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Sample records for activity control technique

  1. Active load control techniques for wind turbines.

    Energy Technology Data Exchange (ETDEWEB)

    van Dam, C.P. (University of California, Davis, CA); Berg, Dale E.; Johnson, Scott J. (University of California, Davis, CA)

    2008-07-01

    This report provides an overview on the current state of wind turbine control and introduces a number of active techniques that could be potentially used for control of wind turbine blades. The focus is on research regarding active flow control (AFC) as it applies to wind turbine performance and loads. The techniques and concepts described here are often described as 'smart structures' or 'smart rotor control'. This field is rapidly growing and there are numerous concepts currently being investigated around the world; some concepts already are focused on the wind energy industry and others are intended for use in other fields, but have the potential for wind turbine control. An AFC system can be broken into three categories: controls and sensors, actuators and devices, and the flow phenomena. This report focuses on the research involved with the actuators and devices and the generated flow phenomena caused by each device.

  2. Magnetic Levitation Technique for Active Vibration Control

    OpenAIRE

    Hoque, Emdadul; Mizuno, Takeshi

    2010-01-01

    A zero-power controlled magnetic levitation system has been presented in this chapter. The unique characteristic of the zero-power control system is that it can generate negative stiffness with zero control current in the steady-state which is realized in this chapter. The detail characteristics of the levitation system are investigated. Moreover, two major contributions, the stiffness adjustment and nonlinear compensation of the suspension system have been introduced elaborately. Often, ther...

  3. Active structural control with stable fuzzy PID techniques

    CERN Document Server

    Yu, Wen

    2016-01-01

    This book presents a detailed discussion of intelligent techniques to measure the displacement of buildings when they are subjected to vibration. It shows how these techniques are used to control active devices that can reduce vibration 60–80% more effectively than widely used passive anti-seismic systems. After introducing various structural control devices and building-modeling and active structural control methods, the authors propose offset cancellation and high-pass filtering techniques to solve some common problems of building-displacement measurement using accelerometers. The most popular control algorithms in industrial settings, PD/PID controllers, are then analyzed and then combined with fuzzy compensation. The stability of this combination is proven with standard weight-training algorithms. These conditions provide explicit methods for selecting PD/PID controllers. Finally, fuzzy-logic and sliding-mode control are applied to the control of wind-induced vibration. The methods described are support...

  4. Active vibration control techniques for flexible space structures

    Science.gov (United States)

    Parlos, Alexander G.; Jayasuriya, Suhada

    1990-01-01

    Two proposed control system design techniques for active vibration control in flexible space structures are detailed. Control issues relevant only to flexible-body dynamics are addressed, whereas no attempt was made to integrate the flexible and rigid-body spacecraft dynamics. Both of the proposed approaches revealed encouraging results; however, further investigation of the interaction of the flexible and rigid-body dynamics is warranted.

  5. Application of Active Flow Control Technique for Gust Load Alleviation

    Institute of Scientific and Technical Information of China (English)

    XU Xiaoping; ZHU Xiaoping; ZHOU Zhou; FAN Ruijun

    2011-01-01

    A new gust load alleviation technique is presented in this paper based on active flow control.Numerical studies are conducted to investigate the beneficial effects on the aerodynamic characteristics of the quasi “Global Hawk” airfoil using arrays of jets during the gust process.Based on unsteady Navier-Stokes equations,the grid-velocity method is introduced to simulate the gust influence,and dynamic response in vertical gust flow perturbation is investigated for the airfoil as well.An unsteady surface transpiration boundary condition is enforced over a user specified portion of the airfoil's surface to emulate the time dependent velocity boundary conditions.Firstly,after applying this method to simulate typical NACA0006 airfoil gust response to a step change in the angle of attack,it shows that the indicial responses of the airfoil make good agreement with the exact theoretical values and the calculated values in references.Furthermore,gust response characteristic for the quasi “Global Hawk” airfoil is analyzed.Five kinds of flow control techniques are introduced as steady blowing,steady suction,unsteady blowing,unsteady suction and synthetic jets.The physical analysis of the influence on the effects of gust load alleviation is proposed to provide some guidelines for practice.Numerical results have indicated that active flow control technique,as a new technology of gust load alleviation,can affect and suppress the fluid disturbances caused by gust so as to achieve the purpose of gust load alleviation.

  6. Active control technique of fractional-order chaotic complex systems

    Science.gov (United States)

    Mahmoud, Gamal M.; Ahmed, Mansour E.; Abed-Elhameed, Tarek M.

    2016-06-01

    Several kinds of synchronization of fractional-order chaotic complex systems are challenging research topics of current interest since they appear in many applications in applied sciences. Our main goal in this paper is to introduce the definition of modified projective combination-combination synchronization (MPCCS) of some fractional-order chaotic complex systems. We show that our systems are chaotic by calculating their Lyapunov exponents. The fractional Lyapunov dimension of the chaotic solutions of these systems is computed. A scheme is introduced to calculate MPCCS of four different (or identical) chaotic complex systems using the active control technique. Special cases of this type, which are projective and anti C-C synchronization, are discussed. Some figures are plotted to show that MPCCS is achieved and its errors approach zero.

  7. The virtual microphone technique in active sound field control systems

    Science.gov (United States)

    Lampropoulos, Iraklis E.; Shimizu, Yasushi

    2003-04-01

    Active Sound Field Control (AFC) has been proven very useful in reverberation enhancement applications in large rooms. However, feedback control is required in order to eliminate peaks in the frequency response of the system. The present research closely follows the studies of Shimizu in AFC, in which smoothing of the rooms transfer function is achieved by averaging the impulse responses of multiple microphones. ``The virtual or rotating microphone technique'' reduces the number of microphones in the aforementioned AFC technology, while still achieving the same acoustical effects in the room. After the impulse responses at previously specified pairs of microphone positions are measured, the ratio of transfer functions for every pair is calculated, thus yielding a constant K. Next, microphones are removed and their impulse responses are reproduced by processing the incoming signal of each pair through a convolver, where the computed K constants have been previously stored. Band limiting, windowing and time variance effects are critical factors, in order to reduce incoherence effects and yield reliable approximations of inverse filters and consequently calculations of K. The project is implemented in a church lacking low frequency reverberation for music and makes use of 2 physical and 2 virtual microphones.

  8. Modern control techniques in active flutter suppression using a control moment gyro

    Science.gov (United States)

    Buchek, P. M.

    1974-01-01

    Development of organized synthesis techniques, using concepts of modern control theory was studied for the design of active flutter suppression systems for two and three-dimensional lifting surfaces, utilizing a control moment gyro (CMG) to generate the required control torques. Incompressible flow theory is assumed, with the unsteady aerodynamic forces and moments for arbitrary airfoil motion obtained by using the convolution integral based on Wagner's indicial lift function. Linear optimal control theory is applied to find particular optimal sets of gain values which minimize a quadratic performance function. The closed loop system's response to impulsive gust disturbances and the resulting control power requirements are investigated, and the system eigenvalues necessary to minimize the maximum value of control power are determined.

  9. Control and switching synchronization of fractional order chaotic systems using active control technique

    KAUST Repository

    Radwan, A.G.

    2013-03-13

    This paper discusses the continuous effect of the fractional order parameter of the Lü system where the system response starts stable, passing by chaotic behavior then reaching periodic response as the fractional-order increases. In addition, this paper presents the concept of synchronization of different fractional order chaotic systems using active control technique. Four different synchronization cases are introduced based on the switching parameters. Also, the static and dynamic synchronizations can be obtained when the switching parameters are functions of time. The nonstandard finite difference method is used for the numerical solution of the fractional order master and slave systems. Many numeric simulations are presented to validate the concept for different fractional order parameters.

  10. Control and switching synchronization of fractional order chaotic systems using active control technique

    Directory of Open Access Journals (Sweden)

    A.G. Radwan

    2014-01-01

    Full Text Available This paper discusses the continuous effect of the fractional order parameter of the Lü system where the system response starts stable, passing by chaotic behavior then reaching periodic response as the fractional-order increases. In addition, this paper presents the concept of synchronization of different fractional order chaotic systems using active control technique. Four different synchronization cases are introduced based on the switching parameters. Also, the static and dynamic synchronizations can be obtained when the switching parameters are functions of time. The nonstandard finite difference method is used for the numerical solution of the fractional order master and slave systems. Many numeric simulations are presented to validate the concept for different fractional order parameters.

  11. Development of active control technique for engine noise. Engine soon no active seigyo gijutsu no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, H.; Nakao, N.; Butsuen, T. (Mazda Motor Corp., Hiroshima (Japan))

    1994-03-31

    As a measure to reduce engine noise in a car, the active noise control (ANC) technique to eliminate noise by another noise of antiphase has been studied. The conventional filtered-x LMS control algorithm has been generally applied to the ANC, but a large quantity of arithmetic operation used for filtering is practically problematic. This paper proposes the new algorithm of which control effects and practicability have been improved by utilizing periodicity of engine noise and by introducing the idea of error scanning. This algorithm requires only 30-50% of the arithmetic operation of the above LMS method. Concerning the actual system structure, arrangement and the number of microphones have been examined based on the detailed measurement results of the spatial distribution of noise in a car. As a result, the suitable arrangement of only three microphones to reduce noise in the whole interior space of a car is found. Through the experiments, maximum noise reduction of 8dB (A scale) has been achieved at each seat position. 7 refs., 9 figs., 1 tab.

  12. A new hysteresis band current control technique for a shunt active filter

    OpenAIRE

    KALE, MURAT; ÖZDEMİR, ENGİN

    2015-01-01

    This paper proposes a hysteresis band (HB) current control technique to reduce the power losses in a shunt active filter. During a switching period in the zero-crossing region, the inverter output current flows through a transistor. By changing the direction, it flows through the free-wheeling diode of the same switch in an inverter leg, or vice versa. The shunt active filter current typically has 6 zero-crossing regions during a fundamental frequency cycle. This paper presents a HB current c...

  13. Control System Design of Shunt Active Power Filter Based on Active Disturbance Rejection and Repetitive Control Techniques

    Directory of Open Access Journals (Sweden)

    Le Ge

    2014-01-01

    Full Text Available To rely on joint active disturbance rejection control (ADRC and repetitive control (RC, in this paper, a compound control law for active power filter (APF current control system is proposed. According to the theory of ADRC, the uncertainties in the model and from the circumstance outside are considered as the unknown disturbance to the system. The extended state observer can evaluate the unknown disturbance. Next, RC is introduced into current loop to improve the steady characteristics. The ADRC is used to get a good dynamic performance, and RC is used to get a good static performance. A good simulation result is got through choosing and changing the parameters, and the feasibility, adaptability, and robustness of the control are testified by this result.

  14. Contamination Control Techniques

    Energy Technology Data Exchange (ETDEWEB)

    EBY, J.L.

    2000-05-16

    Welcome to a workshop on contamination Control techniques. This work shop is designed for about two hours. Attendee participation is encouraged during the workshop. We will address different topics within contamination control techniques; present processes, products and equipment used here at Hanford and then open the floor to you, the attendees for your input on the topics.

  15. Contamination Control Techniques

    International Nuclear Information System (INIS)

    Welcome to a workshop on contamination Control techniques. This work shop is designed for about two hours. Attendee participation is encouraged during the workshop. We will address different topics within contamination control techniques; present processes, products and equipment used here at Hanford and then open the floor to you, the attendees for your input on the topics

  16. Experimental studies of active and passive flow control techniques applied in a twin air-intake.

    Science.gov (United States)

    Paul, Akshoy Ranjan; Joshi, Shrey; Jindal, Aman; Maurya, Shivam P; Jain, Anuj

    2013-01-01

    The flow control in twin air-intakes is necessary to improve the performance characteristics, since the flow traveling through curved and diffused paths becomes complex, especially after merging. The paper presents a comparison between two well-known techniques of flow control: active and passive. It presents an effective design of a vortex generator jet (VGJ) and a vane-type passive vortex generator (VG) and uses them in twin air-intake duct in different combinations to establish their effectiveness in improving the performance characteristics. The VGJ is designed to insert flow from side wall at pitch angle of 90 degrees and 45 degrees. Corotating (parallel) and counterrotating (V-shape) are the configuration of vane type VG. It is observed that VGJ has the potential to change the flow pattern drastically as compared to vane-type VG. While the VGJ is directed perpendicular to the side walls of the air-intake at a pitch angle of 90 degree, static pressure recovery is increased by 7.8% and total pressure loss is reduced by 40.7%, which is the best among all other cases tested for VGJ. For bigger-sized VG attached to the side walls of the air-intake, static pressure recovery is increased by 5.3%, but total pressure loss is reduced by only 4.5% as compared to all other cases of VG.

  17. Active Flow Control with Adaptive Design Techniques for Improved Aircraft Safety Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The increased aircraft safety potential of active flow control using synthetic jets - specifically, using synthetic jets on the leading edge of the wing to delay...

  18. Linear and Non-Linear Control Techniques Applied to Actively Lubricated Journal Bearings

    DEFF Research Database (Denmark)

    Nicoletti, Rodrigo; Santos, Ilmar

    2003-01-01

    to a tilting-pad journal bearing, are analysed and discussed. Important conclusions about the application of integral controllers, responsible for changing the rotor-bearing equilibrium position and consequently the "passive" oil film damping coefficients, are achieved. Numerical results show an effective......The main objectives of actively lubricated bearings are the simultaneous reduction of wear and vibration between rotating and stationary machinery parts. For reducing wear and dissipating vibration energy until certain limits, one can count with the conventional hydrodynamic lubrication....... For further reduction of shaft vibrations one can count with the active lubrication action, which is based on injecting pressurised oil into the bearing gap through orifices machined in the bearing sliding surface. The design and efficiency of some linear (PD, PI and PID) and non-linear controllers, applied...

  19. Linear and non-linear control techniques applied to actively lubricated journal bearings

    Science.gov (United States)

    Nicoletti, R.; Santos, I. F.

    2003-03-01

    The main objectives of actively lubricated bearings are the simultaneous reduction of wear and vibration between rotating and stationary machinery parts. For reducing wear and dissipating vibration energy until certain limits, one can use the conventional hydrodynamic lubrication. For further reduction of shaft vibrations one can use the active lubrication action, which is based on injecting pressurized oil into the bearing gap through orifices machined in the bearing sliding surface. The design and efficiency of some linear (PD, PI and PID) and a non-linear controller, applied to a tilting-pad journal bearing, are analysed and discussed. Important conclusions about the application of integral controllers, responsible for changing the rotor-bearing equilibrium position and consequently the "passive" oil film damping coefficients, are achieved. Numerical results show an effective vibration reduction of unbalance response of a rigid rotor, where the PD and the non-linear P controllers show better performance for the frequency range of study (0-80 Hz). The feasibility of eliminating rotor-bearing instabilities (phenomena of whirl) by using active lubrication is also investigated, illustrating clearly one of its most promising applications.

  20. Active Interrogation using Photofission Technique for Nuclear Materials Control and Accountability

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Haori [Oregon State Univ., Corvallis, OR (United States)

    2016-03-31

    Innovative systems with increased sensitivity and resolution are in great demand to detect diversion and to prevent misuse in support of nuclear materials management for the U.S. fuel cycle. Nuclear fission is the most important multiplicative process involved in non-destructive active interrogation. This process produces the most easily recognizable signature for nuclear materials. In addition to thermal or high-energy neutrons, high-energy gamma rays can also excite a nucleus and cause fission through a process known as photofission. Electron linear accelerators (linac) are widely used as the interrogating photon sources for inspection methods involving photofission technique. After photofission reactions, prompt signals are much stronger than the delayed signals, but it is difficult to quantify them in practical measurements. Delayed signals are easily distinguishable from the interrogating radiation. linac-based, advanced inspection techniques utilizing the delayed signals after photofission have been extensively studied for homeland security applications. Previous research also showed that a unique delayed gamma ray energy spectrum exists for each fissionable isotope.

  1. Active Interrogation using Photofission Technique for Nuclear Materials Control and Accountability

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Haori [Oregon State Univ., Corvallis, OR (United States)

    2016-03-31

    Innovative systems with increased sensitivity and resolution are in great demand to detect diversion and to prevent misuse in support of nuclear materials management for the U.S. fuel cycle. Nuclear fission is the most important multiplicative process involved in non-destructive active interrogation. This process produces the most easily recognizable signature for nuclear materials. In addition to thermal or high-energy neutrons, high-energy gamma rays can also excite a nucleus and cause fission through a process known as photofission. Electron linear accelerators (linacs) are widely used as the interrogating photon sources for inspection methods involving photofission technique. After photofission reactions, prompt signals are much stronger than the delayed signals, but it is difficult to quantify them in practical measurements. Delayed signals are easily distinguishable from the interrogating radiation. linac-based, advanced inspection techniques utilizing the delayed signals after photofission have been extensively studied for homeland security applications. Previous research also showed that a unique delayed gamma ray energy spectrum exists for each fissionable isotope.

  2. Console Log Keeping Made Easier - Tools and Techniques for Improving Quality of Flight Controller Activity Logs

    Science.gov (United States)

    Scott, David W.; Underwood, Debrah (Technical Monitor)

    2002-01-01

    At the Marshall Space Flight Center's (MSFC) Payload Operations Integration Center (POIC) for International Space Station (ISS), each flight controller maintains detailed logs of activities and communications at their console position. These logs are critical for accurately controlling flight in real-time as well as providing a historical record and troubleshooting tool. This paper describes logging methods and electronic formats used at the POIC and provides food for thought on their strengths and limitations, plus proposes some innovative extensions. It also describes an inexpensive PC-based scheme for capturing and/or transcribing audio clips from communications consoles. Flight control activity (e.g. interpreting computer displays, entering data/issuing electronic commands, and communicating with others) can become extremely intense. It's essential to document it well, but the effort to do so may conflict with actual activity. This can be more than just annoying, as what's in the logs (or just as importantly not in them) often feeds back directly into the quality of future operations, whether short-term or long-term. In earlier programs, such as Spacelab, log keeping was done on paper, often using position-specific shorthand, and the other reader was at the mercy of the writer's penmanship. Today, user-friendly software solves the legibility problem and can automate date/time entry, but some content may take longer to finish due to individual typing speed and less use of symbols. File layout can be used to great advantage in making types of information easy to find, and creating searchable master logs for a given position is very easy and a real lifesaver in reconstructing events or researching a given topic. We'll examine log formats from several console position, and the types of information that are included and (just as importantly) excluded. We'll also look at when a summary or synopsis is effective, and when extensive detail is needed.

  3. Key factors for causing poplar Ice Nucleation Active bacterial canker and its control techniques

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The isolation, culture and the active determination of poplar ice nucleation active (INA) bacteria and the inoculation tests in laboratory and field were conducted, and the varieties, distribution and number of poplar INA bacteria and its pathogenicity and freezing injury property were determined. The study results showed that the INA bacteria widely spread on poplar in Northeast China and caused the frozen injury for poplar under the frost condition in Spring or Autumn, which was the key factor to induce INA bacterial canker. Through evaluation and investigation of different poplar varieties and inoculation tests, fine disease-resistant varieties and strains of poplar suitable for Northeast China were selected. Further tests for strong seedling showed that burying cuttings in sand and covering with plastic film could effectively avoid the frostbite, frozen and drought damage, reduce INA bacteria infection, and promote poplar growth. INA bacterial canker was detected early by highly specialized antiserums of INA bacteria and the agglutinated test of ring-shaped boundary surface. The inducers such as streptomycin, phenylmercuric acetae, salicylic acid and heat-killed bacteria to immerse cuttings, have obvious induced disease-resistant effect. Before poplar sprouted in early spring, through spraying the solution of frostbite agent, the control effect also was obvious.

  4. Vibration Reduction Methods and Techniques for Rotorcraft Utilizing On-Blade Active Control Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Rotor blades adapted for vibration control have the added benefit of extended blade and rotor life, as well as improved passenger comfort. Approaches that have been...

  5. Study on Vulnerability Exploiting and Analyzing Techniques of ActiveX Control%ActiveX控件漏洞挖掘与分析技术研究

    Institute of Scientific and Technical Information of China (English)

    黄诚; 方勇

    2012-01-01

    随着网络的快速发展,ActiveX控件的数据库访问、数据监视和图形绘制等功能,使得ActiveX控件得到了广泛的应用,而面临的安全问题也越来越严重。在研究漏洞挖掘与分析技术的基础上,对ActiveX控件安全和分析技术进行了详细研究,并结合ActiveX控件的安全问题和已有漏洞信息,设计并实现了一个Windows平台下的ActiveX控件漏洞挖掘器,弥补了现有工具对ActiveX漏洞挖掘类型不全的缺陷,并通过实例进行了验证。%With rapid development of the network, ActiveX control, for is implementing database access, data monitoring and graphing functions, is widely used, and thus faces a growing number of security problems. Based on study of vulnerability exploiting and analyzing techniques, the security and debugging techniques of ActiveX control are discussed in detail. The ActiveX control vulnerability exploiter under Windows platform is designed in combination of the inherent safety characteristics of ActiveX controls and vulnerability information, thus Making up the defects in discovering ActiveX vulnerability by existing tools. These are verified with examples

  6. Controlled and reversible induction of differentiation and activation of adult human hepatocytes by a biphasic culture technique

    Institute of Scientific and Technical Information of China (English)

    Marcus K.H. Auth; Wolf-Otto Bechstein; Roman A. Blaheta; Kim A. Boost; Kerstin Leckel; Wolf-Dietrich Beecken; Tobias Engl; Dietger Jonas; Elsie Oppermann; Philip Hilgard; Bernd H. Markus

    2005-01-01

    AIM: Clinical application of human hepatocytes (HC) is hampered by the progressive loss of growth and differentiation in vitro. The object of the study was to evaluate the effect of a biphasic culture technique on expression and activation of growth factor receptors and differentiation of human adult HC.METHODS: Isolated HC were sequentially cultured in a hormone enriched differentiation medium (DM) containing nicotinamide, insulin, transferrin, selenium, and dexamethasone or activation medium (AM) containing hepatocyte growth factor (HGF), epidermal growth factor (EGF), andgranulocyte-macrophage colony-stimulating factor (GMCSF). Expression, distribution and activation of the HC receptors (MET and EGFR) and the pattern of characteristic cytokeratin (CK) filaments were measured by fluorometry, confocal microscopy and Western blotting.RESULTS: In the biphasic culture system, HC underwent repeated cycles of activation (characterized by expression and activation of growth factor receptors) and re-differentiation (illustrated by distribution of typical filaments CK-18 but low or absent expression of CK-19). In AM increased expression of MET and EGFR was associated with receptor translocation into the cytoplasm and induction of atypical CK-19. In DM low expression of MET and EGFR was localized on the cell membrane and CK-19 was reduced. Receptor phosphorylation required embedding of HC in collagen type Ⅰ gel.CONCLUSION: Control and reversible modulation of growth factor receptor activation of mature human HC can be accomplishedin vitro, when defined signals from the extracellular matrix and sequential growth stimuli are provided. The biphasic technique helps overcome dedifferentiation, which occurs during continuous stimulation by means of growth factors.

  7. Advanced Wavefront Control Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Olivier, S S; Brase, J M; Avicola, K; Thompson, C A; Kartz, M W; Winters, S; Hartley, R; Wihelmsen, J; Dowla, F V; Carrano, C J; Bauman, B J; Pennington, D M; Lande, D; Sawvel, R M; Silva, D A; Cooke, J B; Brown, C G

    2001-02-21

    Programs at LLNL that involve large laser systems--ranging from the National Ignition Facility to new tactical laser weapons--depend on the maintenance of laser beam quality through precise control of the optical wavefront. This can be accomplished using adaptive optics, which compensate for time-varying aberrations that are often caused by heating in a high-power laser system. Over the past two decades, LLNL has developed a broad capability in adaptive optics technology for both laser beam control and high-resolution imaging. This adaptive optics capability has been based on thin deformable glass mirrors with individual ceramic actuators bonded to the back. In the case of high-power lasers, these adaptive optics systems have successfully improved beam quality. However, as we continue to extend our applications requirements, the existing technology base for wavefront control cannot satisfy them. To address this issue, this project studied improved modeling tools to increase our detailed understanding of the performance of these systems, and evaluated novel approaches to low-order wavefront control that offer the possibility of reduced cost and complexity. We also investigated improved beam control technology for high-resolution wavefront control. Many high-power laser systems suffer from high-spatial-frequency aberrations that require control of hundreds or thousands of phase points to provide adequate correction. However, the cost and size of current deformable mirrors can become prohibitive for applications requiring more than a few tens of phase control points. New phase control technologies are becoming available which offer control of many phase points with small low-cost devices. The goal of this project was to expand our wavefront control capabilities with improved modeling tools, new devices that reduce system cost and complexity, and extensions to high spatial and temporal frequencies using new adaptive optics technologies. In FY 99, the second year of

  8. Active Noise Control for Narrow-band and Broad-band Signals Using Q-Learning Technique

    Directory of Open Access Journals (Sweden)

    B. Raeisy

    2013-06-01

    Full Text Available The acoustic noise pollution is one of the serious disasters in the current industrialized life. Though traditional solutions based on noise absorption have many different applications, but these methods have low performance for low frequency noises. Active Noise Control (ANC has been introduced to resolve this problem. In this paper, a new active method is introduced for suppressing acoustic noises based on the reinforcement learning. To achieve this, an algorithm to control periodic noises is suggested. Then, the method is developed further to deal with multi-tonal signals with a large number of harmonics. At the next step, the broad-band signals are considered. The problem is broken into some sub-problems in frequency domain and each is solved via a reinforcement learning approach. In all of the proposed techniques no model for the environment is needed. Combining the reinforcement learning and the traditional methods in ANC for broad-band signals is a new line research considered here. This combination could increase the speed of the response, but some information of the dynamics of the environment is needed. This will cause the system to become compatible with gradual changes of the environment. Simulation results show the effectiveness of the proposed approach.

  9. Technique of nuclear reactors controls

    International Nuclear Information System (INIS)

    This report deal about 'Techniques of control of the nuclear reactors' in the goal to achieve the control of natural uranium reactors and especially the one of Saclay. This work is mainly about the measurement into nuclear parameters and go further in the measurement of thermodynamic variables,etc... putting in relief the new features required on behalf of the detectors because of their use in the thermal neutrons flux. In the domain of nuclear measurement, we indicate the realizations and the results obtained with thermal neutron detectors and for the measurement of ionizations currents. We also treat the technical problem of the start-up of a reactor and of the reactivity measurement. We give the necessary details for the comprehension of all essential diagrams and plans put on, in particular, for the reactor of Saclay. (author)

  10. Speed Control Of Separately Excited Dc Motor Using A High Efficiency Flyback Converter With New Active Clamp Technique M.Subramanyam*, K.Eswaramma

    Directory of Open Access Journals (Sweden)

    M.Subramanyam

    2014-10-01

    Full Text Available This paper deals with Speed control of separately excited DC motor using flyback converter with a new non complementary active clamp control method to achieve soft switching and high efficiency for heavy motor load and light load conditions. This is quite attractive for low power application with universal ac inputs, such as external adaptors. With the proposed control technique, the energy in the leakage inductance can be fully recycled. The soft switching can be achieved for the main switch and the absorbed leakage energy is transferred to the output and input side. In the Proposed model the resistive and DC motor is connected to flyback converter and it is simulated with different nominal voltages and rated speed is controlled at different levels for the N-type active clamp flyback converter and P-type active clamp flyback converter respectively. N-type active clamp flyback converter is suitable for high speed variation applications and P-type active clamp flyback converter is suitable for low speed variation applications.

  11. Design techniques for mutlivariable flight control systems

    Science.gov (United States)

    1981-01-01

    Techniques which address the multi-input closely coupled nature of advanced flight control applications and digital implementation issues are described and illustrated through flight control examples. The techniques described seek to exploit the advantages of traditional techniques in treating conventional feedback control design specifications and the simplicity of modern approaches for multivariable control system design.

  12. Suitability of the cellular viability technique as a control tool of the chlorine dosage on the activated sludge of a biological process affected by bulking

    International Nuclear Information System (INIS)

    This work demonstrates the suitability of the cellular viability technique as a control tool of the chlorine dosage on the activated sludge of a biological process affected by the overabundance of the filamentous bacteria (Thiothrix-021N). This technique was used to establish the chlorine dosage according to the observed damages on cellular membranes of both, floc-forming bacteria as well as filamentous bacteria. To identify the filamentous bacteria responsible for the macro-structural alteration of the flocs, several criteria were, met, including morphologic characteristics as well as conventional microbiological stains: Gram, Neisser and polyhydroxy alkanoates. FISH was used to confirm the obtained results, providing a definitive identification of the filamentous bacteria responsible for the alteration. (Author) 11 refs

  13. Modern insect control: Nuclear techniques and biotechnology

    International Nuclear Information System (INIS)

    The Symposium dealt primarily with genetic methods of insect control, including sterile insect technique (SIT), F1 sterility, compound chromosomes, translocations and conditional lethals. Research and development activities on various aspects of these control technologies were reported by participants during the Symposium. Of particular interest was development of F1 sterility as a practical method of controlling pest Lepidoptera. Genetic methods of insect control are applicable only on an area wide basis. They are species specific and thus do not reduce populations of beneficial insects or cause other environmental problems. Other papers presented reported on the potential use of radiation as a quarantine treatment for commodities in international trade and the use of radioisotopes as ''tags'' in studying insects

  14. Multiphase soft switched DC/DC converter and active control technique for fuel cell ripple current elimination

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Jih-Sheng (Blacksburg, VA); Liu, Changrong (Sunnyvale, CA); Ridenour, Amy (Salem, VA)

    2009-04-14

    DC/DC converter has a transformer having primary coils connected to an input side and secondary coils connected to an output side. Each primary coil connects a full-bridge circuit comprising two switches on two legs, the primary coil being connected between the switches on each leg, each full-bridge circuit being connected in parallel wherein each leg is disposed parallel to one another, and the secondary coils connected to a rectifying circuit. An outer loop control circuit that reduces ripple in a voltage reference has a first resistor connected in series with a second resistor connected in series with a first capacitor which are connected in parallel with a second capacitor. An inner loop control circuit that reduces ripple in a current reference has a third resistor connected in series with a fourth resistor connected in series with a third capacitor which are connected in parallel with a fourth capacitor.

  15. Kinetic activation-relaxation technique.

    Science.gov (United States)

    Béland, Laurent Karim; Brommer, Peter; El-Mellouhi, Fedwa; Joly, Jean-François; Mousseau, Normand

    2011-10-01

    We present a detailed description of the kinetic activation-relaxation technique (k-ART), an off-lattice, self-learning kinetic Monte Carlo (KMC) algorithm with on-the-fly event search. Combining a topological classification for local environments and event generation with ART nouveau, an efficient unbiased sampling method for finding transition states, k-ART can be applied to complex materials with atoms in off-lattice positions or with elastic deformations that cannot be handled with standard KMC approaches. In addition to presenting the various elements of the algorithm, we demonstrate the general character of k-ART by applying the algorithm to three challenging systems: self-defect annihilation in c-Si (crystalline silicon), self-interstitial diffusion in Fe, and structural relaxation in a-Si (amorphous silicon).

  16. Quality control of baby food products on the basis of results obtained using the instrumental neutron-activation analysis technique

    International Nuclear Information System (INIS)

    The purpose of this study was to use the instrumental neutron-activation analysis (INAA) to determine the elemental composition of some kind of imported baby food products (BFP) and to compare the results with the permissible contents. The nuclear reactor WWR-SM of INP has been used to develop INAA to study the mineral composition of some children's food products. The concentration of 26 trace elements, including Mg, Ca, Fe, Zn, etc. was found. The comparison of the results with regulation contents and the daily data on food needs have shown that the investigated group of BFP does not meet the requirements for all trace and macro elements composition. (authors)

  17. Weed identification using an automated active shape matching (AASM) technique

    OpenAIRE

    Swain, Kishore; Nørremark, Michael; Jørgensen, Rasmus N.; Midtiby, Henrik S.; Green, Ole

    2011-01-01

    Weed identification and control is a challenge for intercultural operations in agriculture. As an alternative to chemical pest control, a smart weed identification technique followed by mechanical weed control system could be developed. The proposed smart identification technique works on the concept of ‘active shape modelling’ to identify weed and crop plants based on their morphology. The automated active shape matching system (AASM) technique consisted of, i) a Pixelink camera ii) an LTI L...

  18. Research review: Indoor air quality control techniques

    International Nuclear Information System (INIS)

    Techniques for controlling the concentration of radon, formaldehyde, and combustion products in the indoor air are reviewed. The most effective techniques, which are generally based on limiting or reducing indoor pollutant source strengths, can decrease indoor pollutant concentrations by a factor of 3 to 10. Unless the initial ventilation rate is unusually low, it is difficult to reduce indoor pollutant concentrations more than approximately 50% by increasing the ventilation rate of an entire building. However, the efficiency of indoor pollutant control by ventilation can be enhanced through the use of local exhaust ventilation near concentrated sources of pollutants, by minimizing short circuiting of air from supply to exhaust when pollutant sources are dispersed and, in some situations, by promoting a displacement flow of air and pollutants toward the exhaust. Active air cleaning is also examined briefly. Filtration and electrostatic air cleaning for removal of particles from the indoor air are the most practical and effective currently available techniques of air cleaning. 49 refs., 7 figs

  19. Temperature Control System Using Fuzzy Logic Technique

    Directory of Open Access Journals (Sweden)

    Isizoh A N

    2012-06-01

    Full Text Available Fuzzy logic technique is an innovative technology used in designing solutions for multi-parameter and non-linear control models for the definition of a control strategy. As a result, it delivers solutions faster than the conventional control design techniques. This paper thus presents a fuzzy logic based-temperature control system, which consists of a microcontroller, temperature sensor, and operational amplifier, Analogue to Digital Converter, display interface circuit and output interface circuit. It contains a design approach that uses fuzzy logic technique to achieve a controlled temperature output function.

  20. Soft Computing Techniques for Process Control Applications

    Directory of Open Access Journals (Sweden)

    Rahul Malhotra

    2011-09-01

    Full Text Available Technological innovations in soft computing techniques have brought automation capabilities to new levelsof applications. Process control is an important application of any industry for controlling the complexsystem parameters, which can greatly benefit from such advancements. Conventional control theory isbased on mathematical models that describe the dynamic behaviour of process control systems. Due to lackin comprehensibility, conventional controllers are often inferior to the intelligent controllers. Softcomputing techniques provide an ability to make decisions and learning from the reliable data or expert’sexperience. Moreover, soft computing techniques can cope up with a variety of environmental and stabilityrelated uncertainties. This paper explores the different areas of soft computing techniques viz. Fuzzy logic,genetic algorithms and hybridization of two and abridged the results of different process control casestudies. It is inferred from the results that the soft computing controllers provide better control on errorsthan conventional controllers. Further, hybrid fuzzy genetic algorithm controllers have successfullyoptimized the errors than standalone soft computing and conventional techniques.

  1. Insect control by using sterile male technique

    International Nuclear Information System (INIS)

    The sterile male technique used in insect control is presented as an alternative for chemical control of pest insect. Description and effects of sterile male technique on morphology and physiology of different classes of pest insects are given. Prerequisite conditions necessary to work out SMT are presented. As an example of the application of this technique: control of Ephestia Cartella is studied. Gamma radiation effects on deformation, sterilization and longevity of the male insect as well as fecondity and fertility with respects of gamma irradiation are presented. 11 refs. 3 tabs

  2. Applications of neutron activation analysis technique

    International Nuclear Information System (INIS)

    The technique was developed as far back as 1936 by G. Hevesy and H. Levy for the analysis of Dy using an isotopic source. Approximately 40 elements can be analyzed by instrumental neutron activation analysis (INNA) technique with neutrons from a nuclear reactor. By applying radiochemical separation, the number of elements that can be analysed may be increased to almost 70. Compared with other analytical methods used in environmental and industrial research, NAA has some unique features. These are multi-element capability, rapidity, reproducibility of results, complementarity to other methods, freedom from analytical blank and independency of chemical state of elements. There are several types of neutron sources namely: nuclear reactors, accelerator-based and radioisotope-based sources, but nuclear reactors with high fluxes of neutrons from the fission of 235U give the most intense irradiation, and hence the highest available sensitivities for NAA. In this paper, the applications of NAA of socio-economic importance are discussed. The benefits of using NAA and related nuclear techniques for on-line applications in industrial process control are highlighted. A brief description of the NAA set-ups at CERT is enumerated. Finally, NAA is compared with other leading analytical techniques

  3. Control techniques for invasive alien plants

    Directory of Open Access Journals (Sweden)

    Michele de Sá Dechoum

    2013-03-01

    Full Text Available Invasive alien species are recognized as a major threat to the conservation of biodiversity. These species should be managed based on local and regional environmental conditions. Control techniques were tested for ten invasive species in Santa Catarina State: the trees Casuarina equisetifolia, Hovenia dulcis, Psidium guajava, Syzygium cumini, and Terminalia catappa, and shrubs and herbs Rubus fruticosus, Furcraea foetida, Hedychium coronarium, Impatiens walleriana, and Tradescantia zebrina. Treatments applied for trees were cut stump, frill and girdling or ring-barking followed by herbicide application, while the other species were treated with foliar spray, application of herbicide on the root system, cut stump and herbicide injection. The active ingredients tested were Triclopyr, Glyphosate, and the combination of Triclopyr + Fluroxipyr in concentrations from 2 to 6%, according to the species. The cut stump method was efficient for all of the woody species, while ring-barking and frilling followed by herbicide application and basal bark application resulted in different levels of efficiency for the species tested. The most efficient method for herbs and shrubs was foliar spray, and the least efficient methods were cut stump and herbicide injection.

  4. Ultrasonic techniques for process monitoring and control.

    Energy Technology Data Exchange (ETDEWEB)

    Chien, H.-T.

    1999-03-24

    Ultrasonic techniques have been applied successfully to process monitoring and control for many industries, such as energy, medical, textile, oil, and material. It helps those industries in quality control, energy efficiency improving, waste reducing, and cost saving. This paper presents four ultrasonic systems, ultrasonic viscometer, on-loom, real-time ultrasonic imaging system, ultrasonic leak detection system, and ultrasonic solid concentration monitoring system, developed at Argonne National Laboratory in the past five years for various applications.

  5. Use of nuclear techniques in biological control

    International Nuclear Information System (INIS)

    As pointed out by Benbrook (1996), pest management is at a crossroads, and there is a great need for new, biointensive pest management strategies. Among these approaches, biological control is a keystone. However, because of increasing concerns about the introduction of exotic natural enemies of insect pests and weeds (Howarth 1991, Delfosse 1997), the overall thrust of biological control has moved toward augmentative biological control, involving releases of established natural enemy species (Knipling 1992). This in turn has created a need to develop more cost-effective mass rearing technologies for beneficial insects. Nuclear techniques could play an especially important role in augmentative biological control, not only in facilitating mass rearing, but in several other ways, as indicated below. Recognising the potential value for use of nuclear techniques in biological control, the Insect and Pest Control Section of the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, sponsored a Consultants' Group Meeting on this subject in April 1997. The Group produced a document entitled Use of Nuclear Techniques in Biological Control: Managing Pests, Facilitating Trade and Protecting the Environment. The consultants included the authors of this paper as well as Ernest Delfosse (at that time, with the USDA-APHIS National Biological Control Institute), Garry Hill (Intl. Institute for Biological Control), Sinthya Penn (Beneficial Insectary), and Felipe Jeronimo (USDA-APHIS PPQ, Guatemala). The remarks presented in this paper reflect the thoughts presented by these consultants and other participants at the IAEA-sponsored meeting. Several potential uses for nuclear techniques were identified by the Consultants' Group, including: 1) improvements in rearing media (either artificial diets or natural hosts/prey), 2) provision of sterilised natural prey to be used as food during shipment, to ameliorate concerns relating to the

  6. Active learning techniques for librarians practical examples

    CERN Document Server

    Walsh, Andrew

    2010-01-01

    A practical work outlining the theory and practice of using active learning techniques in library settings. It explains the theory of active learning and argues for its importance in our teaching and is illustrated using a large number of examples of techniques that can be easily transferred and used in teaching library and information skills to a range of learners within all library sectors. These practical examples recognise that for most of us involved in teaching library and information skills the one off session is the norm, so we need techniques that allow us to quickly grab and hold our

  7. Active noise control primer

    CERN Document Server

    Snyder, Scott D

    2000-01-01

    Active noise control - the reduction of noise by generating an acoustic signal that actively interferes with the noise - has become an active area of basic research and engineering applications. The aim of this book is to present all of the basic knowledge one needs for assessing how useful active noise control will be for a given problem and then to provide some guidance for designing, setting up, and tuning an active noise-control system. Written for students who have no prior knowledge of acoustics, signal processing, or noise control but who do have a reasonable grasp of basic physics and mathematics, the book is short and descriptive. It leaves for more advanced texts or research monographs all mathematical details and proofs concerning vibrations, signal processing and the like. The book can thus be used in independent study, in a classroom with laboratories, or in conjunction with a kit for experiment or demonstration. Topics covered include: basic acoustics; human perception and sound; sound intensity...

  8. Active interaction control for civil structures

    OpenAIRE

    Wang, Luo-Jia

    1997-01-01

    This thesis presents a civil engineering approach to active control for civil structures. The proposed control technique, termed Active Interaction Control (AIC), utilizes dynamic interactions between different structures, or components of the same structure, to reduce the resonance response of the controlled or primary structure under earthquake excitations. The primary control objective of AIC is to minimize the maximum story drift of the primary structure. This is accomplished by timing th...

  9. Admission Control Techniques for UMTS System

    Directory of Open Access Journals (Sweden)

    P. Kejik

    2010-09-01

    Full Text Available Universal mobile telecommunications system (UMTS is one of the 3rd generation (3G cell phone technologies. The capacity of UMTS is interference limited. Radio resources management (RRM functions are therefore used. They are responsible for supplying optimum coverage, ensuring efficient use of physical resources, and providing the maximum planned capacity. This paper deals with admission control techniques for UMTS. An own UMTS simulation program and several versions of proposed admission control algorithms are presented in this paper. These algorithms are based on fuzzy logic and genetic algorithms. The performance of algorithms is verified via simulations.

  10. Control techniques for invasive alien plants

    OpenAIRE

    Michele de Sá Dechoum; Sílvia Renate Ziller

    2013-01-01

    Invasive alien species are recognized as a major threat to the conservation of biodiversity. These species should be managed based on local and regional environmental conditions. Control techniques were tested for ten invasive species in Santa Catarina State: the trees Casuarina equisetifolia, Hovenia dulcis, Psidium guajava, Syzygium cumini, and Terminalia catappa, and shrubs and herbs Rubus fruticosus, Furcraea foetida, Hedychium coronarium, Impatiens walleriana, and Tradescantia zebrina. T...

  11. OOP techniques for control systems software design

    International Nuclear Information System (INIS)

    The process of software design for nuclear power plants has several stages that must be fulfilled for a successful application. The first deals with the suitability of the concepts being applied to control the process itself, i.e. the control theory approach used, rationale for imposed limits, etc., that could be termed the formal specification generation. The second encompasses the processes of insuring the correctness of the software according to its formal specification. There are several approaches to dealing with these issues being developed worldwide, from the purely analytical to exhaustive testing methods. The purpose of our research effort is to explore and develop new tools for designing and testing control algorithms based in object-oriented programming (OOP) techniques and iconic interfaces. These two technologies will empower the designer by providing powerful yet simple means to introduce faults, investigate their effects and introduce configuration changes. Software development approaches that both encourage and force modularity with explicit interfacing definition could be of great help towards automatic software verification techniques. It is in this context that OOP techniques could play an important role, since they could be thought of as independent units interacting through allowed communication channels. Object classes implementing most common algorithms have been developed and used in our research laboratory computing environment with good results. It is feasible, in principle at least, to design a topology advisor/verifier that parses the control algorithm to detect anomalous configurations. Future research topics include the development of a prototype topology parser to explore its potential applicability in software design. (Author) 6 refs., 2 figs

  12. Active load control using microtabs

    Science.gov (United States)

    Yen, Dora Te-Lun

    2001-11-01

    Micro-electro-mechanical (MEM) translational tabs are introduced for enhancing and controlling the aerodynamic loading on lifting surfaces. These microtabs are mounted near the trailing edge of lifting surfaces, retract and extend approximately normal to the surface and have a maximum deployment height on the order of the boundary-layer thickness. Deployment of the device effectively modifies the camber distribution of the lifting surface and hence, the lift generated. The effect of the microtabs on lift is shown to be as powerful as conventional control surfaces with lift changes of 30%--50% in the linear range of the lift curve using a tab with a height of 1% of airfoil chord placed at 5% of chord upstream of the trailing edge on the lower surface. A multi-disciplinary approach incorporating aspects of experimental and computational aerodynamics, mechanical design and microfabrication techniques has been taken to develop and test a "proof of concept" model. Flow simulations, using a Reynolds-averaged Navier Stokes solver, have been conducted to optimize the size and placement of the devices based on trailing edge volume constraints. Numerical and experimental wind tunnel results are in good agreement, and both confirm that these micro-scale devices create macro-scale changes in aerodynamic loading. Application of this rather simple but innovative lift control system based on microfabrication techniques introduces a robust, dynamic control device and will allow for the miniaturization of conventional high lift and control systems. The result is a significant reduction in typical control system weight, complexity and cost. Also due to the minute size of these tabs, their activation and response times are much faster than that of conventional trailing edge devices. The "proof of concept" tab design, fabrication techniques, computational and experimental setup, and test results using a representative airfoil are presented in this research. (For more information, see

  13. Concurrency Control Technique in RFID Implementation

    Directory of Open Access Journals (Sweden)

    Ajaegbu C

    2014-03-01

    Full Text Available Database techniques have been used to proffer solution to some challenging situations that has to do with management of data in industries. This idea can also be valuable and implemented in managing the operation mode of some devices during t he design level stage. The proposition of Radio Frequency Identification Detection technology as a convenient and automatic instrument of identification and detection has shown value in usage in the society. However, it has been identified with some challenges such as collision despite its prospects. The need to mitigate collision between a reader and multiple tags is of importance for effective deployment of the technology. The paper aimed at integrating one of the concepts of database management technique of concurrency control known as Time-Stamp (TS in order to offer solution to the problem of collision in RFID implementation. This paper adopted a small scale business scenario which was used to illustrate the benefit this stands to offer in the real-life implementation. The paper concluded by arguing that this technique can be adopted and implemented and by such doing, will enhance further the performance of RFID technology.

  14. CONCURRENCY CONTROL TECHNIQUE IN RFID IMPLEMENTATION

    Directory of Open Access Journals (Sweden)

    Ajaegbu C

    2015-11-01

    Full Text Available Database techniques have been used to proffer solution to some challenging situations that has to do with management of data in industries. This idea can also be valuable and implemented in managing the operation mode of some devices during the design level stage. The proposition of Radio Frequency Identification Detection technology as a convenient and automatic instrument of identification and detection has shown value in usage in the society. However, it has been identified with some challenges such as collision despite its prospects. The need to mitigate collision between a reader and multiple tags is of importance for effective deployment of the technology. The paper aimed at integrating one of the concepts of database management technique of concurrency control known as Time-Stamp (TS in order to offer solution to the problem of collision in RFID implementation. This paper adopted a small scale business scenario which was used to illustrate the benefit this stands to offer in the real-life implementation. The paper concluded by arguing that this technique can be adopted and implemented and by such doing, will enhance further the performance of RFID technology.

  15. Improvement of vibration and noise by applying analysis technology. Development of active control technique of engine noise in a car cabin. Kaiseki gijutsu wo oyoshita shindo-soon no kaizen. Shashitsunai engine soon akutibu seigyo gijutsu no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, H.; Nakao, N.; Butsuen, T. (Matsuda Motor Corp., Hiroshima (Japan). Technology Research Inst.)

    1994-06-01

    It is difficult to reduce engine noise which is principal noise in a car cabin without producing an adverse effect on low cost production. Active noise control technique (ANC) has been developed to reduce engine noise compatible with low cost production. This paper discusses its control algorithm and the system configuration and presents experimental results. The filtered-x least mean square method is a well-known ANC algorithm, however, it often requires large amount of calculation exceeding the present capacity of a digital signal processor. An effective ANC algorithm is developed by the use of the repetitiveness of the engine noise. This paper describes the basic theory of the control algorithm, the extension to a multiple input and output system, the system configuration and experimental results. A noise control system with three microphones is designed with consideration of the spatial distribution of the noise and reduces noise in the whole cabin by 8dB(A) in the largest case. Active noise control technique is applicable to many areas and can be used for the reduction of noise and vibration other than engine noise. 5 refs., 7 figs., 1 tab.

  16. Escherichia coli activity characterization using a laser dynamic speckle technique

    CERN Document Server

    Ramírez-Miquet, Evelio E; Contreras-Alarcón, Orestes R

    2012-01-01

    The results of applying a laser dynamic speckle technique to characterize bacterial activity are presented. The speckle activity was detected in two-compartment Petri dishes. One compartment was inoculated and the other one was left as a control blank. The speckled images were processed by the recently reported temporal difference method. Three inoculums of 0.3, 0.5, and 0.7 McFarland units of cell concentration were tested; each inoculum was tested twice for a total of six experiments. The dependences on time of the mean activity, the standard deviation of activity and other descriptors of the speckle pattern evolution were calculated for both the inoculated compartment and the blank. In conclusion the proposed dynamic speckle technique allows characterizing the activity of Escherichia coli bacteria in solid medium.

  17. Active Correlation Technique: Status and Development

    CERN Document Server

    Tsyganov, Yury

    2015-01-01

    During the recent years, at the FLNR a successful cycle of experiments has been accomplished on the synthesis of the superheavy elements with Z=112 to Z=118 using 48Ca ion beam. From the viewpoint of the detection of rare decays and background suppression, this success was achieved due to the application of a new radical technique, the method of active correlations. The method employs search in a real time mode for a pointer to a probable correlation like recoil alpha for switching the beam off. In the case of detection in the same detector strip an additional alpha decay event, of beam OFF time interval is prolonged automatically

  18. Performance Comparison of Active Queue Management Techniques

    Directory of Open Access Journals (Sweden)

    T. B. Reddy

    2008-01-01

    Full Text Available Congestion is an important issue which researchers focus on in the Transmission Control Protocol (TCP network environment. To keep the stability of the whole network, congestion control algorithms have been extensively studied. Queue management method employed by the routers is one of the important issues in the congestion control study. Active Queue Management (AQM has been proposed as a router-based mechanism for early detection of congestion inside the network. In this study, we are comparing AQM two popular queue management methods, Random Early Detection (RED and droptail, in different aspects, such as throughput and fairness Index. The comparison results indicate RED performed slightly better with higher throughput and higher fairness Index than droptail. Simulation is done by using Network Simulator (NS2 and the graphs are drawn using X- graph.

  19. Sterile insect technique in codling moth control

    International Nuclear Information System (INIS)

    Exposure of mature pupae or adult codling moths, Cydia pomonella (L.), to 30-40 krad of gamma radiation induces a high level of sterility in the male and complete sterility in the female without seriously affecting behaviour except for sperm competitiveness which is drastically reduced. Substerilizing doses (below about 25 krad) have very little adverse effect and induces higher level of sterility in the F1 male than in the irradiated male parent. The most satisfactory method of measuring the population density of native moths is by examining fruit for larval exit holes. Population increase per generation depends largely on evening temperatures during the moth's reproductive period. The codling moth is a sedentary species, and its distribution is very uneven in commercial orchards. Neglected host trees must be sprayed or destroyed to avoid reinfestation of sterile insect release orchards with immigrant moths. Laboratory-reared moths may be marked externally with fluorescent powders or internally with calco oil red without adverse effects. Mass rearing is still unreliable and expensive, and prolonged colonization affects the insects' behaviour. Successful codling moth suppression was achieved in North America and/or Europe by release of sterile males, sterile females or sterile mixed sexes; by substerile males; and by F1 male progeny (released as diapausing larvae) of substerile males X untreated females. Arthropod predators and parasites held aphids and spider mites at noninjurious levels in most insect release orchards, but leafrollers eventually built up to damaging numbers. The sterile insect technique for commercial control of the codling moth is not feasible at this time because of high costs. (author)

  20. Landfill pollution control with isotope techniques

    International Nuclear Information System (INIS)

    Groundwater and surface water contamination by sanitary landfills is being monitored since 1989 in Italy by using isotope techniques combined with chemical analyses. The results obtained are considered mostly satisfactory for identifying sources of contaminants and predicting their behaviour. We present in this work the results of chemical and isotopic measurements performed on rainwater, surface water and groundwater samples, with the aim of investigating the fate of contaminants released from some landfills located near Ancona, Central Italy. The isotope determinations included δ18O, δ2H and tritium (3H). The first objective of these investigations is establishing the background values of the main environmental parameters related to contamination, and obtaining indication about source and residence time (age) of groundwater in the landfill proximity. In particular, the methods used for detecting groundwater and/or surface waters contamination derived from the landfill, are based on the occurrence of tritium activity anomalies and chemical concentration changes. In order to estimate the regional background of environmental tritium in shallow groundwater, we measured the tritium content of monthly rainwater samples collected in stations on the Apennines in proximity of Ancona. The tritium concentration ranged from 3 to 6 TU in winter months (October to April), and reached the maximum values (up to 14 TU) in summer months. The investigations of groundwater and surface water contamination were undertaken on landfills dismissed from 1986 to 1998. The isotopic and chemical monitoring was started one year ago and was carried out on leachates, surface waters and groundwater (the last sampled in several downstream wells). The tritium concentration in leachates can be very high, due to a still active tritium release from the landfill. Tritium values in wells outside of the landfill area, lower than in leachate but higher than the regional background of environmental

  1. Efficiency in Controlling Activities

    OpenAIRE

    Van Nguyen, Tuyen

    2015-01-01

    Controlling is essential for financial success of corporations. An efficient controlling system should be implemented in order to manage financial performance from income, expense to profitability. The purpose of the thesis is to provide insight knowledge towards corporate accounting management as well as to propose potential improvement for the existing controlling system of the case company, which is Bosch Rexroth Japan. The theoretical framework creates the knowledge foundation for re...

