmospheric flight. Several factors are taken into account in the automation process for tuning the gains including the abort effectors, the environmental changes and the autopilot modes. Gain scheduling is accomplished using a linear quadratic regulator (LQR) approach for the decoupled, simplified linear model throughout the operational envelope in time, altitude and Mach number. The derived gains are then implemented into the full linear model for controller requirement validation. Finally, the gains are tested and evaluated in a non-linear simulation using the vehicles ight software to ensure performance requirements are met. An overview of the LAV controller design and a description of the linear plant models are presented. Examples of the most significant challenges with the automation of the gain tuning process are then discussed. In conclusion, the paper will consider the lessons learned through out the process, especially in regards to automation, and examine the usefulness of the gain scheduling tool and process developed as applicable to non-Orion vehicles.

  11. Gain Scheduling Control based on Closed-Loop System Identification

    DEFF Research Database (Denmark)

    Bendtsen, Jan Dimon; Trangbæk, Klaus

    This paper deals with system identification and gain scheduling control of multi-variable nonlinear systems. We propose a novel scheme where a linear approximation of the system model is obtained in an operating point; then, a Youla-Kucera (YJBK) parameter specifying the difference between...... the first and a second operating point is identified in closed-loop using system identification methods with open-loop properties. Next, a linear controller is designed for this linearised model, and gain scheduling control can subsequently be achieved by interpolating between each controller...

  12. Humanoid Walking Robot: Modeling, Inverse Dynamics, and Gain Scheduling Control

    OpenAIRE

    Elvedin Kljuno; Williams, Robert L.

    2010-01-01

    This article presents reference-model-based control design for a 10 degree-of-freedom bipedal walking robot, using nonlinear gain scheduling. The main goal is to show concentrated mass models can be used for prediction of the required joint torques for a bipedal walking robot. Relatively complicated architecture, high DOF, and balancing requirements make the control task of these robots difficult. Although linear control techniques can be used to control bipedal robots, nonlinear control is n...

  13. A simple readout electronics for automatic power controlled self-mixing laser diode systems.

    Science.gov (United States)

    Cattini, Stefano; Rovati, Luigi

    2008-08-01

    The paper describes a simple electronic circuit to drive a laser diode for self-mixing interferometry. The network integrates a stable commercial automatic power controller and a current mirror based readout of the interferometric signal. The first prototype version of the circuit has been realized and characterized. The system allows easily performing precise interferometric measurements with no thermostatic circuitry to stabilize the laser diode temperature and an automatic control gain network to compensate emitted optical power fluctuations. To achieve this result, in the paper a specific calibration procedure to be performed is described.

  14. Solution to automatic generation control problem using firefly algorithm optimized I(λ)D(µ) controller.

    Science.gov (United States)

    Debbarma, Sanjoy; Saikia, Lalit Chandra; Sinha, Nidul

    2014-03-01

    Present work focused on automatic generation control (AGC) of a three unequal area thermal systems considering reheat turbines and appropriate generation rate constraints (GRC). A fractional order (FO) controller named as I(λ)D(µ) controller based on crone approximation is proposed for the first time as an appropriate technique to solve the multi-area AGC problem in power systems. A recently developed metaheuristic algorithm known as firefly algorithm (FA) is used for the simultaneous optimization of the gains and other parameters such as order of integrator (λ) and differentiator (μ) of I(λ)D(µ) controller and governor speed regulation parameters (R). The dynamic responses corresponding to optimized I(λ)D(µ) controller gains, λ, μ, and R are compared with that of classical integer order (IO) controllers such as I, PI and PID controllers. Simulation results show that the proposed I(λ)D(µ) controller provides more improved dynamic responses and outperforms the IO based classical controllers. Further, sensitivity analysis confirms the robustness of the so optimized I(λ)D(µ) controller to wide changes in system loading conditions and size and position of SLP. Proposed controller is also found to have performed well as compared to IO based controllers when SLP takes place simultaneously in any two areas or all the areas. Robustness of the proposed I(λ)D(µ) controller is also tested against system parameter variations.

  15. New functional units for coke machine automatic control system

    Energy Technology Data Exchange (ETDEWEB)

    Parfenov, G.I.; Bannikov, L.S.; Vakarenko, I.M.; Grishin, S.P.

    1983-01-01

    A new device used in the control systems of coking plants is discussed. The system is capable of operating in fully automatic, semi-automatic, or manual modes. Examples of the usage of the unit include the stopping of coke machines within limits of +/- 200 mm. It is concluded that the use of the units reduce manufacture, adjustment, and service costs.

  16. A method of automatic control procedures cardiopulmonary resuscitation

    Science.gov (United States)

    Bureev, A. Sh.; Zhdanov, D. S.; Kiseleva, E. Yu.; Kutsov, M. S.; Trifonov, A. Yu.

    2015-11-01

    The study is to present the results of works on creation of methods of automatic control procedures of cardiopulmonary resuscitation (CPR). A method of automatic control procedure of CPR by evaluating the acoustic data of the dynamics of blood flow in the bifurcation of carotid arteries and the dynamics of air flow in a trachea according to the current guidelines for CPR is presented. Evaluation of the patient is carried out by analyzing the respiratory noise and blood flow in the interspaces between the chest compressions and artificial pulmonary ventilation. The device operation algorithm of automatic control procedures of CPR and its block diagram has been developed.

  17. A formal structure for advanced automatic flight-control systems

    Science.gov (United States)

    Meyer, G.; Cicolani, L. S.

    1975-01-01

    Techniques were developed for the unified design of multimode, variable authority automatic flight-control systems for powered-lift STOL and VTOL aircraft. A structure for such systems is developed to deal with the strong nonlinearities inherent in this class of aircraft, to admit automatic coupling with advanced air traffic control, and to admit a variety of active control tasks. The aircraft being considered is the augmentor wing jet STOL research aircraft.

  18. Application of gain scheduling to the control of batch bioreactors

    Science.gov (United States)

    Cardello, Ralph; San, Ka-Yiu

    1987-01-01

    The implementation of control algorithms to batch bioreactors is often complicated by the inherent variations in process dynamics during the course of fermentation. Such a wide operating range may render the performance of fixed gain PID controllers unsatisfactory. In this work, a detailed study on the control of batch fermentation is performed. Furthermore, a simple batch controller design is proposed which incorporates the concept of gain-scheduling, a subclass of adaptive control, with oxygen uptake rate as an auxiliary variable. The control of oxygen tension in the biorector is used as a vehicle to convey the proposed idea, analysis and results. Simulation experiments indicate significant improvement in controller performance can be achieved by the proposed approach even in the presence of measurement noise.

  19. Robust parameter design for automatically controlled systems and nanostructure synthesis

    Science.gov (United States)

    Dasgupta, Tirthankar

    2007-12-01

    This research focuses on developing comprehensive frameworks for developing robust parameter design methodology for dynamic systems with automatic control and for synthesis of nanostructures. In many automatically controlled dynamic processes, the optimal feedback control law depends on the parameter design solution and vice versa and therefore an integrated approach is necessary. A parameter design methodology in the presence of feedback control is developed for processes of long duration under the assumption that experimental noise factors are uncorrelated over time. Systems that follow a pure-gain dynamic model are considered and the best proportional-integral and minimum mean squared error control strategies are developed by using robust parameter design. The proposed method is illustrated using a simulated example and a case study in a urea packing plant. This idea is also extended to cases with on-line noise factors. The possibility of integrating feedforward control with a minimum mean squared error feedback control scheme is explored. To meet the needs of large scale synthesis of nanostructures, it is critical to systematically find experimental conditions under which the desired nanostructures are synthesized reproducibly, at large quantity and with controlled morphology. The first part of the research in this area focuses on modeling and optimization of existing experimental data. Through a rigorous statistical analysis of experimental data, models linking the probabilities of obtaining specific morphologies to the process variables are developed. A new iterative algorithm for fitting a Multinomial GLM is proposed and used. The optimum process conditions, which maximize the above probabilities and make the synthesis process less sensitive to variations of process variables around set values, are derived from the fitted models using Monte-Carlo simulations. The second part of the research deals with development of an experimental design methodology, tailor

  20. Control of Spacecraft Formation with Disturbance Rejection and Exponential Gains

    Directory of Open Access Journals (Sweden)

    R. Schlanbusch

    2013-01-01

    Full Text Available We address the problem of state feedback translational motion control of a spacecraft formation through a modified sliding surface controller using variable gains and I^2 action for disturbance rejection. The exponential varying gains ensure faster convergence of the state trajectories during attitude maneuver while keeping the gains small (and the system less stiff for station keeping. Integral action is introduced for rejection of disturbances with a constant nonzero mean such as aerodynamic drag. A direct consequence is a drop in energy consumption when affected by sensor noise and a decrease in size of the error states residual when operating close to the equilibrium point. A large number of simulation results are presented to show the control performance.

  1. Gain-assisted control of the Goos-Haenchen shift

    Energy Technology Data Exchange (ETDEWEB)

    Ziauddin,; Qamar, Sajid [Centre for Quantum Physics, COMSATS Institute of Information Technology, Islamabad (Pakistan); Department of Physics, COMSATS Institute of Information Technology, Islamabad (Pakistan)

    2011-11-15

    A gain-assisted model is considered to study the Goos-Haenchen (GH) shift behavior in the reflected and transmitted light. In this model, a probe light is incident on a cavity containing three-level dilute gaseous atomic medium. The atom-field interaction follows two-photon Raman transitions, and the dielectric susceptibility of the medium exhibits dispersion and gain properties [L. J. Wang, A. Kuzmich, and A. Dogariu, Nature (London) 406, 227 (2000)]. Under appropriate conditions, two gain peaks are observed with anomalous dispersion between the peaks, whereas normal dispersion can be observed at and around the gain maxima. The manipulation of the detuning associated with the probe light field which interacts with the intracavity medium during its propagation through the cavity can lead to a control over negative and positive GH shift in the reflected and transmitted light beam via the anomalous and normal dispersion of the medium.

  2. Choosing Actuators for Automatic Control Systems of Thermal Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Gorbunov, A. I., E-mail: gor@tornado.nsk.ru [JSC “Tornado Modular Systems” (Russian Federation); Serdyukov, O. V. [Siberian Branch of the Russian Academy of Sciences, Institute of Automation and Electrometry (Russian Federation)

    2015-03-15

    Two types of actuators for automatic control systems of thermal power plants are analyzed: (i) pulse-controlled actuator and (ii) analog-controlled actuator with positioning function. The actuators are compared in terms of control circuit, control accuracy, reliability, and cost.

  3. Intelligent control schemes applied to Automatic Generation Control

    Directory of Open Access Journals (Sweden)

    Dingguo Chen

    2016-04-01

    Full Text Available Integrating ever increasing amount of renewable generating resources to interconnected power systems has created new challenges to the safety and reliability of today‟s power grids and posed new questions to be answered in the power system modeling, analysis and control. Automatic Generation Control (AGC must be extended to be able to accommodate the control of renewable generating assets. In addition, AGC is mandated to operate in accordance with the NERC‟s Control Performance Standard (CPS criteria, which represent a greater flexibility in relaxing the control of generating resources and yet assuring the stability and reliability of interconnected power systems when each balancing authority operates in full compliance. Enhancements in several aspects to the traditional AGC must be made in order to meet the aforementioned challenges. It is the intention of this paper to provide a systematic, mathematical formulation for AGC as a first attempt in the context of meeting the NERC CPS requirements and integrating renewable generating assets, which has not been seen reported in the literature to the best knowledge of the authors. Furthermore, this paper proposes neural network based predictive control schemes for AGC. The proposed controller is capable of handling complicated nonlinear dynamics in comparison with the conventional Proportional Integral (PI controller which is typically most effective to handle linear dynamics. The neural controller is designed in such a way that it has the capability of controlling the system generation in the relaxed manner so the ACE is controlled to a desired range instead of driving it to zero which would otherwise increase the control effort and cost; and most importantly the resulting system control performance meets the NERC CPS requirements and/or the NERC Balancing Authority’s ACE Limit (BAAL compliance requirements whichever are applicable.

  4. Observer-based H-infinity output feedback control with feedback gain and observer gain variations for Delta operator system

    Institute of Scientific and Technical Information of China (English)

    Ruiquan LIN; Fuwen YANG; Renchong PENG

    2009-01-01

    Considering that the controller feedback gain and the observer gain are of additive norm-bounded variations, a design method of observer-based H-infinity output feedback controller for uncertain Delta operator systems is proposed in this paper. A sufficient condition of such controllers is presented in linear matrix inequality (LMI) forms. A numerical example is then given to illustrate the effectiveness of this method, that is, the obtained controller guarantees the closed-loop system asymptotically stable and the expected H-infinity performance even if the controller feedback gain and the observer gain are varied.

  5. Adaptive Neuro-Fuzzy Based Gain Controller for Erbium-Doped Fiber Amplifiers

    Directory of Open Access Journals (Sweden)

    YUCEL, M.

    2017-02-01

    Full Text Available Erbium-doped fiber amplifiers (EDFA must have a flat gain profile which is a very important parameter such as wavelength division multiplexing (WDM and dense WDM (DWDM applications for long-haul optical communication systems and networks. For this reason, it is crucial to hold a stable signal power per optical channel. For the purpose of overcoming performance decline of optical networks and long-haul optical systems, the gain of the EDFA must be controlled for it to be fixed at a high speed. In this study, due to the signal power attenuation in long-haul fiber optic communication systems and non-equal signal amplification in each channel, an automatic gain controller (AGC is designed based on the adaptive neuro-fuzzy inference system (ANFIS for EDFAs. The intelligent gain controller is implemented and the performance of this new electronic control method is demonstrated. The proposed ANFIS-based AGC-EDFA uses the experimental dataset to produce the ANFIS-based sets and the rule base. Laser diode currents are predicted within the accuracy rating over 98 percent with the proposed ANFIS-based system. Upon comparing ANFIS-based AGC-EDFA and experimental results, they were found to be very close and compatible.

  6. Tunning PID controller using particle swarm optimization algorithm on automatic voltage regulator system

    Science.gov (United States)

    Aranza, M. F.; Kustija, J.; Trisno, B.; Hakim, D. L.

    2016-04-01

    PID Controller (Proportional Integral Derivative) was invented since 1910, but till today still is used in industries, even though there are many kind of modern controllers like fuzz controller and neural network controller are being developed. Performance of PID controller is depend on on Proportional Gain (Kp), Integral Gain (Ki) and Derivative Gain (Kd). These gains can be got by using method Ziegler-Nichols (ZN), gain-phase margin, Root Locus, Minimum Variance dan Gain Scheduling however these methods are not optimal to control systems that nonlinear and have high-orde, in addition, some methods relative hard. To solve those obstacles, particle swarm optimization (PSO) algorithm is proposed to get optimal Kp, Ki and Kd. PSO is proposed because PSO has convergent result and not require many iterations. On this research, PID controller is applied on AVR (Automatic Voltage Regulator). Based on result of analyzing transient, stability Root Locus and frequency response, performance of PID controller is better than Ziegler-Nichols.

  7. A gain-control theory of binocular combination.

    Science.gov (United States)

    Ding, Jian; Sperling, George

    2006-01-24

    In binocular combination, light images on the two retinas are combined to form a single "cyclopean" perceptual image, in contrast to binocular rivalry which occurs when the two eyes have incompatible ("rivalrous") inputs and only one eye;s stimulus is perceived. We propose a computational theory for binocular combination with two basic principles of interaction: in every spatial neighborhood, each eye (i) exerts gain control on the other eye's signal in proportion to the contrast energy of its own input and (ii) additionally exerts gain control on the other eye's gain control. For stimuli of ordinary contrast, when either eye is stimulated alone, the predicted cyclopean image is the same as when both eyes are stimulated equally, coinciding with an easily observed property of natural vision. The gain-control theory is contrast dependent: Very low-contrast stimuli to the left- and right-eye add linearly to form the predicted cyclopean image. The intrinsic nonlinearity manifests itself only as contrast increases. To test the theory more precisely, a horizontal sine wave grating of 0.68 cycles per degree is presented to each eye. The gratings differ in contrast and phase. The predicted (and perceived) cyclopean grating also is a sine wave; its apparent phase indicates the relative contribution of the two eyes to the cyclopean image. For 48 measured combinations of phase and contrast, the theory with only one estimated parameter accounts for 95% of the variance of the data. Therefore, a simple, robust, physiologically plausible gain-control theory accurately describes an early stage of binocular combination.

  8. Automatic control study of the icing research tunnel refrigeration system

    Science.gov (United States)

    Kieffer, Arthur W.; Soeder, Ronald H.

    1991-01-01

    The Icing Research Tunnel (IRT) at the NASA Lewis Research Center is a subsonic, closed-return atmospheric tunnel. The tunnel includes a heat exchanger and a refrigeration plant to achieve the desired air temperature and a spray system to generate the type of icing conditions that would be encountered by aircraft. At the present time, the tunnel air temperature is controlled by manual adjustment of freon refrigerant flow control valves. An upgrade of this facility calls for these control valves to be adjusted by an automatic controller. The digital computer simulation of the IRT refrigeration plant and the automatic controller that was used in the simulation are discussed.

  9. Inhibition of bradycardia pacing caused by far-field atrial sensing in a third-generation cardioverter defibrillator with an automatic gain feature.

    Science.gov (United States)

    Curwin, J H; Roelke, M; Ruskin, J N

    1996-01-01

    The diagnostic accuracy of implantable cardioverter defibrillators may be improved by automatically adjusting gain algorithms, which in general reduce the likelihood of oversensing while maintaining the ability to detect the low amplitude signals associated with ventricular fibrillation. We present a patient with a third-generation device who developed prolonged ventricular asystole arising as a complication of the automatic gain feature. During asystole the device automatically increased sensitivity in order to prevent undersensing of ventricular fibrillation, which in this case resulted in far-field sensing of atrial activity and inhibition of ventricular pacing.

  10. Gain Scheduling of PID Controller Based on Fuzzy Systems

    Directory of Open Access Journals (Sweden)

    Singh Sandeep

    2016-01-01

    Full Text Available This paper aims to utilize fuzzy rules and reasoning to determine the controller parameters and the PID controller generates the control signal. The objective of this study is to simulate the proposed scheme on various processes and arrive at results providing better response of the system when compared with best industrial auto-tuning technique: Ziegler-Nichols. The proposed scheme is based upon the Ultimate Gain (Ku and the Period (Tu of the system. The error and rate of change in error gains are tuned manually to get the desired response using LabVIEW. This can also be done with various optimization techniques. A thumb rule for choosing the ranges for Kc, Kd and Ki has been obtained experimentally.

  11. An automatic redesign approach for restructurable control systems

    Science.gov (United States)

    Looze, D. P.; Weiss, J. L.; Eterno, J. S.; Barrett, N. M.

    1985-01-01

    This paper presents an approach to the automatic redesign of flight control systems for aircraft that have suffered one or more control element failures. The procedure is based on Linear Quadratic design techniques, and produces a control system that maximizes a measure of feedback system performance subject to a bandwidth constraint.

  12. Structured, Gain-Scheduled Control of Wind Turbines

    DEFF Research Database (Denmark)

    Adegas, Fabiano Daher

    2013-01-01

    control developments, which contributes to the analysis and design of wind turbines in an integrated aeroservoelastic process. From a control point of view, a wind turbine is a challenging system since the wind, which is the energy source driving the machine, is a poorly known disturbance. Additionally......) control framework. The modeling and design procedures allow gain-scheduling to compensate for plant non-linearities and reconfiguration of the controller in face of faults on sensors and actuators of the system. Stability and performance in closed-loop are measured in terms of induced L2-norm....... The procedures are appealing to solve some of the practical wind turbine control problems because the controller structure can be chosen arbitrarily, and the resulting controllers are simple to implement online, requiring low data storage and simple math operations. The modeling procedures also allow...

  13. Fitts' law with an isometric controller: effects of order of control and control-display gain.

    Science.gov (United States)

    Kantowitz, B H; Elvers, G C

    1988-03-01

    Twenty-four male subjects performed a discrete positioning task using an isometric controller. Two levels of order of control (position and velocity) were factorially crossed with two levels of control-display gain. Fitts' law functions were found for each of the four conditions. The velocity control conditions had significantly steeper slopes than the corresponding position control conditions, but there was no main effect for gain. A predicted interaction between control-display gain and order of control was found, indicating that the relative benefit of high gain is greater for velocity control than for position control. The reaction time (RT) regression lines had steeper negative slopes than those attained by Jagacinski, Repperger, Moran, Ward, and Glass (1980), who used an isotonic controller. This is in agreement with the results of Falkenberg and Newell (1980), who found that as average velocity increases, RT decreases. The components of Fitts' law were investigated, and this showed that the RT finding was due to the amplitude of the target, which covaried with average velocity, but was not due to the width.

  14. Evolutionary game dynamics of controlled and automatic decision-making

    Science.gov (United States)

    Toupo, Danielle F. P.; Strogatz, Steven H.; Cohen, Jonathan D.; Rand, David G.

    2015-07-01

    We integrate dual-process theories of human cognition with evolutionary game theory to study the evolution of automatic and controlled decision-making processes. We introduce a model in which agents who make decisions using either automatic or controlled processing compete with each other for survival. Agents using automatic processing act quickly and so are more likely to acquire resources, but agents using controlled processing are better planners and so make more effective use of the resources they have. Using the replicator equation, we characterize the conditions under which automatic or controlled agents dominate, when coexistence is possible and when bistability occurs. We then extend the replicator equation to consider feedback between the state of the population and the environment. Under conditions in which having a greater proportion of controlled agents either enriches the environment or enhances the competitive advantage of automatic agents, we find that limit cycles can occur, leading to persistent oscillations in the population dynamics. Critically, however, these limit cycles only emerge when feedback occurs on a sufficiently long time scale. Our results shed light on the connection between evolution and human cognition and suggest necessary conditions for the rise and fall of rationality.

  15. Humanoid Walking Robot: Modeling, Inverse Dynamics, and Gain Scheduling Control

    Directory of Open Access Journals (Sweden)

    Elvedin Kljuno

    2010-01-01

    Full Text Available This article presents reference-model-based control design for a 10 degree-of-freedom bipedal walking robot, using nonlinear gain scheduling. The main goal is to show concentrated mass models can be used for prediction of the required joint torques for a bipedal walking robot. Relatively complicated architecture, high DOF, and balancing requirements make the control task of these robots difficult. Although linear control techniques can be used to control bipedal robots, nonlinear control is necessary for better performance. The emphasis of this work is to show that the reference model can be a bipedal walking model with concentrated mass at the center of gravity, which removes the problems related to design of a pseudo-inverse system. Another significance of this approach is the reduced calculation requirements due to the simplified procedure of nominal joint torques calculation. Kinematic and dynamic analysis is discussed including results for joint torques and ground force necessary to implement a prescribed walking motion. This analysis is accompanied by a comparison with experimental data. An inverse plant and a tracking error linearization-based controller design approach is described. We propose a novel combination of a nonlinear gain scheduling with a concentrated mass model for the MIMO bipedal robot system.

  16. Robust Fallback Scheme for the Danish Automatic Voltage Control System

    DEFF Research Database (Denmark)

    Qin, Nan; Dmitrova, Evgenia; Lund, Torsten;

    2015-01-01

    This paper proposes a fallback scheme for the Danish automatic voltage control system. It will be activated in case of the local station loses telecommunication to the control center and/or the local station voltage violates the acceptable operational limits. It cuts in/out switchable and tap-abl...

  17. Automatic Design of a Maglev Controller in State Space

    Science.gov (United States)

    1991-12-01

    conventional trains with steel wheels on steel rails. Several experimen- tal maglev systems in Germany and Japan have demonstrated that this mode of...Design of a Maglev Controller in State Space Feng Zhao Richard Thornton Abstract We describe the automatic synthesis of a global nonlinear controller for...the global switching points of the controller is presented. The synthesized control system can stabilize the maglev vehicle with large initial displace

  18. Automatic control system design of laser interferometer

    Science.gov (United States)

    Lu, Qingjie; Li, Chunjie; Sun, Hao; Ren, Shaohua; Han, Sen

    2015-10-01

    There are a lot of shortcomings with traditional optical adjustment in interferometry, such as low accuracy, time-consuming, labor-intensive, uncontrollability, and bad repetitiveness, so we treat the problem by using wireless remote control system. Comparing to the traditional method, the effect of vibration and air turbulence will be avoided. In addition the system has some peculiarities of low cost, high reliability and easy operation etc. Furthermore, the switching between two charge coupled devices (CCDs) can be easily achieved with this wireless remote control system, which is used to collect different images. The wireless transmission is achieved by using Radio Frequency (RF) module and programming the controller, pulse width modulation (PWM) of direct current (DC) motor, real-time switching of relay and high-accuracy displacement control of FAULHABER motor are available. The results of verification test show that the control system has good stability with less than 5% packet loss rate, high control accuracy and millisecond response speed.

  19. Gain Scheduling Control of an Islanded Microgrid Voltage

    Directory of Open Access Journals (Sweden)

    Haritza Camblong

    2014-07-01

    Full Text Available The aim of this research study has been to design a gain scheduling (GS digital controller in order to control the voltage of an islanded microgrid in the presence of fast varying loads (FVLs, and to compare it to a robust controller. The inverter which feeds the microgrid is connected to it through an inductance-capacitor-inductance (LCL filter. The oscillatory and nonlinear behaviour of the plant is analyzed in the whole operating zone. Afterwards, the design of the controllers which contain two loops in cascade are described. The first loop concerns the current control, while the second is linked to the voltage regulation. Two controllers, one defined as Robust and another one as GS controller, are designed for the two loops, emphasizing in their robustness and their ability to damp the oscillatory plant behaviour. To finish, some simulations are carried out to study and compare the two kinds of controllers in different operating points. The results show that both controllers damp the oscillatory behaviour of the plant in closed loop (CL, and that the GS controller ensures a better rejection of current disturbances from FVLs.

  20. Flight Investigation of a Normal-Acceleration Automatic Longitudinal Control System in a Fighter Airplane

    Science.gov (United States)

    Sjoberg, S. A.; Russell, Walter R.; Alford, William L.

    1958-01-01

    A flight investigation was made to obtain experimental information on the handling qualities of a normal-acceleration type of automatic longitudinal control system. The control system was installed in a subsonic fighter-type airplane. In hands-off (stick-free) flight the normal-acceleration control system attempted to regulate the normal acceleration to a constant value which is dependent on the automatic-control-system trim setting. In maneuvering flight a given pilot's stick deflection produced a proportional change in normal acceleration, the change in acceleration being independent of flight condition. A small side-located controller stick was used by the pilot to introduce signals into the automatic control system. In the flight program emphasis was placed on the acceleration-limiting capabilities of the control system. The handling qualities were investigated in maneuvers such as slow and rapid pull-ups and turns and also in flight operations such as cruising, stalls, landings, aerobatics, and air-to-air tracking. Good acceleration limiting was obtained with the normal-acceleration control system by limiting the magnitude of the input signal that the pilot could introduce into the control system. The same values of control-system gain settings could be used from an acceleration-limiting stand-point at both 10,000 and 30,000 feet for the complete speed range of the airplane. The response characteristics of the airplane-control system combination were also satisfactory at both high and low altitude with these same values of control-system gain setting. In the pilot's opinion, the normal-acceleration control system provided good stability and control characteristics in flight operations such as cruising, stalls, landings, aerobatics, and air-to-air tracking.

  1. 5th International Conference on Electrical Engineering and Automatic Control

    CERN Document Server

    Yao, Yufeng

    2016-01-01

    On the basis of instrument electrical and automatic control system, the 5th International Conference on Electrical Engineering and Automatic Control (CEEAC) was established at the crossroads of information technology and control technology, and seeks to effectively apply information technology to a sweeping trend that views control as the core of intelligent manufacturing and life. This book takes a look forward into advanced manufacturing development, an area shaped by intelligent manufacturing. It highlights the application and promotion of process control represented by traditional industries, such as the steel industry and petrochemical industry; the technical equipment and system cooperative control represented by robot technology and multi-axis CNC; and the control and support of emerging process technologies represented by laser melting and stacking, as well as the emerging industry represented by sustainable and intelligent life. The book places particular emphasis on the micro-segments field, such as...

  2. Neural Network Control-Based Drive Design of Servomotor and Its Application to Automatic Guided Vehicle

    Directory of Open Access Journals (Sweden)

    Ming-Shyan Wang

    2015-01-01

    Full Text Available An automatic guided vehicle (AGV is extensively used for productions in a flexible manufacture system with high efficiency and high flexibility. A servomotor-based AGV is designed and implemented in this paper. In order to steer the AGV to go along a predefined path with corner or arc, the conventional proportional-integral-derivative (PID control is used in the system. However, it is difficult to tune PID gains at various conditions. As a result, the neural network (NN control is considered to assist the PID control for gain tuning. The experimental results are first provided to verify the correctness of the neural network plus PID control for 400 W-motor control system. Secondly, the AGV includes two sets of the designed motor systems and CAN BUS transmission so that it can move along the straight line and curve paths shown in the taped videos.

  3. Adaptive gain control for spike-based map communication in a neuromorphic vision system.

    Science.gov (United States)

    Meng, Yicong; Shi, Bertram E

    2008-06-01

    To support large numbers of model neurons, neuromorphic vision systems are increasingly adopting a distributed architecture, where different arrays of neurons are located on different chips or processors. Spike-based protocols are used to communicate activity between processors. The spike activity in the arrays depends on the input statistics as well as internal parameters such as time constants and gains. In this paper, we investigate strategies for automatically adapting these parameters to maintain a constant firing rate in response to changes in the input statistics. We find that under the constraint of maintaining a fixed firing rate, a strategy based upon updating the gain alone performs as well as an optimal strategy where both the gain and the time constant are allowed to vary. We discuss how to choose the time constant and propose an adaptive gain control mechanism whose operation is robust to changes in the input statistics. Our experimental results on a mobile robotic platform validate the analysis and efficacy of the proposed strategy.

  4. Evaluation of automatic time gain compensated in-vivo ultrasound sequences

    DEFF Research Database (Denmark)

    Axelsen, Martin Christian; Røeboe, Kristian Frostholm; Hemmsen, Martin Christian;

    2010-01-01

    Ultrasound imaging is increasingly being used in applications such as surgery, anesthesia and urology, where the users are not trained radiologists. User studies indicate that these users rarely adjust the controls of the ultrasound scanner. This project presents a preliminary evaluation of a new...

  5. Automatic control of biomass gasifiers using fuzzy inference systems

    Energy Technology Data Exchange (ETDEWEB)

    Sagues, C. [Universidad de Zaragoza (Spain). Dpto. de Informatica e Ingenieria de Sistemas; Garcia-Bacaicoa, P.; Serrano, S. [Universidad de Zaragoza (Spain). Dpto. de Ingenieria Quimica y Medio Ambiente

    2007-03-15

    A fuzzy controller for biomass gasifiers is proposed. Although fuzzy inference systems do not need models to be tuned, a plant model is proposed which has turned out very useful to prove different combinations of membership functions and rules in the proposed fuzzy control. The global control scheme is shown, including the elements to generate the set points for the process variables automatically. There, the type of biomass and its moisture content are the only data which need to be introduced to the controller by a human operator at the beginning of operation to make it work autonomously. The advantages and good performance of the fuzzy controller with the automatic generation of set points, compared to controllers utilising fixed parameters, are demonstrated. (author)

  6. Automatic control of biomass gasifiers using fuzzy inference systems.

    Science.gov (United States)

    Sagüés, C; García-Bacaicoa, P; Serrano, S

    2007-03-01

    A fuzzy controller for biomass gasifiers is proposed. Although fuzzy inference systems do not need models to be tuned, a plant model is proposed which has turned out very useful to prove different combinations of membership functions and rules in the proposed fuzzy control. The global control scheme is shown, including the elements to generate the set points for the process variables automatically. There, the type of biomass and its moisture content are the only data which need to be introduced to the controller by a human operator at the beginning of operation to make it work autonomously. The advantages and good performance of the fuzzy controller with the automatic generation of set points, compared to controllers utilising fixed parameters, are demonstrated.

  7. Development of Automatic Remote Exposure Controller for Gamma Radiography

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Gwang Tae; Shin, Jin Seong; Kim, Dong Eun; Song, Jung Ho; Choo, Seung Hwan; Chang, Hong Keun [Korea Industrial Testing Co., Ltd., Seoul (Korea, Republic of)

    2002-10-15

    Recently, gamma radiographic equipment have been used about 1,000 sets manually and operated by about 2,500 persons in Korea. In order for a radiography to work effectively with avoiding any hazard of the high level radiation from the source, many field workers have expected developing a wireless automatic remote exposure controller. The KlTCO research team has developed an automatic remote exposure controller that can regulate the speed of 0.4{approx}1.2m/s by BLDC motor of 24V 200W which has output of 54 kgf{center_dot}, suitable torque and safety factor for the work. And the developed automatic remote exposure controller can control rpm of motor, pigtail position by photo-sensor and exposure time by timer to RF sensor. Thus, the developed equipment is expected that the unit can be used in many practical applications with benefits in economical advantage to combine the use of both automatic and manual type because attachment is possible existent manual remote exposure controller, AC and DC combined use

  8. Robust, Gain-Scheduled Control of Wind Turbines

    DEFF Research Database (Denmark)

    Østergaard, Kasper Zinck

    Wind turbines are today large and efficient machines, which are combined into wind farms operating on par with conventional power plants. When looking back, this is significantly different from the status only a few years ago, when wind turbines were sold mainly to private people. This change...... in turbine owners has resulted in a new focus on operational reliability instead of turbine size. This research deals with investigating model-based gain-scheduling control of wind turbines by use of linear parameter varying (LPV) methods. The numerical challenges grow quickly with the model size...

  9. Semi-automatic aircraft control system

    Science.gov (United States)

    Gilson, Richard D. (Inventor)

    1978-01-01

    A flight control type system which provides a tactile readout to the hand of a pilot for directing elevator control during both approach to flare-out and departure maneuvers. For altitudes above flare-out, the system sums the instantaneous coefficient of lift signals of a lift transducer with a generated signal representing ideal coefficient of lift for approach to flare-out, i.e., a value of about 30% below stall. Error signals resulting from the summation are read out by the noted tactile device. Below flare altitude, an altitude responsive variation is summed with the signal representing ideal coefficient of lift to provide error signal readout.

  10. Image Control In Automatic Welding Vision System

    Science.gov (United States)

    Richardson, Richard W.

    1988-01-01

    Orientation and brightness varied to suit welding conditions. Commands from vision-system computer drive servomotors on iris and Dove prism, providing proper light level and image orientation. Optical-fiber bundle carries view of weld area as viewed along axis of welding electrode. Image processing described in companion article, "Processing Welding Images for Robot Control" (MFS-26036).

  11. Study on automatic tuning of ship`s PID regulators; Hakuyo seigyo system no gain jido chosei ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Nakatani, T. [Toyama Mercantile Marine College, Toyama (Japan); Otsu, K.; Moriyoshi, N. [Tokyo Univ. of Mercantile Marine, Tokyo (Japan); Okazaki, T. [Nagoya Institute of Technology, Nagoya (Japan)

    1996-12-31

    Proportional, integral and derivative (PID) controls are used for a steering system and a main engine control unit installed in a vessel. Among them, this paper describes effectiveness of a PID gain tuning method using a limit cycle by means of relay control which is safer and simpler than conventional limit sensitivity methods. The present method was applied to an actual marine control system to conduct an actual vessel experiment. As a result of applying the method to a bow azimuth control system using a rudder, a new azimuth setting was set with an overshoot of 1.6 degrees in a ten-degree azimuth changing experiment. With respect to direction maintaining steering performance, the present method was capable of controlling the direction at a speed loss to about 80% of the ship`s autopilot. As a result of applying the method to a bow azimuth control system using a bow thruster, direction maintaining and changing control was realized in a low speed range in which rudder effect is lost. As a result of applying it to a main engine governor system and performing control of main engine rotation speed, it was found possible to derive control gains in a safe state without applying an excessive load to the main engine both under load and no load conditions. 14 refs., 8 figs., 11 tabs.

  12. Lesion strength control by automatic temperature guided retinal photocoagulation

    Science.gov (United States)

    Schlott, Kerstin; Koinzer, Stefan; Baade, Alexander; Birngruber, Reginald; Roider, Johann; Brinkmann, Ralf

    2016-09-01

    Laser photocoagulation is an established treatment for a variety of retinal diseases. However, when using the same irradiation parameter, the size and strength of the lesions are unpredictable due to unknown inter- and intraindividual optical properties of the fundus layers. The aim of this work is to investigate a feedback system to generate desired lesions of preselectable strengths by automatically controlling the irradiation time. Optoacoustics were used for retinal temperature monitoring. A 532-nm continuous wave Nd:YAG laser was used for photocoagulation. A 75-ns/523-nm Q-switched Nd:YLF laser simultaneously excited temperature-dependent pressure transients, which were detected at the cornea by an ultrasonic transducer embedded in a contact lens. The temperature data were analyzed during the irradiation by a LabVIEW routine. The treatment laser was switched off automatically when the required lesion strength was achieved. Five different feedback control algorithms for different lesion sizes were developed and tested on rabbits in vivo. With a laser spot diameter of 133 μm, five different lesion types with ophthalmoscopically visible diameters ranging mostly between 100 and 200 μm, and different appearances were achieved by automatic exposure time control. The automatically controlled lesions were widely independent of the treatment laser power and the retinal pigmentation.

  13. Supplement to Comparison of automatic control systems

    Science.gov (United States)

    Oppelt, W

    1941-01-01

    This analysis deals with the indirect regulator, wherefrom the behavior of the direct regulator is deduced as a limiting case. The prime mover is looked upon as "independent of the load": a change in the adjusting power (to be applied) for the control link (as, for example, in relation to the adjusting path (eta) with pressure valves or the rudder of vessels) does not modify the actions of the prime mover. Mass forces and friction are discounted; "clearance" also is discounted in the transmission links of the regulator.

  14. Randomized algorithms in automatic control and data mining

    CERN Document Server

    Granichin, Oleg; Toledano-Kitai, Dvora

    2015-01-01

    In the fields of data mining and control, the huge amount of unstructured data and the presence of uncertainty in system descriptions have always been critical issues. The book Randomized Algorithms in Automatic Control and Data Mining introduces the readers to the fundamentals of randomized algorithm applications in data mining (especially clustering) and in automatic control synthesis. The methods proposed in this book guarantee that the computational complexity of classical algorithms and the conservativeness of standard robust control techniques will be reduced. It is shown that when a problem requires "brute force" in selecting among options, algorithms based on random selection of alternatives offer good results with certain probability for a restricted time and significantly reduce the volume of operations.

  15. Computer program for automatic generation of BWR control rod patterns

    Energy Technology Data Exchange (ETDEWEB)

    Taner, M.S.; Levine, S.H.; Hsia, M.Y. (Pennsylvania State Univ., University Park (United States))

    1990-01-01

    A computer program named OCTOPUS has been developed to automatically determine a control rod pattern that approximates some desired target power distribution as closely as possible without violating any thermal safety or reactor criticality constraints. The program OCTOPUS performs a semi-optimization task based on the method of approximation programming (MAP) to develop control rod patterns. The SIMULATE-E code is used to determine the nucleonic characteristics of the reactor core state.

  16. LPV gain-scheduled control of SCR aftertreatment systems

    Science.gov (United States)

    Meisami-Azad, Mona; Mohammadpour, Javad; Grigoriadis, Karolos M.; Harold, Michael P.; Franchek, Matthew A.

    2012-01-01

    Hydrocarbons, carbon monoxide and some of other polluting emissions produced by diesel engines are usually lower than those produced by gasoline engines. While great strides have been made in the exhaust aftertreatment of vehicular pollutants, the elimination of nitrogen oxide (NO x ) from diesel vehicles is still a challenge. The primary reason is that diesel combustion is a fuel-lean process, and hence there is significant unreacted oxygen in the exhaust. Selective catalytic reduction (SCR) is a well-developed technology for power plants and has been recently employed for reducing NO x emissions from automotive sources and in particular, heavy-duty diesel engines. In this article, we develop a linear parameter-varying (LPV) feedforward/feedback control design method for the SCR aftertreatment system to decrease NO x emissions while keeping ammonia slippage to a desired low level downstream the catalyst. The performance of the closed-loop system obtained from the interconnection of the SCR system and the output feedback LPV control strategy is then compared with other control design methods including sliding mode, and observer-based static state-feedback parameter-varying control. To reduce the computational complexity involved in the control design process, the number of LPV parameters in the developed quasi-LPV (qLPV) model is reduced by applying the principal component analysis technique. An LPV feedback/feedforward controller is then designed for the qLPV model with reduced number of scheduling parameters. The designed full-order controller is further simplified to a first-order transfer function with a parameter-varying gain and pole. Finally, simulation results using both a low-order model and a high-fidelity and high-order model of SCR reactions in GT-POWER interfaced with MATLAB/SIMULINK illustrate the high NO x conversion efficiency of the closed-loop SCR system using the proposed parameter-varying control law.

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

    Science.gov (United States)

    Vestergaard, Mikkel; Berg, Rune W

    2015-02-25

    When using muscles, the precision with which force is delivered is as important as the delivery of force itself. Force is regulated by both the number of recruited motoneurons and their spike frequency. While it is known that the recruitment is ordered to reduce variability in force, it remains 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 regulated on a subsecond timescale, it is also adjusted to minimize variability. The modulation is likely achieved via an expansive nonlinearity between spike rate and membrane potential with inhibition having a divisive influence. These findings reveal a versatile mechanism of modulating neuronal sensitivity and suggest that such modulation is fundamentally linked to optimization.

  18. 2011 International Conference in Electrics, Communication and Automatic Control Proceedings

    CERN Document Server

    2012-01-01

    This two-volume set contains the very latest, cutting-edge material in electrics, communication and automatic control. As a vital field of research that is highly relevant to current developments in a number of technological domains, the subjects it covers include micro-electronics and integrated circuit control, signal processing technology, next-generation network infrastructure, wireless communication and scientific instruments. The aim of the International Conference in Electrics, Communication and Automatic Control, held in Chongqing, China, in June 2011 was to provide a valuable inclusive platform for researchers, engineers, academicians and industrial professionals from all over the world to share their research results with fellow scientists in the sector. The call for papers netted well over 600 submissions, of which 224 were selected for presentation. This fully peer-reviewed collection of papers from the conference can be viewed as a single-source compendium of the latest trends and techniques in t...

  19. A method for closed loop automatic tuning of PID controllers

    Directory of Open Access Journals (Sweden)

    Tor S. Schei

    1992-07-01

    Full Text Available A simple method for the automatic tuning of PID controllers in closed loop is proposed. A limit cycle is generated through a nonlinear feedback path from the process output to the controller reference signal. The frequency of this oscillation is above the crossover frequency and below the critical frequency of the loop transfer function. The amplitude and frequency of the oscillation are estimated and the control parameters are adjusted iteratively such that the closed loop transfer function from the controller reference to the process output attains a specified amplitude at the oscillation frequency.

  20. Automatic control systems satisfying certain general criterions on transient behavior

    Science.gov (United States)

    Boksenbom, Aaron S; Hood, Richard

    1952-01-01

    An analytic method for the design of automatic controls is developed that starts from certain arbitrary criterions on the behavior of the controlled system and gives those physically realizable equations that the control system can follow in order to realize this behavior. The criterions used are developed in the form of certain time integrals. General results are shown for systems of second order and of any number of degrees of freedom. Detailed examples for several cases in the control of a turbojet engine are presented.

  1. Evaluation Performance of IC Engine: Linear Tunable Gain Computed Torque Controller vs. Sliding Mode Controller

    Directory of Open Access Journals (Sweden)

    Shahnaz Tayebi Haghighi

    2013-05-01

    Full Text Available Design a nonlinear controller for second order nonlinear uncertain dynamical systems (e.g., internal combustion engine is one of the most important challenging works. This paper focuses on the comparative study between two important nonlinear controllers namely; computed torque controller (CTC and sliding mode controller (SMC and applied to internal combustion (IC engine in presence of uncertainties. In order to provide high performance nonlinear methodology, sliding mode controller and computed torque controller are selected. Pure SMC and CTC can be used to control of partly known nonlinear dynamic parameters of IC engine. Pure sliding mode controller and computed torque controller have difficulty in handling unstructured model uncertainties. To solve this problem applied linear error-based tuning method to sliding mode controller and computed torque controller for adjusting the sliding surface gain (λ and linear inner loop gain (K. Since the sliding surface gain (λ and linear inner loop gain (K are adjusted by linear error-based tuning method. In this research new λ and new K are obtained by the previous λ and K multiple gains updating factor(α. The results demonstrate that the error-based linear SMC and CTC are model-based controllers which works well in certain and uncertain system. These controllers have acceptable performance in presence of uncertainty.

  2. Controlled versus automatic processes: which is dominant to safety? The moderating effect of inhibitory control.

    Science.gov (United States)

    Xu, Yaoshan; Li, Yongjuan; Ding, Weidong; Lu, Fan

    2014-01-01

    This study explores the precursors of employees' safety behaviors based on a dual-process model, which suggests that human behaviors are determined by both controlled and automatic cognitive processes. Employees' responses to a self-reported survey on safety attitudes capture their controlled cognitive process, while the automatic association concerning safety measured by an Implicit Association Test (IAT) reflects employees' automatic cognitive processes about safety. In addition, this study investigates the moderating effects of inhibition on the relationship between self-reported safety attitude and safety behavior, and that between automatic associations towards safety and safety behavior. The results suggest significant main effects of self-reported safety attitude and automatic association on safety behaviors. Further, the interaction between self-reported safety attitude and inhibition and that between automatic association and inhibition each predict unique variances in safety behavior. Specifically, the safety behaviors of employees with lower level of inhibitory control are influenced more by automatic association, whereas those of employees with higher level of inhibitory control are guided more by self-reported safety attitudes. These results suggest that safety behavior is the joint outcome of both controlled and automatic cognitive processes, and the relative importance of these cognitive processes depends on employees' individual differences in inhibitory control. The implications of these findings for theoretical and practical issues are discussed at the end.

  3. Controlled versus automatic processes: which is dominant to safety? The moderating effect of inhibitory control.

    Directory of Open Access Journals (Sweden)

    Yaoshan Xu

    Full Text Available This study explores the precursors of employees' safety behaviors based on a dual-process model, which suggests that human behaviors are determined by both controlled and automatic cognitive processes. Employees' responses to a self-reported survey on safety attitudes capture their controlled cognitive process, while the automatic association concerning safety measured by an Implicit Association Test (IAT reflects employees' automatic cognitive processes about safety. In addition, this study investigates the moderating effects of inhibition on the relationship between self-reported safety attitude and safety behavior, and that between automatic associations towards safety and safety behavior. The results suggest significant main effects of self-reported safety attitude and automatic association on safety behaviors. Further, the interaction between self-reported safety attitude and inhibition and that between automatic association and inhibition each predict unique variances in safety behavior. Specifically, the safety behaviors of employees with lower level of inhibitory control are influenced more by automatic association, whereas those of employees with higher level of inhibitory control are guided more by self-reported safety attitudes. These results suggest that safety behavior is the joint outcome of both controlled and automatic cognitive processes, and the relative importance of these cognitive processes depends on employees' individual differences in inhibitory control. The implications of these findings for theoretical and practical issues are discussed at the end.

  4. Accurately control and flatten gain spectrum of L-band erbium doped fiber amplifier based on suitable gain-clamping

    Science.gov (United States)

    Yang, Jiuru; Meng, Xiangyu; Liu, Chunyu

    2016-04-01

    The increasing traffic with dynamic nature requires the applications of gain-clamped L-band erbium-doped fiber amplifier (EDFA). However, the weak or over clamping may lead the unexpected gain-compression and flatness-worsening. In this article, to enhance practicality, we modify the partly gain-clamping configuration and utilize a pair of C-band fiber Bragg gratings (FBGs) to non-uniformly compress the gain spectrum of L-band. Through a comprehensive test and comparison, the suitable gain-clamping region for the amplified signals is found, and the gain in L-band is accurately controlled and flattened under the matched central wavelength of FBGs. The experimental results show that, our designed L-band EDFA achieves a trade-off among the output gain, flatness and stability. The ±0.44 dB flatness and 20.2 dB average gain are together obtained in the range of 1570-1610 nm, with the ±0.1 dB stability of signals in over 30 dBm dynamic range.

  5. On controllability of neuronal networks with constraints on the average of control gains.

    Science.gov (United States)

    Tang, Yang; Wang, Zidong; Gao, Huijun; Qiao, Hong; Kurths, Jürgen

    2014-12-01

    Control gains play an important role in the control of a natural or a technical system since they reflect how much resource is required to optimize a certain control objective. This paper is concerned with the controllability of neuronal networks with constraints on the average value of the control gains injected in driver nodes, which are in accordance with engineering and biological backgrounds. In order to deal with the constraints on control gains, the controllability problem is transformed into a constrained optimization problem (COP). The introduction of the constraints on the control gains unavoidably leads to substantial difficulty in finding feasible as well as refining solutions. As such, a modified dynamic hybrid framework (MDyHF) is developed to solve this COP, based on an adaptive differential evolution and the concept of Pareto dominance. By comparing with statistical methods and several recently reported constrained optimization evolutionary algorithms (COEAs), we show that our proposed MDyHF is competitive and promising in studying the controllability of neuronal networks. Based on the MDyHF, we proceed to show the controlling regions under different levels of constraints. It is revealed that we should allocate the control gains economically when strong constraints are considered. In addition, it is found that as the constraints become more restrictive, the driver nodes are more likely to be selected from the nodes with a large degree. The results and methods presented in this paper will provide useful insights into developing new techniques to control a realistic complex network efficiently.

  6. Automatic control unit for A neutron diffraction crystal spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Adib, M.; Abbas, Y.; Mostafa, M.; Hamouda, I.

