WorldWideScience

Sample records for activity control technique

  1. Active vibration control by robust control techniques

    International Nuclear Information System (INIS)

    Lohar, F.A.

    2001-01-01

    This paper studies active vibration control of multi-degree-of-freedom system. The control techniques considered are LTR, H/sup 2/ and H/sup infinite/. The results show that LTR controls the vibration but its respective settling time is higher than that of the other techniques. The control performance of H/sup infinite/ control is similar to that of H/sup 2/ control in the case of it weighting functions. However, H/sup infinite/ control is superior to H/sup 2/ control with respect to robustness, steady state error and settling time. (author)

  2. 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.

  3. A novel technique for active vibration control, based on optimal

    Indian Academy of Sciences (India)

    In the last few decades, researchers have proposed many control techniques to suppress unwanted vibrations in a structure. In this work, a novel and simple technique is proposed for the active vibration control. In this technique, an optimal tracking control is employed to suppress vibrations in a structure by simultaneously ...

  4. 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...

  5. Active noise control technique and its application on ships

    Directory of Open Access Journals (Sweden)

    CHEN Kean

    2017-08-01

    Full Text Available Due to the rapid development during past three decades, Active Noise Control(ANC has become a highly complementary noise control approach in comparison with traditional approaches, and has formed a complete system including basic theory, investigation approach, key techniques and system implementation. Meanwhile, substantial progress has been achieved in such fields as the practical application, industrialization development and commercial popularization of ANC, and this developed technique provides a practical and feasible choice for the active control of ship noise. In this review paper, its sound field analysis, system setup and key techniques are summarized, typical examples of ANC-based engineering applications including control of cabin noise and duct noise are briefly described, and a variety of forefronts and problems associated with the applications of ANC in ship noise control, such as active sound absorption, active sound insulation and smart acoustic structure, are subsequently discussed.

  6. A Novel Sliding Mode Control Technique for Indirect Current Controlled Active Power Filter

    Directory of Open Access Journals (Sweden)

    Juntao Fei

    2012-01-01

    Full Text Available A novel sliding mode control (SMC method for indirect current controlled three-phase parallel active power filter is presented in this paper. There are two designed closed loops in the system: one is the DC voltage controlling loop and the other is the reference current tracking loop. The first loop with a PI regulator is used to control the DC voltage approximating to the given voltage of capacitor, and the output of PI regulator through a low-pass filter is applied as the input of the power supply reference currents. The second loop implements the tracking of the reference currents using integral sliding mode controller, which can improve the harmonic treating performance. Compared with the direct current control technique, it is convenient to be implemented with digital signal processing system because of simpler system structure and better harmonic treating property. Simulation results verify that the generated reference currents have the same amplitude with the load currents, demonstrating the superior harmonic compensating effects with the proposed shunt active power filter compared with the hysteresis method.

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

    KAUST Repository

    Radwan, A.G.; Moaddy, K.; Salama, Khaled N.; Momani, S.; Hashim, I.

    2013-01-01

    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.

  8. 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.

  9. Analysis technique for controlling system wavefront error with active/adaptive optics

    Science.gov (United States)

    Genberg, Victor L.; Michels, Gregory J.

    2017-08-01

    The ultimate goal of an active mirror system is to control system level wavefront error (WFE). In the past, the use of this technique was limited by the difficulty of obtaining a linear optics model. In this paper, an automated method for controlling system level WFE using a linear optics model is presented. An error estimate is included in the analysis output for both surface error disturbance fitting and actuator influence function fitting. To control adaptive optics, the technique has been extended to write system WFE in state space matrix form. The technique is demonstrated by example with SigFit, a commercially available tool integrating mechanical analysis with optical analysis.

  10. Effects of Active and Passive Control Techniques on Mach 1.5 Cavity Flow Dynamics

    Directory of Open Access Journals (Sweden)

    Selin Aradag

    2017-01-01

    Full Text Available Supersonic flow over cavities has been of interest since 1960s because cavities represent the bomb bays of aircraft. The flow is transient, turbulent, and complicated. Pressure fluctuations inside the cavity can impede successful weapon release. The objective of this study is to use active and passive control methods on supersonic cavity flow numerically to decrease or eliminate pressure oscillations. Jet blowing at several locations on the front and aft walls of the cavity configuration is used as an active control method. Several techniques are used for passive control including using a cover plate to separate the flow dynamics inside and outside of the cavity, trailing edge wall modifications, such as inclination of the trailing edge, and providing curvature to the trailing edge wall. The results of active and passive control techniques are compared with the baseline case in terms of pressure fluctuations, sound pressure levels at the leading edge, trailing edge walls, and cavity floor and in terms of formation of the flow structures and the results are presented. It is observed from the results that modification of the trailing edge wall is the most effective of the control methods tested leading to up to 40 dB reductions in cavity tones.

  11. On the Active and Passive Flow Separation Control Techniques over Airfoils

    Science.gov (United States)

    Moghaddam, Tohid; Banazadeh Neishabouri, Nafiseh

    2017-10-01

    In the present work, recent advances in the field of the active and passive flow separation control, particularly blowing and suction flow control techniques, applied on the common airfoils are briefly reviewed. This broad research area has remained the point of interest for many years as it is applicable to various applications. The suction and blowing flow control methods, among other methods, are more technically feasible and market ready techniques. It is well established that the uniform and/or oscillatory blowing and suction flow control mechanisms significantly improve the lift-to-drag ratio, and further, postpone the boundary layer separation as well as the stall. The oscillatory blowing and suction flow control, however, is more efficient compared to the uniform one. A wide range of parameters is involved in controlling the behavior of a blowing and/or suction flow control, including the location, length, and angle of the jet slots. The oscillation range of the jet slot is another substantial parameter.

  12. 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.

  13. Development of an Active Flow Control Technique for an Airplane High-Lift Configuration

    Science.gov (United States)

    Shmilovich, Arvin; Yadlin, Yoram; Dickey, Eric D.; Hartwich, Peter M.; Khodadoust, Abdi

    2017-01-01

    This study focuses on Active Flow Control methods used in conjunction with airplane high-lift systems. The project is motivated by the simplified high-lift system, which offers enhanced airplane performance compared to conventional high-lift systems. Computational simulations are used to guide the implementation of preferred flow control methods, which require a fluidic supply. It is first demonstrated that flow control applied to a high-lift configuration that consists of simple hinge flaps is capable of attaining the performance of the conventional high-lift counterpart. A set of flow control techniques has been subsequently considered to identify promising candidates, where the central requirement is that the mass flow for actuation has to be within available resources onboard. The flow control methods are based on constant blowing, fluidic oscillators, and traverse actuation. The simulations indicate that the traverse actuation offers a substantial reduction in required mass flow, and it is especially effective when the frequency of actuation is consistent with the characteristic time scale of the flow.

  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)

    EBY, J.L.

    2000-01-01

    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. Stochastic Feedforward Control Technique

    Science.gov (United States)

    Halyo, Nesim

    1990-01-01

    Class of commanded trajectories modeled as stochastic process. Advanced Transport Operating Systems (ATOPS) research and development program conducted by NASA Langley Research Center aimed at developing capabilities for increases in capacities of airports, safe and accurate flight in adverse weather conditions including shear, winds, avoidance of wake vortexes, and reduced consumption of fuel. Advances in techniques for design of modern controls and increased capabilities of digital flight computers coupled with accurate guidance information from Microwave Landing System (MLS). Stochastic feedforward control technique developed within context of ATOPS program.

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

    DEFF Research Database (Denmark)

    Nicoletti, Rodrigo; Santos, Ilmar

    2003-01-01

    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 count with the conventional hydrodynamic lubrication. For furt......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...... 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 to 80 Hz). The feasibility of eliminating rotor-bearing instabilities (phenomena of whirl) by using active lubrication is also investigated...

  18. Guidance, Navigation, and Control Techniques and Technologies for Active Satellite Removal

    Science.gov (United States)

    Ortega Hernando, Guillermo; Erb, Sven; Cropp, Alexander; Voirin, Thomas; Dubois-Matra, Olivier; Rinalducci, Antonio; Visentin, Gianfranco; Innocenti, Luisa; Raposo, Ana

    2013-09-01

    This paper shows an internal feasibility analysis to de- orbit a non-functional satellite of big dimensions by the Technical Directorate of the European Space Agency ESA. The paper focuses specifically on the design of the techniques and technologies for the Guidance, Navigation, and Control (GNC) system of the spacecraft mission that will capture the satellite and ultimately will de-orbit it on a controlled re-entry.The paper explains the guidance strategies to launch, rendezvous, close-approach, and capture the target satellite. The guidance strategy uses chaser manoeuvres, hold points, and collision avoidance trajectories to ensure a safe capture. It also details the guidance profile to de-orbit it in a controlled re-entry.The paper continues with an analysis of the required sensing suite and the navigation algorithms to allow the homing, fly-around, and capture of the target satellite. The emphasis is placed around the design of a system to allow the rendezvous with an un-cooperative target, including the autonomous acquisition of both the orbital elements and the attitude of the target satellite.Analysing the capture phase, the paper provides a trade- off between two selected capture systems: the net and the tentacles. Both are studied from the point of view of the GNC system.The paper analyses as well the advanced algorithms proposed to control the final compound after the capture that will allow the controlled de-orbiting of the assembly in a safe place in the Earth.The paper ends proposing the continuation of this work with the extension to the analysis of the destruction process of the compound in consecutive segments starting from the entry gate to the rupture and break up.

  19. Use of the Generating Options for Active Risk Control (GO-ARC) Technique can lead to more robust risk control options.

    Science.gov (United States)

    Card, Alan J; Simsekler, Mecit Can Emre; Clark, Michael; Ward, James R; Clarkson, P John

    2014-01-01

    Risk assessment is widely used to improve patient safety, but healthcare workers are not trained to design robust solutions to the risks they uncover. This leads to an overreliance on the weakest category of risk control recommendations: administrative controls. Increasing the proportion of non-administrative risk control options (NARCOs) generated would enable (though not ensure) the adoption of more robust solutions. Experimentally assess a method for generating stronger risk controls: The Generating Options for Active Risk Control (GO-ARC) Technique. Participants generated risk control options in response to two patient safety scenarios. Scenario 1 (baseline): All participants used current practice (unstructured brainstorming). Scenario 2: Control group used current practice; intervention group used the GO-ARC Technique. To control for individual differences between participants, analysis focused on the change in the proportion of NARCOs for each group. Proportion of NARCOs decreased from 0.18 at baseline to 0.12. Intervention group: Proportion increased from 0.10 at baseline to 0.29 using the GO-ARC Technique. Results were statistically significant. There was no decrease in the number of administrative controls generated by the intervention group. The Generating Options for Active Risk Control (GO-ARC) Technique appears to lead to more robust risk control options.

  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 (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. In this work, high-energy delayed γ-rays were demonstrated to be signatures for detection, identification, and quantification of special nuclear materials. Such γ-rays were measured in between linac pulses using independent data acquisition systems. A list-mode system was developed to measure low-energy delayed γ-rays after irradiation. Photofission product yields of 238U and 239Pu were determined based on the measured delayed γ-ray spectra. The differential yields of delayed γ-rays were also proven to be able to discriminate nuclear from non-nuclear materials. The measurement outcomes were compared with Monte Carlo simulation results. It was demonstrated that the current available codes have capabilities and limitations in the simulation of photofission process. A two

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

    International Nuclear Information System (INIS)

    Yang, Haori

    2016-01-01

    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. In this work, high-energy delayed γ-rays were demonstrated to be signatures for detection, identification, and quantification of special nuclear materials. Such γ-rays were measured in between linac pulses using independent data acquisition systems. A list-mode system was developed to measure low-energy delayed γ-rays after irradiation. Photofission product yields of 238 U and 239 Pu were determined based on the measured delayed γ-ray spectra. The differential yields of delayed γ-rays were also proven to be able to discriminate nuclear from non-nuclear materials. The measurement outcomes were compared with Monte Carlo simulation results. It was demonstrated that the current available codes have capabilities and limitations in the simulation of photofission process. A two-fold approach was

  2. Vibration reduction methods and techniques for rotorcraft utilizing on-blade active control, Phase I

    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...

  3. COMPARISON OF FREQUENCY RESPONSE AND NEURAL NETWORK TECHNIQUES FOR SYSTEM IDENTIFICATION OF AN ACTIVELY CONTROLLED STRUCTURE

    Directory of Open Access Journals (Sweden)

    DANIEL GÓMEZ PIZANO

    2011-01-01

    Full Text Available La identificación de sistemas es un método que puede ser utilizado para obtener las propiedades dinámicas de un sistema estructural integrado por sensores, actuadores yun algoritmo de control, sometido a diferentes tipos de excitación. Estas propiedades dinámicas son utilizadas en varios propósitos, tales como: Actualización de modelos, Monitoreo de salud estructural y Sistemas de control. En este artículo se presenta la identificación de una estructura con un sistema de control activo colocado en la parte superior por medio de la relación entre las señales de entrada (movimiento en la base y fuerza de control y la señal de salida (respuesta de la estructura. Para esto se utiliza la respuesta en frecuencia con funciones de transferencia y se compara con las relaciones no lineales obtenidas mediante Redes Neuronales Artificiales (RNA de una entrada-una salida (SISO y de múltiples entradas-una salida (MISO. Finalmente, se demuestra que la identificación del sistema estructural MISO con RNA presenta una mejor aproximación al sistema real que las obtenidas con la matriz de transferencia conformada a partir de funciones de transferencia.

  4. A novel control technique for active shunt power filters for aircraft applications

    OpenAIRE

    Lavopa, Elisabetta

    2011-01-01

    The More Electric Aircraft is a technological trend in modern aerospace industry to increasingly use electrical power on board the aircraft in place of mechanical, hydraulic and pneumatic power to drive aircraft subsystems. This brings major changes to the aircraft electrical system, increasing the complexity of the network topology together with stability and power quality issues. Shunt active power filters are a viable solution for power quality enhancement, in order to comply with the stan...

  5. Active technique by suction to control the flow structure over a van model

    Science.gov (United States)

    Harinaldi, Budiarso, Warjito, Kosasih, Engkos A.; Tarakka, Rustan; Simanungkalit, Sabar P.

    2012-06-01

    Today research trend in car aerodynamics are carried out from the point of view of the durable development. Some car companies have the objective to develop control solution that enable to reduce the aerodynamic drag of vehicle. It provides the possibility to modify the flow separation to reduce the development of the swirling structures around the vehicle. In this study, a family van is modeled with a modified form of Ahmed's body by changing the orientation of the flow from its original form (modified/reversed Ahmed Body). This model is equipped with a suction on the rear side to comprehensively examine the pressure field modifications that occur. The investigation combines computational and experimental work. The computational simulation used is k-epsilon flow turbulence model. The reversed Ahmed body used in the investigation has slant angle (φ) 35° at the front part. In the computational work, meshing type is tetra/hybrid element with hex core type and the grid number is more than 1.7 million in order to ensure detail discretization and more accurate calculation results. The boundary condition is upstream velocity of 11.1 m/s. Mean free stream at far upstream region is assumed in a steady state condition and uniform. The suction velocity is set at 1 m/s. Meanwhile in the experimental work a reversed Ahmed model is tested in a controlled wind tunnel experiments. The main measurement is the drag aerodynamic measurement at rear of the body of the model using strain gage. The results show that the application of a suction in the rear part of the van model give the effect of reducing the wake and the vortex is formed. Aerodynamic drag reduction close to 24% for the computational approach and 14.8% for the experimental approach by introducing a suction have been obtained.

  6. Statistical Techniques for Project Control

    CERN Document Server

    Badiru, Adedeji B

    2012-01-01

    A project can be simple or complex. In each case, proven project management processes must be followed. In all cases of project management implementation, control must be exercised in order to assure that project objectives are achieved. Statistical Techniques for Project Control seamlessly integrates qualitative and quantitative tools and techniques for project control. It fills the void that exists in the application of statistical techniques to project control. The book begins by defining the fundamentals of project management then explores how to temper quantitative analysis with qualitati

  7. Detection of active noise control on the standard motorcycle exhaust Supra X 125 D using PVC pipe technique form Y

    Science.gov (United States)

    Isranuri, I.; Alfisyahrin; Nasution, A. R.

    2018-02-01

    This detection aims to obtain noise reduction on the supra X 125D motorcycle exhaust by using the Active Noise Control Method. The technique is done using a Y-shaped PVC pipe to be bolted on the exhaust, which then branch Y PVC is placed loudspeaker with impermeable conditions. The function of this loudspeaker is as a secondary noise to counter the primary noise of the sound of exhaust motorcycle Supra X 125D. The sound generator in this study is the ISD 4004 module, which serves to generate noise to counter the source noise. How this ISD 4004 module works is by recording source noise then recording the source noise and then reversed the phase 180° by phase reversing circuit. So that, the noise generated by the sound generator will hit the source noise and encounter or such as addition of two different phase of sound will result in noise reduction when detected at the end of the Y-shaped PVC pipe. Inverted phase reversed using feed-back resistor 1 kΩ and 2 kΩ input resistors, 16V capacitor 2500μf and as amplifier using ICL 7660 and TL 702 CP. Test results on the highest 1000 rpm rotation engine speed on the Z axis of 2 dB, and at the highest 2000 rpm rotation engine speed also occurs on the Z axis of 1.5 dB.

  8. Techniques for active passivation

    Science.gov (United States)

    Roscioli, Joseph R.; Herndon, Scott C.; Nelson, Jr., David D.

    2016-12-20

    In one embodiment, active (continuous or intermittent) passivation may be employed to prevent interaction of sticky molecules with interfaces inside of an instrument (e.g., an infrared absorption spectrometer) and thereby improve response time. A passivation species may be continuously or intermittently applied to an inlet of the instrument while a sample gas stream is being applied. The passivation species may have a highly polar functional group that strongly binds to either water or polar groups of the interfaces, and once bound presents a non-polar group to the gas phase in order to prevent further binding of polar molecules. The instrument may be actively used to detect the sticky molecules while the passivation species is being applied.

  9. Tokamak impurity-control techniques

    International Nuclear Information System (INIS)

    Schmidt, J.A.

    1980-01-01

    A brief review is given of the impurity-control functions in tokamaks, their relative merits and disadvantages and some prominent edge-interaction-control techniques, and there is a discussion of a new proposal, the particle scraper, and its potential advantages. (author)

  10. Pilot study on the corrosion monitoring and control of the crude oil refining system by thin layer activation (TLA) technique

    International Nuclear Information System (INIS)

    Choochartchaikulkarn, Bodin; Chueinta, Siripone; Santawamaitre, Todsadol

    2001-01-01

    This report represents a pilot study on application of Ta technique for measurement monitoring the corrosion rates occurring in the refinery crude oil overhead crude oil system at the Bangchak Petroleum Co., Ltd. in Thailand during mid 1999 to mid 2000. TLA coupons containing very low activity of 5 6 Co produced by the accelerator was attached to the used electrical resistance probe inserted into production system at the test position. Gamma intensity of 56 Co was routinely monitored at external cladding and corrosion rates calculated in comparison with the non corroded standard after decay correction. From the study, TLA technique provides accurate corrosion rates less than 75 mm/year as compared to the standard Electrical Resistance Probes (ERP) technique. (author)

  11. Technique of nuclear reactors controls

    International Nuclear Information System (INIS)

    Weill, J.

    1953-12-01

    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) [fr

  12. Quality assurance techniques for activation analysis

    International Nuclear Information System (INIS)

    Becker, D.A.

    1984-01-01

    The principles and techniques of quality assurance are applied to the measurement method of activation analysis. Quality assurance is defined to include quality control and quality assessment. Plans for quality assurance include consideration of: personnel; facilities; analytical design; sampling and sample preparation; the measurement process; standards; and documentation. Activation analysis concerns include: irradiation; chemical separation; counting/detection; data collection, and analysis; and calibration. Types of standards discussed include calibration materials and quality assessment materials

  13. Journaling; an active learning technique.

    Science.gov (United States)

    Blake, Tim K

    2005-01-01

    Journaling is a method frequently discussed in nursing literature and educational literature as an active learning technique that is meant to enhance reflective practice. Reflective practice is a means of self-examination that involves looking back over what has happened in practice in an effort to improve, or encourage professional growth. Some of the benefits of reflective practice include discovering meaning, making connections between experiences and the classroom, instilling values of the profession, gaining the perspective of others, reflection on professional roles, and development of critical thinking. A review of theory and research is discussed, as well as suggestions for implementation of journaling into coursework.

  14. 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.

  15. 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)

    Montaya Martinez, T.; Zornoza Zornoza, A.; Granell Munoz, P.; Fayos, G.; Fajarddo, V.; Zorrilla, F.; Alonso Molina, J. L.; Morenilla Martinez, J. J.; Bernacer Bonora, I.; Martinez Francisco, F. J.

    2009-01-01

    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

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

    Science.gov (United States)

    Lai, Jih-Sheng; Liu, Changrong; Ridenour, Amy

    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.

  17. Modern insect control: Nuclear techniques and biotechnology

    International Nuclear Information System (INIS)

    1988-01-01

    The Symposium dealt primarily with genetic methods of insect control, including sterile insect technique (SIT), F 1 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 F 1 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

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

    International Nuclear Information System (INIS)

    Mukhammedov, S.; Khaydarov, A.; Pardaev, O.

    2013-01-01

    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)

  19. Applicability of statistical process control techniques

    NARCIS (Netherlands)

    Schippers, W.A.J.

    1998-01-01

    This paper concerns the application of Process Control Techniques (PCTs) for the improvement of the technical performance of discrete production processes. Successful applications of these techniques, such as Statistical Process Control Techniques (SPC), can be found in the literature. However, some

  20. fuzzy control technique fuzzy control technique applied to modified

    African Journals Online (AJOL)

    eobe

    epidemiological parameters) to the malaria model simulated by 9 fully ... The Mamdani controllers use a standard max-min inference process and a fast centre of min inference process and a ... Numerical results obtained using Matlab 2008a software software .... simulation environment using the 9 ODE Simulators. The test ...

  1. Modern control techniques for accelerators

    International Nuclear Information System (INIS)

    Goodwin, R.W.; Shea, M.F.

    1984-01-01

    Beginning in the mid to late sixties, most new accelerators were designed to include computer based control systems. Although each installation differed in detail, the technology of the sixties and early to mid seventies dictated an architecture that was essentially the same for the control systems of that era. A mini-computer was connected to the hardware and to a console. Two developments have changed the architecture of modern systems: the microprocessor and local area networks. This paper discusses these two developments and demonstrates their impact on control system design and implementation by way of describing a possible architecture for any size of accelerator. Both hardware and software aspects are included

  2. Research review: Indoor air quality control techniques

    International Nuclear Information System (INIS)

    Fisk, W.J.

    1986-10-01

    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

  3. Modern control techniques for accelerators

    International Nuclear Information System (INIS)

    Goodwin, R.W.; Shea, M.F.

    1984-05-01

    Beginning in the mid to late sixties, most new accelerators were designed to include computer based control systems. Although each installation differed in detail, the technology of the sixties and early to mid seventies dictated an architecture that was essentially the same for the control systems of that era. A mini-computer was connected to the hardware and to a console. Two developments have changed the architecture of modern systems: (a) the microprocessor and (b) local area networks. This paper discusses these two developments and demonstrates their impact on control system design and implementation by way of describing a possible architecture for any size of accelerator. Both hardware and software aspects are included

  4. Techniques of Ultrasound Cavitation Control

    Directory of Open Access Journals (Sweden)

    S. P. Skvortsov

    2015-01-01

    Full Text Available The control methods of ultrasonic cavitation applied now within the range from 20 kHz to 80 kHz use either control of ultrasound source parameters (amplitude, acoustic power, etc. or control of one of the cavitation effects (erosion of materials, sonoluminescence, power of acoustic noise, etc.. These methods provide effective management of technological processes, however, make it impossible to relate the estimated effect with parameters of pulsations of cavitation bubbles. This is, mainly, due to influence of a number of uncontrollable parameters, in particular, such as temperature, composition of liquid, gas content, etc. as well as because of the difficulty to establish interrelation between the estimated effect and parameters of pulsations. As a result, in most cases it is difficult to compare controlled parameters of ultrasonic cavitation among themselves, and quantitative characteristics of processes become depending on the type of ultrasonic installation and conditions of their measurement.In this regard, methods to determine parameters of bubble pulsations through sounding a cavitation area by low-intensity laser radiation or to record cavitation noise sub-harmonics reflecting dynamics of changing radius of cavitation bubbles are of interest. The method of optical sounding, via the analysis of spectral components of a scattered signal recorded by a photo-detector, allows us to define a phase of the bubbles collapse with respect to the sound wave and a moving speed of the bubbles wall, as well as to estimate a cavitation index within the light beam section.The method to record sub-harmonicas of cavitation noise allows us to define parameters of pulsations, average for cavitation areas.The above methods allow us both to study mechanisms of cavitation action and to form quantitative criteria of its efficiency based on the physical processes, rather than their consequences and are convenient for arranging a feedback in the units using

  5. Applications of neutron activation analysis technique

    International Nuclear Information System (INIS)

    Jonah, S. A.

    2000-07-01

    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 235 U 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

  6. Robust control technique for nuclear power plants

    International Nuclear Information System (INIS)

    Murphy, G.V.; Bailey, J.M.

    1989-03-01

    This report summarizes the linear quadratic Guassian (LQG) design technique with loop transfer recovery (LQG/LTR) for design of control systems. The concepts of return ratio, return difference, inverse return difference, and singular values are summarized. The LQG/LTR design technique allows the synthesis of a robust control system. To illustrate the LQG/LTR technique, a linearized model of a simple process has been chosen. The process has three state variables, one input, and one output. Three control system design methods are compared: LQG, LQG/LTR, and a proportional plus integral controller (PI). 7 refs., 20 figs., 6 tabs

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

    DEFF Research Database (Denmark)

    C. Swain, Kishore; Nørremark, Michael; Jørgensen, Rasmus Nyholm

    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 con......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 (Lehrstuhlfuer technische informatik) image processing library, iii) a laptop pc with the Linux OS. A 2...

  8. Pulsed neutron activation calibration technique

    International Nuclear Information System (INIS)

    Kehler, P.

    1979-01-01

    A pulsed neutron activation (PNA) for measurement of two-phase flow consists of a pulsed source of fast neutron to activate the oxygen in a steam-water mixture. Flow is measured downstream by an NaI detector. Measured counts are sorted by a multiscaler into different time channels. A counts vs. time distribution typical for two-phase flow with slip between the two phases is obtained. Proper evaluation for the counts/time distribution leads to flow-regime independent equations for the average of the inverse transil time and the average density. After calculation of the average mass flow velocity, the true mass flow is derived

  9. Characterizing Active Ingredients of eHealth Interventions Targeting Persons With Poorly Controlled Type 2 Diabetes Mellitus Using the Behavior Change Techniques Taxonomy: Scoping Review.

    Science.gov (United States)

    Kebede, Mihiretu M; Liedtke, Tatjana P; Möllers, Tobias; Pischke, Claudia R

    2017-10-12

    The behavior change technique taxonomy v1 (BCTTv1; Michie and colleagues, 2013) is a comprehensive tool to characterize active ingredients of interventions and includes 93 labels that are hierarchically clustered into 16 hierarchical clusters. The aim of this study was to identify the active ingredients in electronic health (eHealth) interventions targeting patients with poorly controlled type 2 diabetes mellitus (T2DM) and relevant outcomes. We conducted a scoping review using the BCTTv1. Randomized controlled trials (RCTs), studies with or pre-post-test designs, and quasi-experimental studies examining efficacy and effectiveness of eHealth interventions for disease management or the promotion of relevant health behaviors were identified by searching PubMed, Web of Science, and PsycINFO. Reviewers independently screened titles and abstracts for eligibility using predetermined eligibility criteria. Data were extracted following a data extraction sheet. The BCTTv1 was used to characterize active ingredients of the interventions reported in the included studies. Of the 1404 unique records screened, 32 studies fulfilled the inclusion criteria and reported results on the efficacy and or or effectiveness of interventions. Of the included 32 studies, 18 (56%) were Web-based interventions delivered via personal digital assistant (PDA), tablet, computer, and/or mobile phones; 7 (22%) were telehealth interventions delivered via landline; 6 (19%) made use of text messaging (short service message, SMS); and 1 employed videoconferencing (3%). Of the 16 hierarchical clusters of the BCTTv1, 11 were identified in interventions included in this review. Of the 93 individual behavior change techniques (BCTs), 31 were identified as active ingredients of the interventions. The most common BCTs identified were instruction on how to perform behavior, adding objects to the environment, information about health consequences, self-monitoring of the outcomes and/or and prefers to be

  10. mHealth Technologies to Influence Physical Activity and Sedentary Behaviors: Behavior Change Techniques, Systematic Review and Meta-Analysis of Randomized Controlled Trials.

    Science.gov (United States)

    Direito, Artur; Carraça, Eliana; Rawstorn, Jonathan; Whittaker, Robyn; Maddison, Ralph

    2017-04-01

    mHealth programs offer potential for practical and cost-effective delivery of interventions capable of reaching many individuals. To (1) compare the effectiveness of mHealth interventions to promote physical activity (PA) and reduce sedentary behavior (SB) in free-living young people and adults with a comparator exposed to usual care/minimal intervention; (2) determine whether, and to what extent, such interventions affect PA and SB levels and (3) use the taxonomy of behavior change techniques (BCTs) to describe intervention characteristics. A systematic review and meta-analysis following PRISMA guidelines was undertaken to identify randomized controlled trials (RCTs) comparing mHealth interventions with usual or minimal care among individuals free from conditions that could limit PA. Total PA, moderate-to-vigorous intensity physical activity (MVPA), walking and SB outcomes were extracted. Intervention content was independently coded following the 93-item taxonomy of BCTs. Twenty-one RCTs (1701 participants-700 with objectively measured PA) met eligibility criteria. SB decreased more following mHealth interventions than after usual care (standardised mean difference (SMD) -0.26, 95 % confidence interval (CI) -0.53 to -0.00). Summary effects across studies were small to moderate and non-significant for total PA (SMD 0.14, 95 % CI -0.12 to 0.41); MVPA (SMD 0.37, 95 % CI -0.03 to 0.77); and walking (SMD 0.14, 95 % CI -0.01 to 0.29). BCTs were employed more frequently in intervention (mean = 6.9, range 2 to 12) than in comparator conditions (mean = 3.1, range 0 to 10). Of all BCTs, only 31 were employed in intervention conditions. Current mHealth interventions have small effects on PA/SB. Technological advancements will enable more comprehensive, interactive and responsive intervention delivery. Future mHealth PA studies should ensure that all the active ingredients of the intervention are reported in sufficient detail.

  11. Operating control techniques for maglev transport systems

    Energy Technology Data Exchange (ETDEWEB)

    Kraft, K H; Schnieder, E

    1984-06-01

    The technical and operational possibilities of magnetic levitation transport systems can only be fully exploited by introducing 'intelligent' control systems which ensure automatic and trouble-free train running. The solution of exacting requirements in the fields of traction dynamics, security and control as well as information gathering transmission and processing is an important prior condition in that respect. The authors report here on the present state of research and development in operating control techniques applicable to maglev transport systems.

  12. 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

  13. Selective weed control using laser techniques

    OpenAIRE

    Marx, Christian; Pastrana-Perez, Julio; Hustedt, Michael; Barcikowski, Stephan; Haferkamp, Heinz; Rath, Thomas

    2012-01-01

    This contribution discusses technical and growth relevant aspects of using laser techniques for weed control. The research on thermal weed control via laser first focused on the interaction of laser beams and weed plants. Due to preliminary studies, a CO2-laser was selected for further studies with regard to the process factors laser energy, laser spot area, coverage of the weeds meristem, weed species (Amaranthus retroflexus), and weed growth stage. Thereby, the laser damage was modeled in o...

  14. Myoelectric Control Techniques for a Rehabilitation Robot

    Directory of Open Access Journals (Sweden)

    Alan Smith

    2011-01-01

    Full Text Available This work examines two different types of myoelectric control schemes for the purpose of rehabilitation robot applications. The first is a commonly used technique based on a Gaussian classifier. It is implemented in real time for healthy subjects in addition to a subject with Central Cord Syndrome (CCS. The myoelectric control scheme is used to control three degrees of freedom (DOF on a robot manipulator which corresponded to the robot's elbow joint, wrist joint, and gripper. The classes of motion controlled include elbow flexion and extension, wrist pronation and supination, hand grasping and releasing, and rest. Healthy subjects were able to achieve 90% accuracy. Single DOF controllers were first tested on the subject with CCS and he achieved 100%, 96%, and 85% accuracy for the elbow, gripper, and wrist controllers respectively. Secondly, he was able to control the three DOF controller at 68% accuracy. The potential applications for this scheme are rehabilitation and teleoperation. To overcome limitations in the pattern recognition based scheme, a second myoelectric control scheme is also presented which is trained using electromyographic (EMG data derived from natural reaching motions in the sagittal plane. This second scheme is based on a time delayed neural network (TDNN which has the ability to control multiple DOF at once. The controller tracked a subject's elbow and shoulder joints in the sagittal plane. Results showed an average error of 19° for the two joints. This myoelectric control scheme has the potential of being used in the development of exoskeleton and orthotic rehabilitation applications.

  15. Use of nuclear techniques in biological control

    International Nuclear Information System (INIS)

    Greany, Patrick D.; Carpenter, James E.

    2000-01-01

    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

  16. Multidisciplinary Techniques and Novel Aircraft Control Systems

    Science.gov (United States)

    Padula, Sharon L.; Rogers, James L.; Raney, David L.

    2000-01-01

    The Aircraft Morphing Program at NASA Langley Research Center explores opportunities to improve airframe designs with smart technologies. Two elements of this basic research program are multidisciplinary design optimization (MDO) and advanced flow control. This paper describes examples where MDO techniques such as sensitivity analysis, automatic differentiation, and genetic algorithms contribute to the design of novel control systems. In the test case, the design and use of distributed shape-change devices to provide low-rate maneuvering capability for a tailless aircraft is considered. The ability of MDO to add value to control system development is illustrated using results from several years of research funded by the Aircraft Morphing Program.

  17. Application of PQR Theory for control of a 3-phase 4-wire 4-legs shunt active power filter in the aß?-axes using 3D-SVM technique

    Directory of Open Access Journals (Sweden)

    Ali CHEBABHI

    2015-05-01

    Full Text Available This article discusses and compares two control strategies applied to a 3-phase 4-wire 4-leg shunt active power filter. These two control strategies, including the cross-vector theory called CV theory and the direct method called PQR theory, are based on the instantaneous control of active and reactive power. On one hand, it is shown that, in some cases, cross-vector theory requires elimination of the zero sequence currents in a 3-phase 4-wire 4-leg shunt active power filter, which needs a power storage element, and on the other hand pretreatment system voltage is necessary to obtain compensated sinusoidal current and a degree of freedom. By relying on the cross-vector theory, the PQR theory is used to extract and remove harmonic currents components. In this control technique, there are two internal current control loops and an external voltage control loop, these control loops have been realized by PI controllers when applied 3D-SVM of switching technique. We choose as criteria for comparison the transient and the Total Harmonic Distortion in the line current. A series of simulations in MATLAB/ Simulink environment have been presented and discussed to show the performance of the two control strategies.

  18. Theory-based interventions combining mental simulation and planning techniques to improve physical activity: Null results from two randomized controlled trials

    Directory of Open Access Journals (Sweden)

    Carine Meslot

    2016-11-01

    Full Text Available Interventions to assist individuals in initiating and maintaining regular participation in physical activity are not always effective. Psychological and behavioural theories advocate the importance of both motivation and volition in interventions to change health behaviour. Interventions adopting self-regulation strategies that foster motivational and volitional components may, therefore, have utility in promoting regular physical activity participation. We tested the efficacy of an intervention adopting motivational (mental simulation and volitional (implementation intentions components to promote a regular physical activity in two studies. Study 1 adopted a cluster randomised design students in which participants (n=92 were allocated to one of three conditions: mental simulation plus implementation intention, implementation intention only, or control. Study 2 adopted a 2 (mental simulation vs. no mental simulation x 2 (implementation intention vs. no implementation intention randomised controlled design in which fitness centre attendees (n=184 were randomly allocated one of four conditions: mental simulation only, implementation intention only, combined, or control. Physical activity behaviour was measured by self-report (Study 1 or fitness centre attendance (Study 2 at 4- (Studies 1 and 2 and 19- (Study 2 only week follow-up periods. Findings revealed no statistically significant main or interactive effects of the mental simulation and implementation intention conditions on physical activity outcomes in either study. Despite adopting protocols consistent with previous research, utilizing objective behavioural measures, and having sufficient statistical power, results provide evidence that, in contrast to previous findings, the motivational and volitional components are not effective in changing physical activity behaviour. Future research should focus on the format of the intervention components, test the effects of each component alone and

  19. 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...

  20. 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.

  1. Advanced instrumentation and control techniques for nuclear power plants

    International Nuclear Information System (INIS)

    Hayakawa, Hiroyasu; Makino, Maomi

    1989-01-01

    Toshiba has been promoting the development and improvement of control and instrumentation (C and I) systems employing the latest technologies, to fulfill the requirements of nuclear power plants for increased reliability, the upgrading of functions, improved maintainability, and reasonable cost. Such development has been systematically performed based on a schematic view of integrated digital control and instrumentation systems, actively adopting state-of-the-art techniques such as the latest man-machine interfaces, digital and optical multiplexing techniques, and artificial intelligence. In addition, comprehensive feedback has been obtained from the accumulation of operating experience. This paper describes the purpose, contents and status of applications of representative newly-developed systems. (author)

  2. Beam Techniques - Beam Control and Manipulation

    International Nuclear Information System (INIS)

    Minty, Michiko G

    2003-01-01

    We describe commonly used strategies for the control of charged particle beams and the manipulation of their properties. Emphasis is placed on relativistic beams in linear accelerators and storage rings. After a brief review of linear optics, we discuss basic and advanced beam control techniques, such as transverse and longitudinal lattice diagnostics, matching, orbit correction and steering, beam-based alignment, and linac emittance preservation. A variety of methods for the manipulation of particle beam properties are also presented, for instance, bunch length and energy compression, bunch rotation, changes to the damping partition number, and beam collimation. The different procedures are illustrated by examples from various accelerators. Special topics include injection and extraction methods, beam cooling, spin transport and polarization

  3. Beam Techniques - Beam Control and Manipulation

    Energy Technology Data Exchange (ETDEWEB)

    Minty, Michiko G

    2003-04-24

    We describe commonly used strategies for the control of charged particle beams and the manipulation of their properties. Emphasis is placed on relativistic beams in linear accelerators and storage rings. After a brief review of linear optics, we discuss basic and advanced beam control techniques, such as transverse and longitudinal lattice diagnostics, matching, orbit correction and steering, beam-based alignment, and linac emittance preservation. A variety of methods for the manipulation of particle beam properties are also presented, for instance, bunch length and energy compression, bunch rotation, changes to the damping partition number, and beam collimation. The different procedures are illustrated by examples from various accelerators. Special topics include injection and extraction methods, beam cooling, spin transport and polarization.

  4. Nuclear activation techniques in the life sciences

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1978-08-15

    The analysis of the elemental composition of biological materials is presently undertaken on a large scale in many countries around the world One recent estimate puts the number of such analyses at six thousand million single-element determinations per year, of which about sixteen million are for the so-called trace elements. Since many of these elements are known to play an important role in relation to health and disease, there is considerable interest in learning more about the ways in which they function in living organisms. Nuclear activation techniques, generally referred to collectively as 'activation analysis' constitute an important group of methods for the analysis of the elemental composition of biological materials. Generally they rely on the use of a research nuclear reactor as a source of neutrons for bombarding small samples of biological material, followed by a measurement of the induced radioactivity to provide an estimate of the concentrations of elements. Other methods of activation with Bremsstrahlung and charged particles may also be used, and have their own special applications. These methods of in vitro analysis are particularly suitable for the study of trace elements. Another important group of methods makes use of neutrons from isotopic neutron sources or neutron generators to activate the whole body, or a part of the body, of a living patient. They are generally used for the study of major elements such as Ca, Na and N. All these techniques have previously been the subject of two symposia organised by the IAEA in 1967 and 1972. The present meeting was held to review some of the more recent developments in this field and also to provide a viewpoint on the current status of nuclear activation techniques vis-a-vis other competing non-nuclear methods of analysis.

  5. Artificial intelligence techniques for voltage control

    Energy Technology Data Exchange (ETDEWEB)

    Ekwue, A.; Cheng, D.T.Y.; Macqueen, J.F.

    1997-12-31

    In electric power systems, the advantages of reactive power dispatching or optimisation include improved utilisation of reactive power sources and hence reduction in reactive power flows and real losses of the system; unloading of the system and equipment as a result of reactive flow reduction; the power factors of generation are improved and system security is enhanced; reduced voltage gradients and somewhat higher voltages which result across the system from improved operation; deferred capital investment is new reactive power sources as a result of improved utilisation of existing equipment; and for the National Grid Company plc (NGC), the main advantage is reduced out-of-merit operation. The problem of reactive power control has been studied and widely reported in the literature. Non-linear programming methods as well as linear programming techniques for constraint dispatch have been described. Static optimisation of reactive power sources by the use of sensitivity analysis was described by Kishore and Hill. Long range optimum var planning has been considered and the optimum amount and location of network reactive compensation so as to maintain the system voltage within the desired limits, while operating under normal and various insecurity states, have also been studied using several methods. The objective of this chapter is therefore to review conventional methods as well as AI techniques for reactive power control. (Author)

  6. Balancing Training Techniques for Flight Controller Certification

    Science.gov (United States)

    Gosling, Christina

    2011-01-01

    Training of ground control teams has been a difficult task in space operations. There are several intangible skills that must be learned to become the steely eyed men and women of mission control who respond to spacecraft failures that can lead to loss of vehicle or crew if handled improperly. And as difficult as training is, it can also be costly. Every day, month or year an operator is in training, is a day that not only they are being trained without direct benefit to the organization, but potentially an instructor or mentor is also being paid for hours spent assisting them. Therefore, optimization of the training flow is highly desired. Recently the Expedition Division (DI) at Johnson Space Flight Center has recreated their training flows for the purpose of both moving to an operator/specialist/instructor hierarchy and to address past inefficiencies in the training flow. This paper will discuss the types of training DI is utilizing in their new flows, and the balance that has been struck between the ideal learning environments and realistic constraints. Specifically, the past training flow for the ISS Attitude Determination and Control Officer will be presented, including drawbacks that were encountered. Then the new training flow will be discussed and how a new approach utilizes more training methods and teaching techniques. We will look at how DI has integrated classes, workshops, checkouts, module reviews, scenarios, OJT, paper sims, Mini Sims, and finally Integrated Sims to balance the cost and timing of training a new flight controller.