  2. Control of nucleus accumbens activity with neurofeedback

    OpenAIRE

    Greer, Stephanie M.; Trujillo, Andrew J.; Glover, Gary H.; Knutson, Brian

    2014-01-01

    The nucleus accumbens (NAcc) plays critical roles in healthy motivation and learning, as well as in psychiatric disorders (including schizophrenia and attention deficit hyperactivity disorder). Thus, techniques that confer control of NAcc activity might inspire new therapeutic interventions. By providing second-to-second temporal resolution of activity in small subcortical regions, functional magnetic resonance imaging (fMRI) can resolve online changes in NAcc activity, which can then be pres...

  3. Active control of convection

    Energy Technology Data Exchange (ETDEWEB)

    Bau, H.H. [Univ. of Pennsylvania, Philadelphia, PA (United States)

    1995-12-31

    Using stability theory, numerical simulations, and in some instances experiments, it is demonstrated that the critical Rayleigh number for the bifurcation (1) from the no-motion (conduction) state to the motion state and (2) from time-independent convection to time-dependent, oscillatory convection in the thermal convection loop and Rayleigh-Benard problems can be significantly increased or decreased. This is accomplished through the use of a feedback controller effectuating small perturbations in the boundary data. The controller consists of sensors which detect deviations in the fluid`s temperature from the motionless, conductive values and then direct actuators to respond to these deviations in such a way as to suppress the naturally occurring flow instabilities. Actuators which modify the boundary`s temperature/heat flux are considered. The feedback controller can also be used to control flow patterns and generate complex dynamic behavior at relatively low Rayleigh numbers.

  4. Improvement of controlled pollination techniques of poplar

    Institute of Scientific and Technical Information of China (English)

    ZHOU Zhong-cheng; LIU Zong-you; HOU Kai-ju; SUN Xian-meng; ZHANG Ji-he; SHEN Bao-xian

    2008-01-01

    Over a number of years, in order to find substitutes for two traditional poplar pollination techniques: outdoor bridging trees and indoor cutting with water culture, research into two new pollination methods of uprooted outdoor seed trees and outdoor cutting branches was carried out. The advantages of two new and improved techniques were of efficiency, economy, safety and ease of operation. The methods can be applied in hybridization and breeding of poplar and other easy-to-root trees.

  5. Two applications of airtightness control techniques on big assemblies

    CERN Document Server

    Devallan, C; Marcellin, J

    1973-01-01

    Deals with two airtightness control techniques respectively applied on intersecting storage rings (ISR) at CERN in Geneva and on a liquid methane storage tank. These two big assemblies called for two different control techniques which use helium and ammonia respectively as tracer gas. Existing practical leakage detection techniques to meet industrial needs are discussed at the end of the article. (2 refs).

  6. Active Combustion Control Valve Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Over the past decade, research into active combustion control has yielded impressive results in suppressing thermoacoustic instabilities and widening the...

  7. Active Control of Suspension Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this paper some recent research on active control of very long suspension bridges, is presented. The presentation is based on research work at Aalborg University, Denmark. The active control system is based on movable flaps attached to the bridge girder. Wind load on bridges with or without...... flaps attached to the girder is briefly presented. A simple active control system is discussed. Results from wind tunnel experiments with a bridge section show that flaps can be used effectively to control bridge girder vibrations. Flutter conditions for suspension bridges with and without flaps...

  8. 主动噪声控制技术在工业换风扇降噪中的应用%Application of Active Noise Control Technique in Noise Reduction System of Industrial Exhaust Fan

    Institute of Scientific and Technical Information of China (English)

    吴亚锋; 姜节胜; 张森社

    2001-01-01

    The noise of exhaust fan is mainly consisted of pass frequency & low second harmonic frequency when blade is rotating. Noises on discrete frequency can be efficiently controled by using active noise control technique. A self control system which has 4 error input & 2 counteracting output is designed by the author. The satisfied result is obtained by using it on noise control system of exhaust fan.%指出了换风扇噪声主要是由风叶旋转时的通频及其低次谐频成分构成,应用主动噪声控制技术能够有效地抑制这些离散频率上的声音。笔者设计了一具有4个误差输入和两个抵消输出的自适应控制系统,并应用于换风扇噪声控制上,获得了满意的实验结果。

  9. Demand Management Based on Model Predictive Control Techniques

    Directory of Open Access Journals (Sweden)

    Yasser A. Davizón

    2014-01-01

    Full Text Available Demand management (DM is the process that helps companies to sell the right product to the right customer, at the right time, and for the right price. Therefore the challenge for any company is to determine how much to sell, at what price, and to which market segment while maximizing its profits. DM also helps managers efficiently allocate undifferentiated units of capacity to the available demand with the goal of maximizing revenue. This paper introduces control system approach to demand management with dynamic pricing (DP using the model predictive control (MPC technique. In addition, we present a proper dynamical system analogy based on active suspension and a stability analysis is provided via the Lyapunov direct method.

  10. Advanced Control Techniques for WEC Wave Dragon

    DEFF Research Database (Denmark)

    Tedd, James; Kofoed, Jens Peter; Jasinski, M.;

    2007-01-01

    This paper presents the ongoing work on control of the Wave Dragon wave energy converter. Research is being conducted in and between several centers across Europe. This is building upon the knowledge gained in the prototype project, and will enable much better performance of the future deployment...... of the full scale Wave Dragon....

  11. Advanced Control Techniques for WEC Wave Dragon

    OpenAIRE

    Tedd, James; Kofoed, Jens Peter; Jasinski, M; Morris, A.; Friis-Madsen, E.; Wisniewski, Rafal; Bendtsen, Jan Dimon

    2007-01-01

      This paper presents the ongoing work on control of the Wave Dragon wave energy converter. Research is being conducted in and between several centers across Europe. This is building upon the knowledge gained in the prototype project, and will enable much better performance of the future deployment of the full scale Wave Dragon.

  12. Benchmark of experimental techniques for measuring and controlling suction

    OpenAIRE

    Muñoz, Juan Jorge; Tarantino, A.; Gallipoli, Domenico; Augarde, C.E.; V. Gennaro; Gómez, R.; Laloui, L.; Mancuso, C.; El Mountassir, G.; Wheeler, S. J.; Tombolato, S.; Toll, D.G.; Rojas Arias, Juan Carlos; Raveendiraraj, A.; Romero Morales, Enrique Edgar

    2011-01-01

    The paper presents a benchmarking study carried out within the ‘Mechanics of Unsaturated Soils for Engineering’ (MUSE) network aimed at comparing different techniques for measurement and control of suction. Techniques tested by the eight ‘Mechanics of Unsaturated Soils for Engineering’ research teams include axis-translation (pressure plate and suction-controlled oedometer), highcapacity tensiometer and osmotic technique. The soil used in the exercise was a mixture of uniform sand, sodium ...

  13. Technique for Controlling Spread of Limnotic Oncomelania

    Institute of Scientific and Technical Information of China (English)

    Li Damei(李大美); WANG Xiangsan(王祥三); LAI Yonggen

    2003-01-01

    Schistosomiasis is a parasitic disease mostly found in areas along the Changjiang River of China. The disease is spread solely through an intermediary named oncomelania, so its spread of schistosomiasis can be controlled by properly designing water intakes which prevent oncomelania from entering fanning land or residential areas. This paper reports a successful design process and a new oncomelania-free intake device. The design of the new intake is based on a sound research program in which extensive experimental studies were carried out to gain knowledge of oncomelania eco-hydraulic behavior and detailed flow field information through CFD simulation.

  14. Sterile insect technique for tsetse control and eradication

    International Nuclear Information System (INIS)

    The current publication contains the contributions made by scientists who participated in the fourth Co-ordinated Research Programme. A range of topics, covering both field and laboratory activities, was addressed: Eradication of Glossina palpalis palpalis (Robineau-Desvoidy) (Diptera: Glossinidae) from agropastoral land in Central Nigeria by means of the sterile insect technique; Research and development in the IAEA Laboratory at Seibersdorf in support of BICOT for the eradication of Glossina palpalis palpalis; Tsetse fly eradication in Burkina Faso and evaluation of traps and targets; Ecology of Glossina species inhabiting peridomestic agroecosystems in relation to options for tsetse fly control; Population dynamics of Glossina fuscipes fuscipes on Buvuma Island, Lake Victoria, Uganda; Population estimation from mark-recapture data: Equations for a pooled mark system and for pooled data, with applications to a study on island populations of tsetse flies in Zimbabwe; Surveillance of tsetse fly and cattle populations for trypanosomes in the BICOT area during the sterile insect technique control programme; Freeze dried blood and development of an artificial diet for blood feeding anthropods; Effects of the nutritional quality of locally obtained blood diets on the performance of Glossina palpalis palpalis fed in vitro; Mycetomes and symbionts of tsetse flies maintained on a membrane feeding system and the agents interfering with natural reproduction; Virus particles infection in laboratory reared Glossina pallidipes Austen (Diptera: Glossinidae); Influence of different nutritional sources on haemolymph composition and vitellogenesis in haematophagous arthropods; Effect of rearing diet on the injection rate in flies released for the control of tsetse populations by sterile males; Use of juvenile hormone mimics in the sterilization of tsetse flies; Studies of Glossina pallidipes and G. morsitans subspecies related to the genetic control of tsetse flies

  15. A comparison between active and passive techniques for measurements of radon emanation factors

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Coto, I. [Dept. Fisica Aplicada, University of Huelva, Huelva (Spain)], E-mail: Israel.lopez@dfa.uhu.es; Mas, J.L. [Dept. de Fisica Aplicada I, E.U.P., University of Seville, Seville (Spain); San Miguel, E.G.; Bolivar, J.P. [Dept. Fisica Aplicada, University of Huelva, Huelva (Spain); Sengupta, D. [Department of Geology and Geophysics, I.I.T. Kharagpur, West Bengal (India)

    2009-05-15

    Some radon related parameters have been determined through two different techniques (passive and active) in soil and phosphogypsum samples. Emanation factors determined through these techniques show a good agreement for soil samples while for phosphogympsum samples appear large discrepancies. In this paper, these discrepancies are analyzed and explained if non-controlled radon leakages in the passive technique are taken into account.

  16. Power system stabilizers based on modern control techniques

    Energy Technology Data Exchange (ETDEWEB)

    Malik, O.P.; Chen, G.P.; Zhang, Y.; El-Metwally, K. [Calgary Univ., AB (Canada). Dept. of Electrical and Computer Engineering

    1994-12-31

    Developments in digital technology have made it feasible to develop and implement improved controllers based on sophisticated control techniques. Power system stabilizers based on adaptive control, fuzzy logic and artificial networks are being developed. Each of these control techniques possesses unique features and strengths. In this paper, the relative performance of power systems stabilizers based on adaptive control, fuzzy logic and neural network, both in simulation studies and real time tests on a physical model of a power system, is presented and compared to that of a fixed parameter conventional power system stabilizer. (author) 16 refs., 45 figs., 3 tabs.

  17. Optical control of antibacterial activity

    Science.gov (United States)

    Velema, Willem A.; van der Berg, Jan Pieter; Hansen, Mickel J.; Szymanski, Wiktor; Driessen, Arnold J. M.; Feringa, Ben L.

    2013-11-01

    Bacterial resistance is a major problem in the modern world, stemming in part from the build-up of antibiotics in the environment. Novel molecular approaches that enable an externally triggered increase in antibiotic activity with high spatiotemporal resolution and auto-inactivation are highly desirable. Here we report a responsive, broad-spectrum, antibacterial agent that can be temporally activated with light, whereupon it auto-inactivates on the scale of hours. The use of such a ‘smart’ antibiotic might prevent the build-up of active antimicrobial material in the environment. Reversible optical control over active drug concentration enables us to obtain pharmacodynamic information. Precisely localized control of activity is achieved, allowing the growth of bacteria to be confined to defined patterns, which has potential for the development of treatments that avoid interference with the endogenous microbial population in other parts of the organism.

  18. Demonstration of Active Combustion Control

    Science.gov (United States)

    Lovett, Jeffrey A.; Teerlinck, Karen A.; Cohen, Jeffrey M.

    2008-01-01

    The primary objective of this effort was to demonstrate active control of combustion instabilities in a direct-injection gas turbine combustor that accurately simulates engine operating conditions and reproduces an engine-type instability. This report documents the second phase of a two-phase effort. The first phase involved the analysis of an instability observed in a developmental aeroengine and the design of a single-nozzle test rig to replicate that phenomenon. This was successfully completed in 2001 and is documented in the Phase I report. This second phase was directed toward demonstration of active control strategies to mitigate this instability and thereby demonstrate the viability of active control for aircraft engine combustors. This involved development of high-speed actuator technology, testing and analysis of how the actuation system was integrated with the combustion system, control algorithm development, and demonstration testing in the single-nozzle test rig. A 30 percent reduction in the amplitude of the high-frequency (570 Hz) instability was achieved using actuation systems and control algorithms developed within this effort. Even larger reductions were shown with a low-frequency (270 Hz) instability. This represents a unique achievement in the development and practical demonstration of active combustion control systems for gas turbine applications.

  19. Hybrid control using evolutionary tuned fuzzy controller techniques - a study

    OpenAIRE

    Stirrup, R.; Chipperfield, A.; Tang, K.S.; Man, K.F.

    2002-01-01

    Many real world systems exist that have operating regions or regimes that exhibit varying degrees of non-lineararity. An example of this are the significant variations in the dynamic characteristics of a distributed collector field within a solar power plant. Her a gain schedule controller using pole placement with feedforward was chosen to control the more linear operating regimes of the plant. Then a study was carried out to find the best suited and most efficient evolutionary-tuned fuzz...

  20. ABOUT CONTROLLING OF SCIENTIFIC ACTIVITY

    Directory of Open Access Journals (Sweden)

    Mukhin V. V.

    2014-06-01

    Full Text Available We have selected the new area of controlling - scientific activity controlling. We consider some problems of development in this field, primarily the problem of selection of key performance indicators. It’s been founded that administrative measures stimulated the pursuit of a number of articles published in scientific journals hinders the development of science. Methodological errors - emphasis on citation indexes, impact factors, etc. - lead to wrong management decisions. As the experience of the UK, an expertise should be applied in the management of science. The article briefly discusses some of the drawbacks of the system of scientific specialties. It is proposed to expand research on the science of science and scientific activity controlling. We have also discussed the problems of controlling in applied research organizations

  1. Model-free control techniques for Stop & Go systems

    OpenAIRE

    Villagra, Jorge; Milanés, Vicente; Pérez Rastelli, Joshué; González, Carlos

    2010-01-01

    International audience; This paper presents a comparison of Stop & Go control algorithms, which deal with car following scenarios in urban environments. Since many vehicle/road interaction factors (road slope, aerodynamic forces) and actuator dynamics are very poorly known, two robust control strategies are proposed: an intelligent PID controller and a fuzzy controller. Both model-free techniques will be implemented and compared in simulation to show their suitability for demanding scenarios.

  2. Simulation studies for multichannel active vibration control

    Science.gov (United States)

    Prakash, Shashikala; Balasubramaniam, R.; Praseetha, K. K.

    2003-10-01

    Traditional approach to vibration control uses passive techniques, which are relatively large, costly and ineffective at low frequencies. Active Vibration Control (AVC) is used to overcome these problems & in AVC additional sources (secondary) are used to cancel vibration from primary source based on the principle of superposition theorem Since the characteristics of the vibration source and environment are time varying, the AVC system must be adaptive. Adaptive systems have the ability to track time varying disturbances and provide optimal control over a much broader range of conditions than conventional fixed control systems. In multi channel AVC vibration fields in large dimensions are controlled & is more complicated. Therefore to actively control low frequency vibrations on large structures, multi channel AVC requires a control system that uses multiple secondary sources to control the vibration field simultaneously at multiple error sensor locations. The error criterion that can be directly measured is the sum of squares of outputs of number of sensors. The adaptive algorithm is designed to minimize this & the algorithm implemented is the "Multiple error LMS algorithm." The best known applications of multiple channel FXLMS algorithm is in real time AVC and system identification. More wider applications are in the control of propeller induced noise in flight cabin interiors. In the present paper the results of simulation studies carried out in MATLAB as well as on TMS320C32 DSP processor will be brought out for a two-channel case.

  3. Learning by Doing: An Empirical Study of Active Teaching Techniques

    Science.gov (United States)

    Hackathorn, Jana; Solomon, Erin D.; Blankmeyer, Kate L.; Tennial, Rachel E.; Garczynski, Amy M.

    2011-01-01

    The current study sought to examine the effectiveness of four teaching techniques (lecture, demonstrations, discussions, and in-class activities) in the classroom. As each technique offers different benefits to the instructor and students, each technique was expected to aid in a different depth of learning. The current findings indicated that each…

  4. Active control: Wind turbine model

    DEFF Research Database (Denmark)

    Bindner, H.

    1999-01-01

    validation as well as parameter estimation. The model includes a simple model of the structure of the turbine including tower and flapwise blade bending,a detailed model of the gear box and induction generator, a linearized aerodynamic model including modelling of induction lag and actuator and sensor models......This report is a part of the reporting of the work done in the project 'Active Control of Wind Turbines'. This project aim is to develop a simulation model for design of control systems for turbines with pitch control and to use that model to designcontrollers. This report describes the model...... developed for controller design and analysis. Emphasis has been put on establishment of simple models describing the dynamic behavior of the wind turbine in adequate details for controller design. This hasbeen done with extensive use of measurements as the basis for selection of model complexity and model...

  5. Handwashing Technique. Instructor's Packet. Learning Activity Package.

    Science.gov (United States)

    Stark, Pamela

    This instructor's packet accompanies the learning activity package (LAP) on handwashing. Contents included in the packet are a time sheet, suggested uses for the LAP, an instruction sheet, final LAP reviews, a final LAP review answer key, a student performance checklist, an additional resources list, and student completion cards to issue to…

  6. Engine control techniques to account for fuel effects

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Shankar; Frazier, Timothy R.; Stanton, Donald W.; Xu, Yi; Bunting, Bruce G.; Wolf, Leslie R.

    2014-08-26

    A technique for engine control to account for fuel effects including providing an internal combustion engine and a controller to regulate operation thereof, the engine being operable to combust a fuel to produce an exhaust gas; establishing a plurality of fuel property inputs; establishing a plurality of engine performance inputs; generating engine control information as a function of the fuel property inputs and the engine performance inputs; and accessing the engine control information with the controller to regulate at least one engine operating parameter.

  7. Nonlinear control techniques for an atomic force microscope system

    Institute of Scientific and Technical Information of China (English)

    Yongchun FANG; Matthew FEEMSTER; Darren DAWSON; Nader M.JALILI

    2005-01-01

    Two nonlinear control techniques are proposed for an atomic force microscope system.Initially,a learning-based control algorithm is developed for the microcantilever-sample system that achieves asymptotic cantilever tip tracking for periodic trajectories.Specifically,the control approach utilizes a learning-based feedforward term to compensate for periodic dynamics and high-gain terms to account for non-periodic dynamics.An adaptive control algorithm is then developed to achieve asymptotic cantilever tip tracking for bounded tip trajectories despite uncertainty throughout the system parameters.Simulation results are provided to illustrate the efficacy and performance of the control strategies.

  8. Sliding mode control of switching power converters techniques and implementation

    CERN Document Server

    Tan, Siew-Chong; Tse, Chi-Kong

    2011-01-01

    Sliding Mode Control of Switching Power Converters: Techniques and Implementation is perhaps the first in-depth account of how sliding mode controllers can be practically engineered to optimize control of power converters. A complete understanding of this process is timely and necessary, as the electronics industry moves toward the use of renewable energy sources and widely varying loads that can be adequately supported only by power converters using nonlinear controllers.Of the various advanced control methods used to handle the complex requirements of power conversion systems, sliding mode c

  9. Input techniques that dynamically change their cursor activation area

    DEFF Research Database (Denmark)

    Hertzum, Morten; Hornbæk, Kasper

    2007-01-01

    Efficient pointing is crucial to graphical user interfaces, and input techniques that dynamically change their activation area may yield improvements over point cursors by making objects selectable at a distance. Input techniques that dynamically change their activation area include the bubble...... cursor, whose activation area always contains the closest object, and two variants of cell cursors, whose activation areas contain a set of objects in the vicinity of the cursor. We report two experiments that compare these techniques to a point cursor; in one experiment participants use a touchpad...... for operating the input techniques, in the other a mouse. In both experiments, the bubble cursor is fastest and participants make fewer errors with it. Participants also unanimously prefer this technique. For small targets, the cell cursors are generally more accurate than the point cursor; in the second...

  10. Novel Active Combustion Control Valve

    Science.gov (United States)

    Caspermeyer, Matt

    2014-01-01

    This project presents an innovative solution for active combustion control. Relative to the state of the art, this concept provides frequency modulation (greater than 1,000 Hz) in combination with high-amplitude modulation (in excess of 30 percent flow) and can be adapted to a large range of fuel injector sizes. Existing valves often have low flow modulation strength. To achieve higher flow modulation requires excessively large valves or too much electrical power to be practical. This active combustion control valve (ACCV) has high-frequency and -amplitude modulation, consumes low electrical power, is closely coupled with the fuel injector for modulation strength, and is practical in size and weight. By mitigating combustion instabilities at higher frequencies than have been previously achieved (approximately 1,000 Hz), this new technology enables gas turbines to run at operating points that produce lower emissions and higher performance.

  11. Evolutionary biology and genetic techniques for insect control

    OpenAIRE

    Leftwich, Philip; Bolton, Michael; Chapman, Tracey

    2016-01-01

    Abstract The requirement to develop new techniques for insect control that minimize negative environmental impacts has never been more pressing. Here we discuss population suppression and population replacement technologies. These include sterile insect technique, genetic elimination methods such as the release of insects carrying a dominant lethal (RIDL), and gene driving mechanisms offered by intracellular bacteria and homing endonucleases. We also review the potential of newer or underutil...

  12. Metamodeling Techniques Applied to the Design of Reconfigurable Control Applications

    Directory of Open Access Journals (Sweden)

    Fogliazza Giuseppe

    2008-01-01

    Full Text Available Abstract In order to realize autonomous manufacturing systems in environments characterized by high dynamics and high complexity of task, it is necessary to improve the control system modelling and performance. This requires the use of better and reusable abstractions. In this paper, we explore the metamodel techniques as a foundation to the solution of this problem. The increasing popularity of model-driven approaches and a new generation of tools to support metamodel techniques are changing software engineering landscape, boosting the adoption of new methodologies for control application development.

  13. Metamodeling Techniques Applied to the Design of Reconfigurable Control Applications

    Directory of Open Access Journals (Sweden)

    Luca Ferrarini

    2008-02-01

    Full Text Available In order to realize autonomous manufacturing systems in environments characterized by high dynamics and high complexity of task, it is necessary to improve the control system modelling and performance. This requires the use of better and reusable abstractions. In this paper, we explore the metamodel techniques as a foundation to the solution of this problem. The increasing popularity of model-driven approaches and a new generation of tools to support metamodel techniques are changing software engineering landscape, boosting the adoption of new methodologies for control application development.

  14. A time-delay suppression technique for DPWM control circuit

    OpenAIRE

    Ishizuka, Yoichi; Hirose, Fumitoshi; Yamada, Yusuke; Matsuo, Hirofumi

    2009-01-01

    A proposed design of a low-cost digital pulse width modulation (DPWM) control circuit for non-isolated DC-DC converter without A/D converter is described. Also, propsed real-time PID control technique for DPWM is described. Some experimental results and simulation results are revealed the proposed circuit and scheme. The purpose of this research is striking a balance between minimizing cost increase by digitalizing of the control circuit of DC-DC converter and speeding up the control circuit.

  15. 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

  16. A Digital Controller for Active Aeroelastic Controls

    OpenAIRE

    Ueda, Tetsuhiko; MUROTA, Katsuichi; 上田, 哲彦; 室田, 勝一

    1989-01-01

    A high-speed digital controller for aeroelastic controls was designed and made. The purpose was to minimize adverse phase lag which is inevitably produced by the CPU time of digital processing. The delay deteriorates control performances on rather rapid phenomena like aircraft flutter. With fix-point operation the controller realized 417 microseconds of throughput time including the A/D and D/A conversion. This corresponds to a high sampling rate of 2.4kHz. The controller furnishes two channe...

  17. SINGLE - PHASE INVERTER CONTROL TECHNIQUES FOR INTERFACING RENEWABLE ENERGY SOURCES

    OpenAIRE

    C.Nallasivam

    2015-01-01

    A novel current control technique is proposed to control power flow from a renewable energy source feeding a microgrid system through a three - phase parallel - connected inverter. The parallel - connected inverter ensures that the power flow from the grid with low - current total harmonic distortion even in the presence of nonlinear load. The renewable energy sources ar e paralleled, and the average of this constant sup...

  18. Abstraction and control techniques for non-stationary scheduling problems

    CERN Document Server

    Innocenti, Giacomo

    2009-01-01

    The paper faces the problem of scheduling from a new perspective, trying to bridge the gap between classical heuristic approaches and system identification and control strategies. To this aim, a complete mathematical formulation of a general scheduling process is derived, beginning from very broad assumptions. This allows a greater freedom of manipulation and guarantee the resolution of the identification (and control) techniques. Both an adaptive and a switching strategies are presented in relation to the performances of a simple Round Robin algorithm.

  19. Development of irradiation technique on controlling food contamination residue

    International Nuclear Information System (INIS)

    The current state of the researches of irradiation technology on controlling food mycotoxin, pesticide, veterinary drugs and fishery drugs residue was summarized. And the degradation rate, mechanism, products and toxicities of food contamination were expatiated. The free radical from irradiation attack the site of weaker bond, and the less or more toxic substances were produced, which lead to the degradation of the food contamination. The limitations and future application of irradiation technique on controlling food contamination were also analyzed. (authors)

  20. Sterile insect technique and radiation in insect control

    International Nuclear Information System (INIS)

    Out of 39 papers and 6 summaries of the poster presentations published in this proceeding series, 23 respectively fall within the INIS subject scope. Four main topics were covered: a review of the sterile insect technique against various insect pests; its application to tsetse flies in eradication programmes; quality control of mass-reared insects for release; and the development of genetic approaches to insect mass rearing and control. Other topics emphasized integrated pest management, computer models and radioisotope labelling

  1. Tsetse control, diagnosis and chemotherapy using nuclear techniques

    International Nuclear Information System (INIS)

    The focus of the seminar was on recent advances in the use of nuclear techniques in the diagnosis and control of tsetse-transmitted trypanosomiasis. The proceedings contain the full text of sixteen selected papers addressing the disease and its diagnosis, chemotherapy, vector biology, ecology and control. Synopses of the other papers presented are also included. The individual contributions are indexed separately. Refs, figs and tabs

  2. DIRECT TORQUE CONTROL FOR INDUCTION MOTOR USING INTELLIGENT TECHNIQUES

    Directory of Open Access Journals (Sweden)

    R.Toufouti

    2007-09-01

    Full Text Available In this paper, we propose two approach intelligent techniques of improvement of Direct Torque Control (DTC of Induction motor such as fuzzy logic (FL and artificial neural network (ANN, applied in switching select voltage vector .The comparison with conventional direct torque control (DTC, show that the use of the DTC_FL and DTC_ANN, reduced the torque, stator flux, and current ripples. The validity of the proposed methods is confirmed by the simulative results.

  3. Power electronic converters PWM strategies and current control techniques

    CERN Document Server

    Monmasson, Eric

    2013-01-01

    A voltage converter changes the voltage of an electrical power source and is usually combined with other components to create a power supply. This title is devoted to the control of static converters, which deals with pulse-width modulation (PWM) techniques, and also discusses methods for current control. Various application cases are treated. The book is ideal for professionals in power engineering, power electronics, and electric drives industries, as well as practicing engineers, university professors, postdoctoral fellows, and graduate students.

  4. COMPARISON OF ACTIVE RELEASE TECHNIQUE AND MYOFASCIAL RELEASE TECHNIQUE ON PAIN, GRIP STRENGTH & FUNCTIONAL PERFORMANCE IN PATIENTS WITH CHRONIC LATERAL EPICONDYLITIS

    Directory of Open Access Journals (Sweden)

    Parth Trivedi

    2014-06-01

    Full Text Available Background & Purpose: Lateral epicondylitis is the most common lesion of the elbow. Tennis elbow or lateral epicondylitis is defined as a syndrome of pain in the wrist extensor muscles at or near their lateral epicondyle origin or pain directly over the lateral epicondyle. So, the aim of this study was to compare the effectiveness of Active Release Technique (ART and Myofascial Release Technique (MFR in the treatment of Chronic Lateral Epicondylitis (CLE. Methodology: The study included thirty-six patients with Chronic Lateral Epicondylitis of age group range between 30 to 45 years. Patients were randomly divided into three groups: Control Group (A, Active Release Technique Group (B and Myofascial Release Technique Group (C. The patients were treated for 4 weeks and three outcome measures: 0-10 NPRS, Hand Dynamometer and PRTEE were taken for assessment and analysis at baseline and after 4th weeks was done. Result: In this study the result showed that Active Release Technique and Myofascial Release Technique were effective in all three outcome measures when compared to Control Group. Myofascial Release Technique was more effective in improving grip strength & reducing pain & disability when compared to Active Release Technique.(p<0.05 Conclusion: Active Release Technique and Myofascial Release Technique are effective in patients with Chronic Lateral Epicondylitis. Myofascial Release Technique demonstrated better outcomes than Active Release Technique in the management of Chronic Lateral Epicondylitis.

  5. Control Techniques in Heating, Ventilating and Air Conditioning Systems

    Directory of Open Access Journals (Sweden)

    H. Mirinejad

    2008-01-01

    Full Text Available Problem statement: Heating, Ventilating and Air Conditioning (HVAC systems are among the main installations in residential, commercial and industrial buildings. The purpose of the HVAC systems is normally to provide a comfortable environment in terms of temperature, humidity and other environmental parameters for the occupants as well as to save energy. Achieving these objectives requires a suitable control system design. Approach: In this overview, thermal comfort level and ISO comfort field is introduced, followed by a review and comparison of the main existing control techniques used in HVAC systems to date. Results: The present overview shows that intelligent controllers which are based on the human sensation of thermal comfort have a better performance in providing thermal comfort as well as energy saving than the traditional controllers and those based on a model of the HVAC system. Conclusion: Such an overview provides an insight into current control methods in HVAC systems and can help scholars and HVAC learners to have the comprehensive information about a variety of control techniques in the field of HVAC and therefore to better design a proper controller for their work

  6. Active control of aerodynamic noise; Active control ni yoru furyoku soon no seigyo

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, M. [Mitsubishi Heavy Industries, Ltd., Tokyo (Japan)

    1996-10-01

    This paper introduces summary and examples of active noise control (ANC) and active flow control (AFC) as the aerodynamic noise control techniques. The ANC is a technique to generate noise of a reverse phase which cancels the original noise. Noise reduced especially effectively by the ANC is noise from fans and ducts used for engine air supply and exhaust. The ANC is effective in low frequencies, and when used with a passive method, a compact exhaust silencer can be realized, which has high noise reducing performance over the whole frequency band and has low pressure loss. Signal processing in active noise reduction system is always so adjusted that noise is discharged from a secondary noise source in which signals detected by a detection microphone is given a digital filter treatment, and output from an error microphone is minimized. The AFC has been incapable of realizing a reverse phase over a wide frequency band when depended on analog treatment. However, the authors have developed an adaptive type feedback control system, and verified that the system can be applied to any frequency variation and control it in a stable manner. 15 refs., 9 figs., 1 tab.

  7. Reinforcement learning output feedback NN control using deterministic learning technique.

    Science.gov (United States)

    Xu, Bin; Yang, Chenguang; Shi, Zhongke

    2014-03-01

    In this brief, a novel adaptive-critic-based neural network (NN) controller is investigated for nonlinear pure-feedback systems. The controller design is based on the transformed predictor form, and the actor-critic NN control architecture includes two NNs, whereas the critic NN is used to approximate the strategic utility function, and the action NN is employed to minimize both the strategic utility function and the tracking error. A deterministic learning technique has been employed to guarantee that the partial persistent excitation condition of internal states is satisfied during tracking control to a periodic reference orbit. The uniformly ultimate boundedness of closed-loop signals is shown via Lyapunov stability analysis. Simulation results are presented to demonstrate the effectiveness of the proposed control. PMID:24807456

  8. H(sub infinity) techniques for spacecraft control

    Science.gov (United States)

    Frapard, B.; Leballois, S.; Champetier, C.

    1993-09-01

    The high performance Attitude and Orbit Control Systems (AOCS) and high accuracy Instrument Pointing Systems design require more and more control bandwidth: dynamic couplings can be no more neglected and control laws tend to be highly sensitive to the unmodeled dynamics. Multivariable systems analysis and optimal control synthesis tools, with robustness bounds/robustness constraints with respect to the unmodeled dynamics, are a major area of research for space applications. Among others, the large field of techniques provided by H(sub infinity) theory appears to be very promising. Two typical applications are presented in this paper, one concerning high accuracy pointing for observation satellites, with a particular interest in the SPOT Mark II platform, the other addressing the Drag Free Control problem for missions such as Aristoteles, STEP and Gravity Probe B.

  9. Insect population control by the sterile-male technique

    International Nuclear Information System (INIS)

    The successful use of the sterile male technique to eradicate the screw worm fly from the Southeastern part of the United States showed that a new biological method using radiation-sterilized insects could not only control but also eradicate harmful insect pests. A panel of experts met at the IAEA in Vienna in October 1962 to discuss the various aspects and applications of this new technique and to assess its usefulness and limitations. This report summarizes the panel proceedings. 42 refs, 18 figs, 1 tab

  10. 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.

  11. New approaches in intelligent control techniques, methodologies and applications

    CERN Document Server

    Kountchev, Roumen

    2016-01-01

    This volume introduces new approaches in intelligent control area from both the viewpoints of theory and application. It consists of eleven contributions by prominent authors from all over the world and an introductory chapter. This volume is strongly connected to another volume entitled "New Approaches in Intelligent Image Analysis" (Eds. Roumen Kountchev and Kazumi Nakamatsu). The chapters of this volume are self-contained and include summary, conclusion and future works. Some of the chapters introduce specific case studies of various intelligent control systems and others focus on intelligent theory based control techniques with applications. A remarkable specificity of this volume is that three chapters are dealing with intelligent control based on paraconsistent logics.

  12. UML activity diagram swimlanes in logic controller design

    Science.gov (United States)

    Grobelny, Michał; Grobelna, Iwona

    2015-12-01

    Logic controller behavior can be specified using various techniques, including UML activity diagrams and control Petri nets. Each technique has its advantages and disadvantages. Application of both specification types in one project allows to take benefits from both of them. Additional elements of UML models make it possible to divide a specification into some parts, considered from other point of view (logic controller, user or system). The paper introduces an idea to use UML activity diagrams with swimlanes to increase the understandability of design models.

  13. Non-Destructive Testing Techniques for Research and Process Control

    International Nuclear Information System (INIS)

    Non-destructive test methods have been used primarily for the detection of defects and the rejection of faulty materials. The Oak Ridge National Laboratory has found it valuable to employ special non-destructive testing techniques as aids in materials research, component development, and process control. This paper gives three recent examples of the evolution of non-destructive testing techniques from research to process control. A current fuel-element design contains fuel pins filled with vibratorily compacted uranium and thorium oxide powder. A gamma-attenuation technique was developed to allow the homogeneity of fuel loading to be measured and was used to aid the development of fabrication techniques and equipment. Later an inspection device was built to operate remotely in a hermetically sealed and shielded facility and used for production process control. Another fuel element required fuel plates containing a uranium oxide-aluminium dispersion core with a programmed variation in the fuel loading across the width. A continuous scanning, X-ray attenuation technique was developed and used to measure fuel inhomogeneities and conformity to design contour. The technique assisted the development for both core pressing and plate-rolling practices. A system was constructed for rapid automatic evaluation of production fuel plates. These fuel plates were pressed into involute shape and assembled with alternate cooling channels. Stringent heat-transfer requirements imposed a tight tolerance on the channel dimensions. A unique eddy-current device using the ''lift-off'' characteristic was invented to insert in the very narrow channel and allow recording of dimensions both during fabrication development and actual manufacture. Another approach to fuel elements is the use of minute fuel-bearing particles coated with pyrolytic carbon to retain the fission products. Of concern are the core diameter, coating thickness and integrity, and presence of fuel in the coating

  14. Finite element models applied in active structural acoustic control

    NARCIS (Netherlands)

    Oude Nijhuis, Marco H.H.; Boer, de André; Rao, Vittal S.

    2002-01-01

    This paper discusses the modeling of systems for active structural acoustic control. The finite element method is applied to model structures including the dynamics of piezoelectric sensors and actuators. A model reduction technique is presented to make the finite element model suitable for controll

  15. Multi-level overlay techniques for improving DPL overlay control

    Science.gov (United States)

    Chen, Charlie; Pai, Y. C.; Yu, Dennis; Pang, Peter; Yu, Chun Chi; Wu, Robert (Hsing-Chien); Huang, Eros (Chien Jen); Chen, Marson (Chiun-Chieh); Tien, David; Choi, Dongsub

    2012-03-01

    Overlay continues to be one of the key challenges for lithography in semiconductor manufacturing, especially in light of the accelerated pace of device node shrinks. This reality will be especially evident at 20nm node where DPL and multi-layer overlay will require 4nm or less in overlay control across many critical layers in order to meet device yield entitlements. The motivation for this paper is based on improving DPL overlay control in face of the high complexity involved with multi-layer overlay requirements. For example, the DPL-2nd-litho layer will need to achieve tight registration with the DPL-1st-litho layer, and at the same time, it will need to achieve tight overlay to the reference-litho layer, which in some cases can also be a DPL layer. Of course, multi-level overlay measurements are not new, but the combination of increased complexity of multi-DPL layers and extremely challenging overlay specifications for 20nm node together will necessitate a better understanding of multi-level overlay control, specifically in terms of root cause analysis of multi-layer related overlay errors and appropriate techniques for improvement In this paper, we start with the identification of specific overlay errors caused by multi-layer DPL processing on full film stack product wafers. After validation of these findings with inter-lot and intra-lot controlled experiments, we investigate different advanced control techniques to determine how to optimize overlay control and minimize both intra-lot and inter-lot sources of error. A new approach to overlay data analysis will also be introduced that combines empirical data with target image quality data to more accurately determine and better explain the root cause error mechanism as well as provide effective strategies for improved overlay control.

  16. An active control synchronization for two modified Chua circuits

    Science.gov (United States)

    Li, Guo-Hui

    2005-03-01

    From modern control theory, an active control method to synchronize two modified Chua circuits with each other, which exhibit chaos, is presented. Some sufficient conditions of linear stability of the chaotic synchronization are obtained from rigorous mathematic justification. On the basis of the state-observer, the controller is analytically deduced using the active control. It is shown that this technique can be applied to achieve synchronization of the two systems with each other, whether they are identical or not. Finally, numerical simulations show the effectiveness of the proposed control scheme.

  17. An active control synchronization for two modified Chua circuits

    Institute of Scientific and Technical Information of China (English)

    Li Guo-Hui

    2005-01-01

    From modern control theory, an active control method to synchronize two modified Chua circuits with each other, which exhibit chaos, is presented. Some sufficient conditions of linear stability of the chaotic synchronization are obtained from rigorous mathematic justification. On the basis of the state-observer, the controller is analytically deduced using the active control. It is shown that this technique can be applied to achieve synchroniztion of the tow systems with each other, whether they are identical or not. Finally, numerical simulations show the effectiveness of the proposed control scheme.

  18. Weed Identification Using An Automated Active Shape Matching (AASM) Technique

    DEFF Research Database (Denmark)

    Swain, K C; Nørremark, Michael; Jørgensen, R N;

    2011-01-01

    on the concept of ‘active shape modelling’ to identify weed and crop plants based on their morphology. The automated active shape matching system (AASM) technique consisted of, i) a Pixelink camera ii) an LTI (Lehrstuhlfuer technische informatik) image processing library, iii) a laptop pc with the Linux OS. A 2......-identification process required 0.062 s for eight iterations with the Linux platform used....

  19. Integrated controlling technique of ecological environment in Shendong Mining Area

    Institute of Scientific and Technical Information of China (English)

    ZHANG Dong-sheng; LIU Yu-de; WANG An; WANG Yi

    2007-01-01

    To enclose the interactive relation between the underground mining with suitable protection for surface ecological environments and surface prevention of ecological environments adapting to mining disturbing was researched and developed core of this technique. There are three aspects of controlling ecological environments, to dispose and renew before exploitation, to protect surface ecological environments in the exploitative process and to repair and build up after exploitation. Based on the moving law of overburden strata in shallow seam, the surface subsidence law and the growth law of vegetation in subsidence mine area, the integrated controlling technique has been developed synthetically by methods of theoretic analysis, laboratory simulation, numerical calculation,commercial test etc.. It includes the key techniques of aquifer-protective mining, filtering and purging of mine water through goaf, preventing and extinguishing fire in shallow seam,no-rock roadway layout and waste disposal in underground, frame-building ecological functional sphere before exploitation, frame-building the ecological cycle using system after mining and so on.

  20. A New Mathematical Modeling Technique for Pull Production Control Systems

    Directory of Open Access Journals (Sweden)

    O. Srikanth

    2013-12-01

    Full Text Available The Kanban Control System widely used to control the release of parts of multistage manufacturing system operating under a pull production control system. Most of the work on Kanban Control System deals with multi-product manufacturing system. In this paper, we are proposing a regression modeling technique in a multistage manufacturing system is to be coordinates the release of parts into each stage of the system with the arrival of customer demands for final products. And also comparing two variants stages of the Kanban Control System model and combines with mathematical and Simulink model for the production coordination of parts in an assembly manufacturing systems. In both variants, the production of a new subassembly is authorized only when an assembly Kanban is available. Assembly kanbans become available when finished product is consumed. A simulation environment for the product line system has to generate with the proposed model and the mathematical model have to give implementation against the simulation model in the working platform of MATLAB. Both the simulation and model outputs have provided an in depth analysis of each of the resulting control system for offering model of a product line system.

  1. Reinforcement learning techniques for controlling resources in power networks

    Science.gov (United States)

    Kowli, Anupama Sunil

    As power grids transition towards increased reliance on renewable generation, energy storage and demand response resources, an effective control architecture is required to harness the full functionalities of these resources. There is a critical need for control techniques that recognize the unique characteristics of the different resources and exploit the flexibility afforded by them to provide ancillary services to the grid. The work presented in this dissertation addresses these needs. Specifically, new algorithms are proposed, which allow control synthesis in settings wherein the precise distribution of the uncertainty and its temporal statistics are not known. These algorithms are based on recent developments in Markov decision theory, approximate dynamic programming and reinforcement learning. They impose minimal assumptions on the system model and allow the control to be "learned" based on the actual dynamics of the system. Furthermore, they can accommodate complex constraints such as capacity and ramping limits on generation resources, state-of-charge constraints on storage resources, comfort-related limitations on demand response resources and power flow limits on transmission lines. Numerical studies demonstrating applications of these algorithms to practical control problems in power systems are discussed. Results demonstrate how the proposed control algorithms can be used to improve the performance and reduce the computational complexity of the economic dispatch mechanism in a power network. We argue that the proposed algorithms are eminently suitable to develop operational decision-making tools for large power grids with many resources and many sources of uncertainty.

  2. Bonding techniques for hybrid active pixel sensors (HAPS)

    Energy Technology Data Exchange (ETDEWEB)

    Bigas, M. [Centre Nacional de Microelectronica, CNM-IMB (CSIC), Campus Universitat Autonoma de Barcelona, 08193 Bellaterra, Barcelona (Spain)]. E-mail: Marc.Bigas@cnm.es; Cabruja, E. [Centre Nacional de Microelectronica, CNM-IMB (CSIC), Campus Universitat Autonoma de Barcelona, 08193 Bellaterra, Barcelona (Spain)]. E-mail: Enric.Cabruja@cnm.es; Lozano, M. [Centre Nacional de Microelectronica, CNM-IMB (CSIC), Campus Universitat Autonoma de Barcelona, 08193 Bellaterra, Barcelona (Spain)

    2007-05-01

    A hybrid active pixel sensor (HAPS) consists of an array of sensing elements which is connected to an electronic read-out unit. The most used way to connect these two different devices is bump bonding. This interconnection technique is very suitable for these systems because it allows a very fine pitch and a high number of I/Os. However, there are other interconnection techniques available such as direct bonding. This paper, as a continuation of a review [M. Lozano, E. Cabruja, A. Collado, J. Santander, M. Ullan, Nucl. Instr. and Meth. A 473 (1-2) (2001) 95-101] published in 2001, presents an update of the different advanced bonding techniques available for manufacturing a hybrid active pixel detector.

  3. The Use of Management Control Systems and Operations Management Techniques

    Directory of Open Access Journals (Sweden)

    Edelcio Koitiro Nisiyama

    2016-01-01

    Full Text Available It is well known that both management control systems (MCSs and operations management (OM are related to firm performance; however, an integrated st udy that involves MCS and OM within the context of firm performance is still lacking. This research aimed to examine the relationships among the use of MCSs and OM techniques and firm performance in the Brazilian auto parts industry. Simons’ levers of cont rol framework was used to characterise the uses of MCSs, and OM techniques, such as total quality management (TQM and continuous improvement programmes, were adopted. The results obtained through the structural equation modelling indicated that the diagno stic use of MCSs is positively associated with the goals of cost reduction. In addition, the interactive use of MCSs is positively associated with the objectives of introducing new products, which is consistent with previous research. Additionally, OM tech niques are positively related to cost reduction but have no direct relationship with the introduction of new products.

  4. Volcanic Monitoring Techniques Applied to Controlled Fragmentation Experiments

    Science.gov (United States)

    Kueppers, U.; Alatorre-Ibarguengoitia, M. A.; Hort, M. K.; Kremers, S.; Meier, K.; Scharff, L.; Scheu, B.; Taddeucci, J.; Dingwell, D. B.

    2010-12-01

    Volcanic eruptions are an inevitable natural threat. The range of eruptive styles is large and short term fluctuations of explosivity or vent position pose a large risk that is not necessarily confined to the immediate vicinity of a volcano. Explosive eruptions rather may also affect aviation, infrastructure and climate, regionally as well as globally. Multiparameter monitoring networks are deployed on many active volcanoes to record signs of magmatic processes and help elucidate the secrets of volcanic phenomena. However, our mechanistic understanding of many processes hiding in recorded signals is still poor. As a direct consequence, a solid interpretation of the state of a volcano is still a challenge. In an attempt to bridge this gap, we combined volcanic monitoring and experimental volcanology. We performed 15 well-monitored, field-based, experiments and fragmented natural rock samples from Colima volcano (Mexico) by rapid decompression. We used cylindrical samples of 60 mm height and 25 mm and 60 mm diameter, respectively, and 25 and 35 vol.% open porosity. The applied pressure range was from 4 to 18 MPa. Using different experimental set-ups, the pressurised volume above the samples ranged from 60 - 170 cm3. The experiments were performed at ambient conditions and at controlled sample porosity and size, confinement geometry, and applied pressure. The experiments have been thoroughly monitored with 1) Doppler Radar (DR), 2) high-speed and high-definition cameras, 3) acoustic and infrasound sensors, 4) pressure transducers, and 5) electrically conducting wires. Our aim was to check for common results achieved by the different approaches and, if so, calibrate state-of-the-art monitoring tools. We present how the velocity of the ejected pyroclasts was measured by and evaluated for the different approaches and how it was affected by the experimental conditions and sample characteristics. We show that all deployed instruments successfully measured the pyroclast

  5. Quality assurance and quality control of nuclear analytical techniques

    International Nuclear Information System (INIS)

    Test and analytical laboratories in East and Central European countries need to prove the reliability and credibility of their economic, environmental, medical and legal decisions and their capacity of issuing reliable, verifiable reports. These demands imposed by the European Union aimed at avoiding a possible barrier to trade for the developing countries. In June 1999, in order to help Member States to develop according to EU objectives and the overall situation of the European market, IAEA launched a new co-operation programme designed to help the nuclear analytical laboratories in nuclear institutions and universities of Member States by training in the use of some Nuclear Analytical Techniques (NAT) that include: alpha, beta and gamma-ray spectrometry, radiochemical and neutron activation analysis, total reflection X-ray fluorescence. The Regional IAEA Project, named 'Quality Assurance/Quality Control of Nuclear Analytical Techniques' (NAT) aims at implementing the QA principles via a system of defined consecutive steps leading to a level on which the QA system is self-sustainable for formal accreditation or certification and satisfies the EU technical performance criteria; the requirements are in accordance with the new ISO/IEC 17025 Standard/Dec.1999 'General requirements for the competence of testing and calibration laboratories' - First edition. The Horia Hulubei National Institute for Nuclear Physics and Engineering, IFIN-HH, was admitted for participation in the IAEA Project in June 1999 account taken of its experience in the QA and metrology fields and its performance in the fields of beta and gamma-ray spectrometry, and radiochemical and neutron activation analysis, employed in both basic research and applications for external clients. Two working groups of specialists with the QA and Standardization and Metrology Departments and six analytical groups with the departments of Nuclear Applied Physics, Life Physics and Ionising Radiation Metrology are

  6. Nuclear and related techniques in the control of communicable diseases

    International Nuclear Information System (INIS)

    The IAEA has a programme component entitled ''Nuclear Techniques in Communicable Diseases'', the aims of which are to encourage research in the development of new methods of controlling communicable diseases and to transfer the technology to institutes in endemic regions. Implementation of the programme component includes information exchange through publications, symposiums and seminars. The two most recent seminars were held in Bombay in November 1988 and Belo Horizonte in November 1989, and a selection of the papers presented have been published in this Technical Document. Refs, figs and tabs

  7. Techniques for measuring vitamin A activity from β-carotene.

    Science.gov (United States)

    Tang, Guangwen

    2012-11-01

    Dietary β-carotene is the most important precursor of vitamin A. However, the determination of the efficiency of in vivo conversion of β-carotene to vitamin A requires sensitive and safe techniques. It presents the following challenges: 1) circulating β-carotene concentration cannot be altered by eating a meal containing ≤6 mg β-carotene; 2) because retinol concentrations are homeostatically controlled, the conversion of β-carotene into vitamin A cannot be estimated accurately in well-nourished humans by assessing changes in serum retinol after supplementation with β-carotene. In the past half-century, techniques using radioisotopes of β-carotene and vitamin A, depletion-repletion with vitamin A and β-carotene supplements, measurement of postprandial chylomicron fractions after consumption of a β-carotene dose, and finally, stable isotopes as tracers to follow the absorption and conversion of β-carotene in humans have been developed. The reported values for β-carotene to vitamin A conversion showed a wide variation from 2 μg β-carotene to 1 μg retinol (for synthetic pure β-carotene in oil) and 28 μg β-carotene to 1 μg retinol (for β-carotene from vegetables). In recent years, a stable isotope reference method (IRM) was developed that used labeled synthetic β-carotene. The IRM method provided evidence that the conversion of β-carotene to vitamin A is likely dose dependent. With the development of intrinsically labeled plant foods harvested from a hydroponic system with heavy water, vitamin A activity of stable isotope-labeled biosynthetic β-carotene from various foods consumed by humans was studied. The efficacy of plant foods rich in β-carotene, such as natural (spinach, carrots, spirulina), hybrid (high-β-carotene yellow maize), and bioengineered (Golden Rice) foods, to provide vitamin A has shown promising results. The results from these studies will be of practical importance in recommendations for the use of pure β-carotene and foods

  8. Practical applications of activation analysis and other nuclear techniques

    International Nuclear Information System (INIS)

    Neeutron activation analysis (NAA) is a versatile, sensitive multielement, usually nondestructive analytical technique used to determine elemental concentrations in a variety of materials. Samples are irradiated with neutrons in a nuclear reactor, removed, and for the nondestructive technique, the induced radioactivity measured. This measurement of γ rays emitted from specific radionuclides makes possible the quantitative determination of elements present. The method is described, advantages and disadvantages listed and a number of examples of its use given. Two other nuclear methods, particle induced x-ray emission and synchrotron produced x-ray fluorescence are also briefly discussed

  9. Control techniques for an automated mixed traffic vehicle

    Science.gov (United States)

    Meisenholder, G. W.; Johnston, A. R.

    1977-01-01

    The paper describes an automated mixed traffic vehicle (AMTV), a driverless low-speed tram designed to operate in mixed pedestrian and vehicular traffic. The vehicle is a six-passenger electric tram equipped with sensing and control which permit it to function on existing streets in an automatic mode. The design includes established wire-following techniques for steering and near-IR headway sensors. A 7-mph cruise speed is reduced to 2 mph or a complete stop in response to sensor (or passenger) inputs. The AMTV performance is evaluated by operation on a loop route and by simulation. Some necessary improvements involving sensors, sensor pattern, use of an audible signal, and control lag are discussed. It is suggested that appropriate modifications will eliminate collision incidents.

  10. Cooperative Control Method of Active and Semiactive Control: New Framework for Vibration Control

    OpenAIRE

    Kazuhiko Hiramoto

    2014-01-01

    A new control design framework for vibration control, the cooperative control of active and semiactive control, is proposed in the paper. In the cooperative control, a structural system having both of an actuator and a semiactive control device, for example, MR damper and so forth, is defined as the control object. In the proposed control approach, the higher control performance is aimed by the cooperative control between the active control with the actuator and the semiactive control with th...

  11. Development of Active Noise Control System for Quieting Transformer Noise

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Bok Kyu; Song, Seik Young; Choi, Huo Yul [Korea Electric Power Research Institute, Taejon (Korea, Republic of); Yun, Dae Hea; Lee, Hyuk Jae [Korea Electrotechnology Research Institute, Changwon (Korea, Republic of)

    1997-12-31

    The passive noise control technique made use of sound-absorbing or soundproofing materials, so it required a large area and high cost for installation and had a drawback of poor performance at low frequency. Compared to this, the Active Noise Control attenuates noise sound pressure by using secondary source which has same performance ay low-frequency. Furthermore, it is able to save space and expenses. - research on adaptive algorithms - evaluation of global attenuation of the control - computer simulation - real-time Active Noise Control System Hardware Implementation - ANC system setting in the noisy area.