    1982-01-01

    An automatic transistorized unit has been designed and constructed to control the operation of the double axis crystal spectrometer installed in front of one of the horizontal channels of the ET-RR-1 reactor. The function of the automatic unit is to store the diffracted neutrons at a certain angle with respect to the direction of the incident neutron beam in a selected channel of a 1024-multichannel analyzer for a certain preadjusted time period. AT the end of this time period the unit rotates the spectrometer's arm to another angle, selects the next channel of the MCA and provides the measurement of the diffracted neutron for the same time period. Such a sequence is repeated automatically over all angles required for the neutron diffraction pattern of the sample under investigation. As a result, the stored information at the MCA provides the neutron diffraction pattern as a function of channel number, where each channel corresponds to a certain scattering angle. The stored distribution at MCA can be obtained through the analyzer read out unit. The designed automatic unit has the possibility of providing the neutron diffraction pattern using a 6-digit scaler and a printer.

  7. Development of a digital automatic control law for steep glideslope capture and flare

    Science.gov (United States)

    Halyo, N.

    1977-01-01

    A longitudinal digital guidance and control law for steep glideslopes using MLS (Microwave Landing System) data is developed for CTOL aircraft using modern estimation and control techniques. The control law covers the final approach phases of glideslope capture, glideslope tracking, and flare to touchdown for automatic landings under adverse weather conditions. The control law uses a constant gain Kalman filter to process MLS and body-mounted accelerometer data to form estimates of flight path errors and wind velocities including wind shear. The flight path error estimates and wind estimates are used for feedback in generating control surface commands. Results of a digital simulation of the aircraft dynamics and the guidance and control law are presented for various wind conditions.

  8. Research on Fuzzy Control for Automatic Transmission of Tracked Vehicles

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A principle of fuzzy control for tracked vehicles is proposed to make its automatic transmission system be able to adapt complex running conditions, and a model of its power train is established to be used in simulation. Based on the fuzzy control method, a fuzzy shift control system composed of a basic shift strategy and a fuzzy modification module is developed to improve the dynamic characteristics and cross-country maneuverability. Simulation results show that the fuzzy shift strategy can improve the shift quality under manifold driving conditions and avoid cycled shift effectively. Therefore,the proposed fuzzy shift strategies are proved to be feasible and practicable.

  9. Simulation results of automatic restructurable flight control system concepts

    Science.gov (United States)

    Weiss, J. L.; Looze, D. P.; Eterno, J. S.; Ostroff, A.

    1986-01-01

    The restructurable flight control system (RFCS) described by Weiss et al. (1986) is reviewed, and several results of an extensive six degrees of freedom nonlinear simulation of several aspects of this system are reported. It is concluded that the nontraditional use of standard control surfaces in a nominal feedback control system to spread control authority among many redundant control elements provides a significant amount of fault tolerance without any use of restructuring techniques. The use of new feedback gains alone following a failure can provide significantly improved recovery as long as the control elements remain within their travel limits and as long as uncertainty about the failure identity is properly handled. The use of the feed-forward trim solution in conjunction with redesigned feedback gains allows recovery to take place even when significant control saturation occurs.

  10. POWER CONTROL AND ANTENNA GAIN OPTIMIZATION DURING WIMAX HANDOVER

    Directory of Open Access Journals (Sweden)

    P.P. Edwin Winston

    2012-04-01

    Full Text Available Wireless systems have recently been becoming faster and more intelligent. However the high speed access and intelligence make the power consumption of wireless systems high. In the WiMAX system, the MS transmission power is controlled in order to avoid exceeding the BS’s total receiving power from an antenna. Conventional wireless network design has long used base site sectorization and single, omni-directional antennas at the enduser device to serve the communications link, with advanced multi-antenna implementations operators have a new suite of tools to develop the robust wireless networks of the future. Revolutionary multiple antenna techniques at the base station and end-user device, paired with sophisticated signal processing and power consumption control, can dramatically improve the communications link for the most demanding applicationscenarios including heavily obstructed propagation environments and high speed mobility service. This paper presents results of an experimental study, simulation based, directed to determine the optimum transmission power and Antenna gain which influence on the overall handover performance in mobility scenarios, related toWiMAX communications. Based on them, optimal parameter sets can be provided by the network operator to mobile station, to guide its adaptation of the major WiMAX parameters to its speed and network topology and to help the handover decision.

  11. 14 CFR 25.904 - Automatic takeoff thrust control system (ATTCS).

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Automatic takeoff thrust control system... Automatic takeoff thrust control system (ATTCS). Each applicant seeking approval for installation of an engine power control system that automatically resets the power or thrust on the operating engine(s)...

  12. Review on development progress of automatic manual transmissions control

    Institute of Scientific and Technical Information of China (English)

    ALI Amir Ibrahim; QIN Da-tong; ATTIA Nabil Abdulla

    2004-01-01

    In recent years, the sustainable development of automatic manual transmissions (AMTs) control in vehicles is conspicuous. The control applications have grown fast and steadily due to the tremendous progress in power electronics components and the control software that enhance the requirements for delivering higher vehicles performance. AMTs control strategies achieve a reduction in the driveline dynamic oscillations behavior during gear shifting and clutch starting up processes.AMTs future expectations are an increase of torque capacity, more speed ratios and the development of advanced and efficient electronic control systems. This paper concerns with the progressing view of AMTs in the past, today and future, gives an overview of the potential dynamic problems concerned with AMTs and some control strategies used to solve those problems.

  13. MFM Automatic Control System Development for CYCIAE-100

    Institute of Scientific and Technical Information of China (English)

    CAO; Lei; YIN; Zhi-guo; LV; Yin-long; ZHONG; Jun-qing

    2012-01-01

    <正>In order to do the magnetic field measurement (MFM) work for CYCIAE-100, a set of MFM automatic facility has been developed by the cyclotron team at CIAE. 1 Design of project The MFM facility for CYCIAE-100 adopts the method of circular and radial motion to complete the measurement. In circular direction, an open loop control is adopted at hardware level. A kind of arithmetic is compensated to form a virtual closed loop control based on the position signal by angle encoder

  14. Automatic control and tracking of periodic orbits in chaotic systems.

    Science.gov (United States)

    Ando, Hiroyasu; Boccaletti, S; Aihara, Kazuyuki

    2007-06-01

    Based on an automatic feedback adjustment of an additional parameter of a dynamical system, we propose a strategy for controlling periodic orbits of desired periods in chaotic dynamics and tracking them toward the set of unstable periodic orbits embedded within the original chaotic attractor. The method does not require information on the system to be controlled, nor on any reference states for the targets, and it overcomes some of the difficulties encountered by other techniques. Assessments of the method's effectiveness and robustness are given by means of the application of the technique to the stabilization of unstable periodic orbits in both discrete- and continuous-time systems.

  15. Aircraft automatic flight control system with model inversion

    Science.gov (United States)

    Smith, G. A.; Meyer, George

    1990-01-01

    A simulator study was conducted to verify the advantages of a Newton-Raphson model-inversion technique as a design basis for an automatic trajectory control system in an aircraft with highly nonlinear characteristics. The simulation employed a detailed mathematical model of the aerodynamic and propulsion system performance characteristics of a vertical-attitude takeoff and landing tactical aircraft. The results obtained confirm satisfactory control system performance over a large portion of the flight envelope. System response to wind gusts was satisfactory for various plausible combinations of wind magnitude and direction.

  16. Automatic control system generation for robot design validation

    Science.gov (United States)

    Bacon, James A. (Inventor); English, James D. (Inventor)

    2012-01-01

    The specification and drawings present a new method, system and software product for and apparatus for generating a robotic validation system for a robot design. The robotic validation system for the robot design of a robotic system is automatically generated by converting a robot design into a generic robotic description using a predetermined format, then generating a control system from the generic robotic description and finally updating robot design parameters of the robotic system with an analysis tool using both the generic robot description and the control system.

  17. Automatic and controlled processing in the corticocerebellar system.

    Science.gov (United States)

    Ramnani, Narender

    2014-01-01

    During learning, performance changes often involve a transition from controlled processing in which performance is flexible and responsive to ongoing error feedback, but effortful and slow, to a state in which processing becomes swift and automatic. In this state, performance is unencumbered by the requirement to process feedback, but its insensitivity to feedback reduces its flexibility. Many properties of automatic processing are similar to those that one would expect of forward models, and many have suggested that these may be instantiated in cerebellar circuitry. Since hierarchically organized frontal lobe areas can both send and receive commands, I discuss the possibility that they can act both as controllers and controlled objects and that their behaviors can be independently modeled by forward models in cerebellar circuits. Since areas of the prefrontal cortex contribute to this hierarchically organized system and send outputs to the cerebellar cortex, I suggest that the cerebellum is likely to contribute to the automation of cognitive skills, and to the formation of habitual behavior which is resistant to error feedback. An important prerequisite to these ideas is that cerebellar circuitry should have access to higher order error feedback that signals the success or failure of cognitive processing. I have discussed the pathways through which such feedback could arrive via the inferior olive and the dopamine system. Cerebellar outputs inhibit both the inferior olive and the dopamine system. It is possible that learned representations in the cerebellum use this as a mechanism to suppress the processing of feedback in other parts of the nervous system. Thus, cerebellar processes that control automatic performance may be completed without triggering the engagement of controlled processes by prefrontal mechanisms.

  18. Cognitive effort and pupil dilation in controlled and automatic processes

    Science.gov (United States)

    Querino, Emanuel; dos Santos, Lafaiete; Ginani, Giuliano; Nicolau, Eduardo; Miranda, Débora; Romano-Silva, Marco; Malloy-Diniz, Leandro

    2015-01-01

    The Five Digits Test (FDT) is a Stroop paradigm test that aims to evaluate executive functions. It is composed of four parts, two of which are related to automatic and two of which are related to controlled processes. It is known that pupillary diameter increases as the task’s cognitive demand increases. In the present study, we evaluated whether the pupillary diameter could distinguish cognitive effort between automated and controlled cognitive processing during the FDT as the task progressed. As a control task, we used a simple reading paradigm with a similar visual aspect as the FDT. We then divided each of the four parts into two blocks in order to evaluate the differences between the first and second half of the task. Results indicated that, compared to a control task, the FDT required higher cognitive effort for each consecutive part. Moreover, the first half of every part of the FDT induced dilation more than the second. The differences in pupil dilation during the first half of the four FDT parts were statistically significant between the parts 2 and 4 (p=0.023), and between the parts 3 and 4 (p=0.006). These results provide further evidence that cognitive effort and pupil diameter can distinguish controlled from automatic processes.

  19. Design of an optimal SMES for automatic generation control of two-area thermal power system using Cuckoo search algorithm

    Directory of Open Access Journals (Sweden)

    Sabita Chaine

    2015-05-01

    Full Text Available This work presents a methodology adopted in order to tune the controller parameters of superconducting magnetic energy storage (SMES system in the automatic generation control (AGC of a two-area thermal power system. The gains of integral controllers of AGC loop, proportional controller of SMES loop and gains of the current feedback loop of the inductor in SMES are optimized simultaneously in order to achieve a desired performance. Recently proposed intelligent technique based algorithm known as Cuckoo search algorithm (CSA is applied for optimization. Sensitivity and robustness of the tuned gains tested at different operating conditions prove the effectiveness of fast acting energy storage devices like SMES in damping out oscillations in power system when their controllers are properly tuned.

  20. Flexible Joints Robotic Manipulator Control By Adaptive Gain Smooth Sliding Observer-Controller

    Directory of Open Access Journals (Sweden)

    A. FILIPESCU

    2003-12-01

    Full Text Available An adaptive gain sliding observer for uncertain parameter nonlinear systems together with an adaptive gain sliding controller is proposed in this paper. It considered nonlinear, SISO affine systems, with uncertainties in steady-state functions and parameters. A further parameter term, adaptively updated, has been introduced in steady state space model of the controlled system, in order to obtain useful information despite fault detection and isolation. By using of the sliding observer with adaptive gain, the robustness to uncertainties is increased and the parameters adaptively updated can provide useful information in fault detection. Also, the state estimation error is bounded accordingly with bound limits of the uncertainties. The both of them, the sliding adaptive observer and sliding controller are designed to fulfill the attractiveness condition of its corresponding switching surface. An application to a single arm with flexible joint robot is presented. In order to alleviate chattering, a parameterized tangent hyperbolic has been used as switching function, instead of pure relay one, to the observer and the controller. Also, the gains of the switching functions, to the sliding observer and sliding controller are adaptively updated depending of estimation error and tracking error, respectively. By the using adaptive gains, the transient and tracking response can be improved.

  1. Towards Automatic Controller Design using Multi-Objective Evolutionary Algorithms

    DEFF Research Database (Denmark)

    Pedersen, Gerulf

    of evolutionary computation, a choice was made to use multi-objective algorithms for the purpose of aiding in automatic controller design. More specifically, the choice was made to use the Non-dominated Sorting Genetic Algorithm II (NSGAII), which is one of the most potent algorithms currently in use......, as the foundation for achieving the desired goal. While working with the algorithm, some issues arose which limited the use of the algorithm for unknown problems. These issues included the relative scale of the used fitness functions and the distribution of solutions on the optimal Pareto front. Some work has...

  2. Automatic Scheduling and Planning (ASAP) in future ground control systems

    Science.gov (United States)

    Matlin, Sam

    1988-01-01

    This report describes two complementary approaches to the problem of space mission planning and scheduling. The first is an Expert System or Knowledge-Based System for automatically resolving most of the activity conflicts in a candidate plan. The second is an Interactive Graphics Decision Aid to assist the operator in manually resolving the residual conflicts which are beyond the scope of the Expert System. The two system designs are consistent with future ground control station activity requirements, support activity timing constraints, resource limits and activity priority guidelines.

  3. AUTOMATIC CONTROL OF INTELLECTUAL RIGHTS IN THE GLOBAL COMPUTER NETWORKS

    Directory of Open Access Journals (Sweden)

    Anatoly P. Yakimaho

    2013-01-01

    Full Text Available The problems of use of subjects of intellectual property in the global computer networks are stated. The main attention is focused on the ways of problems solutions arising during the work in computer networks. Legal problems of information society are considered. The analysis of global computer networks as places for the organization of collective management by copyrights in the world scale is carried out. Issues of creation of a system of automatic control of property rights of authors and owners in the global computer networks are taken up.

  4. Consistently Trained Artificial Neural Network for Automatic Ship Berthing Control

    Directory of Open Access Journals (Sweden)

    Y.A. Ahmed

    2015-09-01

    Full Text Available In this paper, consistently trained Artificial Neural Network controller for automatic ship berthing is discussed. Minimum time course changing manoeuvre is utilised to ensure such consistency and a new concept named ‘virtual window’ is introduced. Such consistent teaching data are then used to train two separate multi-layered feed forward neural networks for command rudder and propeller revolution output. After proper training, several known and unknown conditions are tested to judge the effectiveness of the proposed controller using Monte Carlo simulations. After getting acceptable percentages of success, the trained networks are implemented for the free running experiment system to judge the network’s real time response for Esso Osaka 3-m model ship. The network’s behaviour during such experiments is also investigated for possible effect of initial conditions as well as wind disturbances. Moreover, since the final goal point of the proposed controller is set at some distance from the actual pier to ensure safety, therefore a study on automatic tug assistance is also discussed for the final alignment of the ship with actual pier.

  5. Gain Scheduling Control of Gas Turbine Engines: Absolute Stability by Finding a Common Lyapunov Matrix

    OpenAIRE

    Pakmehr, Mehrdad; Fitzgerald, Nathan; Feron, Eric; Shamma, Jeff; Behbahani, Alireza

    2012-01-01

    This manuscript aims to develop and describe gain scheduling control concept for a gas turbine engine which drives a variable pitch propeller. An architecture for gain-scheduling control is developed that controls the turboshaft engine for large thrust commands in stable fashion with good performance. Fuel ow and propeller pitch angle are the two control inputs of the system. New stability proof has been developed for gain scheduling control of gas turbine engines using global linearization a...

  6. Gain-Scheduled Control of a Fossil-Fired Power Plant Boiler

    DEFF Research Database (Denmark)

    Hangstrup, M.; Stoustrup, Jakob; Andersen, Palle;

    1999-01-01

    In this paper the objective is to optimize the control of a coal fired 250 MW power plant boiler. The conventional control system is supplemented with a multivariable optimizing controller operating in parallel with the conventional control system. Due to the strong dependence of the gains...... and dynamics upon the load, it is beneficial to consider a gain-scheduling control approach. Optimization using complex mu synthesis results in unstable LTI controllers in some operating points of the boiler. A recent gain-scheduling approach allowing for unstable fixed LTI controllers is applied. Gain...

  7. Automatic Voltage Control (AVC) System under Uncertainty from Wind Power

    DEFF Research Database (Denmark)

    Qin, Nan; Abildgaard, Hans; Flynn, Damian

    2016-01-01

    An automatic voltage control (AVC) system maintains the voltage profile of a power system in an acceptable range and minimizes the operational cost by coordinating the regulation of controllable components. Typically, all of the parameters in the optimization problem are assumed to be certain...... and constant in the decision making process. However, for high shares of wind power, uncertainty in the decision process due to wind power variability may result in an infeasible AVC solution. This paper proposes a voltage control approach which considers the voltage uncertainty from wind power productions....... The proposed method improves the performance and the robustness of a scenario based approach by estimating the potential voltage variations due to fluctuating wind power production, and introduces a voltage margin to protect the decision against uncertainty for each scenario. The effectiveness of the proposed...

  8. On-line current feed and computer aided control tactics for automatic balancing head

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In the designed automatic balancing head,a non-contact induction transformer is used to deliver driving energy to solve the problem of current fed and controlling on-line.Computer controlled automatic balancing experiments with phase-magnitude control tactics were performed on a flexible rotor system.Results of the experiments prove that the energy feeding method and the control tactics are effective in the automatic balancing head for vibration controlling.

  9. Adaptive Control for Nonlinear Systems with Time-Varying Control Gain

    Directory of Open Access Journals (Sweden)

    Alejandro Rincon

    2012-01-01

    Full Text Available We propose a scheme for nonlinear plants with time-varying control gain and time-varying plant coefficients, on the basis of a plant model consisting of a Brunovsky-type model with polynomials as approximators. We develop an adaptive robust control scheme for this plant, under the following assumptions: (i the plant terms involve time-varying but bounded coefficients, being its upper bound unknown; (ii the control gain is unknown, not necessarily bounded, and only its signum is known. To achieve robustness, we use a combination of robustifying control inputs and dead zone-type update laws. We apply this methodology to the speed control of a permanent magnet synchronous motor (PMSM, and we achieve proper tracking results.

  10. Automatic Thermal Control System with Temperature Difference or Derivation Feedback

    Directory of Open Access Journals (Sweden)

    Darina Matiskova

    2016-02-01

    Full Text Available Automatic thermal control systems seem to be non-linear systems with thermal inertias and time delay. A controller is also non-linear because its information and power signals are limited. The application of methods that are available to on-linear systems together with computer simulation and mathematical modelling creates a possibility to acquire important information about the researched system. This paper provides a new look at the heated system model and also designs the structure of the thermal system with temperature derivation feedback. The designed system was simulated by using a special software in Turbo Pascal. Time responses of this system are compared to responses of a conventional thermal system. The thermal system with temperature derivation feedback provides better transients, better quality of regulation and better dynamical properties.

  11. Automatic Meter Reading and Theft Control System by Using GSM

    Directory of Open Access Journals (Sweden)

    P. Rakesh Malhotra

    2013-04-01

    Full Text Available This paper deals with automatic meter reading and theft control system in energy meter. Current transformer is used to measure the total power consumption for house or industrial purpose. This recorded reading is transmitted to the electricity board for every 60 days once. For transmitting the reading of energy meter GSM module is used. To avoid theft, infrared sensor is placed in the screw portion of energy meter seal. If the screw is removed from the meter a message is sent to the electricity board. The measuring of energy meter and monitoring of IR sensor is done with a PIC microcontroller.The informative system will be helpful for the electricity board to monitor the entire supply and the correct billing accordingly without any mishap. This model reduces the manual manipulation work andtheft control.

  12. Automatic diagnosis and control of distributed solid state lighting systems.

    Science.gov (United States)

    Dong, Jianfei; van Driel, Willem; Zhang, Guoqi

    2011-03-28

    This paper describes a new design concept of automatically diagnosing and compensating LED degradations in distributed solid state lighting (SSL) systems. A failed LED may significantly reduce the overall illumination level, and destroy the uniform illumination distribution achieved by a nominal system. To our knowledge, an automatic scheme to compensate LED degradations has not yet been seen in the literature, which requires a diagnostic step followed by control reconfigurations. The main challenge in diagnosing LED degradations lies in the usually unsatisfactory observability in a distributed SSL system, because the LED light output is usually not individually measured. In this work, we tackle this difficulty by using pulse width modulated (PWM) drive currents with a unique fundamental frequency assigned to each LED. Signal processing methods are applied in estimating the individual illumination flux of each LED. Statistical tests are developed to diagnose the degradation of LEDs. Duty cycle of the drive current signal to each LED is re-optimized once a fault is detected, in order to compensate the destruction of the uniform illumination pattern by the failed LED.

  13. OPTIMAL CONTROL APPLIED IN AUTOMATIC CLUTCH ENGAGEMENTS OF VEHICLES

    Institute of Scientific and Technical Information of China (English)

    Sun Chengshun; Zhang Jianwu

    2004-01-01

    Start-up working condition is the key to the research of optimal engagement of automatic clutch for AMT.In order to guarantee an ideal dynamic performance of the clutch engagement,an optimal controller is designed by considering throttle angle,engine speed,gear ratio,vehicle acceleration and road condition.The minimum value principle is also introduced to achieve an optimal dynamic performance of the nonlinear system compromised in friction plate wear and vehicle drive quality.The optimal trajectory of the clutch engagement can be described in the form of explicit and analytical expressions and characterized by the deterministic and accurate control strategy in stead of indeterministic and soft control techniques which need thousands of experiments.For validation of the controller,test work is carried out for the automated clutch engagements in a commercial car with an traditional mechanical transmission,a hydraulic actuator,a group of sensors and a portable computer system.It is shown through experiments that dynamic behaviors of the clutch engagement operated by the optimal control are more effective and efficient than those by fuzzy control.

  14. Knowledge-based system for automatic MBR control.

    Science.gov (United States)

    Comas, J; Meabe, E; Sancho, L; Ferrero, G; Sipma, J; Monclús, H; Rodriguez-Roda, I

    2010-01-01

    MBR technology is currently challenging traditional wastewater treatment systems and is increasingly selected for WWTP upgrading. MBR systems typically are constructed on a smaller footprint, and provide superior treated water quality. However, the main drawback of MBR technology is that the permeability of membranes declines during filtration due to membrane fouling, which for a large part causes the high aeration requirements of an MBR to counteract this fouling phenomenon. Due to the complex and still unknown mechanisms of membrane fouling it is neither possible to describe clearly its development by means of a deterministic model, nor to control it with a purely mathematical law. Consequently the majority of MBR applications are controlled in an "open-loop" way i.e. with predefined and fixed air scour and filtration/relaxation or backwashing cycles, and scheduled inline or offline chemical cleaning as a preventive measure, without taking into account the real needs of membrane cleaning based on its filtration performance. However, existing theoretical and empirical knowledge about potential cause-effect relations between a number of factors (influent characteristics, biomass characteristics and operational conditions) and MBR operation can be used to build a knowledge-based decision support system (KB-DSS) for the automatic control of MBRs. This KB-DSS contains a knowledge-based control module, which, based on real time comparison of the current permeability trend with "reference trends", aims at optimizing the operation and energy costs and decreasing fouling rates. In practice the automatic control system proposed regulates the set points of the key operational variables controlled in MBR systems (permeate flux, relaxation and backwash times, backwash flows and times, aeration flow rates, chemical cleaning frequency, waste sludge flow rate and recycle flow rates) and identifies its optimal value. This paper describes the concepts and the 3-level architecture

  15. Human interface, automatic planning, and control of a humanoid robot

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Y.K. [Korea Inst. of Science and Technology, Seoul (Korea, Republic of)]|[Sandia National Labs., Albuquerque, NM (United States); Kang, S.C.; Lee, S.; Cho, K.R.; Kim, H.S.; Lee, C.W. [Korea Inst. of Science and Technology, Seoul (Korea, Republic of); Park, S.M. [Jeonju Technical Coll. (Korea, Republic of)

    1998-11-01

    This paper presents an integrated robotic system consisting of human interfaces, motion- and grasp-planning algorithms, a controller, a graphical simulator, and a humanoid robot with over 60 joints. All of these subsystems are integrated in a coordinated fashion to enable the robot to perform a commanded task with as much autonomy as possible. The highest level of the system is the human interfaces, which enable a user to specify tasks conveniently and efficiently. At the mid-level, several planning algorithms generate motions of the robot body, arms, and hands automatically. At the lowest level, the motor controllers are equipped with both a position controller and a compliant motion controller to execute gross motions and contact motions, respectively. The main contributions of the work are the large-scale integration and the development of the motion planners for a humanoid robot. A hierarchical integration scheme that preserves the modularities of the human interfaces, the motion planners, and the controller has been the key for the successful integration. The set of motion planners is developed systematically so as to coordinate the motions of the body, arms, and hands to perform a large variety of tasks.

  16. Control of microbial fuel cell voltage using a gain scheduling control strategy

    Science.gov (United States)

    Boghani, Hitesh C.; Michie, Iain; Dinsdale, Richard M.; Guwy, Alan J.; Premier, Giuliano C.

    2016-08-01

    Recent microbial fuel cell (MFC) research frequently addresses matters associated with scale and deployability. Modularisation is often needed to reduce ohmic losses with increasing volume. Series/parallel is then often an obvious strategy to enhance power quality during operation, to make best use of generated electricity. Hence, voltage reversal resulting from power and voltage mismatch between cells become virtually unavoidable. Control MFC voltages could be used to stabilise MFC stacks. Here, nonlinear MFCs are controlled using simple gain scheduled Proportional + Integral actions. Parsimonious control may be necessary for implementation in MFC arrays, so minimising costs. Controller parameterisation used several linearised models over the dynamic operating range of the MFCs. Controller gains were then scheduled according to the operating conditions. A digital potentiometer was used to actuate the control, varying the current sourced from the MFC. The results show that the controller was able to control MFC voltages, rejecting the disturbances. It was shown that the controller was transferable between MFCs with different power performances. This study demonstrates that the control of MFCs can be achieved with relatively simple digital approaches, plausibly implementable using low cost microcontrollers, and likely to be useful in the effective deployment of MFCs in large scale arrays.

  17. Multi-dimensional Gain Scheduling with Application to Power Plant Control

    DEFF Research Database (Denmark)

    Bendtsen, Jan Dimon; Stoustrup, Jakob; Trangbæk, Klaus

    2003-01-01

    This paper deals with gain scheduling control of a power plant model, which is an example of a multi-dimensional nonlinear system. Linear observer-based controllers are designed for a number of linear approximations of the system model in a set of operating points, and gain-scheduling control can...

  18. From the Conception to the Marketing of a New Automatic Control

    DEFF Research Database (Denmark)

    Nielsen, Peter V.; Kildegaard, Erik; Boel, Jan

    1985-01-01

    From a historical viewpoint, product technology has developed via radiator thermostats, return thermostats and selfacting automatic temperature and pressure controls towards more integrated automatic control systems also including weather compensators, which offer benefits in the form of energy...... savings and improved comfort. As a continuation of this development, Danfoss has this year introduced a new electronic automatic control system, the RPS 2000, which deserves closer scrutiny....

  19. Research on key control technologies of all-position automatic welding machine

    Institute of Scientific and Technical Information of China (English)

    Zeng Huilin; Du Zeyu; Ma Jing; Huang Fuxiang

    2009-01-01

    The pipeline all-position automatic welding machine system is a special welding system for automatically welding circumferential joint of pipeline on site, which has been widely used to the long-distance pipeline construction projects due to the advantages of automatic control for welding parameters at all-position, moving speed of bugs and operating. In this paper, the key control technologies of PAWM all-position automatic welding machine (developed by Pipeline Research Institute of CNPC) such as the automatic control system, control software, personal digital assistant (PDA) software and complex programmable logic device(CPLD) program as well as the control method of welding parameter have been described detailedly. With the higher welding quality, higher welding efficiency and lower labor intensity, PAWM all-position automatic welding machine has been successfully applied in many famous pipeline construction projects.

  20. Effectiveness of Automatic Control over Flash Distillation Kettle for Liquid-Phase Bulk Polymerization of Propylene

    Institute of Scientific and Technical Information of China (English)

    Han Linge; Ma Jiantong

    2004-01-01

    Automatic control over flash distillation section at SINOPEC Cangzhou Refinery has been realized, resulting in saving of propylene feedstock and emission reduction to harvest significant economic benefits.

  1. Backstepping Designs for Aircraft Control - What is there to Gain?

    OpenAIRE

    Härkegård, Ola

    2001-01-01

    Aircraft flight control design is traditionally based on linear control theory, due to the existing wealth of tools for linear design and analysis. However, in order to achieve tactical advantages, modern fighter aircraft strive towards performing maneuvers outside the region where the dynamics of flight are linear, and the need for nonlinear tools arises. In this paper, backstepping is proposed as a possible framework for nonlinear flight control design. Its capabilities of handling five maj...

  2. Indonesian Automatic Speech Recognition For Command Speech Controller Multimedia Player

    Directory of Open Access Journals (Sweden)

    Vivien Arief Wardhany

    2014-12-01

    Full Text Available The purpose of multimedia devices development is controlling through voice. Nowdays voice that can be recognized only in English. To overcome the issue, then recognition using Indonesian language model and accousticc model and dictionary. Automatic Speech Recognizier is build using engine CMU Sphinx with modified english language to Indonesian Language database and XBMC used as the multimedia player. The experiment is using 10 volunteers testing items based on 7 commands. The volunteers is classifiedd by the genders, 5 Male & 5 female. 10 samples is taken in each command, continue with each volunteer perform 10 testing command. Each volunteer also have to try all 7 command that already provided. Based on percentage clarification table, the word “Kanan” had the most recognize with percentage 83% while “pilih” is the lowest one. The word which had the most wrong clarification is “kembali” with percentagee 67%, while the word “kanan” is the lowest one. From the result of Recognition Rate by male there are several command such as “Kembali”, “Utama”, “Atas “ and “Bawah” has the low Recognition Rate. Especially for “kembali” cannot be recognized as the command in the female voices but in male voice that command has 4% of RR this is because the command doesn’t have similar word in english near to “kembali” so the system unrecognize the command. Also for the command “Pilih” using the female voice has 80% of RR but for the male voice has only 4% of RR. This problem is mostly because of the different voice characteristic between adult male and female which male has lower voice frequencies (from 85 to 180 Hz than woman (165 to 255 Hz.The result of the experiment showed that each man had different number of recognition rate caused by the difference tone, pronunciation, and speed of speech. For further work needs to be done in order to improving the accouracy of the Indonesian Automatic Speech Recognition system

  3. Automatic Tuning of PID Controller for a 1-D Levitation System Using a Genetic Algorithm

    DEFF Research Database (Denmark)

    Yang, Zhenyu; Pedersen, Gerulf K.m.

    2006-01-01

    The automatic PID control design for a onedimensional magnetic levitation system is investigated. The PID controller is automatically tuned using the non-dominated sorting genetic algorithm (NSGA-II) based on a nonlinear system model. The developed controller is digitally implemented and tested...

  4. 14 CFR Appendix I to Part 25 - Installation of an Automatic Takeoff Thrust Control System (ATTCS)

    Science.gov (United States)

    2010-01-01

    ... Appendix I to Part 25—Installation of an Automatic Takeoff Thrust Control System (ATTCS) I25.1General. (a... crew to increase thrust or power. I25.2Definitions. (a) Automatic Takeoff Thrust Control System (ATTCS... Control System (ATTCS) I Appendix I to Part 25 Aeronautics and Space FEDERAL AVIATION...

  5. Differential evolution algorithm based automatic generation control for interconnected power systems with

    Directory of Open Access Journals (Sweden)

    Banaja Mohanty

    2014-09-01

    Full Text Available This paper presents the design and performance analysis of Differential Evolution (DE algorithm based Proportional–Integral (PI and Proportional–Integral–Derivative (PID controllers for Automatic Generation Control (AGC of an interconnected power system. Initially, a two area thermal system with governor dead-band nonlinearity is considered for the design and analysis purpose. In the proposed approach, the design problem is formulated as an optimization problem control and DE is employed to search for optimal controller parameters. Three different objective functions are used for the design purpose. The superiority of the proposed approach has been shown by comparing the results with a recently published Craziness based Particle Swarm Optimization (CPSO technique for the same interconnected power system. It is noticed that, the dynamic performance of DE optimized PI controller is better than CPSO optimized PI controllers. Additionally, controller parameters are tuned at different loading conditions so that an adaptive gain scheduling control strategy can be employed. The study is further extended to a more realistic network of two-area six unit system with different power generating units such as thermal, hydro, wind and diesel generating units considering boiler dynamics for thermal plants, Generation Rate Constraint (GRC and Governor Dead Band (GDB non-linearity.

  6. Two stage dual gate MESFET monolithic gain control amplifier for Ka-band

    Science.gov (United States)

    Sokolov, V.; Geddes, J.; Contolatis, A.

    A monolithic two stage gain control amplifier has been developed using submicron gate length dual gate MESFETs fabricated on ion implanted material. The amplifier has a gain of 12 dB at 30 GHz with a gain control range of over 30 dB. This ion implanted monolithic IC is readily integrable with other phased array receiver functions such as low noise amplifiers and phase shifters.

  7. Development and Operation of an Automatic Rotor Trim Control System for the UH-60 Individual Blade Control Wind Tunnel Test

    Science.gov (United States)

    Theodore, Colin R.; Tischler, Mark B.

    2010-01-01

    An automatic rotor trim control system was developed and successfully used during a wind tunnel test of a full-scale UH-60 rotor system with Individual Blade Control (IBC) actuators. The trim control system allowed rotor trim to be set more quickly, precisely and repeatably than in previous wind tunnel tests. This control system also allowed the rotor trim state to be maintained during transients and drift in wind tunnel flow, and through changes in IBC actuation. The ability to maintain a consistent rotor trim state was key to quickly and accurately evaluating the effect of IBC on rotor performance, vibration, noise and loads. This paper presents details of the design and implementation of the trim control system including the rotor system hardware, trim control requirements, and trim control hardware and software implementation. Results are presented showing the effect of IBC on rotor trim and dynamic response, a validation of the rotor dynamic simulation used to calculate the initial control gains and tuning of the control system, and the overall performance of the trim control system during the wind tunnel test.

  8. OPTIMAL-TUNING OF PID CONTROLLER GAINS USING GENETIC ALGORITHMS

    Directory of Open Access Journals (Sweden)

    Ömer GÜNDOĞDU

    2005-01-01

    Full Text Available This paper presents a method of optimum parameter tuning of a PID controller to be used in driving an inertial load by a dc motor thorough a gearbox. Specifically, the method uses genetic algorithms to determine the optimum controller parameters by minimizing the sum of the integral of the squared error and the squared controller output deviated from its steady state value. The paper suggests the use of Ziegler-Nichols settings to form the intervals for the controller parameters in which the population to be formed. The results obtained from the genetic algorithms are compared with the ones from Ziegler-Nichols in both figures and tabular form. Comparatively better results are obtained in the genetic algorithm case.

  9. Application of Feedback Linearization Method in Airplane Automatic Landing Control System

    Institute of Scientific and Technical Information of China (English)

    Wang Xiaoyan; Feng Jiang; Feng Xiujuan; Wu Junqin

    2004-01-01

    Summarizes the I/O feedback linearization about MIMO system, and applies it to nonlinear control equation of airplane. And also designs the tracing control laws for airplane longitudinal automatic landing control system.

  10. Pressure-control purge panel for automatic butt welding

    Science.gov (United States)

    Lang, E. J.; Van Wagner, B. H.

    1969-01-01

    Modification of a purge panel for use in an automatic butt weld reduces the drop in pressure between the regulators and the weld head and tube purge fitting. The invention affects air regulators for plants, regulating circuits for pneumatic valves, and automatic welding machines.

  11. Research in Adaptronic Automatic Control System and Biosensor System Modelling

    Directory of Open Access Journals (Sweden)

    Skopis Vladimir

    2015-07-01

    Full Text Available This paper describes the research on adaptronic systems made by the author and offers to use biosensors that can be later inserted into the adaptronic systems. Adaptronic systems are based, on the one hand, on the adaptronic approach when the system is designed not to always meet the worst condition, but to change the structure of the system according to the external conditions. On the other hand, it is an extension of common automatic control ad adaptive systems. So, in the introduction firstly the adaptronic approach and biosensor as a term is explained. Adaptive systems, upon which adaptronic ones are based, are also mentioned. Then the construction of biosensor is described, as well as some information is given about the classification of biosensors and their main groups. Also it is suggested to use lichen indicators in industry to control concentration of chemical substances in the air. After that mathematical models and computer experiments for adaptronic system and biosensor analysis are given.

  12. Vector Control Algorithm for Electric Vehicle AC Induction Motor Based on Improved Variable Gain PID Controller

    Directory of Open Access Journals (Sweden)

    Gang Qin

    2015-01-01

    Full Text Available The acceleration performance of EV, which affects a lot of performances of EV such as start-up, overtaking, driving safety, and ride comfort, has become increasingly popular in recent researches. An improved variable gain PID control algorithm to improve the acceleration performance is proposed in this paper. The results of simulation with Matlab/Simulink demonstrate the effectiveness of the proposed algorithm through the control performance of motor velocity, motor torque, and three-phase current of motor. Moreover, it is investigated that the proposed controller is valid by comparison with the other PID controllers. Furthermore, the AC induction motor experiment set is constructed to verify the effect of proposed controller.

  13. Bidders' gains and family control of private target firms

    NARCIS (Netherlands)

    Gonenc, Halit; Hermes, Niels; van Sinderen, Erik

    2013-01-01

    This paper examines the announcement returns of bidders acquiring private firms owned by families versus the returns of bidders acquiring non-family controlled private firms. The sample consists of 391 acquisitions of private targets in seven continental European countries for the period 1997-2008.

  14. 3D position measurement using square marker for automatic mobile robot control

    Science.gov (United States)

    Sakamoto, Kunio; Ohmori, Koji

    2010-11-01

    A mobile robot is an automatic machine that is capable of movement in a given environment. Many techniques of automatic control are proposed. A line tracer is one of the most popular robots. The line tracer goes along a white line on the floor. The authors developed a mobile robot which moves to indicated point automatically. All you have to do is to indicate a goal point. In this paper, we propose an automatic mobile robot system controlled by an invisible marker and remote indication using the augmented reality technology.

  15. A High Efficiency Variable Gain Amplifier Circuit with Controllable Transconductance Amp

    Science.gov (United States)

    Okura, Tetsuro; Okura, Shunsuke; Ido, Toru; Taniguchi, Kenji

    A novel power reduction technique for a variable gain amplifier (VGA) with a two-stage operational amplifier is proposed. The technique improves the power consumption of a VGA by optimizing the bandwidth and the phase margin dynamically on all gain range of the VGA through controlling the input transconductance of opamp. A VGA utilizing the proposed technique shows 40% reduction of power consumption against a conventional VGA at the best condition of VGA gain range.

  16. Automatic brain matter segmentation of computed tomography images using a statistical model: A tool to gain working time!

    Science.gov (United States)

    Bertè, Francesco; Lamponi, Giuseppe; Bramanti, Placido; Calabrò, Rocco S

    2015-10-01

    Brain computed tomography (CT) is useful diagnostic tool for the evaluation of several neurological disorders due to its accuracy, reliability, safety and wide availability. In this field, a potentially interesting research topic is the automatic segmentation and recognition of medical regions of interest (ROIs). Herein, we propose a novel automated method, based on the use of the active appearance model (AAM) for the segmentation of brain matter in CT images to assist radiologists in the evaluation of the images. The method described, that was applied to 54 CT images coming from a sample of outpatients affected by cognitive impairment, enabled us to obtain the generation of a model overlapping with the original image with quite good precision. Since CT neuroimaging is in widespread use for detecting neurological disease, including neurodegenerative conditions, the development of automated tools enabling technicians and physicians to reduce working time and reach a more accurate diagnosis is needed.

  17. Automatic channel trimming for control systems: A concept

    Science.gov (United States)

    Vandervoort, R. J.; Sykes, H. A.

    1977-01-01

    Set of bias signals added to channel inputs automatically normalize differences between channels. Algorithm and second feedback loop compute trim biases. Concept could be applied to regulators and multichannel servosystems for remote manipulators in undersea mining.

  18. Dynamic Optimization of Feedforward Automatic Gauge Control Based on Extended Kalman Filter

    Institute of Scientific and Technical Information of China (English)

    YANG Bin-hu; YANG Wei-dong; CHEN Lian-gui; QU Lei

    2008-01-01

    Automatic gauge control is an essentially nonlinear process varying with time delay, and stochastically varying input and process noise always influence the target gauge control accuracy. To improve the control capability of feedforward automatic gauge control, Kalman filter was employed to filter the noise signal transferred from one stand to another. The linearized matrix that the Kalman filter algorithm needed was concluded; thus, the feedforward automatic gauge control architecture was dynamically optimized. The theoretical analyses and simulation show that the proposed algorithm is reasonable and effective.

  19. Switched-Observer-Based Adaptive Neural Control of MIMO Switched Nonlinear Systems With Unknown Control Gains.

    Science.gov (United States)

    Long, Lijun; Zhao, Jun

    2016-05-02

    In this paper, the problem of adaptive neural output-feedback control is addressed for a class of multi-input multioutput (MIMO) switched uncertain nonlinear systems with unknown control gains. Neural networks (NNs) are used to approximate unknown nonlinear functions. In order to avoid the conservativeness caused by adoption of a common observer for all subsystems, an MIMO NN switched observer is designed to estimate unmeasurable states. A new switched observer-based adaptive neural control technique for the problem studied is then provided by exploiting the classical average dwell time (ADT) method and the backstepping method and the Nussbaum gain technique. It effectively handles the obstacle about the coexistence of multiple Nussbaum-type function terms, and improves the classical ADT method, since the exponential decline property of Lyapunov functions for individual subsystems is no longer satisfied. It is shown that the technique proposed is able to guarantee semiglobal uniformly ultimately boundedness of all the signals in the closed-loop system under a class of switching signals with ADT, and the tracking errors converge to a small neighborhood of the origin. The effectiveness of the approach proposed is illustrated by its application to a two inverted pendulum system.

  20. A low-power high-performance configurable auto-gain control loop for a digital hearing aid SoC

    Science.gov (United States)

    Chengying, Chen; Hainan, Liu; Yong, Hei; Jun, Fan; Xiaoyu, Hu

    2013-10-01

    A low-power, configurable auto-gain control loop for a digital hearing aid system on a chip (SoC) is presented. By adopting a mixed-signal feedback control structure and peak detection and judgment, it can work in automatic gain or variable gain control modes through a digital signal processing unit. A noise-reduction and dynamic range (DR) improvement technique is also used to ensure the DR of the circuit in a low-voltage supply. The circuit is implemented in an SMIC 0.13 μm 1P8M CMOS process. The measurement results show that in a 1 V power supply, 1.6 kHz input frequency and 200 mVp—p, the SFDR is 74.3 dB, the THD is 66.1 dB, and the total power is 89 μW, meeting the application requirements of hearing aid SoCs.

  1. Devises of automatic for controling of microwave stove for food products’ incinerating

    Directory of Open Access Journals (Sweden)

    M. O. Gren

    2008-05-01

    Full Text Available Development of automatic meant for controlling of microwave oven with the possibility of work on the base of few magnetrons and controlling temperature at the same time with VSWR are represented.

  2. Comparison of gradient methods for gain tuning of a PD controller applied on a quadrotor system

    Science.gov (United States)

    Kim, Jinho; Wilkerson, Stephen A.; Gadsden, S. Andrew

    2016-05-01

    Many mechanical and electrical systems have utilized the proportional-integral-derivative (PID) control strategy. The concept of PID control is a classical approach but it is easy to implement and yields a very good tracking performance. Unmanned aerial vehicles (UAVs) are currently experiencing a significant growth in popularity. Due to the advantages of PID controllers, UAVs are implementing PID controllers for improved stability and performance. An important consideration for the system is the selection of PID gain values in order to achieve a safe flight and successful mission. There are a number of different algorithms that can be used for real-time tuning of gains. This paper presents two algorithms for gain tuning, and are based on the method of steepest descent and Newton's minimization of an objective function. This paper compares the results of applying these two gain tuning algorithms in conjunction with a PD controller on a quadrotor system.

  3. An application of gain-scheduled control using state-space interpolation to hydroactive gas bearings

    DEFF Research Database (Denmark)

    Theisen, Lukas Roy Svane; Camino, Juan F.; Niemann, Hans Henrik

    2016-01-01

    , it is possible to design a gain-scheduled controller using multiple controllers optimised for a single frequency. Gain-scheduling strategies using the Youla parametrisation can guarantee stability at the cost of increased controller order and performance loss in the interpolation region. This paper contributes...... with a gain-scheduling strategy using state-space interpolation, which avoids both the performance loss and the increase of controller order associated to the Youla parametrisation. The proposed state-space interpolation for gain-scheduling is applied for mass imbalance rejection for a controllable gas...... bearing scheduled in two parameters. Comparisons against the Youla-based scheduling demonstrate the superiority of the state-space interpolation....

  4. Second order sliding control with state dependent gain and its application to a hydraulic drive

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Andersen, Torben Ole; Pedersen, Henrik C.

    2013-01-01

    for improved convergence speed, and the gain of the discontinuous control is made variable according to the control target itself. It is shown that the control error and its derivative are globally convergent to a vicinity of the target via Lyapunov arguments, with accuracy dependent on control parameters...

  5. Fuzzy logic control strategy for submerged arc automatic welding of digital controlling

    Institute of Scientific and Technical Information of China (English)

    He Kuanfang; Huang Shisheng; Zhou Yiqing; Wang Zhenmin

    2008-01-01

    A microcomputer control system based on 80C320 and a switching regulation of wire feeder were designed. A correction factor based double model fuzzy logic controller (FLC) was introduced to achieve welding digital and intellectualized control by means of wire feeding speed feedback. The controller has many functions such as keyboard input, light emitting diode (LED) display and real-time intellectualized control of welding process etc. The controlling performance influenced by the coefficient of correction function was discussed. It was concluded by the experiments the relation between the coefftcient of correction function and welding quality, when the coefficient of correction function is great, the dynamic character of controller is better, when the coefficient of correction function is small, the sensitivity character of controller is better. Experimental results also show that digital and fuzzy logic control method enable the improvement of appearance of weld and stability of welding process to be achieved in submerged arc automatic welding.

  6. Floquet control of the gain and loss in a PT-symmetric optical coupler

    Science.gov (United States)

    Wu, Yi; Zhu, Bo; Hu, Shu-Fang; Zhou, Zheng; Zhong, Hong-Hua

    2017-02-01

    Controlling the balanced gain and loss in a PT-symmetric system is a rather challenging task. Utilizing Floquet theory, we explore the constructive role of periodic modulation in controlling the gain and loss of a PT-symmetric optical coupler. It is found that the gain and loss of the system can be manipulated by applying a periodic modulation. Further, such an original non-Hermitian system can even be modulated into an effective Hermitian system derived by the high-frequency Floquet method. Therefore, compared with other PT symmetry control schemes, our protocol can modulate the unbroken PT-symmetric range to a wider parameter region. Our results provide a promising approach for controlling the gain and loss of a realistic system.

  7. 46 CFR 61.30-20 - Automatic control and safety tests.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Automatic control and safety tests. 61.30-20 Section 61.30-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PERIODIC TESTS AND INSPECTIONS Tests and Inspections of Fired Thermal Fluid Heaters § 61.30-20 Automatic...

  8. Effect of Weight Gain on Cardiac Autonomic Control During Wakefulness and Sleep

    Science.gov (United States)

    Adachi, Taro; Sert-Kuniyoshi, Fatima H.; Calvin, Andrew D.; Singh, Prachi; Romero-Corral, Abel; van der Walt, Christelle; Davison, Diane E.; Bukartyk, Jan; Konecny, Tomas; Pusalavidyasagar, Snigdha; Sierra-Johnson, Justo; Somers, Virend K.

    2012-01-01

    Obesity has been associated with increased cardiac sympathetic activation during wakefulness, but the effect on sleep-related sympathetic modulation is not known. The aim of this study was to investigate the effect of fat gain on cardiac autonomic control during wakefulness and sleep in humans. We performed a randomized controlled study to assess the effects of fat gain on heart rate variability (HRV). We recruited 36 healthy volunteers, who were randomized to either a standardized diet to gain approximately 4 kg over 8 weeks followed by an 8 week weight loss period (n=20), or to serve as a weight-maintainer control (n=16). An overnight polysomnogram with power spectral analysis of HRV was performed at baseline, after weight gain, and after weight loss to determine the ratio of low frequency (LF) to high frequency (HF) power, and to examine the relationship between changes in HRV and changes in insulin, leptin and adiponectin levels. Mean weight gain was 3.9 kg in the fat gain group versus 0.1 kg in the maintainer group. LF/HF increased both during wakefulness and sleep after fat gain and returned to baseline after fat loss in the fat gain group, and did not change in the control group. Insulin, leptin and adiponectin also increased after fat gain and fell after fat loss, but no clear pattern of changes were seen that correlated consistently with changes in HRV. Short-term fat gain in healthy subjects is associated with increased cardiac sympathetic activation during wakefulness and sleep but the mechanisms remain unclear. PMID:21357280

  9. Raman-based distributed temperature sensor using simplex code and gain controlled EDFA

    Science.gov (United States)

    Bassan, F. R.; Penze, R. S.; Leonardi, A. A.; Fracarolli, J. P. V.; Floridia, C.; Rosolem, J. B.; Fruett, F.