  7. Active control of the noise

    International Nuclear Information System (INIS)

    Rodriguez V, Luis Alfonso; Lopez Q, Jose German

    2001-01-01

    The problems of acoustic noise are more and more preponderant in the measure in that the amount of equipment and industrial machinery is increased such as fans, transformers, compressors etc. the use of devices passive mechanics for the reduction of the noise is effective and very appreciated because its effects embrace a wide range of acoustic frequency. However, to low frequencies, such devices become too big and expensive besides that present a tendency to do not effective. The control of active noise, CAN, using the electronic generation anti-noise, constitutes an interesting solution to the problem because their operation principle allows achieving an appreciable reduction of the noise by means of the use of compact devices. The traditional techniques for the control of acoustic noise like barriers and silenced to attenuate it, are classified as passive and their works has been accepted as norm as for the treatment of problems of noise it refers. Such techniques are considered in general very effective in the attenuation of noise of wide band. However, for low frequency, the required passive structures are too big and expensive; also, their effectiveness diminishes flagrantly, that which makes them impractical in many applications. The active suppression is profiled like a practical alternative for the reduction of acoustic noise. The idea in the active treatment of the noise it contemplates the use of a device electro-acoustic, like a speaker for example that it cancels to the noise by the generation of sounds of Same width and of contrary phase (anti-noise). The cancellation phenomenon is carried out when the ant-noise combines acoustically with the noise, what is in the cancellation of both sounds. The effectiveness of the cancellation of the primary source of noise depends on the precision with which the width and the phase of the generated ant-noise are controlled. The active control of noise, ANC (activates noise control), it is being investigated for

  8. Supersonic impinging jet noise reduction using a hybrid control technique

    Science.gov (United States)

    Wiley, Alex; Kumar, Rajan

    2015-07-01

    Control of the highly resonant flowfield associated with supersonic impinging jet has been experimentally investigated. Measurements were made in the supersonic impinging jet facility at the Florida State University for a Mach 1.5 ideally expanded jet. Measurements included unsteady pressures on a surface plate near the nozzle exit, acoustics in the nearfield and beneath the impingement plane, and velocity field using particle image velocimetry. Both passive control using porous surface and active control with high momentum microjet injection are effective in reducing nearfield noise and flow unsteadiness over a range of geometrical parameters; however, the type of noise reduction achieved by the two techniques is different. The passive control reduces broadband noise whereas microjet injection attenuates high amplitude impinging tones. The hybrid control, a combination of two control methods, reduces both broadband and high amplitude impinging tones and surprisingly its effectiveness is more that the additive effect of the two control techniques. The flow field measurements show that with hybrid control the impinging jet is stabilized and the turbulence quantities such as streamwise turbulence intensity, transverse turbulence intensity and turbulent shear stress are significantly reduced.

  9. State and data techniques for control of discontinuous systems

    International Nuclear Information System (INIS)

    Kisner, R.A.

    1986-01-01

    This paper describes a technique for structured analysis and design of automated control systems. The technique integrates control of continuous and discontinuous nuclear power plant subsystems and components. A hierarchical control system with distributed intelligence follows from applying the technique. Further, it can be applied to all phases of control system design. For simplicity, the example used in the paper is limited to phase 1 design (basic automatic control action), in which no maintenance, testing, or contingency capability is attempted. 11 figs

  10. Decentralized control using compositional analysis techniques

    NARCIS (Netherlands)

    Kerber, F.; van der Schaft, A. J.

    2011-01-01

    Decentralized control strategies aim at achieving a global control target by means of distributed local controllers acting on individual subsystems of the overall plant. In this sense, decentralized control is a dual problem to compositional analysis where a global verification task is decomposed

  11. The colloquial approach: An active learning technique

    Science.gov (United States)

    Arce, Pedro

    1994-09-01

    This paper addresses the very important problem of the effectiveness of teaching methodologies in fundamental engineering courses such as transport phenomena. An active learning strategy, termed the colloquial approach, is proposed in order to increase student involvement in the learning process. This methodology is a considerable departure from traditional methods that use solo lecturing. It is based on guided discussions, and it promotes student understanding of new concepts by directing the student to construct new ideas by building upon the current knowledge and by focusing on key cases that capture the essential aspects of new concepts. The colloquial approach motivates the student to participate in discussions, to develop detailed notes, and to design (or construct) his or her own explanation for a given problem. This paper discusses the main features of the colloquial approach within the framework of other current and previous techniques. Problem-solving strategies and the need for new textbooks and for future investigations based on the colloquial approach are also outlined.

  12. Technique of nuclear reactors controls; Technique des controles des reacteurs nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Weill, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1953-12-15

    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) [French] Nous avons aborde le probleme de la ''Technique du Controle des reacteurs nucleaires'' dans le but de realiser le controle du reacteur de Saclay. C'est ainsi que nous avons ete amene a etudier le probleme dans son ensemble, tel qu'il se pose pour tout reacteur a uranium naturel. Ce travail traite principalement du domaine des mesures a caractere nucleaire et s'etend dans le domaine des mesures thermodynamque de niveaux, etc... mettant en relief les caracteristiques nouvelles exigees de la part des detecteurs du fait de leur utilisation dans le flux de neutrons thermiques. Dans le domaine de mesures nucleaires, nous indiquons principalement les realisations et les resultats obtenus pour les detecteurs de neutrons thermiques et pour la mesure de courants d'ionisations. Nous traitons egalement du probleme technique du demarrage d'un reacteur et du probleme de la mesure de la reactivite. Nous donnons les details necessaires a la comrehension de tous les schemas et plans de cablages essentiels mis au point, en particulier, pour le reacteur de Saclay. (auteur)

  13. Active neutron technique for detecting attempted special nuclear material diversion

    International Nuclear Information System (INIS)

    Smith, G.W.; Rice, L.G. III.

    1979-01-01

    The identification of special nuclear material (SNM) diversion is necessary if SNM inventory control is to be maintained at nuclear facilities. (Special nuclear materials are defined for this purpose as either 235 U of 239 Pu.) Direct SNM identification by the detection of natural decay or fission radiation is inadequate if the SNM is concealed by appropriate shielding. The active neutron interrogation technique described combines direct SNM identification by delayed fission neutron (DFN) detection with implied SNM detection by the identification of materials capable of shielding SNM from direct detection. This technique is being developed for application in an unattended material/equipment portal through which items such as electronic instruments, packages, tool boxes, etc., will pass. The volume of this portal will be 41-cm wide, 53-cm high and 76-cm deep. The objective of this technique is to identify an attempted diversion of at least 20 grams of SNM with a measurement time of 30 seconds

  14. 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).

  15. 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.

  16. Multivariable Techniques for High-Speed Research Flight Control Systems

    Science.gov (United States)

    Newman, Brett A.

    1999-01-01

    This report describes the activities and findings conducted under contract with NASA Langley Research Center. Subject matter is the investigation of suitable multivariable flight control design methodologies and solutions for large, flexible high-speed vehicles. Specifically, methodologies are to address the inner control loops used for stabilization and augmentation of a highly coupled airframe system possibly involving rigid-body motion, structural vibrations, unsteady aerodynamics, and actuator dynamics. Design and analysis techniques considered in this body of work are both conventional-based and contemporary-based, and the vehicle of interest is the High-Speed Civil Transport (HSCT). Major findings include: (1) control architectures based on aft tail only are not well suited for highly flexible, high-speed vehicles, (2) theoretical underpinnings of the Wykes structural mode control logic is based on several assumptions concerning vehicle dynamic characteristics, and if not satisfied, the control logic can break down leading to mode destabilization, (3) two-loop control architectures that utilize small forward vanes with the aft tail provide highly attractive and feasible solutions to the longitudinal axis control challenges, and (4) closed-loop simulation sizing analyses indicate the baseline vane model utilized in this report is most likely oversized for normal loading conditions.

  17. ACTIVE CYCLE BREATHING TECHNIQUES IN HEART FAILURE ...

    African Journals Online (AJOL)

    RICHY

    Pulmonary Function Responses to Active Cycle. Breathing ... Key Words: Heart Failure, Active Cycle of Breathing ... cough, fatigue, reduced respiratory muscle mass, and. [5] ... an amount of exercise which is said to lower disease. [9].

  18. 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...

  19. 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.

  20. 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....

  1. Effectiveness of radon control techniques in fifteen homes

    International Nuclear Information System (INIS)

    Turk, B.H.; Prill, R.J.; Fisk, W.J.; Grimsrud, D.T.; Sextro, R.G.

    1991-01-01

    Radon control systems were installed and evaluated in fourteen homes in the Spokane River Valley/Rathdrum Prairie and in one home in Vancouver, Washington. Because of local soil conditions, subsurface ventilation (SSV) by pressurization was always more effective in these houses than SSV by depressurization in reducing indoor radon levels to below guidelines. Basement overpressurization was successfully applied in five houses with airtight basements where practical-sized fans could develop an overpressure of 1 to 3 Pascals. Crawlspace ventilation was more effective than crawlspace isolation in reducing radon entry from the crawlspace, but had to be used in conjunction with other mitigation techniques, from the crawlspace, but had to be used in conjunction with other mitigation techniques, since the houses also had basements. Indoor radon concentrations in two houses with air-to-air heat exchangers (AAHX) were reduced to levels inversely dependent on the new total ventilation rates and were lowered even further in one house where the air distribution system was modified. Sealing penetrations in the below-grade surfaces of substructures was relatively ineffective in controlling radon. Operation of the radon control systems (except for the AAHX's) made no measurable change in ventilation rates or indoor concentrations of other measured pollutants. Installation costs ranged from approximately $4/m 2 for sealing to $28/m 2 for the AAHXs. Annual operating costs for the active systems were estimated to be approximately $60 to $170

  2. Aseptic minimum volume vitrification technique for porcine parthenogenetically activated blastocyst.

    Science.gov (United States)

    Lin, Lin; Yu, Yutao; Zhang, Xiuqing; Yang, Huanming; Bolund, Lars; Callesen, Henrik; Vajta, Gábor

    2011-01-01

    Minimum volume vitrification may provide extremely high cooling and warming rates if the sample and the surrounding medium contacts directly with the respective liquid nitrogen and warming medium. However, this direct contact may result in microbial contamination. In this work, an earlier aseptic technique was applied for minimum volume vitrification. After equilibration, samples were loaded on a plastic film, immersed rapidly into factory derived, filter-sterilized liquid nitrogen, and sealed into sterile, pre-cooled straws. At warming, the straw was cut, the filmstrip was immersed into a 39 degree C warming medium, and the sample was stepwise rehydrated. Cryosurvival rates of porcine blastocysts produced by parthenogenetical activation did not differ from control, vitrified blastocysts with Cryotop. This approach can be used for minimum volume vitrification methods and may be suitable to overcome the biological dangers and legal restrictions that hamper the application of open vitrification techniques.

  3. Analog techniques in CEBAF's RF control system

    International Nuclear Information System (INIS)

    Hovater, C.; Fugitt, J.

    1989-01-01

    Recent developments in high-speed analog technology have progressed into the areas of traditional RF technology. Diode related devices are being replaced by analog IC's in the CEBAF RF control system. Complex phase modulators and attenuators have been successfully tested at 70 MHz. They have three advantages over existing technology: lower cost, less temperature sensitivity, and more linearity. RF signal conditioning components and how to implement the new analog IC's will be covered in this paper. 4 refs., 5 figs

  4. Analog techniques in CEBAF'S RF control system

    International Nuclear Information System (INIS)

    Hovater, C.; Fugitt, J.

    1989-01-01

    Recent developments in high-speed analog technology have progressed into the areas of traditional rf technology. Diode-related devices are being replaced by analog IC's in the CEBAF rf control system. Complex phase modulators and attenuators have been successfully tested at 70 MHz. They have three advantages over existing technology: lower cost, less temperature sensitivity, and more linearity. Rf signal conditioning components and how to implement the new analog IC's will be covered in this paper. 4 refs., 5 figs

  5. Development of NSTX Particle Control Techniques

    International Nuclear Information System (INIS)

    Kugel, H.W.; Maingi, R.; Bell, M.; Gates, D.; Hill, K.; LeBlanc, B.; Mueller, D.; Kaita, R.; Paul, S.; Sabbagh, S.; Skinner, C.H.; Soukhanovskii, V.; Stratton, B.; Raman, R.

    2004-01-01

    The National Spherical Torus Experiment (NSTX) High Harmonic Fast Wave (HHFW) current-drive discharges will require density control for acceptable efficiency. In NSTX, this involves primarily controlling impurity influxes and recycling. We have compared boronization on hot and cold surfaces, varying helium glow discharge conditioning (HeGDC) durations, helium discharge cleaning, brief daily boronization, and between discharge boronization to reduce and control spontaneous density rises. Access to Ohmic H-modes was enabled by boronization on hot surfaces, however, the duration of the effectiveness of hot and cold boronization was comparable. A 15 minute HeGDC between discharges was needed for reproducible L-H transitions. Helium discharge conditioning yielded slower density rises than 15 minutes of HeGDC. Brief daily boronization followed by a comparable duration of applied HeGDC restored and enhanced good conditions. Additional brief boronizations between discharges did not improve plasma performance (reduced recycling, reduced impurity luminosities, earlier L-H transitions, longer plasma current flattops, higher stored energies) if conditions were already good. Between discharge boronization required increases in the NSTX duty cycle due to the need for additional HeGDC to remove codeposited D

  6. Contributions to fuzzy polynomial techniques for stability analysis and control

    OpenAIRE

    Pitarch Pérez, José Luis

    2014-01-01

    The present thesis employs fuzzy-polynomial control techniques in order to improve the stability analysis and control of nonlinear systems. Initially, it reviews the more extended techniques in the field of Takagi-Sugeno fuzzy systems, such as the more relevant results about polynomial and fuzzy polynomial systems. The basic framework uses fuzzy polynomial models by Taylor series and sum-of-squares techniques (semidefinite programming) in order to obtain stability guarantees...

  7. Activities at Forschungszentrum Juelich in Safeguards Analytical Techniques and Measurements

    International Nuclear Information System (INIS)

    Duerr, M.; Knott, A.; Middendorp, R.; Niemeyer, I.; Kueppers, S.; Zoriy, M.; Froning, M.; Bosbach, D.

    2015-01-01

    The application of safeguards by the IAEA involves analytical measurements of samples taken during inspections. The development and advancement of analytical techniques with support from the Member States contributes to strengthened and more efficient verification of compliance with non-proliferation obligations. Since recently, a cooperation agreement has been established between Forschungszentrum Juelich and the IAEA in the field of analytical services. The current working areas of Forschungszentrum Juelich are: (i) Production of synthetic micro-particles as calibration standard and reference material for particle analysis, (ii) qualification of the Forschungszentrum Juelich as a member of the IAEA network of analytical laboratories for safeguards (NWAL), and (iii) analysis of impurities in nuclear material samples. With respect to the synthesis of particles, a dedicated setup for the production of uranium particles is being developed, which addresses the urgent need for material tailored for its use in quality assurance and quality control measures for particle analysis of environmental swipe samples. Furthermore, Forschungszentrum Juelich has been nominated as a candidate laboratory for membership in the NWAL network. To this end, analytical capabilities at Forschungszentrum Juelich have been joined to form an analytical service within a dedicated quality management system. Another activity is the establishment of analytical techniques for impurity analysis of uranium-oxide, mainly focusing on inductively coupled mass spectrometry. This contribution will present the activities at Forschungszentrum Juelich in the area of analytical measurements and techniques for nuclear verification. (author)

  8. Modeling and control of active twist aircraft

    Science.gov (United States)

    Cramer, Nicholas Bryan

    The Wright Brothers marked the beginning of powered flight in 1903 using an active twist mechanism as their means of controlling roll. As time passed due to advances in other technologies that transformed aviation the active twist mechanism was no longer used. With the recent advances in material science and manufacturability, the possibility of the practical use of active twist technologies has emerged. In this dissertation, the advantages and disadvantages of active twist techniques are investigated through the development of an aeroelastic modeling method intended for informing the designs of such technologies and wind tunnel testing to confirm the capabilities of the active twist technologies and validate the model. Control principles for the enabling structural technologies are also proposed while the potential gains of dynamic, active twist are analyzed.

  9. State and data techniques for control of discontinuous systems

    International Nuclear Information System (INIS)

    Kisner, R.A.

    1986-01-01

    The need for automated control systems becomes clear as the complexity of nuclear power plants increases and economic incentives demand higher plant availability. A control system with intelligence distributed throughout its controllers allows reduction in operator workload, perhaps reduction in crew size, and potentially a reduction in on-line human error. In automated systems of this kind, each controller should be capable of making decisions and carrying out a plan of action. This paper describes a technique for structured analysis and design of automated control systems. The technique integrates control of continuous and discontinuous nuclear power plant subsystems and components. A hierarchical control system with distributed intelligence follows from applying the technique. Further, it can be applied to all phases of control system design. For simplicity, the example used in the paper is limited to phase I design (basic automatic control action), in which no maintenance, testing, or contingency capability is attempted

  10. Suitable activated carbon-13 tracer techniques

    International Nuclear Information System (INIS)

    Zhang Weicheng; Peng Xiuru; Wang Yuhua

    1995-12-01

    Feasibility and applicability studies of the proton induced gamma ray emission (PIGE) have been performed. The graphite was firstly bombarded at various proton energies to determine gamma ray yield (and, thus, sensitivities) for the reaction of interest. The accuracy for the determination of 13 C abundance was checked, and the precision with which this value and ratios 13 C/ 12 C may be obtained was established by repetitive analysis samples. The performance of different standards in this determination was assessed. The mathematical treatment was developed for the determination of 13 C abundance in tracer studies, and to derive the equations that govern this method of analysis from first principles, to arrive finally at a simple expression by virtue of the observed regularities. The system was calibrated by measuring the gamma ray yield form the 12 C (p, γ) 13 N and 13 C(p,γ) 14 N reaction as a function of known 13 C enrichment. Using this experimentally determined calibration curve, unknown materials can be assayed. This technique is applicable to the analysis of samples with 13 C enrichments between 0.1% and 90%. The samples of human breath natural samples were analyzed against graphite and Cylinder CO 2 standards. Relative standard deviations were 13 C abundance, an increase in 13 C per cent isotopic abundance from the natural 1.11% (average) to only 1.39% may be ascertained. Finally, PIGE is compared with more classical techniques for analysis of 13 C tracer experiments. Ease and speed are important advantages of this technique over mass spectrometry, and its error is compatible with the natural variation of biological results. (9 refs., 11 figs., 9 tabs.)

  11. Application of activation techniques to biological analysis

    International Nuclear Information System (INIS)

    Bowen, H.J.M.

    1981-01-01

    Applications of activation analysis in the biological sciences are reviewed for the period of 1970 to 1979. The stages and characteristics of activation analysis are described, and its advantages and disadvantages enumerated. Most applications involve activation by thermal neutrons followed by either radiochemical or instrumental determination. Relatively little use has been made of activation by fast neutrons, photons, or charged particles. In vivo analyses are included, but those based on prompt gamma or x-ray emission are not. Major applications include studies of reference materials, and the elemental analysis of plants, marine biota, animal and human tissues, diets, and excreta. Relatively little use of it has been made in biochemistry, microbiology, and entomology, but it has become important in toxicology and environmental science. The elements most often determined are Ag, As, Au, Br, Ca, Cd, Cl, Co, Cr, Cs, Cu, Fe, Hg, I, K, Mn, Mo, Na, Rb, Sb, Sc, Se, and Zn, while few or no determinations of B, Be, Bi, Ga, Gd, Ge, H, In, Ir, Li, Nd, Os, Pd, Pr, Pt, Re, Rh, Ru, Te, Tl, or Y have been made in biological materials

  12. Respirometry techniques and activated sludge models

    NARCIS (Netherlands)

    Benes, O.; Spanjers, H.; Holba, M.

    2002-01-01

    This paper aims to explain results of respirometry experiments using Activated Sludge Model No. 1. In cases of insufficient fit of ASM No. 1, further modifications to the model were carried out and the so-called "Enzymatic model" was developed. The best-fit method was used to determine the effect of

  13. Opportunities to Create Active Learning Techniques in the Classroom

    Science.gov (United States)

    Camacho, Danielle J.; Legare, Jill M.

    2015-01-01

    The purpose of this article is to contribute to the growing body of research that focuses on active learning techniques. Active learning techniques require students to consider a given set of information, analyze, process, and prepare to restate what has been learned--all strategies are confirmed to improve higher order thinking skills. Active…

  14. 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.

  15. Laser and infrared techniques for water pollution control

    International Nuclear Information System (INIS)

    Geraci, A.L.; Landolina, F.; Pantani, L.; Cecchi, G.

    1993-01-01

    A remote sensing application for the control of oil pollution and water quality was developed by the National Council of Research at Florence, and the University of Catania, both in Italy. The application is based on the simultaneous use of active antipassive remote sensing systems (lidar and flir systems) from a helicopter. Water pollution characteristics were determined with the lidar system, in polluted areas of water detected, on a larger scale, by the flir system. Pollution characteristics detected included type of pollutant, type of oil, and oil thickness. The experiment, named LIRA, was carried out using an Italian Navy helicopter over sea areas around Sicily having a high risk of pollution. The results proved the effectiveness and usefulness of the techniques proposed

  16. 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.

  17. Control of nucleus accumbens activity with neurofeedback.

    Science.gov (United States)

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

    2014-08-01

    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 presented as "neurofeedback." In an fMRI-based neurofeedback experiment designed to elicit NAcc activity, we found that subjects could increase their own NAcc activity, and that display of neurofeedback significantly enhanced their ability to do so. Subjects were not as capable of decreasing their NAcc activity, however, and enhanced control did not persist after subsequent removal of neurofeedback. Further analyses suggested that individuals who recruited positive aroused affect were better able to increase NAcc activity in response to neurofeedback, and that NAcc neurofeedback also elicited functionally correlated activity in the medial prefrontal cortex. Together, these findings suggest that humans can modulate their own NAcc activity and that fMRI-based neurofeedback may augment their efforts. The observed association between positive arousal and effective NAcc control further supports an anticipatory affect account of NAcc function. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Synchronization of Rikitake chaotic attractor using active control

    International Nuclear Information System (INIS)

    Vincent, U.E.

    2005-01-01

    Using synchronization technique based on control theory, we design an active controller which enables the synchronization of two identical Rikitake two-disc dynamo systems. Numerical simulations are used to show the robustness of the active control scheme in synchronizing coupled Rikitake dynamical systems. On the sequential application of the active control, transitions from temporary phase locking (TPL) state to complete synchronization state were found

  19. Active control: Wind turbine model

    DEFF Research Database (Denmark)

    Bindner, H.

    1999-01-01

    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...... 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...

  20. An Alternative Technique in the Control of Massive Presacral Rectal ...

    African Journals Online (AJOL)

    Bleeding control was provided by GORE‑TEX® graft. We conclude that fıxatıon of GORE‑TEX® aortic patch should be kept in mind for uncontrolled massive presacral bleeding. KEYWORDS: GORE‑TEX® graft, presacral bleeding, rectal cancer. An Alternative Technique in the Control of Massive Presacral Rectal. Bleeding: ...

  1. Active control: Wind turbine model

    Energy Technology Data Exchange (ETDEWEB)

    Bindner, Henrik

    1999-07-01

    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 design controllers. 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 has been done with extensive use of measurements as the basis for selection of model complexity and model 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. The models are all formulated as linear differential equations. The models are validated through comparisons with measurements performed on a Vestas WD 34 400 kW wind turbine. It is shown from a control point of view simple linear models can be used to describe the dynamic behavior of a pitch controlled wind turbine. The model and the measurements corresponds well in the relevant frequency range. The developed model is therefore applicable for controller design. (au) EFP-91. 18 ills., 22 refs.

  2. Effect of active learning techniques on students' choice of approach ...

    African Journals Online (AJOL)

    The purpose of this article is to report on empirical work, related to a techniques module, undertaken with the dental students of the University of the Western Cape, South Africa. I will relate how a range of different active learning techniques (tutorials; question papers and mock tests) assisted students to adopt a deep ...

  3. The application of different techniques to determine activated sludge ...

    African Journals Online (AJOL)

    The application of different techniques to determine activated sludge kinetic parameters in a food industry wastewater. ... method) and a respirometric technique based on oxygen consumption measurements, were used to compare microbial parameters using a wastewater model system of a potato processing plant.

  4. Thin layer activation techniques in research and industry

    International Nuclear Information System (INIS)

    Conlon, T.W.

    1993-01-01

    The following key application of thin layer activation technique (TLA) are discussed: ion-erosion in fusion tokamaks, bio-engineering technology, automobile industry. Future developments of the techniques, such as fission fragment TLA, multi-layer TLA and recoil implantation are discussed as well. 7 refs, 6 figs, 1 tab

  5. Controlling and tracking hyperchaotic Roessler system via active backstepping design

    International Nuclear Information System (INIS)

    Zhang Hao; Ma Xikui; Li Ming; Zou Jianlong

    2005-01-01

    This paper presents a novel active backstepping control approach for controlling hyperchaotic Roessler system to a steady state as well as tracking of any desire trajectory to be achieved in a systematic way. The proposed method is a systematic design approach and consists in a recursive procedure that interlaces the choice of a Lyapunov function with the design of active control. Numerical results show that the controller is singularity free and the closed-loop system is stable globally. Especially, the main feature of this technique is that it gives the flexibility to construct a control law. Finally, numerical experiments verify the feasibility and effectiveness of the proposed control technique

  6. Neutron activation analysis: an emerging technique for conservation/preservation

    International Nuclear Information System (INIS)

    Sayre, E.V.

    1976-01-01

    The diverse applications of neutron activation in analysis, preservation, and documentation of art works and artifacts are described with illustrations for each application. The uses of this technique to solve problems of attribution and authentication, to reveal the inner structure and composition of art objects, and, in some instances to recreate details of the objects are described. A brief discussion of the theory and techniques of neutron activation analysis is also included

  7. Engine control techniques to account for fuel effects

    Science.gov (United States)

    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.

  8. Evaluation of nuclear reactor based activation analysis techniques

    International Nuclear Information System (INIS)

    Obrusnik, I.; Kucera, J.

    1977-09-01

    A survey is presented of the basic types of activation analysis applied in environmental control. Reactor neutron activation analysis is described (including the reactor as a neutron source, sample activation in the reactor, methodology of neutron activation analysis, sample transport into the reactor and sample packaging after irradiation, instrumental activation analysis with radiochemical separation, data measurement and evaluation, sampling and sample preparation). Sources of environmental contamination with trace elements, sampling and sample analysis by neutron activation are described. The analysis is described of soils, waters and biological materials. Methods are shown of evaluating neutron activation analysis results and of their interpretation for purposes of environmental control. (J.B.)

  9. Coherent active polarization control without loss

    Science.gov (United States)

    Ye, Yuqian; Hay, Darrick; Shi, Zhimin

    2017-11-01

    We propose a lossless active polarization control mechanism utilizing an anisotropic dielectric medium with two coherent inputs. Using scattering matrix analysis, we derive analytically the required optical properties of the anisotropic medium that can behave as a switchable polarizing beam splitter. We also show that such a designed anisotropic medium can produce linearly polarized light at any azimuthal direction through coherent control of two inputs with a specific polarization state. Furthermore, we present a straightforward design-on-demand procedure of a subwavelength-thick metastructure that can possess the desired optical anisotropy at a flexible working wavelength. Our lossless coherent polarization control technique may lead to fast, broadband and integrated polarization control elements for applications in imaging, spectroscopy, and telecommunication.

  10. Coherent active polarization control without loss

    Directory of Open Access Journals (Sweden)

    Yuqian Ye

    2017-11-01

    Full Text Available We propose a lossless active polarization control mechanism utilizing an anisotropic dielectric medium with two coherent inputs. Using scattering matrix analysis, we derive analytically the required optical properties of the anisotropic medium that can behave as a switchable polarizing beam splitter. We also show that such a designed anisotropic medium can produce linearly polarized light at any azimuthal direction through coherent control of two inputs with a specific polarization state. Furthermore, we present a straightforward design-on-demand procedure of a subwavelength-thick metastructure that can possess the desired optical anisotropy at a flexible working wavelength. Our lossless coherent polarization control technique may lead to fast, broadband and integrated polarization control elements for applications in imaging, spectroscopy, and telecommunication.

  11. Object oriented programming techniques applied to device access and control

    International Nuclear Information System (INIS)

    Goetz, A.; Klotz, W.D.; Meyer, J.

    1992-01-01

    In this paper a model, called the device server model, has been presented for solving the problem of device access and control faced by all control systems. Object Oriented Programming techniques were used to achieve a powerful yet flexible solution. The model provides a solution to the problem which hides device dependancies. It defines a software framework which has to be respected by implementors of device classes - this is very useful for developing groupware. The decision to implement remote access in the root class means that device servers can be easily integrated in a distributed control system. A lot of the advantages and features of the device server model are due to the adoption of OOP techniques. The main conclusion that can be drawn from this paper is that 1. the device access and control problem is adapted to being solved with OOP techniques, 2. OOP techniques offer a distinct advantage over traditional programming techniques for solving the device access problem. (J.P.N.)

  12. 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.

  13. Optogenetic control of epileptiform activity

    DEFF Research Database (Denmark)

    Tønnesen, Jan; Sørensen, Andreas T; Deisseroth, Karl

    2009-01-01

    such an optogenetic approach using the light-driven halorhodopsin chloride pump from Natronomonas pharaonis (NpHR), modified for mammalian CNS expression to hyperpolarize central neurons, may inhibit excessive hyperexcitability and epileptiform activity. We show that a lentiviral vector containing the NpHR gene under...... that the optogenetic approach may prove useful for controlling epileptiform activity and opens a future perspective to develop it into a strategy to treat epilepsy.......The optogenetic approach to gain control over neuronal excitability both in vitro and in vivo has emerged as a fascinating scientific tool to explore neuronal networks, but it also opens possibilities for developing novel treatment strategies for neurologic conditions. We have explored whether...

  14. THE PHASE REACTOR INDUCTANCE SELECTION TECHNIQUE FOR POWER ACTIVE FILTER

    Directory of Open Access Journals (Sweden)

    D. V. Tugay

    2016-12-01

    Full Text Available Purpose. The goal is to develop technique of the phase inductance power reactors selection for parallel active filter based on the account both low-frequency and high-frequency components of the electromagnetic processes in a power circuit. Methodology. We have applied concepts of the electrical circuits theory, vector analysis, mathematical simulation in Matlab package. Results. We have developed a new technique of the phase reactors inductance selection for parallel power active filter. It allows us to obtain the smallest possible value of THD network current. Originality. We have increased accuracy of methods of the phase reactor inductance selection for power active filter. Practical value. The proposed technique can be used in the design and manufacture of the active power filter for real objects of energy supply.

  15. LFC based adaptive PID controller using ANN and ANFIS techniques

    Directory of Open Access Journals (Sweden)

    Mohamed I. Mosaad

    2014-12-01

    Full Text Available This paper presents an adaptive PID Load Frequency Control (LFC for power systems using Neuro-Fuzzy Inference Systems (ANFIS and Artificial Neural Networks (ANN oriented by Genetic Algorithm (GA. PID controller parameters are tuned off-line by using GA to minimize integral error square over a wide-range of load variations. The values of PID controller parameters obtained from GA are used to train both ANFIS and ANN. Therefore, the two proposed techniques could, online, tune the PID controller parameters for optimal response at any other load point within the operating range. Testing of the developed techniques shows that the adaptive PID-LFC could preserve optimal performance over the whole loading range. Results signify superiority of ANFIS over ANN in terms of performance measures.

  16. Research on activation analysis using short-lived isotopes and a multi-purpose isotopic neutron irradiator. Part of a coordinated programme on on-line X-ray and neutron techniques for industrial process control

    International Nuclear Information System (INIS)

    Ozek, F.

    1981-02-01

    A method of cyclic activation analysis (CA) has been studied and applied. A theoretical comparison between cyclic and conventional neutron activation analysis of gold has been made. The optimum number of cycles in cyclic activation have been investigated and an equation for the rapid calculation of the number of cycles is proposed. The isotopic neutron irradiation system including the 5Ci Pu-Be neutron source was designed and constructed. The system is flexible and transportable and is capable of carrying out prompt and conventional delay gamma-ray analysis and cyclic activation of bulk materials. The advantages as well as the disadvantages of neutron activation analysis with the use of short-lived nuclides were considered, and can be summarized as follows: Advantages: saturation factor approaches unity, speed of analysis, low cost of analysis, increased selectivity, reduced matrix activities. Disadvantages: proximity of neutron source, chemical separation hardly possible or impossible, total number of counts low. Low counting rates can be substantially increased by applying the technique of ''cyclic activation'', which is another reason by the use of short-lived isotopes in neutron activation analysis is steadily becoming more attractive

  17. The regeneration of polluted active carbon by radiation techniques

    International Nuclear Information System (INIS)

    Bao Borong; Wu Minghong; Hu Longxin; Zhou Riumin; Zhu Jinliang

    1998-01-01

    In this paper, we investigated the regeneration of polluted active carbon from monosodium glutamate factory by combination of radiation and acid-alkali chemical techniques. The experimental results show that the polluted active carbon will be highly regenerated on the conditions of process concentration 3%, process time 0.5 hour and the adjustment process concentration 2%, time 0.5 hour, radiation dose 5kGy. As regeneration times increase, the regenerated active carbon behaves with good repetition and stable property

  18. Development of irradiation technique on controlling food contamination residue

    International Nuclear Information System (INIS)

    Liu Bin; Xiong Shanbai; Xiong Guangquan; Cheng Wei; Chen Yuxia; Liao Tao; Li Xin; Lin Ruotai

    2010-01-01

    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)

  19. Sterile insect technique and radiation in insect control

    International Nuclear Information System (INIS)

    1982-01-01

    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

  20. 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.

  1. VAR control in distribution systems by using artificial intelligence techniques

    Energy Technology Data Exchange (ETDEWEB)

    Golkar, M.A. [Curtin Univ. of Technology, Sarawak (Malaysia). School of Engineering and Science

    2005-07-01

    This paper reviewed artificial intelligence techniques used in VAR control systems. Reactive power controls in distribution systems were also reviewed. While artificial intelligence methods are widely used in power control systems, the techniques require extensive human knowledge bases and experiences in order to operate correctly. Expert systems use knowledge and interface procedures to solve problems that often require human expertise. Expert systems often cause knowledge bottlenecks as they are unable to learn or adopt to new situations. While neural networks possess learning ability, they are computationally expensive. However, test results in recent neural network studies have demonstrated that they work well in a variety of loading conditions. Fuzzy logic techniques are used to accurately represent the operational constraints of power systems. Fuzzy logic has an advantage over other artificial intelligence techniques as it is able to remedy uncertainties in data. Evolutionary computing algorithms use probabilistic transition rules which can search complicated data to determine optimal constraints and parameters. Over 95 per cent of all papers published on power systems use genetic algorithms. It was concluded that hybrid systems using various artificial intelligence techniques are now being used by researchers. 69 refs.

  2. Greenhouse Environmental Control Using Optimized MIMO PID Technique

    Directory of Open Access Journals (Sweden)

    Fateh BOUNAAMA

    2011-10-01

    Full Text Available Climate control for protected crops brings the added dimension of a biological system into a physical system control situation. The thermally dynamic nature of a greenhouse suggests that disturbance attenuation (load control of external temperature, humidity, and sunlight is far more important than is the case for controlling other types of buildings. This paper investigates the application of multi-inputs multi-outputs (MIMO PID controller to a MIMO greenhouse environmental model with actuation constraints. This method is based on decoupling the system at low frequency point. The optimal tuning values are determined using genetic algorithms optimization (GA. The inside outsides climate model of the environmental greenhouse, and the automatically collected data sets of Avignon, France are used to simulate and test this technique. The control objective is to maintain a highly coupled inside air temperature and relative humidity of strongly perturbed greenhouse, at specified set-points, by the ventilation/cooling and moisturizing operations.

  3. Advanced analytical techniques for boiling water reactor chemistry control

    Energy Technology Data Exchange (ETDEWEB)

    Alder, H P; Schenker, E [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-02-01

    The analytical techniques applied can be divided into 5 classes: OFF-LINE (discontinuous, central lab), AT-LINE (discontinuous, analysis near loop), ON-LINE (continuous, analysis in bypass). In all cases pressure and temperature of the water sample are reduced. In a strict sense only IN-LINE (continuous, flow disturbance) and NON-INVASIVE (continuous, no flow disturbance) techniques are suitable for direct process control; - the ultimate goal. An overview of the analytical techniques tested in the pilot loop is given. Apart from process and overall water quality control, standard for BWR operation, the main emphasis is on water impurity characterization (crud particles, hot filtration, organic carbon); on stress corrosion crackling control for materials (corrosion potential, oxygen concentration) and on the characterization of the oxide layer on austenites (impedance spectroscopy, IR-reflection). The above mentioned examples of advanced analytical techniques have the potential of in-line or non-invasive application. They are different stages of development and are described in more detail. 28 refs, 1 fig., 5 tabs.

  4. Insect population control by the sterile-male technique

    Energy Technology Data Exchange (ETDEWEB)

    Lindquist, A W

    1963-10-01

    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.

  5. Insect population control by the sterile-male technique

    International Nuclear Information System (INIS)

    Lindquist, A.W.

    1963-01-01

    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

  6. 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.

  7. Positron Plasma Control Techniques Applied to Studies of Cold Antihydrogen

    CERN Document Server

    Funakoshi, Ryo

    2003-01-01

    In the year 2002, two experiments at CERN succeeded in producing cold antihydrogen atoms, first ATHENA and subsequently ATRAP. Following on these results, it is now feasible to use antihydrogen to study the properties of antimatter. In the ATHENA experiment, the cold antihydrogen atoms are produced by mixing large amounts of antiprotons and positrons in a nested Penning trap. The complicated behaviors of the charged particles are controlled and monitored by plasma manipulation techniques. The antihydrogen events are studied using position sensitive detectors and the evidence of production of antihydrogen atoms is separated out with the help of analysis software. This thesis covers the first production of cold antihydrogen in the first section as well as the further studies of cold antihydrogen performed by using the plasma control techniques in the second section.

  8. Statistic techniques of process control for MTR type

    International Nuclear Information System (INIS)

    Oliveira, F.S.; Ferrufino, F.B.J.; Santos, G.R.T.; Lima, R.M.

    2002-01-01

    This work aims at introducing some improvements on the fabrication of MTR type fuel plates, applying statistic techniques of process control. The work was divided into four single steps and their data were analyzed for: fabrication of U 3 O 8 fuel plates; fabrication of U 3 Si 2 fuel plates; rolling of small lots of fuel plates; applying statistic tools and standard specifications to perform a comparative study of these processes. (author)

  9. 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.

  10. Burn Control in Fusion Reactors via Nonlinear Stabilization Techniques

    International Nuclear Information System (INIS)

    Schuster, Eugenio; Krstic, Miroslav; Tynan, George

    2003-01-01

    Control of plasma density and temperature magnitudes, as well as their profiles, are among the most fundamental problems in fusion reactors. Existing efforts on model-based control use control techniques for linear models. In this work, a zero-dimensional nonlinear model involving approximate conservation equations for the energy and the densities of the species was used to synthesize a nonlinear feedback controller for stabilizing the burn condition of a fusion reactor. The subignition case, where the modulation of auxiliary power and fueling rate are considered as control forces, and the ignition case, where the controlled injection of impurities is considered as an additional actuator, are treated separately.The model addresses the issue of the lag due to the finite time for the fresh fuel to diffuse into the plasma center. In this way we make our control system independent of the fueling system and the reactor can be fed either by pellet injection or by puffing. This imposed lag is treated using nonlinear backstepping.The nonlinear controller proposed guarantees a much larger region of attraction than the previous linear controllers. In addition, it is capable of rejecting perturbations in initial conditions leading to both thermal excursion and quenching, and its effectiveness does not depend on whether the operating point is an ignition or a subignition point.The controller designed ensures setpoint regulation for the energy and plasma parameter β with robustness against uncertainties in the confinement times for different species. Hence, the controller can increase or decrease β, modify the power, the temperature or the density, and go from a subignition to an ignition point and vice versa

  11. Practical applications of activation analysis and other nuclear techniques

    International Nuclear Information System (INIS)

    Lyon, W.S.

    1982-01-01

    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

  12. An investigation of tungsten by neutron activation techniques

    International Nuclear Information System (INIS)

    Svetsreni, R.

    1978-01-01

    This investigation used neutron from Plutonium-Beryllium source (5 curie) to analyse the amount of tungsten in tungsten oxide which was extracted from tungsten ores, slag and tungsten alloy of tungsten iron and carbon. The technique of neutron activation analysis with NaI(Tl) gamma detector 3'' x 3'' and 1024 multichannel analyzer. The dilution technique was used by mixing Fe 2 O 3 or pure sand into the sample before irradiation. In this study self shielding effect in the analysis of tungsten was solved and the detection limit of the tungsten in the sample was about 0.5%

  13. Control technique for enhancing the stable operation of distributed generation units within a microgrid

    International Nuclear Information System (INIS)

    Mehrasa, Majid; Pouresmaeil, Edris; Mehrjerdi, Hasan; Jørgensen, Bo Nørregaard; Catalão, João P.S.