  12. Evolutionary biology and genetic techniques for insect control.

    Science.gov (United States)

    Leftwich, Philip T; Bolton, Michael; Chapman, Tracey

    2016-01-01

    The requirement to develop new techniques for insect control that minimize negative environmental impacts has never been more pressing. Here we discuss population suppression and population replacement technologies. These include sterile insect technique, genetic elimination methods such as the release of insects carrying a dominant lethal (RIDL), and gene driving mechanisms offered by intracellular bacteria and homing endonucleases. We also review the potential of newer or underutilized methods such as reproductive interference, CRISPR technology, RNA interference (RNAi), and genetic underdominance. We focus on understanding principles and potential effectiveness from the perspective of evolutionary biology. This offers useful insights into mechanisms through which potential problems may be minimized, in much the same way that an understanding of how resistance evolves is key to slowing the spread of antibiotic and insecticide resistance. We conclude that there is much to gain from applying principles from the study of resistance in these other scenarios - specifically, the adoption of combinatorial approaches to minimize the spread of resistance evolution. We conclude by discussing the focused use of GM for insect pest control in the context of modern conservation planning under land-sparing scenarios. PMID:27087849

  13. 基于自抗扰技术的火箭炮伺服系统解耦控制%Decoupling Control of Rocket Launcher Servo System Based on Active Disturbance Rej ection Technique

    Institute of Scientific and Technical Information of China (English)

    郑颖; 马大为; 姚建勇; 乐贵高

    2014-01-01

    Rocket launcher servo system is a kind of servo system with azimuth axis and pitch axis coupling.For the sake of researching two-axis coupling and strong disturbance of combus-tion gas flow impact,the two-axis coupling dynamics equations and differential equations of rocket launcher were established.The extended state observer and virtual control variable were designed based on active disturbance rej ection control for decoupling.The total disturbance was estimated through extended state observer and system compensation.The real control law was obtained from virtual control variable to control the coupling system.The simulation results indicated that the proposed control method can improve the tracking precision of rocket laun-cher and restrain the vibration of launching platform with two-axis coupling effect and combus-tion gas flow impact,and the control method can also provide theoretical support and actual value for rocket launcher coupling servo system.%火箭炮伺服系统为方位和俯仰两轴耦合的伺服系统。为研究发射时的两轴耦合问题及燃气流冲击强干扰影响,建立了火箭炮伺服系统双轴转台动力矩方程和耦合系统微分方程,采用基于自抗扰技术的解耦控制方法设计了扩张状态观测器及虚拟控制量。通过扩张状态观测器估计系统总扰动并进行实时补偿,通过虚拟控制量得到实际控制量对耦合系统进行控制。仿真结果表明,基于自抗扰技术的解耦控制提高了火箭炮伺服系统跟踪精度,使系统在两轴负载转矩耦合效应和燃气流冲击下有效地抑制了发射平台振动,满足控制性能指标,对火箭炮两轴耦合控制问题具有一定的理论意义和实用价值。

  14. A control technique for integration of DG units to the electrical networks

    DEFF Research Database (Denmark)

    Pouresmaeil, Edris; Miguel-Espinar, Carlos; Massot-Campos, Miquel;

    2013-01-01

    This paper deals with a multiobjective control technique for integration of distributed generation (DG) resources to the electrical power network. The proposed strategy provides compensation for active, reactive, and harmonic load current components during connection of DG link to the grid...... and utility grid. By setting an appropriate compensation current references from the sensed load currents in control circuit loop of DG, the active, reactive, and harmonic load current components will be compensated with fast dynamic response, thereby achieving sinusoidal grid currents in phase with load...... voltages, while required power of the load is more than the maximum injected power of the DG to the grid. In addition, the proposed control method of this paper does not need a phase-locked loop in control circuit and has fast dynamic response in providing active and reactive power components of the grid...

  15. Power Control Technique for Efficient Call Admission Control in Advanced Wirless Networks

    Directory of Open Access Journals (Sweden)

    Ch. Sreenivasa Rao

    2012-06-01

    Full Text Available In 4G networks, call admission control techniques have been proposed to provide Quality of Service (QoS in a network by restricting the access to network resources. Power control is essential in call admission control in order to provide fair access to all users, improve battery lifetime and system performance. But the existing call admission control algorithms rarely consider the power controlling techniques in the handoff process for different traffic classes. In this paper, we propose to develop a power controlled call admission control scheme for handoff in the advanced wireless networks. The incoming call measures the initial interference on it and then the base station starts transmitting the packets to the new call. The new call is rejected when the interference reaches a threshold value.Whenever an existing call meets the power constraint, the transmit power is decremented based on thetraffic class and incoming call obtains this information by monitoring the interference received on it. Theconvergence of the power control algorithm is checked and the power levels of all incoming calls areadjusted. From our simulation results we prove that this power control technique provides efficienthandoff in the 4G networks by increasing the throughput and reducing the delay of the existing users.

  16. Microglial control of neuronal activity

    Directory of Open Access Journals (Sweden)

    Catherine eBéchade

    2013-03-01

    Full Text Available Fine-tuning of neuronal activity was thought to be a neuron-autonomous mechanism until the discovery that astrocytes are active players of synaptic transmission. The involvement of astrocytes has changed our understanding of the roles of non-neuronal cells and shed new light on the regulation of neuronal activity. Microglial cells are the macrophages of the brain and they have been mostly investigated as immune cells. However recent data discussed in this review support the notion that, similarly to astrocytes, microglia are involved in the regulation of neuronal activity. For instance, in most, if not all, brain pathologies a strong temporal correlation has long been known to exist between the pathological activation of microglia and dysfunction of neuronal activity. Recent studies have convincingly shown that alteration of microglial function is responsible for pathological neuronal activity. This causal relationship has also been demonstrated in mice bearing loss-of-function mutations in genes specifically expressed by microglia. In addition to these long-term regulations of neuronal activity, recent data show that microglia can also rapidly regulate neuronal activity, thereby acting as partners of neurotransmission.

  17. Two-phase flow measurement by pulsed neutron activation techniques

    International Nuclear Information System (INIS)

    The Pulsed Neutron Activation (PNA) technique for measuring the mass flow velocity and the average density of two-phase mixtures is described. PNA equipment can be easily installed at different loops, and PNA techniques are non-intrusive and independent of flow regimes. These features of the PNA technique make it suitable for in-situ measurement of two-phase flows, and for calibration of more conventional two-phase flow measurement devices. Analytic relations governing the various PNA methods are derived. The equipment and procedures used in the first air-water flow measurement by PNA techniques are discussed, and recommendations are made for improvement of future tests. In the present test, the mass flow velocity was determined with an accuracy of 2%, and average densities were measured down to 0.08 g/cm3 with an accuracy of 0.04 g/cm3. Both the accuracy of the mass flow velocity measurement and the lower limit of the density measurement are functions of the injected activity and of the total number of counts. By using a stronger neutron source and a larger number of detectors, the measurable density can be decreased by a factor of 12 to .007 g/cm3 for 12.5 cm pipes, and to even lower ranges for larger pipes

  18. Developing Internal Controls through Activities

    Science.gov (United States)

    Barnes, F. Herbert

    2009-01-01

    Life events can include the Tuesday afternoon cooking class with the group worker or the Saturday afternoon football game, but in the sense that Fritz Redl thought of them, these activities are only threads in a fabric of living that includes all the elements of daily life: playing, working, school-based learning, learning through activities,…

  19. Techniques for Surveying Urban Active Faults by Seismic Methods

    Institute of Scientific and Technical Information of China (English)

    Xu Mingcai; Gao Jinghua; Liu Jianxun; Rong Lixin

    2005-01-01

    Using the seismic method to detect active faults directly below cities is an irreplaceable prospecting technique. The seismic method can precisely determine the fault position. Seismic method itself can hardly determine the geological age of fault. However, by considering in connection with the borehole data and the standard geological cross-section of the surveyed area, the geological age of reflected wave group can be qualitatively (or semi-quantitatively)determined from the seismic depth profile. To determine the upper terminal point of active faults directly below city, it is necessary to use the high-resolution seismic reflection technique.To effectively determine the geometric feature of deep faults, especially to determine the relation between deep and shallow fracture structures, the seismic reflection method is better than the seismic refraction method.

  20. Application of neutron activation tracer sediment technique on environmental science

    Institute of Scientific and Technical Information of China (English)

    YinYi; ZhongWei-Ni; 等

    1997-01-01

    Field and laboratory inverstigations were carried out to study the transport and dispersion law of polluted sediments near wastewater outlet using neutron activation tracer technique.The direction of transport and dispersion of polluted sediments,dispersion amount in different directions,sedimentary region of polluted sediment and evaluation of polluted risk are given.This provided a new test method for the study of environmental science and added a new forecasted content for the evaluation of environmental influence.

  1. Time-Based Dithering Algorithm and Frame Rate Control Technique for STN LCD Controller

    Institute of Scientific and Technical Information of China (English)

    LEIJianming; ZOUXuechen

    2004-01-01

    Time-based dithering algorithm and Frame rate control (FRC) technique applied to the STN liquid crystal display controller are presented. The dithering unit performs time-based dithering algorithm on pixel data to advantageously increase smoothness of an image displayed. The frame rate control unit is responsive to the dithering unit and performs frame rate controlling to generate more gray-shades, which may reduce flicker and visual artifacts. Results show that the gray shades displayed on images can be up to 256 for monochrome STN LCD panels or 2563 colors for color STN LCD panels respectively by using timebased dithering algorithm and frame rate control technique if each encoded pixel data is 8 bits. The images displayed on the STN liquid crystal display can get desirable grayshades and very little flicker and visual artifacts.

  2. Vibration control of active structures an introduction

    CERN Document Server

    Preumont, Andre

    2002-01-01

    This text is an introduction to the dynamics of active structures and to the feedback control of lightly damped flexible structures. The emphasis is placed on basic issues and simple control strategies that work.

  3. Active Noise Feedback Control Using a Neural Network

    Directory of Open Access Journals (Sweden)

    Zhang Qizhi

    2001-01-01

    Full Text Available The active noise control (ANC is discussed. Many digital ANC systems often based on the filter-x algorithm for finite impulse response (FIR filter use adaptive filtering techniques. But if the primary noise path is nonlinear, the control system based on adaptive filter technology will be invalid. In this paper, an adaptive active nonlinear noise feedback control approach using a neural network is derived. The feedback control system drives a secondary signal to destructively interfere with the original noise to cut down the noise power. An on-line learning algorithm based on the error gradient descent method was proposed, and the local stability of closed loop system is proved using the discrete Lyapunov function. A nonlinear simulation example shows that the adaptive active noise feedback control method based on a neural network is very effective to the nonlinear noise control.

  4. Application Of Nuclear Techniques In Environmental Studies And Pollution Control

    International Nuclear Information System (INIS)

    Environmental pollution has become a world wide concern. One of the main sources of such pollution is sewage wastewater and sludge. Their utilization without proper treatment can pollute the ecosystem (plant, soil, surface and ground water). Sewage wastewater and sludge contains several pollutants such as: pathogens, toxic organic compounds, heavy metals, high level of BOD and COD, seed weed. The reuse of sewage water and sludge in agriculture can lead to the transfer of some of these pollutants into the food chain causing health hazard. In addition, most of these contaminants are not biodegradable, becoming dangerous to plant and human health. Nuclear techniques has recently been used to control environmental pollution. Ionizing radiation provide a fast and reliable means of sewage water and sludge treatment than the conventional methods. Gamma radiation ( 60Co) and electron beam (accelerator) has been successfully used for alleviation of environmental pollution. Such alleviation includes: disinfection of harmful pathogens, degradation of toxic organic pollutants, destruction of seed weed and reduction of soluble heavy metals, odor and BOD and COD. The use of radioactive and stable isotopes are a useful tools to investigate the contribution of sludge nutrients to plant nutrition. Nitrogen, using 15N-ammonium sulfate, uptake and translocation by plant from soil amended with sewage sludge was studied under field condition. The contribution of sludge to phosphorus nutrition of plants was quantified using 32p as tracer. In both cases the principal of isotopic dilution technique was applied. The information generated from these experiments could help preserve the environment. It could help optimize the application rate of sludge to meet plant requirements while avoiding the accumulation of N and P in the soil or leaching to the aquifer. Isotope exchange kinetic technique is used to evaluate nutrients availability from sludge. Neutron moisture meter is used to measure

  5. Nondestructive techniques for the control of conditioned radioactive wastes

    International Nuclear Information System (INIS)

    The final product of the radwaste conditioning process must satisfy certain requirments and physico-chemical properties in order to assure its safe long-term behaviour. Of course, the foreseen quality assurance and quality control should be conducted by means of non-destructive techniques. This work presents an over-view of various applicable non-destructive methods of analysis, showing their fields of investigation in testing waste packages, together with some arising practical problems. The most promising methods, such as eddy current testing, ultrasonic testing, γ-scanning, γ-spectroscopy, neutron counting and computerized tomography, are treated more deeply and some applications are presented. Particular attention is devoted to the development of a device based on computerized tomography; its essential components are reported and some design problems are also discussed

  6. An Improved Production Activity Control Architecture for Shop Floor Control

    Institute of Scientific and Technical Information of China (English)

    SHAHIDIkramullahButt; SUNHou-fang; HAMIDUllahKhanNiazi

    2005-01-01

    This paper presents a further improved Production Activity Control Architecture to deal with the complexity of information by creating Sub-Producers and Sub-Movers which will not only give a better control at workstation level but also reduce load on the Dispatcher. It also makes an analysis of the basic and improved PAC (Production Activity Control) Architecture in the Control System for Integrated Manufacturing. The PAC Architecture and the improvement will further enhance the flexibility and adaptability of the architecture in the ever changing environment of the Shop Floor Control (SFC) Systems.

  7. Advanced terahertz techniques for quality control and counterfeit detection

    Science.gov (United States)

    Ahi, Kiarash; Anwar, Mehdi

    2016-04-01

    This paper reports our invented methods for detection of counterfeit electronic. These versatile techniques are also handy in quality control applications. Terahertz pulsed laser systems are capable of giving the material characteristics and thus make it possible to distinguish between the materials used in authentic components and their counterfeit clones. Components with material defects can also be distinguished in section in this manner. In this work different refractive indices and absorption coefficients were observed for counterfeit components compared to their authentic counterparts. Existence of unexpected ingredient materials was detected in counterfeit components by Fourier Transform analysis of the transmitted terahertz pulse. Thicknesses of different layers are obtainable by analyzing the reflected terahertz pulse. Existence of unexpected layers is also detectable in this manner. Recycled, sanded and blacktopped counterfeit electronic components were detected as a result of these analyses. Counterfeit ICs with die dislocations were detected by depicting the terahertz raster scanning data in a coordinate plane which gives terahertz images. In the same manner, raster scanning of the reflected pulse gives terahertz images of the surfaces of the components which were used to investigate contaminant materials and sanded points on the surfaces. The results of the later technique, reveals the recycled counterfeit components.

  8. Nuclear Activation Techniques in the Life Sciences. Proceedings of the Symposium on Nuclear Activation Techniques in the Life Sciences

    International Nuclear Information System (INIS)

    Proceedings of a Symposium organized by the IAEA and held at Amsterdam. 8-12 May 1967. The meeting was attended by 190 participants from 26 Member States and 3 international organizations. These are the third IAEA Symposium Proceedings to have nuclear activation analysis as their main theme, the preceding ones being Radioactivation Analysis, Butterworth and Co. Ltd, London (1960) and Radiochemical Methods of Analysis, IAEA, Vienna (1965). Contents: Introductory lecture (1 paper); Physical techniques (6 papers); Chemical techniques (6 papers); Analytical reference materials (1 paper); Comparison of activation analysis with other methods of trace analysis (4 papers); Plant and animal studies (7 papers); Medical sciences (19 papers); Public health and forensic science (6 papers). Each paper is in its original language (43 English, 5 French, 1 Russian and 1 Spanish) and is preceded by an abstract in English with one in the original language if this is not English. Discussions are in English. (author)

  9. Microscope-controlled glass bead blasting: a new technique

    Directory of Open Access Journals (Sweden)

    Peter Kotschy

    2011-01-01

    Full Text Available Peter Kotschy1, Sascha Virnik2, Doris Christ3, Alexander Gaggl21Private Practice, Vienna, Austria; 2Department of Oral and Maxillofacial Surgery, Central Hospital, Klagenfurt, Austria; 3Klagenfurt, AustriaObjective: The aim of periodontal therapy is the healing of periodontal inflammation; the protection of the attachment and the alveolar bone; and the regeneration of the periodontal structures. In the therapy of periodontitis, supra- and subgingival scaling and root planing plays a main role. The procedure described combines perfect root cleaning without scaling and root planing and minimal invasive periodontal surgery without a scalpel.Material and methods: Glass beads of 90 µm were used with the kinetic preparation unit PrepStart® under a pressure of 0.5–5 bar. This technique was practised only under visual control using the OPMI® PRO Magis microscope. Seven examinations were carried out at baseline after 3, 6, 12, 18, 24, and 36 months.Results: Time shows a statistically significant influence on all of the considered target variables (P < 0.0001 for all. As the according estimate is negative, probing depth decreases over time. The major decrease seems to be during the first 6 months. Considering probing depth, plaque on the main effect root shows significant influence (again, P < 0.0001 for all. Observations with high probing depth at the beginning were faster than those with low probing depth. The same characteristic appears by attachment level. Patients with more loss of attachment show more gain.Conclusions: Using microscope-controlled glass bead blasting results in a perfectly clean root surface using visual control (magnification 20×. Microscope-controlled glass bead blasting is therefore a good alternative to periodontal surgery.Keywords: periodontal therapy, microscope, periodontitis

  10. Feasibility of Applying Controllable Lubrication Techniques to Reciprocating Machines

    DEFF Research Database (Denmark)

    Pulido, Edgar Estupinan

    conventional lubrication conditions, a mathematical model of a reciprocating mechanism connected to a rigid / flexible rotor via thin fluid films was developed. The mathematical model involves the use of multibody dynamics theory for the modelling of the reciprocating mechanism (rigid bodies), finite elements...... modified hydrostatic lubrication. In this case, the hydrostatic lubrication is modified by injecting oil at controllable pressures, through orifices circumferentially located around the bearing surface. In order to study the performance of journal bearings of reciprocating machines, operating under...... method for the modelling of the flexible rotor (crankshaft) and hydrodynamic fluid film theory for describing the dynamics of the thin fluid films. When active lubrication is introduced to modify conventional hydrodynamic lubrication, by means of aplying radial oil injection at controllable oil pressures...

  11. Optical control of antibacterial activity

    NARCIS (Netherlands)

    Velema, Willem A.; van der Berg, Jan Pieter; Hansen, Mickel J.; Szymanski, Wiktor; Driessen, Arnold J. M.; Feringa, Ben L.

    2013-01-01

    Bacterial resistance is a major problem in the modern world, stemming in part from the build-up of antibiotics in the environment. Novel molecular approaches that enable an externally triggered increase in antibiotic activity with high spatiotemporal resolution and auto-inactivation are highly desir

  12. Automobile active suspension system with fuzzy control

    Institute of Scientific and Technical Information of China (English)

    刘少军; 黄中华; 陈毅章

    2004-01-01

    A quarter-automobile active suspension model was proposed. High speed on/off solenoid valves were used as control valves and fuzzy control was chosen as control method . Based on force analyses of system parts, a mathematical model of the active suspension system was established and simplified by linearization method. Simulation study was conducted with Matlab and three scale coefficients of fuzzy controller (ke, kec, ku) were acquired. And an experimental device was designed and produced. The results indicate that the active suspension system can achieve better vibration isolation performance than passive suspension system, the displacement amplitude of automobile body can be reduced to 55%. Fuzzy control is an effective control method for active suspension system.

  13. [Population dynamics and control techniques of aphids on honeysuckle].

    Science.gov (United States)

    Sun, Ying; Xue, Ming; Zhang, Xiao; Zhao, Hai-Peng; Li, Zhao-Xia

    2013-11-01

    The objective of this study is to define the population dynamics of Semiaphis heraclei in the main-producing district of Lonicera japonica in Shandong, and screen for highly efficient, safety control technique. Through fixed field investigation, we tested the toxicity of eight kinds of insecticides by using dipping methods, and carried out the field experiment. The results showed that the aphids' emergence peak appeared in May. The aphids on the Sijihua variety of L. japonica was more susceptible and the peak was also seven days earlier than Damao variety of L. japonica. The aphid populations on Sijihua were 1 fold than those on the Daomao in happened peak. Comparing the eight kinds of insecticides, the LC50 of lambda-cyhaothrin, abamectin, imidacloprid and pyrethrin to wingless aphids were 1.494, 1.690, 2.840, 2.861 mg x L(-1), respectively, whose toxicity were higher, the toxicity of matrine, pymetrozine and azadirachtin were also high. The field efficacy trials indicated that during the period of aphids occurred, 25% imidacloprid wettable powder, 1.8% abamectin missible oil, 2.5% lambda-cyhaothrin missible oil, 25% pymetrozine wettable powder, 5% pyrethrin missible oil, 1% matrine water aqua were sprayed at concentrations of 20,000, 2,000, 2,500, 5,000, 500 and 50 times, respectively,the control effect achieved 91.69%, 98.90%, 96.18%, 95.06%, 99.24%, 90.10%, respectively, after 5 days. During the growing period of L. japonica in spring, application of thiamethoxam, thiacloprid, pymetrozine and imidacloprid, all of the control effect against aphids achieved above 98.88% after 50 days. The result indicated that May was the S. heraclei Takahashi's emergence peak in Pingyi, Shandong. The efficient safety and environmentally friendly insecticides by spraying and systemic insecticide of pymetrozine and imidacloprid by root application were all efficient controlled aphids. These insecticides were long for controlling S. heraclei Takahashi and worthy of being widely

  14. SLIDING MODE CONTROL FOR ACTIVE AUTOMOBILE SUSPENSIONS

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Nonlinear control methods are presented based on theory of sliding mode control (SMC) or variable structure control (VSC) for application to active automobile suspensions. Requirements of reducing manufacturing cost and energy consumption of the active suspension system may be satisfiedby reasonable design of the sliding surface and hydraulic servo system. Emphasis is placed on the study of the discrete sliding mode control method (DSMC) applicable for a new sort of speed on-off solenoid valves of anti-dust capability and low price. Robustness and effectiveness of the feedback linearized controller in typical road conditions are demonstrated by numerical results fora quarter-car suspension model.

  15. Finite element models applied in active structural acoustic control

    OpenAIRE

    Oude Nijhuis, Marco H.H.; de Boer; Rao, Vittal S.

    2002-01-01

    This paper discusses the modeling of systems for active structural acoustic control. The finite element method is applied to model structures including the dynamics of piezoelectric sensors and actuators. A model reduction technique is presented to make the finite element model suitable for controller design. The reduced structural model is combined with an acoustic model which uses the radiation mode concept. For a test case consisting of a rectangular plate with one piezo patch the model re...

  16. Multi-element study in aluminium by activation analysis technique

    International Nuclear Information System (INIS)

    The instrumental activation analysis is a technique relatively quickly that help to know the elemental composition of materials. It is used mainly in the trace elements determination but in the case of major elements it is necessary to make some considerations as the different nuclear reactions carried out due to the neutron flux is a mixture of thermal and fast neutrons. This could be interpreted for the presence and or erroneous quantification about some elements. In this work, is described the way in which was analyzed a container piece with approximately a 85% of aluminium. The elements Zn, Mn, Sb, Ga, Cu, Cl and Sm were determined. (Author)

  17. A model for signal processing and predictive control of semi-active structural control system

    Indian Academy of Sciences (India)

    M-H Shih; W-P Sung; Ching-Jong Wang

    2009-06-01

    The theory for structural control has been well developed and applied to perform excellent energy dissipation using dampers. Both active and semi-active control systems may be used to decide on the optimal switch point of the damper based on the current and past structural responses to the excitation of external forces. However, numerous noises may occur when the control signals are accessed and transported thus causing a delay of the damper. Therefore, a predictive control technique that integrates an improved method of detecting the control signal based on the direction of the structural motion, and a calculator for detecting the velocity using the least-square polynomial regression is proposed in this research. Comparisons of the analytical data and experimental results show that this predictor is effective in switching the moving direction of the semi-active damper. This conclusion is further verified using the component and shaking table test with constant amplitude but various frequencies, and the El Centro earthquake test. All tests confirm that this predictive control technique is effective to alleviate the time delay problem of semi-active dampers. This predictive control technique promotes about 30% to 40% reduction of the structural displacement response and about 35% to 45% reduction of the structural acceleration response.

  18. Passivity-based control technique for integration of DG resources into the power grid

    DEFF Research Database (Denmark)

    Mehrasa, Majid; Adabi, M. Ebrahim; Pouresmaeil, Edris;

    2014-01-01

    This paper deals with a control method for integration of Distributed Generation (DG) sources to the power grid. The proposed control strategy has been designed based on passivity technique and provides compensation for the active, reactive, and harmonic current components of loads during...... the connection of DG link to the grid. The proper switching functions of interfaced converter have been defined based on the passivity method through the achieving space equations and suitable series damping injection. The proposed control plan is completed by setting suitable reference current components...... for the d and q axis in the control loop of DG, which are defined based on the objectives of proposed method. The effectiveness of the proposed control scheme is validated with injection of maximum available power from the DG resources to the power grid, correction of power factor between the grid current...

  19. Activities of the control services; Activites des services du controle

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    This paper summarizes the control activities of the technical service of electric power and big dams: annual examinations, administrative instructions (draining, floods, granting renewal), decennial examinations etc. (J.S.)

  20. Transmission and Reflection of Neutrons Using Foil Activation Technique

    International Nuclear Information System (INIS)

    A new neutron irradiation facility has been designed, constructed .and located at the Experimental Nuclear Physics Department, NRC, AEA, cairo. The neutrons were obtained from CNIF2 (Second Cairo Neutron Irradiation Facility) that is based on one 241 Am-Be(α, n) isotopic neutron source with a present activity of about 175 GBq results in a neutron yield of about 1.04 x107 n/s. The geometrical arrangements of the facility consider the safety and protection rules aspects. MCNP5 code is used to estimate radiation doses and neutron fluxes. This new irradiation facility provides fast and epithermal neutrons that can be used in basic research and industrial applications. The aim of the present work is to study the characteristics of this new irradiation facility and to develop methods able to use fast and epithermal neutron in some different applications. Experimental measurements for the transmission and reflection of neutrons were carried out via a number of hydrogenous materials using the activation foil technique. A comparison of the experimental results with that calculated by using Monte Carlo simulation method is presented Using the neutron transmission technique in combination with foil activation method, our arrangement is used to measure the total neutron microscopic cross-sections for some compounds. The facility is calibrated and suitable to estimate the hydrogen content H (wt %) and the weight ratios C/H in hydrocarbon materials and was used to measure these ratios for some Egyptian crude oil samples. A brief overview of the neutron activation analysis methods for elemental concentrations in bulk samples in natural conditions is presented.

  1. Active Control of Fan Noise

    Institute of Scientific and Technical Information of China (English)

    Nobuhiko YAMASAKI; Hirotoshi TAJIMA

    2008-01-01

    In the wake-rotor interaction fan noise, a number of the interacting modes at the blade passing frequency (BPF)and its harmonics are generated which are prescribed by the number of stator and rotor blades etc. In the present study, the dominant mode is tried to be suppressed by the secondary sound from the loudspeaker actuators. One of the novel features of the present system is the adoption of the control board with the Field Programmable Gate Array (FPGA) hardware and the LabVIEW software to synchronize the circumferentially installed loudspeaker actuators with the relative location of rotational blades under arbitrary fan rotational speeds. The experiments were conducted under the conditions of three rotational speeds of 2004, 3150, and 4002 [rpm]. The reduction in the sound pressure level (SPL) was observed for all three rotational speeds. The sound pressure level at the BPF was reduced approximately 13 [dB] for 2004 [rpm] case, but not so large reduction was attained for other cases probably due to the inefficiency of the loudspeaker actuators at high frequencies

  2. Active vibration control of lightweight floor systems

    Science.gov (United States)

    Baader, J.; Fontana, M.

    2016-04-01

    Wide-span and lightweight floors are often prone to structural vibrations due to their low resonance frequency and poor material damping. Their dynamic behaviour can be improved using passive, semi-active or active vibration control devices. The following article proposes a novel method for the controller synthesis for active vibration control. An existing passive TMD (tuned mass damper) is modelled and equipped with an actuator in order to provide more efficient damping. Using an iterative optimization approach under constraints, an optimal controller is found which minimizes a quadratic cost function in frequency domain. A simulation of an existing test bench shows that the active vibration control device is able to provide increased damping compared to the passive TMD.

  3. PID feedback controller used as a tactical asset allocation technique: The G.A.M. model

    Science.gov (United States)

    Gandolfi, G.; Sabatini, A.; Rossolini, M.

    2007-09-01

    The objective of this paper is to illustrate a tactical asset allocation technique utilizing the PID controller. The proportional-integral-derivative (PID) controller is widely applied in most industrial processes; it has been successfully used for over 50 years and it is used by more than 95% of the plants processes. It is a robust and easily understood algorithm that can provide excellent control performance in spite of the diverse dynamic characteristics of the process plant. In finance, the process plant, controlled by the PID controller, can be represented by financial market assets forming a portfolio. More specifically, in the present work, the plant is represented by a risk-adjusted return variable. Money and portfolio managers’ main target is to achieve a relevant risk-adjusted return in their managing activities. In literature and in the financial industry business, numerous kinds of return/risk ratios are commonly studied and used. The aim of this work is to perform a tactical asset allocation technique consisting in the optimization of risk adjusted return by means of asset allocation methodologies based on the PID model-free feedback control modeling procedure. The process plant does not need to be mathematically modeled: the PID control action lies in altering the portfolio asset weights, according to the PID algorithm and its parameters, Ziegler-and-Nichols-tuned, in order to approach the desired portfolio risk-adjusted return efficiently.

  4. Speed Control of Induction Motor Using New Sliding Mode Control Technique

    Directory of Open Access Journals (Sweden)

    Aamir Hashim Obeid Ahmed

    2010-06-01

    Full Text Available Induction Motors have been used as the workhorse in the industry for a long time due to its easy build, high robustness, and generally satisfactory efficiency. However, they are significantly more difficult to control than DC motors. One of the problems which might cause unsuccessful attempts for designing a proper controller would be the time varying nature of parameters and variables which might be changed while working with the motion systems. One of the best suggested solutions to solve this problem would be the use of Sliding Mode Control (SMC. This paper presents the design of a new controller for a vector control induction motor drive that employs an outer loop speed controller using SMC. Several tests were performed to evaluate the performance of the new controller method, and two other sliding mode controller techniques. From the comparative simulation results, one can conclude that the new controller law provides high performance dynamic characteristics and is robust with regard to plant parameter variations.

  5. Manually controlled neutron-activation system

    Science.gov (United States)

    Johns, R. A.; Carothers, G. A.

    1982-01-01

    A manually controlled neutron activation system, the Manual Reactor Activation System, was designed and built and has been operating at one of the Savannah River Plant's production reactors. With this system, samples can be irradiated for up to 24 hours and pneumatically transferred to a shielded repository for decay until their activity is low enough for them to be handled at a radiobench. The Manual Reactor Activation System was built to provide neutron activation of solid waste forms for the Alternative Waste Forms Leach Testing Program. Neutron activation of the bulk sample prior to leaching permits sensitive multielement radiometric analyses of the leachates.

  6. Smart materials and active noise and vibration control in vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Doppenberg, E.J.J.; Berkhoff, A.P.; Overbeek, M. van [TNO Institute of Applied Physics, Delft (Netherlands)

    2001-07-01

    Results are presented for the reduction of sound radiated from a structure using different control methodologies. Two approaches for active structural acoustic control are mentioned to reduce sound radiated by the structure: the acoustic approach or the vibro-acoustic approach. In both cases integrated actuators in structure materials are necessary to realise feasible products. Furthermore the development of an efficient shaker for Active Isolation techniques is described. The prototype of TNO TPD can produce a force of 400 N up to 250 Hz at a good performance-volume ratio. To enhance the robustness of the active control applications, the use of the subspace identification based control methods are developed. The robustness property of subspace identification methods forms the basis of an accurate model updating mechanism, using small size data batches. The performed simulations reveal excellent robustness performance under very general noise conditions or during operation of the control system. Furthermore the development of the techniques can be exploited to realise sound comfort requirements to enhance audible communications of vehicle related applications. To anticipate to these developments in the automotive industry, TNO has set up a Sound and Vibrations Research Centre with Twente University and a research program on Smart Panels with the Delft University. To investigate the potential markets and applications for sound comfort in the means of transportation, TNO-TPD and the Institute of Sound and Vibration Research in England (ISVR) have agreed on a cooperative venture to develop and realise 'active control of electroacoustics' (ACE). (orig.)

  7. UML activity diagrams in requirements specification of logic controllers

    Science.gov (United States)

    Grobelna, Iwona; Grobelny, Michał

    2015-12-01

    Logic controller specification can be prepared using various techniques. One of them is the wide understandable and user-friendly UML language and its activity diagrams. Using formal methods during the design phase increases the assurance that implemented system meets the project requirements. In the approach we use the model checking technique to formally verify a specification against user-defined behavioral requirements. The properties are usually defined as temporal logic formulas. In the paper we propose to use UML activity diagrams in requirements definition and then to formalize them as temporal logic formulas. As a result, UML activity diagrams can be used both for logic controller specification and for requirements definition, what simplifies the specification and verification process.

  8. Performance Enhancement of PID Controllers by Modern Optimization Techniques for Speed Control of PMBL DC Motor

    Directory of Open Access Journals (Sweden)

    M. Antony Freeda Rani

    2015-08-01

    Full Text Available Permanent Magnet Brushless DC motor (PMBL DC is used in a large number of industrial and automotive applications because of their high efficiency, compactness and excellent reliability. However to design an efficient PMBL DC motor, it is necessary to provide an effective controller that has to reduce the overshoot, settling and rise time. In this study, an improved PID controller has been designed by optimizing the parameters of PID controller based on two advanced optimization techniques ANFIS and Cuckoo Search optimization for speed control of a PMBL DC motor. The proposed approach has superior features, including easy implementation, stable convergence characteristic and good computational efficiency. The PMBL DC motor is modeled in SIMULINK implementing the algorithms in MATLAB and the performance evaluation has been studied.

  9. Active Noise Control in Propeller Aircraft

    OpenAIRE

    Johansson, Sven; Claesson, Ingvar

    2001-01-01

    A noisy environment dominated by low frequency noise can often be improved through the use of active noise control. This situation arises naturally in propeller aircraft where the propellers induce periodic low frequency noise inside the cabin. The cabin noise is typically rather high, and the passenger flight comfort could be improved considerably if this level were significantly reduced. This paper addresses same design aspects for multiple-reference active noise control systems based on th...

  10. Active Learning Techniques Applied to an Interdisciplinary Mineral Resources Course.

    Science.gov (United States)

    Aird, H. M.

    2015-12-01

    An interdisciplinary active learning course was introduced at the University of Puget Sound entitled 'Mineral Resources and the Environment'. Various formative assessment and active learning techniques that have been effective in other courses were adapted and implemented to improve student learning, increase retention and broaden knowledge and understanding of course material. This was an elective course targeted towards upper-level undergraduate geology and environmental majors. The course provided an introduction to the mineral resources industry, discussing geological, environmental, societal and economic aspects, legislation and the processes involved in exploration, extraction, processing, reclamation/remediation and recycling of products. Lectures and associated weekly labs were linked in subject matter; relevant readings from the recent scientific literature were assigned and discussed in the second lecture of the week. Peer-based learning was facilitated through weekly reading assignments with peer-led discussions and through group research projects, in addition to in-class exercises such as debates. Writing and research skills were developed through student groups designing, carrying out and reporting on their own semester-long research projects around the lasting effects of the historical Ruston Smelter on the biology and water systems of Tacoma. The writing of their mini grant proposals and final project reports was carried out in stages to allow for feedback before the deadline. Speakers from industry were invited to share their specialist knowledge as guest lecturers, and students were encouraged to interact with them, with a view to employment opportunities. Formative assessment techniques included jigsaw exercises, gallery walks, placemat surveys, think pair share and take-home point summaries. Summative assessment included discussion leadership, exams, homeworks, group projects, in-class exercises, field trips, and pre-discussion reading exercises

  11. Semi-active control of dynamically excited structures using active interaction control

    OpenAIRE

    Zhang, Yunfeng

    2001-01-01

    This thesis presents a family of semi-active control algorithms termed Active Interaction Control (AIC) used for response control of dynamically excited structures. The AIC approach has been developed as a semi﷓active means of protecting building structures against large earthquakes. The AIC algorithms include the Active Interface Damping (AID), Optimal Connection Strategy (OCS), and newly developed Tuned Interaction Damping (TID) algorithms. All of the AIC algorithms are founded upon ...

  12. Classifying controllers by activities : An exploratory study

    NARCIS (Netherlands)

    Verstegen, B.; De Loo, I.G.M.; Mol, P.; Slagter, K.; Geerkens, H.

    2007-01-01

    The goal of this paper is to discern variables (triggers) that affect a controller’s role in an organisation. Using survey data, groups of controllers are distinguished based on coherent combinations of activities. We find that controllers either operate as so-called ‘information adapters’ or ‘watch

  13. Active control of vibrations in pedestrian bridges

    OpenAIRE

    Álvaro Cunha; Carlos Moutinho

    1999-01-01

    This paper, apart from making a brief general reference to vibration problems in pedestrian bridges, as well as to the form of modelling of dynamic pedestrian loads, presents the use of a predictive control strategy for the numerical simulation of the dynamic response of actively controlled structures of this type. The consideration of this control strategy permitted the development of a computational model, which was applied to the study of a pedestrian cable-stayed bridge, in order to show ...

  14. Active and passive vibration control of structures

    CERN Document Server

    Spelsberg-Korspeter, Gottfried

    2014-01-01

    Active and Passive Vibration Control of Structures form an issue of very actual interest in many different fields of engineering, for example in the automotive and aerospace industry, in precision engineering (e.g. in large telescopes), and also in civil engineering. The papers in this volume bring together engineers of different background, and it fill gaps between structural mechanics, vibrations and modern control theory.  Also links between the different applications in structural control are shown.

  15. MATLAB Simulation of UPQC for Power Quality Mitigation Using an Ant Colony Based Fuzzy Control Technique.

    Science.gov (United States)

    Kumarasabapathy, N; Manoharan, P S

    2015-01-01

    This paper proposes a fuzzy logic based new control scheme for the Unified Power Quality Conditioner (UPQC) for minimizing the voltage sag and total harmonic distortion in the distribution system consequently to improve the power quality. UPQC is a recent power electronic module which guarantees better power quality mitigation as it has both series-active and shunt-active power filters (APFs). The fuzzy logic controller has recently attracted a great deal of attention and possesses conceptually the quality of the simplicity by tackling complex systems with vagueness and ambiguity. In this research, the fuzzy logic controller is utilized for the generation of reference signal controlling the UPQC. To enable this, a systematic approach for creating the fuzzy membership functions is carried out by using an ant colony optimization technique for optimal fuzzy logic control. An exhaustive simulation study using the MATLAB/Simulink is carried out to investigate and demonstrate the performance of the proposed fuzzy logic controller and the simulation results are compared with the PI controller in terms of its performance in improving the power quality by minimizing the voltage sag and total harmonic distortion.

  16. MATLAB Simulation of UPQC for Power Quality Mitigation Using an Ant Colony Based Fuzzy Control Technique

    Directory of Open Access Journals (Sweden)

    N. Kumarasabapathy

    2015-01-01

    Full Text Available This paper proposes a fuzzy logic based new control scheme for the Unified Power Quality Conditioner (UPQC for minimizing the voltage sag and total harmonic distortion in the distribution system consequently to improve the power quality. UPQC is a recent power electronic module which guarantees better power quality mitigation as it has both series-active and shunt-active power filters (APFs. The fuzzy logic controller has recently attracted a great deal of attention and possesses conceptually the quality of the simplicity by tackling complex systems with vagueness and ambiguity. In this research, the fuzzy logic controller is utilized for the generation of reference signal controlling the UPQC. To enable this, a systematic approach for creating the fuzzy membership functions is carried out by using an ant colony optimization technique for optimal fuzzy logic control. An exhaustive simulation study using the MATLAB/Simulink is carried out to investigate and demonstrate the performance of the proposed fuzzy logic controller and the simulation results are compared with the PI controller in terms of its performance in improving the power quality by minimizing the voltage sag and total harmonic distortion.

  17. A simulation benchmark to evaluate the performance of advanced control techniques in biological wastewater treatment plants

    Directory of Open Access Journals (Sweden)

    Sotomayor O.A.Z.

    2001-01-01

    Full Text Available Wastewater treatment plants (WWTP are complex systems that incorporate a large number of biological, physicochemical and biochemical processes. They are large and nonlinear systems subject to great disturbances in incoming loads. The primary goal of a WWTP is to reduce pollutants and the second goal is disturbance rejection, in order to obtain good effluent quality. Modeling and computer simulations are key tools in the achievement of these two goals. They are essential to describe, predict and control the complicated interactions of the processes. Numerous control techniques (algorithms and control strategies (structures have been suggested to regulate WWTP; however, it is difficult to make a discerning performance evaluation due to the nonuniformity of the simulated plants used. The main objective of this paper is to present a benchmark of an entire biological wastewater treatment plant in order to evaluate, through simulations, different control techniques. This benchmark plays the role of an activated sludge process used for removal of organic matter and nitrogen from domestic effluents. The development of this simulator is based on models widely accepted by the international community and is implemented in Matlab/Simulink (The MathWorks, Inc. platform. The benchmark considers plant layout and the effects of influent characteristics. It also includes a test protocol for analyzing the open and closed-loop responses of the plant. Examples of control applications in the benchmark are implemented employing conventional PI controllers. The following common control strategies are tested: dissolved oxygen (DO concentration-based control, respirometry-based control and nitrate concentration-based control.

  18. Applications of active adaptive noise control to jet engines

    Science.gov (United States)

    Shoureshi, Rahmat; Brackney, Larry

    1993-01-01

    During phase 2 research on the application of active noise control to jet engines, the development of multiple-input/multiple-output (MIMO) active adaptive noise control algorithms and acoustic/controls models for turbofan engines were considered. Specific goals for this research phase included: (1) implementation of a MIMO adaptive minimum variance active noise controller; and (2) turbofan engine model development. A minimum variance control law for adaptive active noise control has been developed, simulated, and implemented for single-input/single-output (SISO) systems. Since acoustic systems tend to be distributed, multiple sensors, and actuators are more appropriate. As such, the SISO minimum variance controller was extended to the MIMO case. Simulation and experimental results are presented. A state-space model of a simplified gas turbine engine is developed using the bond graph technique. The model retains important system behavior, yet is of low enough order to be useful for controller design. Expansion of the model to include multiple stages and spools is also discussed.

  19. An effective technique for isolating adult activated Schwann cells

    Institute of Scientific and Technical Information of China (English)

    Jifei Zhang; Lianhong Jin; Yuzhen Zhao

    2006-01-01

    BACKGROUND: Schwann cells (SCs) are neuroglial cells of peripheral nerve and play a key role in repairing peripheral nerve injury; therefore, it provides an important evidence for transplantation of SCs which are characterized by active proliferation and adult high-purity in vitro after nerve injury in clinic, and also develops a new therapeutic way for nerve injury.OBJECTIVE: To investigate an effective technique for isolating adult activated Schwann cells.DESIGN: Controlled observational study.SETTING: Mudanjiang Medical College.MATERIALS: The experiment was completed at the Department of Medical Genetics of Harbin Medical University from March 2003 to April 2005. Health female Wistar rats, aged 2 months, weighting 150-160 g, were randomly divided into 3 groups with 5 in each group.METHODS: The right sciatic nerves from 15 Wistar rats were exposed and transected at the mid thigh under pentobarbital anesthesia (4 mg/kg, I.p). Seven days later, the distal segments of the predegenerated nerves were removed and used to produce adult Schwann cell cultures. The distal segment of the predegenerated nerve, 20 mm in length, was resected. The nerve was cut into pieces 1 mm in length and incubated for 3 hours under CO2 at 37 ℃ with an enzyme mixture of 0.05% collagenase/dispase. Rats were divided into 3 groups:① Group 1: The nerve fragments were explanted in poly-L-lysine and laminin-coated dishes with BS medium from the 1st to the 6th day. On the 6th day, the fragments were removed into a new poly-L-lysine-laminin-coated dish and the BS medium was changed to BS with 10% FBS. The nerve fragments were replaced repeatedly in the same way in new dishes on the 12th and the 18th days. ②Group 2: For the first 3 days, the nerve fragments were fed with BS with 10% FBS. This medium was changed to BS medium on the third day. The nerve fragments were removed to another dish on day 6 and BS medium was changed to BS with 25 mL/L FBS. Hereafter the culture method was the same as

  20. HPLC-MS technique for radiopharmaceuticals analysis and quality control

    Science.gov (United States)

    Macášek, F.; Búriová, E.; Brúder, P.; Vera-Ruiz, H.

    2003-01-01

    Potentialities of liquid chromatography with mass spectrometric detector (MSD) were investigated with the objective of quality control of radiopharmaceuticals; 2-deoxy-2-[18F]fluoro-D-glucose (FDG) being an example. Screening of suitable MSD analytical lines is presented. Mass-spectrometric monitoring of acetonitrile— aqueous ammonium formate eluant by negatively charged FDG.HCO2 - ions enables isotope analysis (specific activity) of the radiopharmaceutical at m/z 227 and 226. Kryptofix® 222 provides an intense MSD signal of the positive ion associated with NH4 + at m/z 394. Expired FDG injection samples contain decomposition products from which at least one labelled by 18F and characterised by signal of negative ions at m/z 207 does not correspond to FDG fragments but to C5 decomposition products. A glucose chromatographic peak, characterised by m/z 225 negative ion is accompanied by a tail of a component giving a signal of m/z 227, which can belong to [18O]glucose; isobaric sorbitol signals were excluded but FDG-glucose association occurs in the co-elution of separation of model mixtures. The latter can actually lead to a convoluted chromatographic peak, but the absence of 18F makes this inconsistent. Quantification and validation of the FDG component analysis is under way.

  1. Active fault diagnosis by controller modification

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Niemann, Hans Henrik

    2010-01-01

    Two active fault diagnosis methods for additive or parametric faults are proposed. Both methods are based on controller reconfiguration rather than on requiring an exogenous excitation signal, as it is otherwise common in active fault diagnosis. For the first method, it is assumed that the system...... considered is controlled by an observer-based controller. The method is then based on a number of alternate observers, each designed to be sensitive to one or more additive faults. Periodically, the observer part of the controller is changed into the sequence of fault sensitive observers. This is done...... in a way that guarantees the continuity of transition and global stability using a recent result on observer parameterization. An illustrative example inspired by a field study of a drag racing vehicle is given. For the second method, an active fault diagnosis method for parametric faults is proposed...

  2. Active vibration control of basic structures using macro fiber composites

    Science.gov (United States)

    Yi, Guo; Wang, Jinming; Liu, Liwu; Liu, Yanju; Leng, Jinsong

    2011-03-01

    In the modern naval battle, as the anti-detection technique developing fleetly, enhancing submarine's hidden ability is becoming more and more important. However, in view of the worse control effect at low-frequency and weak adjustability to external influence, conventional passive vibration control can't satisfy the modern naval rigorous demands. Fortunately, active vibration control technology not only monitors the structure's real-time vibration, but also has more remarkable control effects and superior suitability. At the present time, it has a primary application in the vibration damping of ship engineering. In addition, due to functional materials rapidly developing, with the coming of piezoelectric composite materials, the advanced active control techniques have more applicability, lager damp amplitude and wider applied field, which basing on the piezoelectric-effect and inverse- piezoelectric-effect of piezoelectric materials. Especially, in the end of nineties, NASA had successfully manufactured the excellent macro fiber composite (MFC), which assembles actuating and sensing abilities. Comparing with the conventional piezoelectric ceramic materials, it provides the required durability, excellent flexibility, higher electromechanical coupling factors and stronger longitudinal actuating force by using interdigital electrodes. On the basis of the application of cantilever beam' active vibration control by using MFC actuators, this paper started with the mechanical characteristics of its actuating and sensing equations, and then investigated its piezoelectric feedback scale factor when equipped on the honeycomb aluminous panel. Finally, in order to validate the theoretical analysis method, the vibration control experiment of cantilever beam and honeycomb aluminous panel are built and tested with different activating force. The experimental results verify that MFC used in submarine structures' active vibration control are feasible and effective.

  3. THE CONTROL AND EVALUATION OF PROMOTIONAL ACTIVITIES

    Directory of Open Access Journals (Sweden)

    Felicia Sabou

    2012-01-01

    Full Text Available The paper focused on importance and benefits of control and evaluation of marketing activities. The control of efficiency review the assessment of the resources for marketing activity, checking also the efficiency of the human resources, advertising, promotion activities and distribution activities. In the analyse of human resources the most important ratio are: the average of costumers visits on a day, the number of custom order received from 100 visits, the number of new customers from a period, the number of lost customers from a period, the marketing human expenditures from all the sales.The strategic control is made to check if the objectives and the company strategy are adapted to the marketing environment.

  4. Determination and control of activity in radioactive waste as part of product control

    International Nuclear Information System (INIS)

    Research and development investigations have been performed for the control of the activity inventory using the following methods and techniques: non-destructive determination of actinide content in waste through passive neutron measurement including the examination of various parameters on detection efficiency; development of dissolution and decomposition techniques for the various waste groups; and development of methods for individual separation of radioisotopes and measurement of selected nuclides with main emphasis to Fe-55, Ni-59, Ni-63, Sr-90, I-129, Ra-226, Ra-228 and actinides. A comprehensive review of published literature concerning active and passive neutron emission as well as prompt and delayed neutron emission; dissolution and decomposition techniques; rapid chemical separation and measurements techniques for the above mentioned radionuclides; and basic radionuclide data is given. (orig.)

  5. Predictive Techniques for Spacecraft Cabin Air Quality Control

    Science.gov (United States)

    Perry, J. L.; Cromes, Scott D. (Technical Monitor)

    2001-01-01

    As assembly of the International Space Station (ISS) proceeds, predictive techniques are used to determine the best approach for handling a variety of cabin air quality challenges. These techniques use equipment offgassing data collected from each ISS module before flight to characterize the trace chemical contaminant load. Combined with crew metabolic loads, these data serve as input to a predictive model for assessing the capability of the onboard atmosphere revitalization systems to handle the overall trace contaminant load as station assembly progresses. The techniques for predicting in-flight air quality are summarized along with results from early ISS mission analyses. Results from groundbased analyses of in-flight air quality samples are compared to the predictions to demonstrate the technique's relative conservatism.

  6. Effect of Control Techniques on the Performance of Semiactive Dampers

    OpenAIRE

    Masi, John William

    2001-01-01

    A computer simulation is used to examine the effects that various control methods have on the performance of semiactive dampers in controlling the dynamics of a single suspension (quarter car) model. The level of dynamic control of this model has a direct bearing on the ride comfort and vehicle handling, when the single suspension is interpreted as a partial model of a vehicle. The dynamic results obtained when using two alternative semiactive control methods are compared to the results obt...

  7. Signal sampling techniques for data acquisition in process control

    NARCIS (Netherlands)

    Laan, Marten Derk van der

    1995-01-01

    In computing sytems employed for data acquisition and process control, communication with the controlled processes is mainly taking place via analog signal lines. In this situation, the quality of data acquired by A/D-converters and the generation of analog control signals by D/A-converters is of ma

  8. Activated mechanisms in amorphous silicon: an activation-relaxation-technique study

    OpenAIRE

    Mousseau, N.; Barkema, G. T.

    1999-01-01

    At low temperatures, dynamics in amorphous silicon occurs through a sequence of discrete activated events that locally reorganize the topological network. Using the activation-relaxation technique, a data base containing over 8000 such events is generated, and the events are analyzed with respect to their energy barrier and asymmetry, displacement and volume expansion/contraction. Special attention is paid to those events corresponding to diffusing coordination defects. The energetics is not ...

  9. Adaptive Piezoelectric Absorber for Active Vibration Control

    Directory of Open Access Journals (Sweden)

    Sven Herold

    2016-02-01

    Full Text Available Passive vibration control solutions are often limited to working reliably at one design point. Especially applied to lightweight structures, which tend to have unwanted vibration, active vibration control approaches can outperform passive solutions. To generate dynamic forces in a narrow frequency band, passive single-degree-of-freedom oscillators are frequently used as vibration absorbers and neutralizers. In order to respond to changes in system properties and/or the frequency of excitation forces, in this work, adaptive vibration compensation by a tunable piezoelectric vibration absorber is investigated. A special design containing piezoelectric stack actuators is used to cover a large tuning range for the natural frequency of the adaptive vibration absorber, while also the utilization as an active dynamic inertial mass actuator for active control concepts is possible, which can help to implement a broadband vibration control system. An analytical model is set up to derive general design rules for the system. An absorber prototype is set up and validated experimentally for both use cases of an adaptive vibration absorber and inertial mass actuator. Finally, the adaptive vibration control system is installed and tested with a basic truss structure in the laboratory, using both the possibility to adjust the properties of the absorber and active control.