    2015-09-01

    In this work we present a comparison between simplex coded and optical amplified simplex coded Raman based Distributed Temperature Sensing (DTS). An increase in performance is demonstrated using erbium doped fiber amplifier (EDFA) with proper gain control scheme that allows a DTS operates with simplex code. Using 63-bit simplex code and gain controlled EDFA we demonstrated the temperature resolution and dynamic range improvement in 16 °C @ 10 km and 4 dB, respectively.

  10. Analysis of automobile’s automatic control systems for the hill climbing start

    Directory of Open Access Journals (Sweden)

    Valeriy I. Klimenko

    2014-12-01

    Full Text Available To improve road safety while driving on the rise, facilitating the driver’s activity the automobile industry leaders are introducing automatic hill-hold control systems into the car design. This study purpose relates to the existing automatic start control systems’ design analysis. Analyzed are the existing design developments of automatic hill start assist control systems applied for driving at the start of the climbing. The effected research allows to select the scheme for further development of start driving automatic control systems. Further improvement of driving control systems and primarily the driver assistance hill-hold control systems is necessary to increase both the driving comfort and the traffic safety.

  11. Terminal area automatic navigation, guidance and control research using the Microwave Landing System (MLS). Part 5: Design and development of a Digital Integrated Automatic Landing System (DIALS) for steep final approach using modern control techniques

    Science.gov (United States)

    Halyo, N.

    1983-01-01

    The design and development of a 3-D Digital Integrated Automatic Landing System (DIALS) for the Terminal Configured Vehicle (TCV) Research Aircraft, a B-737-100 is described. The system was designed using sampled data Linear Quadratic Gaussian (LOG) methods, resulting in a direct digital design with a modern control structure which consists of a Kalman filter followed by a control gain matrix, all operating at 10 Hz. DIALS uses Microwave Landing System (MLS) position, body-mounted accelerometers, as well as on-board sensors usually available on commercial aircraft, but does not use inertial platforms. The phases of the final approach considered are the localizer and glideslope capture which may be performed simultaneously, localizer and steep glideslope track or hold, crab/decrab and flare to touchdown. DIALS captures, tracks and flares from steep glideslopes ranging from 2.5 deg to 5.5 deg, selected prior to glideslope capture. Digital Integrated Automatic Landing System is the first modern control design automatic landing system successfully flight tested. The results of an initial nonlinear simulation are presented here.

  12. A Uniform Voltage Gain Control for Alignment Robustness in Wireless EV Charging

    Directory of Open Access Journals (Sweden)

    Yabiao Gao

    2015-08-01

    Full Text Available The efficiency of wireless power transfer is sensitive to the horizontal and vertical distances between the transmitter and receiver coils due to the magnetic coupling change. To address the output voltage variation and efficiency drop caused by misalignment, a uniform voltage gain frequency control is implemented to improve the power delivery and efficiency of wireless power transfer under misalignment. The frequency is tuned according to the amplitude and phase-frequency characteristics of coupling variations in order to maintain a uniform output voltage in the receiver coil. Experimental comparison of three control methods, including fixed frequency control, resonant frequency control, and the proposed uniform gain control was conducted and demonstrated that the uniform voltage gain control is the most robust method for managing misalignment in wireless charging applications.

  13. Gain-Scheduled Model Predictive Control of Wind Turbines using Laguerre Functions

    DEFF Research Database (Denmark)

    Adegas, Fabiano Daher; Wisniewski, Rafal; Larsen, Lars Finn Sloth

    2014-01-01

    This paper presents a systematic approach to design gain-scheduled predictive controllers for wind turbines. The predictive control law is based on Laguerre functions to parameterize control signals and a parameter-dependent cost function that is analytically determined from turbine data. These p...

  14. Small-Scale Helicopter Automatic Autorotation: Modeling, Guidance, and Control

    NARCIS (Netherlands)

    Taamallah, S.

    2015-01-01

    Our research objective consists in developing a, model-based, automatic safety recovery system, for a small-scale helicopter Unmanned Aerial Vehicle (UAV) in autorotation, i.e. an engine OFF flight condition, that safely flies and lands the helicopter to a pre-specified ground location. In pursuit o

  15. Adaptation as a mechanism for gain control in cockroach ON and OFF olfactory receptor neurons.

    Science.gov (United States)

    Burgstaller, Maria; Tichy, Harald

    2012-02-01

    In many sensory systems adaptation acts as a gain control mechanism that optimizes sensory performance by trading increased sensitivity to low stimulus intensity for decreased sensitivity to high stimulus intensity. Adaptation of insect antennal olfactory receptor neurons (ORNs) has been studied for strong odour concentrations, either pulsed or constant. Here, we report that during slowly oscillating changes in the concentration of the odour of lemon oil, the ON and OFF ORNs on the antenna of the cockroach Periplaneta americana adapt to the actual odour concentration and the rate at which concentration changes. When odour concentration oscillates rapidly with brief periods, adaptation improves gain for instantaneous odour concentration and reduces gain for the rate of concentration change. Conversely, when odour concentration oscillates slowly with long periods, adaptation increases gain for the rate of change at the expense of instantaneous concentration. Without this gain control the ON and OFF ORNs would, at brief oscillation periods, soon reach their saturation level and become insensitive to further concentration increments and decrements. At long oscillation periods, on the other hand, the cue would simply be that the discharge begins to change. Because of the high gain for the rate of change, the cockroach will receive creeping changes in odour concentration, even if they persist in one direction. Gain control permits a high degree of precision at small rates when it counts most, without sacrificing the range of detection and without extending the measuring scale.

  16. Path Tracking Control of Automatic Parking Cloud Model considering the Influence of Time Delay

    Directory of Open Access Journals (Sweden)

    Yiding Hua

    2017-01-01

    Full Text Available This paper establishes the kinematic model of the automatic parking system and analyzes the kinematic constraints of the vehicle. Furthermore, it solves the problem where the traditional automatic parking system model fails to take into account the time delay. Firstly, based on simulating calculation, the influence of time delay on the dynamic trajectory of a vehicle in the automatic parking system is analyzed under the transverse distance Dlateral between different target spaces. Secondly, on the basis of cloud model, this paper utilizes the tracking control of an intelligent path closer to human intelligent behavior to further study the Cloud Generator-based parking path tracking control method and construct a vehicle path tracking control model. Moreover, tracking and steering control effects of the model are verified through simulation analysis. Finally, the effectiveness and timeliness of automatic parking controller in the aspect of path tracking are tested through a real vehicle experiment.

  17. Freezing of gait in Parkinson’s disease: disturbances in automaticity and control

    Directory of Open Access Journals (Sweden)

    Jochen eVandenbossche

    2013-01-01

    Full Text Available Recent studies emphasize a key role of controlled operations, such as set-shifting and inhibition, in the occurrence of freezing of gait (FOG in Parkinson’s disease (PD. However, FOG can also be characterized as a de-automatization disorder, showing impairments in both the execution and acquisition of automaticity. The observed deficits in automaticity and executive functioning indicate that both processes are malfunctioning in freezers. Therefore, to explain FOG from a cognitive-based perspective, we present a model describing the pathways involved in automatic and controlled processes prior to a FOG episode. Crucially, we focus on disturbances in automaticity and control, regulated by the frontostriatal circuitry. In complex situations, non-freezing PD patients may compensate for deficits in automaticity by switching to increased cognitive control. However, as both automatic and controlled processes are more severely impaired in freezers, this hampers cognitive compensation in FOG, resulting in a potential breakdown. Future directions for cognitive rehabilitation are proposed, based on the cognitive model we put forward.

  18. A new PID controller design for automatic generation control of hydro power systems

    Energy Technology Data Exchange (ETDEWEB)

    Khodabakhshian, A.; Hooshmand, R. [Electrical Engineering Department, University of Isfahan (Iran)

    2010-06-15

    This paper presents a new robust PID controller for automatic generation control (AGC) of hydro turbine power systems. The method is mainly based on a maximum peak resonance specification that is graphically supported by the Nichols chart. The open-loop frequency response curve is tangent to a specified ellipse and this makes the method to be efficient for controlling the overshoot, the stability and the dynamics of the system. Comparative results of this new load frequency controller with a conventional PI one and also with another PID controller design tested on a multimachine power system show the improvement in system damping remarkably. The region of acceptable performance of the new PID controller covers a wide range of operating and system conditions. (author)

  19. Automatic Generation Control Using PI Controller with Bacterial Foraging for both Thermal and Hydro Plants

    Directory of Open Access Journals (Sweden)

    Preeti Hooda,

    2014-06-01

    Full Text Available The load-frequency control (LFC is used to restore the balance between load and generation in each control area by means of speed control. In power system, the main goal of load frequency control (LFC or automatic generation control (AGC is to maintain the frequency of each area and tie- line power flow within specified tolerance by adjusting the MW outputs of LFC generators so as to accommodate fluctuating load demands. In this paper, attempt is made to make a scheme for automatic generation control within a restructured environment considering effects of contracts between DISCOs and GENCOs to make power system network in normal state where, GENCO used are hydro plants as well as thermal plants. The bacterial foraging optimization technique is being developed, which is applied to AGC in an interconnected four area system.The performance of the system is obtained by MATLAB Simulink tool. The results are shown in frequency and power response for four area AGC system. In this paper we have shown practical work by using thermal and hydro both system at Genco’s side.As reheated system transfer function is being used.

  20. ISS Contingency Attitude Control Recovery Method for Loss of Automatic Thruster Control

    Science.gov (United States)

    Bedrossian, Nazareth; Bhatt, Sagar; Alaniz, Abran; McCants, Edward; Nguyen, Louis; Chamitoff, Greg

    2008-01-01

    In this paper, the attitude control issues associated with International Space Station (ISS) loss of automatic thruster control capability are discussed and methods for attitude control recovery are presented. This scenario was experienced recently during Shuttle mission STS-117 and ISS Stage 13A in June 2007 when the Russian GN&C computers, which command the ISS thrusters, failed. Without automatic propulsive attitude control, the ISS would not be able to regain attitude control after the Orbiter undocked. The core issues associated with recovering long-term attitude control using CMGs are described as well as the systems engineering analysis to identify recovery options. It is shown that the recovery method can be separated into a procedure for rate damping to a safe harbor gravity gradient stable orientation and a capability to maneuver the vehicle to the necessary initial conditions for long term attitude hold. A manual control option using Soyuz and Progress vehicle thrusters is investigated for rate damping and maneuvers. The issues with implementing such an option are presented and the key issue of closed-loop stability is addressed. A new non-propulsive alternative to thruster control, Zero Propellant Maneuver (ZPM) attitude control method is introduced and its rate damping and maneuver performance evaluated. It is shown that ZPM can meet the tight attitude and rate error tolerances needed for long term attitude control. A combination of manual thruster rate damping to a safe harbor attitude followed by a ZPM to Stage long term attitude control orientation was selected by the Anomaly Resolution Team as the alternate attitude control method for such a contingency.

  1. Development of a microcontroller-based automatic control system for the electrohydraulic total artificial heart.

    Science.gov (United States)

    Kim, H C; Khanwilkar, P S; Bearnson, G B; Olsen, D B

    1997-01-01

    An automatic physiological control system for the actively filled, alternately pumped ventricles of the volumetrically coupled, electrohydraulic total artificial heart (EHTAH) was developed for long-term use. The automatic control system must ensure that the device: 1) maintains a physiological response of cardiac output, 2) compensates for an nonphysiological condition, and 3) is stable, reliable, and operates at a high power efficiency. The developed automatic control system met these requirements both in vitro, in week-long continuous mock circulation tests, and in vivo, in acute open-chested animals (calves). Satisfactory results were also obtained in a series of chronic animal experiments, including 21 days of continuous operation of the fully automatic control mode, and 138 days of operation in a manual mode, in a 159-day calf implant.

  2. Gain-controlled erbium-doped fiber amplifier using mode-selective photonic lantern

    Science.gov (United States)

    Lopez-Galmiche, G.; Sanjabi Eznaveh, Z.; Antonio-Lopez, J. E.; Velazquez-Benitez, A. M.; Rodriguez-Asomoza, J.; Herrera-Piad, L. A.; Sanchez-Mondragon, J. J.; Gonent, C.; Sillard, P.; Li, G.; SchuÌlzgen, A.; Okonkwo, C.; Amezcua Correa, R.

    2016-02-01

    For the first time, we demonstrate the implementation of a core pumped few mode erbium amplifier utilizing a mode selective photonic lantern for spatial modal control of the pump light. This device is able to individually amplify the first six fiber modes with low differential modal gain. In addition, we obtained differential modal gain lower than 1 dB and signal gain of approximately 16.17 dB at λs = 1550 nm through forward pumping the LP21 modes at λp = 976 nm.

  3. Automatic sleep staging using state machine-controlled decision trees.

    Science.gov (United States)

    Imtiaz, Syed Anas; Rodriguez-Villegas, Esther

    2015-01-01

    Automatic sleep staging from a reduced number of channels is desirable to save time, reduce costs and make sleep monitoring more accessible by providing home-based polysomnography. This paper introduces a novel algorithm for automatic scoring of sleep stages using a combination of small decision trees driven by a state machine. The algorithm uses two channels of EEG for feature extraction and has a state machine that selects a suitable decision tree for classification based on the prevailing sleep stage. Its performance has been evaluated using the complete dataset of 61 recordings from PhysioNet Sleep EDF Expanded database achieving an overall accuracy of 82% and 79% on training and test sets respectively. The algorithm has been developed with a very small number of decision tree nodes that are active at any given time making it suitable for use in resource-constrained wearable systems.

  4. The Automatic and Controlled Processing of Temporal and Spatial Patterns.

    Science.gov (United States)

    1980-02-01

    Atkinson and Juola, 1973; Slhffrin and Geisler, 1973; and Corballis, 1975; Posner and Snyder, 1975). Schneider and Shiffrin (1977; Shiffrin and Schneider...Besides the frame size, Schneider and Shiffrin (1977) also varied the memory set size to study the differential load requirements of CM and VM...theoretical level, Shiffrin and Schneider (1977) described an automatic process as a sequence of memory nodes that nearly always become active in

  5. Analysis and design of sliding mode controller gains for boost power factor corrector.

    Science.gov (United States)

    Kessal, Abdelhalim; Rahmani, Lazhar

    2013-09-01

    This paper presents a systematic procedure to compute the gains of sliding mode controller based on an optimization scheme. This controller is oriented to drive an AC-DC converter operating in continuous mode with power factor near unity, and in order to improve static and dynamic performances with large variations of reference voltage and load. This study shows the great influence of the controller gains on the global performances of the system. Hence, a methodology for choosing the gains is detailed. The sliding surface used in this study contains two state variables, input current and output voltage; the advantage of this surface is getting reactions against various disturbances-at the power source, the reference of the output, or the value of the load. The controller is experimentally confirmed for steady-state performance and transient response.

  6. Adaptive fuzzy dynamic surface control for the chaotic permanent magnet synchronous motor using Nussbaum gain

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Shaohua [School of Automation, Chongqing University, Chongqing 400044, China and College of Mechanical Engineering, Hunan University of Arts and Science, Hunan 415000 (China)

    2014-09-01

    This paper is concerned with the problem of adaptive fuzzy dynamic surface control (DSC) for the permanent magnet synchronous motor (PMSM) system with chaotic behavior, disturbance and unknown control gain and parameters. Nussbaum gain is adopted to cope with the situation that the control gain is unknown. And the unknown items can be estimated by fuzzy logic system. The proposed controller guarantees that all the signals in the closed-loop system are bounded and the system output eventually converges to a small neighborhood of the desired reference signal. Finally, the numerical simulations indicate that the proposed scheme can suppress the chaos of PMSM and show the effectiveness and robustness of the proposed method.

  7. Reliable gain-scheduled control of discrete-time systems and its application to CSTR model

    Science.gov (United States)

    Sakthivel, R.; Selvi, S.; Mathiyalagan, K.; Shi, Y.

    2016-10-01

    This paper is focused on reliable gain-scheduled controller design for a class of discrete-time systems with randomly occurring nonlinearities and actuator fault. Further, the nonlinearity in the system model is assumed to occur randomly according to a Bernoulli distribution with measurable time-varying probability in real time. The main purpose of this paper is to design a gain-scheduled controller by implementing a probability-dependent Lyapunov function and linear matrix inequality (LMI) approach such that the closed-loop discrete-time system is stochastically stable for all admissible randomly occurring nonlinearities. The existence conditions for the reliable controller is formulated in terms of LMI constraints. Finally, the proposed reliable gain-scheduled control scheme is applied on continuously stirred tank reactor model to demonstrate the effectiveness and applicability of the proposed design technique.

  8. Adaptive control of linear multivariable systems with high frequency gain matrix hurwitz

    Institute of Scientific and Technical Information of China (English)

    Ying ZHOU; Yuqiang WU; Shumin FEI

    2005-01-01

    A new adaptive control scheme is proposed for multivariable model reference adaptive control(MRAC) systems based on the nonlinear backstepping approach with vector form.The assumption on a priori knowledge of the high frequency gain matrix in existing results is relaxed and the new required condition for the high frequency gain matrix can be easily checked for certain plants so that the proposed method is widely applicable.This control scheme guarantees the global stability of the closed-loop systems and the tracking error can be arbitrary small.The simulation result for an application example shows the validity of the proposed nonlinear adaptive scheme.

  9. Gain-scheduled Linear Quadratic Control of Wind Turbines Operating at High Wind Speed

    DEFF Research Database (Denmark)

    Østergaard, Kasper Zinck; Stoustrup, Jakob; Brath, Per

    2007-01-01

    This paper addresses state estimation and linear quadratic (LQ) control of variable speed variable pitch wind turbines. On the basis of a nonlinear model of a wind turbine, a set of operating conditions is identified and a LQ controller is designed for each operating point. The controller gains....... Simulation results are given that display good performance of the observers and comparisons with a controller designed by classical methods displays the potential of the method.  ...

  10. Gain Scheduling Control of Nonlinear Systems Based on Neural State Space Models

    DEFF Research Database (Denmark)

    Bendtsen, Jan Dimon; Stoustrup, Jakob

    2003-01-01

    This paper presents a novel method for gain scheduling control of nonlinear systems based on extraction of local linear state space models from neural networks with direct application to robust control. A neural state space model of the system is first trained based on in- and output training...

  11. Tailoring automatic exposure control toward constant detectability in digital mammography

    Energy Technology Data Exchange (ETDEWEB)

    Salvagnini, Elena, E-mail: elena.salvagnini@uzleuven.be [Department of Imaging and Pathology, Medical Physics and Quality Assessment, KUL, Herestraat 49, Leuven B-3000, Belgium and SCK-CEN, Boeretang 200, Mol 2400 (Belgium); Bosmans, Hilde [Department of Imaging and Pathology, Medical Physics and Quality Assessment, KUL, Herestraat 49, Leuven B-3000, Belgium and Department of Radiology, UZ Gasthuisberg, Herestraat 49, Leuven B-3000 (Belgium); Struelens, Lara [SCK-CEN, Boeretang 200, Mol 2400 (Belgium); Marshall, Nicholas W. [Department of Radiology, UZ Gasthuisberg, Herestraat 49, Leuven B-3000 (Belgium)

    2015-07-15

    Purpose: The automatic exposure control (AEC) modes of most full field digital mammography (FFDM) systems are set up to hold pixel value (PV) constant as breast thickness changes. This paper proposes an alternative AEC mode, set up to maintain some minimum detectability level, with the ultimate goal of improving object detectability at larger breast thicknesses. Methods: The default “OPDOSE” AEC mode of a Siemens MAMMOMAT Inspiration FFDM system was assessed using poly(methyl methacrylate) (PMMA) of thickness 20, 30, 40, 50, 60, and 70 mm to find the tube voltage and anode/filter combination programmed for each thickness; these beam quality settings were used for the modified AEC mode. Detectability index (d′), in terms of a non-prewhitened model observer with eye filter, was then calculated as a function of tube current-time product (mAs) for each thickness. A modified AEC could then be designed in which detectability never fell below some minimum setting for any thickness in the operating range. In this study, the value was chosen such that the system met the achievable threshold gold thickness (T{sub t}) in the European guidelines for the 0.1 mm diameter disc (i.e., T{sub t} ≤ 1.10 μm gold). The default and modified AEC modes were compared in terms of contrast-detail performance (T{sub t}), calculated detectability (d′), signal-difference-to-noise ratio (SDNR), and mean glandular dose (MGD). The influence of a structured background on object detectability for both AEC modes was examined using a CIRS BR3D phantom. Computer-based CDMAM reading was used for the homogeneous case, while the images with the BR3D background were scored by human observers. Results: The default OPDOSE AEC mode maintained PV constant as PMMA thickness increased, leading to a reduction in SDNR for the homogeneous background 39% and d′ 37% in going from 20 to 70 mm; introduction of the structured BR3D plate changed these figures to 22% (SDNR) and 6% (d′), respectively

  12. An Evaluation of Automatic Control System Concepts for General Aviation Airplanes

    Science.gov (United States)

    Stewart, E. C.

    1990-01-01

    A piloted simulation study of automatic longitudinal control systems for general aviation airplanes has been conducted. These automatic control systems were designed to make the simulated airplane easy to fly for a beginning or infrequent pilot. Different control systems are presented and their characteristics are documented. In a conventional airplane control system each cockpit controller commands combinations of both the airspeed and the vertical speed. The best system in the present study decoupled the airspeed and vertical speed responses to cockpit controller inputs. An important feature of the automatic system was that neither changing flap position nor maneuvering in steeply banked turns affected either the airspeed or the vertical speed. All the pilots who flew the control system simulation were favorably impressed with the very low workload and the excellent handling qualities of the simulated airplane.

  13. Noise Temperature Characteristics and Gain-control of Avalanche Photodiodes for Laser Radar

    Institute of Scientific and Technical Information of China (English)

    CAI Xi-ping; SHANG Hong-Bo; BAI Ji-yuan; YANG Shuang; WANG Li-na

    2008-01-01

    Avalanche photodiodes(APDs) are promising light sensors with high quantum efficiency and low noise. It has been extensively used in radiation detection, laser radar and other weak signal detection fields. Unlike other photodiodes, APD is a very sensitive light detector with very high internal gain. The basic theory shows that the gain of APD is related to the temperature. The internal gain fluctuates with the variation of temperature. Investigated was the influence of the variation of the gain induced by the fluctuation of temperature on the output from APD for a very weak laser pulse input in laser radar. An active reverse-biased voltage compensation method is used to stabilize the gain of APD. An APD model is setup to simulate the detection of light pulse signal. The avalanche process, various noises and temperature's effect are all included in the model. Our results show that for the detection of weak light signal such as in laser radar, even a very small fluctuation of temperature could cause a great effect on APD's gain. The results show that the signal-to-noise ratio of the APD's output could be improved effectively with the active gain-control system.

  14. L∞-gain adaptive fuzzy fault accommodation control design for nonlinear time-delay systems.

    Science.gov (United States)

    Wu, Huai-Ning; Qiang, Xiao-Hong; Guo, Lei

    2011-06-01

    In this paper, an adaptive fuzzy fault accommodation (FA) control design with a guaranteed L(∞)-gain performance is developed for a class of nonlinear time-delay systems with persistent bounded disturbances. Using the Lyapunov technique and the Razumikhin-type lemma, the existence condition of the L(∞) -gain adaptive fuzzy FA controllers is provided in terms of linear matrix inequalities (LMIs). In the proposed FA scheme, a fuzzy logic system is employed to approximate the unknown term in the derivative of the Lyapunov function due to the unknown fault function; a continuous-state feedback control strategy is adopted for the control design to avoid the undesirable chattering phenomenon. The resulting FA controllers can ensure that every response of the closed-loop system is uniformly ultimately bounded with a guaranteed L(∞)-gain performance in the presence of a fault. Moreover, by the existing LMI optimization technique, a suboptimal controller is obtained in the sense of minimizing an upper bound of the L(∞)-gain. Finally, the achieved simulation results on the FA control of a continuous stirred tank reactor (CSTR) show the effectiveness of the proposed design procedure.

  15. Automatic flatness control strategy with a Smith predictor for steel strip rolling

    Science.gov (United States)

    Zhang, Ruicheng; Zheng, Xin

    2011-10-01

    The simplified transfer function diagram block for a automatic flatness control (AFC) system of strip steel rolling process was investigated. For the problem of automatic flatness control (AFC) in cold tandem mills this paper proposes control techniques based on Smith predictor to compensate for the numerous delays present in the mill. After a Smith predictor was used to the AFC system, the control laws were deduced for both proportional and integral regulators. Control algorithms are tested in simulation considering a tandem mill with four stands as a benchmark, and results are shown to demonstrate the performance of the proposed schemes.

  16. General collaboration offer of Johnson Controls regarding the performance of air conditioning automatic control systems and other buildings` automatic control systems

    Energy Technology Data Exchange (ETDEWEB)

    Gniazdowski, J.

    1995-12-31

    JOHNSON CONTROLS manufactures measuring and control equipment (800 types) and is as well a {open_quotes}turn-key{close_quotes} supplier of complete automatic controls systems for heating, air conditioning, ventilation and refrigerating engineering branches. The Company also supplies Buildings` Computer-Based Supervision and Monitoring Systems that may be applied in both small and large structures. Since 1990 the company has been performing full-range trade and contracting activities on the Polish market. We have our own well-trained technical staff and we collaborate with a series of designing and contracting enterprises that enable us to have our projects carried out all over Poland. The prices of our supplies and services correspond with the level of the Polish market.

  17. Automatic SIMD vectorization of SSA-based control flow graphs

    CERN Document Server

    Karrenberg, Ralf

    2015-01-01

    Ralf Karrenberg presents Whole-Function Vectorization (WFV), an approach that allows a compiler to automatically create code that exploits data-parallelism using SIMD instructions. Data-parallel applications such as particle simulations, stock option price estimation or video decoding require the same computations to be performed on huge amounts of data. Without WFV, one processor core executes a single instance of a data-parallel function. WFV transforms the function to execute multiple instances at once using SIMD instructions. The author describes an advanced WFV algorithm that includes a v

  18. Adaptive Fuzzy Robust Control for a Class of Nonlinear Systems via Small Gain Theorem

    Directory of Open Access Journals (Sweden)

    Xingjian Wang

    2013-01-01

    Full Text Available Practical nonlinear systems can usually be represented by partly linearizable models with unknown nonlinearities and external disturbances. Based on this consideration, we propose a novel adaptive fuzzy robust control (AFRC algorithm for such systems. The AFRC effectively combines techniques of adaptive control and fuzzy control, and it improves the performance by retaining the advantages of both methods. The linearizable part will be linearly parameterized with unknown but constant parameters, and the discontinuous-projection-based adaptive control law is used to compensate these parts. The Takagi-Sugeno fuzzy logic systems are used to approximate unknown nonlinearities. Robust control law ensures the robustness of closed-loop control system. A systematic design procedure of the AFRC algorithm by combining the backstepping technique and small-gain approach is presented. Then the closed-loop stability is studied by using small gain theorem, and the result indicates that the closed-loop system is semiglobally uniformly ultimately bounded.

  19. [Automatization of microscopic blood smear analyses and quality control using reference virtual slides].

    Science.gov (United States)

    Medovyĭ, V S; Nikolaenko, D S; Parpara, A A; Piatnitskiĭ, A M; Sokolinskiĭ, B Z; Dem'ianov, V L; Zhurkina, T V; Pal'chunova, I B

    2008-06-01

    MEKOC microscopy complexes have a group of specialized automatic functions for medical analyses of biomaterials integrated with general virtual microscopy accessories. Such functions provide a way of making specialized reference virtual slides (RVS). The latter contain the results of virtual analysis or expert evidence of the automatic analysis results presented in the virtual slide. The use of RVS yields an open system with a step-by-step control of the quality of automatic operations. RVS as realistic preparation models are also used to train staff. The results of step-by-step trials of the MEKOC--2 are presented in the paper.

  20. Sliding mode control of wind-induced vibrations using fuzzy sliding surface and gain adaptation

    Science.gov (United States)

    Thenozhi, Suresh; Yu, Wen

    2016-04-01

    Although fuzzy/adaptive sliding mode control can reduce the chattering problem in structural vibration control applications, they require the equivalent control and the upper bounds of the system uncertainties. In this paper, we used fuzzy logic to approximate the standard sliding surface and designed a dead-zone adaptive law for tuning the switching gain of the sliding mode control. The stability of the proposed controller is established using Lyapunov stability theory. A six-storey building prototype equipped with an active mass damper has been used to demonstrate the effectiveness of the proposed controller towards the wind-induced vibrations.

  1. A closed-loop automatic control system for high-intensity acoustic test systems.

    Science.gov (United States)

    Slusser, R. A.

    1973-01-01

    Sound at sound pressure levels in the range from 130 to 160 dB is used in the investigation. Random noise is passed through a series of parallel filters, generally 1/3-octave wide. A basic automatic system is investigated because of preadjustment inaccuracies and high costs found in a study of a typical manually controlled acoustic testing system. The unit described has been successfully used in automatic acoustic tests in connection with the spacecraft tests for the Mariner 1971 program.

  2. A Computer-controlled, Fully Automatic NMR/NQR Double Resonance Spectrometer

    Science.gov (United States)

    Zhenye, Feng; Lücken, Edwin A. C.; Diolot, Jacques

    1992-02-01

    A completely automatic computer-controlled NMR/NQR double resonance spectrometer is described. It features automatic tuning of the low, variable frequency power amplifier, thus permitting untended use over long periods, with high sensitivity and signal reproducibility. The sample is transferred between the low-frequency, zero-field region and the high-field region using compressed air and the possibility of switching on a field of several tens of gauss during the transfer of the sample is also included

  3. On the Existence of an Optimal Control of Ship Automatic Steering Instruments

    Institute of Scientific and Technical Information of China (English)

    GAO Cunchen; GUO Jifeng

    2005-01-01

    The existence of linear quadratic optimal control of ship automatic steering instruments is studied. Firstly, the sufficient conditions for the quadratic integrability of the solutions of linear second order time-variant differential equations are developed. Secondly, the optimal control form of the ship automatic steering instrument is obtained by using the dynamic programming method, which guarantees a minimal ship sway range, during long-distance navigation, by using as little energy as possible. Finally, based on the above mentioned sufficient conditions, the conditions for the realization of optimal control are obtained, which provides a foundation for choosing the weighted coefficients for optimal control in engineering.

  4. Flight Investigation of the Effectiveness of an Automatic Aileron Trim Control Device for Personal Airplanes

    Science.gov (United States)

    Phillips, William H; Kuehnel, Helmut A; Whitten, James B

    1957-01-01

    A flight investigation to determine the effectiveness of an automatic aileron trim control device installed in a personal airplane to augment the apparent spiral stability has been conducted. The device utilizes a rate-gyro sensing element in order to switch an on-off type of control that operates the ailerons at a fixed rate through control centering springs. An analytical study using phase-plane and analog-computer methods has been carried out to determine a desirable method of operation for the automatic trim control.

  5. Controlling automatic imitative tendencies: interactions between mirror neuron and cognitive control systems.

    Science.gov (United States)

    Cross, Katy A; Torrisi, Salvatore; Reynolds Losin, Elizabeth A; Iacoboni, Marco

    2013-12-01

    Humans have an automatic tendency to imitate others. Although several regions commonly observed in social tasks have been shown to be involved in imitation control, there is little work exploring how these regions interact with one another. We used fMRI and dynamic causal modeling to identify imitation-specific control mechanisms and examine functional interactions between regions. Participants performed a pre-specified action (lifting their index or middle finger) in response to videos depicting the same two actions (biological cues) or dots moving with similar trajectories (non-biological cues). On congruent trials, the stimulus and response were similar (e.g. index finger response to index finger or left side dot stimulus), while on incongruent trials the stimulus and response were dissimilar (e.g. index finger response to middle finger or right side dot stimulus). Reaction times were slower on incongruent compared to congruent trials for both biological and non-biological stimuli, replicating previous findings that suggest the automatic imitative or spatially compatible (congruent) response must be controlled on incongruent trials. Neural correlates of the congruency effects were different depending on the cue type. The medial prefrontal cortex, anterior cingulate, inferior frontal gyrus pars opercularis (IFGpo) and the left anterior insula were involved specifically in controlling imitation. In addition, the IFGpo was also more active for biological compared to non-biological stimuli, suggesting that the region represents the frontal node of the human mirror neuron system (MNS). Effective connectivity analysis exploring the interactions between these regions, suggests a role for the mPFC and ACC in imitative conflict detection and the anterior insula in conflict resolution processes, which may occur through interactions with the frontal node of the MNS. We suggest an extension of the previous models of imitation control involving interactions between imitation

  6. Output feedback adaptive control of multivariable nonlinear systems using Nussbaum gain method

    Institute of Scientific and Technical Information of China (English)

    Zhou Ying; Wu Yuqiang

    2006-01-01

    A new output feedback adaptive control scheme for multi-input and multi-output nonlinear systems with parametric uncertainty is presented based on the Nussbaum gain method and the backstepping approach. The high frequency gain matrix of the linear part of the system is not necessarily positive definite, but can be transformed into a lower or upper triangular matrix whose signs of diagonal elements are unknown. The new required condition for the high frequency gain matrix can be easily checked for certain plants so that the proposed method is widely applicable. The global stability of the closed loop systems is guaranteed through this control scheme, at the same time the tracking error converges to zero.

  7. Automatic Generation Control Strategy Based on Balance of Daily Electric Energy

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    An automatic generation control strategy based on balance of daily total electric energy is put forward. It makes the balance between actual total generated energy controlled by automatic generation system and planned total energy on base of area control error, and makes the actual 24-hour active power load curve to approach the planned load curve. The generated energy is corrected by velocity weighting factor so that it conducts dynamic regulation and reaches the speed of response. Homologous strategy is used according to the real-time data in the operation of automatic generation control. Results of simulation are perfect and power energy compensation control with ideal effect can be achieved in the particular duration.

  8. Analysis and Design of PLC-based Control System for Automatic Beverage Filling Machine

    Directory of Open Access Journals (Sweden)

    Yundan Lu

    2015-01-01

    Full Text Available Automatic filling system is the main equipment in the food machinery industry. With the development of beverage industry and increasing demand of the filling system. The relay control method in traditional Filling machine has low automation and integration level and cannot satisfy the rapid development of automatic production. PLC control method has advantages of simple programming, strong anti-interference and high working reliability, has gradually replace the relay control method. In this study, hardware and software for the automatic filling system based on PLC control is designed, especially the injection section servo control system which adopts the servo motor driver metering pump is carefully analyzed and the filling precision is highly improved.

  9. Specific predictive power of automatic spider-related affective associations for controllable and uncontrollable fear responses toward spiders

    NARCIS (Netherlands)

    J. Huijding (Jorg); P.J. de Jong (Peter)

    2006-01-01

    textabstractThis study examined the predictive power of automatically activated spider-related affective associations for automatic and controllable fear responses. The Extrinsic Affective Simon Task (EAST; De Houwer, 2003) was used to indirectly assess automatic spider fear-related associations. Th

  10. Specific predictive power of automatic spider-related affective associations for controllable and uncontrollable fear responses toward spiders

    NARCIS (Netherlands)

    Huijdlng, J; de Jong, PJ; Huijding, J.

    2006-01-01

    This study examined the predictive power of automatically activated spider-related affective associations for automatic and controllable fear responses. The Extrinsic Affective Simon Task (EAST; De Houwer, 2003) was used to indirectly assess automatic spider fear-related associations. The EAST and t

  11. Man-system interface based on automatic speech recognition: integration to a virtual control desk

    Energy Technology Data Exchange (ETDEWEB)

    Jorge, Carlos Alexandre F.; Mol, Antonio Carlos A.; Pereira, Claudio M.N.A.; Aghina, Mauricio Alves C., E-mail: calexandre@ien.gov.b, E-mail: mol@ien.gov.b, E-mail: cmnap@ien.gov.b, E-mail: mag@ien.gov.b [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Nomiya, Diogo V., E-mail: diogonomiya@gmail.co [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil)

    2009-07-01

    This work reports the implementation of a man-system interface based on automatic speech recognition, and its integration to a virtual nuclear power plant control desk. The later is aimed to reproduce a real control desk using virtual reality technology, for operator training and ergonomic evaluation purpose. An automatic speech recognition system was developed to serve as a new interface with users, substituting computer keyboard and mouse. They can operate this virtual control desk in front of a computer monitor or a projection screen through spoken commands. The automatic speech recognition interface developed is based on a well-known signal processing technique named cepstral analysis, and on artificial neural networks. The speech recognition interface is described, along with its integration with the virtual control desk, and results are presented. (author)

  12. Towards automatic model based controller design for reconfigurable plants

    DEFF Research Database (Denmark)

    Michelsen, Axel Gottlieb; Stoustrup, Jakob; Izadi-Zamanabadi, Roozbeh

    2008-01-01

    This paper introduces model-based Plug and Play Process Control, a novel concept for process control, which allows a model-based control system to be reconfigured when a sensor or an actuator is plugged into a controlled process. The work reported in this paper focuses on composing a monolithic m...

  13. AUTOMATIC CONTROL SYSTEM OF THE DRUM BOILER SUPERHEATED STEAM TEMPERATURE.

    Directory of Open Access Journals (Sweden)

    Juravliov A.A.

    2006-04-01

    Full Text Available The control system of the temperature of the superheated steam of the drum boiler is examined. Main features of the system are the PI-controller in the external control loop and introduction of the functional component of the error signal of the external control loop with the negative feedback of the error signal between the prescribed value of steam flowrate and the signal of the steam flowrate in the exit of the boiler in the internal control loop.

  14. Adaptive-Gain Second-Order Sliding Mode Control of Attitude Tracking of Flexible Spacecraft

    Directory of Open Access Journals (Sweden)

    Chutiphon Pukdeboon

    2014-01-01

    finite-time second-order sliding mode control algorithms are presented to solve this problem. For the first controller, a novel second-order sliding mode control scheme is developed to achieve high-precision tracking performance. For the second control law, an adaptive-gain second-order sliding mode control algorithm combing an adaptive law with second-order sliding mode control strategy is designed to relax the requirement of prior knowledge of the bound of the system uncertainties. The rigorous proofs show that the proposed controllers provide finite-time convergence of the attitude and angular velocity tracking errors. Numerical simulations on attitude tracking control are presented to demonstrate the performance of the developed controllers.

  15. Automatic Weight Selection Algorithm for Designing H Infinity controller for Active Magnetic Bearing

    Directory of Open Access Journals (Sweden)

    Sarath S Nair

    2011-01-01

    Full Text Available In recent times active magnetic bearing has got wide acceptance in industries and other special systems. Current researches focus on improving the disturbance rejection properties of magnetic bearings towork well in industrial environment. So far many controllers have been developed to control the system, of which the H∞ controller is found to guarantee robustness and performance. In this paper an automatic weight selection algorithm is proposed to design robust H Infinity controller automatically for active magnetic bearing system and detailed disturbance analysis is done. This paper focuses on the controller implementation point of view and analyses the variation in control current, peak responses and steady state error of the developed controller. Comparison with a well tuned PID controller shows the efficacy of H infinity controller designed using the proposed algorithm.

  16. LNA with wide range of gain control and wideband interference rejection

    Science.gov (United States)

    Wang, Jhen-Ji; Chen, Duan-Yu

    2016-10-01

    This work presents a low-noise amplifier (LNA) design with a wide-range gain control characteristic that integrates adjustable current distribution and output impedance techniques. For a given gain characteristic, the proposed LNA provides better wideband interference rejection performance than conventional LNA. Moreover, the proposed LNA also has a wider gain control range than conventional LNA. Therefore, it is suitable for satellite communications systems. The simulation results demonstrate that the voltage gain control range is between 14.5 and 34.2 dB for such applications (2600 MHz); the input reflection coefficient is less than -18.9 dB; the noise figure (NF) is 1.25 dB; and the third-order intercept point (IIP3) is 4.52 dBm. The proposed LNA consumes 23.85-28.17 mW at a supply voltage of 1.8 V. It is implemented by using TSMC 0.18-um RF CMOS process technology.

  17. Percutaneous endoscopic gastrostomy under steadypressure automatically controlled endoscopy: First clinicalseries

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    AIM To elucidate the safety of percutaneous endoscopicgastrostomy (PEG) under steady pressure automaticallycontrolled endoscopy (SPACE) using carbon dioxide (CO2). METHODS: Nine patients underwent PEG with a modifiedintroducer method under conscious sedation. A T-tubewas attached to the channel of an endoscope connectedto an automatic surgical insufflator. The stomach wasinflated under the SPACE system. The intragastricpressure was kept between 4-8 mmHg with a flow of CO2at 35 L/min. Median procedure time, intragastric pressure,median systolic blood pressure, partial pressure of CO2,abdominal girth before and immediately after PEG, andfree gas and small intestinal gas on abdominal X-raybefore and after PEG were recorded.RESULTS: PEG was completed under stable pneumostomachin all patients, with a median procedural timeof 22 min. Median intragastric pressure was 6.9 mmHgand median arterial CO2 pressure before and after PEGwas 42.1 and 45.5 Torr (NS). The median abdominal girthbefore and after PEG was 68.1 and 69.6 cm (NS). A mildfree gas image after PEG was observed in two patients,and faint abdominal gas in the downstream bowel wasdocumented in two patients.CONCLUSION: SPACE might enable standardized pneumostomachand modified introducer procedure of PEG.

  18. Eye movements in pedophiles: automatic and controlled attentional processes while viewing prepubescent stimuli.

    Science.gov (United States)

    Fromberger, Peter; Jordan, Kirsten; Steinkrauss, Henrike; von Herder, Jakob; Stolpmann, Georg; Kröner-Herwig, Birgit; Müller, Jürgen Leo

    2013-05-01

    Recent theories in sexuality highlight the importance of automatic and controlled attentional processes in viewing sexually relevant stimuli. The model of Spiering and Everaerd (2007) assumes that sexually relevant features of a stimulus are preattentively selected and automatically induce focal attention to these sexually relevant aspects. Whether this assumption proves true for pedophiles is unknown. It is aim of this study to test this assumption empirically for people suffering from pedophilic interests. Twenty-two pedophiles, 8 nonpedophilic forensic controls, and 52 healthy controls simultaneously viewed the picture of a child and the picture of an adult while eye movements were measured. Entry time was assessed as a measure of automatic attentional processes and relative fixation time in order to assess controlled attentional processes. Pedophiles demonstrated significantly shorter entry time to child stimuli than to adult stimuli. The opposite was the case for nonpedophiles, as they showed longer relative fixation time for adult stimuli, and, against all expectations, pedophiles also demonstrated longer relative fixation time for adult stimuli. The results confirmed the hypothesis that pedophiles automatically selected sexually relevant stimuli (children). Contrary to all expectations, this automatic selection did not trigger the focal attention to these sexually relevant pictures. Furthermore, pedophiles were first and longest attracted by faces and pubic regions of children; nonpedophiles were first and longest attracted by faces and breasts of adults. The results demonstrated, for the first time, that the face and pubic region are the most attracting regions in children for pedophiles.

  19. A new portable device for automatic controlled-gradient cryopreservation of blood mononuclear cells

    DEFF Research Database (Denmark)

    Hviid, L; Albeck, G; Hansen, B

    1993-01-01

    , which has proved suitable for field conditions. We report here the development and testing of a similar micro-controller regulated device, allowing unattended and automatic controlled-gradient cell freezing. The equipment exploits the temperature gradient present between the liquid N2 surface...

  20. 75 FR 80886 - Ninth Meeting-RTCA Special Committee 220: Automatic Flight Guidance and Control

    Science.gov (United States)

    2010-12-23

    ... Federal Aviation Administration Ninth Meeting--RTCA Special Committee 220: Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of RTCA Special Committee 220... and Control meeting. The agenda will include: Welcome/Agenda Overview. Presentation of progress WG...

  1. Initial ideas for automatic design and verification of control logic in reversible HDLs

    DEFF Research Database (Denmark)

    Wille, Robert; Keszocze, Oliver; Othmer, Lars;

    2016-01-01

    not obvious. Moreover, implementations exist which may not be realized with a reversible control flow at all. In this work, we propose automatic methods for descriptions in the reversible HDL SyReC that can generate the required fi-conditions and check whether a reversible control flow indeed can be realized...

  2. Methods of Synthesis of Automatic Control Systems with Delay

    Directory of Open Access Journals (Sweden)

    Aliaksandr Lapeta

    2013-05-01

    Full Text Available The paper investigates the procedure for introduction of systems containing delay elements. Shortcomings and difficulties in the synthesis of regulators and precompensators of control systems with delays in output and control channel where determined. The author focused on two approaches for the formation of promatrix and synthesis of control systems, considering the factor of delay.

  3. Visual information gain and task asymmetry interact in bimanual force coordination and control.

    Science.gov (United States)

    Hu, Xiaogang; Newell, Karl M

    2011-08-01

    This study examined the question of whether and how the influence of visual information on force coordination patterns is dependent on the settings of a task asymmetry constraint. In a bimanual isometric force experiment, the task asymmetry was manipulated via imposing different coefficients on the index finger forces such that the weighted sum of the finger forces matched the target force. The environmental constraint was quantified by the visual performance error and was manipulated through the change of visual gain (number of pixels on the screen representing the unit of force). The constraint arising from the individual was quantified by the bilateral coupling effect (i.e., symmetric force production) between hands. The results revealed improved performance in terms of lower variability and performance error and more complex total force structure with higher visual gain. The influence of visual gain on the force coordination pattern, however, was found to be dependent on the task coefficients imposed on the finger forces. Namely, the force sharing between hands became more symmetric with high visual gain only when the right finger force had the higher coefficient, and an error-compensatory strategy was evident with high gain only when symmetric coefficients were imposed on the two fingers. The findings support the proposition that the motor coordination and control patterns are organized by the interactive influence of different categories of constraints where the functional influence of the information provided is dependent on the motor output.

  4. Automatic power control for KMRR using reactivity constraint method

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byung I.; Kim, Myung H. [Kyunghee University, Yongin (Korea, Republic of)

    1990-07-01

    The use of reactivity constraint approach for the non-linear, digital controller is described. The design of controller was done for Korea Multipurpose Research Reactor(KMRR) which is now under construction. The performance test showed that reactivity constraint approach is a fast and reliable means for reactor power change control. A new formulation of the dynamic period equation for 2-point kinetics model is presented. The instantaneous dynamic period is calculated by new equation and used for time optimal control. A new controller keeping up the allowed minimum reactor period shows effective and reliable performance for power change.

  5. Adaptive Robust Actuator Fault Accommodation for a Class of Uncertain Nonlinear Systems with Unknown Control Gains

    Directory of Open Access Journals (Sweden)

    Yuefei Wu

    2014-01-01

    Full Text Available An adaptive robust fault tolerant control approach is proposed for a class of uncertain nonlinear systems with unknown signs of high-frequency gain and unmeasured states. In the recursive design, neural networks are employed to approximate the unknown nonlinear functions, K-filters are designed to estimate the unmeasured states, and a dynamical signal and Nussbaum gain functions are introduced to handle the unknown sign of the virtual control direction. By incorporating the switching function σ algorithm, the adaptive backstepping scheme developed in this paper does not require the real value of the actuator failure. It is mathematically proved that the proposed adaptive robust fault tolerant control approach can guarantee that all the signals of the closed-loop system are bounded, and the output converges to a small neighborhood of the origin. The effectiveness of the proposed approach is illustrated by the simulation examples.

  6. Realization of the ergonomics design and automatic control of the fundus cameras

    Science.gov (United States)

    Zeng, Chi-liang; Xiao, Ze-xin; Deng, Shi-chao; Yu, Xin-ye

    2012-12-01

    The principles of ergonomics design in fundus cameras should be extending the agreeableness by automatic control. Firstly, a 3D positional numerical control system is designed for positioning the eye pupils of the patients who are doing fundus examinations. This system consists of a electronically controlled chin bracket for moving up and down, a lateral movement of binocular with the detector and the automatic refocusing of the edges of the eye pupils. Secondly, an auto-focusing device for the object plane of patient's fundus is designed, which collects the patient's fundus images automatically whether their eyes is ametropic or not. Finally, a moving visual target is developed for expanding the fields of the fundus images.

  7. Method and apparatus for automatic control of a humanoid robot

    Science.gov (United States)

    Abdallah, Muhammad E (Inventor); Platt, Robert (Inventor); Wampler, II, Charles W. (Inventor); Reiland, Matthew J (Inventor); Sanders, Adam M (Inventor)

    2013-01-01

    A robotic system includes a humanoid robot having a plurality of joints adapted for force control with respect to an object acted upon by the robot, a graphical user interface (GUI) for receiving an input signal from a user, and a controller. The GUI provides the user with intuitive programming access to the controller. The controller controls the joints using an impedance-based control framework, which provides object level, end-effector level, and/or joint space-level control of the robot in response to the input signal. A method for controlling the robotic system includes receiving the input signal via the GUI, e.g., a desired force, and then processing the input signal using a host machine to control the joints via an impedance-based control framework. The framework provides object level, end-effector level, and/or joint space-level control of the robot, and allows for functional-based GUI to simplify implementation of a myriad of operating modes.