    2015-01-01

    Highlights: • A control technique for enhancing the stable operation of distributed generation units is proposed. • Passivity-based control technique is considered to analyze the dynamic and steady-state behaviors. • The compensation of instantaneous variations in the reference current components is considered. • Simulation results confirm the performance of the control scheme within the microgrid. - Abstract: This paper describes a control technique for enhancing the stable operation of distributed generation (DG) units based on renewable energy sources, during islanding and grid-connected modes. The Passivity-based control technique is considered to analyze the dynamic and steady-state behaviors of DG units during integration and power sharing with loads and/or power grid, which is an appropriate tool to analyze and define a stable operating condition for DG units in microgrid technology. The compensation of instantaneous variations in the reference current components of DG units in ac-side, and dc-link voltage variations in dc-side of interfaced converters, are considered properly in the control loop of DG units, which is the main contribution and novelty of this control technique over other control strategies. By using the proposed control technique, DG units can provide the continuous injection of active power from DG sources to the local loads and/or utility grid. Moreover, by setting appropriate reference current components in the control loop of DG units, reactive power and harmonic current components of loads can be supplied during the islanding and grid-connected modes with a fast dynamic response. Simulation results confirm the performance of the control scheme within the microgrid during dynamic and steady-state operating conditions

  14. 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

  15. Quality assurance and quality control of nuclear analytical techniques

    International Nuclear Information System (INIS)

    Cincu, Emanuelathor

    2001-01-01

    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

  16. 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...

  17. Root activity evaluation in tree crops using isotopic techniques

    International Nuclear Information System (INIS)

    Calvache, Marcelo

    1991-01-01

    This paper discusses the methdology used to evalute root activity of the crops utilizing the technique of soil injection with solutions marked with isotopes. Some of the experimental data obtained with coffee, citrus and oil palm are also presented. Ovel all, these tree crops present a higher root activity in soil layers close to the surface (0-20 cm) and to a distance from the trunk which varies with age, season and variety. The most important conclusions are: 1. The isotope injection technique using 3 2 P , 1 5 N , or 8 5 R b, allow direct and reliable determination of root activity in these tree crops. 2. Root activity of three crops depends on age of the tree, variety, moisture content of the soil and soil type. 3. Soil moisture is the most influencial factor affecting root activity. This is turn depends on the irrigation method employed. 4. From the practical view point, the best distance from the trunk to apply fertilizer in the one wich has highest root activity closest to the soil surface

  18. Run control techniques for the Fermilab DART data acquisition system

    International Nuclear Information System (INIS)

    Oleynik, G.; Engelfried, J.; Mengel, L.; Moore, C.; Pordes, R.; Udumula, L.; Votava, M.; Drunen, E. van; Zioulas, G.

    1996-01-01

    DART is the high speed, Unix based data acquisition system being developed by the Fermilab Computing Division in collaboration with eight High Energy Physics Experiments. This paper describes DART run-control which implements flexible, distributed, extensible and portable paradigms for the control monitoring of a data acquisition systems. We discuss the unique and interesting aspects of the run-control - why we chose the concepts we did, the benefits we have seen from the choices we made, as well as our experiences in deploying and supporting it for experiments during their commissioning and sub-system testing phases. We emphasize the software and techniques we believe are extensible to future use, and potential future modifications and extensions for those we feel are not. (author)

  19. L2-gain and passivity techniques in nonlinear control

    CERN Document Server

    van der Schaft, Arjan

    2017-01-01

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

  20. Run control techniques for the Fermilab DART data acquisition system

    International Nuclear Information System (INIS)

    Oleynik, G.; Engelfried, J.; Mengel, L.

    1995-10-01

    DART is the high speed, Unix based data acquisition system being developed by the Fermilab Computing Division in collaboration with eight High Energy Physics Experiments. This paper describes DART run-control which implements flexible, distributed, extensible and portable paradigms for the control and monitoring of data acquisition systems. We discuss the unique and interesting aspects of the run-control - why we chose the concepts we did, the benefits we have seen from the choices we made, as well as our experiences in deploying and supporting it for experiments during their commissioning and sub-system testing phases. We emphasize the software and techniques we believe are extensible to future use, and potential future modifications and extensions for those we feel are not

  1. Comparison of backstepping and modified active control in ...

    Indian Academy of Sciences (India)

    In this article, projective synchronization of double–scroll attractor of an extended Bonöffer–van der Pol oscillator (BVPO) is considered via the backstepping and active control techniques. In each synchronization scheme, a single control function is designed to achieve projective synchronization between two Bonhöffer–van ...

  2. Control System Design for Cylindrical Tank Process Using Neural Model Predictive Control Technique

    Directory of Open Access Journals (Sweden)

    M. Sridevi

    2010-10-01

    Full Text Available Chemical manufacturing and process industry requires innovative technologies for process identification. This paper deals with model identification and control of cylindrical process. Model identification of the process was done using ARMAX technique. A neural model predictive controller was designed for the identified model. The performance of the controllers was evaluated using MATLAB software. The performance of NMPC controller was compared with Smith Predictor controller and IMC controller based on rise time, settling time, overshoot and ISE and it was found that the NMPC controller is better suited for this process.

  3. 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.

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

    International Nuclear Information System (INIS)

    Kehler, P.

    1978-01-01

    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 percent, and average densities were measured down to 0.08 g/cm 3 with an accuracy of 0.04 g/cm 3 . 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/cm 3 for 12.5 cm pipes, and to even lower ranges for larger pipes

  5. Some problems of calibration technique in charged particle activation analysis

    International Nuclear Information System (INIS)

    Krasnov, N.N.; Zatolokin, B.V.; Konstantinov, I.O.

    1977-01-01

    It is shown that three different approaches to calibration technique based on the use of average cross-section, equivalent target thickness and thick target yield are adequate. Using the concept of thick target yield, a convenient charged particle activation equation is obtained. The possibility of simultaneous determination of two impurities, from which the same isotope is formed, is pointed out. The use of the concept of thick target yield facilitates the derivation of a simple formula for an absolute and comparative methods of analysis. The methodical error does not exceed 10%. Calibration technique and determination of expected sensitivity based on the thick target yield concept is also very convenient because experimental determination of thick target yield values is a much simpler procedure than getting activation curve or excitation function. (T.G.)

  6. 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.

  7. Fusion alpha loss diagnostic for ITER using activation technique

    Czech Academy of Sciences Publication Activity Database

    Bonheure, G.; Hult, M.; González de Orduña, R.; Vermaercke, P.; Murari, A.; Popovichev, S.; Mlynář, Jan

    2011-01-01

    Roč. 86, 6-8 (2011), s. 1298-1301 ISSN 0920-3796. [Symposium on Fusion Technology (SOFT) /26th./. Port o, 27.09.2010-01.10.2010] Institutional research plan: CEZ:AV0Z20430508 Keywords : ITER * fusion product * burning plasma diagnostics * alpha losses * activation technique Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.490, year: 2011 http://www.sciencedirect.com/science/article/pii/S0920379611002778

  8. 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

  9. Alar setback technique: a controlled method of nasal tip deprojection.

    Science.gov (United States)

    Foda, H M

    2001-11-01

    To describe an alar cartilage-modifying technique aimed at decreasing nasal tip projection in cases with overdeveloped alar cartilages and to compare it with other deprojection techniques used to correct such deformity. Selected case series. University and private practice settings in Alexandria, Egypt. Twenty patients presenting for rhinoplasty who had overprojected nasal tips primarily due to overdeveloped alar cartilages. All cases were primary cases except for one patient, who had undergone 2 previous rhinoplasties. An external rhinoplasty approach was used to set back the alar cartilages by shortening their medial and lateral crura. The choice of performing a high or low setback depended on the preexisting lobule-to-columella ratio. Following the setback, the alar cartilages were reconstructed in a fashion that increased the strength and stability of the tip complex. Subjective evaluation included clinical examination, analysis of preoperative and postoperative photographs, and patient satisfaction. Objective evaluation of nasal tip projection, using the Goode ratio and the nasofacial angle, was performed preoperatively and repeated at least 6 months postoperatively. A low setback was performed in 16 cases (80%) and a high setback in 4 (20%). The mean follow-up period was 18 months (range, 6-36 months). The technique effectively deprojected the nasal tip as evidenced by the considerable postoperative decrease in values of the Goode ratio and the nasofacial angle. No complications were encountered and no revision surgical procedures were required. The alar setback technique has many advantages; it results in precise predictable amounts of deprojection, controls the degree of tip rotation, preserves the natural contour of the nasal tip, respects the tip support mechanisms, increases the strength and stability of nasal tip complex, preserves or restores the normal lobule-to-columella proportion, and does not lead to alar flaring. However, the technique requires

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

    International Nuclear Information System (INIS)

    1991-07-01

    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

  11. 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.

  12. Active Vibration damping of Smart composite beams based on system identification technique

    Science.gov (United States)

    Bendine, Kouider; Satla, Zouaoui; Boukhoulda, Farouk Benallel; Nouari, Mohammed

    2018-03-01

    In the present paper, the active vibration control of a composite beam using piezoelectric actuator is investigated. The space state equation is determined using system identification technique based on the structure input output response provided by ANSYS APDL finite element package. The Linear Quadratic (LQG) control law is designed and integrated into ANSYS APDL to perform closed loop simulations. Numerical examples for different types of excitation loads are presented to test the efficiency and the accuracy of the proposed model.

  13. DC Microgrids–Part I: A Review of Control Strategies and Stabilization Techniques

    Energy Technology Data Exchange (ETDEWEB)

    Dragicevic, Tomislav; Lu, Xiaonan; Vasquez, Juan; Guerrero, Josep

    2015-01-01

    This paper presents a review of control strategies, stability analysis, and stabilization techniques for dc microgrids (MGs). Overall control is systematically classified into local and coordinated control levels according to respective functionalities in each level. As opposed to local control, which relies only on local measurements, some line of communication between units needs to be made available in order to achieve the coordinated control. Depending on the communication method, three basic coordinated control strategies can be distinguished, i.e., decentralized, centralized, and distributed control. Decentralized control can be regarded as an extension of the local control since it is also based exclusively on local measurements. In contrast, centralized and distributed control strategies rely on digital communication technologies. A number of approaches using these three coordinated control strategies to achieve various control objectives are reviewed in this paper. Moreover, properties of dc MG dynamics and stability are discussed. This paper illustrates that tightly regulated point-of-load converters tend to reduce the stability margins of the system since they introduce negative impedances, which can potentially oscillate with lightly damped power supply input filters. It is also demonstrated that how the stability of the whole system is defined by the relationship of the source and load impedances, referred to as the minor loop gain. Several prominent specifications for the minor loop gain are reviewed. Finally, a number of active stabilization techniques are presented.

  14. Spectroscopic analysis technique for arc-welding process control

    Science.gov (United States)

    Mirapeix, Jesús; Cobo, Adolfo; Conde, Olga; Quintela, María Ángeles; López-Higuera, José-Miguel

    2005-09-01

    The spectroscopic analysis of the light emitted by thermal plasmas has found many applications, from chemical analysis to monitoring and control of industrial processes. Particularly, it has been demonstrated that the analysis of the thermal plasma generated during arc or laser welding can supply information about the process and, thus, about the quality of the weld. In some critical applications (e.g. the aerospace sector), an early, real-time detection of defects in the weld seam (oxidation, porosity, lack of penetration, ...) is highly desirable as it can reduce expensive non-destructive testing (NDT). Among others techniques, full spectroscopic analysis of the plasma emission is known to offer rich information about the process itself, but it is also very demanding in terms of real-time implementations. In this paper, we proposed a technique for the analysis of the plasma emission spectrum that is able to detect, in real-time, changes in the process parameters that could lead to the formation of defects in the weld seam. It is based on the estimation of the electronic temperature of the plasma through the analysis of the emission peaks from multiple atomic species. Unlike traditional techniques, which usually involve peak fitting to Voigt functions using the Levenberg-Marquardt recursive method, we employ the LPO (Linear Phase Operator) sub-pixel algorithm to accurately estimate the central wavelength of the peaks (allowing an automatic identification of each atomic species) and cubic-spline interpolation of the noisy data to obtain the intensity and width of the peaks. Experimental tests on TIG-welding using fiber-optic capture of light and a low-cost CCD-based spectrometer, show that some typical defects can be easily detected and identified with this technique, whose typical processing time for multiple peak analysis is less than 20msec. running in a conventional PC.

  15. Trends in microbial control techniques for poultry products.

    Science.gov (United States)

    Silva, Filomena; Domingues, Fernanda C; Nerín, Cristina

    2018-03-04

    Fresh poultry meat and poultry products are highly perishable foods and high potential sources of human infection due to the presence of several foodborne pathogens. Focusing on the microbial control of poultry products, the food industry generally implements numerous preventive measures based on the Hazard Analysis and Critical Control Points (HACCP) food safety management system certification together with technological steps, such as refrigeration coupled to modified atmosphere packaging that are able to control identified potential microbial hazards during food processing. However, in recent years, to meet the demand of consumers for minimally processed, high-quality, and additive-free foods, technologies are emerging associated with nonthermal microbial inactivation, such as high hydrostatic pressure, irradiation, and natural alternatives, such as biopreservation or the incorporation of natural preservatives in packaging materials. These technologies are discussed throughout this article, emphasizing their pros and cons regarding the control of poultry microbiota and their effects on poultry sensory properties. The discussion for each of the preservation techniques mentioned will be provided with as much detail as the data and studies provided in the literature for poultry meat and products allow. These new approaches, on their own, have proved to be effective against a wide range of microorganisms in poultry meat. However, since some of these emergent technologies still do not have full consumer's acceptability and, taking into consideration the hurdle technology concept for poultry processing, it is suggested that they will be used as combined treatments or, more frequently, in combination with modified atmosphere packaging.

  16. Effect of novel inhaler technique reminder labels on the retention of inhaler technique skills in asthma: a single-blind randomized controlled trial.

    Science.gov (United States)

    Basheti, Iman A; Obeidat, Nathir M; Reddel, Helen K

    2017-02-09

    Inhaler technique can be corrected with training, but skills drop off quickly without repeated training. The aim of our study was to explore the effect of novel inhaler technique labels on the retention of correct inhaler technique. In this single-blind randomized parallel-group active-controlled study, clinical pharmacists enrolled asthma patients using controller medication by Accuhaler [Diskus] or Turbuhaler. Inhaler technique was assessed using published checklists (score 0-9). Symptom control was assessed by asthma control test. Patients were randomized into active (ACCa; THa) and control (ACCc; THc) groups. All patients received a "Show-and-Tell" inhaler technique counseling service. Active patients also received inhaler labels highlighting their initial errors. Baseline data were available for 95 patients, 68% females, mean age 44.9 (SD 15.2) years. Mean inhaler scores were ACCa:5.3 ± 1.0; THa:4.7 ± 0.9, ACCc:5.5 ± 1.1; THc:4.2 ± 1.0. Asthma was poorly controlled (mean ACT scores ACCa:13.9 ± 4.3; THa:12.1 ± 3.9; ACCc:12.7 ± 3.3; THc:14.3 ± 3.7). After training, all patients had correct technique (score 9/9). After 3 months, there was significantly less decline in inhaler technique scores for active than control groups (mean difference: Accuhaler -1.04 (95% confidence interval -1.92, -0.16, P = 0.022); Turbuhaler -1.61 (-2.63, -0.59, P = 0.003). Symptom control improved significantly, with no significant difference between active and control patients, but active patients used less reliever medication (active 2.19 (SD 1.78) vs. control 3.42 (1.83) puffs/day, P = 0.002). After inhaler training, novel inhaler technique labels improve retention of correct inhaler technique skills with dry powder inhalers. Inhaler technique labels represent a simple, scalable intervention that has the potential to extend the benefit of inhaler training on asthma outcomes. REMINDER LABELS IMPROVE INHALER TECHNIQUE: Personalized

  17. Development of active neutron interrogation techniques at Harwell

    International Nuclear Information System (INIS)

    Armitage, B.H.; Chard, P.M.J.; Packer, T.W.; Swinhoe, M.T.; Syme, D.B.

    1990-01-01

    Active neutron interrogation techniques capable of measuring the fissile content of a range of waste drum sizes and contents have been developed at Harwell. This paper describes measurements which have been made to investigate the behaviour of these assay systems for the difficult case of concreted waste in a heterogeneous matrix. The drums have been measured using a Cf shuffler and a differential die-away system, with supporting information obtained from a segmented gamma-scanner. Good correspondence has been observed between the two different neutron interrogation techniques. It was concluded that the measurement of highly heterogeneous wastes is likely to be more effective if calibration can be undertaken with representative artificial matrices. Further measurement and analysis remains to be undertaken

  18. Microencapsulation: A promising technique for controlled drug delivery.

    Science.gov (United States)

    Singh, M N; Hemant, K S Y; Ram, M; Shivakumar, H G

    2010-07-01

    MICROPARTICLES OFFER VARIOUS SIGNIFICANT ADVANTAGES AS DRUG DELIVERY SYSTEMS, INCLUDING: (i) an effective protection of the encapsulated active agent against (e.g. enzymatic) degradation, (ii) the possibility to accurately control the release rate of the incorporated drug over periods of hours to months, (iii) an easy administration (compared to alternative parenteral controlled release dosage forms, such as macro-sized implants), and (iv) Desired, pre-programmed drug release profiles can be provided which match the therapeutic needs of the patient. This article gives an overview on the general aspects and recent advances in drug-loaded microparticles to improve the efficiency of various medical treatments. An appropriately designed controlled release drug delivery system can be a foot ahead towards solving problems concerning to the targeting of drug to a specific organ or tissue, and controlling the rate of drug delivery to the target site. The development of oral controlled release systems has been a challenge to formulation scientist due to their inability to restrain and localize the system at targeted areas of gastrointestinal tract. Microparticulate drug delivery systems are an interesting and promising option when developing an oral controlled release system. The objective of this paper is to take a closer look at microparticles as drug delivery devices for increasing efficiency of drug delivery, improving the release profile and drug targeting. In order to appreciate the application possibilities of microcapsules in drug delivery, some fundamental aspects are briefly reviewed.

  19. Integration of advanced feedback control techniques on Tore Supra

    International Nuclear Information System (INIS)

    Barana, O.; Basiuk, V.; Bucalossi, J.

    2006-01-01

    Tore Supra tokamak plays an important role in development and optimisation of steady-state scenarios. Its real-time feedback control system is a key instrument to improve plasma performances. For this reason, new feedback control schemes have been recently put into operation and others are being developed. This work deals with the implementation in Tore Supra of these advanced algorithms, reports the technical details and shows the first positive results that have been achieved. For instance, encouraging results have been obtained in the field of profiles control. Controls of the full width at half maximum of the suprathermal electrons local emission profile at very low loop voltage and of the maximum of the thermal Larmor radius, normalised to the characteristic length of the electron temperature gradient, have been attained. While the first quantity can be directly associated to the current profile, the second one characterises the pressure profile. A new feedback control algorithm, employed to maximise a given quantity by means of a '' Search Optimisation '' technique, has been effectively tested too: the hard X-ray width has been maximised with simultaneous use of lower hybrid heating power and wave parallel index as actuators. These and other promising results, whose detailed description will be given in the article, have been obtained thanks to the real-time availability of several diagnostic systems. Using a shared memory network as communication layer, they send their measurements to a central computing unit that, in its turn, dispatches the necessary requirements to the actuators. A key issue is the possibility to integrate these controls in such a way as to cope with different requests at the same time. As an example, simultaneous control of the plasma current by means of the lower hybrid heating power, of the loop voltage by means of the poloidal field system and of the hard X-ray width through the lower hybrid heating phase shift has been successfully

  20. Robust satellite techniques for remote sensing of seismically active areas

    Energy Technology Data Exchange (ETDEWEB)

    Tramutoli, V; Di Bello, G [Potenza Univ., Potenza (Italy). Dipt. di Ingegneria e Fisica dell' Ambiente; Pergola, N; Piscitelli, S [Consiglio Nazionale delle Ricerche, Istituto di Metodologie Avanzate di Analisi Ambientale, Potenza (Italy)

    2001-04-01

    Several satellite techniques have been recently proposed to remotely map seismically active zones and to monitor geophysical phenomena possibly associated with earthquakes. Even if questionable in terms of their effective applicability, all these techniques highlight as the major problem, still to be overcome, the high number of natural factors (independent of any seismic activity) whose variable contributions to the investigated signal can be so high as to completely mask (or simulate) the space-time anomaly possibly associated to the seismic event under study. A robust approach (RAT) has recently been proposed (and successfully applied in the field of the monitoring of the major environmental risks) which, better than other methods, seems suitable for recognising space-time anomalies in the satellite observation field also in the presence of highly variable contributions from atmospheric (transmittance), surface (emissivity and morphology) and observational (time/season, but also solar and satellite zenithal angles) conditions. This work presents the first preliminary results, based on several years of NOA A/AVHRR observations, regarding its extension to satellite monitoring of thermal anomalies possibly associated to seismically active areas of Southern Italy. The main merits of this approach are its robustness against the possibility of false events detection (specially important for this kind of applications) as well as its intrinsic exportability not only to different geographic areas but also to different satellite instrumental packages.

  1. Robust satellite techniques for remote sensing of seismically active areas

    Directory of Open Access Journals (Sweden)

    S. Piscitelli

    2001-06-01

    Full Text Available Several satellite techniques have been recently proposed to remotely map seismically active zones and to monitor geophysical phenomena possibly associated with earthquakes. Even if questionable in terms of their effective applicability, all these techniques highlight as the major problem, still to be overcome, the high number of natural factors (independent of any seismic activity whose variable contributions to the investigated signal can be so high as to completely mask (or simulate the space-time anomaly possibly associated to the seismic event under study. A robust approach (RAT has recently been proposed (and successfully applied in the field of the monitoring of the major environmental risks which, better than other methods, seems suitable for recognising space-time anomalies in the satellite observational field also in the presence of highly variable contributions from atmospheric (transmittance, surface (emissivity and morphology and observational (time/season, but also solar and satellite zenithal angles conditions.This work presents the first preliminary results, based on several years of NOAA/AVHRR observations, regarding its extension to satellite monitoring of thermal anomalies possibly associated to seismically active areas of Southern Italy. The main merits of this approach are its robustness against the possibility of false events detection (specially important for this kind of applications as well as its intrinsic exportability not only to different geographic areas but also to different satellite instrumental packages.

  2. Robust intelligent backstepping tracking control for uncertain non-linear chaotic systems using H∞ control technique

    International Nuclear Information System (INIS)

    Peng, Y.-F.

    2009-01-01

    The cerebellar model articulation controller (CMAC) is a non-linear adaptive system with built-in simple computation, good generalization capability and fast learning property. In this paper, a robust intelligent backstepping tracking control (RIBTC) system combined with adaptive CMAC and H ∞ control technique is proposed for a class of chaotic systems with unknown system dynamics and external disturbance. In the proposed control system, an adaptive backstepping cerebellar model articulation controller (ABCMAC) is used to mimic an ideal backstepping control (IBC), and a robust H ∞ controller is designed to attenuate the effect of the residual approximation errors and external disturbances with desired attenuation level. Moreover, the all adaptation laws of the RIBTC system are derived based on the Lyapunov stability analysis, the Taylor linearization technique and H ∞ control theory, so that the stability of the closed-loop system and H ∞ tracking performance can be guaranteed. Finally, three application examples, including a Duffing-Holmes chaotic system, a Genesio chaotic system and a Sprott circuit system, are used to demonstrate the effectiveness and performance of proposed robust control technique.

  3. 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.

  4. Fetal response to abbreviated relaxation techniques. A randomized controlled study.

    Science.gov (United States)

    Fink, Nadine S; Urech, Corinne; Isabel, Fornaro; Meyer, Andrea; Hoesli, Irène; Bitzer, Johannes; Alder, Judith

    2011-02-01

    stress during pregnancy can have adverse effects on the course of pregnancy and on fetal development. There are few studies investigating the outcome of stress reduction interventions on maternal well-being and obstetric outcome. this study aims (1) to obtain fetal behavioral states (quiet/active sleep, quiet/active wakefulness), (2) to investigate the effects of maternal relaxation on fetal behavior as well as on uterine activity, and (3) to investigate maternal physiological and endocrine parameters as potential underlying mechanisms for maternal-fetal relaxation-transferral. the behavior of 33 fetuses was analyzed during laboratory relaxation/quiet rest (control group, CG) and controlled for baseline fetal behavior. Potential associations between relaxation/quiet rest and fetal behavior (fetal heart rate (FHR), FHR variation, FHR acceleration, and body movements) and uterine activity were studied, using a computerized cardiotocogram (CTG) system. Maternal heart rate, blood pressure, cortisol, and norepinephrine were measured. intervention (progressive muscle relaxation, PMR, and guided imagery, GI) showed changes in fetal behavior. The intervention groups had higher long-term variation during and after relaxation compared to the CG (p=.039). CG fetuses had more FHR acceleration, especially during and after quiet rest (p=.027). Women in the PMR group had significantly more uterine activity than women in the GI group (p=.011) and than CG women. Maternal heart rate, blood pressure, and stress hormones were not associated with fetal behavior. this study indicates that the fetus might participate in maternal relaxation and suggests that GI is superior to PMR. This could especially be true for women who tend to direct their attention to body sensations such as abdominal activity. 2010 Elsevier Ltd. All rights reserved.

  5. Active control versus recursive backstepping control of a chaotic ...

    African Journals Online (AJOL)

    In this paper active controllers and recursive backstepping controllers are designed for a third order chaotic system. The performances of these controllers in the control of the dynamics of the chaotic system are investigated numerically and are found to be effective. Comparison of their transient performances show that the ...

  6. The application of radiotracer technique for preconcentration neutron activation analysis

    International Nuclear Information System (INIS)

    Wang Xiaolin; Chen Yinliang; Sun Ying; Fu Yibei

    1995-01-01

    The application of radiotracer technique for preconcentration neutron activation analysis (Pre-NAA) are studied and the method for determination of chemical yield of Pre-NAA is developed. This method has been applied to determination of gold, iridium and rhenium in steel and rock samples and the contents of noble metal are in the range of 1-20 ng·g -1 (sample). In addition, the accuracy difference caused by determination of chemical yield between RNAA and Pre-NAA are also discussed

  7. Pulsed neutron generator for use with pulsed neutron activation techniques

    International Nuclear Information System (INIS)

    Rochau, G.E.

    1980-01-01

    A high-output, transportable, pulsed neutron generator has been developed by Sandia National Laboratories for use with Pulsed Neutron Activation (PNA) techniques. The PNA neutron generator generates > 10 10 14 MeV D-T neutrons in a 1.2 millisecond pulse. Each operation of the unit will produce a nominal total neutron output of 1.2 x 10 10 neutrons. The generator has been designed to be easily repaired and modified. The unit requires no additional equipment for operation or measurement of output

  8. Using geophysical techniques to control in situ thermal remediation

    International Nuclear Information System (INIS)

    Boyd, S.; Daily, W.; Ramirez, A.; Wilt, M.; Goldman, R.; Kayes, D.; Kenneally, K.; Udell, K.; Hunter, R.

    1994-01-01

    Monitoring the thermal and hydrologic processes that occur during thermal environmental remediation programs in near real-time provides essential information for controlling the process. Geophysical techniques played a crucial role in process control as well as for characterization during the recent Dynamic Underground Stripping Project demonstration in which several thousand gallons of gasoline were removed from heterogeneous soils both above and below the water table. Dynamic Underground Stripping combines steam injection and electrical heating for thermal enhancement with ground water pumping and vacuum extraction for contaminant removal. These processes produce rapid changes in the subsurface properties including changes in temperature fluid saturation, pressure and chemistry. Subsurface imaging methods are used to map the heated zones and control the thermal process. Temperature measurements made in wells throughout the field reveal details of the complex heating phenomena. Electrical resistance tomography (ERT) provides near real-time detailed images of the heated zones between boreholes both during electrical heating and steam injection. Borehole induction logs show close correlation with lithostratigraphy and, by identifying the more permeable gravel zones, can be used to predict steam movement. They are also useful in understanding the physical changes in the field and in interpreting the ERT images. Tiltmeters provide additional information regarding the shape of the steamed zones in plan view. They were used to track the growth of the steam front from individual injectors

  9. Characterizing root activity of guava trees by radiotracer technique

    International Nuclear Information System (INIS)

    Purohit, A.G.; Mukherjee, S.K.

    1974-01-01

    The distribution pattern of root activity of 12-year-old trees of guava (Psidium guajava L.) was determined by radiotracer technique. 32 P soloution was injected into the soil at lateral distances of 120, 240 and 360 cm from the tree trunk at depths of 15,30,60 and 90 cm. The 32 P uptake by the tree was determined by leaf analysis. In the rainy season the root activity or 32 P uptake was greater near the soil surface and midway between the trunk and the drip-line. The root activity decreased with an increase in the depth and distance from trunk. These results compared well with the actual distribution of feeder roots as determined by the soil-auger method. In summer the roots near the surface become less active in 32 P absorption with a drcrease in surface soil moisture. A decrease in the root activity in the surface soil was accompanied by an increase in 32 P uptake from lower depths. (author)

  10. 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,…

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

    Energy Technology Data Exchange (ETDEWEB)

    EI-Motaium, R A [Plant Research Department, Nuclear Research Ceter, Atomic Energy Authority, Inshas P.O. Box 13759, Cairo (Egypt)

    2007-07-01

    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 ( {sup 60}Co) 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 {sup 15}N-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 {sup 32}p 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

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

    International Nuclear Information System (INIS)

    EI-Motaium, R.A.

    2007-01-01

    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 ( 60 Co) 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 15 N-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 32 p 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

  13. Detection of uranium enrichment activities using environmental monitoring techniques

    International Nuclear Information System (INIS)

    Belew, W.L.; Carter, J.A.; Smith, D.H.; Walker, R.L.

    1993-01-01

    Uranium enrichment processes have the capability of producing weapons-grade material in the form of highly enriched uranium. Thus, detection of undeclared uranium enrichment activities is an international safeguards concern. The uranium separation technologies currently in use employ UF 6 gas as a separation medium, and trace quantities of enriched uranium are inevitably released to the environment from these facilities. The isotopic content of uranium in the vegetation, soil, and water near the plant site will be altered by these releases and can provide a signature for detecting the presence of enriched uranium activities. This paper discusses environmental sampling and analytical procedures that have been used for the detection of uranium enrichment facilities and possible safeguards applications of these techniques

  14. Nondestructive techniques for the control of conditioned radioactive wastes

    International Nuclear Information System (INIS)

    Delprato, U.

    1987-01-01

    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

  15. Nuclear techniques in the control of parasitic infections

    International Nuclear Information System (INIS)

    Mulligan, W.

    1976-01-01

    The development of radiation-attenuated vaccines against economically important parasitic diseases of farm animals has met with mixed success. Examples are presented ranging from the highly effective and much used commercial vaccine against cattle lungworm to the almost completely unsuccessful attempts to immunize sheep against liver fluke. The results presented emphasize that this approach is likely to be successful only if there is evidence of a strong degree of acquired immunity to the natural infection. The extension of immunological control to those systems where the parasite provokes only a modest resistance by the host will probably depend on a much greater understanding of the mechanism of the immune response. Such fundamental studies are likely to rely heavily on nuclear techniques, e.g. in the labelling of antigens, antibodies and parasites with radioactive isotopes. (author)

  16. Site characterization techniques used in environmental remediation activities

    International Nuclear Information System (INIS)

    Kostelnik, K.M.

    2000-01-01

    As a result of decades of nuclear energy research, weapons production, as well as ongoing operations, a significant amount of radioactive contamination has occurred throughout the United States Department of Energy (DOE) complex. DOE facility are in the process of assessing and potentially remediating various sites according to the regulations imposed by a Federal Facility Agreement and Consent order (FFA/CO) between DOE, the state in which the facility is located, and the U.S. Environmental Protection Agency (EPA). In support of these active site remediation efforts, the DOE has devoted considerable resources towards the development of innovative site characterization techniques that support environmental restoration activities. These resources and efforts have focused on various aspects of this complex problem. Research and technology development conducted at the Idaho National Engineering and Environmental Laboratory (INEEL) has resulted in the ability and state-of-the-art equipment required to obtain real-time, densely spaced, in situ characterization data (i.e. detection, speciation, and location) of various radionuclides and contaminants. The Remedial Action Monitoring System (RAMS), developed by the INEEL, consists of enhanced sensor technology, measurement modeling and interpretation techniques, and a suite of deployment platforms which can be interchanged to directly support remedial cleanup and site verification operations. In situ characterization techniques have advanced to the point where they are being actively deployed in support of remedial operations. The INEEL has deployed its system at various DOE and international sites. The deployment of in situ characterization systems during environmental restoration operations has shown that this approach results in several significant benefits versus conventional sampling techniques. A flexible characterization system permits rapid modification to satisfy physical site conditions, available site resources

  17. Application of Shark Skin Flow Control Techniques to Airflow

    Science.gov (United States)

    Morris, Jackson Alexander

    Due to millions of years of evolution, sharks have evolved to become quick and efficient ocean apex predators. Shark skin is made up of millions of microscopic scales, or denticles, that are approximately 0.2 mm in size. Scales located on the shark's body where separation control is paramount (such as behind the gills or the trailing edge of the pectoral fin) are capable of bristling. These scales are hypothesized to act as a flow control mechanism capable of being passively actuated by reversed flow. It is believed that shark scales are strategically sized to interact with the lower 5% of a boundary layer, where reversed flow occurs at the onset of boundary layer separation. Previous research has shown shark skin to be capable of controlling separation in water. This thesis aims to investigate the same passive flow control techniques in air. To investigate this phenomenon, several sets of microflaps were designed and manufactured with a 3D printer. The microflaps were designed in both 2D (rectangular) and 3D (mirroring shark scale geometry) variants. These microflaps were placed in a low-speed wind tunnel in the lower 5% of the boundary layer. Solid fences and a flat plate diffuser with suction were placed in the tunnel to create different separated flow regions. A hot film probe was used to measure velocity magnitude in the streamwise plane of the separated regions. The results showed that low-speed airflow is capable of bristling objects in the boundary layer. When placed in a region of reverse flow, the microflaps were passively actuated. Microflaps fluctuated between bristled and flat states in reverse flow regions located close to the reattachment zone.

  18. 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

  19. WHO activities in teaching radioimmunoassay and related techniques

    International Nuclear Information System (INIS)

    Goncharov, N.P.; Sufi, S.B.; Donaldson, A.; Jeffcoate, S.L.

    1986-01-01

    The Special Programme of Research, Development and Research Training in Human Reproduction of the World Health Organization has recognized from its beginning that training is a key component of its activities, including its immunoassay standardization programme. Since the start of the Special Programme more than 250 scientists have received training in RIA and related procedures and 27 training courses have been held in various countries. Many of the courses have been held in collaboration with the International Atomic Energy Agency, and these co-operative activities have established a core of scientific expertise worldwide which has contributed to the increased availability of modern diagnostic techniques in many countries. The increasing number of medical and non-medical applications of immunoassays and the special expertise required for some immunoassay methods create a continuing demand for training in RIA techniques. Both WHO and the IAEA have responded by organizing courses to 'train the trainers' and by supporting national and regional courses based on centrally provided material, as well as by commissioning the production of additional teaching documents and audio-visual aids in English and Spanish. It is envisaged that such materials, complete with centrally provided materials for practicals and other teaching aids, will be made available to national reagent programmes and will be used in the future as a well characterized, standardized core around which local organizers can construct training programmes geared to local needs and drawing upon local experience. (author)

  20. 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.

  1. Improving Accuracy of Processing by Adaptive Control Techniques

    Directory of Open Access Journals (Sweden)

    N. N. Barbashov

    2016-01-01

    Full Text Available When machining the work-pieces a range of scatter of the work-piece dimensions to the tolerance limit is displaced in response to the errors. To improve an accuracy of machining and prevent products from defects it is necessary to diminish the machining error components, i.e. to improve the accuracy of machine tool, tool life, rigidity of the system, accuracy of adjustment. It is also necessary to provide on-machine adjustment after a certain time. However, increasing number of readjustments reduces the performance and high machine and tool requirements lead to a significant increase in the machining cost.To improve the accuracy and machining rate, various devices of active control (in-process gaging devices, as well as controlled machining through adaptive systems for a technological process control now become widely used. Thus, the accuracy improvement in this case is reached by compensation of a majority of technological errors. The sensors of active control can provide improving the accuracy of processing by one or two quality classes, and simultaneous operation of several machines.For efficient use of sensors of active control it is necessary to develop the accuracy control methods by means of introducing the appropriate adjustments to solve this problem. Methods based on the moving average, appear to be the most promising for accuracy control, since they contain information on the change in the last several measured values of the parameter under control.When using the proposed method in calculation, the first three members of the sequence of deviations remain unchanged, therefore 1 1 x  x , 2 2 x  x , 3 3 x  x Then, for each i-th member of the sequence we calculate that way: , ' i i i x  x  k x , where instead of the i x values will be populated with the corresponding values ' i x calculated as an average of three previous members:3 ' 1  2  3  i i i i x x x x .As a criterion for the estimate of the control

  2. Monitoring and controlling ovarian activity in elephants.

    Science.gov (United States)

    Thitaram, Chatchote; Brown, Janine L

    2018-03-15

    Both Asian (Elephas maximus) and African (Loxodonta africana) elephants are important keystone, umbrella and flagship species. Paradoxically, world population numbers of both species are declining in many of their natural ranges due mainly to poaching, while over population of elephants in some areas is resulting in serious human-elephant conflict, and modifications of natural habitats that impact biodiversity. Understanding mechanisms of reproductive control is vital to effective population management, and for that reason significant advances have been made in endocrine and ultrasonographic monitoring techniques, particularly in studies of elephants ex situ. However, there remains a need to develop new methods to control ovarian activity, both for enhancing and inhibiting reproduction, to maintain population numbers at levels that ensure species survival and their ability to safely cohabitate with humans and other species. We present an overview of reproductive monitoring methods and how they have contributed to our knowledge of elephant reproductive biology, as well as their application for in situ and ex situ conservation purposes. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Active control of noise radiation from vibrating structures

    DEFF Research Database (Denmark)

    Mørkholt, Jakob

    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...... optimal and robust discrete-time feedback controllers for active vibration control of multimodal structures have been compared. They have been showed to yield controllers with identical frequency response characteristics, even though they employ completely different methods of numerical solutions...... and result in different representations of the controllers. The Internal Model Control structure combined with optimal filtering is suggested as an alternative to state space optimal control techniques for designing robust optimal controllers for audio frequency vibration control of resonant structures....

  4. [Amnioinfusion: techniques, indications, and controlled retrospective study of 55 cases].

    Science.gov (United States)

    Gramellini, D; Fieni, S; Piantelli, G; Faiola, S; Kaihura, C; Verrotti, C; Cavallotti, D; Viola, P; Bacchini, G; Vadora, E

    2000-01-01

    Amnioinfusion is a relatively recent procedure introduced among fetal medicine techniques. Its applications focus on two different methods: transcervical and transabdominal. The first procedure usually is carried out during "intrapartum amnioinfusion" to prevent or treat fetal heart rate (FHR) decelerations related to oligohydramnios or to dilute thick meconium staining of the amniotic fluid. The latter method used during "antepartum amnioinfusion" is usually indicated for severe oligohydramnios in order to avoid the complications related such as pulmonary hypoplasia, deforming effects of oligohydramnios, variable FHR decelerations and intraventricular hemorrhages. Antepartum amnioinfusion, also used to improve ultrasound visualisation in presence of oligohydramnios, is less employed as compared to intrapartum amnioinfusion, therefore its risks are not well established. In order to study possible adverse effects on the mother or foetus, fifty five patients affected by oligohydramnios at 17th-34th week of gestational age were submitted to antepartum amnioinfusion (1-5 procedures) and were matched retrospectively with forty seven women with the same characteristics treated with the conservative and expectant management. The trend of pregnancy was the same for both groups in relation to maternal fever > 38 degrees (10.9% in the amnioinfused group vs 17.0% in control group ns), leukocyte count > 18,000/mm3 (25.5% vs 21.3%, ns), C-reactive protein > 10 ng/ml (10.9% vs 6.4%, ns). The latency period between admission and delivery was significantly longer in the amnioinfused group than in the control one [21 (range 1-98) vs 9 days (range 0-72); p amnioinfused group than in the control group (32.3% vs 66.6%; p amnioinfusion seems to increase the latency period between premature rupture of membranes and delivery, but it remains to clarify if this procedure is as much safe for the fetus as for the mother.

  5. The effects of the Bowen technique on hamstring flexibility over time: a randomised controlled trial.

    Science.gov (United States)

    Marr, Michelle; Baker, Julian; Lambon, Nicky; Perry, Jo

    2011-07-01

    The hamstring muscles are regularly implicated in recurrent injuries, movement dysfunction and low back pain. Links between limited flexibility and development of neuromusculoskeletal symptoms are frequently reported. The Bowen Technique is used to treat many conditions including lack of flexibility. The study set out to investigate the effect of the Bowen Technique on hamstring flexibility over time. An assessor-blind, prospective, randomised controlled trial was performed on 120 asymptomatic volunteers. Participants were randomly allocated into a control group or Bowen group. Three flexibility measurements occurred over one week, using an active knee extension test. The intervention group received a single Bowen treatment. A repeated measures univariate analysis of variance, across both groups for the three time periods, revealed significant within-subject and between-subject differences for the Bowen group. Continuing increases in flexibility levels were observed over one week. No significant change over time was noted for the control group. Copyright © 2010 Elsevier Ltd. All rights reserved.