  10. Active control for performance enhancement of electrically controlled rotor

    Institute of Scientific and Technical Information of China (English)

    Lu Yang; Wang Chao

    2015-01-01

    Electrically controlled rotor (ECR) system has the potential to enhance the rotor perfor-mance by applying higher harmonic flap inputs. In order to explore the feasibility and effectiveness for ECR performance enhancement using closed-loop control method, firstly, an ECR rotor perfor-mance analysis model based on helicopter flight dynamic model is established, which can reflect the performance characteristics of ECR helicopter at high advance ratio. Based on the simulation platform, an active control method named adaptive T-matrix algorithm is adopted to explore the feasibility and effectiveness for ECR performance enhancement. The simulation results verify the effectiveness of this closed-loop control method. For the sample ECR helicopter, about 3%rotor power reduction is obtained with the optimum 2/rev flap inputs at the advance ratio of 0.34. And through analyzing the distributions of attack of angle and drag in rotor disk, the underlying physical essence of ECR power reduction is cleared. Furthermore, the influence of the key control parameters, including convergence factor and weighting matrix, on the effectiveness of closed-loop control for ECR performance enhancement is explored. Some useful results are summarized, which can be used to direct the future active control law design of ECR performance enhancement.

  11. Active control for performance enhancement of electrically controlled rotor

    Directory of Open Access Journals (Sweden)

    Lu Yang

    2015-10-01

    Full Text Available Electrically controlled rotor (ECR system has the potential to enhance the rotor performance by applying higher harmonic flap inputs. In order to explore the feasibility and effectiveness for ECR performance enhancement using closed-loop control method, firstly, an ECR rotor performance analysis model based on helicopter flight dynamic model is established, which can reflect the performance characteristics of ECR helicopter at high advance ratio. Based on the simulation platform, an active control method named adaptive T-matrix algorithm is adopted to explore the feasibility and effectiveness for ECR performance enhancement. The simulation results verify the effectiveness of this closed-loop control method. For the sample ECR helicopter, about 3% rotor power reduction is obtained with the optimum 2/rev flap inputs at the advance ratio of 0.34. And through analyzing the distributions of attack of angle and drag in rotor disk, the underlying physical essence of ECR power reduction is cleared. Furthermore, the influence of the key control parameters, including convergence factor and weighting matrix, on the effectiveness of closed-loop control for ECR performance enhancement is explored. Some useful results are summarized, which can be used to direct the future active control law design of ECR performance enhancement.

  12. Herion Servo techniques with electronic control systems in hydraulic systems

    Energy Technology Data Exchange (ETDEWEB)

    Ehrath, M.

    1981-01-01

    A description of an electro-hydraulic control circuit for the fuel pump and the injection valve of a large diesel engine is presented. Pressures of 500-1000 bar must be controlled in diesel engines. The newly-developed electronically controlled injection system uses quick-action control valves, a further developed version of the high-response valves. Electronically controlled ignition systems offer the following advantages: improved fuel-air ratio and better combustion; improved injection parameters within the total load range of the engine, better adaption to changing operational and environmental conditions and to changing fuel quality, fewer and less complicated components, and increased operational safety.

  13. AC electric motors control advanced design techniques and applications

    CERN Document Server

    Giri, Fouad

    2013-01-01

    The complexity of AC motor control lies in the multivariable and nonlinear nature of AC machine dynamics. Recent advancements in control theory now make it possible to deal with long-standing problems in AC motors control. This text expertly draws on these developments to apply a wide range of model-based control designmethods to a variety of AC motors. Contributions from over thirty top researchers explain how modern control design methods can be used to achieve tight speed regulation, optimal energetic efficiency, and operation reliability and safety, by considering online state var

  14. Prospects of pharmaceuticals and biopharmaceuticals loaded microparticles prepared by double emulsion technique for controlled delivery.

    Science.gov (United States)

    Giri, Tapan Kumar; Choudhary, Chhatrapal; Ajazuddin; Alexander, Amit; Badwaik, Hemant; Tripathi, Dulal Krishna

    2013-04-01

    Several methods and techniques are potentially useful for the preparation of microparticles in the field of controlled drug delivery. The type and the size of the microparticles, the entrapment, release characteristics and stability of drug in microparticles in the formulations are dependent on the method used. One of the most common methods of preparing microparticles is the single emulsion technique. Poorly soluble, lipophilic drugs are successfully retained within the microparticles prepared by this method. However, the encapsulation of highly water soluble compounds including protein and peptides presents formidable challenges to the researchers. The successful encapsulation of such compounds requires high drug loading in the microparticles, prevention of protein and peptide degradation by the encapsulation method involved and predictable release, both rate and extent, of the drug compound from the microparticles. The above mentioned problems can be overcome by using the double emulsion technique, alternatively called as multiple emulsion technique. Aiming to achieve this various techniques have been examined to prepare stable formulations utilizing w/o/w, s/o/w, w/o/o, and s/o/o type double emulsion methods. This article reviews the current state of the art in double emulsion based technologies for the preparation of microparticles including the investigation of various classes of substances that are pharmaceutically and biopharmaceutically active. PMID:23960828

  15. THE GAME TECHNIQUE NTCHNIQUE STIMULATING LEARNING ACTIVITY OF JUNIOR STUDENTS SPECIALIZING IN ECONOMICS

    Directory of Open Access Journals (Sweden)

    Juri. S. Ezrokh

    2014-01-01

    Full Text Available The research is aimed at specifying and developing the modern control system of current academic achievements of junior university students; and the main task is to find the adequate ways for stimulating the junior students’ learning activities, and estimating their individual achievements.Methods: The author applies his own assessment method for estimating and stimulating students’ learning outcomes, based on the rating-point system of gradually obtained points building up a student’s integrated learning outcomes.Results: The research findings prove that implementation of the given method can increase the motivational, multiplicative and controlling components of the learning process.Scientific novelty: The method in question is based on the new original game approach to controlling procedures and stimulation of learning motivation of the economic profile students.Practical significance: The recommended technique can intensify the incentivebased training activities both in and outside a classroom, developing thereby students’ professional and personal qualities.

  16. Survey of Active Structural Control and Repair Using Piezoelectric Patches

    OpenAIRE

    Ahmed Abuzaid; Meftah Hrairi; M.S.I. Shaik Dawood

    2015-01-01

    The piezoelectric actuator has gained popularity over the last few years. Attention has been directed towards the study of their electromechanical response in active repair and the control of damaged structures. This has been made possible through the development of various numerical and analytical techniques for such studies. The shift of focus towards the piezoelectric based approaches has been due to their advantages, which include strategic cost benefits in maintenance, as well as an incr...

  17. Global synchronization of two parametrically excited systems using active control

    Energy Technology Data Exchange (ETDEWEB)

    Lei Youming [Department of Applied Mathematics, Northwestern Polytechnical University, Xi' an 710072 (China)] e-mail: leiyouming@nwpu.edu.cn; Xu Wei [Department of Applied Mathematics, Northwestern Polytechnical University, Xi' an 710072 (China)] e-mail: weixu@nwpu.edu.cn; Shen Jianwei [Department of Applied Mathematics, Northwestern Polytechnical University, Xi' an 710072 (China); Fang Tong [Department of Engineering Mechanics, Northwestern Polytechnical University, Xi' an 710072 (China)

    2006-04-01

    In this paper, we apply an active control technique to synchronize a kind of two parametrically excited chaotic systems. Based on Lyapunov stability theory and Routh-Hurwitz criteria, some generic sufficient conditions for global asymptotic synchronization are obtained. Illustrative examples on synchronization of two Duffing systems subject to a harmonic parametric excitation and that of two parametrically excited chaotic pendulums are considered here. Numerical simulations show the validity and feasibility of the proposed method.

  18. Active control of ionized boundary layers

    CERN Document Server

    Mendes, R V

    1997-01-01

    The challenging problems, in the field of control of chaos or of transition to chaos, lie in the domain of infinite-dimensional systems. Access to all variables being impossible in this case and the controlling action being limited to a few collective variables, it will not in general be possible to drive the whole system to the desired behaviour. A paradigmatic problem of this type is the control of the transition to turbulence in the boundary layer of fluid motion. By analysing a boundary layer flow for an ionized fluid near an airfoil, one concludes that active control of the transition amounts to the resolution of an generalized integro-differential eigenvalue problem. To cope with the required response times and phase accuracy, electromagnetic control, whenever possible, seems more appropriate than mechanical control by microactuators.

  19. Active control of an aircraft tail subject to harmonic excitation

    Institute of Scientific and Technical Information of China (English)

    M. Eissa; H. S. Bauomy; Y. A. Amer

    2007-01-01

    Vibration of structures is often an undesirable phenomena and should be avoided or controlled. There are two techniques to control the vibration of a system, that is,active and passive control techniques. In this paper, a negative feedback velocity is applied to a dynamical system, which is represented by two coupled second order nonlinear differ-ential equations having both quadratic and cubic nonlinear-ties. The system describes the vibration of an aircraft tail.The system is subjected to multi-external excitation forces.The method of multiple time scale perturbation is applied to solve the nonlinear differential equations and obtain approx-imate solutions up to third order of accuracy. The stability of the system is investigated applying frequency response equations. The effects of the different parameters are stud-ied numerically. Various resonance cases are investigated. A comparison is made with the available published work.

  20. The Sterile Insect Technique as a method of pest control

    International Nuclear Information System (INIS)

    In the Valencia community is doing one of the most ambitious project in the field of plant protection at European level: the fight against fruit fly, one of the most damaging pests of citrus and fruit; by Insect Technique Sterile. This technique consists of laboratory breeding and release into the fields of huge quantities of insects of the pest species that have previously been sterilized. Sterile insect looking for wild individuals of the same species to mate with them and the result is a clutch of viable eggs, causing a decrease in pest populations. After three years of application of the technique on an area of 150,000 hectares, the pest populations have been reduced by 90%. Other benefits have been the reduced used of insecticides and improved the quality of exported fruit. (Author)

  1. Actively Controlling Buffet-Induced Excitations

    Science.gov (United States)

    Moses, Robert W.; Pototzky, Anthony S.; Henderson, Douglas A.; Galea, Stephen C.; Manokaran, Donald S.; Zimcik, David G.; Wickramasinghe, Viresh; Pitt, Dale M.; Gamble, Michael A.

    2005-01-01

    High performance aircraft, especially those with twin vertical tails, encounter unsteady buffet loads when flying at high angles of attack. These loads result in significant random stresses, which may cause fatigue damage leading to restricted capabilities and availability of the aircraft. An international collaborative research activity among Australia, Canada and the United States, conducted under the auspices of The Technical Cooperation Program (TTCP) contributed resources toward a program that coalesced a broad range of technical knowledge and expertise into a single investigation to demonstrate the enhanced performance and capability of the advanced active BLA control system in preparation for a flight test demonstration. The research team investigated the use of active structural control to alleviate the damaging structural response to these loads by applying advanced directional piezoelectric actuators, the aircraft rudder, switch mode amplifiers, and advanced control strategies on an F/A-18 aircraft empennage. Some results of the full-scale investigation are presented herein.

  2. Higher-order techniques for some problems of nonlinear control

    Directory of Open Access Journals (Sweden)

    Sarychev Andrey V.

    2002-01-01

    Full Text Available A natural first step when dealing with a nonlinear problem is an application of some version of linearization principle. This includes the well known linearization principles for controllability, observability and stability and also first-order optimality conditions such as Lagrange multipliers rule or Pontryagin's maximum principle. In many interesting and important problems of nonlinear control the linearization principle fails to provide a solution. In the present paper we provide some examples of how higher-order methods of differential geometric control theory can be used for the study nonlinear control systems in such cases. The presentation includes: nonlinear systems with impulsive and distribution-like inputs; second-order optimality conditions for bang–bang extremals of optimal control problems; methods of high-order averaging for studying stability and stabilization of time-variant control systems.

  3. Active sampling technique to enhance chemical signature of buried explosives

    Science.gov (United States)

    Lovell, John S.; French, Patrick D.

    2004-09-01

    Deminers and dismounted countermine engineers commonly use metal detectors, ground penetrating radar and probes to locate mines. Many modern landmines have a very low metal content, which severely limits the effectiveness of metal detectors. Canines have also been used for landmine detection for decades. Experiments have shown that canines smell the explosives which are known to leak from most types of landmines. The fact that dogs can detect landmines indicates that vapor sensing is a viable approach to landmine detection. Several groups are currently developing systems to detect landmines by "sniffing" for the ultra-trace explosive vapors above the soil. The amount of material that is available to passive vapor sensing systems is limited to no more than the vapor in equilibrium with the explosive related chemicals (ERCs) distributed in the surface soils over and near the landmine. The low equilibrium vapor pressure of TNT in the soil/atmosphere boundary layer and the limited volume of the boundary layer air imply that passive chemical vapor sensing systems require sensitivities in the picogram range, or lower. ADA is working to overcome many of the limitations of passive sampling methods, by the use of an active sampling method that employs a high-powered (1,200+ joules) strobe lamp to create a highly amplified plume of vapor and/or ERC-bearing fine particulates. Initial investigations have demonstrated that this approach can amplify the detectability of TNT by two or three orders of magnitude. This new active sampling technique could be used with any suitable explosive sensor.

  4. Quality Assurance and Control in Laboratory using Neutron Activation Analysis

    International Nuclear Information System (INIS)

    In accordance with the increment of international trade associated with the worldwide globalization, the importance of quality assurance and control for the commodity produced from one's own country has been stressed. ISO (International Organization for Standards) defines quality control as 'the operational techniques and activities that are used to fulfill the requirements for quality'. Since 1996, the HANARO research reactor in the Korea Atomic Energy Research Institute has been operated thereafter initial critical operation on April 1995. Neutron activation analysis system and applied techniques which is one of a nuclear analytical technologies using reactor neutrons has been developed for user's supporting and the establishment of the quality system for a measurement and analysis, testing and inspection was implemented successfully. On the basis of the qualified NAA system, the test and measurement of more than 1500 samples which is requested from 30 organizations including industrial companies, universities and institutes carried out in NAA laboratory annually. Moreover, as the goal of mutual recognition agreement (MRA) which can be removed a technical barrier in international trade, the objectivity and the confidence of analytical quality in NAA laboratory became established through the installation of international accreditation system by implementing analytical quality system in accordance with international standards in 2001. The aim of the report was to summarize the technical management of introduction, methods and the results for a quality control and assurance which should be performed in NAA technique using the HANARO research reactor. The report will help building up effective quality control strategy in the future

  5. Jacket Substructure Fatigue Mitigation through Active Control

    DEFF Research Database (Denmark)

    Hanis, Tomas; Natarajan, Anand

    2014-01-01

    to the fatigue design loads on the braces of the jacket. Since large wind turbines of 10MW rating have low rotor speeds (p), the modal frequencies of the sub structures approach 3p at low wind speeds, which leads to a modal coupling and resonance. Therefore an active control system is developed which provides...... sufficient structural damping and consequently a fatigue reduction at the substructure. The resulting reduction in fatigue design loads on the jacket structure based on the active control system is presented....

  6. Novel USDA Mosquito Control Techniques for the US Military

    Science.gov (United States)

    Novel techniques that we developed at the USDA to protect deployed military troops from the threat of vector-borne diseases are described. Some of the methods developed included (1) novel military personal protection methods, (2) barrier treatments of artificial materials and natural vegetation, and...

  7. Mosquito Control Techniques Developed for the US Military

    Science.gov (United States)

    The USDA developed and field tested new techniques to reduce the risk to deployed military troops from vector-borne diseases. Some of the methods developed included (1) novel military personal protection methods, (2) barrier treatments of artificial materials and natural vegetation, and (3) ground a...

  8. Active steering control strategy for articulated vehicles

    Institute of Scientific and Technical Information of China (English)

    Kyong-il KIM; Hsin GUAN; Bo WANG; Rui GUO; Fan LIANG

    2016-01-01

    To improve maneuverability and stability of articulated vehicles, we design an active steering controller, including tractor and trailer controllers, based on linear quadratic regulator (LQR) theory. First, a three-degree-of-freedom (3-DOF) model of the tractor-trailer with steered trailer axles is built. The simulated annealing particle swarm optimization (SAPSO) algorithm is applied to identify the key parameters of the model under specified vehicle speed and steering wheel angle. Thus, the key pa-rameters of the simplified model can be obtained according to the vehicle conditions using an online look-up table and interpola-tion. Simulation results show that vehicle parameter outputs of the simplified model and TruckSim agree well, thus providing the ideal reference yaw rate for the controller. Then the active steering controller of the tractor and trailer based on LQR is designed to follow the desired yaw rate and minimize their side-slip angle of the center of gravity (CG) at the same time. Finally, simulation tests at both low speed and high speed are conducted based on the TruckSim-Simulink program. The results show significant effects on the active steering controller on improving maneuverability at low speed and lateral stability at high speed for the articulated vehicle. The control strategy is applicable for steering not only along gentle curves but also along sharp curves.

  9. Span of Control and Span of Activity

    OpenAIRE

    Oriana Bandiera; Andrea Prat; Raffaella Sadun; Julie Wulf

    2012-01-01

    For both practitioners and researchers, span of control plays an important role in defining and understanding the role of the CEO. In this paper, we combine organizational chart information for a sample of 65 companies with detailed data on how their CEOs allocate their work time, which we define as their span of activity. Span of activity provides a direct measure of the CEO's management style, including the attention devoted to specific subordinates and functions, the time devoted to indivi...

  10. Capital Control, Debt Financing and Innovative Activity

    OpenAIRE

    Czarnitzki, Dirk; Kraft, Kornelius

    2009-01-01

    "The present paper discusses the effects of dispersed versus concentrated capital ownership on investment into innovative activity. While the market for equity capital might exert insufficient control on top managements’ behavior, this weakness may be mitigated by a suitable degree of debt financing. We report the results of an empirical study on the determinants of innovative activity measured by patent applications. Using a large sample of German manufacturing firms, we find that companies ...

  11. Design and Comparison Direct Torque Control Techniques for Induction Motors

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Kazmierkowski, Marian P.; Zelechowski, Marcin;

    2005-01-01

    In this paper a comparison of two significant control methods of induction motor are presented. The first one is a classical Direct Torque and Flux Control (DTC) and is compared with a scheme, which uses Space Vector Modulator (DTC-SVM). A comparison in respect to dynamic and steady state...

  12. Analytical techniques and quality control in biomedical trace element research

    DEFF Research Database (Denmark)

    Heydorn, K.

    1994-01-01

    The small number of analytical results in trace element research calls for special methods of quality control. It is shown that when the analytical methods are in statistical control, only small numbers of duplicate or replicate results are needed to ascertain the absence of systematic errors cau...

  13. Linear Control Technique for Anti-Lock Braking System

    Directory of Open Access Journals (Sweden)

    Chankit Jain

    2014-08-01

    Full Text Available Antilock braking systems are used in modern cars to prevent the wheels from locking after brakes are applied. The dynamics of the controller needed for antilock braking system depends on various factors. The vehicle model often is in nonlinear form. Controller needs to provide a controlled torque necessary to maintain optimum value of the wheel slip ratio. The slip ratio is represented in terms of vehicle speed and wheel rotation. In present work first of all system dynamic equations are explained and a slip ratio is expressed in terms of system variables namely vehicle linear velocity and angular velocity of the wheel. By applying a bias braking force system, response is obtained using Simulink models. Using the linear control strategies like PI-type the effectiveness of maintaining desired slip ratio is tested. It is always observed that a steady state error of 10% occurring in all the control system models.

  14. Software factory techniques applied to Process Control at CERN

    CERN Multimedia

    Dutour, MD

    2007-01-01

    The CERN Large Hadron Collider (LHC) requires constant monitoring and control of quantities of parameters to guarantee operational conditions. For this purpose, a methodology called UNICOS (UNIfied Industrial COntrols Systems) has been implemented to standardize the design of process control applications. To further accelerate the development of these applications, we migrated our existing UNICOS tooling suite toward a software factory in charge of assembling project, domain and technical information seamlessly into deployable PLC (Programmable logic Controller) – SCADA (Supervisory Control And Data Acquisition) systems. This software factory delivers consistently high quality by reducing human error and repetitive tasks, and adapts to user specifications in a cost-efficient way. Hence, this production tool is designed to encapsulate and hide the PLC and SCADA target platforms, enabling the experts to focus on the business model rather than specific syntaxes and grammars. Based on industry standard software...

  15. The evolution of tooling, techniques, and quality control for accelerator dipole magnet cables

    International Nuclear Information System (INIS)

    The present generation of particle accelerators are utilizing the flattened, compacted, single layer cable design introduced nearly 20 years ago at Rutherford Laboratory. However, the requirements for current density, filament size, dimensional control long lengths, and low current degradation are much more stringent for the present accelerators compared with the earlier Tevatron and HERA accelerators. Also, in order to achieve higher field strengths with efficient use of superconductor, the new designs require wider cables with more strands. These requirements have stimulated an active research effort which has led to significant improvements in critical current density and conductor manufacturing. In addition they have stimulated the development of new cabling techniques, improved tooling, and better measurement techniques. The need to produce over 20 million meters of cable has led to the development of high speed cabling machines and on-line quality assurance measurements. These new developments will be discussed, and areas still requiring improvement will be identified

  16. Advanced design technique of human-machine interfaces for PLC control of complex systems

    Directory of Open Access Journals (Sweden)

    Árpád-István Sütő

    2008-05-01

    Full Text Available Touchscreen operator panels proved to be a convenient succesor for clasical operator panels for implementing human-machine interfaces (HMIs in programmable logic controllers (PLC systems. The paper introduces a new technique for HMIs design in such systems, based on the idea of touchscreens replication. This redundancy allow actions which are not possible within the menus and sub-menus of a single touchscreen. Its strenght is revealed especially in complex systems, where operators can easily be overwhelmed by the huge amount of process information. The technique was applied on a mill tube rolling installation. The results also proved an increase of system security and zero downtime for HMI maintenance activities.

  17. Welfare aspects of vertebrate pest control and culling: ranking control techniques for humaneness.

    Science.gov (United States)

    Littin, K; Fisher, P; Beausoleil, N J; Sharp, T

    2014-04-01

    The management of vertebrate pests depends on the use of traps, pesticides, repellents and other methods, each of which can cause varying levels of pain and other negative experiences to animals. Vertebrate pest control is essential for managing the impacts of unwanted or over-abundant animals on human and animal health, ecological balance and economic interests. As the need for this management is unlikely to diminish over time, a framework has been developed for assessing the humaneness of each technique by considering their negative impacts on animal welfare so that these can be included in decision-making about the selection of techniques for a specific control operation. This information can also support evidence-based regulations directed at managing such animal welfare impacts. In this paper, the authors discuss this assessment framework, briefly review two assessments conducted using the framework and discuss ways in which Competent Authorities and others can use it and other means to improve animal welfare in vertebrate pest management.

  18. Active Vibration Control of Piezolaminated Smart Beams

    Directory of Open Access Journals (Sweden)

    V. Balamurugan

    2001-04-01

    Full Text Available This paper deals with the active vibration control of beam like structures with distributed piezoelectric sensor and actuator layers bonded on top and bottom surfaces of the beam. A finite element model based on Euler-Bernoulli beam theory has been developed. The contribution of the piezoelectric sensor and actuator layers on the mass and stiffness of the beam is considered. Three types of classical control strategies, namely direct proportional feedback, constant-gain negative velocity feedback and Lyapunov feedback and an optimal control strategy, linear quadratic regulator (LQR scheme are applied to study their control effectiveness. Also, the control performance with different types of loading, such as impulse loading, step loading, harmonic and random loading is studied

  19. Exogenous bleaching evaluation on dentin using chemical activated technique compared with diode laser technique

    International Nuclear Information System (INIS)

    This in vitro study compared the results of different exogenous bleaching proceedings on dentin after treatment of enamel surface. Thirty human canine were hewn preserving the vestibular half of the crown and 3 mm of root, showing a vestibular-lingual thickness average of 3,5 mm, measuring in the third middle of the crown. Ali teeth were maintained in wet chamber during the experiment. Digital photographs were taken of the dentin surface at 3 experimental times (LI: initial record, L0: immediate pos-bleaching record and L 15: 15 days after bleaching). The teeth were divided into 3 experimental groups of 10 teeth in each. The Control Group did not receive any kind of treatment. The Laser Group received 2 session of laser bleaching, with 3 applications each, using 35% hydrogen peroxide, activated by diode laser during 30 seconds, by scanning the enamel surface from incisal edge to the top of the crown, from mesial to distal portion of the crown and circularly, each movement during 10 seconds. The following parameters being adopted: wavelength of 808 nm, power of 1,5 W and optic fiber with 600 μm (core). The Peroxide Group received 28 daily applications, during 4 hours each application, using 16% carbamide peroxide. The bleaching records were analysed using a computer, through RGBK (red, green , blue and black). The K averages (K=100% for black and K=0% for white) of the records for Control Group were: LI=50,1 %, L0=50,3% and L 15=50,6%. For Laser Group the K averages were LI=48,5%, L0=50,0% and L 15=47,7%. And for the Peroxide Group were LI=50,5%, L0=35,9% and L 15=37,3%. The statistical analysis showed no significant difference of the K between the Control Group and the Laser Group, as to LI, L0 and L 15. Only Peroxide Group showed significant statistical difference between LI with L0 and L 15 (0,1%), and L0 in comparison with L 15 did not show any difference. (author)

  20. An activated fluid stream - New techniques for cold water cleaning

    OpenAIRE

    Birkin, Peter; Offin, Douglas; Leighton, Timothy

    2015-01-01

    Electrochemical, acoustic and imaging techniques are used to characterise surface cleaning with particular emphasis on the understanding of the key phenomena relevant to surface cleaning. A range of novel techniques designed to enhance and monitor the effective cleaning of a solid/liquid interface is presented. Among the techniques presented, mass transfer of material to a sensor embedded in a surface is demonstrated to be useful in the further exploration of ultrasonic cleaning of high asp...

  1. A 21st century technique for food control: Electronic noses

    Energy Technology Data Exchange (ETDEWEB)

    Peris, Miguel, E-mail: mperist@qim.upv.es [Departamento de Quimica, Universidad Politecnica de Valencia, 46071 Valencia (Spain); Escuder-Gilabert, Laura [Departamento de Quimica Analitica, Universitat de Valencia, C/Vicente Andres Estelles s/n, E-46100 Burjasot, Valencia (Spain)

    2009-04-06

    This work examines the main features of modern electronic noses (e-noses) and their most important applications in food control in this new century. The three components of an electronic nose (sample handling system, detection system, and data processing system) are described. Special attention is devoted to the promising mass spectrometry based e-noses, due to their advantages over the more classical gas sensors. Applications described include process monitoring, shelf-life investigation, freshness evaluation, authenticity assessment, as well as other general aspects of the utilization of electronic noses in food control. Finally, some interesting remarks concerning the strengths and weaknesses of electronic noses in food control are also mentioned.

  2. Techniques for increasing the reliability of accelerator control system electronics

    International Nuclear Information System (INIS)

    As the physical size of modern accelerators becomes larger and larger, the number of required control system circuit boards increases, and the probability of one of those circuit boards failing while in service also increases. In order to do physics, the experimenters need the accelerator to provide beam reliably with as little down time as possible. With the advent of colliding beams physics, reliability becomes even more important due to the fact that a control system failure can cause the loss of painstakingly produced antiprotons. These facts prove the importance of keeping reliability in mind when designing and maintaining accelerator control system electronics

  3. A 21st century technique for food control: Electronic noses

    International Nuclear Information System (INIS)

    This work examines the main features of modern electronic noses (e-noses) and their most important applications in food control in this new century. The three components of an electronic nose (sample handling system, detection system, and data processing system) are described. Special attention is devoted to the promising mass spectrometry based e-noses, due to their advantages over the more classical gas sensors. Applications described include process monitoring, shelf-life investigation, freshness evaluation, authenticity assessment, as well as other general aspects of the utilization of electronic noses in food control. Finally, some interesting remarks concerning the strengths and weaknesses of electronic noses in food control are also mentioned.

  4. Use of Nuclear Techniques in Food, Agriculture and Pest Control

    International Nuclear Information System (INIS)

    The so-called Nuclear Techniques used in agriculture are of two distinct types but both based on the special characteristics of radio-isotopes which give off radiation or on isotopes which are heavier than the normal element. One type of application uses the radiation given off by isotopes to enable the detection of individual atoms in infinitely small amounts of matter. With this technique we can e.g. follow the travels of fertilizer elements in the soil, into and throughout the crop plant or the travels of animal nutrient atoms throughout the animal and their deposition in milk and meat. This has resulted in enormous advances in crop and livestock research. Very minute traces of pesticides and their residues can be detected in food, in plants and animals and in the environment enabling the development of measures to reduce harmful effects

  5. Modeling and vibration control of an active membrane mirror

    Science.gov (United States)

    Ruggiero, Eric J.; Inman, Daniel J.

    2009-09-01

    The future of space satellite technology lies in ultra-large mirrors and radar apertures for significant improvements in imaging and communication bandwidths. The availability of optical-quality membranes drives a parallel effort for structural models that can capture the dominant dynamics of large, ultra-flexible satellite payloads. Unfortunately, the inherent flexibility of membrane mirrors wreaks havoc with the payload's on-orbit stability and maneuverability. One possible means of controlling these undesirable dynamics is by embedding active piezoelectric ceramics near the boundary of the membrane mirror. In doing so, active feedback control can be used to eliminate detrimental vibration, perform static shape control, and evaluate the health of the structure. The overall motivation of the present work is to design a control system using distributed bimorph actuators to eliminate any detrimental vibration of the membrane mirror. As a basis for this study, a piezoceramic wafer was attached in a bimorph configuration near the boundary of a tensioned rectangular membrane sample. A finite element model of the system was developed to capture the relevant system dynamics from 0 to 300 Hz. The finite element model was compared against experimental results, and fair agreement found. Using the validated finite element models, structural control using linear quadratic regulator control techniques was then used to numerically demonstrate effective vibration control. Typical results show that less than 12 V of actuation voltage is required to eliminate detrimental vibration of the membrane samples in less than 15 ms. The functional gains of the active system are also derived and presented. These spatially descriptive control terms dictate favorable regions within the membrane domain for placing sensors and can be used as a design guideline for structural control applications. The results of the present work demonstrate that thin plate theory is an appropriate modeling

  6. MODELING MERCURY CONTROL WITH POWDERED ACTIVATED CARBON

    Science.gov (United States)

    The paper presents a mathematical model of total mercury removed from the flue gas at coal-fired plants equipped with powdered activated carbon (PAC) injection for Mercury control. The developed algorithms account for mercury removal by both existing equipment and an added PAC in...

  7. DNA-based control of protein activity.

    Science.gov (United States)

    Engelen, W; Janssen, B M G; Merkx, M

    2016-03-01

    DNA has emerged as a highly versatile construction material for nanometer-sized structures and sophisticated molecular machines and circuits. The successful application of nucleic acid based systems greatly relies on their ability to autonomously sense and act on their environment. In this feature article, the development of DNA-based strategies to dynamically control protein activity via oligonucleotide triggers is discussed. Depending on the desired application, protein activity can be controlled by directly conjugating them to an oligonucleotide handle, or expressing them as a fusion protein with DNA binding motifs. To control proteins without modifying them chemically or genetically, multivalent ligands and aptamers that reversibly inhibit their function provide valuable tools to regulate proteins in a noncovalent manner. The goal of this feature article is to give an overview of strategies developed to control protein activity via oligonucleotide-based triggers, as well as hurdles yet to be taken to obtain fully autonomous systems that interrogate, process and act on their environments by means of DNA-based protein control. PMID:26812623

  8. Wind Turbine Rotors with Active Vibration Control

    DEFF Research Database (Denmark)

    Svendsen, Martin Nymann

    This thesis presents a framework for structural modeling, analysis and active vibration damping of rotating wind turbine blades and rotors. A structural rotor model is developed in terms of finite beam elements in a rotating frame of reference. The element comprises a representation of general...... formulation. The element provides an accurate representation of the eigenfrequencies and whirling modes of the gyroscopic system, and identifies lightly damped edge-wise modes. By adoption of a method for active, collocated resonant vibration of multi-degree-of-freedom systems it is demonstrated...... that these are geometrically well separated. For active vibration control in three-bladed wind turbine rotors the present work presents a resonance-based method for groups of one collective and two whirling modes. The controller is based on the existing resonant format and introduces a dual system targeting the collective...

  9. Active control of transmitted sound in buildings

    Science.gov (United States)

    Thompsett, Russell Harvey George

    The problem of noise from neighbours has increased dramatically over the last few years. Many of the noise complaints are due to the high level, low frequency noise from modern stereo equipment, and are often described in terms of the low frequency characteristics of the music; the repetitive, booming, bass beat. The objective of this research was to establish the feasibility of applying active noise control to alleviate this problem. The initial approach was to evaluate the possibility of exploiting the dominance of individual modes in the response of rooms at low frequency to effect global control. However, initial investigations using a modal model of the sound field revealed that this would be difficult due to the contribution of many acoustic modes excited off resonance. This conclusion was supported by measurements of acoustic room responses in typical buildings, illustrating a non-resonant characteristic. Consequently, attention was turned to the feasibility of using local active control systems to create zones of quiet by concentrating control at a specific location near the observers ears, for example in a seat headrest, or near the pillows of a bed. The lack of a reference signal in either approach requires the use of a feedback control strategy. With a typically non-resonant system, the predictability in the disturbance necessary for successful feedback control must be contained in the primary excitation, namely the music. Examples of different music styles were investigated and of those with the potential to be a nuisance surprisingly few were significantly more predictable than a random disturbance. As expected the most encouraging control performance simulations were found for modern dance music, with a strong repetitive beat. A real-time, local controller was demonstrated in the laboratory with such a disturbance signal and the properties of the quiet zone were measured. The subjective response when hearing the controller in operation was found to be

  10. Active control of multiple resistive wall modes

    International Nuclear Information System (INIS)

    A two-dimensional array of saddle coils at Mc poloidal and Nc toroidal positions is used on the EXTRAP T2R reversed-field pinch (Brunsell P R et al 2001 Plasma Phys. Control. Fusion 43 1457) to study active control of resistive wall modes (RWMs). Spontaneous growth of several RWMs with poloidal mode number m = 1 and different toroidal mode number n is observed experimentally, in agreement with linear MHD modelling. The measured plasma response to a controlled coil field and the plasma response computed using the linear circular cylinder MHD model are in quantitative agreement. Feedback control introduces a linear coupling of modes with toroidal mode numbers n, n' that fulfil the condition |n - n'| = Nc. Pairs of coupled unstable RWMs are present in feedback experiments with an array of Mc x Nc = 4 x 16 coils. Using intelligent shell feedback, the coupled modes are generally not controlled even though the field is suppressed at the active coils. A better suppression of coupled modes may be achieved in the case of rotating modes by using the mode control feedback scheme with individually set complex gains. In feedback with a larger array of Mc x Nc = 4 x 32 coils, the coupling effect largely disappears, and with this array, the main internal RWMs n = -11, -10, +5, +6 are all simultaneously suppressed throughout the discharge (7-8 wall times). With feedback there is a two-fold extension of the pulse length, compared to discharges without feedback

  11. Active control of multiple resistive wall modes

    Science.gov (United States)

    Brunsell, P. R.; Yadikin, D.; Gregoratto, D.; Paccagnella, R.; Liu, Y. Q.; Bolzonella, T.; Cecconello, M.; Drake, J. R.; Kuldkepp, M.; Manduchi, G.; Marchiori, G.; Marrelli, L.; Martin, P.; Menmuir, S.; Ortolani, S.; Rachlew, E.; Spizzo, G.; Zanca, P.

    2005-12-01

    A two-dimensional array of saddle coils at Mc poloidal and Nc toroidal positions is used on the EXTRAP T2R reversed-field pinch (Brunsell P R et al 2001 Plasma Phys. Control. Fusion 43 1457) to study active control of resistive wall modes (RWMs). Spontaneous growth of several RWMs with poloidal mode number m = 1 and different toroidal mode number n is observed experimentally, in agreement with linear MHD modelling. The measured plasma response to a controlled coil field and the plasma response computed using the linear circular cylinder MHD model are in quantitive agreement. Feedback control introduces a linear coupling of modes with toroidal mode numbers n, n' that fulfil the condition |n - n'| = Nc. Pairs of coupled unstable RWMs are present in feedback experiments with an array of Mc × Nc = 4 × 16 coils. Using intelligent shell feedback, the coupled modes are generally not controlled even though the field is suppressed at the active coils. A better suppression of coupled modes may be achieved in the case of rotating modes by using the mode control feedback scheme with individually set complex gains. In feedback with a larger array of Mc × Nc = 4 × 32 coils, the coupling effect largely disappears, and with this array, the main internal RWMs n = -11, -10, +5, +6 are all simultaneously suppressed throughout the discharge (7 8 wall times). With feedback there is a two-fold extension of the pulse length, compared to discharges without feedback.

  12. Study on modeling of vehicle dynamic stability and control technique

    Institute of Scientific and Technical Information of China (English)

    GAO Yun-ting; LI Pan-feng

    2012-01-01

    In order to solve the problem of enhancing the vehicle driving stability and safety,which has been the hot question researched by scientific and engineering in the vehicle industry,the new control method was investigated.After the analysis of tire moving characteristics and the vehicle stress analysis,the tire model based on the extension pacejka magic formula which combined longitudinal motion and lateral motion was developed and a nonlinear vehicle dynamical stability model with seven freedoms was made.A new model reference adaptive control project which made the slip angle and yaw rate of vehicle body as the output and feedback variable in adjusting the torque of vehicle body to control the vehicle stability was designed.A simulation model was also built in Matlab/Simulink to evaluate this control project.It was made up of many mathematical subsystem models mainly including the tire model module,the yaw moment calculation module,the center of mass parameter calculation module,tire parameter calculation module of multiple and so forth.The severe lane change simulation result shows that this vehicle model and the model reference adaptive control method have an excellent performance.

  13. GPU-Based Optimal Control Techniques for Resistive Wall Mode Control on DIII-D

    Science.gov (United States)

    Clement, M.; Navratil, G. A.; Hanson, J. M.; Strait, E. J.

    2014-10-01

    The DIII-D tokamak can excite strong, locked or nearly locked kink modes whose rotation frequencies do not evolve quickly and are slow compared to their growth rates. To control such modes, DIII-D plans to implement a Graphical Processing Unit (GPU) based feedback control system in a low-latency architecture based on system developed on the HBT-EP tokamak. Up to 128 local magnetic sensors will be used to extrapolate the state of the rotating kink mode, which will be used by the feedback algorithm to calculate the required currents for the internal and/or external control coils. Offline techniques for resolving the mode structure of the resistive wall mode (RWM) will be presented and compared along with the proposed GPU implementation scheme and potential real-time estimation algorithms for RWM feedback. Work supported by the US Department of Energy under DE-FG02-07ER54917, DE-FG02-04ER54761, and DE-FC02-04ER54698.

  14. Respiratory protective device design using control system techniques

    Science.gov (United States)

    Burgess, W. A.; Yankovich, D.

    1972-01-01

    The feasibility of a control system analysis approach to provide a design base for respiratory protective devices is considered. A system design approach requires that all functions and components of the system be mathematically identified in a model of the RPD. The mathematical notations describe the operation of the components as closely as possible. The individual component mathematical descriptions are then combined to describe the complete RPD. Finally, analysis of the mathematical notation by control system theory is used to derive compensating component values that force the system to operate in a stable and predictable manner.

  15. Active vibration control of nonlinear benchmark buildings

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xing-de; CHEN Dao-zheng

    2007-01-01

    The present nonlinear model reduction methods unfit the nonlinear benchmark buildings as their vibration equations belong to a non-affine system. Meanwhile,the controllers designed directly by the nonlinear control strategy have a high order, and they are difficult to be applied actually. Therefore, a new active vibration control way which fits the nonlinear buildings is proposed. The idea of the proposed way is based on the model identification and structural model linearization, and exerting the control force to the built model according to the force action principle. This proposed way has a better practicability as the built model can be reduced by the balance reduction method based on the empirical Grammian matrix. A three-story benchmark structure is presented and the simulation results illustrate that the proposed method is viable for the civil engineering structures.

  16. Actively controlled vibration welding system and method

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Wayne W.; Kang, Bongsu; Tan, Chin-An

    2013-04-02

    A vibration welding system includes a controller, welding horn, an active material element, and anvil assembly. The assembly may include an anvil body connected to a back plate and support member. The element, e.g., a piezoelectric stack or shape memory alloy, is positioned with respect to the assembly. The horn vibrates in a desirable first direction to form a weld on a work piece. The element controls any vibrations in a second direction by applying calibrated response to the anvil body in the second direction. A method for controlling undesirable vibrations in the system includes positioning the element with respect to the anvil assembly, connecting the anvil body to the support member through the back plate, vibrating the horn in a desirable first direction, and transmitting an input signal to the element to control vibration in an undesirable second direction.

  17. Control Systems Cyber Security Standards Support Activities

    Energy Technology Data Exchange (ETDEWEB)

    Robert Evans

    2009-01-01

    The Department of Homeland Security’s Control Systems Security Program (CSSP) is working with industry to secure critical infrastructure sectors from cyber intrusions that could compromise control systems. This document describes CSSP’s current activities with industry organizations in developing cyber security standards for control systems. In addition, it summarizes the standards work being conducted by organizations within the sector and provides a brief listing of sector meetings and conferences that might be of interest for each sector. Control systems cyber security standards are part of a rapidly changing environment. The participation of CSSP in the development effort for these standards has provided consistency in the technical content of the standards while ensuring that information developed by CSSP is included.

  18. Analysis of some herbal plants from India used in the control of diabetes mellitus by NAA and AAS techniques

    Energy Technology Data Exchange (ETDEWEB)

    Rajurkar, N.S.; Pardeshi, B.M. [Pune Univ., Chemistry Dept., Pune (India)

    1997-08-01

    Elemental analysis of some herbal plants used in the control of diabetes has been done by the techniques of Neutron Activation Analysis (NAA) and Atomic Absorption Spectroscopy (AAS). The elements Mn, Na, K, Cl, Al, Cu, Co, Pb, Ni, Cr, Cd, Fe, Ca, Zn and Hg are found to be present in different plants in various proportions. (Author).

  19. The technique of sand control with expandable screens

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, P. [Petrochina, Liaohe (China). Liaohe Oilfield Co.

    2009-07-01

    Sand production in heavy oil reservoirs can limit the normal production of oil wells. In this study, expandable screens were used as a sand control mechanism by filtering the sand as it entered the wellbore. The screen systems consists of an expandable outer housing, an expandable base pipe and a filtering layer. The screen expands radially through an expandable cone and presses into the casing well. Axial tension is used to shrink the screens radially through a fishing anchor in order to remove them from the well. The lack of a sand ring between the screen and the casing increases the flow area of the oil and reduces flow resistance caused by fine silt blockages. A series of laboratory experiments were conducted to study the expansion and shrinkage properties of the screens. A field test conducted at a well located in the Liaohe oilfield in China demonstrated that good sand control results can be obtained without the need for pump checking. It was concluded that the sand control method is easy to use and provides good sand control results in large open flow areas. 2 refs., 2 tabs., 3 figs.

  20. Design of a Fractional Order PID Controller Using Particle Swarm Optimization Technique

    CERN Document Server

    Maiti, Deepyaman; Konar, Amit

    2008-01-01

    Particle Swarm Optimization technique offers optimal or suboptimal solution to multidimensional rough objective functions. In this paper, this optimization technique is used for designing fractional order PID controllers that give better performance than their integer order counterparts. Controller synthesis is based on required peak overshoot and rise time specifications. The characteristic equation is minimized to obtain an optimum set of controller parameters. Results show that this design method can effectively tune the parameters of the fractional order controller.

  1. Active Vibration Control of a Monopile Offshore Structure

    DEFF Research Database (Denmark)

    Nielsen, Søren R. K.; Kirkegaard, Poul Henning; Thesbjerg, L.

    1996-01-01

    . This concept has been experimentally investigated with a test model in stationary flow tests. The idea is to have a large drag coefficient when the cylinder moves opposite of the wave direction implying a relatively large damping excitation. When the structure moves in the wave direction a small drag...... with a factor 1.5-2 by blowing air out of the holes in a cylinder vibrating in a stationary water flow....... an active control technique has been proposed in corporation with the consulting company Rambøll, Esbjerg, Denmark. The proposed control technique is based on the relationship between the position of the separation points of the boundary layer flow and the drag term in the wave force on the cylinder...

  2. BWR startup and shutdown activity transport control

    International Nuclear Information System (INIS)

    This paper summarizes BWR industry experience on good practices for controlling the transport of corrosion product activity during shutdowns, particularly refueling outages, and for startup chemistry control to minimize IGSCC (intergranular stress corrosion cracking). For shutdown, overall goals are to minimize adverse impacts of crud bursts and the time required to remove activated corrosion products from the reactor coolant during the shutdown process prior to refueling, and to assist plants in predicting and controlling radiation exposure during outages. For startup, the overall goals are to highlight conditions during early heatup and startup when sources of reactor coolant oxidants are high, when there is a greater likelihood for chemical excursions associated with refueling outage work activities, and when hydrogen injection is not available to mitigate IGSCC due to system design limitations. BWR water chemistry has changed significantly in recent years with the adoption of hydrogen water chemistry, zinc addition and noble metal chemical applications. These processes have, in some instances, resulted in significant activity increases during shutdown evolutions, which together with reduced time for cleanup because of shorter outages, has consequently increased outage radiation exposure. A review several recent outages shows that adverse effects from these conditions can be minimized, leading to the set of good practice recommendations for shutdown chemistry control. Most plants lose the majority of their hydrogen availability hours during early startup because feedwater hydrogen injection systems were not originally designed to inject hydrogen below 20% power. Hydrogen availability has improved through modifications to inject hydrogen at lower power levels, some near 5%. However, data indicate that IGSCC is accelerated during early startup, when dissolved oxygen and hydrogen peroxide levels are high and reactor coolant temperatures are in the 300 to 400 oF (

  3. Active noise control: A tutorial for HVAC designers

    Energy Technology Data Exchange (ETDEWEB)

    Gelin, L.J.

    1997-08-01

    This article will identify the capabilities and limitations of ANC in its application to HVAC noise control. ANC can be used in ducted HVAC systems to cancel ductborne, low-frequency fan noise by injecting sound waves of equal amplitude and opposite phase into an air duct, as close as possible to the source of the unwanted noise. Destructive interference of the fan noise and injected noise results in sound cancellation. The noise problems that it solves are typically described as rumble, roar or throb, all of which are difficult to address using traditional noise control methods. This article will also contrast the use of active against passive noise control techniques. The main differences between the two noise control measures are acoustic performance, energy consumption, and design flexibility. The article will first present the fundamentals and basic physics of ANC. The application to real HVAC systems will follow.

  4. Advanced nonlinear control of three phase series active power filter

    Directory of Open Access Journals (Sweden)

    Abouelmahjoub Y.

    2014-01-01

    Full Text Available The problem of controlling three-phase series active power filter (TPSAPF is addressed in this paper in presence of the perturbations in the voltages of the electrical supply network. The control objective of the TPSAPF is twofold: (i compensation of all voltage perturbations (voltage harmonics, voltage unbalance and voltage sags, (ii regulation of the DC bus voltage of the inverter. A controller formed by two nonlinear regulators is designed, using the Backstepping technique, to provide the above compensation. The regulation of the DC bus voltage of the inverter is ensured by the use of a diode bridge rectifier which its output is in parallel with the DC bus capacitor. The Analysis of controller performances is illustrated by numerical simulation in Matlab/Simulink environment.

  5. The activation of irrigation solutions in Endodontics: a perfected technique

    OpenAIRE

    Michele Simeone; Alessandra Valletta; Amerigo Giudice; Pierpaolo Di Lorenzo; Alfredo Iandolo

    2015-01-01

    Aim: In endodontics a complete chemo mechanical cleansing of the complex root canal system is essential in order to achieve a theraupetic success. Methodology: Sodium hypoclorite due to its antimicrobial and proteolytic characteristic, is an efficient endodontic irrigant and it is the most commonly used. The following article introduces a refined technique in order to increase the degree of cleansing during endodontic treatment. The technique involves intracanal heating of the irriga...

  6. Development of mercury control techniques for utility boilers

    Energy Technology Data Exchange (ETDEWEB)

    Livengood, C.D.; Mendelsohn, M.H.; Huang, H.S.; Wu, J.M.

    1995-06-01

    This paper gives an overview of research being conducted at Argonne National Laboratory on the capture of mercury in flue gas by both dry sorbents and wet scrubbers. The emphasis in the research is on development of a better understanding of the key factors that control the capture of mercury. Future work is expected to utilize that information for the development of new or modified process concepts featuring enhanced mercury capture capabilities.

  7. Wind Erosion Processes and Control Techniques in the Sahelian Zone of Niger

    NARCIS (Netherlands)

    Sterk, G.; Stroosnijder, L.; Raats, P.A.C.

    1999-01-01

    Wind Erosion Processes and Control Techniques in the Sahelian Zone of Niger G. Sterk, L. Stroosnijder, and P.A.C. Raats Abstract The objective of this paper is to present the main results and conclusions from three years of field research on wind erosion processes and control techniques in the Sahel

  8. Successful Application of Active Learning Techniques to Introductory Microbiology.

    Science.gov (United States)

    Hoffman, Elizabeth A.

    2001-01-01

    Points out the low student achievement in microbiology courses and presents an active learning method applied in an introductory microbiology course which features daily quizzes, cooperative learning activities, and group projects. (Contains 30 references.) (YDS)

  9. Active Noise Control in Forest Machines

    OpenAIRE

    Forsgren, Fredrik

    2011-01-01

    Achieving a low noise level is of great interest to the forest machine industry. Traditionally this is obtained by using passive noise reduction, i.e. by using materials for sound isolation and sound absorption. Especially designs to attenuate low frequency noise tend to be bulky and impractical from an installation point of view. An alternative solution to the problem is to use active noise control (ANC). The basic principle of ANC is to generate an anti-noise signal designed to destructivel...

  10. Active noise control for high frequencies

    OpenAIRE

    Kaymak, E; Atherton, MA; Rotter, KRG; Millar, B.

    2006-01-01

    There are many applications that can benefit from Active Noise Control (ANC) such as in aircraft cabins and air conditioning ducts, i.e. in situations where technology interferes with human hearing in a harmful way or disrupts communication. Headsets with analogue ANC circuits have been used in the armed forces for attenuating frequencies below 1 kHz, which when combined with passive filtering offers protection across the whole frequency range of human hearing. A dental surgery is also a nois...

  11. Active Control of Shear Thickening in Suspensions

    CERN Document Server

    Lin, Neil Y C; Cates, Michael E; Sun, Jin; Cohen, Itai

    2016-01-01

    Shear thickening, an increase of viscosity with shear rate, is a ubiquitous phenomena in suspended materials that has implications for broad technological applications. Controlling this thickening behavior remains a major challenge and has led to empirical strategies ranging from altering the particle surfaces and shape to modifying the solvent properties. However, none of these methods allow for active control of flow properties during shear itself. Here, we demonstrate that by strategic imposition of a high-frequency and low-amplitude shear perturbation orthogonal to the primary shearing flow, we can largely eradicate shear thickening. The orthogonal shear effectively becomes a regulator for controlling thickening in the suspension, allowing the viscosity to be reduced by up to two decades on demand. In a separate setup, we show that such effects can be induced by simply agitating the sample transversely to the primary shear direction. Overall, the ability of in situ manipulation of shear thickening paves a...

  12. Low activation brazing materials and techniques for SiC f/SiC composites

    Science.gov (United States)

    Riccardi, B.; Nannetti, C. A.; Petrisor, T.; Sacchetti, M.

    2002-12-01

    A low activation brazing technique for silicon carbide fiber reinforced silicon carbide matrix composites (SiC f/SiC) is presented; this technique is based on the use of the 78Si-22Ti (wt%) eutectic alloy. The joints obtained take advantage of a melting point able to avoid composite fibre-interface degradation. All the joints showed absence of discontinuities and defects at the interface and a fine eutectic structure. Moreover, the joint layer appeared well adherent both to the matrix and the fibre interphase and the brazing alloy infiltration looked sufficiently controlled. The joints of SiC f/SiC composites showed 71±10 MPa almost pure shear strength at RT and up to 70 MPa at 600 °C.

  13. Beaconless adaptive-optics technique for HEL beam control

    Science.gov (United States)

    Khizhnyak, Anatoliy; Markov, Vladimir

    2016-05-01

    Effective performance of forthcoming laser systems capable of power delivery on a distant target requires an adaptive optics system to correct atmospheric perturbations on the laser beam. The turbulence-induced effects are responsible for beam wobbling, wandering, and intensity scintillation, resulting in degradation of the beam quality and power density on the target. Adaptive optics methods are used to compensate for these negative effects. In its turn, operation of the AOS system requires a reference wave that can be generated by the beacon on the target. This report discusses a beaconless approach for wavefront correction with its performance based on the detection of the target-scattered light. Postprocessing of the beacon-generated light field enables retrieval and detailed characterization of the turbulence-perturbed wavefront -data that is essential to control the adaptive optics module of a high-power laser system.