  8. Auto gain control of EMCCD in Shack-Hartmann wavefront sensor for adaptive optics

    Science.gov (United States)

    Zhu, Zhaoyi; Li, Dayu; Hu, Lifa; Mu, QuanQuan; Cao, Zhaoliang; Wang, Yukun; Wang, Shaoxin; Xuan, Li

    2016-12-01

    Electron multiplying charge-coupled-device (EMCCD) applied in Shack-Hartmann wavefront sensor (S-H WFS) makes the wavefront sensing more efficient for adaptive optics (AO). However when the brightness of the observed target changes in large ranges in a few minutes, a fixed electron multiplying (EM) gain may not be optimum. Thus an auto-gain-control (AGC) method based on the spots image of the S-H WFS is proposed. The designed control value is the average value of the maximum signals of all the light spots in a frame. It has been demonstrated in the experiments that the control value is sensitive to the change of the target brightness, and is stable in the presence of detecting noises and turbulence influence. The goal value for control is predetermined based on the linear relation of the signal with the EM gain and the number of photons collected in sub-apertures. The conditions of the self-protection of the EMCCD are also considered for the goal value. Simulations and experiments indicate that the proposed control method is efficient, and keeps the sensing in a high SNR which reaches the upper SNR limit when sensing with EMCCD. The self-protection of the EMCCD is avoided during the whole sensing process.

  9. Methodology of automatic quality control of aluminium castings

    Directory of Open Access Journals (Sweden)

    J.H. Sokolowski

    2007-01-01

    Full Text Available Purpose: Employment of the artificial intelligence tools for development of the methodology of the automatedassessment of quality and structural defects in the Al and Mg alloys and the custom made computer softwarewill make it possible to determine the quality of the manufactured element based on the digital images registeredin the X-ray flaw detection examinations. The possibility to correlate the frequency and morphology of defectswith the technological process parameters will make it also possible to identify and classify these defects andcontrol the process to minimise and eliminate them.Design/methodology/approach: The developed design methodologies both the material and technologicalones will make it possible to improve shortly the quality of materials from the light alloys in the technologicalprocess, and the automatic process flow correction will make the production cost reduction possible, and - firstof all - to reduce the amount of the waste products.Findings: The merit of the project consists in the interdisciplinary joining of the knowledge in the area oflight metal alloys, including Al and/or Mg, in the area of materials processing connected with the entire scopeof problems connected with manufacturing of products and their elements, in the area of the automated lowpressuredie casting, and also in the methodology of structure and properties assessment of the engineeringmaterials with, among others, the X-ray flaw detection and computer image analysis methods.Practical implications: The developed methodology of the automated assessment of quality and properties ofthe light Al and Mg based alloys may be used by manufacturers of subassemblies and elements of engines (e.g.,car engine bodies made from the light alloys with the low-pressure casting in the sand moulds.Originality/value: The project’s effects will be shortening the time needed for analyses and elimination of manusubjective evaluation errors made by humans.

  10. Hybrid Control of a Two-Wheeled Automatic-Balancing Robot with Backlash Feature

    DEFF Research Database (Denmark)

    Løhndorf, Petar Durdevic; Yang, Zhenyu

    2013-01-01

    This paper investigates the application of hybrid control for an automatic balancing robot system subject to backlash effect. The developed controller is a type of sliding mode controller, refereed to as a switching controller, with respect to different situations i.e., whether the backlash is pr...... and comparisons with other solutions show the proposed solution can lead to a very satisfactory anti-backlash performance, with an easy and cost-effective implementation....

  11. Initial design and evaluation of automatic restructurable flight control system concepts

    Science.gov (United States)

    Weiss, J. L.; Looze, D. P.; Eterno, J. S.; Grunberg, D. B.

    1986-01-01

    Results of efforts to develop automatic control design procedures for restructurable aircraft control systems is presented. The restructurable aircraft control problem involves designing a fault tolerance control system which can accommodate a wide variety of unanticipated aircraft failure. Under NASA sponsorship, many of the technologies which make such a system possible were developed and tested. Future work will focus on developing a methodology for integrating these technologies and demonstration of a complete system.

  12. The integrated manual and automatic control of complex flight systems

    Science.gov (United States)

    Schmidt, David K.

    1991-01-01

    Research dealt with the general area of optimal flight control synthesis for manned flight vehicles. The work was generic; no specific vehicle was the focus of study. However, the class of vehicles generally considered were those for which high authority, multivariable control systems might be considered, for the purpose of stabilization and the achievement of optimal handling characteristics. Within this scope, the topics of study included several optimal control synthesis techniques, control-theoretic modeling of the human operator in flight control tasks, and the development of possible handling qualities metrics and/or measures of merit. Basic contributions were made in all these topics, including human operator (pilot) models for multi-loop tasks, optimal output feedback flight control synthesis techniques; experimental validations of the methods developed, and fundamental modeling studies of the air-to-air tracking and flared landing tasks.

  13. Effect of olive oil massage on weight gain in preterm infants: A randomized controlled clinical trial

    Directory of Open Access Journals (Sweden)

    Mahnaz Jabraeile

    2016-01-01

    Full Text Available Background: Despite the fact that effect of massage with or without oil on the baby′s weight gain is not clear, but recent studies have shown that massage with essential oils make lipid absorption through the skin. The aim of this study was to evaluate the effect of olive oil massage on weight gain in preterm infants. Materials and Methods: This study was a single-blind, randomized controlled clinical trial. In this study, infants who met inclusion criteria for the study were divided into two groups by using random numbers table. Newborns in intervention group were under massage for 10 days and 3 times for 15 min daily; the mother of these newborns had been trained already using olive oil. Moreover, the infants of the control group were under massaging without oil same as the above-mentioned method. Researchers weighed babies daily during 10 days and recorded it at the checklist. Data from the study were reviewed and analyzed by descriptive statistics and repeated measure test using the statistical software SPSS/13. Results: This study showed that the neonatal weight gain in the infants with the oil massage was 21 g daily in average, whereas the increase in infant massage without oil was 7 g. This difference was statistically significant (P < 0.001. Conclusion: Considering the positive effect of infant massage on weight gain in premature infants with olive oil, it is recommended that nurses use oil in infant massage in the neonatal units.

  14. Adaptive Clutch Engaging Process Control for Automatic Mechanical Transmission

    Institute of Scientific and Technical Information of China (English)

    LIU Hai-ou; CHEN Hui-yan; DING Hua-rong; HE Zhong-bo

    2005-01-01

    Based on detail analysis of clutch engaging process control targets and adaptive demands, a control strategy which is based on speed signal, different from that of based on main clutch displacement signal, is put forward. It considers both jerk and slipping work which are the most commonly used quality evaluating indexes of vehicle starting phase. The adaptive control system and its reference model are discussed profoundly.Taking the adaptability to different starting gears and different road conditions as examples, some proving field test records are shown to illustrate the main clutch adaptive control strategy at starting phase. Proving field test gives acceptable results.

  15. Improvement of remote control system of automatic ultrasonic equipment for inspection of reactor pressure vessel

    Energy Technology Data Exchange (ETDEWEB)

    Cheong, Yong Moo; Jung, H. K.; Joo, Y. S.; Koo, K. M.; Hyung, H.; Sim, C. M.; Gong, U. S.; Kim, S. H.; Lee, J. P.; Rhoo, H. C.; Kim, M. S.; Ryoo, S. K.; Choi, C. H.; Oh, K. I

    1999-12-01

    One of the important issues related to the nuclear safety is in-service inspection of reactor pressure vessel (RPV). A remote controlled automatic ultrasonic method is applied to the inspection. At present the automatic ultrasonic inspection system owned by KAERI is interrupted due to degradation of parts. In order to resume field inspection new remote control system for the equipment was designed and installed to the existing equipment. New ultrasonic sensors and their modules for RPV inspection were designed and fabricated in accordance with the new requirements of the inspection codes. Ultrasonic sensors were verified for the use in the RPV inspection. (autho0008.

  16. Using Spec Explorer for Automatic Checking of Constraints in Software Controlled Systems.

    Directory of Open Access Journals (Sweden)

    Izzat Mahmoud ALSMADI

    2011-01-01

    Full Text Available In software engineering, several formal models and tools are proposed for defining system requirements and constraints formally. Such formal definitions can help in the automatic checking and verification for them. It can also help in the automatic test case generation, execution and verification. In this paper, we will demonstrate and evaluate the usage of Spec Explorer from Microsoft for defining and checking examples of software controlled system such as cruise control. Such formal requirements can be eventually embedded in the developed system or can help in exposing important elements to test in the testing stage or through the usage of the application

  17. PLC based automatic control of pasteurize mix in ice cream production

    Science.gov (United States)

    Yao, Xudong; Liang, Kai

    2013-03-01

    This paper describes the automatic control device of pasteurized mix in the ice cream production process.We design a scheme of control system using FBD program language and develop the programmer in the STEP 7-Micro/WIN software, check for any bugs before downloading into PLC .These developed devices will able to provide flexibility and accuracy to control the step of pasteurized mix. The operator just Input the duration and temperature of pasteurized mix through control panel. All the steps will finish automatically without any intervention in a preprogrammed sequence stored in programmable logic controller (PLC). With the help of this equipment we not only can control the quality of ice cream for various conditions, but also can simplify the production process. This control system is inexpensive and can be widely used in ice cream production industry.

  18. Design and Implementation of Automatic Air Flow Rate Control System

    Science.gov (United States)

    Akbar, A.; Saputra, C.; Munir, M. M.; Khairurrijal

    2016-08-01

    Venturimeter is an apparatus that can be used to measure the air flow rate. In this experiment we designed a venturimeter which equipped with a valve that is used to control the air flow rate. The difference of pressure between the cross sections was measured with the differential pressure sensor GA 100-015WD which can calculate the difference of pressures from 0 to 3737.33 Pa. A 42M048C Z36 stepper motor was used to control the valve. The precision of this motor rotation is about 0.15 °. A Graphical User Interface (GUI) was developed to monitor and set the value of flow rate then an 8-bit microcontroller was used to process the control system In this experiment- the venturimeter has been examined to get the optimal parameter of controller. The results show that the controller can set the stable output air flow rate.

  19. Testing interactive effects of automatic and conflict control processes during response inhibition - A system neurophysiological study.

    Science.gov (United States)

    Chmielewski, Witold X; Beste, Christian

    2017-02-01

    In everyday life successful acting often requires to inhibit automatic responses that might not be appropriate in the current situation. These response inhibition processes have been shown to become aggravated with increasing automaticity of pre-potent response tendencies. Likewise, it has been shown that inhibitory processes are complicated by a concurrent engagement in additional cognitive control processes (e.g. conflicting monitoring). Therefore, opposing processes (i.e. automaticity and cognitive control) seem to strongly impact response inhibition. However, possible interactive effects of automaticity and cognitive control for the modulation of response inhibition processes have yet not been examined. In the current study we examine this question using a novel experimental paradigm combining a Go/NoGo with a Simon task in a system neurophysiological approach combining EEG recordings with source localization analyses. The results show that response inhibition is less accurate in non-conflicting than in conflicting stimulus-response mappings. Thus it seems that conflicts and the resulting engagement in conflict monitoring processes, as reflected in the N2 amplitude, may foster response inhibition processes. This engagement in conflict monitoring processes leads to an increase in cognitive control, as reflected by an increased activity in the anterior and posterior cingulate areas, while simultaneously the automaticity of response tendencies is decreased. Most importantly, this study suggests that the quality of conflict processes in anterior cingulate areas and especially the resulting interaction of cognitive control and automaticity of pre-potent response tendencies are important factors to consider, when it comes to the modulation of response inhibition processes.

  20. Automatic Control of Contextual Interaction Integrated with Affection and Architectural Attentional Control

    Directory of Open Access Journals (Sweden)

    Yanrong Jiang

    2013-03-01

    Full Text Available It is still a challenge for robots to interact with complex environments in a smooth and natural manner. The robot should be aware of its surroundings and inner status to make decisions accordingly and appropriately. Contexts benefit the interaction a lot, such as avoiding frequent interruptions (e.g., the explicit inputting requests and thus are essential for interaction. Other challenges, such as shifting attentional focus to a more important stimulus, etc., are also crucial in interaction control. This paper presents a hybrid automatic control approach for interaction, as well as its integration, with these multiple important factors, aiming at performing natural, human‐like interactions in robots. In particular, a novel approach of architectural attentional control, based on affection is presented, which attempts to shift the attentional focus in a natural manner. Context‐aware computing is combined with interaction to endow the robot with proactive abilities. The long‐term interaction control approaches are described. Emotion and personality are introduced into the interaction and their influence mechanism on interaction is explored. We implemented the proposal in an interactive head robot (IHR and the experimental results indicate the effectiveness.

  1. Development of Full Automatic Flash Butt Welding with Digital Control

    Institute of Scientific and Technical Information of China (English)

    WANG Rui; SUN Hexu; WANG Hongwen

    2006-01-01

    The hardware and software design of two digital control systems based on 80C196KB MCU for flash butt welder is introduced in this paper. The welding power supply is made of six-phase half-wave rectifier. The welding outer characteristic of welding machine is realized by digital PI algorithm with the voltage close-loop feedback. The flashing curve is finished by electric-hydraulic servo valve .The process control system transfers datum with power supply system by a serial communication interface. The parameters of the control systems are collected by photoelectrical seclusion to avoid the disturbing of the electromagnetism in welding process.

  2. Decentralized PI/PID controllers based on gain and phase margin specifications for TITO processes.

    Science.gov (United States)

    Maghade, D K; Patre, B M

    2012-07-01

    In this paper, a decentralized PI/PID controller design method based on gain and phase margin specifications for two-input-two-output (TITO) interactive processes is proposed. The decouplers are designed for systems to minimize the interaction between the loops, and the first order plus dead time (FOPDT) model is achieved for each decoupled subsystem based on the frequency response fitting. An independent PI/PID controller is designed for each reduced order decoupled subsystem to obtain the desired gain and phase margins, and the performance is verified on the original interactive system to show the effectiveness of the proposed design method for the general class of TITO systems. Simulation examples are incorporated to validate the usefulness of the presented algorithm. An experimentation is performed on the Level-Temperature reactor process to show the practical applicability of the proposed method for the interactive system.

  3. An approach of optimal sensitivity applied in the tertiary loop of the automatic generation control

    Energy Technology Data Exchange (ETDEWEB)

    Belati, Edmarcio A. [CIMATEC - SENAI, Salvador, BA (Brazil); Alves, Dilson A. [Electrical Engineering Department, FEIS, UNESP - Sao Paulo State University (Brazil); da Costa, Geraldo R.M. [Electrical Engineering Department, EESC, USP - Sao Paulo University (Brazil)

    2008-09-15

    This paper proposes an approach of optimal sensitivity applied in the tertiary loop of the automatic generation control. The approach is based on the theorem of non-linear perturbation. From an optimal operation point obtained by an optimal power flow a new optimal operation point is directly determined after a perturbation, i.e., without the necessity of an iterative process. This new optimal operation point satisfies the constraints of the problem for small perturbation in the loads. The participation factors and the voltage set point of the automatic voltage regulators (AVR) of the generators are determined by the technique of optimal sensitivity, considering the effects of the active power losses minimization and the network constraints. The participation factors and voltage set point of the generators are supplied directly to a computational program of dynamic simulation of the automatic generation control, named by power sensitivity mode. Test results are presented to show the good performance of this approach. (author)

  4. 49 CFR 236.401 - Automatic block signal system and interlocking standards applicable to traffic control systems.

    Science.gov (United States)

    2010-10-01

    ... TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Traffic Control Systems Standards § 236.401 Automatic... 49 Transportation 4 2010-10-01 2010-10-01 false Automatic block signal system and interlocking standards applicable to traffic control systems. 236.401 Section 236.401 Transportation Other...

  5. Distributed temperature sensing system using a commercial OTDR and a standard EDFA with controlled gain

    Science.gov (United States)

    Bassan, Fabio R.; Salgado, Felipe C.; Fruett, Fabiano; Rosolem, Joao B.

    2016-05-01

    The distributed temperature sensor system based in the spontaneous Raman backscattering is demonstrated for the first time to our knowledge, using a commercial OTDR (Optical Time Domain Reflectometer) and a standard erbium doped fiber amplifier (EDFA) with controlled gain. We evaluated this approach in a 30 km of single mode fiber using an OTDR pulse width of 100 ns and an EDFA with 17 dBm of output power.

  6. Gain transient control for wavelength division multiplexed access networks using semiconductor optical amplifiers

    DEFF Research Database (Denmark)

    Gibbon, Timothy Braidwood; Osadchiy, Alexey Vladimirovich; Kjær, Rasmus;

    2009-01-01

    measurements how a near-saturated semiconductor optical amplifier (SOA) can be used to control these gain transients. An SOA is shown to reduce the penalty of transients originating in an EDFA from 2.3 dB to 0.2 dB for 10 Gb/s transmission over standard single mode fiber using a 231-1 PRBS pattern. The results...

  7. Research on HCI Prototype Design of Ink Automatic Control System for Offset Printer

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jianyu; GAO Lixin; CUI Lingli; WANG Yingwang; LI Xianghui

    2006-01-01

    In order to solve the low efficiency and poor precision problems of traditional ink control methods on domestic offset printers, developing modern ink automatic control system has become more and more urgent. As an important subsystem, the human computer interface (HCI) is a key function for the wholly automatic control. Once this goal is obtained, all the printing procedures especially the automatic control of ink volume should be finished with human computer interface in different areas. Considering the HCI design theory and structure characteristics of domestic printers comprehensively, the HCI prototype for automatic ink control system has been developed based on Visual Basic platform. As the individual ink key is instead of the integrated key, the division result of ink fountain can be displayed on the interface. Through the interface, the dynamic adjusting functions such as modifying ink volume, locking or unlocking each ink key and real-time displaying the adjusting results etc. can be completed. The simulation test has shown that the opening and practical feature of the prototype is satisfactory.

  8. Carrier-phase differential GPS for automatic control of land vehicles

    Science.gov (United States)

    O'Connor, Michael Lee

    Real-time centimeter-level navigation has countless potential applications in land vehicles, including precise topographic field mapping, runway snowplowing in bad weather, and land mine detection and avoidance. Perhaps the most obvious and immediate need for accurate, robust land vehicle sensing is in the guidance and control of agricultural vehicles. Accurate guidance and automatic control of farm vehicles offers many potential advantages; however, previous attempts to automate these vehicles have been unsuccessful due to sensor limitations. With the recent development of real-time carrier-phase differential GPS (CDGPS), a single inexpensive GPS receiver can measure a vehicle's position to within a few centimeters and orientation to fractions of a degree. This ability to provide accurate real-time measurements of multiple vehicle states makes CDGPS ideal for automatic control of vehicles. This work describes the theoretical and experimental work behind the first successfully demonstrated automatic control system for land vehicles based on CDGPS. An extension of pseudolite-based CDGPS initialization methods was explored for land vehicles and demonstrated experimentally. Original land vehicle dynamic models were developed and identified using this innovative sensor. After initial automatic control testing using a Yamaha Fleetmaster golf cart, a centimeter-level, fully autonomous row guidance capability was demonstrated on a John Deere 7800 farm tractor.

  9. Programmable Logic Controllers for Systems of Automatic of the Level Crossing

    Directory of Open Access Journals (Sweden)

    Mieczyslaw Kornaszewski

    2006-01-01

    Full Text Available The railway crossings are vulnerable to incidence of high number of accidents often deadly. In order to face this problem, the modern systems of automatic of the level crossing have been introduced. These systems are based on Programmable Logic Controllers, which allow the designers to exploit self-control mechanisms, events acquiring, technical diagnostic which in turn enable remote control and acquisition of faults.

  10. Automatic Frequency Controller for Power Amplifiers Used in Bio-Implanted Applications: Issues and Challenges

    Directory of Open Access Journals (Sweden)

    Mahammad A. Hannan

    2014-12-01

    Full Text Available With the development of communication technologies, the use of wireless systems in biomedical implanted devices has become very useful. Bio-implantable devices are electronic devices which are used for treatment and monitoring brain implants, pacemakers, cochlear implants, retinal implants and so on. The inductive coupling link is used to transmit power and data between the primary and secondary sides of the biomedical implanted system, in which efficient power amplifier is very much needed to ensure the best data transmission rates and low power losses. However, the efficiency of the implanted devices depends on the circuit design, controller, load variation, changes of radio frequency coil’s mutual displacement and coupling coefficients. This paper provides a comprehensive survey on various power amplifier classes and their characteristics, efficiency and controller techniques that have been used in bio-implants. The automatic frequency controller used in biomedical implants such as gate drive switching control, closed loop power control, voltage controlled oscillator, capacitor control and microcontroller frequency control have been explained. Most of these techniques keep the resonance frequency stable in transcutaneous power transfer between the external coil and the coil implanted inside the body. Detailed information including carrier frequency, power efficiency, coils displacement, power consumption, supplied voltage and CMOS chip for the controllers techniques are investigated and summarized in the provided tables. From the rigorous review, it is observed that the existing automatic frequency controller technologies are more or less can capable of performing well in the implant devices; however, the systems are still not up to the mark. Accordingly, current challenges and problems of the typical automatic frequency controller techniques for power amplifiers are illustrated, with a brief suggestions and discussion section concerning

  11. Automatic frequency controller for power amplifiers used in bio-implanted applications: issues and challenges.

    Science.gov (United States)

    Hannan, Mahammad A; Hussein, Hussein A; Mutashar, Saad; Samad, Salina A; Hussain, Aini

    2014-12-11

    With the development of communication technologies, the use of wireless systems in biomedical implanted devices has become very useful. Bio-implantable devices are electronic devices which are used for treatment and monitoring brain implants, pacemakers, cochlear implants, retinal implants and so on. The inductive coupling link is used to transmit power and data between the primary and secondary sides of the biomedical implanted system, in which efficient power amplifier is very much needed to ensure the best data transmission rates and low power losses. However, the efficiency of the implanted devices depends on the circuit design, controller, load variation, changes of radio frequency coil's mutual displacement and coupling coefficients. This paper provides a comprehensive survey on various power amplifier classes and their characteristics, efficiency and controller techniques that have been used in bio-implants. The automatic frequency controller used in biomedical implants such as gate drive switching control, closed loop power control, voltage controlled oscillator, capacitor control and microcontroller frequency control have been explained. Most of these techniques keep the resonance frequency stable in transcutaneous power transfer between the external coil and the coil implanted inside the body. Detailed information including carrier frequency, power efficiency, coils displacement, power consumption, supplied voltage and CMOS chip for the controllers techniques are investigated and summarized in the provided tables. From the rigorous review, it is observed that the existing automatic frequency controller technologies are more or less can capable of performing well in the implant devices; however, the systems are still not up to the mark. Accordingly, current challenges and problems of the typical automatic frequency controller techniques for power amplifiers are illustrated, with a brief suggestions and discussion section concerning the progress of

  12. daptive Filter Used as a Dynamic Compensator in Automatic Gauge Control of Strip Rolling Processes

    Directory of Open Access Journals (Sweden)

    N. ROMAN

    2010-12-01

    Full Text Available The paper deals with a control structure of the strip thickness in a rolling mill of quarto type (AGC – Automatic Gauge Control. It performs two functions: the compensation of errors induced by unideal dynamics of the tracking systems lead by AGC system and the control adaptation to the change of dynamic properties of the tracking systems. The compensation of dynamical errors is achieved through inverse models of the tracking system, implemented as adaptive filters.

  13. Automatic Voltage Control (AVC) of Danish Transmission System - Concept design

    DEFF Research Database (Denmark)

    Qin, Nan; Abildgaard, Hans; Lund, P.

    2014-01-01

    , objectives, constraints, algorithms for optimal power flow and some special functions in particular systems, which inspires the concept design of a Danish AVC system to address the future challenges of voltage control. In the concept, the Danish AVC design is based on a centralized control scheme. All...... the buses are monitored where the voltage magnitudes are maintained continually. The loss minimization including switching cost is the objectives of the AVC system. The reactive power reserves as constraints are taken into account to limit the regulation capabilities of generators. The Day ahead and short...

  14. Automatic quadrature control and measuring system. [using optical coupling circuitry

    Science.gov (United States)

    Hamlet, J. F. (Inventor)

    1974-01-01

    A quadrature component cancellation and measuring system comprising a detection system for detecting the quadrature component from a primary signal, including reference circuitry to define the phase of the quadrature component for detection is described. A Raysistor optical coupling control device connects an output from the detection system to a circuit driven by a signal based upon the primary signal. Combining circuitry connects the primary signal and the circuit controlled by the Raysistor device to subtract quadrature components. A known current through the optically sensitive element produces a signal defining the magnitude of the quadrature component.

  15. Application of the concept of dynamic trim control to automatic landing of carrier aircraft. [utilizing digital feedforeward control

    Science.gov (United States)

    Smith, G. A.; Meyer, G.

    1980-01-01

    The results of a simulation study of an alternative design concept for an automatic landing control system are presented. The alternative design concept for an automatic landing control system is described. The design concept is the total aircraft flight control system (TAFCOS). TAFCOS is an open loop, feed forward system that commands the proper instantaneous thrust, angle of attack, and roll angle to achieve the forces required to follow the desired trajector. These dynamic trim conditions are determined by an inversion of the aircraft nonlinear force characteristics. The concept was applied to an A-7E aircraft approaching an aircraft carrier. The implementation details with an airborne digital computer are discussed. The automatic carrier landing situation is described. The simulation results are presented for a carrier approach with atmospheric disturbances, an approach with no disturbances, and for tailwind and headwind gusts.

  16. Analysis of Information Systems Based on Automatic Control Theory,

    Science.gov (United States)

    The development of information systems in the USSR have given rise to increased interest in studing them. In this report basic attention is given...to the problems of optimizing the operation and control of information systems . It appears that this problem can be solved most fruitfully on the basis

  17. Automatic phase control in solar power satellite systems

    Science.gov (United States)

    Lindsey, W. C.; Kantak, A. V.

    1978-01-01

    Various approaches to the problem of generating, maintaining and distributing a coherent, reference phase signal over a large area are suggested, mathematically modeled and analyzed with respect to their ability to minimize: phase build-up, beam diffusion and beam steering phase jitter, cable length, and maximize power transfer efficiency. In addition, phase control configurations are suggested which alleviate the need for layout symmetry.

  18. Preventing Weight Gain in Women in Rural Communities: A Cluster Randomised Controlled Trial.

    Directory of Open Access Journals (Sweden)

    Catherine Lombard

    2016-01-01

    Full Text Available Obesity is reaching epidemic proportions in both developed and developing countries. Even modest weight gain increases the risk for chronic illness, yet evidence-based interventions to prevent weight gain are rare. This trial will determine if a simple low-intensity intervention can prevent weight gain in women compared to general health information.We conducted a 1-yr pragmatic, cluster randomised controlled trial in 41 Australian towns (clusters randomised using a computer-generated randomisation list for intervention (n = 21 or control (n = 20. Women aged 18 to 50 yr were recruited from the general population to receive a 1-yr self-management lifestyle intervention (HeLP-her consisting of one group session, monthly SMS text messages, one phone coaching session, and a program manual, or to a control group receiving one general women's health education session. From October 2012 to April 2014 we studied 649 women, mean age 39.6 yr (+/- SD 6.7 and BMI of 28.8 kg/m(2 (+/- SD 6.9 with the primary outcome weight change between groups at 1 yr. The mean change in the control was +0.44 kg (95% CI -0.09 to 0.97 and in the intervention group -0.48 kg (95% CI -0.99 to 0.03 with an unadjusted between group difference of -0.92 kg (95% CI -1.67 to -0.16 or -0.87 kg (95% CI -1.62 to -0.13 adjusted for baseline values and clustering. Secondary outcomes included improved diet quality and greater self-management behaviours. The intervention appeared to be equally efficacious across all age, BMI, income, and education subgroups. Loss to follow-up included 23.8% in the intervention group and 21.8% in the control group and was within the anticipated range. Limitations include lack of sensitive tools to measure the small changes to energy intake and physical activity. Those who gained weight may have been less inclined to return for 1 yr weight measures.A low intensity lifestyle program can prevent the persistent weight gain observed in women. Key features included

  19. Robust Model Predictive Control of a Nonlinear System with Known Scheduling Variable and Uncertain Gain

    DEFF Research Database (Denmark)

    Mirzaei, Mahmood; Poulsen, Niels Kjølstad; Niemann, Hans Henrik

    2012-01-01

    Robust model predictive control (RMPC) of a class of nonlinear systems is considered in this paper. We will use Linear Parameter Varying (LPV) model of the nonlinear system. By taking the advantage of having future values of the scheduling variable, we will simplify state prediction. Because...... of the special structure of the problem, uncertainty is only in the B matrix (gain) of the state space model. Therefore by taking advantage of this structure, we formulate a tractable minimax optimization problem to solve robust model predictive control problem. Wind turbine is chosen as the case study and we...

  20. New Gain Controllable Resistor-less Current-mode First Order Allpass Filter and its Application

    Directory of Open Access Journals (Sweden)

    W. Jaikla

    2012-04-01

    Full Text Available New first order allpass filter (APF in current mode, constructed from 2 CCCCTAs and grounded capacitor, is presented. The current gain and phase shift can be electronically /orthogonally controlled. Low input and high output impedances are achieved which make the circuit to be easily cascaded to the current-mode circuit without additional current buffers. The operation of the proposed filter has been verified through simulation results which confirm the theoretical analysis. The application example as current-mode quadrature oscillator with non-interactive current control for both of oscillation condition and oscillation frequency is included to show the usability of the proposed filter.

  1. Extremum-seeking with variable gain control for intensifying biogas production in anaerobic fermentation.

    Science.gov (United States)

    Liu, J; Olsson, G; Mattiasson, B

    2006-01-01

    A state-dependent variable-gain control system is implemented to follow the characteristics of a laboratory-scale up-flow anaerobic fixed-bed reactor dynamically. The transition from one state to another is determined on an hourly basis, depending on difference between the setpoint of the reactor pH and its true value. Considerable improvement of the process stability--reduction of oscillation in both the reactor pH and biogas production rate during high-rate operation, has been achieved, although the control structure is simple and intuitive.

  2. Automatic quality control in the production of ceramic substrates by pulsed laser cutting

    DEFF Research Database (Denmark)

    Morace, Renate Erica; Hansen, Hans Nørgaard; De Chiffre, Leonardo

    2004-01-01

    This paper deals with the use of optical coordinate measuring machines (CMMs) in the quality control of ceramic substrates produced by a CO2 pulsed laser. A procedure of automatic measurements on a CMM equipped with a CCD camera was developed. In particular, the number and the distribution...

  3. 76 FR 79754 - Twelfth Meeting: RTCA Special Committee 220, Automatic Flight Guidance and Control

    Science.gov (United States)

    2011-12-22

    ... Federal Aviation Administration Twelfth Meeting: RTCA Special Committee 220, Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), U.S. Department of Transportation (DOT). ACTION... Return to general plenary meeting Review of WG 2 status--progress, issues and plan Review of WG 3...

  4. 76 FR 50809 - Eleventh Meeting: RTCA Special Committee 220: Automatic Flight Guidance and Control

    Science.gov (United States)

    2011-08-16

    ... Federal Aviation Administration Eleventh Meeting: RTCA Special Committee 220: Automatic Flight Guidance and Control AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Correction of Notice of RTCA... plenary meeting RTCA paper no. 011-11/SC220-024 Presentation of progress of Working Group-2...

  5. Using Automatic Code Generation in the Attitude Control Flight Software Engineering Process

    Science.gov (United States)

    McComas, David; O'Donnell, James R., Jr.; Andrews, Stephen F.

    1999-01-01

    This paper presents an overview of the attitude control subsystem flight software development process, identifies how the process has changed due to automatic code generation, analyzes each software development phase in detail, and concludes with a summary of our lessons learned.

  6. Postural Control and Automaticity in Dyslexic Children: The Relationship between Visual Information and Body Sway

    Science.gov (United States)

    Barela, Jose A.; Dias, Josenaldo L.; Godoi, Daniela; Viana, Andre R.; de Freitas, Paulo B.

    2011-01-01

    Difficulty with literacy acquisition is only one of the symptoms of developmental dyslexia. Dyslexic children also show poor motor coordination and postural control. Those problems could be associated with automaticity, i.e., difficulty in performing a task without dispending a fair amount of conscious efforts. If this is the case, dyslexic…

  7. Adaptive Automatic Gauge Control of a Cold Strip Rolling Process

    Directory of Open Access Journals (Sweden)

    ROMAN, N.

    2010-02-01

    Full Text Available The paper tackles with thickness control structure of the cold rolled strips. This structure is based on the rolls position control of a reversible quarto rolling mill. The main feature of the system proposed in the paper consists in the compensation of the errors introduced by the deficient dynamics of the hydraulic servo-system used for the rolls positioning, by means of a dynamic compensator that approximates the inverse system of the servo-system. Because the servo-system is considered variant over time, an on-line identification of the servo-system and parameter adapting of the compensator are achieved. The results obtained by numerical simulation are presented together with the data taken from real process. These results illustrate the efficiency of the proposed solutions.

  8. Iron ore sintering. Part 3: Automatic and control systems

    Directory of Open Access Journals (Sweden)

    Alejandro Cores

    2015-01-01

    Full Text Available El proceso de sinterización implica un gran número de parámetros, más de quinientos, cada uno de los cuales ejerce una mayor o menor influencia y necesita ser controlado, dentro de los límites posibles, con el fin de optimizar la productividad, la estabilidad del proceso, y la composición y la calidad de la sinterizado producido. Para cumplir con la legislación ambiental, un sistema de control de la contaminación debe monitorizar la composición de las partículas y los gases generados en la planta de sinterización y emitidos a la atmósfera. Los sistemas de automatización y control son herramientas vitales para ayudar a los operadores de la planta en el seguimiento de cada etapa del proceso de producción de sinterizado.

  9. A novel analog power supply for gain control of the Multi-Pixel Photon Counter (MPPC)

    Science.gov (United States)

    Li, Zhengwei; Liu, Congzhan; Xu, Yupeng; Yan, Bo; Li, Yanguo; Lu, Xuefeng; Li, Xufang; Zhang, Shuo; Chang, Zhi; Li, Jicheng; Gao, He; Zhang, Yifei; Zhao, Jianling

    2017-04-01

    Silicon Photo-Multipliers (SiPM) are regarded as novel photo-detectors to replace conventional Photo-Multiplier Tubes (PMTs). However, the breakdown voltage dependence on the ambient temperature results in a gain variation of ∼3%/°C. This severely limits the application of this device in experiments with wide range of operating temperature, especially in space missions. An experimental setup was established to investigate the temperature and bias voltage dependence of gain for the Multi-Pixel Photon Counter (MPPC). The gain and breakdown voltage dependence on operating temperature of an MPPC can be approximated by a linear function, which is similar to the behavior of a zener diode. The measured temperature coefficient of the breakdown voltage is (59.4±0.4 mV)/°C. According to this fact, an analog power supply based on two zener diodes and an operational amplifier was designed with a positive temperature coefficient. The measured temperature dependence for the designed power supply is between 63.65-64.61 mV/°C at different output voltages. The designed power supply can bias the MPPC at an over-voltage with a temperature variation of ∼5 mV/°C. The gain variation of the MPPC biased at over-voltage of 2 V was reduced from 2.8 % / ° C to 0.3 % / ° C when biased the MPPC with the designed power supply for gain control. Detailed design and performance of the analog power supply in the temperature range from - 42.7 ° C to 20.9 ° C will be discussed in this paper.

  10. Distributed adaptive output consensus control of second-order systems containing unknown non-linear control gains

    Science.gov (United States)

    Wang, Gang; Wang, Chaoli; Du, Qinghui; Cai, Xuan

    2016-10-01

    In this paper, we address the output consensus problem of tracking a desired trajectory for a group of second-order agents on a directed graph with a fixed topology. Each agent is modelled by a second-order non-linear system with unknown non-linear dynamics and unknown non-linear control gains. Only a subset of the agents is given access to the desired trajectory information directly. A distributed adaptive consensus protocol driving all agents to track the desired trajectory is presented using the backstepping technique and approximation technique of Fourier series (FSs). The FS structure is taken not only for tracking the non-linear dynamics but also the unknown portion in the controller design procedure, which can avoid virtual controllers containing the uncertain terms. Stability analysis and parameter convergence of the proposed algorithm are conducted based on the Lyapunov theory and the algebraic graph theory. It is also demonstrated that arbitrary small tracking errors can be achieved by appropriately choosing design parameters. Though the proposed work is applicable for second-order non-linear systems containing unknown non-linear control gains, the proposed controller design can be easily extended to higher-order non-linear systems containing unknown non-linear control gains. Simulation results show the effectiveness of the proposed schemes.

  11. Design of Constant Gain Dissipative Controllers for Eigensystem Assignment in Passive Systems

    Science.gov (United States)

    Maghami, Peiman G.; Gupta, Sandeep

    1998-01-01

    Partial eigensystem assignment with output feedback can lead to an unstable closed-loop system. However, output feedback with passive linear time-invariant systems, such as flexible space structures, is guaranteed to be stable if the controller is dissipative. This paper presents a novel approach for synthesis of dissipative output feedback gain matrices for assigning a selected number of closed-loop poles. Dissipativity of a gain matrix is known to be equivalent to positive semidefiniteness of the symmetric part of the matrix. A sequential procedure is presented to assign one self-conjugate pair of closed-loop eigenvalues at each step using dissipative output feedback gain matrices, while ensuring that the eigenvalues assigned in the previous steps are not disturbed. The problem of assigning one closed-loop pair is reduced to a constrained solution of a system of quadratic equations, and necessary and sufficient conditions for the existence of a solution are presented. A minimax approach is presented for determining parameters which satisfy these conditions. This method can assign as many closed-loop system poles as the number of control inputs. A numerical example of damping enhancement for a flexible structure is presented to demonstrate the approach.

  12. WGC Based Robust and Gain Scheduling PI Controller Design for Condensing Boilers

    Directory of Open Access Journals (Sweden)

    Cem Onat

    2014-05-01

    Full Text Available This paper addresses the water temperature PI control in condensing domestic boilers. The main challenge of this process under the controller design perspective is the fact that the dynamics of condensing boilers are strongly affected by the demanded water flow rate. First, a robust PI controller based on weighted geometrical center method is designed that stabilizes and achieves good performance for closed-loop system for a wide range of the water flow rate. Then, it is shown that if the water flow rate information is used to update the controller gains, through a technique known as gain scheduled control, the performance can be significantly improved. Important characteristics of these PI design approaches are that the resulting parameters are calculated numerically without using any graphical method or iterative optimization process and that it guarantees the stability of the closed-loop. Significantly, simulation results have demonstrated that the proposed tuning techniques can perform better for set point changes and load disturbance than other available methods in the literature.

  13. Determinants of rapid weight gain during infancy: baseline results from the NOURISH randomised controlled trial

    Directory of Open Access Journals (Sweden)

    Mihrshahi Seema

    2011-11-01

    Full Text Available Abstract Background Rapid weight gain in infancy is an important predictor of obesity in later childhood. Our aim was to determine which modifiable variables are associated with rapid weight gain in early life. Methods Subjects were healthy infants enrolled in NOURISH, a randomised, controlled trial evaluating an intervention to promote positive early feeding practices. This analysis used the birth and baseline data for NOURISH. Birthweight was collected from hospital records and infants were also weighed at baseline assessment when they were aged 4-7 months and before randomisation. Infant feeding practices and demographic variables were collected from the mother using a self administered questionnaire. Rapid weight gain was defined as an increase in weight-for-age Z-score (using WHO standards above 0.67 SD from birth to baseline assessment, which is interpreted clinically as crossing centile lines on a growth chart. Variables associated with rapid weight gain were evaluated using a multivariable logistic regression model. Results Complete data were available for 612 infants (88% of the total sample recruited with a mean (SD age of 4.3 (1.0 months at baseline assessment. After adjusting for mother's age, smoking in pregnancy, BMI, and education and infant birthweight, age, gender and introduction of solid foods, the only two modifiable factors associated with rapid weight gain to attain statistical significance were formula feeding [OR = 1.72 (95%CI 1.01-2.94, P = 0.047] and feeding on schedule [OR = 2.29 (95%CI 1.14-4.61, P = 0.020]. Male gender and lower birthweight were non-modifiable factors associated with rapid weight gain. Conclusions This analysis supports the contention that there is an association between formula feeding, feeding to schedule and weight gain in the first months of life. Mechanisms may include the actual content of formula milk (e.g. higher protein intake or differences in feeding styles, such as feeding to schedule

  14. Optimization of Automatic Train Control for Energy Management and Service Reliability

    Energy Technology Data Exchange (ETDEWEB)

    Susanna P. Gordon; Richard M. Wheeler; Timothy J. Sa; Donald A. Sheaffer

    1999-11-01

    A new generation of automatic train control systems is currently under development in the commuter-rail transit industry. These systems will utilize radio communication between wayside control computers and trains in order to provide high precision train control beyond the capability of today's automatic systems. The Bay Area Rapid Transit (BART) system is developing such a modern control system in collaboration with Harmon Industries. This system, called the Advanced Automatic Train Control (AATC) system, will allow for precision train locating and control, and will facilitate coordination of the trajectories of multiple trains. This system will be capable of running trains more closely together and decreasing the time a train requires to traverse the system, while simultaneously operating with a more modest traction power infrastructure, and providing a smoother, more comfortable ride to commuters. The authors have collaborated with BART to develop a simulator of the AATC system and the traction power system, and they have utilized this simulator as a testbed for the development of advanced train control techniques. Several train control algorithms, including one employing a neural network for train voltage prediction, have been developed and tested in the simulator. Smoother train trajectories, reduced power infrastructure requirements, and reduced energy consumption have been demonstrated. Improved service reliability is also expected to result.

  15. An automatically controlled predistorter for multilevel quadrature amplitude modulation

    Science.gov (United States)

    Namiki, J.

    1983-05-01

    In digital microwave transmission, the nonlinear characteristics in a high power amplifier, such as a TWT (traveling-wave tube), inhibit efficient output use. This note introduces a new predistorter control technique, and assesses the nonlinear compensation capability of a third-order predistorter incorporating this technique. Concerning 16-QAM (quadrature amplitude modulation), a 10 dB reduction in out-of-band emission and larger than 8 dB C/N improvement with respect to symbol error rate can be achieved at 3 dB TWT average output power backoff.

  16. A small-gain method for integrated guidance and control in terminal phase of reentry

    Science.gov (United States)

    Yan, Han; Tan, Shuping; He, Yingzi

    2017-03-01

    The guidance and control systems of reentry vehicles are usually designed separately and then integrated, but the scheme can be argued that synergistic relationships between the two subsystems are not fully exploited. In order to improve the performance of reusable launch vehicles (RLVs), this paper proposes an integrated guidance and control law for approach and landing of a RLV. According to the idea of reference-trajectory guidance, the angle of attack and bank angle commands are designed using sliding mode control (SMC) method to make the reference-trajectory tacking error converge into a small neighborhood of zero. An integrated guidance and control (IGC) law is developed utilizing generalized small-gain theorem to enforce the commands, and theoretical analysis shows that the law can guarantee the stability of the overall system. The Monte Carlo simulation confirms the effectiveness of the proposed design approach.

  17. Unattended vehicle detection for automatic traffic light control

    Science.gov (United States)

    Abdel Hady, Aya Salama; Moustafa, Mohamed

    2013-12-01

    Machine vision based traffic light control depends mainly on measuring traffic statistics at cross roads. Most of the previous studies have not taken unattended vehicles into consideration when calculating either the traffic density or the traffic flow. In this paper, we propose incorporating unattended vehicles into a new metric for measuring the traffic congestion. In addition to the vehicle motion analysis, opening the driver's side door is an important indicator that this vehicle is going to be unattended. Therefore, we focus in this paper on presenting how to detect this event for stationary vehicles from a live camera or a video feed. Through a set of experiments, we have found out that a Scale Invariant Feature Transform (SIFT) feature-descriptor with a Support Vector Machines (SVM) classifier was able to successfully classify open-door vehicles from closed-door ones in 96.7% of our test dataset.

  18. Study of an automatic trajectory following control system

    Science.gov (United States)

    Vanlandingham, H. F.; Moose, R. L.; Zwicke, P. E.; Lucas, W. H.; Brinkley, J. D.

    1983-01-01

    It is shown that the estimator part of the Modified Partitioned Adaptive Controller, (MPAC) developed for nonlinear aircraft dynamics of a small jet transport can adapt to sensor failures. In addition, an investigation is made into the potential usefulness of the configuration detection technique used in the MPAC and the failure detection filter is developed that determines how a noise plant output is associated with a line or plane characteristic of a failure. It is shown by computer simulation that the estimator part and the configuration detection part of the MPAC can readily adapt to actuator and sensor failures and that the failure detection filter technique cannot detect actuator or sensor failures accurately for this type of system because of the plant modeling errors. In addition, it is shown that the decision technique, developed for the failure detection filter, can accurately determine that the plant output is related to the characteristic line or plane in the presence of sensor noise.

  19. Short communication: Automatic washing of hooves can help control digital dermatitis in dairy cows.

    Science.gov (United States)

    Thomsen, Peter T; Ersbøll, Annette Kjær; Sørensen, Jan Tind

    2012-12-01

    The objectives of this study were to develop and test a system for automatic washing of the hooves of dairy cows and to evaluate the effect of frequent automatic washing on the prevalence of digital dermatitis (DD). An automatic hoof washer was developed in an experimental dairy herd and tested in 6 commercial dairy herds in 2 experiments (1 and 2). In the experimental herd, automatic hoof washing resulted in cleaner hooves. In experiments 1 and 2, cows were washed after each milking on the left side only, leaving the right side unwashed as a within-cow control. In experiment 1, hooves were washed with a water and 0.4% soap solution. In experiment 2, hooves were washed with water only. In each experiment, DD was scored in a hoof-trimming chute approximately 60 d after the start of hoof washing. Data were analyzed using a generalized linear mixed model. The outcome was the DD status of each leg (DD positive or DD negative). Herd and cow within herd were included as random effects, and treatment (washing or control) was included as a fixed effect. The statistical analyses showed that the odds ratio of having DD was 1.48 in the control leg compared with the washed leg in experiment 1. In experiment 2, the odds ratio of having DD was 1.27 in the control leg compared with the washed leg. We concluded that automatic washing of hooves with water and soap can help decrease the prevalence of DD in commercial dairy herds.

  20. Automatic computation of conservation laws in the calculus of variations and optimal control

    OpenAIRE

    2006-01-01

    Computer Application We present analytic computational tools that permit us to identify, in an automatic way, conservation laws in optimal control. The central result we use is the famous Noether's theorem, a classical theory developed by Emmy Noether in 1918, in the context of the calculus of variations and mathematical physics, and which was extended recently to the more general context of optimal control. We show how a Computer Algebra System can be very helpful in finding the symmetrie...

  1. The application of charge-coupled device processors in automatic-control systems

    Science.gov (United States)

    Mcvey, E. S.; Parrish, E. A., Jr.

    1977-01-01

    The application of charge-coupled device (CCD) processors to automatic-control systems is suggested. CCD processors are a new form of semiconductor component with the unique ability to process sampled signals on an analog basis. Specific implementations of controllers are suggested for linear time-invariant, time-varying, and nonlinear systems. Typical processing time should be only a few microseconds. This form of technology may become competitive with microprocessors and minicomputers in addition to supplementing them.

  2. Application of NASA-developed technology to the automatic control of municipal sewage treatment plants

    Science.gov (United States)

    Hiser, L. L.; Herrera, W. R.

    1973-01-01

    A search was made of NASA developed technology and commercial technology for process control sensors and instrumentation which would be applicable to the operation of municipal sewage treatment plants. Several notable items were found from which process control concepts were formulated that incorporated these items into systems to automatically operate municipal sewage treatment plants. A preliminary design of the most promising concept was developed into a process control scheme for an activated sludge treatment plant. This design included process control mechanisms for maintaining constant food to sludge mass (F/M) ratio, and for such unit processes as primary sedimentation, sludge wastage, and underflow control from the final clarifier.

  3. Redesign of a Variable-Gain Output Feedback Longitudinal Controller Flown on the High-Alpha Research Vehicle (HARV)

    Science.gov (United States)

    Ostroff, Aaron J.

    1998-01-01

    This paper describes a redesigned longitudinal controller that flew on the High-Alpha Research Vehicle (HARV) during calendar years (CY) 1995 and 1996. Linear models are developed for both the modified controller and a baseline controller that was flown in CY 1994. The modified controller was developed with three gain sets for flight evaluation, and several linear analysis results are shown comparing the gain sets. A Neal-Smith flying qualities analysis shows that performance for the low- and medium-gain sets is near the level 1 boundary, depending upon the bandwidth assumed, whereas the high-gain set indicates a sensitivity problem. A newly developed high-alpha Bode envelope criterion indicates that the control system gains may be slightly high, even for the low-gain set. A large motion-base simulator in the United Kingdom was used to evaluate the various controllers. Desired performance, which appeared to be satisfactory for flight, was generally met with both the low- and medium-gain sets. Both the high-gain set and the baseline controller were very sensitive, and it was easy to generate pilot-induced oscillation (PIO) in some of the target-tracking maneuvers. Flight target-tracking results varied from level 1 to level 3 and from no sensitivity to PIO. These results were related to pilot technique and whether actuator rate saturation was encountered.

  4. Voluntary Fasting to Control Post-Ramadan Weight Gain among Overweight and Obese Women

    Directory of Open Access Journals (Sweden)

    Suriani Ismail

    2015-01-01

    Full Text Available Objectives: This study aimed to examine the effectiveness of an Islamic voluntary fasting intervention to control post-Ramadan weight gain. Methods: This study was conducted between July and November 2011. Two weight loss intervention programmes were developed and implemented among groups of overweight or obese Malay women living in the Malaysian cities of Putrajaya and Seremban: a standard programme promoting control of food intake according to national dietary guidelines (group B and a faith-based programme promoting voluntary fasting in addition to the standard programme (group A. Participants’ dietary practices (i.e., voluntary fasting practices, frequency of fruit/vegetable consumption per week and quantity of carbohydrates/protein consumed per day, body mass index (BMI, blood pressure, fasting blood high-density lipoprotein cholesterol (HDL-C and total cholesterol (TC:HDL-C ratio were assessed before Ramadan and three months post-Ramadan. Results: Voluntary fasting practices increased only in group A (P <0.01. Additionally, the quantity of protein/carbohydrates consumed per day, mean diastolic pressure and TC:HDL-C ratio decreased only in group A (P <0.01, 0.05, 0.02 and <0.01, respectively. Frequency of fruit/vegetable consumption per week, as well as HDL-C levels, increased only in group A (P = 0.03 and <0.01, respectively. Although changes in BMI between the groups was not significant (P = 0.08, BMI decrease among participants in group A was significant (P <0.01. Conclusion: Control of post-Ramadan weight gain was more evident in the faith-based intervention group. Healthcare providers should consider faith-based interventions to encourage weight loss during Ramadan and to prevent post-Ramadan weight gain among patients.