  6. Controller Design of DFIG Based Wind Turbine by Using Evolutionary Soft Computational Techniques

    Directory of Open Access Journals (Sweden)

    O. P. Bharti

    2017-06-01

    Full Text Available This manuscript illustrates the controller design for a doubly fed induction generator based variable speed wind turbine by using a bioinspired scheme. This methodology is based on exploiting two proficient swarm intelligence based evolutionary soft computational procedures. The particle swarm optimization (PSO and bacterial foraging optimization (BFO techniques are employed to design the controller intended for small damping plant of the DFIG. Wind energy overview and DFIG operating principle along with the equivalent circuit model is adequately discussed in this paper. The controller design for DFIG based WECS using PSO and BFO are described comparatively in detail. The responses of the DFIG system regarding terminal voltage, current, active-reactive power, and DC-Link voltage have slightly improved with the evolutionary soft computational procedure. Lastly, the obtained output is equated with a standard technique for performance improvement of DFIG based wind energy conversion system.

  7. Proton-activation technique for the determination of antimony

    International Nuclear Information System (INIS)

    Krivan, V.; Barth, P.

    1979-01-01

    Photon-activation analysis has been applied to the determination of antimony. Thick-target yields and analytical sensitivities are given for the indicator-radionuclides sup(119m)Te, sup(119g)Te, sup(121m)Te, sup(121g)Te, sup(123m)Te, sup(120m)Sb and sup(122g)Sb for proton energies between 9 and 25 MeV. In irradiations with a 5-μA beam for 5 hr, followed by a specific separation of the indicator-radionuclides, limits of detection at the ppm level can be achieved. Data are given for the most significant interfering reactions. Antimony was determined instrumentally in bismuth of very pure grade and the results are compared with those obtained from two independent techniques. (author)

  8. 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

  9. Enhancing spill prevention and response preparedness through quality control techniques

    International Nuclear Information System (INIS)

    Jones, M.A.; Butts, R.L.; Pickering, T.H.; Lindsay, J.R.; McCully, B.S.

    1993-01-01

    The year 1990 saw passage of federal and state oil spill legislation directing the US Environmental Protection Agency and the Florida Department of Environmental Regulation to require on shore bulk petroleum storage facilities to improve their oil spill response and prevention capabilities. The Florida Power ampersand Light Company (FPL), to address concerns arising out of several recent significant spills which had occurred worldwide, and to examine its current situation with regard compliance with the new laws, formed a quality improvement interdepartmental task team in July 1989. Its mission was to reduce the potential for oil spills during waterborne transportation between FPL's fuel oil terminals and its power plants and during transfer and storage of oil at these facilities. Another objective of the team was to enhance the company's spill response preparedness. Using quality control tools and reliability techniques, the team conducted a detailed analysis of seven coastal power plants and five fuel oil terminal facilities. This analysis began with the development of cause-and-effect diagrams designed to identify the root causes of spills so that corrective and preventive actions could be taken. These diagram are constructed by listing possible causes of oil spills under various major categories of possible system breakdown, such as man, method, equipment, and materials. Next, potential root causes are identified and then verified. The team identified the occurrence of surface water oil spill and reduced spill response capability as primary concerns and accordingly constructed cause-and-effect diagrams for both components. Lack of proper procedures, failure of control equipment, and inadequate facility design were identified as potential root causes leading to surface water oil spills. Lack of proper procedures, an inconsistent training program, and response equipment limitations were identified as potential root causes affecting oil spill response capabilities

  10. Prevalence of active trachoma two years after control activities ...

    African Journals Online (AJOL)

    The prevalence of TF/TI showed significant reduction (p-value <0.001) in all five districts and overall in the two regions. Conclusion: Trachoma control activities over a two-year period in two regions in Ghana had led to significant reduction in the prevalence of active disease. Integrated surveillance and active monitoring will ...

  11. Satellite Dynamic Damping via Active Force Control Augmentation

    Science.gov (United States)

    Varatharajoo, Renuganth

    2012-07-01

    An approach that incorporates the Active Force Control (AFC) technique into a conventional Proportional-Derivative (PD) controller is proposed for a satellite active dynamic damping towards a full attitude control. The AFC method has been established to facilitate a robust motion control of dynamical systems in the presence of disturbances, parametric uncertainties and changes that are commonly prevalent in the real-world environment. The usefulness of the method can be extended by introducing intelligent mechanisms to approximate the mass or inertia matrix of the dynamic system to trigger the compensation effect of the controller. AFC is a technique that relies on the appropriate estimation of the inertial or mass parameters of the dynamic system and the measurements of the acceleration and force signals induced by the system if practical implementation is ever considered. In AFC, it is shown that the system subjected to a number of disturbances remains stable and robust via the compensating action of the control strategy. We demonstrate that it is possible to design a spacecraft attitude feedback controller that will ensure the system dynamics set point remains unchanged even in the presence of the disturbances provided that the actual disturbances can be modeled effectively. In order to further facilitate this analysis, a combined energy and attitude control system (CEACS) is proposed as a model satellite attitude control actuator. All the governing equations are established and the proposed satellite attitude control architecture is made amenable to numerical treatments. The results show that the PD-AFC attitude damping performances are superiorly better than that of the solely PD type. It is also shown that the tunings of the AFC system gains are crucial to ensure a better attitude damping performance and this process is mandatory for AFC systems. Finally, the results demonstrate an important satellite dynamic damping enhancement capability using the AFC

  12. Elemental analysis of brazing alloy samples by neutron activation technique

    International Nuclear Information System (INIS)

    Eissa, E.A.; Rofail, N.B.; Hassan, A.M.; El-Shershaby, A.; Walley El-Dine, N.

    1996-01-01

    Two brazing alloy samples (C P 2 and C P 3 ) have been investigated by Neutron activation analysis (NAA) technique in order to identify and estimate their constituent elements. The pneumatic irradiation rabbit system (PIRS), installed at the first egyptian research reactor (ETRR-1) was used for short-time irradiation (30 s) with a thermal neutron flux of 1.6 x 10 1 1 n/cm 2 /s in the reactor reflector, where the thermal to epithermal neutron flux ratio is 106. Long-time irradiation (48 hours) was performed at reactor core periphery with thermal neutron flux of 3.34 x 10 1 2 n/cm 2 /s, and thermal to epithermal neutron flux ratio of 79. Activation by epithermal neutrons was taken into account for the (1/v) and resonance neutron absorption in both methods. A hyper pure germanium detection system was used for gamma-ray acquisitions. The concentration values of Al, Cr, Fe, Co, Cu, Zn, Se, Ag and Sb were estimated as percentages of the sample weight and compared with reported values. 1 tab

  13. Elemental analysis of brazing alloy samples by neutron activation technique

    Energy Technology Data Exchange (ETDEWEB)

    Eissa, E A; Rofail, N B; Hassan, A M [Reactor and Neutron physics Department, Nuclear Research Centre, Atomic Energy Authority, Cairo (Egypt); El-Shershaby, A; Walley El-Dine, N [Physics Department, Faculty of Girls, Ain Shams Universty, Cairo (Egypt)

    1997-12-31

    Two brazing alloy samples (C P{sup 2} and C P{sup 3}) have been investigated by Neutron activation analysis (NAA) technique in order to identify and estimate their constituent elements. The pneumatic irradiation rabbit system (PIRS), installed at the first egyptian research reactor (ETRR-1) was used for short-time irradiation (30 s) with a thermal neutron flux of 1.6 x 10{sup 1}1 n/cm{sup 2}/s in the reactor reflector, where the thermal to epithermal neutron flux ratio is 106. Long-time irradiation (48 hours) was performed at reactor core periphery with thermal neutron flux of 3.34 x 10{sup 1}2 n/cm{sup 2}/s, and thermal to epithermal neutron flux ratio of 79. Activation by epithermal neutrons was taken into account for the (1/v) and resonance neutron absorption in both methods. A hyper pure germanium detection system was used for gamma-ray acquisitions. The concentration values of Al, Cr, Fe, Co, Cu, Zn, Se, Ag and Sb were estimated as percentages of the sample weight and compared with reported values. 1 tab.

  14. Tracing salmon to their birthplace by activable tracer technique

    International Nuclear Information System (INIS)

    Shibuya, Masao

    1978-01-01

    Activable tracer technique was applied to trace the recurrent migration of white salmons, as a typical example of employing radioactivation analysis to the study of agricultural and marinefields. Europium was adopted because it is easy to use technically with less influence on fish body and easy to detect, and its remaining time is very long. Artificially hatched young white salmons were stocked in the Saibetsu River after being raised for a month with europium-containing feed. These stocked fish were labeled by fin-cutting method. Recurrent salmons (fin cutting-labeled fish) were then collected and dissected. The fishes were divided into otoliths, scales, flesh, internal organs, gills, bones, etc., and irradiated for 5 min in JRR-2 reactor of Japan Atomic Energy Research Institute. Europium was detected from the scales and otoliths of 3 to 4 year stocked adult fishes by γ-spectrometry of Eu. This proved the availability of activable tracer method for tracing the recurrent migration of salmons. (Kobatake, H.)

  15. Active Control Of Structure-Borne Noise

    Science.gov (United States)

    Elliott, S. J.

    1994-11-01

    The successful practical application of active noise control requires an understanding of both its acoustic limitations and the limitations of the electrical control strategy used. This paper is concerned with the active control of sound in enclosures. First, a review is presented of the fundamental physical limitations of using loudspeakers to achieve either global or local control. Both approaches are seen to have a high frequency limit, due to either the acoustic modal overlap, or the spatial correlation function of the pressure field. These physical performance limits could, in principle, be achieved with either a feedback or a feedforward control strategy. These strategies are reviewed and the use of adaptive digital filters is discussed for both approaches. The application of adaptive feedforward control in the control of engine and road noise in cars is described. Finally, an indirect approach to the active control of sound is discussed, in which the vibration is suppressed in the structural paths connecting the source of vibration to the enclosure. Two specific examples of this strategy are described, using an active automotive engine mount and the incorporation of actuators into helicopter struts to control gear-meshing tones. In both cases good passive design can minimize the complexity of the active controller.

  16. Systematic review of behaviour change techniques to promote participation in physical activity among people with dementia.

    Science.gov (United States)

    Nyman, Samuel R; Adamczewska, Natalia; Howlett, Neil

    2018-02-01

    The objective of this study was to systematically review the evidence for the potential promise of behaviour change techniques (BCTs) to increase physical activity among people with dementia (PWD). PsychINFO, MEDLINE, CINAHL, and the Cochrane Central Register of Controlled Trials databases were searched 01/01/2000-01/12/2016. Randomized controlled/quasi-randomized trials were included if they recruited people diagnosed/suspected to have dementia, used at least one BCT in the intervention arm, and had at least one follow-up measure of physical activity/adherence. Studies were appraised using the Cochrane Collaboration Risk of Bias Tool, and BCTs were coded using Michie et al., 2013, Annals of Behavioral Medicine, 46, 81. taxonomy. Intervention findings were narratively synthesized as either 'very promising', 'quite promising', or 'non-promising', and BCTs were judged as having potential promise if they featured in at least twice as many very/quite promising than non-promising interventions (as per Gardner et al., 2016, Health Psychology Review, 10, 89). Nineteen articles from nine trials reported physical activity findings on behavioural outcomes (two very promising, one quite promising, and two non-promising) or intervention adherence (one quite promising and four non-promising). Thirteen BCTs were used across the interventions. While no BCT had potential promise to increase intervention adherence, three BCTs had potential promise for improving physical activity behaviour outcomes: goal setting (behaviour), social support (unspecified), and using a credible source. Three BCTs have potential promise for use in future interventions to increase physical activity among PWD. Statement of contribution What is already known on this subject? While physical activity is a key lifestyle factor to enhance and maintain health and wellbeing amongst the general population, adults rarely participate in sufficient levels to obtain these benefits. Systematic reviews suggest that

  17. 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.

  18. Reusable Launch Vehicle Attitude Control Using a Time-Varying Sliding Mode Control Technique

    Science.gov (United States)

    Shtessel, Yuri B.; Zhu, J. Jim; Daniels, Dan; Jackson, Scott (Technical Monitor)

    2002-01-01

    In this paper we present a time-varying sliding mode control (TVSMC) technique for reusable launch vehicle (RLV) attitude control in ascent and entry flight phases. In ascent flight the guidance commands Euler roll, pitch and yaw angles, and in entry flight it commands the aerodynamic angles of bank, attack and sideslip. The controller employs a body rate inner loop and the attitude outer loop, which are separated in time-scale by the singular perturbation principle. The novelty of the TVSMC is that both the sliding surface and the boundary layer dynamics can be varied in real time using the PD-eigenvalue assignment technique. This salient feature is used to cope with control command saturation and integrator windup in the presence of severe disturbance or control effector failure, which enhances the robustness and fault tolerance of the controller. The TV-SMC ascent and descent designs are currently being tested with high fidelity, 6-DOF dispersion simulations. The test results will be presented in the final version of this paper.

  19. Thermal stress mitigation by Active Thermal Control

    DEFF Research Database (Denmark)

    Soldati, Alessandro; Dossena, Fabrizio; Pietrini, Giorgio

    2017-01-01

    This work proposes an Active Thermal Control (ATC) of power switches. Leveraging on the fact that thermal stress has wide impact on the system reliability, controlling thermal transients is supposed to lengthen the lifetime of electronic conversion systems. Indeed in some environments...... results of control schemes are presented, together with evaluation of the proposed loss models. Experimental proof of the ability of the proposed control to reduce thermal swing and related stress on the device is presented, too....

  20. 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.)

  1. Changes in muscle activation following balance and technique training and a season of Australian football.

    Science.gov (United States)

    Donnelly, C J; Elliott, B C; Doyle, T L A; Finch, C F; Dempsey, A R; Lloyd, D G

    2015-05-01

    Determine if balance and technique training implemented adjunct to 1001 male Australian football players' training influenced the activation/strength of the muscles crossing the knee during pre-planned and unplanned sidestepping. Randomized Control Trial. Each Australian football player participated in either 28 weeks of balance and technique training or 'sham' training. Twenty-eight Australian football players (balance and technique training, n=12; 'sham' training, n=16) completed biomechanical testing pre-to-post training. Peak knee moments and directed co-contraction ratios in three degrees of freedom, as well as total muscle activation were calculated during pre-planned and unplanned sidestepping. No significant differences in muscle activation/strength were observed between the 'sham' training and balance and technique training groups. Following a season of Australian football, knee extensor (p=0.023) and semimembranosus (p=0.006) muscle activation increased during both pre-planned sidestepping and unplanned sidestepping. Following a season of Australian football, total muscle activation was 30% lower and peak valgus knee moments 80% greater (p=0.022) during unplanned sidestepping when compared with pre-planned sidestepping. When implemented in a community level training environment, balance and technique training was not effective in changing the activation of the muscles crossing the knee during sidestepping. Following a season of Australian football, players are better able to support both frontal and sagittal plane knee moments. When compared to pre-planned sidestepping, Australian football players may be at increased risk of anterior cruciate ligament injury during unplanned sidestepping in the latter half of an Australian football season. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  2. Chaos synchronization in a Josephson junction system via active sliding mode control

    International Nuclear Information System (INIS)

    Zhao Yang; Wang Wei

    2009-01-01

    In this letter, two types of active siding control methods are proposed and applied to achieve chaotic synchronization in a Josephson junction system. Numerical simulations are used to verify the proposed control techniques.

  3. 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...... active filter. Simulation and experimental results obtained in laboratory confirmed the validity and effectiveness of the control....

  4. Manually controlled neutron-activation system

    International Nuclear Information System (INIS)

    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

  5. 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.

  6. Improved mesh based photon sampling techniques for neutron activation analysis

    International Nuclear Information System (INIS)

    Relson, E.; Wilson, P. P. H.; Biondo, E. D.

    2013-01-01

    The design of fusion power systems requires analysis of neutron activation of large, complex volumes, and the resulting particles emitted from these volumes. Structured mesh-based discretization of these problems allows for improved modeling in these activation analysis problems. Finer discretization of these problems results in large computational costs, which drives the investigation of more efficient methods. Within an ad hoc subroutine of the Monte Carlo transport code MCNP, we implement sampling of voxels and photon energies for volumetric sources using the alias method. The alias method enables efficient sampling of a discrete probability distribution, and operates in 0(1) time, whereas the simpler direct discrete method requires 0(log(n)) time. By using the alias method, voxel sampling becomes a viable alternative to sampling space with the 0(1) approach of uniformly sampling the problem volume. Additionally, with voxel sampling it is straightforward to introduce biasing of volumetric sources, and we implement this biasing of voxels as an additional variance reduction technique that can be applied. We verify our implementation and compare the alias method, with and without biasing, to direct discrete sampling of voxels, and to uniform sampling. We study the behavior of source biasing in a second set of tests and find trends between improvements and source shape, material, and material density. Overall, however, the magnitude of improvements from source biasing appears to be limited. Future work will benefit from the implementation of efficient voxel sampling - particularly with conformal unstructured meshes where the uniform sampling approach cannot be applied. (authors)

  7. In vivo measurements of nitrogen using a neutron activation technique

    International Nuclear Information System (INIS)

    Larsson, L.; Alpsten, M.; Toelli, J.; Drugge, N.; Mattsson, S.

    1986-01-01

    Knowledge of body composition is essential for understanding of many diseases such as obesity, anorexia, cancer, kidney and heart diseases. For many years, total body potassium (TBK) has been used as an estimate of the intracellular protein. In some diseases intracellular- and extracellular protein may vary significantly. Together with TBK, total body nitrogen (TBN) should in these cases be measured to estimate the total protein content. The nitrogen content can be measured by in vivo neutron activation. In this work the authors have used the prompt gamma technique: Thermalized neutrons from a Cf-252-source are captured in (n, δ)-reactions. Prompt 10.8 MeV photons are emitted and can be detected during irradiation. The source is contained in a polyethylene block which forms a collimator surrounded by a phi 1.40 m x 0.80 m water tank. The patient is irradiated from below by a 15 cm x 50 cm neutron field. It is possible to scan the whole patient or to measure a part of the body. A phi 15 cm x 15 cm NaI(T1)-detector is used for detection of the 10.8 MeV photons. The detector is mounted above the patient outside the neutron field

  8. 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.

  9. 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.

  10. 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.

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

    International Nuclear Information System (INIS)

    Macasek, F.; Buriova, E.; Bruder, 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-[ 18 F]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.HCO 2 - 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 NH 4 + at m/z 394. Expired FDG injection samples contain decomposition products from which at least one labelled by 18 F 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 [ 18 O]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 18 F makes this inconsistent. Quantification and validation of the FDG component analysis is under way. (author)

  12. Machine throughput improvement achieved using innovative control technique

    International Nuclear Information System (INIS)

    Sharma, V.; Acharya, S.; Mittal, K.C.

    2012-01-01

    In any type of fully or semi automatic machine the control systems plays an important role. The control system on the one hand has to consider the human psychology, intelligence requirement for an operator, and attention needed from him. On the other hand the complexity of the control has also to be understood well before designing a control system that can be handled comfortably and safely by the operator. As far as the user experience/comfort is concerned the design of control system GUI is vital. Considering these two aspects related to the user of the machine it is evident that the control system design is very important because it is has to accommodate the human behaviour and skill sets required/available as well as the capability of the machine under the control of the control system. An intelligently designed control system can enhance the productivity of the machine. (author)

  13. 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.

  14. A comprehensive overview of hybrid electric vehicle: Powertrain configurations, powertrain control techniques and electronic control units

    Energy Technology Data Exchange (ETDEWEB)

    Cagatay Bayindir, Kamil; Goezuekuecuek, Mehmet Ali; Teke, Ahmet [Cukurova University, Department of Electrical and Electronics Engineering, Balcali, Saricam, Adana (Turkey)

    2011-02-15

    The studies for hybrid electrical vehicle (HEV) have attracted considerable attention because of the necessity of developing alternative methods to generate energy for vehicles due to limited fuel based energy, global warming and exhaust emission limits in the last century. HEV incorporates internal composition engine, electric machines and power electronic equipments. In this study, overview of HEVs with a focus on hybrid configurations, energy management strategies and electronic control units are presented. Advantages and disadvantages of each configuration are clearly emphasized. The existing powertrain control techniques for HEVs are classified and comprehensively described. Electronic control units used in HEV configuration are also elaborated. The latest trends and technological challenges in the near future for HEVs are discussed. (author)

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

    International Nuclear Information System (INIS)

    Carvalho, Breno Carnevalli Franco de

    2003-01-01

    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)

  16. Nonlinear systems techniques for dynamical analysis and control

    CERN Document Server

    Lefeber, Erjen; Arteaga, Ines

    2017-01-01

    This treatment of modern topics related to the control of nonlinear systems is a collection of contributions celebrating the work of Professor Henk Nijmeijer and honoring his 60th birthday. It addresses several topics that have been the core of Professor Nijmeijer’s work, namely: the control of nonlinear systems, geometric control theory, synchronization, coordinated control, convergent systems and the control of underactuated systems. The book presents recent advances in these areas, contributed by leading international researchers in systems and control. In addition to the theoretical questions treated in the text, particular attention is paid to a number of applications including (mobile) robotics, marine vehicles, neural dynamics and mechanical systems generally. This volume provides a broad picture of the analysis and control of nonlinear systems for scientists and engineers with an interest in the interdisciplinary field of systems and control theory. The reader will benefit from the expert participan...

  17. 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...

  18. Soft Computing Technique and Conventional Controller for Conical Tank Level Control

    Directory of Open Access Journals (Sweden)

    Sudharsana Vijayan

    2016-03-01

    Full Text Available In many process industries the control of liquid level is mandatory. But the control of nonlinear process is difficult. Many process industries use conical tanks because of its non linear shape contributes better drainage for solid mixtures, slurries and viscous liquids. So, control of conical tank level is a challenging task due to its non-linearity and continually varying cross-section. This is due to relationship between controlled variable level and manipulated variable flow rate, which has a square root relationship. The main objective is to execute the suitable controller for conical tank system to maintain the desired level. System identification of the non-linear process is done using black box modelling and found to be first order plus dead time (FOPDT model. In this paper it is proposed to obtain the mathematical modelling of a conical tank system and to study the system using block diagram after that soft computing technique like fuzzy and conventional controller is also used for the comparison.

  19. 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.

  20. 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

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

    International Nuclear Information System (INIS)

    Argiles Herrero, R.

    2011-01-01

    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)

  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. Software factory techniques applied to process control at CERN

    OpenAIRE

    Dutour, Mathias D

    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 inf...

  4. 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....../kg. Measurement compatibility is obtained by control of traceability to certified reference materials, (C) 1994 Wiley-Liss, Inc....

  5. Diagnostic techniques used in controlled thermonuclear research at Harwell

    Energy Technology Data Exchange (ETDEWEB)

    Harding, G N; Dellis, A N; Gibson, A; Jones, B; Lees, D J; McWhirter, R W.P.; Ramsden, S A; Ward, S [UK Atomic Energy Authority, AERE, Harwell (United Kingdom)

    1958-07-01

    This paper is a general survey of the lines along which diagnostic methods (spectroscopy, electrical measurements, and the study of high energy radiations) are developing at Harwell, and indicates the results which have been obtained so far. Many of the techniques are in a rudimentary state, and most of the Zeta experiments are incomplete.

  6. 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...

  7. 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...

  8. Applications of adaptive filters in active noise control

    Science.gov (United States)

    Darlington, Paul

    The active reduction of acoustic noise is achieved by the addition of a cancelling acoustic signal to the unwanted sound. Successful definition of the cancelling signal amounts to a system identification problem. Recent advances in adaptive signal processing have allowed this problem to be tackled using adaptive filters, which offer significant advantages over conventional solutions. The extension of adaptive noise cancelling techniques, which were developed in the electrical signal conditioning context, to the control of acoustic systems is studied. An analysis is presented of the behavior of the Widrow-Hoff LMS adaptive noise canceller with a linear filter in its control loop. The active control of plane waves propagating axially in a hardwalled duct is used as a motivating model problem. The model problem also motivates the study of the effects of feedback around an LMS adaptive filter. An alternative stochastic gradient algorithm for controlling adaptive filters in the presence of feedback is presented.

  9. Modeling and Control of Multivariable Process Using Intelligent Techniques

    Directory of Open Access Journals (Sweden)

    Subathra Balasubramanian

    2010-10-01

    Full Text Available For nonlinear dynamic systems, the first principles based modeling and control is difficult to implement. In this study, a fuzzy controller and recurrent fuzzy controller are developed for MIMO process. Fuzzy logic controller is a model free controller designed based on the knowledge about the process. In fuzzy controller there are two types of rule-based fuzzy models are available: one the linguistic (Mamdani model and the other is Takagi–Sugeno model. Of these two, Takagi-Sugeno model (TS has attracted most attention. The fuzzy controller application is limited to static processes due to their feedforward structure. But, most of the real-time processes are dynamic and they require the history of input/output data. In order to store the past values a memory unit is needed, which is introduced by the recurrent structure. The proposed recurrent fuzzy structure is used to develop a controller for the two tank heating process. Both controllers are designed and implemented in a real time environment and their performance is compared.

  10. Hierarchical control of a nuclear reactor using uncertain dynamics techniques

    International Nuclear Information System (INIS)

    Rovere, L.A.; Otaduy, P.J.; Brittain, C.R.; Perez, R.B.

    1988-01-01

    Recent advances in the nonlinear optimal control area are opening new possibilities towards its implementation in process control. Algorithms for multivariate control, hierarchical decomposition, parameter tracking, model uncertainties actuator saturation effects and physical limits to state variables can be implemented on the basis of a consistent mathematical formulation. In this paper, good agreement is shown between a centralized and a hierarchical implementation of a controller for a hypothetical nuclear power plant subject to multiple demands. The performance of the hierarchical distributed system in the presence of localized subsystem failures is analyzed. 4 refs., 13 figs

  11. 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.

  12. Active Vibration Control of Hydrodynamic Journal Bearings

    Science.gov (United States)

    Tůma, J.; Šimek, J.; Škuta, J.; Los, J.; Zavadil, J.

    Rotor instability is one of the most serious problems of high-speed rotors supported by sliding bearings. With constantly increasing parameters, new machines problems with rotor instability are encountered more and more often. Even though there are many solutions based on passive improvement of the bearing geometry to enlarge the operational speed range of the journal bearing, the paper deals with a working prototype of a system for the active vibration control of journal bearings with the use of piezoactuators. The actively controlled journal bearing consists of a movable bushing, which is actuated by two piezoactuators. It is assumed that the journal vibration is measured by a pair of proximity probes. Force produced by piezoactuators and acting at the bushing is controlled according to error signals derived from the proximity probe output signals. The active vibration control was tested with the use of a test rig, which consists of a rotor supported by two controllable journal bearings and driven by an inductive motor up to 23,000 rpm. As it was proved by experiments the active vibration control extends considerably the range of the rotor operational speed.

  13. Active noise control in a duct to cancel broadband noise

    Science.gov (United States)

    Chen, Kuan-Chun; Chang, Cheng-Yuan; Kuo, Sen M.

    2017-09-01

    The paper presents cancelling duct noises by using the active noise control (ANC) techniques. We use the single channel feed forward algorithm with feedback neutralization to realize ANC. Several kinds of ducts noises including tonal noises, sweep tonal signals, and white noise had investigated. Experimental results show that the proposed ANC system can cancel these noises in a PVC duct very well. The noise reduction of white noise can be up to 20 dB.

  14. Rovibrational controlled-NOT gates using optimized stimulated Raman adiabatic passage techniques and optimal control theory

    International Nuclear Information System (INIS)

    Sugny, D.; Bomble, L.; Ribeyre, T.; Dulieu, O.; Desouter-Lecomte, M.

    2009-01-01

    Implementation of quantum controlled-NOT (CNOT) gates in realistic molecular systems is studied using stimulated Raman adiabatic passage (STIRAP) techniques optimized in the time domain by genetic algorithms or coupled with optimal control theory. In the first case, with an adiabatic solution (a series of STIRAP processes) as starting point, we optimize in the time domain different parameters of the pulses to obtain a high fidelity in two realistic cases under consideration. A two-qubit CNOT gate constructed from different assignments in rovibrational states is considered in diatomic (NaCs) or polyatomic (SCCl 2 ) molecules. The difficulty of encoding logical states in pure rotational states with STIRAP processes is illustrated. In such circumstances, the gate can be implemented by optimal control theory and the STIRAP sequence can then be used as an interesting trial field. We discuss the relative merits of the two methods for rovibrational computing (structure of the control field, duration of the control, and efficiency of the optimization).

  15. Bus-oriented digital control techniques in nuclear power plants

    International Nuclear Information System (INIS)

    Salm, M.

    1987-01-01

    The author states the conservative principles which govern the authorization procedures for nuclear reactor control systems. Using the example of a feedwater supply regulator, employing a digital, bus-oriented control system, he describes how the stigma attached to the word nuclear can be alleviated. (G.T.H.)

  16. 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...

  17. 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...

  18. Software factory techniques applied to process control at CERN

    CERN Document Server

    Dutour, Mathias D

    2008-01-01

    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, ...

  19. Controller tuning of district heating networks using experiment design techniques

    International Nuclear Information System (INIS)

    Dobos, Laszlo; Abonyi, Janos

    2011-01-01

    There are various governmental policies aimed at reducing the dependence on fossil fuels for space heating and the reduction in its associated emission of greenhouse gases. DHNs (District heating networks) could provide an efficient method for house and space heating by utilizing residual industrial waste heat. In such systems, heat is produced and/or thermally upgraded in a central plant and then distributed to the end users through a pipeline network. The control strategies of these networks are rather difficult thanks to the non-linearity of the system and the strong interconnection between the controlled variables. That is why a NMPC (non-linear model predictive controller) could be applied to be able to fulfill the heat demand of the consumers. The main objective of this paper is to propose a tuning method for the applied NMPC to fulfill the control goal as soon as possible. The performance of the controller is characterized by an economic cost function based on pre-defined operation ranges. A methodology from the field of experiment design is applied to tune the model predictive controller to reach the best performance. The efficiency of the proposed methodology is proven throughout a case study of a simulated NMPC controlled DHN. -- Highlights: → To improve the energetic and economic efficiency of a DHN an appropriate control system is necessary. → The time consumption of transitions can be shortened with the proper control system. → A NLMPC is proposed as control system. → The NLMPC is tuned by utilization of simplex methodology, using an economic oriented cost function. → The proposed NLMPC needs a detailed model of the DHN based on the physical description.

  20. An Advanced Control Technique for Floating Offshore Wind Turbines Based on More Compact Barge Platforms

    Directory of Open Access Journals (Sweden)

    Joannes Olondriz

    2018-05-01

    Full Text Available Hydrodynamic Floating Offshore Wind Turbine (FOWT platform specifications are typically dominated by seaworthiness and maximum operating platform-pitch angle-related requirements. However, such specifications directly impact the challenge posed by an FOWT in terms of control design. The conventional FOWT systems are typically based on large, heavy floating platforms, which are less likely to suffer from the negative damping effect caused by the excessive coupling between blade-pitch control and platform-pitch motion. An advanced control technique is presented here to increase system stability for barge type platforms. Such a technique mitigates platform-pitch motions and improves the generator speed regulation, while maintaining blade-pitch activity and reducing blade and tower loads. The NREL’s 5MW + ITI Energy barge reference model is taken as a basis for this work. Furthermore, the capabilities of the proposed controller for performing with a more compact and less hydrodynamically stable barge platform is analysed, with encouraging results.

  1. Quality control activities in the environmental radiology laboratory

    International Nuclear Information System (INIS)

    Llaurado, M.; Quesada, D.; Rauret, G.; Tent, J.; Zapata, D.

    2006-01-01

    During the last twenty years many analytical laboratories have implemented quality assurance systems. A quality system implementation requires documentation of all activities (technical and management), evaluation of these activities and its continual improvement. Implementation and adequate management of all the elements a quality system includes are not enough to guarantee quality of the analytical results generated at a time. That is the aim of a group of specific activities labelled as quality control activities. The Laboratori de Radiologia Ambiental (Environmental Radiology Laboratory; LRA) at the University of Barcelona was created in 1984 to carry out part of the quality control assays of the Environmental Radiology Monitoring Programs around some of the Spanish nuclear power plants, which are developed by the Servei Catala d'Activitats Energetiques (SCAR) and the Consejo de Seguridad Nuclear (CSN), organisations responsible for nuclear security and radiological protection. In these kind of laboratories, given the importance of the results they give, quality control activities become an essential aspect. In order to guarantee the quality of its analytical results, the LRA Direction decided to adopt the international standard UNE-EN ISO/IEC 17025 for its internal quality system and to accreditate some of the assays it carries out. In such as system, it is established, the laboratory shall monitor the validity of tests undertaken and data shall be recorded in such a way that trends are detectable. The present work shows the activities carried out in this way by the LRA, which are: Equipment control activities which in the special case of radiochemical techniques include measurement of backgrounds and blanks as well as periodical control of efficiency and resolution. Activities to assure the specifications settled by method validation, which are testing of reference materials and periodical analysis of control samples. Evaluation of the laboratory work quality

  2. Techniques for controlling variability in gram staining of obligate anaerobes.

    Science.gov (United States)

    Johnson, M J; Thatcher, E; Cox, M E

    1995-01-01

    Identification of anaerobes recovered from clinical samples is complicated by the fact that certain gram-positive anaerobes routinely stain gram negative; Peptostreptococcus asaccharolyticus, Eubacterium plautii, Clostridium ramosum, Clostridium symbiosum, and Clostridium clostridiiforme are among the nonconformists with regard to conventional Gram-staining procedures. Accurate Gram staining of American Type Culture Collection strains of these anaerobic bacteria is possible by implementing fixing and staining techniques within a gloveless anaerobic chamber. Under anaerobic conditions, gram-positive staining occurred in all test organisms with "quick" fixing techniques with both absolute methanol and formalin. The results support the hypothesis that, when anaerobic bacteria are exposed to oxygen, a breakdown of the physical integrity of the cell wall occurs, introducing Gram stain variability in gram-positive anaerobes. PMID:7538512

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

    International Nuclear Information System (INIS)

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

    2007-01-01

    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

  4. A fuzzy control technique for a magnetically levitated system

    Energy Technology Data Exchange (ETDEWEB)

    Lo Verso, G [C.N.R., Ce.Ri.S.E.P., Palermo (Italy); Trapanese, M [Dipt. di Ingegneria Elettrica, Univ. di Palermo (Italy)

    1996-12-31

    This paper presents the results of some analytical and numerical investigations on a control approach for magnetically leviated systems. This approach is based on fuzzy logic. It has been widely demonstrated that traditional control systems consent to maintain a stiff control on the air gap length. However, the traditional approaches could cause at very high speed, a vertical acceleration of the vehicle cabin larger than the maximum value currently allowed by the ISO standard. It is aim of this work to investigate the possibilities that a fuzzy controller offer in order to solve this problem. In order set up the controller, every mechanical degree of freedom is modelled in terms of some linguistic variables. These linguistic variables are described by several fuzzy sets. It must be noted that, doing so, the disturbances can be described in terms of fuzzy sets, too. A single-mass-model of the vehicle is considered in the paper. The features of the controller are numerically simulated under several types of disturbances and they are compared with a traditional control approach. It is shown how some parameters (especially the vertical acceleration) improve their behaviour. (orig.)

  5. Use of nuclear techniques in food, agriculture and pest control

    International Nuclear Information System (INIS)

    Sigurbjoernsson, B.

    1994-01-01

    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 it is possible to 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. The other type of application makes use of the unique ability of ionizing radiation x-rays, gamma-rays, electrons and neutrons to penetrate all types of matter and produce changes within living cells. These changes in cells induced by radiation can do three things: (1) can kill the cell; (2) render it incapable of reproducing itself (sterile); or (3) cause changes in its genetic make-up, called induced mutations. This paper contains a discussion of the applications of each technique

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

    International Nuclear Information System (INIS)

    Utterback, J.

    1993-09-01

    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

  7. Chapter 13 - Active Rectifiers and Their Control

    DEFF Research Database (Denmark)

    Davari, Pooya; Zare, Firuz; Abdelhakim, Ahmed

    2018-01-01

    This chapter investigates the control design of active rectifiers and their applications in power electronics-based power system. The harmonic emission and measures are firstly addressed as a basis of evaluating the active rectifier's effectiveness. Furthermore, the importance of new coming...... standards is highlighted. Application-oriented design of active rectifiers as a main reason behind evolvement of different topologies is discussed. Then, the main principle in designing different control schemes in single-phase and three-phase rectifiers is investigated, analyzed, and experimentally...... verified. The influence of nonideal operating conditions with possible solutions is addressed. Finally, future prospective of active rectifiers as a one of the key enabler of carbon-free power system is summarized....

  8. 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....

  9. Active versus passive screening for entrance control

    International Nuclear Information System (INIS)

    McCormick, N.J.

    1976-01-01

    The benefits of different entrance control actions are quantitatively assessed by defining a relative improvement index for the screening activity. Three classes of entrance control measures are investigated: the use of a purely active screening measure (such as a portal monitor), the use of a purely passive screening measure (such as personality typing), and the combined use of active and passive measures. Active entrance control measures have been studied previously [McCormick and Erdmann, Nucl. Mat. Manag. 4, (1975)] where it was determined that the relative improvement index is approximately related to the nondetection probability factor r for the protective system by (1-r + r ln r). It is shown here that the relative improvement index for a purely passive screening system also can be approximately expressed in a convenient manner. Because the probability is very small that a sabotage or diversion action would be attempted, the result for passive screening, multiplied by r, may be combined with the factor (1-r + r ln r) to give the relative improvement index for a combined, active-and-passive entrance control system. Results from simple example calculations indicate that passive screening of nuclear plant personnel or applicants for such positions is orders-of-magnitude less effective than portal monitors or reasonable improvements in them. 5 tables

  10. A Review of Field Corrosion Control and Monitoring Techniques of ...

    African Journals Online (AJOL)

    AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING ... to make informed decision and timely respond to corrosion threat before failures. Keywords: cathodic protection, corrosion mechanism, control and monitoring, ...

  11. Implementation of hybrid pollution control techniques to regulate the ...

    African Journals Online (AJOL)

    driniev

    1999-05-13

    May 13, 1999 ... regulate the metal finishing industries in the Ethekwini. Municipality ... ment processes, process control methodology and engineering design. ..... standards. There were many barriers that had to be overcome, the most.

  12. Novel Control Techniques for Hand and Wrist Robotic Rehabilitation

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed adaptive control in this proposal has applications in exoskeletons used for resistive exercises both during and after space missions, and in the...

  13. Active disturbance rejection controller for chemical reactor

    International Nuclear Information System (INIS)

    Both, Roxana; Dulf, Eva H.; Muresan, Cristina I.

    2015-01-01

    In the petrochemical industry, the synthesis of 2 ethyl-hexanol-oxo-alcohols (plasticizers alcohol) is of high importance, being achieved through hydrogenation of 2 ethyl-hexenal inside catalytic trickle bed three-phase reactors. For this type of processes the use of advanced control strategies is suitable due to their nonlinear behavior and extreme sensitivity to load changes and other disturbances. Due to the complexity of the mathematical model an approach was to use a simple linear model of the process in combination with an advanced control algorithm which takes into account the model uncertainties, the disturbances and command signal limitations like robust control. However the resulting controller is complex, involving cost effective hardware. This paper proposes a simple integer-order control scheme using a linear model of the process, based on active disturbance rejection method. By treating the model dynamics as a common disturbance and actively rejecting it, active disturbance rejection control (ADRC) can achieve the desired response. Simulation results are provided to demonstrate the effectiveness of the proposed method

  14. Active disturbance rejection controller for chemical reactor

    Energy Technology Data Exchange (ETDEWEB)

    Both, Roxana; Dulf, Eva H.; Muresan, Cristina I., E-mail: roxana.both@aut.utcluj.ro [Technical University of Cluj-Napoca, 400114 Cluj-Napoca (Romania)

    2015-03-10

    In the petrochemical industry, the synthesis of 2 ethyl-hexanol-oxo-alcohols (plasticizers alcohol) is of high importance, being achieved through hydrogenation of 2 ethyl-hexenal inside catalytic trickle bed three-phase reactors. For this type of processes the use of advanced control strategies is suitable due to their nonlinear behavior and extreme sensitivity to load changes and other disturbances. Due to the complexity of the mathematical model an approach was to use a simple linear model of the process in combination with an advanced control algorithm which takes into account the model uncertainties, the disturbances and command signal limitations like robust control. However the resulting controller is complex, involving cost effective hardware. This paper proposes a simple integer-order control scheme using a linear model of the process, based on active disturbance rejection method. By treating the model dynamics as a common disturbance and actively rejecting it, active disturbance rejection control (ADRC) can achieve the desired response. Simulation results are provided to demonstrate the effectiveness of the proposed method.

  15. Characterization of an Actively Controlled Three-Dimensional Turret Wake

    Science.gov (United States)

    Shea, Patrick; Glauser, Mark

    2012-11-01

    Three-dimensional turrets are commonly used for housing optical systems on airborne platforms. As bluff bodies, these geometries generate highly turbulent wakes that decrease the performance of the optical systems and the aircraft. The current experimental study looked to use dynamic suction in both open and closed-loop control configurations to actively control the turret wake. The flow field was characterized using dynamic pressure and stereoscopic PIV measurements in the wake of the turret. Results showed that the suction system was able to manipulate the wake region of the turret and could alter not only the spatial structure of the wake, but also the temporal behavior of the wake flow field. Closed-loop, feedback control techniques were used to determine a more optimal control input for the flow control. Similar control effects were seen for both the steady open-loop control case and the closed-loop feedback control configuration with a 45% reduction in the suction levels when comparing the closed-loop to the open-loop case. These results provide unique information regarding the development of the baseline three-dimensional wake and the wake with three different active flow control configurations.

  16. Actively controlled shaft seals for aerospace applications

    Science.gov (United States)

    Salant, Richard F.