  14. Computed tomography practice in Sweden. Quality control, techniques and patient dose

    International Nuclear Information System (INIS)

    A survey on computed tomography (CT) practice was carried out in Sweden. The items investigated were the examination frequency, the age/sex distribution and the techniques used for all types of examination, including the assessment of patient dose. The radiation doses were analysed and discussed with respect to individual values, to the variation with different techniques and different types of equipment, to the collective impact for the whole country, and to the level of quality control measures applied. Examination statistics and techniques were derived from protocols recorded for every patient examination performed in one week, containing all relevant patient and exposure data. The dose assessment was based on measurements with a pencil-shaped ionisation chamber in cylindrical standard phantoms and free in air. All but one of the 90 CT scanners installed in Sweden at the time of this investigation participated. The examination statistics are similar to those reported from other countries, especially with regard to the age and sex distribution and to the type of examinations. The patient dose was strongly correlated with the type of equipment, was moderated slightly with differences in the choice of exposure settings, and showed no correlation at all with the extent of QC activities. The annual frequency is 24 CT examinations per 1000 inhabitants, leading to a collective effective dose of 840 man.Sv or approximately 0.1 mSv per inhabitant. Examinations of the trunk region give the largest contributions, followed by examinations of the brain and the spine. (Author)

  15. TiO2 photocatalytic antifungal technique for crops diseases control

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    TiO2 and l%Ce3+-TiO2 prepared by hydrothermal method were characterized by means of XRD and UV-visible diffusive reflectance spectra(DRS). The results of DRS analysis indicated that the 1%Ce3+-TiO2 catalyst had significant optical absorption in the visible region between 400-450 nm because electrons could be excited from the valence band of TiO2 or cerium oxides to Ce 4f level. To investigate the photocatalytic activity of different catalysts for crop fungal disease control, a series of Quine tests were carried out for cucumber powdery mildew and litchi downy blight control in home-made photocatalytic reactor. The results showed that TiO2photocatalysis technique should be effective to inhibit the growth of fungal diseases to some extent and P-25 had a higher activity for antifungal control than home-made TiO2 catalysts. TiO2-A prepared with Ti(SO4)2 is more active to contro 1 antifungal disease than TiO2-B prepared with TiOSO4 as precursor because the crystalline of TiO2-A was higher than that of TiO2-B. The antifungal index litchi downy blight control was greatly enhanced by doping 1% cerium ion. The antifungal index of 1.0%Ce3+-TiO2 was(47.0±4.7)%,(82.2 ± 3.5)%, (100± 0.0)% under indoor weaker light, solar light and black light, respectively. The results of field experiments showed that the antifungal index of 1.0%Ce3+-TiO2 was more than that of P-25. The antifungal index of 1.0%Ce3+-TiO2 was (81.7 ±6.5)%, (67.5 ±4.7)%, (38.6 ±1.9)% for litchi downy blight, maize southern leaf spot, and rice blast, respectively. It was concluded that TiO2 photocatalysis technique should be an effective way for litchi fungal disease control in practice.

  16. Local flow control for active building facades

    Science.gov (United States)

    Kaligotla, Srikar; Chen, Wayne; Glauser, Mark

    2010-11-01

    Existing building facade designs are for a passive and an impermeable shell to prevent migration of outdoor air into the building and to control heat transfers between the exterior environment and the building interior. An active facade that can respond in real time to changing environmental conditions like wind speed and direction, pollutant load, temperature, humidity and light can lower energy use and maximize occupant comfort. With an increased awareness of cost and environmental effects of energy use, cross or natural ventilation has become an attractive method to lower energy use. Separated flow regions around such buildings are undesirable due to high concentration of pollutants, especially if the vents or dynamic windows for cross ventilation are situated in these regions. Outside pollutant load redistribution through vents can be regulated via flow separation control to minimize transport of pollutants into the building. Flow separation has been substantially reduced with the application of intelligent flow control tools developed at Syracuse University for flow around "silo" (turret) like structures. Similar flow control models can be introduced into buildings with cross ventilation for local external flow separation control. Initial experiments will be performed for turbulent flow over a rectangular block (scaled to be a mid-rise building) that has been configured with dynamic vents and unsteady suction actuators in a wind tunnel at various wind speeds.

  17. HPLC-MS technique for radiopharmaceuticals research and control

    International Nuclear Information System (INIS)

    A liquid chromatography/refractive index detector/radiometric detector/ mass spectrometric detector combination (Agilent 1100 HPLC/RAD/DAD/RID/MSD system) is used as a complex technique for quality assessment of radiopharmaceuticals such as 2-deoxy-2-[18F]fluoro-D-glucose (FDG). Optimisation of HPLC/MS analysis was performed investigating the electrospray ionisation (ESI) analytical signal of the mass spectrometer as a function of solvent composition. The anion-exchange eluents applied as specified by the pharmacopoeia are not suitable for ESI detection due to high ion concentrations. Therefore, solutions of glucose in methanol/water and acetonitrile/water solutions of various semi-volatile electrolytes (ammonium chloride, formic acid, ammonium formate) were analysed by flow injection analysis (FIA) and chromatographically. The best analytical response was obtained with acetonitrile : 0.25% ammonium formate = 80:20 solutions. The most intense MSD signals of FDG in ammonium formate were obtained for the following complex ions: (i) positive ions: fdg.NH4+, fdg.Na+ and (fdg2-CH3O).Na+ (m/z = 200, 205 and 344); (ii) negative ions: fdg.Cl- and fdg.HCOO- (m/z= 217 and 227). The HPLC-MS analysis with Zorbax C-18 and Asahipak-NH2P50 columns gave evidence of admixtures and radiolytic formation of deoxyglucose, deoxychloro-glucose, erythrose, erythritol, gluconic acid, lactose, raffinose, saccharic acid, sorbitol/[19F]FDG, sorbitol/[19F]FDG, xylitol, and other compounds. However, radiometric analysis of expired samples of [18F]FDG gave evidence of a very high radiation stability of its water-ethanol solutions at the point of output of radioactive products. Remarkable is the exceedingly high complexity of the mass spectra of FDG as compared to glucose. Therefore, further research concerns the influence of sodium chloride, linearity of signal response, impurities (mannitol, mannose etc.) interference, and robustness of the MS analysis, with special attention to the ratio of

  18. Recent developments in the techniques of controlling and measuring suction in unsaturated soils

    OpenAIRE

    Delage, Pierre; Romero, Enrique; Tarantino, Alessandro

    2008-01-01

    The difficulty of measuring and controlling suction in unsaturated soils is one of the reasons why the development of the mechanics of unsaturated soils has not been as advanced as that of saturated soils. However, significant developments have been carried out in the last decade in this regard. In this paper, a re-view of some developments carried out in the techniques of controlling suction by using the axis translation, the osmotic method and the vapour control technique is presented. The ...

  19. AN OVERVIEW OF POWER DISSIPATION AND CONTROL TECHNIQUES IN CMOS TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    N. B. ROMLI

    2015-03-01

    Full Text Available Total power dissipation in CMOS circuits has become a huge challenging in current semiconductor industry due to the leakage current and the leakage power. The exponential growth of both static and dynamic power dissipations in any CMOS process technology option has increased the cost and efficiency of the system. Technology options are used for the execution specifications and usually it depends on the optimisation and the performance constraints over the chip. This article reviews the relevant researches of the source or power dissipation, the mechanism to reduce the dynamic power dissipation as well as static power dissipation and an overview of various circuit techniques to control them. Important device parameters including voltage threshold and switching capacitance impact to the circuit performance in lowering both dynamic and static power dissipation are presented. The demand for the reduction of power dissipation in CMOS technology shall remain a challenging and active area of research for years to come. Thus, this review shall work as a guideline for the researchers who wish to work on power dissipation and control techniques.

  20. Real Time Vibration Control of Active Suspension System with Active Force Control using Iterative Learning Algorithm

    OpenAIRE

    Kalaivani; Lakshmi; Rajeswari

    2013-01-01

    This paper presents concurrent vibration control of a laboratory scaled vibration isolator platform with Active Force Control (AFC) using Iterative Learning Algorithm (ILA). The work investigates the performance of the traditional Proportional Integral Derivative Controller (PIDC) with and without AFC using ILA for vibration suppression. The physical single degree of freedom quarter car has been interfaced with a personal computer using a National Instruments data acquisition card NI USB 6008...

  1. Technique and experiment of active direct gas pressure measurement in coal roadway

    Institute of Scientific and Technical Information of China (English)

    CHEN Xue-xi; MA Shang-quan; QI Li-ming

    2009-01-01

    An active measurement method and its principle was introduced considering the low success rate, special difficulty, and long measurement time of the direct gas pres-sure measurement currently used in coal roadways. The technology of drilling, borehole sealing depth, borehole sealing length, sealing control of the measuring process, com-pensatory computation of gas loss quantity and other key techniques were discussed. Fi-nally, based on the latest instrument the authors developed, a series of experiments of di-rect gas pressure measurement in the coal roadways of the Jincheng and Tongchuan mine district, were carried out. The experimental results show that active gas pressure measurement technique has advantages as follows: (1) the application scope of direct gas pressure measurement technique is wide and it does not have the restriction of coal hardness, coal seam fissure and other conditions; (2) the measured results are credible, which can be tested by the same gas pressure value acquired from a different borehole in the same place; (3) the measurement process is convenient and quick, it takes about 2 to 3 days to acquire the gas pressure value in a coal seam.

  2. The regeneration of polluted activated carbon by radiation techniques

    Energy Technology Data Exchange (ETDEWEB)

    Wu Minghong; Bao Borong [Shanghai Institute of Nuclear Research, Academia Sinica, Shanghai (China); Zhou Ruimin; Zhu Jinliang; Hu Longxin [Shanghai University, Shanghai (China)

    1998-10-01

    In this paper, the regeneration of used activated carbon from monosodium glutamate factory was experimented using radiation and acid-alkali chemical cleaning method. Results showed that the activated carbon saturated with pollutants can be wash away easily by flushing with chemical solution prior irradiation. DSC was used to monitor the change of carbon adsorption.

  3. Active optics control development at the LBT

    Science.gov (United States)

    Ashby, David S.; Biddick, Christopher; Hill, John M.

    2014-07-01

    The Large Binocular Telescope (LBT) is built around two 8.4 m-diameter primary mirrors placed with a centerline separation of 14.4 m in a common altitude/azimuth mount. Each side of the telescope can utilize a deployable prime focus instrument; alternatively, the beam can be directed to a Gregorian instrument by utilizing a deployable secondary mirror. The direct-Gregorian beam can be intercepted and redirected to several bent-Gregorian instruments by utilizing a deployable tertiary mirror. Two of the available bent-Gregorian instruments are interferometers, capable of coherently combining the beams from the two sides of the telescope. Active optics can utilize as many as 26 linearly independent degrees of freedom to position the primary, secondary and tertiary mirrors to control optical collimation while the telescope operates in its numerous observing modes. Additionally, by applying differential forces at 160 locations on each primary mirror, active optics controls the primary mirror figure. The authors explore the challenges associated with collimation and primary mirror figure control at the LBT and outline the ongoing related development aimed at optimizing image quality and preparing the telescope for interferometric operations.

  4. Speed control of PMSM system using improved reaching law based sliding mode control and disturbance observer technique

    Directory of Open Access Journals (Sweden)

    Shital M.Wasu

    2013-12-01

    Full Text Available In this paper, improvement of transient response of the permanent-magnet synchronous motor (PMSM subjected to different level of load disturbances and parametric uncertainties and unmodeled dynamics are studied using improved reaching law sliding mode control (IRLSMC and disturbance observer techniques. Proposed scheme is tested under different load conditions and parametric uncertainties. The results of proposed reaching law are compared with other techniques to prove the effectiveness of proposed scheme. Simulation results show the efficacy of proposed control approach.

  5. Application of thermal analysis techniques in activated carbon production

    Science.gov (United States)

    Donnals, G.L.; DeBarr, J.A.; Rostam-Abadi, M.; Lizzio, A.A.; Brady, T.A.

    1996-01-01

    Thermal analysis techniques have been used at the ISGS as an aid in the development and characterization of carbon adsorbents. Promising adsorbents from fly ash, tires, and Illinois coals have been produced for various applications. Process conditions determined in the preparation of gram quantities of carbons were used as guides in the preparation of larger samples. TG techniques developed to characterize the carbon adsorbents included the measurement of the kinetics of SO2 adsorption, the performance of rapid proximate analyses, and the determination of equilibrium methane adsorption capacities. Thermal regeneration of carbons was assessed by TG to predict the life cycle of carbon adsorbents in different applications. TPD was used to determine the nature of surface functional groups and their effect on a carbon's adsorption properties.

  6. Quality Assurance and Control in Laboratory using Neutron Activation Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Y. S.; Moon, J. H.; Sun, G. M.; Kim, S. H.; Baek, S. Y.; Lim, J. M.; Kim, H. R

    2007-01-15

    In accordance with the increment of international trade associated with the worldwide globalization, the importance of quality assurance and control for the commodity produced from one's own country has been stressed. ISO (International Organization for Standards) defines quality control as 'the operational techniques and activities that are used to fulfill the requirements for quality'. Since 1996, the HANARO research reactor in the Korea Atomic Energy Research Institute has been operated thereafter initial critical operation on April 1995. Neutron activation analysis system and applied techniques which is one of a nuclear analytical technologies using reactor neutrons has been developed for user's supporting and the establishment of the quality system for a measurement and analysis, testing and inspection was implemented successfully. On the basis of the qualified NAA system, the test and measurement of more than 1500 samples which is requested from 30 organizations including industrial companies, universities and institutes carried out in NAA laboratory annually. Moreover, as the goal of mutual recognition agreement (MRA) which can be removed a technical barrier in international trade, the objectivity and the confidence of analytical quality in NAA laboratory became established through the installation of international accreditation system by implementing analytical quality system in accordance with international standards in 2001. The aim of the report was to summarize the technical management of introduction, methods and the results for a quality control and assurance which should be performed in NAA technique using the HANARO research reactor. The report will help building up effective quality control strategy in the future.

  7. Mathematical analysis techniques for modeling the space network activities

    Science.gov (United States)

    Foster, Lisa M.

    1992-01-01

    The objective of the present work was to explore and identify mathematical analysis techniques, and in particular, the use of linear programming. This topic was then applied to the Tracking and Data Relay Satellite System (TDRSS) in order to understand the space network better. Finally, a small scale version of the system was modeled, variables were identified, data was gathered, and comparisons were made between actual and theoretical data.

  8. Residual matrix from different separation techniques impacts exosome biological activity

    OpenAIRE

    Lucia Paolini; Andrea Zendrini; Giuseppe Di Noto; Sara Busatto; Elisabetta Lottini; Annalisa Radeghieri; Alessandra Dossi; Andrea Caneschi; Doris Ricotta; Paolo Bergese

    2016-01-01

    Exosomes are gaining a prominent role in research due to their intriguing biology and several therapeutic opportunities. However, their accurate purification from body fluids and detailed physicochemical characterization remain open issues. We isolated exosomes from serum of patients with Multiple Myeloma by four of the most popular purification methods and assessed the presence of residual contaminants in the preparations through an ad hoc combination of biochemical and biophysical technique...

  9. Active control of multi-input hydraulic journal bearing system

    Science.gov (United States)

    Chuang, Jen-Chen; Chen, Chi-Yin; Tu, Jia-Ying

    2016-09-01

    Because of the advantages of high accuracy, high capacity, and low friction, the development of hydrostatic bearing for machine tool receives significant attention in the last decades. The mechanics and mechanical design of hydrostatic journal bearing with capillary restrictors has been discussed in literature. However, pragmatically, the undesired loading effects of cutting force tend to result in resonance and instability of the rotor and damage the shaft during operation. Therefore, multi-input, active flow control using state feedback design is proposed in this paper. To this purpose, the proportional pressure valves are added to the hydraulic system as active control devices, and the linearised models of the bearing and valve are discussed and identified. Simulation and experimental work is conducted to verify the proposed active control and parameter identification techniques. The results show that the unbalance responses of the rotor are reduced by the proposed state feedback controller, which is able to regulate the flow pressure effectively, thus enhancing the stability and accuracy of the hydraulic journal bearing.

  10. Creation of reversed phase high-performance liquid chromatographic technique to assay platelet-activating factor

    Institute of Scientific and Technical Information of China (English)

    杨云梅; 曹红翠; 徐哲荣; 陈晓明

    2004-01-01

    Objective: To establish a new assay for platelet-activating factor (PAF), to compare it with bio-assay; and to discuss its significance in some elderly people diseases such as cerebral infarction and coronary heart disease. Methods: To measure PAF levels in 100 controls, 23 elderly patients with cerebral infarction and 65 cases with coronary heart disease by reversed phase high-performance liquid chromatographic technique (rHPLC). Results:rHPLC is more convenient, sensitive,specific, and less confusing, compared with bio-assay. The level of plasma PAF in patients with cerebral infarction was higher than that in the controls (P<0.01), and in patients with coronary heart disease. Conclusion: Detection of PAF with rHPLC is more reliable and more accurate. The new assay has important significance in PAF research.

  11. Creation of reversed phase high-performance liquid chromatographic technique to assay platelet-activating factor

    Institute of Scientific and Technical Information of China (English)

    杨云梅; 曹红翠; 徐哲荣; 陈晓明

    2004-01-01

    Objective: To establish a new assay for platelet-activating factor (PAF), to compare it with bio-assay; and to discuss its significance in some elderly people diseases such as cerebral infarction and coronary heart disease. Methods: To measure PAF levels in 100 controls, 23 elderly patients with cerebral infarction and 65 cases with coronary heart disease by reversed phase high-performance liquid chromatographic technique (rHPLC). Results: rHPLC is more convenient, sensitive, specific, and less confusing, compared with bio-assay. The level of plasma PAF in patients with cerebral infarction was higher than that in the controls (P<0.01), and in patients with coronary heart disease. Conclusion: Detection of PAF with rHPLC is more reliable and more accurate. The new assay has important significance in PAF research.

  12. Coordinated Voltage Control of Active Distribution Network

    Directory of Open Access Journals (Sweden)

    Xie Jiang

    2016-01-01

    Full Text Available This paper presents a centralized coordinated voltage control method for active distribution network to solve off-limit problem of voltage after incorporation of distributed generation (DG. The proposed method consists of two parts, it coordinated primal-dual interior point method-based voltage regulation schemes of DG reactive powers and capacitors with centralized on-load tap changer (OLTC controlling method which utilizes system’s maximum and minimum voltages, to improve the qualified rate of voltage and reduce the operation numbers of OLTC. The proposed coordination has considered the cost of capacitors. The method is tested using a radial edited IEEE-33 nodes distribution network which is modelled using MATLAB.

  13. Controller modification applied for active fault detection

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Stoustrup, Jakob; Poulsen, Niels Kjølstad

    2014-01-01

    This paper is focusing on active fault detection (AFD) for parametric faults in closed-loop systems. This auxiliary input applied for the fault detection will also disturb the external output and consequently reduce the performance of the controller. Therefore, only small auxiliary inputs are used...... the feedback controller with a minor effect on the external output in the fault free case. Further, in the faulty case, the signature of the auxiliary input can be optimized. This is obtained by using a band-pass filter for the YJBK parameter that is only effective in a small frequency range where...... the frequency for the auxiliary input is selected. This gives that it is possible to apply an auxiliary input with a reduced amplitude. An example is included to show the results....

  14. Actively-controlled Beds for Ambulances

    Institute of Scientific and Technical Information of China (English)

    Takahiko Ono; Hikaru Inooka

    2009-01-01

    During transportation by ambulance,a patient is exposed to inertial acceleration when an ambulance decelerates or turns a corner.Such acceleration often gives a patient physical stress such as blood pressure variation or body sway,which causes strong pain,feeling of discomfort or sometimes critical damage for seriously injured persons.To reduce this undesirable effect of the acceleration,the authors developed the actively-controlled bed (ACB) which controls the posture of a stretcher in real time to reduce foot-to-head and lateral acceleration acting on a supine person.This paper describes development of the ACB,including control system design and performance evaluation.The control system is designed by Zakian's framework,which comprises the principle of matching and the method of inequalities,so that the design specifications on the tracking error and the motor torque are satisfied.From the results of driving experiments and simulation,it is estimated that the ACB can reduce the acceleration acting on a patient by 65% in the foot-to-head direction and by 75% in the lateral direction.

  15. Active control of large space structures: An introduction and overview

    Science.gov (United States)

    Doane, G. B., III; Tollison, D. K.; Waites, H. B.

    1985-01-01

    An overview of the large space structure (LSS) control system design problem is presented. The LSS is defined as a class of system, and LSS modeling techniques are discussed. Model truncation, control system objectives, current control law design techniques, and particular problem areas are discussed.

  16. Active Displacement Control of Active Magnetic Bearing System

    Directory of Open Access Journals (Sweden)

    Kertész Milan

    2014-12-01

    Full Text Available The worldwide energy production nowadays is over 3400 GW while storage systems have a capacity of only 90 GW [1]. There is a good solution for additional storage capacity in flywheel energy storage systems (FES. The main advantage of FES is its relatively high efficiency especially with using the active magnetic bearing system. Therefore there exist good reasons for appropriate simulations and for creating a suitable magneto-structural control system. The magnetic bearing, including actuation, is simulated in the ANSYS parametric design language (APDL. APDL is used to create the loops of transient simulations where boundary conditions (BC are updated based upon a “gap sensor” which controls the nodal position values of the centroid of the shaft and the current density inputs onto the copper windings.

  17. Active noise control technology. Active soon seigyo gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Eguchi, M.; Kokubo, F.; Tanaka, S.; Yao, K. (Sharp Corp., Osaka (Japan))

    1994-05-10

    The signal processing method of the Active Noise Control (ANC) system was studied. The principle of ANC is to output secondary sound waves having opposite phase, identical amplitude from the control point of the sound wave of the primary sound source, and eliminate the noise by interference. As application fields, there are air conditioner ducts and compressors as one dimensional noise source, and automobile and axial fan as three dimensional noise source. In order to improve the stability of coefficient renewal algorithm of Adaptive Digital Filter (ADF), for generation of opposite phase noise, DC-LMS algorithm which can control the rise in gain of specified frequency zone was proposed. Furthermore, with the purpose of reducing the amount of operation, the introduction of lattice type AR filter was tested for the stability of the filter in IIR-ADF (Infinite Impulse Response Adaptive Digital Filter) and its application process. The applicability studies of these improved methods on the noise inside of ducts were actually measured, and the effect was verified. For the multi-channel control of 3 dimensional noise source, reference scanning method to reduce the filter operation was proposed. In the partial space noise eliminating experiment, it was made clear that it possesses equivalent effect to error scanning method. 11 refs., 14 figs., 1 tab.

  18. Studies of human dynamic space orientation using techniques of control theory

    Science.gov (United States)

    Young, L. R.

    1974-01-01

    Studies of human orientation and manual control in high order systems are summarized. Data cover techniques for measuring and altering orientation perception, role of non-visual motion sensors, particularly the vestibular and tactile sensors, use of motion cues in closed loop control of simple stable and unstable systems, and advanced computer controlled display systems.

  19. Cell-level battery charge/discharge protection system. [electronic control techniques

    Science.gov (United States)

    Donovan, R. L.; Imamura, M. S.

    1977-01-01

    The paper describes three design approaches to individual cell monitoring and control for sealed secondary battery cells. One technique involves a modular strap-on single cell protector which contains all the electronics required for monitoring cell voltage, responding to external commands, and forming a bypass circuit for the cell. A second technique, the multiplexed cell protector, uses common circuitry to monitor and control each cell in a battery pack. The third technique, the computerized cell protector, by replacing the hard-wired logic of the multiplexed cell protector with a microprocessor, achieves greatest control flexibility and inherent computational capability with a minimum parts count implementation.

  20. 基于滑模控制的谐振阻抗型混合有源滤波系统控制技术%Control Technique of the Resonant Impedance Type Hybrid Active Power Filter Based on Sliding Mode Control

    Institute of Scientific and Technical Information of China (English)

    梁应昌

    2015-01-01

    基于滑模控制原理,针对矿用谐振阻抗型混合有源滤波系统( RITHAPF)控制技术进行深入研究,并对电网进行无功补偿和谐波抑制。利用开关函数建模法进行系统建模,给出RITHAPF的数学模型。通过对RITHAPF的等效模型的分析推导,提出了RITHAPF系统的收敛和稳定判据。结合离散指数趋近律对离散滑模控制的影响,将连续系统的指数趋近律方法推广到离散系统,证明离散指数趋近律滑模控制对系统摄动和外界干扰依然具有鲁棒性。进一步根据有源电力滤波器的离散数学模型,设计滑模离散数学模型。基于趋近律离散滑模变结构控制设计有源部分的电流跟踪控制器。结果表明,采用滑模控制的谐振阻抗型混合有源滤波器对矿用直流提升系统6 kV母线的无功功率和谐波电流补偿效果良好。%Based on principle of sliding mode control,the mine-used resonant impedance type hybrid active power filter system ( RITHAPF) control technology was further researched,and reactive power compensation and harmonic suppression on power grid were made. The switching function modeling method was adopted to make modeling and propose the mathematical model of RITHAPF. Through the derivation of RITHAPF equivalent model,a convergence and stability criterion was put for-ward for RITHAPF system. Combining the influence of discrete index reaching law on discrete sliding mode control,the reac-hing law index of the continuous system was extended to the discrete system,to prove that influence of the discrete index on the system perturbations and external disturbances is still robust. Furthermore,according to the discrete mathematical model of ac-tive power filter,the synovial discrete mathematical model is given. The active part current tracking controller was designed based on the reaching law of the discrete sliding mode control. The simulation results showed that the resonant impedance type

  1. Real Time Vibration Control of Active Suspension System with Active Force Control using Iterative Learning Algorithm

    Directory of Open Access Journals (Sweden)

    Kalaivani

    2013-09-01

    Full Text Available This paper presents concurrent vibration control of a laboratory scaled vibration isolator platform with Active Force Control (AFC using Iterative Learning Algorithm (ILA. The work investigates the performance of the traditional Proportional Integral Derivative Controller (PIDC with and without AFC using ILA for vibration suppression. The physical single degree of freedom quarter car has been interfaced with a personal computer using a National Instruments data acquisition card NI USB 6008. The controllers are designed and simulated using LabVIEW simulation software. The results infer that the PIDC with AFC using ILA works superior than the PIDC.

  2. Wind turbine generators with active radar signature control blades

    Science.gov (United States)

    Tennant, Alan; Chambers, Barry

    2004-07-01

    The large radar cross section of wind turbine generator (WTG) blades combined with high tip speeds can produce significant Doppler returns when illuminated by a radar. Normally, an air traffic control radar system will filter out large returns from stationary targets, however the Doppler shifts introduced by the WTG are interpreted as moving aircraft that can confuse radar operators and compromise safety. A possible solution to this problem that we are investigating is to incorporate an active layer into the structure of the WTG blades that can be used to dynamically modulate the RCS of the blade return. The active blade can operate in one of two modes: firstly the blade RCS can be modulated to provide a Doppler return that is outside the detectable range of the radar receiver system so that it is rejected: a second mode of operation is to introduce specific coding on to the Doppler returns so that they may be uniquely identified and rejected. The active layer used in the system consists of a frequency selective surface controlled by semiconductor diodes and is a development of techniques that we have developed for active radar absorbers. Results of experimental work using a 10GHz Doppler radar and scale model WTG with active Doppler imparting blades are presented.

  3. High-speed reference-beam-angle control technique for holographic memory drive

    Science.gov (United States)

    Yamada, Ken-ichiro; Ogata, Takeshi; Hosaka, Makoto; Fujita, Koji; Okuyama, Atsushi

    2016-09-01

    We developed a holographic memory drive for next-generation optical memory. In this study, we present the key technology for achieving a high-speed transfer rate for reproduction, that is, a high-speed control technique for the reference beam angle. In reproduction in a holographic memory drive, there is the issue that the optimum reference beam angle during reproduction varies owing to distortion of the medium. The distortion is caused by, for example, temperature variation, beam irradiation, and moisture absorption. Therefore, a reference-beam-angle control technique to position the reference beam at the optimum angle is crucial. We developed a new optical system that generates an angle-error-signal to detect the optimum reference beam angle. To achieve the high-speed control technique using the new optical system, we developed a new control technique called adaptive final-state control (AFSC) that adds a second control input to the first one derived from conventional final-state control (FSC) at the time of angle-error-signal detection. We established an actual experimental system employing AFSC to achieve moving control between each page (Page Seek) within 300 µs. In sequential multiple Page Seeks, we were able to realize positioning to the optimum angles of the reference beam that maximize the diffracted beam intensity. We expect that applying the new control technique to the holographic memory drive will enable a giga-bit/s-class transfer rate.

  4. Fuzzy Controller Design Using Evolutionary Techniques for Twin Rotor MIMO System: A Comparative Study

    Directory of Open Access Journals (Sweden)

    H. A. Hashim

    2015-01-01

    Full Text Available This paper presents a comparative study of fuzzy controller design for the twin rotor multi-input multioutput (MIMO system (TRMS considering most promising evolutionary techniques. These are gravitational search algorithm (GSA, particle swarm optimization (PSO, artificial bee colony (ABC, and differential evolution (DE. In this study, the gains of four fuzzy proportional derivative (PD controllers for TRMS have been optimized using the considered techniques. The optimization techniques are developed to identify the optimal control parameters for system stability enhancement, to cancel high nonlinearities in the model, to reduce the coupling effect, and to drive TRMS pitch and yaw angles into the desired tracking trajectory efficiently and accurately. The most effective technique in terms of system response due to different disturbances has been investigated. In this work, it is observed that GSA is the most effective technique in terms of solution quality and convergence speed.

  5. Fuzzy Controller Design Using Evolutionary Techniques for Twin Rotor MIMO System: A Comparative Study.

    Science.gov (United States)

    Hashim, H A; Abido, M A

    2015-01-01

    This paper presents a comparative study of fuzzy controller design for the twin rotor multi-input multioutput (MIMO) system (TRMS) considering most promising evolutionary techniques. These are gravitational search algorithm (GSA), particle swarm optimization (PSO), artificial bee colony (ABC), and differential evolution (DE). In this study, the gains of four fuzzy proportional derivative (PD) controllers for TRMS have been optimized using the considered techniques. The optimization techniques are developed to identify the optimal control parameters for system stability enhancement, to cancel high nonlinearities in the model, to reduce the coupling effect, and to drive TRMS pitch and yaw angles into the desired tracking trajectory efficiently and accurately. The most effective technique in terms of system response due to different disturbances has been investigated. In this work, it is observed that GSA is the most effective technique in terms of solution quality and convergence speed. PMID:25960738

  6. Relations Between Autonomous Motivation and Leisure-Time Physical Activity Participation: The Mediating Role of Self-Regulation Techniques.

    Science.gov (United States)

    Nurmi, Johanna; Hagger, Martin S; Haukkala, Ari; Araújo-Soares, Vera; Hankonen, Nelli

    2016-04-01

    This study tested the predictive validity of a multitheory process model in which the effect of autonomous motivation from self-determination theory on physical activity participation is mediated by the adoption of self-regulatory techniques based on control theory. Finnish adolescents (N = 411, aged 17-19) completed a prospective survey including validated measures of the predictors and physical activity, at baseline and after one month (N = 177). A subsample used an accelerometer to objectively measure physical activity and further validate the physical activity self-report assessment tool (n = 44). Autonomous motivation statistically significantly predicted action planning, coping planning, and self-monitoring. Coping planning and self-monitoring mediated the effect of autonomous motivation on physical activity, although self-monitoring was the most prominent. Controlled motivation had no effect on self-regulation techniques or physical activity. Developing interventions that support autonomous motivation for physical activity may foster increased engagement in self-regulation techniques and positively affect physical activity behavior. PMID:27390147

  7. Self-controllable Voltage Level Technique to reduce leakage current in DRAM 4×4

    OpenAIRE

    Radha K; M. Sowmyasri

    2016-01-01

    As the technology improved to support very large chip sizes, system designers were faced with power consumption problem and leakage current problem. CMOS technology has increased in level of importance to the point where it now clearly holds center stage as the dominant VLSI technology The present work shows the implementation of a DRAM 4×4 (dynamic random access memory) with self controllable voltage level (SVL) technique. SVL technique is leakage current reduction technique. Sim...

  8. Technical management techniques for identification and control of industrial safety and pollution hazards

    Science.gov (United States)

    Campbell, R.; Dyer, M. K.; Hoard, E. G.; Little, D. G.; Taylor, A. C.

    1972-01-01

    Constructive recommendations are suggested for pollution problems from offshore energy resources industries on outer continental shelf. Technical management techniques for pollution identification and control offer possible applications to space engineering and management.

  9. Techniques for active embodiment of participants in virtual environments

    Energy Technology Data Exchange (ETDEWEB)

    Hightower, R.; Stansfield, S.

    1996-03-01

    This paper presents preliminary work in the development of an avatar driver. An avatar is the graphical embodiment of a user in a virtual world. In applications such as small team, close quarters training and mission planning and rehearsal, it is important that the user`s avatar reproduce his or her motions naturally and with high fidelity. This paper presents a set of special purpose algorithms for driving the motion of the avatar with minimal information about the posture and position of the user. These algorithms utilize information about natural human motion and posture to produce solutions quickly and accurately without the need for complex general-purpose kinematics algorithms. Several examples illustrating the successful applications of these techniques are included.

  10. Optimizaton of corrosion control for lead in drinking water using computational modeling techniques

    Science.gov (United States)

    Computational modeling techniques have been used to very good effect in the UK in the optimization of corrosion control for lead in drinking water. A “proof-of-concept” project with three US/CA case studies sought to demonstrate that such techniques could work equally well in the...

  11. Application of a sensitivity analysis technique to high-order digital flight control systems

    Science.gov (United States)

    Paduano, James D.; Downing, David R.

    1987-01-01

    A sensitivity analysis technique for multiloop flight control systems is studied. This technique uses the scaled singular values of the return difference matrix as a measure of the relative stability of a control system. It then uses the gradients of these singular values with respect to system and controller parameters to judge sensitivity. The sensitivity analysis technique is first reviewed; then it is extended to include digital systems, through the derivation of singular-value gradient equations. Gradients with respect to parameters which do not appear explicitly as control-system matrix elements are also derived, so that high-order systems can be studied. A complete review of the integrated technique is given by way of a simple example: the inverted pendulum problem. The technique is then demonstrated on the X-29 control laws. Results show linear models of real systems can be analyzed by this sensitivity technique, if it is applied with care. A computer program called SVA was written to accomplish the singular-value sensitivity analysis techniques. Thus computational methods and considerations form an integral part of many of the discussions. A user's guide to the program is included. The SVA is a fully public domain program, running on the NASA/Dryden Elxsi computer.

  12. Control of the olive fruit fly using genetics-enhanced sterile insect technique

    OpenAIRE

    Ant Thomas; Koukidou Martha; Rempoulakis Polychronis; Gong Hong-Fei; Economopoulos Aris; Vontas John; Alphey Luke

    2012-01-01

    Abstract Background The olive fruit fly, Bactrocera oleae, is the major arthropod pest of commercial olive production, causing extensive damage to olive crops worldwide. Current control techniques rely on spraying of chemical insecticides. The sterile insect technique (SIT) presents an alternative, environmentally friendly and species-specific method of population control. Although SIT has been very successful against other tephritid pests, previous SIT trials on olive fly have produced disap...

  13. Control of the olive fruit fly using genetics-enhanced sterile insect technique

    Directory of Open Access Journals (Sweden)

    Ant Thomas

    2012-06-01

    Full Text Available Abstract Background The olive fruit fly, Bactrocera oleae, is the major arthropod pest of commercial olive production, causing extensive damage to olive crops worldwide. Current control techniques rely on spraying of chemical insecticides. The sterile insect technique (SIT presents an alternative, environmentally friendly and species-specific method of population control. Although SIT has been very successful against other tephritid pests, previous SIT trials on olive fly have produced disappointing results. Key problems included altered diurnal mating rhythms of the laboratory-reared insects, resulting in asynchronous mating activity between the wild and released sterile populations, and low competitiveness of the radiation-sterilised mass-reared flies. Consequently, the production of competitive, male-only release cohorts is considered an essential prerequisite for successful olive fly SIT. Results We developed a set of conditional female-lethal strains of olive fly (named Release of Insects carrying a Dominant Lethal; RIDL®, providing highly penetrant female-specific lethality, dominant fluorescent marking, and genetic sterility. We found that males of the lead strain, OX3097D-Bol, 1 are strongly sexually competitive with wild olive flies, 2 display synchronous mating activity with wild females, and 3 induce appropriate refractoriness to wild female re-mating. Furthermore, we showed, through a large proof-of-principle experiment, that weekly releases of OX3097D-Bol males into stable populations of caged wild-type olive fly could cause rapid population collapse and eventual eradication. Conclusions The observed mating characteristics strongly suggest that an approach based on the release of OX3097D-Bol males will overcome the key difficulties encountered in previous olive fly SIT attempts. Although field confirmation is required, the proof-of-principle suppression and elimination of caged wild-type olive fly populations through OX3097D

  14. Temperature Control of Gas Chromatograph Based on Switched Delayed System Techniques

    OpenAIRE

    Xiao-Liang Wang; Ming-Xu Zhang; Kun-Zhi Liu; Xi-Ming Sun

    2014-01-01

    We address the temperature control problem of the gas chromatograph. We model the temperature control system of the gas chromatograph into a switched delayed system and analyze the stability by common Lyapunov functional technique. The PI controller parameters can be given based on the proposed linear matrix inequalities (LMIs) condition and the designed controller can make the temperature of gas chromatograph track the reference signal asymptotically. An experiment is given to illustrate the...

  15. Temperature Control of Gas Chromatograph Based on Switched Delayed System Techniques

    Directory of Open Access Journals (Sweden)

    Xiao-Liang Wang

    2014-01-01

    Full Text Available We address the temperature control problem of the gas chromatograph. We model the temperature control system of the gas chromatograph into a switched delayed system and analyze the stability by common Lyapunov functional technique. The PI controller parameters can be given based on the proposed linear matrix inequalities (LMIs condition and the designed controller can make the temperature of gas chromatograph track the reference signal asymptotically. An experiment is given to illustrate the effectiveness of the stability criterion.

  16. The application of emulation techniques in the analysis of highly reliable, guidance and control computer systems

    Science.gov (United States)

    Migneault, Gerard E.

    1987-01-01

    Emulation techniques can be a solution to a difficulty that arises in the analysis of the reliability of guidance and control computer systems for future commercial aircraft. Described here is the difficulty, the lack of credibility of reliability estimates obtained by analytical modeling techniques. The difficulty is an unavoidable consequence of the following: (1) a reliability requirement so demanding as to make system evaluation by use testing infeasible; (2) a complex system design technique, fault tolerance; (3) system reliability dominated by errors due to flaws in the system definition; and (4) elaborate analytical modeling techniques whose precision outputs are quite sensitive to errors of approximation in their input data. Use of emulation techniques for pseudo-testing systems to evaluate bounds on the parameter values needed for the analytical techniques is then discussed. Finally several examples of the application of emulation techniques are described.

  17. Experimental Comparison of two Active Vibration Control Approaches: Velocity Feedback and Negative Capacitance Shunt Damping

    Science.gov (United States)

    Beck, Benjamin; Schiller, Noah

    2013-01-01

    This paper outlines a direct, experimental comparison between two established active vibration control techniques. Active vibration control methods, many of which rely upon piezoelectric patches as actuators and/or sensors, have been widely studied, showing many advantages over passive techniques. However, few direct comparisons between different active vibration control methods have been made to determine the performance benefit of one method over another. For the comparison here, the first control method, velocity feedback, is implemented using four accelerometers that act as sensors along with an analog control circuit which drives a piezoelectric actuator. The second method, negative capacitance shunt damping, consists of a basic analog circuit which utilizes a single piezoelectric patch as both a sensor and actuator. Both of these control methods are implemented individually using the same piezoelectric actuator attached to a clamped Plexiglas window. To assess the performance of each control method, the spatially averaged velocity of the window is compared to an uncontrolled response.

  18. Successful Application of Active Learning Techniques to Introductory Microbiology

    Directory of Open Access Journals (Sweden)

    Elizabeth A. Hoffman

    2009-12-01

    Full Text Available While the traditional lecture format may be a successful way to teach microbiology to both medical and nursing students, it was not an effective means of learning for many prenursing and preprofessional students enrolled in either of the introductory microbiology courses at Ashland Community College, an open enrollment institution. The structure of both Medical Microbiology and Principles of Microbiology was redesigned to allow students to address the material in an active manner. Daily quizzes, student group discussions, scrapbooks, lab project presentations and papers, and extra credit projects were all added in order to allow students maximum exposure to the course material in a manner compatible with various methods of learning. Student knowledge, course evaluations, and student success rates have all improved with the active learning format.

  19. Hybrid Active Noise Control using Adjoint LMS Algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Hyun Do; Hong, Sik Ki [Dankook University (Korea, Republic of)

    1998-07-01

    A multi-channel hybrid active noise control(MCHANC) is derived by combining hybrid active noise control techniques and adjoint LMS algorithms, and this algorithm is applied to an active noise control system in a three dimensional enclosure. A MCHANC system uses feed forward and feedback filters simultaneously to cancel noises in an enclosure. The adjoint LMs algorithm, in which the error is filtered through an adjoint filter of the secondary channel, is also used to reduce the computational burden of adaptive filters. The overall attenuation performance and convergence characteristics of MCHANC algorithm is better than both multiple-channel feed forward algorithms and multiple-channel feedback algorithms. In a large enclosure, the acoustic reverberation can be very long, which means a very high order feed forward filter must be used to cancel the reverberation noises. Strong reverberation noises are generally narrow band and low frequency, which can be effectively predicted and canceled by a feedback adaptive filters. So lower order feed forward filter taps can be used in MCHANC algorithm which combines advantages of fast convergence and small excess mean square error. In this paper, computer simulations and real time implementations is carried out on a TMS320C31 processor to evaluate the performance of the MCHANC systems. (author). 11 refs., 11 figs., 1 tab.

  20. Figure Analysis: A Teaching Technique to Promote Visual Literacy and Active Learning

    Science.gov (United States)

    Wiles, Amy M.

    2016-01-01

    Learning often improves when active learning techniques are used in place of traditional lectures. For many of these techniques, however, students are expected to apply concepts that they have already grasped. A challenge, therefore, is how to incorporate active learning into the classroom of courses with heavy content, such as molecular-based…

  1. New trends in the development of "active correlations" technique

    Science.gov (United States)

    Tsyganov, Yu. S.

    2016-09-01

    With reaching extremely high intensities of heavy-ion beams, new requirements for the detection system of the Dubna Gas-Filled Recoil Separator (DGFRS) will definitely be set. One of the challenges is how to apply the "active correlations" method [1-6] to suppress beam associated background products without significant losses in the whole long-term experiment efficiency value. Different scenarios and equations for the development of a method according to this requirement are under consideration in the present paper.

  2. Instrumental Neutron Activation Analysis Technique using Subsecond Radionuclides

    DEFF Research Database (Denmark)

    Nielsen, H.K.; Schmidt, J.O.

    1987-01-01

    The fast irradiation facility Mach-1 installed at the Danish DR 3 reactor has been used in boron determinations by means of Instrumental Neutron Activation Analysis using12B with 20-ms half-life. The performance characteristics of the system are presented and boron determinations of NBS standard...... reference materials as well as fertilizer materials are compared by literature value and spectrophotometric measurements, respectively. In both cases good agreement is obtained....

  3. Aerial monitoring in active mud volcano by UAV technique

    Science.gov (United States)

    Pisciotta, Antonino; Capasso, Giorgio; Madonia, Paolo

    2016-04-01

    UAV photogrammetry opens various new applications in the close range domain, combining aerial and terrestrial photogrammetry, but also introduces low-cost alternatives to the classical manned aerial photogrammetry. Between 2014 and 2015 tree aerial surveys have been carried out. Using a quadrotor drone, equipped with a compact camera, it was possible to generate high resolution elevation models and orthoimages of The "Salinelle", an active mud volcanoes area, located in territory of Paternò (South Italy). The main risks are related to the damages produced by paroxysmal events. Mud volcanoes show different cyclic phases of activity, including catastrophic events and periods of relative quiescence characterized by moderate activity. Ejected materials often are a mud slurry of fine solids suspended in liquids which may include water and hydrocarbon fluids, the bulk of released gases are carbon dioxide, with some methane and nitrogen, usually pond-shaped of variable dimension (from centimeters to meters in diameter). The scope of the presented work is the performance evaluation of a UAV system that was built to rapidly and autonomously acquire mobile three-dimensional (3D) mapping data in a volcanic monitoring scenario.

  4. Energy management and control of active distribution systems

    Science.gov (United States)

    Shariatzadeh, Farshid

    Advancements in the communication, control, computation and information technologies have driven the transition to the next generation active power distribution systems. Novel control techniques and management strategies are required to achieve the efficient, economic and reliable grid. The focus of this work is energy management and control of active distribution systems (ADS) with integrated renewable energy sources (RESs) and demand response (DR). Here, ADS mean automated distribution system with remotely operated controllers and distributed energy resources (DERs). DER as active part of the next generation future distribution system includes: distributed generations (DGs), RESs, energy storage system (ESS), plug-in hybrid electric vehicles (PHEV) and DR. Integration of DR and RESs into ADS is critical to realize the vision of sustainability. The objective of this dissertation is the development of management architecture to control and operate ADS in the presence of DR and RES. One of the most challenging issues for operating ADS is the inherent uncertainty of DR and RES as well as conflicting objective of DER and electric utilities. ADS can consist of different layers such as system layer and building layer and coordination between these layers is essential. In order to address these challenges, multi-layer energy management and control architecture is proposed with robust algorithms in this work. First layer of proposed multi-layer architecture have been implemented at the system layer. Developed AC optimal power flow (AC-OPF) generates fair price for all DR and non-DR loads which is used as a control signal for second layer. Second layer controls DR load at buildings using a developed look-ahead robust controller. Load aggregator collects information from all buildings and send aggregated load to the system optimizer. Due to the different time scale at these two management layers, time coordination scheme is developed. Robust and deterministic controllers

  5. Improving the vibration suppression capabilities of a magneto-rheological damper using hybrid active and semi-active control

    Science.gov (United States)

    Ullah Khan, Irfan; Wagg, David; Sims, Neil D.

    2016-08-01

    This paper presents a new hybrid active and semi-active control method for vibration suppression in flexible structures. The method uses a combination of a semi-active device and an active control actuator situated elsewhere in the structure to suppress vibrations. The key novelty is to use the hybrid controller to enable the magneto-rheological damper to achieve a performance as close to a fully active device as possible. This is achieved by ensuring that the active actuator can assist the magneto-rheological damper in the regions where energy is required. In addition, the hybrid active and semi-active controller is designed to minimize the switching of the semi-active controller. The control framework used is the immersion and invariance control technique in combination with sliding mode control. A two degree-of-freedom system with lightly damped resonances is used as an example system. Both numerical and experimental results are generated for this system, and then compared as part of a validation study. The experimental system uses hardware-in-the-loop to simulate the effect of both the degrees-of-freedom. The results show that the concept is viable both numerically and experimentally, and improved vibration suppression results can be obtained for the magneto-rheological damper that approach the performance of an active device.

  6. The role of nuclear techniques in the control of agricultural pests and stored grains insects

    International Nuclear Information System (INIS)

    Peaceful applications of nuclear techniques in agriculture in general, and pest control specifically, are very numerous. Although this field of science is over a century old, its rapid developments occurred only in the last few decades. In fact, the contribution of nuclear techniques to insect pest control during the last half century is one of the most important developments in this science. This article is devoted to discuss the most important and widely used applications of nuclear techniques, particularly ionizing radiation, in insect pest control. In particular, it deals with the subject of sterilizing insects for the purpose of insect pest control and/or eradication in the field and storage, irradiation disinfestation of sorted products, particularly cereals and pulses, facilitating international trade by avoiding quarantine barriers and its role in biological control of insect pests. (author)

  7. Technique for particle flow measuring in activation analysis

    International Nuclear Information System (INIS)

    The invention is refered to the methods of measuring particle flow in nuclear-physical methods of substance composition monitoring. The purpose of the invention is to simplify the process of particle flux measurement and improve the accuracy of analysis. To do this, ''clean'' foil is located behind the monitor, when irradiating ''thin'' monitor, located in front of the sample, and measuring induced radioactivity of radionuclide, produced from the monitor basic element. The value oa particle flow is assessed according to activity of radionuclide nuclei, introduced from monitor into the foil, due to nuclear transformation energy. Monitor thickness should exceed the maximal path of radionuclide nuclei in monitor substance. 1 fig

  8. Monitor and control of neuronal activities with femtosecond pulse laser

    Institute of Scientific and Technical Information of China (English)

    ZHOU Wei; LIU XiuLi; L(U) XiaoHua; LI JiaSong; LUO QingMing; ZENG ShaoQun

    2008-01-01

    Combined with the fluorescence labeling technique, two-photon microscopy excited with femtosecond pulse laser has become an important tool for neuroscience research. In this research, the calcium signals from neurons in rat cortex slice were monitored by a custom-built two-photon microscopy, and the spontaneous calcium signals and the pharmacological responses as well as the responses to femtosecond pulse laser stimulation were recorded. The results showed that the amplitude of the cal-cium signals increased in direct proportion to the corresponding electrical activities. Glutamate induced a calcium transient, but continuous application resulted in smaller response. Simultaneous monitoring of neuronal populations distinguished the neurons of different microcircuits. The femtosecond pulse laser induced local or global calcium signals in the pyramidal neurons. The approach of interrogation and control of neural activities using femtosecond pulse laser is non-contact, nondestructive, repeatable, and without any additional substrates, which will contribute to the development of neuroscience.

  9. Optimum Setting of Controller Using Soft Computing Techniques for a Chemical System

    Directory of Open Access Journals (Sweden)

    G. Glandevadhas

    2011-01-01

    Full Text Available Problem statement: The aim of this study is to present an intelligent tuning technique for PID controller that are simple and still result in good closed loop behavior. The idea is to start with a tuned conventional PID controller, replace it with an equivalent intelligent controllers like Fuzzy, ANN, Genetic and PSO techniques implies fine tuned nonlinear PID controller which is most suitable for nonlinear process like Continuous stirred tank reactor. The performance of various optimization techniques and intelligent techniques are compared. Approach: In this study we present soft computing techniques to design and tune the PID controller. The objective is tominimise the steady state error and to obtain the optimum response. Results: The comparisons amoung the Conventional PID, Fuzzy Sliding PID, Simulated Anneling PID and PSO tuned PID controllers PSO PID implies better result for the nonlinear chemical process. Conclusion: With the nonlinear model of CSTR process the PSO tuned PID controller implies the optimum response for both setpoint and load variations.

  10. Prediction control of active power filters

    Institute of Scientific and Technical Information of China (English)

    王莉娜; 罗安

    2003-01-01

    A prediction method to obtain harmonic reference for active power filter is presented. It is a new use ofthe adaptive predictive filter based on FIR. The delay inherent in digital controller is successfully compensated by u-sing the proposed method, and the computing load is not very large compared with the conventional method. Moreo-ver, no additional hardware is needed. Its DSP-based realization is also presented, which is characterized by time-va-riant rate sampling, quasi synchronous sampling, and synchronous operation among the line frequency, PWM gener-ating and sampling in A/D unit. Synchronous operation releases the limitation on PWM modulation ratio and guar-antees that the electrical noises resulting from the switching operation of IGBTs do not interfere with the sampledcurrent. The simulation and experimental results verify the satisfactory performance of the proposed method.

  11. Indirect robust control of agile missile via Theta-D technique

    Institute of Scientific and Technical Information of China (English)

    Di ZHOU; Quan LI

    2014-01-01

    An agile missile with tail fins and pulse thrusters has continuous and discontinuous control inputs. This brings certain difficulty to the autopilot design and stability analysis. Indirect robust control via Theta-D technique is employed to handle this problem. An acceleration tracking system is formulated based on the nonlinear dynamics of agile missile. Considering the dynamics of actuators, there is an error between actual input and computed input. A robust control problem is formed by treating the error as input uncertainty. The robust control is equivalent to a nonlinear quadratic optimal control of the nominal system with a modified performance index including uncertainty bound. Theta-D technique is applied to solve the nonlinear optimal control problem to obtain the final control law. Numerical results show the effectiveness and robustness of the proposed strategy.

  12. Experimental techniques for screening of antiosteoporotic activity in postmenopausal osteoporosis.

    Science.gov (United States)

    Satpathy, Swaha; Patra, Arjun; Ahirwar, Bharti

    2015-12-01

    Postmenopausal osteoporosis, a silent epidemic, has become a major health hazard, afflicting about 50% of postmenopausal women worldwide and is thought to be a disease with one of the highest incidences in senile people. It is a chronic, progressive condition associated with micro-architectural deterioration of bone tissue that results in low bone mass, decreased bone strength that predisposes to an increased risk of fracture. Women are more likely to develop osteoporosis than men due to reduction in estrogen during menopause which leads to decline in bone formation and increase in bone resorption activity. Estrogen is able to suppress the production of proinflammatory cytokines like interleukin (IL)-1, IL-6, IL-7 and tumor necrosis factor (TNF-α). This is why these cytokines are elevated in postmenopausal women. In this review article we have made an attempt to collate the various methods and parameters most frequently used for screening of antiosteoporotic activity in postmenopausal osteoporosis. Pertaining to ovariectomized animal model, this is the most appropriate model for studying the efficacy of different drugs to prevent bone loss in postmenopausal osteoporosis.

  13. Ribosome-dependent activation of stringent control.

    Science.gov (United States)

    Brown, Alan; Fernández, Israel S; Gordiyenko, Yuliya; Ramakrishnan, V

    2016-06-01

    In order to survive, bacteria continually sense, and respond to, environmental fluctuations. Stringent control represents a key bacterial stress response to nutrient starvation that leads to rapid and comprehensive reprogramming of metabolic and transcriptional patterns. In general, transcription of genes for growth and proliferation is downregulated, while those important for survival and virulence are upregulated. Amino acid starvation is sensed by depletion of the aminoacylated tRNA pools, and this results in accumulation of ribosomes stalled with non-aminoacylated (uncharged) tRNA in the ribosomal A site. RelA is recruited to stalled ribosomes and activated to synthesize a hyperphosphorylated guanosine analogue, (p)ppGpp, which acts as a pleiotropic secondary messenger. However, structural information about how RelA recognizes stalled ribosomes and discriminates against aminoacylated tRNAs is missing. Here we present the cryo-electron microscopy structure of RelA bound to the bacterial ribosome stalled with uncharged tRNA. The structure reveals that RelA utilizes a distinct binding site compared to the translational factors, with a multi-domain architecture that wraps around a highly distorted A-site tRNA. The TGS (ThrRS, GTPase and SpoT) domain of RelA binds the CCA tail to orient the free 3' hydroxyl group of the terminal adenosine towards a β-strand, such that an aminoacylated tRNA at this position would be sterically precluded. The structure supports a model in which association of RelA with the ribosome suppresses auto-inhibition to activate synthesis of (p)ppGpp and initiate the stringent response. Since stringent control is responsible for the survival of pathogenic bacteria under stress conditions, and contributes to chronic infections and antibiotic tolerance, RelA represents a good target for the development of novel antibacterial therapeutics. PMID:27279228

  14. A quality control technique based on UV-VIS absorption spectroscopy for tequila distillery factories

    Science.gov (United States)

    Barbosa Garcia, O.; Ramos Ortiz, G.; Maldonado, J. L.; Pichardo Molina, J.; Meneses Nava, M. A.; Landgrave, Enrique; Cervantes, M. J.