  5. Gain tuning PI controllers for boiler turbine unit using a new hybrid jump PSO

    Directory of Open Access Journals (Sweden)

    Mohamed Sayed

    2015-05-01

    Full Text Available In this paper, a new hybrid jump PSO (HJPSO is proposed for tuning the gains of PI controllers to the boiler turbine unit. HJPSO based Gaussian and Cauchy mutation is proposed to improve the standard PSO performance. The new strategy is based on observing the local and global best particles which are not improved in a predefined number of iterations and moving these particles to a new best position. Besides, forming a new particle that handles the minimum error of each controller to replace the global best particle if it has best fitness. The simulation results show that the proposed algorithm has its ability in optimizing the control parameters and effectively achieved better performance when compared with other PSO algorithms.

  6. Intelligent Control of Diesel Generators Using Gain-Scheduling Based on Online External-Load Estimation

    DEFF Research Database (Denmark)

    Mai, Christian; Jepsen, Kasper Lund; Yang, Zhenyu;

    2014-01-01

    keep a consistent performance for a wide range of operating conditions. Technically, a general nonlinear dynamic model is firstly developed based on fundamental principles of diesel generators. Then, the system parameters of this model can be identified experimentally or partially retrieved from...... the data-sheet for a specific unit. By combining an online external-load estimation with this specific units model, finally an intelligent control using the online gain scheduling strategy is proposed. The proposed solution is verified and analyzed based on a lab-sized emulator of a diesel generator, where...... a controlled AC-motor is employed to emulate a diesel engine. The testing results clearly show that the proposed control solution can lead to a better overall system performance than most existing solutions do, especially subject to widely diverse operating conditions....

  7. Stability of Gain Scheduling Control for Aircraft with Highly Nonlinear Behavior

    Directory of Open Access Journals (Sweden)

    Fany Mendez-Vergara

    2014-01-01

    Full Text Available The main goal of this work is to study the stability properties of an aircraft with nonlinear behavior, controlled using a gain scheduled approach. An output feedback is proposed which is able to guarantee asymptotical stability of the task-coordinates origin and safety of the operation in the entire flight envelope. The results are derived using theory of hybrid and singular perturbed systems. It is demonstrated that both body velocity and orientation asymptotic tracking can be obtained in spite of nonlinearities and uncertainty. The results are illustrated using numerical simulations in F16 jet.

  8. Inhibitory motor control in old age: evidence for de-automatization?

    Science.gov (United States)

    Maylor, Elizabeth Ann; Birak, Kulbir Singh; Schlaghecken, Friederike

    2011-01-01

    To examine age-related effects on high-level consciously controlled and low-level automatically controlled inhibitory processes, the Simon task was combined with the masked prime task in a hybrid procedure. Young and older adults responded to the identity of targets (left/right key-press to left-/right-pointing arrows) that appeared on the left/right of the screen and were preceded by left-/right-pointing backward-masked arrow primes at fixation. Responses were faster and more accurate when the target was congruent with its location than incongruent (Simon effect), and when the target was incompatible with the prime than compatible (negative compatibility effect; NCE). The Simon effect was disproportionately larger, and the NCE disproportionately delayed, in older adults compared to young adults, indicating both high- and low-level inhibitory control deficits with aging. Moreover, the two effects were additive in young adults, but interactive in older adults, providing support for the dedifferentiation hypothesis of aging. Specifically, older adults' prime-related inhibitory control appeared improved on incongruent relative to congruent trials, suggesting that impaired automatic control was substituted by high-level, non-automatic processes.

  9. Inhibitory motor control in old age: evidence for de-automatization?

    Directory of Open Access Journals (Sweden)

    Elizabeth Ann Maylor

    2011-06-01

    Full Text Available To examine age-related effects on high-level consciously-controlled and low-level automatically-controlled inhibitory processes, the Simon task was combined with the masked prime task in a hybrid procedure. Young and older adults responded to the identity of targets (left/right key-press to left-/right-pointing arrows that appeared on the left/right of the screen and were preceded by left-/right-pointing backward-masked arrow primes at fixation. Responses were faster and more accurate when the target was congruent with its location than incongruent (Simon effect, and when the target was incompatible with the prime than compatible (negative compatibility effect; NCE. The Simon effect was disproportionately larger, and the NCE disproportionately delayed, in older adults compared to young adults, indicating both high- and low-level inhibitory control deficits with aging. Moreover, the two effects were additive in young adults, but interactive in older adults, providing support for the dedifferentiation hypothesis of aging. Specifically, older adults’ prime-related inhibitory control appeared improved on incongruent relative to congruent trials, suggesting that impaired automatic control was substituted by high-level, non-automatic processes.

  10. Feedback shape control for deployable mesh reflectors using gain scheduling method

    Science.gov (United States)

    Xie, Yangmin; Shi, Hang; Alleyne, Andrew; Yang, Bingen

    2016-04-01

    This paper presents a theoretical study on the dynamic shape control problem of deployable mesh reflectors (DMRs) via feedback approaches. The reflector structure is simplified from a nonlinear model to be quasi-static with respect to temperature variations but dynamic with respect to mechanical vibrations. The orbital cycle is segmented into multiple temperature zones, and an H∞ robust state feedback controller is designed for each zone to guarantee the local stability of the system under the model uncertainty caused by thermal effects and to reject external force disturbances. At the same time, gain scheduling control method is adopted to compensate thermal distortions and to ensure smooth transition response when switching among the local robust controllers. A DMR model is considered in the case study to show the effectiveness of the control approach. The structural vibrations caused by external force disturbances can be sufficiently suppressed in a much shorter time. The closed loop response of the DMR structure shows that much higher surface accuracy is obtained during the orbiting mission compared to the open-loop configuration, and transient focal length and transient de-focus of the reflector are well controlled within the satisfactory bounds, demonstrating the numerical feasibility of the proposed method to solve the dynamic shape control problem of DMRs.

  11. Automatic Gauge Control in Rolling Process Based on Multiple Smith Predictor Models

    Directory of Open Access Journals (Sweden)

    Jiangyun Li

    2014-01-01

    Full Text Available Automatic rolling process is a high-speed system which always requires high-speed control and communication capabilities. Meanwhile, it is also a typical complex electromechanical system; distributed control has become the mainstream of computer control system for rolling mill. Generally, the control system adopts the 2-level control structure—basic automation (Level 1 and process control (Level 2—to achieve the automatic gauge control. In Level 1, there is always a certain distance between the roll gap of each stand and the thickness testing point, leading to the time delay of gauge control. Smith predictor is a method to cope with time-delay system, but the practical feedback control based on traditional Smith predictor cannot get the ideal control result, because the time delay is hard to be measured precisely and in some situations it may vary in a certain range. In this paper, based on adaptive Smith predictor, we employ multiple models to cover the uncertainties of time delay. The optimal model will be selected by the proposed switch mechanism. Simulations show that the proposed multiple Smith model method exhibits excellent performance in improving the control result even for system with jumping time delay.

  12. Bond graph modeling, simulation, and reflex control of the Mars planetary automatic vehicle

    Science.gov (United States)

    Amara, Maher; Friconneau, Jean Pierre; Micaelli, Alain

    1993-01-01

    The bond graph modeling, simulation, and reflex control study of the Planetary Automatic Vehicle are considered. A simulator derived from a complete bond graph model of the vehicle is presented. This model includes both knowledge and representation models of the mechanical structure, the floor contact, and the Mars site. The MACSYMEN (French acronym for aided design method of multi-energetic systems) is used and applied to study the input-output power transfers. The reflex control is then considered. Controller architecture and locomotion specificity are described. A numerical stage highlights some interesting results of the robot and the controller capabilities.

  13. Adjustment of automatic control systems of production facilities at coal processing plants using multivariant physico- mathematical models

    Science.gov (United States)

    Evtushenko, V. F.; Myshlyaev, L. P.; Makarov, G. V.; Ivushkin, K. A.; Burkova, E. V.

    2016-10-01

    The structure of multi-variant physical and mathematical models of control system is offered as well as its application for adjustment of automatic control system (ACS) of production facilities on the example of coal processing plant.

  14. Coherence-controlled transparency and far-from-degenerate parametric gain in a strongly-absorbing Doppler-broadened medium

    CERN Document Server

    George, T F; George, Thomas F.

    2000-01-01

    An inversionless gain of anti-Stokes radiation above the oscillation threshold in an optically-dense far-from-degenerate double-Lambda Doppler-broadened medium accompanied by Stokes gain is predicted. The outcomes are illustrated with numerical simulations applied to sodium dimer vapor. Optical switching from absorption to gain via transparency controlled by a small variation of the medium and of the driving radiation parameters which are at a level less than one photon per molecule is shown.

  15. The Analysis of Some Methods Less Ordinary Concerning the Assessment of the Controllability of the Automatic Systems

    Directory of Open Access Journals (Sweden)

    Mircea Negrău

    2008-05-01

    Full Text Available In many situations it has to be pointed out if an automatic system is controllable and in what controllability type it is integrated. Because the complete controllability represents the best situation, in the present study we are going to deal with it. From the multiple ways mentioned in the literature of defining and analyzing the property of complete controllability of automatic systems, we introduce some ordinate equivalent formulations so that the previous formulations to contribute to demonstrating the ulterior ones.

  16. Monitor automatic gauge control strategy with a Smith predictor for steel strip rolling

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The simplified transfer function diagram block for a monitor automatic gauge control (Mon-AGC) system of strip steel rolling process was investigated.The new notion of strip sample length was given.In this way,the delay time varying with the rolling speed was evaded.After a Smith predictor was used to monitor the AGC system,the control laws were deduced for both proportional and integral regulators.The control strategies showed that by choosing the controller parameter P=∞ for both control algorithms each regulator could compensate the whole strip gage error in the first control step.The result shows that the integral algorithm is more controllable for the system regulating process and has a better steady-state precision than the proportional regulator.Compared with the traditional control strategy,the new control laws have a faster response speed and a higher steady-state precision.

  17. Design of a modern automatic control system for the activated sludge process in wastewater treatment

    Institute of Scientific and Technical Information of China (English)

    Alexandros D. Kotzapetros; Panayotis A. Paraskevas; Athanasios S. Stasinakis

    2015-01-01

    The Activated Sludge Process (ASP) exhibits highly nonlinear properties. The design of an automatic control system that is robust against disturbance of inlet wastewater flow rate and has short process settling times is a chal enging matter. The proposed control method is an I-P modified controller automatic control system with state variable feedback and control canonical form simulation diagram for the process. A more stable response is achieved with this type of modern control. Settling times of 0.48 days are achieved for the concentration of microorganisms, (reference value step increase of 50 mg·L−1) and 0.01 days for the concentration of oxygen (reference value step increase of 0.1 mg·L−1). Fluctuations of concentrations of oxygen and microorganisms after an inlet disturbance of 5 × 103m3·d−1 are smal . Changes in the reference values of oxygen and microorganisms (increases by 10%, 20%and 30%) show satisfactory response of the system in al cases. Changes in the value of inlet wastewater flow rate disturbance (increases by 10%, 25%, 50%and 100%) are stabilized by the control system in short time. Maximum percent overshoot is also taken in consideration in all cases and the largest value is 25%which is acceptable. The proposed method with I-P controller is better for disturbance rejection and process settling times compared to the same method using PI control er. This method can substitute optimal control systems in ASP.

  18. Children's Behavioral Pain Cues: Implicit Automaticity and Control Dimensions in Observational Measures

    Science.gov (United States)

    Fashler, Samantha R.

    2017-01-01

    Some pain behaviors appear to be automatic, reflexive manifestations of pain, whereas others present as voluntarily controlled. This project examined whether this distinction would characterize pain cues used in observational pain measures for children aged 4–12. To develop a comprehensive list of cues, a systematic literature search of studies describing development of children's observational pain assessment tools was conducted using MEDLINE, PsycINFO, and Web of Science. Twenty-one articles satisfied the criteria. A total of 66 nonredundant pain behavior items were identified. To determine whether items would be perceived as automatic or controlled, 277 research participants rated each on multiple scales associated with the distinction. Factor analyses yielded three major factors: the “Automatic” factor included items related to facial expression, paralinguistics, and consolability; the “Controlled” factor included items related to intentional movements, verbalizations, and social actions; and the “Ambiguous” factor included items related to voluntary facial expressions. Pain behaviors in observational pain scales for children can be characterized as automatic, controlled, and ambiguous, supporting a dual-processing, neuroregulatory model of pain expression. These dimensions would be expected to influence judgments of the nature and severity of pain being experienced and the extent to which the child is attempting to control the social environment.

  19. Children’s Behavioral Pain Cues: Implicit Automaticity and Control Dimensions in Observational Measures

    Directory of Open Access Journals (Sweden)

    Kamal Kaur Sekhon

    2017-01-01

    Full Text Available Some pain behaviors appear to be automatic, reflexive manifestations of pain, whereas others present as voluntarily controlled. This project examined whether this distinction would characterize pain cues used in observational pain measures for children aged 4–12. To develop a comprehensive list of cues, a systematic literature search of studies describing development of children’s observational pain assessment tools was conducted using MEDLINE, PsycINFO, and Web of Science. Twenty-one articles satisfied the criteria. A total of 66 nonredundant pain behavior items were identified. To determine whether items would be perceived as automatic or controlled, 277 research participants rated each on multiple scales associated with the distinction. Factor analyses yielded three major factors: the “Automatic” factor included items related to facial expression, paralinguistics, and consolability; the “Controlled” factor included items related to intentional movements, verbalizations, and social actions; and the “Ambiguous” factor included items related to voluntary facial expressions. Pain behaviors in observational pain scales for children can be characterized as automatic, controlled, and ambiguous, supporting a dual-processing, neuroregulatory model of pain expression. These dimensions would be expected to influence judgments of the nature and severity of pain being experienced and the extent to which the child is attempting to control the social environment.

  20. Design of a multivariable RF control system using gain-shaping in the frequency domain

    Science.gov (United States)

    Ziomek, C. D.; Jachim, S. P.; Natter, E. F.

    1991-05-01

    Due to the time-varying nature of the radio-frequency (RF) accelerator, RF field amplitude and phase parameters must be precisely controlled in order to confine and accelerate the charged particle beam. Typically, a feedback control system regulates the RF field, rejects noise and disturbances, and maintains operational stability over changes in the electrical structure of the accelerator. This paper describes a multivariable control system that compensates the electrical structure of the accelerator by using gain-shaping in the frequency domain. The amplitude and phase quantities have been resolved into in-phase and quadrature (I and Q) variables. These orthogonal variables have simple mathematical relationships, and can be analyzed using linear transfer function matrices. The transfer matrix theory has been applied to the design of the multivariable control system that regulates the RF field in-phase and quadrature components. Frequency-domain controllers compensate these two signals to provide desired frequency response characteristics. A control predistorter performs an inverse coupling function, so that the I and Q components are effectively decoupled by the accelerator. Furthermore, computer interface circuitry allows the adaptive optimization of the mathematical transfer functions of the compensators.

  1. The systems of automatic weight control of vehicles in the road and rail transport in Poland

    Directory of Open Access Journals (Sweden)

    2011-09-01

    Full Text Available . Condition of roads in Poland, despite the on-going modernisation works is still unsatisfactory. One reason is the excessive wear caused by overloaded vehicles. This problem also applies to rail transport, although to a much lesser extent. One solution may be the system of automatic weight control of road and rail vehicles. The article describes the legal and organizational conditions of oversize vehicles inspection in Poland. Characterized current practices weighing road vehicles, based on measurements of static technology. The article includes the description of the existing applications of the automatic dynamic weighing technology, known as systems WIM (Weigh in Motion. Additionally, the weighing technology and construction of weighing stands in road and rail are characterized. The article ends with authors' conclusions indicating the direction and ways of improving the weighing control systems for vehicles.

  2. Design and Realization of Controllable Ultrasonic Fault Detector Automatic Verification System

    Science.gov (United States)

    Sun, Jing-Feng; Liu, Hui-Ying; Guo, Hui-Juan; Shu, Rong; Wei, Kai-Li

    The ultrasonic flaw detection equipment with remote control interface is researched and the automatic verification system is developed. According to use extensible markup language, the building of agreement instruction set and data analysis method database in the system software realizes the controllable designing and solves the diversification of unreleased device interfaces and agreements. By using the signal generator and a fixed attenuator cascading together, a dynamic error compensation method is proposed, completes what the fixed attenuator does in traditional verification and improves the accuracy of verification results. The automatic verification system operating results confirms that the feasibility of the system hardware and software architecture design and the correctness of the analysis method, while changes the status of traditional verification process cumbersome operations, and reduces labor intensity test personnel.

  3. Automatic Learning of Fine Operating Rules for Online Power System Security Control.

    Science.gov (United States)

    Sun, Hongbin; Zhao, Feng; Wang, Hao; Wang, Kang; Jiang, Weiyong; Guo, Qinglai; Zhang, Boming; Wehenkel, Louis

    2016-08-01

    Fine operating rules for security control and an automatic system for their online discovery were developed to adapt to the development of smart grids. The automatic system uses the real-time system state to determine critical flowgates, and then a continuation power flow-based security analysis is used to compute the initial transfer capability of critical flowgates. Next, the system applies the Monte Carlo simulations to expected short-term operating condition changes, feature selection, and a linear least squares fitting of the fine operating rules. The proposed system was validated both on an academic test system and on a provincial power system in China. The results indicated that the derived rules provide accuracy and good interpretability and are suitable for real-time power system security control. The use of high-performance computing systems enables these fine operating rules to be refreshed online every 15 min.

  4. Results of automatic system implementation for the friction control rods execution in Cofrentes nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Curiel, M. [Logistica y Acondicionamientos Industriales SAU, Sorolla Center, local 10, Av. de las Cortes Valencianas, 46015 Valencia (Spain); Palomo, M. J. [ISIRYM, Universidad Politecnica de Valencia, Camino de Vera s/n, Valencia (Spain); Urrea, M. [Iberdrola Generacion S. A., Central Nuclear Cofrentes, Carretera Almansa Requena s/n, 04662 Cofrentes, Valencia (Spain); Arnaldos, A., E-mail: m.curiel@lainsa.co [TITANIA Servicios Tecnologicos SL, Sorolla Center, local 10, Av. de las Cortes Valencianas No. 58, 46015 Valencia (Spain)

    2010-10-15

    The purpose of this presentation is to show the obtained results in Cofrentes nuclear power plant (Spain) of control rods Pcc/24 friction test procedure. In order to perform this, a control rod friction test system has been developed. Principally, this system consists on software and data acquisition hardware that obtains and analyzes the control rod pressure variation on which the test is being made. The Pcc/24 procedure objective is to detect an excessive friction in the control rod movement that could cause a control rod drive movement slower than usual. This test is necessary every time that an anomalous alteration is produced in the reactor core that could affect to a fuel rod, and it is executed before the time measure of control rods rapid scram test of the affected rods. This test has to be carried out to all the reactor control rods and takes valuable time during plant refuelling. So, by means of an automatic system to perform the test, we obtain an important time saving during refuelling. On the other hand, the on-line monitoring of the control rod insertion and changes in differential pressure, permits a control rod operation fast and safe validation. Moreover, an automatic individual report of every rod is generated by the system and a final global result report of the entire test developed in refuelling is generated. The mentioned reports can be attached directly to the procedure documents obtaining an office data processing important saving time. (Author)

  5. Results of automatic system implementation for the friction control rods execution in Cofrentes nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Palomo, M., E-mail: mpalomo@iqn.upv.es [Universidad Politecnica de Valencia (UPV) (Spain); Urrea, M., E-mail: matias.urrea@iberdrola.es [Iberdrola Generacion S.A. Valencia (Spain). C.N. Cofrentes; Curiel, M., E-mail: m.curiel@lainsa.com [Logistica y Acondicionamientos Industriales (LAINSA), Valencia (Spain); Arnaldos, A., E-mail: a.arnaldos@titaniast.com [TITANIA Servicios Teconologicos, Valencia (Spain)

    2011-07-01

    The purpose of this presentation is to show the obtained results in Cofrentes Nuclear Power Plant (Spain) of Control Rods PCC/24 Friction Test Procedure. In order to perform this, a Control Rod Friction Test System has been developed. Principally, this system consists on software and data acquisition hardware that obtains and analyzes the control rod pressure variation on which the test is being made. The PCC/24 Procedure objective is to detect an excessive friction in the control rod movement that could cause a CRD (Control Rod Drive) movement slower than usual. This test is necessary every time that an anomalous alteration is produced in the reactor core that could affect to a fuel rod, and it is executed before the time measure of control rods rapid scram test of the affected rods. This test has to be carried out to all the reactor control rods and takes valuable time during plant refuelling. So, by means of an automatic system to perform the test, we obtain an important time saving during refuelling. On the other hand, the on-line monitoring of the control rod insertion and changes in differential pressure, permits a control rod operation fast and safe validation. Moreover, an automatic individual report of every rod is generated by the system and a final global result report of the entire test developed in refuelling is generated. The mentioned reports can be attached directly to the procedure documents obtaining an office data processing important saving time.(author)

  6. Automatic control system of brain temperature by air-surface cooling for therapeutic hypothermia.

    Science.gov (United States)

    Utsuki, T

    2013-01-01

    An automatic control system of brain temperature by air-surface cooling was developed for therapeutic hypothermia, which is increasingly recommended for hypoxic-ischemic encephalopathy after cardiac arrest and neonatal asphyxia in several guidelines pertinent to resuscitation. Currently, water-surface cooling is the most widespread cooling method in therapeutic hypothermia. However, it requires large electric power for precise control and also needs water-cooling blankets which have potential for compression of patients by its own weight and for water leakage in ICU. Air-surface cooling does not have such problems and is more suitable for clinical use than water-surface cooling, because air has lower specific heat and density as well as the impossibility of the contamination in ICU by its leakage. In the present system, brain temperature of patients is automatically controlled by suitable adjustment of the temperature of the air blowing into the cooling blankets. This adjustment is carried out by the regulation of mixing cool and warm air using proportional control valves. The computer in the developed control apparatus suitably calculates the air temperature and rotation angle of the valves every sampling time on the basis of the optimal-adaptive control algorithm. Thus, the proposed system actualizes automatic control of brain temperature by the inputting only the clinically desired temperature of brain. The control performance of the suggested system was verified by the examination using the mannequin in substitution for an adult patient. In the result, the control error of the head temperature of the mannequin was 0.12 °C on average in spite of the lack of the production capacity of warm air after the re-warming period. Thus, this system serves as a model for the clinically applied system.

  7. MATHEMATICAL AND COMPUTER MODELING OF AUTOMATIC CONTROL SYSTEM FOR HYDROSTATIC BEARING

    Directory of Open Access Journals (Sweden)

    N. A. Pelevin

    2016-09-01

    Full Text Available The paper presents simulation results of hydrostatic bearing dynamics in spindle assembly of standard flexible production module with throttled circuit. The necessity of dynamic quality increase for automatic control system of the hydrostatic bearing with the use of correcting means in the form of RC-chains is shown. The features of correction parameters choice coming from the existence of the crossing connections in automatic control system structure are noted. We propose the block diagram of automatic control system of the hydrostatic bearing in Simulink working field and cyclic algorithm for determination program of RC-chain parameters implemented in MATLAB taking into account typical thermal processes for the finishing treatment. Graphic-analytical method for the correction parameters choice is presented based on the stability stock phase gradient for dynamic quality determination of automatic control system. Researches of the method estimability in case of using the standard metal bellow valve as the hydrocapacity for RC-chain are also carried out. Recommendations for the bellow valve choice are formulated. The check of dynamic quality indicators concerning transition processes calculated by means of the appropriate programs developed for MATLAB is performed. Examples are given for phase stability factor gradient schedules with partition of various areas of hydrostatic bearing dynamic quality for different frequencies of spindle rotation and procedure description of data cursor function application on MATLAB toolbar. Improvement of hydrostatic bearing dynamics under typical low loadings for finishing treatment is noted. Also, decrease of dynamic indicators for high loadings treatment in case of roughing treatment is marked.

  8. Maximum Power Point Tracking Controller for Thermoelectric Generators with Peak Gain Control of Boost DC-DC Converters

    Science.gov (United States)

    Park, Jungyong; Kim, Shiho

    2012-06-01

    An analog maximum power point tracking (MPPT) circuit for a thermoelectric generator (TEG) is proposed. We show that the peak point of the voltage conversion gain of a boost DC-DC converter with an input voltage source having an internal resistor is the maximum power point of the TEG. The key characteristic of the proposed MPPT controller is that the duty ratio of the input clock pulse to the boost DC-DC converter shifts toward the maximum power point of the TEG by seeking the peak gain point of the boost DC-DC converters. The proposed MPPT technique provides a simple and useful analog MPPT solution, without employing digital microcontroller units.

  9. System design of the METC automatic data acquisition and control system

    Energy Technology Data Exchange (ETDEWEB)

    Goff, D. R.; Armstrong, D. L.

    1982-02-01

    A system of computer programs and hardware was developed by the Instrumentation Branch of the Morgantown Energy Technology Center (METC) to provide data acquisition and control features for research projects at the site. The Automatic Data Acquisition and Control System (ADACS) has the capability of servicing up to eight individual projects simultaneously, providing data acquisition, data feedback, and process control where needed. Several novel software features - including a data table driven program, extensive feedback in real time, free format English commands, and high reliability - were incorporated to provide these functions.

  10. Digital system for automatic control of multi-arm neutron spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Patwardhan, P.K.; Srivastava, H.M.L.; Chawla, H.K.

    1975-01-01

    A flexible system for automatic and Simultaneous control of a Multiarm Neutron Spectrometer has been designed, developed and installed at CIRUS Reactor at Trombay. It controls digitally up to a maximum of nine angular/linear position variable to an accuracy of 0.01/sup 0/. Each variable is associated with one slow speed fractional horsepower bidirectional induction motor. The system receives control data pertaining to the positions of these variable from a preprogrammed paper tape and generates the necessary movement of the motors to set the variable to the desired values. The system employs IC Technology, is computer compatible and has varied applications.

  11. Application of configuration software WinCC in logistics automatic control system

    Science.gov (United States)

    Weng, Yifang; Duan, Zhengang; Lian, Xiaoqin; Zhang, Xiaoli; Yang, Wenying

    2006-11-01

    This paper presents the application of WinCC in Logistics Automatic Control System on the experiment facility of miniature warehouse. The information management system, the supervisory control system and the PLC execution part are developed. The communication between WinCC and PLC based on the PROFIBUS protocol is implemented. DDE Communication, VB as server and WinCC as client, is realized. The system combines information management and supervisory control together and works well. It would be applicable to industry after deeper study.

  12. An approach to the synthesis of separate surface automatic flight control systems.

    Science.gov (United States)

    Roskam, J.; Henry, S.

    1973-01-01

    A method is presented for the analysis of separate surface automatic flight control systems. The feasibility of such systems is demonstrated by the analysis of an example system, a separate surface wing-leveler for a Cessna 172. This example system employs a separate surface aileron with 15% of the basic airplane roll control power. A 90% reduction in bank-angle gust response can be obtained when compared with the basic airplane. The system does not feed back to the pilot's wheel. When failed (even hardover) the pilot retains more than adequate control of the airplane.

  13. DISTURBANCE ERROR INVARIANCE IN AUTOMATIC CONTROL SYSTEMS FOR TECHNOLOGICAL OBJECT TRAJECTORY MOVEMENT

    Directory of Open Access Journals (Sweden)

    A. V. Lekareva

    2016-09-01

    Full Text Available We consider combined control in automatic control systems for technological objects trajectory movements. We present research results of the system disturbance invariance ensuring on the example of the technological manipulator that implements hydrocutting of the oil pipelines. Control is based on the propositions of the fourth modified invariance form with the use of bootstrapping methods. The paper presents analysis of results obtained by two different correction methods. The essence of the first method lies in injection of additional component into the already established control signal and formation of the channel for that component. Control signal correction during the signal synthesis stage in the control device constitutes the basis for the second method. Research results have shown high efficiency of application for both correction methods. Both methods have roughly the same precision. We have shown that the correction in the control device is preferable because it has no influence on the inner contour of the system. We have shown the necessity of the block usage with the variable transmission coefficient, which value is determined by technological trajectory parameters. Research results can be applied in practice for improvement of the precision specifications of automatic control systems for trajectorial manipulators.

  14. Advanced AFCS developments on the XV-15 tilt rotor research aircraft. [Automatic Flight Control System

    Science.gov (United States)

    Churchill, G. B.; Gerdes, R. M.

    1984-01-01

    The design criteria and control and handling qualities of the Automatic Flight Control System (AFCS), developed in the framework of the XV-15 tilt-rotor research aircraft, are evaluated, differentiating between the stability and control criteria. A technically aggressive SCAS control law was implemented, demonstrating that significant benefits accrue when stability criteria are separated from design criteria; the design analyses for application of the control law are presented, and the limit bandwidth for stabilization in hovering flight is shown to be defined by rotor or control lag functions. Flight tests of the aircraft resulted in a rating of 3 on the Cooper-Harper scale; a possibility of achieving a rating of 2 is expected if the system is applied to the yaw and heave control modes.

  15. Study on Rear-end Real-time Data Quality Control Method of Regional Automatic Weather Station

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The aim was to study the rear-end real-time data quality control method of regional automatic weather station. [Method] The basic content and steps of rear-end real-time data quality control of regional automatic weather station were introduced. Each element was treated with systematic quality control procedure. The existence of rear-end real time data of regional meteorological station in Guangxi was expounded. Combining with relevant elements and linear changes, improvement based on traditiona...

  16. [Open loop gain of the CO2-ventilation feedback control system in chronic obstructive pulmonary disease].

    Science.gov (United States)

    Kimura, H; Kunitomo, F; Okita, S; Tojima, H; Tatsumi, K; Kuriyama, T; Hashizume, I; Honda, Y

    1989-07-01

    To evaluate the stability of the CO2-ventilation feedback system, we measured its open loop gain (G) in 12 patients with chronic obstructive pulmonary disease (COPD) and 15 control subjects. Then, we compared G to the conventional slope of the CO2-ventilation response line (S) and that of the metabolic hyperbola (SL). G was determined as the ratio of S to SL by applying external dead space of 250 and 500 ml. G, S and 1/SL in the control and the COPD were +17.1 +/- 7.2 (Mean +/- SD), 1.70 +/- 0.75 L.min-1.Torr-1 and -10.4 +/- 2.0 L-1.min.Torr, and -7.2 +/- 3.3, 0.48 +/- 0.27 L.min-1.Torr-1 and -16.1 +/- 6.4 L-1.min.Torr, respectively. G was significantly correlated with S in both groups, but that was not the case in 1/SL. The magnitude of G and S in COPD was about 42% and 28% of the control, indicating that G was maintained more stable than S. These data suggest that the decreased G in the COPD resulted from insufficient compensation of ventilatory drive, whereas 1/SL increased higher than the control. We conclude that G can be used to indicate the stability of the CO2-ventilation feedback system better than S.

  17. CLOSED LOOP CONTROL OF THREE PORT CONVERTER WITH HIGH VOLTAGE GAIN

    Directory of Open Access Journals (Sweden)

    Santhi Mary Antony A

    2015-08-01

    Full Text Available Photovoltaic (PV system is one of the best renewable energy sources for power generation system due to their pollution free and low cost properties. The PV cells has less efficiency compared to other source of power generation. The system efficiency is improved by reducing components count, which reduces the losses. In this paper a new three port converter (TPC is proposed for stand-alone renewable power applications. The proposed converter has three switches to achieve the power flow control. Single inductor is used for common energy transfer element for two different sources. The coupled inductor is used to increase the voltage conversion ratio with reasonable duty cycle. Thus the proposed converter has high voltage gain with less components count. The output voltage is regulated through feedback network. The system performance is verified through simulation results.

  18. A wideband LC-VCO with small VCO gain variation and adaptive power control

    Institute of Scientific and Technical Information of China (English)

    Li Bin; Fan Xiangning; Wang Zhigong

    2012-01-01

    A wideband LC tank voltage-controlled-oscillator (VCO) is proposed.To solve the impacts ofwideband operation on VCO gain (Kvco) variation and start-up constraint,a binary-weighted varactor array and a binary-weighted negative resistance array all with optimal unit values are designed.Implemented in a 0.18 μm CMOS process,the proposed VCO shows a frequency tuning range from 1.9 to 3.1 GHz,with a current consumption varying accordingly from 14.2 to 4 mA from a 1.8 V supply.With the proposed Kvco suppression technique,the Kvco varies from 50 to 60 MHz/V in the entire frequency range.The measured phase noise is -117 dBc/Hz at a 1 MHz offset from a 3 GHz carrier.

  19. Automatic Calibration of Frequency Compensation System in Computer-Controlled Patch-Clamp Amplifier

    Directory of Open Access Journals (Sweden)

    Jun Xion

    2007-01-01

    Full Text Available Computer-controlled patch-clamp amplifier is a digitally controlled analog device used to record the cellular ion channel currents in electrophysiology research. The inherent bandwidth and performance of the headstage is limited by the stray capacitance and distributed capacitance across the feedback resistors. In order to effectively improve the performance of the headstage, the paper advanced a simplified automatic calibration method of frequency compensation system in resistor-feedback patch-clamp amplifier. The dynamic model of headstage was approximate as a two poles and one zero system in the transfer function by experience and test results, so the dynamic characteristics of the headstage were obtained employing least squares parameter estimation algorithm. Further more, the compensation parameter of high frequency booster can be estimated by the time constant of main pole of headstage. And automatic adjustment of the parameters in transient response correction stage was performed as a least squares fitting problem. The software routine running on the host computer conducted all operations of frequency compensation. Experimental results demonstrate that the simplified automatic calibration method can substantially extend the bandwidth and minimize step response error of headstage.

  20. Automatic learning rate adjustment for self-supervising autonomous robot control

    Science.gov (United States)

    Arras, Michael K.; Protzel, Peter W.; Palumbo, Daniel L.

    1992-01-01

    Described is an application in which an Artificial Neural Network (ANN) controls the positioning of a robot arm with five degrees of freedom by using visual feedback provided by two cameras. This application and the specific ANN model, local liner maps, are based on the work of Ritter, Martinetz, and Schulten. We extended their approach by generating a filtered, average positioning error from the continuous camera feedback and by coupling the learning rate to this error. When the network learns to position the arm, the positioning error decreases and so does the learning rate until the system stabilizes at a minimum error and learning rate. This abolishes the need for a predetermined cooling schedule. The automatic cooling procedure results in a closed loop control with no distinction between a learning phase and a production phase. If the positioning error suddenly starts to increase due to an internal failure such as a broken joint, or an environmental change such as a camera moving, the learning rate increases accordingly. Thus, learning is automatically activated and the network adapts to the new condition after which the error decreases again and learning is 'shut off'. The automatic cooling is therefore a prerequisite for the autonomy and the fault tolerance of the system.

  1. The AST3 controlling and operating software suite for automatic sky survey

    Science.gov (United States)

    Hu, Yi; Shang, Zhaohui; Ma, Bin; Hu, Keliang

    2016-07-01

    We have developed a specialized software package, called ast3suite, to achieve the remote control and automatic sky survey for AST3 (Antarctic Survey Telescope) from scratch. It includes several daemon servers and many basic commands. Each program does only one single task, and they work together to make AST3 a robotic telescope. A survey script calls basic commands to carry out automatic sky survey. Ast3suite was carefully tested in Mohe, China in 2013 and has been used at Dome, Antarctica in 2015 and 2016 with the real hardware for practical sky survey. Both test results and practical using showed that ast3suite had worked very well without any manual auxiliary as we expected.

  2. Automatic control systems for submerged membrane bioreactors: a state-of-the-art review.

    Science.gov (United States)

    Ferrero, Giuliana; Rodríguez-Roda, Ignasi; Comas, Joaquim

    2012-07-01

    Membrane bioreactor (MBR) technology has become relatively widespread as an advanced treatment for both industrial and municipal wastewater, especially in areas prone to water scarcity. Although operational cost is a key issue in MBRs, currently only a few crucial papers and inventions aimed to optimise and enhance MBR efficiency have been published. The present review summarises the available solutions in the area of automatic control systems and widely explores the advances in automation and control for MBRs. In this review of state of the art, different control systems are evaluated comparatively, distinguishing between control systems used for the filtration process and those used for the biological process of MBRs and describing the challenge faced by integrated control systems. The existing knowledge is classified according to the manipulated variables, the operational mode (open-loop or closed-loop) and the controlled variables used.

  3. Application of Nonlinear Systems Inverses to Automatic Flight Control Design: System Concepts and Flight Evaluations

    Science.gov (United States)

    Meyer, G.; Cicolani, L.

    1981-01-01

    A practical method for the design of automatic flight control systems for aircraft with complex characteristics and operational requirements, such as the powered lift STOL and V/STOL configurations, is presented. The method is effective for a large class of dynamic systems requiring multi-axis control which have highly coupled nonlinearities, redundant controls, and complex multidimensional operational envelopes. It exploits the concept of inverse dynamic systems, and an algorithm for the construction of inverse is given. A hierarchic structure for the total control logic with inverses is presented. The method is illustrated with an application to the Augmentor Wing Jet STOL Research Aircraft equipped with a digital flight control system. Results of flight evaluation of the control concept on this aircraft are presented.

  4. The application of ANN technique to automatic generation control for multi-area power system

    Energy Technology Data Exchange (ETDEWEB)

    Zeynelgil, H.L.; Demiroren, A.; Sengor, N.S. [Istanbul Technical Univ., Maslak (Turkey). Electrical and Electronic Faculty

    2002-06-01

    This paper presents an application of layered artificial neural network controller (ANN) to study automatic generation control (AGC) problem in a four-area interconnected power system that three areas include steam turbines and the other area includes a hydro turbine. Each area of steam turbine in the system contains the reheat effect non-linearity of the steam turbine and the area of hydro turbine contains upper and lower constraints for generation rate. Only one ANN controller, which controls the inputs of each area in the power system together, is considered. In the study, back propagation-through-time algorithm is used as ANN learning rule. By comparing the results for both cases, the performance of ANN controller is better than conventional controllers. (author)

  5. STUDY ON THE AUTOMATIC REGULATION SYSTEM OF WIND RATE FUZZY CONTROL

    Institute of Scientific and Technical Information of China (English)

    李敬兆; 张崇巍; 周时欢; 王清灵

    2000-01-01

    This paper presents the solution of regulating the wind rate automatically by means of fuzzy control technology and implementing it with PLC (programmable logical controller) under the circumstance of many influence factors, which exists in the axial-flow fans wind rate regulation system during the process of mine ventilation, and has difficulty in modifying the mathematic model to obtain the satisfied result by normal control ways. According to this analysis, the intelligent and analytic treatment of fuzzy controller has been made and fuzzy control scheme involving self-regulation divisor and intelligent integral has been deeply proposed. Test result shows that this system based on the scheme above is obviously prior to others in its responsibility such as high-speed, overshoot, control precision and robustness. The system furnishes the great reliability of mine working safety and fans running efficiency.

  6. Automatic Control System of Ion Electrostatic Accelerator and Anti-Interference Measures

    Institute of Scientific and Technical Information of China (English)

    SUN Zhenwu; HUO Yuping; LIU Gencheng; LI Yuxiao; LI Tao

    2007-01-01

    An automatic control system for the electrostatic accelerator has been developed by adopting the PLC (Programmable Logic Controller) control technique, infrared and optical-fibre transmission technique and network communication with the purpose to improve the intelligence level of the accelerator and to enhance the ability of monitoring, collecting and recording parameters. In view of the control system' structure, some anti-interference measures have been adopted after analyzing the interference sources. The measures in hardware include controlling the position of the corona needle, using surge arresters, shielding, ground connection and stabilizing the voltage. The measures in terms of software involve inter-blocking protection, soft-spacing, time delay, and diagnostic and protective programs. The electromagnetic compatible ability of the control system, has thus been effectively improved.

  7. Automatic control of freeboard and turbine operation. Wave Dragon, Nissum Bredning

    Energy Technology Data Exchange (ETDEWEB)

    Kofoed, Jens Peter; Frigaard, P. [Aalborg Univ. (Denmark); Friis-Madsen, Erik [Wave Dragon ApS (Denmark); Nimskov, M. [Balslev (Denmark)

    2004-02-01

    This report deals with the modules for automatic control of freeboard and turbine operation on board the Wave Dragon, Nissum Bredning (WD-NB) prototype, and covers what has been going on up to ultimo 2003. The modules have been implemented on board WD-NB by means of a Siemens PLC. The control and monitoring of the PLC is achieved through a SCADA software package (SIMATIC WinCC V6) running on a Windows 2000 PC situated on board. A preliminary Users manual is available (Nimskov, 2003). The two modules for automatic control of freeboard and turbine operation are denoted 'Buoyancy' and 'Generators', respectively, in the SCADA system. The 'Buoyancy' part controls the freeboard by blowing air into or letting air out of air chambers underneath the structure, and thereby raise or lower it. The 'generator' part controls the generators, and thereby the turbines, by switching them on and of in order to maintain the water level in the reservoir within the specified work span. Furthermore, the generators are controlled by frequency converters, so the rotational speed for each turbine is achieved, corresponding to the optimal operation point. (au)

  8. Design and Implementation of Electrostatic Spraying Automatic Controlling System Based on PLC

    Directory of Open Access Journals (Sweden)

    Weidong Jia

    2013-05-01

    Full Text Available The objective of this study was to improve the spraying efficiency and meet the demand of modern agricultural. A new generation of electrostatic sprayer which we designed realized the goals. The automatic controlling system is successfully designed. PLC (Programmable Logic Controller was taken as the control core of the system and LCD touch screen was employed for human-computer interaction interface. The system integrates kinds of techniques including programming, pressure monitoring and sensor technology, etc. The main structure of this equipment, working principle and control system hardware selection will be also introduced in the study. Human-computer interaction software was programmed by the software of Pro Tool/Pro CS. System controlling software was programmed in form of ladder diagram, which realized kinds of functions including ESD protection, accurate quantification, automatic controlling and humanized operation. Test results show that the effective spraying range is between 5 to 6 m, the Volume Median Diameter (VMD is 47.48 µm and the Ultra-Low Volume spray (ULV is realized. The spray deposition rate and effective availability of pesticide is higher than old sprayer. And also this new sprayer runs steadily.

  9. Multi-Stage Optimization Based Automatic Voltage Control Systems Considering Wind Power Forecasting Errors

    DEFF Research Database (Denmark)

    Qin, Nan; Bak, Claus Leth; Abildgaard, Hans

    2017-01-01

    cost and the generator reactive power output cost. The problem is formulated in a multi-stage optimal reactive power flow (MORPF) framework, solved by the nonlinear programming techniques via a rolling process. The voltage uncertainty caused by wind power forecasting errors is considered in the optimal......This paper proposes an automatic voltage control (AVC) system for power systems with limited continuous voltage control capability. The objective is to minimize the operational cost over a period, which consists of the power loss in the grid, the shunt switching cost, the transformer tap change...

  10. Automatic control of human thermal comfort with a liquid-cooled garment

    Science.gov (United States)

    Kuznetz, L. H.

    1977-01-01

    Water cooling in a liquid-cooled garment is used to maintain the thermal comfort of crewmembers during extravehicular activity. The feasibility of a simple control that will operate automatically to maintain the thermal comfort is established. Data on three test subjects are included to support the conclusion that heat balance can be maintained well within allowable medical limits. The controller concept was also successfully demonstrated for ground-based applications and shows potential for any tasks involving the use of liquid-cooled garments.

  11. A Prototype Automatic Solar Panel Controller (ASPC with Night-time Hibernation

    Directory of Open Access Journals (Sweden)

    Salihu O. Aliyu

    2016-08-01

    Full Text Available Solar cells, as an alternate means of electricity supply, is rapidly advancing. Generally, output of solar cells depends largely on intensity of sun and angle of incidence on the cells. This means that to get maximum efficiency from these cells, they must remain directly pointed at the sun from sun rise to sun set. However, the position of sun‟s highest intensity with respect to a given spot changes with time of the day. It is therefore necessary to automatically control position of solar cells to always align with the highest intensity of sun. In this paper, we present a prototype automatic solar panel controller, with night time hibernation. The proposed system consists of both software and hardware parts, and it automatically provides best alignment of solar panel with sun to get maximum intensity. The solar panel controller system detects the presence of sun rays using light dependent resistors (LDR. At the heart of the control mechanism is an AT89C52 microcontroller. It is programmed to constantly monitor the output of an LDR, actuate a stepper motor to reposition the solar panel to a direction with the highest intensity. The proposed system also has an option of manual control of the panel via a computer interface or a keypad unit for easy of user interactivity during maintenance. Testing the proposed system, results shows that it can successfully track the sun and enter idle mode in the absence of sun rays, hence, conserving over 50% of energy required to operate the system.

  12. Controllable optical response by modifying the gain and loss of a mechanical resonator and cavity mode in an optomechanical system

    CERN Document Server

    Liu, Yu-Long; Zhang, Jing; Özdemir, Şahin Kaya; Yang, Lan; Nori, Franco; Liu, Yu-xi

    2016-01-01

    We theoretically study a strongly-driven optomechanical system which consists of a passive optical cavity and an active mechanical resonator. When the optomechanical coupling strength is varied, phase transitions, which are similar those observed in $\\mathcal{PT}$-symmetric systems, are observed. We show that the optical transmission can be controlled by changing the gain of the mechanical resonator and loss of the optical cavity mode. Especially, we find that: (i) for balanced gain and loss, optical amplification and absorption can be tuned by changing the optomechanical coupling strength through a control field; (ii) for unbalanced gain and loss, even with a tiny mechanical gain, both optomechanically-induced transparency and anomalous dispersion can be observed around a critical point, which exhibits an ultra-long group delay. The time delay $\\tau$ can be optimized by regulating the optomechanical coupling strength through the control field and improved up to several orders of magnitude ($\\tau\\sim2$ $\\math...

  13. Automatic Generation Control in Multi Area Interconnected Power System by using HVDC Links

    Directory of Open Access Journals (Sweden)

    Yogendra Arya

    2012-01-01

    Full Text Available This paper investigates the effects of HVDC link in parallel with HVAC link on automatic generation control (AGC problem for a multi-area power system taking into consideration system parameter variations. A fuzzy logic controller is proposed for four area power system interconnected via parallel HVAC/HVDC transmission link which is also referred as asynchronous tie-lines. The linear model of HVAC/HVDC link is developed and the system responses to sudden load change are studied. The simulation studies are carried out for a four area interconnected thermal power system. Suitable solution for automatic generation control problem of four area electrical power system is obtained by means of improving the dynamic performance of power system under study. Robustness of controller is also checked by varying parameters. Simulation results indicate that the scheme works well. The dynamic analyses have been done with and without HVDC link using fuzzy logic controller in Matlab-Simulink. Further a comparison between the two is presented and it has been shown that the performance of the proposed scheme is superior in terms of overshoot and settling time.

  14. Electric Drive Discrete Control System with Automatic Switching-On Reserve for Autonomous Settlement

    Directory of Open Access Journals (Sweden)

    Tsytovich L.I.

    2015-08-01

    Full Text Available The paper aims at developing of control the water supply system’s electric drives for autonomous settlement. The system provides automatic switching to a reserve control channel at refusal of any of the functional elements of the working regulation channel. Usually, such systems have a test signal generator and analyzer to system response to their impact. This result to an increase in the structural redundancy of the system, increase its cost and increase the requirements for the staff qualification. A specific feature of the system is its ability to self-diagnosis of catastrophic malfunctions of scheme’s components and an automatic switching-on the reserve control channels, without applying any test signals to the whole complex of electrical equipment. Multi-zone integrating regulator with frequency-pulse-width modulation realizes this technical solution. Control system structure and signals timing diagrams are presented. The construction principle of adaptive interval-code synchronization device with improved noise stability to control the voltage regulators serving for smooth start-up of asynchronous motors of water pumps is considered as well. Such solution allowing increase noise stability and reliability work of the system in conditions of limited power electrical networks, which is characteristic for the autonomous settlements. The article may be of interest to specialists in the field of power electronics and information electronics, electric drives and process automation.

  15. Application of GA optimization for automatic generation control design in an interconnected power system

    Energy Technology Data Exchange (ETDEWEB)

    Golpira, H., E-mail: hemin.golpira@uok.ac.i [Department of Electrical and Computer Engineering, University of Kurdistan, Sanandaj, PO Box 416, Kurdistan (Iran, Islamic Republic of); Bevrani, H. [Department of Electrical and Computer Engineering, University of Kurdistan, Sanandaj, PO Box 416, Kurdistan (Iran, Islamic Republic of); Golpira, H. [Department of Industrial Engineering, Islamic Azad University, Sanandaj Branch, PO Box 618, Kurdistan (Iran, Islamic Republic of)

    2011-05-15

    Highlights: {yields} A realistic model for automatic generation control (AGC) design is proposed. {yields} The model considers GRC, Speed governor dead band, filters and time delay. {yields} The model provides an accurate model for the digital simulations. -- Abstract: This paper addresses a realistic model for automatic generation control (AGC) design in an interconnected power system. The proposed scheme considers generation rate constraint (GRC), dead band, and time delay imposed to the power system by governor-turbine, filters, thermodynamic process, and communication channels. Simplicity of structure and acceptable response of the well-known integral controller make it attractive for the power system AGC design problem. The Genetic algorithm (GA) is used to compute the decentralized control parameters to achieve an optimum operating point. A 3-control area power system is considered as a test system, and the closed-loop performance is examined in the presence of various constraints scenarios. It is shown that neglecting above physical constraints simultaneously or in part, leads to impractical and invalid results and may affect the system security, reliability and integrity. Taking to account the advantages of GA besides considering a more complete dynamic model provides a flexible and more realistic AGC system in comparison of existing conventional schemes.