    1995-07-01

    This study experimentally investigates an actively controlled mechanical seal for aerospace applications. The seal of interest is a gas seal, which is considerably more compact than previous actively controlled mechanical seals that were developed for industrial use. In a mechanical seal, the radial convergence of the seal interface has a primary effect on the film thickness. Active control of the film thickness is established by controlling the radial convergence of the seal interface with a piezoelectric actuator. An actively controlled mechanical seal was initially designed and evaluated using a mathematical model. Based on these results, a seal was fabricated and tested under laboratory conditions. The seal was tested with both helium and air, at rotational speeds up to 3770 rad/sec, and at sealed pressures as high as 1.48 x 10(exp 6) Pa. The seal was operated with both manual control and with a closed-loop control system that used either the leakage rate or face temperature as the feedback. The output of the controller was the voltage applied to the piezoelectric actuator. The seal operated successfully for both short term tests (less than one hour) and for longer term tests (four hours) with a closed-loop control system. The leakage rates were typically 5-15 slm (standard liters per minute), and the face temperatures were generally maintained below 100C. When leakage rate was used as the feedback signal, the setpoint leakage rate was typically maintained within 1 slm. However, larger deviations occurred during sudden changes in sealed pressure. When face temperature was used as the feedback signal, the setpoint face temperature was generally maintained within 3 C, with larger deviations occurring when the sealed pressure changes suddenly. the experimental results were compared to the predictions from the mathematical model. The model was successful in predicting the trends in leakage rate that occurred as the balance ratio and sealed pressure changed

  17. Heterodyne interferometric technique for displacement control at the nanometric scale

    Science.gov (United States)

    Topcu, Suat; Chassagne, Luc; Haddad, Darine; Alayli, Yasser; Juncar, Patrick

    2003-11-01

    We propose a method of displacement control that addresses the measurement requirements of the nanotechnology community and provide a traceability to the definition of the mèter at the nanometric scale. The method is based on the use of both a heterodyne Michelson's interferometer and a homemade high frequency electronic circuit. The system so established allows us to control the displacement of a translation stage with a known step of 4.945 nm. Intrinsic relative uncertainty on the step value is 1.6×10-9. Controls of the period of repetition of these steps with a high-stability quartz oscillator permits to impose an uniform speed to the translation stage with the same accuracy. This property will be used for the watt balance project of the Bureau National de Métrologie of France.

  18. 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.

  19. 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...

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

    International Nuclear Information System (INIS)

    Rajurkar, N.S.; Pardeshi, B.M.

    1997-01-01

    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)

  1. Active Noise Control for Dishwasher noise

    Science.gov (United States)

    Lee, Nokhaeng; Park, Youngjin

    2016-09-01

    The dishwasher is a useful home appliance and continually used for automatically washing dishes. It's commonly placed in the kitchen with built-in style for practicality and better use of space. In this environment, people are easily exposed to dishwasher noise, so it is an important issue for the consumers, especially for the people living in open and narrow space. Recently, the sound power levels of the noise are about 40 - 50 dBA. It could be achieved by removal of noise sources and passive means of insulating acoustical path. For more reduction, such a quiet mode with the lower speed of cycle has been introduced, but this deteriorates the washing capacity. Under this background, we propose active noise control for dishwasher noise. It is observed that the noise is propagating mainly from the lower part of the front side. Control speakers are placed in the part for the collocation. Observation part of estimating sound field distribution and control part of generating the anti-noise are designed for active noise control. Simulation result shows proposed active noise control scheme could have a potential application for dishwasher noise reduction.

  2. New sanitation techniques for controlling tephritid fruit flies (Diptera ...

    African Journals Online (AJOL)

    New approaches to sanitation in a cropping system susceptible to tephritid fruit flies (Diptera tephritidae) in Hawaii have been investigated. Six trials were conducted in tent-like structures to demonstrate that melon fly larvae (Bacrocera cucurbitae, Coquillett) are not reliably controlled by malathion sprayed on the surface of ...

  3. An alternative technique in the control of massive presacral rectal ...

    African Journals Online (AJOL)

    ... use of all technical possibilities such as packing, ligation, and hemostatic agents. Bleeding control was provided by GORE‑TEX® graft. We conclude that fıxatıon of GORE‑TEX® aortic patch should be kept in mind for uncontrolled massive presacral bleeding. Keywords: GORE‑TEX® graft, presacral bleeding, rectal cancer ...

  4. Adaptive and robust active vibration control methodology and tests

    CERN Document Server

    Landau, Ioan Doré; Castellanos-Silva, Abraham; Constantinescu, Aurelian

    2017-01-01

    This book approaches the design of active vibration control systems from the perspective of today’s ideas of computer control. It formulates the various design problems encountered in the active management of vibration as control problems and searches for the most appropriate tools to solve them. The experimental validation of the solutions proposed on relevant tests benches is also addressed. To promote the widespread acceptance of these techniques, the presentation eliminates unnecessary theoretical developments (which can be found elsewhere) and focuses on algorithms and their use. The solutions proposed cannot be fully understood and creatively exploited without a clear understanding of the basic concepts and methods, so these are considered in depth. The focus is on enhancing motivations, algorithm presentation and experimental evaluation. MATLAB®routines, Simulink® diagrams and bench-test data are available for download and encourage easy assimilation of the experimental and exemplary material. Thre...

  5. Quality control of the activity meter

    International Nuclear Information System (INIS)

    Rodrigues, Marlon da Silva Brandão; Sá, Lídia Vasconcelos de

    2017-01-01

    Objective: To carry out a comparative analysis of national and international standards regarding the quality control of the activity meter used in Nuclear Medicine Services in Brazil. Material and methods: Quality control protocols from the International Atomic Energy Agency (IAEA), American Association of Physicists in Medicine (AAPM) and International Electrotechnical Commission (IEC) were pointed out and compared with requirements from both regulatory Brazilian agencies, National Surveillance Agency (ANVISA) and National Nuclear Energy Commission (CNEN). Results: The daily routine tests recommended by the regulatory agencies do not have significant differences; in contrast the tests with higher periodicities like (accuracy, linearity and precision) have differences discrepant. Conclusion: In view of the comparative analysis carried out, it is suggested that the national recommendations for the quality control tests of the activity meter should be checked and evaluated, with emphasis on the semiannual and annual periodicity tests. (author)

  6. Evaluation and qualification of novel control techniques with safety requirements

    International Nuclear Information System (INIS)

    Gossner, S.; Wach, D.

    1985-01-01

    The paper discusses the questions related to the assessment and qualification of new I and C-systems. The tasks of nuclear power plant I and Cs as well as the efficiency of the new techniques are reflected. Problems with application of new I and Cs and the state of application in Germany and abroad are addressed. Starting from the essential differencies between conventional and new I and C-systems it is evaluated, if and in which way existing safety requirements can be met and to what extent new requirements need to be formulated. An overall concept has to be developed comprising the definition of graded requirement profiles for design and qualification. Associated qualification procedures and tools have to be adapted, developed and tuned upon each other. (orig./HP) [de

  7. Improving Accuracy of Processing Through Active Control

    Directory of Open Access Journals (Sweden)

    N. N. Barbashov

    2016-01-01

    Full Text Available An important task of modern mathematical statistics with its methods based on the theory of probability is a scientific estimate of measurement results. There are certain costs under control, and under ineffective control when a customer has got defective products these costs are significantly higher because of parts recall.When machining the parts, under the influence of errors a range scatter of part dimensions is offset towards the tolerance limit. To improve a processing accuracy and avoid defective products involves reducing components of error in machining, i.e. to improve the accuracy of machine and tool, tool life, rigidity of the system, accuracy of the adjustment. In a given time it is also necessary to adapt machine.To improve an accuracy and a machining rate there, currently  become extensively popular various the in-process gaging devices and controlled machining that uses adaptive control systems for the process monitoring. Improving the accuracy in this case is compensation of a majority of technological errors. The in-cycle measuring sensors (sensors of active control allow processing accuracy improvement by one or two quality and provide a capability for simultaneous operation of several machines.Efficient use of in-cycle measuring sensors requires development of methods to control the accuracy through providing the appropriate adjustments. Methods based on the moving average, appear to be the most promising for accuracy control since they include data on the change in some last measured values of the parameter under control.

  8. A novel technique for active vibration control, based on optimal ...

    Indian Academy of Sciences (India)

    BEHROUZ KHEIRI SARABI

    2017-07-11

    Jul 11, 2017 ... damper system is considered as a test system. The mathematical model of the ... finite actuator dynamics for flexible structures to over- come instability. ... These equations can be converted into a state-space for- mat by taking.

  9. Plasma control techniques of the ASDEX feedback system

    International Nuclear Information System (INIS)

    Schneider, F.

    1981-01-01

    In the ASDEX tokamak the shots are exactly preprogrammed and most of the disturbances are reproducible. So a computer can learn from one shot how to correct the next one. With this sort of disturbance feedforward one can also introduce a 'negative delay' in the program to compensate even fast and strong disturbances withous unwanted overswing or oscillations. The feedforward in conjunction with feedback control allows production of a magnetically limited plasma from the very beginning without any wall or limiter contact. This is a reason why in ASDEX the loop voltage on breakdown can be as low as 5 V/sup 2/. The plasma column can be controlled in the vacuum vessel even after disruptions have occurred

  10. Advanced Instrumentation and control techniques for nuclear power plants

    International Nuclear Information System (INIS)

    Mori, Nobuyuki; Makino, Maomi; Naito, Norio

    1992-01-01

    Toshiba has been promoting the development of an advanced instrumentation and control system for nuclear power plants to fulfill the requirements for increased reliability, improved functionality and maintainability, and more competitive economic performance. This system integrates state-of-the-art technologies such as those for the latest man-machine interface, digital processing, optical multiplexing signal transmission, human engineering, and artificial intelligence. Such development has been systematically accomplished based on a schematic view of integrated digital control and instrumentation systems, and the development of whole systems has now been completed. This paper describes the purpose, design philosophy, and contents of newly developed systems, then considers the future trends of advanced man-machine systems. (author)

  11. Technique for forming ITO films with a controlled refractive index

    Energy Technology Data Exchange (ETDEWEB)

    Markov, L. K., E-mail: l.markov@mail.ioffe.ru; Smirnova, I. P.; Pavluchenko, A. S.; Kukushkin, M. V.; Zakheim, D. A.; Pavlov, S. I. [Russian Academy of Sciences, Ioffe Physical–Technical Institute (Russian Federation)

    2016-07-15

    A new method for fabricating transparent conducting coatings based on indium-tin oxide (ITO) with a controlled refractive index is proposed. This method implies the successive deposition of material by electron-beam evaporation and magnetron sputtering. Sputtered coatings with different densities (and, correspondingly, different refractive indices) can be obtained by varying the ratio of the mass fractions of material deposited by different methods. As an example, films with effective refractive indices of 1.2, 1.4, and 1.7 in the wavelength range of 440–460 nm are fabricated. Two-layer ITO coatings with controlled refractive indices of the layers are also formed by the proposed method. Thus, multilayer transparent conducting coatings with desired optical parameters can be produced.

  12. A new approach to PWR power control using intelligent techniques

    International Nuclear Information System (INIS)

    Boroushaki, M.; Ghofrani, M.B.; Lucas, C.; Yazdanpanah, M.J.; Sadati, N.

    2004-01-01

    Improved load following capability is one of the main technical performances of advanced PWR(APWR). Controlling the nuclear reactor core during load following operation encounters some difficulties. These difficulties mainly arise from nuclear reactor core limitations in local power peaking, while the core is subject to large and sharp variation of local power density during transients. Axial offset (A.O) is the parameter usually used to represent of core power peaking, in form of a practical parameter. This paper, proposes a new intelligent approach to A.o control of PWR nuclear reactors core during load following operation. This method uses a neural network model of the core to predict the dynamic behavior of the core and a fuzzy critic based on the operator knowledge and experience for the purpose of decision-making during load following operations. Simulation results show that this method can use optimum control rod groups maneuver with variable overlapping and may improve the reactor load following capability

  13. Spherical crystallization: A technique use to reform solubility and flow property of active pharmaceutical ingredients.

    Science.gov (United States)

    Chatterjee, Arindam; Gupta, Madan Mohan; Srivastava, Birendra

    2017-01-01

    Tablets have been choice of manufacturers over the years due to their comparatively low cost of manufacturing, packaging, shipping, and ease of administration; also have better stability and can be considered virtually tamper proof. A major challenge in formulation development of the tablets extends from lower solubility of the active agent to the elaborated manufacturing procedures for obtaining a compressible granular material. Moreover, the validation and documentation increases, as the numbers of steps increases for an industrially acceptable granulation process. Spherical crystallization (SC) is a promising technique, which encompass the crystallization, agglomeration, and spheronization phenomenon in a single step. Initially, two methods, spherical agglomeration, and emulsion solvent diffusion, were suggested to get a desired result. Later on, the introduction of modified methods such as crystallo-co-agglomeration, ammonia diffusion system, and neutralization techniques overcame the limitations of the older techniques. Under controlled conditions such as solvent composition, mixing rate and temperature, spherical dense agglomerates cluster from particles. Application of the SC technique includes production of compacted spherical particles of drug having improved uniformity in shape and size of particles, good bulk density, better flow properties as well as better solubility so SC when used on commercial scale will bring down the production costs of pharmaceutical tablet and will increase revenue for the pharmaceutical industries in the competitive market. This review summarizes the technologies available for SC and also suggests the parameters for evaluation of a viable product.

  14. 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

  15. 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.

  16. Nuclear activation techniques in the life sciences, 1978

    International Nuclear Information System (INIS)

    Parr, R.M.; Ryabukhin, Yu.S.

    1978-01-01

    A brief summary of the symposium is presented, pointing out the main achievements in the use of activation analysis for elemental analysis of biological materials. Some of the individual papers presented at the meeting are mentioned

  17. BWR startup and shutdown activity transport control

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, S.E., E-mail: sgarcia@epri.com [Electric Power Research Inst. (EPRI), Palo Alto, California (United States); Giannelli, J.F.; Jarvis, A.J., E-mail: jgiannelli@finetech.com, E-mail: ajarvis@finetech.com [Finetech, Inc., Parsippany, New Jersey (United States)

    2010-07-01

    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 {sup o

  18. 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.

  19. New technique for determining unavailability of computer controlled safety systems

    International Nuclear Information System (INIS)

    Fryer, M.O.; Bruske, S.Z.

    1984-04-01

    The availability of a safety system for a fusion reactor is determined. A fusion reactor processes tritium and requires an Emergency Tritium Cleanup (ETC) system for accidental tritium releases. The ETC is computer controlled and because of its complexity, is an excellent candidate for this analysis. The ETC system unavailability, for preliminary untested software, is calculated based on different assumptions about operator response. These assumptions are: (a) the operator shuts down the system after the first indication of plant failure; (b) the operator shuts down the system after following optimized failure verification procedures; or (c) the operator is taken out of the decision process, and the computer uses the optimized failure verification procedures

  20. Thin layer activation technique applied to the measurement of wear

    Energy Technology Data Exchange (ETDEWEB)

    Humphries, P [UKAEA Research Group, Harwell. Atomic Energy Research Establishment

    1978-01-01

    A thin layer of radioactive atoms is produced in the material by bombardment with charged particles, and as the material is worn away the total activity level is monitored. If the activity to depth relationship is then known the amount of material worn away can be determined. By a selective choice of the charged particle species and energy the depth of the active layer, its natural decay rate, and the energy of the emitted radiation can be pre-determined. The Harwell Tandem Electrostatic Generator has been found very suitable for the work. The total activity level can be made as little or as large as required, but a level around 5 to 10 microcuries is usually found to be adequate, and the active layer usually has a depth of 50 to 300 ..mu..m. The activated area can be from < 1 mm/sup 2/ to 4 cm/sup 2/. Particular reference is made to the production of /sup 56/Co in Fe. Experimental arrangements for the irradiation of components are described. Some practical applications undertaken by Harwell for industry are briefly mentioned, including wear of diesel engine valve seatings and fuel injection equipment, engine testing of lubricants, surface loss of rails and railway wheels, wear of gears, wear of graphite bearing materials, and corrosion and erosion of materials. 4 references.

  1. Pulsed neutron generator for mass flow measurement using the pulsed neutron activation technique

    International Nuclear Information System (INIS)

    Rochau, G.E.; Hornsby, D.R.; Mareda, J.F.; Riggan, W.C.

    1980-01-01

    A high-output, transportable neutron generator has been developed to measure mass flow velocities in reactor safety tests using the Pulsed Neutron Activation (PNA) Technique. The PNA generator produces >10 10 14 MeV D-T neutrons in a 1.2 millisecond pulse. The Millisecond Pulse (MSP) Neutron Tube, developed for this application, has an expected operational life of 1000 pulses, and it limits the generator pulse repetition rate to 12 pulses/minute. A semiconductor neutron detector is included in the generator package to monitor the neutron output. The control unit, which can be operated manually or remotely, also contains a digital display with a BCD output for the neutron monitor information. The digital logic of the unit controls the safety interlocks and rejects transient signals which could accidently fire the generator

  2. Exploring machine-learning-based control plane intrusion detection techniques in software defined optical networks

    Science.gov (United States)

    Zhang, Huibin; Wang, Yuqiao; Chen, Haoran; Zhao, Yongli; Zhang, Jie

    2017-12-01

    In software defined optical networks (SDON), the centralized control plane may encounter numerous intrusion threatens which compromise the security level of provisioned services. In this paper, the issue of control plane security is studied and two machine-learning-based control plane intrusion detection techniques are proposed for SDON with properly selected features such as bandwidth, route length, etc. We validate the feasibility and efficiency of the proposed techniques by simulations. Results show an accuracy of 83% for intrusion detection can be achieved with the proposed machine-learning-based control plane intrusion detection techniques.

  3. Enhanced Quality Control in Pharmaceutical Applications by Combining Raman Spectroscopy and Machine Learning Techniques

    Science.gov (United States)

    Martinez, J. C.; Guzmán-Sepúlveda, J. R.; Bolañoz Evia, G. R.; Córdova, T.; Guzmán-Cabrera, R.

    2018-06-01

    In this work, we applied machine learning techniques to Raman spectra for the characterization and classification of manufactured pharmaceutical products. Our measurements were taken with commercial equipment, for accurate assessment of variations with respect to one calibrated control sample. Unlike the typical use of Raman spectroscopy in pharmaceutical applications, in our approach the principal components of the Raman spectrum are used concurrently as attributes in machine learning algorithms. This permits an efficient comparison and classification of the spectra measured from the samples under study. This also allows for accurate quality control as all relevant spectral components are considered simultaneously. We demonstrate our approach with respect to the specific case of acetaminophen, which is one of the most widely used analgesics in the market. In the experiments, commercial samples from thirteen different laboratories were analyzed and compared against a control sample. The raw data were analyzed based on an arithmetic difference between the nominal active substance and the measured values in each commercial sample. The principal component analysis was applied to the data for quantitative verification (i.e., without considering the actual concentration of the active substance) of the difference in the calibrated sample. Our results show that by following this approach adulterations in pharmaceutical compositions can be clearly identified and accurately quantified.

  4. Nuclear techniques for the study of environmental pollution and control: experience and facilities at PINSTECH

    International Nuclear Information System (INIS)

    Rajput, M.U.; Butt, N.M.

    2001-01-01

    Environmental pollution is a worldwide problem. Developed countries have already gone in the clutches of pollution. Now the rapid industrialization and modernization process has also started in the developing countries. This is posing a serious threat to their own environment. One of the important factors in the pollution control measures is to investigate the levels of environmental pollution, from time to time, by effective and reliable methods. Nuclear techniques due to their high sensitivities play an important role in this regard. These techniques have the potential to determine the concentration of pollutants in trace level quantities (ppm and ppb) and for locating the possible pollution sources such as power plants, refineries, municipal waste, industries etc. Pakistan Institute of Nuclear Science and Technology (PINSTECH) has qualified and experienced scientists and has nearly all the major nuclear facilities that are needed for environmental research such as mass spectrometry, tracer techniques, neutron activation analysis (NAA), X-ray fluorescence spectrometry (XRFS), atomic absorption spectrometry (AAS), atomic emission spectrometry (AES), inductively coupled plasma-optical emission spectrometry (ICP-OES) etc. This paper discusses the importance of environmental pollution with a particular reference to the pollution aspects in Pakistan and the associated environmental research experience based on nuclear methods available at PINSTECH. 308 refs. (author)

  5. Wind Turbine Rotors with Active Vibration Control

    DEFF Research Database (Denmark)

    Svendsen, Martin Nymann

    that the basic modes of a wind turbine blade can be effectively addressed by an in-blade ‘active strut’ actuator mechanism. The importance of accounting for background mode flexibility is demonstrated. Also, it is shown that it is generally possible to address multiple beam modes with multiple controllers, given...... in the targeted modes and the observed spill-over to other modes is very limited and generally stabilizing. It is shown that physical controller positioning for reduced background noise is important to the calibration. By simulation of the rotor response to both simple initial conditions and a stochastic wind......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...

  6. Developing Sterile Insect Technique (SIT) as a tool Mosquito Control Districts can use for integrated Aedes aegypti control

    Science.gov (United States)

    New tools are clearly needed for integrated mosquito management of Ae. aegypti. We describe the sterile insect technique (SIT) that we are developing as a method to control Ae. aegypti by partnering with two prominent Florida mosquito control districts (MCD) and the FAO/IAEA Insect Pest Control Sub...

  7. HPLC-MS technique for radiopharmaceuticals research and control

    Energy Technology Data Exchange (ETDEWEB)

    Macasek, F; Bruder, P [Department of Nuclear Chemistry, Faculty of Natural Sciences, Comenius University, Bratislava (Slovakia); Buriova, E [Cyclotron Centre of the Slovak Republic, Slovak Office of Standards, Metrology and Testing, Bratislava (Slovakia)

    2002-03-01

    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-[{sup 18}F]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.NH{sub 4}{sup +}, fdg.Na{sup +} and (fdg{sub 2}-CH{sub 3}O).Na{sup +} (m/z = 200, 205 and 344); (ii) negative ions: fdg.Cl{sup -} and fdg.HCOO{sup -} (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/[{sup 19}F]FDG, sorbitol/[{sup 19}F]FDG, xylitol, and other compounds. However, radiometric analysis of expired samples of [{sup 18}F]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

  8. HPLC-MS technique for radiopharmaceuticals research and control

    International Nuclear Information System (INIS)

    Macasek, F.; Bruder, P.; Buriova, E.

    2002-01-01

    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-[ 18 F]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.NH 4 + , fdg.Na + and (fdg 2 -CH 3 O).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/[ 19 F]FDG, sorbitol/[ 19 F]FDG, xylitol, and other compounds. However, radiometric analysis of expired samples of [ 18 F]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

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

    Science.gov (United States)

    Leishman, Timothy W.

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

  10. Air pollution studies in Tianjing city using neutron activation analysis techniques

    International Nuclear Information System (INIS)

    Ni Bangfa; Tian Weizhi; Nie Nuiling; Wang Pingsheng

    1999-01-01

    Two sites of airborne sampling from industrial and residential areas were made in Tianjing city during February and June using PM-10 sampler and analyzed by NAA techniques; Comparison of air pollution between urban and rural area in Tianjing city was made using neutron activation analysis techniques and some other data analyzing techniques. (author)

  11. Justification of rational parameters of briquetting using mechanic activation techniques

    Science.gov (United States)

    Nikolaeva, L. A.; Burenina, O. N.

    2017-12-01

    The paper illustrates results of development of technology and compositions of briquetting substandard lignite waste with the use of tar as a binder, modified with mechanically activated organic-mineral fillers. The influence of highly disperse additives and technological briquetting regimes on the structure formation and the qualitative characteristics of fuel brown coal briquettes is considered.

  12. A randomized controlled trial of nasolaryngoscopy training techniques.

    Science.gov (United States)

    Smith, Matthew E; Leung, Billy C; Sharma, Rishi; Nazeer, Sammar; McFerran, Don J

    2014-09-01

    Flexible nasolaryngoscopy is an essential skill for otolaryngology trainees to develop, but there is a lack of standardized training for this procedure. The aim of this study was to assess whether using training on a realistic human mannequin together with structured video feedback improved trainees' performance at flexible nasolaryngoscopy. Three-armed, single-blinded, randomized controlled study. Thirty-six junior doctors and final-year medical students were randomly allocated to one of three groups. All received a lecture and video presentation on flexible nasolaryngoscopy. One group received additional tuition using a training mannequin. The last group received mannequin training and feedback on their performance using a video recording. The trainees then undertook flexible nasolaryngoscopy on volunteers with these endoscopies recorded. Blinded observers scored the trainees on a range of objective and subjective measures. The volunteers who were also blinded to the candidates' training scored the comfort of the procedure. Adding mannequin training showed a trend toward improvement of performance but did not reach statistical significance. Mannequin training together with video feedback produced significant performance improvement in patient comfort (P = .0065), time to reach the vocal folds (P = .017), and global ability (P = .0006). Inter-rater reliability was excellent with P training using an anatomically correct model of the upper airway together with formalized video-assisted feedback on that training is a simple and effective way to improve endoscopy skills prior to starting flexible nasolaryngoscopy on patients. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

  13. 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.

  14. 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...... with the result that the detection and isolation time can be long. In this paper it will be shown, that this problem can be handled by using a modification of the feedback controller. By applying the YJBK-parameterization (after Youla, Jabr, Bongiorno and Kucera) for the controller, it is possible to modify...... 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....

  15. Behaviour change techniques in physical activity interventions for men with prostate cancer: A systematic review.

    Science.gov (United States)

    Hallward, Laura; Patel, Nisha; Duncan, Lindsay R

    2018-02-01

    Physical activity interventions can improve prostate cancer survivors' health. Determining the behaviour change techniques used in physical activity interventions can help elucidate the mechanisms by which an intervention successfully changes behaviour. The purpose of this systematic review was to identify and evaluate behaviour change techniques in physical activity interventions for prostate cancer survivors. A total of 7 databases were searched and 15 studies were retained. The studies included a mean 6.87 behaviour change techniques (range = 3-10), and similar behaviour change techniques were implemented in all studies. Consideration of how behaviour change techniques are implemented may help identify how behaviour change techniques enhance physical activity interventions for prostate cancer survivors.

  16. Neutron activation: an invaluable technique for teaching applied radiation

    International Nuclear Information System (INIS)

    Trainer, Matthew

    2002-01-01

    This experiment introduces students to the important method of neutron activation. A sample of aluminium was irradiated with neutrons from an isotropic 241 Am-Be source. Using γ-ray spectroscopy, two radionuclide products were identified as 27 Mg and 28 Al. Applying a cadmium cut-off filter and an optimum irradiation time of 45 min, the half-life of 27 Mg was determined as 9.46±0.50 min. The half-life of the 28 Al radionuclide was determined as 2.28±0.10 min using a polythene moderator and an optimum irradiation time of 10 min. (author)

  17. Lithium carbonate tablets. Preparation techniques influence over active ingredient liberation

    International Nuclear Information System (INIS)

    Bueno, J.H.F.; Oliveira, A.G. de; Toledo Salgado, P.E. de

    1989-01-01

    Lithium carbonate tablets, prepared using wet and dry granulation, were assessed in vitro so as to determine the active ingredient dissolution. In this study, standardized formulations were used and developed with usual adjuvants (lactose - maize starch). Parallel to the dissolution testing. The influence of the preparation process over some physical characteristics (hardness, friability and disintegration) was also analysed. Although a better performance was observed of tables prepared using dry granulation, the authors concluded that the wet process is more suitable in preparing tables with the mentioned drug. (author)

  18. Longitudinal vortex control - Techniques and applications (The 32nd Lanchester Lecture)

    Science.gov (United States)

    Bushnell, D. M.

    1992-01-01

    A summary is presented of vortex control applications and current techniques for the control of longitudinal vortices produced by bodies, leading edges, tips and intersections. Vortex control has up till now been performed by many approaches in an empirical fashion, assisted by the essentially inviscid nature of much of longitudinal vortex behavior. Attention is given to Reynolds number sensitivities, vortex breakdown and interactions, vortex control on highly swept wings, and vortex control in juncture flows.

  19. Contamination control research activities for space optics in JAXA RANDD

    Science.gov (United States)

    Kimoto, Y.

    2017-11-01

    Contamination control research activities for space optics projects in JAXA R&D are described. More accurate contamination control techniques are requested because of intensified recent science mission requirements. One approach to control the contamination effects is analysis by software. JAXA has been developing a contamination analytical tool "J-SPICE" (Japanese Spacecraft Induced Contamination analysis software) as well as experiment facilities to improve the J-SPICE. A reflection model in J-SPICE has been experimentally verified and outgassing model data has been acquired by a facility. JAXA has developed a facility which could determine the influence of the contamination at a specific wavelength by combining a vacuum chamber with an I-R spectrometer and performed an experiment to inspect the effect of baking. Space material exposure experiment results reveal the actual thickness of the contamination layer in ISS orbit.

  20. Wear studies of engine components using neutron activation techniques

    International Nuclear Information System (INIS)

    Banados Perez, H.E.; Carvalho, G.; Daltro, T.F.L.

    1984-01-01

    The results obtained in a series of tests for determining the wearing rate of some diesel engine components are reported. The pieces investigated were the needles of fuel injection nozzles, that were previously irradiated with a 10 13 nv in the IEA-R1 nuclear reactor, and the wearing rate was established for different types of fuels. Total wear was calculated by measuring the specific activity of 51 Cr present in the fuel and originated by metal particles worn from the needle. Wear were performed using a device that simulated the actual working conditions of the injection nozzles. The system was run during 350 hours and, along that period, 36 fuel samples of 10 ml each, were collected and analysed for cumulative wear calculation. A metal concentration as low as 10- 6 g in 10 ml of fuel sample could be measured by this method. At present time this procedure is being applied for measuring the wear-rate of other nozzle parts, using localized neutron activation techiques. (Author) [pt

  1. Robust Active Damping Control of LCL Filtered Grid Connected Converter Based Active Disturbance Rejection Control

    DEFF Research Database (Denmark)

    Abdeldjabar, Benrabah; Xu, Dianguo; Wang, Xiongfei

    2016-01-01

    This paper deals with the problem of LCL filter resonance in grid connected inverter control. The system equations are reformulated to allow the application of the active disturbance rejection control (ADRC). The resonance, assumed unknown, is treated as a disturbance, then estimated and mitigated...

  2. 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.

  3. Cold War Arms Control Motivations and Techniques - A Guide for the Future?

    National Research Council Canada - National Science Library

    White, Elmer

    1996-01-01

    .... This paper provides a brief historical account of some of the arms control agreements between the U.S. and the Soviet Union, examines their major motivations to enter into negotiations, and illustrates some successful negotiation techniques. The author hypothesizes on the utility of this Cold War arms control experience as a useful guide for arms control in a single superpower world.

  4. Experimental evaluation of optimal Vehicle Dynamic Control based on the State Dependent Riccati Equation technique

    NARCIS (Netherlands)

    Alirezaei, M.; Kanarachos, S.A.; Scheepers, B.T.M.; Maurice, J.P.

    2013-01-01

    Development and experimentally evaluation of an optimal Vehicle Dynamic Control (VDC) strategy based on the State Dependent Riccati Equation (SDRE) control technique is presented. The proposed nonlinear controller is based on a nonlinear vehicle model with nonlinear tire characteristics. A novel

  5. Advanced Control of Active Bearings - Modelling, Design and Experiments

    DEFF Research Database (Denmark)

    Theisen, Lukas Roy Svane

    In all rotating machines relative movements between the stationary parts and the rotating parts imply energy loss and, in many critical cases, vibration problems. This energy loss leads to higher overall energy consumption of the system. Research activities towards the reduction of friction......, the enhancement of damping, the extension of operating range and the minimisation of critical vibrations in machine elements are of fundamental importance. The main component to tackle the energy-loss-related problems is the bearing. The area of design of active bearings, while very promising, is still in its...... the critical speeds. The feedback control law is preferably designed from a simple model, which captures the dominant dynamics of the machine in the frequency range of interest. This thesis offers two main original contributions in the field of active bearings. First, an experimental technique is proposed...

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

    International Nuclear Information System (INIS)

    Warembourg, F.R.

    1975-01-01

    The use of 14 C made it possible to separate root respired CO 2 and microbial CO 2 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 14 CO 2 . Under axenic conditions evolution of 14 CO 2 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 14 CO 2 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 [fr

  7. Monolithic active pixel radiation detector with shielding techniques

    Energy Technology Data Exchange (ETDEWEB)

    Deptuch, Grzegorz W.

    2018-03-20

    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.

  8. 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.

  9. Active control of the Chinese Giant Solar Telescope

    Science.gov (United States)

    Dai, Yichun; Yang, Dehua; Jin, Zhenyu; Liu, Zhong; Qin, Wei

    2014-07-01

    The Chinese Giant Solar Telescope (CGST) is the next generation solar telescope of China with diameter of 8 meter. The unique feature of CGST is that its primary is a ring, which facilitates the polarization detection and thermal control. In its present design and development phase, two primary mirror patterns are considered. For one thing, the primary mirror is expected to construct with mosaic mirror with 24 trapezoidal (or petal) segments, for another thing, a monolithic mirror is also a candidate for its primary mirror. Both of them depend on active control technique to maintain the optical quality of the ring mirror. As a solar telescope, the working conditions of the CGST are quite different from those of the stellar telescopes. To avoid the image deterioration due to the mirror seeing and dome seeing, especially in the case of the concentration of flux in a solar telescope, large aperture solar projects prefer to adopt open telescopes and open domes. In this circumstance, higher wind loads act on the primary mirror directly, which will cause position errors and figure errors of the primary with matters worse than those of the current 10-meter stellar telescopes with dome protect. Therefore, it gives new challenges to the active control capability, telescope structure design, and wind shielding design. In this paper, the study progress of active control of CGST for its mosaic and monolithic mirror are presented, and the wind effects on such two primary mirrors are also investigated.

  10. 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.

  11. Simple robust technique using time delay estimation for the control and synchronization of Lorenz systems

    International Nuclear Information System (INIS)

    Jin, Maolin; Chang, Pyung Hun

    2009-01-01

    This work presents two simple and robust techniques based on time delay estimation for the respective control and synchronization of chaos systems. First, one of these techniques is applied to the control of a chaotic Lorenz system with both matched and mismatched uncertainties. The nonlinearities in the Lorenz system is cancelled by time delay estimation and desired error dynamics is inserted. Second, the other technique is applied to the synchronization of the Lue system and the Lorenz system with uncertainties. The synchronization input consists of three elements that have transparent and clear meanings. Since time delay estimation enables a very effective and efficient cancellation of disturbances and nonlinearities, the techniques turn out to be simple and robust. Numerical simulation results show fast, accurate and robust performance of the proposed techniques, thereby demonstrating their effectiveness for the control and synchronization of Lorenz systems.

  12. Active Control of Long Bridges Using Flaps

    DEFF Research Database (Denmark)

    Hansen, H. I.; Thoft-Christensen, Palle

    The main problem in designing ultra-long span suspension bridges is flutter. A solution to this problem might be to introduce an active flap control system to increase the flutter wind velocity. The investigated flap control system consists of flaps integrated in the bridge girder so each flap...... is the streamlined part of the edge of the girder. Additional aerodynamic derivatives are shown for the flaps and it is shown how methods already developed can be used to estimate the flutter wind velocity for a bridge section with flaps. As an example, the flutter wind velocity is calculated for different flap...... configurations for a bridge section model by using aerodynamic derivatives for a flat plate. The example shows that different flap configurations can either increase or decrease the flutter wind velocity. for optimal flap configurations flutter will not occur....

  13. 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.

  14. Effectiveness of a Treatment Involving Soft Tissue Techniques and/or Neural Mobilization Techniques in the Management of Tension-Type Headache: A Randomized Controlled Trial.

    Science.gov (United States)

    Ferragut-Garcías, Alejandro; Plaza-Manzano, Gustavo; Rodríguez-Blanco, Cleofás; Velasco-Roldán, Olga; Pecos-Martín, Daniel; Oliva-Pascual-Vaca, Jesús; Llabrés-Bennasar, Bartomeu; Oliva-Pascual-Vaca, Ángel

    2017-02-01

    To evaluate the effects of a protocol involving soft tissue techniques and/or neural mobilization techniques in the management of patients with frequent episodic tension-type headache (FETTH) and those with chronic tension-type headache (CTTH). Randomized, double-blind, placebo-controlled before and after trial. Rehabilitation area of the local hospital and a private physiotherapy center. Patients (N=97; 78 women, 19 men) diagnosed with FETTH or CTTH were randomly assigned to groups A, B, C, or D. (A) Placebo superficial massage; (B) soft tissue techniques; (C) neural mobilization techniques; (D) a combination of soft tissue and neural mobilization techniques. The pressure pain threshold (PPT) in the temporal muscles (points 1 and 2) and supraorbital region (point 3), the frequency and maximal intensity of pain crisis, and the score in the Headache Impact Test-6 (HIT-6) were evaluated. All variables were assessed before the intervention, at the end of the intervention, and 15 and 30 days after the intervention. Groups B, C, and D had an increase in PPT and a reduction in frequency, maximal intensity, and HIT-6 values in all time points after the intervention as compared with baseline and group A (P<.001 for all cases). Group D had the highest PPT values and the lowest frequency and HIT-6 values after the intervention. The application of soft tissue and neural mobilization techniques to patients with FETTH or CTTH induces significant changes in PPT, the characteristics of pain crisis, and its effect on activities of daily living as compared with the application of these techniques as isolated interventions. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  15. Backstepping Based Formation Control of Quadrotors with the State Transformation Technique

    Directory of Open Access Journals (Sweden)

    Keun Uk Lee

    2017-11-01

    Full Text Available In this paper, a backstepping-based formation control of quadrotors with the state transformation technique is proposed. First, the dynamics of a quadrotor is derived by using the Newton–Euler formulation. Next, a backstepping-based formation control for quadrotors using a state transformation technique is presented. In the position control, which is the basis of formation control, it is possible to derive the reference attitude angles employing a state transformation technique without the small angle assumption or the simplified dynamics usually used. Stability analysis based on the Lyapunov theorem shows that the proposed formation controller can provide a quadrotor formation error system that is asymptotically stabilized. Finally, we verify the performance of the proposed formation control method through comparison simulations.

  16. Polders as active element of flood control

    International Nuclear Information System (INIS)

    Zilavy, M.

    2004-01-01

    In this presentation author deals with use of the polders as active element of flood control on the example Kysuca River and Podluzianka River (Slovakia). It was concluded that it is necessary: - dense network of rain gauge stations; - network of water level recorders; revision of design process for hydraulic objects - degree of safety; changes in legislation - permission for construction in flood-plains; maintenance of channel capacity; early flood forecasting - forecasting and warning service; river training works and maintenance; design of retention areas; preparation of retention areas prior to flood propagation

  17. Control charts technique - a tool to data analysis for chemical experiments

    International Nuclear Information System (INIS)

    Yadav, M.B.; Venugopal, V.

    1999-01-01

    A procedure using control charts technique has been developed to analyse data of a chemical experiment which was conducted to assign a value to uranium content in Rb 2 U(SO 4 ) 3 . A value of (34.164 ± 0.031)% has been assigned against (34.167 ± 0.042)% already assigned by analysis of variance (ANOVA) technique. These values do not differ significantly. Merits and demerits of the two techniques have been discussed. (author)

  18. Radiochemical separation and their application to neutron activation analysis technique

    International Nuclear Information System (INIS)

    Turel, Z.R.

    2013-01-01

    The present paper discusses the development of some new, rapid and selective method for the radiochemical separation and estimation of elements such as, Co(II) 2-3 , Ir(III) 4 , Au(III) 5 , Pt(IV), Pd(II), Os(IV) 6 , Cu(II), Ag(I), Mo(VI), Ni(II), Zn(II), Cd(II), Hg(II), Cs(I), Sb(III), La(III), Sc(III) etc. using various reagents. Various parameters such as pH, time of equilibrium, effect of anions and cations, effect of reagent etc. has been determined employing tracers of the elements under consideration and will be discussed. The method is made highly selective by the use of appropriate masking agent. The stoichiometry of metal reagent is determined by the substoichiometric method. Some examples of multielemental radiochemical separation methods thus developed which have been applied in determining the elements by radiochemical thermal neutron activation analysis will be presented and discussed. The implications of the results on the reference system will also be accounted. Statistical evaluation with reference to accuracy, precision and sensitivity will also be presented

  19. 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.

  20. Active control of multiple resistive wall modes

    International Nuclear Information System (INIS)

    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.; Partin, P.; Menmuir, S.; Ortolani, S.; Rachlew, E.; Spizzo, S.; Zanca, P.

    2005-01-01

    Active magnetic feedback suppression of resistive wall modes is of common interest for several fusion concepts relying on close conducting walls for stabilization of ideal magnetohydrodynamic (MHD) modes. In the advanced tokamak without plasma rotation the kink mode is not completely stabilized, but rather converted into an unstable resistive wall mode (RWM) with a growth time comparable to the wall magnetic flux penetration time. The reversed field pinch (RFP) is similar to the advanced tokamak in the sense that it uses a conducting wall for kink mode stabilization. Also both configurations are susceptible to resonant field error amplification of marginally stable modes. However, the RFP has a different RWM spectrum and, in general, a range of modes is unstable. Hence, the requirement for simultaneous feedback stabilization of multiple independent RWMs arises for the RFP configuration. Recent experiments on RWM feedback stabilization, performed in the RFP device EXTRAP T2R [1], are presented. The experimental results obtained are the first demonstration of simultaneous feedback control of multiple independent RWMs [2]. Using an array of active magnetic coils, a reproducible suppression of several RWMs is achieved for the duration of the discharge, 3-5 wall times, through feedback action. An array with 64 active saddle coils at 4 poloidal times 16 toroidal positions is used. The important issues of side band generation by the active coil array and the accompanying coupling of different unstable modes through the feedback action are addressed in this study. Open loop control experiments have been carried out to quantitatively study resonant field error amplification. (Author)

  1. Robust Control and Motion Planning for Nonlinear Underactuated Systems Using H infinity Techniques

    National Research Council Canada - National Science Library

    Toussaint, Gregory

    2000-01-01

    This thesis presents new techniques for planning and robustly controlling the motion of nonlinear underactuated vehicles when disturbances are present and only imperfect state measurements are available for feedback...