    2006-02-01

    A low cost technique based on the UV-VIS absorption spectroscopy is presented for the quality control of the spirit drink known as tequila. It is shown that such spectra offer enough information to discriminate a given spirit drink from a group of bottled commercial tequilas. The technique was applied to white tequilas. Contrary to the reference analytic methods, such as chromatography, for this technique neither special personal training nor sophisticated instrumentations is required. By using hand-held instrumentation this technique can be applied in situ during the production process.

  15. History, progress and prospect for controlled ecological life support technique in China

    Science.gov (United States)

    Guo, Shuangsheng

    2016-07-01

    Constructing controlled ecological life support system is an important supporting condition for carrying out manned deep-space exploration and extraterrestrial inhabitation and development in the future. In China, the controlled ecological life support technique has gone through a developmental process of more than twenty years, undergoing the course of from conceptual research, to key unit-level technique and key system-level integrated technique, and from ground-based simulated tests to spaceflight demonstrating test, and gained many important stagy harvests. In this paper, the present status, subsistent problems and next plans in the domain of CELSS techniques in China are introduced briefly, so as to play a referential role for promoting development of the techniques internationally.

  16. Actively controlled thin-shell space optics

    Science.gov (United States)

    Denoyer, Keith K.; Flint, Eric M.; Main, John A.; Lindler, Jason E.

    2003-08-01

    Increasingly, scientific and military missions require the use of space-based optical systems. For example, new capabilities are required for imaging terrestrial like planets, for surveillance, and for directed energy applications. Given the difficulties in producing and launching large optics, it is doubtful that refinements of conventional technology will meet future needs, particularly in a cost-effective manner. To meet this need, recent research has been investigating the feasibility of a new class of ultra-lightweight think-skin optical elements that combine recent advances in lightweight thermally formed materials, active materials, and novel sensing and control architectures. If successful, the approach may lead to an order of magnitude reduction in space optics areal density, improved large scale manufacturing capability, and dramatic reductions in manufacturing and launch costs. In a recent effort, a one meter thin-film mirror like structure was fabricated. This paper provides an overview of tools used to model and simulate this structure as well as results from structural dynamic testing. In addition, progress in the area of non-contact global shape control using smart materials is presented.

  17. Active controlled studies in antibiotic drug development.

    Science.gov (United States)

    Dane, Aaron

    2011-01-01

    The increasing concern of antibacterial resistance has been well documented, as has the relative lack of antibiotic development. This paradox is in part due to challenges with clinical development of antibiotics. Because of their rapid progression, untreated bacterial infections are associated with significant morbidity and mortality. As a consequence, placebo-controlled studies of new agents are unethical. Rather, pivotal development studies are mostly conducted using non-inferiority designs versus an active comparator. Further, infections because of comparator-resistant isolates must usually be excluded from the trial programme. Unfortunately, the placebo-controlled data classically used in support of non-inferiority designs are largely unavailable for antibiotics. The only available data are from the 1930s and 1940s and their use is associated with significant concerns regarding constancy and assay sensitivity. Extended public debate on this challenge has led to proposed solutions by some in which these concerns are addressed by using very conservative approaches to trial design, endpoints and non-inferiority margins, in some cases leading to potentially impractical studies. To compound this challenge, different Regulatory Authorities seem to be taking different approaches to these key issues. If harmonisation does not occur, antibiotic development will become increasingly challenging, with the risk of further decreases in the amount of antibiotic drug development. However with clarity on Regulatory requirements and an ability to feasibly conduct global development programmes, it should be possible to bring much needed additional antibiotics to patients.

  18. High performance composites with active stiffness control.

    Science.gov (United States)

    Tridech, Charnwit; Maples, Henry A; Robinson, Paul; Bismarck, Alexander

    2013-09-25

    High performance carbon fiber reinforced composites with controllable stiffness could revolutionize the use of composite materials in structural applications. Here we describe a structural material, which has a stiffness that can be actively controlled on demand. Such a material could have applications in morphing wings or deployable structures. A carbon fiber reinforced-epoxy composite is described that can undergo an 88% reduction in flexural stiffness at elevated temperatures and fully recover when cooled, with no discernible damage or loss in properties. Once the stiffness has been reduced, the required deformations can be achieved at much lower actuation forces. For this proof-of-concept study a thin polyacrylamide (PAAm) layer was electrocoated onto carbon fibers that were then embedded into an epoxy matrix via resin infusion. Heating the PAAm coating above its glass transition temperature caused it to soften and allowed the fibers to slide within the matrix. To produce the stiffness change the carbon fibers were used as resistance heating elements by passing a current through them. When the PAAm coating had softened, the ability of the interphase to transfer load to the fibers was significantly reduced, greatly lowering the flexural stiffness of the composite. By changing the moisture content in PAAm fiber coating, the temperature at which the PAAm softens and the composites undergo a reduction in stiffness can be tuned. PMID:23978266

  19. Active Vibration Control of Axial Piston Machine using Higher Harmonic Least Mean Square Control of Swash Plate

    OpenAIRE

    Kim, Taeho; Ivantysynova, Monika

    2016-01-01

    Noise emission is a major drawback of the positive displacement machine. The noise source can be divided into structure borne noise source (SBNS) and fluid borne noise source (FBNS). Passive techniques such as valve plate optimization have been used for noise reduction of axial piston machines. However, passive techniques are only effective for limited operating conditions or at least need compromises in design. In this paper, active vibration control of swash plate is investigated for vibrat...

  20. Monolithic active pixel radiation detector with shielding techniques

    Energy Technology Data Exchange (ETDEWEB)

    Deptuch, Grzegorz W.

    2016-09-06

    A monolithic active pixel radiation detector including a method of fabricating thereof. The disclosed radiation detector can include a substrate comprising a silicon layer upon which electronics are configured. A plurality of channels can be formed on the silicon layer, wherein the plurality of channels are connected to sources of signals located in a bulk part of the substrate, and wherein the signals flow through electrically conducting vias established in an isolation oxide on the substrate. One or more nested wells can be configured from the substrate, wherein the nested wells assist in collecting charge carriers released in interaction with radiation and wherein the nested wells further separate the electronics from the sensing portion of the detector substrate. The detector can also be configured according to a thick SOA method of fabrication.

  1. Isotopic techniques for measuring the biological activity in plant rhizosphere

    International Nuclear Information System (INIS)

    The use of 14C made it possible to separate root respired CO2 and microbial CO2 resulting from exudates utilisation by the rhizosphere microflora. Measurements were done after wheat plants grown under axenic and non axenic conditions were placed during short period of time in an atmosphere contaning 14CO2. Under axenic conditions evolution of 14CO2 follows a bell shaped curve due to the brief appearance of labelled compounds translocated from the aerial part of the plants to the roots. In the presence of microorganisms, the maximum of activity due to root respiration is identical but immediately followed by a second peak of 14CO2 evolution that was attributed to the decomposition of labelled exudates by the microflora. The same observations resulted from the labelling of a grassland vegetation sampled with its soil and placed in the laboratory. Preliminary results obtained using this method of short term labelling of plants are presented here

  2. Manufacturing implementation of scatterometry and other techniques for 300-mm lithography tool controls

    Science.gov (United States)

    Wiltshire, T.; Corliss, D.; Brunner, T.; Ausschnitt, C.; Young, R.; Nielson, R.; Hwang, E.; Iannucci, J., Jr.

    2009-03-01

    Focus and dose control of lithography tools for leading edge semiconductor manufacturing are critical to obtaining acceptable process yields and device performance. The need for these controls is increasing due to the apparent limitation of optical water immersion lithography at NA values of approximately 1.35 and the need to use the same equipment for 45nm, 32nm, and 22nm node production. There is a rich history of lithographic controls using various techniques described in the literature. These techniques include (but are not limited to) Phase Grating Focus Monitoring1 (PGFM), optical CD control using optical overlay metrology equipment (OOCD)2,3, and in more recent years optical scatterometry4,5. Some of the techniques, even though they are technically sound, have not been practical to implement in volume manufacturing as controls for various reasons. This work describes the implementation and performance of two of these techniques (optical scatterometry and OOCD) in a volume 300mm production facility. Data to be reviewed include: - General implementation approach. - Scatterometry dose and focus stability data for 193nm immersion and 248nm dry lithography systems. - Analysis of the stability of optical scatterometry dose and focus deconvolution coefficients over time for 193nm immersion and 248nm dry systems. - Comparison between scatterometry and OOCD techniques for focus monitoring of 248nm dry systems. The presentation will also describe the practical issues with implementing these techniques as well as describe some possible extensions to enhance the current capabilities being described.

  3. Fast control technique based on peak current mode control of the output capacitor current

    OpenAIRE

    Alou Cervera, Pedro; García Suárez, Oscar; Oliver Ramírez, Jesús Angel; Cobos Márquez, José Antonio; Viejo de Frutos, Miriam del

    2010-01-01

    The control proposed and analyzed in this paper is based on the peak current mode control of the output capacitor current of a Buck converter. The output capacitor current loop provides fast dynamic response to the control since it behaves as a feed-forward of the load current while the voltage loop provides accurate steady state regulation. A simulation oriented averaged model of the proposed control has been developed to design the external voltage loop. As shown in simulations, with the co...

  4. The Changeless Technique Researches for City Flood Control and Reduced the Disaster

    Institute of Scientific and Technical Information of China (English)

    Chen Gangyi; OuYang Bolin; Xia Fan

    2006-01-01

    The make use of the stir kinetic energy conservation law, the theories and chaogeless technique build up for city flood control. Pass the system energy conversion or deliver with contain of second circulation, carry out city flood control and reduced the disaster that develops the artificial lake. It is advantageous to the improvement city ecosystem environment and resources of water that is missing.

  5. Using GPS instruments and GIS techniques in data management for insect pest control programs

    International Nuclear Information System (INIS)

    This interactive tutorial CD entitled 'Using GPS Instruments and GIS Techniques in Data Management for Insect Pest Control Programs' was developed by Micha silver of the Arava Development Co., Sapir, Israel, and includes step-by-step hands on lessons on the use of GPS/GIS in support of area-wide pest control operations

  6. A research program in active control/aeroelasticity in the JIAFS at NASA Langley Research Center

    Science.gov (United States)

    Whitesides, J. L.

    1984-01-01

    A control law synthesis methodology for multifunctional active control system to satisfy root-mean-square load and response constraints as well as to meet stability robustness requirements at plant input and output was developed. Modern control theory, singular value analysis and optimization techniques were utilized. All stability and response derivative expressions were derived analytically for sensitivity study. The software is incorporated as an update to the AB/LAD general control design software package PADLOCS.

  7. PERFORMANCE OF PID CONTROLLER OF NONLINEAR SYSTEM USING SWARM INTELLIGENCE TECHNIQUES

    Directory of Open Access Journals (Sweden)

    Neeraj Jain

    2016-07-01

    Full Text Available In this paper swarm intelligence based PID controller tuning is proposed for a nonlinear ball and hoop system. Particle swarm optimization (PSO, Artificial bee colony (ABC, Bacterial foraging optimization (BFO is some example of swarm intelligence techniques which are focused for PID controller tuning. These algorithms are also tested on perturbed ball and hoop model. Integral square error (ISE based performance index is used for finding the best possible value of controller parameters. Matlab software is used for designing the ball and hoop model. It is found that these swarm intelligence techniques have easy implementation & lesser settling & rise time compare to conventional methods.

  8. Innovative techniques to analyze time series of geomagnetic activity indices

    Science.gov (United States)

    Balasis, Georgios; Papadimitriou, Constantinos; Daglis, Ioannis A.; Potirakis, Stelios M.; Eftaxias, Konstantinos

    2016-04-01

    Magnetic storms are undoubtedly among the most important phenomena in space physics and also a central subject of space weather. The non-extensive Tsallis entropy has been recently introduced, as an effective complexity measure for the analysis of the geomagnetic activity Dst index. The Tsallis entropy sensitively shows the complexity dissimilarity among different "physiological" (normal) and "pathological" states (intense magnetic storms). More precisely, the Tsallis entropy implies the emergence of two distinct patterns: (i) a pattern associated with the intense magnetic storms, which is characterized by a higher degree of organization, and (ii) a pattern associated with normal periods, which is characterized by a lower degree of organization. Other entropy measures such as Block Entropy, T-Complexity, Approximate Entropy, Sample Entropy and Fuzzy Entropy verify the above mentioned result. Importantly, the wavelet spectral analysis in terms of Hurst exponent, H, also shows the existence of two different patterns: (i) a pattern associated with the intense magnetic storms, which is characterized by a fractional Brownian persistent behavior (ii) a pattern associated with normal periods, which is characterized by a fractional Brownian anti-persistent behavior. Finally, we observe universality in the magnetic storm and earthquake dynamics, on a basis of a modified form of the Gutenberg-Richter law for the Tsallis statistics. This finding suggests a common approach to the interpretation of both phenomena in terms of the same driving physical mechanism. Signatures of discrete scale invariance in Dst time series further supports the aforementioned proposal.

  9. Remote Control Techniques to the Digital Storage Oscilloscope by GPIB and VISA

    Directory of Open Access Journals (Sweden)

    Faquan Zhang

    2013-04-01

    Full Text Available Some techniques of controlling remotely the digital storage oscilloscope were proposed including VISA, VXIplug&play drivers, TVC and IVI-COM drivers. By means of GPIB and VISA, several application development environments could be used to develop remote control techniques to the digital storage oscilloscope. The programming language of Visual C++ was used to develop software. With the help of VISA and the dynamic link library, remote control to the digital storage oscilloscope through network was completed. All operations to the digital storage oscilloscope including parameters setup, data acquisition, waveform acquisition and storage, data processing were implemented in a remote place. The results show that the techniques of remote control are convenient and efficient and fit for experiments of scientific research and practical projects.

  10. Development of a generic activities model of command and control

    OpenAIRE

    Stanton, NA; Baber, C; Walker, GH; Houghton, RJ; McMaster, R.; Stewart, R; Harris, D.; Jenkins, DP; Young, MS; Salmon, PM

    2008-01-01

    This paper reports on five different models of command and control. Four different models are reviewed: a process model, a contextual control model, a decision ladder model and a functional model. Further to this, command and control activities are analysed in three distinct domains: armed forces, emergency services and civilian services. From this analysis, taxonomies of command and control activities are developed that give rise to an activities model of command and control. This model w...

  11. Online process control for directional solidification by ultrasonic pulse echo technique.

    Science.gov (United States)

    Drevermann, A; Pickmann, C; Tiefers, R; Zimmermann, G

    2004-04-01

    A method of controlling the actual growth velocity during directional solidification based on ultrasound has been developed. For this purpose a pulse echo technique is used to measure the actual solidification rate online. This quantity is used to control the furnace velocity. Solidification experiments with metallic alloys and constant furnace velocity often result in non-steady actual solidification rates. Experiments carried out with online process control demonstrate that a really steady-state solidification with a constant solidification rate is achieved.

  12. A novel technique to control ice cream freezing by electrical characteristics analysis

    OpenAIRE

    Grossi, Marco; Lazzarini, Roberto; Lanzoni, Massimo; Riccò, Bruno

    2011-01-01

    International audience The freezing process is very important in ice cream production affecting quality, taste and yield of the finished product. Batch freezer machines use different control techniques to tightly control the freezing process, based on monitoring of the temperature and/or the viscosity (i.e. consistency) of the product. Temperature control, however, features low sensitivity and need calibration for different product compositions , while product viscosity is essentially infe...

  13. Performance index based learning controls for the partial non-regular systems using lifting technique

    Institute of Scientific and Technical Information of China (English)

    Shengyue YANG; Xiaoping FAN; Zhihua QU

    2009-01-01

    Deficiencies of the performance-based iterative learning control (ILC) for the non-regular systems are investigated in detail, then a faster control input updating and lifting technique is introduced in the design of performance index based ILCs for the partial non-regular systems. Two kinds of optimal ILCs based on different performance indices are considered. Finally, simulation examples are given to illustrate the feasibility of the proposed learning controls.

  14. Supervisory Control Technique For An Assembly Workstation As A Dynamic Discrete Event System

    Directory of Open Access Journals (Sweden)

    Daniela Cristina CERNEGA

    2001-12-01

    Full Text Available This paper proposes a control problem statement in the framework of supervisory control technique for the assembly workstations. A desired behaviour of an assembly workstation is analysed. The behaviour of such a workstation is cyclic and some linguistic properties are established. In this paper, it is proposed an algorithm for the computation of the supremal controllable language of the closed system desired language. Copyright © 2001 IFAC.

  15. Experimental Investigation of Active Noise Controller for Internal Combustion Engine Exhaust System

    Science.gov (United States)

    Wu, Jian-Da; Chen, Chih-Keng; Lee, Chun-Ying; Lee, Tian-Hua

    2002-10-01

    Two active noise control (ANC) algorithms for internal combustion engine exhaust systems are developed and their performances are compared in various experiments. The first controller is based on the filtered-x least mean square (FXLMS) algorithm with feedback neutralization, while the second is a fixed controller with a gain-scheduled active control technique for broadband attenuation with thermal effects. Both control algorithms are implemented on a digital signal processing (DSP) platform. Experiments are carried out to evaluate the attenuation performance of the proposed active noise control systems for an engine exhaust system. The results of the experiments indicate that both the adaptive controller and the gain-scheduled controller effectively suppress the noise of engine exhaust systems. The experimental comparison and analysis of the proposed controllers are also described.

  16. A Novel Implementation of RISI Controller Employing Adaptive Clock Gating Technique

    Directory of Open Access Journals (Sweden)

    M.Kamaraju

    2011-11-01

    Full Text Available With the scaling of technology and the need for higher performance and more functionality power dissipation is becoming a major issue for controller design. Interrupt based programming is widely used for interfacing a processor with peripherals. The proposed architecture implements a mechanism which combines interrupt controller and RIS (Reduced Instruction Set CPU (Central processing unit on a single die. RISI Controller takes only one cycle for both interrupt request generation and acknowledgement. The architecture have a dynamic control unit which consists of a program flow controller, interrupt controller and I/O controller. Adaptive clock gating technique is used to reduce power consumption in the dynamic control unit. The controller consumes a power of 174µw@1MHz and is implemented in verilog HDL using Xilinx platform

  17. Air pollution control techniques and a case study of industrial air emissions

    International Nuclear Information System (INIS)

    Air pollutants are the most dangerous type of pollution and they effect our environment the worst. The main air pollutants are CO/sub 2/, CO, NOx, SOx and particulate matter. These pollutants are causing some major environmental and health concerns. There are number of techniques to control these emissions to the atmosphere. The flue gas data of boilers and generators from ICI polyester industry is also included in this paper. The techniques in use to control the pollutants are discussed. One of the most common techniques is the switching of the fuel. The Natural gas emits almost 30 percent less carbon dioxide than oil, and just under 45 percent less carbon dioxide than coal. Emissions of particulates from natural gas combustion are 90 percent lower than from the combustion of oil, and 99 percent lower than burning coal. Natural gas emits virtually no sulfur dioxide, and upto 80 percent less nitrogen oxides than the combustion of coal. Similarly, use of compressed natural gas in vehicle reduces the amount of these emissions considerably. The other methods for the control and reduction of these emissions are combustion control techniques, Flue gas treatment and Fuel re-burning. NOx can be reduced considerably by combustion control techniques like Low excess air, staged air combustion, staged fuel combustion, external flue gas recirculation, Fuel induced recirculation and steam/water injection. The flue gas treatments like selective non-catalytic reduction (SNCR) and selective catalytic reduction (SCR) are also used for reduction of NOx. (author)

  18. Automotive active noise control (ANC) system. Jidoshayo active noise control (ANC) system

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, S. (Nissan Motor Co. Ltd., Tokyo (Japan))

    1992-11-25

    This paper introduces a successful development of an active noise control (ANC) system that selects and controls noise in an automobile compartment. This is a system that Nissan has developed for practical use for the first time in the world by using an adaptive control theory and a digital signal processor (DSP) that uses ultra-high speed operating elements. The principle for noise silencing in the ANC system utilizes interference of cyclic amplitude of sound with opposite phase. Sounds in an automobile include informative sounds, agreeable sounds, and noise, and combinations of these sounds work complexly on people in a car, of which extent varies depending on individuals. The adaptive control minimizes sounds picked up by a microphone into controlled speaker sound via an multiple error filtered algorithm (MEF-[sub X]LMS) and an adaptive digital filter. Major components of the system include a microphone, a speaker, and a control unit (comprising the adaptive algorithm and the adaptive filter), all having been developed newly. A DSP that operates on ultra-high speed operating elements was used for speedy compliance with complex algorithms, so that the controlled sound combined of engine noise with compartment sound field can be calculated. The noise was reduced by more than 10 dB at maximum. 7 figs.

  19. Active Control of Automotive Intake Noise under Rapid Acceleration using the Co-FXLMS Algorithm

    Science.gov (United States)

    Lee, Hae-Jin; Lee, Gyeong-Tae; Oh, Jae-Eung

    The method of reducing automotive intake noise can be classified by passive and active control techniques. However, passive control has a limited effect of noise reduction at low frequency range (below 500 Hz) and is limited by the space of the engine room. However, active control can overcome these passive control limitations. The active control technique mostly uses the Least-Mean-Square (LMS) algorithm, because the LMS algorithm can easily obtain the complex transfer function in real-time, particularly when the Filtered-X LMS (FXLMS) algorithm is applied to an active noise control (ANC) system. However, the convergence performance of the LMS algorithm decreases significantly when the FXLMS algorithm is applied to the active control of intake noise under rapidly accelerating driving conditions. Therefore, in this study, the Co-FXLMS algorithm was proposed to improve the control performance of the FXLMS algorithm during rapid acceleration. The Co-FXLMS algorithm is realized by using an estimate of the cross correlation between the adaptation error and the filtered input signal to control the step size. The performance of the Co-FXLMS algorithm is presented in comparison with that of the FXLMS algorithm. Experimental results show that active noise control using Co-FXLMS is effective in reducing automotive intake noise during rapid acceleration.

  20. New Control Technique Applied in Dynamic Voltage Restorer for Voltage Sag Mitigation

    Directory of Open Access Journals (Sweden)

    Rosli Omar

    2010-01-01

    Full Text Available The Dynamic Voltage Restorer (DVR was a power electronics device that was able to compensate voltage sags on critical loads dynamically. The DVR consists of VSC, injection transformers, passive filters and energy storage (lead acid battery. By injecting an appropriate voltage, the DVR restores a voltage waveform and ensures constant load voltage. There were so many types of the control techniques being used in DVR for mitigating voltage sags. The efficiency of the DVR depends on the efficiency of the control technique involved in switching the inverter. Problem statement: Simulation and experimental investigation toward new algorithms development based on SVPWM. Understanding the nature of DVR and performance comparisons between the various controller technologies available. The proposed controller using space vector modulation techniques obtain higher amplitude modulation indexes if compared with conventional SPWM techniques. Moreover, space vector modulation techniques can be easily implemented using digital processors. Space vector PWM can produce about 15% higher output voltage than standard Sinusoidal PWM. Approach: The purpose of this research was to study the implementation of SVPWM in DVR. The proposed control algorithm was investigated through computer simulation by using PSCAD/EMTDC software. Results: From simulation and experimental results showed the effectiveness and efficiency of the proposed controller based on SVPWM in mitigating voltage sags in low voltage distribution systems. It was concluded that its controller also works well both in balance and unbalance conditions of voltages. Conclusion/Recommendations: The simulation and experimental results of a DVR using PSCAD/EMTDC software based on SVPWM technique showed clearly the performance of the DVR in mitigating voltage sags. The DVR operates without any difficulties to inject the appropriate voltage component to correct rapidly any anomaly in the supply voltage to keep the

  1. Reliable Wireless Data Acquisition and Control Techniques within Nuclear Hot Cell Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, J.L.; Tulenko, J.

    2000-09-20

    On this NEER project the University of Florida has investigated and applied advanced communications techniques to address data acquisition and control problems within the Fuel Conditioning Facility (FCF) of Argonne National Laboratory-West (ANL-W) in Idaho Falls. The goals of this project have been to investigate and apply wireless communications techniques to solve the problem of communicating with and controlling equipment and systems within a nuclear hot cell facility with its attendant high radiation levels. Different wireless techniques, including radio frequency, infrared and power line communications were reviewed. For each technique, the challenges of radiation-hardened implementation were addressed. In addition, it has been a project goal to achieve the highest level of system reliability to ensure safe nuclear operations. Achievement of these goals would allow the eventual elimination of through-the-wall, hardwired cabling that is currently employed in the hot cell, along wit h all of the attendant problems that limit measurement mobility and flexibility.

  2. ESTIMATION OF ACTIVATED ENERGY OF DESORPTION OF n—HEXANE ON ACTIVATED CARBONS BY PTD TECHNIQUE

    Institute of Scientific and Technical Information of China (English)

    LIZhong; WANGHongjuan; 等

    2001-01-01

    In this paper,six kinds of activated carbons such as Ag+-activated carbon,Cu2+activated carbon,Fe3+-activated carbon,activated carbon,Ba2+-activated carbon and Ca2+activated carbon were prepared.The model for estimating activated energy of desorption was established.Temperature-programmed desorption(TPD)experiments were conducted to measure the TPD curves of n-hexanol and then estimate the activation energy for desorption of n-hexanol on the activated carbons.Results showed that the activation energy for the desorption of n-hexanol on the Ag+-activated carbon,the Cu2+-activated carbon and the Fe3+-activated carbon were higher than those of n-hexanol on the activated carbon,the Ca2+-activated carbon and the Ba2+-activated carbon.

  3. ESTIMATION OF ACTIVATED ENERGY OF DESORPTION OF n-HEXANE ON ACTIVATED CARBONS BY TPD TECHNIQUE

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In this paper, six kinds of activated carbons such as Ag+-activated carbon, Cu2+-activated carbon, Fe3+- activated carbon, activated carbon, Ba2+- activated carbon and Ca2+-activated carbon were prepared. The model for estimating activated energy of desorption was established. Temperature-programmed desorption (TPD) experiments were conducted to measure the TPD curves of n-hexanol and then estimate the activation energy for desorption of n-hexanol on the activated carbons. Results showed that the activation energy for the desorption of n-hexanol on the Ag+- activated carbon, the Cu2+- activated carbon and the Fe3+- activated carbon were higher than those of n-hexanol on the activated carbon, the Ca2+- activated carbon and the Ba2+- activated carbon.

  4. A Low Phase Noise CMOS Quadrature Voltage Control Oscillator Using Clock Gated Technique

    OpenAIRE

    Jothi Baskar A; Kalpana R

    2015-01-01

    This project presents the low phase noise cmos quadrature voltage control oscillator using clock gating technique. Here the colpitts vco is used to split the capacitance in the Qvco circuit producing quadrature output. The startup condition in the oscillator is improved by using enhancement [12].This QVCO performs the operation anti phase injection locking fordevice reuse [8]. The new clock gating technique is used to reduce the power with thepower supply 1.5v. The QVCO uses a ...

  5. Advances in insect population control by the sterile-male technique

    International Nuclear Information System (INIS)

    The sterile male technique has been successfully used in the control or eradication of at least eight species of insects in experimental or field trials. In view of the importance of the method the IAEA convened a Panel of experts in July 1964 to review the progress made in research on the application of the technique and to suggest future actions. The findings of the Panel are published in this Technical Report. 52 refs, 10 figs, 10 tabs

  6. Prospects of pharmaceuticals and biopharmaceuticals loaded microparticles prepared by double emulsion technique for controlled delivery

    OpenAIRE

    Giri, Tapan Kumar; Choudhary, Chhatrapal; Ajazuddin,; Alexander, Amit; Badwaik, Hemant; Tripathi, Dulal Krishna

    2012-01-01

    Several methods and techniques are potentially useful for the preparation of microparticles in the field of controlled drug delivery. The type and the size of the microparticles, the entrapment, release characteristics and stability of drug in microparticles in the formulations are dependent on the method used. One of the most common methods of preparing microparticles is the single emulsion technique. Poorly soluble, lipophilic drugs are successfully retained within the microparticles prepar...

  7. Application of Multivariable Statistical Techniques in Plant-wide WWTP Control Strategies Analysis

    DEFF Research Database (Denmark)

    Flores Alsina, Xavier; Comas, J.; Rodríguez-Roda, I.;

    2007-01-01

    The main objective of this paper is to present the application of selected multivariable statistical techniques in plant-wide wastewater treatment plant (WWTP) control strategies analysis. In this study, cluster analysis (CA), principal component analysis/factor analysis (PCA/FA) and discriminant...... analysis (DA) are applied to the evaluation matrix data set obtained by simulation of several control strategies applied to the plant-wide IWA Benchmark Simulation Model No 2 (BSM2). These techniques allow i) to determine natural groups or clusters of control strategies with a similar behaviour, ii......) to find and interpret hidden, complex and casual relation features in the data set and iii) to identify important discriminant variables within the groups found by the cluster analysis. This study illustrates the usefulness of multivariable statistical techniques for both analysis and interpretation...

  8. Recent developments in the techniques of controlling and measuring suction in unsaturated soils

    CERN Document Server

    Delage, Pierre; Tarantino, Alessandro

    2008-01-01

    The difficulty of measuring and controlling suction in unsaturated soils is one of the reasons why the development of the mechanics of unsaturated soils has not been as advanced as that of saturated soils. However, significant developments have been carried out in the last decade in this regard. In this paper, a re-view of some developments carried out in the techniques of controlling suction by using the axis translation, the osmotic method and the vapour control technique is presented. The paper also deals with some recent de-velopments in the direct measurement of suction by using high capacity tensiometers and in the measurement of high suction by using high range psychrometers. The recent progresses made in these techniques have been significant and will certainly help further experimental investigation of the hydromechanical behaviour of un-saturated soils.

  9. A Modified Robust Queue Management with Feedback Compensation Technique to Manage the Congestion Control in Wireless Communication Networks

    Directory of Open Access Journals (Sweden)

    V.SAVITHA

    2012-08-01

    Full Text Available At present there has been a tremendous growth in the computer networks and wireless networks. Due to the enormous growth of voice, audio, video and data applications over the wireless networks, therequirement of congestion control mechanism is also developing along with the development of wireless network applications. The congestion in the network has drastically affected the Quality of Service (QoSrequirements of the applications. Active Queue Management (AQM is the technique of signaling Transmission Control Protocol (TCP sources from middle routers and its major purpose is to lessen the congestion and also satisfy the QoS requirements. In this paper, Modified Robust Queue Management with Feedback Compensation Technique is proposed that helps to reduce the delay and low loss service. The proposed technique is based on feedback compensation technique and the algorithm used in this Modified RQM is called Modified Proportional Integral based series compensation, and Position feedback compensation (Modified PIP. The performance of Modified RQM with Feedback (MFPIP is evaluated against the existing RQM in terms of packet loss, queue size, unloaded buffer size, End-to-End delay, bandwidth utilization and jitter value. It is revealed from theresults that the Modified RQM with Feedback (MFPIP is more effective in handling the congestion control in Wireless Communication Networks.

  10. Performance Evaluation of Virtualization Techniques for Control and Access of Storage Systems in Data Center Applications

    Science.gov (United States)

    Ahmadi, Mohammad Reza

    2013-09-01

    Virtualization is a new technology that creates virtual environments based on the existing physical resources. This article evaluates effect of virtualization techniques on control servers and access method in storage systems [1, 2]. In control server virtualization, we have presented a tile based evaluation based on heterogeneous workloads to compare several key parameters and demonstrate effectiveness of virtualization techniques. Moreover, we have evaluated the virtualized model using VMotion techniques and maximum consolidation. In access method, we have prepared three different scenarios using direct, semi-virtual, and virtual attachment models. We have evaluated the proposed models with several workloads including OLTP database, data streaming, file server, web server, etc. Results of evaluation for different criteria confirm that server virtualization technique has high throughput and CPU usage as well as good performance with noticeable agility. Also virtual technique is a successful alternative for accessing to the storage systems especially in large capacity systems. This technique can therefore be an effective solution for expansion of storage area and reduction of access time. Results of different evaluation and measurements demonstrate that the virtualization in control server and full virtual access provide better performance and more agility as well as more utilization in the systems and improve business continuity plan.

  11. Achieving Thin Films with Micro/Nano-Scale Controllable Morphology by Glancing Angle Deposition Technique

    Institute of Scientific and Technical Information of China (English)

    JIANG Shao-Ji; WANG Chao-Yi; TANG Ji-Jia; HU Lin-Xin

    2008-01-01

    @@ We demonstrate that thin films with micro/nanometre controllable morphology can be fabricated by the glancing angle deposition (GLAD) technique which is a physical vapour deposition technique.In this technique, there are parameters which determine the morphology of the thin films: the incident angle, ratio of the deposition rate with respect to the substrate rotation rate, nature of the material being deposited, etc.We fabricate the morphology of column, pillar, helices, zigzag and study the parameters which determine morphology by given some examples of SEM.

  12. Influence of inhaler technique on asthma and COPD control: a multicenter experience

    Science.gov (United States)

    Dudvarski Ilic, Aleksandra; Zugic, Vladimir; Zvezdin, Biljana; Kopitovic, Ivan; Cekerevac, Ivan; Cupurdija, Vojislav; Perhoc, Nela; Veljkovic, Vesna; Barac, Aleksandra

    2016-01-01

    Background The successful management of asthma and chronic obstructive pulmonary disease (COPD) mostly depends on adherence to inhalation drug therapy, the usage of which is commonly associated with many difficulties in real life. Improvement of patients’ adherence to inhalation technique could lead to a better outcome in the treatment of asthma and COPD. Objective The aim of this study was to assess the utility of inhalation technique in clinical and functional control of asthma and COPD during a 3-month follow-up. Methods A total of 312 patients with asthma or COPD who used dry powder Turbuhaler were enrolled in this observational study. During three visits (once a month), training in seven-step inhalation technique was given and it was practically demonstrated. Correctness of patients’ usage of inhaler was assessed in three visits by scoring each of the seven steps during administration of inhaler dose. Assessment of disease control was done at each visit and evaluated as: fully controlled, partially controlled, or uncontrolled. Patients’ subjective perception of the simplicity of inhalation technique, disease control, and quality of life were assessed by using specially designed questionnaires. Results Significant improvement in inhalation technique was achieved after the third visit compared to the first one, as measured by the seven-step inhaler usage score (5.94 and 6.82, respectively; Psuccessful respiratory disease treatment. Therefore, health care professionals should insist on educational programs aimed at improving patients’ inhalation technique with different devices, resulting in better long-term disease control and improved quality of life. PMID:27785007

  13. SYSTEMATIC SCANNING ELECTRON MICROSCOPY TECHNIQUE FOR EVALUATING COMBINED BIOLOIGCAL/GRANULAR ACTIVATED CARBON TREATMENT PROCESSES

    Science.gov (United States)

    A systematic scanning election microscope analytical technique has been developed to examine granular activated carbon used a a medium for biomass attachment in liquid waste treatment. The procedure allows for the objective monitoring, comparing, and trouble shooting of combined ...

  14. Implementation of closed loop control technique for improving the performances of PWM inverter-A review

    Directory of Open Access Journals (Sweden)

    V. M. Deshmukh

    2014-10-01

    Full Text Available this review paper presents closed loop control techniques for controlling the inverter working under different load or KVA ratings. The control strategy of the inverter must guarantee its output waveforms to be sinusoidal with fundamental harmonic. For this purpose, close loop current control strategies such as H∞ repetitive controller, dual closed-loop feedback control, Adaptive Voltage Control, SRFPI controller, Optimal Neural Controller, etc. have been used to meet the power quality requirements imposed by IEEE Interconnection Standards. Based on present scenario regarding energy crises, immediate action is the use of different renewable energy sources (RESs . Out of RESs, solar is gaining more attention. It is very important to design and developed a system which should be efficient enough to utilize the extracted energy for different types of load and feeding of energy into utility grid. Since experimentation and comparison of such inverter models on hardware being relatively expensive, the latest computing tool like MATLAB are considered to be a better alternative to simulate the outcomes of such expensive systems. The proposed closed loop control technique for the inverter working under linear and nonlinear system will be implemented in MATLAB/SIMULINK working platform and results will be analyzed to check its benefits.

  15. Power electronics and control techniques for maximum energy harvesting in photovoltaic systems

    CERN Document Server

    Femia, Nicola

    2012-01-01

    Incentives provided by European governments have resulted in the rapid growth of the photovoltaic (PV) market. Many PV modules are now commercially available, and there are a number of power electronic systems for processing the electrical power produced by PV systems, especially for grid-connected applications. Filling a gap in the literature, Power Electronics and Control Techniques for Maximum Energy Harvesting in Photovoltaic Systems brings together research on control circuits, systems, and techniques dedicated to the maximization of the electrical power produced by a photovoltaic (PV) so

  16. Fast control technique for high frequency (5MHz) DC/DC integrated converter

    OpenAIRE

    Viejo de Frutos, Miriam del; Alou Cervera, Pedro; Oliver Ramírez, Jesús Angel; García Suárez, Oscar; Cobos Márquez, José Antonio

    2010-01-01

    A switching frequency of 5 MHz allows the integration in a chip of a low power (10W) DC/DC converter. Although this switching frequency would make feasible a voltage mode control with 1MHz bandwidth, the parasitics and robustness don't allow such a high frequency bandwidth. This paper proposes a fast control technique that helps to optimize the dynamic response of high frequency DC/DC converter. The control proposed and analyzed in this paper is based on the peak current mode control of the o...

  17. Sliding mode pulse-width modulation technique for direct torque controlled induction motor drive

    Science.gov (United States)

    Bounadja, M.; Belarbi, A. W.; Belmadani, B.

    2010-05-01

    This paper presents a novel pulse-width modulation technique based sliding mode approach for direct torque control of an induction machine drive. Methodology begins with a sliding mode control of machine's torque and stator flux to generate the reference voltage vector and to reduce parameters sensitivity. Then, the switching control of the three-phase inverter is developed using sliding mode concept to make the system tracking reference voltage inputs. The main features of the proposed methodologies are the high tracking accuracy and the much easier implementation compared to the space vector modulation. Simulations are carried out to confirm the effectiveness of proposed control algorithms.

  18. Genetic Fuzzy Logic Control Technique for a Mobile Robot Tracking a Moving Target

    Directory of Open Access Journals (Sweden)

    Karim Benbouabdallah

    2013-01-01

    Full Text Available Target tracking is a crucial function for an autonomous mobile robot navigating in unknown environments. This paper presents a mobile robot target tracking approach based on artificial intelligence techniques. The proposed controller calculates both the mobile robot linear and angular velocities from the distance and angle that separate it to the moving target. The controller was designed using fuzzy logics theory and then, a genetic algorithm was applied to optimize the scaling factors of the fuzzy logic controller for better accuracy and smoothness of the robot trajectory. Simulation results illustrate that the proposed controller leads to good performances in terms of computational time and tracking errors convergence.

  19. Active Control of Inlet Noise on the JT15D Turbofan Engine

    Science.gov (United States)

    Smith, Jerome P.; Hutcheson, Florence V.; Burdisso, Ricardo A.; Fuller, Chris R.

    1999-01-01

    This report presents the key results obtained by the Vibration and Acoustics Laboratories at Virginia Tech over the year from November 1997 to December 1998 on the Active Noise Control of Turbofan Engines research project funded by NASA Langley Research Center. The concept of implementing active noise control techniques with fuselage-mounted error sensors is investigated both analytically and experimentally. The analytical part of the project involves the continued development of an advanced modeling technique to provide prediction and design guidelines for application of active noise control techniques to large, realistic high bypass engines of the type on which active control methods are expected to be applied. Results from the advanced analytical model are presented that show the effectiveness of the control strategies, and the analytical results presented for fuselage error sensors show good agreement with the experimentally observed results and provide additional insight into the control phenomena. Additional analytical results are presented for active noise control used in conjunction with a wavenumber sensing technique. The experimental work is carried out on a running JT15D turbofan jet engine in a test stand at Virginia Tech. The control strategy used in these tests was the feedforward Filtered-X LMS algorithm. The control inputs were supplied by single and multiple circumferential arrays of acoustic sources equipped with neodymium iron cobalt magnets mounted upstream of the fan. The reference signal was obtained from an inlet mounted eddy current probe. The error signals were obtained from a number of pressure transducers flush-mounted in a simulated fuselage section mounted in the engine test cell. The active control methods are investigated when implemented with the control sources embedded within the acoustically absorptive material on a passively-lined inlet. The experimental results show that the combination of active control techniques with fuselage

  20. Optical Sensor/Actuator Locations for Active Structural Acoustic Control

    Science.gov (United States)

    Padula, Sharon L.; Palumbo, Daniel L.; Kincaid, Rex K.

    1998-01-01

    Researchers at NASA Langley Research Center have extensive experience using active structural acoustic control (ASAC) for aircraft interior noise reduction. One aspect of ASAC involves the selection of optimum locations for microphone sensors and force actuators. This paper explains the importance of sensor/actuator selection, reviews optimization techniques, and summarizes experimental and numerical results. Three combinatorial optimization problems are described. Two involve the determination of the number and position of piezoelectric actuators, and the other involves the determination of the number and location of the sensors. For each case, a solution method is suggested, and typical results are examined. The first case, a simplified problem with simulated data, is used to illustrate the method. The second and third cases are more representative of the potential of the method and use measured data. The three case studies and laboratory test results establish the usefulness of the numerical methods.

  1. The Potential for the Integration of Nuclear Techniques in Arthropod Biological Control

    International Nuclear Information System (INIS)

    Biological control is today being practised more widely than ever before and its popularity looks set to increase further in the future. While the discipline has historically been dominated by 'classical' biological control (the one-off introduction of natural enemies to control pests in their adventive range) augmentative biological control (the repeated introduction of biocontrol agents to a particular crop or forest) has increased substantially over the past 20 years and is likely to increase in importance further in the future. This view is supported by an assessment of some of the key issues facing the discipline of biological control today. There is no clear role for nuclear techniques in the future of classical biological control. However the use of irradiation as a means of creating increased rates of mutation in natural enemy populations being selected for enhanced beneficial traits (such as insecticide resistance), might be useful and could be investigated further. There is scope for the use of irradiation in killing or sterilising insect diets and hosts, a technique which has been used for over 25 years without gaining wide acceptance. Augmentative biological control as an adjunct to SIT may have a role in future pest control campaigns, although it is likely to prove difficult to provide a clear economic justification given the technical difficulties of measuring separately the effects of the two techniques. It is suggested that the technical advances in project development and implementation (e.g. insect rearing techniques and field application) which have been made by SIT practitioners have a potentially useful role in assisting the development of improved production and delivery of biological control agents for augmentative release (author)

  2. Optimal designs for dose finding studies with an active control

    OpenAIRE

    Benda, Norbert; Bretz, Frank; Dette, Holger; Kiss , Christine

    2011-01-01

    Dose finding studies often compare several doses of a new compound with a marketed standard treatment as an active control. In the past, however, research has focused mostly on experimental designs for placebo-controlled dose finding studies. To the best of our knowledge, optimal designs for dose finding studies with an active control have not been considered so far. As the statistical analysis for an active controlled dose finding study can be formulated in terms of a mixture ...

  3. Low Activity Waste Feed Process Control Strategy

    International Nuclear Information System (INIS)

    The primary purpose of this document is to describe the overall process control strategy for monitoring and controlling the functions associated with the Phase 1B high-level waste feed delivery. This document provides the basis for process monitoring and control functions and requirements needed throughput the double-shell tank system during Phase 1 high-level waste feed delivery. This document is intended to be used by (1) the developers of the future Process Control Plan and (2) the developers of the monitoring and control system

  4. Low Activity Waste Feed Process Control Strategy

    Energy Technology Data Exchange (ETDEWEB)

    STAEHR, T.W.

    2000-06-14

    The primary purpose of this document is to describe the overall process control strategy for monitoring and controlling the functions associated with the Phase 1B high-level waste feed delivery. This document provides the basis for process monitoring and control functions and requirements needed throughput the double-shell tank system during Phase 1 high-level waste feed delivery. This document is intended to be used by (1) the developers of the future Process Control Plan and (2) the developers of the monitoring and control system.

  5. Active control of smart structures : an overall approach

    OpenAIRE

    Nestorović Tamara; Trajkov Miroslav

    2010-01-01

    The paper presents active control of smart structures within a focused frame of piezoelectric applications in active vibration and noise attenuation with potentials for the use in mechanical and civil engineering. An overall approach to active control of piezoelectric structures involves subsequent steps of modeling, control, simulation, experimental verification and implementation. Each of these steps is regarded in details. Different application examples showing the feasibility of the activ...

  6. Management Control of Public and Not-for-Profit Activities

    OpenAIRE

    Hofstede, G.

    1981-01-01

    Traditional approaches to management control usually fail for public and not-for-profit activities. The type of control applicable to such activities depends on four criteria: are objectives unambiguous, outputs measurable, effects of interventions known, and is the activity repetitive? Depending on where activities stand with regard to these criteria, the control applicable corresponds to one of six different types: routine, expert, trial-and-error, intuitive, judgemental, or political contr...

  7. Paediatric pelvic imaging: optimisation of dose and technique using digital grid-controlled pulsed fluoroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Waugh, R.; McCarty, M. [Div. of Radiology, South Cleveland Hospital, South Tees Acute Hospitals NHS Trust, Marton Road, Middlesbrough, Cleveland (United Kingdom); McCallum, H.M. [Regional Medical Physics Dept., South Cleveland Hospital, Middlesbrough (United Kingdom); Montgomery, R. [Dept. of Orthopaedics, South Tees Hospitals NITS Trust, Middlesbrough (United Kingdom); Aszkenasy, M. [Tees and North East Yorkshire NHS Trust, West Lane Hospital, Middlesbrough (United Kingdom)

    2001-05-01

    Background. An audit of paediatric pelvic radiographs identified deficiencies in gonad shield placement and radiographic technique. Objective. A technique using grid-controlled fluoroscopy (GCF), with hard copy images in frame grab and digital spot image (DSI) format was evaluated to optimise gonad shield placement and reduce the dose given to children with Perthes disease and Developmental Hip Dysplasia (DDH) attending for pelvic radiography. Materials and methods. Phantom and patient dose surveys of conventional and fluoroscopic techniques were carried out. Image quality and radiation dose were compared for the frame grab and DSI techniques. Retrospective evaluation was undertaken to compare their clinical acceptability. Results. Both fluoroscopic techniques gave considerably less radiation than conventional non-grid radiography (67-83 %, P < 0.05). The frame grab technique gave less radiation than DSI (P < 0.05). There was no significant difference in the clinical acceptability scores of the DSI and frame grab images. Conclusion. Fluoroscopy acquired images are now used since the fluoroscopic techniques give much less dose than conventional radiography and provide images of sufficient quality for clinical assessment. Indeed, as there was no significant difference in clinical usefulness between the frame grab and DSI techniques, it is planned to use frame grab alone, thus gaining additional dose saving. (orig.)

  8. Application of Artificial Intelligence Techniques for the Control of the Asynchronous Machine

    Directory of Open Access Journals (Sweden)

    F. Khammar

    2016-01-01

    Full Text Available The induction machine is experiencing a growing success for two decades by gradually replacing the DC machines and synchronous in many industrial applications. This paper is devoted to the study of advanced methods applied to the command of the asynchronous machine in order to obtain a system of control of high performance. While the criteria for response time, overtaking, and static error can be assured by the techniques of conventional control, the criterion of robustness remains a challenge for researchers. This criterion can be satisfied only by applying advanced techniques of command. After mathematical modeling of the asynchronous machine, it defines the control strategies based on the orientation of the rotor flux. The results of the different simulation tests highlight the properties of robustness of algorithms proposed and suggested to compare the different control strategies.

  9. DSP Control of Line Hybrid Active Filter

    DEFF Research Database (Denmark)

    Dan, Stan George; Benjamin, Doniga Daniel; Magureanu, R.;

    2005-01-01

    Active Power Filters have been intensively explored in the past decade. Hybrid active filters inherit the efficiency of passive filters and the improved performance of active filters, and thus constitute a viable improved approach for harmonic compensation. In this paper a parallel hybrid filter...... is studied for current harmonic compensation. The hybrid filter is formed by a single tuned Le filter and a small-rated power active filter, which are directly connected in series without any matching transformer. Thus the required rating of the active filter is much smaller than a conventional standalone...

  10. Modelling sterile insect technique to control the population of Anopheles gambiae

    OpenAIRE

    James E. Gentile; Rund, Samuel SC; Gregory R. Madey

    2015-01-01

    Background There is a renewed effort to develop novel malaria control strategies as even well-implemented existing malaria control tools may fail to block transmission in some regions. Currently, transgenic implementations of the sterile insect technique (SIT) such as the release of insects with a dominant lethal, homing endonuclease genes, or flightless mosquitoes are in development. These implementations involve the release of transgenic male mosquitoes whose matings with wild females produ...

  11. The sterile insect technique and its role in integrated Trypanosomiasis control programmes

    International Nuclear Information System (INIS)

    In the paper an attempt is made to define the rationale for using the sterile insect technique (SIT) for tsetse fly eradication within the global concept of trypanosomiasis control. Against the background of past and present research and development, and particularly the success of integrated tsetse fly control campaigns in Burkina Faso and Nigeria, the paper identifies problems to be overcome before further major action programmes with an SIT component are undertaken. (author). 33 refs

  12. Controller design for flexible, distributed parameter mechanical arms via combined state space and frequency domain techniques

    Science.gov (United States)

    Book, W. J.; Majett, M.

    1982-01-01

    The potential benefits of the ability to control more flexible mechanical arms are discussed. A justification is made in terms of speed of movement. A new controller design procedure is then developed to provide this capability. It uses both a frequency domain representation and a state variable representation of the arm model. The frequency domain model is used to update the modal state variable model to insure decoupled states. The technique is applied to a simple example with encouraging results.

  13. Brief Group Intervention Using Emotional Freedom Techniques for Depression in College Students: A Randomized Controlled Trial

    OpenAIRE

    Dawson Church; De Asis, Midanelle A.; Brooks, Audrey J.

    2012-01-01

    Two hundred thirty-eight first-year college students were assessed using the Beck Depression Inventory (BDI). Thirty students meeting the BDI criteria for moderate to severe depression were randomly assigned to either a treatment or control group. The treatment group received four 90-minute group sessions of EFT (Emotional Freedom Techniques), a novel treatment that combines exposure, cognitive reprocessing, and somatic stimulation. The control group received no treatment. Posttests were cond...

  14. Survey of Active Structural Control and Repair Using Piezoelectric Patches

    Directory of Open Access Journals (Sweden)

    Ahmed Abuzaid

    2015-05-01

    Full Text Available The piezoelectric actuator has gained popularity over the last few years. Attention has been directed towards the study of their electromechanical response in active repair and the control of damaged structures. This has been made possible through the development of various numerical and analytical techniques for such studies. The shift of focus towards the piezoelectric based approaches has been due to their advantages, which include strategic cost benefits in maintenance, as well as an increase in the life cycle of the repaired structures. Furthermore, adhesively bonded joints are widely used in the manufacturing and repairing of structures in many industries, especially automotive and aerospace engineering. This is due to the requirement for lightweight materials as well as the potential adhesive used to join materials with different characteristics. The piezoelectric actuator has also shown the capacity in controlling and lowering the shear stress concentration and joint edge peel in adhesively bonded joint systems. The structure’s control of stress and repair can generally be viewed as a reinforcement that influences the structure’s damage tolerance. Therefore, the interest of this review is on the applications of the piezoelectric actuators in both structural damage and the bonded adhesive joint system. The specific goal is to recognize the contemporary scientific challenges, including future opportunities.

  15. Active vibration control of spatial flexible multibody systems

    Energy Technology Data Exchange (ETDEWEB)

    Neto, Maria Augusta, E-mail: augusta.neto@dem.uc.pt [Universidade de Coimbra (Polo II), Departamento de Engenharia Mecanica, Faculdade de Ciencia e Tecnologia (Portugal); Ambrosio, Jorge A. C., E-mail: jorge@dem.ist.utl.pt [Instituto Superior Tecnico, Instituto de Engenharia Mecanica (Portugal); Roseiro, Luis M., E-mail: lroseiro@isec.pt [Instituto Superior de Engenharia de Coimbra, Departamento de Engenharia Mecanica (Portugal); Amaro, A., E-mail: ana.amaro@dem.uc.pt [Universidade de Coimbra (Polo II), Departamento de Engenharia Mecanica, Faculdade de Ciencia e Tecnologia (Portugal); Vasques, C. M. A., E-mail: cvasques@inegi.up.pt [Universidade do Porto, INEGI-Instituto de Engenharia Mecanica e Gestao Industrial (Portugal)

    2013-06-15

    In this work a flexible multibody dynamics formulation of complex models including elastic components made of composite materials is extended to include piezoelectric sensors and actuators. The only limitation for the deformation of a structural member is that they must remain elastic and linear when described in a coordinate frame fixed to a material point or region of its domain. The flexible finite-element model of each flexible body is obtained referring the flexible body nodal coordinates to the body fixed frame and using a diagonalized mass description of the inertia in the mass matrix and on the gyroscopic force vector. The modal superposition technique is used to reduce the number of generalized coordinates to a reasonable dimension for complex shaped structural models of flexible bodies. The active vibration control of the flexible multibody components is implemented using an asymmetric collocated piezoelectric sensor/actuator pair. An electromechanically coupled model is taken into account to properly consider the surface-bonded piezoelectric transducers and their effects on the time and spatial response of the flexible multibody components. The electromechanical effects are introduced in the flexible multibody equations of motion by the use of beam and plate/shell elements, developed to this purpose. A comparative study between the classical control strategies, constant gain and amplitude velocity feedback, and optimal control strategy, linear quadratic regulator (LQR), is performed in order to investigate their effectiveness to suppress vibrations in structures with piezoelectric sensing and actuating patches.