  16. Automatic Control Systems (ACS for Generation and Sale of Electric Power Under Conditions of Industry-Sector Liberalization

    Directory of Open Access Journals (Sweden)

    Yu. Petrusha

    2013-01-01

    Full Text Available Possible risks pertaining to transition of electric-power industry to market relations have been considered in the paper. The paper presents an integrated ACS for generation and sale of electric power as an improvement of methodology for organizational and technical management. The given system is based on integration of operating Automatic Dispatch Control System (ADCS and developing Automatic Electricity Meter Reading System (AEMRS. The paper proposes to form an inter-branch sector of ACS PLC (Automatic Control System for Prolongation of Life Cycle users which is oriented on provision of development strategy.

  17. Robust on-line relay automatic tuning of PID control systems

    Science.gov (United States)

    Tan; Lee; Jiang

    2000-01-01

    In this paper, a robust on-line relay automatic tuning method for PID control systems is developed which expand on the application domain of Astrom's renowned relay autotuning method. In the proposed configuration, a relay is applied to an inner loop of a controller-stabilised process in the usual manner. Using the induced limit cycle oscillations from the closed-loop system, the controller settings may be re-tuned non-iteratively to achieve enhanced performance without disrupting closed-loop control. Two control tuning methodologies are developed -- a direct and an indirect method based on an explicit process model. Simulation examples and a real-time experiment are provided to illustrate the practical appeal and potential advantages of the proposed method over the basic one.

  18. Decentralized automatic generation control of interconnected power systems incorporating asynchronous tie-lines.

    Science.gov (United States)

    Ibraheem; Hasan, Naimul; Hussein, Arkan Ahmed

    2014-01-01

    This Paper presents the design of decentralized automatic generation controller for an interconnected power system using PID, Genetic Algorithm (GA) and Particle Swarm Optimization (PSO). The designed controllers are tested on identical two-area interconnected power systems consisting of thermal power plants. The area interconnections between two areas are considered as (i) AC tie-line only (ii) Asynchronous tie-line. The dynamic response analysis is carried out for 1% load perturbation. The performance of the intelligent controllers based on GA and PSO has been compared with the conventional PID controller. The investigations of the system dynamic responses reveal that PSO has the better dynamic response result as compared with PID and GA controller for both type of area interconnection.

  19. INVARIAN AUTOMATIC CONTROL SYSTEM, USING THE INTERMEDIATE-FREQUENCY SIGNALS OF HEAT POWER PARAMETERS

    Directory of Open Access Journals (Sweden)

    G. T. Kulakov

    2015-01-01

    Full Text Available The usage of digital micro-processing automatic means allow to use design methods (technique of automatic control systems  more wider, and also to apply optimal ways of control, for example, it is possible to combine the Method of structural-parameter optimization and invariance theory. This method allow to increase essential system speed in processing of task jump and to reduce operation time of outside external disturbance up to two  values of regulated influence, and the usage of invariance principle is based on an additional measuring of the most dangerous perturbation influence and in connection with it the improvement of regulation quality is achieved.In this article the principle of invariance is applied in order to improve greatly external disturbance attack by consumption of over-heated steam. Compensation of disturbance influence on regulated value is achieving by introduction of additional signal on input of correction regulator from output of compensation device, measuring the external disturbance by consumption of over-heated steam.Modeling results of transient processes of cascade system of automatic control (CSAC, on the base of which were realized the unity of these methods, demonstrated the fact that, in processing of external disturbance by consumption of steam, the reduction of maximal dynamic regulation error is six times and cutting of regulation time by 30 % in comparison with CSAC without compensation device of external disturbance. And that is why it leads to the further reduction of maximal dynamic regulation error in processing of external disturbance by consumption of steam, and this allows to improve the quality of control.

  20. Controlling the dynamical behavior of nonlinear fiber ring resonators with balanced loss and gain

    CERN Document Server

    Deka, Jyoti P; Sarma, Amarendra K

    2015-01-01

    We show the possibility of controlling the dynamical behavior of a single fiber ring (SFR) resonator system with the fiber being an amplified (gain) channel and the ring being attenuated (loss) nonlinear dielectric medium. The system considered here is a simple alteration in the basic building block of the parity time (PT) symmetric synthetic coupler structures reported in A. Regensburger et al., Nature 488, 167 (2012). We find that this result in a dynamically controllable algorithm for the chaotic dynamics inherent in the system. We have also shown the dependence of the period doubling point upon the input amplitude, emphasizing on the dynamical aspects of our system. Moreover, the fact that the resonator essentially plays the role of a damped harmonic oscillator has been elucidated with the non-zero intensity inside the resonator due to constant influx of input light. This study may be a step forward to further investigations in regard to the inter-connectivity between the PT symmetry and chaos along with ...

  1. Controlling the gain shape of Er3+-doped fluorozirconate fibre amplifier by a coherent field

    Institute of Scientific and Technical Information of China (English)

    张惠芳; 吴金辉; 高锦岳

    2003-01-01

    We proposed a four-level system to explore the quantum interference effects on optical amplification. We found that the gain of the probe, including positions and values of gain peaks, can be adjusted by changing the coherent field and the incoherent pumping. At the same time, we can also modify the absorption profile of electromagnetically induced transparency by the incoherent pump. The results provide a method to flatten the gain of Erbium-doped fibre amplifiers.

  2. Automatic control with fuzzy logic of home-made beer production in maceration and cooking stages

    Directory of Open Access Journals (Sweden)

    Mariano Luján Corro

    2010-06-01

    Full Text Available The process of home-made beer production in the malt maceration and cooking stages was controlled automatically with fuzzy logic, across different performers considering the time and temperature of the process, using 2009LabVIEW. The equipment was mainly composed of three 20 L capacity stainless steel containers (water supply, maceration and cooking, an additional hops container, a data acquisition card (PIC 16F877a micro controller, three LM35 temperature sensors and 11 on/off type performers, which were governed by a total of 47 Mandani type fuzzy rules with trapezoidal membership functions, using the method of center area for the defuzzification. The performers: electrovalves (5, pumps (2, heaters (3 and a stirrer, in approximately 4 hours, were adequately controlled in their early maceration and cooking stages. The beer obtained by automatic control with fuzzy logic in the maceration and cooking stages, had the following characteristics: 0.98 g/cm3 of density, 3.9 of pH, total acidity expressed as 0.87% of lactic acid, 6.2ºGL of alcoholic degree and 0.91% w/v of CO2 percentage.

  3. A new adjustable gains for second order sliding mode control of saturated DFIG-based wind turbine

    Science.gov (United States)

    Bounadja, E.; Djahbar, A.; Taleb, R.; Boudjema, Z.

    2017-02-01

    The control of Doubly-Fed induction generator (DFIG), used in wind energy conversion, has been given a great deal of interest. Frequently, this control has been dealt with ignoring the magnetic saturation effect in the DFIG model. The aim of the present work is twofold: firstly, the magnetic saturation effect is accounted in the control design model; secondly, a new second order sliding mode control scheme using adjustable-gains (AG-SOSMC) is proposed to control the DFIG via its rotor side converter. This scheme allows the independent control of the generated active and reactive power. Conventionally, the second order sliding mode control (SOSMC) applied to the DFIG, utilize the super-twisting algorithm with fixed gains. In the proposed AG-SOSMC, a simple means by which the controller can adjust its behavior is used. For that, a linear function is used to represent the variation in gain as a function of the absolute value of the discrepancy between the reference rotor current and its measured value. The transient DFIG speed response using the aforementioned characteristic is compared with the one determined by using the conventional SOSMC controller with fixed gains. Simulation results show, accurate dynamic performances, quicker transient response and more accurate control are achieved for different operating conditions.

  4. Developing an intelligent control system of automatic window motor with diverse wireless sensor network devices

    Indian Academy of Sciences (India)

    Yao-Chiang Kan; Hsueh-Chun Lin; Wen-Pei Sung

    2014-08-01

    This invention system involves hardware, firmware and software to develop an intelligent control system of automatic window motor with diverse wireless sensor network (WSN) devices for health and environmental monitoring. The parts of this invention are improved by implementing the WSN mote into environmental sensors that may detect temperature, humility, toxic gas, smog or aerosol, etc. With embedded system design, these sensors are capable of delivering WSN signal packets based on ZigBee protocol that follows the IEEE 802.14.4 standards. The primary hardware of the system is the window motor with circuit design by integrating micro control unit (MCU), radio frequency (RF) and WSN antenna to receive command. The firmware developed under embedded system can bridge hardware and software to control the window at the specified position. At the back end, the control system software can manage diverse sensor data and provide the interface for remote monitoring.

  5. OPTIMAL TORQUE CONTROL STRATEGY FOR PARALLEL HYBRID ELECTRIC VEHICLE WITH AUTOMATIC MECHANICAL TRANSMISSION

    Institute of Scientific and Technical Information of China (English)

    GU Yanchun; YIN Chengliang; ZHANG Jianwu

    2007-01-01

    In parallel hybrid electrical vehicle (PHEV) equipped with automatic mechanical transmission (AMT), the driving smoothness and the clutch abrasion are the primary considerations for powertrain control during gearshift and clutch operation. To improve these performance indexes of PHEV, a coordinated control system is proposed through the analyzing of HEV powertrain dynamic characteristics. Using the method of minimum principle, the input torque of transmission is optimized to improve the driving sinoothness of vehicle. Using the methods of fuzzy logic and fuzzy-PID, the engaging speed of clutch and the throttle opening of engine are manipulated to ensure the smoothness of clutch engagement and reduce the abrasion of clutch friction plates. The motor provides the difference between the required input torque of transmission and the torque transmitted through clutch plates. Results of simulation and experiments show that the proposed control strategy performs better than the contrastive control system, the smoothness of driving and the abrasion of clutch can be improved simultaneously.

  6. Digital controller for a Baum folding machine. [providing automatic counting and machine shutoff

    Science.gov (United States)

    Bryant, W. H. (Inventor)

    1974-01-01

    A digital controller for controlling the operation of a folding machine enables automatic folding of a desired number of sheets responsive to entry of that number into a selector. The controller includes three decade counter stages for corresponding rows of units, tens and hundreds push buttons. Each stage including a decimal-to-BCD encoder, a buffer register, and a digital or binary counter. The BCD representation of the selected count for each digit is loaded into the respective decade down counters. Pulses generated by a sensor and associated circuitry are used to decrease the count in the decade counters. When the content of the decade counter reaches either 0 or 1, a solenoid control valve is actuated which interrupts operation of the machine. A repeat switch, when actuated, prevents clearing of the buffer registers so that multiple groups of the same number of sheets can be folded without reentering the number into the selector.

  7. Automatic control systems of daylighting and artificial lighting; Saiko shomei setsubi no seigyo system

    Energy Technology Data Exchange (ETDEWEB)

    Saito, M. [Obayashi Corp., Tokyo (Japan)

    1997-06-05

    Means for controlling illumination include a blind for adjusting the light coming directly from the sun, system for maintaining environmental comfort by controlling light-modulating glass and the like, labor-saving system incorporating a control center governing multiple buildings in the vicinity, and system intended for improved energy efficiency. Energy saving efforts include an occupancy sensor control for the automatic turn-on/off of lighting by detecting the presence or absence of people in a chamber, optimum lighting control using sensors for adjusting illumination to the designed level, time-scheduled control for the turning-on/off of lighting according to the time of the day, daylight utilizing control for adjusting artificial lighting according to the amount of incident daylight, guidance light control system for turning on guidance lights upon sensing a decrease in incident daylight. Other than these, there are controls of lighting for performance and demonstration. Examples of practical application include the system adopted by Museum of Contemporary Art, Tokyo, for keeping incident light homogeneous, and the optimum illumination control and daylight utilizing control of Research & Development Center, The Tokyo Electric Power Co., Ltd. 8 refs., 10 figs.

  8. X-ray detector for automatic exposure control using ionization chamber filled with xenon gas

    CERN Document Server

    Nakagawa, A; Yoshida, T

    2003-01-01

    This report refers to our newly developed X-ray detector for reliable automatic X-ray exposure control, which is to be widely used for X-ray diagnoses in various clinical fields. This new detector utilizes an ionization chamber filled with xenon gas, in contrast to conventional X-ray detectors which use ionization chambers filled with air. Use of xenon gas ensures higher sensitivity and thinner design of the detector. The xenon gas is completely sealed in the chamber, so that the influence of the changes in ambient environments is minimized. (author)

  9. Automatic control system of high precision welding of workpieces in mechanical engineering

    Science.gov (United States)

    Kuznetsov, I. N.; Zvezdin, V. V.; Israfilov, I. H.; Portnov, S. M.

    2014-12-01

    In this paper, based on the conducted patent research, the system of laser welding control with different geometry of weld and shapes of parts is developed. The method of monitoring the position of the spot of laser radiation in relation to the curved weld is worked out; it is based on the tracking the edges of the welded parts by low-power laser radiation reflected from the surface of the parts. It allows to make the positioning of the focus of laser radiation in relation to the juncture of the welded parts automatically.

  10. Automatic Shape Control of Triangular B-Splines of Arbitrary Topology

    Institute of Scientific and Technical Information of China (English)

    Ying He; Xian-Feng Gu; Hong Qin

    2006-01-01

    Triangular B-splines are powerful and flexible in modeling a broader class of geometric objects defined over arbitrary, non-rectangular domains. Despite their great potential and advantages in theory, practical techniques and computational tools with triangular B-splines are less-developed. This is mainly because users have to handle a large number of irregularly distributed control points over arbitrary triangulation. In this paper, an automatic and efficient method is proposed to generate visually pleasing, high-quality triangular B-splines of arbitrary topology. The experimental results on several real datasets show that triangular B-splines are powerful and effective in both theory and practice.

  11. Using fuzzy logic for automatic control: Case study of a problem of cereals samples classification

    Directory of Open Access Journals (Sweden)

    Lakhoua Najeh Mohamed

    2009-01-01

    Full Text Available The aim of this paper is to present the use of fuzzy logic for automatic control of industrial systems particularly the way to approach a problem of classification. We present a case study of a grading system of cereals that allows us to determine the price of transactions of cereals in Tunisia. Our contribution in this work consists in proposing not only an application of the fuzzy logic on the grading system of cereals but also a methodology enabling the proposing of a new grading system based on the concept of 'Grade' while using the fuzzy logic techniques. .

  12. An automatic system for controlling the quality of straws installed in the ATLAS TRT detector

    CERN Document Server

    Golunov, A O; Gousakov, Yu V; Kekelidze, G D; Livinski, V V; Mouraviev, S V; Parzycki, S S; Peshekhonov, V D; Price, M J; Savenkov, A A

    2004-01-01

    This article describes an automatic system to control the quality of straws installed in the wheels of the end-cap Transition Radiation Tracker of the ATLAS experiment. The system tests both the straightness and the electrical insulation of the straws during installation. The testing time per straw is 9s; consequently it takes about 2h to measure one layer of straws. The off-line analysis takes 20s per straw. With this system defects can be immediately detected and corrected. This clearly influences the future performance of the detector.

  13. DFIG-Based Wind Turbine Robust Control Using High-Order Sliding Modes and a High Gain Observer

    OpenAIRE

    Beltran, Brice; Benbouzid, Mohamed; Ahmed-Ali, Tarek; Mangel, Hervé

    2011-01-01

    International audience; This paper deals with the power generation control in variable speed wind turbines. In this context, a control strategy is proposed to ensure power extraction optimization of a DFIG-based wind turbine. The proposed control strategy combines an MPPT using a high gain observer and second-order sliding mode for the DFIG control. This strategy presents attractive features such as chattering-free behavior, finite reaching time, robustness and unmodeled dynamics (generator a...

  14. Possibilities for Automatic Control of Hydro-Mechanical Transmission and Birotating Electric Machine

    Directory of Open Access Journals (Sweden)

    V. V. Mikhailov

    2014-01-01

    Full Text Available The paper presents mathematical models and results of virtual investigations pertaining to the selected motion parameters of a mobile machine equipped with hydro mechanical and modernized transmissions. The machine has been tested in similar technological cycles and it has been equipped with a universal automatic control system. Changes in structure and type of power transmission have been obtained with the help of a control algorithm including an extra reversible electric machine which is switched in at some operational modes.Implementation of the proposed  concept makes it possible to obtain and check the improved C-code of the control system and enhance operational parameters of the transmission and machine efficiency, reduce slippage and tire wear while using braking energy for its later beneficial use which is usually considered as a consumable element.

  15. Automatic weight determination in nonlinear model predictive control of wind turbines using swarm optimization technique

    Science.gov (United States)

    Tofighi, Elham; Mahdizadeh, Amin

    2016-09-01

    This paper addresses the problem of automatic tuning of weighting coefficients for the nonlinear model predictive control (NMPC) of wind turbines. The choice of weighting coefficients in NMPC is critical due to their explicit impact on efficiency of the wind turbine control. Classically, these weights are selected based on intuitive understanding of the system dynamics and control objectives. The empirical methods, however, may not yield optimal solutions especially when the number of parameters to be tuned and the nonlinearity of the system increase. In this paper, the problem of determining weighting coefficients for the cost function of the NMPC controller is formulated as a two-level optimization process in which the upper- level PSO-based optimization computes the weighting coefficients for the lower-level NMPC controller which generates control signals for the wind turbine. The proposed method is implemented to tune the weighting coefficients of a NMPC controller which drives the NREL 5-MW wind turbine. The results are compared with similar simulations for a manually tuned NMPC controller. Comparison verify the improved performance of the controller for weights computed with the PSO-based technique.

  16. Automatic Method for Controlling the Iodine Adsorption Number in Carbon Black Oil Furnaces

    Directory of Open Access Journals (Sweden)

    Zečević, N.

    2008-12-01

    Full Text Available There are numerous of different inlet process factors in carbon black oil furnaces which must be continuously and automatically adjusted, due to stable quality of final product. The most important six inlet process factors in carbon black oil-furnaces are:1. volume flow of process air for combustion2. temperature of process air for combustion3. volume flow of natural gas for insurance the necessary heat for thermal reaction of conversionthe hydrocarbon oil feedstock in oil-furnace carbon black4. mass flow rate of hydrocarbon oil feedstock5. type and quantity of additive for adjustment the structure of oil-furnace carbon black6. quantity and position of the quench water for cooling the reaction of oil-furnace carbon black.The control of oil-furnace carbon black adsorption capacity is made with mass flow rate of hydrocarbon feedstock, which is the most important inlet process factor. Oil-furnace carbon black adsorption capacity in industrial process is determined with laboratory analyze of iodine adsorption number. It is shown continuously and automatically method for controlling iodine adsorption number in carbon black oil-furnaces to get as much as possible efficient control of adsorption capacity. In the proposed method it can be seen the correlation between qualitatively-quantitatively composition of the process tail gasses in the production of oil-furnace carbon black and relationship between air for combustion and hydrocarbon feedstock. It is shown that the ratio between air for combustion and hydrocarbon oil feedstock is depended of adsorption capacity summarized by iodine adsorption number, regarding to BMCI index of hydrocarbon oil feedstock.The mentioned correlation can be seen through the figures from 1. to 4. From the whole composition of the process tail gasses the best correlation for continuously and automatically control of iodine adsorption number is show the volume fraction of methane. The volume fraction of methane in the

  17. Flight tests of the total automatic flight control system (Tafcos) concept on a DHC-6 Twin Otter aircraft

    Science.gov (United States)

    Wehrend, W. R., Jr.; Meyer, G.

    1980-01-01

    Flight control systems capable of handling the complex operational requirements of the STOL and VTOL aircraft designs as well as designs using active control concepts are considered. Emphasis is placed on the total automatic flight control system (TACOS) (TAFCOS). Flight test results which verified the performance of the system concept are presented.

  18. Lasing oscillation condition and group delay control in gain-assisted plasmon-induced transparency

    CERN Document Server

    Deng, Zi-Lan; Wang, He-Zhou; Cheng, S H; Li, Jensen

    2012-01-01

    A gain-assisted plasmonic waveguide with two detuned resonators is investigated in the plasmon-induced transparency window. Phase map is employed to study power transmittance and group delay for varying gain coefficients and frequency detunings of the two resonators. The gain coefficient for lasing oscillation condition is analytically shown to vary quadratically with the frequency detuning. In the amplification regime below the lasing threshold, the spectrum implies not only large group delay, but also high transmittance and narrow linewidth. This is in contrast to those in the loss-compensation regime and the passive case in which there always exists a trade-off between the linewidth and the peak transmittance.

  19. GSM Web-Based Centralized Remote Wireless Automatic Controlling and Monitoring of Aquafeeder

    Science.gov (United States)

    Wong, C. L.; Idris, A.; Hasan, Z.

    2016-03-01

    This project is about producing a prototype to feed fishes at fish ponds of remote location with the use of GSM mobile phone. An automatic fish feeder is an electric device that has been designed to give out the right amount of pellets at the designed time. In this project, the automatic feeder designed consists of photovoltaic solar cells that are used to generate electricity and storing it into batteries. Solar charge controllers can be used to determine the rate of which current is drawn and added from the batteries. GSM cellular communication is used to allow user to control from a distance. Commands or instructions are sent to the operating system which in return runs the servomotor and blower by blowing certain amount of fish pallets into the pond to feed the fishes. The duration of the feeding processes is fixed by the user, hence the amount of fish food pallets released are precisely the same for each time. This technology is especially useful for fish farmers where they can remotely feed their fishes.

  20. Controllable optical response by modifying the gain and loss of a mechanical resonator and cavity mode in an optomechanical system

    Science.gov (United States)

    Liu, Yu-Long; Wu, Rebing; Zhang, Jing; Özdemir, Şahin Kaya; Yang, Lan; Nori, Franco; Liu, Yu-xi

    2017-01-01

    We theoretically study a strongly driven optomechanical system which consists of a passive optical cavity and an active mechanical resonator. When the optomechanical coupling strength is varied, phase transitions, which are similar to those observed in PT -symmetric systems, are observed. We show that the optical transmission can be controlled by changing the gain of the mechanical resonator and loss of the optical cavity mode. Especially, we find that (i) for balanced gain and loss, optical amplification and absorption can be tuned by changing the optomechanical coupling strength through a control field; (ii) for unbalanced gain and loss, even with a tiny mechanical gain, both optomechanically induced transparency and anomalous dispersion can be observed around a critical point, which exhibits an ultralong group delay. The time delay τ can be optimized by regulating the optomechanical coupling strength through the control field, and it can be improved up to several orders of magnitude (τ ˜2 ms ) compared to that of conventional optomechanical systems (τ ˜1 μ s ). The presence of mechanical gain makes the group delay more robust to environmental perturbations. Our proposal provides a powerful platform to control light transport using a PT -symmetric-like optomechanical system.

  1. Dynamic Sliding Mode Evolution PWM Controller for a Novel High-Gain Interleaved DC-DC Converter in PV System

    Directory of Open Access Journals (Sweden)

    Taizhou Bei

    2014-01-01

    Full Text Available Considering the disadvantages of the traditional high-gain DC-DC converter such as big size, high voltage stress of switches, and large input current ripple, a novel high-gain interleaved boost converter with coupled-inductor and switched-capacitor was proposed correspondingly and the operation principle together with the steady-state analysis of this converter was also described. Besides, a new control approach-dynamic sliding mode evolution PWM controller (DSME PWM for the novel topological converter based on both dynamic evolution and sliding mode control was also presented. From the simulation results and experimental validation the proposed converter can fulfill high-gain boost, low ripple of both the input current and the output voltage. Furthermore, MPPT technique can be also achieved in a short time by simulation. The efficiency and stability of the converter proposed in this paper can be improved.

  2. Design and evaluation of automatic control for human/liquid cooling garment thermal interaction

    Science.gov (United States)

    Nyberg, Karen Lujean

    An automatic control system was designed and developed to control the thermal comfort of an astronaut wearing a liquid cooling garment (LCG). Experimental trials were run with test subjects performing arm cranking exercise in an environmental chamber. The thermal control algorithm incorporates the use of carbon dioxide production as a measure of metabolic rate to initiate the control response and mean body temperature, as a function of ear canal and skin temperatures, to provide feedback of the human thermal state to the controller. Nine test subjects each completed three, ninety-minute tests in three different environmental temperatures. Subjective comfort levels were obtained from the subjects throughout each test. Evaluation of subjective comfort level and quantitative energy storage indicates good performance of the controller in maintaining thermal neutrality for the subject over a wide range of environmental and transient metabolic states. The Wissler human thermoregulation model was utilized in the control design process and was used to further analyze the experimental results following testing. Subsequent application of the model allowed evaluation of additional protocols for which the LCG thermal controller may be used in the future.

  3. Exercise Training and Weight Gain in Obese Pregnant Women: A Randomized Controlled Trial (ETIP Trial.

    Directory of Open Access Journals (Sweden)

    Kirsti Krohn Garnæs

    2016-07-01

    Full Text Available The effectiveness of exercise training for preventing excessive gestational weight gain (GWG and gestational diabetes mellitus (GDM is still uncertain. As maternal obesity is associated with both GWG and GDM, there is a special need to assess whether prenatal exercise training programs provided to obese women reduce the risk of adverse pregnancy outcomes. Our primary aim was to assess whether regular supervised exercise training in pregnancy could reduce GWG in women with prepregnancy overweight/obesity. Secondary aims were to examine the effects of exercise in pregnancy on 30 outcomes including GDM incidence, blood pressure, blood measurements, skinfold thickness, and body composition.This was a single-center study where we randomized (1:1 91 pregnant women with a prepregnancy body mass index (BMI ≥ 28 kg/m2 to exercise training (n = 46 or control (standard maternity care (n = 45. Assessments were done at baseline (pregnancy week 12-18 and in late pregnancy (week 34-37, as well as at delivery. The exercise group was offered thrice weekly supervised sessions of 35 min of moderate intensity endurance exercise and 25 min of strength training. Seventeen women were lost to follow-up (eight in the exercise group and nine in the control group. Our primary endpoint was GWG from baseline testing to delivery. The principal analyses were done as intention-to-treat analyses, with supplementary per protocol analyses where we assessed outcomes in the women who adhered to the exercise program (n = 19 compared to the control group. Mean GWG from baseline to delivery was 10.5 kg in the exercise group and 9.2 kg in the control group, with a mean difference of 0.92 kg (95% CI -1.35, 3.18; p = 0.43. Among the 30 secondary outcomes in late pregnancy, an apparent reduction was recorded in the incidence of GDM (2009 WHO definition in the exercise group (2 cases; 6.1% compared to the control group (9 cases; 27.3%, with an odds ratio of 0.1 (95% CI 0.02, 0.95; p = 0

  4. Enhancement in the gain recovery of a semiconductor optical amplifier by device temperature control

    Indian Academy of Sciences (India)

    YOGESH KUMAR; M R SHENOY

    2016-12-01

    We present a numerical investigation on the temperature dependence of gain recovery, of a semiconductor optical amplifier (SOA). It is shown that the decrease in temperature significantly speed-up the gain recovery of the SOA. Under typical operating conditions, a 20 K reduction in temperature of the SOA results in a decrease of 150 ps in the gain recovery time. A comparative estimation of device temperature and assisted-light power requirements for enhancing the gain recovery has also been carried out. It is found that, a decrease of 8 K in the temperature of the SOA, is as effective in enhancing the gain recovery as injection of 25 dBm assistedlight power in the counter-propagating mode. Our study shows that under moderate current biasing conditions, temperature reduction is a better and convenient option to speed-up the gain recovery of an SOA, than the use of external assisted-light injection, which requires an additional laser source and wavelength division multiplexing(WDM) components for coupling and de-coupling, leading to insertion losses in the communication channel.

  5. Gain self-scheduled H∞ control for morphing aircraft in the wing transition process based on an LPV model

    Institute of Scientific and Technical Information of China (English)

    Yue Ting; Wang Lixin; Ai Junqiang

    2013-01-01

    This article investigates gain self-scheduled H∞ robust control system design for a tailless folding-wing morphing aircraft in the wing shape varying process.During the wing morphing phase,the aircraft's dynamic response will be governed by time-varying aerodynamic forces and moments.Nonlinear dynamic equations of the morphing aircraft are linearized by using Jacobian linearization approach,and a linear parameter varying (LPV) model of the morphing aircraft in wing folding is obtained.A multi-loop controller for the morphing aircraft is formulated to guarantee stability for the wing shape transition process.The proposed controller uses a set of inner-loop gains to provide stability using classical techniques,whereas a gain self-scheduled H∞ outer-loop controller is devised to guarantee a specific level of robust stability and performance for the time-varying dynamics.The closed-loop simulations show that speed and altitude vary slightly during the whole wing folding process,and they converge rapidly after the process ends.This proves that the gain self-scheduled H∞ robust controller can guarantee a satisfactory dynamic performance for the morphing aircraft during the whole wing shape transition process.Finally,the flight control system's robustness for the wing folding process is verified according to uncertainties of the aerodynamic parameters in the nonlinear model.

  6. Development of an Automatic Frequency Control (AFC) System for RF Electron Linear Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Sungsu; Kim, Yujong; Lee, Byeong-No; Joo, Youngwoo; Lee, Soo Min; Lee, Byung Cheol; Cha, Hyungki [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Park, Hyung Dal [Radiation Technology eXcellence, Daejeon (Korea, Republic of); Lee, Seung Hyun [Sungkyunkwan University, Suwon (Korea, Republic of)

    2015-10-15

    In this paper, the design, fabrication, and RF power test of the AFC system for the X-band linac are presented. The main function of the AFC system is automatically matching of the resonance frequency of the accelerating structure and the RF frequency of the magnetron. For the frequency tuning, a fine tuning of 10 kHz is possible by rotating the tuning shaft with a rotation of 0.72 degree per pulse. Therefore, the frequency deviation is about 0.01%, and almost full RF power (2.1 MW) transmission was obtained because the reflected power is minimized. The Radiation Equipment Research Division of the Korea Atomic Energy Research Institute has been developing and upgrading a medical/industrial X-band RF electron linear accelerators. The medical compact RF electron linear accelerator consists of an electron gun, an acceleration tube (accelerating structure), two solenoid magnets, two steering magnets, a magnetron, modulator, an automatic frequency control (AFC) system, and an X-ray generating target. The accelerating structure of the component is composed of oxygen-free high-conductivity copper (OFHC). Therefore, the volume of the structure, hence, its resonance frequency can easily be changeable if the ambient temperature and pressure are changed. If the RF frequency of the 9300 MHz magnetron and the resonance frequency of accelerating structure are not matched, performance of the structure can be degraded. An AFC system is automatically matched with the RF frequency of the magnetron and resonance frequency of the accelerating structure, which obtained a high output power and reliable accelerator operation.

  7. Effects of gain-scheduling methods in a classical wind turbine controller on wind turbine aeroservoelastic modes and loads

    DEFF Research Database (Denmark)

    Tibaldi, Carlo; Henriksen, Lars Christian; Hansen, Morten Hartvig

    2014-01-01

    The eects of dierent gain-scheduling methods for a classical wind turbine controller, operating in full load region, on the wind turbine aeroservoelastic modes and loads are investigated in this work. The dierent techniques are derived looking at the physical problem to take into account the chan......The eects of dierent gain-scheduling methods for a classical wind turbine controller, operating in full load region, on the wind turbine aeroservoelastic modes and loads are investigated in this work. The dierent techniques are derived looking at the physical problem to take into account...

  8. Embedded Wireless Based Communications and Security Application for Oilfield for Automatic Controlling

    Directory of Open Access Journals (Sweden)

    Ganesh V Padole

    2011-07-01

    Full Text Available The site of oil-well is distributed dispersedly, but distribution area is wide. Oil exhauster continuous working for 24 hours. As the problem of petroleum being stolen, transmission line being stolen, and transformer being stolen exists which requires the strong secures management system. With Consideration of the objective condition restriction of geographical environment, the implementation of safe management for oilfield is very difficult. We overcome these difficulties, which comes from geographical environment. The cost is not only high if the fiber cable would be lay between working station in the several tens of square kilometers, but also need to put into a lot of human and material resources with line maintenance and guard against theft. It is a perfect scheme that remote wireless monitoring and control system is established. The system is required to manage the data received from the various site and providing the security by managing and providing automatic controlling structure.

  9. The alternate wire-feed control in the automatic CO2 arc welding

    Institute of Scientific and Technical Information of China (English)

    卢亚静; 胡绳荪; 易小林; 单平

    2004-01-01

    In the automatic CO2 arc welding, the alteration of the vertical distance between the welding torch and the workpiece has a strong effect on the welding parameters such as welding current and voltage, with the result that the appearance and quality of weld are not steady. To weaken the influence of the distance alteration, a method is put forward in the paper. The method is that the alternate wire-feed control is used for compensating the welding current. On the basis of theoretical analysis, a static numerical model for alternate wire-feed control is established. The experiments show that the model-based regulation of the wire feed rate can compensate the welding current and ensure the appearance of weld. When the alteration of vertical distance between the torch and the workpiece is greater, not only is the wire feed rate regulated, but the output voltage of the power source is adjusted to ensure the appearance and quality of weld.

  10. Availability verification of information for human system interface in automatic SG level control using activity diagram

    Energy Technology Data Exchange (ETDEWEB)

    Nuraslinda, Anuar; Kim, Dong Young; Kim, Jong Hyun [KEPCO International Nuclear Graduate School, Uljugun (Korea, Republic of)

    2012-10-15

    Steam Generator (SG) level control system in OPR 1000 is one of representative automatic systems that falls under the Supervisory Control level in Endsley's taxonomy. Supervisory control of automated systems is classified as a form of out of the loop (OOTL) performance due to passive involvement in the systems operation, which could lead to loss of situation awareness (SA). There was a reported event, which was caused by inadequate human automation communication that contributed to an unexpected reactor trip in July 2005. A high SG level trip occurred in Yeonggwang (YGN) Unit 6 Nuclear Power Plant (NPP) due to human operator failure to recognize the need to change the control mode of the economizer valve controller (EVC) to manual mode during swap over (the transition from low power mode to high power mode) after the loss of offsite power (LOOP) event was recovered. This paper models the human system interaction in NPP SG level control system using Unified Modeling Language (UML) Activity Diagram. Then, it identifies the missing information for operators in the OPR1000 Main Control Room (MCR) and suggests some means of improving the human system interaction.

  11. Improvement of Hydraulic Edge Position Control System by Proportion Sliding Mode of Self-tuning Switching Gain

    Directory of Open Access Journals (Sweden)

    Jin Baoquan

    2012-11-01

    Full Text Available Aiming at the problem of tracking performance degradation of hydraulic EPC system caused by time-varying inertia parameters, nonlinear and external disturbances, the proportion sliding mode control of fuzzy self-tuning gain was proposed. The EPC system state space model on deviation parameters was established and the main feedback sliding mode switching algorithm was designed. The fuzzy method was used to dynamically adjust the proportion sliding mode switching gain by product of the switching function and its derivative state and to adaptive compensate for the uncertainty of the system. At the same time to ensure the effectiveness of the design strategy, the controller model and physical model worked together to simulate the actual conditions. The fixed switching gain switch was, respectively greater and smaller and compared with the fuzzy self-tuning gain, in which the latter achieves a fast and coordinated control of chattering. The results show that after comprehensive consideration all interference the system is stable, fast response, high accuracy and to solve chattering problem caused by the traditional large switching gain of proportion sliding mode.

  12. Optical performance of a PDMS tunable lens with automatically controlled applied stress

    Science.gov (United States)

    Cruz-Felix, Angel S.; Santiago-Alvarado, Agustín.; Hernández-Méndez, Arturo; Reyes-Pérez, Emilio R.; Tepichín-Rodriguez, Eduardo

    2016-09-01

    The advances in the field of adaptive optics and in the fabrication of tunable optical components capable to automatically modify their physical features are of great interest in areas like machine vision, imaging systems, ophthalmology, etc. Such components like tunable lenses are used to reduce the overall size of optical setups like in small camera systems and even to imitate some biological functions made by the human eye. In this direction, in the last years we have been working in the development and fabrication of PDMS-made tunable lenses and in the design of special mechanical mounting systems to manipulate them. A PDMS-made tunable lens was previously designed by us, following the scheme reported by Navarro et al. in 1985, in order to mimic the accommodation process made by the crystalline lens of the human eye. The design included a simulation of the application of radial stress onto the lens and it was shown that the effective focal length was indeed changed. In this work we show the fabrication process of this particular tunable lens and an optimized mechanism that is able to automatically change the curvature of both surfaces of the lens by the application of controlled stress. We also show results of a study and analysis of aberrations performed to the Solid Elastic Lens (SEL).

  13. Cardiovascular Automatic Feedback Control Instrument for Rescuing Critical Patients With Abnormal Blood Pressure

    Institute of Scientific and Technical Information of China (English)

    Ge Yuzhi; Wu Zhiting; Sheng Guotai; Li Gang

    2006-01-01

    Objectives Most medical instruments are designed for diagnosis purpose but very few for clinical treatment. Our research aim is to design and develop a cardiovascular automatic feedback control instrument (CAFCI) for rescuing the critical patients with abnormal blood pressure.Methods The CAFCI was designed on the basis of abundant clinical experiences and on successful mathematic modeling of our experimental data. The blood pressure, pulmonary capillary wedge pressure,and rates of heart beat were measured and inputted into a computer and drugs were chosen by a doctor through a user-friendly interface with the computer.The responses to medication were rapidly acquired and feed back to the computer by automatic detection system in a close-loop system. The data were refreshed every 7.5 sec in order to regulate the speed and dosage of the medications that were given. Results The experimental results with ten dogs showed that the CAFCI system took samples promptly and accurately so that the targeted blood pressure could be reached reliably based on our input parameters and our designing requirements. Conclusions Since the dependability and accuracy of the CAFCI system are much superior to that of the traditional method, its clinical application to rescue the critical patient warrants evaluation in the future.

  14. Hardware simulation of automatic braking system based on fuzzy logic control

    Directory of Open Access Journals (Sweden)

    Noor Cholis Basjaruddin

    2016-07-01

    Full Text Available In certain situations, a moving or stationary object can be a barrier for a vehicle. People and vehicles crossing could potentially get hit by a vehicle. Objects around roads as sidewalks, road separator, power poles, and railroad gates are also a potential source of danger when the driver is inattentive in driving the vehicle. A device that can help the driver to brake automatically is known as Automatic Braking System (ABS. ABS is a part of the Advanced Driver Assistance Systems (ADAS, which is a device designed to assist the driver in driving the process. This device was developed to reduce human error that is a major cause of traffic accidents. This paper presents the design of ABS based on fuzzy logic which is simulated in hardware by using a remote control car. The inputs of fuzzy logic are the speed and distance of the object in front of the vehicle, while the output of fuzzy logic is the intensity of braking. The test results on the three variations of speed: slow-speed, medium-speed, and high-speed shows that the design of ABS can work according to design.

  15. Stabilization Algorithms for Automatic Control of the Trajectory Movement of Quadcopter

    Directory of Open Access Journals (Sweden)

    KeKe Gen

    2015-01-01

    Full Text Available The article considers an automatic quadcopter routing task. The quadcopter is an unmanned aerial vehicle (UAV, which has four engines. Currently, such already widely used vehicles are controlled, mainly, from the operator’s control panel. A relevant task is to develop a quadcopter control system that enables an autonomous flight. The aim of this paper is to study the possibility for solving this problem using an algorithm of the stabilization and trajectory control.A mathematical model of the quadrocopter is the fairly complicated non-linear system, which can be obtained by using the Matlab Simulink and Universal Mechanism software systems simultaneously. Comparison of the simulation results in two software packages, i.e. Matlab wherein the nonlinear system of equations is modeled and UM wherein the flight path and other parameters are calculated according to transmitted forces and moments may prove correctness of the model used.Synthesis of controllers for the orientation and stabilization subsystem and trajectory control subsystem, is performed on traditional principles, in particular using the PID controllers and method based on Lyapunov functions known in the literature as "backstepping." The most appropriate controls are selected by comparing the simulation results. Responses to the stepped impacts and to tracking the given paths have been simulated. It has been found that the flight path of a quadcopter almost coincides with designated routing, changes of coordinates for the quadcopter mass center of two controllers under comparison are almost the same, but a deviation range of the angular position for the controller backstepping is much smaller than that of for the PID controller.

  16. Continuous higher-order sliding mode control with time-varying gain for a class of uncertain nonlinear systems.

    Science.gov (United States)

    Han, Yaozhen; Liu, Xiangjie

    2016-05-01

    This paper presents a continuous higher-order sliding mode (HOSM) control scheme with time-varying gain for a class of uncertain nonlinear systems. The proposed controller is derived from the concept of geometric homogeneity and super-twisting algorithm, and includes two parts, the first part of which achieves smooth finite time stabilization of pure integrator chains. The second part conquers the twice differentiable uncertainty and realizes system robustness by employing super-twisting algorithm. Particularly, time-varying switching control gain is constructed to reduce the switching control action magnitude to the minimum possible value while keeping the property of finite time convergence. Examples concerning the perturbed triple integrator chains and excitation control for single-machine infinite bus power system are simulated respectively to demonstrate the effectiveness and applicability of the proposed approach.

  17. New results on the robust stability of PID controllers with gain and phase margins for UFOPTD processes.

    Science.gov (United States)

    Jin, Q B; Liu, Q; Huang, B

    2016-03-01

    This paper considers the problem of determining all the robust PID (proportional-integral-derivative) controllers in terms of the gain and phase margins (GPM) for open-loop unstable first order plus time delay (UFOPTD) processes. It is the first time that the feasible ranges of the GPM specifications provided by a PID controller are given for UFOPTD processes. A gain and phase margin tester is used to modify the original model, and the ranges of the margin specifications are derived such that the modified model can be stabilized by a stabilizing PID controller based on Hermite-Biehlers Theorem. Furthermore, we obtain all the controllers satisfying a given margin specification. Simulation studies show how to use the results to design a robust PID controller.

  18. A Simulink Library of cryogenic components to automatically generate control schemes for large Cryorefrigerators

    Science.gov (United States)

    Bonne, François; Alamir, Mazen; Hoa, Christine; Bonnay, Patrick; Bon-Mardion, Michel; Monteiro, Lionel

    2015-12-01

    In this article, we present a new Simulink library of cryogenics components (such as valve, phase separator, mixer, heat exchanger...) to assemble to generate model-based control schemes. Every component is described by its algebraic or differential equation and can be assembled with others to build the dynamical model of a complete refrigerator or the model of a subpart of it. The obtained model can be used to automatically design advanced model based control scheme. It also can be used to design a model based PI controller. Advanced control schemes aim to replace classical user experience designed approaches usually based on many independent PI controllers. This is particularly useful in the case where cryoplants are submitted to large pulsed thermal loads, expected to take place in future fusion reactors such as those expected in the cryogenic cooling systems of the International Thermonuclear Experimental Reactor (ITER) or the Japan Torus-60 Super Advanced Fusion Experiment (JT- 60SA). The paper gives the example of the generation of the dynamical model of the 400W@1.8K refrigerator and shows how to build a Constrained Model Predictive Control for it. Based on the scheme, experimental results will be given. This work is being supported by the French national research agency (ANR) through the ANR-13-SEED-0005 CRYOGREEN program.

  19. Automatic control of finite element models for temperature-controlled radiofrequency ablation

    Directory of Open Access Journals (Sweden)

    Haemmerich Dieter

    2005-07-01

    Full Text Available Abstract Background The finite element method (FEM has been used to simulate cardiac and hepatic radiofrequency (RF ablation. The FEM allows modeling of complex geometries that cannot be solved by analytical methods or finite difference models. In both hepatic and cardiac RF ablation a common control mode is temperature-controlled mode. Commercial FEM packages don't support automating temperature control. Most researchers manually control the applied power by trial and error to keep the tip temperature of the electrodes constant. Methods We implemented a PI controller in a control program written in C++. The program checks the tip temperature after each step and controls the applied voltage to keep temperature constant. We created a closed loop system consisting of a FEM model and the software controlling the applied voltage. The control parameters for the controller were optimized using a closed loop system simulation. Results We present results of a temperature controlled 3-D FEM model of a RITA model 30 electrode. The control software effectively controlled applied voltage in the FEM model to obtain, and keep electrodes at target temperature of 100°C. The closed loop system simulation output closely correlated with the FEM model, and allowed us to optimize control parameters. Discussion The closed loop control of the FEM model allowed us to implement temperature controlled RF ablation with minimal user input.

  20. An analytical method for PID controller tuning with specified gain and phase margins for integral plus time delay processes.

    Science.gov (United States)

    Hu, Wuhua; Xiao, Gaoxi; Li, Xiumin

    2011-04-01

    In this paper, an analytical method is proposed for proportional-integral/proportional-derivative/proportional-integral-derivative (PI/PD/PID) controller tuning with specified gain and phase margins (GPMs) for integral plus time delay (IPTD) processes. Explicit formulas are also obtained for estimating the GPMs resulting from given PI/PD/PID controllers. The proposed method indicates a general form of the PID parameters and unifies a large number of existing rules as PI/PD/PID controller tuning with various GPM specifications. The GPMs realized by existing PID tuning rules are computed and documented as a reference for control engineers to tune the PID controllers.

  1. Control of transient gain absorption via tunneling and incoherent pumping in triple quantum dots

    Science.gov (United States)

    Tian, Si-Cong; Zhang, Xiao-Jun; Wan, Ren-Gang; Wang, Li-Jie; Shu, Shi-Li; Wang, Tao; Lu, Ze-Feng; Sun, Fang-Yuan; Tong, Cun-Zhu

    2017-01-01

    The transient gain-absorption properties of the probe field in vertical triple quantum dots assisted by double tunneling and incoherent pumping are investigated. With a proper intensity value and detuning of the second tunneling, the transient gain in triple quantum dots with incoherent pumping can be completely eliminated. In addition, the incoherent pumping affects both the amplitude of the transient absorption and the steady-state value. The dependence of transient behaviors on other parameters, such as the radiative decay rate and the pure dephasing decay rate of the quantum dots, is also discussed. The scheme may have important applications in quantum information networks and communication.

  2. A computer program to automatically control the multi leaf collimator; Un programa informatico para el control automatico del colimador multilamina

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Galiano, P.; Crelgo Alonso, D.; Gonzalez Sancho, J. M.; Fernandez Garcia, J.; Vivanco Parellada, J.

    2012-07-01

    A computer program to automatically analyze strip test images for MLC leaf positioning quality assurance was developed and assessed. The program is fed with raw individual segment images in DICOM format supplied by the accelerator software and it automatically carries out all the steps in the leaf positioning quality control test (image merging, image analysis, storing and reporting). A comprehensive description of the software, that allows a relatively easy implementation, is shown. To check the performance of the program, a series of test fields with intentionally introduced errors were used. The obtained Measurement uncertainty of any individual leaf position was lower than 0.15 mm with gantry at 0 degree centigrade. At another gantry angles (90 degree centigrade, 180 degree centigrade and 270 degree centigrade) the dispersion of the measurements was larger, specially towards the external positions of the leafs, probably due to a slight rotation of the EPID caused by gravity. That reduces the useful area of the MLC to control when gantry angles different from 0 degree centigrade are used. In conclusion, this technique is fast enough to be carried out in a daily basis being also very precise and reliable. (Author)

  3. A flexible and high-performance bidirectional optical amplifier with all optical gain control using ASE noise path through multi-port circulators

    Institute of Scientific and Technical Information of China (English)

    An Vu Tran; Chang-Joon Chae; Rodney S. Tucker

    2003-01-01

    We report a flexible all-optical gain controlled bidirectional optical amplifier. The device achieves constant gain and low noise figure over a large input power range. Moreover, the device removes Rayleigh backscattered light and amplifier noise.

  4. Piloted Simulation Evaluation of a Model-Predictive Automatic Recovery System to Prevent Vehicle Loss of Control on Approach

    Science.gov (United States)

    Litt, Jonathan S.; Liu, Yuan; Sowers, Thomas S.; Owen, A. Karl; Guo, Ten-Huei

    2014-01-01

    This paper describes a model-predictive automatic recovery system for aircraft on the verge of a loss-of-control situation. The system determines when it must intervene to prevent an imminent accident, resulting from a poor approach. It estimates the altitude loss that would result from a go-around maneuver at the current flight condition. If the loss is projected to violate a minimum altitude threshold, the maneuver is automatically triggered. The system deactivates to allow landing once several criteria are met. Piloted flight simulator evaluation showed the system to provide effective envelope protection during extremely unsafe landing attempts. The results demonstrate how flight and propulsion control can be integrated to recover control of the vehicle automatically and prevent a potential catastrophe.

  5. Controller Design and Analysis of Spacecraft Automatic Levelling and Equalizing Hoist Device based on Hanging Point Adjustment

    Directory of Open Access Journals (Sweden)

    Tang Laiying

    2016-01-01

    Full Text Available Spacecraft Automatic Levelling and Equalizing Hoist Device (SALEHD is a kind of hoisting device developed for eccentric spacecraft level-adjusting, based on hanging point adjustment by utilizing XY-workbench. To make the device automatically adjust the spacecraft to be levelling, the controller for SALEHD was designed in this paper. Through geometry and mechanics analysis for SALEHD and the spacecraft, the mathematical model of the controller is established. And then, the link of adaptive control and the link of variable structure control were added into the controller to adapt the unknown parameter and eliminate the interference of support vehicle. The stability of the controller was analysed, through constructing Lyapunov energy function. It was proved that the controller system is asymptotically stable, and converged to origin that is equilibrium point. So the controller can be applied in SALEHD availably and safely.