  2. Consumer and Commercial Products, Group IV: Control Techniques Guidelines in Lieu of Regulations

    Science.gov (United States)

    EPA has determined that control techniques guidelines (CTGs) will be substantially as effective as regulations in reducing volatile organic compound (VOC) emissions in ozone nonattainment areas for certain consumer and commercial product categories.

  3. 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.

  4. CICERO: research in the design of software for control systems using the object oriented techniques

    Energy Technology Data Exchange (ETDEWEB)

    Barillere, R [and others

    1996-12-31

    CICERO is a collaborative project between industrial companies and research institutes to study the use of object-oriented techniques for needs of complex control systems. The CICERO project is realized in the COBRA standard. 19 refs.

  5. Possibilities to employ noise analysis techniques in controlling nuclear power stations

    International Nuclear Information System (INIS)

    Alfonso Pallares, C.; Iglesias Ferrer, R.; Sarabia Molina, I.

    1998-01-01

    This work shows basic requirements the authors think must be complied with by monitoring systems for operational surveillance based on noise analysis techniques that in turn can be employed in the regulatory control

  6. Seismic qualification of nuclear control board by using base isolation technique

    International Nuclear Information System (INIS)

    Koizumi, T.; Tsujiuchi, N.; Fujita, T.

    1987-01-01

    The purpose is to adopt base isolation technique as a new approach for seismic qualification of nuclear control board. Basic concept of base isolation technique is expressed. Two dimensional linear motion mechanism with pre-tensioned coil springs and some dampers are included in the isolation device. Control board is regarded as a lamped mass system with inertia moment. Fundamental movement of this device and control board is calculated as a non-linear response problems. Fundamental analysis and numerical estimation, experimental investigation has been undertaken using an actual size control board. Sufficient agreement was recognized between experimental results and numerical estimation. (orig./HP)

  7. 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 system...... 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....... 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...

  8. [Brief discussion on acupuncture technique "controlling Qihai to regulate blood pressure" proposed by academician SHI Xuemin].

    Science.gov (United States)

    Yu, Liang; Xu, Xifa; Liu, Jian; Fan, Xiaonong

    2017-08-12

    According to Qihai theory, academician SHI Xuemin established the acupuncture technique "controlling Qihai to regulate blood pressure" which focused on Renying (ST 9), and achieved favorable effects in clinical application. In this paper, based on the Qihai theory, from aspects of Yuan qi , Zong qi , Ying qi and Wei qi and relations among qi , blood and veins in TCM, and cardiac output, sympathetic nerve activity and blood vessels in modern medicine, the understanding on hypertension was explained. As a result, both TCM and modern medicine had consistency in the understanding of hypertension, reflecting the scientificity and practicability of this acupuncture technique. Besides, according to Qihai theory and "wind leading to vertigo" theory, academician SHI Xuemin brought forward the key pathogenesis of hypertension was "dysfunction of Qihai ", and the acupoint selected Renying (ST 9), Quchi (LI 11), Hegu (LI 4), Zusanli (ST 36) and Taichong (LR 3). At the same time, the operation specification of each acupoint was mainly discussed, and the references of acupoint selection was explained based on TCM theory and modern clinical research.

  9. 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.

  10. Designing on-line analyzer for coal on belt conveyor using neutron activation technique

    International Nuclear Information System (INIS)

    Rony Djokorayono; Agus Cahyono

    2014-01-01

    Basic design of on-line analyzer for coal on belt conveyor using neutron activation technique has been carried out. Compared with sampling technique, this neutron activation technique has some advantages in term of analysis accuracy and time. The design activities performed include the establishment of design requirements, functional requirements, technical requirements, technical specification, detection sub-system design, data acquisition subsystem design, and operator computer console design. This program will use Nal(Tl) scintillation detector to detect gamma-rays emitted by elements in coal due to neutron activation of a neutron source, "2"5"2Cf (Californium-252). This basic design of on-line analyzer for coal on belt conveyor using neutron activation technique should be followed up with the development of detailed design, prototype construction, and field testing. (author)

  11. Internal control activities in small Turkish companies

    Directory of Open Access Journals (Sweden)

    Ismail Bilgi

    2017-01-01

    Full Text Available The purpose of this paper is to present major outcomes from an empirical study concerning internal control activities in small Turkish companies, as to propose the improvement guidelines. Methods of analysis and synthesis, descriptive statistics, and statistical comparison were used. The collected data was processed with the help of the SPSS software. Тhe study is limited to organizations based in the European part of Turkey. Most of them operate in areas around large cities, such as Istanbul, Edirne, Kırklareli, and Tekirdağ. They employ on average 19-20 people and have a turnover of about TRY 3 million (≈€715,000, https://sdw.ecb.europa.eu on average. The survey concentrates mainly on small family businesses, which have been present on the market for more than ten years, with managers of good education and other characteristics that presuppose availability of internal control systems. The research results were used to compile main points of a SWOT analysis, as a part of the broader effort to help modernizing the internal control system in Turkish small businesses.

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

    International Nuclear Information System (INIS)

    Mansour, M.

    2012-01-01

    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)

  13. Developments in operator assistance techniques for nuclear power plant control and operation

    International Nuclear Information System (INIS)

    Poujol, A.; Papin, B.; Beltranda, G.; Soldermann, R.

    1989-01-01

    This paper describes an approach which has been developed in order to improve nuclear power plants control and monitoring in normal and abnormal situations. These developments take full advantage of the trend towards the computerization of control rooms in industrial continuous processes. This research program consists in a thorough exploration of different information processing techniques, ranking from the rather simple visual synthetization of informations on graphic displays to sophisticated Artificial Intelligence (AI) techniques. These techniques are put into application for the solving of man-machine interface problems in the different domains of plant operation

  14. Preparation of quality control samples for thyroid hormones T3 and T4 in radioimmunoassay techniques

    International Nuclear Information System (INIS)

    Ahmed, F.O.A.

    2006-03-01

    Today, the radioimmunoassay becomes one of the best techniques for quantitative analysis of very low concentration of different substances. RIA is being widely used in medical and research laboratories. To maintain high specificity and accuracy in RIA and other related techniques the quality controls must be introduced. In this dissertation quality control samples for thyroid hormones (Triiodothyronine T3 and Thyroxin T4), using RIA techniques. Ready made chinese T4, T3 RIA kits were used. IAEA statistical package were selected.(Author)

  15. Stable adaptive PI control for permanent magnet synchronous motor drive based on improved JITL technique.

    Science.gov (United States)

    Zheng, Shiqi; Tang, Xiaoqi; Song, Bao; Lu, Shaowu; Ye, Bosheng

    2013-07-01

    In this paper, a stable adaptive PI control strategy based on the improved just-in-time learning (IJITL) technique is proposed for permanent magnet synchronous motor (PMSM) drive. Firstly, the traditional JITL technique is improved. The new IJITL technique has less computational burden and is more suitable for online identification of the PMSM drive system which is highly real-time compared to traditional JITL. In this way, the PMSM drive system is identified by IJITL technique, which provides information to an adaptive PI controller. Secondly, the adaptive PI controller is designed in discrete time domain which is composed of a PI controller and a supervisory controller. The PI controller is capable of automatically online tuning the control gains based on the gradient descent method and the supervisory controller is developed to eliminate the effect of the approximation error introduced by the PI controller upon the system stability in the Lyapunov sense. Finally, experimental results on the PMSM drive system show accurate identification and favorable tracking performance. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  16. Tuning of PID controller using optimization techniques for a MIMO process

    Science.gov (United States)

    Thulasi dharan, S.; Kavyarasan, K.; Bagyaveereswaran, V.

    2017-11-01

    In this paper, two processes were considered one is Quadruple tank process and the other is CSTR (Continuous Stirred Tank Reactor) process. These are majorly used in many industrial applications for various domains, especially, CSTR in chemical plants.At first mathematical model of both the process is to be done followed by linearization of the system due to MIMO process and controllers are the major part to control the whole process to our desired point as per the applications so the tuning of the controller plays a major role among the whole process. For tuning of parameters we use two optimizations techniques like Particle Swarm Optimization, Genetic Algorithm. The above techniques are majorly used in different applications to obtain which gives the best among all, we use these techniques to obtain the best tuned values among many. Finally, we will compare the performance of the each process with both the techniques.

  17. Fabrication of Polymeric Coatings with Controlled Microtopographies Using an Electrospraying Technique.

    Directory of Open Access Journals (Sweden)

    Qiongyu Guo

    Full Text Available Surface topography of medical implants provides an important biophysical cue on guiding cellular functions at the cell-implant interface. However, few techniques are available to produce polymeric coatings with controlled microtopographies onto surgical implants, especially onto implant devices of small dimension and with complex structures such as drug-eluting stents. Therefore, the main objective of this study was to develop a new strategy to fabricate polymeric coatings using an electrospraying technique based on the uniqueness of this technique in that it can be used to produce a mist of charged droplets with a precise control of their shape and dimension. We hypothesized that this technique would allow facile manipulation of coating morphology by controlling the shape and dimension of electrosprayed droplets. More specifically, we employed the electrospraying technique to coat a layer of biodegradable polyurethane with tailored microtopographies onto commercial coronary stents. The topography of such stent coatings was modulated by controlling the ratio of round to stretched droplets or the ratio of round to crumped droplets under high electric field before deposition. The shape of electrosprayed droplets was governed by the stability of these charged droplets right after ejection or during their flight in the air. Using the electrospraying technique, we achieved conformal polymeric coatings with tailored microtopographies onto conductive surgical implants. The approach offers potential for controlling the surface topography of surgical implant devices to modulate their integration with surrounding tissues.

  18. \\mathscr{H}_2 optimal control techniques for resistive wall mode feedback in tokamaks

    Science.gov (United States)

    Clement, Mitchell; Hanson, Jeremy; Bialek, Jim; Navratil, Gerald

    2018-04-01

    DIII-D experiments show that a new, advanced algorithm enables resistive wall mode (RWM) stability control in high performance discharges using external coils. DIII-D can excite strong, locked or nearly locked external kink modes whose rotation frequencies and growth rates are on the order of the magnetic flux diffusion time of the vacuum vessel wall. Experiments have shown that modern control techniques like linear quadratic Gaussian (LQG) control require less current than the proportional controller in use at DIII-D when using control coils external to DIII-D’s vacuum vessel. Experiments were conducted to develop control of a rotating n  =  1 perturbation using an LQG controller derived from VALEN and external coils. Feedback using this LQG algorithm outperformed a proportional gain only controller in these perturbation experiments over a range of frequencies. Results from high βN experiments also show that advanced feedback techniques using external control coils may be as effective as internal control coil feedback using classical control techniques.

  19. Oceanic control of Northeast Pacific hurricane activity at interannual timescales

    International Nuclear Information System (INIS)

    Balaguru, Karthik; Ruby Leung, L; Yoon, Jin-ho

    2013-01-01

    Sea surface temperature (SST) is not the only oceanic parameter that can play a key role in the interannual variability of Northeast Pacific hurricane activity. Using several observational data sets and the statistical technique of multiple linear regression analysis, we show that, along with SST, the thermocline depth (TD) plays an important role in hurricane activity at interannual timescales in this basin. Based on the parameter that dominates, the ocean basin can be divided into two sub-regions. In the Southern sub-region, which includes the hurricane main development area, interannual variability of the upper-ocean heat content (OHC) is primarily controlled by TD variations. Consequently, the interannual variability in the hurricane power dissipation index (PDI), which is a measure of the intensity of hurricane activity, is driven by that of the TD. On the other hand, in the Northern sub-region, SST exerts the major control over the OHC variability and, in turn, the PDI. Our study suggests that both SST and TD have a significant influence on the Northeast Pacific hurricane activity at interannual timescales and that their respective roles are more clearly delineated when sub-regions along an approximate north–south demarcation are considered rather than the basin as a whole. (letter)

  20. Synchronization control of cross-strict feedback hyperchaotic system based on cross active backstepping design

    International Nuclear Information System (INIS)

    Wang Jing; Gao Jinfeng; Ma Xikui

    2007-01-01

    This Letter presents a novel cross active backstepping design method for synchronization control of cross-strict feedback hyperchaotic system, in which the ordinary backstepping design is unavailable. The proposed control method, combining backstepping design and active control approach, extends the application of backstepping technique in chaos control. Based on this method, different combinations of controllers can be designed to meet the needs of different applications. The proposed method is applied to achieve chaos synchronization of two identical cross-strict feedback hyperchaotic systems. Also it is used to implement synchronization between cross-strict feedback hyperchaotic system and Roessler hyperchaotic system. Numerical examples illustrate the validity of the control method

  1. Behavior change techniques in top-ranked mobile apps for physical activity.

    Science.gov (United States)

    Conroy, David E; Yang, Chih-Hsiang; Maher, Jaclyn P

    2014-06-01

    Mobile applications (apps) have potential for helping people increase their physical activity, but little is known about the behavior change techniques marketed in these apps. The aim of this study was to characterize the behavior change techniques represented in online descriptions of top-ranked apps for physical activity. Top-ranked apps (n=167) were identified on August 28, 2013, and coded using the Coventry, Aberdeen and London-Revised (CALO-RE) taxonomy of behavior change techniques during the following month. Analyses were conducted during 2013. Most descriptions of apps incorporated fewer than four behavior change techniques. The most common techniques involved providing instruction on how to perform exercises, modeling how to perform exercises, providing feedback on performance, goal-setting for physical activity, and planning social support/change. A latent class analysis revealed the existence of two types of apps, educational and motivational, based on their configurations of behavior change techniques. Behavior change techniques are not widely marketed in contemporary physical activity apps. Based on the available descriptions and functions of the observed techniques in contemporary health behavior theories, people may need multiple apps to initiate and maintain behavior change. This audit provides a starting point for scientists, developers, clinicians, and consumers to evaluate and enhance apps in this market. Copyright © 2014 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  2. A three-dimensional muscle activity imaging technique for assessing pelvic muscle function

    Science.gov (United States)

    Zhang, Yingchun; Wang, Dan; Timm, Gerald W.

    2010-11-01

    A novel multi-channel surface electromyography (EMG)-based three-dimensional muscle activity imaging (MAI) technique has been developed by combining the bioelectrical source reconstruction approach and subject-specific finite element modeling approach. Internal muscle activities are modeled by a current density distribution and estimated from the intra-vaginal surface EMG signals with the aid of a weighted minimum norm estimation algorithm. The MAI technique was employed to minimally invasively reconstruct electrical activity in the pelvic floor muscles and urethral sphincter from multi-channel intra-vaginal surface EMG recordings. A series of computer simulations were conducted to evaluate the performance of the present MAI technique. With appropriate numerical modeling and inverse estimation techniques, we have demonstrated the capability of the MAI technique to accurately reconstruct internal muscle activities from surface EMG recordings. This MAI technique combined with traditional EMG signal analysis techniques is being used to study etiologic factors associated with stress urinary incontinence in women by correlating functional status of muscles characterized from the intra-vaginal surface EMG measurements with the specific pelvic muscle groups that generated these signals. The developed MAI technique described herein holds promise for eliminating the need to place needle electrodes into muscles to obtain accurate EMG recordings in some clinical applications.

  3. A Technique for Controlling Matric Suction on Filter Papers . GroWth ...

    African Journals Online (AJOL)

    'Abstract. Moist filter papers are widely usedfor seed gennination tests but their water confent and matric suction are not usually controlled. A technique for controlling filter paper matric suction is described and usedfor germination studies involving fresh and aged sorghum seed (Sorghummcolor (L) Moench). Filter papers ...

  4. A Technique for Controlling Matric Suction on Filter Papers Used in ...

    African Journals Online (AJOL)

    Moist filter papers are widely usedfor seed gennination tests but their water confent and matric suction are not usually controlled. A technique for controlling filter paper matric suction is described and usedfor germination studies involving fresh and aged sorghum seed (Sorghummcolor (L) Moench). Filter papers wetted to ...

  5. In vitro Seed-dressing Technique for the Control of Seed-borne ...

    African Journals Online (AJOL)

    In vitro Seed-dressing Technique for the Control of Seed-borne Fungi of Rice variety Faro -29. ... Journal of Applied Sciences and Environmental Management ... Fernasan-D, Apron Plus 50 DS and Dithane–M45), and soaking and slurry methods at various concentrations, for the control of seed-borne fungi of rice variety

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

    International Nuclear Information System (INIS)

    2006-01-01

    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

  7. 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 ...

  8. Estimation of low level gross alpha activities in the radioactive effluent using liquid scintillation counting technique

    International Nuclear Information System (INIS)

    Bhade, Sonali P.D.; Johnson, Bella E.; Singh, Sanjay; Babu, D.A.R.

    2012-01-01

    A technique has been developed for simultaneous measurement of gross alpha and gross beta activity concentration in low level liquid effluent samples in presence of higher activity concentrations of tritium. For this purpose, alpha beta discriminating Pulse Shape Analysis Liquid Scintillation Counting (LSC) technique was used. Main advantages of this technique are easy sample preparation, rapid measurement and higher sensitivity. The calibration methodology for Quantulus1220 LSC based on PSA technique using 241 Am and 90 Sr/ 90 Y as alpha and beta standards respectively was described in detail. LSC technique was validated by measuring alpha and beta activity concentrations in test samples with known amount of 241 Am and 90 Sr/ 90 Y activities spiked in distilled water. The results obtained by LSC technique were compared with conventional planchet counting methods such as ZnS(Ag) and end window GM detectors. The gross alpha and gross beta activity concentrations in spiked samples, obtained by LSC technique were found to be within ±5% of the reference values. (author)

  9. Synchronization of uncertain time-varying network based on sliding mode control technique

    Science.gov (United States)

    Lü, Ling; Li, Chengren; Bai, Suyuan; Li, Gang; Rong, Tingting; Gao, Yan; Yan, Zhe

    2017-09-01

    We research synchronization of uncertain time-varying network based on sliding mode control technique. The sliding mode control technique is first modified so that it can be applied to network synchronization. Further, by choosing the appropriate sliding surface, the identification law of uncertain parameter, the adaptive law of the time-varying coupling matrix element and the control input of network are designed, it is sure that the uncertain time-varying network can synchronize effectively the synchronization target. At last, we perform some numerical simulations to demonstrate the effectiveness of the proposed results.

  10. The use of singular value gradients and optimization techniques to design robust controllers for multiloop systems

    Science.gov (United States)

    Newsom, J. R.; Mukhopadhyay, V.

    1983-01-01

    A method for designing robust feedback controllers for multiloop systems is presented. Robustness is characterized in terms of the minimum singular value of the system return difference matrix at the plant input. Analytical gradients of the singular values with respect to design variables in the controller are derived. A cumulative measure of the singular values and their gradients with respect to the design variables is used with a numerical optimization technique to increase the system's robustness. Both unconstrained and constrained optimization techniques are evaluated. Numerical results are presented for a two output drone flight control system.

  11. Sensor Development for Active Flow Control

    Science.gov (United States)

    Kahng, Seun K.; Gorton, Susan A.; Mau, Johnney C.; Soto, Hector L.; Hernandez, Corey D.

    2001-01-01

    Presented are the developmental efforts for MEMS sensors for a closed-loop active flow control in a low-speed wind tunnel evaluation. The MEMS sensors are designed in-house and fabricated out of house, and the shear sensors are a thermal type that are collocated with temperature and pressure sensors on a flexible polyimide sheet, which conforms to surfaces of a simple curvature. A total of 6 sensors are located within a 1.5 by 3 mm area as a cluster with each sensor being 300 pm square. The thickness of this sensor cluster is 75 pm. Outputs from the shear sensors have been compared with respect to those of the Preston tube for evaluation of the sensors on a flat plate. Pressure sensors are the absolute type and have recorded pressure measurements within 0.05 percent of the tunnel ESP pressure sensor readings. The sensors and signal conditioning electronics have been tested on both a flat plate and a ramp in Langley s 15-Inch Low-Turbulence Tunnel. The system configuration and control PC is configured with LabView, where calibration constants are stored for desired compensation and correction. The preliminary test results are presented within.

  12. Model predictive control for a dual active bridge inverter with a floating bridge

    OpenAIRE

    Chowdhury, Shajjad; Wheeler, Patrick W.; Gerada, C.; Patel, Chintan

    2016-01-01

    This paper presents a Model Predictive Control technique applied to a dual active bridge inverter where one of the bridges is floating. The proposed floating bridge topology eliminates the need for isolation transformer in a dual inverter system and therefore reduces the size, weight and losses in the system. To achieve multilevel output voltage waveforms the floating inverter DC link capacitor is charged to the half of the main DC link voltage. A finite-set Model Predictive Control technique...

  13. Fuzzy modeling and control of rotary inverted pendulum system using LQR technique

    International Nuclear Information System (INIS)

    Fairus, M A; Mohamed, Z; Ahmad, M N

    2013-01-01

    Rotary inverted pendulum (RIP) system is a nonlinear, non-minimum phase, unstable and underactuated system. Controlling such system can be a challenge and is considered a benchmark in control theory problem. Prior to designing a controller, equations that represent the behaviour of the RIP system must be developed as accurately as possible without compromising the complexity of the equations. Through Takagi-Sugeno (T-S) fuzzy modeling technique, the nonlinear system model is then transformed into several local linear time-invariant models which are then blended together to reproduce, or approximate, the nonlinear system model within local region. A parallel distributed compensation (PDC) based fuzzy controller using linear quadratic regulator (LQR) technique is designed to control the RIP system. The results show that the designed controller able to balance the RIP system

  14. A Survey of Congestion Control Techniques and Data Link Protocols in Satellite Networks

    OpenAIRE

    Fahmy, Sonia; Jain, Raj; Lu, Fang; Kalyanaraman, Shivkumar

    1998-01-01

    Satellite communication systems are the means of realizing a global broadband integrated services digital network. Due to the statistical nature of the integrated services traffic, the resulting rate fluctuations and burstiness render congestion control a complicated, yet indispensable function. The long propagation delay of the earth-satellite link further imposes severe demands and constraints on the congestion control schemes, as well as the media access control techniques and retransmissi...

  15. 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.

  16. Characterizing Dissolved Organic Matter and Metabolites in an Actively Serpentinizing Ophiolite Using Global Metabolomics Techniques

    Science.gov (United States)

    Seyler, L. M.; Rempfert, K. R.; Kraus, E. A.; Spear, J. R.; Templeton, A. S.; Schrenk, M. O.

    2017-12-01

    Environmental metabolomics is an emerging approach used to study ecosystem properties. Through bioinformatic comparisons to metagenomic data sets, metabolomics can be used to study microbial adaptations and responses to varying environmental conditions. Since the techniques are highly parallel to organic geochemistry approaches, metabolomics can also provide insight into biogeochemical processes. These analyses are a reflection of metabolic potential and intersection with other organisms and environmental components. Here, we used an untargeted metabolomics approach to characterize dissolved organic carbon and aqueous metabolites from groundwater obtained from an actively serpentinizing habitat. Serpentinites are known to support microbial communities that feed off of the products of serpentinization (such as methane and H2 gas), while adapted to harsh environmental conditions such as high pH and low DIC availability. However, the biochemistry of microbial populations that inhabit these environments are understudied and are complicated by overlapping biotic and abiotic processes. The aim of this study was to identify potential sources of carbon in an environment that is depleted of soluble inorganic carbon, and to characterize the flow of metabolites and describe overlapping biogenic and abiogenic processes impacting carbon cycling in serpentinizing rocks. We applied untargeted metabolomics techniques to groundwater taken from a series of wells drilled into the Semail Ophiolite in Oman.. Samples were analyzed via quadrupole time-of-flight liquid chromatography tandem mass spectrometry (QToF-LC/MS/MS). Metabolomes and metagenomic data were imported into Progenesis QI software for statistical analysis and correlation, and metabolic networks constructed using the Genome-Linked Application for Metabolic Maps (GLAMM), a web interface tool. Further multivariate statistical analyses and quality control was performed using EZinfo. Pools of dissolved organic carbon could

  17. Two-phase flow measurements using a photochromic dye activation technique

    International Nuclear Information System (INIS)

    Kawaji, M.

    1998-01-01

    A novel flow visualization method called photochromic dye activation (PDA) technique has been used to investigate flow structures and mechanisms in various two-phase flow regimes. This non-intrusive flow visualization technique utilizes light activation of a photochromic dye material dissolved in a clear liquid and is a molecular tagging technique, requiring no seed particles. It has been used to yield both quantitative and qualitative flow data in the liquid phase in annular flow, slug flow and stratified-wavy flows. (author)

  18. An automatic regulating control system for a graphite moderated reactor using digital techniques

    International Nuclear Information System (INIS)

    Carvalho Goncalves Junior, J. de.

    1989-01-01

    The work propose an automatic regulating control system for a graphite moderated reactor using digital techniques. The system uses a microcomputer to monitor the power and the period, to run the control algorithm, and to generate electronic signals to excite the motor, which moves vertically the control rod banks. A nuclear reactor simulator was developed to test the control system. The simulator consists of a software based on the point kinetic equations and implanted in an analogical computer. The results show that this control system has a good performance and versatility. In addition, the simulator is capable of reproducing with accuracy the behavior of a nuclear reactor. (author)

  19. Speed control of induction motor using fuzzy recursive least squares technique

    Directory of Open Access Journals (Sweden)

    Santiago Sánchez

    2008-12-01

    Full Text Available A simple adaptive controller design is presented in this paper, the control system uses the adaptive fuzzy logic, sliding modes and is trained with the recursive least squares technique. The problem of parameter variation is solved with the adaptive controller; the use of an internal PI regulator produces that the speed control of the induction motor be achieved by the stator currents instead the input voltage. The rotor-flux oriented coordinated system model is used to develop and test the control system.

  20. On-line diagnostic techniques for air-operated control valves based on time series analysis

    International Nuclear Information System (INIS)

    Ito, Kenji; Matsuoka, Yoshinori; Minamikawa, Shigeru; Komatsu, Yasuki; Satoh, Takeshi.

    1996-01-01

    The objective of this research is to study the feasibility of applying on-line diagnostic techniques based on time series analysis to air-operated control valves - numerous valves of the type which are used in PWR plants. Generally the techniques can detect anomalies by failures in the initial stages for which detection is difficult by conventional surveillance of process parameters measured directly. However, the effectiveness of these techniques depends on the system being diagnosed. The difficulties in applying diagnostic techniques to air-operated control valves seem to come from the reduced sensitivity of their response as compared with hydraulic control systems, as well as the need to identify anomalies in low level signals that fluctuate only slightly but continuously. In this research, simulation tests were performed by setting various kinds of failure modes for a test valve with the same specifications as of a valve actually used in the plants. Actual control signals recorded from an operating plant were then used as input signals for simulation. The results of the tests confirmed the feasibility of applying on-line diagnostic techniques based on time series analysis to air-operated control valves. (author)

  1. Randomised controlled trial of Alexander technique lessons, exercise, and massage (ATEAM) for chronic and recurrent back pain: economic evaluation.

    Science.gov (United States)

    Hollinghurst, Sandra; Sharp, Debbie; Ballard, Kathleen; Barnett, Jane; Beattie, Angela; Evans, Maggie; Lewith, George; Middleton, Karen; Oxford, Frances; Webley, Fran; Little, Paul

    2008-12-11

    An economic evaluation of therapeutic massage, exercise, and lessons in the Alexander technique for treating persistent back pain. Cost consequences study and cost effectiveness analysis at 12 month follow-up of a factorial randomised controlled trial. 579 patients with chronic or recurrent low back pain recruited from primary care. Normal care (control), massage, and six or 24 lessons in the Alexander technique. Half of each group were randomised to a prescription for exercise from a doctor plus behavioural counselling from a nurse. Costs to the NHS and to participants. Comparison of costs with Roland-Morris disability score (number of activities impaired by pain), days in pain, and quality adjusted life years (QALYs). Comparison of NHS costs with QALY gain, using incremental cost effectiveness ratios and cost effectiveness acceptability curves. Intervention costs ranged from pound30 for exercise prescription to pound596 for 24 lessons in Alexander technique plus exercise. Cost of health services ranged from pound50 for 24 lessons in Alexander technique to pound124 for exercise. Incremental cost effectiveness analysis of single therapies showed that exercise offered best value ( pound61 per point on disability score, pound9 per additional pain-free day, pound2847 per QALY gain). For two-stage therapy, six lessons in Alexander technique combined with exercise was the best value (additional pound64 per point on disability score, pound43 per additional pain-free day, pound5332 per QALY gain). An exercise prescription and six lessons in Alexander technique alone were both more than 85% likely to be cost effective at values above pound20 000 per QALY, but the Alexander technique performed better than exercise on the full range of outcomes. A combination of six lessons in Alexander technique lessons followed by exercise was the most effective and cost effective option.

  2. Active Detection for Exposing Intelligent Attacks in Control Systems

    Energy Technology Data Exchange (ETDEWEB)

    Weerakkody, Sean [Carnegie Mellon Univ., Pittsburgh, PA (United States); Ozel, Omur [Carnegie Mellon Univ., Pittsburgh, PA (United States); Griffioen, Paul [Carnegie Mellon Univ., Pittsburgh, PA (United States); Sinopoli, Bruno [Carnegie Mellon Univ., Pittsburgh, PA (United States)

    2017-07-01

    In this paper, we consider approaches for detecting integrity attacks carried out by intelligent and resourceful adversaries in control systems. Passive detection techniques are often incorporated to identify malicious behavior. Here, the defender utilizes finely-tuned algorithms to process information and make a binary decision, whether the system is healthy or under attack. We demonstrate that passive detection can be ineffective against adversaries with model knowledge and access to a set of input/output channels. We then propose active detection as a tool to detect attacks. In active detection, the defender leverages degrees of freedom he has in the system to detect the adversary. Specifically, the defender will introduce a physical secret kept hidden from the adversary, which can be utilized to authenticate the dynamics. In this regard, we carefully review two approaches for active detection: physical watermarking at the control input, and a moving target approach for generating system dynamics. We examine practical considerations for implementing these technologies and discuss future research directions.

  3. Suitable activated stable nuclide tracer technique and its applications in biology and medicine

    International Nuclear Information System (INIS)

    Zhang Weicheng

    1989-01-01

    Stable isotopes as tracers in biology and medicine have been more extensively used. Mass spectrometry has been a classic technique in the analysis of stable isotopes because it is very sensitive and precise. Activation analysis has recently been introduced as an analytical tool. Its fast speed and simplicity is a great advantage for handling large batches of samples in isotopic tracer experiments. The combination of enriched stable isotope tracer studies and activation analysis techniques has become an ideal and reliable technique, especially in the fields of biology and medicine. This paper presents a survey of the fundamental principle, the character and the applications in biology and medicine for the suitable activated stable isotope tracer techniques

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

    Energy Technology Data Exchange (ETDEWEB)

    1965-06-01

    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.

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

    International Nuclear Information System (INIS)

    1965-01-01

    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. 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

  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. Improving powerlifters’ technical preparedness at initial training stage using a device for remote control of competitive exercises technique

    Directory of Open Access Journals (Sweden)

    А. Власов

    2016-12-01

    Full Text Available The objective is to improve powerlifters’ technical preparedness at the initial training stage using a device for remote control of the competitive exercises technique. Materials and methods. The study relied on the following methods used: theoretical analysis and collation of data of scientific and methodological literature and internet; pedagogical observation; pedagogical experiment; methods of mathematical statistics. Results. We have designed an algorithmic structure for teaching squats with a barbell on shoulders in powerlifting and a device for remote control of the competitive exercises technique. We used the pedagogical experiment and pedagogical observation of the competitive activity to reveal reliable deviations (p > 0.05 in the number of mistakes made by the athletes of the reference and experimental groups during the competitive activity. The reference group powerlifters made the mistake “no straight angle between the knee and the hip joints when performing the third stage” twelve times, while the experimental group athletes — seven times. Conclusions. The results obtained allow to maintain that the experimental group athletes have more rationally mastered the competitive exercises technique and made fewer mistakes compared to the control group powerlifters. This confirms the effectiveness of the designed algorithmic structure for teaching squats with a barbell on shoulders.

  9. Improving general flexibility with a mind-body approach: a randomized, controlled trial using neuro emotional Technique®.

    Science.gov (United States)

    Jensen, Anne M; Ramasamy, Adaikalavan; Hall, Michael W

    2012-08-01

    General flexibility is a key component of health, well-being, and general physical conditioning. Reduced flexibility has both physical and mental/emotional etiologies and can lead to musculoskeletal injuries and athletic underperformance. Few studies have tested the effectiveness of a mind-body therapy on general flexibility. The aim of this study was to investigate if Neuro Emotional Technique® (NET), a mind-body technique shown to be effective in reducing stress, can also improve general flexibility. The sit-and-reach test (SR) score was used as a measure of general flexibility. Forty-five healthy participants were recruited from the general population and assessed for their initial SR score before being randomly allocated to receive (a) two 20-minute sessions of NET (experimental group); (b) two 20-minute sessions of stretching instruction (active control group); or (c) no intervention or instruction (passive control group). After intervention, the participants were reassessed in a similar manner by the same blind assessor. The participants also answered questions about demographics, usual water and caffeine consumption, and activity level, and they completed an anxiety/mood psychometric preintervention and postintervention. The mean (SD) change in the SR score was +3.1 cm (2.5) in the NET group, +1.2 cm (2.3) in the active control group and +1.0 cm (2.6) in the passive control group. Although all the 3 groups showed some improvement, the improvement in the NET group was statistically significant when compared with that of either the passive controls (p = 0.015) or the active controls (p = 0.021). This study suggests that NET could provide an effective treatment in improving general flexibility. A larger study is required to confirm these findings and also to assess longer term effectiveness of this therapy on general flexibility.

  10. WE-DE-209-02: Active Breathing Control

    Energy Technology Data Exchange (ETDEWEB)

    Comsa, D. [Stronach Regional Cancer Centre (Canada)

    2016-06-15

    Breast radiation therapy is associated with some risk of lung toxicity as well as cardiac toxicity for left-sided cases. Radiation doses to the lung and heart can be reduced by using the deep inspiration breath hold (DIBH) technique, in which the patient is simulated and treated during the deep inspiration phase of the breathing cycle. During DIBH, the heart is usually displaced posteriorly, inferiorly, and to the right, effectively expanding the distance between the heart and the breast/chest wall. As a result, the distance between the medial treatment field border and heart/lung is increased. Also, in a majority of DIBH patients, the air drawn into the thoracic cavity increases the total lung volume. The DIBH was discussed by an AAPM Task Group 10 years ago in the AAPM TG 76 report. However, DIBH is still not the standard of care in many clinics, which may be partially due to challenges associated with its implementation. Therefore, this seccion will focus primarily on how to clinically implement four different DIBH techniques: (1) Active Breathing Control, (2) Spirometric Motion Management, (3) 3D Surface Image-Guided, and (4) Self-held Breath Control with Respiratory Monitoring and Feedback Guidance. Learning Objectives: Describe the physical displacement of the heart and the change in lung volume during DIBH and discuss dosimetric consequences of those changes. Provide an overview of the technical aspects. Describe work flow for patient simulation and treatment. Give an overview of commissioning and routine. Provide practical tips for clinical implementation.

  11. WE-DE-209-02: Active Breathing Control

    International Nuclear Information System (INIS)

    Comsa, D.

    2016-01-01

    Breast radiation therapy is associated with some risk of lung toxicity as well as cardiac toxicity for left-sided cases. Radiation doses to the lung and heart can be reduced by using the deep inspiration breath hold (DIBH) technique, in which the patient is simulated and treated during the deep inspiration phase of the breathing cycle. During DIBH, the heart is usually displaced posteriorly, inferiorly, and to the right, effectively expanding the distance between the heart and the breast/chest wall. As a result, the distance between the medial treatment field border and heart/lung is increased. Also, in a majority of DIBH patients, the air drawn into the thoracic cavity increases the total lung volume. The DIBH was discussed by an AAPM Task Group 10 years ago in the AAPM TG 76 report. However, DIBH is still not the standard of care in many clinics, which may be partially due to challenges associated with its implementation. Therefore, this seccion will focus primarily on how to clinically implement four different DIBH techniques: (1) Active Breathing Control, (2) Spirometric Motion Management, (3) 3D Surface Image-Guided, and (4) Self-held Breath Control with Respiratory Monitoring and Feedback Guidance. Learning Objectives: Describe the physical displacement of the heart and the change in lung volume during DIBH and discuss dosimetric consequences of those changes. Provide an overview of the technical aspects. Describe work flow for patient simulation and treatment. Give an overview of commissioning and routine. Provide practical tips for clinical implementation.

  12. Determination of biologically active phenols and polyphenols in various objects by chromatographic techniques

    International Nuclear Information System (INIS)

    Kochetova, M V; Semenistaya, E N; Larionov, Oleg G; Revina, A A

    2007-01-01

    Chromatographic techniques for determination of biologically active phenols and polyphenols are considered. Various methods for sample preparation and detection are compared. The advantages of high performance liquid chromatography with spectrophotometric detection for determination of antioxidants are demonstrated. Data on determination of biologically active phenols and polyphenols published in the period from 1995 to 2005 are analysed.

  13. Detection of active faults using data fusion techniques : case study, Psachna Island of Evoia, Greece

    NARCIS (Netherlands)

    Gountromichou, Chrysa; Pohl, Christine; Ehlers, Manfred

    2002-01-01

    The identification of active faults (faults potentially capable to trigger an earthquake) is important for a seismically active country like Greece. Remote sensing techniques and GIS analysis were used in order to detect, map and characterize the tectonic structures of Psachna town and the

  14. The Tilburg double blind randomised controlled trial comparing inguinal hernia repair according to Lichtenstein and the transinguinal preperitoneal technique

    Directory of Open Access Journals (Sweden)

    Gerritsen Pieter G

    2009-09-01

    Full Text Available Abstract Background Anterior open treatment of the inguinal hernia with a tension free mesh has reduced the incidence of recurrence and direct postoperative pain. The Lichtenstein procedure rules nowadays as reference technique for hernia treatment. Not recurrences but chronic pain is the main postoperative complication in inguinal hernia repair after Lichtenstein's technique. Preliminary experiences with a soft mesh placed in the preperitoneal space showed good results and less chronic pain. Methods The TULIP is a double-blind randomised controlled trial in which 300 patients will be randomly allocated to anterior inguinal hernia repair according to Lichtenstein or the transinguinal preperitoneal technique with soft mesh. All unilateral primary inguinal hernia patients eligible for operation who meet inclusion criteria will be invited to participate in this trial. The primary endpoint will be direct postoperative- and chronic pain. Secondary endpoints are operation time, postoperative complications, hospital stay, costs, return to daily activities (e.g. work and recurrence. Both groups will be evaluated. Success rate of hernia repair and complications will be measured as safeguard for quality. To demonstrate that inguinal hernia repair according to the transinguinal preperitoneal (TIPP technique reduces postoperative pain to Discussion The TULIP trial is aimed to show a reduction in postoperative chronic pain after anterior hernia repair according to the transinguinal preperitoneal (TIPP technique, compared to Lichtenstein. In our hypothesis the TIPP technique reduces chronic pain compared to Lichtenstein. Trial registration ISRCTN 93798494

  15. Tracer technique for measuring specific activity of 63 Ni, using 4πβ-γ

    International Nuclear Information System (INIS)

    Iwahara, A.

    1979-01-01

    The specific activity of a 6 3 Ni solution has been measured by an efficiency tracer technique using a 4 π β - γ coincidence system. 6 3 Ni was chosen. Because it's a very low energy pure beta emitter. Due to chemical compatibility and beta spectral shapes, 6 0 Co has been chosen as tracer. In the determination of 6 3 Ni, the specific activity. As the efficiency tracer techniques requires a previous knowledge of tracer activity, this has been measured by a conventional 4 π β -γ coincidence method. (author)

  16. Connection between optimal control theory and adiabatic-passage techniques in quantum systems

    Science.gov (United States)

    Assémat, E.; Sugny, D.

    2012-08-01

    This work explores the relationship between optimal control theory and adiabatic passage techniques in quantum systems. The study is based on a geometric analysis of the Hamiltonian dynamics constructed from Pontryagin's maximum principle. In a three-level quantum system, we show that the stimulated Raman adiabatic passage technique can be associated to a peculiar Hamiltonian singularity. One deduces that the adiabatic pulse is solution of the optimal control problem only for a specific cost functional. This analysis is extended to the case of a four-level quantum system.

  17. 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

  18. Minimal-Learning-Parameter Technique Based Adaptive Neural Sliding Mode Control of MEMS Gyroscope

    Directory of Open Access Journals (Sweden)

    Bin Xu

    2017-01-01

    Full Text Available This paper investigates an adaptive neural sliding mode controller for MEMS gyroscopes with minimal-learning-parameter technique. Considering the system uncertainty in dynamics, neural network is employed for approximation. Minimal-learning-parameter technique is constructed to decrease the number of update parameters, and in this way the computation burden is greatly reduced. Sliding mode control is designed to cancel the effect of time-varying disturbance. The closed-loop stability analysis is established via Lyapunov approach. Simulation results are presented to demonstrate the effectiveness of the method.

  19. Distinguishing the cognitive processes of mindfulness: Developing a standardised mindfulness technique for use in longitudinal randomised control trials.

    Science.gov (United States)

    Isbel, Ben; Summers, Mathew J

    2017-07-01

    A capacity model of mindfulness is adopted to differentiate the cognitive faculty of mindfulness from the metacognitive processes required to cultivate this faculty in mindfulness training. The model provides an explanatory framework incorporating both the developmental progression from focussed attention to open monitoring styles of mindfulness practice, along with the development of equanimity and insight. A standardised technique for activating these processes without the addition of secondary components is then introduced. Mindfulness-based interventions currently available for use in randomised control trials introduce components ancillary to the cognitive processes of mindfulness, limiting their ability to draw clear causative inferences. The standardised technique presented here does not introduce such ancillary factors, rendering it a valuable tool with which to investigate the processes activated in mindfulness practice. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. 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.)