  16. Active Damping Techniques for LCL-Filtered Inverters-Based Microgrids

    DEFF Research Database (Denmark)

    Lorzadeh, Iman; Firoozabadi, Mehdi Savaghebi; Askarian Abyaneh, Hossein;

    2015-01-01

    LCL-type filters are widely used in gridconnected voltage source inverters, since it provides switching ripples reduction with lower cost and weight than the L-type counterpart. However, the inclusion of LCL-filters in voltage source inverters complicates the current control design regarding syst...... the different active damping approaches for grid-connected inverters with LCL filters, which are based on high-order filters and additional feedbacks methods. These techniques are analyzed and discussed in detail.......LCL-type filters are widely used in gridconnected voltage source inverters, since it provides switching ripples reduction with lower cost and weight than the L-type counterpart. However, the inclusion of LCL-filters in voltage source inverters complicates the current control design regarding system...... stability issues; because an inherent resonance peak appears due to zero impedance at that resonance frequency. Moreover, in grid-interactive low-voltage microgrids, the interactions among the LCL-filtered-based parallel inverters may result in a more complex multiresonance issue which may compromise...

  17. Behaviour based Mobile Robot Navigation Technique using AI System: Experimental Investigation on Active Media Pioneer Robot

    Directory of Open Access Journals (Sweden)

    S. Parasuraman, V.Ganapathy

    2012-10-01

    Full Text Available A key issue in the research of an autonomous robot is the design and development of the navigation technique that enables the robot to navigate in a real world environment. In this research, the issues investigated and methodologies established include (a Designing of the individual behavior and behavior rule selection using Alpha level fuzzy logic system  (b Designing of the controller, which maps the sensors input to the motor output through model based Fuzzy Logic Inference System and (c Formulation of the decision-making process by using Alpha-level fuzzy logic system. The proposed method is applied to Active Media Pioneer Robot and the results are discussed and compared with most accepted methods. This approach provides a formal methodology for representing and implementing the human expert heuristic knowledge and perception-based action in mobile robot navigation. In this approach, the operational strategies of the human expert driver are transferred via fuzzy logic to the robot navigation in the form of a set of simple conditional statements composed of linguistic variables.Keywards: Mobile robot, behavior based control, fuzzy logic, alpha level fuzzy logic, obstacle avoidance behavior and goal seek behavior

  18. Characterization of controlled bone defects using 2D and 3D ultrasound imaging techniques

    Energy Technology Data Exchange (ETDEWEB)

    Parmar, Biren J; Longsine, Whitney; Han, Arum; Righetti, Raffaella [Department of Electrical and Computer Engineering, Dwight Look College of Engineering, Texas A and M University, College Station, TX (United States); Sabonghy, Eric P [OneOrtho Orthopedic Surgery Clinic, Houston, TX (United States); Tasciotti, Ennio; Ferrari, Mauro [Department of Nanomedicine and Biomedical Engineering, University of Texas Health Science Center at Houston, Houston, TX (United States); Weiner, Bradley K, E-mail: righetti@ece.tamu.ed [Division of Spinal Surgery, Department of Orthopaedic Surgery, Methodist Hospital, Houston, TX 77030 (United States)

    2010-08-21

    Ultrasound is emerging as an attractive alternative modality to standard x-ray and CT methods for bone assessment applications. As of today, however, there is a lack of systematic studies that investigate the performance of diagnostic ultrasound techniques in bone imaging applications. This study aims at understanding the performance limitations of new ultrasound techniques for imaging bones in controlled experiments in vitro. Experiments are performed on samples of mammalian and non-mammalian bones with controlled defects with size ranging from 400 {mu}m to 5 mm. Ultrasound findings are statistically compared with those obtained from the same samples using standard x-ray imaging modalities and optical microscopy. The results of this study demonstrate that it is feasible to use diagnostic ultrasound imaging techniques to assess sub-millimeter bone defects in real time and with high accuracy and precision. These results also demonstrate that ultrasound imaging techniques perform comparably better than x-ray imaging and optical imaging methods, in the assessment of a wide range of controlled defects both in mammalian and non-mammalian bones. In the future, ultrasound imaging techniques might provide a cost-effective, real-time, safe and portable diagnostic tool for bone imaging applications.

  19. Simulation Study on Active Noise Control for a 4 Tesla MRI Scanner

    Science.gov (United States)

    Li, Mingfeng; Lim, Teik C.; Lee, Jing-Huei

    2008-01-01

    The purpose of this work is to study computationally the possibility of the application of a hybrid active noise control technique for MRI acoustic noise reduction. A hybrid control system combined with both feedforward and feedback loops embedded is proposed for potential application on active MRI noise reduction. A set of computational simulation studies were performed. Sets of MRI acoustic noise emissions measured at the patient's left ear location were recorded and used in the simulation study. By comparing three different control systems, namely the feedback, the feedforward and the hybrid control, our results revealed that the hybrid control system is the most effective. The hybrid control system achieved approximately a 20 dB reduction at the principal frequency component. We concluded that the proposed hybrid active control scheme could have a potential application for MRI scanner noise reduction. PMID:18060719

  20. A Gradient-Type Optimization Technique for the Optimal Control for Schrodinger Equations

    OpenAIRE

    M Farag

    2003-01-01

    In this paper, we are considered with the optimal control of a schrodinger equation. Based on the formulation for the variation of the cost functional, a gradient-type optimization technique utilizing the finite difference method is then developed to solve the constrained optimization problem. Finally, a numerical example is given and the results show that the method of solution is robust.

  1. Application of an active controller for reducing small-amplitude vertical vibration in a vehicle seat

    Science.gov (United States)

    Wu, Jian-Da; Chen, Rong-Jun

    2004-07-01

    This report describes the principle and application of active vibration control (AVC) for reducing undesired small-amplitude vertical vibration in the driver's seat of a vehicle. Three different control algorithms are implemented and compared in the experimental investigation. Apart from adaptive control and robust control, a hybrid control algorithm consisting of a combination of an adaptive controller with a filtered-x least mean squares (FXLMS) algorithm and a feedback structure with a robust synthesis theory for obtaining fast convergence and robust performance are proposed. A frequency domain technique is used for achieving the control plant identification and controller design. All of the proposed AVC controllers are implemented in a digital signal processor (DSP) platform, using a finite impulse response (FIR) filter for real-time control. A characteristic analysis and experimental comparison of three control algorithms for reducing the small amplitude vertical vibration in a vehicle seat are also presented in this paper.

  2. Integral Sliding Mode Control for Helicopter via Disturbance Observer and Quantum Information Technique

    Directory of Open Access Journals (Sweden)

    Qiang Qu

    2015-01-01

    Full Text Available A novel self-repairing control scheme is proposed for a helicopter with unknown disturbance. Firstly, a disturbance observer is introduced to observe the disturbance of the system, which can produce corresponding control signals according to the disturbance signals. Secondly, an integral sliding mode controller is designed to compensate the unobserved disturbance and uncertainties. All of the closed-loop poles can be arbitrarily placed and the output errors converge to zero effectively through the controller. Besides, a robust closed-loop system against disturbance and parameter uncertainties is achieved. In addition, quantum information technique is used to increase the self-repairing control accuracy of helicopter. Finally, simulation results demonstrate the effectiveness and feasibility of the proposed self-repairing control scheme.

  3. Study and development of advanced control techniques for nuclear reactors and robots

    Energy Technology Data Exchange (ETDEWEB)

    March-Leuba, C.

    1989-08-01

    This report studies and develops some aspects of the optimal control theory with the objective of evaluating benefits that the nuclear industry could obtain by applying advanced control techniques. First, the basic relationship between optimal control theory and closed-loop control design has been identified. As a result of this work, new algorithms have been developed for feedback implementations. The applicability of these new algorithms to problems such as state estimation, filtering, model update, and model decoupling has been studied. In addition, new alternatives to control design that are not based on optimal control theory have been developed. A broad range of application examples has been presented for several physical systems, including pressurized water nuclear reactors, boiling water nuclear reactors, steam generators, and robotics. 22 refs., 26 figs.

  4. Design of Critical Control Systems for Non-Minimum Phase Plants via LTR Technique

    Science.gov (United States)

    Ishihara, Tadashi; Ono, Takahiko

    An application of the loop transfer recovery (LTR) technique to critical control systems design is proposed for non-minimum phase plants. The controller structure is chosen as the Davison type integral controller with the Kalman filter. First, a critical control system is designed on the assumption that the state of the minimum phase part of the plant can be used for the feedback. A quadratic performance index with tuning parameters is used for determining the partial state feedback gain matrix. Second, the Kalman filter gain matrix is determined such that the output feedback controller performs as in the partial state feedback controller. The formal partial loop recovery procedure using the Riccati equation is adopted for this purpose. The proposed design method requires much simpler numerical search than the conventional one-step approach. An illustrative design example is presented.

  5. Study and development of advanced control techniques for nuclear reactors and robots

    International Nuclear Information System (INIS)

    This report studies and develops some aspects of the optimal control theory with the objective of evaluating benefits that the nuclear industry could obtain by applying advanced control techniques. First, the basic relationship between optimal control theory and closed-loop control design has been identified. As a result of this work, new algorithms have been developed for feedback implementations. The applicability of these new algorithms to problems such as state estimation, filtering, model update, and model decoupling has been studied. In addition, new alternatives to control design that are not based on optimal control theory have been developed. A broad range of application examples has been presented for several physical systems, including pressurized water nuclear reactors, boiling water nuclear reactors, steam generators, and robotics. 22 refs., 26 figs

  6. Site-controlled quantum dots fabricated using an atomic-force microscope assisted technique

    Directory of Open Access Journals (Sweden)

    Sakuma Y

    2006-01-01

    Full Text Available AbstractAn atomic-force microscope assisted technique is developed to control the position and size of self-assembled semiconductor quantum dots (QDs. Presently, the site precision is as good as ± 1.5 nm and the size fluctuation is within ± 5% with the minimum controllable lateral diameter of 20 nm. With the ability of producing tightly packed and differently sized QDs, sophisticated QD arrays can be controllably fabricated for the application in quantum computing. The optical quality of such site-controlled QDs is found comparable to some conventionally self-assembled semiconductor QDs. The single dot photoluminescence of site-controlled InAs/InP QDs is studied in detail, presenting the prospect to utilize them in quantum communication as precisely controlled single photon emitters working at telecommunication bands.

  7. Active control design of modular tensegrity structures

    OpenAIRE

    Amouri, Sarah; Averseng, Julien; Dubé, Jean-François

    2013-01-01

    In this paper, a general methodology for the design of modular active tensegrity structures is presented. The objectives are to propose systems such as grids or footbridges that would be able to actively damper their first vibration modes and to adapt their geometry using a small number of activators. This approach is validated experimentally on a plane regular tensegrity grid. Using numerical simulation, an application on the model of a modular tensegrity footbridge is presented.

  8. Tuning of active vibration controllers for ACTEX by genetic algorithm

    Science.gov (United States)

    Kwak, Moon K.; Denoyer, Keith K.

    1999-06-01

    This paper is concerned with the optimal tuning of digitally programmable analog controllers on the ACTEX-1 smart structures flight experiment. The programmable controllers for each channel include a third order Strain Rate Feedback (SRF) controller, a fifth order SRF controller, a second order Positive Position Feedback (PPF) controller, and a fourth order PPF controller. Optimal manual tuning of several control parameters can be a difficult task even though the closed-loop control characteristics of each controller are well known. Hence, the automatic tuning of individual control parameters using Genetic Algorithms is proposed in this paper. The optimal control parameters of each control law are obtained by imposing a constraint on the closed-loop frequency response functions using the ACTEX mathematical model. The tuned control parameters are then uploaded to the ACTEX electronic control electronics and experiments on the active vibration control are carried out in space. The experimental results on ACTEX will be presented.

  9. Traveling through potential energy surfaces of disordered materials: the activation-relaxation technique

    NARCIS (Netherlands)

    Mousseau, N.; Barkema, G.T.

    1998-01-01

    A detailed description of the activation-relaxation technique (ART) is presented. This method defines events in the configurational energy landscape of disordered materials such as amorphous semiconductors, glasses and polymers, in a two-step process: first, a configuration is activated from a local

  10. Applying Modern Techniques and Carrying Out English .Extracurricular—— On the Model United Nations Activity

    Institute of Scientific and Technical Information of China (English)

    XuXiaoyu; WangJian

    2004-01-01

    This paper is an introduction of the extracurricular activity of the Model United Nations in Northwestern Polyteehnical University (NPU) and it focuses on the application of the modem techniques in the activity and the pedagogical theories applied in it. An interview and questionnaire research will reveal the influence of the Model United Nations.

  11. Analysis of voltage modulation based active damping techniques for small DC-link drive system

    DEFF Research Database (Denmark)

    Wang, Dong; Lu, Kaiyuan; Rasmussen, Peter Omand;

    2015-01-01

    . Therefore, active damping techniques are usually needed in order to stabilize the system. This paper firstly describes the essential idea of active damping methods from energy flow point of view. Then a new method named as “virtual positive impedance” method is introduced to ensure the dc-link stability...

  12. Teaching Tip: Using Activity Diagrams to Model Systems Analysis Techniques: Teaching What We Preach

    Science.gov (United States)

    Lending, Diane; May, Jeffrey

    2013-01-01

    Activity diagrams are used in Systems Analysis and Design classes as a visual tool to model the business processes of "as-is" and "to-be" systems. This paper presents the idea of using these same activity diagrams in the classroom to model the actual processes (practices and techniques) of Systems Analysis and Design. This tip…

  13. Reconstructing muscle activation during normal walking: a comparison of symbolic and connectionist machine learning techniques

    NARCIS (Netherlands)

    Heller, Ben W.; Veltink, Peter H.; Rijkhoff, Nico J.M.; Rutten, Wim L.C.; Andrews, Brian J.

    1993-01-01

    One symbolic (rule-based inductive learning) and one connectionist (neural network) machine learning technique were used to reconstruct muscle activation patterns from kinematic data measured during normal human walking at several speeds. The activation patterns (or desired outputs) consisted of sur

  14. Active Load Control Using a Non-traditional MEMs Approach

    Science.gov (United States)

    Yen Nakafuji, Dora; van Dam, Cornelis

    2001-11-01

    An active load control concept using micro-electro-mechanical (MEM) translational tabs has been undergoing testing and development at the University of California at Davis. The concept utilizes microfabricated sliding components to retract and extend small tabs located near the trailing edge of a lifting surface. The tab assembly, referred to as a microtab, extends approximately normal to the surface and has a maximum deployment height on the order of the boundary-layer thickness. Deployment of these retractable devices on either the suction or pressure side of a lifting surface effectively modifies the camber distribution and changes the lift and moments generated. On the pressure side, the effect of the microtabs on lift is shown to be as powerful as conventional flap-like control surfaces resulting in positive DCl changes of 30conventional control surfaces which typically occupy 20of the lifting surface, these large-scale load changes are achieved using microtabs with heights of 1located 5suction side, these microtabs work by decreasing the lift resulting in negative DCl changes in the linear range of the lift curve. Numerical and experimental wind tunnel results are in good agreement, and both confirm that these micro-scale devices are capable of generating macro-scale changes in the aerodynamic loading. Application of this rather simple but innovative load control system based on microfabrication techniques will allow for miniaturization of conventional systems. With further development and integration with an activation and feedback network, these microtabs may result in significant reductions in typical control system weight, complexity and cost. Due to their minute size, the activation and response times are expected to be much faster than that of conventional trailing edge devices. Using a multi-disciplinary approach incorporating aspects of experimental and computational aerodynamics, mechanical design and microfabrication, the potentials of this concept

  15. Quantitation of microbicidal activity of mononuclear phagocytes: an in vitro technique.

    OpenAIRE

    Rege N; Dahanukar S

    1993-01-01

    An in vitro assay technique was set up to determine the phagocytic and microbicidal activity of a monocyte-macrophage cell line using Candida species as test organisms. The norms were determined for the activity of peritoneal macrophages of rats (24.69 +/- 2.6% phagocytosis and 35.4 +/- 5.22% ICK) and human (27.89 +/- 3.63% phagocytosis and 50.91 +/- 6.3% ICK). The assay technique was used to test the degree of activation of macrophages ...

  16. Application of High Order X-LMS Filter for Active Noise Control

    Directory of Open Access Journals (Sweden)

    N.V.K.Mahalakshmi

    2014-06-01

    Full Text Available In this paper active noise is controlled by using higher order X-LMS (least mean square filter. This technique is based on X-NLMS (normalized least mean square, also known as traditional acoustic noise cancellation (ANC scheme. It cancels the wideband noise from the corrupted speech signal. The active noise reducing headphone is probably the most successful application of active control of sound – the technology of cancelling sound with sound i.e., by using anti-noise signal. This report presents an outlined technical review of noise cancellation in headphones. The principles of passive noise attenuation are presented after which active attenuation is introduced showing how the two complement the attenuation performance. In real-time environment, the number of different applications in which adaptive techniques are being successfully used that are echo cancellation, equalization of dispersive channels, system identification, signal enhancement, noise cancelling and control.

  17. Design and Implementation of Prosthetic Arm using Gear Motor Control Technique with Appropriate Testing

    CERN Document Server

    Neogi, Biswarup; Ghosal, Soumya; Das, Achintya; Tibarewala, D N

    2011-01-01

    Any part of the human body replication procedure commences the prosthetic control science. This paper highlights the hardware design technique of a prosthetic arm with implementation of gear motor control aspect. The prosthetic control arm movement has been demonstrated in this paper applying processor programming and with the successful testing of the designed prosthetic model. The architectural design of the prosthetic arm here has been replaced by lighter material instead of heavy metal, as well as the traditional EMG (electro myographic) signal has been replaced by the muscle strain.

  18. Development of Novel Smart Home System based on ZigBee Technique and Embedded Control System

    Institute of Scientific and Technical Information of China (English)

    Wang Lihong

    2015-01-01

    In this paper, we report the development of novel smart home system based on ZigBee technique and embedded control system. In a lot of ZigBee technology applied in smart home system at the same time, how to view of the existing network terminal equipment, control and management of household field research also in rapid development. Terminal equipment mainly includes joining the network and control commands to send coordinator system combines the environment parameter data acquisition and serial port communication, and other functions. The simulation directly shows the effectiveness of our system visually and numerically.

  19. Phase and gain control policies for robust active vibration control of flexible structures

    OpenAIRE

    Zhang, Kai; Scorletti, Gérard; Ichchou, Mohamed; Mieyeville, F.

    2013-01-01

    The interest of this paper is to develop a general and systematic robust control methodology for active vibration control of flexible structures. For this purpose, first phase and gain control policies are proposed to impose qualitative frequency-dependent requirements on the controller to consider a complete set of control objectives. Then the proposed control methodology is developed by employing phase and gain control policies in the dynamic output feedback H∞ control: according to the set...

  20. Nonlinear Predictive Control of Semi-Active Landing Gear System

    OpenAIRE

    Wu, Dongsu; Gu, Hongbin; Liu, Hui

    2010-01-01

    The application of model predictive control and constructive nonlinear control methodology to semi-active landing gear system is studied in this paper. A unified shock absorber mathematical model incorporates solenoid valve’s electromechanical and magnetic dynamics is built to facilitate simulation and controller design. Then we propose a hierarchical control structure to deal with the high nonlinearity. A dual mode model predictive controller as an outer loop controller is developed to gen...

  1. Structural Acoustic Characteristics of Aircraft and Active Control of Interior Noise

    Science.gov (United States)

    Fuller, C. R.

    1998-01-01

    The reduction of aircraft cabin sound levels to acceptable values still remains a topic of much research. The use of conventional passive approaches has been extensively studied and implemented. However performance limits of these techniques have been reached. In this project, new techniques for understanding the structural acoustic behavior of aircraft fuselages and the use of this knowledge in developing advanced new control approaches are investigated. A central feature of the project is the Aircraft Fuselage Test Facility at Va Tech which is based around a full scale Cessna Citation III fuselage. The work is divided into two main parts; the first part investigates the use of an inverse technique for identifying dominant fuselage vibrations. The second part studies the development and implementation of active and active-passive techniques for controlling aircraft interior noise.

  2. Active vibration and noise control by hybrid active acoustic panels

    Energy Technology Data Exchange (ETDEWEB)

    Stoebener, U.; Gaul, L. [Stuttgart Univ. (Germany). Inst. A fuer Mechanik

    2001-07-01

    In the present paper a hybrid passive and active treatment for vibration and noise reduction of plate type structures is proposed. The treatment is manufactured as sandwich structure and is called hybrid active acoustic panel. The passive component is used to reduce the vibration and sound radiation for high frequencies whereas the active part of the system is designed for the low frequency range. By selecting the thickness of the passive damping layer a certain frequency limit is defined, which divides the high and low frequency range. The actuator and sensor layout of the active component is evaluated by using the mode shapes of the low frequency range. According to the evaluated layout a hybrid active acoustic panel is manufactured and experimentally tested. The experimental results validate the proposed concept. (orig.)

  3. Modern techniques for the emissions control in thermal electric stations; Tecnicas modernas para el control de emisiones en centrales termoelectricas

    Energy Technology Data Exchange (ETDEWEB)

    Romo Millares, C. A. [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1995-12-31

    This paper presents the techniques and the control equipment for emissions in thermal stations that have the highest possibilities of being considered in the immediate future in the national energy panorama and the established frame for the environmental normativity. The pollutant compounds subject to revision are the nitrogen and sulfur oxides and unburned particles. [Espanol] Se presentan las tecnicas y equipos de control de emisiones para centrales termoelectricas que tienen mayores posibilidades de ser consideradas en el futuro inmediato dentro del panorama energetico nacional y el marco establecido por la normatividad ambiental. Los compuestos contaminantes sujetos a revision son los oxidos de nitrogeno y azufre y las particulas inquemadas.

  4. Microstructure control techniques in primary hot working of titanium alloy bars: A review

    Directory of Open Access Journals (Sweden)

    Guo Lianggang

    2016-02-01

    Full Text Available How to control the microstructure of titanium alloy bars is important to fabricating high-performance aerial forgings. This paper gives a thorough survey of the manufacturing methods and microstructure control techniques for titanium alloy bars. It summarizes the effects of processing parameters on the mechanisms and laws of microstructure evolution during β working and (α + β working, including the kinetics and grains size of dynamic recrystallization (DRX during β deformation and the kinetics and grains size of spheroidization during (α + β deformation. The trends in microstructure control techniques are presented for fabricating titanium alloy bars with high efficiency, low cost, and high quality by means of β/(α + β working, and the puzzles and challenges in the future are also pointed out.

  5. Microstructure control techniques in primary hot working of titanium alloy bars:A review

    Institute of Scientific and Technical Information of China (English)

    Guo Lianggang; Fan Xiaoguang; Yu Gaofeng; Yang He

    2016-01-01

    How to control the microstructure of titanium alloy bars is important to fabricating high-performance aerial forgings. This paper gives a thorough survey of the manufacturing meth-ods and microstructure control techniques for titanium alloy bars. It summarizes the effects of pro-cessing parameters on the mechanisms and laws of microstructure evolution during b working and (a+b) working, including the kinetics and grains size of dynamic recrystallization (DRX) during b deformation and the kinetics and grains size of spheroidization during (a+b) deformation. The trends in microstructure control techniques are presented for fabricating titanium alloy bars with high efficiency, low cost, and high quality by means of b/(a+b) working, and the puzzles and chal-lenges in the future are also pointed out.

  6. Study of Controlling Acute Hemorrhage from Esophageal Varices Rupture with Technique of Traditional Chinese Medicine

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To find a method for inducing Chinese drugs to adhere to the esophageal mucosa to control bleeding from ruptured esophageal varices. Methods: The site and time that the Chinese drugs adhere to esophageal mucosa were observed in 30 healthy volunteers under the specific condition of standing and lying posture. Seventy episodes bled with ruptured esophageal varices patients (treated group 36 episodes in 25 patients and control group 34 episodes in 27 patients) suffering from cirrhosis of liver were treated by the technique of drug adhesion. Results: (1) The adhesion of Chinese hemostatic drugs remained in the lower segment of esophagus for more than 15 minutes in lying posture, longer than that in standing posture (P0.05). Conclusion: This drug adhesion technique provides a new approach to control hemorrhage from ruptured esophageal varices.

  7. Short Horizon Control Strategies for an Alternating Activated Sludge Process

    DEFF Research Database (Denmark)

    Isaacs, Steven Howard

    1996-01-01

    Three control strategies allowing improved operational flexibility of an alternating type activated sludge process are presented in a unified model based framework. The control handles employed are the addition rate of an external carbon source to denitrification, the cycle length...

  8. A new flow control technique for handling infinitesimal flows inside a Lab-On-a-Chip

    International Nuclear Information System (INIS)

    A syringe pump or a device using high electric voltage has been used for controlling flows inside a LOC (Lab-On-a-Chip). Compared to LOC, however, these microfluidic devices are large and heavy that they are burdensome for a portable μ-TAS (micro Total Analysis System). In this study, a new flow control technique employing pressure regulators and pressure chambers was developed. This technique utilizes compressed air to control the micro-scale flow inside a LOC, instead of a mechanical actuator or an electric power supply. The pressure regulator controls the output air pressure by adjusting the variable resistor attached. We checked the feasibility of this system by measuring the flow rate inside a capillary tube of 100μm diameter in the Re numbers ranged from 0.5 to 50. In addition, the performance of this flow control system was compared with that of a conventional syringe pump. The developed flow control system was found to show superior performance, compared with the syringe pump. It maintains automatically the air pressure inside a pressure chamber whether the flow inside the capillary tube is on or off. Since the flow rate is nearly proportional to the resistance, we can control flow in multiple microchannels precisely. However, the syringe pump shows large variation of flow rate when the fluid flow is blocked in the microchannel

  9. Hip Labral Reconstruction: The "Kite Technique" for Improved Efficiency and Graft Control.

    Science.gov (United States)

    Bhatia, Sanjeev; Chahla, Jorge; Dean, Chase S; Ellman, Michael B

    2016-04-01

    Although the merits of labral reconstruction have been well established, the technical difficulty of presently used reconstruction techniques-particularly with graft passage and fixation-limit its efficacy and potentiates the risk of iatrogenic damage within the hip joint. The unwieldy nature of a floating labral graft anchored on one end may impede accurate fixation of the other end, which is critical for restoration of the fluid hip seal and preservation of graft integrity. In this technique narrative, we present a "kite technique" for introduction, control, and efficient fixation of a labral reconstruction graft. The principles of this method are founded on the belief that a soft-tissue graft in an arthroscopic environment is much easier to guide into position with 2 control sutures using a pulley system similar to flying a kite with 2 fly lines. Although we herein detail the technique as it applies to labral reconstruction in the hip, the concept of the kite technique may also be employed in arthroscopic-assisted soft-tissue reconstructions of other joints. PMID:27354954

  10. Brain-Activity-Driven Real-Time Music Emotive Control

    OpenAIRE

    Giraldo, Sergio; Ramirez, Rafael

    2013-01-01

    Active music listening has emerged as a study field that aims to enable listeners to interactively control music. Most of active music listening systems aim to control music aspects such as playback, equalization, browsing, and retrieval, but few of them aim to control expressive aspects of music to convey emotions. In this study our aim is to enrich the music listening experience by allowing listeners to control expressive parameters in music performances using their perceived emotional stat...

  11. Self-Tuning Active Vibration Control of Flexible Beam Structures

    OpenAIRE

    M.O. Tokhi; Hossain, M A

    1994-01-01

    This paper presents the design and performance evaluation of an adaptive active control mechanism for vibration suppression in flexible beam structures. A cantilever beam system in transverse vibration is considered. First order control finite difference methods are used to study the behaviour of the beam and develop a suitable test and verification platform. An active vibration control algorithm is developed within an adaptive control framework for broadband cancellation of vibration along t...

  12. Active and Passive Flow Control around Simplified Ground Vehicles

    Directory of Open Access Journals (Sweden)

    C.H Bruneau

    2012-01-01

    Full Text Available The aim of this work is to control the flow around ground vehicles by active or/and passive strategies. The active control is achieved by steady, pulsed or closed-loop jets located at the backof the simplified car model. The passive control is performed using porous layers between the solid body and the fluid in order to modify the shear forces. The two previous control methods can be coupled to improve the drag reduction.

  13. Cultivar Selection and Pest Control Techniques on Organic White Cabbage Yield

    Directory of Open Access Journals (Sweden)

    Vasile V. STOLERU

    2012-11-01

    Full Text Available In Romania, as in many other countries, white cabbage is one of the most important vegetable crop species. The experiment was performed in the NE of the country during 2008-2009 in order to measure the impact of cultivar choice and pest control techniques on organic white cabbage [Brassica oleracea (L. var. capitata f. alba (D.C.]. This experiment included early, summer and autumn crops. The early crop compared four cultivars, the summer crop two cultivars, and the autumn crop three cultivars. The effect of various common organic pest control techniques was also measured. These techniques included: treatments with extract from neem (Azadirachta indica, potassium soap, Bacillus thuringiensis var. kurstaki toxins, application of a parasitic wasp (Trichogramma evanescens and covering the crop with an agrotextile. Data were collected regarding the effect of cultivar selection and pest control technique on common local cabbage pests: cabbage flea beetle (Phyllotreta atra, cabbage fly (Delia brassicae, cabbage moth (Mamestra brassicae and cabbage butterfly (Pieris brassicae. The highest yields for each respective growing season were obtained using the following combinations: Flavius agrotextile (early crop, Copenhagen Market agrotextile + 4 lha-1 azadirachtin + 12104 wasps/ha (summer crop and Buzau 4 lha-1 azadirachtin (autumn crop.

  14. Power quality improvement using DPC controlled three-phase shunt active filter

    Energy Technology Data Exchange (ETDEWEB)

    Chaoui, Abdelmadjid [Laboratoire d' Automatique et d' Informatique Industrielle (LAII-ESIP), Universite de Poitiers (France); Gaubert, Jean-Paul; Krim, Fateh [Laboratoire d' Electronique de Puissance et Commande Industrielle (LEPCI), Universite de Setif (Algeria)

    2010-06-15

    This paper presents a new control method entitled direct power control (DPC) for shunt active power filter (APF), which is applied to eliminate line current harmonics and compensate reactive power. Its main goal is to rebuild active and reactive source powers to be compared to references values using hysteresis control. The active power reference is issue of DC-side of inverter and reactive power reference is set to zero for unity power factor. The outputs of hysteresis controllers associated with a switching table, control the instantaneous active and reactive power by selecting the optimum switching state of the voltage source inverter (VSI). A theoretical analysis with a complete simulation of the system and experimental results are presented to prove the excellent performance of the proposed technique. (author)

  15. Open abdomen in gastrointestinal surgery: Which technique is the best for temporary closure during damage control?

    Science.gov (United States)

    Ribeiro Junior, Marcelo A F; Barros, Emily Alves; de Carvalho, Sabrina Marques; Nascimento, Vinicius Pereira; Cruvinel Neto, José; Fonseca, Alexandre Zanchenko

    2016-01-01

    AIM To compare the 3 main techniques of temporary closure of the abdominal cavity, vacuum assisted closure (vacuum-assisted closure therapy - VAC), Bogota bag and Barker technique, in damage control surgery. METHODS After systematic review of the literature, 33 articles were selected to compare the efficiency of the three procedures. Criteria such as cost, infections, capacity of reconstruction of the abdominal wall, diseases associated with the technique, among others were analyzed. RESULTS The Bogota bag and Barker techniques present as advantage the availability of material and low cost, what is not observed in the VAC procedure. The VAC technique is the most efficient, not only because it reduces the tension on the boarders of the lesion, but also removes stagnant fluids and debris and acts at cellular level increasing cell proliferation and division. Bogota bag presents the higher rates of skin laceration and evisceration, greater need for a stent for draining fluids and wash-ups, higher rates of intestinal adhesion to the abdominal wall. The Barker technique presents lack of efficiency in closing the abdominal wall and difficulty on maintaining pressure on the dressing. The VAC dressing can generate irritation and dermatitis when the drape is applied, in addition to pain, infection and bleeding, as well as toxic shock syndrome, anaerobic sepsis and thrombosis. CONCLUSION The VAC technique, showed to be superior allowing a better control of liquid on the third space, avoiding complications such as fistula with small mortality, low infection rate, and easier capability on primary closure of the abdominal cavity. PMID:27648164

  16. Masking technique for coating thickness control on large and strongly curved aspherical optics

    OpenAIRE

    Sassolas, B; Flaminio, R; FRANC, J; Michel, C; Michel, Christine; Montorio, J.-L.; Morgado, N.; Pinard, L.

    2009-01-01

    This paper discusses a method to control the coating thickness deposited onto large and strongly curved optics by ion beam sputtering. The technique uses an original design of the mask used to screen part of the sputtered materials. A first multi-element mask is calculated from the measured 2D coating thickness distribution. Then, by means of an iterative process the final mask is designed. By using such a technique, it has been possible to deposit layers of tantalum pentoxide having a high t...

  17. Masking technique for coating thickness control on large and strongly curved aspherical optics.

    Science.gov (United States)

    Sassolas, B; Flaminio, R; Franc, J; Michel, C; Montorio, J-L; Morgado, N; Pinard, L

    2009-07-01

    We discuss a method to control the coating thickness deposited onto large and strongly curved optics by ion beam sputtering. The technique uses an original design of the mask used to screen part of the sputtered materials. A first multielement mask is calculated from the measured two-dimensional coating thickness distribution. Then, by means of an iterative process, the final mask is designed. By using such a technique, it has been possible to deposit layers of tantalum pentoxide having a high thickness gradient onto a curved substrate 500 mm in diameter. Residual errors in the coating thickness profile are below 0.7%. PMID:19571934

  18. Closed vessel technique for assessment of ballistic characteristics in quality control of propellant manufacture

    Directory of Open Access Journals (Sweden)

    G. Siva Ramakrishnan

    1958-07-01

    Full Text Available "In order to assess the ballistic performance of a propellant it is necessary to measure its following characteristics: (aForce constant, (bvivacity, and (cshape. It is possible to determine (aand (bby the closed vessel technique which enables ballistic performance of the propellant in the gun to be estimated. It can be very usefully employed for quality control of propellant manufacture. As more and more experience is gained in the closed vessel technique these tests have several other possible practical applications such as those: (afor inspection of propellants, (bfor assessment of quality, (c to reduce proof in guns, and (dto check ballistics of a lot after long storage."

  19. Investigating real-time activation of adenosine receptors by bioluminescence resonance energy transfer technique

    Science.gov (United States)

    Huang, Yimei; Yang, Hongqin; Zheng, Liqin; Chen, Jiangxu; Wang, Yuhua; Li, Hui; Xie, Shusen

    2013-02-01

    Adenosine receptors play important roles in many physiological and pathological processes, for example regulating myocardial oxygen consumption and the release of neurotransmitters. The activations of adenosine receptors have been studied by some kinds of techniques, such as western blot, immunohistochemistry, etc. However, these techniques cannot reveal the dynamical response of adenosine receptors under stimulation. In this paper, bioluminescence resonance energy transfer technique was introduced to study the real-time activation of adenosine receptors by monitoring the dynamics of cyclic adenosine monophosphate (cAMP) level. The results showed that there were significant differences between adenosine receptors on real-time responses under stimulation. Moreover, the dynamics of cAMP level demonstrated that competition between adenosine receptors existed. Taken together, our study indicates that monitoring the dynamics of cAMP level using bioluminescence resonance energy transfer technique could be one potential approach to investigate the mechanism of competitions between adenosine receptors.

  20. Performance of active vibration control technology: the ACTEX flight experiments

    Science.gov (United States)

    Nye, T. W.; Manning, R. A.; Qassim, K.

    1999-12-01

    This paper discusses the development and results of two intelligent structures space-flight experiments, each of which could affect architecture designs of future spacecraft. The first, the advanced controls technology experiment I (ACTEX I), is a variable stiffness tripod structure riding as a secondary payload on a classified spacecraft. It has been operating well past its expected life since becoming operational in 1996. Over 60 on-orbit experiments have been run on the ACTEX I flight experiment. These experiments form the basis for in-space controller design problems and for concluding lifetime/reliability data on the active control components. Transfer functions taken during the life of ACTEX I have shown consistent predictability and stability in structural behavior, including consistency with those measurements taken on the ground prior to a three year storage period and the launch event. ACTEX I can change its modal characteristics by employing its dynamic change mechanism that varies preloads in portions of its structure. Active control experiments have demonstrated maximum vibration reductions of 29 dB and 16 dB in the first two variable modes of the system, while operating over a remarkable on-orbit temperature range of -80 °C to 129 °C. The second experiment, ACTEX II, was successfully designed, ground-tested, and integrated on an experimental Department of Defense satellite prior to its loss during a launch vehicle failure in 1995. ACTEX II also had variable modal behavior by virtue of a two-axis gimbal and added challenges of structural flexibility by being a large deployable appendage. Although the loss of ACTEX II did not provide space environment experience, ground testing resulted in space qualifying the hardware and demonstrated 21 dB, 14 dB, and 8 dB reductions in amplitude of the first three primary structural modes. ACTEX II could use either active and/or passive techniques to affect vibration suppression. Both experiments trailblazed

  1. Analysis and Optimal Condition of the Rear-Sound-Aided Control Source in Active Noise Control

    Directory of Open Access Journals (Sweden)

    Karel Kreuter

    2011-01-01

    Full Text Available An active noise control scenario of simple ducts is considered. The previously suggested technique of using an single loudspeaker and its rear sound to cancel the upstream sound is further examined and compared to the bidirectional solution in order to give theoretical proof of its advantage. Firstly, a model with a new approach for taking damping effects into account is derived based on the electrical transmission line theory. By comparison with the old model, the new approach is validated, and occurring differences are discussed. Moreover, a numerical application with the consideration of damping is implemented for confirmation. The influence of the rear sound strength on the feedback-path system is investigated, and the optimal condition is determined. Finally, it is proven that the proposed source has an advantage of an extended phase lag and a time delay in the feedback-path system by both frequency-response analysis and numerical calculation of the time response.

  2. [Analysis of color gamut of LCD system based on LED backlight with area-controlling technique].

    Science.gov (United States)

    Li, Fu-Wen; Jin, Wei-Qi; Shao, Xi-Bin; Zhang, Li-Lei; Wan, Li-Fang

    2010-05-01

    Color gamut as a significant performance index for display system describes the color reproduction ability IN real scenes. Liquid crystal display (LCD) is the most popular technology in flat panel display. However, conventional cold cathode fluorescent lamp (CCFL) backlight of LCD can not behave high color gamut compared with cathode ray tube (CRT). The common used method of color gamut measuring for LCD system is introduced at the beginning. According to the inner structure and display principle of LCD system, there are three major factors deciding LCD's color gamut: spectral properties of backlight, transmittance properties of color filters and performance of liquid crystal panel. Instead of conventional backlight CCFL, RGB-LED backlight is used for improving color reproduction of LCD display system. Due to the imperfect match between RGB-LED' s spectra and color filter's transmittance, the color filter would reduce the color gamut of LCD system more or less. Therefore, LCD system based on LED backlight with area-control technique is introduced which modifies backlight control signal according to the input signal After analyzing and calculating the spectra of LED backlight which passes through the color filters using method of colorimetry, the area sizes of color gamut triangles of RGB-LED backlight with area-control and RGB-LED backlight without area-control LCD systems are compared and the relationship between color gamut and varying contrast of liquid crystal panel is analyzed. It is indicated that LED backlight with area-control technique can avoid color saturation dropping and have little effects on the contrast variation of liquid crystal panel. In other words, LED backlight with area-control technique relaxes the requirements of both color filter performance and liquid crystal panel. Thus, it is of importance to improve the color gamut of the current LCD system with area-control LED backlight.

  3. Do physical activity and dietary smartphone applications incorporate evidence-based behaviour change techniques?

    OpenAIRE

    Direito, Artur; Pfaeffli Dale, Leila; Shields, Emma; Dobson, Rosie; Whittaker, Robyn; Maddison, Ralph

    2014-01-01

    Background There has been a recent proliferation in the development of smartphone applications (apps) aimed at modifying various health behaviours. While interventions that incorporate behaviour change techniques (BCTs) have been associated with greater effectiveness, it is not clear to what extent smartphone apps incorporate such techniques. The purpose of this study was to investigate the presence of BCTs in physical activity and dietary apps and determine how reliably the taxonomy checklis...

  4. Effect of Preparation Techniques of Y-Mo/HZSM-5 on Its Activity in Methane Aromatization

    Institute of Scientific and Technical Information of China (English)

    Qiying Wang; Weiming Lin

    2004-01-01

    The production of benzene directly from methane aromatization under oxygen-free condition is currently a new focus in natural gas utilization. The influence of preparation techniques of the catalysts on their catalytic activities is studied in this paper. The influencing factors include the impregnating method, the calcination temperature, the promoter content and the acidity of the zeolite support. Optimum preparation techniques for the catalysts are obtained through this work.

  5. The Trojan Female Technique: A Novel, Effective and Humane Approach for Pest Population Control

    International Nuclear Information System (INIS)

    Full-text: Humankind's ongoing battle with pest species spans millennia. Pests cause or carry disease, damage or consume food crops and other resources, and drive global environmental change. Conventional approaches to pest management usually involve lethal control, but such approaches are costly, of varying efficiency and often have ethical issues. Thus, pest management via control of reproductive output is increasingly considered an optimal solution. One of the most successful such 'fertility control' strategies developed to date is the sterile male technique (SMT), in which large numbers of sterile males are released into a population each generation. However, this approach is time-consuming, labour- intensive and costly. We use mathematical models to test a new twist on the SMT, using maternally inherited mitochondrial (mtDNA) mutations that affect male, but not female reproductive fitness. 'Trojan females' carrying such mutations, and their female descendants, produce 'sterile-male'-equivalents under natural conditions over multiple generations. We find that the Trojan Female Technique (TFT) has the potential to be a novel humane approach for pest control. Single large releases and relatively few small repeat releases of Trojan females both provided effective and persistent control within relatively few generations. Although greatest efficacy was predicted for high-turnover species, the additive nature of multiple releases made the TFT applicable to the full range of life histories modelled. The extensive conservation of mtDNA among eukaryotes suggests this approach could have broad utility for pest control. (author)

  6. Formal Verification of Effectiveness of Control Activities in Business Processes

    Science.gov (United States)

    Arimoto, Yasuhito; Iida, Shusaku; Futatsugi, Kokichi

    It has been an important issue to deal with risks in business processes for achieving companies' goals. This paper introduces a method for applying a formal method to analysis of risks and control activities in business processes in order to evaluate control activities consistently, exhaustively, and to give us potential to have scientific discussion on the result of the evaluation. We focus on document flows in business activities and control activities and risks related to documents because documents play important roles in business. In our method, document flows including control activities are modeled and it is verified by OTS/CafeOBJ Method that risks about falsification of documents are avoided by control activities in the model. The verification is done by interaction between humans and CafeOBJ system with theorem proving, and it raises potential to discuss the result scientifically because the interaction gives us rigorous reasons why the result is derived from the verification.

  7. Active control of radiated sound using nearfield pressure sensing

    Institute of Scientific and Technical Information of China (English)

    CHEN Ke'an; YIN Xuefei

    2004-01-01

    Based on nearfield sound pressure sensing to pick up error information, an approach for constructing active acoustic structure to effectively reduce radiated sound power at low frequency is proposed. The idea is that a nearfield pressure after active control is used as error signals and transformed into an objective function in adaptive active control process.Firstly sound power expression using near-field pressure radiated from a flexible structure is derived, and then three kind of nearfield pressure based active control strategies, I.e. Minimization of radiated sound power, minimization of sound power for dominant radiation modes and minimization of sound power for modified dominant radiation modes are respectively presented and applied to active control of radiated single and broadband noise. Finally computer simulations on sound power reduction under three strategies are conducted and it is shown that the proposed active control strategies are invalid and considerable reduction in radiated sound power can be achieved.

  8. Selective Activation and Disengagement of Moral Control.

    Science.gov (United States)

    Bandura, Albert

    1990-01-01

    Analyzes psychological mechanisms by which moral control is selectively disengaged from inhumane conduct in ordinary and unusual circumstances. Explores the symptoms of moral exclusion as described in the literature. Presents categories that unify theory on moral exclusion and contribute practical classifications for use in empirical studies. (JS)

  9. Orthogonal Control of Antibacterial Activity with Light

    NARCIS (Netherlands)

    Velema, Willem A.; van der Berg, Jan Pieter; Szymanski, Wiktor; Driessen, Arnold J. M.; Feringa, Ben L.

    2014-01-01

    Selection of a single bacterial strain out of a mixture of microorganisms is of crucial importance in healthcare and microbiology research. Novel approaches that can externally control bacterial selection are a valuable addition to the microbiology toolbox. In this proof-of-concept, two complementar

  10. Broadband Radiation Modes: Estimation and Active Control

    NARCIS (Netherlands)

    Berkhoff, Arthur P.

    2002-01-01

    In this paper we give a formulation of the most efficiently radiating vibration patterns of a vibrating body, the radiation modes, in the time domain. The radiation modes can be used to arrive at efficient weighting schemes for an array of sensors in order to reduce the controller dimensionality. Be

  11. A Low Latency Electrocardiographic QRS Activity Recovery Technique for Use on the Upper Left Arm

    Directory of Open Access Journals (Sweden)

    William D. Lynn

    2014-07-01

    Full Text Available Empirical mode decomposition is used as a low latency method of recovering the cardiac ventricular activity QRS biopotential signals recorded from the upper arm. The recovery technique is tested and compared with the industry accepted technique of signal averaging using a database of “normal” rhythm traces from bipolar ECG leads along the left arm, recorded from patient volunteers at a cardiology day procedure clinic. The same partial recomposition technique is applied to recordings taken using an innovative dry electrode technology supplied by Plessey Semiconductors. In each case, signal to noise ratio (SNR is used as a metric for comparison.

  12. Study on Component Synthesis Active Vibration Suppression Method Using Zero-placement Technique

    Institute of Scientific and Technical Information of China (English)

    Zhang Jianying; Liu Tun; Zhao Zhiping

    2008-01-01

    The component synthesis active vibration suppression method (CSVS) can be applied to suppress the vibration of flexible systems.By this method, several same or similar time-varying components are arranged according to certain rules along the time axis. The synthesized command can suppress the arbitrary unwanted vibration harmonic while achieving the desired rigid body motion. The number of the components increases rapidly when the number of harmonic vibration is growing. In this article, the CSVS based on zero-placement technique is used to construct the synthesized command to suppress the multi-harmonics simultaneously in the discrete domain.The nature of zero-placement method is to put enough zeros to cancel system poles at necessary points. The designed synthesized command has equal time intervals between each component and which is much easier to be implemented. Using this method, the number of components increases linearly with the increasing of the number of being suppressed harmonics. For the spacecraft with flexible appendages, CSVS based on zero-placement is used to design the time optimal large angle maneuver control stategy. Simulations have verified the validity and superiority of the proposed approach.

  13. Spacecraft stability and control using new techniques for periodic and time-delayed systems

    Science.gov (United States)

    NAzari, Morad

    This dissertation addresses various problems in spacecraft stability and control using specialized theoretical and numerical techniques for time-periodic and time-delayed systems. First, the effects of energy dissipation are considered in the dual-spin spacecraft, where the damper masses in the platform (?) and the rotor (?) cause energy loss in the system. Floquet theory is employed to obtain stability charts for different relative spin rates of the subsystem [special characters omitted] with respect to the subsystem [special characters omitted]. Further, the stability and bifurcation of delayed feedback spin stabilization of a rigid spacecraft is investigated. The spin is stabilized about the principal axis of the intermediate moment of inertia using a simple delayed feedback control law. In particular, linear stability is analyzed via the exponential-polynomial characteristic equations and then the method of multiple scales is used to obtain the normal form of the Hopf bifurcation. Next, the dynamics of a rigid spacecraft with nonlinear delayed multi-actuator feedback control are studied, where a nonlinear feedback controller using an inverse dynamics approach is sought for the controlled system to have the desired linear delayed closed-loop dynamics (CLD). Later, three linear state feedback control strategies based on Chebyshev spectral collocation and the Lyapunov Floquet transformation (LFT) are explored for regulation control of linear periodic time delayed systems. First , a delayed feedback control law with discrete delay is implemented and the stability of the closed-loop response is investigated in the parameter space of available control gains using infinite-dimensional Floquet theory. Second, the delay differential equation (DDE) is discretized into a large set of ordinary differential equations (ODEs) using the Chebyshev spectral continuous time approximation (CSCTA) and delayed feedback with distributed delay is applied. The third strategy involves

  14. Nonlinear Economic Model Predictive Control Strategy for Active Smart Buildings

    DEFF Research Database (Denmark)

    Santos, Rui Mirra; Zong, Yi; Sousa, Joao M. C.;

    2016-01-01

    Nowadays, the development of advanced and innovative intelligent control techniques for energy management in buildings is a key issue within the smart grid topic. A nonlinear economic model predictive control (EMPC) scheme, based on the branch-and-bound tree search used as optimization algorithm...... for solving the nonconvex optimization problem is proposed in this paper. A simulation using the nonlinear model-based controller to control the temperature levels of an intelligent office building (PowerFlexHouse) is addressed. Its performance is compared with a linear model-based controller. The nonlinear...

  15. Active vibration control of a full scale aircraft wing using a reconfigurable controller

    Science.gov (United States)

    Prakash, Shashikala; Renjith Kumar, T. G.; Raja, S.; Dwarakanathan, D.; Subramani, H.; Karthikeyan, C.

    2016-01-01

    This work highlights the design of a Reconfigurable Active Vibration Control (AVC) System for aircraft structures using adaptive techniques. The AVC system with a multichannel capability is realized using Filtered-X Least Mean Square algorithm (FxLMS) on Xilinx Virtex-4 Field Programmable Gate Array (FPGA) platform in Very High Speed Integrated Circuits Hardware Description Language, (VHDL). The HDL design is made based on Finite State Machine (FSM) model with Floating point Intellectual Property (IP) cores for arithmetic operations. The use of FPGA facilitates to modify the system parameters even during runtime depending on the changes in user's requirements. The locations of the control actuators are optimized based on dynamic modal strain approach using genetic algorithm (GA). The developed system has been successfully deployed for the AVC testing of the full-scale wing of an all composite two seater transport aircraft. Several closed loop configurations like single channel and multi-channel control have been tested. The experimental results from the studies presented here are very encouraging. They demonstrate the usefulness of the system's reconfigurability for real time applications.

  16. Multichannel active noise control systems and algorithms for reduction on broadband noise

    NARCIS (Netherlands)

    Berkhoff, A.P.; Wesselink, J.M.

    2007-01-01

    Active noise contral systems for braadband noise reduction require substantial computing power, especially for multichannel systems and adaptive controllers. Furthermore, speed of convergence can be an issue as weil. In this paper, methods and techniques are described that are able to reduce the com

  17. Position and Speed Control of Brushless DC Motors Using Sensorless Techniques and Application Trends

    Directory of Open Access Journals (Sweden)

    Jaime Gómez-Gil

    2010-07-01

    Full Text Available This paper provides a technical review of position and speed sensorless methods for controlling Brushless Direct Current (BLDC motor drives, including the background analysis using sensors, limitations and advances. The performance and reliability of BLDC motor drivers have been improved because the conventional control and sensing techniques have been improved through sensorless technology. Then, in this paper sensorless advances are reviewed and recent developments in this area are introduced with their inherent advantages and drawbacks, including the analysis of practical implementation issues and applications. The study includes a deep overview of state-of-the-art back-EMF sensing methods, which includes Terminal Voltage Sensing, Third Harmonic Voltage Integration, Terminal Current Sensing, Back-EMF Integration and PWM strategies. Also, the most relevant techniques based on estimation and models are briefly analysed, such as Sliding-mode Observer, Extended Kalman Filter, Model Reference Adaptive System, Adaptive observers (Full-order and Pseudoreduced-order and Artificial Neural Networks.

  18. The use of object-oriented techniques and CORBA in astronomical instrumentation control systems

    Science.gov (United States)

    Dipper, Nigel A.; Blackburn, Colin

    2004-09-01

    Control software for astronomy matches the ever increasing complexity of new large instrumentation projects. In order to speed the development cycle, object-oriented techniques have been used to generate loosely coupled software objects and larger scale components that can be reused in future projects. Such object-oriented systems provide for short development cycles which can respond to changing requirements and allow for extension. The Unified Modeling Language (UML) has been used for the analysis, design and implementation of this software. A distributed system is supported by the use of an object broker such as CORBA. These techniques are being applied to the development of an instrument control system for the UK spectrograph within FMOS (Fiber-fed Multi-Object Spectrograph). This is a second generation instrument for the Subaru Telescope of the National Astronomical Observatory of Japan.

  19. Laboratory training manual on the use of nuclear techniques in insect research and control. 3. ed.

    International Nuclear Information System (INIS)

    Isotopes are commonly used in agricultural research in developed countries, but because of a lack of both training and equipment isotopic techniques are not frequently used in developing countries. This manual has been prepared with the aim of helping entomologists and others responsible for the control of insects in developing countries become familiar with the potential uses of isotopes and radiation in solving some of their research and insect control problems. After chapters dealing with radiation safety, the general properties of radiation and isotopes (especially those used by entomologists), and radiation detection and assay of radioactivity, two further chapters discuss applications to entomological problems and the sterile insect technique. Numerous case studies are described, and the final chapter also includes a description of eight laboratory exercises to investigate the effects of gamma irradiation and chemosterilants on insects. Refs, figs and tabs

  20. Soft Real-Time Guarantee for Control Applications Using Both Measurement and Analytical Techniques

    Directory of Open Access Journals (Sweden)

    Baek-Young Choi

    2009-11-01

    Full Text Available In this paper, we present a probabilistic admission control algorithm over switched Ethernet to support soft real-time control applications with heterogeneous periodic flows. Our approach is purely end host based, and it enables real-time application-to-application QoS management over switched Ethernet without sophisticated packet scheduling or resource reservation mechanisms in Ethernet switches or middleware on end hosts. In designing the probabilistic admission control algorithm, we employ both measurement and analytical techniques. In particular, we provide a new and efficient method to identify and estimate the queueing delay probability inside Ethernet switches for heterogeneous periodic flows with variable message size and period. We implement the probabilistic admission control algorithm on the Windows operating system, and validated its efficacy through extensive experiments.