  6. Slow Dynamics Model of Compressed Air Energy Storage and Battery Storage Technologies for Automatic Generation Control

    Energy Technology Data Exchange (ETDEWEB)

    Krishnan, Venkat; Das, Trishna

    2016-05-01

    Increasing variable generation penetration and the consequent increase in short-term variability makes energy storage technologies look attractive, especially in the ancillary market for providing frequency regulation services. This paper presents slow dynamics model for compressed air energy storage and battery storage technologies that can be used in automatic generation control studies to assess the system frequency response and quantify the benefits from storage technologies in providing regulation service. The paper also represents the slow dynamics model of the power system integrated with storage technologies in a complete state space form. The storage technologies have been integrated to the IEEE 24 bus system with single area, and a comparative study of various solution strategies including transmission enhancement and combustion turbine have been performed in terms of generation cycling and frequency response performance metrics.

  7. Regenerative braking control strategy in mild hybrid electric vehicles equipped with automatic manual transmission

    Institute of Scientific and Technical Information of China (English)

    QIN Datong; YE Ming; LIU Zhenjun

    2007-01-01

    The actual regenerative braking force of an integrated starter/generator (ISG),which is varied with desired braking deceleration and vehicle speed,is calculated based on an analysis of the required deceleration,maximum braking force of ISG,engine braking force and state of charge (SOC) of battery.Braking force distribution strategies are presented according to the actual regenerative braking force of ISG.To recover the vehicle's kinetic energy maximally,braking shift rules for a mild hybrid electric vehicle (HEV) equipped with automatic manual transmission (AMT) are brought forward and effects of transmission ratios are considered.A test-bed is built up and regenerative braking tests are carried out.The results show that power recovered by the braking shift rules is more than that recovered by the normal braking control rules.

  8. A Novel, Automatic Quality Control Scheme for Real Time Image Transmission

    Directory of Open Access Journals (Sweden)

    S. Ramachandran

    2002-01-01

    Full Text Available A novel scheme to compute energy on-the-fly and thereby control the quality of the image frames dynamically is presented along with its FPGA implementation. This scheme is suitable for incorporation in image compression systems such as video encoders. In this new scheme, processing is automatically stopped when the desired quality is achieved for the image being processed by using a concept called pruning. Pruning also increases the processing speed by a factor of more than two when compared to the conventional method of processing without pruning. An MPEG-2 encoder implemented using this scheme is capable of processing good quality monochrome and color images of sizes up to 1024 × 768 pixels at the rate of 42 and 28 frames per second, respectively, with a compression ratio of over 17:1. The encoder is also capable of working in the fixed pruning level mode with user programmable features.

  9. An automatic frequency control loop using overlapping DFTs (Discrete Fourier Transforms)

    Science.gov (United States)

    Aguirre, S.

    1988-01-01

    An automatic frequency control (AFC) loop is introduced and analyzed in detail. The new scheme is a generalization of the well known Cross Product AFC loop that uses running overlapping discrete Fourier transforms (DFTs) to create a discriminator curve. Linear analysis is included and supported with computer simulations. The algorithm is tested in a low carrier to noise ratio (CNR) dynamic environment, and the probability of loss of lock is estimated via computer simulations. The algorithm discussed is a suboptimum tracking scheme with a larger frequency error variance compared to an optimum strategy, but offers simplicity of implementation and a very low operating threshold CNR. This technique can be applied during the carrier acquisition and re-acquisition process in the Advanced Receiver.

  10. SIMULATING LOCAL DENSE AREAS USING PMMA TO ASSESS AUTOMATIC EXPOSURE CONTROL IN DIGITAL MAMMOGRAPHY.

    Science.gov (United States)

    Bouwman, R W; Binst, J; Dance, D R; Young, K C; Broeders, M J M; den Heeten, G J; Veldkamp, W J H; Bosmans, H; van Engen, R E

    2016-06-01

    Current digital mammography (DM) X-ray systems are equipped with advanced automatic exposure control (AEC) systems, which determine the exposure factors depending on breast composition. In the supplement of the European guidelines for quality assurance in breast cancer screening and diagnosis, a phantom-based test is included to evaluate the AEC response to local dense areas in terms of signal-to-noise ratio (SNR). This study evaluates the proposed test in terms of SNR and dose for four DM systems. The glandular fraction represented by the local dense area was assessed by analytic calculations. It was found that the proposed test simulates adipose to fully glandular breast compositions in attenuation. The doses associated with the phantoms were found to match well with the patient dose distribution. In conclusion, after some small adaptations, the test is valuable for the assessment of the AEC performance in terms of both SNR and dose.

  11. Development of a parameter optimization technique for the design of automatic control systems

    Science.gov (United States)

    Whitaker, P. H.

    1977-01-01

    Parameter optimization techniques for the design of linear automatic control systems that are applicable to both continuous and digital systems are described. The model performance index is used as the optimization criterion because of the physical insight that can be attached to it. The design emphasis is to start with the simplest system configuration that experience indicates would be practical. Design parameters are specified, and a digital computer program is used to select that set of parameter values which minimizes the performance index. The resulting design is examined, and complexity, through the use of more complex information processing or more feedback paths, is added only if performance fails to meet operational specifications. System performance specifications are assumed to be such that the desired step function time response of the system can be inferred.

  12. Key techniques of automatic gauge control and profile control for aluminium strip and foil

    Institute of Scientific and Technical Information of China (English)

    LI Mou-wei; LIU Hong-fei; WANG Xiang-li; TONG Chao-nan; YIN Feng-fu; BIAN Xin-xiao; ZHANG Lei

    2006-01-01

    Such characteristics of aluminium strip and foil as soft and thin gauge make tension control one of the key techniques for automation gauge control(AGC). To avoid the disadvantage of traditional mathematical control method which is unfitful for nonlinear hysteresis, the technique for tension AGC fuzzy control was developed and thickness deviation more than 3% of product thickness was achieved consequently in 1 350 mm cold rolling mill of aluminium strip and foil. Additionally, because the gauge of aluminium strip and foil is thin, stage-cooling roll method becomes a key technique for profile control. So stage-cooling roll intelligent control method is developed and pre-coated aluminum foil with good profile less than 10 I (the relative differences in elongation of 0.01% ) is produced using the profile control system in 1 400 mm cold rolling mill of aluminium strip and foil.

  13. Design and Analysis of Automatic Car Park System with Capacity Control

    Directory of Open Access Journals (Sweden)

    Musa Mohammed Gujja

    2015-08-01

    Full Text Available :The need for an automatic car park gate system has been in increase in recent times following the economic situation in present days. The circuit is aimed at eliminating manual operation of a car park. It incorporate the use of LM741 op-amp and CD4017 decade counter for controlling the number of vehicle that can have access to the parking premises and the circuit is fixed close to the gate with the sensor tragically located where it can sense the presence of a car. The light dependent resistor (LDR senses both entrance and exit of the cars and this followed the maximum of three cars in the case of this design. As a monitoring and control system, when you comes close to the gate the light dependent resistor senses an incoming car which allows the gate to open automatically and closed when done. This process is same for outgoing cars. This module make use of an optical sensor, whose resistance changes with the intensity of light (Horowitz, 1980 the type use is ORP12 and it has a dark resistance of 10MΩ. When light rays are focused on the light dependent resistor (LDR, the resistance becomes very low (0-500Ω but when the rays are interrupted, the increases to its dark resistance (Huiyu, 2010. The variable resistor is used to vary the sensitivity of the light dependent resistor. It is otherwise called dark activated sensor. For the design two conditions are considered. First, when light rays are focused on the ORP12, and second, when the rays are being interrupted. The counter registers and displays the number of vehicle crossing the gate (both entrance and exit and allows maximum of three cars. Once the maximum is reached, the gate entrance remains closed and inaccessible, until another vehicle leaves the park. The car park system comprises of the sensor unit, trigger circuitry, display unit (switching unit and the power supply unit.

  14. Feeding patterns and performance of cows in controlled cow traffic in automatic milking systems.

    Science.gov (United States)

    Melin, M; Svennersten-Sjaunja, K; Wiktorsson, H

    2005-11-01

    Two groups of dairy cows monitored from 3 to 19 wk postpartum were subjected to 2 different cow traffic routines in an automatic milking system with control gates and an open waiting area. Using different time settings in the control gates, the groups of cows were separated by average milking frequency; cows in the high milking frequency routine had a minimum of 4 h between milkings (MF(4)) and were milked 3.2 +/- 0.1 times daily, whereas cows in the low milking frequency routine had at least 8 h between milkings (MF8) and were milked 2.1 +/- 0.1 times daily. Cows in the 2 groups were switched to the opposite milking frequency control for wk 18 and 19. The increased milking frequency resulted in a higher milk yield of about 9% through 16 wk of early lactation Although the higher milk yield was not significant when measured as energy-corrected milk, significant interactions of milking frequency and study period for milk yield and energy-corrected milk yield were consistent with a yield response when cows were milked more frequently. Meal criteria estimated for each individual cow were used to group feeding visits into meals. During MF4, cows fed in fewer meals per day and had longer meals than during MF8. The control gates were used efficiently, with only a few passages not resulting in actual meals. Although the voluntary meal intervals seemed to be short, the average milking frequency was far below that theoretically possible. This was explained by individual differences in milking frequency and long intervals from when a cow was redirected in a control gate until it arrived in the milking unit. A wide individual range in the voluntary interval between the first and the second meal in the milking cycle suggests that fixed time limits for control gates set on group level have no justifiable biological basis. It was also concluded that primiparous cows were well adapted to the automatic milking system after 2 wk in the barn.

  15. Optimal camera exposure for video surveillance systems by predictive control of shutter speed, aperture, and gain

    Science.gov (United States)

    Torres, Juan; Menéndez, José Manuel

    2015-02-01

    This paper establishes a real-time auto-exposure method to guarantee that surveillance cameras in uncontrolled light conditions take advantage of their whole dynamic range while provide neither under nor overexposed images. State-of-the-art auto-exposure methods base their control on the brightness of the image measured in a limited region where the foreground objects are mostly located. Unlike these methods, the proposed algorithm establishes a set of indicators based on the image histogram that defines its shape and position. Furthermore, the location of the objects to be inspected is likely unknown in surveillance applications. Thus, the whole image is monitored in this approach. To control the camera settings, we defined a parameters function (Ef ) that linearly depends on the shutter speed and the electronic gain; and is inversely proportional to the square of the lens aperture diameter. When the current acquired image is not overexposed, our algorithm computes the value of Ef that would move the histogram to the maximum value that does not overexpose the capture. When the current acquired image is overexposed, it computes the value of Ef that would move the histogram to a value that does not underexpose the capture and remains close to the overexposed region. If the image is under and overexposed, the whole dynamic range of the camera is therefore used, and a default value of the Ef that does not overexpose the capture is selected. This decision follows the idea that to get underexposed images is better than to get overexposed ones, because the noise produced in the lower regions of the histogram can be removed in a post-processing step while the saturated pixels of the higher regions cannot be recovered. The proposed algorithm was tested in a video surveillance camera placed at an outdoor parking lot surrounded by buildings and trees which produce moving shadows in the ground. During the daytime of seven days, the algorithm was running alternatively together

  16. Automatic PID Control Loops Design for Performance Improvement of Cryogenic Turboexpander

    Science.gov (United States)

    Joshi, D. M.; Patel, H. K.; Shah, D. K.

    2015-04-01

    Cryogenics field involves temperature below 123 K which is much less than ambient temperature. In addition, many industrially important physical processes—from fulfilling the needs of National Thermonuclear Fusion programs, superconducting magnets to treatment of cutting tools and preservation of blood cells, require extreme low temperature. The low temperature required for liquefaction of common gases can be obtained by several processes. Liquefaction is the process of cooling or refrigerating a gas to a temperature below its critical temperature so that liquid can be formed at some suitable pressure which is below the critical pressure. Helium liquefier is used for the liquefaction process of helium gas. In general, the Helium Refrigerator/Liquefier (HRL) needs turboexpander as expansion machine to produce cooling effect which is further used for the production of liquid helium. Turboexpanders, a high speed device that is supported on gas bearings, are the most critical component in many helium refrigeration systems. A very minor fault in the operation and manufacturing or impurities in the helium gas can destroy the turboexpander. However, since the performance of expanders is dependent on a number of operating parameters and the relations between them are quite complex, the instrumentation and control system design for turboexpander needs special attention. The inefficiency of manual control leads to the need of designing automatic control loops for turboexpander. Proper design and implementation of the control loops plays an important role in the successful operation of the cryogenic turboexpander. The PID control loops has to be implemented with accurate interlocks and logic to enhance the performance of the cryogenic turboexpander. For different normal and off-normal operations, speeds will be different and hence a proper control method for critical rotational speed avoidance is must. This paper presents the design of PID control loops needed for the

  17. Tuning of PID controller for an automatic regulator voltage system using chaotic optimization approach

    Energy Technology Data Exchange (ETDEWEB)

    Santos Coelho, Leandro dos [Pontifical Catholic University of Parana, PUCPR Industrial and Systems Engineering Graduate Program, LAS/PPGEPS Imaculada Conceicao, 1155, Zip code 80215-901, Curitiba, Parana (Brazil)], E-mail: leandro.coelho@pucpr.br

    2009-02-28

    Despite the popularity, the tuning aspect of proportional-integral-derivative (PID) controllers is a challenge for researchers and plant operators. Various controllers tuning methodologies have been proposed in the literature such as auto-tuning, self-tuning, pattern recognition, artificial intelligence, and optimization methods. Chaotic optimization algorithms as an emergent method of global optimization have attracted much attention in engineering applications. Chaotic optimization algorithms, which have the features of easy implementation, short execution time and robust mechanisms of escaping from local optimum, is a promising tool for engineering applications. In this paper, a tuning method for determining the parameters of PID control for an automatic regulator voltage (AVR) system using a chaotic optimization approach based on Lozi map is proposed. Since chaotic mapping enjoys certainty, ergodicity and the stochastic property, the proposed chaotic optimization introduces chaos mapping using Lozi map chaotic sequences which increases its convergence rate and resulting precision. Simulation results are promising and show the effectiveness of the proposed approach. Numerical simulations based on proposed PID control of an AVR system for nominal system parameters and step reference voltage input demonstrate the good performance of chaotic optimization.

  18. Towards the implementation of e-manufacturing: design of an automatic tea drying control system

    Directory of Open Access Journals (Sweden)

    Mabvuu, Never

    2014-11-01

    Full Text Available Many of the production costs for producing tea are attributable to the process of drying the tea. E-manufacturing can assist companies to reduce these production costs by making crucial information available to decision-makers so that they can make informed decisions. This paper presents an application of e-manufacturing to the design of an automatic tea drying control system. This control system will ensure that the multiple drying parameters such as temperature, dryer-exit tea moisture content, and fuel consumption are maintained at optimal states during the course of the drying of tea. The additional aim of this system is to balance the cost of production and the quality of the final product. Using the Guggenheim-Anderson-De Boer (GAB model, the optimum drying temperature was found to be 100-110°C, while maintaining a dryer-exit tea moisture content of 3 to 3.12 per cent, at a drying rate of 3 per cent per minute. A Barix control application to control the system’s activities, using the web user interface (WUI, was also developed.

  19. Testing a satellite automatic nutation control system. [on synchronous meteorological satellite

    Science.gov (United States)

    Hrasiar, J. A.

    1974-01-01

    Testing of a particular nutation control system for the synchronous meteorological satellite (SMS) is described. The test method and principles are applicable to nutation angle control for other satellites with similar requirements. During its ascent to synchronous orbit, a spacecraft like the SMS spins about its minimum-moment-of-inertia axis. An uncontrolled spacecraft in this state is unstable because torques due to fuel motion increase the nutation angle. However, the SMS is equipped with an automatic nutation control (ANC) system which will keep the nutation angle close to zero. Because correct operation of this system is critical to mission success, it was tested on an air-bearing table. The ANC system was mounted on the three-axis air-bearing table which was scaled to the SMS and equipped with appropriate sensors and thrusters. The table was spun up in an altitude chamber and nutation induced so that table motion simulated spacecraft motion. The ANC system was used to reduce the nutation angle. This dynamic test of the ANC system met all its objectives and provided confidence that the ANC system will control the SMS nutation angle.

  20. Fully automatic control of paraplegic FES pedaling using higher-order sliding mode and fuzzy logic control.

    Science.gov (United States)

    Farhoud, Aidin; Erfanian, Abbas

    2014-05-01

    In this paper, a fully automatic robust control strategy is proposed for control of paraplegic pedaling using functional electrical stimulation (FES). The method is based on higher-order sliding mode (HOSM) control and fuzzy logic control. In FES, the strength of muscle contraction can be altered either by varying the pulse width (PW) or by the pulse amplitude (PA) of the stimulation signal. The proposed control strategy regulates simultaneously both PA and PW (i.e., PA/PW modulation). A HOSM controller is designed for regulating the PW and a fuzzy logic controller for the PA. The proposed control scheme is free-model and does not require any offline training phase and subject-specific information. Simulation studies on a virtual patient and experiments on three paraplegic subjects demonstrate good tracking performance and robustness of the proposed control strategy against muscle fatigue and external disturbances during FES-induced pedaling. The results of simulation studies show that the power and cadence tracking errors are 5.4% and 4.8%, respectively. The experimental results indicate that the proposed controller can improve pedaling system efficacy and increase the endurance of FES pedaling. The average of power tracking error over three paraplegic subjects is 7.4±1.4% using PA/PW modulation, while the tracking error is 10.2±1.2% when PW modulation is used. The subjects could pedal for 15 min with about 4.1% power loss at the end of experiment using proposed control strategy, while the power loss is 14.3% using PW modulation. The controller could adjust the stimulation intensity to compensate the muscle fatigue during long period of FES pedaling.

  1. Central automatic control or distributed occupant control for better indoor environment quality in the future

    DEFF Research Database (Denmark)

    Toftum, Jørn

    2008-01-01

    of adverse symptoms and building related symptoms than the ventilation mode per se. This result indicates that even though the development and application of new indoor environment sensors and HVAC control systems may allow for fully automated IEQ control, such systems should not compromise occupants...... in the degree of perceived control. The database was composed of 1353 responses obtained in 25 buildings of which 15 had mechanical ventilation (997 responses) and 9 had natural ventilation (275 responses). Analysis of occupant responses, after grouping according to categories determined by the degree...... of satisfaction with the perceived control, showed that the degree of control satisfaction, but rarely building category (natural vs. mechanical ventilation), affected the prevalence of adverse perceptions and symptoms. Thus, the degree of control, as perceived by occupants, was more important for the prevalence...

  2. Central automatic control or distributed occupant control for better indoor environment quality in the future

    DEFF Research Database (Denmark)

    Toftum, Jørn

    2010-01-01

    of control, as perceived by occupants, seemed more important for the prevalence of adverse symptoms and building-related symptoms than the ventilation mode per se. This result indicates that even though the development and application of new indoor environment sensors and HVAC control systems may allow...... for fully automated IEQ control, such systems should not compromise occupants' perception of having some degree of control of their indoor environment....... a discrepancy in the degree of perceived control. The database was composed of 1272 responses obtained in 24 buildings of which 15 had mechanical ventilation (997 responses) and 9 had natural ventilation (275 responses). The number of occupant-reported control opportunities was higher in buildings with natural...

  3. Fuzzy Gain Scheduling of PI Controller for Dual Star Induction Machine fed by a Matrix Converter

    OpenAIRE

    B. Meliani; A. Meroufel; H. Khouidmi

    2012-01-01

    The aim of this paper is to present a full digital implementation of a field orientation controlled Double Star induction Machine, and a PI controller is designed to control the speed, the machine is fed by a matrix converter. The advent of vector control technique has partially solved DSIM control problems because they are sensitive to drive parameter variations and performance may deteriorate if conventional controllers are used. Fuzzy logic and neural network Based controllers are consider...

  4. Compensation for secondary uncertainty in electro-hydraulic servo system by gain adaptive sliding mode variable structure control

    Institute of Scientific and Technical Information of China (English)

    ZHANG You-wang; GUI Wei-hua

    2008-01-01

    Based on consideration of the differential relations between the immeasurable variables and measurable variables in electro-hydraulic servo system, adaptive dynamic recurrent fuzzy neural networks(ADRFNNs) were employed to identify the primary uncertainty and the mathematic model of the system was turned into an equivalent linear model with terms of secondary uncertainty. At the same time, gain adaptive sliding mode variable structure control(GASMVSC) was employed to synthesize the control effort. The results show that the unrealization problem caused by some system's immeasurable state variables in traditional fuzzy neural networks(TFNN) taking all state variables as its inputs is overcome. On the other hand, the identification by the ADRFNNs online with high accuracy and the adaptive function of the correction term's gain in the GASMVSC make the system possess strong robustness and improved steady accuracy, and the chattering phenomenon of the control effort is also suppressed effectively.

  5. Coaxial GaAs-AlGaAs core-multishell nanowire lasers with epitaxial gain control

    Energy Technology Data Exchange (ETDEWEB)

    Stettner, T., E-mail: Thomas.Stettner@wsi.tum.de, E-mail: Gregor.Koblmueller@wsi.tum.de, E-mail: Jonathan.Finley@wsi.tum.de; Zimmermann, P.; Loitsch, B.; Regler, A.; Mayer, B.; Winnerl, J.; Matich, S.; Riedl, H.; Kaniber, M.; Abstreiter, G.; Koblmüller, G., E-mail: Thomas.Stettner@wsi.tum.de, E-mail: Gregor.Koblmueller@wsi.tum.de, E-mail: Jonathan.Finley@wsi.tum.de; Finley, J. J., E-mail: Thomas.Stettner@wsi.tum.de, E-mail: Gregor.Koblmueller@wsi.tum.de, E-mail: Jonathan.Finley@wsi.tum.de [Walter Schottky Institut and Physik Department, TU München, Garching 85748 (Germany); Döblinger, M. [Department of Chemistry, Ludwig-Maximilians-Universität München, Munich 81377 (Germany)

    2016-01-04

    We demonstrate the growth and single-mode lasing operation of GaAs-AlGaAs core-multishell nanowires (NW) with radial single and multiple GaAs quantum wells (QWs) as active gain media. When subject to optical pumping lasing emission with distinct s-shaped input-output characteristics, linewidth narrowing and emission energies associated with the confined QWs are observed. Comparing the low temperature performance of QW NW laser structures having 7 coaxial QWs with a nominally identical structure having only a single QW shows that the threshold power density reduces several-fold, down to values as low as ∼2.4 kW/cm{sup 2} for the multiple QW NW laser. This confirms that the individual radial QWs are electronically weakly coupled and that epitaxial design can be used to optimize the gain characteristics of the devices. Temperature-dependent investigations show that lasing prevails up to 300 K, opening promising new avenues for efficient III–V semiconductor NW lasers with embedded low-dimensional gain media.

  6. Rapid Automatized Naming in Children with Dyslexia: Is Inhibitory Control Involved?

    Science.gov (United States)

    Bexkens, Anika; van den Wildenberg, Wery P M; Tijms, Jurgen

    2015-08-01

    Rapid automatized naming (RAN) is widely seen as an important indicator of dyslexia. The nature of the cognitive processes involved in rapid naming is however still a topic of controversy. We hypothesized that in addition to the involvement of phonological processes and processing speed, RAN is a function of inhibition processes, in particular of interference control. A total 86 children with dyslexia and 31 normal readers were recruited. Our results revealed that in addition to phonological processing and processing speed, interference control predicts rapid naming in dyslexia, but in contrast to these other two cognitive processes, inhibition is not significantly associated with their reading and spelling skills. After variance in reading and spelling associated with processing speed, interference control and phonological processing was partialled out, naming speed was no longer consistently associated with the reading and spelling skills of children with dyslexia. Finally, dyslexic children differed from normal readers on naming speed, literacy skills, phonological processing and processing speed, but not on inhibition processes. Both theoretical and clinical interpretations of these results are discussed.

  7. 11th International Federation of Automatic Control (IFAC) Workshop on Time-Delay Systems

    CERN Document Server

    Fridman, Emilia; Sename, Olivier; Dugard, Luc

    2016-01-01

    This book mostly results from a selection of papers presented during the 11th IFAC (International Federation of Automatic Control) Workshop on Time-Delay Systems, which took place in Grenoble, France, February 4 - 6, 2013.  During this event, 37 papers were presented. Taking into account the reviewers' evaluation and the papers' presentation the best papers have been selected and collected into the present volume. The authors of 13 selected papers were invited to participate to this book and provided a more detailed and improved version of the conference paper. To enrich the book, three more chapters have been included from specialists on time-delay systems who presented their work during the 52nd IEEE Conference on Decision and Control, which held in December 10 - 13, 2013, at Florence, Italy. The content of the book is divided into four main parts as follows: Modeling, Stability analysis, Stabilization and control, and Input-delay systems. Focusing on various topics of time-delay systems, this book will be...

  8. Reason's Enemy Is Not Emotion: Engagement of Cognitive Control Networks Explains Biases in Gain/Loss Framing.

    Science.gov (United States)

    Li, Rosa; Smith, David V; Clithero, John A; Venkatraman, Vinod; Carter, R McKell; Huettel, Scott A

    2017-03-29

    In the classic gain/loss framing effect, describing a gamble as a potential gain or loss biases people to make risk-averse or risk-seeking decisions, respectively. The canonical explanation for this effect is that frames differentially modulate emotional processes, which in turn leads to irrational choice behavior. Here, we evaluate the source of framing biases by integrating functional magnetic resonance imaging data from 143 human participants performing a gain/loss framing task with meta-analytic data from >8000 neuroimaging studies. We found that activation during choices consistent with the framing effect were most correlated with activation associated with the resting or default brain, while activation during choices inconsistent with the framing effect was most correlated with the task-engaged brain. Our findings argue against the common interpretation of gain/loss framing as a competition between emotion and control. Instead, our study indicates that this effect results from differential cognitive engagement across decision frames.SIGNIFICANCE STATEMENT The biases frequently exhibited by human decision makers have often been attributed to the presence of emotion. Using a large fMRI sample and analysis of whole-brain networks defined with the meta-analytic tool Neurosynth, we find that neural activity during frame-biased decisions was more significantly associated with default behaviors (and the absence of executive control) than with emotion. These findings point to a role for neuroscience in shaping long-standing psychological theories in decision science.

  9. Preventing weight gain: the baseline weight related behaviors and delivery of a randomized controlled intervention in community based women

    Directory of Open Access Journals (Sweden)

    Teede Helena J

    2009-01-01

    Full Text Available Abstract Background Women aged 25–45 years represent a high risk group for weight gain and those with children are at increased risk because of weight gain associated with pregnancy and subsequent lifestyle change. Average self-reported weight gain is approximately 0.60 kg per year, and weight gain is associated with increased risk of chronic disease. There are barriers to reaching, engaging and delivering lifestyle interventions to prevent weight gain in this population. Methods This study investigated the baseline weight related behaviors and feasibility of recruiting and delivering a low intensity self-management lifestyle intervention to community based women with children in order to prevent weight gain, compared to standard education. The recruitment and delivery of the cluster-randomized controlled intervention was in conjunction with 12 primary (elementary schools. Baseline data collection included demographic, anthropometric, behavioral and biological measures. Results Two hundred and fifty community based women were randomized as clusters to intervention (n = 127 or control (n = 123. Mean age was 40.4 years (SD 4.7 and mean BMI 27.8 kg/m2 (SD 5.6. All components of this intervention were successfully delivered and retention rates were excellent, 97% at 4 months. Nearly all women (90% reported being dissatisfied with their weight and 72% attempted to self-manage their weight. Women were more confident of changing their diet (mean score 3.2 than physical activity (mean score 2.7. This population perceived they were engaging in prevention behaviors, with 71% reporting actively trying to prevent weight gain, yet they consumed a mean of 68 g fat/day (SD30 g and 27 g saturated fat/day (SD12 g representing 32% and 13% of energy respectively. The women had a high rate of dyslipidemia (33% and engaged in an average of 9187 steps/day (SD 3671. Conclusion Delivery of this low intensity intervention to a broad cross-section of community based

  10. Dynamic gain control with a matrix inequality approach to uncertain systems with triangular and non-triangular nonlinearities

    Science.gov (United States)

    Koo, Min-Sung; Choi, Ho-Lim

    2016-04-01

    We consider the global regulation problem of uncertain systems with both triangular and non-triangular nonlinearities. For the global regulation in the presence of non-triangular nonlinearities, we propose a dynamic gain controller designed by using power order conditions and a matrix inequality condition imposed on non-triangular nonlinearities. Compared with the existing results, the proposed control method allows a class of nonlinear systems that have not been treated before. Analysis and examples are given to prove the general applicability of our control method.

  11. On the Control of Automatic Processes: A Parallel Distributed Processing Account of the Stroop Effect.

    Science.gov (United States)

    Cohen, Jonathan D.; And Others

    1990-01-01

    It is proposed that attributes of automatization depend on the strength of a processing pathway, and that strength increases with training. With the Stroop effect as an example, automatic processes are shown through simulation to be continuous and to emerge gradually with practice. (SLD)

  12. 染料生产过程的自动控制%Automatic Control for Dye Production

    Institute of Scientific and Technical Information of China (English)

    马文宝

    2012-01-01

    详细介绍了我国染料工业的发展现状,染料生产过程的综合自动控制水平、生产特点及其控制要求;列举了自动控制的主要内容,常用的控制方案以及控制方案选择的基本原则。最后对自动控制技术的应用前景作了展望,并简述了提高染料生产过程自控水平的重要意义。%The current situation, automatization level, production characteristics and control requirement in dye pro- duction were introduced in detail. The main contents of automatic control, the control scheme commonly used and the bas- ic principles for scheme selection were enumerated. In the end, application prospects of the automatic control technology were predicted, and the significance of improving the automatization level was also given.

  13. A digital-analog hybrid system and its application to the automatic flight control system simulation research

    Science.gov (United States)

    1981-01-01

    The characteristics of a digital-analog hybrid system composed of a DJS-8 digital computer and a HMJ-200 analog computer are described as well as its applications to simulation research for an automatic flight control system. A hybrid computational example is included to illustrate the application.

  14. The N400 and Late Positive Complex (LPC Effects Reflect Controlled Rather than Automatic Mechanisms of Sentence Processing

    Directory of Open Access Journals (Sweden)

    Boris Kotchoubey

    2012-08-01

    Full Text Available This study compared automatic and controlled cognitive processes that underlie event-related potentials (ERPs effects during speech perception. Sentences were presented to French native speakers, and the final word could be congruent or incongruent, and presented at one of four levels of degradation (using a modulation with pink noise: no degradation, mild degradation (2 levels, or strong degradation. We assumed that degradation impairs controlled more than automatic processes. The N400 and Late Positive Complex (LPC effects were defined as the differences between the corresponding wave amplitudes to incongruent words minus congruent words. Under mild degradation, where controlled sentence-level processing could still occur (as indicated by behavioral data, both N400 and LPC effects were delayed and the latter effect was reduced. Under strong degradation, where sentence processing was rather automatic (as indicated by behavioral data, no ERP effect remained. These results suggest that ERP effects elicited in complex contexts, such as sentences, reflect controlled rather than automatic mechanisms of speech processing. These results differ from the results of experiments that used word-pair or word-list paradigms.

  15. An assessment of overall open-loop "gain" of CO2-ventilation feedback control system in hypoxia.

    Science.gov (United States)

    Masuyama, H; Akiyama, S; Honda, Y

    1985-01-01

    Overall open-loop gain of the CO2-ventilation feedback control system in hypoxia (GHCO2) was determined on 8 male and one female healthy subjects. They breathed in a closed circuit, and were subjected to the progressive hypoxia test. This procedure was first conducted without dead space (DS), then with 250, 500, and finally 750 ml DS, consecutively. GHCO2 was calculated by dividing the slope of the CO2 response curve (S) by that of the metabolic hyperbola (SL). GHCO2 was considerably larger than the overall open-loop gain of the O2-ventilation feedback control system (GO2) previously obtained. This was ascribed to the facts that S was larger than the slope of the hypoxia response curve, and that the absolute value of SL in GHCO2 was smaller than that in GO2.

  16. Fuzzy Gain Scheduling of PI Controller for Dual Star Induction Machine fed by a Matrix Converter

    Directory of Open Access Journals (Sweden)

    B. Meliani

    2012-06-01

    Full Text Available The aim of this paper is to present a full digital implementation of a field orientation controlled Double Star induction Machine, and a PI controller is designed to control the speed, the machine is fed by a matrix converter. The advent of vector control technique has partially solved DSIM control problems because they are sensitive to drive parameter variations and performance may deteriorate if conventional controllers are used. Fuzzy logic and neural network Based controllers are considered as potential candidates for such an application. In this paper the fuzzy logic system is used on-line to generate the PI controller parameters. Simulink results for a 4.5 kW six-phase induction machine are presented and analyzed using a matlab environment. Obtained results demonstrated that the proposed control scheme is able to obtain high performances.

  17. Design of an expert system to automatically calibrate impedance control for powered knee prostheses.

    Science.gov (United States)

    Wang, Ding; Liu, Ming; Zhang, Fan; Huang, He

    2013-06-01

    Many currently available powered knee prostheses (PKP) use finite state impedance control to operate a prosthetic knee joint. The desired impedance values were usually manually calibrated with trial-and-error in order to enable near-normal walking pattern. However, such a manual approach is inaccurate, time consuming, and impractical. This paper aimed to design an expert system that can tune the control impedance for powered knee prostheses automatically and quickly. The expert system was designed based on fuzzy logic inference (FLI) to match the desired knee motion and gait timing while walking. The developed system was validated on an able-bodied subject wearing a powered prosthesis. Preliminary experimental results demonstrated that the developed expert system can converge the user's knee profile and gait timing to the desired values within 2 minutes. Additionally, after the auto-tuning procedure, the user produced more symmetrical gait. These preliminary results indicate the promise of the designed expert system for quick and accuracy impedance calibration, which can significantly improve the practical value of powered lower limb prosthesis. Continuous engineering efforts are still needed to determine the calibration objectives and validate the expert system.

  18. A Computer Model of the Evaporator for the Development of an Automatic Control System

    Science.gov (United States)

    Kozin, K. A.; Efremov, E. V.; Kabrysheva, O. P.; Grachev, M. I.

    2016-08-01

    For the implementation of a closed nuclear fuel cycle it is necessary to carry out a series of experimental studies to justify the choice of technology. In addition, the operation of the radiochemical plant is impossible without high-quality automatic control systems. In the technologies of spent nuclear fuel reprocessing, the method of continuous evaporation is often used for a solution conditioning. Therefore, the effective continuous technological process will depend on the operation of the evaporation equipment. Its essential difference from similar devices is a small size. In this paper the method of mathematic simulation is applied for the investigation of one-effect evaporator with an external heating chamber. Detailed modelling is quite difficult because the phase equilibrium dynamics of the evaporation process is not described. Moreover, there is a relationship with the other process units. The results proved that the study subject is a MIMO plant, nonlinear over separate control channels and not selfbalancing. Adequacy was tested using the experimental data obtained at the laboratory evaporation unit.

  19. A 155 Mbps laser diode driver with automatic power and extinction ratio control

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    An integrated laser diode driver (LDD) driving an edge-emitting laser diode was designed and fabricated by 0.35 μm BiCMOS technology. This paper proposes a scheme which combines the automatic power control loop and temperature compensation for modulation current in order to maintain constant extinction ratio and average optical power. To implement temperature compensation for modulation current, a novel circuit which generates a PTAT current by using the injecting base current of a bipolar transistor in saturation region, and alternates the amplifier feedback loop (closed or not) to control the state of the current path is presented. Simulation results showed that programmed by choice of external resistors, the IC can provide modulation current from 5 mA to 85 mA with temperature compensation adjustments and independent bias current from 4 mA to 100 mA. Optical test results showed that clear eye-diagrams can be obtained at 155 Mbps, with the output optical power being nearly constant, and the variation of extinction ratio being lower than 0.7 dB.

  20. Benchmarking of control strategies for ATAD technology: a first approach to the automatic control of sludge treatment systems.

    Science.gov (United States)

    Zambrano, J A; Gil-Martinez, M; Garcia-Sanz, M; Irizar, I

    2009-01-01

    Autothermal Thermophilic Aerobic Digestion (ATAD technology) is a promising alternative to conventional digestion systems. Aeration is a key factor in the performance of these kinds of reactors, in relation to effluent quality and operating costs. At present, the realisation of automatic control in ATADs is in its infancy. Additionally, the lack of robust sensors also makes the control of these processes difficult: only redox potential and temperature sensors are reliable for operation in full-scale plants. Based as it is on the existing simulation protocols for benchmarking of control strategies for wastewater treatment plants (WWTP), this paper presents the definition and implementation of a similar protocol but specifically adapted to the needs of ATAD technology. The implemented simulation protocol has been used to validate two different control strategies for aeration (ST1 and ST2). In comparison to an open-loop operation for the ATAD, simulation results showed that the ST1 strategy was able to save aeration costs of around 2-4%. Unlike ST1, ST2 achieved maximum sludge stabilisation but at the expense of higher aeration costs.

  1. Improved synthetic-heterodyne Michelson interferometer vibrometer using phase and gain control feedback.

    Science.gov (United States)

    Galeti, José Henrique; Kitano, Cláudio; Connelly, Michael J

    2015-12-10

    Synthetic-heterodyne demodulation is a useful technique for dynamic displacement and velocity measurement using interferometric sensors as it can provide an output signal which is immune to interferometric drift. With the advent of cost effective, high-speed real-time signal processing systems and software, processing of the complex signals encountered in interferometry has become more feasible. In conventional synthetic-heterodyne demodulation schemes, to obtain the dynamic displacement or vibration of the object under test requires knowledge of the interferometer visibility and also the argument of two Bessel functions. In this paper, a new synthetic-heterodyne demodulation method is described leading to an expression for the dynamic displacement and velocity of the object under test that is significantly less sensitive to the received optical power. In addition, the application of two independent phase and gain feedback loops is used to compensate for the nonideal gain and phase response of the anti-aliasing filter required for the signal acquisition of the received wideband interferometer signal. The efficacy of the improved system is demonstrated by measuring the displacement sensitivity frequency response and linearity of a Piezoelectric Mirror-Shifter (PMS) over a range of 200 Hz-9 kHz. In addition, the system is used to measure the response of the PMS to triangular and impulse type stimuli. The experimental results show excellent agreement with measurements taken using two independent industry standard calibration methods.

  2. The Impact of Weight Gain on Motivation, Compliance, and Metabolic Control in Patients with Type 2 Diabetes Mellitus

    OpenAIRE

    Pi-Sunyer, F. Xavier

    2009-01-01

    Patients with type 2 diabetes, approximately 85% of whom are overweight or obese, often have an increased incidence of cardiovascular disease (CVD) risk factors such as hypertension and dyslipidemia. Both type 2 diabetes and obesity are independent risk factors for CVD. Unfortunately, many therapies aimed at maintaining and improving glucose control are associated with weight gain. Among the older antidiabetes agents, most, including the insulin secretagogues and sensitizers, can lead to weig...

  3. Weight Gain Prevention among Midlife Women: A Randomized Controlled Trial to Address Needs Related to the Physical and Social Environment

    Directory of Open Access Journals (Sweden)

    Courtney D. Perry

    2016-05-01

    Full Text Available Women tend to gain weight at midlife (40–60 years increasing risk of obesity-related chronic diseases. Within specific eating occasions, needs related to the physical and social environment may result in less healthy eating behavior, which can lead to weight gain over time. The purpose of this study was to determine if a dietitian-delivered nutrition counseling intervention tailored to eating occasion needs could improve diet and prevent weight gain among midlife women over two years. A randomized controlled trial was conducted with healthy midlife women (n = 354 in one U.S. metropolitan area. The intervention group (n = 185 received ten hours of individual nutrition counseling from dietitians over six months, while women in a control group (n = 169 received no counseling. Measured height, weight and waist circumference, and dietary intakes were collected at baseline and every six months over two years. Mixed linear models were used to test for intervention effect on change in outcome variables over time. Dietary intakes of fruit, reduced/low-fat dairy foods and refined grains were significantly improved over time in the intervention compared to control group. However, the intervention had no effect on weight over time (p = 0.48. Nutrition counseling tailored to address eating occasion needs improved self-reported diet but did not significantly affect weight change.

  4. Adaptive Switching Gain for a Discrete-Time Sliding Mode Controller

    NARCIS (Netherlands)

    Monsees, G.; Scherpen, J.M.A.

    2000-01-01

    Sliding Mode Control is a well-known technique capable of making the closed loop system robust with respect to certain kinds of parameter variations and unmodeled dynamics. The sliding mode control law consists of the linear control part which is based on the model knowledge and the discontinuous co

  5. Automatic Optimization of Focal Point Position in CO2 Laser Welding with Neural Network in A Focus Control System

    DEFF Research Database (Denmark)

    Gong, Hui; Olsen, Flemming Ove

    CO2 lasers are increasingly being utilized for quality welding in production. Considering the high cost of equipment, the start-up time and the set-up time should be minimized. Ideally the parameters should be set up and optimized more or less automatically. In this paper a control system...... is designed and built to automatically optimize the focal point position, one of the most important parameters in CO2 laser welding, in order to perform a desired deep/full penetration welding. The control system mainly consists of a multi-axis motion controller - PMAC, a light sensor - Photo Diode, a data....... The results of the self-learning focus control system show that the neural network is capable of optimizing the focal point position with good accuracy in CW CO2 laser welding....

  6. Switching Controller Design for a Class of Markovian Jump Nonlinear Systems Using Stochastic Small-Gain Theorem

    Directory of Open Access Journals (Sweden)

    Jin Zhu

    2009-01-01

    Full Text Available Switching controller design for a class of Markovian jump nonlinear systems with unmodeled dynamics is considered in this paper. Based on the differential equation and infinitesimal generator of jump systems, the concept of Jump Input-to-State practical Stability (JISpS in probability and stochastic Lyapunov stability criterion are put forward. By using backsetpping technology and stochastic small-gain theorem, a switching controller is proposed which ensures JISpS in probability for the jump nonlinear system. A simulation example illustrates the validity of this design.

  7. Evaluation of the use of automatic exposure control and automatic tube potential selection in low-dose cerebrospinal fluid shunt head CT

    Energy Technology Data Exchange (ETDEWEB)

    Wallace, Adam N.; Bagade, Swapnil; Chatterjee, Arindam; Hicks, Brandon; McKinstry, Robert C. [Barnes Jewish Hospital, Mallinckrodt Institute of Radiology, St. Louis, MO (United States); Washington University School of Medicine, St. Louis, MO (United States); Vyhmeister, Ross [Washington University School of Medicine, St. Louis, MO (United States); Ramirez-Giraldo, Juan Carlos [Siemens Healthcare, Malvern, PA (United States)

    2015-03-17

    Cerebrospinal fluid shunts are primarily used for the treatment of hydrocephalus. Shunt complications may necessitate multiple non-contrast head CT scans resulting in potentially high levels of radiation dose starting at an early age. A new head CT protocol using automatic exposure control and automated tube potential selection has been implemented at our institution to reduce radiation exposure. The purpose of this study was to evaluate the reduction in radiation dose achieved by this protocol compared with a protocol with fixed parameters. A retrospective sample of 60 non-contrast head CT scans assessing for cerebrospinal fluid shunt malfunction was identified, 30 of which were performed with each protocol. The radiation doses of the two protocols were compared using the volume CT dose index and dose length product. The diagnostic acceptability and quality of each scan were evaluated by three independent readers. The new protocol lowered the average volume CT dose index from 15.2 to 9.2 mGy representing a 39 % reduction (P < 0.01; 95 % CI 35-44 %) and lowered the dose length product from 259.5 to 151.2 mGy/cm representing a 42 % reduction (P < 0.01; 95 % CI 34-50 %). The new protocol produced diagnostically acceptable scans with comparable image quality to the fixed parameter protocol. A pediatric shunt non-contrast head CT protocol using automatic exposure control and automated tube potential selection reduced patient radiation dose compared with a fixed parameter protocol while producing diagnostic images of comparable quality. (orig.)

  8. Modeling and simulation of the generation automatic control of electric power systems; Modelado y simulacion del control automatico de generacion de sistemas electricos de potencia

    Energy Technology Data Exchange (ETDEWEB)

    Caballero Ortiz, Ezequiel

    2002-12-01

    This work is devoted to the analysis of the Automatic Control of Electrical Systems Generation of power, as of the information that generates the loop with Load-Frequency Control and the Automatic Voltage Regulator loop. To accomplish the analysis, the control classical theory and feedback control systems concepts are applied. Thus also, the modern theory concepts are employed. The studies are accomplished in the digital computer through the MATLAB program and the available simulation technique in the SIMULINK tool. In this thesis the theoretical and physical concepts of the automatic control of generation are established; dividing it in load frequency control and automatic voltage regulator loops. The mathematical models of the two control loops are established. Later, the models of the elements are interconnected in order to integrate the loop with load frequency control and the digital simulation of the system is carried out. In first instance, the function of the primary control in are - machine, area - multi machine and multi area - multi machine power systems, is analyzed. Then, the automatic control of generation of the area and multi area power systems is studied. The economic dispatch concept is established and with this plan the power system multi area is simulated, there in after the energy exchange among areas in stationary stage is studied. The mathematical models of the component elements of the control loop of the automatic voltage regulator are interconnected. Data according to the nature of each component are generated and their behavior is simulated to analyze the system response. The two control loops are interconnected and a simulation is carry out with data generated previously, examining the performance of the automatic control of generation and the interaction between the two control loops. Finally, the Poles Positioning and the Optimum Control techniques of the modern control theory are applied to the automatic control of an area generation

  9. Doses under automatic exposure control (AEC) for direct digital radiographic (DDR) X-ray systems.

    Science.gov (United States)

    Bowden, Louise; Faulkner, Ronan; Clancy, Conor; Gallagher, Aoife; Devine, Mark; Gorman, Dermot; O'Reilly, Geraldine; Dowling, Anita

    2011-09-01

    Current guidelines quote tolerances for automatic exposure control (AEC) device performance for X-ray systems as 'Baseline ± X %'. However, in the situation where a baseline figure has not yet been achieved, as in the case of commissioning assessments, this tolerance is not relevant. The purpose of this work is to provide mean doses for direct digital radiography (DDR) X-ray system, operating in AEC, against which comparisons can be made. Dose measurements have been recorded under AEC operation on 29 DDR detectors from three different manufacturers. Two different testing protocols were examined: (1) water equivalent phantoms in front of the DDR detector and (2) aluminium block at the tube head. The average patient exit dose, using the aluminium block was 4.6 μGy with the antiscatter grid in place and 4.0 μGy with the grid removed. Using the water phantoms, the average dose was measured at 17.1 μGy with the antiscatter grid in place and 5.4 μGy with grid removed. Based on these results, it is clear that different testing configurations significantly impact on the measured dose.

  10. Autonomous monitoring of control hardware to predict off-normal conditions using NIF automatic alignment systems

    Energy Technology Data Exchange (ETDEWEB)

    Awwal, Abdul A.S., E-mail: awwal1@llnl.gov [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Wilhelmsen, Karl; Leach, Richard R.; Miller-Kamm, Vicki; Burkhart, Scott; Lowe-Webb, Roger; Cohen, Simon [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer An automatic alignment system was developed to process images of the laser beams. Black-Right-Pointing-Pointer System uses processing to adjust a series of control loops until alignment criteria are satisfied. Black-Right-Pointing-Pointer Monitored conditions are compared against nominal values with an off-normal alert. Black-Right-Pointing-Pointer Automated health monitoring system trends off-normals with a large image history. - Abstract: The National Ignition Facility (NIF) is a high power laser system capable of supporting high-energy-density experimentation as a user facility for the next 30 years. In order to maximize the facility availability, preventive maintenance enhancements are being introduced into the system. An example of such an enhancement is a camera-based health monitoring system, integrated into the automated alignment system, which provides an opportunity to monitor trends in measurements such as average beam intensity, size of the beam, and pixel saturation. The monitoring system will generate alerts based on observed trends in measurements to allow scheduled pro-active maintenance before routine off-normal detection stops system operations requiring unscheduled intervention.

  11. TU-CD-207-11: Patient-Driven Automatic Exposure Control for Dedicated Breast CT

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, A; Gazi, P [Biomedical Engineering Graduate Group, University of California Davis, Davis, CA (United States); Department of Radiology, UC Davis Medical Center, Sacramento, CA (United States); Seibert, J; Boone, J [Department of Radiology, UC Davis Medical Center, Sacramento, CA (United States); Department of Biomedical Engineering, University of California Davis, Davis, CA (United States)

    2015-06-15

    Purpose: To implement automatic exposure control (AEC) in dedicated breast CT (bCT) on a patient-specific basis using only the pre-scan scout views. Methods: Using a large cohort (N=153) of bCT data sets, the breast effective diameter (D) and width in orthogonal planes (Wa,Wb) were calculated from the reconstructed bCT image and pre-scan scout views, respectively. D, Wa, and Wb were measured at the breast center-of-mass (COM), making use of the known geometry of our bCT system. These data were then fit to a second-order polynomial “D=F(Wa,Wb)” in a least squares sense in order to provide a functional form for determining the breast diameter. The coefficient of determination (R{sup 2}) and mean percent error between the measured breast diameter and fit breast diameter were used to evaluate the overall robustness of the polynomial fit. Lastly, previously-reported bCT technique factors derived from Monte Carlo simulations were used to determine the tube current required for each breast diameter in order to match two-view mammographic dose levels. Results: F(Wa,Wb) provided fitted breast diameters in agreement with the measured breast diameters resulting in R{sup 2} values ranging from 0.908 to 0.929 and mean percent errors ranging from 3.2% to 3.7%. For all 153 bCT data sets used in this study, the fitted breast diameters ranged from 7.9 cm to 15.7 cm corresponding to tube current values ranging from 0.6 mA to 4.9 mA in order to deliver the same dose as two-view mammography in a 50% glandular breast with a 80 kV x-ray beam and 16.6 second scan time. Conclusion: The present work provides a robust framework for AEC in dedicated bCT using only the width measurements derived from the two orthogonal pre-scan scout views. Future work will investigate how these automatically chosen exposure levels affect the quality of the reconstructed image.