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

    Science.gov (United States)

    Waugh, R; McCallum, H M; McCarty, M; Montgomery, R; Aszkenasy, M

    2001-05-01

    An audit of paediatric pelvic radiographs identified deficiencies in gonad shield placement and radiographic technique. 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. 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. 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. 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.

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

    International Nuclear Information System (INIS)

    Waugh, R.; McCarty, M.; McCallum, H.M.; Montgomery, R.; Aszkenasy, M.

    2001-01-01

    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.)

  3. Speed control of induction motor using fuzzy recursive least squares technique

    OpenAIRE

    Santiago Sánchez; Eduardo Giraldo

    2008-01-01

    A simple adaptive controller design is presented in this paper, the control system uses the adaptive fuzzy logic, sliding modes and is trained with the recursive least squares technique. The problem of parameter variation is solved with the adaptive controller; the use of an internal PI regulator produces that the speed control of the induction motor be achieved by the stator currents instead the input voltage. The rotor-flux oriented coordinated system model is used to develop and test the c...

  4. Control techniques of tilt rotor unmanned aerial vehicle systems: A review

    Directory of Open Access Journals (Sweden)

    Zhong Liu

    2017-02-01

    Full Text Available The tilt rotor unmanned aerial vehicle (TRUAV exhibits special application value due to its unique rotor structure. However, varying dynamics and aerodynamic interference caused by tiltable rotors are great technical challenges and key issues for TRUAV’s high-powered flight controls, which have attracted the attention of many researchers. This paper outlines the concept of TRUAV and some typical TRUAV platforms while focusing on control techniques. TRUAV structural features, dynamics modeling, and flight control methods are discussed, and major challenges and corresponding developmental tendencies associated with TRUAV flight control are summarized.

  5. Randomised controlled trial of Alexander technique lessons, exercise, and massage (ATEAM) for chronic and recurrent back pain.

    Science.gov (United States)

    Little, Paul; Lewith, George; Webley, Fran; Evans, Maggie; Beattie, Angela; Middleton, Karen; Barnett, Jane; Ballard, Kathleen; Oxford, Frances; Smith, Peter; Yardley, Lucy; Hollinghurst, Sandra; Sharp, Debbie

    2008-08-19

    To determine the effectiveness of lessons in the Alexander technique, massage therapy, and advice from a doctor to take exercise (exercise prescription) along with nurse delivered behavioural counselling for patients with chronic or recurrent back pain. Factorial randomised trial. 64 general practices in England. 579 patients with chronic or recurrent low back pain; 144 were randomised to normal care, 147 to massage, 144 to six Alexander technique lessons, and 144 to 24 Alexander technique lessons; half of each of these groups were randomised to exercise prescription. Normal care (control), six sessions of massage, six or 24 lessons on the Alexander technique, and prescription for exercise from a doctor with nurse delivered behavioural counselling. Roland Morris disability score (number of activities impaired by pain) and number of days in pain. Exercise and lessons in the Alexander technique, but not massage, remained effective at one year (compared with control Roland disability score 8.1: massage -0.58, 95% confidence interval -1.94 to 0.77, six lessons -1.40, -2.77 to -0.03, 24 lessons -3.4, -4.76 to -2.03, and exercise -1.29, -2.25 to -0.34). Exercise after six lessons achieved 72% of the effect of 24 lessons alone (Roland disability score -2.98 and -4.14, respectively). Number of days with back pain in the past four weeks was lower after lessons (compared with control median 21 days: 24 lessons -18, six lessons -10, massage -7) and quality of life improved significantly. No significant harms were reported. One to one lessons in the Alexander technique from registered teachers have long term benefits for patients with chronic back pain. Six lessons followed by exercise prescription were nearly as effective as 24 lessons. National Research Register N0028108728.

  6. Novel temperature control technique for a medicinal herb dryer system powered by a photovoltaic array

    International Nuclear Information System (INIS)

    Abd El-Shafy A Nafeh; Hanaa M Fargali; Faten H Fahmy; Mohamed A Hassan

    2006-01-01

    Each plant has its own optimal drying temperature, especially for the medicinal herbs, because they are sensitive to heat. If the drying temperature becomes more than the optimal value, some chemical reactions will occur and influence the quality of the dried herb, such as color, taste, and aroma. While if the drying temperature becomes lower than the optimal value, the drying process will slow down; and consequently an expected degradation in the quality of the herb may occur, due to insects and fungi infestation which increase in moist conditions. This paper presents a new temperature control technique for a medicinal herb dryer system. The technique fixes the drying temperature of the medicinal herbs at 40 degree C, even in cases of rapidly changing atmospheric conditions. The control of the dryer temperature is achieved through using the proportional integral (PI) controller. The designed dryer contains two systems, which are the thermal and the electrical systems. The thermal system is designed to heat the drying air by using the solar energy and bio-gas fuel. Whereas, the electrical system, which contains a photovoltaic (PV) modules and a battery, is designed to supply the different electrical loads of the dryer system. The control technique is investigated through simulation work by using MATLAB-SIMULINK. The simulation results indicate the high capability of the proposed technique in controlling the drying temperature, even in cases of rapidly changing atmospheric conditions

  7. Simulation model of an active stall wind turbine controller

    Energy Technology Data Exchange (ETDEWEB)

    Jauch, C.; Hansen, A.D.; Soerensen, P. [Risoe National Lab., Wind Energy Dept., Rosilde (Denmark); Blaabjerg, F. [Aalborg Univ., Inst. of Energy Technology (Denmark)

    2004-07-01

    This paper describes an active stall wind turbine controller. The objective is to develop a general model of an active stall controller in order to simulate the operation of grid connected active stall wind turbines. The active stall turbine concept and its control strategies are presented and evaluated on the basis of simulations. The presented controller is described for continuous operation under all wind speeds from start-up wind speed to shut doven wind speed. Due to its parametric implementation it is general i.e. it can represent different active stall wind turbine controllers and can be implemented in different simulation tools. (au)

  8. Moisture Management in an Active Sportswear: Techniques and Evaluation—A Review Article

    Science.gov (United States)

    Senthilkumar, Mani; Sampath, M. B.; Ramachandran, T.

    2012-10-01

    Moisture management property is an important aspect of any fabric meant for active sportswear, which decides the comfort level of that fabric. Every human being sweats during different kinds of activities. An important feature of any fabric is how it transports this water out of the body, so as to make the wearer feel comfortable. This paper reports the concept of moisture management, various production techniques and evaluation of the moisture management characteristics on fabrics for active sportswear.

  9. Expert system and process optimization techniques for real-time monitoring and control of plasma processes

    Science.gov (United States)

    Cheng, Jie; Qian, Zhaogang; Irani, Keki B.; Etemad, Hossein; Elta, Michael E.

    1991-03-01

    To meet the ever-increasing demand of the rapidly-growing semiconductor manufacturing industry it is critical to have a comprehensive methodology integrating techniques for process optimization real-time monitoring and adaptive process control. To this end we have accomplished an integrated knowledge-based approach combining latest expert system technology machine learning method and traditional statistical process control (SPC) techniques. This knowledge-based approach is advantageous in that it makes it possible for the task of process optimization and adaptive control to be performed consistently and predictably. Furthermore this approach can be used to construct high-level and qualitative description of processes and thus make the process behavior easy to monitor predict and control. Two software packages RIST (Rule Induction and Statistical Testing) and KARSM (Knowledge Acquisition from Response Surface Methodology) have been developed and incorporated with two commercially available packages G2 (real-time expert system) and ULTRAMAX (a tool for sequential process optimization).

  10. 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.

  11. Operational techniques employed for the liquid sodium source term control loops

    International Nuclear Information System (INIS)

    Chulos, L.E.

    1976-01-01

    Four Source Term Control Loops (STCLs) have been designed, constructed, and placed into operation at the Hanford Engineering Development Laboratory (HEDL) as part of the Radioactivity Control Technology program. The data obtained are used to determine the corrosion and deposition of LMFBR materials, including corrosion product radionuclides, in a non-isothermal flowing sodium system. The paper discusses operation of the STCL Facilities and, in particular, the methods used for controlling the oxygen content of the liquid sodium. These methods include cold trapping techniques, hot trapping, seeding the cold traps with sodium oxide, and precipitating the oxygen in the cold trap in a controlled manner. Operational problems encountered with the STCL Facilities and the techniques for correcting these problems are also discussed

  12. First Attempts at using Active Halo Control at the LHC

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Joschka [CERN; Bruce, Roderik [CERN; Garcia Morales, Hector [CERN; Höfle, Wolfgang [CERN; Kotzian, Gerd [CERN; Kwee-Hinzmann, Regina [CERN; Langner, Andy [CERN; Mereghetti, Alessio [CERN; Quaranta, Elena [CERN; Redaelli, Stefano [CERN; Rossi, Adriana [CERN; Salvachua, Belen [CERN; Stancari, Giulio [Fermilab; Tomás, Rogelio [CERN; Valentino, Gianluca [CERN; Valuch, Daniel [CERN

    2016-06-01

    The beam halo population is a non-negligible factor for the performance of the LHC collimation system and the machine protection. In particular this could become crucial for aiming at stored beam energies of 700 MJ in the High Luminosity (HL-LHC) project, in order to avoid beam dumps caused by orbit jitter and to ensure safety during a crab cavity failure. Therefore several techniques to safely deplete the halo, i.e. active halo control, are under development. In a first attempt a novel way for safe halo depletion was tested with particle narrow-band excitation employing the LHC Transverse Damper (ADT). At an energy of 450 GeV a bunch selective beam tail scraping without affecting the core distribution was attempted. This paper presents the first measurement results, as well as a simple simulation to model the underlying dynamics.

  13. 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

  14. Determination of radon exhalation rates from tiles using active and passive techniques

    International Nuclear Information System (INIS)

    Al-Jarallah, M.I.; Abu-Jarad, F.; Fazal-ur-Rehman

    2001-01-01

    Measurements of radon exhalation rates for selected samples of tiles used in Saudi Arabia were carried out using active and passive measuring techniques. These samples were granite, marble and ceramic. In the active method, a PC-based radon gas analyzer with emanation container was used, while, in the passive method, PM-355 nuclear track detectors with the 'can technique' were applied for 180 days. A comparison of the exhalation rates measured by the two techniques showed a good linear correlation coefficient of 0.7. The granite samples showed an average radon exhalation rate of 0.7 Bq m -2 h -1 , which was higher than that of marble and ceramic by more than twofold. The radon exhalation rates measured by the 'can technique' showed a non-uniform exhalation from the surface of the same tile

  15. Determination of radon exhalation rates from tiles using active and passive techniques

    Energy Technology Data Exchange (ETDEWEB)

    Al-Jarallah, M.I. E-mail: mibrahim@kfupm.edu.sa; Abu-Jarad, F.; Fazal-ur-Rehman

    2001-06-01

    Measurements of radon exhalation rates for selected samples of tiles used in Saudi Arabia were carried out using active and passive measuring techniques. These samples were granite, marble and ceramic. In the active method, a PC-based radon gas analyzer with emanation container was used, while, in the passive method, PM-355 nuclear track detectors with the 'can technique' were applied for 180 days. A comparison of the exhalation rates measured by the two techniques showed a good linear correlation coefficient of 0.7. The granite samples showed an average radon exhalation rate of 0.7 Bq m{sup -2} h{sup -1}, which was higher than that of marble and ceramic by more than twofold. The radon exhalation rates measured by the 'can technique' showed a non-uniform exhalation from the surface of the same tile.

  16. 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.

  17. 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.

  18. Active controllers and the time duration to learn a task

    Science.gov (United States)

    Repperger, D. W.; Goodyear, C.

    1986-01-01

    An active controller was used to help train naive subjects involved in a compensatory tracking task. The controller is called active in this context because it moves the subject's hand in a direction to improve tracking. It is of interest here to question whether the active controller helps the subject to learn a task more rapidly than the passive controller. Six subjects, inexperienced to compensatory tracking, were run to asymptote root mean square error tracking levels with an active controller or a passive controller. The time required to learn the task was defined several different ways. The results of the different measures of learning were examined across pools of subjects and across controllers using statistical tests. The comparison between the active controller and the passive controller as to their ability to accelerate the learning process as well as reduce levels of asymptotic tracking error is reported here.

  19. Prompt Gamma Activation Analysis (PGAA): Technique of choice for nondestructive bulk analysis of returned comet samples

    International Nuclear Information System (INIS)

    Lindstrom, D.J.; Lindstrom, R.M.

    1989-01-01

    Prompt gamma activation analysis (PGAA) is a well-developed analytical technique. The technique involves irradiation of samples in an external neutron beam from a nuclear reactor, with simultaneous counting of gamma rays produced in the sample by neutron capture. Capture of neutrons leads to excited nuclei which decay immediately with the emission of energetic gamma rays to the ground state. PGAA has several advantages over other techniques for the analysis of cometary materials: (1) It is nondestructive; (2) It can be used to determine abundances of a wide variety of elements, including most major and minor elements (Na, Mg, Al, Si, P, K, Ca, Ti, Cr, Mn, Fe, Co, Ni), volatiles (H, C, N, F, Cl, S), and some trace elements (those with high neutron capture cross sections, including B, Cd, Nd, Sm, and Gd); and (3) It is a true bulk analysis technique. Recent developments should improve the technique's sensitivity and accuracy considerably

  20. Metabolic mapping of functional activity in human subjects with the [18F]fluorodeoxyglucose technique

    International Nuclear Information System (INIS)

    Greenberg, J.H.; Reivich, M.; Alavi, A.

    1981-01-01

    The 2-[ 18 F]fluoro-2-deoxy-D-glucose technique was used to measure regional cerebral glucose utilization by human subjects during functional activation. Normal male volunteers subjected to one or more sensory stimuli exhibited focal increases in glucose metabolism in response to the stimulus. These results demonstrate that the technique is capable of providing functional maps in vivo related to both body region and submodality of sensory information in the human brain

  1. A novel and alternative approach to controlled release drug delivery system based on solid dispersion technique

    Directory of Open Access Journals (Sweden)

    Tapan Kumar Giri

    2012-12-01

    Full Text Available The solid dispersion method was originally used to improve the dissolution properties and the bioavailability of poorly water soluble drugs by dispersing them into water soluble carriers. In addition to the above, dissolution retardation through solid dispersion technique using water insoluble and water swellable polymer for the development of controlled release dosage forms has become a field of interest in recent years. Development of controlled release solid dispersion has a great advantage for bypassing the risk of a burst release of drug; since the structure of the solid dispersion is monolithic where drug molecules homogeneously disperse. Despite the remarkable potential and extensive research being conducted on controlled release solid dispersion system, commercialization and large scale production are limited. The author expects that recent technological advances may overcome the existing limitations and facilitate the commercial utilization of the techniques for manufacture of controlled release solid dispersions. This article begins with an overview of the different carriers being used for the preparation of controlled release solid dispersion and also different techniques being used for the purpose. Kinetics of drug release from these controlled release solid dispersions and the relevant mathematical modeling have also been reviewed in this manuscript.

  2. Low Activity Waste Feed Process Control Strategy

    International Nuclear Information System (INIS)

    STAEHR, T.W.

    2000-01-01

    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

  3. Controlling active cabin suspensions in commercial vehicles

    NARCIS (Netherlands)

    Evers, W.J.E.; Besselink, I.J.M.; Teerhuis, A.P.; Knaap, van der A.C.M.; Nijmeijer, H.

    2009-01-01

    The field of automotive suspensions is changing. Semi-active and active suspensions are starting to become viable options for vehicle designers. Suspension design for commercial vehicles is especially interesting given its potential. An active cabin suspension for a heavy-duty truck is considered,

  4. Active control versus recursive backstepping control of a chaotic ...

    African Journals Online (AJOL)

    ... than for the recursive backstepping controllers. However, the flexibility in the choice of the control laws for recursive backstepping design gives room for further improvement in its performance and enables it to achieve the goals of stabilization and tracking. Journal of the Nigerian Association of Mathematical Physics Vol.

  5. Nuclear techniques for bulk ore analysis and their application to quality control

    International Nuclear Information System (INIS)

    Holmes, R.J.

    1981-01-01

    Bulk analysis techniques developed for the mining industry in which analyses are obtained directly from 3-30kg ore samples or from ore on conveyor belts are outlined. They include the determination of iron in iron ores from backscattered gamma radiation, shale in sedimentary iron ores from natural gamma activity, iron from a thermal-neutron capture reaction, and aluminium from the thermal neutron activation reaction

  6. Development of the staffing evaluation technique for mental tasks of the advanced main control room

    International Nuclear Information System (INIS)

    Hsieh Tsungling; Yang Chihwei; Lin Chiuhsiangjoe

    2011-01-01

    The key goals of staffing and qualifications review element are to ensure that the right numbers of people with the appropriate skills and abilities are available to support plant operations and events. If the staffing level is too few, excessive stress that caused human errors possibly will be placed on the operators. Accordingly, this study developed a staffing evaluation technique based on CPM-GOMS for the mental tasks such as operations in the advanced main control room. A within-subject experiment was designed to examine the validity of the staffing evaluation technique. The results indicated the performance of evaluated staffing level via the staffing evaluation technique was significantly higher than that of non-evaluated staffing level; thus, validity of the staffing evaluation technique can be accepted. Finally, the implications for managerial practice on the findings of this study were discussed. (author)

  7. Quality control for total evaporation technique by surface/thermal ionization mass spectrometer

    International Nuclear Information System (INIS)

    Kato, Seikou; Inoue, Sinichi; Yamaguchi, Katsuyuki; Tsutaki, Yasuhiro

    2007-01-01

    For the measurement of uranium and plutonium isotopic composition, the surface/thermal ionization mass spectrometry is widely used at the both nuclear facilities and safeguards verification laboratories. The progress of instrument specification makes higher sensitivity. The total evaporation technique is one of the latest measurement techniques by using this progress, in which all of uranium or plutonium on the filament would be evaporated by increasing the filament current. The accuracy and precision of this technique is normally checked by using the certified isotope reference materials measurement. But the fluctuation of ion beam is very different by each filament, depending on the chemical form of evaporation. So, it should be considered how to check the measurement quality of unknown samples which has no certified values. This presentation is focused on the monitoring of ion yields and pattern of isotope ratio fluctuation to attain the traceability between reference material and unknown sample as quality control approach of total evaporation technique. (author)

  8. Flight Flutter Testing of Rotary Wing Aircraft Using a Control System Oscillation Technique

    Science.gov (United States)

    Yen, J. G.; Viswanathan, S.; Matthys, C. G.

    1976-01-01

    A flight flutter testing technique is described in which the rotor controls are oscillated by series actuators to excite the rotor and airframe modes of interest, which are then allowed to decay. The moving block technique is then used to determine the damped frequency and damping variation with rotor speed. The method proved useful for tracking the stability of relatively well damped modes. The results of recently completed flight tests of an experimental soft-in-plane rotor are used to illustrate the technique. Included is a discussion of the application of this technique to investigation of the propeller whirl flutter stability characteristics of the NASA/Army XV-15 VTOL tilt rotor research aircraft.

  9. Application of the partitive analytical forecasting (PAF) technique to the United States controlled thermonuclear research effort

    International Nuclear Information System (INIS)

    Nichols, S.P.

    1975-01-01

    The Partitive Analytical Forecasting (PAF) technique is applied to the overall long-term program plans for the Division of Controlled Thermonuclear Research (DCTR) of the United States Energy Research and Development Administration (ERDA). As part of the PAF technique, the Graphical Evaluation and Review Technique (GERTS) IIIZ computer code is used to perform simulations on a logic network describing the DCTR long-term program plan. Logic networks describing the tokamak, mirror, and theta-pinch developments are simulated individually and then together to form an overall DCTR program network. The results of the simulation of the overall network using various funding schemes and strategies are presented. An economic sensitivity analysis is provided for the tokamak logic networks. An analysis is also performed of the fusion-fission hybrid concept in the context of the present DCTR goals. The results mentioned above as well as the PAF technique itself are evaluated, and recommendations for further research are discussed

  10. The effect of a 3-month prevention program on the jump-landing technique in basketball: a randomized controlled trial.

    Science.gov (United States)

    Aerts, Inne; Cumps, Elke; Verhagen, Evert; Wuyts, Bram; Van De Gucht, Sam; Meeusen, Romain

    2015-02-01

    In jump-landing sports, the injury mechanism that most frequently results in an injury is the jump-landing movement. Influencing the movement patterns and biomechanical predisposing factors are supposed to decrease injury occurrence. To evaluate the influence of a 3-mo coach-supervised jump-landing prevention program on jump-landing technique using the jump-landing scoring (JLS) system. Randomized controlled trial. On-field. 116 athletes age 15-41 y, with 63 athletes in the control group and 53 athletes in the intervention group. The intervention program in this randomized control trial was administered at the start of the basketball season 2010-11. The jump-landing training program, supervised by the athletic trainers, was performed for a period of 3 mo. The jump-landing technique was determined by registering the jump-landing technique of all athletes with the JLS system, pre- and postintervention. After the prevention program, the athletes of the male and female intervention groups landed with a significantly less erect position than those in the control groups (P < .05). This was presented by a significant improvement in maximal hip flexion, maximal knee flexion, hip active range of motion, and knee active range of motion. Another important finding was that postintervention, knee valgus during landing diminished significantly (P < .05) in the female intervention group compared with their control group. Furthermore, the male intervention group significantly improved (P < .05) the scores of the JLS system from pre- to postintervention. Malalignments such as valgus position and insufficient knee flexion and hip flexion, previously identified as possible risk factors for lower-extremity injuries, improved significantly after the completion of the prevention program. The JLS system can help in identifying these malalignments. Therapy, prevention, level 1b.

  11. Monitoring by Control Technique - Compliant (Low/No VOC/HAP) Inks and Coatings

    Science.gov (United States)

    Stationary source emissions monitoring is required to demonstrate that a source is meeting the requirements in Federal or state rules. This page is about Compliant (Low/No VOC/HAP) Inks and Coatings control techniques used to reduce pollutant emissions.

  12. Project orie:nta.teci pla.:n:ni:ng, scheduling a.:nci controlling technique

    African Journals Online (AJOL)

    Review Technique. By October 1958 it ... (CPM) to schedule and control a very large project. and during the ... objectives are identified and the total job is broken down into ..... jobs in a single shop or shops in the plant, to scheduf- ing plants ...

  13. Nuclear techniques in plant pathology 1. Plant disease control and physiology of parasitism

    International Nuclear Information System (INIS)

    Menten, J.O.M.; Ando, A.; Tulmann Neto, A.

    1986-01-01

    Nuclear techniques are advantageously used in several areas of plant pathology. Among them are: induction of mutation for disease resistance, studies with pesticides, disease control through pathogen inactivation, induction of variability and stimulation in pathogens and natural enemies, studies of microorganism physiology and diseased plant physiology, effect of gamma radiation on pesticides, technology of pesticides application, etc. (Author) [pt

  14. Technique, muscle activity and kinematic differences in young adults texting on mobile phones.

    Science.gov (United States)

    Gustafsson, Ewa; Johnson, Peter W; Lindegård, Agneta; Hagberg, Mats

    2011-05-01

    The aim of this study was to investigate whether there are differences in technique between young adults with and without musculoskeletal symptoms when using a mobile phone for texting and whether there are differences in muscle activity and kinematics between different texting techniques. A total of 56 young adults performed a standardised texting task on a mobile phone. Their texting techniques were registered using an observation protocol. The muscular activity in six muscles in the right forearm/hand and both shoulders were registered by surface electromyography and the thumb abduction/adduction and flexion/extension were registered using a biaxial electrogoniometer. Differences in texting techniques were found between the symptomatic and the asymptomatic group, with a higher proportion of sitting with back support and forearm support and with a neutral head position in the asymptomatic group. Differences in muscle activity and kinematics were also found between different texting techniques. The differences in texting technique between symptomatic and asymptomatic subjects cannot be explained by them having symptoms but may be a possible contribution to their symptoms. STATEMENT OF RELEVANCE: There has been a dramatically increased use of mobile phones for texting especially among young people during the last years. A better understanding of the physical exposure associated with the intensive use is important in order to prevent the development of musculoskeletal disorders and decreased work ability related to this use.

  15. Cooking techniques improve the levels of bioactive compounds and antioxidant activity in kale and red cabbage.

    Science.gov (United States)

    Murador, Daniella Carisa; Mercadante, Adriana Zerlotti; de Rosso, Veridiana Vera

    2016-04-01

    The aim of this study is to investigate the effects of different home cooking techniques (boiling, steaming, and stir-frying) in kale and red cabbage, on the levels of bioactive compounds (carotenoids, anthocyanins and phenolic compounds) determined by high-performance liquid chromatography coupled with photodiode array and mass spectrometry detectors (HPLC-DAD-MS(n)), and on the antioxidant activity evaluated by ABTS, ORAC and cellular antioxidant activity (CAA) assays. The steaming technique resulted in a significant increase in phenolic content in kale (86.1%; pkale, steaming resulted in significant increases in antioxidant activity levels in all of the evaluation methods. In the red cabbage, boiling resulted in a significant increase in antioxidant activity using the ABTS assay but resulted in a significant decrease using the ORAC assay. According to the CAA assay, the stir-fried sample displayed the highest levels of antioxidant activity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Advanced control techniques for post-buckled precompressed (PBP) flight control actuators

    NARCIS (Netherlands)

    Groen, M.; Van Schravendijk, M.; Barrett, R.; Vos, R.

    2009-01-01

    The dynamic response of a new class of flight control actuators that rely on post-buckled recompressed (PBP) piezoelectric elements is investigated. While past research has proven that PBP actuators are capable of generating deflections three times higher than conventional bimorph actuators, this

  17. Interference Mitigation Technique Using Active Spaceborne Sensor Antenna in EESS (Active) and Space Research Service (Active) for Use in 500 MHz Bandwidth Near 9.6 GHz

    Science.gov (United States)

    Huneycutt, Bryan L.

    2005-01-01

    This document presents an interference mitigation technique using the active spaceborne sensor SAR3 antenna in the Earth Exploration-Satellite Service (active) and Space Research Service (active) for use in a 500 MHz bandwidth near 9.6 GHz. The purpose of the document is present antenna designs which offer lower sidelobes and faster rolloff in the sidelobes which in turn mitigates the interference to other services from the EESS (active) and SRS (active) sensors.

  18. Nonlinear control techniques of a controllable rectifier/inverter-motor drive system with a small dc-link capacitor

    International Nuclear Information System (INIS)

    Liutanakul, Pisit; Pierfederici, Serge; Meibody-Tabar, Farid

    2008-01-01

    The necessity of the converters compactness in many applications imposes the reduction of their different components size when it is possible. In this paper, a control method allowing the use of a small size dc-link capacitor for the cascade of voltage controlled-rectifier/inverter-motor drive system is proposed. This is achieved by adding the power balance equation in the system's model and the application of an exact input/output feedback linearization technique in a way that the rectifier controller compensates any sudden change in the inverter load, which is here an induction motor. Since the exact input/output feedback linearization technique is sensitive to the uncertainties over system parameters, a robust control strategy based on sliding mode controller is proposed. By this approach, the dc-link voltage becomes almost insensitive to the load variations. As a result, the level of the dc-link voltage could be stabilized with a small size dc-link capacitor. Without any considerations of the RMS current stress on this dc-link capacitor, a calculation method of a minimum value of this capacitor based on its storage energy is proposed. All the investigations are shown by computer simulations and the performance of controlled system is verified by experimentation results

  19. 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.

  20. Control of radioactive contamination and radiation exposure in the environment - tasks, techniques, implementation

    International Nuclear Information System (INIS)

    Bayer, A.

    1997-01-01

    A brief historical abstract of the steps in the discovery of natural radioactivity and development of man-made radioactivity is presented, as well as the historical development of the control of radioactivity in the environment. The goals of control measures and the tasks, classified by the possible sources of release, are demonstrated and the required methods described (measuring methods, evaluation methods, and information techniques). The control measures, based on different legal principles, are introduced and their technological implementation, including their current status, described. Finally, an account is given of the progressive harmonisation of the national control systems, as well as of the integration of these control systems into international control and information networks. (orig.) [de

  1. 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.

  2. Active vibration control of spatial flexible multibody systems

    International Nuclear Information System (INIS)

    Neto, Maria Augusta; Ambrósio, Jorge A. C.; Roseiro, Luis M.; Amaro, A.; Vasques, C. M. A.

    2013-01-01

    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.

  3. 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.

  4. A hybrid firefly algorithm and pattern search technique for SSSC based power oscillation damping controller design

    Directory of Open Access Journals (Sweden)

    Srikanta Mahapatra

    2014-12-01

    Full Text Available In this paper, a novel hybrid Firefly Algorithm and Pattern Search (h-FAPS technique is proposed for a Static Synchronous Series Compensator (SSSC-based power oscillation damping controller design. The proposed h-FAPS technique takes the advantage of global search capability of FA and local search facility of PS. In order to tackle the drawback of using the remote signal that may impact reliability of the controller, a modified signal equivalent to the remote speed deviation signal is constructed from the local measurements. The performances of the proposed controllers are evaluated in SMIB and multi-machine power system subjected to various transient disturbances. To show the effectiveness and robustness of the proposed design approach, simulation results are presented and compared with some recently published approaches such as Differential Evolution (DE and Particle Swarm Optimization (PSO. It is observed that the proposed approach yield superior damping performance compared to some recently reported approaches.

  5. Exploring Techniques for Vision Based Human Activity Recognition: Methods, Systems, and Evaluation

    Directory of Open Access Journals (Sweden)

    Hong Zhang

    2013-01-01

    Full Text Available With the wide applications of vision based intelligent systems, image and video analysis technologies have attracted the attention of researchers in the computer vision field. In image and video analysis, human activity recognition is an important research direction. By interpreting and understanding human activity, we can recognize and predict the occurrence of crimes and help the police or other agencies react immediately. In the past, a large number of papers have been published on human activity recognition in video and image sequences. In this paper, we provide a comprehensive survey of the recent development of the techniques, including methods, systems, and quantitative evaluation towards the performance of human activity recognition.

  6. Directional tip control technique for optimal stent graft alignment in angulated proximal aortic landing zones

    Directory of Open Access Journals (Sweden)

    Toshio Takayama, MD, PhD

    2017-06-01

    Full Text Available Angulated anatomy in the aorta, such as tortuous infrarenal aortic necks or steep aortic arches, is a significant challenge for endovascular aortic repair because it often causes inadequate sealing and fixation, which may lead to treatment failure. We have developed a technique using off-the-shelf equipment to precisely control the deployment of stent grafts in challenging landing zones. The key of this technique is to create a through-and-through wire between two access sites and to use a guiding device over the wire. This technique is best used with stent grafts without nose cones. We present an endovascular aneurysm repair case and a thoracic endovascular aortic repair case with challenging proximal landing zones treated by this technique. In both cases, technical success was attained, and follow-up imaging demonstrated well-aligned stent grafts. Our directional tip control technique is easy and effective. It can be a good technical solution for endovascular aortic treatment in angulated anatomy.

  7. A two isocenter IMRT technique with a controlled junction dose for long volume targets

    International Nuclear Information System (INIS)

    Zeng, G G; Heaton, R K; Catton, C N; Chung, P W; O'Sullivan, B; Lau, M; Parent, A; Jaffray, D A

    2007-01-01

    Most IMRT techniques have been designed to treat targets smaller than the field size of conventional linac accelerators. In order to overcome the field size restrictions in applying IMRT, we developed a two isocenter IMRT technique to treat long volume targets. The technique exploits an extended dose gradient throughout a junction region of 4-6 cm to minimize the impact of field match errors on a junction dose and manipulates the inverse planning and IMRT segments to fill in the dose gradient and achieve dose uniformity. Techniques for abutting both conventional fields with IMRT ('Static + IMRT') and IMRT fields ('IMRT + IMRT') using two separate isocenters have been developed. Five long volume sarcoma cases have been planned in Pinnacle (Philips, Madison, USA) using Elekta Synergy and Varian 2100EX linacs; two of the cases were clinically treated with this technique. Advantages were demonstrated with well-controlled junction target uniformity and tolerance to setup uncertainties. The junction target dose heterogeneity was controlled at a level of ±5%; for 3 mm setup errors at the field edges, the junction target dose changed less than 5% and the dose sparing to organs at risk (OARs) was maintained. Film measurements confirmed the treatment planning results

  8. Behavior change techniques implemented in electronic lifestyle activity monitors: a systematic content analysis.

    Science.gov (United States)

    Lyons, Elizabeth J; Lewis, Zakkoyya H; Mayrsohn, Brian G; Rowland, Jennifer L

    2014-08-15

    Electronic activity monitors (such as those manufactured by Fitbit, Jawbone, and Nike) improve on standard pedometers by providing automated feedback and interactive behavior change tools via mobile device or personal computer. These monitors are commercially popular and show promise for use in public health interventions. However, little is known about the content of their feedback applications and how individual monitors may differ from one another. The purpose of this study was to describe the behavior change techniques implemented in commercially available electronic activity monitors. Electronic activity monitors (N=13) were systematically identified and tested by 3 trained coders for at least 1 week each. All monitors measured lifestyle physical activity and provided feedback via an app (computer or mobile). Coding was based on a hierarchical list of 93 behavior change techniques. Further coding of potentially effective techniques and adherence to theory-based recommendations were based on findings from meta-analyses and meta-regressions in the research literature. All monitors provided tools for self-monitoring, feedback, and environmental change by definition. The next most prevalent techniques (13 out of 13 monitors) were goal-setting and emphasizing discrepancy between current and goal behavior. Review of behavioral goals, social support, social comparison, prompts/cues, rewards, and a focus on past success were found in more than half of the systems. The monitors included a range of 5-10 of 14 total techniques identified from the research literature as potentially effective. Most of the monitors included goal-setting, self-monitoring, and feedback content that closely matched recommendations from social cognitive theory. Electronic activity monitors contain a wide range of behavior change techniques typically used in clinical behavioral interventions. Thus, the monitors may represent a medium by which these interventions could be translated for

  9. 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.

  10. 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.

  11. 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)

    1996-12-31

    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.

  12. 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

  13. MAG4 versus alternative techniques for forecasting active region flare productivity

    Science.gov (United States)

    Falconer, David A; Moore, Ronald L; Barghouty, Abdulnasser F; Khazanov, Igor

    2014-01-01

    MAG4 is a technique of forecasting an active region's rate of production of major flares in the coming few days from a free magnetic energy proxy. We present a statistical method of measuring the difference in performance between MAG4 and comparable alternative techniques that forecast an active region's major-flare productivity from alternative observed aspects of the active region. We demonstrate the method by measuring the difference in performance between the “Present MAG4” technique and each of three alternative techniques, called “McIntosh Active-Region Class,” “Total Magnetic Flux,” and “Next MAG4.” We do this by using (1) the MAG4 database of magnetograms and major flare histories of sunspot active regions, (2) the NOAA table of the major-flare productivity of each of 60 McIntosh active-region classes of sunspot active regions, and (3) five technique performance metrics (Heidke Skill Score, True Skill Score, Percent Correct, Probability of Detection, and False Alarm Rate) evaluated from 2000 random two-by-two contingency tables obtained from the databases. We find that (1) Present MAG4 far outperforms both McIntosh Active-Region Class and Total Magnetic Flux, (2) Next MAG4 significantly outperforms Present MAG4, (3) the performance of Next MAG4 is insensitive to the forward and backward temporal windows used, in the range of one to a few days, and (4) forecasting from the free-energy proxy in combination with either any broad category of McIntosh active-region classes or any Mount Wilson active-region class gives no significant performance improvement over forecasting from the free-energy proxy alone (Present MAG4). Key Points Quantitative comparison of performance of pairs of forecasting techniques Next MAG4 forecasts major flares more accurately than Present MAG4 Present MAG4 forecast outperforms McIntosh AR Class and total magnetic flux PMID:26213517

  14. Techniques for developing reliable and functional materials control and accounting software

    International Nuclear Information System (INIS)

    Barlich, G.

    1988-01-01

    The media has increasingly focused on failures of computer systems resulting in financial, material, and other losses and on systems failing to function as advertised. Unfortunately, such failures with equally disturbing losses are possible in computer systems providing materials control and accounting (MCandA) functions. Major improvements in the reliability and correctness of systems are possible with disciplined design and development techniques applied during software development. This paper describes some of the techniques used in the Safeguard Systems Group at Los Alamos National Laboratory for various MCandA systems

  15. Application of object oriented techniques in the TRIUMF beam line 2C control system

    International Nuclear Information System (INIS)

    Wilkinson, N.A.; Ludgate, G.A.

    1992-07-01

    The KAON Factory central control system study employed a uniform approach to requirements analysis, architectural design and programming based on well established object oriented principles. These principles were applied to the successful analysis, design and implementation of the control system for the TRIUMF Beam Line 2C Solid Target Facility. The specification for this control system was created in collaboration with Beam Line 2C equipment management experts and, once the analysis models were validated, an approach was developed for the direct translation of these models into C code. A commercial real time database was central to this translation, as inter-object data and control flows are implemented by channels in the database. This paper focuses on the experience gained in the use of object oriented techniques during the complete analysis-design-implementation cycle of a working control system and on the utility of implementing such a system using a commercial real time database and graphical interface. (author)

  16. Review of Control Techniques for HVAC Systems—Nonlinearity Approaches Based on Fuzzy Cognitive Maps

    Directory of Open Access Journals (Sweden)

    Farinaz Behrooz

    2018-02-01

    Full Text Available Heating, Ventilating, and Air Conditioning (HVAC systems are the major energy-consuming devices in buildings. Nowadays, due to the high demand for HVAC system installation in buildings, designing an effective controller in order to decrease the energy consumption of the devices while meeting the thermal comfort demands in buildings are the most important goals of control designers. The purpose of this article is to investigate the different control methods for Heating, Ventilating, and Air Conditioning and Refrigeration (HVAC & R systems. The advantages and disadvantages of each control method are discussed and finally the Fuzzy Cognitive Map (FCM method is introduced as a new strategy for HVAC systems. The FCM method is an intelligent and advanced control technique to address the nonlinearity, Multiple-Input and Multiple-Output (MIMO, complexity and coupling effect features of the systems. The significance of this method and improvements by this method are compared with other methods.

  17. Nonlinear techniques for forecasting solar activity directly from its time series

    Science.gov (United States)

    Ashrafi, S.; Roszman, L.; Cooley, J.

    1993-01-01

    This paper presents numerical techniques for constructing nonlinear predictive models to forecast solar flux directly from its time series. This approach makes it possible to extract dynamical in variants of our system without reference to any underlying solar physics. We consider the dynamical evolution of solar activity in a reconstructed phase space that captures the attractor (strange), give a procedure for constructing a predictor of future solar activity, and discuss extraction of dynamical invariants such as Lyapunov exponents and attractor dimension.

  18. Ex vivo activity quantification in micrometastases at the cellular scale using the α-camera technique

    DEFF Research Database (Denmark)

    Chouin, Nicolas; Lindegren, Sture; Frost, Sofia H L

    2013-01-01

    Targeted α-therapy (TAT) appears to be an ideal therapeutic technique for eliminating malignant circulating, minimal residual, or micrometastatic cells. These types of malignancies are typically infraclinical, complicating the evaluation of potential treatments. This study presents a method of ex...... vivo activity quantification with an α-camera device, allowing measurement of the activity taken up by tumor cells in biologic structures a few tens of microns....

  19. 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.

  20. Robust control for a biaxial servo with time delay system based on adaptive tuning technique.

    Science.gov (United States)

    Chen, Tien-Chi; Yu, Chih-Hsien

    2009-07-01

    A robust control method for synchronizing a biaxial servo system motion is proposed in this paper. A new network based cross-coupled control and adaptive tuning techniques are used together to cancel out the skew error. The conventional fixed gain PID cross-coupled controller (CCC) is replaced with the adaptive cross-coupled controller (ACCC) in the proposed control scheme to maintain biaxial servo system synchronization motion. Adaptive-tuning PID (APID) position and velocity controllers provide the necessary control actions to maintain synchronization while following a variable command trajectory. A delay-time compensator (DTC) with an adaptive controller was augmented to set the time delay element, effectively moving it outside the closed loop, enhancing the stability of the robust controlled system. This scheme provides strong robustness with respect to uncertain dynamics and disturbances. The simulation and experimental results reveal that the proposed control structure adapts to a wide range of operating conditions and provides promising results under parameter variations and load changes.

  1. Nitrate control strategies in an activated sludge wastewater treatment process

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Wenhao; Tao, Erpan; Chen, Xiaoquan; Liu, Dawei [South China University of Technology, Guangzhou (China); Liu, Hongbin [Kyung Hee University, Yongin (Korea, Republic of)

    2014-03-15

    We studied nitrate control strategies in an activated sludge wastewater treatment process (WWTP) based on the activated sludge model. Two control strategies, back propagation for proportional-integral-derivative (BP-PID) and adaptive-network based fuzzy inference systems (ANFIS), are applied in the WWTP. The simulation results show that the simple local constant setpoint control has poor control effects on the nitrate concentration control. However, the ANFIS (4*1) controller, which considers not only the local constant setpoint control of the nitrate concentration, but also three important indices in the effluent--ammonia concentration, total suspended sludge concentration and total nitrogen concentration--demonstrates good control performance. The results also prove that ANFIS (4*1) controller has better control performance than that of the controllers PI, BP-PID and ANFIS (2*1), and that the ANFIS (4*1) controller is effective in improving the effluent quality and maintaining the stability of the effluent quality.