  1. Sensorless AC electric motor control robust advanced design techniques and applications

    CERN Document Server

    Glumineau, Alain

    2015-01-01

    This monograph shows the reader how to avoid the burdens of sensor cost, reduced internal physical space, and system complexity in the control of AC motors. Many applications fields—electric vehicles, wind- and wave-energy converters and robotics, among them—will benefit. Sensorless AC Electric Motor Control describes the elimination of physical sensors and their replacement with observers, i.e., software sensors. Robustness is introduced to overcome problems associated with the unavoidable imperfection of knowledge of machine parameters—resistance, inertia, and so on—encountered in real systems. The details of a large number of speed- and/or position-sensorless ideas for different types of permanent-magnet synchronous motors and induction motors are presented along with several novel observer designs for electrical machines. Control strategies are developed using high-order, sliding-mode and quasi-continuous-sliding-mode techniques and two types of observer–controller schemes based on backstepping ...

  2. A robust damping controller for SMES using loop-shaping technique

    Energy Technology Data Exchange (ETDEWEB)

    Rahim, A.H.M.A. [King Faud Univ. of Petroleum and Minerals, Dept. of Electrical Engineering, Dhahran (Saudi Arabia); Nowicki, E.P. [Calgary Univ., Dept. of Electrical Engineering, Calgary, AB (Canada)

    2005-07-01

    A robust damping controller for a power system installed with super-conducting magnetic energy storage (SMES) has been designed using a simple graphical loop-shaping technique. The graphical method starts by selection of a nominal plant function satisfying the robust stability and performance criterion. The variations in operating conditions from the nominal values are modeled as multiplicative structured uncertainty. The generator-SMES system has been represented with a detailed dynamic model for the control design. The robust design, with generator speed variation as the controller input, was tested for a range of operating points considering various disturbances. It is observed that the fixed parameter robust controller provides very good damping for a wide range of operating conditions. (Author)

  3. Comparison study of input shaping techniques to control an underactuated flexible link system

    Science.gov (United States)

    Al Hamidi, Yasser; Rakotondrabe, Micky

    2016-05-01

    This paper compares between three different input shaping feedforward techniques, traditional (TIS), extra insensitive (EI), and modified input shaping (MIS), to reduce the vibration of a flexible link QUANSER system. The main challenge is that the system under test is an underactuated system: it has one input and two outputs. This makes the application of the input shaping techniques not utilizable directly. We therefore first propose to use a variable change at the output in order to make the process equivalent to a monovariable system without modification of the behavior and of the objective of the control. The experimental tests demonstrate the efficiency of the technique and the different results from the three control techniques are compared and discussed. It comes out that EI shapers are the most efficient in term of robustness. MIS shaper has a shorter length than that of a corresponding TIS shaper; however both shapers have the same ability of vibration suppression. Also MIS scheme is easier than the traditional scheme because the numerical optimization is unnecessary in the design of the MIS shaper. MIS shaper has an advantage over a TIS corresponding shaper in being capable of suppressing multimode of vibration.

  4. Technology transfer of nuclear techniques and nucleonic control systems in the mineral industry

    International Nuclear Information System (INIS)

    Among the many beneficial applications of radiation and radioisotopes in industry which are now well established in advanced countries, the applications of nuclear techniques and nucleonic control systems in the mineral industry have great potential for developing Member States. The use of nucleonic on-stream analyzers in the coal industry has resulted in enormous technical and economic benefits in addition to minimization of environmental pollution. Large savings have also resulted from the use of such analyzers in the processing of other minerals. Nuclear borehole logging techniques have demonstrated great potential in oil and gas evaluation. Radiotracer investigations have led to process optimisation and trouble shooting in various stages in ore processing and metallurgy. Though the technical and economic benefits of applications of nuclear techniques in the mineral industry are well recognised, technology transfer in these areas has been hampered by a variety of factors. In order to review the status and trends in nuclear techniques and nucleonic control systems in the mineral industry and the problems and considerations in their technology transfer to developing Member States, the IAEA convened an Advisory Group Meeting in Bombay, India, 15-19 January 1990. The present publication is based on the 7 contributions presented at this meeting. A separate abstract was prepared for each of these papers. Refs, figs and tabs

  5. Environmental effects of energy production and utilization in the U.S. Volume 3. Techniques for controlling emissions

    International Nuclear Information System (INIS)

    Technological, social, economic and political techniques for controlling emission are summarized for environmental pollutants introduced into air, water and land resources. Chemical, radiological and physical factors are discussed

  6. Swarming Speed Control for DC Permanent Magnet Motor Drive via Pulse Width Modulation Technique and DC/DC Converter

    Directory of Open Access Journals (Sweden)

    A.S. Oshaba

    2013-05-01

    Full Text Available This study presents an approach for the speed control of a permanent magnet DC motor drive via Pulse Width Modulation (PWM technique and a DC/DC converter. The Particle Swarm Optimization (PSO technique is used to minimize a time domain objective function and obtain the optimal controller parameters. The performance of the proposed technique has been evaluated using various types of disturbances including load torque variations. Simulation results illustrate clearly the robustness of the controller and validity of the design technique for controlling the speed of permanent magnet motors.

  7. Adaptive Neural Control of Pure-Feedback Nonlinear Time-Delay Systems via Dynamic Surface Technique.

    Science.gov (United States)

    Min Wang; Xiaoping Liu; Peng Shi

    2011-12-01

    This paper is concerned with robust stabilization problem for a class of nonaffine pure-feedback systems with unknown time-delay functions and perturbed uncertainties. Novel continuous packaged functions are introduced in advance to remove unknown nonlinear terms deduced from perturbed uncertainties and unknown time-delay functions, which avoids the functions with control law to be approximated by radial basis function (RBF) neural networks. This technique combining implicit function and mean value theorems overcomes the difficulty in controlling the nonaffine pure-feedback systems. Dynamic surface control (DSC) is used to avoid "the explosion of complexity" in the backstepping design. Design difficulties from unknown time-delay functions are overcome using the function separation technique, the Lyapunov-Krasovskii functionals, and the desirable property of hyperbolic tangent functions. RBF neural networks are employed to approximate desired virtual controls and desired practical control. Under the proposed adaptive neural DSC, the number of adaptive parameters required is reduced significantly, and semiglobal uniform ultimate boundedness of all of the signals in the closed-loop system is guaranteed. Simulation studies are given to demonstrate the effectiveness of the proposed design scheme.

  8. High-resistance controlled yielding supporting technique in deep-well oil shale roadways

    Institute of Scientific and Technical Information of China (English)

    Yu Yang; Bai Jianbiao; Wang Xiangyu; Wang Junde; Xue Shizhi; Xu Ke

    2014-01-01

    In order to avoid the deep-well oil shale roadway being deformed, damaged, or difficult to maintain after excavating and supporting in Haishiwan coal mine, this paper has analyzed the characteristics of the deformed roadway and revealed its failure mechanism by taking comprehensively the methods of field geological investigation, displacement monitoring of surrounding rock, rock properties and hydration properties experiments and field application tests. Based on this work, the high-resistance controlled yielding supporting principle is proposed, which is:to‘resist’ by high pre-tightening force and high stiff-ness in the early stage, to‘yield’ by making use of the controlled deformation of a yielding tube in the middle stage, and to‘fix’ by applying total-section Gunite in the later stage. A high-resistance controlled yielding supporting technique of‘high pre-tightening force yielding anchor bolt+small-bore pre-tight-ening force anchor cable+rebar ladder beam+rhombic metal mesh+lagging gunite’ has been estab-lished, and industrial on site testing implemented. The practical results show that the high-resistance controlled yielding supporting technique can effectively control the large deformation and long-time rhe-ology of deep-well oil shale roadways and can provide beneficial references for the maintenance of other con-generic roadways.

  9. An electronic control for an electrohydraulic active control landing gear for the F-4 aircraft

    Science.gov (United States)

    Ross, I.

    1982-01-01

    A controller for an electrohydraulic active control landing gear was developed for the F-4 aircraft. A controller was modified for this application. Simulation results indicate that during landing and rollout over repaired bomb craters the active gear effects a force reduction, relative to the passive gear, or approximately 70%.

  10. Optimizing insulin injection technique and its effect on blood glucose control

    OpenAIRE

    Giorgio Grassi, MD; Paola Scuntero, RN; Rosalba Trepiccioni, RN; Francesca Marubbi, PhD; Kenneth Strauss, MD

    2014-01-01

    Purpose: The purpose of the study is to assess whether proper Injection Technique (IT) is associated with improved glucose control over a three month period. Methods: Patients (N = 346) with diabetes from 18 ambulatory centers throughout northern Italy who had been injecting insulin ≥ four years answered a questionnaire about their IT. The nurse then examined the patient's injection sites for the presence of lipohypertrophy (LH), followed by an individualized training session in which sub-...

  11. Advancements in non-destructive control of efficiency of electrochemical repair techniques

    OpenAIRE

    Martínez Sierra, Isabel

    2009-01-01

    [EN] The main electrochemical techniques used for reducing corrosion on reinforced structures are cathodic protection (CP), electrochemical chloride extraction (ECE) and realkalisation (ER). Traditionally, for controlling the efficiency of CP, standard methods based in the depolarisation of rebar are used, with inconvenience of requiring the interruption of the protection current even for several hours. Concerning ECE and ER, the usual methods involve extraction and chemical analysis (chlorid...

  12. Thematic Plan for Fruit Fly Control Using the Sterile Insect Technique

    International Nuclear Information System (INIS)

    This thematic plan for fruit flies is the summation of ideas and recommendations put forth by a group of experts composed of fruit fly program managers and workers, stakeholders from the affected industry, a commodity specialist from the FAO, and technical, planning and policy specialists from the IAEA and the FAO. This document provides strategic guidance and direction on how and where the Sterile Insect Technique (SIT) can most effectively be applied to control or eradicate fruit flies in the future.

  13. Oil whip instability control using μ-synthesis technique on a magnetic actuator

    Science.gov (United States)

    Riemann, Bernd; Araujo Perini, Efrain; Lucchesi Cavalca, Katia; Fiori de Castro, Helio; Rinderknecht, Stephan

    2013-02-01

    Rotating machines have a wide application range and since those machines have high trust levels, several rotor vibrations control methods are investigated in order to avoid sudden cracks, improve rotor performance or even to reach higher operation speeds by controlling some instabilities, critical speeds resonances or oil whip effect. Rotor instabilities are associated to the operation speed and can have structural or dynamic sources from the shaft, bearings and foundation or even from an actuator external force. This work focuses on a strategy that uses the μ-synthesis control technique to attenuate the oil whip instability effect of flexible hydrodynamically supported rotors and allows the rotor to operate in higher speeds. For the identified rotor model and the synthesized controller applied on a magnetic actuator, the control system stability and performance specifications are analyzed with regard to the model uncertainties and μ-synthesis controlled vibration levels are compared to PID controller in vertical and horizontal directions. The performance specifications within the μ-synthesis are optimized to suppress unbalance vibration and, in order to contribute to industrial acceptance, the controller design is presented as a strategy which focuses on a design at reduced effort.

  14. A Novel BLDC-Like DTC Control Technique for Induction Motors

    Directory of Open Access Journals (Sweden)

    Andrea Rossi

    2012-01-01

    Full Text Available DC brushless motors are widely adopted for their simplicity of control, even in sensorless configuration, and their high torque density. On the other hand, induction motors are very economical due to the absence of permanent magnets; for the same reason they can easily be driven in the flux-weakening region to attain a wide speed range. Nevertheless, high dynamic induction motors drives, based on field-oriented (FOC or predictive control, require large amounts of computing power and are rather sensitive to motor parameter variations. This paper presents a simple DTC induction motor control algorithm based on a well-known BLDC control technique, which allows to realize a high dynamic induction motor speed control with wide speed range. The firmware implementation is very compact and occupies a low amount of program memory, comparable to volt-per-Hertz- (V/f- based control algorithms. The novel control algorithm presents also good performance and low current ripple and can be implemented on a low-cost motion control DSP without resorting to high-frequency PWM.

  15. Modelling Aedes aegypti mosquito control via transgenic and sterile insect techniques: Endemics and emerging outbreaks

    KAUST Repository

    Seirin Lee, S.

    2013-08-01

    The invasion of pest insects often changes or destroys a native ecosystem, and can result in food shortages and disease endemics. Issues such as the environmental effects of chemical control methods, the economic burden of maintaining control strategies and the risk of pest resistance still remain, and mosquito-borne diseases such as malaria and dengue fever prevail in many countries, infecting over 100 million worldwide in 2010. One environmentally friendly method for mosquito control is the Sterile Insect Technique (SIT). This species-specific method of insect control relies on the mass rearing, sterilization and release of large numbers of sterile insects. An alternative transgenic method is the Release of Insects carrying a Dominant Lethal (RIDL). Our objective is to consider contrasting control strategies for two invasive scenarios via SIT and RIDL: an endemic case and an emerging outbreak. We investigate how the release rate and size of release region influence both the potential for control success and the resources needed to achieve it, under a range of conditions and control strategies, and we discuss advantageous strategies with respect to reducing the release resources and strategy costs (in terms of control mosquito numbers) required to achieve complete eradication of wild-type mosquitoes. © 2013 Elsevier Ltd.

  16. Geometric control of active collective motion

    CERN Document Server

    Theillard, Maxime; Saintillan, David

    2016-01-01

    Recent experimental studies have shown that confinement can profoundly affect self-organization in semi-dilute active suspensions, leading to striking features such as the formation of steady and spontaneous vortices in circular domains and the emergence of unidirectional pumping motions in periodic racetrack geometries. Motivated by these findings, we analyze the two-dimensional dynamics in confined suspensions of active self-propelled swimmers using a mean-field kinetic theory where conservation equations for the particle configurations are coupled to the forced Navier-Stokes equations for the self-generated fluid flow. In circular domains, a systematic exploration of the parameter space casts light on three distinct states: equilibrium with no flow, stable vortex, and chaotic motion, and the transitions between these are explained and predicted quantitatively using a linearized theory. In periodic racetracks, similar transitions from equilibrium to net pumping to traveling waves to chaos are observed in ag...

  17. Applying the sterile insect technique to the control of insect pests

    International Nuclear Information System (INIS)

    The sterile insect technique (SIT) is basically a novel twentieth century approach to insect birth control. It is species specific and exploits the mate seeking behaviour of the insect. The basic principle is simple. Insects are mass reared in 'factories' and sexually sterilized by gamma rays from a 60Co source. The sterile insects are then released in a controlled fashion into nature. Matings between the sterile insects released and native insects produced no progeny. If enough of these matings take place, reproduction of the pest population decreases. With continued release, the pest population can be controlled and in some cases eradicated. In the light of the many important applications of the SIT worldwide and the great potential that SIT concepts hold for insect and pest control in developing countries, two special benefits should be stressed. Of greatest significance is the fact that the SIT permits suppression and eradication of insect pests in an environmentally harmless manner. It combines nuclear techniques with genetic approaches and, in effect, replaces intensive use of chemicals in pest control. Although chemicals are used sparingly at the outset in some SIT programmes to reduce the size of the pest population before releases of sterilized insects are started, the total amount of chemicals used in an SIT programme is a mere fraction of what would be used without the SIT. It is also of great importance that the SIT is not designed strictly for the eradication of pest species but can readily be used in the suppression of insect populations. In fact, the SIT is ideally suited for use in conjunction with other agricultural pest control practices such as the use of parasites and predators, attractants and cultural controls (e.g. ploughing under or destruction of crop residues) in integrated pest management programmes to achieve control at the lowest possible price and with a minimum of chemical contamination of the environment

  18. Application of High Order X-LMS Filter for Active Noise Control

    OpenAIRE

    N.V.K.Mahalakshmi; Sindhu, D; B. Ranjith Kumar; N.Santhisri; G. Sowjanya Rao

    2014-01-01

    In this paper active noise is controlled by using higher order X-LMS (least mean square) filter. This technique is based on X-NLMS (normalized least mean square), also known as traditional acoustic noise cancellation (ANC) scheme. It cancels the wideband noise from the corrupted speech signal. The active noise reducing headphone is probably the most successful application of active control of sound – the technology of cancelling sound with sound i.e., by using anti-noise signal. This report p...

  19. Closed Loop Control of Active Damped Small DC-link Capacitor Based Drive

    DEFF Research Database (Denmark)

    Maheshwari, Ram Krishan; Munk-Nielsen, Stig

    2010-01-01

    A new method of active damping for small DC-link capacitor based drive system is implemented in stator flux oriented control for an induction machine. The active damping technique is based on a detailed model of the drive system which leads to a very simple implementation. The active damping can...... be achieved either by modifying the machine current reference or by modifying the machine voltage. The correlation between these two methods is shown by using simple analysis and it is verified by experimental results in a three phase induction machine drive. The effect of current control loop bandwidth...

  20. Activity meters permitting direct activity readings for food controls

    International Nuclear Information System (INIS)

    Instruments for total gamma activity measurements can only be used, if the calibration factor is known for the radionuclide mixture to be measured in each case. This is determined using spectroscopes calibrated on the basis of reference samples. Inaccuracies of measurement performed on equal volumes are caused by the fact that specific weights vary between foodstuffs and must therefore be made up for by adequate adjustments. As any radioactivity occurring naturally in the specimens cannot be distinguished from manmade radioactivity, it may be impossible to interpret results lower than some 100 Bq/kg for certain samples influenced by potassium (legume, dry milk) or uranium-radium (soil). The instruments incorporate annular receptacles for the samples and NaI(Tl) detectors for the measurement of gamma-emitting radionuclides in liquids, plant materials and foodstuffs, which have a reading for such activities in Bq/l or Bq/kg (Becquerel monitors). (orig./DG)

  1. Non-Foster Impedance Wideband Matching Technique for Electrically Small Active Antenna

    Directory of Open Access Journals (Sweden)

    Wenxing Li

    2013-01-01

    Full Text Available This paper investigates a non-Foster wideband circuit matching technique for an electrically small antenna (ESA. By introducing a negative impedance convertor into an active network, the active network can obtain an equivalent input gain at input port to improve gain, sensitivity and output ratio of signal to noise. In addition, it also increases the effective height of active antenna. The experimental results have verified the proposed method by using a 100 KHz–30 MHz wideband active receiving monopole antenna.

  2. HPLC-MS technique in radiopharmaceutical research (the quality control of 18F-2-fluorodeoxyglucose as an example)

    International Nuclear Information System (INIS)

    Application of radiopharmaceuticals puts increasing demands on their quality control, considering the short half-times, high specific activities (auto-radiolytic effects), and general quality (chemical purity, apyrogenity and sterility) of pharmacy. Mostly, the radioanalytical control consists of application of several separation and instrumental analytical techniques. In this paper, perspective of the hyphenated HPLC and MS techniques is demonstrated on the example of one of the most spread radiopharmaceutical, 2-[18F]fluoro-2-deoxy-D-glucose (further as FDG). In this work, a liquid chromatography/refractive index detector/radiometric detector/mass spectrometric detector combination (HPLC/RID/RAD/MSD) was used for development of a complex routine technique. Optimization of HPLC/MS analysis was performed investigating the electrospray ionization (ESI) analytical signal of mass spectrometer as a function of various eluent composition (see this book, p. 39). Some results, illustrating the glucose and FDG ESI-MS, and also composition of FDG after autoradiolysis, which were obtained either by a TOF Mariner (Perkin Elmer) mass-spectrometer and Agilent 1100 HPLC-MS equipment with quadrupole MS detector are discussed. They give evidence of admixtures and radiolytic formation of deoxyglucose, deoxychloroglucose, erythrose, erytritol, gluconic acid, lactose, raffinose, saccharic acid, sorbitol/[19F]FDG, xylitol, and also univalent ions of C6H10O7F.H2O and C6H12O8 compounds. The results indicate that the emerging demands on radiopharmaceuticals quality control can be fulfilled in-time only by the radio-HPLC technique developed by the help of a tandem mass-spectrometric detector. (authors)

  3. Applying the sterile insect technique to the control of insect pests

    International Nuclear Information System (INIS)

    The sterile insect technique involves the mass-rearing of insects, which are sterilized by gamma rays from a 60Co source before being released in a controlled fashion into nature. Matings between the sterile insects released and native insects produce no progeny, and so if enough of these matings occur the pest population can be controlled or even eradicated. A modification of the technique, especially suitable for the suppression of the moths and butterflies, is called the F, or inherited sterility method. In this, lower radiation doses are used such that the released males are only partially sterile (30-60%) and the females are fully sterile. When released males mate with native females some progeny are produced, but they are completely sterile. Thus, full expression of the sterility is delayed by one generation. This article describes the use of the sterile insect technique in controlling the screwworm fly, the tsetse fly, the medfly, the pink bollworm and the melon fly, and of the F1 sterility method in the eradication of local gypsy moth infestations. 18 refs, 5 figs, 1 tab

  4. Carrier-Based Common Mode Voltage Control Techniques in Three-Level Diode-Clamped Inverter

    Directory of Open Access Journals (Sweden)

    Pradyumn Chaturvedi

    2012-01-01

    Full Text Available Switching converters are used in electric drive applications to produce variable voltage, variable frequency supply which generates harmful large dv/dt and high-frequency common mode voltages (CMV. Multilevel inverters generate lower CMV as compared to conventional two-level inverters. This paper presents simple carrier-based technique to control the common mode voltages in multilevel inverters using different structures of sine-triangle comparison method such as phase disposition (PD, phase opposition disposition (POD by adding common mode voltage offset signal to actual reference voltage signal. This paper also presented the method to optimize the magnitude of this offset signal to reduce CMV and total harmonic distortion in inverter output voltage. The presented techniques give comparable performance as obtained in complex space vector-based control strategy, in terms of number of commutations, magnitude, and rate of change of CMV and harmonic profile of inverter output voltage. Simulation and experimental results presented confirm the effectiveness of the proposed techniques to control the common mode voltages.

  5. Comparison of the pain levels of computer-controlled and conventional anesthesia techniques in prosthodontic treatment

    Directory of Open Access Journals (Sweden)

    Murat Yenisey

    2009-10-01

    Full Text Available OBJECTIVE: The objective of this study was to compare the pain levels on opposite sides of the maxilla at needle insertion during delivery of local anesthetic solution and tooth preparation for both conventional and anterior middle superior alveolar (AMSA technique with the Wand computer-controlled local anesthesia application. MATERIAL AND METHODS: Pain scores of 16 patients were evaluated with a 5-point verbal rating scale (VRS and data were analyzed nonparametrically. Pain differences at needle insertion, during delivery of local anesthetic, and at tooth preparation, for conventional versus the Wand technique, were analyzed using the Mann-Whitney U test (p=0.01. RESULTS: The Wand technique had a lower pain level compared to conventional injection for needle insertion (p0.05. CONCLUSIONS: The AMSA technique using the Wand is recommended for prosthodontic treatment because it reduces pain during needle insertion and during delivery of local anaesthetic. However, these two techniques have the same pain levels for tooth preparation.

  6. Statistical learning techniques applied to epidemiology: a simulated case-control comparison study with logistic regression

    Directory of Open Access Journals (Sweden)

    Land Walker H

    2011-01-01

    Full Text Available Abstract Background When investigating covariate interactions and group associations with standard regression analyses, the relationship between the response variable and exposure may be difficult to characterize. When the relationship is nonlinear, linear modeling techniques do not capture the nonlinear information content. Statistical learning (SL techniques with kernels are capable of addressing nonlinear problems without making parametric assumptions. However, these techniques do not produce findings relevant for epidemiologic interpretations. A simulated case-control study was used to contrast the information embedding characteristics and separation boundaries produced by a specific SL technique with logistic regression (LR modeling representing a parametric approach. The SL technique was comprised of a kernel mapping in combination with a perceptron neural network. Because the LR model has an important epidemiologic interpretation, the SL method was modified to produce the analogous interpretation and generate odds ratios for comparison. Results The SL approach is capable of generating odds ratios for main effects and risk factor interactions that better capture nonlinear relationships between exposure variables and outcome in comparison with LR. Conclusions The integration of SL methods in epidemiology may improve both the understanding and interpretation of complex exposure/disease relationships.

  7. Radon Control Activities for Lung Cancer Prevention in National Comprehensive Cancer Control Program Plans, 2005–2011

    OpenAIRE

    Antonio Neri, MD, MPH; Sherri L. Stewart, PhD; William Angell, MS

    2013-01-01

    Introduction Radon is the second leading cause of lung cancer among smokers and the leading cause among nonsmokers. The US Environmental Protection Agency recommends that every home be tested for radon. Comprehensive Cancer Control (CCC) programs develop cancer coalitions that coordinate funding and resources to focus on cancer activities that are recorded in cancer plans. Radon tests, remediation, and radon mitigation techniques are relatively inexpensive, but it is unclear whether coalition...

  8. A reduced energy supply strategy in active vibration control

    International Nuclear Information System (INIS)

    In this paper, a control strategy is presented and numerically tested. This strategy aims to achieve the potential performance of fully active systems with a reduced energy supply. These energy needs are expected to be comparable to the power demands of semi-active systems, while system performance is intended to be comparable to that of a fully active configuration. The underlying strategy is called 'global semi-active control'. This control approach results from an energy investigation based on management of the optimal control process. Energy management encompasses storage and convenient restitution. The proposed strategy monitors a given active law without any external energy supply by considering purely dissipative and energy-demanding phases. Such a control law is offered here along with an analysis of its properties. A suboptimal form, well adapted for practical implementation steps, is also given. Moreover, a number of numerical experiments are proposed in order to validate test findings

  9. Linear Quadratic Integral Control for the Active Suspension of Vehicle

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The quarter model of an active suspension is established in the form of controllable autoregressive moving average (CARMA) model. An accelerometer can be mounted on the wheel hub for measuring road disturbance; this signal is used to identify the CARMA model parameters by recursive forgetting factors least square method. The linear quadratic integral (LQI) control method for the active suspension is presented. The LQI control algorithm is fit for vehicle suspension control, for the control performance index can comprise multi controlled variables. The simulation results show that the vertical acceleration and suspension travel both are decreased with the LQI control in the low frequency band, and the suspension travel is increased with the LQI control in the middle or high frequency band. The suspension travel is very small in the middle or high frequency band, the suspension bottoming stop will not happen, so the vehicle ride quality can be improved apparently by the LQI control.

  10. Active noise control and application; Active soon seigyo gijutsu to sono tekiyorei

    Energy Technology Data Exchange (ETDEWEB)

    Muto, M.; Hayashi, M.; Kawai, T.; Sato, F.; Kanbe, K. [Ishikawajima-Harima Heavy Industries Co. Ltd., Tokyo (Japan); Inoue, Y.; Takada, K.

    1995-11-01

    The recent rapid progress of electronic devices and signal processing techniques has allowed the practical application of active noise control(ANC) for reduction of noise. The principle of ANC is to cancel a noise by an anti-noise which has the same amplitude of the noise but the inverse phase. For noise reduction in gas ducts, the one dimensional ANC theory can be applied. However, there are still several technical issues particulars to individual plants to be studied and solved. This paper describes the ANC system using the hydraulically actuated speaker which has been developed at IHI, and applications to reduction of low frequency sound emitted at the exit of a stack from a large induction fan. Another application for tractor cabin is also described, indicating successful noise reduction. 6 refs., 12 figs.

  11. Active Vibration Control of Satellite Flexible Structures during Attitude Maneuvers

    OpenAIRE

    Saeed Hemmati; Morteza Shahravi; Keramat Malekzadeh

    2013-01-01

    The purpose of this study is controlling active vibration of satellite flexible structures during attitude maneuvers. A smart structure is a structure which is able to sense and control active reaction to any external factors and stimulation. As it comes from the definition of smart structures, development of this knowledge depends on the materials science development, theories and strategies for control. In materials science, smart materials are developed in such a way that they are able to ...

  12. Active control of noise radiation from vibrating structures

    DEFF Research Database (Denmark)

    Mørkholt, Jakob

    The thesis is concerned with the active control of randomly vibrating structures by means of feedback control, with particular emphasis on reducing the sound radiation from such structures. A time domain model of the structural and radiation dynamics of an actively controlled plate has been...... developed, based on the theory of radiation filters for estimating the sound radiation from multimodal vibrations. This model has then been used in simulations of optimal feedback control, with special emphasis of the stability margins of the optimal control scheme. Two different methods of designing...

  13. STATISTIC LINEARIZATION CONTROL FOR HYDRAULIC ACTIVE DAMPING SUSPENSION

    Institute of Scientific and Technical Information of China (English)

    Wang Qingfeng; Zhao Ju; Yang Botao

    2000-01-01

    A statistic linearization analysis method of bad nolinear hydraulic active damping suspensiop is provided.Also the optimum control strategy of semi-active suspension and graded control strategy based on it are puted forward.Experimental researches are carried out on a 2 DOF (degree of freedom ) hydraulic active damping suspension test system.The results showed that an excellent control effectiveness could be obtained by using statistic linearization optimum control which unfortunely requests continuously regulationg the damp in an accurate way and costs much in engeering application.On the contrary,the results also showed that graded control is more practicable which has a control effectiveness close to the optimum control and costs less.

  14. Control strategies for active lower extremity prosthetics and orthotics: a review

    OpenAIRE

    Tucker, M R; Olivier, J; Pagel, A; Bleuler, H.; Bouri, M.; Lambercy, O.; del R. Millan, J.; Riener, R.; Vallery, H; Gassert, R.

    2015-01-01

    Technological advancements have led to the development of numerous wearable robotic devices for the physical assistance and restoration of human locomotion. While many challenges remain with respect to the mechanical design of such devices, it is at least equally challenging and important to develop strategies to control them in concert with the intentions of the user. This work reviews the state-of-the-art techniques for controlling portable active lower limb prosthetic and orthotic (P/O) de...

  15. Controlling the enzymatic activity of a restriction enzyme by light

    OpenAIRE

    Schierling, Benno; Noël, Ann-Josée; Wende, Wolfgang; Hien, Le Thi; Volkov, Eugeny; Kubareva, Elena; Oretskaya, Tatiana; Kokkinidis, Michael; Römpp, Andreas; Spengler, Bernhard; Pingoud, Alfred

    2009-01-01

    For many applications it would be desirable to be able to control the activity of proteins by using an external signal. In the present study, we have explored the possibility of modulating the activity of a restriction enzyme with light. By cross-linking two suitably located cysteine residues with a bifunctional azobenzene derivative, which can adopt a cis- or trans-configuration when illuminated by UV or blue light, respectively, enzymatic activity can be controlled in a reversible manner. T...

  16. An Overview of Active Structural Control under Seismic Loads

    OpenAIRE

    Soong, T.T.; Masri, S. F.; Housner, G. W.

    1991-01-01

    The concept of active structural control as a means of structural protection against seismic loads, developed over the last 20 years, has received considerable attention in recent years. It has now reached the stage where active systems have been installed in full-scale structures. It is the purpose of this paper to provide an overview of this development with special emphasis placed on laboratory experiments using model structures and on full-scale implementation of some active control syste...

  17. JAEA − JRC collaboration on the development of active neutron NDA techniques

    OpenAIRE

    KURETA M.; Koizumi, M.; OHZU A.; Furutaka, K.; Tsuchiya, H.; SEYA M.; Harada, H.; ABOUSAHL Said; HEYSE JAN; Kopecky, Stefan; MONDELAERS Willy; PEDERSEN Bent; SCHILLEBEECKX Peter

    2015-01-01

    The Japan Atomic Energy Agency in collaboration with the Joint Research Centre of the European Commission started a program titled “Development of active neutron NDA techniques”. The program aims at developing an innovative non-destructive analysis (NDA) system for various applications in the field of nuclear safety, security and safeguards. A Non Destructive Analysis (NDA) system is proposed that is based on a combination of different active neutron interrogation techniques, i.e. DDA (Di...

  18. Brief Group Intervention Using Emotional Freedom Techniques for Depression in College Students: A Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Dawson Church

    2012-01-01

    Full Text Available Two hundred thirty-eight first-year college students were assessed using the Beck Depression Inventory (BDI. Thirty students meeting the BDI criteria for moderate to severe depression were randomly assigned to either a treatment or control group. The treatment group received four 90-minute group sessions of EFT (Emotional Freedom Techniques, a novel treatment that combines exposure, cognitive reprocessing, and somatic stimulation. The control group received no treatment. Posttests were conducted 3 weeks later on those that completed all requirements (N=18. The EFT group (n=9 had significantly more depression at baseline than the control group (n=9 (EFT BDI mean=23.44, SD=2.1 versus control BDI mean=20.33, SD=2.1. After controlling for baseline BDI score, the EFT group had significantly less depression than the control group at posttest, with a mean score in the “nondepressed” range (P=.001; EFT BDI mean=6.08, SE=1.8 versus control BDI mean=18.04, SE=1.8. Cohen's d was 2.28, indicating a very strong effect size. These results are consistent with those noted in other studies of EFT that included an assessment for depression and indicate the clinical usefulness of EFT as a brief, cost-effective, and efficacious treatment.

  19. Generalized Internal Model Robust Control for Active Front Steering Intervention

    Institute of Scientific and Technical Information of China (English)

    WU Jian; ZHAO Youqun; JI Xuewu; LIU Yahui; ZHANG Lipeng

    2015-01-01

    Because of the tire nonlinearity and vehicle’s parameters’ uncertainties, robust control methods based on the worst cases, such as H∞, μsynthesis, have been widely used in active front steering control, however, in order to guarantee the stability of active front steering system (AFS) controller, the robust control is at the cost of performance so that the robust controller is a little conservative and has low performance for AFS control. In this paper, a generalized internal model robust control (GIMC) that can overcome the contradiction between performance and stability is used in the AFS control. In GIMC, the Youla parameterization is used in an improved way. And GIMC controller includes two sections:a high performance controller designed for the nominal vehicle model and a robust controller compensating the vehicle parameters’ uncertainties and some external disturbances. Simulations of double lane change (DLC) maneuver and that of braking on split-μroad are conducted to compare the performance and stability of the GIMC control, the nominal performance PID controller and the H∞ controller. Simulation results show that the high nominal performance PID controller will be unstable under some extreme situations because of large vehicle’s parameters variations, H∞ controller is conservative so that the performance is a little low, and only the GIMC controller overcomes the contradiction between performance and robustness, which can both ensure the stability of the AFS controller and guarantee the high performance of the AFS controller. Therefore, the GIMC method proposed for AFS can overcome some disadvantages of control methods used by current AFS system, that is, can solve the instability of PID or LQP control methods and the low performance of the standard H∞controller.

  20. Study of tethered satellite active attitude control

    Science.gov (United States)

    Colombo, G.

    1982-01-01

    Existing software was adapted for the study of tethered subsatellite rotational dynamics, an analytic solution for a stable configuration of a tethered subsatellite was developed, the analytic and numerical integrator (computer) solutions for this "test case' was compared in a two mass tether model program (DUMBEL), the existing multiple mass tether model (SKYHOOK) was modified to include subsatellite rotational dynamics, the analytic "test case,' was verified, and the use of the SKYHOOK rotational dynamics capability with a computer run showing the effect of a single off axis thruster on the behavior of the subsatellite was demonstrated. Subroutines for specific attitude control systems are developed and applied to the study of the behavior of the tethered subsatellite under realistic on orbit conditions. The effect of all tether "inputs,' including pendular oscillations, air drag, and electrodynamic interactions, on the dynamic behavior of the tether are included.

  1. Determination of trace impurities of chlorine in zirconium-alloy matrices using neutron activation technique

    Energy Technology Data Exchange (ETDEWEB)

    Naik, H.; Nathaniel, T. Newton [Bhabha Atomic Research Centre, Trombay, Mumbai (India). Radiochemistry Div.; Sant, V.L. [Bhabha Atomic Research Centre, Trombay, Mumbai (India). Fuel Chemistry Div.; Suryanarayana, S.V. [Bhabha Atomic Research Centre, Trombay, Mumbai (India). Nuclear Physics Div.; Prajapati, P.M. [Bhabha Atomic Research Centre, Trombay, Mumbai (India). Reactor Physics Design Div.

    2011-07-01

    Trace impurities of chlorine in the zircaloy-2 and Zr-2.5% Nb alloy matrix have been determined using neutron activation analysis (NAA) and off-line {gamma}-ray spectrometric technique. The results have been compared with the values obtained from pyrohydrolysis-IC and spark source mass spectrometric method. The limit of internal precision error from the neutron activation technique is 6.7% for zircaloy-2 and 9% for Zr-2.5% Nb alloy, which are lower than that of pyrohydrolysis-IC and spark source mass spectrometric measurements respectively. For both alloys the results from present work based on NAA technique are slightly higher than the results based on the other two methods but are comparable within the uncertainty. Read More: http://www.oldenbourg-link.com/doi/abs/10.1524/ract.2011.1863 (orig.)

  2. Application of Time Scale to Parameters Tuning of Active Disturbance Rejection Controller for Induction Motor

    Institute of Scientific and Technical Information of China (English)

    SHAO Li-wei; LIAO Xiao-zhong; ZHANG Yu-he

    2007-01-01

    Active disturbance rejection controller (ADRC) has good performance in induction motor (IM) control system, but controller parameter is difficult to tune. A method of tuning ADRC parameter by time scale is analyzed. The IM time scale is obtained by theoretical analysis. Combining the relations between scale time and ADRC parameters, ADRC parameter tuning in IM vector control based stator flux oriented is obtained. This parameter tuning method is validated by simulations and it provides a new technique for tuning of ADRC parameters of IM.

  3. Study on the measurement technique of Fe foil's activated γ spectrum

    International Nuclear Information System (INIS)

    In this article it is comparatively systematically studied on the related measurement technique of Fe foil's activated γ spectrum and resolving-spectrum under specifical conditions, including high-threshold-energy detectors, self-absorption, self-shielding and perturbation and so on. The experimental results and the calculated results with MCNP code are analyzed and also discussed. (authors)

  4. Status of the Usage of Active Learning and Teaching Method and Techniques by Social Studies Teachers

    Science.gov (United States)

    Akman, Özkan

    2016-01-01

    The purpose of this study was to determine the active learning and teaching methods and techniques which are employed by the social studies teachers working in state schools of Turkey. This usage status was assessed using different variables. This was a case study, wherein the research was limited to 241 social studies teachers. These teachers…

  5. Regulation on the Appraisal Activities of The Products,Techniques and Applications Projects of BIRTV

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    I General Provisions 1.The Appraisal Activities of the Products,Techniques andApplications Projects of BIRTV is held for the purpose of strengthen-ing the technical advisory work and pilot role,and providing positiveguidance and effective assistance in the field of new technology

  6. Streamlined design and self reliant hardware for active control of precision space structures

    Science.gov (United States)

    Hyland, David C.; King, James A.; Phillips, Douglas J.

    1994-01-01

    Precision space structures may require active vibration control to satisfy critical performance requirements relating to line-of-sight pointing accuracy and the maintenance of precise, internal alignments. In order for vibration control concepts to become operational, it is necessary that their benefits be practically demonstrated in large scale ground-based experiments. A unique opportunity to carry out such demonstrations on a wide variety of experimental testbeds was provided by the NASA Control-Structure Integration (CSI) Guest Investigator (GI) Program. This report surveys the experimental results achieved by the Harris Corporation GI team on both Phases 1 and 2 of the program and provides a detailed description of Phase 2 activities. The Phase 1 results illustrated the effectiveness of active vibration control for space structures and demonstrated a systematic methodology for control design, implementation test. In Phase 2, this methodology was significantly streamlined to yield an on-site, single session design/test capability. Moreover, the Phase 2 research on adaptive neural control techniques made significant progress toward fully automated, self-reliant space structure control systems. As a further thrust toward productized, self-contained vibration control systems, the Harris Phase II activity concluded with experimental demonstration of new vibration isolation hardware suitable for a wide range of space-flight and ground-based commercial applications.The CSI GI Program Phase 1 activity was conducted under contract NASA1-18872, and the Phase 2 activity was conducted under NASA1-19372.

  7. HYBRID FUZZY CONTROL FOR ELECTRO-HYDRAULIC ACTIVE DAMPING SUSPENSION

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new control scheme, the hybrid fuzzy control method, for active damping suspension system is presented. The scheme is the result of effective combination of the statistical optimal control method based on the statistical property of suspension system, with the bang-bang control method based on the real-time characteristics of suspension system. Computer simulations are performed to compare the effectiveness of hybrid fuzzy control scheme with that of optimal damping control, bang-bang control, and passive suspension. It takes the effects of time-variant factors into full account. The superiority of the proposed hybrid fuzzy control scheme for active damping suspension to the passive suspension is verified in the experiment study.

  8. Adaptive Current Control with PI-Fuzzy Compound Controller for Shunt Active Power Filter

    Directory of Open Access Journals (Sweden)

    Juntao Fei

    2013-01-01

    Full Text Available An adaptive control technology and PI-fuzzy compound control technology are proposed to control an active power filter (APF. AC side current compensation and DC capacitor voltage tracking control strategy are discussed and analyzed. Model reference adaptive controller for the AC side current compensation is derived and established based on Lyapunov stability theory; proportional and integral (PI fuzzy compound controller is designed for the DC side capacitor voltage control. The adaptive current controller based on PI-fuzzy compound system is compared with the conventional PI controller for active power filter. Simulation results demonstrate the feasibility and satisfactory performance of the proposed control strategies. It is shown that the proposed control method has an excellent dynamic performance such as small current tracking error, reduced total harmonic distortion (THD, and strong robustness in the presence of parameters variation and nonlinear load.

  9. Functional Based Adaptive and Fuzzy Sliding Controller for Non-Autonomous Active Suspension System

    Science.gov (United States)

    Huang, Shiuh-Jer; Chen, Hung-Yi

    In this paper, an adaptive sliding controller is developed for controlling a vehicle active suspension system. The functional approximation technique is employed to substitute the unknown non-autonomous functions of the suspension system and release the model-based requirement of sliding mode control algorithm. In order to improve the control performance and reduce the implementation problem, a fuzzy strategy with online learning ability is added to compensate the functional approximation error. The update laws of the functional approximation coefficients and the fuzzy tuning parameters are derived from the Lyapunov theorem to guarantee the system stability. The proposed controller is implemented on a quarter-car hydraulic actuating active suspension system test-rig. The experimental results show that the proposed controller suppresses the oscillation amplitude of the suspension system effectively.

  10. A spectral identification technique for adaptive attitude control and pointing of the Space Telescope

    Science.gov (United States)

    Teuber, D. L.

    1976-01-01

    The Space Telescope is a 2.4 m class aperture optical telescope having near-diffraction-limited performance. It will be placed into earth orbit by 1980 via the Space Shuttle. The problem considered is how to achieve negligible degradation of the astronomy imaging capability (to 0.005 arc second) due to smearing by pointing motions during observations. Initially, pointing instability sources were identified and a linear stability was used to assess the magnitude of elastic body modes and to design control system compensation regions necessary for subsequent adaptive control. A spectral identification technique for this adaptive attitude control and pointing has been investigated that will alleviate requirements for comprehensive dynamic ground testing. Typical all-digital simulation results describing motions of the telescope line of sight are presented.

  11. New Diagnostic, Launch and Model Control Techniques in the NASA Ames HFFAF Ballistic Range

    Science.gov (United States)

    Bogdanoff, David W.

    2012-01-01

    This report presents new diagnostic, launch and model control techniques used in the NASA Ames HFFAF ballistic range. High speed movies were used to view the sabot separation process and the passage of the model through the model splap paper. Cavities in the rear of the sabot, to catch the muzzle blast of the gun, were used to control sabot finger separation angles and distances. Inserts were installed in the powder chamber to greatly reduce the ullage volume (empty space) in the chamber. This resulted in much more complete and repeatable combustion of the powder and hence, in much more repeatable muzzle velocities. Sheets of paper or cardstock, impacting one half of the model, were used to control the amplitudes of the model pitch oscillations.

  12. Various applications of Active Field Control (AFC)

    Science.gov (United States)

    Watanabe, Takayuki; Miyazaki, Hideo; Kishinaga, Shinji; Kawakami, Fukushi

    2003-10-01

    AFC is an electro-acoustic enhancement system, which has been under development at Yamaha Corporation. In this paper, several types of various AFC applications are discussed, while referring to representative projects for each application in Japan. (1) Realization of acoustics in a huge hall to classical music program, e.g., Tokyo International Forum. This venue is a multipurpose hall with approximately 5000 seats. AFC achieves loudness and reverberance equivalent to those of a hall with 2500 seats or fewer. (2) Optimization of acoustics for a variety of programs, e.g., Arkas Sasebo. AFC is used to create the optimum acoustics for each program, such as reverberance for classical concerts, acoustical support for opera singers, uniformity throughout the hall from the stage to under-balcony area, etc. (3) Control of room shape acoustical effect, e.g., Osaka Central Public Hall: In this renovation project, preservation of historically important architecture in the original form is required. AFC is installed to vary only the acoustical environment without architectural changes. (4) Assistance with crowd enthusiasm for sports entertainment, e.g., Tokyo Metropolitan Gymnasium. In this venue, which is designed as a very absorptive space for speech intelligibility, AFC is installed to enhance the atmosphere of live sports entertainment.

  13. CLP activities and control in Ireland

    Directory of Open Access Journals (Sweden)

    Caroline Walsh

    2011-01-01

    Full Text Available The 10th December 2010 marked a new beginning for Regulation (EC no. 1272/2008 on the classification, labelling and packaging of substances and mixtures (CLP in Ireland with the start of its operational phase. It was on this date that the administrative and enforcement provisions for CLP were encompassed in the new Chemicals Amendment Act, 2010. In this Act, the Health and Safety Authority, known as the "the Authority" is named as Competent Authority (CA for CLP, along with the Minister for Agriculture, Fisheries and Food, in respect of pesticides and plant protection products and the Beaumont Hospital Board with responsibility for receiving information relating to emergency health response. In practice, the Authority has been de facto CA for CLP since its publication on the 31st December 2008, given its role in existing classification and labelling regimes. This article focuses on the work undertaken by the Authority on CLP at a National, European and International level including its implementation, training, helpdesk, guidance, enforcement and awareness raising activities.

  14. CLP activities and control in Ireland.

    Science.gov (United States)

    Walsh, Caroline

    2011-01-01

    The 10(th) December 2010 marked a new beginning for Regulation (EC) no. 1272/2008 on the classification, labelling and packaging of substances and mixtures (CLP) in Ireland with the start of its operational phase. It was on this date that the administrative and enforcement provisions for CLP were encompassed in the new Chemicals Amendment Act, 2010. In this Act, the Health and Safety Authority, known as the "the Authority" is named as Competent Authority (CA) for CLP, along with the Minister for Agriculture, Fisheries and Food, in respect of pesticides and plant protection products and the Beaumont Hospital Board with responsibility for receiving information relating to emergency health response. In practice, the Authority has been de facto CA for CLP since its publication on the 31(st) December 2008, given its role in existing classification and labelling regimes. This article focuses on the work undertaken by the Authority on CLP at a National, European and International level including its implementation, training, helpdesk, guidance, enforcement and awareness raising activities.

  15. Wireless sensor networks for active vibration control in automobile structures

    Science.gov (United States)

    Mieyeville, Fabien; Ichchou, Mohamed; Scorletti, Gérard; Navarro, David; Du, Wan

    2012-07-01

    Wireless sensor networks (WSNs) are nowadays widely used in monitoring and tracking applications. This paper presents the feasibility of using WSNs in active vibration control strategies. The method employed here involves active-structural acoustic control using piezoelectric sensors distributed on a car structure. This system aims at being merged with a WSN whose head node collects data and processes control laws so as to command piezoelectric actuators wisely placed on the structure. We will study the feasibility of implementing WSNs in active vibration control and introduce a complete design methodology to optimize hardware/software and control law synergy in mechatronic systems. A design space exploration will be conducted so as to identify the best WSN platform and the resulting impact on control.

  16. Wireless sensor networks for active vibration control in automobile structures

    International Nuclear Information System (INIS)

    Wireless sensor networks (WSNs) are nowadays widely used in monitoring and tracking applications. This paper presents the feasibility of using WSNs in active vibration control strategies. The method employed here involves active-structural acoustic control using piezoelectric sensors distributed on a car structure. This system aims at being merged with a WSN whose head node collects data and processes control laws so as to command piezoelectric actuators wisely placed on the structure. We will study the feasibility of implementing WSNs in active vibration control and introduce a complete design methodology to optimize hardware/software and control law synergy in mechatronic systems. A design space exploration will be conducted so as to identify the best WSN platform and the resulting impact on control. (paper)

  17. Semi-active H∞ control of high-speed railway vehicle suspension with magnetorheological dampers

    Science.gov (United States)

    Zong, Lu-Hang; Gong, Xing-Long; Xuan, Shou-Hu; Guo, Chao-Yang

    2013-05-01

    In this paper, semi-active H∞ control with magnetorheological (MR) dampers for railway vehicle suspension systems to improve the lateral ride quality is investigated. The proposed semi-active controller is composed of a H∞ controller as the system controller and an adaptive neuro-fuzzy inference system (ANFIS) inverse MR damper model as the damper controller. First, a 17-degree-of-freedom model for a full-scale railway vehicle is developed and the random track irregularities are modelled. Then a modified Bouc-Wen model is built to characterise the forward dynamic characteristics of the MR damper and an inverse MR damper model is built with the ANFIS technique. Furthermore, a H∞ controller composed of a yaw motion controller and a rolling pendulum motion (lateral motion+roll motion) controller is established. By integrating the H∞ controller with the ANFIS inverse model, a semi-active H∞ controller for the railway vehicle is finally proposed. Simulation results indicate that the proposed semi-active suspension system possesses better attenuation ability for the vibrations of the car body than the passive suspension system.

  18. Optical tools and techniques for aligning solar payloads with the SPARCS control system. [Solar Pointing Aerobee Rocket Control System

    Science.gov (United States)

    Thomas, N. L.; Chisel, D. M.

    1976-01-01

    The success of a rocket-borne experiment depends not only on the pointing of the attitude control system, but on the alignment of the attitude control system to the payload. To ensure proper alignment, special optical tools and alignment techniques are required. Those that were used in the SPARCS program are described and discussed herein. These tools include theodolites, autocollimators, a 38-cm diameter solar simulator, a high-performance 1-m heliostat to provide a stable solar source during the integration of the rocket payload, a portable 75-cm sun tracker for use at the launch site, and an innovation called the Solar Alignment Prism. Using the real sun as the primary reference under field conditions, the Solar Alignment Prism facilitates the coalignment of the attitude sun sensor with the payload. The alignment techniques were developed to ensure the precise alignment of the solar payloads to the SPARCS attitude sensors during payload integration and to verify the required alignment under field conditions just prior to launch.

  19. The utilization of six sigma and statistical process control techniques in surgical quality improvement.

    Science.gov (United States)

    Sedlack, Jeffrey D

    2010-01-01

    Surgeons have been slow to incorporate industrial reliability techniques. Process control methods were applied to surgeon waiting time between cases, and to length of stay (LOS) after colon surgery. Waiting times between surgeries were evaluated by auditing the operating room records of a single hospital over a 1-month period. The medical records of 628 patients undergoing colon surgery over a 5-year period were reviewed. The average surgeon wait time between cases was 53 min, and the busiest surgeon spent 291/2 hr in 1 month waiting between surgeries. Process control charting demonstrated poor overall control of the room turnover process. Average LOS after colon resection also demonstrated very poor control. Mean LOS was 10 days. Weibull's conditional analysis revealed a conditional LOS of 9.83 days. Serious process management problems were identified in both analyses. These process issues are both expensive and adversely affect the quality of service offered by the institution. Process control mechanisms were suggested or implemented to improve these surgical processes. Industrial reliability and quality management tools can easily and effectively identify process control problems that occur on surgical services. PMID:20946422

  20. Controlled physical activity for functional operability determination

    Directory of Open Access Journals (Sweden)

    Luchenkov А.А.

    2014-06-01

    Full Text Available The aim: to use veloergometry test at patients of high anaeshtesiology-operative risk before traumatic operations for functional operability determination. Material and methods: Randomized prospective research with the double "blind" control has been performed at 95 patients of high risk (ASA>III, undergoing long and traumatic operations on thoracic and abdominal organs. Patients have divided into groups without complications and with complications (51 and 44 patients which one day prior to operation have spent veloergometry test (VEMT. Average dynamic pressure (ADP, the general peripheral resistance of vessels (GPRV, a core index (Cl; arterio-venous (a-v difference on oxygen, oxygen delivery to tissues, consumption of oxygen and coefficients extraction oxygen in tissues; energy consumption have been investigated. Statistics has been done by nonparametric methods. Results. In response to veloergometry test in both groups growth of Cl at the expense of a tachycardia and GPRV fall which in complication group remains above norm is noted. In group without complications coefficients extraction oxygen in tissues were normalised, a-v difference on 02 became above norm, in other group — coefficients extraction oxygen in tissues and a-v difference on 02 began to exceed norm, and oxygen consumption has grown almost in 2 times. After VEMT a-v a difference on О and oxygen consumption were essentially above in group with complications. Under the influence of VEMT markecT stabilization of function of vegetative nervous systems (VNS. The number of complications made 39: intraoperation cardiovascular — 23, postoperative respiratory — 16. Clinically important connection (p=0,069 of perioperative complications with growth a-v differences on oxygen and a power interchanging have been received. Conclusion. Thus, the oxygen-energy exchange and the vegetative status can be referred to clinical functional operability determination.