  12. Gaining Control and Predictability of Software-Intensive Systems Development and Sustainment

    Science.gov (United States)

    2015-02-04

    this would be a major design driver for the software architect (Naegle & Petross, 2007). Primary Software Acquisition Problem Areas Addressed The...control and produces significantly more predictability in the program management realm. The research conclusions and recommendations are designed to...provide more control and predictability to software-intensive systems development. Due to the TOC and architectural design focus, system sustainability

  13. Adaptive switching gain for a discrete-time sliding mode controller

    NARCIS (Netherlands)

    Monsees, G.; Scherpen, J.M.A.

    2002-01-01

    Sliding mode control is a well-known technique capable of making the closed loop system robust with respect to certain kinds of parameter variations and unmodelled dynamics. The sliding mode control law consists of a continuous component which is based on the model knowledge and discontinuous compon

  14. Automatic Control of the Reciprocating Compressor%往复压缩机的自动控制

    Institute of Scientific and Technical Information of China (English)

    赵庆林

    2013-01-01

    There are mainly logic control and sequence control in automatic control of the reciprocating compressor, and the difficulty is automatic sequence control for the compressor start or stop.Taking a fresh hydrogen compressor as an example,this paper introduces the configuration of an instrument control system for the fresh hydrogen compressor,the realization of the one button controls for full automatic compressor start or stop operation.The good application effect is received.%往复压缩机的自动控制主要体现在逻辑控制和顺序控制2个方面,其中自动开停机顺序控制是此类压缩机的控制难点.本文以某装置新氢压缩机的自动控制为例,介绍该压缩机的仪表控制系统配置集成、一键式全自动开停机顺序控制方案的实现策略,以及所取得的应用效果.

  15. An assessment of overall "gain" of the O2-feedback control system with and without external dead space breathing.

    Science.gov (United States)

    Masuyama, H; Hayashi, F; Honda, Y

    1983-01-01

    Overall gain of the O2-ventilation feedback control system (GO2) was determined in 9 male and one female healthy subjects. GO2 progressively increased with decreasing end-tidal PO2 (PETO2). This value did not exceed the overall gain of the CO2-ventilation feedback system (GCO2) even at a PETO2 level of 40 mmHg, suggesting that hypoxic stimulation did not become predominant in the present experimental condition. With addition of 250 ml of external dead space, PETO2 decrement (delta PETO2 X actual) was experimentally observed. The delta PETO2 X actual thus obtained was found to be in good agreement with the PETO2 decrement deduced from GO2 (delta PETO2 X expected). This result was similar to that found in the PETCO2 change previously seen in normoxia.

  16. Stress- and diet-induced fat gain is controlled by NPY in catecholaminergic neurons.

    Science.gov (United States)

    Zhang, Lei; Lee, I-Chieh J; Enriquez, Rondaldo F; Lau, Jackie; Vähätalo, Laura H; Baldock, Paul A; Savontaus, Eriika; Herzog, Herbert

    2014-08-01

    Neuropeptide Y (NPY) and noradrenaline are commonly co-expressed in sympathetic neurons. Both are key regulators of energy homeostasis and critical for stress-coping. However, little is known about the specific function of NPY in the catecholaminergic system in these regulations. Here we show that mice with NPY expression only in the noradrenergic and adrenergic cells of the catecholaminergic system (catNPY) exhibited exacerbated diet-induced obesity, lower body and brown adipose tissue temperatures compared to WT and NPY(-/-) mice under a HFD. Furthermore, chronic stress increased adiposity and serum corticosterone level in WT but not NPY(-/-) mice. Re-introducing NPY specifically to the catecholaminergic system in catNPY mice restored stress responsiveness associated with increased respiratory exchange ratio and decreased liver pACC to tACC ratio. These results demonstrate catecholaminergic NPY signalling is critical in mediating diet- and chronic stress-induced fat gain via effects on diet-induced thermogenesis and stress-induced increases in corticosterone levels and lipogenic capacity.

  17. Storage for free: a surprising property of a simple gain-control model of motion aftereffects.

    Science.gov (United States)

    van de Grind, Wim A; van der Smagt, Maarten J; Verstraten, Frans A J

    2004-01-01

    If a motion aftereffect (MAE) for given adaptation conditions has a duration T s, and the eyes are closed after adaptation during a waiting period tw=T s before testing, an unexpected MAE of a 'residual' duration TrT s is experienced. This effect is called 'storage' and it is often quantified by a storage factor sigma=TrT/T, which can reach values up to about 0.7-0.8. The phenomenon and its name have invited explanations in terms of inhibition of recovery during darkness. We present a model based on the opposite idea, that an effective test stimulus quickens recovery relative to darkness or other ineffective test stimuli. The model is worked out in mathematical detail and proves to explain 'storage' data from the literature, on the static MAE (sMAE: an MAE experienced for static test stimuli). We also present results of a psychophysical experiment with moving random pixel arrays, quantifying storage phenomena both for the sMAE and the dynamic MAE (dMAE: an MAE experienced for a random dynamic noise test stimulus). Storage factors for the dMAE are lower than for the sMAE. Our model also gives an excellent description of these new data on storage of the dMAE. The term 'storage' might therefore be a misnomer. If an effective test stimulus influences all direction tuned motion sensors indiscriminately and thus speeds up equalization of gains, one gets the storage phenomenon for free.

  18. A Dynamic Visualization Environment For The Design And Evaluation Of Automatic Vehicle Control Systems

    OpenAIRE

    Xu, Z.

    1995-01-01

    This document presents Dynamic Visualization, a project associated with the California PATH Program. The objective of the project is to develop a software which can animate automated highways, visualize the dynamics of automatic vehicles, and help the design and evaluation of automatic vehicle systems. This report summarizes the accomplishments of the project, describes the functions of the developed software, and provides an explanation of how to use the software.

  19. Application of a New Membership Function in Nonlinear Fuzzy PID Controllers with Variable Gains

    Directory of Open Access Journals (Sweden)

    Xuda Zhang

    2014-01-01

    Full Text Available This paper proposes a nonlinear fuzzy PID control algorithm, whose membership function (MF is adjustable, is universal, and has a wide adjustable range. Appling this function to fuzzy control theory will increase system’s tunability. The continuity of this function is proved. This method was employed in the simulation and HIL experiments. Effectiveness and feasibility of this function are demonstrated in the results.

  20. An integrated approach to the design of an aircraft gain scheduled controller

    OpenAIRE

    Berglund, Erik

    1995-01-01

    This thesis addresses the problem of integrated design of the aircraft plant parameters and of the corresponding feedback controller. The plant parameters are typically the sizes of the control surfaces or other aerodynamical surfaces of the aircraft. The approach is to rewrite the aircraft dynamic requirements as linear matrix inequalities (LMI's) and to optimize a linear cost function associated with aircraft plant parameters, while meeting the LMI constraints. An algorithm using Matlab and...

  1. Gain Scheduling Control of Gas Turbine Engines: Stability by Computing a Single Quadratic Lyapunov Function

    Science.gov (United States)

    2013-06-01

    STABILITY BY COMPUTING A SINGLE QUADRATIC LYAPUNOV FUNCTION Mehrdad Pakmehr∗ PhD Candidate Decision and Control Laboratory (DCL) School of Aerospace...linearization and linear matrix inequality (LMI) techniques. Using convex optimization tools, a single quadratic Lyapunov function is computed for multiple...Scheduling Control of Gas Turbine Engines: Stability by Computing a Single Quadratic Lyapunov Function 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c

  2. Simple adaptive pH control in bioreactors using gain-scheduling methods.

    Science.gov (United States)

    Gnoth, S; Kuprijanov, A; Simutis, R; Lübbert, A

    2010-01-01

    A simple well-performing adaptive control technique for pH control in fermentations of recombinant protein production processes is described and its design procedure is explained. First, the entire control algorithm was simulated and parameterized. Afterwards it was tested in real cultivation processes. The results show that this simple technique leads to significant reductions in the fluctuations of the pH values in microbial cultures at a minimum of expenditures. The signal-to-noise ratio and thus the information captured by the pH signal were increased by about an order of magnitude. This leads to a substantial improvement in the noise of many other process signals that are used to monitor and control the process. For instance, respiratory off-gas data of CO(2) and its derived carbon dioxide production rate signals from the cultures carry much less noise as compared to those values obtained with conventional pH control. Detailed process analysis revealed that even very small pH jumps of 0.03 values during the fermentation were shown to result in pronounced deflections in CO(2)-volume fraction of 8% (peak to peak). The proposed controller, maintaining the pH within the interval of 0.01 around the setpoint, reduces the noise considerably.

  3. LMI-based gain scheduled controller synthesis for a class of linear parameter varying systems

    DEFF Research Database (Denmark)

    Bendtsen, Jan Dimon; Anderson, Brian; Lanzon, Alexander

    2006-01-01

    This paper presents a novel method for constructing controllers for a class of single-input multiple-output (SIMO) linear parameter varying (LPV) systems. This class of systems encompasses many physical systems, in particular systems where individual components vary with time, and is therefore...... the parameters are varying, with the degree of stability related directly to a bound on the average rate of allowable parameter variations. Thus, if knowledge of the parameter variations is available, the conservativeness of the design can be kept at a minimum. The construction of the controller is formulated...

  4. On a small-gain approach to distributed event-triggered control

    NARCIS (Netherlands)

    De Persis, Claudio; Sailer, R.; Wirth, F.

    2011-01-01

    We consider large-scale systems stabilized by distributed controllers, which communicate over a limited shared medium. In this context it is of interest to reduce the communication load. An approach in this direction is eventtriggered sampling, which attempts only to send “relevant” data. In order t

  5. Sliding mode attitude control with L 2-gain performance and vibration reduction of flexible spacecraft with actuator dynamics

    Science.gov (United States)

    Hu, Qinglei

    2010-09-01

    This paper presents a dual-stage control system design method for the rotational maneuver control and vibration stabilization of a flexible spacecraft. In this design approach, the sub-systems of attitude control and vibration suppression are designed separately using the low order model. Based on the sliding mode control (SMC) theory, a discontinuous attitude control law in the form of the input voltage of the reaction wheel is derived to control the orientation of the spacecraft, incorporating the L 2-gain performance criterion constraint. The resulting closed-loop system is proven to be uniformly ultimately bounded stability and the effect of the external disturbance on both attitude quaternion and angular velocity can be attenuated to the prescribed level as well. In addition, an adaptive version of the control law is designed for adapting the unknown upper bounds of the lumped disturbance such that the limitation of knowing the bound of the disturbance in advance is released. For actively suppressing the induced vibration, strain rate feedback control method is also investigated by using piezoelectric materials as additional sensors and actuators bonded on the surface of the flexible appendages. Numerical simulations are performed to show that rotational maneuver and vibration suppression are accomplished in spite of the presence of disturbance and uncertainty.

  6. Actively phase-controlled coupling between plasmonic waveguides via in-between gain-assisted nanoresonator: nanoscale optical logic gates.

    Science.gov (United States)

    Ho, Kum-Song; Han, Yong-Ha; Ri, Chol-Song; Im, Song-Jin

    2016-08-15

    The development of nanoscale optical logic gates has attracted immense attention due to increasing demand for ultrahigh-speed and energy-efficient optical computing and data processing, however, suffers from the difficulty in precise control of phase difference of the two optical signals. We propose a novel conception of nanoscale optical logic gates based on actively phase-controlled coupling between two plasmonic waveguides via an in-between gain-assisted nanoresonator. Precise control of phase difference between the two plasmonic signals can be performed by manipulating pumping rate at an appropriate frequency detuning, enabling a high contrast between the output logic states "1" and "0." Without modification of the structural parameters, different logic functions can be provided. This active nanoscale optical logic device is expected to be quite energy-efficient with ideally low energy consumption on the order of 0.1 fJ/bit. Analytical calculations and numerical experiments demonstrate the validity of the proposed concept.

  7. Modeling and distributed gain scheduling strategy for load frequency control in smart grids with communication topology changes.

    Science.gov (United States)

    Liu, Shichao; Liu, Xiaoping P; El Saddik, Abdulmotaleb

    2014-03-01

    In this paper, we investigate the modeling and distributed control problems for the load frequency control (LFC) in a smart grid. In contrast with existing works, we consider more practical and real scenarios, where the communication topology of the smart grid changes because of either link failures or packet losses. These topology changes are modeled as a time-varying communication topology matrix. By using this matrix, a new closed-loop power system model is proposed to integrate the communication topology changes into the dynamics of a physical power system. The globally asymptotical stability of this closed-loop power system is analyzed. A distributed gain scheduling LFC strategy is proposed to compensate for the potential degradation of dynamic performance (mean square errors of state vectors) of the power system under communication topology changes. In comparison to conventional centralized control approaches, the proposed method can improve the robustness of the smart grid to the variation of the communication network as well as to reduce computation load. Simulation results show that the proposed distributed gain scheduling approach is capable to improve the robustness of the smart grid to communication topology changes.

  8. High-gain adaptive regulator for a string equation with uncertain harmonic disturbance under boundary output feedback control

    Institute of Scientific and Technical Information of China (English)

    Baozhu GUO; Wei GUO

    2003-01-01

    This paper considers the boundary stabilization and parameter estimation of a one-dimensional wave equation in the case when one end is fixed and control and harmonic disturbance with uncertain amplitude are input at another end. A high-gain adaptive regulator is designed in terms of measured collocated end velocity. The existence and uniqueness of the classical solution of the closed-loop system is proven. It is shown that the state of the system approaches the standstill as time goes to infitv and meanwhile, the estimated parameter converges to the unknown parameter.

  9. A routine quality assurance test for CT automatic exposure control systems.

    Science.gov (United States)

    Iball, Gareth R; Moore, Alexis C; Crawford, Elizabeth J

    2016-07-08

    The study purpose was to develop and validate a quality assurance test for CT automatic exposure control (AEC) systems based on a set of nested polymethylmethacrylate CTDI phantoms. The test phantom was created by offsetting the 16 cm head phantom within the 32 cm body annulus, thus creating a three part phantom. This was scanned at all acceptance, routine, and some nonroutine quality assurance visits over a period of 45 months, resulting in 115 separate AEC tests on scanners from four manufacturers. For each scan the longitudinal mA modulation pattern was generated and measurements of image noise were made in two annular regions of interest. The scanner displayed CTDIvol and DLP were also recorded. The impact of a range of AEC configurations on dose and image quality were assessed at acceptance testing. For systems that were tested more than once, the percentage of CTDIvol values exceeding 5%, 10%, and 15% deviation from baseline was 23.4%, 12.6%, and 8.1% respectively. Similarly, for the image noise data, deviations greater than 2%, 5%, and 10% from baseline were 26.5%, 5.9%, and 2%, respectively. The majority of CTDIvol and noise deviations greater than 15% and 5%, respectively, could be explained by incorrect phantom setup or protocol selection. Barring these results, CTDIvol deviations of greater than 15% from baseline were found in 0.9% of tests and noise deviations greater than 5% from baseline were found in 1% of tests. The phantom was shown to be sensitive to changes in AEC setup, including the use of 3D, longitudinal or rotational tube current modulation. This test methodology allows for continuing performance assessment of CT AEC systems, and we recommend that this test should become part of routine CT quality assurance programs. Tolerances of ± 15% for CTDIvol and ± 5% for image noise relative to baseline values should be used.

  10. An investigation of automatic exposure control calibration for chest imaging with a computed radiography system.

    Science.gov (United States)

    Moore, C S; Wood, T J; Avery, G; Balcam, S; Needler, L; Beavis, A W; Saunderson, J R

    2014-05-07

    The purpose of this study was to examine the use of three physical image quality metrics in the calibration of an automatic exposure control (AEC) device for chest radiography with a computed radiography (CR) imaging system. The metrics assessed were signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and mean effective noise equivalent quanta (eNEQm), all measured using a uniform chest phantom. Subsequent calibration curves were derived to ensure each metric was held constant across the tube voltage range. Each curve was assessed for its clinical appropriateness by generating computer simulated chest images with correct detector air kermas for each tube voltage, and grading these against reference images which were reconstructed at detector air kermas correct for the constant detector dose indicator (DDI) curve currently programmed into the AEC device. All simulated chest images contained clinically realistic projected anatomy and anatomical noise and were scored by experienced image evaluators. Constant DDI and CNR curves do not appear to provide optimized performance across the diagnostic energy range. Conversely, constant eNEQm and SNR do appear to provide optimized performance, with the latter being the preferred calibration metric given as it is easier to measure in practice. Medical physicists may use the SNR image quality metric described here when setting up and optimizing AEC devices for chest radiography CR systems with a degree of confidence that resulting clinical image quality will be adequate for the required clinical task. However, this must be done with close cooperation of expert image evaluators, to ensure appropriate levels of detector air kerma.

  11. Automatic control of pollutant on a shallow river using surface water systems: application to the Ebro River.

    Science.gov (United States)

    Puig, V; Romera, J; Quevedo, J; Sarrate, R; Morales-Hernandez, M; Gonzalez-Sanchis, M; Garcia-Navarro, P

    2014-01-01

    In this paper, the problem of automatic control of pollutant on a shallow river using surface water systems is addressed using a benchmark test case based in the Ebro River. The Ebro River presents flooding episodes in the city of Zaragoza in Spring when snow melts in the Pyrenees. To avoid flooding and high pollutant levels in living areas, some lands outside the city are prepared to be flooded. Going one step further, this paper is focused on the pollutant level control at a certain point downstream of the river under flooding episodes, and several control strategies for that purpose are presented and tested.

  12. An artificial vision-based control system for automatic heliostat positioning offset correction in a central receiver solar power plant

    Energy Technology Data Exchange (ETDEWEB)

    Berenguel, M. [Universidad de Almeria, Dept. de Lenguajes y Computacion, La Canada Almeria (Spain); Rubio, F.R.; Lara, P.J.; Arahal, M.R.; Camacho, E.F.; Lopez, M. [Universidad de Sevilla, Dept. de Ingenieria de Sistemas y Automatica, Sevilla (Spain); Valverde, A. [Plataforma Solar de Almeria (PSA-CIEMAT), Tabernas (Almeria) (Spain)

    2004-07-01

    This paper presents the development of a simplified and automatic heliostat positioning offset correction control system using artificial vision techniques and common CCD devices. The heliostats of a solar power plant reflect solar radiation onto a receiver (in this case, a volumetric receiver) placed at the top of a tower in order to provide a desired energy flux distribution correlated with the coolant flow (in this case air mass flow) through the receiver, usually in an open loop control configuration. There exist error sources that increase the complexity of the control system, some of which are systematic ones, mainly due to tolerances, wrong mirror facets alignment (optical errors), errors due to the approximations made when calculating the solar position, etc., that produce errors (offsets) in the heliostat orientation (aiming point). The approximation adopted in this paper is based on the use of a B/W CCD camera to correct these deviations in an automatic way imitating the same procedure followed by the operators. The obtained images are used to estimate the distance between the sunbeam centroid projected by the heliostats and a target placed on the tower, this distance thus is used for low accuracy offset correction purposes. Basic threshold-based image processing techniques are used for automatic correction. (Author)

  13. Research and Implementation on Control Algorithm in Automatic Control Glue System%自动控胶系统控制算法的研究与实现

    Institute of Scientific and Technical Information of China (English)

    何斌

    2012-01-01

    自动控胶是胶订机的一个重要工艺过程.自动控胶是以自动控制理论为指导,自动控制技术为手段,实现控胶工艺过程自动化的技术.合理有效的控制算法是实现这一技术的基础,这里讨论的是怎样按照控制工艺过程和控制器件的连接、位置和时序关系建立算法模型.并根据叠加原理,将复杂算法分解成单一算法,逐一实现之.%Automatic Control Glue is an important process in binding machine. Automatic Control Glue is a technology to achieve con-trolled process automation, which is guided by the theory of automatic control and based on automatic control technology. Reasonable and ef-fective control algorithms are the basis for achieving this technical, here is discussing how to build an algorithm model according to technolog-ical process control and control devices, location and timing of connection relationships. According to the principle of superposition,complex algorithms are composed into a single algorithm, and realize them one by one, This control principles and methods have been applied to TB500CM6A elliptic binding package, and have had effective control.

  14. Automatic controller to water plants Acionador automático para irrigar plantas

    Directory of Open Access Journals (Sweden)

    Leonardo Oliveira Medici

    2010-12-01

    Full Text Available Despite the massive demand of water for plant irrigation, there are few devices being used in the automation of this process in agriculture. This work evaluates a simple controller to water plants automatically that can be set up with low cost commercial materials, which are large-scale produced. This controller is composed by a ceramic capsule used in common domestic water filters; a plastic tube around 1.5 m long, and a pressostate used in domestic washing machines. The capsule and the pressostate are connected through the tube so that all parts are filled with water. The ceramic capsule is the sensor of the controller and has to be placed into the plant substrate. The pressostate has to be placed below the sensor and the lower it is, the higher is the water tension to start the irrigation, since the lower is the pressostate the higher is the water column above it and, therefore, the higher is the tension inside the ceramic cup to pull up the water column. The controller was evaluated in the control of drip irrigation for small containers filled with commercial organic substrate or soil. Linear regressions explained the relationship between the position of pressostate and the maximum water tension in the commercial substrate (p A despeito da enorme demanda por água na irrigação de plantas, existem poucos aparelhos para automação deste processo sendo usados na agricultura. Avaliou-se um acionador automático para irrigação, o qual pode ser confeccionado com materiais comerciais de baixo custo, pois são produzidos em larga escala. Este acionador é composto por uma cápsula cerâmica usada em filtros de água domésticos; um tubo plástico com cerca de um metro e meio de comprimento e um pressostato de máquinas de lavar roupas domésticas. A cápsula e o pressostato são conectados pelo tubo de forma que todo o espaço interno seja preenchido com água. A cápsula é o sensor do acionador e deve ser posicionada dentro do substrato das

  15. A Sigma-Delta ADC with Decimation and Gain Control Function for a Bluetooth Receiver in 130 nm Digital CMOS

    Directory of Open Access Journals (Sweden)

    Koh Jinseok

    2006-01-01

    Full Text Available We present a discrete-time second-order multibit sigma-delta ADC that filters and decimates by two the input data samples. At the same time it provides gain control function in its input sampling stage. A 4-tap FIR switched capacitor (SC architecture was chosen for antialiasing filtering. The decimation-by-two function is realized using divided-by-two clock signals in the antialiasing filter. Antialiasing, gain control, and sampling functions are merged in the sampling network using SC techniques. This compact architecture allows operating the preceding blocks at twice the ADC's clock frequency, thus improving the noise performance of the wireless receiver channel and relaxing settling requirements of the analog building blocks. The presented approach has been validated and incorporated in a commercial single-chip Bluetooth radio realized in a 1.5 V 130 nm digital CMOS process. The measured antialiasing filtering shows better than 75 dB suppression at the folding frequency band edge. A 67 dB dynamic range was measured with a sampling frequency of 37.5MHz.

  16. [Grazing systems, rotenone and parasites control in crossbred calves: effect on live weight gain and on parasites burdens].

    Science.gov (United States)

    Catto, João B; Bianchin, Ivo; Santurio, Jânio M; Feijó, Gelson L D; Kichel, Armindo N; Silva, José M da

    2009-01-01

    Practices for endo and ectoparasite control in beef cattle were evaluated in two independent experiments. First, the effects of rotenone on Rhipicephalus (Boophilus) microplus ticks were evaluated in vitro and in experimentally infected calves. In the second trial, the effects of grazing systems associated with endo and ectoparasite treatments on parasite burden and weight gain of naturally parasited animals were evaluated. Rotenone showed acaricide action on larvae and engorged ticks during in vitro tests and on larvae in experimentally infected calves. Three treatments with endectocide decreased (P parasited by horn fly, tick and larvae of Dermatobia hominis and the group treated with rotenone were significantly less parasited by horn fly in relation to control. Animals under rotational grazing showed significantly higher EPG than those under continuous grazing. Three treatments with endectocide in the dry season plus three acaricide treatments with fipronil in the raining season reduced EPG, tick, and screw worm larva counts, and provided a significant increase (23 kg) of live weight gain in relation to untreated animals.

  17. Feasibility of a controlled trial aiming to prevent excessive pregnancy-related weight gain in primary health care

    Directory of Open Access Journals (Sweden)

    Weiderpass Elisabete

    2008-08-01

    Full Text Available Abstract Background Excessive gestational weight gain and postpartum weight retention may predispose women to long-term overweight and other health problems. Intervention studies aiming at preventing excessive pregnancy-related weight gain are needed. The feasibility of implementing such a study protocol in primary health care setting was evaluated in this pilot study. Methods A non-randomized controlled trial was conducted in three intervention and three control maternity and child health clinics in primary health care in Finland. Altogether, 132 pregnant and 92 postpartum women and 23 public health nurses (PHN participated in the study. The intervention consisted of individual counselling on physical activity and diet at five routine visits to a PHN and of an option for supervised group exercise until 37 weeks' gestation or ten months postpartum. The control clinics continued their usual care. The components of the feasibility evaluation were 1 recruitment and participation, 2 completion of data collection, 3 realization of the intervention and 4 the public health nurses' experiences. Results 1 The recruitment rate was slower than expected and the recruitment period had to be prolonged from the initially planned three months to six months. The average participation rate of eligible women at study enrolment was 77% and the drop-out rate 15%. 2 In total, 99% of the data on weight, physical activity and diet and 96% of the blood samples were obtained. 3 In the intervention clinics, 98% of the counselling sessions were realized, their contents and average durations were as intended, 87% of participants regularly completed the weekly records for physical activity and diet, and the average participation percentage in the group exercise sessions was 45%. 4 The PHNs regarded the extra training as a major advantage and the high additional workload as a disadvantage of the study. Conclusion The study protocol was mostly feasible to implement, which

  18. Mastitis therapy and control - Automatic on-line detection of abnormal milk.

    NARCIS (Netherlands)

    Hogeveen, H.

    2011-01-01

    Automated online detection of mastitis and abnormal milk is an important subject in the dairy industry, especially because of the introduction of automatic milking systems and the growing farm sizes with consequently less labor available per cow. Demands for performance, which is expressed as sensit

  19. AutoSync : Automatic duty-cycle control for synchronous low-power listening

    DEFF Research Database (Denmark)

    Hansen, Morten Tranberg; Kusy, Branislav; Jurdak, Raja;

    2012-01-01

    resources doing idle listening. This problem is particularly exacerbated in multi-radio networks where majority of data comes through the most reliable radio and the duty cycles of other radios could be reduced. We address this issue in AutoSync, a protocol that combines synchronous LPL with automatic...

  20. Saccadic eye movements in a high-speed bimanual stacking task: changes of attentional control during learning and automatization.

    Science.gov (United States)

    Foerster, Rebecca M; Carbone, Elena; Koesling, Hendrik; Schneider, Werner X

    2011-06-10

    Principles of saccadic eye movement control in the real world have been derived by the study of self-paced well-known tasks such as sandwich or tea making. Little is known whether these principles generalize to high-speed sensorimotor tasks and how they are affected by learning and automatization. In the present study, right-handers practiced the speed-stacking task in 14 consecutive daily training sessions, while their eye movements were recorded. Speed stacking is a high-speed sensorimotor task that requires grasping, moving, rotating, and placing of objects. The following main results emerged. Throughout practice, the eyes led the hands, displayed by a positive eye-hand time span. Moreover, visual information was gathered for the subsequent manual sub-action, displayed by a positive eye-hand unit span. With automatization, the eye-hand time span became shorter, yet it increased when corrected by the decreasing trial duration. In addition, fixations were mainly allocated to the goal positions of the right hand or objects in the right hand. The number of fixations decreased while the fixation rate remained constant. Importantly, all participants fixated on the same task-relevant locations in a similar scan path across training days, revealing a long-term memory-based mode of attention control after automatization of a high-speed sensorimotor task.

  1. Photoresponsive carbohydrate-based giant surfactants: automatic vertical alignment of nematic liquid crystal for the remote-controllable optical device.

    Science.gov (United States)

    Kim, Dae-Yoon; Lee, Sang-A; Kang, Dong-Gue; Park, Minwook; Choi, Yu-Jin; Jeong, Kwang-Un

    2015-03-25

    Photoresponsive carbohydrate-based giant surfactants (abbreviated as CELAnD-OH) were specifically designed and synthesized for the automatic vertical alignment (VA) layer of nematic (N) liquid crystal (LC), which can be applied for the fabrication of remote-controllable optical devices. Without the conventional polymer-based LC alignment process, a perfect VA layer was automatically constructed by directly adding the 0.1 wt % CELA1D-OH in the N-LC media. The programmed CELA1D-OH giant surfactants in the N-LC media gradually diffused onto the substrates of LC cell and self-assembled to the expanded monolayer structure, which can provide enough empty spaces for N-LC molecules to crawl into the empty zones for the construction of VA layer. On the other hand, the CELA3D-OH giant surfactants forming the condensed monolayer structure on the substrates exhibited a planar alignment (PA) rather than a VA. Upon tuning the wavelength of light, the N-LC alignments were reversibly switched between VA and PA in the remote-controllable LC optical devices. Based on the experimental results, it was realized that understanding the interactions between N-LC molecules and amphiphilic giant surfactants is critical to design the suitable materials for the automatic LC alignment.

  2. Vision system for driving control using camera mounted on an automatic vehicle. Jiritsu sokosha no camera ni yoru shikaku system

    Energy Technology Data Exchange (ETDEWEB)

    Nishimori, K.; Ishihara, K.; Tokutaka, H.; Kishida, S.; Fujimura, K. (Tottori University, Tottori (Japan). Faculty of Engineering); Okada, M. (Mazda Corp., Hiroshima (Japan)); Hirakawa, S. (Fujitsu Corp., Tokyo (Japan))

    1993-11-30

    The present report explains a vision system, in which a CCD camera, used for the model vehicle automatically traveling by fuzzy control, is used as a vision sensor. The vision system is composed of input image processing module, situation recognition/analysis module to three-dimensionally recover the road, route-selecting navigation module to avoid the obstacle and vehicle control module. The CCD camera is used as a vision sensor to make the model vehicle automatically travel by fuzzy control with the above modules. In the present research, the traveling is controlled by treating the position and configuration of objective in image as a fuzzy inferential variable. Based on the above method, the traveling simulation gave the following knowledge: even with the image information only from the vision system, the application of fuzzy control facilitates the traveling. If the objective is clearly known, the control is judged able to be made even from vague image which does not necessitate the exact locative information. 4 refs., 11 figs.

  3. Distributed cerebellar plasticity implements adaptable gain control in a manipulation task: a closed-loop robotic simulation

    Directory of Open Access Journals (Sweden)

    Jesus A Garrido Alcazar

    2013-10-01

    Full Text Available Adaptable gain regulation is at the core of the forward controller operation performed by the cerebro-cerebellar loops and it allows the intensity of motor acts to be finely tuned in a predictive manner. In order to learn and store information about body-object dynamics and to generate an internal model of movement, the cerebellum is thought to employ long-term synaptic plasticity. LTD at the PF-PC synapse has classically been assumed to subserve this function (Marr, 1969. However, this plasticity alone cannot account for the broad dynamic ranges and time scales of cerebellar adaptation. We therefore tested the role of plasticity distributed over multiple synaptic sites (Gao et al., 2012; Hansel et al., 2001 by generating an analog cerebellar model embedded into a control loop connected to a robotic simulator. The robot used a three-joint arm and performed repetitive fast manipulations with different masses along an 8-shape trajectory. In accordance with biological evidence, the cerebellum model was endowed with both LTD and LTP at the PF-PC, MF-DCN and PC-DCN synapses. This resulted in a network scheme whose effectiveness was extended considerably compared to one including just PF-PC synaptic plasticity. Indeed, the system including distributed plasticity reliably self-adapted to manipulate different masses and to learn the arm-object dynamics over a time course that included fast learning and consolidation, along the lines of what has been observed in behavioral tests. In particular, PF-PC plasticity operated as a time correlator between the actual input state and the system error, while MF-DCN and PC-DCN plasticity played a key role in generating the gain controller. This model suggests that distributed synaptic plasticity allows generation of the complex learning properties of the cerebellum. The incorporation of further plasticity mechanisms and of spiking signal processing will allow this concept to be extended in a more realistic

  4. Weight gain is associated with improved glycaemic control but with adverse changes in plasma lipids and blood pressure isn Type 1 diabetes.

    LENUS (Irish Health Repository)

    Ferriss, J B

    2012-02-03

    AIMS: To assess the effects of weight gain on metabolic control, plasma lipids and blood pressure in patients with Type 1 diabetes. METHODS: Patients in the EURODIAB Prospective Complications Study (n = 3250) were examined at baseline and 1800 (55%) were re-examined a mean of 7.3 years later. Patients had Type 1 diabetes, defined as a diagnosis made before age 36 years and with a need for continuous insulin therapy within a year of diagnosis. Patients were aged 15-60 years at baseline and were stratified for age, sex and duration of diabetes. RESULTS: The change in HbA(1c) from baseline to follow-up examination was significantly more favourable in those who gained 5 kg or more during follow-up (\\'marked weight gain\\') than in patients who gained less or no weight or lost weight (\\'less or no weight gain\\'). In those with marked weight gain, there was a significantly greater rise in plasma triglycerides and total cholesterol and significantly less favourable changes in low-density lipoprotein and high-density lipoprotein cholesterol compared with those with less or no weight gain, with or without adjustment for HbA(1c). Systolic and diastolic blood pressure also rose significantly more in the group with marked weight gain. CONCLUSION: Weight gain in patients with Type 1 diabetes has adverse effects on plasma lipids and blood pressure, despite a small improvement in glycaemic control.

  5. Development of Digital Hysteresis Current Control with PLL Loop Gain Compensation Strategy for PWM Inverters with Constant Switching Frequency

    Directory of Open Access Journals (Sweden)

    N. Belhaouchet

    2008-03-01

    Full Text Available Hysteresis current control is one of the simplest techniques used to control the magnitude and phase angle of motor current for motor drives systems. However, this technique presents several disadvantages such as operation at variable switching frequency which can reveal problems of filtering, interference between the phases in the case of the three-phase systems with insulated neutral connection or delta connection, and irregularity of the modulation pulses which especially causes an acoustic noise on the level of the machine for the high power drive. In this paper, a new technique is proposed for a variable-hysteresis-band controller based on dead beat control applied to three phase voltage source PWM inverters feeding AC motors. Its main aim is firstly ensure a constant switching frequency and secondly the synchronization of modulation pulses using the phase-locked-loop with loop gain compensation in order to ensure a better stability. The behavior of the proposed technique is verified by simulation.

  6. 玉米胚芽油厂自动化控制技术的应用%Application of automatic control in corn germ oil plant

    Institute of Scientific and Technical Information of China (English)

    崔宝贵

    2012-01-01

    The scope,characteristics,basic status and the development in recent years of automatic control in corn germ oil plant was introduced.The functions of automatic control in deodorization,alkali refining and decoloration were analyzed.The difference between process with or without automatic control was compared.The importance of cooperate between technicians of both in production and automatic control during design and management was emphasized.%介绍了玉米胚芽油厂自动化控制的范围、特点、基本状况和近年的发展,分析了自动化在脱臭、碱炼、脱色的作用,对比了自动化前后的差别。强调了油脂专业与自动化控制人员在设计、管理中的作用与配合。

  7. PLC自动控制系统可靠性提升研究%Discussion on the Reliability Improvement of Plc Automatic Control System

    Institute of Scientific and Technical Information of China (English)

    赵聪

    2015-01-01

    随着我国工业快速发展,各种自动化系统也在不断得以运用与完善,PLC自动控制系统结合了可编程控制器和继电器控制器的优点,形成一套完整的、自动化的控制系统。PLC自动控制系统由于在数据传输以及硬件设备使用的过程中易出错,从而降低PLC自动控制系统的可靠性,因此本文就如何提升PLC自动控制系统的可靠性展开论述。%Along with the fast development of industry in our country,all kinds of automatic systems also have continuous improvement and application,PLC automatic control system combined the advantages of programming controller and a relay controller,formed a complete set of automatic control system. Because PLC automatic control system in the process of data transmission and hardware using process tends to be wrong,thus reducing the reliability of PLC automatic control system. This paper discussed how to enhance the reliability of PLC automatic control system..

  8. Telemetric control of heart adaptation during automatic and free-fall parachute jumps.

    Science.gov (United States)

    Deroanne, R; Cession-Fossion, A; Juchmes, J; Servais, J C; Petit, J M

    1975-02-01

    Telmetered heart rate recordings have been ovtaine from 17 parachutists (6 during automatic jumps) 9 Catecholamine (adrenaline and noradrenaline) concentrations have been measured in urine and plasma of six of these subjects. No difference appears between heart rates recorded in the two jumps at egress and at parachute deployment. On the other hand, higher heart rate values are recorded during automatic jumps during descent and at ground impace. The urine catecholamine analysis after jump shows a statistically significant increase in adrenaline and noradrenaline concentration. It is suggested that simulation of the orthosympathetic system is due to two facts; muscular work performed during jumping and the emotional stress which it involves. The importance of these two causes varies with the jump circumstances.

  9. A gene-based information gain method for detecting gene-gene interactions in case-control studies.

    Science.gov (United States)

    Li, Jin; Huang, Dongli; Guo, Maozu; Liu, Xiaoyan; Wang, Chunyu; Teng, Zhixia; Zhang, Ruijie; Jiang, Yongshuai; Lv, Hongchao; Wang, Limei

    2015-11-01

    Currently, most methods for detecting gene-gene interactions (GGIs) in genome-wide association studies are divided into SNP-based methods and gene-based methods. Generally, the gene-based methods can be more powerful than SNP-based methods. Some gene-based entropy methods can only capture the linear relationship between genes. We therefore proposed a nonparametric gene-based information gain method (GBIGM) that can capture both linear relationship and nonlinear correlation between genes. Through simulation with different odds ratio, sample size and prevalence rate, GBIGM was shown to be valid and more powerful than classic KCCU method and SNP-based entropy method. In the analysis of data from 17 genes on rheumatoid arthritis, GBIGM was more effective than the other two methods as it obtains fewer significant results, which was important for biological verification. Therefore, GBIGM is a suitable and powerful tool for detecting GGIs in case-control studies.

  10. Gimbals Drive and Control Electronics Design, Development and Testing of the LRO High Gain Antenna and Solar Array Systems

    Science.gov (United States)

    Chernyakov, Boris; Thakore, Kamal

    2010-01-01

    Launched June 18, 2009 on an Atlas V rocket, NASA's Lunar Reconnaissance Orbiter (LRO) is the first step in NASA's Vision for Space Exploration program and for a human return to the Moon. The spacecraft (SC) carries a wide variety of scientific instruments and provides an extraordinary opportunity to study the lunar landscape at resolutions and over time scales never achieved before. The spacecraft systems are designed to enable achievement of LRO's mission requirements. To that end, LRO's mechanical system employed two two-axis gimbal assemblies used to drive the deployment and articulation of the Solar Array System (SAS) and the High Gain Antenna System (HGAS). This paper describes the design, development, integration, and testing of Gimbal Control Electronics (GCE) and Actuators for both the HGAS and SAS systems, as well as flight testing during the on-orbit commissioning phase and lessons learned.

  11. Gaining control over responses to implicit attitude tests: Implementation intentions engender fast responses on attitude-incongruent trials.

    Science.gov (United States)

    Webb, Thomas L; Sheeran, Paschal; Pepper, John

    2012-03-01

    The present research investigated whether forming implementation intentions could promote fast responses to attitude-incongruent associations (e.g., woman-manager) and thereby modify scores on popular implicit measures of attitude. Expt 1 used the Implicit Association Test (IAT) to measure associations between gender and science versus liberal arts. Planning to associate women with science engendered fast responses to this category-attribute pairing and rendered summary scores more neutral compared to standard IAT instructions. Expt 2 demonstrated that forming egalitarian goal intentions is not sufficient to produce these effects. Expt 3 extended these findings to a different measure of implicit attitude (the Go/No-Go Association Task) and a different stereotypical association (Muslims-terrorism). In Expt 4, managers who planned to associate women with superordinate positions showed more neutral IAT scores relative to non-planners and effects were maintained 3 weeks later. In sum, implementation intentions enable people to gain control over implicit attitude responses.

  12. Research methodology simplification for teaching purposes illustrated by clutch automatic control device testing

    Science.gov (United States)

    Wojs, J.

    2016-09-01

    The paper proves that simplified, shorter examination of an object, feasible in laboratory classes, can produce results similar to those reached in scientific investigation of the device using extensive equipment. A thorough investigation of an object, an automatic clutch device in this case, enabled identifying the magnitudes that most significantly affect its operation. The knowledge of these most sensitive magnitudes allows focusing in the teaching process on simplified measurement of only selected magnitudes and verifying the given object in the positive or negative.

  13. Asthma Triggers: Gain Control

    Science.gov (United States)

    Jump to main content US EPA United States Environmental Protection Agency Search Search Asthma Share Facebook Twitter Google+ ... remove an animal from the home, it is important to thoroughly clean the floors, walls, carpets and ...

  14. 飞翼布局无人机反步L2增益纵向着陆鲁棒控制%Backstepping L2 gain robust control of longitudinal landing of flying-wing UAV

    Institute of Scientific and Technical Information of China (English)

    谭健; 周洲; 祝小平; 许晓平

    2016-01-01

    For the longitudinal landing control problem of flying⁃wing UAV with unknown external disturbances, a backstepping L2 gain robust control scheme based on super twisting sliding mode disturbance observer and tracking differentiator is proposed. The tracking differentiator is introduced to calculate the derivative of virtual control law which is very difficult to evaluate with the traditional backstepping control. Super twisting sliding mode disturbance observer and L2 gain robust item are designed to increase the robustness of the control system. Simulation results show:the altitude and airspeed of UAV are tracked on control command, vertical ground speed is within the allowable range. Compared with traditional PID control scheme, the proposed control scheme has better automatical landing control performance.%针对存在干扰的飞翼布局无人机纵向着陆控制问题,提出一种基于super twisting滑模干扰观测器与跟踪微分器的反步L2增益鲁棒控制方案。为解决反步控制虚拟控制量求导复杂的问题,设计了跟踪微分器对虚拟控制量进行求导,同时综合采用super twisting滑模干扰观测器和L2增益鲁棒项增强了控制系统的鲁棒性。仿真结果表明,无人机高度、空速都跟踪上控制指令,垂直接地速度在允许的范围内,与传统的PID着陆控制方案相比具有更好的着陆控制性能。

  15. Determination of all feasible robust PID controllers for open-loop unstable plus time delay processes with gain margin and phase margin specifications.

    Science.gov (United States)

    Wang, Yuan-Jay

    2014-03-01

    This paper proposes a novel alternative method to graphically compute all feasible gain and phase margin specifications-oriented robust PID controllers for open-loop unstable plus time delay (OLUPTD) processes. This method is applicable to general OLUPTD processes without constraint on system order. To retain robustness for OLUPTD processes subject to positive or negative gain variations, the downward gain margin (GM(down)), upward gain margin (GM(up)), and phase margin (PM) are considered. A virtual gain-phase margin tester compensator is incorporated to guarantee the concerned system satisfies certain robust safety margins. In addition, the stability equation method and the parameter plane method are exploited to portray the stability boundary and the constant gain margin (GM) boundary as well as the constant PM boundary. The overlapping region of these boundaries is graphically determined and denotes the GM and PM specifications-oriented region (GPMSOR). Alternatively, the GPMSOR characterizes all feasible robust PID controllers which achieve the pre-specified safety margins. In particular, to achieve optimal gain tuning, the controller gains are searched within the GPMSOR to minimize the integral of the absolute error (IAE) or the integral of the squared error (ISE) performance criterion. Thus, an optimal PID controller gain set is successfully found within the GPMSOR and guarantees the OLUPTD processes with a pre-specified GM and PM as well as a minimum IAE or ISE. Consequently, both robustness and performance can be simultaneously assured. Further, the design procedures are summarized as an algorithm to help rapidly locate the GPMSOR and search an optimal PID gain set. Finally, three highly cited examples are provided to illustrate the design process and to demonstrate the effectiveness of the proposed method.

  16. Differences in semantic category priming in the left and right cerebral hemispheres under automatic and controlled processing conditions.

    Science.gov (United States)

    Collins, M

    1999-08-01

    The contribution of each cerebral hemisphere to the generation of semantic category meanings at automatic and strategic levels of processing was investigated in a priming experiment where prime and target words were independently projected to the left or right visual fields (LVF or RVF). Non-associated category exemplars were employed as related pairs in a lexical decision task and presented in two experimental conditions. The first condition was designed to elicit automatic processing, so related pairs comprised 20% of the positive set, stimulus pairs were temporally separated by a stimulus onset asynchrony (SOA) of 250 ms, and there was no allusion to the presence of related pairs in the instructions to subjects. The second condition, designed to invoke controlled processing, incorporated a relatedness proportion of 50%, stimulus pairs separated by an SOA of 750 ms, and instructions which informed subjects of the presence and use of category exemplar pairs in the stimulus set. In the first condition, a prime directed to either visual field facilitated responses to categorically related targets subsequently projected to the RVF, while in the second condition a prime directed to either visual field facilitated responses to related targets projected to the LVF. The facilitation effects obtained in both conditions appeared to reflect automatic processes, while strategic processes were invoked in the left, but not the right hemisphere in the second condition. The results suggest that both hemispheres have automatic access to semantic category meanings, although the timecourse of activation of semantic category meanings is slower in the right hemisphere than in the left.

  17. Automatic HDL firmware generation for FPGA-based reconfigurable measurement and control systems with mezzanines in FMC standard

    Science.gov (United States)

    Wojenski, Andrzej; Kasprowicz, Grzegorz; Pozniak, Krzysztof T.; Romaniuk, Ryszard

    2013-10-01

    The paper describes a concept of automatic firmware generation for reconfigurable measurement systems, which uses FPGA devices and measurement cards in FMC standard. Following sections are described in details: automatic HDL code generation for FPGA devices, automatic communication interfaces implementation, HDL drivers for measurement cards, automatic serial connection between multiple measurement backplane boards, automatic build of memory map (address space), automatic generated firmware management. Presented solutions are required in many advanced measurement systems, like Beam Position Monitors or GEM detectors. This work is a part of a wider project for automatic firmware generation and management of reconfigurable systems. Solutions presented in this paper are based on previous publication in SPIE.

  18. Fuzzy control on automatic frequency tracking of ultrasonic vibration system with high power and high quality factor Q

    Institute of Scientific and Technical Information of China (English)

    ZHU Wu; ZHANG Jia-min; LIU Hong-li; MENG Feng-feng; ZHANG Zhi-ming

    2009-01-01

    In order to realize automatic tracking drift of resonance frequency of ultrasonic vibration system with high power and high quality factor Q, adaptive fuzzy control was studied with a self-fabricated ultrasonic plastic welding machine. At first, relations between amplitude of vibration and frequency as well as main loop current and amplitude of vibration were analyzed. From this analysis, we deduced that frequency tracking process of the vibration system can be concluded as an optimizing problem of one dimensional fluctuant extremum of main loop current in vibration system. Then a method of self-optimizing fuzzy control, used for the realization of automatic frequency tracking in vibration system, is presented on the basis of self-optimizing adaptive control approach and fuzzy control approach. The result of experiments shows that the fuzzy self-optimizing method can solve the problem of tracking frequency drift very well. Response time of tracking in the system is less than 50 ms, which basically meets the requirements of frequency tracking in ultrasonic plastic welding machine.

  19. Decoupling of automatic control systems in a continuous-wave electron paramagnetic resonance spectrometer for biomedical applications.

    Science.gov (United States)

    Hirata, Hiroshi; Watanabe, Hiroyuki; Kumada, Masaharu; Itoh, Kouichi; Fujii, Hirotada

    2004-08-01

    This article describes a systematic approach to decoupling automatic tuning control (ATC) and automatic matching control (AMC) systems in continuous-wave (CW) electron paramagnetic resonance (EPR) spectroscopy for animal experiments. This technique enables us to improve the stability of CW-EPR spectroscopy even if the animal is moving during the data acquisition of EPR spectra. The control systems are formulated to allow the behavior of interference between them to be investigated, since they are generally coupled due to the characteristics of the microwave resonator. The stability of the entire control system in a 1.1 GHz CW-EPR spectrometer is evaluated with the generalized Nyquist stability criterion. We compare the EPR spectra of a triarylmethyl (TAM) radical that is dosed in anesthetized mice in terms of the signal-to-noise ratio (SNR) to test the precompensator for decoupling the ATC and AMC systems. The experimental findings suggest that the present technique is useful for improving the SNR of EPR spectra in animal experiments. The SNR of the measured EPR spectra was improved by about 50% with the precompensator.

  20. Wind power integration into the automatic generation control of power systems with large-scale wind power

    DEFF Research Database (Denmark)

    Basit, Abdul; Hansen, Anca Daniela; Altin, Müfit

    2014-01-01

    Transmission system operators have an increased interest in the active participation of wind power plants (WPP) in the power balance control of power systems with large wind power penetration. The emphasis in this study is on the integration of WPPs into the automatic generation control (AGC......) of the power system. The present paper proposes a coordinated control strategy for the AGC between combined heat and power plants (CHPs) and WPPs to enhance the security and the reliability of a power system operation in the case of a large wind power penetration. The proposed strategy, described...... and exemplified for the future Danish power system, takes the hour-ahead regulating power plan for generation and power exchange with neighbouring power systems into account. The performance of the proposed strategy for coordinated secondary control is assessed and discussed by means of simulations for different...