  2. Effectiveness of teaching cognitive-behavioral techniques on locus of control in hemodialysis patients.

    Science.gov (United States)

    Mehrtak, Mohammad; Habibzadeh, Shahram; Farzaneh, Esmaeil; Rjaei-Khiavi, Abdollah

    2017-10-01

    Many of the cognitive behavioral models and therapeutic protocols developed so far for psychological disorders and chronic diseases have proved effective through clinical research. This study aimed to determine the effectiveness of teaching cognitive-behavioral techniques on locus of control in hemodialysis patients. This controlled clinical trial study was conducted in 2015 with 76 patients selected by census and treated with a hemodialysis machine in the dialysis department of Vali-Asr Hospital in the city of Meshkinshahr. A total of four patients were excluded because of their critical conditions while the rest, who were recruited, were randomly divided into two equal groups of 36 patients as the intervention and control groups. First, the locus of control was measured in both groups through a pretest, and cognitive-behavioral techniques were then taught to the intervention group during eight 45 to 90-minute sessions. The locus of control in patients of both groups was finally re-measured through a posttest. Data were collected using Rotter's Locus of Control Inventory. The Wilcoxon test and Mann-Whitney U test were respectively used in SPSS18 for data analysis. In the pretest and posttest stages respectively, 4.8% and 14.3% of samples in the control group as well as 14.3% and 33.3% of samples in the intervention group enjoyed internal locus of control. The difference between the pretest and posttest scores of internal locus of control in the intervention group was significant (p=0.004), which indicates the positive effect of cognitive-behavioral psychotherapeutic intervention on internalization of locus of control in this group. Given the external locus of control in most of the study patients and also the positive significant effect of cognitive-behavioral psychotherapy on internalization of locus of control in this group of patients, it appears necessary to have a psychology resident present in the hemodialysis department to teach the necessary cognitive

  3. Quality control of total alpha and beta activity analysis in water using the Proportional Counter of Gaseous Flux technique; Controle de qualidade das análises de atividades alfa e beta total em água pela técnica do Contador Proporcional de Fluxo Gasoso

    Energy Technology Data Exchange (ETDEWEB)

    Neto, Alberto P.; Bastos, Thiago M.R.; Santos, Thiago O.; Filho, Crescêncio A.S.; França, Elvis J. de, E-mail: albertopereiran@gmail.com, E-mail: thiagomrbastos@gmail.com, E-mail: thiago_cbufpe@yahoo.com.br, E-mail: candrade@cnen.gov.br, E-mail: ejfranca@cnen.gov.br [Centro Regional de Ciências Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

    2017-07-01

    The analytical capacity of the CRCN (Centro Regional de Ciências Nucleares do Nordeste) for quantification of total alpha and beta concentrations in water samples using the Proportional Counter of Gaseous Flux is presented. To demonstrate the traceability of the results, the National Intercomparison Program (PNI) samples were used, promoted by the Institute of Radioprotection and Dosimetry (IRD) from which the Regional Nuclear Science Center of the Northeast (CRCN-NE) participates since 2011. The results reported to the PNI demonstrate the analytical capacity of the CRCN to detect the emission of alpha and beta radioactivities in water within the potability standards in analytical detection of quantification in radioactivity by the technique of the Proportional Flow Counter.

  4. Advanced chemical quality control techniques for use in the manufacture of (U-Pu) MOX fuels

    International Nuclear Information System (INIS)

    Panakkal, J.P.; Prakash, Amrit

    2010-01-01

    Analytical chemistry plays a very important role for nuclear fuel cycle activities be it fuel fabrication, waste management or reprocessing. Nuclear fuels are selected based on the type of reactor. The nuclear fuel has to conform to various stringent chemical specifications like B, rare earths, H, O/M heavy metal content etc. Selection of technique is very important to determine the true specification. This is important particularly when the analyses has to be performed inside leak tight enclosure. The present paper describes the details of the advanced techniques being developed and used in the manufacture of (U,Pu) MOX fuels. (author)

  5. Nonlinear Predictive Sliding Mode Control for Active Suspension System

    Directory of Open Access Journals (Sweden)

    Dazhuang Wang

    2018-01-01

    Full Text Available An active suspension system is important in meeting the requirements of the ride comfort and handling stability for vehicles. In this work, a nonlinear model of active suspension system and a corresponding nonlinear robust predictive sliding mode control are established for the control problem of active suspension. Firstly, a seven-degree-of-freedom active suspension model is established considering the nonlinear effects of springs and dampers; and secondly, the dynamic model is expanded in the time domain, and the corresponding predictive sliding mode control is established. The uncertainties in the controller are approximated by the fuzzy logic system, and the adaptive controller reduces the approximation error to increase the robustness of the control system. Finally, the simulation results show that the ride comfort and handling stability performance of the active suspension system is better than that of the passive suspension system and the Skyhook active suspension. Thus, the system can obviously improve the shock absorption performance of vehicles.

  6. Current activities in development of PIE techniques in JMTR hot laboratory

    International Nuclear Information System (INIS)

    Ishii, Toshimitsu; Ohmi, Masao; Shimizu, Michio; Kaji, Yoshiyuki; Ueno, Fumiyoshi

    2006-01-01

    A wide variety of post-irradiation examinations (PIEs) for research and development of nuclear fuels and materials to be utilized in nuclear field has been carried out since 1971 in three kinds of β-γ hot cells; concrete, lead and steel cells in the JMTR Hot Laboratory (JMTR HL) associated with the Japan Materials Testing Reactor (JMTR). In addition to PIEs, the re-capsuling work including re-instrumentation was also conducted for the power ramping tests of the irradiated LWR fuels using Boiling Water Capsule (BOCA). Recently, new PIE techniques are required for the advanced irradiation studies. In this paper, the irradiation assisted stress corrosion cracking (IASCC) growth test technique of irradiated in-core structural materials and the remote operation technique of the atomic force microscope (AFM) are described as JMTR HL's current activities in the development of new PIE techniques. (author)

  7. Activity identification using body-mounted sensors—a review of classification techniques

    International Nuclear Information System (INIS)

    Preece, Stephen J; Kenney, Laurence P J; Howard, Dave; Goulermas, John Y; Crompton, Robin; Meijer, Kenneth

    2009-01-01

    With the advent of miniaturized sensing technology, which can be body-worn, it is now possible to collect and store data on different aspects of human movement under the conditions of free living. This technology has the potential to be used in automated activity profiling systems which produce a continuous record of activity patterns over extended periods of time. Such activity profiling systems are dependent on classification algorithms which can effectively interpret body-worn sensor data and identify different activities. This article reviews the different techniques which have been used to classify normal activities and/or identify falls from body-worn sensor data. The review is structured according to the different analytical techniques and illustrates the variety of approaches which have previously been applied in this field. Although significant progress has been made in this important area, there is still significant scope for further work, particularly in the application of advanced classification techniques to problems involving many different activities. (topical review)

  8. Thin layer activation and ultra thin layer activation: two complementary techniques for wear and corrosion studies in various fields

    International Nuclear Information System (INIS)

    Sauvage, T.; Vincent, L.; Blondiaux, G.

    2002-01-01

    Thin layer activation (TLA) is widely used since more than 25 years to study surface wear or corrosion. This well known technique uses most of the time charged particles activation, which gives sensitivity in the range of the micrometer, except when the fluid mode of detection is utilized. In this case application of the method is limited to phenomena where we have transport of radioactive fragments to detection point. The main disadvantage of this procedure is the error due to trapping phenomena between the wear or corrosion point and detection setup. So the ultra thin layer activation (UTLA) has been developed to get nanometric sensitivity without using any fluid for radioactivity transportation, which is the main source of error of the TLA technique. In this paper we shall briefly describe the TLA technique and the most important fields of application. Then we shall emphasise on UTLA with a presentation of the principle of the method and actual running of application. The main problem concerning UTLA is calibration which requires the use of thin films (usually 10 to 100 nanometers) deposited on substrate. This process is time consuming and we shall demonstrate how running software developed in the lab can solve it. We shall finish the presentation by giving some potential application of the technique in various fields. (authors)

  9. Digital Control Techniques Based on Voltage Source Inverters in Renewable Energy Applications: A Review

    Directory of Open Access Journals (Sweden)

    Sohaib Tahir

    2018-02-01

    Full Text Available In the modern era, distributed generation is considered as an alternative source for power generation. Especially, need of the time is to provide the three-phase loads with smooth sinusoidal voltages having fixed frequency and amplitude. A common solution is the integration of power electronics converters in the systems for connecting distributed generation systems to the stand-alone loads. Thus, the presence of suitable control techniques, in the power electronic converters, for robust stability, abrupt response, optimal tracking ability and error eradication are inevitable. A comprehensive review based on design, analysis, validation of the most suitable digital control techniques and the options available for the researchers for improving the power quality is presented in this paper with their pros and cons. Comparisons based on the cost, schemes, performance, modulation techniques and coordinates system are also presented. Finally, the paper describes the performance evaluation of the control schemes on a voltage source inverter (VSI and proposes the different aspects to be considered for selecting a power electronics inverter topology, reference frames, filters, as well as control strategy.

  10. Behavior Change Techniques Present in Wearable Activity Trackers: A Critical Analysis.

    Science.gov (United States)

    Mercer, Kathryn; Li, Melissa; Giangregorio, Lora; Burns, Catherine; Grindrod, Kelly

    2016-04-27

    Wearable activity trackers are promising as interventions that offer guidance and support for increasing physical activity and health-focused tracking. Most adults do not meet their recommended daily activity guidelines, and wearable fitness trackers are increasingly cited as having great potential to improve the physical activity levels of adults. The objective of this study was to use the Coventry, Aberdeen, and London-Refined (CALO-RE) taxonomy to examine if the design of wearable activity trackers incorporates behavior change techniques (BCTs). A secondary objective was to critically analyze whether the BCTs present relate to known drivers of behavior change, such as self-efficacy, with the intention of extending applicability to older adults in addition to the overall population. Wearing each device for a period of 1 week, two independent raters used CALO-RE taxonomy to code the BCTs of the seven wearable activity trackers available in Canada as of March 2014. These included Fitbit Flex, Misfit Shine, Withings Pulse, Jawbone UP24, Spark Activity Tracker by SparkPeople, Nike+ FuelBand SE, and Polar Loop. We calculated interrater reliability using Cohen's kappa. The average number of BCTs identified was 16.3/40. Withings Pulse had the highest number of BCTs and Misfit Shine had the lowest. Most techniques centered around self-monitoring and self-regulation, all of which have been associated with improved physical activity in older adults. Techniques related to planning and providing instructions were scarce. Overall, wearable activity trackers contain several BCTs that have been shown to increase physical activity in older adults. Although more research and development must be done to fully understand the potential of wearables as health interventions, the current wearable trackers offer significant potential with regard to BCTs relevant to uptake by all populations, including older adults.

  11. Seismic active control by a heuristic-based algorithm

    International Nuclear Information System (INIS)

    Tang, Yu.

    1996-01-01

    A heuristic-based algorithm for seismic active control is generalized to permit consideration of the effects of control-structure interaction and actuator dynamics. Control force is computed at onetime step ahead before being applied to the structure. Therefore, the proposed control algorithm is free from the problem of time delay. A numerical example is presented to show the effectiveness of the proposed control algorithm. Also, two indices are introduced in the paper to assess the effectiveness and efficiency of control laws

  12. Performance improvement of a slip energy recovery drive system by a voltage-controlled technique

    Energy Technology Data Exchange (ETDEWEB)

    Tunyasrirut, Satean [Department of Instrumentation Engineering, Faculty of Engineering, Pathumwan Institute of Technology, 833 Rama1 Road, Pathumwan, Bangkok 10330 (Thailand); Kinnares, Vijit [Department of Electrical Engineering, Faculty of Engineering, King Mongkut' s Institute of Technology Ladkrabang, Bangkok 10520 (Thailand); Ngamwiwit, Jongkol [Department of Control Engineering, Faculty of Engineering, King Mongkut' s Institute of Technology Ladkrabang, Bangkok 10520 (Thailand)

    2010-10-15

    This paper introduces the performance improvement of a slip energy recovery drive system for the speed control of a wound rotor induction motor by a voltage-controlled technique. The slip energy occurred in the rotor circuit is transferred back to ac mains supply through a reactor instead of a step up transformer. The objective of the voltage-controlled technique is to increase power factor of the system and to reduce low order harmonics of the input line current. The drive system is designed and implemented using a voltage source inverter in conjunction with a boost chopper for DC link voltage, instead of a conventional drive using a 6 pulse converter or a Scherbius system. The slip power is recovered by the help of a voltage source inverter (VSI) based on a space vector pulse width modulation (SVPWM) technique. In order to keep the speed of the wound rotor induction motor constant over a certain range of operating conditions, the servo state feedback controller designed by a linear quadratic regulator (LQR) is also introduced in this paper. The overall control system is implemented on DSP, DS1104'TMS320F240 controller board. The performance improvement of the proposed system is tested in comparison with the conventional Scherbius system and the modified conventional Scherbius system by a 12 pulse converter in conjunction with a chopper at steady state and at dynamic conditions. A 220 W wound motor is employed for testing. It is found that the motor speed can be controlled to be constant in the operating range of 450-1200 rpm at no load and full load. It is also found that the efficiency of the proposed system is remarkably increased since the harmonics of the input ac line current is reduced while the ac line input power factor is increased. (author)

  13. 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…

  14. Applications of neutron activation analysis technique in the IPR-R1 research reactor

    International Nuclear Information System (INIS)

    Sabino, C.V.S.; Mansur, N.

    1986-01-01

    A review is made of the neutron activation analysis technique used in the IPR-R1 reactor of the Centro de Desenvolvimento da Tecnologia Nuclear - NUCLEBRAS. Some characteristics of the method are described, types of samples and elements analyzed are also mentioned. (Author) [pt

  15. Estimation of Anti-HIV Activity of HEPT Analogues Using MLR, ANN, and SVM Techniques

    Directory of Open Access Journals (Sweden)

    Basheerulla Shaik

    2013-01-01

    value than those of MLR and SVM techniques. Rm2= metrics and ridge regression analysis indicated that the proposed four-variable model MATS5e, RDF080u, T(O⋯O, and MATS5m as correlating descriptors is the best for estimating the anti-HIV activity (log 1/C present set of compounds.

  16. A comparison of maximal bioenergetic enzyme activities obtained with commonly used homogenization techniques.

    Science.gov (United States)

    Grace, M; Fletcher, L; Powers, S K; Hughes, M; Coombes, J

    1996-12-01

    Homogenization of tissue for analysis of bioenergetic enzyme activities is a common practice in studies examining metabolic properties of skeletal muscle adaptation to disease, aging, inactivity or exercise. While numerous homogenization techniques are in use today, limited information exists concerning the efficacy of specific homogenization protocols. Therefore, the purpose of this study was to compare the efficacy of four commonly used approaches to homogenizing skeletal muscle for analysis of bioenergetic enzyme activity. The maximal enzyme activity (Vmax) of citrate synthase (CS) and lactate dehydrogenase (LDH) were measured from homogenous muscle samples (N = 48 per homogenization technique) and used as indicators to determine which protocol had the highest efficacy. The homogenization techniques were: (1) glass-on-glass pestle; (2) a combination of a mechanical blender and a teflon pestle (Potter-Elvehjem); (3) a combination of the mechanical blender and a biological detergent; and (4) the combined use of a mechanical blender and a sonicator. The glass-on-glass pestle homogenization protocol produced significantly higher (P pestle homogenization protocol is the technique of choice for studying bioenergetic enzyme activity in skeletal muscle.

  17. An Active Damping Technique for Small DC-Link Capacitor Based Drive System

    DEFF Research Database (Denmark)

    Maheshwari, Ram Krishan; Munk-Nielsen, Stig; Lu, Kaiyuan

    2013-01-01

    A small dc-link capacitor based drive system shows instability when it is operated with large input line inductance at operating points with high power. This paper presents a simple, new active damping technique that can stabilize effectively the drive system at unstable operating points, offering...

  18. Control of Sound Transmission with Active-Passive Tiles

    OpenAIRE

    Goldstein, Andre L.

    2006-01-01

    Nowadays, numerous applications of active sound transmission control require lightweight partitions with high transmission loss over a broad frequency range and simple control strategies. In this work an active-passive sound transmission control approach is investigated that potentially addresses these requirements. The approach involves the use of lightweight stiff panels, or tiles, attached to a radiating base structure through active-passive soft mounts and covering the structure surface. ...

  19. The Trojan female technique: a novel, effective and humane approach for pest population control.

    Science.gov (United States)

    Gemmell, Neil J; Jalilzadeh, Aidin; Didham, Raphael K; Soboleva, Tanya; Tompkins, Daniel M

    2013-12-22

    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.

  20. The Trojan Female Technique: A Novel, Effective and Humane Approach for Pest Population Control

    Energy Technology Data Exchange (ETDEWEB)

    Gemmell, Neil J. [Centre for Reproduction and Genomics and Allan Wilson Centre for Molecular Ecology and Evolution, Department of Anatomy, University of Otago, Dunedin (New Zealand); Jalilzadeh, Aidin [Department of Mathematics and Statistics, University of Otago, Dunedin (New Zealand); Didham, Raphael K. [School of Animal Biology, University of Western Australia (Australia); CSIRO Ecosystem Sciences, Perth, Western Australia (Australia); Soboleva, Tanya [Science and Risk Assessment Directorate, Ministry for Primary Industries, PO Box 2526, Wellington (New Zealand); Tompkins, Daniel M. [Landcare Research, Private Bag 1930, Dunedin (New Zealand); New Zealand Institute for Plant and Food Research Ltd., Christchurch (New Zealand)

    2014-01-15

    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)

  1. Lower limb muscle activity during forefoot and rearfoot strike running techniques.

    Science.gov (United States)

    Landreneau, Lindsey L; Watts, Kayla; Heitzman, Jill E; Childers, W Lee

    2014-12-01

    Distance running offers a method to improve fitness but also has a risk of lower limb overuse injuries. Foot strike technique has been suggested as a method to alter loading of the lower limb and possibly minimize injury risk. However, there is a dearth of information regarding neuromuscular response to variations in running techniques. The purpose of this investigation was to compare the EMG activity that occurs during FFS running and RFS running, focusing on the biceps femoris, semitendenosis, rectus femoris, vastus medialis oblique, tibialis anterior (TA), medial head of gastrocnemeus (MGas), lateral head of gastrocnemius (LGas), and soleus. healthy adults (6 male, 8 female; age, 24.2 ± 0.8 years, height 170.1 ± 7.8 cm; mass 69.8 ±10.9 kg; Body Mass Index 24.1 ± 3.0 kg·m2) participated in the study. All participants performed a RFS and FFS running trial at 8.85 kph. A 3D motion capture system was used to collect kinematic data and electromyography was used to define muscle activity. Two-tailed paired t-tests were used to examine differences in outcomes between RFS and FFS conditions. The ankle was significantly more plantarflexed during FFS running (p = .0001) but there were no significant differences in knee and hip angles (p = .618 & .200, respectively). There was significantly less activity in tibialis anterior (TA) (p < .0001) and greater activity in the MGas (p= .020) during FFS running. The LGas and soleus did not change activity (p = .437 & .490, respectively). FFS running demonstrated lower muscular activity in the TA and increased activation in the MGas. FFS and RFS running have the potential to off-load injury prone tissues by changing between techniques. However, future studies will be necessary to establish more direct mechanistic connections between running technique and injury.

  2. 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...

  3. Radiation and isotopic techniques in the study and control of piroplasms of cattle: a review

    International Nuclear Information System (INIS)

    Irvin, A.D.; Brocklesby, D.W.; Purnell, R.E.

    1979-01-01

    Radiation and isotopic techniques have been used in a number of ways to study Babesia and Theileria parasites (piroplasms), and in attempts to vaccinate animals against diseases induced by these agents. Work involving the piroplasm infections of cattle is reviewed in this paper. Some success has been achieved by using radiation to modify tick or bovine stages of parasites, for use as potential vaccines. Radiation has also been used to induce immuno-suppression in laboratory animals, in an effort to render them susceptible to bovine piroplasms, particularly Theileria. Isotope tracer techniques have been used for labelling parasites, and for studying metabolic pathways. Encouraging results, particularly with regard to vaccine development, indicate the importance of radiation techniques in the study and control of piroplasms of cattle. (Auth.)

  4. A detailed study of inexpensive radon control techniques in New York state houses

    International Nuclear Information System (INIS)

    Nitschke, I.A.; Wadach, J.B.; Clarke, W.A.; Traynor, G.W.; Adams, G.P.; Rizzuto, J.E.

    1984-01-01

    As part of a comprehensive indoor air quality and infiltration field study, radon concentrations were measured in 60 houses in upstate New York using passive integrating monitors. Indoor air radon concentrations ranged from 0.2 pCi/l to 50 pCi/l. Four houses with the highest radon levels were then extensively monitored using real-time continuous instruments for the measurement of radon, radon daughters, respirable particles, infiltration, inside-outside pressure difference, and weather parameters. Several inexpensive radon mitigation techniques were tested in these four houses. Their effectiveness ranged widely. Techniques identified as effective were permanently installed in 14 houses having indoor air radon concentration above 2 pCi/l. Finally, the long-term effectiveness of the installed control techniques is being tested using passive integrating radon monitors. (Author)

  5. Proposal of a congestion control technique in LAN networks using an econometric model ARIMA

    Directory of Open Access Journals (Sweden)

    Joaquín F Sánchez

    2017-01-01

    Full Text Available Hasty software development can produce immediate implementations with source code unnecessarily complex and hardly readable. These small kinds of software decay generate a technical debt that could be big enough to seriously affect future maintenance activities. This work presents an analysis technique for identifying architectural technical debt related to non-uniformity of naming patterns; the technique is based on term frequency over package hierarchies. The proposal has been evaluated on projects of two popular organizations, Apache and Eclipse. The results have shown that most of the projects have frequent occurrences of the proposed naming patterns, and using a graph model and aggregated data could enable the elaboration of simple queries for debt identification. The technique has features that favor its applicability on emergent architectures and agile software development.

  6. 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

  7. Laboratory training manual on the use of nuclear techniques in insect research and control. 3. ed.

    International Nuclear Information System (INIS)

    1992-01-01

    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

  8. Development of welding technique by remote control at the JMTR Hot Laboratory

    International Nuclear Information System (INIS)

    Shimizu, Michio; Iwamatu, Sigemi; Takada, Humiki

    2000-03-01

    Several kinds of welding techniques have been systematically developed using the remote controlled procedures in the JMTR Hot Laboratory. These are as follows, (1) re-instrumentation's of FP gas pressure gauge and thermocouple to an irradiated fuel rod for the centerline temperature measurement, (2) welding of the un-irradiated/irradiated specimen and machining process to produce tensile test specimens, (3) fabrication of Co-60 radiation source from materials for reactivity adjustment in JMTR core, (4) re-capsuling of irradiated materials in the different types of irradiation facilities. These research and development of circumferential and sealed welding for capsuling and welding of irradiated specimen for re-irradiation were implemented under the remote-controlled conditions in the Hot Cell. These techniques will be very indispensable for supporting the irradiation experiments to be conducted in the JMTR. (author)

  9. Physical and chemical properties of gels. Application to protein nucleation control in the gel acupuncture technique

    Science.gov (United States)

    Moreno, Abel; Juárez-Martínez, Gabriela; Hernández-Pérez, Tomás; Batina, Nikola; Mundo, Manuel; McPherson, Alexander

    1999-09-01

    In this work, we present a new approach using analytical and optical techniques in order to determine the physical and chemical properties of silica gel, as well as the measurement of the pore size in the network of the gel by scanning electron microscopy. The gel acupuncture technique developed by García-Ruiz et al. (Mater. Res. Bull 28 (1993) 541) García-Ruiz and Moreno (Acta Crystallogr. D 50 (1994) 484) was used throughout the history of crystal growth. Several experiments were done in order to evaluate the nucleation control of model proteins (thaumatin I from Thaumatococcus daniellii, lysozyme from hen egg white and catalase from bovine liver) by the porous network of the gel. Finally, it is shown how the number and the size of the crystals obtained inside X-ray capillaries is controlled by the size of the porous structure of the gel.

  10. 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.

  11. Technology transfer of nuclear techniques and nucleonic control systems in the mineral industry

    International Nuclear Information System (INIS)

    1990-11-01

    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

  12. 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.

  13. Evaluation of Economic Merger Control Techniques Applied to the European Electricity Sector

    International Nuclear Information System (INIS)

    Vandezande, Leen; Meeus, Leonardo; Delvaux, Bram; Van Calster, Geert; Belmans, Ronnie

    2006-01-01

    With European electricity markets not yet functioning on a competitive basis and consolidation increasing, the European Commission has said it intends to more intensively apply competition law in the electricity sector. Yet economic techniques and theories used in EC merger control fail to take sufficiently into account some specific features of electricity markets. The authors offer suggestions to enhance their reliability and applicability in the electricity sector. (author)

  14. Thematic Plan for Fruit Fly Control Using the Sterile Insect Technique

    International Nuclear Information System (INIS)

    1999-01-01

    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.

  15. Emissions and prevention/control techniques for automobile body shops in Ciudad Juarez, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Jeffery, J.D.; Sager, M.

    1999-08-01

    Emissions of Volatile Organic Compounds (VOC) from automobile body repair shops are believed to be significant and to contribute to ozone nonattainment in El Paso, Texas and to violations of ozone air quality standards in Ciudad Juarez, Mexico. The Direccion de Desarrollo Urbano Y Ecologia (DDUE), (the local agency in Ciudad Juarez, Mexico) requested CICA's assistance in determining emissions from and identifying appropriate pollution prevention and control techniques for automobile body repair shops in Ciudad Juarez.

  16. Composite bonded magnets with controlled anisotropy directions prepared by viscous deformation technique

    International Nuclear Information System (INIS)

    Yamashita, Fumitoshi; Kawamura, Kiyomi; Okada, Yukihiro; Murakami, Hiroshi; Ogushi, Masaki; Nakano, Masaki; Fukunaga, Hirotoshi

    2007-01-01

    When a radially anisotropic rare earth bonded magnet for a rotor with a high (BH) max value is magnetized multi-polarly, its flux distributes rectangularly and increases a cogging torque. In order to overcome this difficulty, we newly developed highly dense Sm 2 Fe 17 N 3 and Nd 2 Fe 14 B-based composite bonded magnets with continuously controlled anisotropy directions by using a viscous deformation technique

  17. Environmental effects of energy production and utilization in the U.S. Volume 3. Techniques for controlling emissions

    International Nuclear Information System (INIS)

    Newkirk, H.W.

    1976-01-01

    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

  18. 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 ...

  19. 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.

  20. 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)

  1. 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.

  2. An integrated approach to the biomechanics and motor control of cricket fast bowling techniques.

    Science.gov (United States)

    Glazier, Paul S; Wheat, Jonathan S

    2014-01-01

    To date, scientific investigations into the biomechanical aspects of cricket fast bowling techniques have predominantly focused on identifying the mechanical factors that may predispose fast bowlers to lower back injury with a relative paucity of research being conducted on the technical features that underpin proficient fast bowling performance. In this review paper, we critique the scientific literature examining fast bowling performance. We argue that, although many published investigations have provided some useful insights into the biomechanical factors that contribute to a high ball release speed and, to a lesser extent, bowling accuracy, this research has not made a substantive contribution to knowledge enhancement and has only had a very minor influence on coaching practice. To significantly enhance understanding of cricket fast bowling techniques and, therefore, have greater impact on practice, we recommend that future scientific research adopts an interdisciplinary focus, integrating biomechanical measurements with the analytical tools and concepts of dynamical systems motor control theory. The use of qualitative (topological) analysis techniques, in particular, promises to increase understanding of the coordinative movement patterns that define 'technique' in cricket fast bowling and potentially help distinguish between functional and dysfunctional aspects of technique for individual fast bowlers.

  3. 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.

  4. HPLC-MS technique in radiopharmaceutical research (the quality control of 18F-2-fluorodeoxyglucose as an example)

    International Nuclear Information System (INIS)

    Macasek, F.

    2001-01-01

    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-[ 18 F]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/[ 19 F]FDG, xylitol, and also univalent ions of C 6 H 10 O 7 F.H 2 O and C 6 H 12 O 8 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)

  5. Dry diamond wire sawing techniques to be used in an active environment

    International Nuclear Information System (INIS)

    Loftus, S.

    2003-01-01

    Dry diamond wire sawing techniques usable in an active environment has the following benefits: - Reduced personnel exposure time due the remote control and operation of the cutting equipment, the operator is positioned outside the active cell when controlling the equipment; - The equipment will be reusable with only the diamond cutting wire and the drive wheel rubber inserts coming into contact with potentially contaminated material; - The reduced impact on the existing ventilation systems from fumes or particulate blinding in-cell filters. - No dismantling work has to be carried out on the object to make it suitable for cutting using diamond wire cutting; - The diamond wire is the only piece of equipment subject to short-term replacement due to wear. The paper presents the following issues: The project the equipment is to be used on; -The equipment to be used; - Cutting machine support frame; - Drive units; - Wire coolant device. The seconds part of the paper deals with in-active cutting trials. To produce a strategy for cutting up a vessel in an active facility, the cutting technique proposed for size reducing the vessel to be tested implies establishing its suitability before developing the cutting rig that will be used for the actual task. A mock-up of the vessel was manufactured and size reduced using an existing cutting rig located at the supplies works. This sets out and records the results of the trials performed to functionally demonstrate the adequacy of using a diamond wire to cut the vessel into several pieces. The trials were performed at Diamant Boart test facility in Brussels.The objectives of the vessel cutting trials were: - To assess if a double skinned mock-up of the vessel can be cut successfully, dry, using Diamant Boart diamond wire cooled using liquid nitrogen; - To optimise the cutting process to achieve maximum cutting speed, minimum nitrogen usage and optimise wire life; - To identify any changes to the cutting rig, heat exchanger or

  6. Applying the sterile insect technique to the control of insect pests

    International Nuclear Information System (INIS)

    LaChance, L.E.; Klassen, W.

    1991-01-01

    The sterile insect technique involves the mass-rearing of insects, which are sterilized by gamma rays from a 60 Co 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 F 1 sterility method in the eradication of local gypsy moth infestations. 18 refs, 5 figs, 1 tab

  7. A smart rotary technique versus conventional pulpectomy for primary teeth: A randomized controlled clinical study.

    Science.gov (United States)

    Mokhtari, Negar; Shirazi, Alireza-Sarraf; Ebrahimi, Masoumeh

    2017-11-01

    Techniques with adequate accuracy of working length determination along with shorter duration of treatment in pulpectomy procedure seems to be essential in pediatric dentistry. The aim of the present study was to evaluate the accuracy of root canal length measurement with Root ZX II apex locator and rotary system in pulpectomy of primary teeth. In this randomized control clinical trial complete pulpectomy was performed on 80 mandibular primary molars in 80, 4-6-year-old children. The study population was randomly divided into case and control groups. In control group conventional pulpectomy was performed and in the case group working length was determined by electronic apex locator Root ZXII and instrumented with Mtwo rotary files. Statistical evaluation was performed using Mann-Whitney and Chi-Square tests ( P <0.05). There were no significant differences between electronic apex locator Root ZXII and conventional method in accuracy of root canal length determination. However significantly less time was needed for instrumenting with rotary files ( P =0.000). Considering the comparable results in accuracy of root canal length determination and the considerably shorter instrumentation time in Root ZXII apex locator and rotary system, it may be suggested for pulpectomy in primary molar teeth. Key words: Rotary technique, conventional technique, pulpectomy, primary teeth.

  8. Active damping based on decoupled collocated control

    NARCIS (Netherlands)

    Holterman, J.; de Vries, Theodorus J.A.; Auer, Frank; Gardonio, P.; Rafaely, B.

    2002-01-01

    High-precision machines typically suffer from small but persistent vibrations. As it is difficult to damp these vibrations by passive means, research at the Drebbel Institute at the University of Twente is aimed at the development of an active structural element that can be used for vibration

  9. Applying the sterile insect technique to the control of insect pests

    International Nuclear Information System (INIS)

    LaChance, L.E.; Klassen, W.

    1991-01-01

    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 60 Co 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

  10. Applying the sterile insect technique to the control of insect pests

    Energy Technology Data Exchange (ETDEWEB)

    LaChance, L E; Klassen, W [Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, Vienna (Austria)

    1991-09-01

    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 {sup 60}Co 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.

  11. Activated sludge characterization through microscopy: A review on quantitative image analysis and chemometric techniques

    Energy Technology Data Exchange (ETDEWEB)

    Mesquita, Daniela P. [IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Amaral, A. Luís [IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal); Instituto Politécnico de Coimbra, ISEC, DEQB, Rua Pedro Nunes, Quinta da Nora, 3030-199 Coimbra (Portugal); Ferreira, Eugénio C., E-mail: ecferreira@deb.uminho.pt [IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, Universidade do Minho, Campus de Gualtar, 4710-057 Braga (Portugal)

    2013-11-13

    Graphical abstract: -- Highlights: •Quantitative image analysis shows potential to monitor activated sludge systems. •Staining techniques increase the potential for detection of operational problems. •Chemometrics combined with quantitative image analysis is valuable for process monitoring. -- Abstract: In wastewater treatment processes, and particularly in activated sludge systems, efficiency is quite dependent on the operating conditions, and a number of problems may arise due to sludge structure and proliferation of specific microorganisms. In fact, bacterial communities and protozoa identification by microscopy inspection is already routinely employed in a considerable number of cases. Furthermore, quantitative image analysis techniques have been increasingly used throughout the years for the assessment of aggregates and filamentous bacteria properties. These procedures are able to provide an ever growing amount of data for wastewater treatment processes in which chemometric techniques can be a valuable tool. However, the determination of microbial communities’ properties remains a current challenge in spite of the great diversity of microscopy techniques applied. In this review, activated sludge characterization is discussed highlighting the aggregates structure and filamentous bacteria determination by image analysis on bright-field, phase-contrast, and fluorescence microscopy. An in-depth analysis is performed to summarize the many new findings that have been obtained, and future developments for these biological processes are further discussed.

  12. 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.

  13. Modelling Aedes aegypti mosquito control via transgenic and sterile insect techniques: Endemics and emerging outbreaks

    KAUST Repository

    Seirin Lee, S.; Baker, R.E.; Gaffney, E.A.; White, S.M.

    2013-01-01

    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.

  14. Comparative study between the PIXE technique and neutron activation analysis for Zinc determination

    International Nuclear Information System (INIS)

    Cruvinel, Paulo Estevao; Crestana, Silvio; Artaxo Netto, Paulo Eduardo

    1997-01-01

    This work presents a comparative study between the PIXE, proton beams and neutron activation analysis (NAA) techniques, for determination of total zinc concentration. Particularly, soil samples from the Pindorama, Instituto Agronomico de Campinas, Sao Paulo State, Brazil, experimental station have been analysed and measuring the zinc contents in μg/g. The results presented good correlation between the mentioned techniques. The PIXE and NAA analyses have been carried out by using the series S, 2.4 MeV proton beams Pelletron accelerator and the IPEN/CNEN-IEA-R1 reactor, both installed at the Sao Paulo - Brazil university

  15. Biomimetic propulsion under random heaving conditions, using active pitch control

    Science.gov (United States)

    Politis, Gerasimos; Politis, Konstantinos

    2014-05-01

    Marine mammals travel long distances by utilizing and transforming wave energy to thrust through proper control of their caudal fin. On the other hand, manmade ships traveling in a wavy sea store large amounts of wave energy in the form of kinetic energy for heaving, pitching, rolling and other ship motions. A natural way to extract this energy and transform it to useful propulsive thrust is by using a biomimetic wing. The aim of this paper is to show how an actively pitched biomimetic wing could achieve this goal when it performs a random heaving motion. More specifically, we consider a biomimetic wing traveling with a given translational velocity in an infinitely extended fluid and performing a random heaving motion with a given energy spectrum which corresponds to a given sea state. A formula is invented by which the instantaneous pitch angle of the wing is determined using the heaving data of the current and past time steps. Simulations are then performed for a biomimetic wing at different heave energy spectra, using an indirect Source-Doublet 3-D-BEM, together with a time stepping algorithm capable to track the random motion of the wing. A nonlinear pressure type Kutta condition is applied at the trailing edge of the wing. With a mollifier-based filtering technique, the 3-D unsteady rollup pattern created by the random motion of the wing is calculated without any simplifying assumptions regarding its geometry. Calculated unsteady forces, moments and useful power, show that the proposed active pitch control always results in thrust producing motions, with significant propulsive power production and considerable beneficial stabilizing action to ship motions. Calculation of the power required to set the pitch angle prove it to be a very small percentage of the useful power and thus making the practical application of the device very tractable.

  16. Modelling and Design of Active Thermal Controls for Power Electronics of Motor Drive Applications

    DEFF Research Database (Denmark)

    Vernica, Ionut; Blaabjerg, Frede; Ma, Ke

    2017-01-01

    of active thermal control methods for the power devices of a motor drive application. The motor drive system together with the thermal cycling of the power devices have been modelled, and adverse temperature swings could be noticed during the start-up and deceleration periods of the motor. Based...... on the electrical response of the system, the junction temperature of the semiconductor devices is estimated, and consequently three active thermal control methods are proposed and practically designed with respect to the following parameters: switching frequency, deceleration slope and modulation technique....... Finally, experimental results are provided in order to validate the effectiveness of the proposed control methods....

  17. Switching EKF technique for rotor and stator resistance estimation in speed sensorless control of IMs

    International Nuclear Information System (INIS)

    Barut, Murat; Bogosyan, Seta; Gokasan, Metin

    2007-01-01

    High performance speed sensorless control of induction motors (IMs) calls for estimation and control schemes that offer solutions to parameter uncertainties as well as to difficulties involved with accurate flux/velocity estimation at very low and zero speed. In this study, a new EKF based estimation algorithm is proposed for the solution of both problems and is applied in combination with speed sensorless direct vector control (DVC). The technique is based on the consecutive execution of two EKF algorithms, by switching from one algorithm to another at every n sampling periods. The number of sampling periods, n, is determined based on the desired system performance. The switching EKF approach, thus applied, provides an accurate estimation of an increased number of parameters than would be possible with a single EKF algorithm. The simultaneous and accurate estimation of rotor, R r ' and stator, R s resistances, both in the transient and steady state, is an important challenge in speed sensorless IM control and reported studies achieving satisfactory results are few, if any. With the proposed technique in this study, the sensorless estimation of R r ' and R s is achieved in transient and steady state and in both high and low speed operation while also estimating the unknown load torque, velocity, flux and current components. The performance demonstrated by the simulation results at zero speed, as well as at low and high speed operation is very promising when compared with individual EKF algorithms performing either R r ' or R s estimation or with the few other approaches taken in past studies, which require either signal injection and/or a change of algorithms based on the speed range. The results also motivate utilization of the technique for multiple parameter estimation in a variety of control methods

  18. Refolding techniques for recovering biologically active recombinant proteins from inclusion bodies.

    Science.gov (United States)

    Yamaguchi, Hiroshi; Miyazaki, Masaya

    2014-02-20

    Biologically active proteins are useful for studying the biological functions of genes and for the development of therapeutic drugs and biomaterials in a biotechnology industry. Overexpression of recombinant proteins in bacteria, such as Escherichia coli, often results in the formation of inclusion bodies, which are protein aggregates with non-native conformations. As inclusion bodies contain relatively pure and intact proteins, protein refolding is an important process to obtain active recombinant proteins from inclusion bodies. However, conventional refolding methods, such as dialysis and dilution, are time consuming and, often, recovered yields of active proteins are low, and a trial-and-error process is required to achieve success. Recently, several approaches have been reported to refold these aggregated proteins into an active form. The strategies largely aim at reducing protein aggregation during the refolding procedure. This review focuses on protein refolding techniques using chemical additives and laminar flow in microfluidic chips for the efficient recovery of active proteins from inclusion bodies.

  19. Study of wear in piston ring of the vehicle engine using thin layer activation technique

    International Nuclear Information System (INIS)

    Khan, I.H.; Farooq, M.; Ghiyas-ud-Din; Gul, S.; Qureshi, R.M.; Jin Joon Ha; Wallace, G.

    2004-01-01

    Thin Layer Activation (TLA) technique was used to investigate piston ring wear of a six cylinders vehicle engine at various engine speeds and load conditions. The activated ring was installed in cylinder no.5 of the engine at middle position (compression ring). Monitoring was carried out on-line (extremely on the engine block) using 'Thin Layer Difference Method'. The calibration curve of the activity profile was prepared with the help of activation parameters determined at the time of ring activation in particle accelerator. The results show that the piston ring wear varies from 0.309 micron/hour to 0.404 micron/hour at given engine speed and load conditions. (author)

  20. Measurements of fusion neutron yields by neutron activation technique: Uncertainty due to the uncertainty on activation cross-sections

    Energy Technology Data Exchange (ETDEWEB)

    Stankunas, Gediminas, E-mail: gediminas.stankunas@lei.lt [Lithuanian Energy Institute, Laboratory of Nuclear Installation Safety, Breslaujos str. 3, LT-44403 Kaunas (Lithuania); EUROfusion Consortium, JET, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Batistoni, Paola [ENEA, Via E. Fermi, 45, 00044 Frascati, Rome (Italy); EUROfusion Consortium, JET, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Sjöstrand, Henrik; Conroy, Sean [Department of Physics and Astronomy, Uppsala University, PO Box 516, SE-75120 Uppsala (Sweden); EUROfusion Consortium, JET, Culham Science Centre, Abingdon OX14 3DB (United Kingdom)

    2015-07-11

    The neutron activation technique is routinely used in fusion experiments to measure the neutron yields. This paper investigates the uncertainty on these measurements as due to the uncertainties on dosimetry and activation reactions. For this purpose, activation cross-sections were taken from the International Reactor Dosimetry and Fusion File (IRDFF-v1.05) in 640 groups ENDF-6 format for several reactions of interest for both 2.5 and 14 MeV neutrons. Activation coefficients (reaction rates) have been calculated using the neutron flux spectra at JET vacuum vessel, both for DD and DT plasmas, calculated by MCNP in the required 640-energy group format. The related uncertainties for the JET neutron spectra are evaluated as well using the covariance data available in the library. These uncertainties are in general small, but not negligible when high accuracy is required in the determination of the fusion neutron yields.